WorldWideScience

Sample records for current performance levels

  1. Blade design and performance analysis on the horizontal axis tidal current turbine for low water level channel

    International Nuclear Information System (INIS)

    Chen, C C; Choi, Y D; Yoon, H Y

    2013-01-01

    Most tidal current turbine design are focused on middle and large scale for deep sea, less attention was paid in low water level channel, such as the region around the islands, coastal seas and rivers. This study aims to develop a horizontal axis tidal current turbine rotor blade which is applicable to low water level island region in southwest of Korea. The blade design is made by using BEMT(blade element momentum theory). The section airfoil profile of NACA63-415 is used, which shows good performance of lift coefficient and drag coefficient. Power coefficient, pressure and velocity distributions are investigated according to TSR by CFD analysis

  2. The Effect of Cerebellar Transcranial Direct Current Stimulation on A Throwing Task Depends on Individual Level of Task Performance.

    Science.gov (United States)

    Mizuguchi, Nobuaki; Katayama, Takashi; Kanosue, Kazuyuki

    2018-02-10

    The effect of cerebellar transcranial direct current stimulation (tDCS) on motor performance remains controversial. Some studies suggest that the effect of tDCS depends upon task-difficulty and individual level of task performance. Here, we investigated whether the effect of cerebellar tDCS on the motor performance depends upon the individual's level of performance. Twenty-four naïve participants practiced dart throwing while receiving a 2-mA cerebellar tDCS for 20 min under three stimulus conditions (anodal-, cathodal-, and sham-tDCS) on separate days with a double-blind, counter-balanced cross-over design. Task performance was assessed by measuring the distance between the center of the bull's eye and the dart's position. Although task performance tended to improve throughout the practice under all stimulus conditions, improvement within a given day was not significant as compared to the first no-stimulus block. In addition, improvement did not differ among stimulation conditions. However, the magnitude of improvement was associated with an individual's level of task performance only under cathodal tDCS condition (p performance improvement only for the sub-group of participants with lower performance levels as compared to that with sham-tDCS (p task performance. Thus, cerebellar tDCS would facilitate learning of a complex motor skill task only in a subset of individuals. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Pulse width modulated buck-boost five-level current source inverters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Gao, F.; Loh, P.C.

    2008-01-01

    , resulting in the natural balance of input current. For maintaining the normalized volt-sec average unchanged, the alternative phase opposition disposition (APOD) modulation scheme with typical gating signal mapping technique from voltage source inverter (VSI) to CSI can be assumed to control the five......This paper presents new five-level current source inverters (CSIs) with voltage/current buck-boost capability. Being different from the existing multilevel CSI, the proposed CSIs were first designed to regulate the flowing path of dc input current by controlling two additional active switches......-level buck-boost CSIs. Next by observing the hidden current charging path during inductive charging interval under APOD modulation, it is noted that the buck-boost five-level CSI can then be further modified with lesser active component without degrading output performance. To verify the theoretical findings...

  4. Current level detector

    International Nuclear Information System (INIS)

    Kerns, C.R.

    1977-01-01

    A device is provided for detecting the current level of a dc signal. It includes an even harmonic modulator to which a reference ac signal is applied. The unknown dc signal acts on the reference ac signal so that the output of the modulator includes an even harmonic whose amplitude is proportional to the unknown dc current. The device may be used to provide overcurrent protection for proportional wire chambers

  5. Study on current limiting characteristics of SFCL with two trigger current levels

    International Nuclear Information System (INIS)

    Lim, S.H.

    2010-01-01

    In this paper, the superconducting fault current limiter (SFCL) with two trigger current levels was suggested and its effectiveness through the analysis on the current limiting characteristics was described. The proposed SFCL, which consists of the triggering and the limiting components, can limit the fault current by generating the limiting impedance through two steps according to the amplitude of the initial fault current. In case that the fault happens, the lower initial fault current causes the only superconducting element of the triggering component to be quenched. On the other hand, the higher initial fault current makes both the superconducting elements comprising the triggering and the limiting components of the SFCL to be quenched, which contributes to the higher impedance of the SFCL. Therefore, the effective fault current limiting operation of the SFCL can be performed by generating the SFCL's impedance in proportion to the amplitude of the initial fault current. To confirm the current limiting operation of the proposed SFCL, the short-circuit tests of the SFCL according to the fault angle were carried out and its effective fault current limiting operations could be discussed.

  6. Current DOE direction in low-level waste management

    International Nuclear Information System (INIS)

    Wilhite, E.L.; Dolenc, M.R.; Shupe, M.W.; Waldo, L.C.

    1989-01-01

    The U.S. Department of Energy (DOE) is implementing revised DOE Order 5820.2A Radioactive Waste Management. Chapter III of the revised order provides prescriptive requirements for managing low-level waste and is the subject of this paper. The revised order requires that all DOE low-level radioactive and mixed waste be systematically managed, using an approach that considers the combination of waste management practices used in waste generation reduction, segregation, treatment, packaging, storage, and disposal. The Order defines performance objectives for protecting groundwater, for protecting against intrusion, and for maintaining adequate operational practices. A performance assessment will be required to ensure that waste management operations comply with these performance objectives. DOE implementation of the revised Order includes work in the areas of leach testing, waste stabilization, waste certification, facility monitoring, and management of unique waste streams. This paper summarizes the status of this work and the current direction DOE is taking in managing low-level waste under DOE 5820.2A

  7. Treatment of uncertainty in low-level waste performance assessment

    International Nuclear Information System (INIS)

    Kozak, M.W.; Olague, N.E.; Gallegos, D.P.; Rao, R.R.

    1991-01-01

    Uncertainties arise from a number of different sources in low-level waste performance assessment. In this paper the types of uncertainty are reviewed, and existing methods for quantifying and reducing each type of uncertainty are discussed. These approaches are examined in the context of the current low-level radioactive waste regulatory performance objectives, which are deterministic. The types of uncertainty discussed in this paper are model uncertainty, uncertainty about future conditions, and parameter uncertainty. The advantages and disadvantages of available methods for addressing uncertainty in low-level waste performance assessment are presented. 25 refs

  8. 24 CFR 990.175 - Utilities expense level: Computation of the current consumption level.

    Science.gov (United States)

    2010-04-01

    ...: Computation of the current consumption level. 990.175 Section 990.175 Housing and Urban Development... Calculating Formula Expenses § 990.175 Utilities expense level: Computation of the current consumption level. The current consumption level shall be the actual amount of each utility consumed during the 12-month...

  9. Performance assessment strategy for low-level waste disposal sites

    International Nuclear Information System (INIS)

    Starmer, R.J.; Deering, L.G.; Weber, M.F.

    1988-01-01

    This paper describes US Nuclear Regulatory Commission (NRC) staff views on predicting the performance of low-level radioactive waste disposal facilities. Under the Atomic Energy Act, as amended, and the Low Level Radioactive Waste Policy Act, as amended, the NRC and Agreement States license land disposal of low-level radioactive waste (LLW) using the requirements in 10 CFR Part 61 or comparable state requirements. The purpose of this paper is to briefly describe regulatory requirements for performance assessment in low-level waste licensing, a strategy for performance assessments to support license applications, and NRC staff licensing evaluation of performance assessments. NRC's current activities in developing a performance assessment methodology will provide an overall systems modeling approach for assessing the performance of LLW disposal facilities. NRC staff will use the methodology to evaluate performance assessments conducted by applicants for LLW disposal facilities. The methodology will be made available to states and other interested parties

  10. The relationship between chiropractor required and current level of business knowledge.

    Science.gov (United States)

    Ciolfi, Michael Anthony; Kasen, Patsy Anne

    2017-01-01

    Chiropractors frequently practice within health care systems requiring the business acumen of an entrepreneur. However, some chiropractors do not know the relationship between the level of business knowledge required for practice success and their current level of business knowledge. The purpose of this quantitative study was to examine the relationship between chiropractors' perceived level of business knowledge required and their perceived level of current business knowledge. Two hundred and seventy-four participants completed an online survey (Health Care Training and Education Needs Survey) which included eight key business items. Participants rated the level of perceived business knowledge required (Part I) and their current perceived level of knowledge (Part II) for the same eight items. Data was collected from November 27, 2013 to December 18, 2013. Data were analyzed using Spearman's ranked correlation to determine the statistically significant relationships for the perceived level of knowledge required and the perceived current level of knowledge for each of the paired eight items from Parts I and II of the survey. Wilcoxon Signed Ranks Tests were performed to determine the statistical difference between the paired items. The results of Spearman's correlation testing indicated a statistically significant ( p business items (6 of 8) however a statistically difference was demonstrated in only three of the paired business items. The implications of this study for social change include the potential to improve chiropractors' business knowledge and skills, enable practice success, enhance health services delivery and positively influence the profession as a viable career.

  11. Current conserving theory at the operator level

    Science.gov (United States)

    Yuan, Jiangtao; Wang, Yin; Wang, Jian

    The basic assumption of quantum transport in mesoscopic systems is that the total charge inside the scattering region is zero. This means that the potential deep inside reservoirs is effectively screened and therefore the electric field at interface of scattering region is zero. Thus the current conservation condition can be satisfied automatically which is an important condition in mesoscopic transport. So far the current conserving ac theory is well developed by considering the displacement current which is due to Coulomb interaction if we just focus on the average current. However, the frequency dependent shot noise does not satisfy the conservation condition since we do not consider the current conservation at the operator level. In this work, we formulate a generalized current conserving theory at the operator level using non-equilibrium Green's function theory which could be applied to both average current and frequency dependent shot noise. A displacement operator is derived for the first time so that the frequency dependent correlation of displacement currents could be investigated. Moreover, the equilibrium shot noise is investigated and a generalized fluctuation-dissipation relationship is presented.

  12. Relative Price Levels and Current Accounts: An Exploration

    Directory of Open Access Journals (Sweden)

    Joshua Aizenman

    2008-12-01

    Full Text Available This paper studies the links between current accounts and relative price levels, finding that current account changes are associated with sizable future relative price levels effects. This is done in panel regressions of the Penn effect, adding a lagged current account/GDP and other explanatory variables. Higher GDP/ capita and a greater export share of manufacturing tend to mitigate the real exchange rate impact of lagged current accounts. Active management of current accounts may provide a powerful adjustment channel, mitigating the real exchange rate effects of volatile terms of trade, and may explain the growing proliferation of Sovereign Wealth Funds.

  13. Current and sea-level signals in periplatform ooze (Neogene, Maldives, Indian Ocean)

    Science.gov (United States)

    Betzler, Christian; Lüdmann, Thomas; Hübscher, Christian; Fürstenau, Jörn

    2013-05-01

    Periplatform ooze is an admixture of pelagic carbonate and sediment derived from neritic carbonate platforms. Compositional variations of periplatform ooze allow the reconstruction of past sea-level changes. Periplatform ooze formed during sea-level highstands is finer grained and richer in aragonite through the elevated input of material from the flooded platform compared to periplatform ooze formed during the episodes of lowered sea level. In many cases, however, the sea floor around carbonate platforms is subjected to bottom currents which are expected to affect sediment composition, i.e. through winnowing of the fine fraction. The interaction of sea-level driven highstand shedding and current impact on the formation of periplatform ooze has hitherto not been analyzed. To test if a sea-level driven input signal in periplatform ooze is influenced or even distorted by changing current activity, an integrated study using seismic, hydroacoustic and sedimentological data has been performed on periplatform ooze deposited in the Inner Sea of the Maldives. The Miocene to Pleistocene succession of drift deposits is subdivided into nine units; limits of seismostratigraphic units correspond to changes or turnarounds in grain size trends in cores recovered at ODP Site 716 and NEOMA Site 1143. For the Pleistocene it can be shown how changes in grain size occur in concert with sea-level changes and changes of the monsoonal system, which is thought to be a major driver of bottom currents in the Maldives. A clear highstand shedding pattern only appears in the data at a time of relaxation of monsoonal strength during the last 315 ky. Results imply (1) that drift sediments provide a potential target for analyzing past changes in oceanic currents and (2) that the ooze composition bears a mixed signal of input and physical winnowing at the sea floor.

  14. A new high performance current transducer

    International Nuclear Information System (INIS)

    Tang Lijun; Lu Songlin; Li Deming

    2003-01-01

    A DC-100 kHz current transducer is developed using a new technique on zero-flux detecting principle. It was shown that the new current transducer is of high performance, its magnetic core need not be selected very stringently, and it is easy to manufacture

  15. Historical Trust Levels Predict Current Welfare State Design

    DEFF Research Database (Denmark)

    Bergh, Andreas; Bjørnskov, Christian

    Using cross-sectional data for 76 countries, we apply instrumental variable techniques based on pronoun drop, temperature and monarchies to demonstrate that historical trust levels predict several indicators of current welfare state design, including universalism and high levels of regulatory...... freedom. We argue that high levels of trust and trustworthiness are necessary, but not sufficient, conditions for societies to develop successful universal welfare states that would otherwise be highly vulnerable to free riding and fraudulent behavior. Our results do not exclude positive feedback from...... welfare state universalism to individual trust, although we claim that the important causal link runs from historically trust levels to current welfare state design....

  16. Stable superconducting magnet. [high current levels below critical temperature

    Science.gov (United States)

    Boom, R. W. (Inventor)

    1967-01-01

    Operation of a superconducting magnet is considered. A method is described for; (1) obtaining a relatively high current in a superconducting magnet positioned in a bath of a gas refrigerant; (2) operating a superconducting magnet at a relatively high current level without training; and (3) operating a superconducting magnet containing a plurality of turns of a niobium zirconium wire at a relatively high current level without training.

  17. Intelligence Level Performance Standards Research for Autonomous Vehicles.

    Science.gov (United States)

    Bostelman, Roger B; Hong, Tsai H; Messina, Elena

    2015-01-01

    United States and European safety standards have evolved to protect workers near Automatic Guided Vehicles (AGV's). However, performance standards for AGV's and mobile robots have only recently begun development. Lessons can be learned from research and standards efforts for mobile robots applied to emergency response and military applications. Research challenges, tests and evaluations, and programs to develop higher intelligence levels for vehicles can also used to guide industrial AGV developments towards more adaptable and intelligent systems. These other efforts also provide useful standards development criteria for AGV performance test methods. Current standards areas being considered for AGVs are for docking, navigation, obstacle avoidance, and the ground truth systems that measure performance. This paper provides a look to the future with standards developments in both the performance of vehicles and the dynamic perception systems that measure intelligent vehicle performance.

  18. Five-Level Current-Source Inverters With Buck–Boost and Inductive-Current Balancing Capabilities

    DEFF Research Database (Denmark)

    Gao, Feng; Loh, Poh Chiang; Blaabjerg, Frede

    2010-01-01

    This paper presents new five-level current-source inverters (CSIs) with voltage/current buck–boost capability, unlike existing five-level CSIs where only voltage–boost operation is supported. The proposed inverters attain self-inductive-currentbalancing per switching cycle at their dc front ends...... without having to include additional balancing hardware or complex control manipulation. The inverters can conveniently be controlled by using the well-established phase-shifted carrier modulation scheme with only two additional linear references and a mapping logic table needed. Existing modulators can...

  19. Analysis on current limiting characteristics of a transformer type SFCL with two triggering current levels

    International Nuclear Information System (INIS)

    Lim, Sung-Hun; Ko, Seckcheol; Han, Tae-Hee

    2013-01-01

    Highlights: ► We suggested the transformer type SFCL with two triggering current levels. ► The short-circuit tests for the suggested SFCL was executed. ► The fault angle as the fault conditions to verify its operation was selected. ► The usefulness of the suggested SFCL was confirmed through the short-circuit test. -- Abstract: In this paper, the transformer type superconducting fault current limiter (SFCL) with two triggering current levels was suggested and its current limiting characteristics were analyzed. The structure of the suggested transformer type SFCL with two triggering current levels largely consists of two parts. One is the transformer with two magnetically coupled coils, which correspond to the primary winding and the secondary one connected with one high-T C superconducting (HTSC) element. The other is third coil, or, another secondary winding with one HTSC element, which is wound on the same iron core together with two coils. This suggested transformer type SFCL can limit the fault current by generating its limiting impedance with two different amplitudes, which are dependent on the initial amplitude of the fault current in case of the fault occurrence. To confirm the usefulness of the proposed SFCL, the current limiting tests of the SFCL according to the fault angle, one of the effective fault conditions to affect the amplitude of the initial fault current, were carried out and its effective limiting operations were discussed

  20. Correlation between physics A-levels/A-levels and degree performance

    Science.gov (United States)

    Chadwick, Roy

    1985-09-01

    The author presents an analysis of 178 students who left Solihull Sixth form College between 1975 and 1981 to do a degree in physics (approximately one third) or engineering (approximately two thirds) at university or polytechnic. The first table is an analysis of physics A-level grade and degree performance; the second table an analysis of the points total for physics A-level plus maths A-level (five for A, four for B, etc.), against degree performances, and the final table an analysis of the points total for physics A-level plus maths A-level plus third A-level (again five for A, four for B, etc.), against degree performance.

  1. Transmission Level High Temperature Superconducting Fault Current Limiter

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Gary [SuperPower, Inc., Schenectady, NY (United States)

    2016-10-05

    The primary objective of this project was to demonstrate the feasibility and reliability of utilizing high-temperature superconducting (HTS) materials in a Transmission Level Superconducting Fault Current Limiter (SFCL) application. During the project, the type of high-temperature superconducting material used evolved from 1st generation (1G) BSCCO-2212 melt cast bulk high-temperature superconductors to 2nd generation (2G) YBCO-based high-temperature superconducting tape. The SFCL employed SuperPower's “Matrix” technology, that offers modular features to enable scale up to transmission voltage levels. The SFCL consists of individual modules that contain elements and parallel inductors that assist in carrying the current during the fault. A number of these modules are arranged in an m x n array to form the current-limiting matrix.

  2. Current Developments in Community College Performance Funding

    Science.gov (United States)

    D'Amico, Mark M.; Friedel, Janice N.; Katsinas, Stephen G.; Thornton, Zoë M.

    2014-01-01

    Since the initiation of performance funding in Tennessee in the late 1970s, approximately 30 states have, at some point, attempted a funding model that includes performance on a set of indicators. The purpose of the present study was to capture the current status of performance funding in public statewide community college systems and to assess…

  3. History of Aral Sea level variability and current scientific debates

    Science.gov (United States)

    Cretaux, Jean-François; Letolle, René; Bergé-Nguyen, Muriel

    2013-11-01

    The Aral Sea has shrunk drastically over the past 50 years, largely due to water abstraction from the Amu Darya and Syr Darya rivers for land irrigation. Over a longer timescale, Holocene palaeolimnological reconstruction of variability in water levels of the Aral Sea since 11,700 BP indicates a long history of alternating phases of regression and transgression, which have been attributed variously to climate, tectonic and anthropogenic forcing. The hydrological history of the Aral Sea has been investigated by application of a variety of scientific approaches, including archaeology, palaeolimnological palaeoclimate reconstruction, geophysics, sedimentology, and more recently, space science. Many issues concerning lake level variability over the Holocene and more recent timescales, and the processes that drive the changes, are still a matter for active debate. Our aim in this article is to review the current debates regarding key issues surrounding the causes and magnitude of Aral Sea level variability on a variety of timescales from months to thousands of years. Many researchers have shown that the main driving force of Aral Sea regressions and transgressions is climate change, while other authors have argued that anthropogenic forcing is the main cause of Aral Sea water level variations over the Holocene. Particular emphasis is made on contributions from satellite remote sensing data in order to improve our understanding of the influence of groundwater on the current hydrological water budget of the Aral Sea since 2005. Over this period of time, water balance computation has been performed and has shown that the underground water inflow to the Aral Sea is close to zero with an uncertainty of 3 km3/year.

  4. Designing PV Incentive Programs to Promote Performance: A Reviewof Current Practice

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen; Wiser, Ryan; Bolinger, Mark

    2007-06-01

    Increasing levels of financial support for customer-sited photovoltaic (PV) systems, provided through publicly-funded incentive programs, has heightened concerns about the long-term performance of these systems. Given the barriers that customers face to ensuring that their PV systems perform well, and the responsibility that PV incentive programs bear to ensure that public funds are prudently spent, these programs should, and often do, play a critical role in ensuring that PV systems receiving incentives perform well. To provide a point of reference for assessing the current state of the art, and to inform program design efforts going forward, we examine the approaches to encouraging PV system performance used by 32 prominent PV incentive programs in the U.S. We identify eight general strategies or groups of related strategies that these programs have used to address performance issues, and highlight important differences in the implementation of these strategies among programs.

  5. Performance of the Public Expenditure Management at Local Level in Romania

    Directory of Open Access Journals (Sweden)

    Ani MATEI

    2008-06-01

    Full Text Available The current paper aims to analyze the performance of the public expenditure management based on the decrease of the administrative costs. The paper is grounded on the following premises: (1 Romania as an EU Member State is under a continuous process to harmonize its legislation with the EU legislation. (2 The integration of Romania in EU in 2007 has determined a significant change in the administrative expenditure amount. (3 Strengthening local autonomy through the decentralization and the devolution processes emphasizes clearer the need for improving the performance of the expenditure management at local level. (4 Internal order, flows of communication and transfer, synergy of the governance system assume administrative expenditure that can be determined. (5 The performance of public organizations in managing local governance issues depends directly also on the administrative expenditure level**. [** Paper accepted to be presented at the Fourth TransAtlantic Dialogue “The Status of Inter-Governmental Relations and Multi-Level Governance in Europe and the US”, Workshop 5: “Performance measurement and accountability in IGR-MLG”.

  6. Investigating Student Choices in Performing Higher-Level Comprehension Tasks Using TED

    Science.gov (United States)

    Bianchi, Francesca; Marenzi, Ivana

    2016-01-01

    The current paper describes a first experiment in the use of TED talks and open tagging exercises to train higher-level comprehension skills, and of automatic logging of the student's actions to investigate the student choices while performing analytical tasks. The experiment took advantage of an interactive learning platform--LearnWeb--that…

  7. Accelerated sea level rise and Florida Current transport

    Directory of Open Access Journals (Sweden)

    J. Park

    2015-07-01

    Full Text Available The Florida Current is the headwater of the Gulf Stream and is a component of the North Atlantic western boundary current from which a geostrophic balance between sea surface height and mass transport directly influence coastal sea levels along the Florida Straits. A linear regression of daily Florida Current transport estimates does not find a significant change in transport over the last decade; however, a nonlinear trend extracted from empirical mode decomposition (EMD suggests a 3 Sv decline in mean transport. This decline is consistent with observed tide gauge records in Florida Bay and the straits exhibiting an acceleration of mean sea level (MSL rise over the decade. It is not known whether this recent change represents natural variability or the onset of the anticipated secular decline in Atlantic meridional overturning circulation (AMOC; nonetheless, such changes have direct impacts on the sensitive ecological systems of the Everglades as well as the climate of western Europe and eastern North America.

  8. High performance predictive current control of a three phase VSI: An ...

    Indian Academy of Sciences (India)

    ... current control of a three phase VSI: An experimental assessment ... Voltage source inverter; two level inverter; predictive current control; weighting factor ... Conventionally, for reference current tracking control in a two level VSI, the objective ...

  9. Sputtering of sub-micrometer aluminum layers as compact, high-performance, light-weight current collector for supercapacitors

    Science.gov (United States)

    Busom, J.; Schreiber, A.; Tolosa, A.; Jäckel, N.; Grobelsek, I.; Peter, N. J.; Presser, V.

    2016-10-01

    Supercapacitors are devices for rapid and efficient electrochemical energy storage and commonly employ carbon coated aluminum foil as the current collector. However, the thickness of the metallic foil and the corresponding added mass lower the specific and volumetric performance on a device level. A promising approach to drastically reduce the mass and volume of the current collector is to directly sputter aluminum on the freestanding electrode instead of adding a metal foil. Our work explores the limitations and performance perspectives of direct sputter coating of aluminum onto carbon film electrodes. The tight and interdigitated interface between the metallic film and the carbon electrode enables high power handling, exceeding the performance and stability of a state-of-the-art carbon coated aluminum foil current collector. In particular, we find an enhancement of 300% in specific power and 186% in specific energy when comparing aluminum sputter coated electrodes with conventional electrodes with Al current collectors.

  10. Hybrid Direct Carbon Fuel Cell Performance with Anode Current Collector Material

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Kammer Hansen, Kent

    2015-01-01

    collectors were studied: Au, Ni, Ag, and Pt. It was shown that the performance of the direct carbon fuel cell (DCFC) is dependent on the current collector materials, Ni and Pt giving the best performance, due to their catalytic activity. Gold is suggested to be the best material as an inert current collector......The influence of the current collector on the performance of a hybrid direct carbon fuel cell (HDCFC), consisting of solid oxide fuel cell (SOFC) with a molten carbonate-carbon slurry in contact with the anode, has been investigated using current-voltage curves. Four different anode current...

  11. Technology Performance Level Assessment Methodology.

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Jesse D.; Bull, Diana L; Malins, Robert Joseph; Costello, Ronan Patrick; Aurelien Babarit; Kim Nielsen; Claudio Bittencourt Ferreira; Ben Kennedy; Kathryn Dykes; Jochem Weber

    2017-04-01

    The technology performance level (TPL) assessments can be applied at all technology development stages and associated technology readiness levels (TRLs). Even, and particularly, at low TRLs the TPL assessment is very effective as it, holistically, considers a wide range of WEC attributes that determine the techno-economic performance potential of the WEC farm when fully developed for commercial operation. The TPL assessment also highlights potential showstoppers at the earliest possible stage of the WEC technology development. Hence, the TPL assessment identifies the technology independent “performance requirements.” In order to achieve a successful solution, the entirety of the performance requirements within the TPL must be considered because, in the end, all the stakeholder needs must be achieved. The basis for performing a TPL assessment comes from the information provided in a dedicated format, the Technical Submission Form (TSF). The TSF requests information from the WEC developer that is required to answer the questions posed in the TPL assessment document.

  12. Motor current signature analysis for gearbox condition monitoring under transient speeds using wavelet analysis and dual-level time synchronous averaging

    Science.gov (United States)

    Bravo-Imaz, Inaki; Davari Ardakani, Hossein; Liu, Zongchang; García-Arribas, Alfredo; Arnaiz, Aitor; Lee, Jay

    2017-09-01

    This paper focuses on analyzing motor current signature for fault diagnosis of gearboxes operating under transient speed regimes. Two different strategies are evaluated, extensively tested and compared to analyze the motor current signature in order to implement a condition monitoring system for gearboxes in industrial machinery. A specially designed test bench is used, thoroughly monitored to fully characterize the experiments, in which gears in different health status are tested. The measured signals are analyzed using discrete wavelet decomposition, in different decomposition levels using a range of mother wavelets. Moreover, a dual-level time synchronous averaging analysis is performed on the same signal to compare the performance of the two methods. From both analyses, the relevant features of the signals are extracted and cataloged using a self-organizing map, which allows for an easy detection and classification of the diverse health states of the gears. The results demonstrate the effectiveness of both methods for diagnosing gearbox faults. A slightly better performance was observed for dual-level time synchronous averaging method. Based on the obtained results, the proposed methods can used as effective and reliable condition monitoring procedures for gearbox condition monitoring using only motor current signature.

  13. Sizing Performance of the Newly Developed Eddy Current System

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chan Hee; Lee, Hee Jong; Yoo, Hyun Ju; Moon, Gyoon Young; Lee, Tae Hoon [Korea Hydro and Nuclear Power Co., Ltd., Daejeon (Korea, Republic of)

    2013-10-15

    This paper describes the comparison results of sizing performance for two systems. The KHNP developed a new eddy current testing system for the inspection of steam generator tubing in domestic nuclear power plants. The equivalency assessment of the newly developed system with the EPRI-qualified system was already carried out. In this paper, the comparisons of depth-sizing performance for the artificial flaws between two systems were performed. The results show that the newly developed system is in good agreement with the qualified system. Therefore, it is expected that the newly developed eddy current system can be used for the inspection of steam generator tubing in nuclear power plants. There are some non-destructive examination (NDE) methods for the inspection of components in nuclear power plants, such as ultrasonic, radiographic, eddy current testing, etc. The eddy current testing is widely used for the inspection of steam generator (SG) tubing because it offers a relatively low cost approach for high speed, large scale testing of metallic materials in high pressure and temperature engineering systems. The Korea Hydro and Nuclear Power Co., Ltd. (KHNP) developed an eddy current testing system for the inspection of steam generator tubing in nuclear power plants. This system includes not only hardware but software such as the frequency generator and data acquisition-analysis program. The foreign eddy current system developed by ZETEC is currently used for the inspection of steam generator tubing in domestic nuclear power plants. The equivalency assessment between two systems was already carried out in accordance with the EPRI steam generator examination guidelines.

  14. Performance inspection of smart superconducting fault current controller in radial distribution substation through PSCAD/EMTDC simulation

    Energy Technology Data Exchange (ETDEWEB)

    MassoudiFarid, Mehrdad; Shin, Jae Woong; Lee, Ji Ho; Ko, Tae Kuk [Yonsei University, Seoul (Korea, Republic of)

    2013-12-15

    In power grid, in order to level out the generation with demand, up-gradation of the system is occasionally required. This will lead to more fault current levels. However, upgrading all the protection instruments of the system is both costly and extravagant. This issue could be dominated by using Smart Fault Current Controller (SFCC). While the impact of Fault current Limiters (FCL) in various locations has been studied in different situations for years, the performance of SFCC has not been investigated extensively. In this research, SFCC which has adopted the characteristics of a full bridge thyristor rectifier with a superconducting coil is applied to three main locations such as load feeder, Bus-tie position and main feeder location and its behavior is investigated through simulation in presence and absence of small Distributed Generation unit (DG). The results show a huge difference in limiting the fault current when using SFCC.

  15. Does social comparison make a difference? Optimism as a moderator of the relation between comparison level and academic performance

    NARCIS (Netherlands)

    Gibbons, FX; Blanton, H; Gerrard, M; Buunk, B; Eggleston, T

    Previous research has demonstrated that poor academic performance is associated with a downward shift in preferred level of academic comparison level (ACL). The current study assessed the long-term impact of this downward shift on the academic performance of college students and also examined the

  16. International co-ordinated research project on low and intermediate level waste package performance

    Energy Technology Data Exchange (ETDEWEB)

    Dayal, R. [International Atomic Energy Agency IAEA, Vienna (Austria)

    2001-07-01

    As part of IAEA's mandate to facilitate the transfer and exchange of information amongst Member States, the Agency is currently coordinating an international R and D project, involving 12 developed and developing countries, on Performance of Low and Intermediate Level Waste Packages under Disposal Conditions. This paper will review the current status of the Coordinated Research Project (CRP) and summarize the key findings of the work completed to date within the context of the CRP in the participating Member States. (author)

  17. International co-ordinated research project on low and intermediate level waste package performance

    International Nuclear Information System (INIS)

    Dayal, R.

    2001-01-01

    As part of IAEA's mandate to facilitate the transfer and exchange of information amongst Member States, the Agency is currently coordinating an international R and D project, involving 12 developed and developing countries, on Performance of Low and Intermediate Level Waste Packages under Disposal Conditions. This paper will review the current status of the Coordinated Research Project (CRP) and summarize the key findings of the work completed to date within the context of the CRP in the participating Member States. (author)

  18. Comparison of PI and PR current controllers applied on two-level VSC-HVDC transmission system

    DEFF Research Database (Denmark)

    Manoloiu, A.; Pereria, H.A.; Teodorescu, Remus

    2015-01-01

    This paper analyzes differences between αβ and dq reference frames regarding the control of two-level VSC-HVDC current loop and dc-link voltage outer loop. In the first part, voltage feedforward effect is considered with PI and PR controllers. In the second part, the feedforward effect is removed...... and the PR gains are tuned to keep the dynamic performance. Also, the power feedforward is removed and the outer loop PI controller is tuned in order to maintain the system dynamic performance. The paper is completed with simulation results, which highlight the advantages of using PR controller....

  19. (Biased) Grading of Students’ Performance: Students’ Names, Performance Level, and Implicit Attitudes

    Science.gov (United States)

    Bonefeld, Meike; Dickhäuser, Oliver

    2018-01-01

    Biases in pre-service teachers’ evaluations of students’ performance may arise due to stereotypes (e.g., the assumption that students with a migrant background have lower potential). This study examines the effects of a migrant background, performance level, and implicit attitudes toward individuals with a migrant background on performance assessment (assigned grades and number of errors counted in a dictation). Pre-service teachers (N = 203) graded the performance of a student who appeared to have a migrant background statistically significantly worse than that of a student without a migrant background. The differences were more pronounced when the performance level was low and when the pre-service teachers held relatively positive implicit attitudes toward individuals with a migrant background. Interestingly, only performance level had an effect on the number of counted errors. Our results support the assumption that pre-service teachers exhibit bias when grading students with a migrant background in a third-grade level dictation assignment. PMID:29867618

  20. (Biased Grading of Students’ Performance: Students’ Names, Performance Level, and Implicit Attitudes

    Directory of Open Access Journals (Sweden)

    Meike Bonefeld

    2018-05-01

    Full Text Available Biases in pre-service teachers’ evaluations of students’ performance may arise due to stereotypes (e.g., the assumption that students with a migrant background have lower potential. This study examines the effects of a migrant background, performance level, and implicit attitudes toward individuals with a migrant background on performance assessment (assigned grades and number of errors counted in a dictation. Pre-service teachers (N = 203 graded the performance of a student who appeared to have a migrant background statistically significantly worse than that of a student without a migrant background. The differences were more pronounced when the performance level was low and when the pre-service teachers held relatively positive implicit attitudes toward individuals with a migrant background. Interestingly, only performance level had an effect on the number of counted errors. Our results support the assumption that pre-service teachers exhibit bias when grading students with a migrant background in a third-grade level dictation assignment.

  1. Individual Performance Management: A Review of Current Practices

    Directory of Open Access Journals (Sweden)

    Ian O’ Boyle

    2013-05-01

    Full Text Available This paper provides a review of current practice in relation to individual performance management systems and process within the traditional business environment. There is a consensus that the role of the individual is central to the overall performance of any organization and how individual performances are managed and evaluated can have significant impacts on overall organizational success. Many organizations employ the traditional performance appraisal in order to monitor and assess individual employee performances. However, new approaches, such as 360-degree feedback have also become commonplace within the business environment. An analysis of each approach including benefits and challenges associated with each process is presented within this paper.

  2. Determination of deep levels in semi-insulating cadmium telluride by thermally stimulated current measurements

    International Nuclear Information System (INIS)

    Scharager, C.; Muller, J.C.; Stuck, R.; Siffert, P.

    1975-01-01

    Thermally stimulated current (TSC) measurements have been performed in high resistivity (rho approximately 10 7 ohms.cm) CdTe γ-ray detectors between 35 and 300K. The TSC curves have been analyzed by different methods, including those taking into account the retrapping of the carriers. The trap characteristics have been determined; especially three levels located at E(v)+0.13eV, E(v)+0.30eV and E(c)-0.55eV have been investigated [fr

  3. Loss of cultural world heritage and currently inhabited places to sea-level rise

    International Nuclear Information System (INIS)

    Marzeion, Ben; Levermann, Anders

    2014-01-01

    The world population is concentrated near the coasts, as are a large number of Cultural World Heritage sites, defined by the UNESCO. Using spatially explicit sea-level estimates for the next 2000 years and high-resolution topography data, we compute which current cultural heritage sites will be affected by sea-level rise at different levels of sustained future warming. As indicators for the pressure on future cultural heritage we estimate the percentage of each country’s area loss, and the percentage of current population living in regions that will be permanently below sea level, for different temperature levels. If the current global mean temperature was sustained for the next two millennia, about 6% (40 sites) of the UNESCO sites will be affected, and 0.7% of global land area will be below mean sea level. These numbers increase to 19% (136 sites) and 1.1% for a warming of 3 K. At this warming level, 3–12 countries will experience a loss of more than half of their current land surface, 25–36 countries lose at least 10% of their territory, and 7% of the global population currently lives in regions that will be below local sea level. Given the millennial scale lifetime of carbon dioxide in the atmosphere, our results indicate that fundamental decisions with regard to mankind’s cultural heritage are required. (paper)

  4. Enhanced performance of high current discharges in JET produced by ICRF heating during the current rise

    International Nuclear Information System (INIS)

    Bures, M.; Bhatnagar, V.; Christiansen, J.P.

    1989-01-01

    The performance of high current discharges can be improved by applying central ICRF heating before or shortly after the onset of sawtooth activity in the plasma current rise phase. Long sawtooth-free periods have been obtained which result in a transiently-enhanced discharge performance. High T c (0) = 9-10.5 keV with peaked profile T e (0)/ e > = 3-4 were obtained giving values of N e (0)T e (0) up to 6 x 10 20 (keV m -3 ). Improvements in T i (0) and neutron production are observed. A best value of n Dd (0)T i (0)τ E = 1.65 x 10 20 (m -3 keV s) was achieved. Local transport simulation shows that the electron and ion thermal diffusivities do not differ substantially in the two cases of current-rise (CR) and flat-top (FT) heating, the performance of the central plasma region being enhanced, in the case of current-rise, entirely by the elimination of the sawtooth instability. The maximum D-D reaction rate is enhanced by a factor of 2 compared to the flat-top value. An appreciable part of the reaction rate is attributed to 2nd harmonic deuterium (2ω CD ) heating. In all current-rise discharges radiation amounts to 25-50% of total power and Ζ eff remains roughly constant. (author)

  5. Performance assessment for low-level waste disposal in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Ashworth, A.B. [UK Dept. of the Environment, London (United Kingdom)

    1995-12-31

    British Nuclear Fuels plc (BNFL) operate a site for the disposal of Low Level Radioactive Waste at Drigg in West Cumbria, in North-West England. HMIP are responsible for the regulation of the site with regard to environmental discharges of radioactive materials, both operational and post-closure. This paper is concerned with post-closure matters only. Two post-closure performance assessments have been carried out for this site: one by the National Radiological Protection Board (NRPB) in 1987; and a subsequent one carried out on behalf of HMIP, completed in 1991. Currently, BNFL are preparing a Safety Case for continued operation of the Drigg site, and it expected that the core of this Case will comprise BNFL`s own analysis of post-closure performance. HMIP has developed procedures for the assessment of this Case, based upon experience of the previous Drigg assessments, and also upon the experience of similar work carried out in the assessment of Intermediate Level Waste (ILW) disposal at both deep and shallow potential sites. This paper describes the more important features of these procedures.

  6. The prediction of the hydrodynamic performance of tidal current turbines

    International Nuclear Information System (INIS)

    Xiao, B Y; Zhou, L J; Xiao, Y X; Wang, Z W

    2013-01-01

    Nowadays tidal current energy is considered to be one of the most promising alternative green energy resources and tidal current turbines are used for power generation. Prediction of the open water performance around tidal turbines is important for the reason that it can give some advice on installation and array of tidal current turbines. This paper presents numerical computations of tidal current turbines by using a numerical model which is constructed to simulate an isolated turbine. This paper aims at studying the installation of marine current turbine of which the hydro-environmental impacts influence by means of numerical simulation. Such impacts include free-stream velocity magnitude, seabed and inflow direction of velocity. The results of the open water performance prediction show that the power output and efficiency of marine current turbine varies from different marine environments. The velocity distribution should be clearly and the suitable unit installation depth and direction be clearly chosen, which can ensure the most effective strategy for energy capture before installing the marine current turbine. The findings of this paper are expected to be beneficial in developing tidal current turbines and array in the future

  7. Enhanced critical currents in (Gd,Y)Ba2Cu3Ox superconducting tapes with high levels of Zr addition

    Energy Technology Data Exchange (ETDEWEB)

    Selvamanickam, V; Chen, Y; Shi, T; Liu, Y; Khatri, ND; Liu, J; Yao, Y; Xiong, X; Lei, C; Soloveichik, S; Galstyan, E; Majkic, G

    2013-01-21

    The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba2Cu3Ox film. By a modified MOCVD process,enhanced critical current densities have been achieved with high levels of Zr addition,including 3.83 MA cm(-2) in 15 at.% Zr- added 1.1 mu m thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/ 12 mm have been reached in (Gd,Y) BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape,corresponding to a pinning force value of 268 GN m(-3). The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second- phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met.

  8. Enhanced critical currents in (Gd,Y)Ba2Cu3Ox superconducting tapes with high levels of Zr addition

    International Nuclear Information System (INIS)

    Selvamanickam, V; Shi, T; Liu, Y; Khatri, N D; Liu, J; Yao, Y; Galstyan, E; Majkic, G; Chen, Y; Xiong, X; Lei, C; Soloveichik, S

    2013-01-01

    The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba 2 Cu 3 O x film. By a modified MOCVD process, enhanced critical current densities have been achieved with high levels of Zr addition, including 3.83 MA cm −2 in 15 at.% Zr-added 1.1 μm thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/12 mm have been reached in (Gd,Y)BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape, corresponding to a pinning force value of 268 GN m −3 . The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second-phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met. (paper)

  9. Evaluating transient performance of servo mechanisms by analysing stator current of PMSM

    Science.gov (United States)

    Zhang, Qing; Tan, Luyao; Xu, Guanghua

    2018-02-01

    Smooth running and rapid response are the desired performance goals for the transient motions of servo mechanisms. Because of the uncertain and unobservable transient behaviour of servo mechanisms, it is difficult to evaluate their transient performance. Under the effects of electromechanical coupling, the stator current signals of a permanent-magnet synchronous motor (PMSM) potentially contain the performance information regarding servo mechanisms in use. In this paper, a novel method based on analysing the stator current of the PMSM is proposed for quantifying the transient performance. First, a vector control model is constructed to simulate the stator current behaviour in the transient processes of consecutive speed changes, consecutive load changes, and intermittent start-stops. It is discovered that the amplitude and frequency of the stator current are modulated by the transient load torque and motor speed, respectively. The stator currents under different performance conditions are also simulated and compared. Then, the stator current is processed using a local means decomposition (LMD) algorithm to extract the instantaneous amplitude and instantaneous frequency. The sample entropy of the instantaneous amplitude, which reflects the complexity of the load torque variation, is calculated as a performance indicator of smooth running. The peak-to-peak value of the instantaneous frequency, which defines the range of the motor speed variation, is set as a performance indicator of rapid response. The proposed method is applied to both simulated data in an intermittent start-stops process and experimental data measured for a batch of servo turrets for turning lathes. The results show that the performance evaluations agree with the actual performance.

  10. Current perspectives on performance assessment at the NRC

    International Nuclear Information System (INIS)

    Coplan, S.M.; Eisenberg, N.A.; Federline, M.V.; Randall, J.D.

    1992-01-01

    The Nuclear Regulatory Commission (NRC) staff is engaging in a number of activities involving performance assessment in order to support NRC's program in high-level waste management. Broad areas of activity include: (1) reactive work responding to products and activities of the Department of Energy (DOE), (2) proactive work, including development of an independent performance assessment capability, development of guidance for DOE, support for technical and programmatic integration, (3) a program of regulatory research, and (4) participation in a number of international activities. As the U.S. high-level waste program continues to mature, performance assessment is seen as playing a more prominent role in evaluating safety and focussing technical activities

  11. High-Level Synthesis: Productivity, Performance, and Software Constraints

    Directory of Open Access Journals (Sweden)

    Yun Liang

    2012-01-01

    Full Text Available FPGAs are an attractive platform for applications with high computation demand and low energy consumption requirements. However, design effort for FPGA implementations remains high—often an order of magnitude larger than design effort using high-level languages. Instead of this time-consuming process, high-level synthesis (HLS tools generate hardware implementations from algorithm descriptions in languages such as C/C++ and SystemC. Such tools reduce design effort: high-level descriptions are more compact and less error prone. HLS tools promise hardware development abstracted from software designer knowledge of the implementation platform. In this paper, we present an unbiased study of the performance, usability and productivity of HLS using AutoPilot (a state-of-the-art HLS tool. In particular, we first evaluate AutoPilot using the popular embedded benchmark kernels. Then, to evaluate the suitability of HLS on real-world applications, we perform a case study of stereo matching, an active area of computer vision research that uses techniques also common for image denoising, image retrieval, feature matching, and face recognition. Based on our study, we provide insights on current limitations of mapping general-purpose software to hardware using HLS and some future directions for HLS tool development. We also offer several guidelines for hardware-friendly software design. For popular embedded benchmark kernels, the designs produced by HLS achieve 4X to 126X speedup over the software version. The stereo matching algorithms achieve between 3.5X and 67.9X speedup over software (but still less than manual RTL design with a fivefold reduction in design effort versus manual RTL design.

  12. Instruction-level performance modeling and characterization of multimedia applications

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Y. [Los Alamos National Lab., NM (United States). Scientific Computing Group; Cameron, K.W. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Computer Science

    1999-06-01

    One of the challenges for characterizing and modeling realistic multimedia applications is the lack of access to source codes. On-chip performance counters effectively resolve this problem by monitoring run-time behaviors at the instruction-level. This paper presents a novel technique of characterizing and modeling workloads at the instruction level for realistic multimedia applications using hardware performance counters. A variety of instruction counts are collected from some multimedia applications, such as RealPlayer, GSM Vocoder, MPEG encoder/decoder, and speech synthesizer. These instruction counts can be used to form a set of abstract characteristic parameters directly related to a processor`s architectural features. Based on microprocessor architectural constraints and these calculated abstract parameters, the architectural performance bottleneck for a specific application can be estimated. Meanwhile, the bottleneck estimation can provide suggestions about viable architectural/functional improvement for certain workloads. The biggest advantage of this new characterization technique is a better understanding of processor utilization efficiency and architectural bottleneck for each application. This technique also provides predictive insight of future architectural enhancements and their affect on current codes. In this paper the authors also attempt to model architectural effect on processor utilization without memory influence. They derive formulas for calculating CPI{sub 0}, CPI without memory effect, and they quantify utilization of architectural parameters. These equations are architecturally diagnostic and predictive in nature. Results provide promise in code characterization, and empirical/analytical modeling.

  13. Evidence of transcranial direct current stimulation-generated electric fields at subthalamic level in human brain in vivo.

    Science.gov (United States)

    Chhatbar, Pratik Y; Kautz, Steven A; Takacs, Istvan; Rowland, Nathan C; Revuelta, Gonzalo J; George, Mark S; Bikson, Marom; Feng, Wuwei

    2018-03-13

    Transcranial direct current stimulation (tDCS) is a promising brain modulation technique for several disease conditions. With this technique, some portion of the current penetrates through the scalp to the cortex and modulates cortical excitability, but a recent human cadaver study questions the amount. This insufficient intracerebral penetration of currents may partially explain the inconsistent and mixed results in tDCS studies to date. Experimental validation of a transcranial alternating current stimulation-generated electric field (EF) in vivo has been performed on the cortical (using electrocorticography, ECoG, electrodes), subcortical (using stereo electroencephalography, SEEG, electrodes) and deeper thalamic/subthalamic levels (using DBS electrodes). However, tDCS-generated EF measurements have never been attempted. We aimed to demonstrate that tDCS generates biologically relevant EF as deep as the subthalamic level in vivo. Patients with movement disorders who have implanted deep brain stimulation (DBS) electrodes serve as a natural experimental model for thalamic/subthalamic recordings of tDCS-generated EF. We measured voltage changes from DBS electrodes and body resistance from tDCS electrodes in three subjects while applying direct current to the scalp at 2 mA and 4 mA over two tDCS montages. Voltage changes at the level of deep nuclei changed proportionally with the level of applied current and varied with different tDCS montages. Our findings suggest that scalp-applied tDCS generates biologically relevant EF. Incorporation of these experimental results may improve finite element analysis (FEA)-based models. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Current Approaches to Tactical Performance Analyses in Soccer Using Position Data.

    Science.gov (United States)

    Memmert, Daniel; Lemmink, Koen A P M; Sampaio, Jaime

    2017-01-01

    Tactical match performance depends on the quality of actions of individual players or teams in space and time during match-play in order to be successful. Technological innovations have led to new possibilities to capture accurate spatio-temporal information of all players and unravel the dynamics and complexity of soccer matches. The main aim of this article is to give an overview of the current state of development of the analysis of position data in soccer. Based on the same single set of position data of a high-level 11 versus 11 match (Bayern Munich against FC Barcelona) three different promising approaches from the perspective of dynamic systems and neural networks will be presented: Tactical performance analysis revealed inter-player coordination, inter-team and inter-line coordination before critical events, as well as team-team interaction and compactness coefficients. This could lead to a multi-disciplinary discussion on match analyses in sport science and new avenues for theoretical and practical implications in soccer.

  15. Enhanced performance on high current discharges in JET produced by ICRF heating during the current rise

    International Nuclear Information System (INIS)

    Bures, M.; Bhatnagar, V.; Cotrell, G.; Corti, S.; Christiansen, J.P.; Hellsten, T.; Jacquinot, J.; Lallia, P.; Lomas, P.; O'Rourke, J.; Taroni, A.; Tibone, F.; Start, D.F.H.

    1989-01-01

    The performance of high current discharges can be increased by applying central ICRF heating before or shortly after the onset of sawtooth activity in the plasma current rise phase. Sawtooth-free periods have been obtained resulting in the enhanced discharge performance. High T e (0) 9 - 10.5 keV with peaked profiles T e (0)/ e > = 3 - 4 were obtained giving values of n e (0)T e (0) up to 6x10 20 (keV m -3 ). Improvements in T i (0) and neutron production are observed. A 60 % enhancement in D-D reaction rate from 2nd harmonic deuterium (2ω CD ) heating appears to be present. In all current rise (CR) discharges radiation amounts to 25-50 % of total power. (author) 4 refs., 6 figs

  16. Canyon of current suppression in an interacting two-level quantum dot

    DEFF Research Database (Denmark)

    Karlström, O; Pedersen, Jonas Nyvold; Samuelsson, P

    2011-01-01

    Motivated by the recent discovery of a canyon of conductance suppression in a two-level equal-spin quantum dot system [Phys. Rev. Lett. 104, 186804 (2010)], the transport through this system is studied in detail. At low bias and low temperature a strong current suppression is found around...... the electron-hole symmetry point independent of the couplings, in agreement with previous results. By means of a Schrieffer–Wolff transformation we are able to give an intuitive explanation to this suppression in the low-energy regime. In the general situation, numerical simulations are carried out using...... for the current suppression. It is also shown how broadening, interference, and a finite interaction energy cause a shift of the current minimum away from degeneracy. Finally we see how an increased population of the upper level leads to current peaks on each side of the suppression line. At sufficiently high...

  17. Eddy current NDE performance demonstrations using simulation tools

    International Nuclear Information System (INIS)

    Maurice, L.; Costan, V.; Guillot, E.; Thomas, P.

    2013-01-01

    To carry out performance demonstrations of the Eddy-Current NDE processes applied on French nuclear power plants, EDF studies the possibility of using simulation tools as an alternative to measurements on steam generator tube mocks-up. This paper focuses on the strategy led by EDF to assess and use code C armel3D and Civa, on the case of Eddy-Current NDE on wears problem which may appear in the U-shape region of steam generator tubes due to the rubbing of anti-vibration bars.

  18. Hanford low-level tank waste interim performance assessment

    International Nuclear Information System (INIS)

    Mann, F.M.

    1997-01-01

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and performance early in the disposal system project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives

  19. PERFORMANCE DETERMINANTS OF PARTICIPATION BANKS: THE ROLE OF SPECIAL CURRENT ACCOUNTS

    Directory of Open Access Journals (Sweden)

    Yusuf DINÇ

    2017-02-01

    Full Text Available Participation banks collect participation funds for credit allocation by participation accounts and special current accounts as main function. Profit or loss offered to participation accounts on base of participation share ratio while special current accounts are considered as cost-free resources. Participation funds are used in the models that analyze participation banks’ performance. Although participation fund types are not considered as variables also special current accounts. This research brings suggestions for the variables for performance analysis of participation banks for further researches.

  20. Genetics and sport performance: current challenges and directions to the future

    Directory of Open Access Journals (Sweden)

    João Paulo Limongi França GUILHERME

    2014-03-01

    Full Text Available In recent years there has been a great progress in molecular biology techniques, which has facilitated the researches on influence of genetics on human performance. There are specific regions of DNA that can vary between individuals. Such variations (i.e., polymorphisms may, in part, explain why some individuals have differentiated responses to certain stimuli, including the responses to sports training. In a particular sport, the presence of specific polymorphisms may contribute to high levels of performance. Since 1998, several polymorphisms have been associated with athletic phenotypes; however the accumulation of information generated over these 15 years shows that the influence of genetics to sport is extremely complex. In this review, we will summarise the current status of the field, discussing the implications of available knowledge for the practice of professionals involved with the sport and suggesting future directions for research. We also discuss topics related to the importance of polygenic profile characterization of athletes, methods for the identification of new polymorphisms associated with physical performance, the use of genetic testing for predicting competitive success, and how crucial is the genetic profile for the success athletes in competition.

  1. Performance of the CMS High Level Trigger

    CERN Document Server

    Perrotta, Andrea

    2015-01-01

    The CMS experiment has been designed with a 2-level trigger system. The first level is implemented using custom-designed electronics. The second level is the so-called High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. For Run II of the Large Hadron Collider, the increases in center-of-mass energy and luminosity will raise the event rate to a level challenging for the HLT algorithms. The increase in the number of interactions per bunch crossing, on average 25 in 2012, and expected to be around 40 in Run II, will be an additional complication. We present here the expected performance of the main triggers that will be used during the 2015 data taking campaign, paying particular attention to the new approaches that have been developed to cope with the challenges of the new run. This includes improvements in HLT electron and photon reconstruction as well as better performing muon triggers. We will also present the performance of the improved trac...

  2. The design of high performance weak current integrated amplifier

    International Nuclear Information System (INIS)

    Chen Guojie; Cao Hui

    2005-01-01

    A design method of high performance weak current integrated amplifier using ICL7650 operational amplifier is introduced. The operating principle of circuits and the step of improving amplifier's performance are illustrated. Finally, the experimental results are given. The amplifier has programmable measurement range of 10 -9 -10 -12 A, automatic zero-correction, accurate measurement, and good stability. (authors)

  3. Current status of low-level-waste-segregation technology

    International Nuclear Information System (INIS)

    Clark, D.E.; Colombo, P.; Sailor, V.L.

    1982-01-01

    The adoption of improved waste segregation practices by waste generators and burial sites will result in the improved disposal of low-level wastes (LLW) in the future. Many of the problems connected with this disposal mode are directly attributable to or aggravated by the indiscriminate mixing of various waste types in burial trenches. Thus, subsidence effects, contact with ground fluids, movement of radioactivity in the vapor phase, migration of radionuclides due to the presence of chelating agents or products of biological degradation, deleterious chemical reactions, and other problems have occurred. Regulations are currently being promulgated which will require waste segregation to a high degree at LLW burial sites. The state-of-the-art of LLW segregation technology and current practices in the USA have been surveyed at representative facilities. Favorable experience has been reported at various sites following the application of segregation controls. This paper reports on the state-of-the-art survey and addresses current and projected LLW segregation practices and their relationship to other waste management activities

  4. Performance of engineered barriers for low-level waste

    International Nuclear Information System (INIS)

    Taplin, D.; Claridge, F.B.

    1987-09-01

    Geotechnical Resources Ltd., in association with Komex Consultants Ltd., was retained to collect, synthesize and evaluate the available information on the long term performance of engineered barriers for low-level radioactive wastes disposed in Canada. Literature was researched from Canadian, United States and European sources. A variety of barrier materials were assessed in the study and included natural clays, concrete and cement, metals, bentonite-sand admixes, bitumen and bituminous admixes, soil cement and polymeric membranes. The generalized geological and geotechnical conditions encountered within the soil and rock host media currently under consideration for disposal sites in southern Ontario were also summarized. Both internal barriers, or buffers, to immobilize the waste material and reduce radionuclide mobility, as well as external barriers to limit the migration of contaminants were examined. Microbial activities within the waste forms were analyzed, including cellulose degradation, methanogenesis and bicarbonate and organic reactions. Microbial interactions with the various engineered barrier materials under consideration were also assessed. Finally, the anticipated long term performances of the respective barrier materials under consideration were evaluated, along with the general suitability of the geological host media being proposed for disposal sites

  5. Admission Math Level and Student Performance

    DEFF Research Database (Denmark)

    la Cour, Lisbeth

    2015-01-01

    In this paper we analyze the study performance data for three cohorts of students for the course in Economics at the Business Diploma (herafter HD) study program at Copenhagen Business School. Out main findings are 1) that students with the lowest level of math from high school are performing worse...

  6. Hierarchically Mesostructured Aluminum Current Collector for Enhancing the Performance of Supercapacitors.

    Science.gov (United States)

    Huang, Yilun; Li, Yuyao; Gong, Qianming; Zhao, Guanlei; Zheng, Pengjie; Bai, Junfei; Gan, Jianning; Zhao, Ming; Shao, Yang; Wang, Dazhi; Liu, Lei; Zou, Guisheng; Zhuang, Daming; Liang, Ji; Zhu, Hongwei; Nan, Cewen

    2018-05-16

    Aluminum (Al) current collector is one of the most important components of supercapacitors, and its performance has vital effects on the electrochemical performance and cyclic stability of supercapacitors. In the present work, a scalable and low-cost, yet highly efficient, picosecond laser processing method of Al current collectors was developed to improve the overall performance of supercapacitors. The laser treatment resulted in hierarchical micro-nanostructures on the surface of the commercial Al foil and reduced the surface oxygen content of the foil. The electrochemical performance of the Al foil with the micro-nanosurface structures was examined in the symmetrical activated carbon-based coin supercapacitors with an organic electrolyte. The results suggest that the laser-treated Al foil (laser-Al) increased the capacitance density of supercapacitors up to 110.1 F g -1 and promoted the rate capability due to its low contact resistance with the carbonaceous electrode and high electrical conductivity derived from its larger specific surface areas and deoxidized surface. In addition, the capacitor with the laser-Al current collector exhibited high cyclic stability with 91.5% capacitance retention after 10 000 cycles, 21.3% higher than that with pristine-Al current collector due to its stronger bonding with the carbonaceous electrode that prevented any delamination during aging. Our work has provided a new strategy for improving the electrochemical performance of supercapacitors.

  7. Periodically Swapping Modulation (PSM) Strategy for Three-Level (TL) DC/DC Converter with Balanced Switch Currents

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Zhang, Qi

    2018-01-01

    The asymmetrical modulation strategy is widely used in various types of three-level (TL) DC/DC converters, while the current imbalance among the power switches is one of the important issues. In this paper, a novel periodically swapping modulation (PSM) strategy is proposed for balancing the power...... switches’ currents in various types of TL DC/DC converters. In the proposed PSM strategy, the driving signals of the switch pairs are swapped periodically, which guarantees that the currents through the power switches are kept balanced in every two switching periods. Therefore, the proposed PSM...... strategy can effectively improve the reliability of the converter by balancing the power losses and thermal stresses among the power switches. The operation principle and performances of the proposed PSM strategy are analyzed in detail. Finally, the simulation and experimental results are presented...

  8. Evaluation on current-limiting performance of the YBCO thin-film wire considering electric coupling condition

    International Nuclear Information System (INIS)

    Du, H.-I.; Han, B.-S.; Kim, Y.-J.; Lee, D.-H.; Song, S.-S.; Han, T.-H.; Han, S.-C.

    2011-01-01

    The basic way to improve the performance of a superconducting current limiter is to apply and evaluate a superconducting device that is appropriate to the superconducting current limiter. Among the many types of superconducting devices, the YBCO thin film wire has excellent current-limiting performance that is appropriate for actual system application. For the application of the YBCO thin film wire to superconducting current limiters, its current-limiting performance as a unit device must be accurately evaluated, and measures to improve its current-limiting performance must be sought. Accordingly, to evaluate the current-limiting performance of the YBCO thin film wire, this study was conducted to evaluate its resistance-increasing trend, V max , T r , I max , I qt , and current-limiting rate as a unit device, after which the electric coupling condition that consists of a core and windings was used to evaluate the current-limiting performance of the YBCO thin film wire.

  9. 45 CFR 305.40 - Penalty performance measures and levels.

    Science.gov (United States)

    2010-10-01

    ... HUMAN SERVICES PROGRAM PERFORMANCE MEASURES, STANDARDS, FINANCIAL INCENTIVES, AND PENALTIES § 305.40 Penalty performance measures and levels. (a) There are three performance measures for which States must... 45 Public Welfare 2 2010-10-01 2010-10-01 false Penalty performance measures and levels. 305.40...

  10. Performance of a methane-fueled single-cell SOFC stack at various levels of fuel utilization

    International Nuclear Information System (INIS)

    Ahmed, K.; Bolden, R.; Ramprakash and Foger, K.

    1998-01-01

    Fuel-gas mixtures representing 10 to 85% utilization of a methane-steam mixture at S/C=2 were fed to a single cell stack with a Ni-based anode at 875 deg C. Cell voltage and power output were recorded at current densities of 50 to 350 mA/cm 2 . The accompanying anode off-gas composition at some of these conditions were measured using on-line gas chromatograph and compared with the compositions predicted by a thermodynamic model based on the assumption of no carbon formation. Electrical losses were measured at a chosen current density at various levels of fuel utilization by the galvanostatic current-interruption technique. Cell voltage stability was monitored for up to 1000 h at two levels of fuel utilization. The stack performance was simulated using a mathematical model of the stack; the simulations were compared with the stack test data. Copyright (1998) Australasian Ceramic Society

  11. ESTIMATING HIGH LEVEL WASTE MIXING PERFORMANCE IN HANFORD DOUBLE SHELL TANKS

    International Nuclear Information System (INIS)

    Thien, M.G.; Greer, D.A.; Townson, P.

    2011-01-01

    The ability to effectively mix, sample, certify, and deliver consistent batches of high level waste (HLW) feed from the Hanford double shell tanks (DSTs) to the Waste Treatment and Immobilization Plant (WTP) presents a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. The Department of Energy's (DOE's) Tank Operations Contractor (TOC), Washington River Protection Solutions (WRPS) is currently demonstrating mixing, sampling, and batch transfer performance in two different sizes of small-scale DSTs. The results of these demonstrations will be used to estimate full-scale DST mixing performance and provide the key input to a programmatic decision on the need to build a dedicated feed certification facility. This paper discusses the results from initial mixing demonstration activities and presents data evaluation techniques that allow insight into the performance relationships of the two small tanks. The next steps, sampling and batch transfers, of the small scale demonstration activities are introduced. A discussion of the integration of results from the mixing, sampling, and batch transfer tests to allow estimating full-scale DST performance is presented.

  12. A three-level framework for performance-based railway timetabling

    DEFF Research Database (Denmark)

    Goverde, Rob M P; Bešinović, Nikola; Binder, Anne

    2016-01-01

    . This paper presents a performance-based railway timetabling framework integrating timetable construction and evaluation on three levels: microscopic, macroscopic, and a corridor fine-tuning level, where each performance indicator is optimized or evaluated at the appropriate level. A modular implementation...

  13. Cross-Circulating Current Suppression Method for Parallel Three-Phase Two-Level Inverters

    DEFF Research Database (Denmark)

    Wei, Baoze; Guerrero, Josep M.; Guo, Xiaoqiang

    2015-01-01

    The parallel architecture is very popular for power inverters to increase the power level. This paper presents a method for the parallel operation of inverters in an ac-distributed system, to suppress the cross-circulating current based on virtual impedance without current-sharing bus...

  14. Learning from Performance Feedback: Performance Information, Aspiration Levels, and Managerial Priorities

    DEFF Research Database (Denmark)

    Nielsen, Poul Aaes

    2014-01-01

    . This article adapts this model to a public sector context and tests one implication of the model, namely that public managers will increase their prioritization of goals that are currently performing below aspirations. This is a central question to the study of public organizations pursuing multiple...

  15. Unreviewed Disposal Question Evaluation: Impact of New Information since 2008 PA on Current Low-Level Solid Waste Operations

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G.; Smith, F.; Hamm, L.; Butcher, T.

    2014-10-06

    Solid low-level waste disposal operations are controlled in part by an E-Area Low-Level Waste Facility (ELLWF) Performance Assessment (PA) that was completed by the Savannah River National Laboratory (SRNL) in 2008 (WSRC 2008). Since this baseline analysis, new information pertinent to disposal operations has been identified as a natural outcome of ongoing PA maintenance activities and continuous improvement in model simulation techniques (Flach 2013). An Unreviewed Disposal Question (UDQ) Screening (Attachment 1) has been initiated regarding the continued ability of the ELLWF to meet Department of Energy (DOE) Order 435.1 performance objectives in light of new PA items and data identified since completion of the original UDQ Evaluation (UDQE). The present UDQE assesses the ability of Solid Waste (SW) to meet performance objectives by estimating the influence of new information items on a recent sum-of-fractions (SOF) snapshot for each currently active E-Area low-level waste disposal unit. A final SOF, as impacted by this new information, is projected based on the assumptions that the current disposal limits, Waste Information Tracking System (WITS) administrative controls, and waste stream composition remain unchanged through disposal unit operational closure (Year 2025). Revision 1 of this UDQE addresses the following new PA items and data identified since completion of the original UDQE report in 2013: New Kd values for iodine, radium and uranium; Elimination of cellulose degradation product (CDP) factors; Updated radionuclide data; Changes in transport behavior of mobile radionuclides; Potential delay in interim closure beyond 2025; and Component-in-grout (CIG) plume interaction correction. Consideration of new information relative to the 2008 PA baseline generally indicates greater confidence that PA performance objectives will be met than indicated by current SOF metrics. For SLIT9, the previous prohibition of non-crushable containers in revision 0

  16. Level-1 $\\tau$ trigger performance in 2017 data

    CERN Document Server

    CMS Collaboration

    2018-01-01

    In 2017, the LHC achieved an instantaneous luminosity of 2.06x10$^{34}$cm$^{-2}$s$^{-1}$, and a peak average pile-up of more than 50. This document describes the performance of the CMS Level-1 calorimeter trigger for $\\tau$ leptons using 40.9 fb$^{-1}$ of 2017 data. Details of the Level-1 trigger algorithms can be found in CMS-DP-2015-009. The previous Level-1 $\\tau$ performance report can be found in CMS-DP-2017-022.

  17. A ZVS PWM control strategy with balanced capacitor current for half-bridge three-level DC/DC converter

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Chen, Zhe

    2017-01-01

    The capacitor current would be imbalanced under the conventional control strategy in the half-bridge three-level (HBTL) DC/DC converter due to the effect of the output inductance of the power supply and the input line inductance, which would affect the converter's reliability. This paper proposes...... a pulse-wide modulation (PWM) strategy composed of two operation modes for the HBTL DC/DC converter, which can realize the zero-voltage switching (ZVS) for the efficiency improvement. In addition, a capacitor current balancing control is proposed by alternating the two operation modes of the proposed ZVS...... PWM strategy, which can eliminate the current imbalance among the two input capacitors. Therefore, the proposed control strategy can improve the converter's performance and reliability in: 1) reducing the switching losses and noises of the power switches; 2) balancing the thermal stresses...

  18. Cost-optimal levels for energy performance requirements

    DEFF Research Database (Denmark)

    Thomsen, Kirsten Engelund; Aggerholm, Søren; Kluttig-Erhorn, Heike

    2011-01-01

    The CA conducted a study on experiences and challenges for setting cost optimal levels for energy performance requirements. The results were used as input by the EU Commission in their work of establishing the Regulation on a comparative methodology framework for calculating cost optimal levels...... of minimum energy performance requirements. In addition to the summary report released in August 2011, the full detailed report on this study is now also made available, just as the EC is about to publish its proposed Regulation for MS to apply in their process to update national building requirements....

  19. Low-level radioactive waste disposal in the United States: An overview of current commercial regulations and concepts

    International Nuclear Information System (INIS)

    Kennedy, W.E. Jr.

    1993-08-01

    Commercial low-level radioactive waste disposal in the United States is regulated by the US Nuclear Regulatory Commission (NRC) under 10 CFR 61 (1991). This regulation was issued in 1981 after a lengthy and thorough development process that considered the radionuclide concentrations and characteristics associated with commercial low-level radioactive waste streams; alternatives for waste classification; alternative technologies for low-level radioactive waste disposal; and data, modeling, and scenario analyses. The development process also included the publication of both draft and final environmental impact statements. The final regulation describes the general provisions; licenses; performance objectives; technical requirements for land disposal; financial assurances; participation by state governments and Indian tribes; and records, reports, tests, and inspections. This paper provides an overview of, and tutorial on, current commercial low-level radioactive waste disposal regulations in the United States

  20. Modeling take-over performance in level 3 conditionally automated vehicles.

    Science.gov (United States)

    Gold, Christian; Happee, Riender; Bengler, Klaus

    2017-11-28

    Taking over vehicle control from a Level 3 conditionally automated vehicle can be a demanding task for a driver. The take-over determines the controllability of automated vehicle functions and thereby also traffic safety. This paper presents models predicting the main take-over performance variables take-over time, minimum time-to-collision, brake application and crash probability. These variables are considered in relation to the situational and driver-related factors time-budget, traffic density, non-driving-related task, repetition, the current lane and driver's age. Regression models were developed using 753 take-over situations recorded in a series of driving simulator experiments. The models were validated with data from five other driving simulator experiments of mostly unrelated authors with another 729 take-over situations. The models accurately captured take-over time, time-to-collision and crash probability, and moderately predicted the brake application. Especially the time-budget, traffic density and the repetition strongly influenced the take-over performance, while the non-driving-related tasks, the lane and drivers' age explained a minor portion of the variance in the take-over performances. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. High performance current controller for particle accelerator magnets supply

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Bidoggia, Benoit; Munk-Nielsen, Stig

    2013-01-01

    The electromagnets in modern particle accelerators require high performance power supply whose output is required to track the current reference with a very high accuracy (down to 50 ppm). This demands very high bandwidth controller design. A converter based on buck converter topology is used...

  2. Performance demonstration requirements for eddy current steam generator tube inspection

    International Nuclear Information System (INIS)

    Kurtz, R.J.; Heasler, P.G.; Anderson, C.M.

    1992-10-01

    This paper describes the methodology used for developing performance demonstration tests for steam generator tube eddy current (ET) inspection systems. The methodology is based on statistical design principles. Implementation of a performance demonstration test based on these design principles will help to ensure that field inspection systems have a high probability of detecting and correctly sizing tube degradation. The technical basis for the ET system performance thresholds is presented. Probability of detection and flaw sizing tests are described

  3. High performance current generator with one-picoampere resolution

    International Nuclear Information System (INIS)

    Grillo, L.; Manfredi, P.F.; Marchesini, R.

    1975-01-01

    A high-performance current generator for the picoampere region is presented. Although it was primarily developed as a part of an automatic test system to calibrate charge integrators for accelerating machines. It can suit a wide range of applications. It consists basically of a positive feedback loop of controlled gain which includes a varactor bridge operational amplifier. The essential features of the instrument are a 1 pA resolution and a 10 15 Ω output impedance. The output is guarded and floating between - 120 V and + 120 V, and the voltage across the external loads is measured without affecting the delivered current by a digital panel meter on the front panel. The unit can therefore operate as a high-accuracy dc impedance meter. (Auth.)

  4. Performance of Virtual Current Meters in Hydroelectric Turbine Intakes

    Energy Technology Data Exchange (ETDEWEB)

    Harding, Samuel F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group; Romero-Gomez, Pedro D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group; Richmond, Marshall C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group

    2016-04-30

    Standards provide recommendations for the best practices in the installation of current meters for measuring fluid flow in closed conduits. These include PTC-18 and IEC-41 . Both of these standards refer to the requirements of the ISO Standard 3354 for cases where the velocity distribution is assumed to be regular and the flow steady. Due to the nature of the short converging intakes of Kaplan hydroturbines, these assumptions may be invalid if current meters are intended to be used to characterize turbine flows. In this study, we examine a combination of measurement guidelines from both ISO standards by means of virtual current meters (VCM) set up over a simulated hydroturbine flow field. To this purpose, a computational fluid dynamics (CFD) model was developed to model the velocity field of a short converging intake of the Ice Harbor Dam on the Snake River, in the State of Washington. The detailed geometry and resulting wake of the submersible traveling screen (STS) at the first gate slot was of particular interest in the development of the CFD model using a detached eddy simulation (DES) turbulence solution. An array of virtual point velocity measurements were extracted from the resulting velocity field to simulate VCM at two virtual measurement (VM) locations at different distances downstream of the STS. The discharge through each bay was calculated from the VM using the graphical integration solution to the velocity-area method. This method of representing practical velocimetry techniques in a numerical flow field has been successfully used in a range of marine and conventional hydropower applications. A sensitivity analysis was performed to observe the effect of the VCM array resolution on the discharge error. The downstream VM section required 11–33% less VCM in the array than the upstream VM location to achieve a given discharge error. In general, more instruments were required to quantify the discharge at high levels of accuracy when the STS was

  5. Daily micro-breaks and job performance: General work engagement as a cross-level moderator.

    Science.gov (United States)

    Kim, Sooyeol; Park, YoungAh; Headrick, Lucille

    2018-03-29

    Despite the growing research on work recovery and its well-being outcomes, surprisingly little attention has been paid to at-work recovery and its job performance outcomes. The current study extends the work recovery literature by examining day-level relationships between prototypical microbreaks and job performance as mediated by state positive affect. Furthermore, general work engagement is tested as a cross-level moderator weakening the indirect effects of microbreaks on job performance via positive affect. Using multisource experience sampling method, the authors collected two daily surveys from 71 call center employees and obtained objective records of daily sales performance for two consecutive weeks (n = 632). Multilevel path analysis results showed that relaxation, socialization, and cognitive microbreaks were related to increased positive affect at work which, in turn, predicted greater sales performance. However, breaks for nutrition-intake (having snacks and drinks) did not show significant effects. Importantly, microbreaks had significant indirect effects on job performance via positive affect only for workers who had lower general work engagement, whereas the indirect effects did not exist for workers who had higher general work engagement. Furthermore, Bayesian multilevel analyses confirmed the results. Theoretical and practical implications, limitations, and future research directions are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  6. Guidelines for radiological performance assessment of DOE low-level radioactive waste disposal sites

    International Nuclear Information System (INIS)

    Case, M.J.; Otis, M.D.

    1988-07-01

    This document provides guidance for conducting radiological performance assessments of Department of Energy (DOE) low-level radioactive waste (LLW) disposal facilities. The guidance is specifically intended to provide the fundamental approach necessary to meet the performance assessment requirements. The document is written for LLW facility operators or other personnel who will manage the performance assessment task. The document is meant to provide guidance for conducting performance assessments in a generally consistent manner at all DOE LLW disposal facilities. The guidance includes a summary of performance objectives to be met by LLW disposal facilities (these objectives are derived from current DOE and other applicable federal regulatory guidelines); specific criteria for an adequate performance assessment and from which a minimum set of required calculations may be determined; recommendations of methods for screening critical components of the analysis system so that these components can be addressed in detail; recommendations for the selection of existing models and the development of site-specific models; recommendations of techniques for comparison of assessment results with performance objectives; and a summary of reporting requirements

  7. Comparison of energy performance requirements levels

    DEFF Research Database (Denmark)

    Spiekman, Marleen; Thomsen, Kirsten Engelund; Rose, Jørgen

    This summary report provides a synthesis of the work within the EU SAVE project ASIEPI on developing a method to compare the energy performance (EP) requirement levels among the countries of Europe. Comparing EP requirement levels constitutes a major challenge. From the comparison of for instance...... the present Dutch requirement level (EPC) of 0,8 with the present Flemish level of E80, it can easily be seen that direct comparison is not possible. The conclusions and recommendations of the study are presented in part A. These constitute the most important result of the project. Part B gives an overview...... of all other project material related to that topic, which allows to easily identify the most pertinent information. Part C lists the project partners and sponsors....

  8. Back-to-back three-level converter controlled by a novel space-vector hysteresis current control for wind conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Ghennam, Tarak [Laboratoire d' Electronique de Puissance (LEP), UER: Electrotechnique, Ecole Militaire Polytechnique d' Alger, BP 17, Bordj EL Bahri, Alger (Algeria); Berkouk, El-Madjid [Laboratoire de Commande des Processus (LCP), Ecole Nationale Polytechnique d' Alger, BP 182, 10 avenue Hassen Badi, 16200 el Harrach (Algeria)

    2010-04-15

    In this paper, a novel space-vector hysteresis current control (SVHCC) is proposed for a back-to-back three-level converter which is used as an electronic interface in a wind conversion system. The proposed SVHCC controls the active and reactive powers delivered to the grid by the doubly fed induction machine (DFIM) through the control of its rotor currents. In addition, it controls the neutral point voltage by using the redundant inverter switching states. The three rotor current errors are gathered into a single space-vector quantity. The magnitude of the error vector is limited within boundary areas of a square shape. The control scheme is based firstly on the detection of the area and sector in which the vector tip of the current error can be located. Then, an appropriate voltage vector among the 27 voltage vectors of the three-level voltage source inverter (VSI) is applied to push the error vector towards the hysteresis boundaries. Simple look-up tables are required for the area and sector detection, and also for vector selection. The performance of the proposed control technique has been verified by simulations. (author)

  9. Nuisance levels of noise effects radiologists' performance

    Science.gov (United States)

    McEntee, Mark F.; Coffey, Amina; Ryan, John; O'Beirne, Aaron; Toomey, Rachel; Evanoff, Micheal; Manning, David; Brennan, Patrick C.

    2010-02-01

    This study aimed to measure the sound levels in Irish x-ray departments. The study then established whether these levels of noise have an impact on radiologists performance Noise levels were recorded 10 times within each of 14 environments in 4 hospitals, 11 of which were locations where radiologic images are judged. Thirty chest images were then presented to 26 senior radiologists, who were asked to detect up to three nodular lesions within 30 posteroanterior chest x-ray images in the absence and presence of noise at amplitude demonstrated in the clinical environment. The results demonstrated that noise amplitudes rarely exceeded that encountered with normal conversation with the maximum mean value for an image-viewing environment being 56.1 dB. This level of noise had no impact on the ability of radiologists to identify chest lesions with figure of merits of 0.68, 0.69, and 0.68 with noise and 0.65, 0.68, and 0.67 without noise for chest radiologists, non-chest radiologists, and all radiologists, respectively. the difference in their performance using the DBM MRMC method was significantly better with noise than in the absence of noise at the 90% confidence interval (p=0.077). Further studies are required to establish whether other aspects of diagnosis are impaired such as recall and attention and the effects of more unexpected noise on performance.

  10. Wafer-level radiometric performance testing of uncooled microbolometer arrays

    Science.gov (United States)

    Dufour, Denis G.; Topart, Patrice; Tremblay, Bruno; Julien, Christian; Martin, Louis; Vachon, Carl

    2014-03-01

    A turn-key semi-automated test system was constructed to perform on-wafer testing of microbolometer arrays. The system allows for testing of several performance characteristics of ROIC-fabricated microbolometer arrays including NETD, SiTF, ROIC functionality, noise and matrix operability, both before and after microbolometer fabrication. The system accepts wafers up to 8 inches in diameter and performs automated wafer die mapping using a microscope camera. Once wafer mapping is completed, a custom-designed quick insertion 8-12 μm AR-coated Germanium viewport is placed and the chamber is pumped down to below 10-5 Torr, allowing for the evaluation of package-level focal plane array (FPA) performance. The probe card is electrically connected to an INO IRXCAM camera core, a versatile system that can be adapted to many types of ROICs using custom-built interface printed circuit boards (PCBs). We currently have the capability for testing 384x288, 35 μm pixel size and 160x120, 52 μm pixel size FPAs. For accurate NETD measurements, the system is designed to provide an F/1 view of two rail-mounted blackbodies seen through the Germanium window by the die under test. A master control computer automates the alignment of the probe card to the dies, the positioning of the blackbodies, FPA image frame acquisition using IRXCAM, as well as data analysis and storage. Radiometric measurement precision has been validated by packaging dies measured by the automated probing system and re-measuring the SiTF and Noise using INO's pre-existing benchtop system.

  11. Current Controller for Multi-level Front-end Converter and Its Digital Implementation Considerations on Three-level Flying Capacitor Topology

    Science.gov (United States)

    Tekwani, P. N.; Shah, M. T.

    2017-10-01

    This paper presents behaviour analysis and digital implementation of current error space phasor based hysteresis controller applied to three-phase three-level flying capacitor converter as front-end topology. The controller is self-adaptive in nature, and takes the converter from three-level to two-level mode of operation and vice versa, following various trajectories of sector change with the change in reference dc-link voltage demanded by the load. It keeps current error space phasor within the prescribed hexagonal boundary. During the contingencies, the proposed controller takes the converter in over modulation mode to meet the load demand, and once the need is satisfied, controller brings back the converter in normal operating range. Simulation results are presented to validate behaviour of controller to meet the said contingencies. Unity power factor is assured by proposed controller with low current harmonic distortion satisfying limits prescribed in IEEE 519-2014. Proposed controller is implemented using TMS320LF2407 16-bit fixed-point digital signal processor. Detailed analysis of numerical format to avoid overflow of sensed variables in processor, and per-unit model implementation in software are discussed and hardware results are presented at various stages of signal conditioning to validate the experimental setup. Control logic for the generation of reference currents is implemented in TMS320LF2407A using assembly language and experimental results are also presented for the same.

  12. Performance Assessment Monitoring Plan for the Hanford Site Low-Level Burial Grounds

    International Nuclear Information System (INIS)

    2006-01-01

    The U.S. Department of Energy Order 435.1, Radioactive Waste Management, requires a disposal authorization statement authorizing operation (or continued operation) for low-level waste disposal facilities. In fulfillment of these requirements, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area burial grounds and the 200 West Area burial grounds. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area low-level burial grounds be written and approved by the Richland Operations Office. As a result of a record of decision for the Hanford Site Solid Waste Program and acceptance of the Hanford Site Solid Waste Environmental Impact Statement, the use of the low-level burial ground (LLBG) as a disposal facility for low-level and mixed low-level wastes has been restricted to lined trenches and the Navy reactor-compartment trench only. Hence, as of July 2004, only the two lined trenches in burial ground 218-W-5 (trenches 31 and 34, see Appendix A) and the Navy reactor-compartment trench in burial ground 218 E 12B (trench 94) are allowed to receive waste. When the two lined trenches are filled, the LLBG will cease to operate except for reactor compartment disposal at trench 94. Remaining operational lifetime of the LLBG is dependent on waste volume disposal rates. Existing programs for air sampling and analyses and subsidence monitoring are currently adequate for performance assessment at the LLBG. The waste disposal authorization for the Hanford Site is based (in part) on the post-closure performance assessments for the LLBG. In order to maintain a useful link between operational monitoring (e.g., Resource Conservation and Recovery Act [RCRA], Comprehensive Environmental Response, Compensation, and Liability Act, and State Waste Discharge Permits), constituents, monitoring frequencies, and boundaries require

  13. Investigating influences on current community pharmacy practice at micro, meso, and macro levels.

    Science.gov (United States)

    Hermansyah, Andi; Sainsbury, Erica; Krass, Ines

    The nature of Australian community pharmacy is continually evolving, raising the need to explore the current situation in order to understand the potential impact of any changes. Although community pharmacy has the potential to play a greater role in health care, it is currently not meeting this potential. To investigate the nature of the contemporary practice of community pharmacy in Australia and examine the potential missed opportunities for role expansion in health care. In-depth semi-structured interviews with a wide-range of key stakeholders within and beyond community pharmacy circles were conducted. Interviews were audio-recorded, transcribed verbatim and analyzed for emerging themes. Twenty-seven key informants across Eastern half of Australia were interviewed between December 2014 and August 2015. Several key elements of the current situation representing the social, economic and policy context of community pharmacy have been identified. These elements operate interdependently, influence micro, meso and macro levels of community pharmacy operation and are changing in the current climate. Community pharmacy has untapped potential in primary health care, but it has been slow to change to meet opportunities available in the current situation. As the current situation is complex, interrelated and dynamic with often unintended and unpredictable consequences, this paper suggests that policy makers to consider the micro, meso and macro levels of community pharmacy operation when making significant policy changes. The framework proposed in this study can be a helpful tool to analyze the processes operating at these three levels and their influences on practice. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Low-level waste disposal performance assessments - Total source-term analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wilhite, E.L.

    1995-12-31

    Disposal of low-level radioactive waste at Department of Energy (DOE) facilities is regulated by DOE. DOE Order 5820.2A establishes policies, guidelines, and minimum requirements for managing radioactive waste. Requirements for disposal of low-level waste emplaced after September 1988 include providing reasonable assurance of meeting stated performance objectives by completing a radiological performance assessment. Recently, the Defense Nuclear Facilities Safety Board issued Recommendation 94-2, {open_quotes}Conformance with Safety Standards at Department of Energy Low-Level Nuclear Waste and Disposal Sites.{close_quotes} One of the elements of the recommendation is that low-level waste performance assessments do not include the entire source term because low-level waste emplaced prior to September 1988, as well as other DOE sources of radioactivity in the ground, are excluded. DOE has developed and issued guidance for preliminary assessments of the impact of including the total source term in performance assessments. This paper will present issues resulting from the inclusion of all DOE sources of radioactivity in performance assessments of low-level waste disposal facilities.

  15. Reducing Current Spread using Current Focusing in Cochlear Implant Users

    Science.gov (United States)

    Landsberger, David M.; Padilla, Monica; Srinivasan, Arthi G.

    2012-01-01

    Cochlear implant performance in difficult listening situations is limited by channel interactions. It is known that partial tripolar (PTP) stimulation reduces the spread of excitation (SOE). However, the greater the degree of current focusing, the greater the absolute current required to maintain a fixed loudness. As current increases, so does SOE. In experiment 1, the SOE for equally loud stimuli with different degrees of current focusing is measured via a forward-masking procedure. Results suggest that at a fixed loudness, some but not all patients have a reduced SOE with PTP stimulation. Therefore, it seems likely that a PTP speech processing strategy could improve spectral resolution for only those patients with a reduced SOE. In experiment 2, the ability to discriminate different levels of current focusing was measured. In experiment 3, patients subjectively scaled verbal descriptors of stimuli of various levels of current focusing. Both discrimination and scaling of verbal descriptors correlated well with SOE reduction, suggesting that either technique have the potential to be used clinically to quickly predict which patients would receive benefit from a current focusing strategy. PMID:22230370

  16. On the performance of 1-level LDPC lattices

    OpenAIRE

    Sadeghi, Mohammad-Reza; Sakzad, Amin

    2013-01-01

    The low-density parity-check (LDPC) lattices perform very well in high dimensions under generalized min-sum iterative decoding algorithm. In this work we focus on 1-level LDPC lattices. We show that these lattices are the same as lattices constructed based on Construction A and low-density lattice-code (LDLC) lattices. In spite of having slightly lower coding gain, 1-level regular LDPC lattices have remarkable performances. The lower complexity nature of the decoding algorithm for these type ...

  17. Neutral-point current modeling and control for Neutral-Point Clamped three-level converter drive with small DC-link capacitors

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Munk-Nielsen, Stig; Busquets-Monge, Sergio

    2011-01-01

    A Neutral-Point-Clamped (NPC) three-level inverter with small DC-link capacitors is presented in this paper. This inverter requires zero average neutral-point current for stable neutral-point potential. A simple carrier based modulation strategy is proposed for achieving zero average neutral...... drive with only 14 μF DC-link capacitors. A fast and stable performance of the neutral-point voltage controller is achieved and verified by experiments....

  18. The Association of Leisure Activities in Middle Adulthood with Cognitive Performance in Old Age: The Moderating Role of Educational Level.

    Science.gov (United States)

    Ihle, Andreas; Oris, Michel; Fagot, Delphine; Baeriswyl, Marie; Guichard, Eduardo; Kliegel, Matthias

    2015-01-01

    One of the fundamental challenges for gerontological research is how to maintain and promote intact cognitive functioning in old age. Previous research revealed that high educational level, good health status, and an active lifestyle during adulthood seem to be protective against cognitive impairment in old age. However, up to now, a detailed examination of the interaction of these relations based on a broader variety of activities and considering past and current activities is missing. The present study set out to extend the literature by investigating in more detail the interactions of educational level and health status with a broad variety of past and current leisure activities in their association with cognitive functioning in a large sample of older adults with a wide age range. A total of 2,812 older adults (aged 65-101 years) served as the sample for the present study. A test on verbal abilities and one on processing speed were applied. In addition, individuals were retrospectively interviewed regarding their educational level, current general health status, and 18 leisure activities (in terms of currently performed activities and those that had been carried out at the age of 45 years). Regressions indicated that engaging in more current activities and in more activities at the age of 45 years (both analyzed as an overall activity measure) was related to better cognitive performance in old age (r values up to 0.39, p values <0.001). These associations were more pronounced in individuals with a low (compared to a high) educational level. Present results suggest that an active lifestyle during middle adulthood may be related to better cognitive functioning in old age, particularly in individuals with a low educational level. These findings are discussed with respect to models of cognitive aging. © 2015 S. Karger AG, Basel.

  19. Current Account Balance and Export Performances: Evidence Based on New EU Countries

    Directory of Open Access Journals (Sweden)

    Bogdan Željko

    2017-11-01

    Full Text Available In this paper, we investigate whether the differences in the current account balance and export performances for a new EU countries are a result of exchange rate policies. The analysis shows that countries with a flexible exchange rate have better export performances and the current account balance in the pre-crisis period. The obtained results show that movements in the current account balance are mainly driven by domestic variables. In the countries with a flexible exchange rate, real and nominal depreciation affects export positively although the magnitude of these effects is tiny and limited to the crisis period. These results point to a higher significance of non-price competitiveness on export which should be a future research topic.

  20. Current and future levels of mercury atmospheric pollution on global scale

    NARCIS (Netherlands)

    Pacyna, Jozef M.; Travnikov, Oleg; De Simone, Francesco; Hedgecock, Ian M.; Sundseth, Kyrre; Pacyna, Elisabeth G.; Steenhuisen, Frits; Pirrone, Nicola; Munthe, John; Kindbom, Karin

    2016-01-01

    An assessment of current and future emissions, air concentrations and atmospheric deposition of mercury world-wide are presented on the basis of results obtained during the performance of the EU GMOS (Global Mercury Observation System) project. Emission estimates for mercury were prepared with the

  1. Total system performance predictions (TSPA-1995) for the potential high-level waste repository at Yucca Mountain

    International Nuclear Information System (INIS)

    Sevougian, S.D.; Andrews, R.W.; McNeish, J.A.

    1996-01-01

    The management and operating contractor for the potential high-level nuclear waste repository at Yucca Mountain, Nevada, has been recently completed a new performance assessment of the ability of the repository to isolate and contain nuclear waste for long time periods (up to 1,000,000 years). Sensitivity analyses determine the most important physical parameters and processes, using the most current information and models

  2. Performance demonstration tests for eddy current inspection of steam generator tubing

    International Nuclear Information System (INIS)

    Kurtz, R.J.; Heasler, P.G.; Anderson, C.M.

    1996-05-01

    This report describes the methodology and results for development of performance demonstration tests for eddy current (ET) inspection of steam generator tubes. Statistical test design principles were used to develop the performance demonstration tests. Thresholds on ET system inspection performance were selected to ensure that field inspection systems would have a high probability of detecting and and correctly sizing tube degradation. The technical basis for the ET system performance thresholds is presented in detail. Statistical test design calculations for probability of detection and flaw sizing tests are described. A recommended performance demonstration test based on the design calculations is presented. A computer program for grading the probability of detection portion of the performance demonstration test is given

  3. Performance demonstration tests for eddy current inspection of steam generator tubing

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, R.J.; Heasler, P.G.; Anderson, C.M.

    1996-05-01

    This report describes the methodology and results for development of performance demonstration tests for eddy current (ET) inspection of steam generator tubes. Statistical test design principles were used to develop the performance demonstration tests. Thresholds on ET system inspection performance were selected to ensure that field inspection systems would have a high probability of detecting and and correctly sizing tube degradation. The technical basis for the ET system performance thresholds is presented in detail. Statistical test design calculations for probability of detection and flaw sizing tests are described. A recommended performance demonstration test based on the design calculations is presented. A computer program for grading the probability of detection portion of the performance demonstration test is given.

  4. Current Trends in High-Level Synthesis of Asynchronous Circuits

    DEFF Research Database (Denmark)

    Sparsø, Jens

    2009-01-01

    This paper is a survey paper presenting what the author sees as two major and promising trends in the current research in CAD-tools and design-methods for asynchronous circuits. One branch of research builds on top of existing asynchronous CAD-tools that perform syntax directed translation, e...... a conventional synchronous circuit as the starting point, and then adds some form of handshake-based flow-control. One approach keeps the global clock and implements discrete-time asynchronous operation. Another approach substitutes the clocked registers by asynchronous handshake-registers, thus creating truly...

  5. Fundamental Adriatic seiche recorded by current meters

    Directory of Open Access Journals (Sweden)

    N. Leder

    2004-04-01

    Full Text Available Currents recorded at two stations positioned at the Adriatic shelf break between 17 February and 6 March 1989 were considered. They provided the first evidence of current variability related to the Adriatic-wide seiches. Current spectra were dominated by a peak at 21.1h – a well-known period of the fundamental Adriatic mode. Amplitudes of oscillations were considerable, occasionally greater than 30cm/s. Both along- and cross-basin currents were recorded, thus signalling the importance of rotational effects. Comparison of the current data with the sea-level measurements performed simultaneously along the east Adriatic coast showed that the 21-h currents flowing in the Adriatic preceded sea levels by a quarter of a cycle, as would be expected from a simple model of bay seiches. Sea-level amplitudes reached 40cm in the North Adriatic, thus marking the event as one of the strongest on record. Seiching was triggered by a suddenly changing sirocco wind, as is usually the case in the Adriatic. The most important features of the seiche event were reproduced with a two-dimensional hydrodynamic model of the Adriatic Sea, forced by the sea-level residuals measured at Otranto and the air pressure and wind data recorded at Lastovo. The model showed that the seiche-related currents were relatively strong in the area where the current measurements were performed and further north – between Zadar and Ancona. Key words. Oceanography: general (continental shelf processes – Oceanography: physical (sea-level variations, currents

  6. [A school-level longitudinal study of clinical performance examination scores].

    Science.gov (United States)

    Park, Jang Hee

    2015-06-01

    This school-level longitudinal study examined 7 years of clinical performance data to determine differences (effects) in students and annual changes within a school and between schools; examine how much their predictors (characteristics) influenced the variation in student performance; and calculate estimates of the schools' initial status and growth. A school-level longitudinal model was tested: level 1 (between students), level 2 (annual change within a school), and level 3 (between schools). The study sample comprised students who belonged to the CPX Consortium (n=5,283 for 2005~2008 and n=4,337 for 2009~2011). Despite a difference between evaluation domains, the performance outcomes were related to individual large-effect differences and small-effect school-level differences. Physical examination, clinical courtesy, and patient education were strongly influenced by the school effect, whereas patient-physician interaction was not affected much. Student scores are influenced by the school effect (differences), and the predictors explain the variation in differences, depending on the evaluation domain.

  7. Impact of Educational Level on Performance on Auditory Processing Tests.

    Science.gov (United States)

    Murphy, Cristina F B; Rabelo, Camila M; Silagi, Marcela L; Mansur, Letícia L; Schochat, Eliane

    2016-01-01

    Research has demonstrated that a higher level of education is associated with better performance on cognitive tests among middle-aged and elderly people. However, the effects of education on auditory processing skills have not yet been evaluated. Previous demonstrations of sensory-cognitive interactions in the aging process indicate the potential importance of this topic. Therefore, the primary purpose of this study was to investigate the performance of middle-aged and elderly people with different levels of formal education on auditory processing tests. A total of 177 adults with no evidence of cognitive, psychological or neurological conditions took part in the research. The participants completed a series of auditory assessments, including dichotic digit, frequency pattern and speech-in-noise tests. A working memory test was also performed to investigate the extent to which auditory processing and cognitive performance were associated. The results demonstrated positive but weak correlations between years of schooling and performance on all of the tests applied. The factor "years of schooling" was also one of the best predictors of frequency pattern and speech-in-noise test performance. Additionally, performance on the working memory, frequency pattern and dichotic digit tests was also correlated, suggesting that the influence of educational level on auditory processing performance might be associated with the cognitive demand of the auditory processing tests rather than auditory sensory aspects itself. Longitudinal research is required to investigate the causal relationship between educational level and auditory processing skills.

  8. The effects of high frequency current ripple on electric vehicle battery performance

    International Nuclear Information System (INIS)

    Uddin, Kotub; Moore, Andrew D.; Barai, Anup; Marco, James

    2016-01-01

    Highlights: • Experimental study into the impact of current ripple on li-ion battery degradation. • 15 cells exercised with 1200 cycles coupled AC–DC signals, at 5 frequencies. • Results highlight a greater spread of degradation for cells exposed to AC excitation. • Implications for BMS control, thermal management and system integration. - Abstract: The power electronic subsystems within electric vehicle (EV) powertrains are required to manage both the energy flows within the vehicle and the delivery of torque by the electrical machine. Such systems are known to generate undesired electrical noise on the high voltage bus. High frequency current oscillations, or ripple, if unhindered will enter the vehicle’s battery system. Real-world measurements of the current on the high voltage bus of a series hybrid electric vehicle (HEV) show that significant current perturbations ranging from 10 Hz to in excess of 10 kHz are present. Little is reported within the academic literature about the potential impact on battery system performance and the rate of degradation associated with exposing the battery to coupled direct current (DC) and alternating currents (AC). This paper documents an experimental investigation that studies the long-term impact of current ripple on battery performance degradation. Initial results highlight that both capacity fade and impedance rise progressively increase as the frequency of the superimposed AC current increases. A further conclusion is that the spread of degradation for cells cycled with a coupled AC–DC signal is considerably more than for cells exercised with a traditional DC waveform. The underlying causality for this degradation is not yet understood. However, this has important implications for the battery management system (BMS). Increased variations in cell capacity and impedance will cause differential current flows and heat generation within the battery pack that if not properly managed will further reduce battery life

  9. Performance assessment handbook for low-level radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    Seitz, R.R.; Garcia, R.S.; Kostelnik, K.M.; Starmer, R.J.

    1992-02-01

    Performance assessments of proposed low-level radioactive waste disposal facilities must be conducted to support licensing. This handbook provides a reference document that can be used as a resource by management and staff responsible for performance assessments. Brief discussions describe the performance assessment process and emphasize selected critical aspects of the process. References are also provided for additional information on many aspects of the performance assessment process. The user's manual for the National Low-Level Waste Management Program's Performance Assessment Center (PAC) on the Idaho National Engineering Laboratory Cray computer is included as Appendix A. The PAC provides users an opportunity to experiment with a number of performance assessment computer codes on a Cray computer. Appendix B describes input data required for 22 performance assessment codes

  10. Tri-State Current Source Inverter With Improved Dynamic Performance

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, Poh Chiang; Wong, Chow Pang

    2008-01-01

    Traditional dc-ac current source inverter (CSI) has a right-half-plane (RHP) zero in its control-to-output transfer function. This RHP zero causes the inverter output to fall before rising when a step increase in command reference is required (commonly known as non-minimum-phase effect). To achieve...... a better dynamic response, this paper proposes the design of a tri-state CSI using only an additional semiconductor switch for introducing unique freewheeling states to the traditional six active and three null states of a CSI. With the freewheeling states inserted appropriately within the inverter state...... sequence, the inductive boosting and discharging intervals can be decoupled, allowing the RHP zero to be eliminated with only minor circuit modifications (high level control schemes like predictive and multiloop voltage/current control remain unchanged). The designed inverter can be controlled using...

  11. The Relationship of Learning and Performance Diagnosis at Different System Levels.

    Science.gov (United States)

    Lubega, Khalid

    2003-01-01

    Examines learning and performance diagnosis, separately and in relation to each other, as they function in organization systems; explains the relationship between learning and performance diagnosis at the individual, process, and organizational levels using a three-level performance model; and discusses types of learning, including nonlearning,…

  12. Modelling Client Satisfaction Levels: The Impact of Contractor Performance

    Directory of Open Access Journals (Sweden)

    Robby Soetanto

    2012-11-01

    Full Text Available The performance of contractors is known to be a key determinant of client satisfaction.Here, using factor analysis, clients’ satisfaction is defined in several dimensions. Based onclients’ assessment of contractor performance, a number of satisfaction models developedusing the multiple regression (MR technique are presented. The models identify arange of variables encompassing contractor performance, project performance and respondent(i.e. client attributes as useful predictors of satisfaction levels. Contractor performanceattributes were found to be of utmost importance indicating that clientsatisfaction levels are mainly dependent on the performance of the contractor. Furthermore,findings suggest that subjectivity is to some extent prevalent in clients’ performanceassessment. The models demonstrate accurate and reliable predictive power as confirmedby validation tests. Contractors could use the models to help improve their performanceleading to more satisfied clients. This would also promote the development ofharmonious working relationships within the construction project coalition.

  13. Low-level radioactive waste performance assessments: Source term modeling

    International Nuclear Information System (INIS)

    Icenhour, A.S.; Godbee, H.W.; Miller, L.F.

    1995-01-01

    Low-level radioactive wastes (LLW) generated by government and commercial operations need to be isolated from the environment for at least 300 to 500 yr. Most existing sites for the storage or disposal of LLW employ the shallow-land burial approach. However, the U.S. Department of Energy currently emphasizes the use of engineered systems (e.g., packaging, concrete and metal barriers, and water collection systems). Future commercial LLW disposal sites may include such systems to mitigate radionuclide transport through the biosphere. Performance assessments must be conducted for LUW disposal facilities. These studies include comprehensive evaluations of radionuclide migration from the waste package, through the vadose zone, and within the water table. Atmospheric transport mechanisms are also studied. Figure I illustrates the performance assessment process. Estimates of the release of radionuclides from the waste packages (i.e., source terms) are used for subsequent hydrogeologic calculations required by a performance assessment. Computer models are typically used to describe the complex interactions of water with LLW and to determine the transport of radionuclides. Several commonly used computer programs for evaluating source terms include GWSCREEN, BLT (Breach-Leach-Transport), DUST (Disposal Unit Source Term), BARRIER (Ref. 5), as well as SOURCE1 and SOURCE2 (which are used in this study). The SOURCE1 and SOURCE2 codes were prepared by Rogers and Associates Engineering Corporation for the Oak Ridge National Laboratory (ORNL). SOURCE1 is designed for tumulus-type facilities, and SOURCE2 is tailored for silo, well-in-silo, and trench-type disposal facilities. This paper focuses on the source term for ORNL disposal facilities, and it describes improved computational methods for determining radionuclide transport from waste packages

  14. An evaluation of current high-performance networks

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Christian; Bonachea, Dan; Cote, Yannick; Duell, Jason; Hargrove, Paul; Husbands, Parry; Iancu, Costin; Welcome, Michael; Yelick, Katherine

    2003-01-25

    High-end supercomputers are increasingly built out of commodity components, and lack tight integration between the processor and network. This often results in inefficiencies in the communication subsystem, such as high software overheads and/or message latencies. In this paper we use a set of microbenchmarks to quantify the cost of this commoditization, measuring software overhead, latency, and bandwidth on five contemporary supercomputing networks. We compare the performance of the ubiquitous MPI layer to that of lower-level communication layers, and quantify the advantages of the latter for small message performance. We also provide data on the potential for various communication-related optimizations, such as overlapping communication with computation or other communication. Finally, we determine the minimum size needed for a message to be considered 'large' (i.e., bandwidth-bound) on these platforms, and provide historical data on the software overheads of a number of supercomputers over the past decade.

  15. 76 FR 52548 - National Veterinary Accreditation Program; Currently Accredited Veterinarians Performing...

    Science.gov (United States)

    2011-08-23

    .... APHIS-2006-0093] RIN 0579-AC04 National Veterinary Accreditation Program; Currently Accredited... accredited in the National Veterinary Accreditation Program (NVAP) may continue to perform accredited duties..., 2011. FOR FURTHER INFORMATION CONTACT: Dr. Todd Behre, National Veterinary Accreditation Program, VS...

  16. Current and future levels of mercury atmospheric pollution on a global scale

    NARCIS (Netherlands)

    Pacyna, J. M.; Travnikov, O.; De Simone, F.; Hedgecock, I. M.; Sundseth, K.; Pacyna, E. G.; Steenhuisen, F.; Pirrone, N.; Munthe, J.; Kindbom, K.

    2016-01-01

    An assessment of current and future emissions, air concentrations, and atmospheric deposition of mercury worldwide is presented on the basis of results obtained during the performance of the EU GMOS (Global Mercury Observation System) project. Emission estimates for mercury were prepared with the

  17. The ATLAS High Level Trigger Infrastructure, Performance and Future Developments

    CERN Document Server

    The ATLAS collaboration

    2009-01-01

    The ATLAS High Level Trigger (HLT) is a distributed real-time software system that performs the final online selection of events produced during proton-proton collisions at the Large Hadron Collider (LHC). It is designed as a two-stage event filter running on a farm of commodity PC hardware. Currently the system consists of about 850 multi-core processing nodes that will be extended incrementally following the increasing luminosity of the LHC to about 2000 nodes depending on the evolution of the processor technology. Due to the complexity and similarity of the algorithms a large fraction of the software is shared between the online and offline event reconstruction. The HLT Infrastructure serves as the interface between the two domains and provides common services for the trigger algorithms. The consequences of this design choice will be discussed and experiences from the operation of the ATLAS HLT during cosmic ray data taking and first beam in 2008 will be presented. Since the event processing time at the HL...

  18. Impacts of government subsidies on pricing and performance level choice in Energy Performance Contracting: A two-step optimal decision model

    International Nuclear Information System (INIS)

    Lu, Zhijian; Shao, Shuai

    2016-01-01

    Highlights: • An ESCO optimal decision model considering governmental subsidies is proposed. • Optimal price and performance level are deduced via a two-stage model. • Demand, profit, and performance level increase with increasing subsidies. • ESCO’s market strategy should firstly focus on high energy consumption industries. • Governmental subsidies standard in different industries should be differentiated. - Abstract: Government subsidies generally play a crucial role in pricing and the choice of performance levels in Energy Performance Contracting (EPC). However, the existing studies pay little attention to how the Energy Service Company (ESCO) prices and chooses performance levels for EPC with government subsidies. To fill such a gap, we propose a joint optimal decision model of pricing and performance level in EPC considering government subsidies. The optimization of the model is achieved via a two-stage process. At the first stage, given a performance level, ESCOs choose the best price; and at the second stage, ESCOs choose the optimal performance level for the optimal price. Furthermore, we carry out a numerical analysis to illuminate such an optimal decision mechanism. The results show that both price sensitivity and performance level sensitivity have significant effects on the choice of performance levels with government subsidies. Government subsidies can induce higher performance levels of EPC, the demand for EPC, and the profit of ESCO. We suggest that ESCO’s market strategy should firstly focus on high energy consumption industries with government subsidies and that government subsidies standard adopted in different industries should be differentiated according to the market characteristics and energy efficiency levels of various industries.

  19. How to harness the performance potential of current multi-core processors

    International Nuclear Information System (INIS)

    Jarp, Sverre; Lazzaro, Alfio; Leduc, Julien; Nowak, Andrzej

    2011-01-01

    Leakage currents have put a stop to the semiconductor industry's ability to increase processor frequency in order to enhance the performance of new microprocessors. Instead, we observe a slew of changes inside the micro-architecture with an aim of enhancing the performance. Several of these changes, however, do not translate into automatic speed improvements for the software. This paper discusses the increased complexity of modern microprocessors by separating out into dimensions each feature that impacts performance and mentions briefly ways of improving software, in particular that of the High Energy Physics community, to take full advantage.

  20. Investigation of students’ intermediate conceptual understanding levels: the case of direct current electricity concepts

    International Nuclear Information System (INIS)

    Aktan, D Cobanoglu

    2013-01-01

    Conceptual understanding is one of the main topics in science and physics education research. In the majority of conceptual understanding studies, students’ understanding levels were categorized dichotomously, either as alternative or scientific understanding. Although they are invaluable in many ways, namely developing new instructional materials and assessment instruments, students’ alternative understandings alone are not sufficient to describe students’ conceptual understanding in detail. This paper introduces an example of a study in which a method was developed to assess and describe students’ conceptual understanding beyond alternative and scientific understanding levels. In this study, six undergraduate students’ conceptual understanding levels of direct current electricity concepts were assessed and described in detail by using their answers to qualitative problems. In order to do this, conceptual understanding indicators are described based on science and mathematics education literature. The students’ understanding levels were analysed by assertion analysis based on the conceptual understanding indicators. The results indicated that the participants demonstrated three intermediate understanding levels in addition to alternative and scientific understanding. This paper presents the method and its application to direct current electricity concepts. (paper)

  1. Level of training and experience in physicians performing interhospital transfers of adult patients in the internal medicine department

    DEFF Research Database (Denmark)

    Hallas, P; Folkestad, L; Brabrand, M

    2009-01-01

    AIM: To establish the level of training doctors who participate in interhospital transfers in Denmark. METHODS: A questionnaire was sent to every hospital department in Denmark with acute internal medicine admissions. RESULTS: Eighty-nine internal medicine departments were contacted and 84...... responded (response rate 94.4%). Of the 84 hospitals, 75 (89.3%) indicated that they perform interhospital transfers. Most transfers were performed by interns (61.3%) or senior house officers (10.7%) with only a few months' experience in their current speciality. Training in interhospital transfer...

  2. 10 CFR 433.5 - Performance level determination.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Performance level determination. 433.5 Section 433.5 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR THE DESIGN AND...) Each Federal agency shall consider laboratory fume hoods and kitchen ventilation systems as part of the...

  3. Empirically Examining the Performance of Approaches to Multi-Level Matching to Study the Effect of School-Level Interventions

    Science.gov (United States)

    Hallberg, Kelly; Cook, Thomas D.; Figlio, David

    2013-01-01

    The goal of this paper is to provide guidance for applied education researchers in using multi-level data to study the effects of interventions implemented at the school level. Two primary approaches are currently employed in observational studies of the effect of school-level interventions. One approach employs intact school matching: matching…

  4. The role of incline, performance level, and gender on the gross mechanical efficiency of roller ski skating

    Science.gov (United States)

    Sandbakk, Øyvind; Hegge, Ann Magdalen; Ettema, Gertjan

    2013-01-01

    The ability to efficiently utilize metabolic energy to produce work is a key factor for endurance performance. The present study investigated the effects of incline, performance level, and gender on the gross mechanical efficiency during roller ski skating. Thirty-one male and nineteen female elite cross-country skiers performed a 5-min submaximal session at approximately 75% of VO2peak on a 5% inclined treadmill using the G3 skating technique. Thereafter, a 5-min session on a 12% incline using the G2 skating technique was performed at a similar work rate. Gross efficiency was calculated as the external work rate against rolling friction and gravity divided by the metabolic rate using gas exchange. Performance level was determined by the amount of skating FIS points [the Federation of International Skiing (FIS) approved scoring system for ski racing] where fewer points indicate a higher performance level. Strong significant correlations between work rate and metabolic rate within both inclines and gender were revealed (r = −0.89 to 0.98 and P < 0.05 in all cases). Gross efficiency was higher at the steeper incline, both for men (17.1 ± 0.4 vs. 15.8 ± 0.5%, P < 0.05) and women (16.9 ± 0.5 vs. 15.7 ± 0.4%, P < 0.05), but without any gender differences being apparent. Significant correlations between gross efficiency and performance level were found for both inclines and genders (r = −0.65 to 0.81 and P < 0.05 in all cases). The current study demonstrated that cross-country skiers of both genders used less metabolic energy to perform the same amount of work at steeper inclines, and that the better ranked elite male and female skiers skied more efficiently. PMID:24155722

  5. Direct-Current Forced Interruption and Breaking Performance of Spiral-Type Contacts in Aero Applications

    Directory of Open Access Journals (Sweden)

    Wenlei Huo

    2017-05-01

    Full Text Available This paper analyses the transient characteristics and breaking performance of direct-current (DC forced-interruption vacuum interrupters in 270 V power-supply systems. Three stages are identified in forced interruption: the DC-arcing stage, current-commutation stage, and voltage-recovery stage. During the current-commutation stage, the reverse peak-current coefficient k, which is a key design factor, is used to calculate the rate of current at zero-crossing (di/dt. MATLAB/Simulink simulation models are established to obtain the transient characteristics influenced by the forced-commutation branch parameters and the coefficient k. To study the breaking performance of spiral-type contacts, experiments are conducted for different contact materials and arcing times for currents less than 3.5 kA. During the DC-arcing stage, a locally intensive burning arc is observed in the CuW80 contact; however, it is not observed in the CuCr50 contact. On examining the re-ignition interruption results of the CuW80 contact, the intensive burning arc is found to be positioned within a possible re-ignition region. When the arcing time is longer than 1 ms, the intensive burning arc occurs and affects the breaking performance of the spiral-type contacts. If the DC-arcing stage is prolonged, the total arcing energy increases, which leads to a lower breaking capacity.

  6. Elimination of zero sequence circulating current between parallel operating three-level inverters

    DEFF Research Database (Denmark)

    Li, Kai; Wang, Xiaodong; Dong, Zhenhua

    2016-01-01

    In order to suppress the zero sequence circulating currents (ZSCCs) between parallel operating three level voltage source inverters with common AC and DC buses, a common mode voltage reduction PWM (CMVR-PWM) technique and neural point potentials (NPPs) control based method is proposed in this paper...

  7. Impact of high-performance work systems on individual- and branch-level performance: test of a multilevel model of intermediate linkages.

    Science.gov (United States)

    Aryee, Samuel; Walumbwa, Fred O; Seidu, Emmanuel Y M; Otaye, Lilian E

    2012-03-01

    We proposed and tested a multilevel model, underpinned by empowerment theory, that examines the processes linking high-performance work systems (HPWS) and performance outcomes at the individual and organizational levels of analyses. Data were obtained from 37 branches of 2 banking institutions in Ghana. Results of hierarchical regression analysis revealed that branch-level HPWS relates to empowerment climate. Additionally, results of hierarchical linear modeling that examined the hypothesized cross-level relationships revealed 3 salient findings. First, experienced HPWS and empowerment climate partially mediate the influence of branch-level HPWS on psychological empowerment. Second, psychological empowerment partially mediates the influence of empowerment climate and experienced HPWS on service performance. Third, service orientation moderates the psychological empowerment-service performance relationship such that the relationship is stronger for those high rather than low in service orientation. Last, ordinary least squares regression results revealed that branch-level HPWS influences branch-level market performance through cross-level and individual-level influences on service performance that emerges at the branch level as aggregated service performance.

  8. Model and performance of current sensor observers for a doubly fed induction generator

    DEFF Research Database (Denmark)

    Li, Hui; Yang, Chao; Hu, Yaogang

    2014-01-01

    . A stator and rotor current observer model, which is based on the state-space models of doubly fed induction generators, is then derived by using the stator and rotor voltage signals as inputs. To demonstrate the effectiveness of the proposed current observer, its dynamic performance is simulated using...

  9. LENDING IN FOREIGN CURRENCY AND CURRENT CHALLENGES AT EUROPEAN LEVEL

    Directory of Open Access Journals (Sweden)

    ȘARGU Alina Camelia

    2012-12-01

    Full Text Available In recent years, most countries in Central and Eastern Europe, Member States of the EU, that we selected for the analysis (Bulgaria, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania have recorded a significant expansion of lending in foreign currency, which was one of the major factors of the accelerated growth of loans to economy. Such developments have led to an increase of indebtedness in foreign currency of the non-financial private sector, especially of the households and of the accumulation of major macroeconomics and financial imbalances. The issue of lending in foreign currency, the determinants of increasing the share of loans in foreign currency and the risks generated at the level of financial stability are the subject of numerous studies, including: Basso, Calvo-Gonzales and Jurgilas (2007; Rosenberg and Tirpak (2008; Csajbók-Andras et al. (2010; Zettelmeyer, Nagy and Jeffrey (2010. Another significant issue addressed in the specialized literature regarding foreign currency loans refers to the role of monetary policy in limiting growth of these loans. Thus, in addition to those noted studies we remark other studies, such as: Kiss et al. (2006; Sirtaine and Skamnelos (2007; Hilbers et al. (2006; Brzoza-Brzezina et al. (2010. Our paper complements the specialized literature on the approached subject, in particular, by highlighting and discussing current issues of high interest for policymakers, both at national and European level regarding lending in foreign currency. The extremely negative implications of lending in foreign currency on financial stability in most countries under review, outlined clearly in the context of the current crisis, determined the focus of the policymakers concern, both at European and national level, regarding the issue of foreign currency loans, which became one of the most discussed issues on the agenda of the monetary-financial authorities. The aim of our research is to

  10. Immigration and Firm Performance: a city-level approach

    Directory of Open Access Journals (Sweden)

    Mercedes Teruel Carrizosa

    2009-10-01

    Full Text Available This article analyses the effect of immigration flows on the growthand efficiency of manufacturing firms in Spanish cities. While most studies werefocusing on the effect immigrants have on labour markets at an aggregate level,here, we argue that the impact of immigration on firm performance should not onlybe considered in terms of the labour market, but also in terms of how city’s amenitiescan affect the performance of firms. Implementing a panel data methodology,we show that the immigrants’ increasing pressure has a positive effect on labourproductivity and wages and a negative effect on the job evolution of these manufacturingfirms. In addition, both small and new firms are more sensitive to thepressures of immigrant inflow, while foreign market oriented firms report higherproductivity levels and a less marked impact of immigration than their counterparts.We also present a set of instruments to control for endogeneity. It allows us toconfirm the effect of local immigration flows on the performance of manufacturingfirms.

  11. Judging in Rhythmic Gymnastics at Different Levels of Performance.

    Science.gov (United States)

    Leandro, Catarina; Ávila-Carvalho, Lurdes; Sierra-Palmeiro, Elena; Bobo-Arce, Marta

    2017-12-01

    This study aimed to analyse the quality of difficulty judging in rhythmic gymnastics, at different levels of performance. The sample consisted of 1152 difficulty scores concerning 288 individual routines, performed in the World Championships in 2013. The data were analysed using the mean absolute judge deviation from the final difficulty score, a Cronbach's alpha coefficient and intra-class correlations, for consistency and reliability assessment. For validity assessment, mean deviations of judges' difficulty scores, the Kendall's coefficient of concordance W and ANOVA eta-squared values were calculated. Overall, the results in terms of consistency (Cronbach's alpha mostly above 0.90) and reliability (intra-class correlations for single and average measures above 0.70 and 0.90, respectively) were satisfactory, in the first and third parts of the ranking on all apparatus. The medium level gymnasts, those in the second part of the ranking, had inferior reliability indices and highest score dispersion. In this part, the minimum of corrected item-total correlation of individual judges was 0.55, with most values well below, and the matrix for between-judge correlations identified remarkable inferior correlations. These findings suggest that the quality of difficulty judging in rhythmic gymnastics may be compromised at certain levels of performance. In future, special attention should be paid to the judging analysis of the medium level gymnasts, as well as the Code of Points applicability at this level.

  12. On the increase of predictive performance with high-level data fusion

    International Nuclear Information System (INIS)

    Doeswijk, T.G.; Smilde, A.K.; Hageman, J.A.; Westerhuis, J.A.; Eeuwijk, F.A. van

    2011-01-01

    The combination of the different data sources for classification purposes, also called data fusion, can be done at different levels: low-level, i.e. concatenating data matrices, medium-level, i.e. concatenating data matrices after feature selection and high-level, i.e. combining model outputs. In this paper the predictive performance of high-level data fusion is investigated. Partial least squares is used on each of the data sets and dummy variables representing the classes are used as response variables. Based on the estimated responses y-hat j for data set j and class k, a Gaussian distribution p(g k |y-hat j ) is fitted. A simulation study is performed that shows the theoretical performance of high-level data fusion for two classes and two data sets. Within group correlations of the predicted responses of the two models and differences between the predictive ability of each of the separate models and the fused models are studied. Results show that the error rate is always less than or equal to the best performing subset and can theoretically approach zero. Negative within group correlations always improve the predictive performance. However, if the data sets have a joint basis, as with metabolomics data, this is not likely to happen. For equally performing individual classifiers the best results are expected for small within group correlations. Fusion of a non-predictive classifier with a classifier that exhibits discriminative ability lead to increased predictive performance if the within group correlations are strong. An example with real life data shows the applicability of the simulation results.

  13. Electrooptic Methods for Measurement of Small DC Currents at High Voltage Level

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Beatty, Neville; Skilbreid, Asbjørn Ottar

    1989-01-01

    collectors are connected via resistors RA and RB to the protective side of the voltage to be measured and the emitters to the negative side. The currents flowing in to the bases of the transistors are independently controlled by the light levels following on the two photodiodes PDA, PDB....

  14. 75 FR 59605 - National Veterinary Accreditation Program; Currently Accredited Veterinarians Performing...

    Science.gov (United States)

    2010-09-28

    .... APHIS-2006-0093] RIN 0579-AC04 National Veterinary Accreditation Program; Currently Accredited... Veterinary Accreditation Program (NVAP) may continue to perform accredited duties and to elect to continue to..., National Veterinary Accreditation Program, VS, APHIS, 4700 River Road Unit 200, Riverdale, MD 20737; (301...

  15. Low-level radioactive waste management at the Nevada Test Site - Current status

    International Nuclear Information System (INIS)

    Becker, B.D.; Crowe, B.M.; Gertz, C.P.; Clayton, W.A.

    1999-01-01

    The performance objectives of the Department of Energy's Low-Level Radioactive Waste (LLW) disposal facilities located at the Nevada Test Site transcend those of any other radioactive waste disposal site in the US. Situated at the southern end of the Great Basin, 800 feet above the water table, the Area 5 Radioactive Waste Management Site (RWMS) has utilized a combination of engineered shallow land disposal cells and deep augured shafts to dispose a variety of waste streams. These include high volume low-activity wastes, classified materials, and high-specific-activity special case wastes. Twenty miles north of Area 5 is the Area 3 RWMS. Here bulk LLW disposal takes place in subsidence craters formed from underground testing of nuclear weapons. Earliest records indicate that documented LLW disposal activities have occurred at the Area 5 and Area 3 RWMS's since 1961 and 1968, respectively. However, these activities have only been managed under a formal program since 1978. This paper describes the technical attributes of the facilities, present and future capacities and capabilities, and provides a description of the process from waste approval to final disposition. The paper also summarizes the current status of the waste disposal operations

  16. Forget the Desk Job: Current Roles and Responsibilities in Entry-Level Reference Job Advertisements

    Science.gov (United States)

    Detmering, Robert; Sproles, Claudene

    2012-01-01

    This study examines the evolving roles and responsibilities of entry-level academic reference positions, as stated in recent job advertisements posted on the American Library Association's JobLIST Web site and other sources. Findings from a content analysis of these advertisements indicate that current entry-level reference positions in academic…

  17. Elicitation and use of expert judgment in performance assessment for high-level radioactive waste repositories

    International Nuclear Information System (INIS)

    Bonano, E.J.; Hora, S.C.; Keeney, R.L.; von Winterfeldt, D.

    1990-05-01

    This report presents the concept of formalizing the elicitation and use of expert judgment in the performance assessment of high-level radioactive waste (HLW) repositories in deep geologic formations. The report begins with a discussion of characteristics (advantages and disadvantages) of formalizing expert judgment examples of previous uses of expert judgment in radioactive waste programs, criteria that can assist in deciding when to formalize expert judgment, and the relationship of formal use of expert judgment to data collection and modeling. The current state of the art with respect to the elicitation, use, and communication of formal expert judgment is presented. The report concludes with a discussion on potential applications of formal expert judgment in performance assessment of HLW repositories. 93 refs

  18. Performance assessment for low-level radioactive waste disposal

    International Nuclear Information System (INIS)

    Cook, J.R.; Hsu, R.H.; Wilhite, E.L.; Yu, A.D.

    1996-01-01

    In October 1994 the Savannah River Site became the first US DOE complex to use concrete vaults to dispose of low-level radioactive solid waste and better prevent soil and groundwater contamination. This article describes the design and gives a performance assessment of the vaults. Topics include the following: Performance objectives; scope; the performance assessment process-assemble a multidisciplinary working group; collect available data; define credible pathways/scenarios; develop conceptual models; conduct screening and detailed model calculations; assess sensitivity/uncertainty; integrate and interpret results; report. 9 figs., 3 tabs

  19. Match activities of elite women soccer players at different performance levels

    DEFF Research Database (Denmark)

    Mohr, Magni; Krustrup, Peter; Andersson, Helena

    2008-01-01

    , (2) fatigue develops temporarily during and towards the end of a game, and (3) defenders have lower work rates than midfielders and attackers. The difference in high-intensity running between the 2 levels demonstrates the importance of intense intermittent exercise for match performance in women......We sought to study the physical demands and match performance of women soccer players. Nineteen top-class and 15 high-level players were individually videotaped in competitive matches, and time-motion analysis were performed. The players changed locomotor activity >1,300 times in a game...... fewer (P women soccer players (1) top-class international players perform more intervals of high-intensity running than elite players at a lower level...

  20. Adequacy of Physicians Knowledge Level of Cardiopulmonary Resuscitation to Current Guidelines

    Directory of Open Access Journals (Sweden)

    Ümmu Kocalar

    2016-01-01

    Full Text Available Aim: The purpose of this study is to test the level of information on CPR and suitability to current application of the phsicians practicing in hospital ANEAH. Material and Method: The form of a test of 20 questions fort his purpose has been prepared in accordance with the 2010 AHA-ERC CPR guidelines. This form distributed to volunteer physicians to fill in. A total of 173 physicians agreed to participate in he study. The results were analyzed statistically and tried to determine the factors affecting the level of information. Results:According to the results of the study physicians gender, age and the total duration of physicians and medical asistance doesn%u2019t affect the level of information. The number of CPR within 1 month positively affect the level of knowledge. The number of theoretical and practical training in medical school, have taken the positive impact the level of knowledge of physicians. The training period after graduation, significantly increased the level of physicians information. The order of these training sessions with the asistant courses, congress, seminars and lessions on the sempozims are effective. Discussion: CPR trainig programs for physicians should be standardized, updated and expanded. Recurent in-service trainig should be provided to increase phsicians knowledge on skills.

  1. Performance-based analysis of current South African semi-trailer designs

    CSIR Research Space (South Africa)

    Thorogood, R

    2009-07-01

    Full Text Available , performance based standards, dynamic stability, tractor semi- trailers, directional response, static rollover threshold Introduction South African heavy vehicles are currently designed according to prescriptive standards designed and enforced... productivity. These include Central Tyre Inflation (CTI), on-board weighing, new materials such as Domex and vehicle satellite tracking, all leading towards increased payloads and reduced costs. There have also been improvements in technology...

  2. Fishmeal with different levels of biogenic amines in Aquafeed: Comparison of feed protein quality, fish growth performance, and metabolism

    DEFF Research Database (Denmark)

    Jasour, Mohammad Sedigh; Wagner, Liane; Sundekilde, Ulrik Kræmer

    2018-01-01

    The current study investigated the effects of fishmeal quality (low (LB) and high (HB) levels of endogenous biogenic amines) and feed extrusion temperatures (100 and 130 °C) on protein oxidation indicators and amino acids racemization (AAR) in extruded fish feed. Furthermore, the study investigated......, secondary oxidation products, and racemized methionine correlated positively with a low content of biogenic amines, whereas the primary oxidation product, protein hydroperoxides, and in vivo AAs digestibility correlated positively with high content of biogenic amines. At an extrusion temperature of 100 °C......, the growth performance of the fish decreased when the content of biogenic amines increased. In contrast, at an extrusion temperature of 130 °C, the growth performance was unaffected by the level of biogenic amines. The latter could be a consequence of the higher level of protein oxidation of LB fishmeal...

  3. Fault diagnosis and performance evaluation for high current LIA based on radial basis function neural network

    International Nuclear Information System (INIS)

    Yang Xinglin; Wang Huacen; Chen Nan; Dai Wenhua; Li Jin

    2006-01-01

    High current linear induction accelerator (LIA) is a complicated experimental physics device. It is difficult to evaluate and predict its performance. this paper presents a method which combines wavelet packet transform and radial basis function (RBF) neural network to build fault diagnosis and performance evaluation in order to improve reliability of high current LIA. The signal characteristics vectors which are extracted based on energy parameters of wavelet packet transform can well present the temporal and steady features of pulsed power signal, and reduce data dimensions effectively. The fault diagnosis system for accelerating cell and the trend classification system for the beam current based on RBF networks can perform fault diagnosis and evaluation, and provide predictive information for precise maintenance of high current LIA. (authors)

  4. Examination of the Current Approaches to State-Level Nuclear Security Evaluation

    International Nuclear Information System (INIS)

    Kim, Chan; Yim, Mansung; Kim, So Young

    2014-01-01

    An effective global nuclear materials security system will cover all materials, employ international standards and best practices, and reduce risks by reducing weapons-usable nuclear material stocks and the number of locations where they are found. Such a system must also encourage states to accept peer reviews by outside experts in order to demonstrate that effective security is in place. It is thus critically important to create an integrative framework of state-level evaluation of nuclear security as a basis for measuring the level and progress of international effort to secure and control all nuclear materials. There have been studies to represent state-level nuclear security with a quantitative metric. A prime example is the Nuclear Materials Security Index (NMSI) by the Nuclear Threat Initiative (NTI). Another comprehensive study is the State Level Risk Metric by Texas A and M University (TAMU). This paper examines the current methods with respect to their strengths and weaknesses and identifies the directions for future research to improve upon the existing approaches

  5. Stress level and academic performance of university students in ...

    African Journals Online (AJOL)

    This study examined the relationship between level of stress and students' academic performance in Universities in Kwara State, Nigeria. The study adopted a descriptive survey research design. Proportional stratified random sampling was used to select 300 students for the study. A “Students' Stress Level Questionnaire ...

  6. Josephson current and Andreev level dynamics in nanoscale superconducting weak links

    Energy Technology Data Exchange (ETDEWEB)

    Brunetti, Aldo

    2014-11-15

    In this thesis we focus on the interplay between proximity induced superconducting correlations and Coulomb interactions in a Josephson junction: i.e., in a system where two superconductors modeled as two s-wave superconductors at a phase difference φ are contacted by means of a weak link, in our case a quantum dot located in the contact. In the first part we study the Josephson current-phase relation for a multi-level quantum dot tunnel-contacted by two conventional s-waves superconductors. We determine in detail the conditions for observing a finite anomalous Josephson current, i.e. a supercurrent flowing at zero phase difference in a two-level dot with spin-orbit interactions, a weak magnetic (Zeeman) field, and in the presence of Coulomb interactions. This leads to an onset behavior I{sub a}∝sgn(B), interpreted as the sign of an incipient spontaneous breakdown of time-reversal symmetry. Moreover, we will provide conditions for realizing spatially separated - but topologically unprotected - Majorana bound states, whose signature in the system will be detectable via the current-phase relation. In the second part of the thesis, we address the Andreev bound state population dynamics in superconducting weak links (a superconducting 'atomic contact'), in which a poisoning mechanism due to the trapping of single quasiparticles can occur. Our motivation is that quantum coherent superconducting circuits are the most promising candidates for future large-scale quantum information processing devices. Moreover, quasiparticle poisoning has recently been observed in devices which contain a short superconducting weak link with few transport channels. We discuss a novel charge imbalance effect in the continuum quasiparticle population, which is due to phase fluctuations of the environment weakly coupled to the superconducting contact. This coupling enters the system as a transition rate connecting continuum quasiparticles and the Andreev bound state system. The

  7. Performance improvement by discharge from different levels in solar storage tanks

    DEFF Research Database (Denmark)

    Furbo, Simon; Andersen, Elsa; Thür, Alexander

    2005-01-01

    The thermal advantages by utilizing discharge from different levels in solar storage tanks are investigated, both for a small SDHW system and for a solar combisystem. The investigations showed that it is possible to increase the thermal performance of both types of systems by using two draw......-off levels from the solar tanks instead of one draw-off level at a fixed position. The best position of the second draw-off level is in the middle or just above the middle of the tank. For the investigated small SDHW system with a realistic draw off hot water temperature of 40°C and 45°C and an auxiliary...... volume temperature of 50.5°C the increase of the thermal performance by the second draw-off level is about 6%. For the investigated solar combisystem the extra thermal performance by using one extra draw-off level, either for the domestic hot water heat exchanger or for the heating system, is about 3...

  8. Effect of the Level of Coordinated Motor Abilities on Performance in Junior Judokas

    Science.gov (United States)

    Lech, Grzegorz; Jaworski, Janusz; Lyakh, Vladimir; Krawczyk, Robert

    2011-01-01

    The main focus of this study was to identify coordinated motor abilities that affect fighting methods and performance in junior judokas. Subjects were selected for the study in consideration of their age, competition experience, body mass and prior sports level. Subjects’ competition history was taken into consideration when analysing the effectiveness of current fight actions, and individual sports level was determined with consideration to rank in the analysed competitions. The study sought to determine the level of coordinated motor abilities of competitors. The scope of this analysis covered the following aspects: kinaesthetic differentiation, movement frequency, simple and selective reaction time (evoked by a visual or auditory stimulus), spatial orientation, visual-motor coordination, rhythmization, speed, accuracy and precision of movements and the ability to adapt movements and balance. A set of computer tests was employed for the analysis of all of the coordination abilities, while balance examinations were based on the Flamingo Balance Test. Finally, all relationships were determined based on the Spearman’s rank correlation coefficient. It was observed that the activity of the contestants during the fight correlated with the ability to differentiate movements and speed, accuracy and precision of movement, whereas the achievement level during competition was connected with reaction time. PMID:23486723

  9. Physical Characteristics and Performance of Japanese Top-Level American Football Players.

    Science.gov (United States)

    Yamashita, Daichi; Asakura, Masaki; Ito, Yoshihiko; Yamada, Shinzo; Yamada, Yosuke

    2017-09-01

    Yamashita, D, Asakura, M, Ito, Y, Yamada, S, and Yamada, Y. Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455-2461, 2017-This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (>20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance.

  10. The Concept of Performance Levels in Criterion-Referenced Assessment.

    Science.gov (United States)

    Hewitson, Mal

    The concept of performance levels in criterion-referenced assessment is explored by applying the idea to different types of tests commonly used in schools, mastery tests (including diagnostic tests) and achievement tests. In mastery tests, a threshold performance standard must be established for each criterion. Attainment of this threshold…

  11. 45 CFR 305.33 - Determination of applicable percentages based on performance levels.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF HEALTH AND HUMAN SERVICES PROGRAM PERFORMANCE MEASURES, STANDARDS, FINANCIAL INCENTIVES, AND PENALTIES § 305.33 Determination of applicable percentages based on performance levels. (a) A State's... performance levels. 305.33 Section 305.33 Public Welfare Regulations Relating to Public Welfare OFFICE OF...

  12. Objective 1: Extend Life, Improve Performance, and Maintain Safety of the Current Fleet Implementation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Robert Youngblood

    2011-01-01

    Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. By the year 2030, domestic demand for electrical energy is expected to grow to levels of 16 to 36% higher than 2007 levels. At the same time, most currently operating nuclear power plants will begin reaching the end of their 60 year operating licenses. Figure E 1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development (R&D) Roadmap has organized its activities in accordance with four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document describes how Objective 1 and the LWRS Program will be implemented. The existing U.S. nuclear fleet has a remarkable safety and performance record and today accounts for 70% of the low greenhouse

  13. Objective 1: Extend Life, Improve Performance, and Maintain Safety of the Current Fleet Implementation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Robert Youngblood

    2011-02-01

    Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. By the year 2030, domestic demand for electrical energy is expected to grow to levels of 16 to 36% higher than 2007 levels. At the same time, most currently operating nuclear power plants will begin reaching the end of their 60 year operating licenses. Figure E 1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development (R&D) Roadmap has organized its activities in accordance with four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document describes how Objective 1 and the LWRS Program will be implemented. The existing U.S. nuclear fleet has a remarkable safety and performance record and today accounts for 70% of the low greenhouse

  14. Objective 1: Extend Life, Improve Performance, and Maintain Safety of the Current Fleet; Implementation Plan

    International Nuclear Information System (INIS)

    Youngblood, Robert

    2011-01-01

    Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. By the year 2030, domestic demand for electrical energy is expected to grow to levels of 16 to 36% higher than 2007 levels. At the same time, most currently operating nuclear power plants will begin reaching the end of their 60 year operating licenses. Figure E 1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline - even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy's Research and Development (R and D) Roadmap has organized its activities in accordance with four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration's energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document describes how Objective 1 and the LWRS Program will be implemented. The existing U.S. nuclear fleet has a remarkable safety and performance record and today accounts for 70% of the low greenhouse

  15. Current and future levels of mercury atmospheric pollution on a global scale

    Science.gov (United States)

    Pacyna, Jozef M.; Travnikov, Oleg; De Simone, Francesco; Hedgecock, Ian M.; Sundseth, Kyrre; Pacyna, Elisabeth G.; Steenhuisen, Frits; Pirrone, Nicola; Munthe, John; Kindbom, Karin

    2016-10-01

    An assessment of current and future emissions, air concentrations, and atmospheric deposition of mercury worldwide is presented on the basis of results obtained during the performance of the EU GMOS (Global Mercury Observation System) project. Emission estimates for mercury were prepared with the main goal of applying them in models to assess current (2013) and future (2035) air concentrations and atmospheric deposition of this contaminant. The combustion of fossil fuels (mainly coal) for energy and heat production in power plants and in industrial and residential boilers, as well as artisanal and small-scale gold mining, is one of the major anthropogenic sources of Hg emissions to the atmosphere at present. These sources account for about 37 and 25 % of the total anthropogenic Hg emissions globally, estimated to be about 2000 t. Emissions in Asian countries, particularly in China and India, dominate the total emissions of Hg. The current estimates of mercury emissions from natural processes (primary mercury emissions and re-emissions), including mercury depletion events, were estimated to be 5207 t year-1, which represents nearly 70 % of the global mercury emission budget. Oceans are the most important sources (36 %), followed by biomass burning (9 %). A comparison of the 2035 anthropogenic emissions estimated for three different scenarios with current anthropogenic emissions indicates a reduction of these emissions in 2035 up to 85 % for the best-case scenario. Two global chemical transport models (GLEMOS and ECHMERIT) have been used for the evaluation of future mercury pollution levels considering future emission scenarios. Projections of future changes in mercury deposition on a global scale simulated by these models for three anthropogenic emissions scenarios of 2035 indicate a decrease in up to 50 % deposition in the Northern Hemisphere and up to 35 % in Southern Hemisphere for the best-case scenario. The EU GMOS project has proved to be a very important

  16. Current and future levels of mercury atmospheric pollution on a global scale

    Directory of Open Access Journals (Sweden)

    J. M. Pacyna

    2016-10-01

    Full Text Available An assessment of current and future emissions, air concentrations, and atmospheric deposition of mercury worldwide is presented on the basis of results obtained during the performance of the EU GMOS (Global Mercury Observation System project. Emission estimates for mercury were prepared with the main goal of applying them in models to assess current (2013 and future (2035 air concentrations and atmospheric deposition of this contaminant. The combustion of fossil fuels (mainly coal for energy and heat production in power plants and in industrial and residential boilers, as well as artisanal and small-scale gold mining, is one of the major anthropogenic sources of Hg emissions to the atmosphere at present. These sources account for about 37 and 25 % of the total anthropogenic Hg emissions globally, estimated to be about 2000 t. Emissions in Asian countries, particularly in China and India, dominate the total emissions of Hg. The current estimates of mercury emissions from natural processes (primary mercury emissions and re-emissions, including mercury depletion events, were estimated to be 5207 t year−1, which represents nearly 70 % of the global mercury emission budget. Oceans are the most important sources (36 %, followed by biomass burning (9 %. A comparison of the 2035 anthropogenic emissions estimated for three different scenarios with current anthropogenic emissions indicates a reduction of these emissions in 2035 up to 85 % for the best-case scenario. Two global chemical transport models (GLEMOS and ECHMERIT have been used for the evaluation of future mercury pollution levels considering future emission scenarios. Projections of future changes in mercury deposition on a global scale simulated by these models for three anthropogenic emissions scenarios of 2035 indicate a decrease in up to 50 % deposition in the Northern Hemisphere and up to 35 % in Southern Hemisphere for the best-case scenario. The EU GMOS project has

  17. The impact of educational level on performance on auditory processing tests

    Directory of Open Access Journals (Sweden)

    Cristina F.B. Murphy

    2016-03-01

    Full Text Available Research has demonstrated that a higher level of education is associated with better performance on cognitive tests among middle-aged and elderly people. However, the effects of education on auditory processing skills have not yet been evaluated. Previous demonstrations of sensory-cognitive interactions in the aging process indicate the potential importance of this topic. Therefore, the primary purpose of this study was to investigate the performance of middle-aged and elderly people with different levels of formal education on auditory processing tests. A total of 177 adults with no evidence of cognitive, psychological or neurological conditions took part in the research. The participants completed a series of auditory assessments, including dichotic digit, frequency pattern and speech-in-noise tests. A working memory test was also performed to investigate the extent to which auditory processing and cognitive performance were associated. The results demonstrated positive but weak correlations between years of schooling and performance on all of the tests applied. The factor years of schooling was also one of the best predictors of frequency pattern and speech-in-noise test performance. Additionally, performance on the working memory, frequency pattern and dichotic digit tests was also correlated, suggesting that the influence of educational level on auditory processing performance might be associated with the cognitive demand of the auditory processing tests rather than auditory sensory aspects itself. Longitudinal research is required to investigate the causal relationship between educational level and auditory processing skills.

  18. Enhancement of multitasking performance and neural oscillations by transcranial alternating current stimulation.

    Science.gov (United States)

    Hsu, Wan-Yu; Zanto, Theodore P; van Schouwenburg, Martine R; Gazzaley, Adam

    2017-01-01

    Multitasking is associated with the generation of stimulus-locked theta (4-7 Hz) oscillations arising from prefrontal cortex (PFC). Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation technique that influences endogenous brain oscillations. Here, we investigate whether applying alternating current stimulation within the theta frequency band would affect multitasking performance, and explore tACS effects on neurophysiological measures. Brief runs of bilateral PFC theta-tACS were applied while participants were engaged in a multitasking paradigm accompanied by electroencephalography (EEG) data collection. Unlike an active control group, a tACS stimulation group showed enhancement of multitasking performance after a 90-minute session (F1,35 = 6.63, p = 0.01, ηp2 = 0.16; effect size = 0.96), coupled with significant modulation of posterior beta (13-30 Hz) activities (F1,32 = 7.66, p = 0.009, ηp2 = 0.19; effect size = 0.96). Across participant regression analyses indicated that those participants with greater increases in frontal theta, alpha and beta oscillations exhibited greater multitasking performance improvements. These results indicate frontal theta-tACS generates benefits on multitasking performance accompanied by widespread neuronal oscillatory changes, and suggests that future tACS studies with extended treatments are worth exploring as promising tools for cognitive enhancement.

  19. Enhancement of multitasking performance and neural oscillations by transcranial alternating current stimulation.

    Directory of Open Access Journals (Sweden)

    Wan-Yu Hsu

    Full Text Available Multitasking is associated with the generation of stimulus-locked theta (4-7 Hz oscillations arising from prefrontal cortex (PFC. Transcranial alternating current stimulation (tACS is a non-invasive brain stimulation technique that influences endogenous brain oscillations. Here, we investigate whether applying alternating current stimulation within the theta frequency band would affect multitasking performance, and explore tACS effects on neurophysiological measures. Brief runs of bilateral PFC theta-tACS were applied while participants were engaged in a multitasking paradigm accompanied by electroencephalography (EEG data collection. Unlike an active control group, a tACS stimulation group showed enhancement of multitasking performance after a 90-minute session (F1,35 = 6.63, p = 0.01, ηp2 = 0.16; effect size = 0.96, coupled with significant modulation of posterior beta (13-30 Hz activities (F1,32 = 7.66, p = 0.009, ηp2 = 0.19; effect size = 0.96. Across participant regression analyses indicated that those participants with greater increases in frontal theta, alpha and beta oscillations exhibited greater multitasking performance improvements. These results indicate frontal theta-tACS generates benefits on multitasking performance accompanied by widespread neuronal oscillatory changes, and suggests that future tACS studies with extended treatments are worth exploring as promising tools for cognitive enhancement.

  20. High-level waste-form-product performance evaluation

    International Nuclear Information System (INIS)

    Bernadzikowski, T.A.; Allender, J.S.; Stone, J.A.; Gordon, D.E.; Gould, T.H. Jr.; Westberry, C.F. III.

    1982-01-01

    Seven candidate waste forms were evaluated for immobilization and geologic disposal of high-level radioactive wastes. The waste forms were compared on the basis of leach resistance, mechanical stability, and waste loading. All forms performed well at leaching temperatures of 40, 90, and 150 0 C. Ceramic forms ranked highest, followed by glasses, a metal matrix form, and concrete. 11 tables

  1. CURRENT ASSET TUNNELING AND FIRM PERFORMANCE IN AN EMERGING MARKET

    OpenAIRE

    Ratna Candra Sari; Zaki Baridwan

    2014-01-01

    This study examines the effect of current asset tunneling on firm performance from the emerging market perspective. Although tunneling activities is a common practices by businesses especially in Indonesia, there exist obstacles in the measurement of tunneling activity because it is difficult to proof the existence of such practices. In this study, we measure tunneling by using accounts receivables and develop tunneling detection criteria. In addition, this study examines the effect of tunnel...

  2. Phonon induced optical gain in a current carrying two-level quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Eskandari-asl, Amir, E-mail: amir.eskandari.asl@gmail.com [Department of Physics, Shahid Beheshti University, G.C. Evin, Tehran 1983963113 (Iran, Islamic Republic of); School of Nano Science, Institute for Research in Fundamental Sciences (IPM), P.O. Box: 19395-5531, Tehran, Iran (Iran, Islamic Republic of)

    2017-05-15

    In this work we consider a current carrying two level quantum dot (QD) that is coupled to a single mode phonon bath. Using self-consistent Hartree-Fock approximation, we obtain the I-V curve of QD. By considering the linear response of our system to an incoming classical light, we see that depending on the parametric regime, the system could have weak or strong light absorption or may even show lasing. This lasing occurs at high enough bias voltages and is explained by a population inversion considering side bands, while the total electron population in the higher level is less than the lower one. The frequency at which we have the most significant lasing depends on the level spacing and phonon frequency and not on the electron-phonon coupling strength.

  3. Application of Adjusted Canonical Correlation Analysis (ACCA) to study the association between mathematics in Level 1 and Level 2 and performance of engineering disciplines in Level 2

    Science.gov (United States)

    Peiris, T. S. G.; Nanayakkara, K. A. D. S. A.

    2017-09-01

    Mathematics plays a key role in engineering sciences as it assists to develop the intellectual maturity and analytical thinking of engineering students and exploring the student academic performance has received great attention recently. The lack of control over covariates motivates the need for their adjustment when measuring the degree of association between two sets of variables in Canonical Correlation Analysis (CCA). Thus to examine the individual effects of mathematics in Level 1 and Level 2 on engineering performance in Level 2, two adjusted analyses in CCA: Part CCA and Partial CCA were applied for the raw marks of engineering undergraduates for three different disciplines, at the Faculty of Engineering, University of Moratuwa, Sri Lanka. The joint influence of mathematics in Level 1 and Level 2 is significant on engineering performance in Level 2 irrespective of the engineering disciplines. The individual effect of mathematics in Level 2 is significantly higher compared to the individual effect of mathematics in Level 1 on engineering performance in Level 2. Furthermore, the individual effect of mathematics in Level 1 can be negligible. But, there would be a notable indirect effect of mathematics in Level 1 on engineering performance in Level 2. It can be concluded that the joint effect of mathematics in both Level 1 and Level 2 is immensely beneficial to improve the overall academic performance at the end of Level 2 of the engineering students. Furthermore, it was found that the impact mathematics varies among engineering disciplines. As partial CCA and partial CCA are not widely explored in applied work, it is recommended to use these techniques for various applications.

  4. High Performance Carbon Nanotube Yarn Supercapacitors with a Surface-Oxidized Copper Current Collector.

    Science.gov (United States)

    Zhang, Daohong; Wu, Yunlong; Li, Ting; Huang, Yin; Zhang, Aiqing; Miao, Menghe

    2015-11-25

    Threadlike linear supercapacitors have demonstrated high potential for constructing fabrics to power electronic textiles (eTextiles). To improve the cyclic electrochemical performance and to produce power fabrics large enough for practical applications, a current collector has been introduced into the linear supercapcitors to transport charges produced by active materials along the length of the supercapacitor with high efficiency. Here, we first screened six candidate metal filaments (Pt, Au, Ag, AuAg, PtCu, and Cu) as current collectors for carbon nanotube (CNT) yarn-based linear supercapacitors. Although all of the metal filaments significantly improved the electrochemical performance of the linear supercapacitor, two supercapacitors constructed from Cu and PtCu filaments, respectively, demonstrate far better electrochemical performance than the other four supercapacitors. Further investigation shows that the surfaces of the two Cu-containing filaments are oxidized by the surrounding polymer electrolyte in the electrode. While the unoxidized core of the Cu-containing filaments remains highly conductive and functions as a current collector, the resulting CuO on the surface is an electrochemically active material. The linear supercapacitor architecture incorporating dual active materials CNT + Cu extends the potential window from 1.0 to 1.4 V, leading to significant improvement to the energy density and power density.

  5. The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment.

    Science.gov (United States)

    Allen, Peter M; Latham, Keziah; Mann, David L; Ravensbergen, Rianne H J C; Myint, Joy

    2016-01-01

    The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle, while standing, toward a regulation target placed at the end of a 10 m shooting range. Cambridge simulation glasses were used to simulate six different levels of VI. Visual acuity (VA) and contrast sensitivity (CS) were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual's average score in every level of simulated VI and normalizing this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving 'expected' or 'below expected' shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR) is conservative, maximizing the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not actually have an impairment that impacts performance in the sport. An

  6. Level-3 Cholesky Factorization Routines Improve Performance of Many Cholesky Algorithms

    DEFF Research Database (Denmark)

    Gustavson, Fred G.; Wasniewski, Jerzy; Dongarra, Jack J.

    2013-01-01

    Four routines called DPOTF3i, i = a,b,c,d, are presented. DPOTF3i are a novel type of level-3 BLAS for use by BPF (Blocked Packed Format) Cholesky factorization and LAPACK routine DPOTRF. Performance of routines DPOTF3i are still increasing when the performance of Level-2 routine DPOTF2 of LAPACK...

  7. Enhanced Device and Circuit-Level Performance Benchmarking of Graphene Nanoribbon Field-Effect Transistor against a Nano-MOSFET with Interconnects

    Directory of Open Access Journals (Sweden)

    Huei Chaeng Chin

    2014-01-01

    Full Text Available Comparative benchmarking of a graphene nanoribbon field-effect transistor (GNRFET and a nanoscale metal-oxide-semiconductor field-effect transistor (nano-MOSFET for applications in ultralarge-scale integration (ULSI is reported. GNRFET is found to be distinctly superior in the circuit-level architecture. The remarkable transport properties of GNR propel it into an alternative technology to circumvent the limitations imposed by the silicon-based electronics. Budding GNRFET, using the circuit-level modeling software SPICE, exhibits enriched performance for digital logic gates in 16 nm process technology. The assessment of these performance metrics includes energy-delay product (EDP and power-delay product (PDP of inverter and NOR and NAND gates, forming the building blocks for ULSI. The evaluation of EDP and PDP is carried out for an interconnect length that ranges up to 100 μm. An analysis, based on the drain and gate current-voltage (Id-Vd and Id-Vg, for subthreshold swing (SS, drain-induced barrier lowering (DIBL, and current on/off ratio for circuit implementation is given. GNRFET can overcome the short-channel effects that are prevalent in sub-100 nm Si MOSFET. GNRFET provides reduced EDP and PDP one order of magnitude that is lower than that of a MOSFET. Even though the GNRFET is energy efficient, the circuit performance of the device is limited by the interconnect capacitances.

  8. Application of a modified flux-coupling type superconducting fault current limiter to transient performance enhancement of micro-grid

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Lei, E-mail: stclchen1982@163.com [School of Electrical Engineering, Wuhan University, Wuhan 430072 (China); Zheng, Feng; Deng, Changhong; Li, Shichun; Li, Miao; Liu, Hui [School of Electrical Engineering, Wuhan University, Wuhan 430072 (China); Zhu, Lin [Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville 37996 (United States); Guo, Fang [Department of Substation, Guang Dong Electric Power Design Institute, Guangzhou 510663 (China)

    2015-11-15

    Highlights: • A modified flux-coupling type SFCL is suggested to enhance the transient performance of a micro-grid. • The SFCL’s main contribution is to improve the micro-grid’s fault ride-through capability. • The SFCL also can make the micro-grid carry out a smooth transition between its grid-connected and islanded modes. • The simulations show that the SFCL can availably strengthen the micro-grid’s voltage and frequency stability. - Abstract: Concerning the application and development of a micro-grid system which is designed to accommodate high penetration of intermittent renewable resources, one of the main issues is related to an increase in the fault-current level. It is crucial to ensure the micro-grid’s operational stability and service reliability when a fault occurs in the main network. In this paper, our research group suggests a modified flux-coupling type superconducting fault current limiter (SFCL) to enhance the transient performance of a typical micro-grid system. The SFCL is installed at the point of common coupling (PCC) between the main network and the micro-grid, and it is expected to actively improve the micro-grid’s fault ride-through capability. And for some specific faults, the micro-grid should disconnect from the main network, and the SFCL’s contribution is to make the micro-grid carry out a smooth transition between its grid-connected and islanded modes. Related theory derivation, technical discussion and simulation analysis are performed. From the demonstrated results, applying the SFCL can effectively limit the fault current, maintain the power balance, and enhance the voltage and frequency stability of the micro-grid.

  9. Application of a modified flux-coupling type superconducting fault current limiter to transient performance enhancement of micro-grid

    International Nuclear Information System (INIS)

    Chen, Lei; Zheng, Feng; Deng, Changhong; Li, Shichun; Li, Miao; Liu, Hui; Zhu, Lin; Guo, Fang

    2015-01-01

    Highlights: • A modified flux-coupling type SFCL is suggested to enhance the transient performance of a micro-grid. • The SFCL’s main contribution is to improve the micro-grid’s fault ride-through capability. • The SFCL also can make the micro-grid carry out a smooth transition between its grid-connected and islanded modes. • The simulations show that the SFCL can availably strengthen the micro-grid’s voltage and frequency stability. - Abstract: Concerning the application and development of a micro-grid system which is designed to accommodate high penetration of intermittent renewable resources, one of the main issues is related to an increase in the fault-current level. It is crucial to ensure the micro-grid’s operational stability and service reliability when a fault occurs in the main network. In this paper, our research group suggests a modified flux-coupling type superconducting fault current limiter (SFCL) to enhance the transient performance of a typical micro-grid system. The SFCL is installed at the point of common coupling (PCC) between the main network and the micro-grid, and it is expected to actively improve the micro-grid’s fault ride-through capability. And for some specific faults, the micro-grid should disconnect from the main network, and the SFCL’s contribution is to make the micro-grid carry out a smooth transition between its grid-connected and islanded modes. Related theory derivation, technical discussion and simulation analysis are performed. From the demonstrated results, applying the SFCL can effectively limit the fault current, maintain the power balance, and enhance the voltage and frequency stability of the micro-grid.

  10. Correlation of Titleist Performance Institute (TPI) level 1 movement screens and golf swing faults.

    Science.gov (United States)

    Gulgin, Heather R; Schulte, Brian C; Crawley, Amy A

    2014-02-01

    Although some research in the past has examined how physical limitations in strength or flexibility affect a golfer's performance, the performance outcome most measured was driving distance. Currently, there are no data that have examined the relationship between selected strength and flexibility variables and golf swing faults. The purpose of this study was to examine the relationship between Titleist Performance Institute (TPI) level 1 movement screen variables and 14 common golf swing faults. Thirty-six male and female golfers (mean age, 25.4 ± 9.9 years; height, 175.9 ± 16.2 cm; mass, 76.2 ± 14.6 kg; handicap, 14.2 ± 10.4) participated. Twelve physical tests of strength, flexibility, and balance were assessed using the TPI level 1 golf fitness screening tool. Golfers then hit 4 golf shots (with a 5-iron) while being videoed, and those were then analyzed for 14 different golf swing faults (using V1Pro software). Three significant associations between a physical limitation and a particular golf swing fault were found: toe touch and early hip extension (p = 0.015), bridge on right side with both early hip extension (p = 0.050), and loss of posture (p = 0.028). In addition, an odds ratio showed that when a golfer could not overhead deep squat or single leg balance on left side, they were 2-3 times more likely to exhibit a early hip extension, loss of posture, or slide during the golf swing, as compared with those who could perform a correct overhead deep squat. Based on our findings, it is important for the golf fitness professional to particularly address a golfer's core strength, balance, and hamstring flexibility to help avoid common golf swing faults, which affect a golfer's ball striking ability and ultimately their performance.

  11. Performance of magneto-optical glass in optical current transducer application

    International Nuclear Information System (INIS)

    Shen, Yan; Lu, Yunhe; Liu, Zhao; Yu, Xueliang; Zhang, Guoqing; Yu, Wenbin

    2015-01-01

    First, a theoretical analysis was performed on the effect of temperature on the performance of the sensing element of paramagnetic rare earth-doped magneto-optical glass material that can be used in an optical current transducer application. The effect comprises two aspects: the linear birefringence and the Verdet constant. On this basis, rare earth-doped glass temperature characteristics were studied, and the experimental results indicated that the linear birefringence of rare earth-doped glass increased with increasing temperature, while its magneto-optical sensitivity decreased. Comparative experiments performed for various concentrations of rare earth dopant in the glass revealed that changes in the dopant concentration had no significant effect on the performance of magneto-optical glass. At last, a comparison between rare earth-doped magneto-optical and diamagnetic dense flint glass showed that the sensitivity of the former was six times that of the latter, although the temperature stability of the former was poorer. - Highlights: • Theoretical analysis on the effects of temperature on RE glass. • Rare earth doping leads to higher magneto-optical sensitivity. • The sensitivity of the RE glass is six times that of the dense flint glass

  12. Performance Evaluation of Fusing Protected Fingerprint Minutiae Templates on the Decision Level

    Directory of Open Access Journals (Sweden)

    Raymond N. J. Veldhuis

    2012-04-01

    Full Text Available In a biometric authentication system using protected templates, a pseudonymous identifier is the part of a protected template that can be directly compared. Each compared pair of pseudonymous identifiers results in a decision testing whether both identifiers are derived from the same biometric characteristic. Compared to an unprotected system, most existing biometric template protection methods cause to a certain extent degradation in biometric performance. Fusion is therefore a promising way to enhance the biometric performance in template-protected biometric systems. Compared to feature level fusion and score level fusion, decision level fusion has not only the least fusion complexity, but also the maximum interoperability across different biometric features, template protection and recognition algorithms, templates formats, and comparison score rules. However, performance improvement via decision level fusion is not obvious. It is influenced by both the dependency and the performance gap among the conducted tests for fusion. We investigate in this paper several fusion scenarios (multi-sample, multi-instance, multi-sensor, multi-algorithm, and their combinations on the binary decision level, and evaluate their biometric performance and fusion efficiency on a multi-sensor fingerprint database with 71,994 samples.

  13. Performance Evaluation of Fusing Protected Fingerprint Minutiae Templates on the Decision Level

    Science.gov (United States)

    Yang, Bian; Busch, Christoph; de Groot, Koen; Xu, Haiyun; Veldhuis, Raymond N. J.

    2012-01-01

    In a biometric authentication system using protected templates, a pseudonymous identifier is the part of a protected template that can be directly compared. Each compared pair of pseudonymous identifiers results in a decision testing whether both identifiers are derived from the same biometric characteristic. Compared to an unprotected system, most existing biometric template protection methods cause to a certain extent degradation in biometric performance. Fusion is therefore a promising way to enhance the biometric performance in template-protected biometric systems. Compared to feature level fusion and score level fusion, decision level fusion has not only the least fusion complexity, but also the maximum interoperability across different biometric features, template protection and recognition algorithms, templates formats, and comparison score rules. However, performance improvement via decision level fusion is not obvious. It is influenced by both the dependency and the performance gap among the conducted tests for fusion. We investigate in this paper several fusion scenarios (multi-sample, multi-instance, multi-sensor, multi-algorithm, and their combinations) on the binary decision level, and evaluate their biometric performance and fusion efficiency on a multi-sensor fingerprint database with 71,994 samples. PMID:22778583

  14. Electrical and Mechanical Performance of Carbon Fiber-Reinforced Polymer Used as the Impressed Current Anode Material.

    Science.gov (United States)

    Zhu, Ji-Hua; Zhu, Miaochang; Han, Ningxu; Liu, Wei; Xing, Feng

    2014-07-24

    An investigation was performed by using carbon fiber-reinforced polymer (CFRP) as the anode material in the impressed current cathodic protection (ICCP) system of steel reinforced concrete structures. The service life and performance of CFRP were investigated in simulated ICCP systems with various configurations. Constant current densities were maintained during the tests. No significant degradation in electrical and mechanical properties was found for CFRP subjected to anodic polarization with the selected applied current densities. The service life of the CFRP-based ICCP system was discussed based on the practical reinforced concrete structure layout.

  15. CURRENT ASSET TUNNELING AND FIRM PERFORMANCE IN AN EMERGING MARKET

    Directory of Open Access Journals (Sweden)

    Ratna Candra Sari

    2014-12-01

    Full Text Available This study examines the effect of current asset tunneling on firm performance from the emerging market perspective. Although tunneling activities is a common practices by businesses especially in Indonesia, there exist obstacles in the measurement of tunneling activity because it is difficult to proof the existence of such practices. In this study, we measure tunneling by using accounts receivables and develop tunneling detection criteria. In addition, this study examines the effect of tunneling on firm performance and market reaction during the announcement of the related party transaction. The study finds that from the perspective of the being-tunneled companies, receivables to related parties negatively affect the company’s profit margin. Companies which announce related party transaction indicating tunneling obtain negative abnormal return during the announcement of the related party transaction.

  16. A Refined Self-Tuning Filter-Based Instantaneous Power Theory Algorithm for Indirect Current Controlled Three-Level Inverter-Based Shunt Active Power Filters under Non-sinusoidal Source Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Yap Hoon

    2017-02-01

    Full Text Available In this paper, a refined reference current generation algorithm based on instantaneous power (pq theory is proposed, for operation of an indirect current controlled (ICC three-level neutral-point diode clamped (NPC inverter-based shunt active power filter (SAPF under non-sinusoidal source voltage conditions. SAPF is recognized as one of the most effective solutions to current harmonics due to its flexibility in dealing with various power system conditions. As for its controller, pq theory has widely been applied to generate the desired reference current due to its simple implementation features. However, the conventional dependency on self-tuning filter (STF in generating reference current has significantly limited mitigation performance of SAPF. Besides, the conventional STF-based pq theory algorithm is still considered to possess needless features which increase computational complexity. Furthermore, the conventional algorithm is mostly designed to suit operation of direct current controlled (DCC SAPF which is incapable of handling switching ripples problems, thereby leading to inefficient mitigation performance. Therefore, three main improvements are performed which include replacement of STF with mathematical-based fundamental real power identifier, removal of redundant features, and generation of sinusoidal reference current. To validate effectiveness and feasibility of the proposed algorithm, simulation work in MATLAB-Simulink and laboratory test utilizing a TMS320F28335 digital signal processor (DSP are performed. Both simulation and experimental findings demonstrate superiority of the proposed algorithm over the conventional algorithm.

  17. Exploratory Study on the Impact of Information on Performance Psychology on Stress and Anxiety Levels of Brazilian Music Performers

    Directory of Open Access Journals (Sweden)

    Sonia Ray

    2016-12-01

    Full Text Available This paper examines the impact of information on psychology of music on Stress and Anxiety Levels of Brazilian students of music performance, both undergraduate and graduate, and cross information on their levels of stress and anxiety. It includes an investigation on curricular programs of Brazilian public universities based on previous investigation by the authors (RAY; et al, 2011. The main goals: 1 to investigate how much information Brazilian music performance students has access to access during their courses; and 2 to identify potential indicators of the impact this information may have on the levels of stress and anxiety in the performances of these students; Methodology:  Students from six Brazilian public universities were requested to fill out three forms: the Kenny Music Performance Anxiety Inventory (K-MPAI; the Inventory of Stress Symptoms LIPP and an additional form that investigated the participants routine for preparation to performance. Results: information on music performance psychology is only presented privately at teacher’s discretion. As compulsory classes have not been included in the curriculum, it was not possible to infer results on this subject. More than half of the participants (51,72% don’t present stress condition. Almost half of them (48,27% have some level of stress. All participants fit within some level of anxiety.

  18. Evaluation of the performance degradation at PAFC effect of electrolyte fill-level on electrode performance

    Energy Technology Data Exchange (ETDEWEB)

    Kitai, Takashi; Uchida, Hiroyuki; Watanabe, Masahiro [Yamanashi Univ., Kofu (Japan)] [and others

    1996-12-31

    As a complimentary research project to the demonstration project of 5MW and 1MW PAFC plants, the mechanism and rate of deterioration of the cells and stacks have been studied from 1995 FY, with the objective of establishing an estimation method for the service life-time of the cell stacks. This work has been performed in the Basic Research Project, as part of that project on PAFC`s, selecting four subjects (Electrocatalysts degradation, Electrolyte fill-level, Cell material corrosion, Electrolyte loss) as the essential factors relating to the life-time. In this report, we will exhibit the effect of the electrolyte fill-level on the electrode performances.

  19. Relative merits of size, field, and current on ignited tokamak performance

    International Nuclear Information System (INIS)

    Uckan, N.A.

    1988-01-01

    A simple global analysis is developed to examine the relative merits of size (L = a or R/sub 0 /), field (B/sub 0 /), and current (I) on ignition regimes of tokamaks under various confinement scaling laws. Scalings of key parameters with L, B/sub 0 /, and I are presented at several operating points, including (a) optimal path to ignition (saddle point), (b) ignition at minimum beta, (c) ignition at 10 keV, and (d) maximum performance at the limits of density and beta. Expressions for the saddle point and the minimum conditions needed for ohmic ignition are derived analytically for any confinement model of the form tau/sub E/ ∼ n/sup x/T/sup y/. For a wide range of confinement models, the ''figure of merit'' parameters and I are found to give a good indication of the relative performance of the devices where q* is the cylindrical safety factor. As an illustration, the results are applied to representative ''CIT'' (as a class of compact, high-field ignition tokamaks) and ''Super-JETs'' [a class of large-size (few x JET), low-field, high-current (≥20-MA) devices.

  20. Trunk Stability, Trunk Strength and Sport Performance Level in Judo.

    Directory of Open Access Journals (Sweden)

    David Barbado

    Full Text Available Although trunk muscle function has been suggested to be a determinant of judo performance, its contribution to high-level performance in this sport has been poorly studied. Therefore, several tests were used to assess the differences in trunk muscle function between 11 international and 14 national level judo practitioners (judokas. Trunk strength and endurance were assessed using isokinetic tests and core stability was assessed using two protocols: 1 sudden loading, to assess trunk responses to unexpected external perturbations; 2 stable and unstable sitting, to assess the participants' ability to control trunk balance. No differences between groups were found for trunk flexor isokinetic strength, trunk responses against lateral and posterior loading and trunk control while sitting. However, international level judokas showed significantly higher trunk extensor isokinetic strength (p <0.05 and lower trunk angular displacement after anterior trunk loading (p <0.05 than national level judokas. Few and low (r < 0.512 significant correlations were found between strength, endurance and stability parameters, which suggests that trunk strength and endurance are not limiting factors for trunk stability in competitive judokas. These results support the importance of trunk extensor strength and trunk stability against forward perturbations in elite judo performance.

  1. Steady-state and transient performance of HVDC link based 3-level ...

    African Journals Online (AJOL)

    Administrateur

    DC (HVDC) transmission systems based on three-level voltage source converters. The study involves ..... voltage drops due to the currents across the impedance .... IEEE/PES Transmission and Distribution Conference &. Exhibition: Asia and ...

  2. Prediction of SFL Interruption Performance from the Results of Arc Simulation during High-Current Phase

    Science.gov (United States)

    Lee, Jong-Chul; Lee, Won-Ho; Kim, Woun-Jea

    2015-09-01

    The design and development procedures of SF6 gas circuit breakers are still largely based on trial and error through testing although the development costs go higher every year. The computation cannot cover the testing satisfactorily because all the real processes arc not taken into account. But the knowledge of the arc behavior and the prediction of the thermal-flow inside the interrupters by numerical simulations are more useful than those by experiments due to the difficulties to obtain physical quantities experimentally and the reduction of computational costs in recent years. In this paper, in order to get further information into the interruption process of a SF6 self-blast interrupter, which is based on a combination of thermal expansion and the arc rotation principle, gas flow simulations with a CFD-arc modeling are performed during the whole switching process such as high-current period, pre-current zero period, and current-zero period. Through the complete work, the pressure-rise and the ramp of the pressure inside the chamber before current zero as well as the post-arc current after current zero should be a good criterion to predict the short-line fault interruption performance of interrupters.

  3. Electrical and Mechanical Performance of Carbon Fiber-Reinforced Polymer Used as the Impressed Current Anode Material

    Directory of Open Access Journals (Sweden)

    Ji-Hua Zhu

    2014-07-01

    Full Text Available An investigation was performed by using carbon fiber-reinforced polymer (CFRP as the anode material in the impressed current cathodic protection (ICCP system of steel reinforced concrete structures. The service life and performance of CFRP were investigated in simulated ICCP systems with various configurations. Constant current densities were maintained during the tests. No significant degradation in electrical and mechanical properties was found for CFRP subjected to anodic polarization with the selected applied current densities. The service life of the CFRP-based ICCP system was discussed based on the practical reinforced concrete structure layout.

  4. Self-regulation of learning and performance level of elite youth soccer players

    NARCIS (Netherlands)

    Toering, Tynke; Elferink-Gemser, Marije T.; Jordet, Geir; Pepping, Gert-Jan; Visscher, Chris

    2012-01-01

    This study examined the relationship between self-regulated learning and performance level of 256 elite youth soccer players aged 12 to 17 years (M-age = 14.2; SD = 1.2). As relative age may affect this relationship through its association with maturation, experience, and performance level, we

  5. Currently used dosage regimens of vancomycin fail to achieve therapeutic levels in approximately 40% of intensive care unit patients.

    Science.gov (United States)

    Obara, Vitor Yuzo; Zacas, Carolina Petrus; Carrilho, Claudia Maria Dantas de Maio; Delfino, Vinicius Daher Alvares

    2016-01-01

    This study aimed to assess whether currently used dosages of vancomycin for treatment of serious gram-positive bacterial infections in intensive care unit patients provided initial therapeutic vancomycin trough levels and to examine possible factors associated with the presence of adequate initial vancomycin trough levels in these patients. A prospective descriptive study with convenience sampling was performed. Nursing note and medical record data were collected from September 2013 to July 2014 for patients who met inclusion criteria. Eighty-three patients were included. Initial vancomycin trough levels were obtained immediately before vancomycin fourth dose. Acute kidney injury was defined as an increase of at least 0.3mg/dL in serum creatinine within 48 hours. Considering vancomycin trough levels recommended for serious gram-positive infection treatment (15 - 20µg/mL), patients were categorized as presenting with low, adequate, and high vancomycin trough levels (35 [42.2%], 18 [21.7%], and 30 [36.1%] patients, respectively). Acute kidney injury patients had significantly greater vancomycin trough levels (p = 0.0055, with significance for a trend, p = 0.0023). Surprisingly, more than 40% of the patients did not reach an effective initial vancomycin trough level. Studies on pharmacokinetic and dosage regimens of vancomycin in intensive care unit patients are necessary to circumvent this high proportion of failures to obtain adequate initial vancomycin trough levels. Vancomycin use without trough serum level monitoring in critically ill patients should be discouraged.

  6. Employee performance appraisal and productivity levels in selected ...

    African Journals Online (AJOL)

    The focus of this study was on performance appraisal of academic staff of Universities in Nigeria and their productivity levels. The prime problem that necessitated this study was to examine the effectiveness of the subjective methods used in appraising qualitative work attributes of the employees and to assess the extent to ...

  7. System-level techniques for analog performance enhancement

    CERN Document Server

    Song, Bang-Sup

    2016-01-01

    This book shows readers to avoid common mistakes in circuit design, and presents classic circuit concepts and design approaches from the transistor to the system levels. The discussion is geared to be accessible and optimized for practical designers who want to learn to create circuits without simulations. Topic by topic, the author guides designers to learn the classic analog design skills by understanding the basic electronics principles correctly, and further prepares them to feel confident in designing high-performance, state-of-the art CMOS analog systems. This book combines and presents all in-depth necessary information to perform various design tasks so that readers can grasp essential material, without reading through the entire book. This top-down approach helps readers to build practical design expertise quickly, starting from their understanding of electronics fundamentals. .

  8. The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting With Vision Impairment

    Directory of Open Access Journals (Sweden)

    Peter M Allen

    2016-11-01

    Full Text Available The aim of this study was to investigate the level of vision impairment that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI shooting. Nineteen international-level shooters without vision impairment took part in the study. Participants shot an air rifle, while standing, towards a regulation target placed at the end of a 10m shooting range. Cambridge simulation glasses were used to simulate six different levels of vision impairment. Visual acuity (VA and contrast sensitivity (CS were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual’s average score in every level of simulated vision impairment and normalising this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic (ROC curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving ‘expected’ or ‘below expected’ shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR is conservative, maximising the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not

  9. Occurrence of lead-related symptoms below the current occupational safety and health act allowable blood lead levels.

    Science.gov (United States)

    Rosenman, Kenneth D; Sims, Amy; Luo, Zhehui; Gardiner, Joseph

    2003-05-01

    To determine the occurrence of symptoms of lead toxicity at levels below the current allowable Occupational Safety and Health Act blood lead level of 50 micrograms/dL, standardized telephone interviews were conducted of individuals reported to a statewide laboratory-based surveillance system. Four hundred and ninety-seven, or 75%, of the eligible participants were interviewed. Gastrointestinal, musculoskeletal, and nervous system symptoms increased with increasing blood lead levels. Nervous, gastrointestinal, and musculoskeletal symptoms all began to be increased in individuals with blood leads between 30-39 micrograms/dL and possibly at levels as low as 25-30 micrograms/dL for nervous system symptoms. The results of this study of increased symptoms are consistent with and provide added weight to previous results showing subclinical changes in the neurologic and renal systems and sperm counts at blood lead levels currently allowed by the Occupational Safety and Health Act.

  10. A preliminary parametric performance assessment for the disposal of alpha-contaminated mixed low-level waste stored at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Smith, T.H.; Anderson, G.L.; Myers, J.

    1995-01-01

    A preliminary parametric performance assessment (PA) has been performed of potential waste disposal systems for alpha-contaminated mixed low-level waste (ALLW) currently stored at the Idaho National Engineering Laboratory. The radionuclide-confinement performance of treated ALLW in various final waste forms, in various disposal locations, and under various assumptions was evaluated. Compliance with performance objectives was assessed for the undisturbed waste scenario and for intrusion scenarios. Some combinations of final waste form, disposal site, and environmental transport assumptions lead to calculated does that comply with the performance objectives, while others do not. The results will help determine the optimum degree of ALLW immobilization to satisfy the performance objectives while minimizing cost

  11. GABA level, gamma oscillation, and working memory performance in schizophrenia.

    Science.gov (United States)

    Chen, Chi-Ming A; Stanford, Arielle D; Mao, Xiangling; Abi-Dargham, Anissa; Shungu, Dikoma C; Lisanby, Sarah H; Schroeder, Charles E; Kegeles, Lawrence S

    2014-01-01

    A relationship between working memory impairment, disordered neuronal oscillations, and abnormal prefrontal GABA function has been hypothesized in schizophrenia; however, in vivo GABA measurements and gamma band neural synchrony have not yet been compared in schizophrenia. This case-control pilot study (N = 24) compared baseline and working memory task-induced neuronal oscillations acquired with high-density electroencephalograms (EEGs) to GABA levels measured in vivo with magnetic resonance spectroscopy. Working memory performance, baseline GABA level in the left dorsolateral prefrontal cortex (DLPFC), and measures of gamma oscillations from EEGs at baseline and during a working memory task were obtained. A major limitation of this study is a relatively small sample size for several analyses due to the integration of diverse methodologies and participant compliance. Working memory performance was significantly lower for patients than for controls. During the working memory task, patients (n = 7) had significantly lower amplitudes in gamma oscillations than controls (n = 9). However, both at rest and across working memory stages, there were significant correlations between gamma oscillation amplitude and left DLPFC GABA level. Peak gamma frequency during the encoding stage of the working memory task (n = 16) significantly correlated with GABA level and working memory performance. Despite gamma band amplitude deficits in patients across working memory stages, both baseline and working memory-induced gamma oscillations showed strong dependence on baseline GABA levels in patients and controls. These findings suggest a critical role for GABA function in gamma band oscillations, even under conditions of system and cognitive impairments as seen in schizophrenia.

  12. Extrapolating power-ramp performance criteria for current and advanced CANDU fuels

    Energy Technology Data Exchange (ETDEWEB)

    Tayal, M.; Chassie, G.G

    2000-06-01

    To improve the precision and accuracy of power-ramp performance criteria for high-burnup fuel, we have examined in-reactor fuel performance data as well as out-reactor test data. The data are consistent with some of the concepts used in the current formulations for defining fuel failure thresholds, such as size of power-ramp and extent of burnup. Our review indicates that there is a need to modify some other aspects of the current formulations; therefore, a modified formulation is presented in this paper. The improvements mainly concern corrodent concentration and its relationships with threshold stress for failure. The new formulation is consistent with known and expected trends such as strength of Zircaloy in corrosive environment, timing of the release of fission products to the pellet-to-sheath gap, CANLUB coating, and fuel burnup. Because of the increased precision and accuracy, the new formulation is better able to identify operational regimes that are at risk of power-ramp failures; this predictive ability provides enhanced protection to fuel against power-ramp defects. At die same time, by removing unnecessary conservatisms in other areas, the new formulation permits a greater range of defect-free operational envelope as well as larger operating margins in regions that are, in fact, not prone to power-ramp failures. (author)

  13. Lawrence Livermore National Laboratory low-level waste systems performance assessment

    International Nuclear Information System (INIS)

    1990-11-01

    This Low-Level Radioactive Waste (LLW) Systems Performance Assessment (PA) presents a systematic analysis of the potential risks posed by the Lawrence Livermore National Laboratory (LLNL) waste management system. Potential risks to the public and environment are compared to established performance objectives as required by DOE Order 5820.2A. The report determines the associated maximum individual committed effective dose equivalent (CEDE) to a member of the public from LLW and mixed waste. A maximum annual CEDE of 0.01 mrem could result from routine radioactive liquid effluents. A maximum annual CEDE of 0.003 mrem could result from routine radioactive gaseous effluents. No other pathways for radiation exposure of the public indicated detectable levels of exposure. The dose rate, monitoring, and waste acceptance performance objectives were found to be adequately addressed by the LLNL Program. 88 refs., 3 figs., 17 tabs

  14. Effects of Varying Gravity Levels on fNIRS Headgear Performance and Signal Recovery

    Science.gov (United States)

    Mackey, Jeffrey R.; Harrivel, Angela R.; Adamovsky, Grigory; Lewandowski, Beth E.; Gotti, Daniel J.; Tin, Padetha; Floyd, Bertram M.

    2013-01-01

    This paper reviews the effects of varying gravitational levels on functional Near-Infrared Spectroscopy (fNIRS) headgear. The fNIRS systems quantify neural activations in the cortex by measuring hemoglobin concentration changes via optical intensity. Such activation measurement allows for the detection of cognitive state, which can be important for emotional stability, human performance and vigilance optimization, and the detection of hazardous operator state. The technique depends on coupling between the fNIRS probe and users skin. Such coupling may be highly susceptible to motion if probe-containing headgear designs are not adequately tested. The lack of reliable and self-applicable headgear robust to the influence of motion artifact currently inhibits its operational use in aerospace environments. Both NASAs Aviation Safety and Human Research Programs are interested in this technology as a method of monitoring cognitive state of pilots and crew.

  15. CURRENT LEVELS OF MEDICAL EXPOSURE IN RUSSIA

    Directory of Open Access Journals (Sweden)

    M. I. Balonov

    2015-01-01

    Full Text Available We considered conditions of patients’ medical radiation exposure in Russian diagnostic radiology and nuclear medicine basing on the data of our own research, of the Unified system of individual dose control and of some relevant literature. We analyzed the data on the number of diagnostic examinations, patients’ individual and collective doses and their distribution by examination types. Time trends of the studied parameters are presented for the period between 1999 and 2013. Current level of Russian patients’ medical exposure is the lowest over the whole observation period and one of the lowest among the developed countries. The annual number of X-ray diagnostic examinations is 1.8 per capita. In 2013 median effective dose of medical exposure per capita in Russia was 0.45 mSv and median dose per procedure was 0.25 mSv. The major contribution to collective dose of medical exposure was from computed tomography and radiography; the largest individual doses were caused by interventional radiology, computed X-Ray and nuclear medicine tomographic examinations. The range of median doses comprises about four orders of magnitude, i.e. from several microSv in dental X-ray examinations up to several tens of milliSv in interventional and multistage tomographic examinations. The median effective dose of adult patients increases by about an order of magnitude with each transition from dental X-ray examinations to conventional radiology and further to computed tomography and interventional radiology examinations. During interventional X-Ray examinations, absorbed skin doses at radiation beam entrance site may reach several Gray, which may lead to deterministic radiation effects in skin and subcutaneous tissues. Due to replacement of low-dose ‘functional’ nuclear medicine examinations with more informative modern scintigraphy and tomography examination, patient doses substantially increased over the last decade. With current trend for re-equipment of

  16. Performance assessment of a dynamic current allocator for the JET eXtreme Shape Controller

    International Nuclear Information System (INIS)

    Varano, G.; Ambrosino, G.; Tommasi, G.De; Galeani, S.; Pironti, A.; Zaccarian, L.

    2011-01-01

    This paper reports on a recently proposed dynamic allocation technique that can be effectively adopted to handle the current saturations of the Poloidal Field coils with the eXtreme Shape Controller. The proposed approach allows to automatically relax the plasma shape regulation when the reference shape requires current levels out of the available ranges, finding in real-time an optimal trade-off between shape control precision and currents saturation avoidance. In this paper the results attained during preliminary analysis are presented, showing the advantage arising from the use of the dynamic allocator, versus the bare use of the eXtreme Shape Controller.

  17. Assessment of U.S. firm-level climate change performance and strategy

    International Nuclear Information System (INIS)

    Yu, Yu; Wang, Derek D.; Li, Shanling; Shi, Qinfen

    2016-01-01

    Climate change is becoming an increasingly critical concern for human society. While there has been a great deal of research on climate change performance at the country/region level, our research focuses on the study of firm-level environmental efficiency as a proxy for firms' climate change management. Using a unique data set on U.S. S&P 500 firms for the period 2012–2013 and DEA slack-based models, we obtain firms' environmental efficiencies in six sectors. The results show significant performance dispersions both across and within the sectors. We highlight each sector's pros and cons in the environmental performance and propose guidelines for policy makers to further improve climate change performance. We also evaluate firms' operational performance and propose a unified performance measure by integrating operational and environmental efficiencies. Overall, we find there is no significant relationship between operational and environmental efficiencies in any of the six industrial sectors under study. The unified performance measures are more driven by the environmental efficiency than the operational efficiency. - Highlights: •U.S. firms have large variations in climate performance across/within the sectors. •Relationship between operational and climate performances is not significant. •The operational and climate performances can be captured in a unified measure.

  18. The Power of Individual-level Drivers of Inventive Performance

    DEFF Research Database (Denmark)

    Zwick, Thomas; Frosch, Katharina; Hoisl, Karin

    2017-01-01

    (KSAO) model. We link survey information spanning the inventors’ entire careers and psychometric test evidence with patent history data for more than 1000 inventors. We also control for variables that have traditionally been used in studies of inventive performance including inventor age, applicant type......, technology, patent, and time information. We show that educational level, skills acquired during the career, personality traits, career motivation, cognitive ability, and cognitive problem-solving style are significantly related to inventive performance....

  19. Performance of Mashona doelings supplemented with different levels of velvet bean (Mucuna pruriens L. DC. var. utilis) seed meal.

    Science.gov (United States)

    Madzimure, James; Mutema, Nyasha; Chimonyo, Michael; Bakare, Archibold Garikai; Mapiye, Cletos

    2014-06-01

    The objective of the current study was to evaluate the effects of feeding increasing levels of velvet bean seed meal (VBM; 0, 12, 24, and 36 %) on the performance of Mashona doelings. Dry matter intake was lower (P < 0.05) for the control diet compared to VBM diets, but linearly declined (P < 0.05) with increasing levels of VBM. Average daily weight gain was significantly different between experimental groups. Doelings' final live weights and average daily gains were slightly higher in control group than other three supplemented groups where they linearly declined (P < 0.05) with increasing levels of VBM. The cost per kilogram of feed, however, decreased with high inclusion level of VBM. Result suggested that high inclusion level of VBM negatively influenced the growth of young goats probably due to the presence of some anti-nutritional factors which needs further investigation.

  20. Association between mental disorders, cognitive disturbances and vitamin D serum level: Current state.

    Science.gov (United States)

    Lerner, Paul P; Sharony, Laura; Miodownik, Chanoch

    2018-02-01

    Vitamin D deficiency has been identified as a global problem. Approximately 14% of the world population has inadequate vitamin D levels. This vitamin has been usually associated with bone disorders such as rickets, osteomalacia, and osteoporosis. However, these disorders present only a small part of all the disturbances which can be induced by its deficiency. Low serum vitamin D is associated with development of cardiovascular diseases, hypertension, neurodegenerative diseases, diabetes mellitus, metabolic syndrome and even cancer. This vitamin may be an important factor in the development of psychiatric illnesses, therefore clinicians should not leave this serious issue unresolved. The aim of this review is to describe the current data concerning the association between vitamin D serum levels, cognition and mental disorders. We conducted a systematic bibliographical research, of PubMed, MedLine literature and Cochrane database without language restriction to identify all publications concerning this issue from 1995 to the first quarter of 2017. We found 48,937 articles concerning vitamin D, published during the last 22 years and 3 months (1995-2017). We selected only those publications focused on the association between vitamin D serum deficiency and mental disturbances (depression, schizophrenia, cognitive disturbances, attention deficit disorder, and autism). One hundred and sixty-seven papers were found suitable to our selection criteria. Careful evaluation of the relevant literature demonstrates that addition of vitamin D to conventional antidepressive agents can improve antidepressive effect in contrast to placebo. Regarding other mental conditions there are no clear-cut conclusions. An association between low vitamin D serum levels and different mental disorders was found. Yet, nonetheless there is no clear consensus that addition of vitamin D improves or is related to a beneficial effect on mental health. More randomized clinical control trials should be

  1. Current status of high level radioactive waste disposal in Japan and foreign countries

    International Nuclear Information System (INIS)

    Tanaka, Satoru; Tanabe, Hiromi; Inagaki, Yusuke; Ishida, Hisahiro; Kato, Osamu; Kurata, Mitsuyuki; Yamachika, Hidehiko

    2002-01-01

    At a time point of 2002, there is no country actually disposing high level radioactive wastes into grounds, but in most of countries legislative preparation and practicing agents are carried out and site selection is promoted together with energetic advancement of its R and Ds. As disposal methods of the high level radioactive wastes, various methods such as space disposal, oceanic bottom disposal, ice bed disposal, ground disposal, and so on have been examined. And, a processing technology called partitioning and transmutation technology separating long-lived radionuclides from liquid high level radioactive waste and transmutation into short-lived or harmless radionuclides has also been studied. Here was introduced their wrestling conditions in Japan and main foreign countries, as a special issue of the Current status of high level radioactive waste disposal in Japan and foreign countries'. The high level radioactive wastes (glassification solids or spent nuclear fuels) are wastes always formed by nuclear power generation and establishment of technologies is an important subject for nuclear fuel cycle. (G.K.)

  2. Calculation of the non-inductive current profile in high-performance NSTX plasmas

    Science.gov (United States)

    Gerhardt, S. P.; Fredrickson, E.; Gates, D.; Kaye, S.; Menard, J.; Bell, M. G.; Bell, R. E.; Le Blanc, B. P.; Kugel, H.; Sabbagh, S. A.; Yuh, H.

    2011-03-01

    The constituents of the current profile have been computed for a wide range of high-performance plasmas in NSTX (Ono et al 2000 Nucl. Fusion 40 557); these include cases designed to maximize the non-inductive fraction, pulse length, toroidal-β or stored energy. In the absence of low-frequency MHD activity, good agreement is found between the reconstructed current profile and that predicted by summing the independently calculated inductive, pressure-driven and neutral beam currents, without the need to invoke any anomalous beam ion diffusion. Exceptions occur, for instance, when there are toroidal Alfvén eigenmode avalanches or coupled m/n = 1/1 + 2/1 kink-tearing modes. In these cases, the addition of a spatially and temporally dependent fast-ion diffusivity can reduce the core beam current drive, restoring agreement between the reconstructed profile and the summed constituents, as well as bringing better agreement between the simulated and measured neutron emission rate. An upper bound on the fast-ion diffusivity of ~0.5-1 m2 s-1 is found in 'MHD-free' discharges, based on the neutron emission, the time rate of change in the neutron signal when a neutral beam is stepped and reconstructed on-axis current density.

  3. Calculation of the Non-Inductive Current Profile in High-Performance NSTX Plasmas

    International Nuclear Information System (INIS)

    Gerhardt, S.P.; Fredrickson, E.; Gates, D.; Kaye, S.; Menard, J.; Bell, M.G.; Bell, R.E.; Le Blanc, B.P.; Kugel, H.; Sabbagh, S.A.; Yuh, H.

    2011-01-01

    The constituents of the current profile have been computed for a wide range of high-performance plasmas in NSTX [M. Ono, et al., Nuclear Fusion 40, 557 (2000)]; these include cases designed to maximize the non-inductive fraction, pulse length, toroidal-β, or stored energy. In the absence of low-frequency MHD activity, good agreement is found between the reconstructed current profile and that predicted by summing the independently calculated inductive, pressure-driven, and neutral beam currents, without the need to invoke any anomalous beam ion diffusion. Exceptions occur, for instance, when there are toroidal Alfven eigenmode avalanches or coupled m/n=1/1+2/1 kink-tearing modes. In these cases, the addition of a spatially and temporally dependent fast ion diffusivity can reduce the core beam current drive, restoring agreement between the reconstructed profile and the summed constituents, as well as bringing better agreement between the simulated and measured neutron emission rate. An upper bound on the fast ion diffusivity of ∼0.5-1 m 2 /sec is found in 'MHD-free' discharges, based on the neutron emission, time rate of change of the neutron signal when a neutral beam is stepped, and reconstructed on-axis current density.

  4. Current trends in pedicle screw stimulation techniques: lumbosacral, thoracic, and cervical levels.

    Science.gov (United States)

    Isley, Michael R; Zhang, Xiao-Feng; Balzer, Jeffrey R; Leppanen, Ronald E

    2012-06-01

    Unequivocally, pedicle screw instrumentation has evolved as a primary construct for the treatment of both common and complex spinal disorders. However an inevitable and potentially major complication associated with this type of surgery is misplacement of a pedicle screw(s) which may result in neural and vascular complications, as well as impair the biomechanical stability of the spinal instrumentation resulting in loss of fixation. In light of these potential surgical complications, critical reviews of outcome data for treatment of chronic, low-back pain using pedicle screw instrumentation concluded that "pedicle screw fixation improves radiographically demonstrated fusion rates;" however the expense and complication rates for such constructs are considerable in light of the clinical benefit (Resnick et al. 2005a). Currently, neuromonitoring using free-run and evoked (triggered) electromyography (EMG) is widely used and advocated for safer and more accurate placement of pedicle screws during open instrumentation procedures, and more recently, guiding percutaneous placement (minimally invasive) where the pedicle cannot be easily inspected visually. The latter technique, evoked or triggered EMG when applied to pedicle screw instrumentation surgeries, has been referred to as the pedicle screw stimulation technique. As concluded in the Position Statement by the American Society of Neurophysiological Monitoring (ASNM), multimodality neuromonitoring using free-run EMG and the pedicle screw stimulation technique was considered a practice option and not yet a standard of care (Leppanen 2005). Subsequently, the American Association of Neurological Surgeons/Congress of Neurological Surgeons (AANS/CNS) Joint Section on Disorders of the Spine and Peripheral Nerves published their "Guidelines for the Performance of Fusion Procedures for Degenerative Disease of the Lumbar Spine" (Heary 2005, Resnick et al. 2005a, Resnick et al. 2005b). It was concluded that the "primary

  5. A gross anatomy flipped classroom effects performance, retention, and higher-level thinking in lower performing students.

    Science.gov (United States)

    Day, Leslie J

    2018-01-22

    A flipped classroom is a growing pedagogy in higher education. Many research studies on the flipped classroom have focused on student outcomes, with the results being positive or inconclusive. A few studies have analyzed confounding variables, such as student's previous achievement, or the impact of a flipped classroom on long-term retention and knowledge transfer. In the present study, students in a Doctor of Physical Therapy program in a traditional style lecture of gross anatomy (n = 105) were compared to similar students in a flipped classroom (n = 112). Overall, students in the flipped anatomy classroom had an increase in semester average grades (P = 0.01) and performance on higher-level analytical questions (P flipped anatomy classroom performing at a higher level in kinesiology (P flipped anatomy class, outperformed their traditional anatomy class counterparts in anatomy semester grades (P flipped classroom may benefit lower performing student's knowledge acquisition and transfer to a greater degree than higher performing students. Future studies should explore the underlying reasons for improvement in lower performing students. Anat Sci Educ. © 2018 American Association of Anatomists. © 2018 American Association of Anatomists.

  6. REMPAN at international level: current status

    International Nuclear Information System (INIS)

    Souchkevitch, Guennadi

    1997-01-01

    This document describes the current status of the Radiation Emergency medical Preparedness and Assistance Network - REMPAN, for the promotion of radiation emergency medical and public health preparedness and for practical assistance and advising countries, in a case of overexposure from any sources of radiation, by initiative of the World Health Organization - WHO

  7. Fermi level splitting and thermionic current improvement in low-dimensional multi-quantum-well (MQW) p-i-n structures

    International Nuclear Information System (INIS)

    Varonides, Argyrios C.

    2006-01-01

    Photo-excitation and subsequent thermionic currents are essential components of photo-excited carrier transport in multi-quantum-well photovoltaic (hetero-PV) structures. p-i-n multi-quantum structures are useful probes for a better understanding of PV device properties. Illumination of the intrinsic region of p-i-n multi-structures causes carrier trapping in any of the quantum wells, and subsequent carrier recombination or thermal escape is possible. At the vicinity of a quantum well, we find that the (quasi) Fermi levels undergo an upward split by a small, but non-negligible, energy amount ΔE F in the order of 12 meV. We conclude this fact by comparing the photo-excited carriers trapped in a quantum well, under illumination, to the carrier concentrations under dark. Based on such a prediction, we subsequently relate thermionic current density dependence on Fermi level splitting, concluding that excess thermal currents may increase by a factor of the order of 2. We conclude that illumination causes (a) Fermi level separation and (b) an apparent increase in thermionic currents

  8. Level-1 E/Gamma performance on 2017 data

    CERN Document Server

    CMS Collaboration

    2018-01-01

    In $2017$, the LHC achieved an instantaneous luminosity of $2\\times10^{34}cm^{-2}s^{-1}$ with an average peak number of pile-up interactions of over $50$. This document includes studies of the performance of the CMS Level-1 Calorimeter Trigger for electrons and photons. The plots are made using the full dataset of $2017$ with $41.3$ $fb^{-1}$.

  9. A performance assessment methodology for low-level radioactive waste disposal

    International Nuclear Information System (INIS)

    Derring, L.R.

    1990-01-01

    To demonstrate compliance with the performance objectives governing protection of the general population in 10 CFR 61.41, applicants for land disposal of low-level radioactive waste are required to conduct a pathways analysis, or quantitative evaluation of radionuclide release, transport through environmental media, and dose to man. The Nuclear Regulatory Commission staff defined a strategy and initiated a project at Sandia National Laboratories to develop a methodology for independently evaluating an applicant's analysis of postclosure performance. This performance assessment methodology was developed in five stages: identification of environmental pathways, ranking the significance of the pathways, identification and integration of models for pathway analyses, identification and selection of computer codes and techniques for the methodology, and implementation of the codes and documentation of the methodology. This paper summarizes the NRC approach for conducting evaluations of license applications for low-level radioactive waste facilities. 23 refs

  10. Dietary protein level and performance of growing Baladi kids.

    Science.gov (United States)

    Abdelrahman, M M; Aljumaah, R S

    2014-01-01

    A study was conducted to evaluate the effect of feeding different levels of protein to black Baladi breed kids. Weanling Baladi kids (n=18; 75 to 90 days old) were selected and individually housed at our experimental farm. Kids were divided randomly to one of the three treatments for 12 weeks. The three dietary treatments were: T1: control ration, formulated according to NRC to cover the protein (level 1) and other nutrients requirements. T2: ration formulated to cover only 75% of protein (level 2) recommended by NRC. T3: control diet + 2.4 g undegradable methionine (Smartamine®)/day/kid (level 3). Feed intake, initial and monthly body weights were recorded. Blood samples were collected monthly and analyzed for metabolites and Co, Zn and Cu levels. Decreasing the dietary level of protein (T2) negatively affected (Pkids below the NRC requirements of protein negatively affect the growth performance and feed efficiency. The recommended protein level by NRC for growing kids cover the requirements of growing black Baladi kids for maximum growth and productivity.

  11. High-performance n-type organic semiconductors: incorporating specific electron-withdrawing motifs to achieve tight molecular stacking and optimized energy levels.

    Science.gov (United States)

    Yun, Sun Woo; Kim, Jong H; Shin, Seunghoon; Yang, Hoichang; An, Byeong-Kwan; Yang, Lin; Park, Soo Young

    2012-02-14

    Novel π–conjugated cyanostilbene-based semiconductors (Hex-3,5-TFPTA and Hex-4-TFPTA) with tight molecular stacking and optimized energy levels are synthesized. Hex-4-TFPTA exhibits high-performance n-type organic field-effect transistor (OFET) properties with electron mobilities as high as 2.14 cm2 V−1s−1 and on-off current ratios Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. GABA level, gamma oscillation, and working memory performance in schizophrenia

    Directory of Open Access Journals (Sweden)

    Chi-Ming A. Chen

    2014-01-01

    Full Text Available A relationship between working memory impairment, disordered neuronal oscillations, and abnormal prefrontal GABA function has been hypothesized in schizophrenia; however, in vivo GABA measurements and gamma band neural synchrony have not yet been compared in schizophrenia. This case–control pilot study (N = 24 compared baseline and working memory task-induced neuronal oscillations acquired with high-density electroencephalograms (EEGs to GABA levels measured in vivo with magnetic resonance spectroscopy. Working memory performance, baseline GABA level in the left dorsolateral prefrontal cortex (DLPFC, and measures of gamma oscillations from EEGs at baseline and during a working memory task were obtained. A major limitation of this study is a relatively small sample size for several analyses due to the integration of diverse methodologies and participant compliance. Working memory performance was significantly lower for patients than for controls. During the working memory task, patients (n = 7 had significantly lower amplitudes in gamma oscillations than controls (n = 9. However, both at rest and across working memory stages, there were significant correlations between gamma oscillation amplitude and left DLPFC GABA level. Peak gamma frequency during the encoding stage of the working memory task (n = 16 significantly correlated with GABA level and working memory performance. Despite gamma band amplitude deficits in patients across working memory stages, both baseline and working memory-induced gamma oscillations showed strong dependence on baseline GABA levels in patients and controls. These findings suggest a critical role for GABA function in gamma band oscillations, even under conditions of system and cognitive impairments as seen in schizophrenia.

  13. A dulal-functional medium voltage level DVR to limit downstream fault currents

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Li, Yun Wei; Vilathgamuwa, D. Mahinda

    2007-01-01

    on the other parallel feeders connected to PCC. Furthermore, if not controlled properly, the DVR might also contribute to this PCC voltage sag in the process of compensating the missing voltage, thus further worsening the fault situation. To limit the flow of large line currents, and therefore restore the PCC...... situations. Controlling the DVR as a virtual inductor would also ensure zero real power absorption during the DVR compensation and thus minimize the stress in the dc link. Finally, the proposed fault current limiting algorithm has been tested in Matlab/Simulink simulation and experimentally on a medium......The dynamic voltage restorer (DVR) is a modern custom power device used in power distribution networks to protect consumers from sudden sags (and swells) in grid voltage. Implemented at medium voltage level, the DVR can be used to protect a group of medium voltage or low voltage consumers. However...

  14. Directions in low-level radioactive waste management. Low level-radioactive waste disposal: currently operating commercial facilities

    International Nuclear Information System (INIS)

    1983-09-01

    This publication discusses three commercial facilities that receive and dispose of low-level radioactive waste. The facilities are located in Barnwell, South Carolina; Beatty, Nevada; and Richland, Washington. All three facilities initiated operations in the 1960s. The three facilities have operated without such major problems as those which led to the closure of three other commercial disposal facilities located in the United States. The Beatty site could be closed in 1983 as a result of a Nevada Board of Health ruling that renewal of the site license would be inimical to public health and safety. The site remains open pending federal and state court hearings, which began in January 1983, to resolve the Board of Health ruling. The three sites may also be affected by NRC's 10 CFR Part 61 regulations, but the impact of those regulations, issued in December 1982, has not yet been assessed. This document provides detailed information on the history and current status of each facility. This information is intended, primarily, to assist state officials - executive, legislative, and agency - in planning for, establishing, and managing low-level waste disposal facilities. 12 references

  15. A Single Rod Multi-modality Multi-interface Level Sensor Using an AC Current Source

    Directory of Open Access Journals (Sweden)

    Abdulgader Hwili

    2008-05-01

    Full Text Available Crude oil separation is an important process in the oil industry. To make efficient use of the separators, it is important to know their internal behaviour, and to measure the levels of multi-interfaces between different materials, such as gas-foam, foam-oil, oil-emulsion, emulsion-water and water-solids. A single-rod multi-modality multi-interface level sensor is presented, which has a current source, and electromagnetic modalities. Some key issues have been addressed, including the effect of salt content and temperature i.e. conductivity on the measurement.

  16. Current Harmonics from Single-Phase Grid-Connected Inverters

    DEFF Research Database (Denmark)

    Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

    2016-01-01

    Environmental conditions and operational modes may significantly impact the distortion level of the injected current from single-phase grid-connected inverter systems, such as photovoltaic (PV) inverters, which may operate in cloudy days with a maximum power point tracking, in a non-unity power...... factor, or in the low voltage ride through mode with reactive current injection. In this paper, the mechanism of the harmonic current injection from grid-connected single-phase inverter systems is thus explored, and the analysis is conducted on single-phase PV systems. In particular, the analysis...... is focused on the impacts of the power factor and the feed-in grid current level on the quality of the feed-in grid current from single-phase inverters. As a consequence, an internal model principle based high performance current control solution is tailor-made and developed for single-phase grid-connected...

  17. U.S. Coast Guard Officer Performance Management System: An Analysis of Current Commitment Levels and Potential Effectiveness Indicators.

    Science.gov (United States)

    1983-03-01

    knowledge of current PA technology . Aditionally, inzernal change agents maj often find themselves without the support structure necessary to effect...Minmzberg [Ref. 13], MCall (Ref. 14], and Bennis [Ref. 15], to observe and characterize the nature of managerial work have been enlightering . These studies

  18. Current lead thermal analysis code 'CURRENT'

    International Nuclear Information System (INIS)

    Yamaguchi, Masahito; Tada, Eisuke; Shimamoto, Susumu; Hata, Kenichiro.

    1985-08-01

    Large gas-cooled current lead with the capacity more than 30 kA and 22 kV is required for superconducting toroidal and poloidal coils for fusion application. The current lead is used to carry electrical current from the power supply system at room temperature to the superconducting coil at 4 K. Accordingly, the thermal performance of the current lead is significantly important to determine the heat load requirements of the coil system at 4 K. Japan Atomic Energy Research Institute (JAERI) has being developed the large gas-cooled current leads with the optimum condition in which the heat load is around 1 W per 1 kA at 4 K. In order to design the current lead with the optimum thermal performances, JAERI developed thermal analysis code named as ''CURRENT'' which can theoretically calculate the optimum geometric shape and cooling conditions of the current lead. The basic equations and the instruction manual of the analysis code are described in this report. (author)

  19. Theoretical and practical program in the non-destructive testing by eddy currents - the first level

    International Nuclear Information System (INIS)

    Shaaban, H.I.; Addarwish, J.M.A.

    2014-11-01

    The testing using eddy currents is one of the non-destructive tests that use electromagnetic property as a basis for testing procedures, and there are many other ways to use this principle, including Remote Field Testing and the Magnetic Flux Leakage test. Eddy currents are electrical currents moving in a circular path, and took the name eddy of eddies that form when a liquid or gas is moving in a circular path because of objection obstacles to its track. They are generated in the material using a variable magnetic field. Non-destructive testing by eddy currents is a technique used for the detection of defects and interruptions in a material and it is a process that relies on the generation of small eddy currents in the material of the part to be examined, provided that this part is of an electrically conducting material. This technique and its scientific basis are explained in this book. Also the devices used in this technique and how to use these devices in details are explained. The book contains Twelve chapters: Introduction to non destructive testing - Engineering materials and its mechanical characteristics - Electrical and magnetic characteristics of engineering materials - Introduction to testing by eddy currents - Factors affecting eddy currents - Basis of electrical circuits used in eddy currents testing devices - Probes of eddy currents testing - Eddy currents testing devices (Theoretical) - Analysis of the examination results of testing by eddy currents: techniques and applications - Applications of testing by eddy currents - Eddy currents testing devices (Application) - Practical lessons for the first level in testing by eddy currents.

  20. Using a High-Performance Planning Model to Increase Levels of Functional Effectiveness Within Professional Development.

    Science.gov (United States)

    Winter, Peggi

    2016-01-01

    Nursing professional practice models continue to shape how we practice nursing by putting families and members at the heart of everything we do. Faced with enormous challenges around healthcare reform, models create frameworks for practice by unifying, uniting, and guiding our nurses. The Kaiser Permanente Practice model was developed to ensure consistency for nursing practice across the continuum. Four key pillars support this practice model and the work of nursing: quality and safety, leadership, professional development, and research/evidence-based practice. These four pillars form the foundation that makes transformational practice possible and aligns nursing with Kaiser Permanente's mission. The purpose of this article is to discuss the pillar of professional development and the components of the Nursing Professional Development: Scope and Standards of Practice model (American Nurses Association & National Nursing Staff Development Organization, 2010) and place them in a five-level development framework. This process allowed us to identify the current organizational level of practice, prioritize each nursing professional development component, and design an operational strategy to move nursing professional development toward a level of high performance. This process is suggested for nursing professional development specialists.

  1. Brake Performance Analysis of ABS for Eddy Current and Electrohydraulic Hybrid Brake System

    Directory of Open Access Journals (Sweden)

    Ren He

    2013-01-01

    Full Text Available This paper introduces an eddy current and electro-hydraulic hybrid brake system to solve problems such as wear, thermal failure, and slow response of traditional vehicle brake system. Mathematical model was built to calculate the torque of the eddy current brake system and hydraulic brake system and analyze the braking force distribution between two types of brake systems. A fuzzy controller on personal computer based on LabVIEW and Matlab was designed and a set of hardware in the loop system was constructed to validate and analyze the performance of the hybrid brake system. Through lots of experiments on dry and wet asphalt roads, the hybrid brake system achieves perfect performance on the experimental bench, the hybrid system reduces abrasion and temperature of the brake disk, response speed is enhanced obviously, fuzzy controller keeps high utilization coefficient due to the optimal slip ratio regulation, and the total brake time has a smaller decrease than traditional hydraulic brake system.

  2. E AREA LOW LEVEL WASTE FACILITY DOE 435.1 PERFORMANCE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Wilhite, E

    2008-03-31

    This Performance Assessment for the Savannah River Site E-Area Low-Level Waste Facility was prepared to meet requirements of Chapter IV of the Department of Energy Order 435.1-1. The Order specifies that a Performance Assessment should provide reasonable assurance that a low-level waste disposal facility will comply with the performance objectives of the Order. The Order also requires assessments of impacts to water resources and to hypothetical inadvertent intruders for purposes of establishing limits on radionuclides that may be disposed near-surface. According to the Order, calculations of potential doses and releases from the facility should address a 1,000-year period after facility closure. The point of compliance for the performance measures relevant to the all pathways and air pathway performance objective, as well as to the impact on water resources assessment requirement, must correspond to the point of highest projected dose or concentration beyond a 100-m buffer zone surrounding the disposed waste following the assumed end of active institutional controls 100 years after facility closure. During the operational and institutional control periods, the point of compliance for the all pathways and air pathway performance measures is the SRS boundary. However, for the water resources impact assessment, the point of compliance remains the point of highest projected dose or concentration beyond a 100-m buffer zone surrounding the disposed waste during the operational and institutional control periods. For performance measures relevant to radon and inadvertent intruders, the points of compliance are the disposal facility surface for all time periods and the disposal facility after the assumed loss of active institutional controls 100 years after facility closure, respectively. The E-Area Low-Level Waste Facility is located in the central region of the SRS known as the General Separations Area. It is an elbow-shaped, cleared area, which curves to the northwest

  3. Sleep complaints affecting school performance at different educational levels.

    Science.gov (United States)

    Pagel, James F; Kwiatkowski, Carol F

    2010-01-01

    The clear association between reports of sleep disturbance and poor school performance has been documented for sleepy adolescents. This study extends that research to students outside the adolescent age grouping in an associated school setting (98 middle school students, 67 high school students, and 64 college students). Reported restless legs and periodic limb movements are significantly associated with lower GPA's in junior high students. Consistent with previous studies, daytime sleepiness was the sleep variable most likely to negatively affects high school students. Sleep onset and maintenance insomnia were the reported sleep variables significantly correlated with poorer school performance in college students. This study indicates that different sleep disorder variables negatively affect performance at different age and educational levels.

  4. Improving performance in golf: current research and implications from a clinical perspective.

    Science.gov (United States)

    Evans, Kerrie; Tuttle, Neil

    2015-01-01

    Golf, a global sport enjoyed by people of all ages and abilities, involves relatively long periods of low intensity exercise interspersed with short bursts of high intensity activity. To meet the physical demands of full swing shots and the mental and physical demands of putting and walking the course, it is frequently recommended that golfers undertake golf-specific exercise programs. Biomechanics, motor learning, and motor control research has increased the understanding of the physical requirements of the game, and using this knowledge, exercise programs aimed at improving golf performance have been developed. However, while it is generally accepted that an exercise program can improve a golfer's physical measurements and some golf performance variables, translating the findings from research into clinical practice to optimise an individual golfer's performance remains challenging. This paper discusses how biomechanical and motor control research has informed current practice and discusses how emerging sophisticated tools and research designs may better assist golfers improve their performance.

  5. Guidance on the Technology Performance Level (TPL) Assessment Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Jochem [National Renewable Energy Lab. (NREL), Golden, CO (United States); Roberts, Jesse D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Babarit, Aurelien [Ecole Centrale de Nantes (France). Lab. of Research in Hydrodynamics, Energetics and Atmospheric Environment (LHEEA); Costello, Ronan [Wave Venture, Penstraze (United Kingdom); Bull, Diana L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Neilson, Kim [Ramboll, Copenhagen (Denmark); Bittencourt, Claudio [DNV GL, London (United Kingdom); Kennedy, Ben [Wave Venture, Penstraze (United Kingdom); Malins, Robert Joseph [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dykes, Katherine [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This document presents the revised Technology Performance Level (TPL) assessment methodology. There are three parts to this revised methodology 1) the Stakeholder Needs and Assessment Guidance (this document), 2) the Technical Submission form, 3) the TPL scoring spreadsheet. The TPL assessment is designed to give a technology neutral or agnostic assessment of any wave energy converter technology. The focus of the TPL is on the performance of the technology in meeting the customer’s needs. The original TPL is described in [1, 2] and those references also detail the critical differences in the nature of the TPL when compared to the more widely used technology readiness level (TRL). (Wave energy TRL is described in [3]). The revised TPL is particularly intended to be useful to investors and also to assist technology developers to conduct comprehensive assessments in a way that is meaningful and attractive to investors. The revised TPL assessment methodology has been derived through a structured Systems Engineering approach. This was a formal process which involved analyzing customer and stakeholder needs through the discipline of Systems Engineering. The results of the process confirmed the high level of completeness of the original methodology presented in [1] (as used in the Wave Energy Prize judging) and now add a significantly increased level of detail in the assessment and an improved more investment focused structure. The revised TPL also incorporates the feedback of the Wave Energy Prize judges.

  6. Dual-Task Performance: Influence of Frailty, Level of Physical Activity, and Cognition.

    Science.gov (United States)

    Giusti Rossi, Paulo; Pires de Andrade, Larissa; Hotta Ansai, Juliana; Silva Farche, Ana Claudia; Carnaz, Leticia; Dalpubel, Daniela; Ferriolli, Eduardo; Assis Carvalho Vale, Francisco; de Medeiros Takahashi, Anielle Cristhine

    2018-03-08

    Cognition and level of physical activity have been associated with frailty syndrome. The development of tools that assess deficits related to physical and cognitive frailties simultaneously are of common interest. However, little is known about how much these aspects influence the performance of dual-task tests. Our aims were (a) to verify the influence of frailty syndrome and objectively measured physical activity and cognition on the Timed Up and Go (TUG) test and Timed Up and Go associated with dual-task (TUG-DT) performances; and (b) to compare TUG and TUG-DT performances between older adults who develop frailty syndrome. Sixty-four community-dwelling older adults were divided into frail, prefrail, and nonfrail groups, according to frailty phenotype. Assessments included anamnesis, screening of frailty syndrome, cognitive assessment (Addenbrooke's cognitive examination), placement of a triaxial accelerometer to assess level of physical activity, and TUG and TUG-DT (TUG associated with a motor-cognitive task of calling a phone number) performances. After 7 days, the accelerometer was removed. A multiple linear regression was applied to identify which independent variables could explain performances in the TUG and TUG-DT. Subsequently, the analysis of covariance test, adjusted for age, cognition, and level of physical activity covariates, was used to compare test performances. There were no differences in cognition between groups. Significant differences in the level of physical activity were found in the frail group. Compared with the frail group, the nonfrail group required less time and fewer steps to complete the TUG. Regarding the TUG-DT, cognition and age influenced the time spent and number of steps, respectively; however, no differences were found between groups. Frail older adults presented worse performance in the TUG when compared with nonfrail older adults. The dual-task test does not differentiate older adults with frailty syndrome, regardless of

  7. Health system performance at the district level in Indonesia after decentralization

    Directory of Open Access Journals (Sweden)

    Choi Yoonjoung

    2010-03-01

    Full Text Available Abstract Background Assessments over the last two decades have showed an overall low level of performance of the health system in Indonesia with wide variation between districts. The reasons advanced for these low levels of performance include the low level of public funding for health and the lack of discretion for health system managers at the district level. When, in 2001, Indonesia implemented a radical decentralization and significantly increased the central transfer of funds to district governments it was widely expected that the performance of the health system would improve. This paper assesses the extent to which the performance of the health system has improved since decentralization. Methods We measured a set of indicators relevant to assessing changes in performance of the health system between two surveys in three areas: utilization of maternal antenatal and delivery care; immunization coverage; and contraceptive source and use. We also measured respondents' demographic characteristics and their living circumstances. These measurements were made in population-based surveys in 10 districts in 2002-03 and repeated in 2007 in the same 10 districts using the same instruments and sampling methods. Results The dominant providers of maternal and child health in these 10 districts are in the private sector. There was a significant decrease in birth deliveries at home, and a corresponding increase in deliveries in health facilities in 5 of the 10 districts, largely due to increased use of private facilities with little change in the already low use of public facilities. Overall, there was no improvement in vaccination of mothers and their children. Of those using modern contraceptive methods, the majority obtained them from the private sector in all districts. Conclusions There has been little improvement in the performance of the health system since decentralization occurred in 2001 even though there have also been significant increases in

  8. Field-measured drag area is a key correlate of level cycling time trial performance

    Directory of Open Access Journals (Sweden)

    James E. Peterman

    2015-08-01

    Full Text Available Drag area (Ad is a primary factor determining aerodynamic resistance during level cycling and is therefore a key determinant of level time trial performance. However, Ad has traditionally been difficult to measure. Our purpose was to determine the value of adding field-measured Ad as a correlate of level cycling time trial performance. In the field, 19 male cyclists performed a level (22.1 km time trial. Separately, field-determined Ad and rolling resistance were calculated for subjects along with projected frontal area assessed directly (AP and indirectly (Est AP. Also, a graded exercise test was performed to determine $\\dot {V}{O}_{2}$V̇O2 peak, lactate threshold (LT, and economy. $\\dot {V}{O}_{2}$V̇O2 peak ($\\mathrm{l}~\\min ^{-1}$lmin−1 and power at LT were significantly correlated to power measured during the time trial (r = 0.83 and 0.69, respectively but were not significantly correlated to performance time (r = − 0.42 and −0.45. The correlation with performance time improved significantly (p < 0.05 when these variables were normalized to Ad. Of note, Ad alone was better correlated to performance time (r = 0.85, p < 0.001 than any combination of non-normalized physiological measure. The best correlate with performance time was field-measured power output during the time trial normalized to Ad (r = − 0.92. AP only accounted for 54% of the variability in Ad. Accordingly, the correlation to performance time was significantly lower using power normalized to AP (r = − 0.75 or Est AP (r = − 0.71. In conclusion, unless normalized to Ad, level time trial performance in the field was not highly correlated to common laboratory measures. Furthermore, our field-measured Ad is easy to determine and was the single best predictor of level time trial performance.

  9. Looking Under the Streetlight? A Framework for Differentiating Performance Measures by Level of Care in a Value-Based Payment Environment.

    Science.gov (United States)

    Naessens, James M; Van Such, Monica B; Nesse, Robert E; Dilling, James A; Swensen, Stephen J; Thompson, Kristine M; Orlowski, Janis M; Santrach, Paula J

    2017-07-01

    The majority of quality measures used to assess providers and hospitals are based on easily obtained data, focused on a few dimensions of quality, and developed mainly for primary/community care and population health. While this approach supports efforts focused on addressing the triple aim of health care, many current quality report cards and assessments do not reflect the breadth or complexity of many referral center practices.In this article, the authors highlight the differences between population health efforts and referral care and address issues related to value measurement and performance assessment. They discuss why measures may need to differ across the three levels of care (primary/community care, secondary care, complex care) and illustrate the need for further risk adjustment to eliminate referral bias.With continued movement toward value-based purchasing, performance measures and reimbursement schemes need to reflect the increased level of intensity required to provide complex care. The authors propose a framework to operationalize value measurement and payment for specialty care, and they make specific recommendations to improve performance measurement for complex patients. Implementing such a framework to differentiate performance measures by level of care involves coordinated efforts to change both policy and operational platforms. An essential component of this framework is a new model that defines the characteristics of patients who require complex care and standardizes metrics that incorporate those definitions.

  10. Somatotype, Level of Competition, and Performance in Attack in Elite Male Volleyball

    Science.gov (United States)

    Giannopoulos, Nikiforos; Vagenas, George; Noutsos, Konstantinos; Barzouka, Karolina; Bergeles, Nikolaos

    2017-01-01

    Abstract This study investigated the relationship between somatotype, level of competition, and performance in attack in elite level male volleyball players. The objective was to test for the potential covariation of competition level (Division A1 vs. A2) and playing position (hitters vs. centers vs. opposites) considering performance in attack. Anthropometric, body composition and somatotype variables were measured according to the Heath-Carter method. The attack actions of 144 players from 48 volleyball matches were analyzed and their performance was rated using a 5-point numerical scale. Results showed that players of Division A1 were taller, heavier, more muscular, and less endomorphic compared to those of Division A2. MANOVA and follow-up discriminant function analysis revealed somatotype differences among playing positions with centers and opposites being endomorph-ectomorph and hitters being central. Centers performed constantly better than hitters and opposites regardless of the division and somatotype. Multiple linear regression analysis showed that variables defining ectomorph and endomorph players, centers, and players of Division A1 significantly determined the relative performance superiority and were able to explain the variation in performance by almost 25%. These results could be taken into account by coaches when assigning players to particular playing positions or when designing individualized position-specific training programs. PMID:28828084

  11. Somatotype, Level of Competition, and Performance in Attack in Elite Male Volleyball

    Directory of Open Access Journals (Sweden)

    Giannopoulos Nikiforos

    2017-08-01

    Full Text Available This study investigated the relationship between somatotype, level of competition, and performance in attack in elite level male volleyball players. The objective was to test for the potential covariation of competition level (Division A1 vs. A2 and playing position (hitters vs. centers vs. opposites considering performance in attack. Anthropometric, body composition and somatotype variables were measured according to the Heath-Carter method. The attack actions of 144 players from 48 volleyball matches were analyzed and their performance was rated using a 5-point numerical scale. Results showed that players of Division A1 were taller, heavier, more muscular, and less endomorphic compared to those of Division A2. MANOVA and follow-up discriminant function analysis revealed somatotype differences among playing positions with centers and opposites being endomorph-ectomorph and hitters being central. Centers performed constantly better than hitters and opposites regardless of the division and somatotype. Multiple linear regression analysis showed that variables defining ectomorph and endomorph players, centers, and players of Division A1 significantly determined the relative performance superiority and were able to explain the variation in performance by almost 25%. These results could be taken into account by coaches when assigning players to particular playing positions or when designing individualized position-specific training programs.

  12. Optimization of L-shaped tunneling field-effect transistor for ambipolar current suppression and Analog/RF performance enhancement

    Science.gov (United States)

    Li, Cong; Zhao, Xiaolong; Zhuang, Yiqi; Yan, Zhirui; Guo, Jiaming; Han, Ru

    2018-03-01

    L-shaped tunneling field-effect transistor (LTFET) has larger tunnel area than planar TFET, which leads to enhanced on-current ION . However, LTFET suffers from severe ambipolar behavior, which needs to be further optimized for low power and high-frequency applications. In this paper, both hetero-gate-dielectric (HGD) and lightly doped drain (LDD) structures are introduced into LTFET for suppression of ambipolarity and improvement of analog/RF performance of LTFET. Current-voltage characteristics, the variation of energy band diagrams, distribution of band-to-band tunneling (BTBT) generation and distribution of electric field are analyzed for our proposed HGD-LDD-LTFET. In addition, the effect of LDD on the ambipolar behavior of LTFET is investigated, the length and doping concentration of LDD is also optimized for better suppression of ambipolar current. Finally, analog/RF performance of HGD-LDD-LTFET are studied in terms of gate-source capacitance, gate-drain capacitance, cut-off frequency, and gain bandwidth production. TCAD simulation results show that HGD-LDD-LTFET not only drastically suppresses ambipolar current but also improves analog/RF performance compared with conventional LTFET.

  13. High-Level Performance Modeling of SAR Systems

    Science.gov (United States)

    Chen, Curtis

    2006-01-01

    SAUSAGE (Still Another Utility for SAR Analysis that s General and Extensible) is a computer program for modeling (see figure) the performance of synthetic- aperture radar (SAR) or interferometric synthetic-aperture radar (InSAR or IFSAR) systems. The user is assumed to be familiar with the basic principles of SAR imaging and interferometry. Given design parameters (e.g., altitude, power, and bandwidth) that characterize a radar system, the software predicts various performance metrics (e.g., signal-to-noise ratio and resolution). SAUSAGE is intended to be a general software tool for quick, high-level evaluation of radar designs; it is not meant to capture all the subtleties, nuances, and particulars of specific systems. SAUSAGE was written to facilitate the exploration of engineering tradeoffs within the multidimensional space of design parameters. Typically, this space is examined through an iterative process of adjusting the values of the design parameters and examining the effects of the adjustments on the overall performance of the system at each iteration. The software is designed to be modular and extensible to enable consideration of a variety of operating modes and antenna beam patterns, including, for example, strip-map and spotlight SAR acquisitions, polarimetry, burst modes, and squinted geometries.

  14. Effect Of Dietary Protein Levels On The Performance And Carcass ...

    African Journals Online (AJOL)

    Effect Of Dietary Protein Levels On The Performance And Carcass ... Nigerian Journal of Animal Production ... Response criteria such as weight gain and feed conversion ratio, among others, and carcass characteristics were measured.

  15. Performance-Enhanced Activated Carbon Electrodes for Supercapacitors Combining Both Graphene-Modified Current Collectors and Graphene Conductive Additive

    Science.gov (United States)

    Wang, Rubing; Qian, Yuting; Li, Weiwei; Zhu, Shoupu; Liu, Fengkui; Guo, Yufen; Chen, Mingliang; Li, Qi; Liu, Liwei

    2018-01-01

    Graphene has been widely used in the active material, conductive agent, binder or current collector for supercapacitors, due to its large specific surface area, high conductivity, and electron mobility. However, works simultaneously employing graphene as conductive agent and current collector were rarely reported. Here, we report improved activated carbon (AC) electrodes (AC@G@NiF/G) simultaneously combining chemical vapor deposition (CVD) graphene-modified nickel foams (NiF/Gs) current collectors and high quality few-layer graphene conductive additive instead of carbon black (CB). The synergistic effect of NiF/Gs and graphene additive makes the performances of AC@G@NiF/G electrodes superior to those of electrodes with CB or with nickel foam current collectors. The performances of AC@G@NiF/G electrodes show that for the few-layer graphene addition exists an optimum value around 5 wt %, rather than a larger addition of graphene, works out better. A symmetric supercapacitor assembled by AC@G@NiF/G electrodes exhibits excellent cycling stability. We attribute improved performances to graphene-enhanced conductivity of electrode materials and NiF/Gs with 3D graphene conductive network and lower oxidation, largely improving the electrical contact between active materials and current collectors. PMID:29762528

  16. Performance-Enhanced Activated Carbon Electrodes for Supercapacitors Combining Both Graphene-Modified Current Collectors and Graphene Conductive Additive.

    Science.gov (United States)

    Wang, Rubing; Qian, Yuting; Li, Weiwei; Zhu, Shoupu; Liu, Fengkui; Guo, Yufen; Chen, Mingliang; Li, Qi; Liu, Liwei

    2018-05-15

    Graphene has been widely used in the active material, conductive agent, binder or current collector for supercapacitors, due to its large specific surface area, high conductivity, and electron mobility. However, works simultaneously employing graphene as conductive agent and current collector were rarely reported. Here, we report improved activated carbon (AC) electrodes (AC@G@NiF/G) simultaneously combining chemical vapor deposition (CVD) graphene-modified nickel foams (NiF/Gs) current collectors and high quality few-layer graphene conductive additive instead of carbon black (CB). The synergistic effect of NiF/Gs and graphene additive makes the performances of AC@G@NiF/G electrodes superior to those of electrodes with CB or with nickel foam current collectors. The performances of AC@G@NiF/G electrodes show that for the few-layer graphene addition exists an optimum value around 5 wt %, rather than a larger addition of graphene, works out better. A symmetric supercapacitor assembled by AC@G@NiF/G electrodes exhibits excellent cycling stability. We attribute improved performances to graphene-enhanced conductivity of electrode materials and NiF/Gs with 3D graphene conductive network and lower oxidation, largely improving the electrical contact between active materials and current collectors.

  17. Performance evaluation of wideband bio-impedance spectroscopy using constant voltage source and constant current source

    International Nuclear Information System (INIS)

    Mohamadou, Youssoufa; Oh, Tong In; Wi, Hun; Sohal, Harsh; Farooq, Adnan; Woo, Eung Je; McEwan, Alistair Lee

    2012-01-01

    Current sources are widely used in bio-impedance spectroscopy (BIS) measurement systems to maximize current injection for increased signal to noise while keeping within medical safety specifications. High-performance current sources based on the Howland current pump with optimized impedance converters are able to minimize stray capacitance of the cables and setup. This approach is limited at high frequencies primarily due to the deteriorated output impedance of the constant current source when situated in a real measurement system. For this reason, voltage sources have been suggested, but they require a current sensing resistor, and the SNR reduces at low impedance loads due to the lower current required to maintain constant voltage. In this paper, we compare the performance of a current source-based BIS and a voltage source-based BIS, which use common components. The current source BIS is based on a Howland current pump and generalized impedance converters to maintain a high output impedance of more than 1 MΩ at 2 MHz. The voltage source BIS is based on voltage division between an internal current sensing resistor (R s ) and an external sample. To maintain high SNR, R s is varied so that the source voltage is divided more or less equally. In order to calibrate the systems, we measured the transfer function of the BIS systems with several known resistor and capacitor loads. From this we may estimate the resistance and capacitance of biological tissues using the least-squares method to minimize error between the measured transimpedance excluding the system transfer function and that from an impedance model. When tested on realistic loads including discrete resistors and capacitors, and saline and agar phantoms, the voltage source-based BIS system had a wider bandwidth of 10 Hz to 2.2 MHz with less than 1% deviation from the expected spectra compared to more than 10% with the current source. The voltage source also showed an SNR of at least 60 dB up to 2.2 MHz

  18. High-performance supercapacitors using a nanoporous current collector made from super-aligned carbon nanotubes

    Science.gov (United States)

    Zhou, Ruifeng; Meng, Chuizhou; Zhu, Feng; Li, Qunqing; Liu, Changhong; Fan, Shoushan; Jiang, Kaili

    2010-08-01

    Nanoporous current collectors for supercapacitors have been fabricated by cross-stacking super-aligned carbon nanotube (SACNT) films as a replacement for heavy conventional metallic current collectors. The CNT-film current collectors have good conductivity, extremely low density (27 µg cm - 2), high specific surface area, excellent flexibility and good electrochemical stability. Nanosized active materials such as NiO, Co3O4 or Mn2O3 nanoparticles can be directly synthesized on the SACNT films by a straightforward one-step, in situ decomposition strategy that is both efficient and environmentally friendly. These composite films can be integrated into a pseudo-capacitor that does not use metallic current collectors, but nevertheless shows very good performance, including high specific capacitance (~500 F g - 1, including the current collector mass), reliable electrochemical stability (<4.5% degradation in 2500 cycles) and a very high rate capability (245 F g - 1 at 155 A g - 1).

  19. High-performance supercapacitors using a nanoporous current collector made from super-aligned carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Ruifeng; Meng Chuizhou; Zhu Feng; Li Qunqing; Liu Changhong; Fan Shoushan; Jiang Kaili, E-mail: JiangKL@tsinghua.edu.cn [Department of Physics and Tsinghua-Foxconn Nanotechnology Research Center, Tsinghua University, Beijing 100084 (China)

    2010-08-27

    Nanoporous current collectors for supercapacitors have been fabricated by cross-stacking super-aligned carbon nanotube (SACNT) films as a replacement for heavy conventional metallic current collectors. The CNT-film current collectors have good conductivity, extremely low density (27 {mu}g cm{sup -2}), high specific surface area, excellent flexibility and good electrochemical stability. Nanosized active materials such as NiO, Co{sub 3}O{sub 4} or Mn{sub 2}O{sub 3} nanoparticles can be directly synthesized on the SACNT films by a straightforward one-step, in situ decomposition strategy that is both efficient and environmentally friendly. These composite films can be integrated into a pseudo-capacitor that does not use metallic current collectors, but nevertheless shows very good performance, including high specific capacitance ({approx}500 F g{sup -1}, including the current collector mass), reliable electrochemical stability (<4.5% degradation in 2500 cycles) and a very high rate capability (245 F g{sup -1} at 155 A g{sup -1}).

  20. SLEEP COMPLAINTS AFFECTING SCHOOL PERFORMANCE AT DIFFERENT EDUCATIONAL LEVELS

    Directory of Open Access Journals (Sweden)

    James F Pagel

    2010-11-01

    Full Text Available The clear association between reports of sleep disturbance and poor school performance has been documented for sleepy adolescents. This study extends that research to students outside the adolescent age grouping in an associated school setting (98 middle school students, 67 high school students, and 64 college students. Reported restless legs and periodic limb movements are significantly associated with lower GPA’s in junior high students. Consistent with previous studies, daytime sleepiness was the sleep variable most likely to negatively affects high school students. Sleep onset and maintenance insomnia were the reported sleep variables significantly correlated with poorer school performance in college students. This study indicates that different sleep disorder variables negatively affect performance at different age and educational levels.

  1. Personality Characteristics and Level of Performance of Male County Extension Agents in Wisconsin.

    Science.gov (United States)

    Pandya, Dasharathrai Navnitrai

    The major purpose of this study was to determine the relationship between selected personality characteristics and attitudes of male extension agents in Wisconsin, and their level of job performance. The relationships between selected background factors and the level of agent's job performance were also studied. Subjects were 79 male county agents…

  2. Effects of caffeine and anxiety level on psychomotor performance ...

    African Journals Online (AJOL)

    The study investigated the effects of caffeine and anxiety level on psychomotor performance. Sixty-eight (68) volunteer male and female students who were randomly selected from different academic faculties at the University of Lagos participated in this study. Their ages ranged from 18 to 32 years, with body weights ...

  3. Key tasks in healthcare marketing: assessing importance and current level of knowledge.

    Science.gov (United States)

    Kennett, Pamela A; Henson, Steve W; Crow, Stephen M; Hartman, Sandra J

    2005-01-01

    When examining the healthcare industry, the need for continuing education in internal functions (i.e., HR management) has been documented. However, equally important to success in the healthcare industry are external functions such as marketing. In an expansion of research on internally focused functions, we report findings from an exploratory study designed to examine the perceptions of executives about managerial skill needs in the externally focused area of marketing. Specifically, we examine eight key tasks in marketing and ask executives to rate the level of knowledge required for each and then to assess current, or actual, levels of knowledge in the field. Findings suggest that pricing strategy, product strategy, and segmentation and targeting were the tasks that require the most knowledge for healthcare marketers, and that they do, in fact, perceive various gaps in all of the areas examined. Implications and suggestions for future research are provided.

  4. The influence of current collector corrosion on the performance of electrochemical capacitors

    Science.gov (United States)

    Wojciechowski, Jarosław; Kolanowski, Łukasz; Bund, Andreas; Lota, Grzegorz

    2017-11-01

    This paper discusses the effect of current collector (stainless steel 316L) corrosion on the performance of electrochemical capacitors operated in aqueous electrolytes. This topic seems to be often neglected in scientific research. The studied electrolytes were 1 M H2SO4, 1 M KI, 1 M Na2SO4, 1 M KOH and 6 M KOH. The corrosion process was investigated by means of selected direct and alternating current techniques. The surface of the current collectors as well as the corrosion products were characterised using scanning electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy and atomic force microscopy. Stainless steel 316L in alkaline solutions is characterised by the lowest values of corrosion potentials whereas the potentials in acidic media become the most noble. Our studies show that corrosion potentials increase with decreasing pH value. This phenomenon can be explained with the formation of passive oxide films on the stainless steel current collectors. The passive oxide films are usually thicker and more porous in alkaline solutions than that in the other electrolytes. The processes occurring at the electrode/electrolyte interfaces strongly influence the working parameters of electrochemical capacitors such as voltage, working potentials of single electrodes, self-discharge as well as the internal resistance and cycling stability.

  5. Historic and current hepatitis B viral DNA and quantitative HBsAg level are not associated with cirrhosis in non-Asian women with chronic hepatitis B.

    Science.gov (United States)

    Harkisoen, S; Arends, J E; van den Hoek, J A R; Whelan, J; van Erpecum, K J; Boland, G J; Hoepelman, A I M

    2014-12-01

    Some studies done in Asian patients have shown that serum levels of hepatitis B virus (HBV) DNA predict the development of cirrhosis. However, it is unclear whether this also applies for non-Asian patients. This study investigated historic and current HBV DNA and quantitative hepatitis B surface antigen (HBsAg) levels as predictors of cirrhosis in non-Asian women with chronic HBV. A retrospective cohort study of non-Asian women with chronic HBV was performed. Among other variables, HBV DNA and quantitative HBsAg levels were measured in stored historic serum samples obtained during pregnancy (period 1990-2004) and current serum samples (period 2011-2012) to determine any association with liver cirrhosis by liver stiffness measurement (LSM). One hundred and nineteen asymptomatic, treatment-naïve non-Asian women were included; the median number of years between the historic sample and the current sample was 17 (interquartile range (IQR) 13-20). The median historic log HBV DNA and quantitative log HBsAg levels were 2.5 (IQR 1.9-3.4) IU/ml and 4.2 (IQR 3.6-4.5) IU/ml, respectively. LSM diagnosed 14 patients (12%) with F3-F4 fibrosis, i.e. stiffness >8.1kPa. No association of cirrhosis was found with historic HBV DNA (relative risk (RR) 0.34, 95% confidence interval (CI) 0.05-2.44) or with the quantitative HBsAg level (HBsAg level >1000 IU/ml, RR 0.35, 95% CI 0.11-1.11). Multivariable analysis identified alcohol consumption (odds ratio (OR) 6.4, 95% CI 1.3-30.1), aspartate aminotransferase >0.5 times the upper limit of normal (OR 15.4, 95% CI 1.9-122.6), and prothrombin time (OR 12.0, 95% CI 1.2-120.4), but not HBV DNA or quantitative HBsAg level, to be independent predictors of the presence of cirrhosis. Neither historic nor current HBV DNA or the quantitative HBsAg level is associated with the development of HBV-related cirrhosis in non-Asian women. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Selection of a computer code for Hanford low-level waste engineered-system performance assessment

    International Nuclear Information System (INIS)

    McGrail, B.P.; Mahoney, L.A.

    1995-10-01

    Planned performance assessments for the proposed disposal of low-level waste (LLW) glass produced from remediation of wastes stored in underground tanks at Hanford, Washington will require calculations of radionuclide release rates from the subsurface disposal facility. These calculations will be done with the aid of computer codes. Currently available computer codes were ranked in terms of the feature sets implemented in the code that match a set of physical, chemical, numerical, and functional capabilities needed to assess release rates from the engineered system. The needed capabilities were identified from an analysis of the important physical and chemical process expected to affect LLW glass corrosion and the mobility of radionuclides. The highest ranked computer code was found to be the ARES-CT code developed at PNL for the US Department of Energy for evaluation of and land disposal sites

  7. Performance analysis of three-dimensional-triple-level cell and two-dimensional-multi-level cell NAND flash hybrid solid-state drives

    Science.gov (United States)

    Sakaki, Yukiya; Yamada, Tomoaki; Matsui, Chihiro; Yamaga, Yusuke; Takeuchi, Ken

    2018-04-01

    In order to improve performance of solid-state drives (SSDs), hybrid SSDs have been proposed. Hybrid SSDs consist of more than two types of NAND flash memories or NAND flash memories and storage-class memories (SCMs). However, the cost of hybrid SSDs adopting SCMs is more expensive than that of NAND flash only SSDs because of the high bit cost of SCMs. This paper proposes unique hybrid SSDs with two-dimensional (2D) horizontal multi-level cell (MLC)/three-dimensional (3D) vertical triple-level cell (TLC) NAND flash memories to achieve higher cost-performance. The 2D-MLC/3D-TLC hybrid SSD achieves up to 31% higher performance than the conventional 2D-MLC/2D-TLC hybrid SSD. The factors of different performance between the proposed hybrid SSD and the conventional hybrid SSD are analyzed by changing its block size, read/write/erase latencies, and write unit of 3D-TLC NAND flash memory, by means of a transaction-level modeling simulator.

  8. It Is Not Only Mentoring: The Combined Influences of Individual-Level and Team-Level Support on Job Performance

    Science.gov (United States)

    van Emmerik, I. J. Hetty

    2008-01-01

    Purpose: The paper aims to follow social exchange theory and group social capital theory, to predict positive relationships between (informal) mentoring and various support resources for two types of performance (i.e. perceptions of individual and team performance). Design/methodology/approach: The associations of individual-level mentoring and…

  9. Can Production Subsidies Explain China's Export Performance? Evidence from Firm-level Data

    DEFF Research Database (Denmark)

    Gong, Yundan; Yu, Zhihong; Girma, Sourafel

    2009-01-01

    This paper analyses the relationship between production subsidies and firms" export performance using a very comprehensive and recent firm-level database and controlling for the endogeneity of subsidies. It documents robust evidence that production subsidies stimulate export activity at the inten......This paper analyses the relationship between production subsidies and firms" export performance using a very comprehensive and recent firm-level database and controlling for the endogeneity of subsidies. It documents robust evidence that production subsidies stimulate export activity...

  10. Determination of performance criteria for high-level solidified nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Heckman, R.A.; Holdsworth, T.

    1979-05-07

    To minimize radiological risk from the operation of a waste management system, performance limits on volatilization, particulate dispersion, and dissolution characteristics of solidified high level waste must be specified. The results show clearly that the pre-emplacement environs are more limiting in establishing the waste form performance criteria than the post-emplacement environs. Absolute values of expected risk are very sensitive to modeling assumptions. The transportation and interim storage operations appear to be most limiting in determining the performance characteristics required. The expected values of risk do not rely upon the repositories remaining intact over the potentially hazardous lifetime of the waste.

  11. Determination of performance criteria for high-level solidified nuclear waste

    International Nuclear Information System (INIS)

    Heckman, R.A.; Holdsworth, T.

    1979-01-01

    To minimize radiological risk from the operation of a waste management system, performance limits on volatilization, particulate dispersion, and dissolution characteristics of solidified high level waste must be specified. The results show clearly that the pre-emplacement environs are more limiting in establishing the waste form performance criteria than the post-emplacement environs. Absolute values of expected risk are very sensitive to modeling assumptions. The transportation and interim storage operations appear to be most limiting in determining the performance characteristics required. The expected values of risk do not rely upon the repositories remaining intact over the potentially hazardous lifetime of the waste

  12. The performance of broiler finisher birds fed varying levels of feather ...

    African Journals Online (AJOL)

    The performance of broiler finisher birds fed varying levels of feather meal as replacement for soya bean meal. ... meal increased, feed cost/ kg weight gain increased and both differed significantly (P<0.05) between treatment means, while the birds tolerated feather meal up to 7.5% inclusion level, 2.5% was the optimal.

  13. Enterprise Performance in Asia: Using firm-level data for Policy ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Enterprise Performance in Asia: Using firm-level data for Policy-making. Micro and small enterprises play a critical role in job creation and economic ... prevent gender-based violence, and make digital platforms work for inclusive development.

  14. Measurement of health system performance at district level: A study protocol

    Directory of Open Access Journals (Sweden)

    Atul Sharma

    2018-01-01

    Full Text Available Background: Limited efforts have been observed in low and middle income countries to undertake health system performance assessment at district level. Absence of a comprehensive data collection tool and lack of a standardised single summary measure defining overall performance are some of the main problems. Present study has been undertaken to develop a summary composite health system performance index at district level. Methods: A broad range of indicators covering all six domains as per building block framework were finalized by an expert panel. The domains were classified into twenty sub-domains, with 70 input and process indicators to measure performance. Seven sub-domains for assessing health system outputs and outcomes were identified, with a total of 28 indicators. Districts in Haryana state from north India were selected for the study. Primary and secondary data will be collected from 378 health facilities, district and state health directorate headquarters. Indicators will be normalized, aggregated to generate composite performance index at district level. Domain specific scores will present the quality of individual building block domains in the public health system. Robustness of the results will be checked using sensitivity analysis. Expected impact for public health: The study presents a methodology for comprehensive assessment of all health system domains on basis of input, process, output and outcome indicators which has never been reported from India. Generation of this index will help identify policy and implementation areas of concern and point towards potential solutions. Results may also help understand relationships between individual building blocks and their sub-components.

  15. Performance of a Two-Level Call Admission Control Scheme for DS-CDMA Wireless Networks

    Directory of Open Access Journals (Sweden)

    Fapojuwo Abraham O

    2007-01-01

    Full Text Available We propose a two-level call admission control (CAC scheme for direct sequence code division multiple access (DS-CDMA wireless networks supporting multimedia traffic and evaluate its performance. The first-level admission control assigns higher priority to real-time calls (also referred to as class 0 calls in gaining access to the system resources. The second level admits nonreal-time calls (or class 1 calls based on the resources remaining after meeting the resource needs for real-time calls. However, to ensure some minimum level of performance for nonreal-time calls, the scheme reserves some resources for such calls. The proposed two-level CAC scheme utilizes the delay-tolerant characteristic of non-real-time calls by incorporating a queue to temporarily store those that cannot be assigned resources at the time of initial access. We analyze and evaluate the call blocking, outage probability, throughput, and average queuing delay performance of the proposed two-level CAC scheme using Markov chain theory. The analytic results are validated by simulation results. The numerical results show that the proposed two-level CAC scheme provides better performance than the single-level CAC scheme. Based on these results, it is concluded that the proposed two-level CAC scheme serves as a good solution for supporting multimedia applications in DS-CDMA wireless communication systems.

  16. Performance of a Two-Level Call Admission Control Scheme for DS-CDMA Wireless Networks

    Directory of Open Access Journals (Sweden)

    Abraham O. Fapojuwo

    2007-11-01

    Full Text Available We propose a two-level call admission control (CAC scheme for direct sequence code division multiple access (DS-CDMA wireless networks supporting multimedia traffic and evaluate its performance. The first-level admission control assigns higher priority to real-time calls (also referred to as class 0 calls in gaining access to the system resources. The second level admits nonreal-time calls (or class 1 calls based on the resources remaining after meeting the resource needs for real-time calls. However, to ensure some minimum level of performance for nonreal-time calls, the scheme reserves some resources for such calls. The proposed two-level CAC scheme utilizes the delay-tolerant characteristic of non-real-time calls by incorporating a queue to temporarily store those that cannot be assigned resources at the time of initial access. We analyze and evaluate the call blocking, outage probability, throughput, and average queuing delay performance of the proposed two-level CAC scheme using Markov chain theory. The analytic results are validated by simulation results. The numerical results show that the proposed two-level CAC scheme provides better performance than the single-level CAC scheme. Based on these results, it is concluded that the proposed two-level CAC scheme serves as a good solution for supporting multimedia applications in DS-CDMA wireless communication systems.

  17. Hydrological performance assessment on siting the high level radioactive waste repository

    International Nuclear Information System (INIS)

    Guo Yonghai; Liu Shufen; Wang Ju; Wang Zhiming; Su Rui; Lv Chuanhe; Zong Zihua

    2007-01-01

    Based on the research experiences in China and some developed countries in the world, the processes and methods on hydrological performance assessment for the siting of high radioactive repository are discussed in this paper. The methods and contents of hydrological performance assessment are discussed respectively for region, area and site hydrological investigation stages. At the same time, the hydrological performance assessment of the potential site for high level radioactive waste in China is introduced. (authors)

  18. Measurement technology of RF interference current in high current system

    Science.gov (United States)

    Zhao, Zhihua; Li, Jianxuan; Zhang, Xiangming; Zhang, Lei

    2018-06-01

    Current probe is a detection method commonly used in electromagnetic compatibility. With the development of power electronics technology, the power level of power conversion devices is constantly increasing, and the power current of the electric energy conversion device in the electromagnetic launch system can reach 10kA. Current probe conventionally used in EMC (electromagnetic compatibility) detection cannot meet the test requirements on high current system due to the magnetic saturation problem. The conventional high current sensor is also not suitable for the RF (Radio Frequency) interference current measurement in high current power device due to the high noise level in the output of active amplifier. In this paper, a passive flexible current probe based on Rogowski coil and matching resistance is proposed that can withstand high current and has low noise level, to solve the measurement problems of interference current in high current power converter. And both differential mode and common mode current detection can be easily carried out with the proposed probe because of the probe's flexible structure.

  19. Five-Phase Five-Level Open-Winding/Star-Winding Inverter Drive for Low-Voltage/High-Current Applications

    DEFF Research Database (Denmark)

    Padmanaban, Sanjeevi Kumar; Blaabjerg, Frede; Wheeler, Patrick

    2016-01-01

    This paper work proposed a five-phase five-level open-/star-winding multilevel AC converter suitable for low-voltage/high-current applications. Modular converter consists of classical two-level five-phase voltage source inverter (VSI) with slight reconfiguration to serve as a multilevel converter...... for open-/star-winding loads. Elaborately, per phase of the VSI is built with one additional bi-directional switch (MOSFET/IGBT) and all five legs links to the neutral through two capacitors. The structure allows multilevel generation to five-level output with greater potential for fault tolerability under...

  20. Brain volumes and neuropsychological performance are related to current smoking and alcoholism history

    Directory of Open Access Journals (Sweden)

    Luhar RB

    2013-11-01

    Full Text Available Riya B Luhar,1,2 Kayle S Sawyer,1,2 Zoe Gravitz,1,2 Susan Mosher Ruiz,1,2 Marlene Oscar-Berman1–3 1US Department of Veterans Affairs, Boston Healthcare System, 2Boston University School of Medicine, 3Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA Background: Dual dependence on alcohol and nicotine is common, with many reports suggesting that more than 80% of alcoholics also smoke cigarettes. Even after cessation of alcohol consumption, many recovering alcoholics continue to smoke. In this exploratory study, we examined how current smoking and a history of alcoholism interacted in relation to brain volumes and neuropsychological performance. Methods: Participants were 14 abstinent long-term alcoholics (seven current smokers and seven nonsmokers, and 13 nonalcoholics (six current smokers and seven nonsmokers. The groups were equivalent in age, gender, education, and intelligence quotient. Two multiecho magnetization-prepared rapid acquisition with gradient echo (MP-RAGE scans were collected for all participants using a 3T magnetic resonance imaging scanner with a 32 channel head coil. Brain volumes for each gray and white matter region of interest were derived using FreeSurfer. Participants completed a battery of neuropsychological tests measuring intelligence quotient, memory, executive functions, personality variables, and affect. Results: Compared to nonsmoking nonalcoholics, alcoholics who smoke (the comorbid group had volumetric abnormalities in: pre- and para-central frontal cortical areas and rostral middle frontal white matter; parahippocampal and temporal pole regions; the amygdala; the pallidum; the ventral diencephalic region; and the lateral ventricle. The comorbid group performed worse than nonsmoking nonalcoholics on tests of executive functioning and on visually-based memory tests. History of alcoholism was associated with higher neuroticism scores among smokers, and current

  1. Tunneling Current Probe for Noncontract Wafer-Level Photodiode Array Testing

    National Research Council Canada - National Science Library

    Verdun, Horacio

    1999-01-01

    The Tunneling Current Probe (TCP) is an automated picometer-sensitive proximity sensor and current measurement system which measures the current through a photodiode detector array element by establishing a tunneling current...

  2. Reliability analysis of component-level redundant topologies for solid-state fault current limiter

    Science.gov (United States)

    Farhadi, Masoud; Abapour, Mehdi; Mohammadi-Ivatloo, Behnam

    2018-04-01

    Experience shows that semiconductor switches in power electronics systems are the most vulnerable components. One of the most common ways to solve this reliability challenge is component-level redundant design. There are four possible configurations for the redundant design in component level. This article presents a comparative reliability analysis between different component-level redundant designs for solid-state fault current limiter. The aim of the proposed analysis is to determine the more reliable component-level redundant configuration. The mean time to failure (MTTF) is used as the reliability parameter. Considering both fault types (open circuit and short circuit), the MTTFs of different configurations are calculated. It is demonstrated that more reliable configuration depends on the junction temperature of the semiconductor switches in the steady state. That junction temperature is a function of (i) ambient temperature, (ii) power loss of the semiconductor switch and (iii) thermal resistance of heat sink. Also, results' sensitivity to each parameter is investigated. The results show that in different conditions, various configurations have higher reliability. The experimental results are presented to clarify the theory and feasibility of the proposed approaches. At last, levelised costs of different configurations are analysed for a fair comparison.

  3. Development and performance test results of 50 kA vapor-cooled current lead for ITER

    International Nuclear Information System (INIS)

    Sugimoto, Makoto; Isono, Takaaki; Hamada, Kazuya

    1998-01-01

    JAERI has developed 50 kA current leads for the International Thermonuclear Experimental Reactor (ITER). The Center Solenoid (CS) Model Coil program is under way by means of international collaboration in ITER-EDA. The CS model coil is being developed for ITER CS coil and is for demonstration for ITER construction. The performance test of the CS model coil will be carried out at the JAERI ITER common test facility (CTF). The current lead consists of the vertical lead and the connection lead. The vertical lead is a vapor-cooled type and has a cable-in-conduit geometry. The vertical lead was designed with a heat leak of 1.2 W/kA at a helium flow rate of 0.06 g/(s·kA). The measured heat leak satisfied the designed value. The connection lead was made from copper pipe soldered with NbTi superconducting wires. The pipe was stabilized by the superconducting wires and a cooling channel. The current lead was operated up to 60 kA. The design and the performance test results of 50 kA current leads are reported. The results meet the specifications for the CS model coil test and for the ITER real machine. (author)

  4. Childhood conditions and current physical performance among non-institutionalized individuals aged 50+ in Israel.

    Science.gov (United States)

    Weinstein, Galit

    2016-12-01

    Adverse socioeconomic conditions in childhood have been previously linked with high risk of various health conditions. However, the association with future physical function has been less studied. Hand grip strength and chair-rising time are objective measures of physical capability indicating current and future health outcomes. The aim of this study was to test the hypothesis that perceived socio-economic status in childhood is related to current measures of physical function, among Israeli participants of the Survey of Health, Ageing and Retirement in Europe project. The study included 2300 participants aged 50 years or older (mean age 68 ± 10; 56 % women). Generalized linear regression models were used to examine the associations of childhood wealth and number of books in residence with grip strength and time to complete five rises from a chair. Logistic regression models were used to assess the relationships between the early life conditions and the ability to perform the physical tests. Adjustment was made for current income or household wealth, and for demographic, anthropometric, health, and life-style measures. Being wealthy and having a large number of books at home in childhood was associated with a stronger hand grip and a better chair-rise test performance. These associations were more robust in women compared to men, and persisted after adjustment for potential covariates. In addition, childhood wealth and number of books were associated with lower risk of being unable to perform the tests. Thus, early-life programming may contribute to physical function indicators in mid- and late-life.

  5. Performance Evaluation of Three-Level Z-Source Inverters Under Semiconductor-Failure Conditions

    DEFF Research Database (Denmark)

    Gao, Feng; Loh, Poh Chiang; Blaabjerg, Frede

    2009-01-01

    This paper evaluates and proposes various compensation methods for three-level Z-source inverters under semiconductor-failure conditions. Unlike the fault-tolerant techniques used in traditional three-level inverters, where either an extra phase-leg or collective switching states are used......, the proposed methods for three-level Z-source inverters simply reconfigure their relevant gating signals so as to ride-through the failed semiconductor conditions smoothly without any significant decrease in their ac-output quality and amplitude. These features are partly attributed to the inherent boost...... under semiconductor-failure conditions. For verifying these described performance features, PLECS simulation and experimental testing were performed with some results captured and shown in a later section for visual confirmation....

  6. Input-parallel output-parallel (IPOP) three-level (TL) DC/DC converters with minimized capacitor ripple currents

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Zhang, Qi

    2016-01-01

    , the component current stresses in the proposed converters are reduced. More significantly, the combination of the proposed IPOP TL circuit structure and the interleaving control strategy can largely reduce the ripple currents on the two input capacitors not only by doubling the frequencies of the ripple...... currents on two input capacitors but also by counteracting part of these ripple currents according to the operation principle of the proposed converters. Therefore, the proposed IPOP TL DC/DC converters with the interleaving control strategy can improve the performances of the converters in increasing...... the lifetimes of the input capacitors and minimizing the sizes of the input capacitors. Finally, the simulation and experimental results are presented to verify the effectiveness and feasibility of the proposed converters combined with the interleaving control strategy....

  7. 20 CFR 666.120 - What are the procedures for negotiating annual levels of performance?

    Science.gov (United States)

    2010-04-01

    ... performance for each core indicator and the customer satisfaction indicators. In negotiating these levels, the... customer satisfaction; (3) The extent to which the levels of performance promote continuous improvement and... other States, taking into account factors including differences in economic conditions, participant...

  8. Job crafting at the team and individual level: Implications for work engagement and performance

    NARCIS (Netherlands)

    Tims, M.; Bakker, A.B.; Derks, D.; Rhenen, van W.

    2013-01-01

    Previous research suggests that employee job crafting is positively related to job performance through employee work engagement. The present study expands this individual-level perspective to the team level by hypothesizing that team job crafting relates positively to team performance through team

  9. A Wide-Range Tunable Level-Keeper Using Vertical Metal-Oxide-Semiconductor Field-Effect Transistors for Current-Reuse Systems

    Science.gov (United States)

    Tanoi, Satoru; Endoh, Tetsuo

    2012-04-01

    A wide-range tunable level-keeper using vertical metal-oxide-semiconductor field-effect transistors (MOSFETs) is proposed for current-reuse analog systems. The design keys for widening tunable range of the operation are a two-path feed-back and a vertical MOSFET with back-bias-effect free. The proposed circuit with the vertical MOSFETs shows the 1.23-V tunable-range of the input level with the 2.4-V internal-supply voltage (VDD) in the simulation. This tunable-range of the proposed circuit is 4.7 times wider than that of the conventional. The achieved current efficiency of the proposed level-keeper is 66% at the 1.2-V output with the 2.4-V VDD. This efficiency of the proposed circuit is twice higher than that of the traditional voltage down converter.

  10. Conscientiousness, openness to experience and extraversion as predictors of nursing work performance: a facet-level analysis.

    Science.gov (United States)

    Ellershaw, Julia; Fullarton, Christie; Rodwell, John; Mcwilliams, John

    2016-03-01

    This study examined the relationships between the personality traits of conscientiousness, openness and extraversion at trait and facet-levels and three indicators of work role performance; proficiency, 'adaptivity' and proactivity measured at individual, team and organisational levels. This is one of the first studies to explore the relationship between personality, measured at trait and facet-level and performance using a comprehensive range of performance indicators. An online survey of 393 nurses from health-care organisations across Australia was conducted to test hypothesised relationships. Path analyses revealed numerous relationships between personality, measured at both trait and facet-levels, and work role performance. Conscientiousness was highlighted as the strongest driver of work role performance across all the indicators, with extraversion also strongly associated with work role performance. Openness to experience, previously considered a week predictor of performance, was, when examined at the facet-level, related to all of the work role performance indicators. Results suggests a bandwidth effect, where the personality traits drive global performance while the facets drive specific performance. Better understanding of the relationship between personality and work role performance will help nurse managers to foster the fit between individual and organisation, improving job satisfaction, engagement, retention and performance in role. © 2015 John Wiley & Sons Ltd.

  11. Agronomic performances of three vetch species growing under different drought levels

    Directory of Open Access Journals (Sweden)

    Sywar Haffani

    2014-09-01

    Full Text Available The current challenge of agriculture is to get the best yields while overcoming frequent water deficit conditions. The objective of this study was to compare performances of three vetch species (Vicia narbonensis L., V. sativa L., and V. villosa Roth subjected to water stress. Plants were sown in pots under rainout shelter and submitted to four water regimes: control (100% field capacity [FC], 80%, 60%, and 40% FC through 3 yr experiment. Results showed that V. narbonensis had the smallest declines in all the studied variables in response to water restriction but the highest water use efficiency (WUE and stress tolerance index (STI in both control and water-treated plants. This indicates the greater tolerance of this species to water constraint and its better water use. Vicia villosa was characterized by drastic declines in leaf area and DM yield (75% and 64%, respectively. It had also the smallest WUE and STI suggesting its low adaptation to water stress. Vicia sativa showed severe reductions in seed yield and yield components; accordingly, it was the most sensitive species in terms of seed yield. The three species implied avoidance strategies to cope with water stress. The different levels of drought tolerance explain the species ecological distribution in Tunisia.

  12. Can Public Managers Make Their Welfare Organizations Adapt to the New Performance Landscape Shaped by the Current Austerity?

    DEFF Research Database (Denmark)

    Pedersen, John Storm; Aagaard, Peter

    2014-01-01

    How managers try to adapt their organizations to the new performance landscape shaped by the current austerity by new forms of change management in Denmark, in the public sector of citizens with disabilities and socially disadvantaged people.......How managers try to adapt their organizations to the new performance landscape shaped by the current austerity by new forms of change management in Denmark, in the public sector of citizens with disabilities and socially disadvantaged people....

  13. Importance of Performance Measurement and MCH Epidemiology Leadership to Quality Improvement Initiatives at the National, State and Local Levels.

    Science.gov (United States)

    Rankin, Kristin M; Gavin, Loretta; Moran, John W; Kroelinger, Charlan D; Vladutiu, Catherine J; Goodman, David A; Sappenfield, William M

    2016-11-01

    Purpose In recognition of the importance of performance measurement and MCH epidemiology leadership to quality improvement (QI) efforts, a plenary session dedicated to this topic was presented at the 2014 CityMatCH Leadership and MCH Epidemiology Conference. This paper summarizes the session and provides two applications of performance measurement to QI in MCH. Description Performance measures addressing processes of care are ubiquitous in the current health system landscape and the MCH community is increasingly applying QI processes, such as Plan-Do-Study-Act (PDSA) cycles, to improve the effectiveness and efficiency of systems impacting MCH populations. QI is maximally effective when well-defined performance measures are used to monitor change. Assessment MCH epidemiologists provide leadership to QI initiatives by identifying population-based outcomes that would benefit from QI, defining and implementing performance measures, assessing and improving data quality and timeliness, reporting variability in measures throughout PDSA cycles, evaluating QI initiative impact, and translating findings to stakeholders. MCH epidemiologists can also ensure that QI initiatives are aligned with MCH priorities at the local, state and federal levels. Two examples of this work, one highlighting use of a contraceptive service performance measure and another describing QI for peripartum hemorrhage prevention, demonstrate MCH epidemiologists' contributions throughout. Challenges remain in applying QI to complex community and systems-level interventions, including those aimed at improving access to quality care. Conclusion MCH epidemiologists provide leadership to QI initiatives by ensuring they are data-informed and supportive of a common MCH agenda, thereby optimizing the potential to improve MCH outcomes.

  14. Evaluation of low level laser and interferential current in the therapy of complex regional pain syndrome by infrared thermographic camera

    Directory of Open Access Journals (Sweden)

    Kocić Mirjana

    2010-01-01

    Full Text Available Background/Aim. Complex regional pain syndrome type I (CRPS I is characterized by continuous regional pain, disproportional according to duration and intensity and to the sort of trauma or other lesion it was caused by. The aim of the study was to evaluate and compare, by using thermovison, the effects of low level laser therapy and therapy with interferential current in treatment of CRPS I. Methods. The prospective randomized controlled clinical study included 45 patients with unilateral CRPS I, after a fracture of the distal end of the radius, of the tibia and/or the fibula, treated in the Clinical Centre in Nis from 2004 to 2007. The group A consisted of 20 patients treated by low level laser therapy and kinesy-therapy, while the patients in the group B (n = 25 were treated by interferential current and kinesy-therapy. The regions of interest were filmed by a thermovision camera on both sides, before and after the 20 therapeutic procedures had been applied. Afterwards, the quantitative analysis and the comparing of thermograms taken before and after the applied therapy were performed. Results. There was statistically significant decrease of the mean maximum temperature difference between the injured and the contralateral extremity after the therapy in comparison to the status before the therapy, with the patients of the group A (p < 0.001 as well as those of the group B (p < 0.001. The decrease was statistically significantly higher in the group A than in the group B (p < 0.05. Conclusions. By the use of the infrared thermovision we showed that in the treatment of CRPS I both physical medicine methods were effective, but the effectiveness of laser therapy was statistically significantly higher compared to that of the interferential current therapy.

  15. Performance assessment for future low-level waste disposal facilities at ORNL

    International Nuclear Information System (INIS)

    Lee, D.W.; Kocher, D.C.

    1989-01-01

    This paper discusses the strategy for waste management on the Oak Ridge Reservation (ORR) and the approach to preparing future performance assessments that has evolved from previous performance assessment studies of low-level radioactive waste disposal on the ORR. The strategy for waste management is based on the concept that waste classification should be determined by performance assessment other than the sources of waste. This dose-based strategy for waste classification and management places special importance on the preparation and interpretation of waste disposal performance assessments for selecting appropriate disposal technologies and developing waste acceptance criteria. Additionally, the challenges to be overcome in the preparation of performance assessments are discussed. 7 refs

  16. New analysis and performance of a wall-current monitor

    Energy Technology Data Exchange (ETDEWEB)

    Suwada, T.; Urano, T.; Kobayashi, H. [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan); Tamiya, K.; Asami, A. [Naruto University of Education, Takashima, Naruto-cho, Naruto-shi 772 (Japan)

    1997-09-01

    A new wall-current monitor has been developed in order to reinforce the beam-monitoring system in the PF 2.5-GeV linac for the KEK B-Factory. A prototype monitor was tested for its performance and characteristics. The experimental results in terms of both bench tests and beam tests by single-bunch electron beams were analyzed on the basis of equivalent-circuit models. The frequency response of the monitor agreed well with a lumped equivalent-circuit model for both time- and frequency-domain measurements. The position dependence and its frequency characteristics of the monitor also agreed well with a distributed equivalent-circuit model for both time- and frequency-domain measurements. The rise time of the monitor was about 3 ns, which indicated a poor response for short-pulse beams (<1) ns. The reason could be attributed to the stray inductance of the ceramic solid resistor and not very good frequency response of the ferrite core. (orig.).

  17. New analysis and performance of a wall-current monitor

    International Nuclear Information System (INIS)

    Suwada, T.; Urano, T.; Kobayashi, H.; Tamiya, K.; Asami, A.

    1997-01-01

    A new wall-current monitor has been developed in order to reinforce the beam-monitoring system in the PF 2.5-GeV linac for the KEK B-Factory. A prototype monitor was tested for its performance and characteristics. The experimental results in terms of both bench tests and beam tests by single-bunch electron beams were analyzed on the basis of equivalent-circuit models. The frequency response of the monitor agreed well with a lumped equivalent-circuit model for both time- and frequency-domain measurements. The position dependence and its frequency characteristics of the monitor also agreed well with a distributed equivalent-circuit model for both time- and frequency-domain measurements. The rise time of the monitor was about 3 ns, which indicated a poor response for short-pulse beams (<1) ns. The reason could be attributed to the stray inductance of the ceramic solid resistor and not very good frequency response of the ferrite core. (orig.)

  18. Effects of Repeated-Sprint Training in Hypoxia on Sea-Level Performance: A Meta-Analysis.

    Science.gov (United States)

    Brocherie, Franck; Girard, Olivier; Faiss, Raphaël; Millet, Grégoire P

    2017-08-01

    Repeated-sprint training in hypoxia (RSH) is a recent intervention regarding which numerous studies have reported effects on sea-level physical performance outcomes that are debated. No previous study has performed a meta-analysis of the effects of RSH. We systematically reviewed the literature and meta-analyzed the effects of RSH versus repeated-sprint training in normoxia (RSN) on key components of sea-level physical performance, i.e., best and mean (all sprint) performance during repeated-sprint exercise and aerobic capacity (i.e., maximal oxygen uptake [[Formula: see text

  19. Systems, methods and computer-readable media for modeling cell performance fade of rechargeable electrochemical devices

    Science.gov (United States)

    Gering, Kevin L

    2013-08-27

    A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware periodically samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics of the electrochemical cell. The computing system also develops a mechanistic level model of the electrochemical cell to determine performance fade characteristics of the electrochemical cell and analyzing the mechanistic level model to estimate performance fade characteristics over aging of a similar electrochemical cell. The mechanistic level model uses first constant-current pulses applied to the electrochemical cell at a first aging period and at three or more current values bracketing a first exchange current density. The mechanistic level model also is based on second constant-current pulses applied to the electrochemical cell at a second aging period and at three or more current values bracketing the second exchange current density.

  20. Timing of return from altitude training for optimal sea level performance.

    Science.gov (United States)

    Chapman, Robert F; Laymon Stickford, Abigail S; Lundby, Carsten; Levine, Benjamin D

    2014-04-01

    While a number of published studies exist to guide endurance athletes with the best practices regarding implementation of altitude training, a key unanswered question concerns the proper timing of return to sea level prior to major competitions. Evidence reviewed here suggests that, altogether, the deacclimatization responses of hematological, ventilatory, and biomechanical factors with return to sea level likely interact to determine the best timing for competitive performance.

  1. ASPECT (Automated System-level Performance Evaluation and Characterization Tool), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — SSCI has developed a suite of SAA tools and an analysis capability referred to as ASPECT (Automated System-level Performance Evaluation and Characterization Tool)....

  2. Students' Level of Boredom, Boredom Coping Strategies, Epistemic Curiosity, and Graded Performance

    Science.gov (United States)

    Eren, Altay; Coskun, Hamit

    2016-01-01

    The authors examined the relationships among students' levels of boredom, boredom coping strategies, epistemic curiosity, and graded performance regarding mathematics lessons, with the intention to explore the mediating roles of boredom coping strategies and epistemic curiosity in the relationship between the level of boredom and graded…

  3. Secondhand smoke exposure and serum cotinine levels among current smokers in the USA.

    Science.gov (United States)

    Lindsay, Ryan P; Tsoh, Janice Y; Sung, Hai-Yen; Max, Wendy

    2016-03-01

    Secondhand smoke (SHS) likely provides additional exposure to nicotine and toxins for smokers, but has been understudied. Our objective was to determine whether SHS exposure among smokers yields detectable differences in cotinine levels compared with unexposed smokers at the population level. Using the US National Health and Nutrition Examination Survey (NHANES) for the years 1999-2012, we compared serum cotinine levels of 4547 current adult cigarette smokers stratified by self-reported SHS exposure sources (home and/or work) and smoking intensity. A weighted multivariable linear regression model determined the association between SHS exposure and cotinine levels among smokers. Smokers with SHS exposure at home (43.8%) had higher cotinine levels (β=0.483, p≤0.001) compared with those with no SHS exposure at home after controlling for the number of cigarettes smoked per day and number of days smoked in the previous 5 days, survey year, age, gender and education. Smokers with SHS exposure at work (20.0%) did not have significantly higher cotinine levels after adjustment. The adjusted geometric mean cotinine levels of light smokers (1-9 cigarettes per day) with no SHS exposure, exposure at work only, home only, and both home and work were 52.0, 62.7, 67.2, 74.4 ng/mL, respectively, compared with 219.4, 220.9, 255.2, 250.5 ng/mL among moderate/heavy smokers (≥10 cigarettes per day). Smokers living in residences where others smoke inside the home had significantly higher cotinine levels than smokers reporting no SHS exposure, regardless of individual smoking intensity. Future research should target the role that SHS exposure may have in nicotine dependence, cessation outcomes and other health impacts among smokers. 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/

  4. Modelling effects of current distributions on performance of micro-tubular hollow fibre solid oxide fuel cells

    International Nuclear Information System (INIS)

    Doraswami, U.; Droushiotis, N.; Kelsall, G.H.

    2010-01-01

    A three-dimensional model, considering mass, momentum, energy and charge conservation, was developed and the equations solved to describe the physico-chemical phenomena occurring within a single, micro-tubular hollow fibre solid oxide fuel cell (HF-SOFC). The model was used to investigate the spatial distributions of potential, current and reactants in a 10 mm long HF-SOFC. The predicted effects of location of current collectors, electrode conductivities, cathode thickness and porosity were analysed to minimise the ranges of current density distributions and maximise performance by judicious design. To decrease the computational load, azimuthal symmetry was assumed to model 50 and 100 mm long reactors in 2-D. With connectors at the same end of the HF-SOFC operating at a cell voltage of 0.5 V and a mean 5 kA m -2 , axial potential drops of ca. 0.14 V in the cathode were predicted, comparable to the cathode activation overpotential. Those potential drops caused average current densities to decrease from ca. 6.5 to ca.1 kA m -2 as HF-SOFC length increased from 10 to 100 mm, at which much of the length was inactive. Peak power densities were predicted to vary from 3.8 to -2 , depending on the location of the current collectors; performance increased with increasing cathode thickness and decreasing porosity.

  5. Coupled-analysis of current transport performance and thermal behaviour of conduction-cooled Bi-2223/Ag double-pancake coil for magnetic sail spacecraft

    Energy Technology Data Exchange (ETDEWEB)

    Nagasaki, Y., E-mail: nagasaki@rish.kyoto-u.ac.jp [Research Institute of Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Nakamura, T. [Graduate School of Engineering, Kyoto University, Kyotodaigakukatsura, Nishikyo, Kyoto 615-8530 (Japan); Funaki, I. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 252-5210 (Japan); Ashida, Y.; Yamakawa, H. [Research Institute of Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2013-09-15

    Highlights: • We model current transport and thermal performances of conduction-cooled HTS coil. • We investigate the effect of the longitudinal inhomogeneity of the HTS tape. • The analysis can precisely estimate performances of the conduction-cooled coil. • The longitudinal inhomogeneity of the HTS tape deteriorates coil performances. • Quench currents of the HTS coil are not consistent with the critical currents. -- Abstract: This paper investigated the quantitative current transport performance and thermal behaviour of a high temperature superconducting (HTS) coil, and the effect of the critical current inhomogeneity along the longitudinal direction of HTS tapes on the coil performances. We fabricated a double-pancake coil using a Bi-2223/Ag tape with a length of 200 m as a scale-down model for a magnetic sail spacecraft. We measured the current transport property and temperature rises during current applications of the HTS coil in a conduction-cooled system, and analytically reproduced the results on the basis of the percolation depinning model and three-dimensional heat balance equation. The percolation depinning model can describe the electric field versus current density of HTS tapes as a function of temperature and magnetic field vector, and we also introduced the longitudinal distribution of the local critical current of the HTS tape into this model. As a result, we can estimate the critical currents of the HTS coil within 10% error for a wide range of the operational temperatures from 45 to 80 K, and temperature rises on the coil during current applications. These results showed that our analysis and conduction-cooled system were successfully realized. The analysis also suggested that the critical current inhomogeneity along the length of the HTS tape deteriorated the current transport performance and thermal stability of the HTS coil. The present study contributes to the characterization of HTS coils and design of a coil system for the

  6. Coupled-analysis of current transport performance and thermal behaviour of conduction-cooled Bi-2223/Ag double-pancake coil for magnetic sail spacecraft

    International Nuclear Information System (INIS)

    Nagasaki, Y.; Nakamura, T.; Funaki, I.; Ashida, Y.; Yamakawa, H.

    2013-01-01

    Highlights: • We model current transport and thermal performances of conduction-cooled HTS coil. • We investigate the effect of the longitudinal inhomogeneity of the HTS tape. • The analysis can precisely estimate performances of the conduction-cooled coil. • The longitudinal inhomogeneity of the HTS tape deteriorates coil performances. • Quench currents of the HTS coil are not consistent with the critical currents. -- Abstract: This paper investigated the quantitative current transport performance and thermal behaviour of a high temperature superconducting (HTS) coil, and the effect of the critical current inhomogeneity along the longitudinal direction of HTS tapes on the coil performances. We fabricated a double-pancake coil using a Bi-2223/Ag tape with a length of 200 m as a scale-down model for a magnetic sail spacecraft. We measured the current transport property and temperature rises during current applications of the HTS coil in a conduction-cooled system, and analytically reproduced the results on the basis of the percolation depinning model and three-dimensional heat balance equation. The percolation depinning model can describe the electric field versus current density of HTS tapes as a function of temperature and magnetic field vector, and we also introduced the longitudinal distribution of the local critical current of the HTS tape into this model. As a result, we can estimate the critical currents of the HTS coil within 10% error for a wide range of the operational temperatures from 45 to 80 K, and temperature rises on the coil during current applications. These results showed that our analysis and conduction-cooled system were successfully realized. The analysis also suggested that the critical current inhomogeneity along the length of the HTS tape deteriorated the current transport performance and thermal stability of the HTS coil. The present study contributes to the characterization of HTS coils and design of a coil system for the

  7. Pengaruh Current Industry Relative Performance, Future Industry Relative Performance Dan Leverage Terhadap Praktik Manajemen Laba (Studi Komparasi Tiga Bank Konvensional Dan Tiga Bank Syariah

    Directory of Open Access Journals (Sweden)

    Surya Wahyudi

    2014-03-01

    Full Text Available Penelitian ini merupakan penelitian deskriptif qualitative yang bertujuan untuk mengetahui ada tidaknya pengaruh dari Current Industry Relative Performance (CRP, Future Industry Relative Performance (FRP dan Leverage (DEBT terhadap praktik manajemen laba pada Perbankan Indonesia. CRP, FRP dan DEBT diukur dengan mengggunakan rasio keuangan. Manajemen laba diukur dengan menggunakan total akrual. Data yang digunakan adalah data sekunder dengan karakteristik data time series yang berupa laporan keuangan triwulan bank (BM, BRI, BSM, BMI, dan BSMI tahun 2004 sampai dengan 2008. Dengan menggunakan regresi berganda dengan taraf nyata 5%. Hasil penelitian menunjukkan bahwa pada bank konvensional berdasarkan Uji Simultan, peubah CRP, FRP dan DEBT mempengaruhi praktik manajemen laba (AD, sedangkan berdasarkan Uji Parsial, hanya peubah CRP dan DEBT yang mempengaruhi praktik manajemen laba. Pada bank syariah, berdasarkan uji Simultan, peubah CRP, FRP, dan DEBT tidak ada yang mempengaruhi praktik manajemen laba (AD, sedangkan berdasarkan Uji Parsial, peubah CRP, FRP dan DEBT tidak mempengaruhi praktik manajemen laba.JEL Classification : G21, M12, M40Kata kunci : Current Industry Relative Performance (CRP, Future Industry Relative Performance (FRP, Leverage (DEBT, Manajemen Laba (Accrual Discretionary

  8. Saturation in Phosphene Size with Increasing Current Levels Delivered to Human Visual Cortex.

    Science.gov (United States)

    Bosking, William H; Sun, Ping; Ozker, Muge; Pei, Xiaomei; Foster, Brett L; Beauchamp, Michael S; Yoshor, Daniel

    2017-07-26

    electrical stimulation: phosphene size saturates at a relatively low current level. This finding implies that, with current methods, visual prosthetics will have a limited dynamic range available to control the production of spatial forms and that more advanced stimulation methods may be required. Copyright © 2017 the authors 0270-6474/17/377188-10$15.00/0.

  9. SENTINEL-2 LEVEL 1 PRODUCTS AND IMAGE PROCESSING PERFORMANCES

    Directory of Open Access Journals (Sweden)

    S. J. Baillarin

    2012-07-01

    . The stringent image quality requirements are also described, in particular the geo-location accuracy for both absolute (better than 12.5 m and multi-temporal (better than 0.3 pixels cases. Then, the prototyped image processing techniques (both radiometric and geometric will be addressed. The radiometric corrections will be first introduced. They consist mainly in dark signal and detector relative sensitivity correction, crosstalk correction and MTF restoration. Then, a special focus will be done on the geometric corrections. In particular the innovative method of automatic enhancement of the geometric physical model will be detailed. This method takes advantage of a Global Reference Image database, perfectly geo-referenced, to correct the physical geometric model of each image taken. The processing is based on an automatic image matching process which provides accurate ground control points between a given band of the image to refine and a reference image, allowing to dynamically calibrate the viewing model. The generation of the Global Reference Image database made of Sentinel-2 pre-calibrated mono-spectral images will be also addressed. In order to perform independent validation of the prototyping activity, an image simulator dedicated to Sentinel-2 has been set up. Thanks to this, a set of images have been simulated from various source images and combining different acquisition conditions and landscapes (mountains, deserts, cities …. Given disturbances have been also simulated so as to estimate the end to end performance of the processing chain. Finally, the radiometric and geometric performances obtained by the prototype will be presented. In particular, the geo-location performance of the level-1C products which widely fulfils the image quality requirements will be provided.

  10. SENTINEL-2 Level 1 Products and Image Processing Performances

    Science.gov (United States)

    Baillarin, S. J.; Meygret, A.; Dechoz, C.; Petrucci, B.; Lacherade, S.; Tremas, T.; Isola, C.; Martimort, P.; Spoto, F.

    2012-07-01

    stringent image quality requirements are also described, in particular the geo-location accuracy for both absolute (better than 12.5 m) and multi-temporal (better than 0.3 pixels) cases. Then, the prototyped image processing techniques (both radiometric and geometric) will be addressed. The radiometric corrections will be first introduced. They consist mainly in dark signal and detector relative sensitivity correction, crosstalk correction and MTF restoration. Then, a special focus will be done on the geometric corrections. In particular the innovative method of automatic enhancement of the geometric physical model will be detailed. This method takes advantage of a Global Reference Image database, perfectly geo-referenced, to correct the physical geometric model of each image taken. The processing is based on an automatic image matching process which provides accurate ground control points between a given band of the image to refine and a reference image, allowing to dynamically calibrate the viewing model. The generation of the Global Reference Image database made of Sentinel-2 pre-calibrated mono-spectral images will be also addressed. In order to perform independent validation of the prototyping activity, an image simulator dedicated to Sentinel-2 has been set up. Thanks to this, a set of images have been simulated from various source images and combining different acquisition conditions and landscapes (mountains, deserts, cities …). Given disturbances have been also simulated so as to estimate the end to end performance of the processing chain. Finally, the radiometric and geometric performances obtained by the prototype will be presented. In particular, the geo-location performance of the level-1C products which widely fulfils the image quality requirements will be provided.

  11. Influence of the optical fiber type on the performances of fiber-optics current sensor dedicated to plasma current measurement in ITER.

    Science.gov (United States)

    Aerssens, Matthieu; Descamps, Frédéric; Gusarov, Andrei; Mégret, Patrice; Moreau, Philippe; Wuilpart, Marc

    2015-07-01

    In this paper, we compare, by means of simulations using the Jones formalism, the performances of several optical fiber types (low birefringence and spun fibers) for the measurement of plasma current in international thermonuclear experimental reactor (ITER). The main results presented in this paper concern the minimum value of the ratio between the beat length and the spun period, which allows meeting the ITER current measurement specifications. Assuming a high-birefringence spun fiber with a beat length of 3 mm, we demonstrate that the minimum ratio between the beat length and the spun period is 4.4 when considering a 28 m long sensing fiber surrounding the vacuum vessel. This minimum ratio rises to 10.14 when a 100 m long lead fiber connecting the interrogating system to the sensing fiber is taken into account.

  12. Current fluctuations in quantum absorption refrigerators

    Science.gov (United States)

    Segal, Dvira

    2018-05-01

    Absorption refrigerators transfer thermal energy from a cold bath to a hot bath without input power by utilizing heat from an additional "work" reservoir. Particularly interesting is a three-level design for a quantum absorption refrigerator, which can be optimized to reach the maximal (Carnot) cooling efficiency. Previous studies of three-level chillers focused on the behavior of the averaged cooling current. Here, we go beyond that and study the full counting statistics of heat exchange in a three-level chiller model. We explain how to obtain the complete cumulant generating function of the refrigerator in a steady state, then derive a partial cumulant generating function, which yields closed-form expressions for both the averaged cooling current and its noise. Our analytical results and simulations are beneficial for the design of nanoscale engines and cooling systems far from equilibrium, with their performance optimized according to different criteria, efficiency, power, fluctuations, and dissipation.

  13. Level-1 muon trigger performance with the full 2017 dataset

    CERN Document Server

    CMS Collaboration

    2018-01-01

    This document describes the performance of the CMS Level-1 Muon Trigger with the full dataset of 2017. Efficiency plots are included for each track finder (TF) individually and for the system as a whole. The efficiency is measured to be greater than 90% for all track finders.

  14. Semiquantitative analysis of gaps in microbiological performance of fish processing sector implementing current food safety management systems: a case study.

    Science.gov (United States)

    Onjong, Hillary Adawo; Wangoh, John; Njage, Patrick Murigu Kamau

    2014-08-01

    Fish processing plants still face microbial food safety-related product rejections and the associated economic losses, although they implement legislation, with well-established quality assurance guidelines and standards. We assessed the microbial performance of core control and assurance activities of fish exporting processors to offer suggestions for improvement using a case study. A microbiological assessment scheme was used to systematically analyze microbial counts in six selected critical sampling locations (CSLs). Nine small-, medium- and large-sized companies implementing current food safety management systems (FSMS) were studied. Samples were collected three times on each occasion (n = 324). Microbial indicators representing food safety, plant and personnel hygiene, and overall microbiological performance were analyzed. Microbiological distribution and safety profile levels for the CSLs were calculated. Performance of core control and assurance activities of the FSMS was also diagnosed using an FSMS diagnostic instrument. Final fish products from 67% of the companies were within the legally accepted microbiological limits. Salmonella was absent in all CSLs. Hands or gloves of workers from the majority of companies were highly contaminated with Staphylococcus aureus at levels above the recommended limits. Large-sized companies performed better in Enterobacteriaceae, Escherichia coli, and S. aureus than medium- and small-sized ones in a majority of the CSLs, including receipt of raw fish material, heading and gutting, and the condition of the fish processing tables and facilities before cleaning and sanitation. Fish products of 33% (3 of 9) of the companies and handling surfaces of 22% (2 of 9) of the companies showed high variability in Enterobacteriaceae counts. High variability in total viable counts and Enterobacteriaceae was noted on fish products and handling surfaces. Specific recommendations were made in core control and assurance activities

  15. Novel Differential Current Control Strategy Based on a Modified Three-Level SVPWM for Two Parallel-Connected Inverters

    DEFF Research Database (Denmark)

    Zorig, Abdelmalik; Barkat, Said; Belkheiri, Mohammed

    2017-01-01

    Recently, parallel inverters have been investigated to provide multilevel characteristics besides their advantage to increase the power system capacity, reliability, and efficiency. However, the issue of differential currents imbalance remains a challenge in parallel inverter operation. The distr......Recently, parallel inverters have been investigated to provide multilevel characteristics besides their advantage to increase the power system capacity, reliability, and efficiency. However, the issue of differential currents imbalance remains a challenge in parallel inverter operation....... The distribution of switching vectors of the resulting multilevel topology has a certain degree of self-differential current balancing properties. Nevertheless, the method alone is not sufficient to maintain balanced differential current in practical applications. This paper proposes a closed-loop differential...... current control method by introducing a control variable adjusting the dwell time of the selected switching vectors and thus maintaining the differential currents balanced without affecting the overall system performance. The control strategy, including distribution of switching sequence, selection...

  16. Current practice patterns of drain usage amongst UK and Irish surgeons performing bilateral breast reductions: Evidence down the drain.

    Science.gov (United States)

    Sugrue, Conor M; McInerney, Niall; Joyce, Cormac W; Jones, Deidre; Hussey, Alan J; Kelly, Jack L; Kerin, Michael J; Regan, Padraic J

    2015-01-01

    Bilateral breast reduction (BBR) is one of the most frequently performed female breast operations. Despite no evidence supporting efficacy of drain usage in BBRs, postoperative insertion is common. Recent high quality evidence demonstrating potential harm from drain use has subsequently challenged this traditional practice. The aim of this study is to assess the current practice patterns of drains usage by Plastic & Reconstructive and Breast Surgeons in UK and Ireland performing BBRs. An 18 question survey was created evaluating various aspects of BBR practice. UK and Irish Plastic & Reconstructive and Breast Surgeons were invited to participate by an email containing a link to a web-based survey. Statistical analysis was performed with student t-test and chi-square test. Two hundred and eleven responding surgeons were analysed, including 80.1% (171/211) Plastic Surgeons and 18.9% (40/211) Breast Surgeons. Of the responding surgeons, 71.6% (151/211) routinely inserted postoperative drains, for a mean of 1.32 days. Drains were used significantly less by surgeons performing ≥20 BBRs (p = 0.02). With the majority of BBRs performed as an inpatient procedure, there was a trend towards less drain usage in surgeons performing this procedure as an outpatient; however, this was not statistically significant (p = 0.07). Even with the high level of evidence demonstrating the safety of BBR without drains, they are still routinely utilised. In an era of evidence- based medicine, surgeons performing breast reductions must adopt the results from scientific research into their clinical practice.

  17. Direct atomic-level insight into the active sites of a high-performance PGM-free ORR catalyst

    Science.gov (United States)

    Chung, Hoon T.; Cullen, David A.; Higgins, Drew; Sneed, Brian T.; Holby, Edward F.; More, Karren L.; Zelenay, Piotr

    2017-08-01

    Platinum group metal-free (PGM-free) metal-nitrogen-carbon catalysts have emerged as a promising alternative to their costly platinum (Pt)-based counterparts in polymer electrolyte fuel cells (PEFCs) but still face some major challenges, including (i) the identification of the most relevant catalytic site for the oxygen reduction reaction (ORR) and (ii) demonstration of competitive PEFC performance under automotive-application conditions in the hydrogen (H2)-air fuel cell. Herein, we demonstrate H2-air performance gains achieved with an iron-nitrogen-carbon catalyst synthesized with two nitrogen precursors that developed hierarchical porosity. Current densities recorded in the kinetic region of cathode operation, at fuel cell voltages greater than ~0.75 V, were the same as those obtained with a Pt cathode at a loading of 0.1 milligram of Pt per centimeter squared. The proposed catalytic active site, carbon-embedded nitrogen-coordinated iron (FeN4), was directly visualized with aberration-corrected scanning transmission electron microscopy, and the contributions of these active sites associated with specific lattice-level carbon structures were explored computationally.

  18. Relationship between Corrosion Level of Rebar Embedded in Concrete, Corrosion Potential and Current Density Measured by Non-destructive Test Method

    International Nuclear Information System (INIS)

    Chung, Lan; Cho, Seung Ho; Roh, Young Sook; Kim, Joong Koo

    2004-01-01

    The purpose of this study is to identify corrosion mechanism and develop qualitative measurement method of corrosion level. Fist of all, structural behavior of each different level of corrosion states have been evaluated. And mathematical models that can predict corrosion level in terms of electric potential and corrosion intensity are proposed. Corrosion rate in reinforcing bar was investigated in this study using accelerated corrosion method due to electric potential differences based on Faradays law. Total 288 measurement spots were designed in terms of corrosion rates, diameter of reinforcing bars, and concrete cover thickness. Corrosion current densities and corrosion potentials of concrete were measured on these specimens using Gecor device. This study suggested the relationship between corrosion levels, and measured electric current density as follows

  19. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency's Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories

  20. Experimental Verification Of Hyper-V Performance Isolation Level

    Directory of Open Access Journals (Sweden)

    Krzysztof Rzecki

    2014-01-01

    Full Text Available The need for cost optimization in a broad sense constitutes the basis of operation of every enterprise. In the case of IT structure, which is present in almost every field of activity these days, one of the most commonly applied technologies leading to good cost-to-profit adjustment is virtualization. It consists in locating several operational systems with IT systems on a single server. In order for such optimization to be carried out correctly it has to be strictly controlled by means of allocating access to resources, which is known as performance isolation. Modern virtualizers allow to set up this allocation in quantitative terms (the number of processors, size of RAM, or disc space. It appears, however, that in qualitative terms (processor's time, RAM or hard disc bandwidth the actual allocation of resources does not always correspond with this configuration. This paper provides an experimental presentation of the achievable level of performance isolation of the Hyper-V virtualizer.

  1. Effect of different levels of copper on growth performance and cecal ecosystem of newly weaned piglets

    Directory of Open Access Journals (Sweden)

    Dai-Wen Chen

    2010-11-01

    Full Text Available The current study aimed to investigate the effects of different levels of copper sulfate on the growth performance and cecal ecosystem in newly weaned piglets. One hundred piglets weaned at 28±2 d were randomly allocated to 4 treatments with 5 replicates of 5 piglets each. Piglets received for 28 d the base diet with i no addition (control or with copper addition (from copper sulfate at ii 100, iii 175, and iv 250 mg/kg-1. On day 21, twenty piglets were randomly selected (one from each replicate to slaughter and investigate the population and diversity of cecal microorganisms. The results showed that the diets containing 175 and 250 mg/kg-1 copper improved the average daily gain (ADG by 51% and 60% and decreased the feed to gain ratio (F/G by 21% and 16%, respectively. Adding 175 or 250 mg/kg-1 copper improved crude protein, ether extract, calcium and phosphorus digestibility. Viable counts of Enterobacteriaceae and Lactobacilli in cecum tended to be reduced, while the concentrations of cecal volatile fatty acids (VFA were increased in pigs fed diet supplemented as copper level increased. Polymerase chain reaction (PCR results showed that adding 175 or 250 mg/kg-1 copper reduced the lactobacilli in cecum. Denaturing gradient gel electrophoresis (DGGE maps showed that band numbers and intensity of cecal bacterial 16S rDNA decreased as the copper levels increased. The results suggested that the effects of high dietary copper on microflora and their activities and metabolic products might contribute to the intestinal health and result in improved growth performance.

  2. Effect of different levels of copper on growth performance and cecal ecosystem of newly weaned piglets

    Directory of Open Access Journals (Sweden)

    Shao-Feng Mei

    Full Text Available The current study aimed to investigate the effects of different levels of copper sulfate on the growth performance and cecal ecosystem in newly weaned piglets. One hundred piglets weaned at 28±2 d were randomly allocated to 4 treatments with 5 replicates of 5 piglets each. Piglets received for 28 d the base diet with i no addition (control or with copper addition (from copper sulfate at ii 100, iii 175, and iv 250 mg/kg–1. On day 21, twenty piglets were randomly selected (one from each replicate to slaughter and investigate the population and diversity of cecal microorganisms. The results showed that the diets containing 175 and 250 mg/kg–1 copper improved the average daily gain (ADG by 51% and 60% and decreased the feed to gain ratio (F/G by 21% and 16%, respectively. Adding 175 or 250 mg/kg–1 copper improved crude protein, ether extract, calcium and phosphorus digestibility. Viable counts of Enterobacteriaceae and Lactobacilli in cecum tended to be reduced, while the concentrations of cecal volatile fatty acids (VFA were increased in pigs fed diet supplemented as copper level increased. Polymerase chain reaction (PCR results showed that adding 175 or 250 mg/kg–1 copper reduced the lactobacilli in cecum. Denaturing gradient gel electrophoresis (DGGE maps showed that band numbers and intensity of cecal bacterial 16S rDNA decreased as the copper levels increased. The results suggested that the effects of high dietary copper on microflora and their activities and metabolic products might contribute to the intestinal health and result in improved growth performance.

  3. Current sensorless quick charger for lithium-ion batteries

    International Nuclear Information System (INIS)

    Tsang, K.M.; Chan, W.L.

    2011-01-01

    An efficient, simple and low cost quick charger based on the double-loop controller is proposed for the charging of lithium-ion (Li-ion) batteries. With positive and negative feedback of the battery voltage, charging profile similar to the constant current and constant voltage (CC-CV) charging strategy can be performed without actually sensing the charging current. The charging time can easily be shortened by raising the level of saturation in the primary voltage control loop. Experimental results are included to demonstrate the effectiveness of the battery charger. The charger could be a low cost and high performance replacement for existing Li-ion battery chargers.

  4. 40 CFR 57.302 - Performance level of interim constant controls.

    Science.gov (United States)

    2010-07-01

    ... correction of the effects of any serious deficiencies in the system. For the purpose of this paragraph, at... system if the smelter owner has not upgraded serious deficiencies in the constant control system in... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Performance level of interim constant...

  5. 10^{7}-A load-current B-dot monitor: Simulations, design, and performance

    Directory of Open Access Journals (Sweden)

    D. V. Rose

    2010-04-01

    Full Text Available A B-dot monitor that measures the current 6 cm from the axis of dynamic loads fielded on 10^{7}-A multiterawatt pulsed-power accelerators has been developed. The monitor improves upon the multimegampere load-current gauge described in Phys. Rev. ST Accel. Beams 11, 100401 (2008PRABFM1098-440210.1103/PhysRevSTAB.11.100401. The design of the improved monitor was developed using three-dimensional particle-in-cell simulations that model vacuum electron flow in the transmission line near the monitor. The simulations include important geometric features of the B-dot probe and model the deposition of electron energy within the probe. The simulations show that the improved design reduces by as much as a factor of 5 the electron energy deposition to the interior of the monitor. Data taken on accelerator shots demonstrate that the improved monitor works as well as the original monitor on shots with low-impedance loads, and delivers superior performance on higher-impedance-load shots.

  6. A Clinician Guide to Altitude Training for Optimal Endurance Exercise Performance at Sea Level.

    Science.gov (United States)

    Constantini, Keren; Wilhite, Daniel P; Chapman, Robert F

    2017-06-01

    Constantini, Keren, Daniel P. Wilhite, and Robert F. Chapman. A clinician guide to altitude training for optimal endurance exercise performance at sea level. High Alt Med Biol. 18:93-101, 2017.-For well over 50 years, endurance athletes have been utilizing altitude training in an effort to enhance performance in sea level competition. This brief review will offer the clinician a series of evidence-based best-practice guidelines on prealtitude and altitude training considerations, which can ultimately maximize performance improvement outcomes.

  7. Current and desired competency levels of secondary agricultural teachers in Pennsylvania

    Science.gov (United States)

    Elbert, Chanda Dehron

    nominal variables. A paired t-test was used to conduct an analysis of each competency area identified. Repeated measures were used to compare differences among categories. The data suggested that all teachers rated their desired level of competencies higher than their current competency levels. It was recommended that teachers be given the opportunity to attend additional professional development programs which will increase their knowledge base while working with special needs students.

  8. Taking it to another level: do personality-based human capital resources matter to firm performance?

    Science.gov (United States)

    Oh, In-Sue; Kim, Seongsu; Van Iddekinge, Chad H

    2015-05-01

    Drawing on the attraction-selection-attrition perspective, strategic human resource management (SHRM) scholarship, and recent human capital research, this study explores organization-level emergence of personality (i.e., personality-based human capital resources) and its direct, interactive, and (conditional) indirect effects on organization-level outcomes based on data from 6,709 managers across 71 firms. Results indicate that organization-level mean emotional stability, extraversion, and conscientiousness are positively related to organization-level managerial job satisfaction and labor productivity but not to financial performance. Furthermore, organization-level mean and variance in emotional stability interact to predict all three organization-level outcomes, and organization-level mean and variance in extraversion interact to predict firm financial performance. Specifically, the positive effects of organization-level mean emotional stability and extraversion are stronger when organization-level variance in these traits is lower. Finally, organization-level mean emotional stability, extraversion, and conscientiousness are all positively related to firm financial performance indirectly via labor productivity, and the indirect effects are more positive when organization-level variance in those personality traits is lower. Overall, the findings suggest that personality-based human capital resources demonstrate tangible effects on organization-level outcomes. Theoretical and practical implications of these findings are discussed along with study limitations and future research directions. (c) 2015 APA, all rights reserved.

  9. Lower hybrid heating and current drive in ignitor shear reversal scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Barbato, E; Pinaccione, L [Italian Agengy for New Technologies, Energy and the Environment, Centro Ricerche Frascati, Rome (Italy). Dip. Energia

    1996-05-01

    Injection of Lower Hybrid (LH) Wave power at 8 GHz is considered into IGNITOR shear reversal scenarios, characterized by a reduced plasma current and density. Power deposition calculation are performed to establish whether LH waves can be used both as central heating and off axis current drive tool. It turns out that LH waves can be used (a) for central plasma heating purpose during the current vamp phase, to freeze the shear reversed configuration, at the power level of {approx}10 MW. (b) to drive a current in the outer part of the plasma at the power level of 20 MW. In this way around 1/3-1/6 of the total current in the proper plasma position (i.e. where q is minimum) is driven.

  10. Design, installation and in-situ performance study of ultrasonic continuous level meter

    International Nuclear Information System (INIS)

    Surya Prakash, G.; Somayaji, K.M.

    1995-01-01

    The report discusses the design and the development of a continuous liquid level meter based on ultrasonic pulse-echo technique. A review of various methods for level measurement along with the details of pulse-echo technique are presented. Also discussed is the development of discrete level detectors based on ultrasonic techniques. Lastly, the procedures adopted for in-situ installation of these level meters in FBTR and RML are given along with the field performance study. Some of the typical merits and limitations of the method and the surface preparation procedure are also highlighted. (author) (author)

  11. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste. Although numerous caveats must be placed on the results, the general findings were as follows: Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories

  12. Effect of Lanthanum-Strontium Cathode Current-Collecting Layer on the Performance of Anode Supported Type Planar Solid Oxide Fuel Cells

    Science.gov (United States)

    Park, Sun-Young; Ji, Ho-Il; Kim, Hae-Ryoung; Yoon, Kyung Joong; Son, Ji-Won; Lee, Hae-Weon; Lee, Jong-Ho

    2013-07-01

    We applied screen-printed (La,Sr)CoO3 as a current-collecting layer of planar type unit-cell for lower temperature operation of SOFCs. In this study the effects of the cathode current-collecting layer on the performance of unit cell and symmetric half cell were investigated via AC and DC polarization experiments. According to our investigation, appropriately controlled current collecting layer was very effective to enhance the unit cell performance by reducing not only the ohmic resistance but also the polarization losses of SOFC cathode.

  13. Level tracking in detailed reactor simulations

    Energy Technology Data Exchange (ETDEWEB)

    Aktas, B.; Mahaffy, J.H. [Pennsylvania State Univ., University Park, PA (United States)

    1995-09-01

    We introduce a useful test problem for judging the performance of reactor safety codes in situations where moving two-phase mixture levels are present. The test problem tracks a two-phase liquid level as it rises and then falls back to its original position. Pure air exists above the level, and a low void air-water mixture is below the level. Conditions are subcooled and isothermal to remove complications resulting from failures of interfacial heat transfer packages to properly account for the level. Comparisons are made between the performance of current versions of CATHARE, RELAP5, TRAC-BF1, and TRAC-PF1. These system codes are based on finite-difference methods with a fixed, Eulerian staggered grid in space. When a partially filled cell with a mixture level discontinuity becomes the donor cell, the sharp changes in fluid properties across the interface results in numerical oscillations of various terms. Furthermore, the cell-to-cell convection of mass, momentum and energy are inaccurately predicted nearby a mixture level. To adequately model moving mixture levels, an efficient discontinuity tracking method for the finite-difference Eulerian approximations is described. This model had been implemented in the TRAC-BWR code for the two-phase mixture level tracking since the TRAC-BD1 Version (released April 1984). The result of the test problem run by the current version of TRAC-BF1/MOD1 with the mixture level tracking model shows some peculiar behavior of the variables such as velocities, pressures and interfacial terms. A systematic approach to improving performance of the tracking method is described. Implementing this approach in TRAC-BF1/MOD1 has shown a major improvement in the results.

  14. Variations in task constraints shape emergent performance outcomes and complexity levels in balancing.

    Science.gov (United States)

    Caballero Sánchez, Carla; Barbado Murillo, David; Davids, Keith; Moreno Hernández, Francisco J

    2016-06-01

    This study investigated the extent to which specific interacting constraints of performance might increase or decrease the emergent complexity in a movement system, and whether this could affect the relationship between observed movement variability and the central nervous system's capacity to adapt to perturbations during balancing. Fifty-two healthy volunteers performed eight trials where different performance constraints were manipulated: task difficulty (three levels) and visual biofeedback conditions (with and without the center of pressure (COP) displacement and a target displayed). Balance performance was assessed using COP-based measures: mean velocity magnitude (MVM) and bivariate variable error (BVE). To assess the complexity of COP, fuzzy entropy (FE) and detrended fluctuation analysis (DFA) were computed. ANOVAs showed that MVM and BVE increased when task difficulty increased. During biofeedback conditions, individuals showed higher MVM but lower BVE at the easiest level of task difficulty. Overall, higher FE and lower DFA values were observed when biofeedback was available. On the other hand, FE reduced and DFA increased as difficulty level increased, in the presence of biofeedback. However, when biofeedback was not available, the opposite trend in FE and DFA values was observed. Regardless of changes to task constraints and the variable investigated, balance performance was positively related to complexity in every condition. Data revealed how specificity of task constraints can result in an increase or decrease in complexity emerging in a neurobiological system during balance performance.

  15. Evaluation of Circulating Current Suppression Methods for Parallel Interleaved Inverters

    DEFF Research Database (Denmark)

    Gohil, Ghanshyamsinh Vijaysinh; Bede, Lorand; Teodorescu, Remus

    2016-01-01

    Two-level Voltage Source Converters (VSCs) are often connected in parallel to achieve desired current rating in multi-megawatt Wind Energy Conversion System (WECS). A multi-level converter can be realized by interleaving the carrier signals of the parallel VSCs. As a result, the harmonic perfor......-mance of the WECS can be significantly improved. However, the interleaving of the carrier signals may lead to the flow of circulating current between parallel VSCs and it is highly desirable to avoid/suppress this unwanted circulating current. A comparative evaluation of the different methods to avoid....../suppress the circulating current between the parallel interleaved VSCs is presented in this paper. The losses and the volume of the inductive components and the semiconductor losses are evaluated for the WECS with different circulating current suppression methods. Multi-objective optimizations of the inductive components...

  16. Performance assessment for a hypothetical low-level waste disposal facility

    International Nuclear Information System (INIS)

    Smith, C.S.; Rohe, M.J.; Ritter, P.D.

    1997-01-01

    Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study

  17. Performance assessment for a hypothetical low-level waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.S.; Rohe, M.J.; Ritter, P.D. [and others

    1997-01-01

    Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study.

  18. Comparing identically designed grayscale (50 phase level) and binary (5 phase levels) splitters: actual versus modeled performance

    Science.gov (United States)

    Lizotte, Todd E.; Ohar, Orest P.; Tuttle, Tracie

    2006-04-01

    Performance of diffractive optics is determined by high-quality design and a suitable fabrication process that can actually realize the design. Engineers who are tasked with developing or implementing a diffractive optic solution into a product need to take into consideration the risks of using grayscale versus binary fabrication processes. In many cases, grayscale design doesn't always provide the best solution or cost benefit during product development. This fabrication dilemma arises when the engineer has to select a source for design and/or fabrication. Engineers come face to face with reality in view of the fact that diffractive optic suppliers tend to provide their services on a "best effort basis". This can be very disheartening to an engineer who is trying to implement diffractive optics. This paper will compare and contrast the design and performance of a 1 to 24 beam, two dimensional; beam splitter fabricated using a fifty (50) phase level grayscale and a five (5) phase level binary fabrication methods. Optical modeling data will be presented showing both designs and the performance expected prior to fabrication. An overview of the optical testing methods used will be discussed including the specific test equipment and metrology techniques used to verify actual optical performance and fabricated dimensional stability of each optical element. Presentation of the two versions of the splitter will include data on fabrication dimensional errors, split beam-to-beam uniformity, split beam-to-beam spatial size uniformity and splitter efficiency as compared to the original intended design performance and models. This is a continuation of work from 2005, Laser Beam Shaping VI.

  19. Performance of the New Turbine Mid-Level Critical Care Ventilators.

    Science.gov (United States)

    Delgado, Carlos; Romero, Jose E; Puig, Jaume; Izquierdo, Ana; Ferrando, Carlos; Belda, F Javier; Soro, Marina

    2017-01-01

    During recent years, ventilators using turbines as flow-generating systems have become increasingly more relevant. This bench study was designed to compare triggering and pressurization of 7 turbine mid-level ICU ventilators. We used a dual-chamber lung model to test 7 mid-level ICU ventilators in pressure support mode with levels of 10, 15, and 20 cm H 2 O with 2 PEEP levels of 5 cm H 2 O and the minimum level allowed by the ventilator. A ventilator was connected to the master chamber to simulate 2 different effort levels. Pressure drop, trigger delay time, time to minimum pressure, and pressure time products (PTP) during trigger and the first 300 and 500 ms were analyzed. In the trigger evaluation, the Savina had the highest delay time, whereas the C2, the V60, and the Trilogy had the lowest pressure drops and PTP values in both effort levels. In pressurization capacity assessment using ideal PTP300 and PTP500 percentages, the C2 and the V680 had the best results, and the Carina and the Savina had lower values, with no differences between both effort levels. Differences between PEEP levels did not seem to be relevant. Pressure support mode for tested ventilators worked properly, but pressurization capacity and trigger function performance were clearly superior in the newest machines. The use of PEEP did not modify the results. Copyright © 2017 by Daedalus Enterprises.

  20. Simulation of enhanced tokamak performance on DIII-D using fast wave current drive

    International Nuclear Information System (INIS)

    Grassie, J.S. de; Lin-Liu, Y.R.; Petty, C.C.; Pinsker, R.I.; Chan, V.S.; Prater, R.; John, H. St.; Baity, F.W.; Goulding, R.H.; Hoffman, D.H.

    1993-01-01

    The fast magnetosonic wave is now recognized to be a leading candidate for noninductive current drive for the tokamak reactor due to the ability of the wave to penetrate to the hot dense core region. Fast wave current drive (FWCD) experiments on DIII-D have realized up to 120 kA of rf current drive, with up to 40% of the plasma current driven noninductively. The success of these experiments at 60 MHz with a 2 MW transmitter source capability has led to a major upgrade of the FWCD system. Two additional transmitters, 30 to 120 MHz, with a 2 MW source capability each, will be added together with two new four-strap antennas in early 1994. Another major thrust of the DIII-D program is to develop advanced tokamak modes of operation, simultaneously demonstrating improvements in confinement and stability in quasi-steady-state operation. In some of the initial advanced tokamak experiments on DIII-D with neutral beam heated (NBI) discharges it has been demonstrated that energy confinement time can be improved by rapidly elongating the plasma to force the current density profile to be more centrally peaked. However, this high-l i phase of the discharge with the commensurate improvement in confinement is transient as the current density profile relaxes. By applying FWCD to the core of such a κ-ramped discharge it may be possible to sustain the high internal inductance and elevated confinement. Using computational tools validated on the initial DIII-D FWCD experiments we find that such a high-l i advanced tokamak discharge should be capable of sustainment at the 1 MA level with the upgraded capability of the FWCD system. (author) 16 refs., 3 figs., 1 tab

  1. Current R and D Status on High-Level Radioactive Waste Disposal in Selected Countries

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youn Myoung; Hwang, Yong Soo

    2008-11-15

    Current R and D status of such countries moving forward as the United States, Sweden, France, Japan and a few other countries for high-level radioactive waste (HLW) disposal in deep geological formation has been reviewed. Even though no HLW repositories have not practically constructed nor operated yet, lots of related R and D are being proceeded in many countries as well as in Korea. Through this brief review further progress is anticipated in this related R and D area in Korea.

  2. Step-Up Partial Power DC-DC Converters for Two-Stage PV Systems with Interleaved Current Performance

    Directory of Open Access Journals (Sweden)

    Jaime Wladimir Zapata

    2018-02-01

    Full Text Available This work presents a partial power converter allowing us to obtain, with a single DC-DC converter, the same feature as the classical interleaved operation of two converters. More precisely, the proposed topology performs similarly as the input-parallel output-series (IPOS configuration reducing the current ripple at the input of the system and dividing the individual converters power rating, compared to a single converter. The proposed topology consists of a partial DC-DC converter processing only a fraction of the total power, thus allowing high efficiency. Experimental results are provided to validate the proposed converter topology with a Flyback-based 100 W test bench with a transformer turns ratio n 1 = n 2 . Experimental results show high performances reducing the input current ripple around 30 % , further increasing the conversion efficiency.

  3. Direct and indirect effects of ownership on firm-level environmental performance

    Czech Academy of Sciences Publication Activity Database

    Earnhart, D.; Lízal, Lubomír

    2007-01-01

    Roč. 45, č. 4 (2007), s. 66-87 ISSN 0012-8775 Institutional research plan: CEZ:AV0Z70850503 Keywords : ownership structure * firm-level environmental performance * transition economy Subject RIV: AH - Economics Impact factor: 0.413, year: 2007

  4. Levels of Management Commitment: A Moderator the Structural Relationships among Critical Success Factors of TQM, World-Class Performance in Operations, and Company Financial Performance

    Directory of Open Access Journals (Sweden)

    Wakhid Slamet Ciptono

    2012-01-01

    Full Text Available This study investigates the moderating impacts of the three levels of management commitment (top, middle, and low levels on the structural relationships among the constructs— six critical success factors of TQM (quality improvement program, supervisory leadership, supplier involvement, management commitment, training to improve products/services, cross-functional relationships; world-class performance in operations (world-class company practices, operational excellence practices, company non-financial performance; and company financial performance. It uses a sample of 1,332 managers in 140 strategic business units (SBUs within 49 oil and gas companies in Indonesia. The empirical results indicate that the goodness-of-fit of the unconstrained model is much better than that of the constrained model, and this is an indicative that the three level of management moderates the structural relationships among the constructs. Those are, three levels of management act as a moderator variable between critical success factors of TQM, world-class company practices, operational excellence practices, company non-financial performance, and company financial performance. Results further reveal that world-class performances in operations (world-class company practices, operational excellence practices, and company non-financial performance were positively mediated the impact of critical success factors of TQM on company financial performance. Results also point out that five of six critical success factors of TQM positively associated with world-class company practices and operational excellence practices under the three levels of management (top, middle, low. World-class company practices and operational excellence practices have direct and significant effects on company non-financial performance (productivity, operational reliability. Furthermore, empirical results suggest that there is a positive and significant relationship between company non

  5. Growth Performance of Red Sokoto Bucks Fed Inclusion levels of ...

    African Journals Online (AJOL)

    This study was carried out to evaluate the growth performance of red Sokoto bucks fed two (2) inclusion levels of rawwater soaked and lime soaked Hibiscus sabdariffa seeds in rice offal based diets. A total of twenty one (21) red Sokoto bucks were randomly allotted into seven treatments with three (3) bucks per group while ...

  6. Effect Of Different Protein Levels on The Performance Of Growing ...

    African Journals Online (AJOL)

    T4 was superior to other treatments in terms of feed to gain ratio, efficiency of feed utilization and reproductive performance. Snails in T1 with 10% CP failed to lay eggs and had the least developed reproductive system. A diet of 15-20% C. P is therefore recommended for growing snails. Key words: Protein levels, snails, ...

  7. RELATIONSHIP BETWEEN THE LEVEL OF SELF-EFFICACY, PERFORMANCE INDICATORS, AND PARTICIPATION IN YOUTH BASKETBALL

    Directory of Open Access Journals (Sweden)

    Enrique Ortega

    2009-01-01

    Full Text Available The present study analyzed the relationship between the level of self-efficacy of the player with the ball in basketball, various performance indicators, and individual participation of the youth player in competition, with the goal of being able to establish initial values that help to define game styles and systems that are adapted to the characteristics of the youth player. In order to evaluate the levels of self-efficacy, a questionnaire was administered to 187 players from the under-16 age category. From a total of 22 games, the following variables related to the individual performance of the player were analyzed: a points scored; b shot attempts and shots made of 1, 2, and 3 points; c efficacy percentage of 1, 2, and 3-point shots; d rebounds made; and e personal fouls received. With regard to participation, the following variables were analyzed: f minutes played; g total time of ball possession; h number of ball possessions; i number of passes received; and j number of offensive phases in which the player participates. The results indicate that the performance and participation variables correctly classify 74.2% when differentiating between players with high and low levels of selfefficacy. The players with high levels of self-efficacy presented higher values in the different performance and participation variables than the players with low levels of self-efficacy.

  8. Low power arcjet performance

    Science.gov (United States)

    Curran, Francis M.; Sarmiento, Charles J.

    1990-01-01

    An experimental investigation was performed to evaluate arcjet operation at low power. A standard, 1 kW, constricted arcjet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power regime. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope. The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

  9. Performance Assessment Monitoring Plan for the Hanford Site Low-Level Waste Burial Grounds

    International Nuclear Information System (INIS)

    SONNICHSEN, J.C.

    2000-01-01

    As directed by the U.S. Department of Energy (DOE), Richland Operations Office (DOE-RL), Fluor Hanford, Inc. will implement the requirements of DOE Order 435.1, Radioactive Waste Management, as the requirements relate to the continued operation of the low-level waste disposal facilities on the Hanford Site. DOE Order 435.1 requires a disposal authorization statement authorizing operation (or continued operation) of a low-level waste disposal facility. The objective of this Order is to ensure that all DOE radioactive waste is managed in a manner that protects the environment and personnel and public health and safety. The manual (DOE Order 435.1 Manual) implementing the Order states that a disposal authorization statement shall be issued based on a review of the facility's performance assessment and composite analysis or appropriate Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980 documentation. The disposal authorization shall specify the limits and conditions on construction, design, operations, and closure of the low-level waste facility. Failure to obtain a disposal authorization statement shall result in shutdown of an operational disposal facility. In fulfillment of the requirements of DOE Order 435.1, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area and the 200 West Area Low-Level Burial Grounds. The disposal authorization statement constitutes approval of the performance assessment and composite analysis, authorizes operation of the facility, and includes conditions that the disposal facility must meet. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area Low-Level Burial Grounds be written and approved by the DOE-RL. The monitoring plan is to be updated and implemented within 1 year following issuance of the disposal authorization statement to

  10. The Artemis workbench for system-level performance evaluation of embedded systems

    NARCIS (Netherlands)

    Pimentel, A.D.

    2008-01-01

    In this paper, we present an overview of the Artemis workbench, which provides modelling and simulation methods and tools for efficient performance evaluation and exploration of heterogeneous embedded multimedia systems. More specifically, we describe the Artemis system-level modelling methodology,

  11. Influence of High Level Features of HVS on Performance of FSIM

    Directory of Open Access Journals (Sweden)

    P. Dostal

    2013-12-01

    Full Text Available In this paper the influence of information about high level features of Human Visual System (HVS on objective quality assessment is studied. This was done by extending the existing full-reference objective image quality metric – FSIM – where the different importance of certain areas of image is considered using Phase Congruency (PC algorithm. Here, the estimation of Region of Interest (ROI based on this algorithm is complemented by Fixation Density Maps (FDM containing the information about high level features of HVS. Use of another low level features based algorithm (Phase Spectrum of Fourier Transform was also considered and compared to the PC algorithm. The performance was evaluated qualitatively on images reconstructed according to ROI and quantitatively on images from LIVE database. The correlation between subjective and objective tests was calculated using Pearson’s Correlation Coefficient and Spearman’s Rank Order Coefficient. The statistical significance of the difference between correlation coefficients was assessed by Fisher r-to-z transformation. The performance of the metric was also compared to other state-of-the-art image quality metrics (SSIM, MS-SSIM, and FSIM.

  12. Evaluating Levels of Project Planning and their Effects on Performance in the Nigerian Construction Industry

    Directory of Open Access Journals (Sweden)

    Godwin Idoro

    2012-11-01

    Full Text Available This study compares the level of project planning on public andprivate sectors projects and its impact on performance. Thepurpose is to create awareness of the level and effectivenessof the planning done by public and private clients in the deliveryof construction projects. A questionnaire survey administeredto a sample of 130 client representatives selected by stratifi edrandom sampling from the population of public and private clientsin the Nigerian construction industry is used and analysed usingdescriptive statistics, the t-test and Spearman correlation test. Theresults show that the level of preconstruction planning on privatesector projects is higher than that of public sector projects whilethe level of contract planning done by the latter is higher thanthat of the former. Furthermore, the performance of private sectorprojects is higher than that of public sector projects in many of theparameters used. However, the level of preparation of life-cyclecharts that concern project delivery time in both public and privatesectors projects is low and the level of project planning in the twocategories of projects has a limited impact on project performance.The understanding of how public and private sectors projectsperform in planning and its impact are expected to assist publicand private clients to know the challenges ahead of them in theireffort to improve the planning and performance of their projects.

  13. Current high-level waste solidification technology

    International Nuclear Information System (INIS)

    Bonner, W.F.; Ross, W.A.

    1976-01-01

    Technology has been developed in the U.S. and abroad for solidification of high-level waste from nuclear power production. Several processes have been demonstrated with actual radioactive waste and are now being prepared for use in the commercial nuclear industry. Conversion of the waste to a glass form is favored because of its high degree of nondispersibility and safety

  14. Development of an Individual Work Performance Questionnaire

    NARCIS (Netherlands)

    Koopmans, L.; Bernaards, C.M.; Hildebrandt, V.H.; van Buuren, S.; van der Beek, A.J.; de Vet, H.C.W.

    2013-01-01

    The purpose of the current study is to develop a generic and short questionnaire to measure work performance at the individual level – the Individual Work Performance Questionnaire (IWPQ). The IWPQ was based on a four-dimensional conceptual framework, in which individual work performance consisted

  15. Performance of a wiped film evaporator with simulated high level waste slurries

    International Nuclear Information System (INIS)

    Dierks, R.D.; Bonner, W.F.

    1975-01-01

    The horizontal, reverse taper, wiped film evaporator that was evaluated demonstrated a number of positive characteristics with respect to its applicability in the solidification of nuclear fuel recovery process wastes. Foremost among these is its ability to remove the bulk (80 to 90 percent) of the liquid associated with any of the purex-type high level, intermediate level, or mixed waste slurries. The major disadvantage of the evaporator is its current inability to discharge a product that is low enough in liquid content to avoid sticking to the evaporator discharge nozzle. Also, while the indirect indications of the torque required to turn the rotor and the power drawn by the drive motor are indicative of the liquid content of the discharged product, no reliable correlation has been found to cover all of the possible flow rates and feed stock compositions that the evaporator may be required to handle. In addition, no reliable means has been found to indicate the presence or absence of product flow through the discharge nozzle. The lack of a positive means of moving the product concentrate out of the evaporator and into a high temperature receiver is an undesirable feature of the evaporator. Pulverized glass former, or frit, was added to the evaporator feedstock in a ratio of frit to metal oxides of 2 to 1, and the resulting mixture successfully evaporated to a concentrate containing about 50 percent solids. In general, the performance of the wiped film evaporator evaluated was favorable for its use in a nuclear waste fixation process, however further development of the rotor design, power input, and operating techniques will be required to produce a free flowing solid product

  16. Branch technical position for performance assessment of low-level radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    Campbell, A.C.; Abramson, L.; Byrne, R.M.

    1994-01-01

    The U.S. Nuclear Regulatory Commission has developed a Draft Branch Technical Position on Performance Assessment of Low-Level Radioactive Waste Disposal Facilities. The draft technical position addresses important issues in performance assessment modeling and provides a framework and technical basis for conducting and evaluating performance assessments in a disposal facility license application. The technical position also addresses specific technical policy issues and augments existing NRC guidance pertaining to LLW performance assessment

  17. Designing PV Incentive Programs to Promote Performance: A Reviewof Current Practice in the U.S.

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen; Wiser, Ryan; Bolinger, Mark

    2006-10-06

    In the U.S., the increasing financial support for customer-sited photovoltaic (PV) systems provided through publicly-funded incentive programs has heightened concerns about the long-term performance of these systems. Given the barriers that customers face to ensuring that their PV systems perform well, and the responsibility that PV incentive programs bear to ensure that public funds are prudently spent, these programs should, and often do, play a critical role in addressing PV system performance. To provide a point of reference for assessing the current state of the art, and to inform program design efforts going forward, we examine the approaches to encouraging PV system performance used by 32 prominent PV incentive programs in the U.S. We identify eight general strategies or groups of related strategies that these programs have used to address factors that affect performance, and describe key implementation details. Based on this review, we then offer recommendations for how PV incentive programs can be effectively designed to mitigate potential performance issues.

  18. Relationships among gender, cognitive style, academic major, and performance on the Piaget water-level task.

    Science.gov (United States)

    Hammer, R E; Hoffer, N; King, W L

    1995-06-01

    Many researchers have found that more college-age adults than would be expected fail Piaget's water-level task, with women failing more frequently than men. It has been hypothesized that differences in cognitive style may account for performance differences on the water-level task. In the present study, 27 male and 27 female architectural students and 27 male and 27 female liberal-arts students were assessed for their performance on both Piaget's Water-level Task and Witkin's Group Embedded Figures Test. No difference was found in performance of male and female architectural students on either task, but male liberal-arts students scored significantly higher than female liberal-arts students on both measures. A disembedding cognitive style predicted success on the water-level task for the architectural students but not for the liberal arts students.

  19. Changes in driving behavior and cognitive performance with different breath alcohol concentration levels.

    Science.gov (United States)

    Liu, Yung-Ching; Fu, Shing-Mei

    2007-06-01

    This study examines the changes in driving behavior and cognitive performance of drivers with different breath alcohol concentration (BrAC) levels. Eight licensed drivers, aged between 20 and 30 years, with BrAC levels of 0.00, 0.25, 0.4 and 0.5 mg/l performed simulated driving tests under high- and low-load conditions. Subjects were asked to assess their subjective psychological load at specified intervals and perform various tasks. The outcome was measured in terms of reaction times for task completion, accuracy rates, and driver's driving behavior. The effects of BrAC vary depending on the task. Performance of tasks involving attention shift, information processing, and short-term memory showed significant deterioration with increasing BrAC, while dangerous external vehicle driving behavior occurred only when the BrAC reached 0.4 mg/l and the deterioration was marked. We can conclude that the cognitive faculty is the first to be impaired by drinking resulting in deteriorated performance in tasks related to divided attention, short-term memory, logical reasoning, followed by visual perception. On the other hand, increasing alcohol dose may not pose an immediate impact on the external vehicle driving behavior but may negatively affect the driver's motor behavior even at low BrAC levels. Experience and will power could compensate for the negative influence of alcohol enabling the drivers to remain in full steering control. This lag between alcohol consumption and impaired driving performance may mislead the drivers in thinking that they are still capable of safe steering and cause them to ignore the potential dangers of drunk driving.

  20. Performance Assessment for the Idaho National Laboratory Remote-Handled Low-Level Waste Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Annette L. Schafer; A. Jeffrey Sondrup; Arthur S. Rood

    2012-05-01

    This performance assessment for the Remote-Handled Low-Level Radioactive Waste Disposal Facility at the Idaho National Laboratory documents the projected radiological dose impacts associated with the disposal of low-level radioactive waste at the facility. This assessment evaluates compliance with the applicable radiological criteria of the U.S. Department of Energy and the U.S. Environmental Protection Agency for protection of the public and the environment. The calculations involve modeling transport of radionuclides from buried waste to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses are calculated for both offsite receptors and individuals who inadvertently intrude into the waste after site closure. The results of the calculations are used to evaluate the future performance of the low-level radioactive waste disposal facility and to provide input for establishment of waste acceptance criteria. In addition, one-factor-at-a-time, Monte Carlo, and rank correlation analyses are included for sensitivity and uncertainty analysis. The comparison of the performance assessment results to the applicable performance objectives provides reasonable expectation that the performance objectives will be met

  1. Effects of Performance-Based Financial Incentives on Work Performance: A Study of Technical-Level Employees in the Private Sector in Sri Lanka

    Science.gov (United States)

    Wickramasinghe, Vathsala; Dabere, Sampath

    2012-01-01

    The objective of the study is to investigate the effect of performance-based financial incentives on work performance. The study hypothesized that the design features of performance-based financial incentive schemes themselves may influence individuals' work performance. For the study, survey methodology was used and 93 technical-level employees…

  2. Current practice of incineration of low-level institutional radioactive waste

    International Nuclear Information System (INIS)

    Cooley, L.R.; McCampbell, M.R.; Thompson, J.D.

    1981-02-01

    During 1972, 142 medical and academic institutions were surveyed to assess the current practice of incineration of low-level radioactive waste. This was one activity carried out by the University of Maryland as part of a contract with EG and G Idaho, Inc., to site a radioactive waste incineration system. Of those surveyed, 46 (approximately 32%) were presently incinerating some type of radioactive waste. All were using controlled-air, multistage incinerators. Incinerators were most often used to burn animal carcasses and other biological wastes (96%). The average size unit had a capacity of 113 kg/h. Disposal of liquid scintillation vials posed special problems; eight institutions incinerated full scintillation vials and five incinerated scintillation fluids in bulk form. Most institutions (87%) used the incinerator to dispose of other wastes in addition to radioactive wastes. About half (20) of the institutions incinerating radioactive wastes reported shortcomings in their incineration process; those most often mentioned were: problems with liquid scintillation wastes, ash removal, melting glass, and visible smoke. Frequently cited reasons for incinerating wastes were: less expensive than shipping for commercial shallow land burial, volume reduction, convenience, and closure of existing disposal sites

  3. Silicon Photomultipliers: Dark Current and its Statistical Spread

    Directory of Open Access Journals (Sweden)

    Roberto PAGANO

    2012-03-01

    Full Text Available Aim of this paper is to investigate on a statistical basis at the wafer level the relationship existing among the dark currents of the single pixel compared to the whole Silicon Photomultiplier array. This is the first time to our knowledge that such a comparison is made, crucial to pass this new technology to the semiconductor manufacturing standards. In particular, emission microscopy measurements and current measurements allowed us to conclude that optical trenches strongly improve the device performances.

  4. Investigating Patterns of Automation and Growth Performance among Low Level Users of Manufacturing Automation

    DEFF Research Database (Denmark)

    Matthiesen, Rikke Vestergaard; Kromann, Lene

    instrument with a new, innovative way of characterizing and measuring automation levels in the production process. The survey data is merged with elaborate Danish register data on economic performance, market, and worker characteristics. The data is available from 2000 to 2010 across a broad range......-movers; companies that develop their level of automation further and companies that remain on the 2005 level up until 2010. We compare the presence of drivers and enablers in the 5-year period leading up to 2005 and investigate patterns in growth performance on a range of economic indicators between the two groups....... However, the cross sectional nature of most studies prohibits analysis of direction; is growth and economic performance the driver of manufacturing technology investment or vice versa. Longitudinal data is required to study this. The present study analyses panel data obtained using a retrospective survey...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-01

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

  6. Validating Performance Level Descriptors (PLDs) for the AP® Environmental Science Exam

    Science.gov (United States)

    Reshetar, Rosemary; Kaliski, Pamela; Chajewski, Michael; Lionberger, Karen

    2012-01-01

    This presentation summarizes a pilot study conducted after the May 2011 administration of the AP Environmental Science Exam. The study used analytical methods based on scaled anchoring as input to a Performance Level Descriptor validation process that solicited systematic input from subject matter experts.

  7. United States high-level radioactive waste management program: Current status and plans

    International Nuclear Information System (INIS)

    Williams, J.

    1992-01-01

    The inventory of spent fuel in storage at reactor sites in the United States is approximately 20,000 metric tons heavy metal (MTHM). It is increasing at a rate of 1700 to 2100 MTHM per year. According to current projections, by the time the last license for the current generation of nuclear reactors expires, there will be an estimated total of 84,000 MTHm. No commercial reprocessing capacity exists or is planned in the US. Therefore, the continued storage of spent fuel is required. The majority of spent fuel remains in the spent fuel pools of the utilities that generated it. Three utilities are presently supplementing pool capacity with on-site dry storage technologies, and four others are planning dry storage. Commercial utilities are responsible for managing their spent fuel until the Federal waste management system, now under development, accepts spent fuel for storage and disposal. Federal legislation charges the Office of Civilian Radioactive Waste Management (OCRWM) within the US Department of Energy (DOE) with responsibility for developing a system to permanently dispose of spent fuel and high level radioactive waste in a manner that protects the health and safety of the public and the quality of the environment. We are developing a waste management system consisting for three components: a mined geologic repository, with a projected start date of 2010; a monitored retrievable storage facility (MRS), scheduled to begin waste acceptance in 1998; and a transportation system to support MRS and repository operations. This paper discusses the background and framework for the program, as well as the current status and plans for management of spent nuclear fuel at commercial utilities; the OCRWM's development of a permanent geologic repository, an MRS, and a transportation system; the OCRWM's safety approach; the OCRWM's program management initiatives; and the OCRWM's external relations activities

  8. High-performance control of a three-phase voltage-source converter including feedforward compensation of the estimated load current

    International Nuclear Information System (INIS)

    Leon, Andres E.; Solsona, Jorge A.; Busada, Claudio; Chiacchiarini, Hector; Valla, Maria Ines

    2009-01-01

    In this paper a new control strategy for voltage-source converters (VSC) is introduced. The proposed strategy consists of a nonlinear feedback controller based on feedback linearization plus a feedforward compensation of the estimated load current. In our proposal an energy function and the direct-axis current are considered as outputs, in order to avoid the internal dynamics. In this way, a full linearization is obtained via nonlinear transformation and feedback. An estimate of the load current is feedforwarded to improve the performance of the whole system and to diminish the capacitor size. This estimation allows to obtain a more rugged and cheaper implementation. The estimate is calculated by using a nonlinear reduced-order observer. The proposal is validated through different tests. These tests include performance in presence of switching frequency, measurement filters delays, parameters uncertainties and disturbances in the input voltage.

  9. FED-A, an advanced performance FED based on low safety factor and current drive

    International Nuclear Information System (INIS)

    Peng, Y.K.M.; Rutherford, P.H.

    1983-08-01

    The FED-A study aims to quantify the potential improvement in cost-effectiveness of the Fusion Engineering Device (FED) by assuming low safety factor q (less than 2 as opposed to about 3) at the plasma edge and noninductive current drive (as opposed to only inductive current drive). The FED-A performance objectives are set to be : (1) ignition assuming International Tokamak Reactor (INTOR) plamsa confinement scaling, but still achieving a fusion power amplification Q greater than or equal to 5 when the confinement is degraded by a factor of 2; (2) neutron wall loading of about 1 MW/m 2 , with 0.5 MW/m 2 as a conservative lower bound; and (3) more clearly power-reactor-like operations, such as steady state

  10. Performance assessment overview for subseabed disposal of high level radioactive waste

    International Nuclear Information System (INIS)

    Klett, R.D.

    1997-06-01

    The Subseabed Disposal Project (SDP) was part of an international program that investigated the feasibility of high-level radioactive waste disposal in the deep ocean sediments. This report briefly describes the seven-step iterative performance assessment procedures used in this study and presents representative results of the last iteration. The results of the performance are compared to interim standards developed for the SDP, to other conceptual repositories, and to related metrics. The attributes, limitations, uncertainties, and remaining tasks in the SDP feasibility phase are discussed

  11. The effects of low levels of dietary trace minerals on the plasma levels, faecal excretion health and performance of pigs in a hot African climate

    Directory of Open Access Journals (Sweden)

    M.H. Boma

    2009-09-01

    Full Text Available The present study was performed in order to evaluate the effects of lower than usual industry levels of dietary trace minerals on plasma levels, faecal excretion, performance, mortality and morbidity in growing-finishing pigs in a hot African climate. Group 1 (n =100 pigs received a diet with common industry levels of trace minerals. Group 2 (n =100 pigs received reduced dietary trace mineral levels but were fed the same basic diet as Group 1. Mortality, morbidity, pig performance and carcass measurements were evaluated. Two pigs in Group 1 and three pigs in Group 2 died. Thirteen pigs in Group 1 and 27 pigs in Group 2 were medically treated (P 0.05 by the dietary levels of these trace minerals. Plasma trace mineral concentrations were not affected by the dietary treatment.

  12. The impact of current infection levels on the cost-benefit of vaccination

    Directory of Open Access Journals (Sweden)

    Matt J. Keeling

    2017-12-01

    Full Text Available When considering a new vaccine programme or modifying an existing one, economic cost-benefit analysis, underpinned by predictive epidemiological modelling, is a key component. This analysis is intimately linked to the willingness to pay for additional QALYs (quality-adjusted life-years gained; currently in England and Wales a health programme is economically viable if the cost per QALY gained is less than £ 20,000, and models are often used to assess if a vaccine programme is likely to fall below this threshold cost. Before a programme begins, infection levels are generally high and therefore vaccination may be expected to have substantial effects and therefore will often be economically viable. However, once a programme is established, and infection rates are lower, it might be expected that a re-evaluation of the programme (using current incidence information will show it to be less cost-effective. This is the scenario we examine here with analytical tools and simple ODE models. Surprisingly we show that in most cases the benefits from maintaining an existing vaccination programme are at least equal to those of starting the programme initially, and in the majority of scenarios the differences between the two are minimal. In practical terms, this is an extremely helpful finding, allowing us to assert that the action of immunising individuals does not de-value the vaccination programme.

  13. Mixed low-level waste form evaluation

    International Nuclear Information System (INIS)

    Pohl, P.I.; Cheng, Wu-Ching; Wheeler, T.; Waters, R.D.

    1997-01-01

    A scoping level evaluation of polyethylene encapsulation and vitreous waste forms for safe storage of mixed low-level waste was performed. Maximum permissible radionuclide concentrations were estimated for 15 indicator radionuclides disposed of at the Hanford and Savannah River sites with respect to protection of the groundwater and inadvertent intruder pathways. Nominal performance improvements of polyethylene and glass waste forms relative to grout are reported. These improvements in maximum permissible radionuclide concentrations depend strongly on the radionuclide of concern and pathway. Recommendations for future research include improving the current understanding of the performance of polymer waste forms, particularly macroencapsulation. To provide context to these estimates, the concentrations of radionuclides in treated DOE waste should be compared with the results of this study to determine required performance

  14. Input-Parallel Output-Parallel Three-Level DC/DC Converters With Interleaving Control Strategy for Minimizing and Balancing Capacitor Ripple Currents

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Gong, Zheng

    2017-01-01

    In this paper, the input-parallel output-parallel (IPOP) three-level (TL) DC/DC converters associated with the interleaving control strategy are proposed for minimizing and balancing the capacitor ripple currents. The proposed converters consist of two four-switch half-bridge three-level (HBTL) DC...

  15. What Drives Business Performance in Denmark

    DEFF Research Database (Denmark)

    Steiner, Bodo; Wang, Cong

    an overall positive and significant effect of social capital and religion on firm performance in Denmark. These effects are robust to different levels of aggregation (sample structure), different sampling years and alternative measures of firm performance (return on asset, current ratio, solvency ratio...... and profit margin)....

  16. Aggregation of Electric Current Consumption Features to Extract Maintenance KPIs

    Science.gov (United States)

    Simon, Victor; Johansson, Carl-Anders; Galar, Diego

    2017-09-01

    All electric powered machines offer the possibility of extracting information and calculating Key Performance Indicators (KPIs) from the electric current signal. Depending on the time window, sampling frequency and type of analysis, different indicators from the micro to macro level can be calculated for such aspects as maintenance, production, energy consumption etc. On the micro-level, the indicators are generally used for condition monitoring and diagnostics and are normally based on a short time window and a high sampling frequency. The macro indicators are normally based on a longer time window with a slower sampling frequency and are used as indicators for overall performance, cost or consumption. The indicators can be calculated directly from the current signal but can also be based on a combination of information from the current signal and operational data like rpm, position etc. One or several of those indicators can be used for prediction and prognostics of a machine's future behavior. This paper uses this technique to calculate indicators for maintenance and energy optimization in electric powered machines and fleets of machines, especially machine tools.

  17. Enhanced D-T supershot performance at high current using extensive lithium conditioning in TFTR

    International Nuclear Information System (INIS)

    Mansfield, D.K.; Strachan, J.D.; Bell, M.G.; Scott, S.D.; Budny, R.; Bell, R.E.; Bitter, M.; Darrow, D.S.; Fredrickson, E.; Grek, B.

    1995-05-01

    A substantial improvement in supershot fusion plasma performance has been realized by combining the enhanced confinement due to tritium fueling with the enhanced confinement due to extensive Li conditioning of the TFTR limiter. This combination has resulted in not only significantly higher global energy confinement times than had previously been obtained in high current supershots, but also the highest ratio of central fusion output power to input power observed to date

  18. Hierarchical Effects of School-, Classroom-, and Student-Level Factors on the Science Performance of Eighth-Grade Taiwanese Students

    Science.gov (United States)

    Tsai, Liang-Ting; Yang, Chih-Chien

    2015-05-01

    This study was conducted to understand the effect of student-, classroom-, and school-level factors on the science performance of 8th-grade Taiwanese students in the Trends in International Mathematics and Science Study (TIMSS) 2011 by using multilevel analysis. A total of 5,042 students from 153 classrooms of 150 schools participated in the TIMSS 2011 study, in which they were required to complete questionnaires. A 3-level multilevel analysis was used to assess the influence of factors at 3 levels on the science performance of 8th-grade Taiwanese students. The results showed that the provision of education resources at home, teachers' level of education, and school climate were the strongest predictor of science performance at the student, classroom, and school level, respectively. It was concluded that the science performance of 8th-grade Taiwanese students is driven largely by individual factors. Classroom-level factors accounted for a smaller proportion of the total variance in science performance than did school-level factors.

  19. Ractopamine levels on performance, carcass characteristics and quality of pig meat

    Directory of Open Access Journals (Sweden)

    Cesar Augusto Pospissil Garbossa

    2013-05-01

    Full Text Available This study evaluated the effect of ractopamine (RAC on the performance of finishing pigs and the meat quality of these animals. Seventy crossbred pigs (35 barrows and 35 females selected for high gain of lean meat, with initial weight of 77.1±0.32 kg were distributed in randomized blocks with five treatments (0, 5, 10, 15, and 20 ppm RAC in the diet and seven replications during 28 days. The experimental unit was represented by a male and a female pig. Regarding the performance variables, there was a linear increase in final weight with increasing levels of RAC, as well as in average daily weight gain. An improvement in feed conversion was observed for animals fed RAC, and the optimal level - estimated by the LRP model - was ~ 5 ppm. For feed intake, no significant effect on intake of digestible lysine and energy intake was observed. Carcass yield responses increased linearly with the RAC dose. Ash content, color component b* and loss drip linearly decreased with increasing doses of RAC. There was also a significant difference in the percentage of ether extract and crude protein in the loin, and treatment with 20 ppm RAC showed a lower amount of protein and larger amounts of lipids. Moisture content, color component L*, weight loss by cooking and defrosting, shear force and pH were not affected by the treatment. Concerning the lipid oxidation, there was no effect of RAC on the concentration of TBARS (thiobarbituric acid reactive substances under cooling and under freezing. Thus, all ractopamine levels improve performance compared with control and do not negatively affect the quality of fresh, chilled or frozen pig meat.

  20. Investigation of Remedial Education Course Scores as a Predictor of Introduction-Level Course Performances

    Science.gov (United States)

    Ulmer, Ward; Means, Darris R.; Cawthon, Tony W.; Kristensen, Sheryl A.

    2016-01-01

    This study explores whether performance in remedial English and remedial math is a predictor of success in a college-level introduction English or college-level math class; and whether demographic variables increase the likelihood of remedial English and remedial math as a predictor of success in a college-level introduction English or…

  1. Performance of high level waste forms and engineered barriers under repository conditions

    International Nuclear Information System (INIS)

    1991-02-01

    The IAEA initiated in 1977 a co-ordinated research programme on the ''Evaluation of Solidified High-Level Waste Forms'' which was terminated in 1983. As there was a continuing need for international collaboration in research on solidified high-level waste form and spent fuel, the IAEA initiated a new programme in 1984. The new programme, besides including spent fuel and SYNROC, also placed greater emphasis on the effect of the engineered barriers of future repositories on the properties of the waste form. These engineered barriers included containers, overpacks, buffer and backfill materials etc. as components of the ''near-field'' of the repository. The Co-ordinated Research Programme on the Performance of High-Level Waste Forms and Engineered Barriers Under Repository Conditions had the objectives of promoting the exchange of information on the experience gained by different Member States in experimental performance data and technical model evaluation of solidified high level waste forms, components of the waste package and the complete waste management system under conditions relevant to final repository disposal. The programme includes studies on both irradiated spent fuel and glass and ceramic forms as the final solidified waste forms. The following topics were discussed: Leaching of vitrified high-level wastes, modelling of glass behaviour in clay, salt and granite repositories, environmental impacts of radionuclide release, synroc use for high--level waste solidification, leachate-rock interactions, spent fuel disposal in deep geologic repositories and radionuclide release mechanisms from various fuel types, radiolysis and selective leaching correlated with matrix alteration. Refs, figs and tabs

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-09-01

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

  3. Performance Art at Secondary Level

    Science.gov (United States)

    Horn, Sheridan

    2009-01-01

    This article considers the far-reaching potential and the particular characteristics of performance art within the secondary art curriculum. It discusses the means by which an art department has incorporated it into their teaching curriculum at a state secondary school with reference to installations and the work of different performance artists…

  4. An Evaluation of Detect and Avoid (DAA) Displays for Unmanned Aircraft Systems: The Effect of Information Level and Display Location on Pilot Performance

    Science.gov (United States)

    Fern, Lisa; Rorie, R. Conrad; Pack, Jessica S.; Shively, R. Jay; Draper, Mark H.

    2015-01-01

    A consortium of government, industry and academia is currently working to establish minimum operational performance standards for Detect and Avoid (DAA) and Control and Communications (C2) systems in order to enable broader integration of Unmanned Aircraft Systems (UAS) into the National Airspace System (NAS). One subset of these performance standards will need to address the DAA display requirements that support an acceptable level of pilot performance. From a pilot's perspective, the DAA task is the maintenance of self separation and collision avoidance from other aircraft, utilizing the available information and controls within the Ground Control Station (GCS), including the DAA display. The pilot-in-the-loop DAA task requires the pilot to carry out three major functions: 1) detect a potential threat, 2) determine an appropriate resolution maneuver, and 3) execute that resolution maneuver via the GCS control and navigation interface(s). The purpose of the present study was to examine two main questions with respect to DAA display considerations that could impact pilots' ability to maintain well clear from other aircraft. First, what is the effect of a minimum (or basic) information display compared to an advanced information display on pilot performance? Second, what is the effect of display location on UAS pilot performance? Two levels of information level (basic, advanced) were compared across two levels of display location (standalone, integrated), for a total of four displays. The authors propose an eight-stage pilot-DAA interaction timeline from which several pilot response time metrics can be extracted. These metrics were compared across the four display conditions. The results indicate that the advanced displays had faster overall response times compared to the basic displays, however, there were no significant differences between the standalone and integrated displays. Implications of the findings on understanding pilot performance on the DAA task, the

  5. Prediction of habitual physical activity level and weight status from fundamental movement skill level.

    Science.gov (United States)

    Bryant, Elizabeth Sarah; James, Rob S; Birch, Samantha Louise; Duncan, Mike

    2014-01-01

    Fundamental movement skills (FMS) have been assessed in children in order to investigate the issues of the low proportion of children who meet physical activity (PA) guidelines and rising levels of obesity. The aim of this research was to identify whether previous or current FMS level is a better predictor of PA levels and weight status in children. In January 2012 (year 1), 281 children were recruited from one primary school in the West Midlands, UK. Children performed eight FMS three times, which were videoed and assessed using a subjective checklist. Sprint speed and jump height were measured objectively. Height and mass were measured to calculate the body mass index to determine the weight status. Skinfold calliper readings were used to calculate body fat percentage. One year later, in January 2013, all these tests were repeated on the same children, with the additional collection of PA data via the use of pedometers. Following multiple linear regression, it was identified that prior mastery in FMS was a better predictor of current PA, whereas current FMS was a better predictor of current weight status. Overall, FMS mastery is needed in childhood to be able to participate in PA and maintain a healthy weight status.

  6. Identity-level representations affect unfamiliar face matching performance in sequential but not simultaneous tasks.

    Science.gov (United States)

    Menon, Nadia; White, David; Kemp, Richard I

    2015-01-01

    According to cognitive and neurological models of the face-processing system, faces are represented at two levels of abstraction. First, image-based pictorial representations code a particular instance of a face and include information that is unrelated to identity-such as lighting, pose, and expression. Second, at a more abstract level, identity-specific representations combine information from various encounters with a single face. Here we tested whether identity-level representations mediate unfamiliar face matching performance. Across three experiments we manipulated identity attributions to pairs of target images and measured the effect on subsequent identification decisions. Participants were instructed that target images were either two photos of the same person (1ID condition) or photos of two different people (2ID condition). This manipulation consistently affected performance in sequential matching: 1ID instructions improved accuracy on "match" trials and caused participants to adopt a more liberal response bias than the 2ID condition. However, this manipulation did not affect performance in simultaneous matching. We conclude that identity-level representations, generated in working memory, influence the amount of variation tolerated between images, when making identity judgements in sequential face matching.

  7. Plasma current profile during current reversal in a tokamak

    International Nuclear Information System (INIS)

    Huang Jianguo; Yang Xuanzong; Zheng Shaobai; Feng Chunhua; Zhang Houxian; Wang Long

    1999-01-01

    Alternating current operation with one full cycle and a current level of 2.5 kA have been achieved in the CT-6B tokamak. The poloidal magnetic field in the plasma is measured with two internal magnetic probes in repeated discharges. The current distribution is reconstructed with an inversion algorithm. The inverse current first appears on the weak field side. The existence of magnetic surfaces and rotational transform provide particle confinement in the current reversal phase

  8. Performance evaluation of laser guided leveler

    Directory of Open Access Journals (Sweden)

    M.A. Hoque

    2014-12-01

    Full Text Available The study was conducted at Bangladesh Agricultural Research Institute (BARI farm on clay loam soil during Rabi season of 2010-2011. The treatments consisted of laser land leveling (T1 and control (non-leveled (T2. A preliminary field survey was done using staff gage. Initially a base station was established to dispense laser ray uniformly. The laser ray erected from base station guided the sensor of the stuff gage and the leveler. Elevation data was collected from the different points of the field and made an average. The maximum gage reading were 247.0 cm and the minimum gage reading was 219.2 cm. Average gage readings of the laser leveled plot was 235.66 cm that was settled for auto adjustment. Therefore, huge amount of soils (16.46 cm high was cut from the highest point and subsequently had to fill to the low points. Finally, an equal gage reading of 235.66 cm was observed after leveling the plot. The laser leveler (Leica MLS700 was used hitching with a TAFE tractor. The field was leveled with manual control initially and finally it was operated with auto adjustment. Two operators, 25 litter diesels and total 6 hours time were required during this leveling. Wheat was cultivated in leveled land (T1 and non-leveled land (T2. Laser leveling was insured for improvement in nutrient use efficiencies, option for precision farming, reduces weed problems, and improves uniformity of crop maturity. There was better distribution of water in leveled plot, which helped to reduce irrigation application time 1 hour. Due to uniformity of moisture content improved germination and crop establishment was found which reflected in higher plant population (239 m-2. Maximum yield (3.41 t ha-1 was obtained in T1 due to longer panicle (10.89 cm, more grain per plant (27.47 and 1000 grain weight (47.38 g compared to yield of T2 (2.62 t ha-1.

  9. Prediction of changes in memory performance by plasma homovanillic acid levels in clozapine-treated patients with schizophrenia.

    Science.gov (United States)

    Sumiyoshi, Tomiki; Roy, A; Kim, C-H; Jayathilake, K; Lee, M A; Sumiyoshi, C; Meltzer, H Y

    2004-12-01

    Cognitive dysfunction in schizophrenia has been demonstrated to be dependent, in part, on dopaminergic activity. Clozapine has been found to improve some domains of cognition, including verbal memory, in patients with schizophrenia. This study tested the hypothesis that plasma homovanillic acid (pHVA) levels, a peripheral measure of central dopaminergic activity, would predict the change in memory performance in patients with schizophrenia treated with clozapine. Twenty-seven male patients with schizophrenia received clozapine treatment for 6 weeks. Verbal list learning (VLL)-Delayed Recall (VLL-DR), a test of secondary verbal memory, was administered before and after clozapine treatment. Blood samples to measure pHVA levels were collected at baseline. Baseline pHVA levels were negatively correlated with change in performance on VLL-DR; the lower baseline pHVA level was associated with greater improvement in performance on VLL-DR during treatment with clozapine. Baseline pHVA levels in subjects who showed improvement in verbal memory during clozapine treatment ( n=13) were significantly lower than those in subjects whose memory performance did not improve ( n=14). The results of this study indicate that baseline pHVA levels predict the ability of clozapine to improve memory performance in patients with schizophrenia.

  10. Performance of evaporators in high level radioactive chemical waste service

    International Nuclear Information System (INIS)

    Jenkins, C.F.

    1997-01-01

    Chemical processing of nuclear fuels and targets at Savannah River Site resulted in generation of millions of gallons of liquid wastes. The wastes were further processed to reduce volume and allow for extended temporary storage of a more concentrated material. Waste evaporators have been a central point for waste reduction for many years. Currently, the transfer and processing of the concentrated wastes for permanent storage requires dilution and results in generation of significant quantities of additional liquid wastes. A new round of volume reduction is required to fit existing storage capacity and to allow for removal of older vessels from service. Evaporator design, performance and repairs are discussed in this report

  11. Performance of current intensive care unit ventilators during pressure and volume ventilation.

    Science.gov (United States)

    Marchese, Andrew D; Sulemanji, Demet; Chipman, Daniel; Villar, Jesús; Kacmarek, Robert M

    2011-07-01

    Intensive-care mechanical ventilators regularly enter the market, but the gas-delivery capabilities of many have never been assessed. We evaluated 6 intensive-care ventilators in the pressure support (PS), pressure assist/control (PA/C), and volume assist/control (VA/C) modes, with lung-model mechanics combinations of compliance and resistance of 60 mL/cm H(2)O and 10 cm H(2)O/L/s, 60 mL/cm H(2)O and 5 cm H(2)O/L/s, and 30 mL/cm H(2)O and 10 cm H(2)O/L/s, and inspiratory muscle effort of 5 and 10 cm H(2)O. PS and PA/C were set to 15 cm H(2)O, and PEEP to 5 and 15 cm H(2)O in all modes. During VA/C, tidal volume was set at 500 mL and inspiratory time was set at 0.8 second. Rise time and termination criteria were set at the manufacturers' defaults, and to an optimal level during PS and PA/C. There were marked differences in ventilator performance in all 3 modes. VA/C had the greatest difficulty meeting lung model demand and the greatest variability across all tested scenarios and ventilators. From high to low inspiratory muscle effort, pressure-to-trigger, time for pressure to return to baseline, and triggering pressure-time product decreased in all modes. With increasing resistance and decreasing compliance, tidal volume, pressure-to-trigger, time-to-trigger, time for pressure to return to baseline, time to 90% of peak pressure, and pressure-time product decreased. There were large differences between the default and optimal settings for all the variables in PS and PA/C. Performance was not affected by PEEP. Most of the tested ventilators performed at an acceptable level during the majority of evaluations, but some ventilators performed inadequately during specific settings. Bedside clinical evaluation is needed.

  12. Review on Available Information on Wind, Water Level, Current, Geology and Bathymetry in the DanWEC Area

    DEFF Research Database (Denmark)

    Margheritini, Lucia

    level, geology and bathymetry information at the DanWEC location. The present report has been prepared under the project No. 834101 “DanWEC Vaekstforum 2011”, task 3: “Collection and presentation of basic data about wind, current, water head, bathymetry and geology for the DanWEC site at the Port...

  13. Performance of modern tide gauges: towards mm-level accuracy

    Directory of Open Access Journals (Sweden)

    Belén Martín Míguez

    2012-09-01

    Full Text Available Considerable efforts are being made worldwide to upgrade tide gauge networks using new technologies. Because of the unique location of the Kerguelen Islands, the measurement of sea level there has received particular attention, with up to four systems equipped with modern sensors functioning simultaneously (two pressure tide gauges, a radar tide gauge, and a GPS-equipped buoy. We analysed and compared the sea level data obtained with these systems from 2003 to 2010, together with a time series of tide pole observations. This is the first time that a multi-comparison study with tide gauges has been undertaken over such a long time span and that the stability of modern radar tide gauges has been examined. The multi-comparison enabled us to evaluate the performance of the tide gauges in several frequency ranges, identify errors and estimate their magnitude. The drift of the pressure sensors (up to 8.0 mm/yr was found to be one of the most relevant sources of systematic error. Other sources of difference such as clock drift, scale error and different locations of the instruments were also detected. After correcting the time series of sea level for these errors we estimated an upper bound for the radar instrumental error in field condition at ~0.3 cm.

  14. Context for performance assessment

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1997-01-01

    In developing its recommendations on performance assessment for disposal of low-level radioactive waste, Scientific committee 87-3 of the National Council on Radiation Protection and Measurements (NCRP) has considered a number of topics that provide a context for the development of suitable approaches to performance assessment. This paper summarizes the Committee' discussions on these topics, including (1) the definition of low-level waste and its sources and properties, as they affect the variety of wastes that must be considered, (2) fundamental objectives and principles of radioactive waste disposal and their application to low-level waste, (3) current performance objectives for low-level waste disposal in the US, with particular emphasis on such unresolved issues of importance to performance assessment as the time frame for compliance, requirements for protection of groundwater and surface water, inclusion of doses from radon, demonstrating compliance with fixed performance objectives using highly uncertain model projections, and application of the principle that releases to the environment should be maintained as low as reasonably achievable (ALARA), (4) the role of active and passive institutional controls over disposal sites, (5) the role of the inadvertent human intruder in low-level waste disposal, (6) model validation and confidence in model outcomes, and (7) the concept of reasonable assurance of compliance

  15. Human Performance Modeling in Military Simulation: Current State of the Art and the Way Ahead (2002 TTCP HUM Group Meeting)

    National Research Council Canada - National Science Library

    2004-01-01

    .... This report examines the requirements for human performance modeling within the military, assesses the state of the practice in current operational models, documents ongoing human performance research and development (R and D...

  16. How current assessments of Sustainability Performance by Best Practice in the UN Global Compact challenge legitimacy

    DEFF Research Database (Denmark)

    Kjærgaard, Thomas

    The Scandinavian countries have been strong supporters of the UN Global Compact (UNGC) since the official launch in year 2000. This is best evidenced by the level of adoption of the UNGC, which is the most widely adopted broad sustainability-reporting standard in Scandinavia (Kjaergaard, submitted...... - in review). And since the UNGC in 2010 introduced the differentiation framework to their reporting standard, a significant number of Scandinavian corporations has chosen to report on an Advanced Level and self-assess their Sustainability Performance. Hence, in times where international opinion makers like...... element in assessing Sustainability Performance with the criteria for Advanced Level reporting in the UNGC differentiation framework. Though, previous empirical research by Kjaergaard (submitted, in review) has demonstrated that although the introduction of this framework generally should be acknowledged...

  17. Performance of the ATLAS first-level Trigger with first LHC Data

    CERN Document Server

    Lundberg, J; The ATLAS collaboration

    2010-01-01

    ATLAS is one of the two general-purpose detectors at the Large Hadron Collider (LHC). Its trigger system must reduce the anticipated proton collision rate of up to 40 MHz to a recordable event rate of 100-200 Hz. This is realized through a multi-level trigger system. The first-level trigger is implemented with custom-built electronics and makes an initial selection which reduces the rate to less than 100 kHz. The subsequent trigger selection is done in software run on PC farms. The first-level trigger decision is made by the central-trigger processor using information from coarse grained calorimeter information, dedicated muon-trigger detectors, and a variety of additional trigger inputs from detectors in the forward regions. We present the performance of the first-level trigger during the commissioning of the ATLAS detector during early LHC running. We cover the trigger strategies used during the different machine commissioning phases from first circulating beams and splash events to collisions. It is descri...

  18. Performance of a Tilt Current Meter in the Surf Zone

    DEFF Research Database (Denmark)

    Hansen, Asger Bendix; Carstensen, Stefan; Christensen, Drude Fritzbøger

    2017-01-01

    Tilt Current Meters (TCM’s) are relatively simple and inexpensive instruments for measuring currents in rivers and inthe sea. Their low cost and easy deployment means that a relatively large number of TCM’s can be deployed comparedto more conventional current meters such as Acoustic Doppler...

  19. The Impact of Performance Appraisal on the Motivational Level of the Employees

    OpenAIRE

    Hemani, Amir Ali

    2012-01-01

    The study aims to highlight the impact of performance appraisal on the motivational level of the employees. It is of great importance for an organization to retain its employees; this can be done by giving them opportunities and appraisals. The agenda of the study is to identify the relationship of compensation, promotion and motivation with performance appraisal. The research aims at the executive and labor class in the Kuala Lumpur, Malaysia. Open-ended structured interviews were conducted...

  20. Self-regulation of learning and performance level of elite youth soccer players

    NARCIS (Netherlands)

    Marije Elferink-Gemser; G. Pepping; G. Jordet; C. Visscher; T. Toering

    2012-01-01

    In learning and development, self-regulation can be described as the extent to which individuals are metacognitively, motivationally, and behaviourally proactive participants in their learning process (Zimmerman, 1989, 2006). We examined the relationship between self-regulation and performance level

  1. Comparisons of Student Achievement Levels by District Performance and Poverty. ACT Research Report Series 2016-11

    Science.gov (United States)

    Dougherty, Chrys; Shaw, Teresa

    2016-01-01

    This report looks at student achievement levels in Arkansas school districts disaggregated by district poverty and by the district's performance relative to other districts. We estimated district performance statistics by subject and grade level (4, 8, and 11-12) for longitudinal student cohorts, using statistical models that adjusted for district…

  2. Laboratory septic tank performance response to electrolytic stimulation.

    Science.gov (United States)

    Zaveri, Rahul M; Flora, Joseph R V

    2002-11-01

    This research investigated the effects of electrolytic stimulation on the performance of two laboratory-scale septic tanks. The tanks were fed a synthetic solution that included cellulose, peptone trypticase, beef extract, and urea. After a baseline period with no passed current, currents ranging from 100 to 500 mA were passed through the electrodes. The chemical oxygen demand (COD) removal efficiency from the tanks improved when a current was passed, with higher removal efficiencies observed at higher levels of passed current. Hydrolytic reactions resulted in ammonia and phosphate levels in the tanks that were higher than the influent. At currents > 300 mA, these hydrolytic reactions were suppressed, resulting in phosphate levels similar to the influent and ammonia levels lower than the influent because of the settling of ammonia-containing components of the feed solution. A slight increase in nitrate levels was observed when a current was passed, indicating minimal stimulation of nitrification activity. Abiotic studies confirmed that the COD can be removed via electrolysis and the removal was proportional to the passed current. Under the conditions of this study, the primary benefit of electrolytic stimulation of the septic tank is enhanced COD removal.

  3. Methods of calculating the post-closure performance of high-level waste repositories

    Energy Technology Data Exchange (ETDEWEB)

    Ross, B. (ed.)

    1989-02-01

    This report is intended as an overview of post-closure performance assessment methods for high-level radioactive waste repositories and is designed to give the reader a broad sense of the state of the art of this technology. As described here, ''the state of the art'' includes only what has been reported in report, journal, and conference proceedings literature through August 1987. There is a very large literature on the performance of high-level waste repositories. In order to make a review of this breadth manageable, its scope must be carefully defined. The essential principle followed is that only methods of calculating the long-term performance of waste repositories are described. The report is organized to reflect, in a generalized way, the logical order to steps that would be taken in a typical performance assessment. Chapter 2 describes ways of identifying scenarios and estimating their probabilities. Chapter 3 presents models used to determine the physical and chemical environment of a repository, including models of heat transfer, radiation, geochemistry, rock mechanics, brine migration, radiation effects on chemistry, and coupled processes. The next two chapters address the performance of specific barriers to release of radioactivity. Chapter 4 treats engineered barriers, including containers, waste forms, backfills around waste packages, shaft and borehole seals, and repository design features. Chapter 5 discusses natural barriers, including ground water systems and stability of salt formations. The final chapters address optics of general applicability to performance assessment models. Methods of sensitivity and uncertainty analysis are described in Chapter 6, and natural analogues of repositories are treated in Chapter 7. 473 refs., 19 figs., 2 tabs.

  4. Methods of calculating the post-closure performance of high-level waste repositories

    International Nuclear Information System (INIS)

    Ross, B.

    1989-02-01

    This report is intended as an overview of post-closure performance assessment methods for high-level radioactive waste repositories and is designed to give the reader a broad sense of the state of the art of this technology. As described here, ''the state of the art'' includes only what has been reported in report, journal, and conference proceedings literature through August 1987. There is a very large literature on the performance of high-level waste repositories. In order to make a review of this breadth manageable, its scope must be carefully defined. The essential principle followed is that only methods of calculating the long-term performance of waste repositories are described. The report is organized to reflect, in a generalized way, the logical order to steps that would be taken in a typical performance assessment. Chapter 2 describes ways of identifying scenarios and estimating their probabilities. Chapter 3 presents models used to determine the physical and chemical environment of a repository, including models of heat transfer, radiation, geochemistry, rock mechanics, brine migration, radiation effects on chemistry, and coupled processes. The next two chapters address the performance of specific barriers to release of radioactivity. Chapter 4 treats engineered barriers, including containers, waste forms, backfills around waste packages, shaft and borehole seals, and repository design features. Chapter 5 discusses natural barriers, including ground water systems and stability of salt formations. The final chapters address optics of general applicability to performance assessment models. Methods of sensitivity and uncertainty analysis are described in Chapter 6, and natural analogues of repositories are treated in Chapter 7. 473 refs., 19 figs., 2 tabs

  5. Hierarchical level oF managers’ abilities: A Moderator between Quality Management Practices and Company Financial Performance

    Directory of Open Access Journals (Sweden)

    Wakhid Slamet Ciptono

    2007-09-01

    Full Text Available This study investigates the moderating impacts of hierarchical level of managers’ abilities on the form and strength of all structural relationships between quality management practices and company financial performance. This study describes the structural relationships among the research constructs —six critical factors of quality management practices (quality improvement program, supervisory leadership, supplier involvement, management commitment, training to improve products/services, cross-functional relationships; the contextual factors of oil and gas companies—world-class performance in operations (world-class company practices, operational excellence practices, company non-financial performance; and company financial performance. It uses a sample of 1,332 managers in 140 strategic business units (SBUs within 49 oil and gas companies operating in Indonesia. The empirical results indicate that the goodness-of-fit of the unconstrained model is much better than that of the constrained model, and this is an indicator that hierarchical level of managers’ abilities moderates all structural relationships among the research constructs. Hence, the hierarchical level of managers’ abilities acts as a moderating variable of the whole model (i.e., among critical factors of quality management practices, world-class company practices, operational excellence practices, company non-financial performance, and company financial performance. It means that the major contribution of the hierarchical level of managers’ abilities is how to make changes in the organizational system. Top level managers’ abilities are deemed the most capable of making significant changes because of their broad sources of power and influence. Conversely, lower level managers’ abilities find it more difficult making significant changes in the system because of bureaucratic control processes that limit their actions —powerlessness or a chronic lack of autonomy

  6. Energy Yield Potential Estimation Using Marine Current Turbine Simulations for the Bosphorus

    DEFF Research Database (Denmark)

    Yazicioglu, Hasan; Tunc, K. M. Murat; Ozbek, Muammer

    2017-01-01

    . The differences in elevation and salinity ratios between these two seas cause strong underwater currents. Depending on the morphology of the canal the speed of the flow varies and at some specific locations the energy intensity reaches to sufficient levels where electricity generation by marine current turbines...... becomes economically feasible. In this study, several simulations are performed for a 10 MW marine turbine farm/ cluster whose location is selected by taking into account several factors such as the canal morphology, current speed and passage of vessels. 360 different simulations are performed for 15...... within the selected region, the analyses are performed for three different flow speeds corresponding to 10 % increase and decrease in the average value. For each simulation the annual energy yield and cluster efficiency are calculated....

  7. Performance assessment of the disposal of vitrified high-level waste in a clay layer

    International Nuclear Information System (INIS)

    Mallants, Dirk; Marivoet, Jan; Sillen, Xavier

    2001-01-01

    Deep disposal is considered a safe solution to the management of high-level radioactive waste. The safety is usually demonstrated by means of a performance assessment. This paper discusses the methodological aspects and some of the results obtained for the performance assessment of the disposal of vitrified high-level waste in a clay layer in Belgium. The calculations consider radionuclide migration through the following multi-barrier components, all of which contribute to the overall safety: (1) engineered barriers and the host clay layer, (2) overlying aquifer, and (3) biosphere. The interfaces between aquifers and biosphere are limited to the well and river pathway. Results of the performance assessment calculations are given in terms of the time evolution of the dose rates of the most important fission and activation products and actinides. The role of the glass matrix in the overall performance of the repository is also discussed

  8. Low-Frequency Pulsed Current Versus Kilohertz-Frequency Alternating Current: A Scoping Literature Review.

    Science.gov (United States)

    Vaz, Marco Aurélio; Frasson, Viviane Bortoluzzi

    2018-04-01

    To compare the effectiveness of low-frequency pulsed current versus kilohertz-frequency alternating current in terms of evoked force, discomfort level, current intensity, and muscle fatigability; to discuss the physiological mechanisms of each neuromuscular electrical stimulation type; and to determine if kilohertz-frequency alternating current is better than low-frequency pulsed current for clinical treatment. Articles were obtained from PubMed, Scopus, Cochrane Central Register of Controlled Trials, CINAHL, MEDLINE, and SPORTSDiscus databases using the terms Russian current or kilohertz current or alternating current or pulsed current or Aussie current and torque or discomfort or fatigue or current intensity, and through citation tracking up to July 2017. Two independent reviewers selected studies comparing the use of the 2 neuromuscular electrical stimulation currents. Studies describing maximal current intensity tolerated and the main effects of the 2 different current types on discomfort, muscle force, and fatigability were independently reviewed. Data were systematized according to (1) methodology; (2) electrical current characteristics; and (3) outcomes on discomfort level, evoked force, current intensity, and muscle fatigability. The search revealed 15 articles comparing the 2 current types. Kilohertz-frequency alternated current generated equal or less force, similar discomfort, similar current intensity for maximal tolerated neuromuscular electrical stimulation, and more fatigue compared with low-frequency pulsed current. Similar submaximal levels of evoked force revealed higher discomfort and current intensity for kilohertz-frequency alternated current compared with low-frequency pulsed current. Available evidence does not support the idea that kilohertz-frequency alternated current is better than low-frequency pulsed current for strength training and rehabilitation. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier

  9. Design and flight performance evaluation of the Mariners 6, 7, and 9 short-circuit current, open-circuit voltage transducers

    Science.gov (United States)

    Patterson, R. E.

    1973-01-01

    The purpose of the short-circuit voltage transducer is to provide engineering data to aid the evaluation of array performance during flight. The design, fabrication, calibration, and in-flight performance of the transducers onboard the Mariner 6, 7 and 9 spacecrafts are described. No significant differences were observed in the in-flight electrical performance of the three transducers. The transducers did experience significant losses due to coverslides or adhesive darkening, increased surface reflection, or spectral shifts within coverslide assembly. Mariner 6, 7 and 9 transducers showed non-cell current degradations of 3-1/2%, 3%, and 4%, respectively at Mars encounter and 6%, 3%, and 4-12%, respectively at end of mission. Mariner 9 solar Array Test 2 showed 3-12% current degradation while the transducer showed 4-12% degradation.

  10. Effect of dietary levels of a modified meat meal on performance and ...

    African Journals Online (AJOL)

    Effect of dietary levels of a modified meat meal on performance and small intestinal morphology of broiler chickens. ... African Journal of Biotechnology ... in Iran is mixed with 150 g wheat bran, 100 g feather meal and 150 g zeolite per kg.

  11. Fabrication of High-performance Sm-Fe-N isotropic bulk magnets by a combination of High-pressure compaction and current sintering

    Energy Technology Data Exchange (ETDEWEB)

    Takagi, Kenta, E-mail: k-takagi@aist.go.jp [Materials Research Institute for Sustainable Development, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560 (Japan); Nakayama, Hiroyuki; Ozaki, Kimihiro; Kobayashi, Keizo [Materials Research Institute for Sustainable Development, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560 (Japan)

    2012-04-15

    TbCu{sub 7}-type Sm-Fe-N coarse powders in the flake form were consolidated without a bonding medium using a low-thermal-load process of current sintering combined with high-pressure compression. When compacted at 1.2 GPa, the relative density of the powder was increased by 80% with close stacking of the flake particles. Although the subsequent current heating was only briefly performed at a low temperature of 400 Degree-Sign C to avoid decomposition, the compact was consolidated into a rigid bulk in which the particles were bonded at the atomic level. Finally, by using cyclic compaction, this process produced bulk magnets with a density of 92% that exhibited the highest maximum energy product (BH)max of 16.2 MGOe, which surpasses that of conventional isotropic Sm-Fe-N bond magnets. - Highlights: Black-Right-Pointing-Pointer We conduct a consolidation of Sm{sub 1}Fe{sub 7}N bulk magnets without thermal decomposition. Black-Right-Pointing-Pointer Rapid current sintering with high-pressure compaction is used as a low-thermal-load process. Black-Right-Pointing-Pointer In this process, sintering occurs at a temperature of 400 Degree-Sign C, which is below the decomposition point. Black-Right-Pointing-Pointer As a result, bulk magnets with a density of over 92% are obtained without decomposition. Black-Right-Pointing-Pointer These magnets exhibit the highest (BH)max (16.2 MGOe) among isotropic Sm-Fe-N magnets.

  12. Academic performance and student engagement in level 1 physics undergraduates

    International Nuclear Information System (INIS)

    Casey, M M; McVitie, S

    2009-01-01

    At the beginning of academic year 2007-08, staff in the Department of Physics and Astronomy at the University of Glasgow started to implement a number of substantial changes to the administration of the level 1 physics undergraduate class. The main aims were to improve the academic performance and progression statistics. With this in mind, a comprehensive system of learning support was introduced, the main remit being the provision of an improved personal contact and academic monitoring and support strategy for all students at level 1. The effects of low engagement with compulsory continuous assessment components had already been observed to have a significant effect on students sitting in the middle of the grade curve. Analysis of data from the 2007-08 class showed that even some nominally high-achieving students achieved lowered grades due to the effects of low engagement. Nonetheless, academic and other support measures put in place during 2007-08 played a part in raising the passrate for the level 1 physics class by approximately 8% as well as raising the progression rate by approximately 10%.

  13. Academic performance and student engagement in level 1 physics undergraduates

    Energy Technology Data Exchange (ETDEWEB)

    Casey, M M; McVitie, S [Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)], E-mail: m.casey@physics.gla.ac.uk

    2009-09-15

    At the beginning of academic year 2007-08, staff in the Department of Physics and Astronomy at the University of Glasgow started to implement a number of substantial changes to the administration of the level 1 physics undergraduate class. The main aims were to improve the academic performance and progression statistics. With this in mind, a comprehensive system of learning support was introduced, the main remit being the provision of an improved personal contact and academic monitoring and support strategy for all students at level 1. The effects of low engagement with compulsory continuous assessment components had already been observed to have a significant effect on students sitting in the middle of the grade curve. Analysis of data from the 2007-08 class showed that even some nominally high-achieving students achieved lowered grades due to the effects of low engagement. Nonetheless, academic and other support measures put in place during 2007-08 played a part in raising the passrate for the level 1 physics class by approximately 8% as well as raising the progression rate by approximately 10%.

  14. Inventory and characteristics of current and projected low-level radioactive materials and waste in the United States

    International Nuclear Information System (INIS)

    Bisaria, A.; Bugos, R.G.; Pope, R.B.; Salmon, R.; Storch, S.N.; Lester, P.B.

    1994-01-01

    The Integrated Data Base (IDB), under US Department of Energy (DOE) funding and guidance, provides an annual update of compiled data on current and projected inventories and characteristics of DOE and commercially owned radioactive wastes. The data base addresses also the inventories of DOE and commercial spent fuel. These data are derived from reliable information from government sources, open literature, technical reports, and direct contacts. The radioactive materials considered are spent nuclear fuel, high-level waste (HLW), transuranic (TRU) waste, low-level waste (LLW), commercial uranium mill tailings, environmental restoration wastes, and mixed-LLW. This paper primarily focuses on LLW inventory and characterization

  15. Assessment of the Water Levels and Currents at the Mississippi Bight During Hurricane Katrina.

    Science.gov (United States)

    Nwankwo, U. C.; Howden, S. D.; Dodd, D.; Wells, D. E.

    2017-12-01

    In an effort to extend the length of GPS baselines further offshore, the Hydrographic Science Research Center at the University of Southern Mississippi deployed a buoy which had a survey grade GPS receiver, an ADPC and a motion sensor unit in the Mississippi Bight in late 2004. The GPS data were initially processed using the Post Processed Kinematic technique with data from a nearby GPS base station on Horn Island. This processing technique discontinued when the storm (Hurricane Katrina) destroyed the base station in late August of 2005. However, since then a stand-alone positioning technique termed Precise Point Positioning (PPP) matured and allowed for the reprocessing of the buoy GPS data throughout Katrina. The processed GPS data were corrected for buoy angular motions using Tait Bryan transformation model. Tidal datums (Epoch 1983-2001) were transferred from the National Oceanic and Atmospheric Administration (NOAA) National Water Level at Waveland, Mississippi (Station ID 8747766) to the buoy using the Modified Range Ratio method. The maximum water level during the storm was found to be about 3.578m, relative to the transferred Mean Sea Level datum. The storm surge built over more than 24 hours, but fell back to normal levels in less than 3 hours. The maximum speed of the current with respect to the seafloor was recorded to be about 4knots towards the southeast as the storm surge moved back offshore.

  16. Voltage Balancing Method on Expert System for 51-Level MMC in High Voltage Direct Current Transmission

    Directory of Open Access Journals (Sweden)

    Yong Chen

    2016-01-01

    Full Text Available The Modular Multilevel Converters (MMC have been a spotlight for the high voltage and high power transmission systems. In the VSC-HVDC (High Voltage Direct Current based on Voltage Source Converter transmission system, the energy of DC link is stored in the distributed capacitors, and the difference of capacitors in parameters and charge rates causes capacitor voltage balance which affects the safety and stability of HVDC system. A method of MMC based on the expert system for reducing the frequency of the submodules (SMs of the IGBT switching frequency is proposed. Firstly, MMC with 51 levels for HVDC is designed. Secondly, the nearest level control (NLC for 51-level MMC is introduced. Thirdly, a modified capacitor voltage balancing method based on expert system for MMC-based HVDC transmission system is proposed. Finally, a simulation platform for 51-level Modular Multilevel Converter is constructed by using MATLAB/SIMULINK. The results indicate that the strategy proposed reduces the switching frequency on the premise of keeping submodule voltage basically identical, which greatly reduces the power losses for MMC-HVDC system.

  17. Trigger performance of mid-level ICU mechanical ventilators during assisted ventilation: a bench study.

    Science.gov (United States)

    Ferreira, Juliana C; Chipman, Daniel W; Kacmarek, Robert M

    2008-09-01

    To compare the triggering performance of mid-level ICU mechanical ventilators with a standard ICU mechanical ventilator. Experimental bench study. The respiratory care laboratory of a university-affiliated teaching hospital. A computerized mechanical lung model, the IngMar ASL5000. Ten mid-level ICU ventilators were compared to an ICU ventilator at two levels of lung model effort, three combinations of respiratory mechanics (normal, COPD and ARDS) and two modes of ventilation, volume and pressure assist/control. A total of 12 conditions were compared. Performance varied widely among ventilators. Mean inspiratory trigger time was ventilators. The mean inspiratory delay time (time from initiation of the breath to return of airway pressure to baseline) was longer than that for the ICU ventilator for all tested ventilators except one. The pressure drop during triggering (Ptrig) was comparable with that of the ICU ventilator for only two ventilators. Expiratory Settling Time (time for pressure to return to baseline) had the greatest variability among ventilators. Triggering differences among these mid-level ICU ventilators and with the ICU ventilator were identified. Some of these ventilators had a much poorer triggering response with high inspiratory effort than the ICU ventilator. These ventilators do not perform as well as ICU ventilators in patients with high ventilatory demand.

  18. Effects of dietary clinoptilolite and calcium levels on the performance and egg quality of commercial layers

    Directory of Open Access Journals (Sweden)

    DA Berto

    2013-09-01

    Full Text Available Among the different feed additives studied in poultry production, clinoptilolite, an aluminosilicate capable of adsorbing harmful substances and of improving live performance and egg and meat quality, was evaluated. The objective of the present study was to evaluate the influence of dietary clinoptilolite and calcium levels on the performance and egg quality of layers. In total, 576 layers were distributed according to a completely randomized experimental design in a 3 x 4 factorial arrangement (three calcium levels - 2.5, 3.1, or 3.7% and four clinoptilolite levels - 0.0, 0.15, 0.25, or 0.50%, with 12 treatments of six replicates of eight birds each. The experiment included four 28-d cycles. The experimental diets were based on corn and soybean meal. Results were submitted to analysis of variance and means were compared by the test of Tukey at 5% significance level using SISVAR statistical package. There was a significant interaction between the evaluated factors for egg production and feed conversion ratio per dozen eggs and egg mass. The lowest calcium level resulted in worse performance and eggshell quality. Clinoptilolite levels affected albumen and yolk content. It was concluded that up to 0.50% inclusion of clinoptilolite in layer diets does not benefit layer performance or eggshell quality. Although the inclusion of only 2.5% calcium in layer diets is not recommended, it is possible to add 3.1% because it promoted similar results as the recommended level of 3.7%.

  19. The role of massage in sports performance and rehabilitation: current evidence and future direction.

    Science.gov (United States)

    Brummitt, Jason

    2008-02-01

    Massage is a popular treatment choice of athletes, coaches, and sports physical therapists. Despite its purported benefits and frequent use, evidence demonstrating its efficacy is scarce. To identify current literature relating to sports massage and its role in effecting an athlete's psychological readiness, in enhancing sports performance, in recovery from exercise and competition, and in the treatment of sports related musculoskeletal injuries. Electronic databases were used to identify papers relevant to this review. The following keywords were searched: massage, sports injuries, athletic injuries, physical therapy, rehabilitation, delayed onset muscle soreness, sports psychology, sports performance, sports massage, sports recovery, soft tissue mobilization, deep transverse friction massage, pre-event, and post exercise. RESEARCH STUDIES PERTAINING TO THE FOLLOWING GENERAL CATEGORIES WERE IDENTIFIED AND REVIEWED: pre-event (physiological and psychological variables), sports performance, recovery, and rehabilitation. Despite the fact clinical research has been performed, a poor appreciation exists for the appropriate clinical use of sports massage. Additional studies examining the physiological and psychological effects of sports massage are necessary in order to assist the sports physical therapist in developing and implementing clinically significant evidence based programs or treatments.

  20. High School Sport Specialization Patterns of Current Division I Athletes

    OpenAIRE

    Post, Eric G.; Thein-Nissenbaum, Jill M.; Stiffler, Mikel R.; Brooks, M. Alison; Bell, David R.; Sanfilippo, Jennifer L.; Trigsted, Stephanie M.; Heiderscheit, Bryan C.; McGuine, Timothy A.

    2016-01-01

    Background: Sport specialization is a strategy to acquire superior sport performance in 1 sport but is associated with increased injury risk. Currently, the degree of high school specialization among Division I athletes is unknown. Hypothesis: College athletes will display increased rates of specialization as they progress through their high school careers. Study Design: Descriptive epidemiological study. Level of Evidence: Level 4. Methods: Three hundred forty-three athletes (115 female) rep...

  1. Performance and scalability of isolated DC-DC converter topologies in low voltage, high current applications

    Energy Technology Data Exchange (ETDEWEB)

    Vaisanen, V.

    2012-07-01

    Fuel cells are a promising alternative for clean and efficient energy production. A fuel cell is probably the most demanding of all distributed generation power sources. It resembles a solar cell in many ways, but sets strict limits to current ripple, common mode voltages and load variations. The typically low output voltage from the fuel cell stack needs to be boosted to a higher voltage level for grid interfacing. Due to the high electrical efficiency of the fuel cell, there is a need for high efficiency power converters, and in the case of low voltage, high current and galvanic isolation, the implementation of such converters is not a trivial task. This thesis presents galvanically isolated DC-DC converter topologies that have favorable characteristics for fuel cell usage and reviews the topologies from the viewpoint of electrical efficiency and cost efficiency. The focus is on evaluating the design issues when considering a single converter module having large current stresses. The dominating loss mechanism in low voltage, high current applications is conduction losses. In the case of MOSFETs, the conduction losses can be efficiently reduced by paralleling, but in the case of diodes, the effectiveness of paralleling depends strongly on the semiconductor material, diode parameters and output configuration. The transformer winding losses can be a major source of losses if the windings are not optimized according to the topology and the operating conditions. Transformer prototyping can be expensive and time consuming, and thus it is preferable to utilize various calculation methods during the design process in order to evaluate the performance of the transformer. This thesis reviews calculation methods for solid wire, litz wire and copper foil winding losses, and in order to evaluate the applicability of the methods, the calculations are compared against measurements and FEM simulations. By selecting a proper calculation method for each winding type, the winding

  2. Prospective single and multi-phase short-circuit current levels in the Dutch transmission, sub-transmission and distribution grids

    NARCIS (Netherlands)

    Janssen, A.L.J.; van Riet, M.J.M.; Smeets, R.P.P.; Kanters, J.; van den Akker, W.F.; Aanhaanen, G.L.P.

    2012-01-01

    As elsewhere in the world, also in the Netherlands utilities face an increase in the actual and future short-circuit current levels at all voltages. This development is provoked by the required increase in transmission capacity as well as the concentration of power generation capacity. Large

  3. Delayed enhancement of multitasking performance: Effects of anodal transcranial direct current stimulation on the prefrontal cortex.

    Science.gov (United States)

    Hsu, Wan-Yu; Zanto, Theodore P; Anguera, Joaquin A; Lin, Yung-Yang; Gazzaley, Adam

    2015-08-01

    The dorsolateral prefrontal cortex (DLPFC) has been proposed to play an important role in neural processes that underlie multitasking performance. However, this claim is underexplored in terms of direct causal evidence. The current study aimed to delineate the causal involvement of the DLPFC during multitasking by modulating neural activity with transcranial direct current stimulation (tDCS) prior to engagement in a demanding multitasking paradigm. The study is a single-blind, crossover, sham-controlled experiment. Anodal tDCS or sham tDCS was applied over left DLPFC in forty-one healthy young adults (aged 18-35 years) immediately before they engaged in a 3-D video game designed to assess multitasking performance. Participants were separated into three subgroups: real-sham (i.e., real tDCS in the first session, followed by sham tDCS in the second session 1 h later), sham-real (sham tDCS first session, real tDCS second session), and sham-sham (sham tDCS in both sessions). The real-sham group showed enhanced multitasking performance and decreased multitasking cost during the second session, compared to first session, suggesting delayed cognitive benefits of tDCS. Interestingly, performance benefits were observed only for multitasking and not on a single-task version of the game. No significant changes were found between the first and second sessions for either the sham-real or the sham-sham groups. These results suggest a causal role of left prefrontal cortex in facilitating the simultaneous performance of more than one task, or multitasking. Moreover, these findings reveal that anodal tDCS may have delayed benefits that reflect an enhanced rate of learning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. A performance assessment methodology for low-level radioactive waste disposal

    International Nuclear Information System (INIS)

    Deering, L.R.; Kozak, M.W.

    1990-01-01

    To demonstrate compliance with the performance objectives governing protection of the general population in 10 CFR 61.41, applicants for land disposal of low-level radioactive waste are required to conduct a pathways analysis, or quantitative evaluation of radionuclide release, transport through environmental media, and dose to man. The Nuclear Regulatory Commission staff defined a strategy and initiated a project at Sandia National Laboratories to develop a methodology for independently evaluating an applicant's analysis of postclosure performance. This performance assessment methodology was developed in five stages: (1) identification of environmental pathways, (2) ranking, the significance of the pathways, (3) identification and integration of models for pathway analyses, (4) identification and selection of computer codes and techniques for the methodology, and (5) implementation of the codes and documentation of the methodology. The final methodology implements analytical and simple numerical solutions for source term, ground-water flow and transport, surface water transport, air transport, food chain, and dosimetry analyses, as well as more complex numerical solutions for multidimensional or transient analyses when more detailed assessments are needed. The capability to perform both simple and complex analyses is accomplished through modular modeling, which permits substitution of various models and codes to analyze system components

  5. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM.

  6. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM

  7. Technical and tactical skills related to performance levels in tennis: A systematic review.

    Science.gov (United States)

    Kolman, Nikki S; Kramer, Tamara; Elferink-Gemser, Marije T; Huijgen, Barbara C H; Visscher, Chris

    2018-06-11

    The aim of this systematic review is to provide an overview of outcome measures and instruments identified in the literature for examining technical and tactical skills in tennis related to performance levels. Such instruments can be used to identify talent or the specific skill development training needs of particular players. Searches for this review were conducted using the PubMed, Web of Science, and PsycInfo databases. Out of 733 publications identified through these searches, 40 articles were considered relevant and included in this study. They were divided into three categories: (1) technical skills, (2) tactical skills and (3) integrated technical and tactical skills. There was strong evidence that technical skills (ball velocity and to a lesser extent ball accuracy) and tactical skills (decision making, anticipation, tactical knowledge and visual search strategies) differed among players according to their performance levels. However, integrated measurement of these skills is required, because winning a point largely hinges on a tactical decision to perform a particular stroke (i.e., technical execution). Therefore, future research should focus on examining the relationship between these skills and tennis performance and on the development of integrated methods for measuring these skills.

  8. AGGREGATION OF ELECTRIC CURRENT CONSUMPTION FEATURES TO EXTRACT MAINTENANCE KPIs

    Directory of Open Access Journals (Sweden)

    Victor SIMON

    2017-07-01

    Full Text Available All electric powered machines offer the possibility of extracting information and calculating Key Performance Indicators (KPIs from the electric current signal. Depending on the time window, sampling frequency and type of analysis, differ-ent indicators from the micro to macro level can be calculated for such aspects as maintenance, production, energy consumption etc. On the micro-level, the indicators are generally used for condition monitoring and diagnostics and are normally based on a short time window and a high sampling frequency. The macro indicators are normally based on a longer time window with a slower sampling frequency and are used as indicators for overall performance, cost or con-sumption. The indicators can be calculated directly from the current signal but can also be based on a combination of information from the current signal and operational data like rpm, position etc. One or several of those indicators can be used for prediction and prognostics of a machine’s future behavior. This paper uses this technique to calculate indicators for maintenance and energy optimization in electric powered machines and fleets of machines, especially machine tools.

  9. An integrated radar model solution for mission level performance and cost trades

    Science.gov (United States)

    Hodge, John; Duncan, Kerron; Zimmerman, Madeline; Drupp, Rob; Manno, Mike; Barrett, Donald; Smith, Amelia

    2017-05-01

    A fully integrated Mission-Level Radar model is in development as part of a multi-year effort under the Northrop Grumman Mission Systems (NGMS) sector's Model Based Engineering (MBE) initiative to digitally interconnect and unify previously separate performance and cost models. In 2016, an NGMS internal research and development (IR and D) funded multidisciplinary team integrated radio frequency (RF), power, control, size, weight, thermal, and cost models together using a commercial-off-the-shelf software, ModelCenter, for an Active Electronically Scanned Array (AESA) radar system. Each represented model was digitally connected with standard interfaces and unified to allow end-to-end mission system optimization and trade studies. The radar model was then linked to the Air Force's own mission modeling framework (AFSIM). The team first had to identify the necessary models, and with the aid of subject matter experts (SMEs) understand and document the inputs, outputs, and behaviors of the component models. This agile development process and collaboration enabled rapid integration of disparate models and the validation of their combined system performance. This MBE framework will allow NGMS to design systems more efficiently and affordably, optimize architectures, and provide increased value to the customer. The model integrates detailed component models that validate cost and performance at the physics level with high-level models that provide visualization of a platform mission. This connectivity of component to mission models allows hardware and software design solutions to be better optimized to meet mission needs, creating cost-optimal solutions for the customer, while reducing design cycle time through risk mitigation and early validation of design decisions.

  10. Social Responsibility in the Work Performance of the Teacher in the Context of Basic Education of the General Middle Level

    Directory of Open Access Journals (Sweden)

    Olga Josefina Álvarez Enríquez

    2017-02-01

    Full Text Available The current research had like general to purpose to analyze the social responsibility presents in the teacher’s job performance in the general half education level, in the school educational Unit Monte Carmelo Virgin, of the Valmore Rodriquez District. Is insected the ethnographic cualitative method. To gather information, was aplicated the observation technique and the interview in depth, which were processed through the categorization, the genral and individual structuring, contrasting, and theorizing. The validity and confiability let to confirm findings showing the necessity of the teacher’s permanent preparation in attention and training of the student in relationship to the expounded in the curriculum of general half level, so as the sensitization to the development of a pedagogical practice. Generating a theoric approximation of the mains themes relationed with the social responsibility of the teacher, the characteristies, the knowledges and interpretation of signes and meanings attributed by the social actors to the social responsibility in their job performance. The results of the study drove to a series of reflextions so important to show to exists a close pedagogical practice and imposed by the teacher’s, no taking the training of the student, emphasing a casy and simple knowledges transmission from the social responsibility perspective.

  11. Clinical instructors' perceptions of behaviors that comprise entry-level clinical performance in physical therapist students: a qualitative study.

    Science.gov (United States)

    Jette, Diane U; Bertoni, Alicia; Coots, Renee; Johnson, Heidi; McLaughlin, Catherine; Weisbach, Cody

    2007-07-01

    The purpose of this study was to qualitatively explore clinical instructors' (CIs) perceptions of students' behaviors that comprise entry-level clinical performance, as well as how those perceptions were integrated into their decision making. The participants were 21 physical therapists who were CIs for physical therapist students. Using a grounded theory approach, we conducted interviews, asking the question, "What is it about students' performance that makes you see them as entry-level therapists?" We determined common themes among the interviews and developed a schema to explain the decision-making process. Participants identified 7 attributes that, when demonstrated to a sufficient degree, illustrated to them students' ability to practice at the entry level. Those attributes were knowledge, clinical skills, safety, clinical decision making, self-directed learning, interpersonal communication, and professional demeanor. Participants viewed these attributes in concert to form a subjective "gut feeling" that a student demonstrated entry-level performance. A final theme emerged suggesting a definition of entry-level performance as "mentored independence." Participants reported evaluating students' performance based on attributes similar to those suggested by the American Physical Therapy Association's Physical Therapist Clinical Performance Instrument and previous research. However, subjectivity also was involved in their decision about whether students were able to practice at the entry level. Participants also concluded that entry-level students need not be independent in all clinical situations.

  12. Identification of Current Proficiency Level of Extension Competencies and the Competencies Needed for Extension Agents to Be Successful in the 21st Century

    Directory of Open Access Journals (Sweden)

    Dona Lakai

    2014-02-01

    Full Text Available In this era of globalization, competency is an issue of concern to any field of professionals and their clients. Competency is an integrated set of skills, knowledge, and attitudes that allow one to effectively carry out the activities of a given work to the standards expected in the employment context. The purpose of this descriptive survey study was to determine the current proficiency level of North Carolina Cooperative Extension agents’ competencies and the other competencies they need to develop to be successful in Cooperative Extension. Findings indicate that the current proficiency level of competency for Extension agents in North Carolina Cooperative Extension varies from moderate to high in all 42 items listed in the survey. Multiple regression analysis confirmed that Extension agents’ years of Extension experience and age were major determinants of their overall proficiency level. Extension agents’ proficiency levels did not vary with gender, level of education, professional association affiliation, job position, or area of job responsibility. The research revealed that emotional intelligence, interpersonal skills, flexibility for adapting to changing environments, and ability to manage resources were the most significant other competencies needed for Extension agents to be successful in current context.

  13. Performance assessment methodology (PAM) for low level radioactive waste (LLRW) disposal facilities

    International Nuclear Information System (INIS)

    Selander, W.N.

    1992-01-01

    An overview is given for Performance Assessment Methodology (PAM) for Low Level Radioactive Waste (LLRW) disposal technologies, as required for licensing and safety studies. This is a multi-disciplinary activity, emphasizing applied mathematics, mass transfer, geohydrology and radiotoxicity effects on humans. (author). 2 refs

  14. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 2: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  15. Overview of a performance assessment methodology for low-level radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    Kozak, M.W.; Chu, M.S.Y.

    1991-01-01

    A performance assessment methodology has been developed for use by the US Nuclear Regulatory Commission in evaluating license applications for low-level waste disposal facilities. This paper provides a summary and an overview of the modeling approaches selected for the methodology. The overview includes discussions of the philosophy and structure of the methodology. This performance assessment methodology is designed to provide the NRC with a tool for performing confirmatory analyses in support of license reviews related to postclosure performance. The methodology allows analyses of dose to individuals from off-site releases under normal conditions as well as on-site doses to inadvertent intruders. 24 refs., 1 tab

  16. The role of incline, performance level, and gender on the gross mechanical efficiency of roller ski skating.

    Science.gov (United States)

    Sandbakk, Oyvind; Hegge, Ann Magdalen; Ettema, Gertjan

    2013-01-01

    The ability to efficiently utilize metabolic energy to produce work is a key factor for endurance performance. The present study investigated the effects of incline, performance level, and gender on the gross mechanical efficiency during roller ski skating. Thirty-one male and nineteen female elite cross-country skiers performed a 5-min submaximal session at approximately 75% of VO2peak on a 5% inclined treadmill using the G3 skating technique. Thereafter, a 5-min session on a 12% incline using the G2 skating technique was performed at a similar work rate. Gross efficiency was calculated as the external work rate against rolling friction and gravity divided by the metabolic rate using gas exchange. Performance level was determined by the amount of skating FIS points [the Federation of International Skiing (FIS) approved scoring system for ski racing] where fewer points indicate a higher performance level. Strong significant correlations between work rate and metabolic rate within both inclines and gender were revealed (r = -0.89 to 0.98 and P gender differences being apparent. Significant correlations between gross efficiency and performance level were found for both inclines and genders (r = -0.65 to 0.81 and P genders used less metabolic energy to perform the same amount of work at steeper inclines, and that the better ranked elite male and female skiers skied more efficiently.

  17. Zero-Voltage Switching PWM Strategy Based Capacitor Current-Balancing Control for Half-Bridge Three-Level DC/DC Converter

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Zhang, Qi

    2018-01-01

    The current imbalance among the two input capacitors is one of the important issues of the half-bridge threelevel (HBTL) DC/DC converter, which would affect system performance and reliability. In this paper, a zero-voltage switching (ZVS) pulse-wide modulation (PWM) strategy including two operation...

  18. Radioactive Waste Management Complex low-level waste radiological performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Maheras, S.J.; Rood, A.S.; Magnuson, S.O.; Sussman, M.E.; Bhatt, R.N.

    1994-04-01

    This report documents the projected radiological dose impacts associated with the disposal of radioactive low-level waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. This radiological performance assessment was conducted to evaluate compliance with applicable radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the public and the environment. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses were made for both offsite receptors and individuals inadvertently intruding onto the site after closure. In addition, uncertainty and sensitivity analyses were performed. The results of the analyses indicate compliance with established radiological criteria and provide reasonable assurance that public health and safety will be protected.

  19. Radioactive Waste Management Complex low-level waste radiological performance assessment

    International Nuclear Information System (INIS)

    Maheras, S.J.; Rood, A.S.; Magnuson, S.O.; Sussman, M.E.; Bhatt, R.N.

    1994-04-01

    This report documents the projected radiological dose impacts associated with the disposal of radioactive low-level waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. This radiological performance assessment was conducted to evaluate compliance with applicable radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the public and the environment. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses were made for both offsite receptors and individuals inadvertently intruding onto the site after closure. In addition, uncertainty and sensitivity analyses were performed. The results of the analyses indicate compliance with established radiological criteria and provide reasonable assurance that public health and safety will be protected

  20. Postural performance and strategy in the unipedal stance of soccer players at different levels of competition.

    Science.gov (United States)

    Paillard, Thierry; Noé, Frédéric; Rivière, Terence; Marion, Vincent; Montoya, Richard; Dupui, Philippe

    2006-01-01

    Sport training enhances the ability to use somatosensory and otolithic information, which improves postural capabilities. Postural changes are different according to the sport practiced, but few authors have analyzed subjects' postural performances to discriminate the expertise level among highly skilled athletes within a specific discipline. To compare the postural performance and the postural strategy between soccer players at different levels of competition (national and regional). Repeated measures with 1 between-groups factor (level of competition: national or regional) and 1 within-groups factor (vision: eyes open or eyes closed). Dependent variables were center-of-pressure surface area and velocity; total spectral energy; and percentage of low-, medium-, and high-frequency band. Sports performance laboratory. Fifteen national male soccer players (age = 24 +/- 3 years, height = 179 +/- 5 cm, mass = 72 +/- 3 kg) and 15 regional male soccer players (age = 23 +/- 3 years, height = 174 +/- 4 cm, mass = 68 +/- 5 kg) participated in the study. The subjects performed posturographic tests with eyes open and closed. While subjects performed static and dynamic posturographic tests, we measured the center of foot pressure on a force platform. Spatiotemporal center-of-pressure measurements were used to evaluate the postural performance, and a frequency analysis of the center-of-pressure excursions (fast Fourier transform) was conducted to estimate the postural strategy. Within a laboratory task, national soccer players produced better postural performances than regional players and had a different postural strategy. The national players were more stable than the regional players and used proprioception and vision information differently. In the test conditions specific to playing soccer, level of playing experience influenced postural control performance measures and strategies.

  1. Current Background Noise Sources and Levels in the NASA Ames 40- by 80-Foot Wind Tunnel: A Status Report

    Science.gov (United States)

    Allen, Christopher S.; Jaeger, Stephen; Soderman, Paul; Koga, Dennis (Technical Monitor)

    1999-01-01

    diameters and types. The inflow microphone support strut is also a source of background noise but this source's impact may be minimized by careful design of the strut. In the present paper, the mechanisms mentioned above are discussed in detail. Their frequency and velocity ranges of dominance are defined and the differences between past and current facility background noise levels are presented. This paper gives valuable information for those wishing to make acoustic measurements in the 40x80. With this report and an estimate of the noise levels produced by the noise source of interest, it should be possible to determine the signal-to-noise ratios and measurement locations to successfully perform aeroacoustic testing in the NASA Ames Research Center's 40- by 80-Foot Wind Tunnel.

  2. The impact of manufacturing complexity drivers on performance-a preliminary study

    Science.gov (United States)

    Huah Leang, Suh; Mahmood, Wan Hasrulnizzam Wan; Rahman, Muhamad Arfauz A.

    2018-03-01

    Manufacturing systems, in pursuit of cost, time and flexibility optimisation are becoming more and more complex, exhibiting a dynamic and nonlinear behaviour. Unpredictability is a distinct characteristic of such behaviour and effects production planning significantly. Therefore, this study was undertaken to investigate the priority level and current achievement of manufacturing performance in Malaysia’s manufacturing industry and the complexity drivers on manufacturing productivity performance. The results showed that Malaysia’s manufacturing industry prioritised product quality and they managed to achieve a good on time delivery performance. However, for other manufacturing performance, there was a difference where the current achievement of manufacturing performances in Malaysia’s manufacturing industry is slightly lower than the priority given to them. The strong correlation of significant value for priority status was observed between efficient production levelling (finished goods) and finish product management while the strong correlation of significant value for current achievement was minimised the number of workstation and factory transportation system. This indicates that complexity drivers have an impact towards manufacturing performance. Consequently, it is necessary to identify complexity drivers to achieve well manufacturing performance.

  3. Performance of juvenile mojarra supplied with feed containing varying levels of crude protein

    Directory of Open Access Journals (Sweden)

    Ricardo Henrique Bastos de Souza

    2016-04-01

    Full Text Available ABSTRACT The growth of the Brazilian aquaculture has stimulated the development of the productive chain of native species, including marine environment. The objective of this study was to evaluate the growth performance of juvenile mojarra fish (Diapterus rhombeus fed diets containing different concentrations of crude protein (32, 36, 40 and 44 g 100 g-1. The 80 juvenile mojarra (7.2±1.5 g were kept in 16 circular tanks (150 L. The study design used was completely randomized with four treatments and four repetitions. The fish were fed four times a day. At the end of the experiment (60 days the final weight, feed intake, weight gain (WG, feed:gain ratio (FGR, protein efficiency rate (PER, energy efficiency rate, specific growth, survival rate and, body composition were evaluated. It was verified significant effect of protein level on the WG, with the best value at the level of 38.20 g 100 g-1 of crude protein. For FGR, the best estimated value occurred with 38.06 g 100 g-1 of crude protein, similar to that reported for the PER (38.91 g 100 g-1. The other performance parameters and body composition were not influenced by crude protein levels. Diet crude protein concentrations between 38.06 and 38.91 g 100 g-1 provide the best performance indices for juvenile mojarra.

  4. Current Monitoring System for ITER Like ICRH Antenna

    International Nuclear Information System (INIS)

    Argouarch, A.

    2006-01-01

    On TS antennas, the power transfer optimization from ICRH antenna to Plasma load is performed using feedback internal matching system. Experimental handling is required to mach the reactive impedance accordingly to the fluctuant plasma loading. As part of the development of the new ICRH prototype antenna, an additional measurement system based on Rogowski coils was developed to monitor the current distribution in antenna straps. The objective is to control module and phase of the antenna current straps with measurement provided by the coil system. Matching capacitors values, generators power and phase can also be controlled using the output of the devices, improving the real time matching control of the array. This paper details the new measurement layout, the Rogowski coil, and the whole system connected on each strap design for RF currents measurement between 40 MHz - 60 MHz for maximum amplitude of 1 kA. On the new ICRH prototype antenna, the measurement coils are coupled to the point where the strap currents are short circuited to the frame. The module and phase measurements are performed with the coils by direct magnetic induction in a vacuum and high temperature environment. Also, the Rogowski coils were characterized at low level power with vector network analyzer and the design adapted in order to obtain a controlled and reproducible gain in the desire bandwidth. The transconductive function is established with an experimental gain near -80 dB between primary circuit and inductive signal generated by the Rogowski coil. In a second step, the system with its associated electronic was qualified under high RF power. First results with high RF current (closed to 500 A at 57 MHz) match the desire Rogowski coil response. Compromises with electrical response at low power level and the coil under thermal/RF stresses were the most challenging part of the development. The overall response of the system and the current module/phase measurements are promising. A proper

  5. Independent and combined influence of neonatal and current body composition on academic performance in youth: The UP & DOWN Study.

    Science.gov (United States)

    Esteban-Cornejo, I; Tejero-González, C M; Castro-Piñero, J; Conde-Caveda, J; Cabanas-Sanchez, V; Sallis, J F; Veiga, Óscar L

    2015-06-01

    Unhealthy body composition is a cause for concern across the lifespan. The objective of this study was to examine the independent and combined associations between neonatal and current body composition with academic performance among youth. This cross-sectional study was conducted with a total of 1557 youth (745 girls) aged 10.4 ± 3.4 years. Birth weight and length at birth were self-reported. Current body composition was assessed by body mass index (BMI), waist circumference (WC) and percentage of body fat (BF%). Academic performance was assessed through schools records. Birth weight was related to all academic variables in boys, independent of potential confounders, including BMI; whereas WC, BMI and BF% were related to all academic performance indicators in both boys and girls, independent of potential confounders, including birth weight (all P academic performance were observed in both boys and girls for grade point average (GPA) indicator. Boys in the group with none adverse effect had significantly higher scores in GPA (score +0.535; 95% confidence interval, 0.082-0.989) than boys in the group of both adverse effects (P academic performance in youth. © 2014 The Authors. Pediatric Obesity © 2014 World Obesity.

  6. Low Voltage Current Mode Switched-Current-Mirror Mixer

    Directory of Open Access Journals (Sweden)

    Chunhua Wang

    2009-09-01

    Full Text Available A new CMOS active mixer topology can operate at 1 V supply voltage by use of SCM (switched currentmirror. Such current-mode mixer requires less voltage headroom with good linearization. Mixing is achieved with four improved current mirrors, which are alternatively activated. For ideal switching, the operation is equivalent to a conventional active mixer. This paper analyzes the performance of the SCM mixer, in comparison with the conventional mixer, demonstrating competitive performance at a lower supply voltage. Moreover, the new mixer’s die, without any passive components, is very small, and the conversion gain is easy to adjust. An experimental prototype was designed and simulated in standard chartered 0.18μm RF CMOS Process with Spectre in Cadence Design Systems. Experimental results show satisfactory mixer performance at 2.4 GHz.

  7. Monolithic quasi-sliding-mode controller for SIDO buck converter with a self-adaptive free-wheeling current level

    Science.gov (United States)

    Xiaobo, Wu; Qing, Liu; Menglian, Zhao; Mingyang, Chen

    2013-01-01

    An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output (SIDO) buck converter in pseudo-continuous conduction mode (PCCM) with a self-adaptive freewheeling current level (SFCL) is presented. Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter. Moreover, an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers. Instead of keeping it as a constant value, the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time. To verify the feasibility of the proposed controller, an SIDO buck converter with two regulated output voltages, 1.8 V and 3.3 V, is designed and fabricated in HEJIAN 0.35 μm CMOS process. Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 μs while the cross-regulation is reduced to 0.057 mV/mA, when its first load changes from 50 to 100 mA.

  8. Effects of heat and water transport on the performance of polymer electrolyte membrane fuel cell under high current density operation

    International Nuclear Information System (INIS)

    Tabuchi, Yuichiro; Shiomi, Takeshi; Aoki, Osamu; Kubo, Norio; Shinohara, Kazuhiko

    2010-01-01

    Key challenges to the acceptance of polymer electrolyte membrane fuel cells (PEMFCs) for automobiles are the cost reduction and improvement in its power density for compactness. In order to get the solution, the further improvement in a fuel cell performance is required. In particular, under higher current density operation, water and heat transport in PEMFCs has considerable effects on the cell performance. In this study, the impact of heat and water transport on the cell performance under high current density was investigated by experimental evaluation of liquid water distribution and numerical validation. Liquid water distribution in MEA between rib and channel area is evaluated by neutron radiography. In order to neglect the effect of liquid water in gas channels and reactant species concentration distribution in the flow direction, the differential cell was used in this study. Experimental results suggested that liquid water under the channel was dramatically changed with rib/channel width. From the numerical study, it is found that the change of liquid water distribution was significantly affected by temperature distribution in MEA between rib and channel area. In addition, not only heat transport but also water transport through the membrane also significantly affected the cell performance under high current density operation.

  9. Effect of dietary energy levels and phase feeding by protein levels on growth performance, blood profiles and carcass characteristics in growing-finishing pigs

    Directory of Open Access Journals (Sweden)

    J. S. Hong

    2016-10-01

    Full Text Available Abstract Background Providing of insufficient nutrients limits the potential growth of pig, while feeding of excessive nutrients increases the economic loss and causes environment pollution. For these reasons, phase feeding had been introduced in swine farm for improving animal production. This experiment was conducted to evaluate the effects of dietary energy levels and phase feeding by protein levels on growth performance, blood profiles and carcass characteristics in growing-finishing pigs. Methods A total of 128 growing pigs ([Yorkshire × Landrace] × Duroc, averaging 26.62 ± 3.07 kg body weight, were assigned in a 2 × 4 factorial arrangement with 4 pigs per pen. The first factor was two dietary energy level (3,265 kcal of ME/kg or 3,365 kcal of ME/kg, and the second factor was four different levels of dietary protein by phase feeding (1growing(G-2finishing(F phases, 2G-2F phases, 2G-3F phases and 2G-3F phases with low CP requirement. Results In feeding trial, there was no significant difference in growth performance. The BUN concentration was decreased as dietary protein level decreased in 6 week and blood creatinine was increased in 13 week when pigs were fed diets with different dietary energy level. The digestibility of crude fat was improved as dietary energy levels increased and excretion of urinary nitrogen was reduced when low protein diet was provided. Chemical compositions of longissimus muscle were not affected by dietary treatments. In backfat thickness (P2 at 13 week, pigs fed high energy diet had thicker backfat thickness (P = 0.06 and pigs fed low protein diet showed the trend of backfat thinness reduction (P = 0.09. In addition, water holding capacity was decreased (P = 0.01 and cooking loss was increased (P = 0.07 as dietary protein level reduced. When pigs were fed high energy diet with low subdivision of phase feeding, days to 120 kg market weight was reached earlier compared to

  10. Modular Software Performance Monitoring

    CERN Document Server

    Kruse, D F

    2011-01-01

    CPU clock frequency is not likely to be increased significantly in the coming years, and data analysis speed can be improved by using more processors or buying new machines, only if one is willing to change the paradigm to a parallel one. Therefore, performance monitoring procedures and tools are needed to help programmers to optimize existing software running on current and future hardware. Low level information from hardware performance counters is vital to spot specific performance problems slowing program execution. HEP software is often huge and complex, and existing tools are unable to give results with the required granularity. We will report on the approach we have chose to solve this problem that involves decomposing the application into parts and monitoring each of them separately. Both counting and sampling methods are used to allow an analysis with the required custom granularity: from global level, up to the function level. A set of tools (based on perfmon2 – a software interface to hardware co...

  11. Levels of Job Satisfaction and Performance of Sports Officers in Lagos State Secondary Schools

    Science.gov (United States)

    Onifade, Ademola; Keinde, Idou; Kehinde, Eunice

    2009-01-01

    The purpose of this paper was to examine the relationship between job satisfaction levels of sports officers and sports performance of secondary schools in Lagos State. Data were collected from 200 subjects across 10 Local Education Districts. Job Descriptive Index was used to determine job satisfaction while performance in the Principals' Soccer…

  12. Graphene-Armored Aluminum Foil with Enhanced Anticorrosion Performance as Current Collectors for Lithium-Ion Battery.

    Science.gov (United States)

    Wang, Mingzhan; Tang, Miao; Chen, Shulin; Ci, Haina; Wang, Kexin; Shi, Liurong; Lin, Li; Ren, Huaying; Shan, Jingyuan; Gao, Peng; Liu, Zhongfan; Peng, Hailin

    2017-12-01

    Aluminum (Al) foil, as the most accepted cathode current collector for lithium-ion batteries (LIBs), is susceptible to local anodic corrosions during long-term operations. Such corrosions could lead to the deterioration or even premature failure of the batteries and are generally believed to be a bottleneck for next-generation 5 V LIBs. Here, it is demonstrated that Al foil armored by conformal graphene coating exhibits significantly reinforced anodic corrosion resistance in both LiPF 6 and lithium bis(trifluoromethanesulphonyl) imide (LiTFSI) based electrolytes. Moreover, LiMn 2 O 4 cells using graphene-armored Al foil as current collectors (LMO/GA) demonstrate enhanced electrochemical performance in comparison with those using pristine Al foil (LMO/PA). The long-term discharge capacity retention of LMO/GA cell after ≈950 h straight operations at low rate (0.5 C) reaches up to 91%, remarkably superior to LMO/PA cell (75%). The self-discharge propensity of LMO/GA is clearly relieved and the rate/power performance is also improved with graphene mediations. This work not only contributes to the long-term stable operations of LIBs but also might catalyze the deployment of 5 V LIBs in the future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. The Solenarc circuit-breaker of high performance level

    International Nuclear Information System (INIS)

    Lehmann, J.M.

    1983-01-01

    After recalling the breaking principle involved in MV circuit-breakers manufactured by Merlin Gerin, it is showed how Solenarc technique enables specific problems to be solved that are set by the equipment of Eurodif plant at Tricastin and that represent constraints similar to those encountered with protective equipment for power station auxiliaries (high rated currents, long duration overloads, very high short-circuit currents, current breaks without natural passage through zero, etc.) [fr

  14. Current distribution inside Rutherford-type superconducting cables and impact on performance of LHC dipoles

    CERN Document Server

    Schreiner, T

    2002-01-01

    The windings of high--field superconducting accelerator magnets are usually made of Rutherford--type cables. The magnetic field distribution along the axis of such magnets exhibits a periodic modulation with a wavelength equal to the twist pitch length of the cable used in the winding. Such a Periodic Field Pattern (PFP) has already been observed in number of superconducting accelerator magnets. Additional unbalanced currents in individual strands of the cable appear to be causing this effect. The present thesis describes the investigation of the PFPs performed with a Hall probes array inserted inside the aperture of the LHC superconducting dipoles, both in the small--scale model magnets with a length of one meter and in full--scale prototypes and pre--series magnets with fifteen meters of length. The amplitude and the time dependence of this periodic field oscillation have been studied as a function of the magnet current history. One of the main parameters influencing the properties of the PFP is the cross--...

  15. Repository environmental parameters and models/methodologies relevant to assessing the performance of high-level waste packages in basalt, tuff, and salt

    Energy Technology Data Exchange (ETDEWEB)

    Claiborne, H.C.; Croff, A.G.; Griess, J.C.; Smith, F.J.

    1987-09-01

    This document provides specifications for models/methodologies that could be employed in determining postclosure repository environmental parameters relevant to the performance of high-level waste packages for the Basalt Waste Isolation Project (BWIP) at Richland, Washington, the tuff at Yucca Mountain by the Nevada Test Site, and the bedded salt in Deaf Smith County, Texas. Guidance is provided on the identify of the relevant repository environmental parameters; the models/methodologies employed to determine the parameters, and the input data base for the models/methodologies. Supporting studies included are an analysis of potential waste package failure modes leading to identification of the relevant repository environmental parameters, an evaluation of the credible range of the repository environmental parameters, and a summary of the review of existing models/methodologies currently employed in determining repository environmental parameters relevant to waste package performance. 327 refs., 26 figs., 19 tabs.

  16. Repository environmental parameters and models/methodologies relevant to assessing the performance of high-level waste packages in basalt, tuff, and salt

    International Nuclear Information System (INIS)

    Claiborne, H.C.; Croff, A.G.; Griess, J.C.; Smith, F.J.

    1987-09-01

    This document provides specifications for models/methodologies that could be employed in determining postclosure repository environmental parameters relevant to the performance of high-level waste packages for the Basalt Waste Isolation Project (BWIP) at Richland, Washington, the tuff at Yucca Mountain by the Nevada Test Site, and the bedded salt in Deaf Smith County, Texas. Guidance is provided on the identify of the relevant repository environmental parameters; the models/methodologies employed to determine the parameters, and the input data base for the models/methodologies. Supporting studies included are an analysis of potential waste package failure modes leading to identification of the relevant repository environmental parameters, an evaluation of the credible range of the repository environmental parameters, and a summary of the review of existing models/methodologies currently employed in determining repository environmental parameters relevant to waste package performance. 327 refs., 26 figs., 19 tabs

  17. PERFORMANCE MANAGEMENT AT THE ORGANIZATIONAL LEVEL

    Directory of Open Access Journals (Sweden)

    Nicola Terracciano

    2017-06-01

    Full Text Available Performance management is „a strategic and integrated approach to delivering sustained succes to organizations, by improving the performance of the people who working in them, and by developing the capabilities of teams and individual contributions” [1]. At the same time, it is a systematic approach of the human resource management, in general, and of the performance assessment, in particular, using goals, performance, appreciation and feedback as a means of motivating the employees to understand and to fully exploit their creative potential to achieve the organizational goals.   [1] Armstrong M. and  Baron D., Relating Competencies to Pay: The UK Experience, Compensation and Benefits Review, May-June, 1998, pp. 28 – 39;

  18. PERFORMANCE MANAGEMENT AT THE ORGANIZATIONAL LEVEL

    Directory of Open Access Journals (Sweden)

    Nicola Terracciano

    2017-07-01

    Full Text Available Performance management is „a strategic and integrated approach to delivering sustained succes to organizations, by improving the performance of the people who working in them, and by developing the capabilities of teams and individual contributions” [1]. At the same time, it is a systematic approach of the human resource management, in general, and of the performance assessment, in particular, using goals, performance, appreciation and feedback as a means of motivating the employees to understand and to fully exploit their creative potential to achieve the organizational goals. [1] Armstrong M. and Baron D., Relating Competencies to Pay: The UK Experience, Compensation and Benefits Review, May-June, 1998, pp. 28 – 39;

  19. Understanding the Relative Contributions of Lower-Level Word Processes, Higher-Level Processes, and Working Memory to Reading Comprehension Performance in Proficient Adult Readers

    Science.gov (United States)

    Hannon, Brenda

    2012-01-01

    Although a considerable amount of evidence has been amassed regarding the contributions of lower-level word processes, higher-level processes, and working memory to reading comprehension, little is known about the relationships among these sources of individual differences or their relative contributions to reading comprehension performance. This…

  20. Clinical Skills Performed By Iranian Emergency Nurses: Perceived Competency Levels and Attitudes Toward Expanding Professional Roles.

    Science.gov (United States)

    Hassankhani, Hadi; Hasanzadeh, Firooz; Powers, Kelly A; Dadash Zadeh, Abbas; Rajaie, Rouzbeh

    2018-03-01

    Emergency nurses play an important role in the care of critically ill and injured patients, and their competency to perform clinical skills is vital to safe and effective patient care. The aim of this study was to evaluate the frequency of clinical skills performed and perceived competency levels among Iranian emergency nurses. In addition, attitudes toward expanding the professional roles of Iranian emergency nurses were also assessed. In this descriptive correlational study, 319 emergency nurses from 30 hospitals in northwest Iran participated. Data were collected using a self-report questionnaire. Descriptive statistics and Pearson's correlation coefficient were used to present the findings. Overall competency of the emergency nurses was 73.31 ± 14.2, indicating a good level of perceived competence. The clinical skills most frequently performed were in the domains of organizational and workload competencies (3.43 ± 0.76), diagnostic function (3.25 ± 0.82), and the helping role (3.17 ± 0.83). A higher level of perceived competence was found for skills within these domains. Less frequently, participants performed skills within the domains of effective management of rapidly changing situations (2.70 ± 0.94) and administering and monitoring therapeutic interventions (2.60 ± 0.97); a lower perceived level of competence was noted for these clinical skills. There was a significant correlation between frequency of performing clinical skills and perceived competency level (r = 0.651, P skills. This has implications for nurse managers and educators who may consider offering more frequent experiential and educational opportunities to emergency nurses. Expansion of nurses' roles could also result in increased experience in clinical skills and higher levels of competency. Research is needed to investigate nurses' clinical competence using direct and observed measures. Copyright © 2017 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

  1. ATLAS High Level Calorimeter Trigger Software Performance for Cosmic Ray Events

    CERN Document Server

    Oliveira Damazio, Denis; The ATLAS collaboration

    2009-01-01

    The ATLAS detector is undergoing intense commissioning effort with cosmic rays preparing for the first LHC collisions next spring. Combined runs with all of the ATLAS subsystems are being taken in order to evaluate the detector performance. This is an unique opportunity also for the trigger system to be studied with different detector operation modes, such as different event rates and detector configuration. The ATLAS trigger starts with a hardware based system which tries to identify detector regions where interesting physics objects may be found (eg: large energy depositions in the calorimeter system). An approved event will be further processed by more complex software algorithms at the second level where detailed features are extracted (full detector granularity data for small portions of the detector is available). Events accepted at this level will be further processed at the so-called event filter level. Full detector data at full granularity is available for offline like processing with complete calib...

  2. The current impact of entry-level associate and baccalaureate degree education on the diversity of respiratory therapists.

    Science.gov (United States)

    Becker, Ellen A; Nguyen, Xuan T

    2014-12-01

    Transitioning from an associate degree to a baccalaureate degree for respiratory therapists has been suggested as a new entry-level educational standard. One potential risk for this change is that it may limit the diversity of potential applicants for entry-level education. A diverse workforce is important to achieve the goal of reducing healthcare disparities. This study evaluated characteristics of therapists who completed associate and baccalaureate degree entry-level education. A secondary analysis of data collected from the 2009 AARC Respiratory Therapist Human Resource Survey explored relationships between the choice of entry-level associate or baccalaureate education and variables of gender, race, salary, career advancement, and job satisfaction. There were no differences between therapists with entry-level associate and baccalaureate degrees in gender, race, number of additional healthcare credentials, numbers of life support credentials, wages, delivering respiratory care by protocol, and job satisfaction. There were significantly higher percentages of advanced academic degrees, desire to pursue a higher academic degree, registered respiratory therapist credentials, total National Board for Respiratory Care credentials, and leadership roles for therapists with baccalaureate entry-level degrees. Current entry-level associate and baccalaureate degree graduates have similar gender and race proportions. This finding challenges concerns that an entry-level baccalaureate degree would decrease the diversity of the respiratory therapist workforce. Copyright © 2014 by Daedalus Enterprises.

  3. Noise exposure levels for musicians during rehearsal and performance times.

    Science.gov (United States)

    McIlvaine, Devon; Stewart, Michael; Anderson, Robert

    2012-03-01

    The purpose of this study was to determine daily noise doses and 8-hour time weighted averages for rock band musicians, crew members, and spectators during a typical rehearsal and performance using both Occupational Safety and Health Administration (OSHA) and National Institute of Occupational Safety and Health (NIOSH) measurement criteria. Personal noise dosimetry was completed on five members of a rock band during one 2-hr rehearsal and one 4-hr performance. Time-weighted averages (TWA) and daily dose values were calculated using both OSHA and NIOSH criteria and compared to industry guidelines for enrollment in hearing conservation programs and the use of hearing protection devices. TWA values ranged from 84.3 to 90.4 dBA (OSHA) and from 90.0 to 96.4 dBA (NIOSH) during the rehearsal. The same values ranged from 91.0 to 99.7 dBA (OSHA) and 94.0 to 102.8 dBA (NIOSH) for the performance. During the rehearsal, daily noise doses ranged from 45.54% to 106.7% (OSHA) and from 317.74% to 1396.07% (NIOSH). During the performance, doses ranged from 114.66% to 382.49% (OSHA) and from 793.31% to 5970.15% (NIOSH). The musicians in this study were exposed to dangerously high levels of noise and should be enrolled in a hearing conservation programs. Hearing protection devices should be worn, especially during performances. The OSHA measurement criteria yielded values significantly more conservative than those produced by NIOSH criteria. Audiologists should counsel musician-patients about the hazards of excessive noise (music) exposure and how to protect their hearing.

  4. Design and evaluation of three-level composite filters obtained by optimizing a compromise average performance measure

    Science.gov (United States)

    Hendrix, Charles D.; Vijaya Kumar, B. V. K.

    1994-06-01

    Correlation filters with three transmittance levels (+1, 0, and -1) are of interest in optical pattern recognition because they can be implemented on available spatial light modulators and because the zero level allows us to include a region of support (ROS). The ROS can provide additional control over the filter's noise tolerance and peak sharpness. A new algorithm based on optimizing a compromise average performance measure (CAPM) is proposed for designing three-level composite filters. The performance of this algorithm is compared to other three-level composite filter designs using a common image database and using figures of merit such as the Fisher ratio, error rate, and light efficiency. It is shown that the CAPM algorithm yields better results.

  5. Acute Alcohol Intoxication: Differences in School Levels and Effects on Educational Performance

    Science.gov (United States)

    Van Hoof, Joris J.; Klerk, Frouktje Ade; Van der Lely, Nicolaas

    2018-01-01

    This study examines the effects of acute alcohol intoxication on adolescents' school performance. In the 2007-2015 period, 3,317 adolescents (ages 12 to 17 years) were treated for acute alcohol intoxication, and 37 adolescents were admitted to the hospital twice. Alcohol intoxication has an overrepresentation in "low" school levels. The…

  6. High performance liquid-level sensor based on mPOFBG for aircraft applications

    DEFF Research Database (Denmark)

    Marques, C. A. F.; Pospori, A.; Saez-Rodriguez, D.

    2015-01-01

    A high performance liquid-level sensor based on microstructured polymer optical fiber Bragg grating (mPOFBG) array sensors is reported in detail. The sensor sensitivity is found to be 98pm/cm of liquid, enhanced by more than a factor of 9 compared to a reported silica fiber-based sensor....

  7. The Effect of Exposure to High Noise Levels on the Performance and Rate of Error in Manual Activities.

    Science.gov (United States)

    Khajenasiri, Farahnaz; Zamanian, Alireza; Zamanian, Zahra

    2016-03-01

    Sound is among the significant environmental factors for people's health, and it has an important role in both physical and psychological injuries, and it also affects individuals' performance and productivity. The aim of this study was to determine the effect of exposure to high noise levels on the performance and rate of error in manual activities. This was an interventional study conducted on 50 students at Shiraz University of Medical Sciences (25 males and 25 females) in which each person was considered as its own control to assess the effect of noise on her or his performance at the sound levels of 70, 90, and 110 dB by using two factors of physical features and the creation of different conditions of sound source as well as applying the Two-Arm coordination Test. The data were analyzed using SPSS version 16. Repeated measurements were used to compare the length of performance as well as the errors measured in the test. Based on the results, we found a direct and significant association between the levels of sound and the length of performance. Moreover, the participant's performance was significantly different for different sound levels (at 110 dB as opposed to 70 and 90 dB, p < 0.05 and p < 0.001, respectively). This study found that a sound level of 110 dB had an important effect on the individuals' performances, i.e., the performances were decreased.

  8. Design of a high-temperature superconductor current lead for electric utility SMES

    International Nuclear Information System (INIS)

    Niemann, R.C.; Cha, Y.S.; Hull, J.R.; Rey, C.M.; Dixon, K.D.

    1995-01-01

    Current leads that rely on high-temperature superconductors (HTSs) to deliver power to devices operating at liquid helium temperature have the potential to reduce refrigeration requirements to levels significantly below those achievable with conventional leads. The design of HTS current leads suitable for use in near-term superconducting magnetic energy storage (SMES) is in progress. The SMES system has an 0.5 MWh energy capacity and a discharge power of 30 MW. Lead-design considerations include safety and reliability, electrical and thermal performance, structural integrity, manufacturability, and cost. Available details of the design, including materials, configuration, and performance predictions, are presented

  9. Thermally Stimulated Currents in Nanocrystalline Titania

    Directory of Open Access Journals (Sweden)

    Mara Bruzzi

    2018-01-01

    Full Text Available A thorough study on the distribution of defect-related active energy levels has been performed on nanocrystalline TiO2. Films have been deposited on thick-alumina printed circuit boards equipped with electrical contacts, heater and temperature sensors, to carry out a detailed thermally stimulated currents analysis on a wide temperature range (5–630 K, in view to evidence contributions from shallow to deep energy levels within the gap. Data have been processed by numerically modelling electrical transport. The model considers both free and hopping contribution to conduction, a density of states characterized by an exponential tail of localized states below the conduction band and the convolution of standard Thermally Stimulated Currents (TSC emissions with gaussian distributions to take into account the variability in energy due to local perturbations in the highly disordered network. Results show that in the low temperature range, up to 200 K, hopping within the exponential band tail represents the main contribution to electrical conduction. Above room temperature, electrical conduction is dominated by free carriers contribution and by emissions from deep energy levels, with a defect density ranging within 1014–1018 cm−3, associated with physio- and chemi-sorbed water vapour, OH groups and to oxygen vacancies.

  10. Multi-level mass store implementation

    International Nuclear Information System (INIS)

    Leighton, J.F.

    1977-12-01

    The National Magnetic Fusion Energy Center is currently installing a very large mass data storage system. The storage system will comprise three distinct levels: magnetic disk, a CDC 38500 Mass Storage Facility, and high density 10 1 / 2 -inch reel magnetic tape. The resulting storage facility will emphasize the best characteristics of each level while masking the weaker characteristics. The goal is to give the overall system the performance and reliability of a magnetic disk system, the capacity of the CDC 38500 system, and the off-line archival storage characteristic of magnetic tape. 2 figures

  11. Conceptual plan for closer integration of network- and project-level pavement management

    Science.gov (United States)

    1998-01-01

    This report presents an evaluation of current performance modeling concepts and a feasibility study of the possibility of integrating network- and project-level performance prediction. The widely differing modeling methods in use today are reviewed a...

  12. Effects of dietary protein level on nutrients digestibility and reproductive performance of female mink (Neovison vison during gestation

    Directory of Open Access Journals (Sweden)

    Qingkui Jiang

    2015-06-01

    Full Text Available The objective of this study was to determine whether nutrient digestibility and reproductive performance of pregnant mink (Neovison vison were affected by different dietary protein levels. One hundred and twenty female mink were randomly assigned to four groups, receiving diets of fresh material with different protein levels. The dietary protein levels, expressed as percentage of dry matter (DM, were 32, 36, 40 and 44% respectively. These values corresponded to average 320, 360, 400 and 440 g protein/kg DM, respectively. Results were as follows. All of crude protein digestibility, nitrogen (N intake, N retention increased along with dietary protein level increasing. Low protein level (32% significantly reduced the above indicators (P < 0.05. DM digestibility and ether extract digestibility were not affected by dietary protein level. Results of mated females, barren females, kids per litter, live born kids per mated female, birth survival rate, and birth weight showed that mink achieved optimal reproductive performance when dietary protein level was 36%. In conclusion, dietary protein was anticipated to significantly influence some nutrients' utilization. Adopting the appropriate dietary protein level allow better reproduction performance. The most preferable reproductive performance was achieved when diet contained 275.5 g digestible protein per kg DM for female mink in gestation.

  13. Factors affecting the variability in the observed levels of cadmium in blood and urine among former and current smokers aged 20-64 and ≥ 65years.

    Science.gov (United States)

    Jain, Ram B

    2017-03-01

    Data from National Health and Nutrition Examination Survey for 1999-2012 were used to evaluate factors that affect observed levels of blood cadmium (BCd) and urine cadmium (UCd) among former and current smokers aged 20-64 and ≥65 years. Adjusted levels (AGM) for BCd and UCd were higher among females as compared to males. The order of AGM for BCd by race/ethnicity for 20-64 years old was non-Hispanic white (NHW) non-Hispanic black (NHB) and NHW > NHB for ≥65 years old. The order of AGMs for UCd for 20-64-year-old current smokers was NHW > NHB and NHW > NHB for former smokers. For 20-64-year-old current smokers, exposure to environmental tobacco smoke at home was associated with higher levels of BCd. Levels of both UCd and BCd increased with age, but the rate of increase was as much as seven times higher among ≥65 years old than 20-64 years old. For current smokers, the number of cigarettes smoked inside home was positively associated with the levels of BCd. For current smokers aged 20-64 years, the number of cigarettes smoked inside home was positively associated with the levels of UCd (p smoked every day on the days they were smoked was also positively associated with the levels of UCd (p smokers, levels of both UCd and BCd were positively associated (p smoked per day at the time of quitting smoking and negatively associated with the time since smoking was quitted (p < 0.01).

  14. Performance analysis of Brazilian highways under concession through the capacity and level of service

    Energy Technology Data Exchange (ETDEWEB)

    Silveira Santos, T.; Martins Ribeiro, P.C.

    2016-07-01

    This paper proposes the development of a methodology to analyze the performance of highways under concession through the capacity and level of service, with special attention to Brazilian highways. The trajectory of transport infrastructure provision in Brazil and its performance assessment framework are mentioned, as well as an approach of the level of service concept and the Highway Capacity Manual (HCM). An inventory of the highway with the necessary data to the model is proposed. This database should incorporate information from multiple data sources and its use will be important for the processing and compilation of raw data in order to structure a full informational basis. Then, it is developed a method for segmentation of homogeneous road sections, as conceptualized by HCM, and proposed a way of level of service measurement. Finally, there are analysis of the use of HCM in some highways concession programs in Brazil. (Author)

  15. High performance yellow organic electroluminescent devices by doping iridium(III) complex into host materials with stepwise energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Rongzhen; Zhou, Liang, E-mail: zhoul@ciac.ac.cn; Jiang, Yunlong; Li, Yanan; Zhao, Xuesen; Zhang, Hongjie, E-mail: hongjie@ciac.ac.cn

    2015-10-15

    In this work, we aim to further improve the electroluminescent (EL) performances of a yellow light-emitting iridium(III) complex by designing double light-emitting layers (EMLs) devices having stepwise energy levels. Compared with single-EML devices, these designed double-EML devices showed improved EL efficiency and brightness attributed to better balance in carriers. In addition, the stepwise distribution in energy levels of host materials is instrumental in broadening the recombination zone, thus delaying the roll-off of EL efficiency. Based on the investigation of carriers' distribution, device structure was further optimized by adjusting the thickness of deposited layers. Finally, yellow EL device (Commission Internationale de l'Eclairage (CIE) coordinates of (0.446, 0.542)) with maximum current efficiency, power efficiency and brightness up to 78.62 cd/A (external quantum efficiency (EQE) of 21.1%), 82.28 lm/W and 72,713 cd/m{sup 2}, respectively, was obtained. Even at the high brightness of 1000 cd/m{sup 2}, EL efficiency as high as 65.54 cd/A (EQE=17.6%) can be retained. - Highlights: • Yellow electroluminescent devices were designed and fabricated. • P-type and n-type materials having stepwise energy levels were chosen as host materials. • Better balance of holes and electrons causes the enhanced efficiencies. • Improved carriers' trapping suppresses the emission of host material.

  16. Variable learning performance: the levels of behaviour organization.

    Science.gov (United States)

    Csányi, V; Altbäcker, V

    1990-01-01

    Our experiments were focused on some special aspects of learning in the paradise fish. Passive avoidance conditioning method was used with different success depending on the complexity of the learning tasks. In the case of simple behavioural elements various "constrains" on avoidance learning were found. In a small, covered place the fish were ready to perform freezing reaction and mild punishment increased the frequency and duration of the freezing bouts very substantially. However, it was very difficult to enhance the frequency of freezing by punishment in a tank with transparent walls, where the main response to punishment was escape. The most easily learned tasks were the complex ones which had several different solutions. The fish learned to avoid either side of an aquarium very easily because they could use various behavioural elements to solve the problem. These findings could be interpreted within the framework of different organizational levels of behaviour.

  17. Methodological approaches to the assessment level of social responsibility

    OpenAIRE

    Vorona, E.

    2010-01-01

    A study of current approaches to assessing the level of social responsibility. Proposed methodological approach to evaluating the performance of the social responsibility of railway transport. Conceptual Basis of social reporting in rail transport.

  18. Seismic Vulnerability and Performance Level of confined brick walls

    International Nuclear Information System (INIS)

    Ghalehnovi, M.; Rahdar, H. A.

    2008-01-01

    There has been an increase on the interest of Engineers and designers to use designing methods based on displacement and behavior (designing based on performance) Regarding to the importance of resisting structure design against dynamic loads such as earthquake, and inability to design according to prediction of nonlinear behavior element caused by nonlinear properties of constructional material.Economically speaking, easy carrying out and accessibility of masonry material have caused an enormous increase in masonry structures in villages, towns and cities. On the other hand, there is a necessity to study behavior and Seismic Vulnerability in these kinds of structures since Iran is located on the earthquake belt of Alpide.Different reasons such as environmental, economic, social, cultural and accessible constructional material have caused different kinds of constructional structures.In this study, some tied walls have been modeled with software and with relevant accelerator suitable with geology conditions under dynamic analysis to research on the Seismic Vulnerability and performance level of confined brick walls. Results from this analysis seem to be satisfactory after comparison of them with the values in Code ATC40, FEMA and standard 2800 of Iran

  19. Seismic Vulnerability and Performance Level of confined brick walls

    Science.gov (United States)

    Ghalehnovi, M.; Rahdar, H. A.

    2008-07-01

    There has been an increase on the interest of Engineers and designers to use designing methods based on displacement and behavior (designing based on performance) Regarding to the importance of resisting structure design against dynamic loads such as earthquake, and inability to design according to prediction of nonlinear behavior element caused by nonlinear properties of constructional material. Economically speaking, easy carrying out and accessibility of masonry material have caused an enormous increase in masonry structures in villages, towns and cities. On the other hand, there is a necessity to study behavior and Seismic Vulnerability in these kinds of structures since Iran is located on the earthquake belt of Alpide. Different reasons such as environmental, economic, social, cultural and accessible constructional material have caused different kinds of constructional structures. In this study, some tied walls have been modeled with software and with relevant accelerator suitable with geology conditions under dynamic analysis to research on the Seismic Vulnerability and performance level of confined brick walls. Results from this analysis seem to be satisfactory after comparison of them with the values in Code ATC40, FEMA and standard 2800 of Iran.

  20. Device and circuit-level performance of carbon nanotube field-effect transistor with benchmarking against a nano-MOSFET.

    Science.gov (United States)

    Tan, Michael Loong Peng; Lentaris, Georgios; Amaratunga Aj, Gehan

    2012-08-19

    The performance of a semiconducting carbon nanotube (CNT) is assessed and tabulated for parameters against those of a metal-oxide-semiconductor field-effect transistor (MOSFET). Both CNT and MOSFET models considered agree well with the trends in the available experimental data. The results obtained show that nanotubes can significantly reduce the drain-induced barrier lowering effect and subthreshold swing in silicon channel replacement while sustaining smaller channel area at higher current density. Performance metrics of both devices such as current drive strength, current on-off ratio (Ion/Ioff), energy-delay product, and power-delay product for logic gates, namely NAND and NOR, are presented. Design rules used for carbon nanotube field-effect transistors (CNTFETs) are compatible with the 45-nm MOSFET technology. The parasitics associated with interconnects are also incorporated in the model. Interconnects can affect the propagation delay in a CNTFET. Smaller length interconnects result in higher cutoff frequency.

  1. Performance Level Differences in Swimming: A Meta-Analysis of Passive Drag Force

    Science.gov (United States)

    Havriluk, Rod

    2005-01-01

    The streamline is a basic position for competitive swimming starts mid turns and has been used in many studies on resistive forces. However, there is a wide yahweh, of theoretical interpretations in these studies, leading to diverse and questionable conclusions. The purpose of this study was to determine performance level differences in the…

  2. The Effects of Blood Glucose Levels on Cognitive Performance: A Review of the Literature

    Science.gov (United States)

    Feldman, Jolene; Barshi, Immanuel

    2007-01-01

    The purpose of this review paper is to discuss the research literature on the effects of blood glucose levels on executive and non-executive functions in humans. The review begins with a brief description of blood glucose, how it has been studied, previous syntheses of prior studies, and basic results regarding the role of blood glucose on cognitive functioning. The following sections describe work that investigated the effect of blood glucose on both non-executive and executive functions (e.g., sensory processing, psychomotor functioning, attention, vigilance, memory, language and communication, judgement and decision-making, and complex task performance). Within each section, summaries of the findings and challenges to the literature are included. Measurement conversions of blood glucose levels, blood glucose values, and associated symptoms are depicted. References to the types of tests used to investigate blood glucose and cognitive performance are provided. For more detailed descriptions of references within (and in addition to) this paper, an annotated bibliography is also provided. Several moderator variables including individual differences and contextual variables related to the effects of blood glucose levels on performance (e.g., age, gender, time of day, familiarity with the task and symptom awareness, expectancy effects, dose dependent effects, time dependent effects, task specific effects, rising and falling blood glucose levels, and speed and/or accuracy trade-offs) are addressed later in the paper. Some suggestions for future experimental methodologies are also made.

  3. The role of incline, performance level and gender on the gross mechanical efficiency of roller ski skating

    Directory of Open Access Journals (Sweden)

    Øyvind eSandbakk

    2013-10-01

    Full Text Available The ability to efficiently utilize metabolic energy to produce work is a key factor for endurance performance. The present study investigated the effects of incline, performance level and gender on the gross mechanical efficiency during roller ski skating. Thirty-one male and nineteen female elite cross-country skiers performed a 5-min submaximal session at approximately 75% of VO2peak on a 5% inclined treadmill using the G3 skating technique. Thereafter, a 5-min session on a 12% incline using the G2 skating technique was performed at a similar work rate. Gross efficiency was calculated as the external work rate against rolling friction and gravity divided by the metabolic rate using gas exchange. Performance level was determined by the amount of skating FIS points (the Federation of International Skiing approved scoring system for ski racing where fewer points indicate a higher performance level. Strong significant correlations between work rate and metabolic rate within both inclines and gender were revealed (r=-0.89-0.98 and P

  4. Effect of Different Levels of Extruded Soybean and Avizyme Enzyme on Broiler Performance

    Directory of Open Access Journals (Sweden)

    H Nasiri Mogadam

    2012-01-01

    Full Text Available An experiment was conducted to examine the effect of different levels of extruded soybean and enzyme on broiler performance. In a completely randomized design with 2×3 factorial arrangement, 480 one day-old, Ross broiler chickens were divided into 40 groups, 12 chicks per pen. Treatments were consisting of combination of four levels of extruded soybean (0.0, 5.0, 10.0 and 15.0 % and two levels of enzyme (0.0 and 500 g per ton. Different levels of extruded soybean and enzyme had no significant effect on blood factors such as cholesterol, triglyceride and the weight of liver and heart. The usage of extruded soybean and enzyme showed significantly higher weight gain and better feed conversion (p

  5. Milking performance evaluation and factors affecting milking claw vacuum levels with flow simulator.

    Science.gov (United States)

    Enokidani, Masafumi; Kawai, Kazuhiro; Shinozuka, Yasunori; Watanabe, Aiko

    2017-08-01

    Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high-producing cows. This study used a simulated milking device to examine the milking performance of the milking system of 73 dairy farms and to analyze the factors affecting claw vacuum. Mean claw vacuum and range of fluctuation of claw vacuum (claw vacuum range) were measured at three different flow rates: 5.7, 7.6 and 8.7 kg/min. At the highest flow rate, only 16 farms (21.9%) met both standards of mean claw vacuum ≥35 kPa and claw vacuum range ≤ 7 kPa, showing that milking systems currently have poor milking performance. The factors affecting mean claw vacuum were claw type, milk-meter and vacuum shut-off device; the factor affecting claw vacuum range was claw type. Examination of the milking performance of the milking system using a simulated milking device allows an examination of the performance that can cope with high producing cows, indicating the possibility of reducing the risk of mastitis caused by inappropriate claw vacuum. © 2016 Japanese Society of Animal Science.

  6. Comparison radiation dose of Z-axis automatic tube current modulation technique with fixed tube current multi-detector row CT scanning of lower extremity venography

    International Nuclear Information System (INIS)

    Yoo, Beong Gyu; Kweon, Dae Cheol; Lee, Jong Seok; Jang, Keun Jo; Jeon, Sang Hwan; Kim, Yong Soo

    2007-01-01

    Z-axis automatic tube current modulation technique automatically adjusts tube current based on size of body region scanned. The purpose of the current study was to compare noise, and radiation dose of Multi-Detector row CT (MDCT) of lower extremity performed with Z-axis modulation technique of automatic tube current modulation with manual selection fixed tube current. Fifty consecutive underwent MDCT venography of lower extremity with use of a MDCT scanner fixed tube current and Z-axis automatic tube current modulation technique (10, 11 and 12 HU noise index, 70∼450 mA). Scanning parameters included 120 kVp, 0.5 second gantry rotation time, 1.35:1 beam pitch, and 1 mm reconstructed section thickness. For each subject, images obtained with Z-axis modulation were compared with previous images obtained with fixed tube current (200, 250, 300 mA) and with other parameters identical. Images were compared for noise at five levels: iliac, femoral, popliteal, tibial, and peroneal vein of lower extremity. Tube current and gantry rotation time used for acquisitions at these levels were recorded. All CT examinations of study and control groups were diagnostically acceptable, though objective noise was significantly more with Z-axis automatic tube current modulation. Compared with fixed tube current, Z-axis modulation resulted in reduction of CTDIvol (range, -6.5%∼-35.6%) and DLP (range,-0.2%∼-20.2%). Compared with manually selected fixed tube current, Z-axis automatic tube current modulation resulted in reduced radiation dose at MDCT of lower extremity venography

  7. Parameter design and performance simulation of a 10 kV voltage compensation type active superconducting fault current limiter

    International Nuclear Information System (INIS)

    Chen, L.; Tang, Y.J.; Song, M.; Shi, J.; Ren, L.

    2013-01-01

    Highlights: •For a practical 10 kV system, the 10 kV active SFCL’s basic parameters are designed. •Under different fault conditions, the 10 kV active SFCL’s performances are simulated. •The designed 10 kV active SFCL’s engineering feasibility is discussed preliminarily. -- Abstract: Since the introduction of superconducting fault current limiter (SFCL) into electrical distribution system may be a good choice with economy and practicability, the parameter design and current-limiting characteristics of a 10 kV voltage compensation type active SFCL are studied in this paper. Firstly, the SFCL’s circuit structure and operation principle are presented. Then, taking a practical 10 kV distribution system as its application object, the SFCL’s basic parameters are designed to meet the system requirements. Further, using MATLAB, the detailed current-limiting performances of the 10 kV active SFCL are simulated under different fault conditions. The simulation results show that the active SFCL can deal well with the faults, and the parameter design’s suitability can be testified. At the end, in view of the engineering feasibility of the 10 kV active SFCL, some preliminary discussions are carried out

  8. Knowledge Tracing and Prediction of Future Trainee Performance

    National Research Council Canada - National Science Library

    Jastrzembski, Tiffany S; Gluck, Kevin A; Gunzelmann, Glenn

    2006-01-01

    ...). This model represents the system's estimate of the student's current knowledge or skill level, established from a performance history. Knowledge tracing (Aleven & Koedinger, 2002; Anderson, Conrad, & Corbett, 1989...

  9. Cernavoda NPP Unit 1: Operating experience program and plant specific performance indicators (level 2)

    International Nuclear Information System (INIS)

    Teodor, Vasile; Popa, Viorel

    1998-01-01

    The basis for the Operating Experience Program was set in place since early stages of the commissioning phase (1993), when a system based on the Canadian approach was implemented for reporting, reviewing, assessing and establishing of the necessary corrective action for unplanned events. This system provided excellent opportunity to train staff in unplanned event assessment methodology, and prepare the station for the formal reporting process following criticality in accordance with the licensing requirements. The formal process, set in place after criticality is described in Station Instruction Procedure SI-01365-P13 'Unplanned Event Report' and was developed under the supervision of Safety and Compliance Department. In parallel, a program for information exchange and trending of performance indicators was developed by Technical Services Department. The WANO recommendations following August 1997 Peer Review provided the opportunity for a better understanding and reconsideration of the Operating Experience Program. As a result, all the activities related to this topic were assigned to a new structure, within Safety and Compliance Department. As such an Operating Experience Group was created and a new program is now being developed in an integrated and centralized manner. The content of the paper is the following: - Overview; - Operating Experience Program; - Event Analysis (Unplanned Events Assessment System - UEIR Process- and Systematic Analysis of Operational Events - ACR Process); - Information Exchange Program; - Monitoring of Operating Experience - Plant Specific Performance Indicators; - Purpose; - Level 2 Performance Indicators. Four appendices are added containing: - A. Station performance indicators/targets (Level 2); - B. SPI (Station Performance Indicators - Level 2) - Graphics; - C. UEIR, LRS (Safety and Licensing Review Sheet), UEFR (Unplanned Event Follow-up Report), ACR and OPEX forms. (authors)

  10. The current role of simulators for performance evaluations and licensing (case of Mexico)

    International Nuclear Information System (INIS)

    Maldonado A, H.

    1997-01-01

    The main purpose of this paper is to share the experience acquired by the National Commission of Nuclear Safety and Safeguards (CNSNS) during the administration of both certification and licensing operational exams applied to Senior Reactor Operators (SRO) and Reactor OPerators (RO) by using a full-scope simulator. The licensing operational exams are administered to examinate candidates for a SRO or RO license while the certification operational exams are administered to all personnel that possess a SRO or RO license in order to renew their licenses within a six years period. A general description with the most important simulator antecedents from the initial authorization for its usage to provide the ''Initial Simulator Training Course'' until currently in which it has been started the installation and testing performance of a new computer equipment that will improve and increase the simulation capacity of the Laguna Verde Nuclear Power Plant (LVNPP) simulator. In other hand, it is showed the process that the CNSNS will apply during the next verification of the simulator certification which should be performed due to the old computer equipment is being replaced with a more modern computer equipment so that the simulation capability will be improved. The verification process was discussed with the utility personnel and as result of this an agreement has been established to carry into effect this hard task. Finally, the conclusions and recommendations from regulators point of view are presented regarding to the importance of perform a well both evaluation and verification of simulators performance. (author)

  11. Performance Evaluation of Electronic Inductor-Based Adjustable Speed Drives with Respect to Line Current Interharmonics

    DEFF Research Database (Denmark)

    Soltani, Hamid; Davari, Pooya; Blaabjerg, Frede

    2017-01-01

    Electronic Inductor (EI)-based front-end rectifiers have a large potential to become the prominent next generation of Active Front End (AFE) topology used in many applications including Adjustable Speed Drives (ASDs) for systems having unidirectional power flow. The EI-based ASD is mostly...... attractive due to its improved harmonic performance compared to a conventional ASD. In this digest, the input currents of the EI-based ASD are investigated and compared with the conventional ASDs with respect to interharmonics, which is an emerging power quality topic. First, the main causes...... of the interharmonic distortions in the ASD applications are analyzed under balanced and unbalanced load conditions. Thereafter, the key role of the EI at the DC stage is investigated in terms of high impedance and current harmonics transfer. Obtained experiments and simulations for both EI-based and conventional ASD...

  12. Environmental Management Performance Report

    International Nuclear Information System (INIS)

    EDER, D.M.

    2002-01-01

    The purpose of this report is to provide the Department of Energy Richland Operations Office (RL) a monthly summary of the Central Plateau Contractor's Environmental Management (EM) performance by Fluor Hanford (FH) and its subcontractors. Only current FH workscope responsibilities are described and other contractor/RL managed work is excluded. Please refer to other sections (BHI, PNNL) for other contractor information. Section A, Executive Summary, provides an executive level summary of the cost, schedule, and technical performance described in this report. It summarizes performance for the period covered, highlights areas worthy of management attention, and provides a forward look to some of the upcoming key performance activities as extracted from the contractor baseline. The remaining sections provide detailed performance data relative to each individual subproject (e.g., Plutonium Finishing Plant, Spent Nuclear Fuels, etc.), in support of Section A of the report. All information is updated as of January 31, 2002 unless otherwise noted. ''Stoplight'' boxes are used to indicate at a glance the condition of a particular safety area. Green boxes denote either (1) the data are stable at a level representing ''acceptable'' performance, or (2) an improving trend exists. Yellows denote the data are stable at a level from which improvement is needed. Red denotes a trend exists in a non-improving direction

  13. Current and Voltage Mode Multiphase Sinusoidal Oscillators Using CBTAs

    Directory of Open Access Journals (Sweden)

    M. Sagbas

    2013-04-01

    Full Text Available Current-mode (CM and voltage-mode (VM multiphase sinusoidal oscillator (MSO structures using current backward transconductance amplifier (CBTA are proposed. The proposed oscillators can generate n current or voltage signals (n being even or odd equally spaced in phase. n+1 CBTAs, n grounded capacitors and a grounded resistor are used for nth-state oscillator. The oscillation frequency can be independently controlled through transconductance (gm of the CBTAs which are adjustable via their bias currents. The effects caused by the non-ideality of the CBTA on the oscillation frequency and condition have been analyzed. The performance of the proposed circuits is demonstrated on third-stage and fifth-stage MSOs by using PSPICE simulations based on the 0.25 µm TSMC level-7 CMOS technology parameters.

  14. Study of current and planned high occupancy vehicle lane use: performance and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, F.; Westbrook, F.

    1985-12-01

    This report details the results of a nationwide study of HOV lanes: their characteristics and performance as traffic congestion mitigating and rideshare enhancing facilities. The study took the form of telephone interviews with a variety of planning agencies in each of the 48 contiguous states and Hawaii over the period April through June 1985, with subsequent receipt of the most current documentation on regional HOV lane operations. The most up-to-date evidence on each lane's performance is presented: its hourly and peak period person throughput vis-a-vis the highway's adjacent, conventional mixed traffic lane(s), its vehicle throughput and occupancy, travel speed and travel time savings for HOVs, lane rule violation rates, lane construction and maintenance costs and accident data. Estimates are provided of the growth in ridesharing over the life of the HOV-only lanes, of the number of vehicles removed from the highway through ridesharing, and of the subsequent fuel savings attributable to HOV lane projects. The relationship between bus patronage and carpool/vanpool mode adoption is looked at, and it is concluded that both forms of HOV can do well on properly planned lanes. The authors also point out the very partial nature of the existing evidence upon which to base HOV lane project evaluation, and the subsequent difficulty associated with ''selling'' the HOV lane concept to many planners and members of the public. They identify those characteristics associated with clearly successful HOV lane projects. Finally, the current state of planning for new HOV lanes in cities around the nation is described, and the major reasons given for rejection or abandonment of HOV lane projects are discussed.

  15. Performance measures for public transit mobility management.

    Science.gov (United States)

    2011-12-01

    "Mobility management is an innovative approach for managing and delivering coordinated public : transportation services that embraces the full family of public transit options. At a national level, there are : currently no industry recognized perform...

  16. Self-regulation and performance level of elite and non-elite youth soccer players

    NARCIS (Netherlands)

    Toering, T. T.; Elferink-Gemser, M. T.; Jordet, G.; Visscher, C.

    2009-01-01

    In learning and development, self-regulation can be described as the extent to which individuals are metacognitively, motivationally, and behaviourally proactive participants in their learning process (Zimmerman, 1989, 2006). We examined the relationship between self-regulation and performance level

  17. A monitoring tool for performance improvement in plastic surgery at the individual level.

    Science.gov (United States)

    Maruthappu, Mahiben; Duclos, Antoine; Orgill, Dennis; Carty, Matthew J

    2013-05-01

    The assessment of performance in surgery is expanding significantly. Application of relevant frameworks to plastic surgery, however, has been limited. In this article, the authors present two robust graphic tools commonly used in other industries that may serve to monitor individual surgeon operative time while factoring in patient- and surgeon-specific elements. The authors reviewed performance data from all bilateral reduction mammaplasties performed at their institution by eight surgeons between 1995 and 2010. Operative time was used as a proxy for performance. Cumulative sum charts and exponentially weighted moving average charts were generated using a train-test analytic approach, and used to monitor surgical performance. Charts mapped crude, patient case-mix-adjusted, and case-mix and surgical-experience-adjusted performance. Operative time was found to decline from 182 minutes to 118 minutes with surgical experience (p factors is essential for correct interpretation of performance in plastic surgery at the individual surgeon level. Cumulative sum and exponentially weighted moving average charts represent accurate methods of monitoring operative time to control and potentially improve surgeon performance over the course of a career.

  18. Resident self-other assessor agreement: influence of assessor, competency, and performance level.

    Science.gov (United States)

    Lipsett, Pamela A; Harris, Ilene; Downing, Steven

    2011-08-01

    To review the literature on self-assessment in the context of resident performance and to determine the correlation between self-assessment across competencies in high- and low-performing residents and assessments performed by raters from a variety of professional roles (peers, nurses, and faculty). Retrospective analysis of prospectively collected anonymous self-assessment and multiprofessional (360) performance assessments by competency and overall. University-based academic general surgical program. Sixty-two residents rotating in general surgery. Mean difference for each self-assessment dyad (self-peer, self-nurse, and self-attending physician) by resident performance quartile, adjusted for measurement error, correlation coefficients, and summed differences across all competencies. Irrespective of self-other dyad, residents asked to rate their global performance overestimated their skills. Residents in the upper quartile underestimated their specific skills while those in the lowest-performing quartile overestimated their abilities when compared with faculty, peers, and especially nurse raters. Moreover, overestimation was greatest in competencies related to interpersonal skills, communication, teamwork, and professionalism. Rater, level of performance, and the competency being assessed all influence the comparison of the resident's self-assessment and those of other raters. Self-assessment of competencies related to behavior may be inaccurate when compared with raters from various professions. Residents in the lowest-performing quartile are least able to identify their weakness. These data have important implications for residents, program directors, and the public and suggest that strategies that help the lowest-performing residents recognize areas in need of improvement are needed.

  19. DOE's performance evaluation project for mixed low-level waste disposal

    International Nuclear Information System (INIS)

    Waters, R.D.; Chu, M.S.Y.; Gruebel, M.M.; Lee, D.W.

    1995-01-01

    A performance evaluation (PE) is an analysis that estimates radionuclide concentration limits for 16 potential Department of Energy (DOE) mixed low-level waste (ULLW) disposal sites based on the analysis of two environmental exposure pathways (air and water) to an off-site individual and an inadvertent-intruder exposure pathway. Sites are analyzed for their ability to attenuate concentrations of specific radionuclides that could be released from wastes in a hypothetical ULLW disposal facility. Site-specific data and knowledge are used within a generic framework that is consistent across all sites being evaluated. After estimates of waste concentrations for the three pathways are calculated, the minimum of the waste concentration values is selected as the permissible waste concentration for each radionuclide. The PE results will be used as input to the process for DOE's ULLW disposal configuration. Preliminary comparisons of results from the PE and site-specific performance assessments indicate that the simple PE results generally agree with results of the performance assessments, even when site conditions are complex. This agreement with performance-assessment results increases confidence that similar results can be obtained at other sites that have good characterization data. In addition, the simple analyses contained in the PE illustrate a potential method to satisfy the needs of many regulators and the general public for a simple, conservative, defensible, and easily understandable analysis that provides results similar to those of more complex analyses

  20. Assessment of basic physical parameters of current Canadian-American National Hockey League (NHL ice hockey players

    Directory of Open Access Journals (Sweden)

    Martin Sigmund

    2016-03-01

    Full Text Available Background: Physical parameters represent an important part of the structure of sports performance and significantly contribute to the overall performance of an ice hockey player. Basic physical parameters are also an essential part of a comprehensive player assessment both during the initial NHL draft and further stages of a professional career. For an objective assessment it is desirable to know the current condition of development of monitored somatic parameters with regard to the sports discipline, performance level and gaming position. Objective: The aim of this study was to analyze and present the level of development of basic physical characteristics [Body Height (BH and Body Weight (BW] in current ice hockey players in the Canadian-American NHL, also with respect to various gaming positions. Another aim is to compare the results with relevant data of elite ice hockey players around the world. Methods: The data of 751 ice hockey players (age range: 18-43 years; 100% male from NHL (2014/2015 season are analyzed (goalkeepers, n = 67; defenders, n = 237; forwards, n = 447. Statistical data processing was performed using a single factor ANOVA and Fisher's (LSD post hoc test. The level of statistical significance was tested at a level of p ≤ .05; p ≤ .01. Effect size was expressed according to Cohen's d. Results: Current levels of monitored parameters of NHL players represent the values: BH = 186.0 ± 5.3 cm, BW = 91.7 ± 6.9 kg. Significant differences among positions were found for the BH (goalkeepers > defenders > forwards and BW (defenders > goalkeepers > forwards. Differences among forwards positions were also found for the BH (left wings > right wings > centers and BW (left wings > right wings > centers. Conclusion: The observed values represent the current level of basic physical parameters in professional ice hockey players in the NHL and can be considered

  1. Optimization of Temperature Level to Enhance Worker Performance in Automotive Industry

    OpenAIRE

    A. R. Ismail; M. Y.M. Yusof; N. K. Makhtar; B. M. Deros; M. R.A. Rani

    2010-01-01

    Problem statement: Production of automotive parts is among the largest contributor to economic earnings in Malaysia. The dominant work involve in producing automotive part were manual assembly process. Where it is definitely used a manpower capability. Thus the quality of the product heavily depends on workers comfort in the working condition. Temperature is one of the environmental factors that give significant effect on the worker performance. Approach: Temperature level and productivity ra...

  2. Recalled peer relationship experiences and current levels of self-criticism and self-reassurance.

    Science.gov (United States)

    Kopala-Sibley, Daniel C; Zuroff, David C; Leybman, Michelle J; Hope, Nora

    2013-03-01

    Numerous studies have shown that personality factors may increase or decrease individuals' vulnerability to depression, but little research has examined the role of peer relationships in the development of these factors. Accordingly, this study examined the role of recalled parenting and peer experiences in the development of self-criticism and self-reassurance. It was hypothesized that, controlling for recalled parenting behaviours, specific recalled experiences of peer relationships would be related to current levels of specific forms of self-criticism and self-reassurance. Hypotheses were tested using a retrospective design in which participants were asked to recall experiences of parenting and peer relationships during early adolescence. This age was chosen as early adolescence has been shown to be a critical time for the development of vulnerability to depression. A total of 103 female and 97 male young adults completed measures of recalled parenting, overt and relational victimization and prosocial behaviour by peers, and current levels of self-criticism and self-reassurance. Hierarchical regression analyses showed that parents and peers independently contributed to the development of self-criticism and self-reassurance. Specifically, controlling for parental care and control, overt victimization predicted self-hating self-criticism, relational victimization predicted inadequacy self-criticism, and prosocial behaviour predicted self-reassurance. As well, prosocial behaviour buffered the effect of overt victimization on self-reassurance. Findings highlight the importance of peers in the development of personality risk and resiliency factors for depression, and suggest avenues for interventions to prevent the development of depressive vulnerabilities in youth. The nature of a patient's personality vulnerability to depression may be better understood through a consideration of the patient's relationships with their peers as well as with parents during

  3. Monolithic quasi-sliding-mode controller for SIDO buck converter with a self-adaptive free-wheeling current level

    International Nuclear Information System (INIS)

    Wu Xiaobo; Liu Qing; Zhao Menglian; Chen Mingyang

    2013-01-01

    An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output (SIDO) buck converter in pseudo-continuous conduction mode (PCCM) with a self-adaptive freewheeling current level (SFCL) is presented. Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter. Moreover, an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers. Instead of keeping it as a constant value, the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time. To verify the feasibility of the proposed controller, an SIDO buck converter with two regulated output voltages, 1.8 V and 3.3 V, is designed and fabricated in HEJIAN 0.35 μm CMOS process. Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 μs while the cross-regulation is reduced to 0.057 mV/mA, when its first load changes from 50 to 100 mA. (semiconductor integrated circuits)

  4. Physical activity level in people with age related white matter changes correlates to better motor performance, lower comorbidity and higher cognitive level.

    Science.gov (United States)

    Pettersson, Anna F; Wahlund, Lars-Olof; Bronge, Lena; Olsson, Elisabeth; Amberla, Kaarina; Baezner, Hansjoerg; Crisby, Milita

    2017-07-12

    Physical activity plays a pivotal role in the development of disability and may modify the negative effect of vascular risk factors on progression of both cardio and cerebrovascular disorders. The aim of this study was to evaluate the activity level in people with age-related white matter changes as identified on magnetic resonance imaging (MRI) in relation to motor performance, cognition and perceived health. Data came from the first year follow up of one participating centers of the LADIS study. Fifty one subjects were first enrolled in the study. Complete first year follow up data was available for 41 subjects. Information on comorbidity, physical activity level, physical function, cognition, level of white matter changes and perceived health was collected. Physical activity level was classified with a yes or no question and with the Frenchay Activities Index (FAI). Only 36% of the subjects in this study were physically active according to the yes/no question. 27.5% of the subjects were active according to the FAI score which evaluates the everyday activities. Being active discriminated subjects with better physical function. Subjects active according to the FAI score had a higher cognitive level (p ≤ 0.01), lower comorbidity (p = 0.02) and performed better on all motor function tasks as assessed by walking speed (p ≤ 0.01) and the Short Physical Performance battery (SPPB) (p ≤ 0.01). Being physically active seems to be a long term protective factor. In our study, the majority of subjects with Age Related White Mattter Changes (ARWMC) with no or mild Instrumental Activity of Daily Living (IADL) disability did not attain recommended level of activity at first year follow up. Whether or not increasing physical activity may slow down cognitive decline and lessen development of disability in physically inactive subjects with manifest ARWC remains to be studied. not applicable.

  5. The Effects of Level of Training on Employee Perceived Empowerment, Commitment and Job Performance

    National Research Council Canada - National Science Library

    Backeberg, Pamela

    2001-01-01

    .... The purpose of this study was to determine the effects of level of training on employees' perceived psychological empowerment, commitment, and resultant job performance within the hospitality industry...

  6. Scheduler-dependent inter-cell interference and its impact on LTE uplink performance at flow level

    NARCIS (Netherlands)

    Dimitrova, D.C.; Heijenk, G.; Berg, J.L. van den; Yankov, S.

    2011-01-01

    The Long Term Evolution (LTE) cellular technology is expected to extend the capacity and improve the performance of current 3G cellular networks. Among the key mechanisms in LTE responsible for traffic management is the packet scheduler, which handles the allocation of resources to active flows in

  7. Spinal cord injury below-level neuropathic pain relief with dorsal root entry zone microcoagulation performed caudal to level of complete spinal cord transection.

    Science.gov (United States)

    Falci, Scott; Indeck, Charlotte; Barnkow, Dave

    2018-06-01

    OBJECTIVE Surgically created lesions of the spinal cord dorsal root entry zone (DREZ) to relieve central pain after spinal cord injury (SCI) have historically been performed at and cephalad to, but not below, the level of SCI. This study was initiated to investigate the validity of 3 proposed concepts regarding the DREZ in SCI central pain: 1) The spinal cord DREZ caudal to the level of SCI can be a primary generator of SCI below-level central pain. 2) Neuronal transmission from a DREZ that generates SCI below-level central pain to brain pain centers can be primarily through sympathetic nervous system (SNS) pathways. 3) Perceived SCI below-level central pain follows a unique somatotopic map of DREZ pain-generators. METHODS Three unique patients with both intractable SCI below-level central pain and complete spinal cord transection at the level of SCI were identified. All 3 patients had previously undergone surgical intervention to their spinal cords-only cephalad to the level of spinal cord transection-with either DREZ microcoagulation or cyst shunting, in failed attempts to relieve their SCI below-level central pain. Subsequent to these surgeries, DREZ lesioning of the spinal cord solely caudal to the level of complete spinal cord transection was performed using electrical intramedullary guidance. The follow-up period ranged from 1 1/2 to 11 years. RESULTS All 3 patients in this study had complete or near-complete relief of all below-level neuropathic pain. The analyzed electrical data confirmed and enhanced a previously proposed somatotopic map of SCI below-level DREZ pain generators. CONCLUSIONS The results of this study support the following hypotheses. 1) The spinal cord DREZ caudal to the level of SCI can be a primary generator of SCI below-level central pain. 2) Neuronal transmission from a DREZ that generates SCI below-level central pain to brain pain centers can be primarily through SNS pathways. 3) Perceived SCI below-level central pain follows a unique

  8. Comparison Criteria and Performance Levels for Soundproofing Panels Made in Different Constructive Variants

    Directory of Open Access Journals (Sweden)

    Ana Gheorghe

    2013-09-01

    Full Text Available This paper presents an analysis of the performance lavels and comparison criteria for panels made from different soundproofing materials, in different constructive variants. Setting the performance level, on the basis of normative and regulatory documents, for soundproofing materials contained inside of noise reduction devices, is determined so that it can be defined, tested and established feasible technical solutions for sound absorbing protection, through a dissemination of obtained results as well for ensuring requirements for implementing the technology transfer for manufacturing.

  9. Using satellite observations in performance evaluation for regulatory air quality modeling: Comparison with ground-level measurements

    Science.gov (United States)

    Odman, M. T.; Hu, Y.; Russell, A.; Chai, T.; Lee, P.; Shankar, U.; Boylan, J.

    2012-12-01

    Regulatory air quality modeling, such as State Implementation Plan (SIP) modeling, requires that model performance meets recommended criteria in the base-year simulations using period-specific, estimated emissions. The goal of the performance evaluation is to assure that the base-year modeling accurately captures the observed chemical reality of the lower troposphere. Any significant deficiencies found in the performance evaluation must be corrected before any base-case (with typical emissions) and future-year modeling is conducted. Corrections are usually made to model inputs such as emission-rate estimates or meteorology and/or to the air quality model itself, in modules that describe specific processes. Use of ground-level measurements that follow approved protocols is recommended for evaluating model performance. However, ground-level monitoring networks are spatially sparse, especially for particulate matter. Satellite retrievals of atmospheric chemical properties such as aerosol optical depth (AOD) provide spatial coverage that can compensate for the sparseness of ground-level measurements. Satellite retrievals can also help diagnose potential model or data problems in the upper troposphere. It is possible to achieve good model performance near the ground, but have, for example, erroneous sources or sinks in the upper troposphere that may result in misleading and unrealistic responses to emission reductions. Despite these advantages, satellite retrievals are rarely used in model performance evaluation, especially for regulatory modeling purposes, due to the high uncertainty in retrievals associated with various contaminations, for example by clouds. In this study, 2007 was selected as the base year for SIP modeling in the southeastern U.S. Performance of the Community Multiscale Air Quality (CMAQ) model, at a 12-km horizontal resolution, for this annual simulation is evaluated using both recommended ground-level measurements and non-traditional satellite

  10. Issues in performance assessments for disposal of US Department of Energy low-level waste

    International Nuclear Information System (INIS)

    Wood, D.E.; Wilhite, E.L.; Duggan, G.J.

    1994-12-01

    The US Department of Energy (DOE) and its contractors have long been pioneers in the field of radiological performance assessment (PA). Much effort has been expended in developing technology and acquiring data to facilitate the assessment process. This is reflected in DOE Order 5820.2A, Radioactive Waste Management Chapter III of the Order lists policy and requirements to manage the DOEs low-level waste; performance objectives for low-level waste management are stated to ensure the protection of public health and the environment. A radiological PA is also required to demonstrate compliance with the performance objectives. DOE Order 5820.2A further requires that an Oversight and Peer Review Panel be established to ensure consistency and technical quality around the DOE complex in the development and application of PA models that include site-specific geohydrology and waste composition. The DOE has also established a Performance Assessment Task Team (PATT) to integrate the activities of sites that are preparing PAs. The PATT's purpose is to recommend policy and guidance to DOE on issues that impact PAs so that the approaches taken are as consistent as possible across the DOE complex

  11. Transformational leadership climate : Performance linkages, mechanisms, and boundary conditions at the organizational level

    NARCIS (Netherlands)

    Menges, J.; Walter, F.; Vogel, B.; Bruch, H.

    2011-01-01

    Transformational leadership (TFL) climate describes the degree to which leaders throughout an organization engage in TFL behaviors. In this study, we investigate performance linkages, mechanisms, and boundary conditions of TFL climate at the organizational level of analysis. In a sample of 158

  12. A cross-level investigation of informal field-based learning and performance improvements.

    Science.gov (United States)

    Wolfson, Mikhail A; Tannenbaum, Scott I; Mathieu, John E; Maynard, M Travis

    2018-01-01

    Organizations often operate in complex and dynamic environments which place a premium on employees' ongoing learning and acquisition of new competencies. Additionally, the majority of learning in organizations does not take place in formal training settings, but we know relatively little about how informal field-based learning (IFBL) behaviors relate to changes in job performance. In this study, we first clarified the construct of IFBL as a subset of informal learning. Second, on the basis of this clarified construct definition, we developed a measure of IFBL behaviors and demonstrated its psychometric properties using (a) a sample of subject matter experts who made item content validity judgments and (b) both an Amazon Mechanical Turk sample (N = 400) and a sample of 1,707 healthcare employees. Third, we advanced a grounded theory of IFBL in healthcare, and related it to individuals' regulatory foci and contextual moderators of IFBL behaviors-job performance relationships using a cross-level design and lagged nonmethod bound measures. Specifically, using a sample of 407 healthcare workers from 49 hospital units, our results suggested that promotion-focused individuals, especially in well-staffed units, readily engage in IFBL behaviors. Additionally, we found that the IFBL-changes in job performance relationship was strengthened to the extent that individuals worked in units with relatively nonpunitive climates. Interestingly, staffing levels had a weakening moderating effect on the positive IFBL-performance improvements relationship. Detailed follow-up analyses revealed that the peculiar effect was attributable to differential relationships from IFBL subdimensions. Implications for future theory building, research, and practice are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  13. Use of PSA Level 2 analysis for improving containment performance. Report of a technical committee meeting

    International Nuclear Information System (INIS)

    1998-03-01

    In order to discuss and exchange experience on different aspects of methods associated with Level 2 PSA and its applications for improving containment performance, the IAEA held a Technical Committee meeting in Vienna in December 1996. The meeting, which was attended by 26 participants from 20 Member States, provided a broad forum for discussion. The meeting addressed the issues related to the actual performance of Level 2 PSA studies as well as the insights gained from applications to improve containment performance. Particular attention was given to studies and applications for WWER type reactors, for which Level 2 work is still in its early stages, and for channel type reactors where modelling of accident progression is complex and significantly different from vessel type light water reactors. This TECDOC contains the papers presented at the meeting and the results of extensive discussions which were held in specific working groups

  14. Current construction status of Korea Wolsong Nuclear Environment Management Center (low and intermediate level radioactive waste disposal facility)

    International Nuclear Information System (INIS)

    Suzuki, Yasuo

    2010-01-01

    Through the RANDEC delegation tour to Korea in Nov. 2009, we have earned new information on recent development of the radioactive waste management in Korea. In this report, we will introduce such development in Korea, focusing on the current construction status of Korean LILW (low and intermediate level radioactive waste) disposal site, now called, Wolsong Nuclear Environment Management Center. (author)

  15. Performance evaluation and operational experience with a semi-automatic monitor for the radiological characterization of low-level wastes

    International Nuclear Information System (INIS)

    Davey, E.C.; Csullog, G.W.

    1987-03-01

    Chalk River Nuclear Laboratories (CRNL) have undertaken a Waste Disposal Project to co-ordinate the transition from the current practice of interim storage to permanent disposal for low-level radioactive wastes (LLW). The strategy of the project is to classify and segregate waste segments according to their hazardous radioactive lifetimes and to emplace them in disposal facilities engineered to isolate and contain them. To support this strategy, a waste characterization program was set up to estimate the volume and radioisotope inventories of the wastes managed by CRNL. A key element of the program is the demonstration of a non-invasive measurement technique for the isotope-specific characterization of solid LLW. This paper describes the approach taken at CRNL for the non-invasive assay of LLW and the field performance and early operational experience with a waste characterization monitor to be used in a waste processing facility

  16. Performance evaluation and operational experience with a semi-automatic monitor for the radiological characterization of low-level wastes

    International Nuclear Information System (INIS)

    Davey, E.C.; Csullog, G.W.

    1987-01-01

    Chalk River Nuclear Laboratories (CRNL) have undertaken a Waste Disposal Project to co-ordinate the transition from the current practice of interim storage to permanent disposal for low-level radioactive wastes (LLW). The strategy of the project is to classify and segregate waste segments according to their hazardous radioactive lifetimes and to emplace them in disposal facilities engineered to isolate and contain them. To support this strategy, a waste characterization program was set up to estimate the volume and radioisotope inventories of the wastes managed by CRNL. A key element of the program is the demonstration of a non-invasive measurement technique for the isotope-specific characterization of solid LLW. This paper describes the approach taken at CRNL for the non-invasive assay of LLW and the field performance and early operational experience with a waste characterization monitor to be used in a waste processing facility

  17. Evaluation of different jumping tests in defining position-specific and performance-level differences in high level basketball players

    Directory of Open Access Journals (Sweden)

    Miran Pehar

    2017-04-01

    Full Text Available The importance of jumping ability in basketball is well known, but there is an evident lack of studies that have examined different jumping testing protocols in basketball players at advanced levels. The aim of this study was to assess the applicability of different tests of jumping capacity in identifying differences between (i playing position and (ii competitive levels of professional players. Participants were 110 male professional basketball players (height: 194.92±8.09 cm; body mass: 89.33±10.91 kg; 21.58±3.92 years of age; Guards, 49; Forwards, 22; Centres, 39 who competed in the first (n = 58 and second division (n = 52. The variables included anthropometrics and jumping test performance. Jumping performances were evaluated by the standing broad jump (SBJ, countermovement jump (CMJ, reactive strength index (RSI, repeated reactive strength ability (RRSA and four running vertical jumps: maximal jump with (i take-off from the dominant leg and (ii non-dominant leg, lay-up shot jump with take-off from the (iii dominant leg and (iv non-dominant leg. First-division players were taller (ES: 0.76, 95%CI: 0.35-1.16, moderate differences, heavier (0.69, 0.29-1.10, had higher maximal reach height (0.67, 0.26-1.07, moderate differences, and had lower body fat % (-0.87, -1.27-0.45, moderate differences than second-division players. The playing positions differed significantly in three of four running jump achievements, RSI and RRSA, with Centres being least successful. The first-division players were superior to second-division players in SBJ (0.63, 0.23-1.03; 0.87, 0.26-1.43; 0.76, 0.11-1.63, all moderate differences, for total sample, Guards, and Forwards, respectively. Running vertical jumps and repeated jumping capacity can be used as valid measures of position-specific jumping ability in basketball. The differences between playing levels in vertical jumping achievement can be observed by assessing vertical jump scores together with differences

  18. Evaluation of different jumping tests in defining position-specific and performance-level differences in high level basketball players.

    Science.gov (United States)

    Pehar, Miran; Sekulic, Damir; Sisic, Nedim; Spasic, Miodrag; Uljevic, Ognjen; Krolo, Ante; Milanovic, Zoran; Sattler, Tine

    2017-09-01

    The importance of jumping ability in basketball is well known, but there is an evident lack of studies that have examined different jumping testing protocols in basketball players at advanced levels. The aim of this study was to assess the applicability of different tests of jumping capacity in identifying differences between (i) playing position and (ii) competitive levels of professional players. Participants were 110 male professional basketball players (height: 194.92±8.09 cm; body mass: 89.33±10.91 kg; 21.58±3.92 years of age; Guards, 49; Forwards, 22; Centres, 39) who competed in the first (n = 58) and second division (n = 52). The variables included anthropometrics and jumping test performance. Jumping performances were evaluated by the standing broad jump (SBJ), countermovement jump (CMJ), reactive strength index (RSI), repeated reactive strength ability (RRSA) and four running vertical jumps: maximal jump with (i) take-off from the dominant leg and (ii) non-dominant leg, lay-up shot jump with take-off from the (iii) dominant leg and (iv) non-dominant leg. First-division players were taller (ES: 0.76, 95%CI: 0.35-1.16, moderate differences), heavier (0.69, 0.29-1.10), had higher maximal reach height (0.67, 0.26-1.07, moderate differences), and had lower body fat % (-0.87, -1.27-0.45, moderate differences) than second-division players. The playing positions differed significantly in three of four running jump achievements, RSI and RRSA, with Centres being least successful. The first-division players were superior to second-division players in SBJ (0.63, 0.23-1.03; 0.87, 0.26-1.43; 0.76, 0.11-1.63, all moderate differences, for total sample, Guards, and Forwards, respectively). Running vertical jumps and repeated jumping capacity can be used as valid measures of position-specific jumping ability in basketball. The differences between playing levels in vertical jumping achievement can be observed by assessing vertical jump scores together with differences

  19. Transcranial direct current stimulation (tDCS) to the supplementary motor area (SMA) influences performance on motor tasks.

    Science.gov (United States)

    Hupfeld, K E; Ketcham, C J; Schneider, H D

    2017-03-01

    The supplementary motor area (SMA) is believed to be highly involved in the planning and execution of both simple and complex motor tasks. This study aimed to examine the role of the SMA in planning the movements required to complete reaction time, balance, and pegboard tasks using anodal transcranial direct current stimulation (tDCS), which passes a weak electrical current between two electrodes, in order to modulate neuronal activity. Twenty healthy adults were counterbalanced to receive either tDCS (experimental condition) or no tDCS (control condition) for 3 days. During administration of tDCS, participants performed a balance task significantly faster than controls. After tDCS, subjects significantly improved their simple and choice reaction time. These results demonstrate that the SMA is highly involved in planning and executing fine and gross motor skill tasks and that tDCS is an effective modality for increasing SMA-related performance on these tasks. The findings may be generalizable and therefore indicate implications for future interventions using tDCS as a therapeutic tool.

  20. Scheduler-dependent inter-cell interference and its impact on LTE uplink performance at flow level

    NARCIS (Netherlands)

    Dimitrova, D.C.; Heijenk, Geert; van den Berg, Hans Leo; Yankov, S.; Masip Bruin, Xavier; Verchere, Dominique; Tsaoussidis, Vassilis; Yannuzzi, Marcelo

    The Long Term Evolution (LTE) cellular technology is ex- pected to extend the capacity and improve the performance of current 3G cellular networks. Among the key mechanisms in LTE responsible for traffic management is the packet scheduler, which handles the al- location of resources to active flows