Sample records for active power quality

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

    NASA Astrophysics Data System (ADS)

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

    2018-06-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2018-03-01

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

  3. Power Quality Improvement by Unified Power Quality Conditioner Based on CSC Topology Using Synchronous Reference Frame Theory

    PubMed Central

    Dharmalingam, Rajasekaran; Dash, Subhransu Sekhar; Senthilnathan, Karthikrajan; Mayilvaganan, Arun Bhaskar; Chinnamuthu, Subramani

    2014-01-01

    This paper deals with the performance of unified power quality conditioner (UPQC) based on current source converter (CSC) topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems. PMID:25013854

  4. Power quality improvement by unified power quality conditioner based on CSC topology using synchronous reference frame theory.

    PubMed

    Dharmalingam, Rajasekaran; Dash, Subhransu Sekhar; Senthilnathan, Karthikrajan; Mayilvaganan, Arun Bhaskar; Chinnamuthu, Subramani

    2014-01-01

    This paper deals with the performance of unified power quality conditioner (UPQC) based on current source converter (CSC) topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems.

  5. MATLAB Simulation of UPQC for Power Quality Mitigation Using an Ant Colony Based Fuzzy Control Technique

    PubMed Central

    Kumarasabapathy, N.; Manoharan, P. S.

    2015-01-01

    This paper proposes a fuzzy logic based new control scheme for the Unified Power Quality Conditioner (UPQC) for minimizing the voltage sag and total harmonic distortion in the distribution system consequently to improve the power quality. UPQC is a recent power electronic module which guarantees better power quality mitigation as it has both series-active and shunt-active power filters (APFs). The fuzzy logic controller has recently attracted a great deal of attention and possesses conceptually the quality of the simplicity by tackling complex systems with vagueness and ambiguity. In this research, the fuzzy logic controller is utilized for the generation of reference signal controlling the UPQC. To enable this, a systematic approach for creating the fuzzy membership functions is carried out by using an ant colony optimization technique for optimal fuzzy logic control. An exhaustive simulation study using the MATLAB/Simulink is carried out to investigate and demonstrate the performance of the proposed fuzzy logic controller and the simulation results are compared with the PI controller in terms of its performance in improving the power quality by minimizing the voltage sag and total harmonic distortion. PMID:26504895

  6. Development of Real Time Implementation of 5/5 Rule based Fuzzy Logic Controller Shunt Active Power Filter for Power Quality Improvement

    NASA Astrophysics Data System (ADS)

    Puhan, Pratap Sekhar; Ray, Pravat Kumar; Panda, Gayadhar

    2016-12-01

    This paper presents the effectiveness of 5/5 Fuzzy rule implementation in Fuzzy Logic Controller conjunction with indirect control technique to enhance the power quality in single phase system, An indirect current controller in conjunction with Fuzzy Logic Controller is applied to the proposed shunt active power filter to estimate the peak reference current and capacitor voltage. Current Controller based pulse width modulation (CCPWM) is used to generate the switching signals of voltage source inverter. Various simulation results are presented to verify the good behaviour of the Shunt active Power Filter (SAPF) with proposed two levels Hysteresis Current Controller (HCC). For verification of Shunt Active Power Filter in real time, the proposed control algorithm has been implemented in laboratory developed setup in dSPACE platform.

  7. Sex-specific relationships of physical activity, body composition, and muscle quality with lower-extremity physical function in older men and women.

    PubMed

    Straight, Chad R; Brady, Anne O; Evans, Ellen

    2015-03-01

    This study aims to determine the sex-specific relationships of physical activity, body composition, and muscle quality with lower-extremity physical function in older men and women. Seventy-nine community-dwelling men (n = 39; mean [SD] age, 76.1 [6.2] y; mean [SD] body mass index, 27.3 [3.8] kg/m(2)) and women (n = 40; mean [SD] age, 75.8 [5.5] y; mean [SD] body mass index, 27.0 [3.8] kg/m(2)) were assessed for physical activity via questionnaire, body composition via dual-energy x-ray absorptiometry scanning, leg extension power using the Nottingham power rig, and muscle quality (W/kg; the ratio of leg extension power [W] to lower-body mineral-free lean mass [kg]). A composite measure of physical function was obtained by summing Z scores from the 6-minute walk, 8-ft up-and-go test, and 30-second chair-stand test. As expected, men had significantly greater levels of physical activity, lower adiposity, greater lean mass, higher leg extension power, and greater muscle quality compared with women (all P < 0.05). In linear regression analyses, muscle quality and physical activity were the strongest predictors of lower-extremity physical function in men and independently explained 42% and 29% of the variance, respectively. In women, muscle quality (16%) and percent body fat (12%) were independent predictors after adjustment for covariates. Muscle quality is the strongest predictor of lower-extremity physical function in men and women, but sex impacts the importance of physical activity and adiposity. These findings suggest that older men and women may benefit from different intervention strategies for preventing physical disability and also highlight the importance of weight management for older women to preserve physical function.

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

    PubMed

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

    2017-10-12

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

  9. Quality assurance program for isotopic power systems

    NASA Astrophysics Data System (ADS)

    Hannigan, R. L.; Harnar, R. R.

    1982-12-01

    The Sandia National Laboratories Quality Assurance Program that applies to non-weapon (reimbursable) Radioisotopic Thermoelectric Generators is summarized. The program was implemented over the past 16 years on power supplies used in various space and terrestrial systems. The quality assurance (QA) activity of the program is in support of the Department of Energy, Office of Space Nuclear Projects. Basic elements of the program are described and examples of program documentation are presented.

  10. A Review of Distributed Control Techniques for Power Quality Improvement in Micro-grids

    NASA Astrophysics Data System (ADS)

    Zeeshan, Hafiz Muhammad Ali; Nisar, Fatima; Hassan, Ahmad

    2017-05-01

    Micro-grid is typically visualized as a small scale local power supply network dependent on distributed energy resources (DERs) that can operate simultaneously with grid as well as in standalone manner. The distributed generator of a micro-grid system is usually a converter-inverter type topology acting as a non-linear load, and injecting harmonics into the distribution feeder. Hence, the negative effects on power quality by the usage of distributed generation sources and components are clearly witnessed. In this paper, a review of distributed control approaches for power quality improvement is presented which encompasses harmonic compensation, loss mitigation and optimum power sharing in multi-source-load distributed power network. The decentralized subsystems for harmonic compensation and active-reactive power sharing accuracy have been analysed in detail. Results have been validated to be consistent with IEEE standards.

  11. Why do electricity policy and competitive markets fail to use advanced PV systems to improve distribution power quality?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McHenry, Mark P.; Johnson, Jay; Hightower, Mike

    The increasing pressure for network operators to meet distribution network power quality standards with increasing peak loads, renewable energy targets, and advances in automated distributed power electronics and communications is forcing policy-makers to understand new means to distribute costs and benefits within electricity markets. Discussions surrounding how distributed generation (DG) exhibits active voltage regulation and power factor/reactive power control and other power quality capabilities are complicated by uncertainties of baseline local distribution network power quality and to whom and how costs and benefits of improved electricity infrastructure will be allocated. DG providing ancillary services that dynamically respond to the networkmore » characteristics could lead to major network improvements. With proper market structures renewable energy systems could greatly improve power quality on distribution systems with nearly no additional cost to the grid operators. Renewable DG does have variability challenges, though this issue can be overcome with energy storage, forecasting, and advanced inverter functionality. This paper presents real data from a large-scale grid-connected PV array with large-scale storage and explores effective mitigation measures for PV system variability. As a result, we discuss useful inverter technical knowledge for policy-makers to mitigate ongoing inflation of electricity network tariff components by new DG interconnection requirements or electricity markets which value power quality and control.« less

  12. Why do electricity policy and competitive markets fail to use advanced PV systems to improve distribution power quality?

    DOE PAGES

    McHenry, Mark P.; Johnson, Jay; Hightower, Mike

    2016-01-01

    The increasing pressure for network operators to meet distribution network power quality standards with increasing peak loads, renewable energy targets, and advances in automated distributed power electronics and communications is forcing policy-makers to understand new means to distribute costs and benefits within electricity markets. Discussions surrounding how distributed generation (DG) exhibits active voltage regulation and power factor/reactive power control and other power quality capabilities are complicated by uncertainties of baseline local distribution network power quality and to whom and how costs and benefits of improved electricity infrastructure will be allocated. DG providing ancillary services that dynamically respond to the networkmore » characteristics could lead to major network improvements. With proper market structures renewable energy systems could greatly improve power quality on distribution systems with nearly no additional cost to the grid operators. Renewable DG does have variability challenges, though this issue can be overcome with energy storage, forecasting, and advanced inverter functionality. This paper presents real data from a large-scale grid-connected PV array with large-scale storage and explores effective mitigation measures for PV system variability. As a result, we discuss useful inverter technical knowledge for policy-makers to mitigate ongoing inflation of electricity network tariff components by new DG interconnection requirements or electricity markets which value power quality and control.« less

  13. Training Quality: Before and after Winning the Deming Prize.

    ERIC Educational Resources Information Center

    Magennis, Jo P.

    1995-01-01

    Describes the Quality Improvement Program developed by Florida Power and Light's Nuclear Training organization that was awarded the Deming Application Prize for quality control. Training quality, team activities, training's role in business planning, customer involvement and evaluation, and continuous improvement of training are discussed. (LRW)

  14. Performance Evaluation of UPQC under Nonlinear Unbalanced Load Conditions Using Synchronous Reference Frame Based Control

    NASA Astrophysics Data System (ADS)

    Kota, Venkata Reddy; Vinnakoti, Sudheer

    2017-12-01

    Today, maintaining Power Quality (PQ) is very important in the growing competent world. With new equipments and devices, new challenges are also being put before power system operators. Unified Power Quality Conditioner (UPQC) is proposed to mitigate many power quality problems and to improve the performance of the power system. In this paper, an UPQC with Fuzzy Logic controller for capacitor voltage balancing is proposed in Synchronous Reference Frame (SRF) based control with Modified Phased Locked Loop (MPLL). The proposed controller with SRF-MPLL based control is tested under non-linear and unbalanced load conditions. The system is developed in Matlab/Simulink and its performance is analyzed under various conditions like non-linear, unbalanced load and polluted supply voltage including voltage sag/swells. Active and reactive power flow in the system, power factor and %THD of voltages and currents before and after compensation are also analyzed in this work. Results prove the applicability of the proposed scheme for power quality improvement. It is observed that the fuzzy controller gives better performance than PI controller with faster capacitor voltage balancing and also improves the dynamic performance of the system.

  15. Performance of unified power quality conditioner (UPQC) based on fuzzy controller for attenuating of voltage and current harmonics

    NASA Astrophysics Data System (ADS)

    Milood Almelian, Mohamad; Mohd, Izzeldin I.; Asghaiyer Omran, Mohamed; Ullah Sheikh, Usman

    2018-04-01

    Power quality-related issues such as current and voltage distortions can adversely affect home and industrial appliances. Although several conventional techniques such as the use of passive and active filters have been developed to increase power quality standards, these methods have challenges and are inadequate due to the increasing number of applications. The Unified Power Quality Conditioner (UPQC) is a modern strategy towards correcting the imperfections of voltage and load current supply. A UPQC is a combination of both series and shunt active power filters in a back-to-back manner with a common DC link capacitor. The control of the voltage of the DC link capacitor is important in achieving a desired UPQC performance. In this paper, the UPQC with a Fuzzy logic controller (FLC) was used to precisely eliminate the imperfections of voltage and current harmonics. The results of the simulation studies using MATLAB/Simulink and Simpower system programming for R-L load associated through an uncontrolled bridge rectifier was used to assess the execution process. The UPQC with FLC was simulated for a system with distorted load current and a system with distorted source voltage and load current. The outcome of the comparison of %THD in the load current and source voltage before and after using UPQC for the two cases was presented.

  16. Control Strategy of Active Power Filter Based on Modular Multilevel Converter

    NASA Astrophysics Data System (ADS)

    Xie, Xifeng

    2018-03-01

    To improve the capacity, pressure resistance and the equivalent switching frequency of active power filter (APF), a control strategy of APF based on Modular Multilevel Converter (MMC) is presented. In this Control Strategy, the indirect current control method is used to achieve active current and reactive current decoupling control; Voltage Balance Control Strategy is to stabilize sub-module capacitor voltage, the predictive current control method is used to Track and control of harmonic currents. As a result, the harmonic current is restrained, and power quality is improved. Finally, the simulation model of active power filter controller based on MMC is established in Matlab/Simulink, the simulation proves that the proposed strategy is feasible and correct.

  17. Enhanced power quality based single phase photovoltaic distributed generation system

    NASA Astrophysics Data System (ADS)

    Panda, Aurobinda; Pathak, M. K.; Srivastava, S. P.

    2016-08-01

    This article presents a novel control strategy for a 1-ϕ 2-level grid-tie photovoltaic (PV) inverter to enhance the power quality (PQ) of a PV distributed generation (PVDG) system. The objective is to obtain the maximum benefits from the grid-tie PV inverter by introducing current harmonics as well as reactive power compensation schemes in its control strategy, thereby controlling the PV inverter to achieve multiple functions in the PVDG system such as: (1) active power flow control between the PV inverter and the grid, (2) reactive power compensation, and (3) grid current harmonics compensation. A PQ enhancement controller (PQEC) has been designed to achieve the aforementioned objectives. The issue of underutilisation of the PV inverter in nighttime has also been addressed in this article and for the optimal use of the system; the PV inverter is used as a shunt active power filter in nighttime. A prototype model of the proposed system is developed in the laboratory, to validate the effectiveness of the control scheme, and is tested with the help of the dSPACE DS1104 platform.

  18. Phenotypic Variation for Diastatic power, ß-Amylase Activity, and ß-Amylase Thermostability vs. Allelic Variation at the Bmy1 Locus in a Sample of North American Barley Germplasm

    USDA-ARS?s Scientific Manuscript database

    Malting quality data including diastatic power, ß-amylase activity, and ß-amylase thermostability, were collected on malts from three barley (Hordeum vulgare L.) breeding program trials containing two growth habits and 165 lines grown in multiple environments. We attempted to identify causal polymor...

  19. Gibberellic acid (GA3) induced changes in proanthocyanidins and malt quality of two- and six-row husked barleys.

    PubMed

    Yadav, S K; Luthra, Y P; Sood, D R; Aggarwal, N K

    2000-01-01

    Analysis of husked barleys for proanthocyanidins and malt quality attributes has shown that not a single variety is free of proanthocyanidins. The proanthocyanidins in barley grains varied from 3.85 to 4.94 mg/g as catechin equivalent. The concentration of proanthocyanidins decreased, while total soluble sugars, reducing sugars, diastatic power and beta-amylase activity increased during maltings as well as with exogenous gibberellic acid (GA3) application. Alfa 93 (two-row) and RD2560 (six-row) varieties appeared to be superior for malting and brewing purposes on the basis of proanthocyanidins, total phenols, diastatic power and beta-amylase activity. It is suggested that exogenous application of GA3 at 15 ppm may be useful for producing good quality malt from barley grains.

  20. Protective Controller against Cascade Outages with Selective Harmonic Compensation Function

    NASA Astrophysics Data System (ADS)

    Abramovich, B. N.; Kuznetsov, P. A.; Sychev, Yu A.

    2018-05-01

    The paper presents data on the power quality and development of protective devices for the power networks with distributed generation (DG).The research has shown that power quality requirements for DG networks differ from conventional ones. That is why main tendencies, protective equipment and filters should be modified. There isa developed algorithm for detection and prevention of cascade outages that can lead to the blackoutin DG networks and there was a proposed structural scheme for a new active power filter for selective harmonics compensation. Analysis of these theories and equipment led to the development of protective device that could monitor power balance and cut off non-important consumers. The last part of the article describes a microcontroller prototype developed for connection to the existing power station control center.

  1. Continuous microwave pasteurization of a vegetable smoothie improves its physical quality and hinders detrimental enzyme activity.

    PubMed

    Arjmandi, Mitra; Otón, Mariano; Artés, Francisco; Artés-Hernández, Francisco; Gómez, Perla A; Aguayo, Encarna

    2017-01-01

    The effect of a pasteurization treatment at 90 ± 2 ℃ for 35 s provided by continuous microwave under different doses (low power/long time and high power/short time) or conventional pasteurization on the quality of orange-colored smoothies and their changes throughout 45 days of storage at 5 ℃ was investigated. A better color retention of the microwave pasteurization- treated smoothie using high power/short time than in conventionally processed sample was evidenced by the stability of the hue angle. The continuous microwave heating increased the viscosity of the smoothie more than the conventional pasteurization in comparison with non-treated samples. Lower residual enzyme activities from peroxidase, pectin methylesterase and polygalacturonase were obtained under microwave heating, specifically due to the use of higher power/shorter time. For this kind of smoothie, polygalacturonase was the more thermo-resistant enzyme and could be used as an indicator of pasteurization efficiency. The use of a continuous semi-industrial microwave using higher power and shorter time, such as 1600 W/206 s and 3600 W/93 s, resulted in better quality smoothies and greater enzyme reduction than conventional thermal treatment. © The Author(s) 2016.

  2. Visual sensitivity of river recreation to power plants

    Treesearch

    David H. Blau; Michael C. Bowie

    1979-01-01

    The consultants were asked by the Power Plant Siting Staff of the Minnesota Environmental Quality Council to develop a methodology for evaluating the sensitivity of river-related recreational activities to visual intrusion by large coal-fired power plants. The methodology, which is applicable to any major stream in the state, was developed and tested on a case study...

  3. Modelling and Simulation of Single-Phase Series Active Compensator for Power Quality Improvement

    NASA Astrophysics Data System (ADS)

    Verma, Arun Kumar; Mathuria, Kirti; Singh, Bhim; Bhuvaneshwari, G.

    2017-10-01

    A single-phase active series compensator is proposed in this work to reduce harmonic currents at the ac mains and to regulate the dc link voltage of a diode bridge rectifier (DBR) that acts as the front end converter for a voltage source inverter feeding an ac motor. This ac motor drive is used in any of the domestic, commercial or industrial appliances. Under fluctuating ac mains voltages, the dc link voltage of the DBR depicts wide variations and hence the ac motor is used at reduced rating as compared to its name-plate rating. The active series compensator proposed here provides dual functions of improving the power quality at the ac mains and regulating the dc link voltage thus averting the need for derating of the ac motor.

  4. Preface to volume 1: status and trends of water quality worldwide

    USGS Publications Warehouse

    Larsen, Matthew C.; Ahuja, Satinder; Eimers, Jo Leslie; Edited by Ahuja, Satinder

    2013-01-01

    Water quality and water quantity are closely linked. In all regions of the world, the quality and quantity of water must be considered together in order to sustain abundant water of the quality needed for drinking, irrigation, environmental health, industry, power generation, and recreation. Protecting and managing water to meet water needs requires comprehensive information and understanding of the impacts of natural settings and anthropogenic activities on water quality.

  5. An analytical design approach for self-powered active lateral secondary suspensions for railway vehicles

    NASA Astrophysics Data System (ADS)

    Wang, Peng; Li, Hong; Zhang, Jiye; Mei, TX

    2015-10-01

    In this paper, an analytical design approach for the development of self-powered active suspensions is investigated and is applied to optimise the control system design for an active lateral secondary suspension for railway vehicles. The conditions for energy balance are analysed and the relationship between the ride quality improvement and energy consumption is discussed in detail. The modal skyhook control is applied to analyse the energy consumption of this suspension by separating its dynamics into the lateral and yaw modes, and based on a simplified model, the average power consumption of actuators is computed in frequency domain by using the power spectral density of lateral alignment of track irregularities. Then the impact of control gains and actuators' key parameters on the performance for both vibration suppressing and energy recovery/storage is analysed. Computer simulation is used to verify the obtained energy balance condition and to demonstrate that the improved ride comfort is achieved by this self-powered active suspension without any external power supply.

  6. Improved power control using optimal adjustable coefficients for three-phase photovoltaic inverter under unbalanced grid voltage.

    PubMed

    Wang, Qianggang; Zhou, Niancheng; Lou, Xiaoxuan; Chen, Xu

    2014-01-01

    Unbalanced grid faults will lead to several drawbacks in the output power quality of photovoltaic generation (PV) converters, such as power fluctuation, current amplitude swell, and a large quantity of harmonics. The aim of this paper is to propose a flexible AC current generation method by selecting coefficients to overcome these problems in an optimal way. Three coefficients are brought in to tune the output current reference within the required limits of the power quality (the current harmonic distortion, the AC current peak, the power fluctuation, and the DC voltage fluctuation). Through the optimization algorithm, the coefficients can be determined aiming to generate the minimum integrated amplitudes of the active and reactive power references with the constraints of the inverter current and DC voltage fluctuation. Dead-beat controller is utilized to track the optimal current reference in a short period. The method has been verified in PSCAD/EMTDC software.

  7. Improved Power Control Using Optimal Adjustable Coefficients for Three-Phase Photovoltaic Inverter under Unbalanced Grid Voltage

    PubMed Central

    Wang, Qianggang; Zhou, Niancheng; Lou, Xiaoxuan; Chen, Xu

    2014-01-01

    Unbalanced grid faults will lead to several drawbacks in the output power quality of photovoltaic generation (PV) converters, such as power fluctuation, current amplitude swell, and a large quantity of harmonics. The aim of this paper is to propose a flexible AC current generation method by selecting coefficients to overcome these problems in an optimal way. Three coefficients are brought in to tune the output current reference within the required limits of the power quality (the current harmonic distortion, the AC current peak, the power fluctuation, and the DC voltage fluctuation). Through the optimization algorithm, the coefficients can be determined aiming to generate the minimum integrated amplitudes of the active and reactive power references with the constraints of the inverter current and DC voltage fluctuation. Dead-beat controller is utilized to track the optimal current reference in a short period. The method has been verified in PSCAD/EMTDC software. PMID:25243215

  8. High power single-frequency and frequency-doubled laser with active compensation for the thermal lens effect of terbium gallium garnet crystal.

    PubMed

    Yin, Qiwei; Lu, Huadong; Su, Jing; Peng, Kunchi

    2016-05-01

    The thermal lens effect of terbium gallium garnet (TGG) crystal in a high power single-frequency laser severely limits the output power and the beam quality of the laser. By inserting a potassium dideuterium phosphate (DKDP) slice with negative thermo-optical coefficient into the laser resonator, the harmful influence of the thermal lens effect of the TGG crystal can be effectively mitigated. Using this method, the stable range of the laser is broadened, the bistability phenomenon of the laser during the process of changing the pump power is completely eliminated, the highest output power of an all-solid-state continuous-wave intracavity-frequency-doubling single-frequency laser at 532 nm is enhanced to 30.2 W, and the beam quality of the laser is significantly improved.

  9. Microwave flow and conventional heating effects on the physicochemical properties, bioactive compounds and enzymatic activity of tomato puree.

    PubMed

    Arjmandi, Mitra; Otón, Mariano; Artés, Francisco; Artés-Hernández, Francisco; Gómez, Perla A; Aguayo, Encarna

    2017-02-01

    Thermal processing causes a number of undesirable changes in physicochemical and bioactive properties of tomato products. Microwave (MW) technology is an emergent thermal industrial process that offers a rapid and uniform heating, high energy efficiency and high overall quality of the final product. The main quality changes of tomato puree after pasteurization at 96 ± 2 °C for 35 s, provided by a semi-industrial continuous microwave oven (MWP) under different doses (low power/long time to high power/short time) or by conventional method (CP) were studied. All heat treatments reduced colour quality, total antioxidant capacity and vitamin C, with a greater reduction in CP than in MWP. On the other hand, use of an MWP, in particular high power/short time (1900 W/180 s, 2700 W/160 s and 3150 W/150 s) enhanced the viscosity and lycopene extraction and decreased the enzyme residual activity better than with CP samples. For tomato puree, polygalacturonase was the more thermo-resistant enzyme, and could be used as an indicator of pasteurization efficiency. MWP was an excellent pasteurization technique that provided tomato puree with improved nutritional quality, reducing process times compared to the standard pasteurization process. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Amelioration de la qualite d'energie d'un systeme de conversion d'energie eolienne a base de machine asynchrone a double alimentation et connecte au reseau electrique =

    NASA Astrophysics Data System (ADS)

    Abderrahim, Iheb

    Wind power generation has grown strongly in the last decade. This results in the development of Wind Energy Conversion System WECS at the levels of modeling and electrical control. Modern WECS operate at varying wind speeds and are equipped with synchronous and asynchronous generators. Among these generators, the Doubly-Fed Induction Generator (DFIG) offers several advantages and capabilities of active and reactive power in four quadrants. WECS based DFIG also causes less conversion costs and minimum energy losses compared with a WECS based on a synchronous generator powered entirely by full scale of power converters. The connection of such a system to the electrical distribution network involves bidirectional operation of networks. This is clearly established in sub and super synchronous operating modes of DFIG. The grid provides the active power to the rotor of DFIG in sub synchronous operating mode and receives the active power of the rotor in super synchronous operating mode of DFIG. Energy quality is thus of major importance during the integration of wind power to the grid. Poor wave quality can affect network stability and could even cause major problems and consequences. This is even more critical where non-linear loads such as the switching power supplies and variable speed drives, are connected to the grid. The idea of this research work is how to mitigate the problems associated with the wave quality while ensuring better implementation of DFIG so that the whole of WECS remains insensitive to external disturbances and parametric variations. The Grid Side Converter (GSC) must be able to compensate harmonics, current unbalance and reactive power injected by a nonlinear three-phase unbalanced load connected to the grid. In addition to these innovative features to improve the conditions of operation of the grid, it provides also the power flow during different modes of operation of the DFIG. It is considered a simple, efficient and cost competitive solution by saving the use of other power equipment. At the same time, the energy efficiency of wind power conversion chain should be improved by extracting the MPPT. Searching allows us to select vector control and control in synchronous reference to achieve these objectives. WECS based DFIG is simulated in MATLAB SIMULINK in the presence of a non-linear balanced and unbalanced three-phase load.

  11. Energy, Transportation, Air Quality, Climate Change, Health Nexus: Sustainable Energy is Good for Our Health.

    PubMed

    Erickson, Larry E; Jennings, Merrisa

    2017-01-01

    The Paris Agreement on Climate Change has the potential to improve air quality and human health by encouraging the electrification of transportation and a transition from coal to sustainable energy. There will be human health benefits from reducing combustion emissions in all parts of the world. Solar powered charging infrastructure for electric vehicles adds renewable energy to generate electricity, shaded parking, and a needed charging infrastructure for electric vehicles that will reduce range anxiety. The costs of wind power, solar panels, and batteries are falling because of technological progress, magnitude of commercial activity, production experience, and competition associated with new trillion dollar markets. These energy and transportation transitions can have a very positive impact on health. The energy, transportation, air quality, climate change, health nexus may benefit from additional progress in developing solar powered charging infrastructure.

  12. The influence of sand mining towards the sustainability of power support and capacity of Lambidaro River

    NASA Astrophysics Data System (ADS)

    Juniah, Restu; Rahmi, Hisni

    2017-11-01

    Activities of sand mining on the surface stream (river) conducted by Panji Mahakarya company potentially cause various environmental issues. These problems include the destruction of the river ecosystem, decreased the quality of river water quality, increased water pollution load, and another effect on capacity and power support river. The Lambidaro River is one of the rivers found in Palembang, where the inhabitants who live around it take advantage of the existence of this river to meet their daily needs such as bathing, washing, and latrines. The purpose of this research is to know the influence of mining activities towards sustainability of the power support and capacity of the river. The method used in this research is to compare the availability of water and water needs of the population in determining the status of environmental power support based on regulation of the state minister of the environment number 17 in 2009 about the determination of the power guidance support environment in spatial regions, as well as using the index method of pollution based on the decision of the State Minister of the environment number 115 in 2003 about the determination of the status of water quality guidelines with parameters measured are TDS, TSS, pH, DO, COD, dan BOD5. The results of the calculation of the power support river are deficit where SA (34,200,655.64 m3/year) < DA (253,105,600 m3/year). The result of pollution index calculation at 5 water sampling locations shows that the condition of a river is in good condition (uncontaminated) and mild pollutant.

  13. Thin disk laser with unstable resonator and reduced output coupler

    NASA Astrophysics Data System (ADS)

    Gavili, Anwar; Shayganmanesh, Mahdi

    2018-05-01

    In this paper, feasibility of using unstable resonator with reduced output coupling in a thin disk laser is studied theoretically. Unstable resonator is modeled by wave-optics using Collins integral and iterative method. An Yb:YAG crystal with 250 micron thickness is considered as a quasi-three level active medium and modeled by solving rate equations of energy levels populations. The amplification of laser beam in the active medium is calculated based on the Beer-Lambert law and Rigrod method. Using generalized beam parameters method, laser beam parameters like, width, divergence, M2 factor, output power as well as near and far-field beam profiles are calculated for unstable resonator. It is demonstrated that for thin disk laser (with single disk) in spite of the low thickness of the disk which leads to low gain factor, it is possible to use unstable resonator (with reduced output coupling) and achieve good output power with appropriate beam quality. Also, the behavior of output power and beam quality versus equivalent Fresnel number is investigated and optimized value of output coupling for maximum output power is achieved.

  14. Energy, Transportation, Air Quality, Climate Change, Health Nexus: Sustainable Energy is Good for Our Health

    PubMed Central

    Erickson, Larry E.; Jennings, Merrisa

    2017-01-01

    The Paris Agreement on Climate Change has the potential to improve air quality and human health by encouraging the electrification of transportation and a transition from coal to sustainable energy. There will be human health benefits from reducing combustion emissions in all parts of the world. Solar powered charging infrastructure for electric vehicles adds renewable energy to generate electricity, shaded parking, and a needed charging infrastructure for electric vehicles that will reduce range anxiety. The costs of wind power, solar panels, and batteries are falling because of technological progress, magnitude of commercial activity, production experience, and competition associated with new trillion dollar markets. These energy and transportation transitions can have a very positive impact on health. The energy, transportation, air quality, climate change, health nexus may benefit from additional progress in developing solar powered charging infrastructure. PMID:29922702

  15. 10 CFR Appendix B to Part 50 - Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... related to the design, fabrication, construction, and testing of the structures, systems, and components... components. The pertinent requirements of this appendix apply to all activities affecting the safety-related..., which comprises those quality assurance actions related to the physical characteristics of a material...

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

    PubMed

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

    2017-09-01

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

  17. Power quality improvement by using STATCOM control scheme in wind energy generation interface to grid

    NASA Astrophysics Data System (ADS)

    Kirmani, Sheeraz; Kumar, Brijesh

    2018-01-01

    “Electric Power Quality (EPQ) is a term that refers to maintaining the near sinusoidal waveform of power distribution bus voltages and currents at rated magnitude and frequency”. Today customers are more aware of the seriousness that the power quality possesses, this prompt the utilities to assure good quality of power to their customer. The power quality is basically customer centric. Increased focus of utilities toward maintaining reliable power supply by employing power quality improvement tools has reduced the power outages and black out considerably. Good power quality is the characteristic of reliable power supply. Low power factor, harmonic pollution, load imbalance, fast voltage variations are some common parameters which are used to define the power quality. If the power quality issues are not checked i.e. the parameters that define power quality doesn't fall within the predefined standards than it will lead into high electricity bill, high running cost in industries, malfunctioning of equipments, challenges in connecting renewable. Capacitor banks, FACTS devices, harmonic filters, SVC’s (static voltage compensators), STATCOM (Static-Compensator) are the solutions to achieve the power quality. The performance of Wind turbine generators is affected by poor quality power, at the same time these wind power generating plant affects the power quality negatively. This paper presents the STATCOM-BESS (battery energy storage system) system and studies its impact on the power quality in a system which consists of wind turbine generator, non linear load, hysteresis controller for controlling the operation of STATCOM and grid. The model is simulated in the MATLAB/Simulink. This scheme mitigates the power quality issues, improves voltage profile and also reduces harmonic distortion of the waveforms. BESS level out the imbalances caused in real power due to intermittent nature of wind power available due to varying wind speeds.

  18. Power quality analysis based on spatial correlation

    NASA Astrophysics Data System (ADS)

    Li, Jiangtao; Zhao, Gang; Liu, Haibo; Li, Fenghou; Liu, Xiaoli

    2018-03-01

    With the industrialization and urbanization, the status of electricity in the production and life is getting higher and higher. So the prediction of power quality is the more potential significance. Traditional power quality analysis methods include: power quality data compression, disturbance event pattern classification, disturbance parameter calculation. Under certain conditions, these methods can predict power quality. This paper analyses the temporal variation of power quality of one provincial power grid in China from time angle. The distribution of power quality was analyzed based on spatial autocorrelation. This paper tries to prove that the research idea of geography is effective for mining the potential information of power quality.

  19. Substation Reactive Power Regulation Strategy

    NASA Astrophysics Data System (ADS)

    Zhang, Junfeng; Zhang, Chunwang; Ma, Daqing

    2018-01-01

    With the increasing requirements on the power supply quality and reliability of distribution network, voltage and reactive power regulation of substations has become one of the indispensable ways to ensure voltage quality and reactive power balance and to improve the economy and reliability of distribution network. Therefore, it is a general concern of the current power workers and operators that what kind of flexible and effective control method should be used to adjust the on-load tap-changer (OLTC) transformer and shunt compensation capacitor in a substation to achieve reactive power balance in situ, improve voltage pass rate, increase power factor and reduce active power loss. In this paper, based on the traditional nine-zone diagram and combining with the characteristics of substation, a fuzzy variable-center nine-zone diagram control method is proposed and used to make a comprehensive regulation of substation voltage and reactive power. Through the calculation and simulation of the example, this method is proved to have satisfactorily reconciled the contradiction between reactive power and voltage in real-time control and achieved the basic goal of real-time control of the substation, providing a reference value to the practical application of the substation real-time control method.

  20. Nuclear Technology. Course 30: Mechanical Inspection. Module 30-1, Pump Inspection.

    ERIC Educational Resources Information Center

    Wasil, Ed; Espy, John

    This first in a series of eight modules for a course titled Mechanical Inspection describes the type of pumps used in nuclear power plant systems, the basic operating principles of each type, and the inspection activities performed by the quality assurance/quality control technician. The module follows a typical format that includes the following…

  1. The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

    DTIC Science & Technology

    with greater range of motion and active power, will translate into improved functional performance, ambulatory safety (risk of falls) and quality of... life in trans-tibial amputees (TTA) who function as limited community ambulators. We will assess these outcomes in 54 veterans with TTA by randomizing

  2. An islanding detection methodology combining decision trees and Sandia frequency shift for inverter-based distributed generations

    DOE PAGES

    Azim, Riyasat; Li, Fangxing; Xue, Yaosuo; ...

    2017-07-14

    Distributed generations (DGs) for grid-connected applications require an accurate and reliable islanding detection methodology (IDM) for secure system operation. This paper presents an IDM for grid-connected inverter-based DGs. The proposed method is a combination of passive and active islanding detection techniques for aggregation of their advantages and elimination/minimisation of the drawbacks. In the proposed IDM, the passive method utilises critical system attributes extracted from local voltage measurements at target DG locations as well as employs decision tree-based classifiers for characterisation and detection of islanding events. The active method is based on Sandia frequency shift technique and is initiated only whenmore » the passive method is unable to differentiate islanding events from other system events. Thus, the power quality degradation introduced into the system by active islanding detection techniques can be minimised. Furthermore, a combination of active and passive techniques allows detection of islanding events under low power mismatch scenarios eliminating the disadvantage associated with the use of passive techniques alone. Finally, detailed case study results demonstrate the effectiveness of the proposed method in detection of islanding events under various power mismatch scenarios, load quality factors and in the presence of single or multiple grid-connected inverter-based DG units.« less

  3. An islanding detection methodology combining decision trees and Sandia frequency shift for inverter-based distributed generations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Azim, Riyasat; Li, Fangxing; Xue, Yaosuo

    Distributed generations (DGs) for grid-connected applications require an accurate and reliable islanding detection methodology (IDM) for secure system operation. This paper presents an IDM for grid-connected inverter-based DGs. The proposed method is a combination of passive and active islanding detection techniques for aggregation of their advantages and elimination/minimisation of the drawbacks. In the proposed IDM, the passive method utilises critical system attributes extracted from local voltage measurements at target DG locations as well as employs decision tree-based classifiers for characterisation and detection of islanding events. The active method is based on Sandia frequency shift technique and is initiated only whenmore » the passive method is unable to differentiate islanding events from other system events. Thus, the power quality degradation introduced into the system by active islanding detection techniques can be minimised. Furthermore, a combination of active and passive techniques allows detection of islanding events under low power mismatch scenarios eliminating the disadvantage associated with the use of passive techniques alone. Finally, detailed case study results demonstrate the effectiveness of the proposed method in detection of islanding events under various power mismatch scenarios, load quality factors and in the presence of single or multiple grid-connected inverter-based DG units.« less

  4. The association of quality of life with potentially remediable disruptions of circadian sleep/activity rhythms in patients with advanced lung cancer.

    PubMed

    Grutsch, James F; Ferrans, Carol; Wood, Patricia A; Du-Quiton, Jovelyn; Quiton, Dinah Faith T; Reynolds, Justin L; Ansell, Christine M; Oh, Eun Young; Daehler, Mary Ann; Levin, Robert D; Braun, Donald P; Gupta, Digant; Lis, Christopher G; Hrushesky, William J M

    2011-05-23

    Cancer patients routinely develop symptoms consistent with profound circadian disruption, which causes circadian disruption diminished quality of life. This study was initiated to determine the relationship between the severity of potentially remediable cancer-associated circadian disruption and quality of life among patients with advanced lung cancer. We concurrently investigated the relationship between the circadian rhythms of 84 advanced lung cancer patients and their quality of life outcomes as measured by the EORTC QLQ C30 and Ferrans and Powers QLI. The robustness and stability of activity/sleep circadian daily rhythms were measured by actigraphy. Fifty three of the patients in the study were starting their definitive therapy following diagnosis and thirty one patients were beginning second-line therapy. Among the patients who failed prior therapy, the median time between completing definitive therapy and baseline actigraphy was 4.3 months, (interquartile range 2.1 to 9.8 months). We found that circadian disruption is universal and severe among these patients compared to non-cancer-bearing individuals. We found that each of these patient's EORTC QLQ C30 domain scores revealed a compromised capacity to perform the routine activities of daily life. The severity of several, but not all, EORTC QLQ C30 symptom items correlate strongly with the degree of individual circadian disruption. In addition, the scores of all four Ferrans/Powers QLI domains correlate strongly with the degree of circadian disruption. Although Ferrans/Powers QLI domain scores show that cancer and its treatment spared these patients' emotional and psychological health, the QLI Health/Function domain score revealed high levels of patients' dissatisfaction with their health which is much worse when circadian disruption is severe. Circadian disruption selectively affects specific Quality of Life domains, such as the Ferrans/Powers Health/Function domain, and not others, such as EORTC QLQ C30 Physical Domain. These data suggest the testable possibility that behavioral, hormonal and/or light-based strategies to improve circadian organization may help patients suffering from advanced lung cancer to feel and function better.

  5. Assessment and mitigation of power quality problems for PUSPATI TRIGA Reactor (RTP)

    NASA Astrophysics Data System (ADS)

    Zakaria, Mohd Fazli; Ramachandaramurthy, Vigna K.

    2017-01-01

    An electrical power systems are exposed to different types of power quality disturbances. Investigation and monitoring of power quality are necessary to maintain accurate operation of sensitive equipment especially for nuclear installations. This paper will discuss the power quality problems observed at the electrical sources of PUSPATI TRIGA Reactor (RTP). Assessment of power quality requires the identification of any anomalous behavior on a power system, which adversely affects the normal operation of electrical or electronic equipment. A power quality assessment involves gathering data resources; analyzing the data (with reference to power quality standards) then, if problems exist, recommendation of mitigation techniques must be considered. Field power quality data is collected by power quality recorder and analyzed with reference to power quality standards. Normally the electrical power is supplied to the RTP via two sources in order to keep a good reliability where each of them is designed to carry the full load. The assessment of power quality during reactor operation was performed for both electrical sources. There were several disturbances such as voltage harmonics and flicker that exceeded the thresholds. To reduce these disturbances, mitigation techniques have been proposed, such as to install passive harmonic filters to reduce harmonic distortion, dynamic voltage restorer (DVR) to reduce voltage disturbances and isolate all sensitive and critical loads.

  6. FINDINGS OF A SYMPOSIUM ON COAL QUALITY.

    USGS Publications Warehouse

    Schweinfurth, Stanley P.; Garbini, Susan

    1985-01-01

    The U. S. Geological Survey (USGS) has been doing research on coal quality for almost a century. Most of the work of the USGS regarding coal went into efforts to assess the quantity of coal in the United States, not the quality. On April 9-11, 1985, the U. S. Geological Survey, along with cosponsors - the Association of American State Geologists, the U. S. Department of Energy, the Electric Power Research Institute, and the U. S. Environmental Protection Agency - convened a symposium on coal quality at the headquarters of the USGS in Reston, Virginia. The coal-quality symposium provided a forum for the discussion of a wide variety of topics with regard to coal-quality research and related activities. The coal community took advantage of that opportunity to recommend a large agenda of coal-research needs, not only for the USGS but for the entire spectrum of organizations that either actively pursue or fund research on coal quality.

  7. Response of Rocky Mountain elk (Cervus elaphus) to wind-power development

    USGS Publications Warehouse

    Walter, W. David; Leslie, David M.; Jenks, J.A.

    2006-01-01

    Wind-power development is occurring throughout North America, but its effects on mammals are largely unexplored. Our objective was to determine response (i.e., home-range, diet quality) of Rocky Mountain elk (Cervus elaphus) to wind-power development in southwestern Oklahoma. Ten elk were radiocollared in an area of wind-power development on 31 March 2003 and were relocated bi-weekly through March 2005. Wind-power construction was initiated on 1 June 2003 and was completed by December 2003 with 45 active turbines. The largest composite home range sizes (>80 km2) occurred April-June and September, regardless of the status of wind-power facility development. The smallest home range sizes (<50 km2) typically occurred in October-February when elk aggregated to forage on winter wheat. No elk left the study site during the study and elk freely crossed the gravel roads used to access the wind-power facility. Carbon and nitrogen isotopes and percent nitrogen in feces suggested that wind-power development did not affect nutrition of elk during construction. Although disturbance and loss of some grassland habitat was apparent, elk were not adversely affected by wind-power development as determined by home range and dietary quality.

  8. Active and Reactive Power Optimal Dispatch Associated with Load and DG Uncertainties in Active Distribution Network

    NASA Astrophysics Data System (ADS)

    Gao, F.; Song, X. H.; Zhang, Y.; Li, J. F.; Zhao, S. S.; Ma, W. Q.; Jia, Z. Y.

    2017-05-01

    In order to reduce the adverse effects of uncertainty on optimal dispatch in active distribution network, an optimal dispatch model based on chance-constrained programming is proposed in this paper. In this model, the active and reactive power of DG can be dispatched at the aim of reducing the operating cost. The effect of operation strategy on the cost can be reflected in the objective which contains the cost of network loss, DG curtailment, DG reactive power ancillary service, and power quality compensation. At the same time, the probabilistic constraints can reflect the operation risk degree. Then the optimal dispatch model is simplified as a series of single stage model which can avoid large variable dimension and improve the convergence speed. And the single stage model is solved using a combination of particle swarm optimization (PSO) and point estimate method (PEM). Finally, the proposed optimal dispatch model and method is verified by the IEEE33 test system.

  9. Human Connections.

    ERIC Educational Resources Information Center

    Sgroi, Angela; Saltiel, Iris M.

    1998-01-01

    The power of collaborative learning partnerships is the synergy created through productive, meaningful activity. Key elements include trust, respect, self-selection, mutual goals, a belief that the sum is greater than the parts, and complementary qualities. (SK)

  10. Capacity and reliability analyses with applications to power quality

    NASA Astrophysics Data System (ADS)

    Azam, Mohammad; Tu, Fang; Shlapak, Yuri; Kirubarajan, Thiagalingam; Pattipati, Krishna R.; Karanam, Rajaiah

    2001-07-01

    The deregulation of energy markets, the ongoing advances in communication networks, the proliferation of intelligent metering and protective power devices, and the standardization of software/hardware interfaces are creating a dramatic shift in the way facilities acquire and utilize information about their power usage. The currently available power management systems gather a vast amount of information in the form of power usage, voltages, currents, and their time-dependent waveforms from a variety of devices (for example, circuit breakers, transformers, energy and power quality meters, protective relays, programmable logic controllers, motor control centers). What is lacking is an information processing and decision support infrastructure to harness this voluminous information into usable operational and management knowledge to handle the health of their equipment and power quality, minimize downtime and outages, and to optimize operations to improve productivity. This paper considers the problem of evaluating the capacity and reliability analyses of power systems with very high availability requirements (e.g., systems providing energy to data centers and communication networks with desired availability of up to 0.9999999). The real-time capacity and margin analysis helps operators to plan for additional loads and to schedule repair/replacement activities. The reliability analysis, based on computationally efficient sum of disjoint products, enables analysts to decide the optimum levels of redundancy, aids operators in prioritizing the maintenance options for a given budget and monitoring the system for capacity margin. The resulting analytical and software tool is demonstrated on a sample data center.

  11. Development of optically pumped DBR-free semiconductor disk lasers (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Yang, Zhou; Albrecht, Alexander R.; Cederberg, Jeffrey G.; Sheik-Bahae, Mansoor

    2017-03-01

    Semiconductor disk lasers (SDLs) are attractive for applications requiring good beam quality, wavelength versatility, and high output powers. Typical SDLs utilize the active mirror geometry, where a semiconductor DBR is integrated with the active region by growth or post-growth bonding. This imposes restrictions for the SDL design, like material system choice, thermal management, and effective gain bandwidth. In DBR-free geometry, these restrictions can be alleviated. An integrated gain model predicts DBR-free geometry with twice the gain bandwidth of typical SDLs, which has been experimentally verified with active regions near 1 μm and 1.15 μm. The lift-off and bonding technique enables the integration of semiconductor active regions with arbitrary high quality substrates, allowing novel monolithic geometries. Bonding an active region onto a straight side of a commercial fused silica right angle prism, and attaching a high reflectivity mirror onto the hypotenuse side, with quasi CW pumping at 780 nm, lasing operation was achieved at 1037 nm with 0.2 mW average power at 1.6 mW average pump power. Laser dynamics show that thermal lens generation in the active region bottlenecks the laser efficiency. Investigations on total internal reflection based monolithic ring cavities are ongoing. These geometries would allow the intracavity integration of 2D materials or other passive absorbers, which could be relevant for stable mode locking. Unlike typical monolithic microchip SDLs, with the evanescent wave coupling technique, these monolithic geometries allow variable coupling efficiency.

  12. Modelling and Simulation of Grid Connected SPV System with Active Power Filtering Features

    NASA Astrophysics Data System (ADS)

    Saroha, Jaipal; Pandove, Gitanjali; Singh, Mukhtiar

    2017-09-01

    In this paper, the detailed simulation studies for a grid connected solar photovoltaic system (SPV) have been presented. The power electronics devices like DC-DC boost converter and grid interfacing inverter are most important components of proposed system. Here, the DC-DC boost converter is controlled to extract maximum power out of SPV under different irradiation levels, while the grid interfacing inverter is utilized to evacuate the active power and feed it into grid at synchronized voltage and frequency. Moreover, the grid interfacing inverter is also controlled to sort out the issues related to power quality by compensating the reactive power and harmonics current component of nearby load at point of common coupling. Besides, detailed modeling of various component utilized in proposed system is also presented. Finally, extensive simulations have been performed under different irradiation levels with various kinds of load to validate the aforementioned claims. The overall system design and simulation have been performed by using Sim Power System toolbox available in the library of MATLAB.

  13. Comparative Study of Standards for Grid-Connected Wind Power Plant in China and the U.S.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, Wenzhong; Tian, Tian; Muljadi, Eduard

    2015-10-06

    The rapid deployment of wind power has made grid integration and operational issues focal points in industry discussions and research. Compliance with grid connection standards for wind power plants (WPP) is crucial to ensuring the safe and stable operation of the electric power grid. The standards for grid-connected WPPs in China and the United States are compared in this paper to facilitate further improvements to the standards and enhance the development of wind power equipment. Detailed analyses in power quality, low-voltage ride-through capability, active power control, reactive power control, voltage control, and wind power forecasting are provided to enhance themore » understanding of grid codes in the two largest markets of wind power.« less

  14. Consistently high sports/exercise activity is associated with better sleep quality, continuity and depth in midlife women: the SWAN sleep study.

    PubMed

    Kline, Christopher E; Irish, Leah A; Krafty, Robert T; Sternfeld, Barbara; Kravitz, Howard M; Buysse, Daniel J; Bromberger, Joyce T; Dugan, Sheila A; Hall, Martica H

    2013-09-01

    To examine relationships between different physical activity (PA) domains and sleep, and the influence of consistent PA on sleep, in midlife women. Cross-sectional. Community-based. 339 women in the Study of Women's Health Across the Nation Sleep Study (52.1 ± 2.1 y). None. Sleep was examined using questionnaires, diaries and in-home polysomnography (PSG). PA was assessed in three domains (Active Living, Household/Caregiving, Sports/Exercise) using the Kaiser Physical Activity Survey (KPAS) up to 4 times over 6 years preceding the sleep assessments. The association between recent PA and sleep was evaluated using KPAS scores immediately preceding the sleep assessments. The association between the historical PA pattern and sleep was examined by categorizing PA in each KPAS domain according to its pattern over the 6 years preceding sleep assessments (consistently low, inconsistent/consistently moderate, or consistently high). Greater recent Sports/Exercise activity was associated with better sleep quality (diary "restedness" [P < 0.01]), greater sleep continuity (diary sleep efficiency [SE; P = 0.02]) and depth (higher NREM delta electroencephalographic [EEG] power [P = 0.04], lower NREM beta EEG power [P < 0.05]), and lower odds of insomnia diagnosis (P < 0.05). Consistently high Sports/Exercise activity was also associated with better Pittsburgh Sleep Quality Index scores (P = 0.02) and higher PSG-assessed SE (P < 0.01). Few associations between sleep and Active Living or Household/Caregiving activity (either recent or historical pattern) were noted. Consistently high levels of recreational physical activity, but not lifestyle- or household-related activity, are associated with better sleep in midlife women. Increasing recreational physical activity early in midlife may protect against sleep disturbance in this population.

  15. Highlighting the harmonic regime generated by electric locomotives equipped with DC motors

    NASA Astrophysics Data System (ADS)

    Baciu, I.; Cunţan, C. D.

    2018-01-01

    The paper presents the results of measurements made using the C.A. 8334 power quality analyzer on an electric locomotive equipped with DC motors. We carried out determinations of the current-voltage regime using a locomotive motor. The harmonic regime of the other motors being identical to the analysed one, we could easily deduce the effects caused by the entire locomotive. The data measured with the analyzer were firstly transferred into a computer system using the Qualistar software, followed by data processing in Excel, enabling therefore a graphical representation of the characteristic parameters of power quality. Based on the acquired data, we determined the power factor, as well as the active, reactive and apparent power. The measurements revealed high values of the current harmonics, fact that required some measures to be taken for reducing the values of these harmonics. For this, we ran a simulation using the PSCAD/EMTDC software, by introducing LC filters in tune with the harmonic frequencies. The result was a significant reduction in the harmonic regime, either in the harmonics values or the power factor and reactive power.

  16. Design of Passive Power Filter for Hybrid Series Active Power Filter using Estimation, Detection and Classification Method

    NASA Astrophysics Data System (ADS)

    Swain, Sushree Diptimayee; Ray, Pravat Kumar; Mohanty, K. B.

    2016-06-01

    This research paper discover the design of a shunt Passive Power Filter (PPF) in Hybrid Series Active Power Filter (HSAPF) that employs a novel analytic methodology which is superior than FFT analysis. This novel approach consists of the estimation, detection and classification of the signals. The proposed method is applied to estimate, detect and classify the power quality (PQ) disturbance such as harmonics. This proposed work deals with three methods: the harmonic detection through wavelet transform method, the harmonic estimation by Kalman Filter algorithm and harmonic classification by decision tree method. From different type of mother wavelets in wavelet transform method, the db8 is selected as suitable mother wavelet because of its potency on transient response and crouched oscillation at frequency domain. In harmonic compensation process, the detected harmonic is compensated through Hybrid Series Active Power Filter (HSAPF) based on Instantaneous Reactive Power Theory (IRPT). The efficacy of the proposed method is verified in MATLAB/SIMULINK domain and as well as with an experimental set up. The obtained results confirm the superiority of the proposed methodology than FFT analysis. This newly proposed PPF is used to make the conventional HSAPF more robust and stable.

  17. Experimental investigation of the transverse modal instabilities onset in high power fully-aperiodic-large-pitch fiber lasers

    NASA Astrophysics Data System (ADS)

    Malleville, Marie-Alicia; Benoît, Aurélien; Dauliat, Romain; Leconte, Baptiste; Darwich, Dia; du Jeu, Rémi; Jamier, Raphaël.; Schwuchow, Anka; Schuster, Kay; Roy, Philippe

    2018-02-01

    Over the last decade, significant work has been carried out in order to increase the energy/peak power provided by fiber lasers. Indeed, new microstructured fibers with large (or very large) mode area cores (LMA) such as Distributed Mode Filtering (DMF) fibers and Large-Pitch Fibers (LPF) have been developed to address this concern. These technologies have allowed diffraction-limited emission with core diameters higher than 80 μm, and have state-of-the-art performances in terms of pulse energy or peak power while keeping an excellent spatial beam quality. Although these fibers were designed to reach high power levels while maintaining a single transverse mode propagation, power scaling becomes quickly limited by the onset of transverse modal instabilities (TMI). This effect suddenly arises when a certain average power threshold is exceeded, drastically degrading the emitted beam quality. In this work, we investigate the influence of the core dimensions and the refractive index mismatch between the active core and the background cladding material, on the TMI power threshold in rod-type Fully-Aperiodic-LPF. This fiber structure was specifically designed to enhance the higher-order modes (HOMs) delocalization out of the gain region and thus push further the onset of modal instabilities. Using a 400W pump diode at 976 nm, the power scaling, as well as the spatial beam quality and its temporal behavior were investigated in laser configuration, which theoretically provides a lower TMI power threshold than the amplifier one due to the lack of selective excitation of the fundamental mode.

  18. A Hearing-Based, Frequency Domain Sound Quality Model for Combined Aerodynamic and Power Transmission Response with Application to Rotorcraft Interior Noise

    NASA Astrophysics Data System (ADS)

    Sondkar, Pravin B.

    The severity of combined aerodynamics and power transmission response in high-speed, high power density systems such as a rotorcraft is still a major cause of annoyance in spite of recent advancement in passive, semi-active and active control. With further increase in the capacity and power of this class of machinery systems, the acoustic noise levels are expected to increase even more. To achieve further improvements in sound quality, a more refined understanding of the factors and attributes controlling human perception is needed. In the case of rotorcraft systems, the perceived quality of the interior sound field is a major determining factor of passenger comfort. Traditionally, this sound quality factor is determined by measuring the response of a chosen set of juries who are asked to compare their qualitative reactions to two or more sounds based on their subjective impressions. This type of testing is very time-consuming, costly, often inconsistent, and not useful for practical design purposes. Furthermore, there is no known universal model for sound quality. The primary aim of this research is to achieve significant improvements in quantifying the sound quality of combined aerodynamic and power transmission response in high-speed, high power density machinery systems such as a rotorcraft by applying relevant objective measures related to the spectral characteristics of the sound field. Two models have been proposed in this dissertation research. First, a classical multivariate regression analysis model based on currently known sound quality metrics as well some new metrics derived in this study is presented. Even though the analysis resulted in the best possible multivariate model as a measure of the acoustic noise quality, it lacks incorporation of human judgment mechanism. The regression model can change depending on specific application, nature of the sounds and types of juries used in the study. Also, it predicts only the averaged preference scores and does not explain why two jury members differ in their judgment. To address the above shortcoming of applying regression analysis, a new human judgment model is proposed to further improve the ability to predict the degree of subjective annoyance. The human judgment model involves extraction of subjective attributes and their values using a proposed artificial jury processor. In this approach, a set of ear transfer functions are employed to compute the characteristics of sound pressure waves as perceived subjectively by human. The resulting basilar membrane displacement data from this proposed model is then applied to analyze the attribute values. Using this proposed human judgment model, the human judgment mechanism, which is highly sophisticated, will be examined. Since the human judgment model is essentially based on jury attributes that are not expected to change significantly with application or nature of the sound field, it gives a more common basis to evaluate sound quality. This model also attempts to explain the inter-juror differences in opinion, which is critical in understanding the variability in human response.

  19. Neodymium-doped phosphate fiber lasers with an all-solid microstructured inner cladding.

    PubMed

    Zhang, Guang; Zhou, Qinling; Yu, Chunlei; Hu, Lili; Chen, Danping

    2012-06-15

    We report on high-power fiber lasers based on index-guiding, all-solid neodymium-doped (Nd-doped) phosphate photonic crystal fiber (PCF) with a hexagonal-shaped inner cladding. The optimum fiber laser with a 36 cm length active fiber, generated up to 7.92 W output power at 1053 nm, which benefited from a high absorption coefficient for pump power due to its noncircular inner cladding. The guiding properties of the all-solid PCF were also investigated. A stable mode with a donut-shaped profile and a power-dependent laser beam quality have been observed experimentally and analyzed.

  20. Application of power ultrasound on the convective drying of fruits and vegetables: effects on quality.

    PubMed

    Rodríguez, Óscar; Eim, Valeria; Rosselló, Carmen; Femenia, Antoni; Cárcel, Juan A; Simal, Susana

    2018-03-01

    Drying gives rise to products with a long shelf life by reducing the water activity to a level that is sufficiently low to inhibit the growth of microorganisms, enzymatic reactions and other deteriorative reactions. Despite the benefits of this operation, the quality of heat sensitive products is diminished when high temperatures are used. The use of low drying temperatures reduces the heat damage but, because of a longer drying time, oxidation reactions occur and a reduction of the quality is also observed. Thus, drying is a method that lends itself to being intensified. For this reason, alternative techniques are being studied. Power ultrasound is considered as an emerging and promising technology in the food industry. The potential of this technology relies on its ability to accelerate the mass transfer processes in solid-liquid and solid-gas systems. Intensification of the drying process with power ultrasound can be achieved by modifying the product behavior during drying, using pre-treatments such as soaking in a liquid medium assisted acoustically or, during the drying process itself, by applying power ultrasound in the gaseous medium. This review summarises the effects of the application of the power ultrasound on the quality of different dried products, such as fruits and vegetables, when the acoustic energy is intended to intensify the drying process, either when the application is performed before pretreatment or during the drying process. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  1. Control voltage and power fluctuations when connecting wind farms

    NASA Astrophysics Data System (ADS)

    Berinde, Ioan; Bǎlan, Horia; Oros Pop, Teodora Susana

    2015-12-01

    Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve.

  2. Assessment of Power Quality based on Fuzzy Logic and Discrete Wavelet Transform for Nonstationary Disturbances

    NASA Astrophysics Data System (ADS)

    Sinha, Pampa; Nath, Sudipta

    2010-10-01

    The main aspects of power system delivery are reliability and quality. If all the customers of a power system get uninterrupted power through the year then the system is considered to be reliable. The term power quality may be referred to as maintaining near sinusoidal voltage at rated frequency at the consumers end. The power component definitions are defined according to the IEEE Standard 1459-2000 both for single phase and three phase unbalanced systems based on Fourier Transform (FFT). In the presence of nonstationary power quality (PQ) disturbances results in accurate values due to its sensitivity to the spectral leakage problem. To overcome these limitations the power quality components are calculated using Discrete Wavelet Transform (DWT). In order to handle the uncertainties associated with electric power systems operations fuzzy logic has been incorporated in this paper. A new power quality index has been introduced here which can assess the power quality under nonstationary disturbances.

  3. Examining System-Wide Impacts of Solar PV Control Systems with a Power Hardware-in-the-Loop Platform

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, Tess L.; Fuller, Jason C.; Schneider, Kevin P.

    2014-06-08

    High penetration levels of distributed solar PV power generation can lead to adverse power quality impacts, such as excessive voltage rise, voltage flicker, and reactive power values that result in unacceptable voltage levels. Advanced inverter control schemes have been developed that have the potential to mitigate many power quality concerns. However, local closed-loop control may lead to unintended behavior in deployed systems as complex interactions can occur between numerous operating devices. To enable the study of the performance of advanced control schemes in a detailed distribution system environment, a test platform has been developed that integrates Power Hardware-in-the-Loop (PHIL) withmore » concurrent time-series electric distribution system simulation. In the test platform, GridLAB-D, a distribution system simulation tool, runs a detailed simulation of a distribution feeder in real-time mode at the Pacific Northwest National Laboratory (PNNL) and supplies power system parameters at a point of common coupling. At the National Renewable Energy Laboratory (NREL), a hardware inverter interacts with grid and PV simulators emulating an operational distribution system. Power output from the inverters is measured and sent to PNNL to update the real-time distribution system simulation. The platform is described and initial test cases are presented. The platform is used to study the system-wide impacts and the interactions of inverter control modes—constant power factor and active Volt/VAr control—when integrated into a simulated IEEE 8500-node test feeder. We demonstrate that this platform is well-suited to the study of advanced inverter controls and their impacts on the power quality of a distribution feeder. Additionally, results are used to validate GridLAB-D simulations of advanced inverter controls.« less

  4. 77 FR 77069 - Commission Information Collection Activities (FERC-730); Comment Request; Extension

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-31

    ... reliability and to reduce the cost of delivered power by reducing transmission congestion. Order No. 679 also... information, including the validity of the methodology and assumptions used; (3) ways to enhance the quality...

  5. Fault Analysis in a Grid Integrated DFIG Based Wind Energy System with NA CB_P Circuit for Ridethrough Capability and Power Quality Improvement

    NASA Astrophysics Data System (ADS)

    Swain, Snehaprava; Ray, Pravat Kumar

    2016-12-01

    In this paper a three phase fault analysis is done on a DFIG based grid integrated wind energy system. A Novel Active Crowbar Protection (NACB_P) system is proposed to enhance the Fault-ride through (FRT) capability of DFIG both for symmetrical as well as unsymmetrical grid faults. Hence improves the power quality of the system. The protection scheme proposed here is designed with a capacitor in series with the resistor unlike the conventional Crowbar (CB) having only resistors. The major function of the capacitor in the protection circuit is to eliminate the ripples generated in the rotor current and to protect the converter as well as the DC-link capacitor. It also compensates reactive power required by the DFIG during fault. Due to these advantages the proposed scheme enhances the FRT capability of the DFIG and also improves the power quality of the whole system. Experimentally the fault analysis is done on a 3hp slip ring induction generator and simulation results are carried out on a 1.7 MVA DFIG based WECS under different types of grid faults in MATLAB/Simulation and functionality of the proposed scheme is verified.

  6. High Power Particle Beams and Pulsed Power for Industrial Applications

    NASA Astrophysics Data System (ADS)

    Bluhm, Hansjoachim; An, Wladimir; Engelko, Wladimir; Giese, Harald; Frey, Wolfgang; Heinzel, Annette; Hoppé, Peter; Mueller, Georg; Schultheiss, Christoph; Singer, Josef; Strässner, Ralf; Strauß, Dirk; Weisenburger, Alfons; Zimmermann, Fritz

    2002-12-01

    Several industrial scale projects with economic and ecologic potential are presently emanating from research and development in the fields of high power particle beams and pulsed power in Europe. Material surface modifications with large area pulsed electron beams are used to protect high temperature gas turbine blades and steel structures in Pb/Bi cooled accelerator driven nuclear reactor systems against oxidation and corrosion respectively. Channel spark electron beams are applied to deposit bio-compatible or bio-active layers on medical implants. Cell membranes are perforated with strong pulsed electric fields to extract nutritive substances or raw materials from the cells and to kill bacteria for sterilization of liquids. Eletrodynamic fragmentation devices are developed to reutilize concrete aggregates for the production of high quality secondary concrete. All activities have a large potential to contribute to a more sustainable economy.

  7. An evaluation method of power quality about electrified railways connected to power grid based on PSCAD/EMTDC

    NASA Astrophysics Data System (ADS)

    Liang, Weibin; Ouyang, Sen; Huang, Xiang; Su, Weijian

    2017-05-01

    The existing modeling process of power quality about electrified railways connected to power grid is complicated and the simulation scene is incomplete, so this paper puts forward a novel evaluation method of power quality based on PSCAD/ETMDC. Firstly, a model of power quality about electrified railways connected to power grid is established, which is based on testing report or measured data. The equivalent model of electrified locomotive contains power characteristic and harmonic characteristic, which are substituted by load and harmonic source. Secondly, in order to make evaluation more complete, an analysis scheme has been put forward. The scheme uses a combination of three-dimensions of electrified locomotive, which contains types, working conditions and quantity. At last, Shenmao Railway is taken as example to evaluate the power quality at different scenes, and the result shows electrified railways connected to power grid have significant effect on power quality.

  8. Development of an expert system for power quality advisement using CLIPS 6.0

    NASA Technical Reports Server (NTRS)

    Chandrasekaran, A.; Sarma, P. R. R.; Sundaram, Ashok

    1994-01-01

    Proliferation of power electronic devices has brought in its wake both deterioration in and demand for quality power supply from the utilities. The power quality problems become apparent when the user's equipment or systems maloperate or fail. Since power quality concerns arise from a wide variety of sources and the problem fixes are better achieved from the expertise of field engineers, development of an expert system for power quality advisement seems to be a very attractive and cost-effective solution for utility applications. An expert system thus developed gives an understanding of the adverse effects of power quality related problems on the system and could help in finding remedial solutions. The paper reports the design of a power quality advisement expert system being developed using CLIPS 6.0. A brief outline of the power quality concerns is first presented. A description of the knowledge base is next given and details of actual implementation include screen output from the program.

  9. Predicting soil quality indices with near infrared analysis in a wildfire chronosequence.

    PubMed

    Cécillon, Lauric; Cassagne, Nathalie; Czarnes, Sonia; Gros, Raphaël; Vennetier, Michel; Brun, Jean-Jacques

    2009-01-15

    We investigated the power of near infrared (NIR) analysis for the quantitative assessment of soil quality in a wildfire chronosequence. The effect of wildfire disturbance and soil engineering activity of earthworms on soil organic matter quality was first assessed with principal component analysis of NIR spectra. Three soil quality indices were further calculated using an adaptation of the method proposed by Velasquez et al. [Velasquez, E., Lavelle, P., Andrade, M. GISQ, a multifunctional indicator of soil quality. Soil Biol Biochem 2007; 39: 3066-3080.], each one addressing an ecosystem service provided by soils: organic matter storage, nutrient supply and biological activity. Partial least squares regression models were developed to test the predicting ability of NIR analysis for these soil quality indices. All models reached coefficients of determination above 0.90 and ratios of performance to deviation above 2.8. This finding provides new opportunities for the monitoring of soil quality, using NIR scanning of soil samples.

  10. Characterization of Nighttime Light Variability Over the Southeastern United States

    NASA Technical Reports Server (NTRS)

    Cole, Tony A.; Molthan, Andrew L.; Schultz, Lori A.

    2016-01-01

    City lights provide indications of human activity at night. Nighttime satellite imagery offers daily snapshots of this activity. With calibrated, science-quality imagery, long-term monitoring can also be achieved. The degree to which city lights fluctuate, however, is not well known. For the application of detecting power outages, this degree of variability is crucial for assessing reductions to city lights based on historical trends. Eight southeastern U.S. cities are analyzed to understand the relationship between emission variability and several population centers. A preliminary, example case power outage study is also discussed as a transition into future work.

  11. Immunological parameters in elderly women: correlations with aerobic power, muscle strength and mood state.

    PubMed

    Raso, Vagner; Natale, Valéria Maria; Duarte, Alberto José da Silva; Greve, Júlia Maria D'Andrea; Shephard, Roy J

    2012-05-01

    Our objective was to relate immunological data for healthy but sedentary elderly women to aerobic power, strength, and mood state. We measured peak aerobic power and one-repetition maximum strength along with mood (depression and fatigue), quality of life and carbohydrate intake on 42 women aged 60-77 years. Standard immunological techniques determined natural killer cell count and cytotoxic activity (NKCA), proliferative responses to phytohemaglutinin and OKT(3), various lymphocyte subpopulations (CD3(+), CD3(-)CD19(+), CD56(+), CD4(+), CD8(+), CD56(dim) and CD56(bright)), and markers of activation, maturation, down-regulation and susceptibility to apoptosis (CD25(+), CD28(+), CD45RA(+), CD45RO(+), CD69(+), CD95(+), HLA-DR(+)). Correlations of immune parameters with aerobic power and strength were very similar for absolute and relative immunological data. In the group as a whole, the only correlation with aerobic power was -0.35 (relative CD4(+)CD69(+) count), but in subjects with values <22.6 mL kg(-1)min(-1) correlations ranged from -0.57 (relative CD4(+)CD45RO(+)) to 0.92 (absolute CD56(dim)HLA-DR(+)). In terms of muscle strength, univariate correlation coefficients ranged from -0.34 (relative and absolute CD3(+)CD4(+)CD8(+)) to +0.48 (absolute CD3(+)HLA-DR(+)) and +0.50 (absolute CD8(+)CD45RA(+)CD45RO(+)). Neither NKCA nor lymphocyte proliferation were correlated with aerobic power or muscle strength. Although mood state and quality of life can sometimes be influenced by an individual's fitness level, our multivariate analyses suggested that depression, fatigue and quality of life were more important determinants of immune profile than our fitness measures. Psychological changes associated with aging may have a substantial adverse effect upon the immune system, and immunological function may be enhanced more by addressing these issues than by focusing upon aerobic or resistance training. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. The Dating Game.

    ERIC Educational Resources Information Center

    Zerger, Monte J.

    1998-01-01

    Presents activities to cultivate the tendency to see special qualities in numbers that can be played on certain calendar days. Includes games on the constant of the day, Fibonacci and golden ratio dates, primes, powers, December 25, and the day of the year. (ASK)

  13. Consistently High Sports/Exercise Activity Is Associated with Better Sleep Quality, Continuity and Depth in Midlife Women: The SWAN Sleep Study

    PubMed Central

    Kline, Christopher E.; Irish, Leah A.; Krafty, Robert T.; Sternfeld, Barbara; Kravitz, Howard M.; Buysse, Daniel J.; Bromberger, Joyce T.; Dugan, Sheila A.; Hall, Martica H.

    2013-01-01

    Study Objectives: To examine relationships between different physical activity (PA) domains and sleep, and the influence of consistent PA on sleep, in midlife women. Design: Cross-sectional. Setting: Community-based. Participants: 339 women in the Study of Women's Health Across the Nation Sleep Study (52.1 ± 2.1 y). Interventions: None. Measurements and Results: Sleep was examined using questionnaires, diaries and in-home polysomnography (PSG). PA was assessed in three domains (Active Living, Household/Caregiving, Sports/Exercise) using the Kaiser Physical Activity Survey (KPAS) up to 4 times over 6 years preceding the sleep assessments. The association between recent PA and sleep was evaluated using KPAS scores immediately preceding the sleep assessments. The association between the historical PA pattern and sleep was examined by categorizing PA in each KPAS domain according to its pattern over the 6 years preceding sleep assessments (consistently low, inconsistent/consistently moderate, or consistently high). Greater recent Sports/Exercise activity was associated with better sleep quality (diary “restedness” [P < 0.01]), greater sleep continuity (diary sleep efficiency [SE; P = 0.02]) and depth (higher NREM delta electroencephalographic [EEG] power [P = 0.04], lower NREM beta EEG power [P < 0.05]), and lower odds of insomnia diagnosis (P < 0.05). Consistently high Sports/Exercise activity was also associated with better Pittsburgh Sleep Quality Index scores (P = 0.02) and higher PSG-assessed SE (P < 0.01). Few associations between sleep and Active Living or Household/Caregiving activity (either recent or historical pattern) were noted. Conclusion: Consistently high levels of recreational physical activity, but not lifestyle- or household-related activity, are associated with better sleep in midlife women. Increasing recreational physical activity early in midlife may protect against sleep disturbance in this population. Citation: Kline CE; Irish LA; Krafty RT; Sternfeld B; Kravitz HM; Buysse DJ; Bromberger JT; Dugan SA; Hall MH. Consistently high sports/exercise activity is associated with better sleep quality, continuity and depth in midlife women: the SWAN Sleep Study. SLEEP 2013;36(9):1279-1288. PMID:23997360

  14. Examining System-Wide Impacts of Solar PV Control Systems with a Power Hardware-in-the-Loop Platform

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, Tess L.; Fuller, Jason C.; Schneider, Kevin P.

    2014-10-11

    High penetration levels of distributed solar PV power generation can lead to adverse power quality impacts such as excessive voltage rise, voltage flicker, and reactive power values that result in unacceptable voltage levels. Advanced inverter control schemes have been proposed that have the potential to mitigate many power quality concerns. However, closed-loop control may lead to unintended behavior in deployed systems as complex interactions can occur between numerous operating devices. In order to enable the study of the performance of advanced control schemes in a detailed distribution system environment, a Hardware-in-the-Loop (HIL) platform has been developed. In the HIL system,more » GridLAB-D, a distribution system simulation tool, runs in real-time mode at the Pacific Northwest National Laboratory (PNNL) and supplies power system parameters at a point of common coupling to hardware located at the National Renewable Energy Laboratory (NREL). Hardware inverters interact with grid and PV simulators emulating an operational distribution system and power output from the inverters is measured and sent to PNNL to update the real-time distribution system simulation. The platform is described and initial test cases are presented. The platform is used to study the system-wide impacts and the interactions of controls applied to inverters that are integrated into a simulation of the IEEE 8500-node test feeder, with inverters in either constant power factor control or active volt/VAR control. We demonstrate that this HIL platform is well-suited to the study of advanced inverter controls and their impacts on the power quality of a distribution feeder. Additionally, the results from HIL are used to validate GridLAB-D simulations of advanced inverter controls.« less

  15. Adaptive Harmonic Detection Control of Grid Interfaced Solar Photovoltaic Energy System with Power Quality Improvement

    NASA Astrophysics Data System (ADS)

    Singh, B.; Goel, S.

    2015-03-01

    This paper presents a grid interfaced solar photovoltaic (SPV) energy system with a novel adaptive harmonic detection control for power quality improvement at ac mains under balanced as well as unbalanced and distorted supply conditions. The SPV energy system is capable of compensation of linear and nonlinear loads with the objectives of load balancing, harmonics elimination, power factor correction and terminal voltage regulation. The proposed control increases the utilization of PV infrastructure and brings down its effective cost due to its other benefits. The adaptive harmonic detection control algorithm is used to detect the fundamental active power component of load currents which are subsequently used for reference source currents estimation. An instantaneous symmetrical component theory is used to obtain instantaneous positive sequence point of common coupling (PCC) voltages which are used to derive inphase and quadrature phase voltage templates. The proposed grid interfaced PV energy system is modelled and simulated in MATLAB Simulink and its performance is verified under various operating conditions.

  16. Comparison of Standards and Technical Requirements of Grid-Connected Wind Power Plants in China and the United States

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, David Wenzhong; Muljadi, Eduard; Tian, Tian

    The rapid deployment of wind power has made grid integration and operational issues focal points in industry discussions and research. Compliance with grid connection standards for wind power plants (WPPs) is crucial to ensuring the reliable and stable operation of the electric power grid. This report compares the standards for grid-connected WPPs in China to those in the United States to facilitate further improvements in wind power standards and enhance the development of wind power equipment. Detailed analyses of power quality, low-voltage ride-through capability, active power control, reactive power control, voltage control, and wind power forecasting are provided to enhancemore » the understanding of grid codes in the two largest markets of wind power. This study compares WPP interconnection standards and technical requirements in China to those in the United States.« less

  17. 1.3 μm wavelength vertical cavity surface emitting laser fabricated by orientation-mismatched wafer bonding: A prospect for polarization control

    NASA Astrophysics Data System (ADS)

    Okuno, Yae L.; Geske, Jon; Gan, Kian-Giap; Chiu, Yi-Jen; DenBaars, Steven P.; Bowers, John E.

    2003-04-01

    We propose and demonstrate a long-wavelength vertical cavity surface emitting laser (VCSEL) which consists of a (311)B InP-based active region and (100) GaAs-based distributed Bragg reflectors (DBRs), with an aim to control the in-plane polarization of output power. Crystal growth on (311)B InP substrates was performed under low-migration conditions to achieve good crystalline quality. The VCSEL was fabricated by wafer bonding, which enables us to combine different materials regardless of their lattice and orientation mismatch without degrading their quality. The VCSEL was polarized with a power extinction ratio of 31 dB.

  18. Two-step activation of paper batteries for high power generation: design and fabrication of biofluid- and water-activated paper batteries

    NASA Astrophysics Data System (ADS)

    Lee, Ki Bang

    2006-11-01

    Two-step activation of paper batteries has been successfully demonstrated to provide quick activation and to supply high power to credit card-sized biosystems on a plastic chip. A stack of a magnesium layer (an anode), a fluid guide (absorbent paper), a highly doped filter paper with copper chloride (a cathode) and a copper layer as a current collector is laminated between two transparent plastic films into a high power biofluid- and water-activated battery. The battery is activated by two-step activation: (1) after placing a drop of biofluid/water-based solution on the fluid inlet, the surface tension first drives the fluid to soak the fluid guide; (2) the fluid in the fluid guide then penetrates into the heavily doped filter paper with copper chloride to start the battery reaction. The fabricated half credit card-sized battery was activated by saliva, urine and tap water and delivered a maximum voltage of 1.56 V within 10 s after activation and a maximum power of 15.6 mW. When 10 kΩ and 1 KΩ loads are used, the service time with water, urine and saliva is measured as more than 2 h. An in-series battery of 3 V has been successfully tested to power two LEDs (light emitting diodes) and an electric driving circuit. As such, this high power paper battery could be integrated with on-demand credit card-sized biosystems such as healthcare test kits, biochips, lab-on-a-chip, DNA chips, protein chips or even test chips for water quality checking or chemical checking.

  19. Development of Multi-Functional Voltage Restore System

    NASA Astrophysics Data System (ADS)

    Suzuki, Satoshi; Ueda, Yoshinobu; Koganezawa, Takehisa; Ogihara, Yoshinori; Mori, Kenjiro; Fukazu, Naoaki

    Recently, with the dawn of the electric deregulation, the installation of distributed generation with power electronics device has grown. This current causes a greater concern of power quality, primarily voltage disturbance for power companies, and their interest in power quality is peaking. Utilities are also interested in keeping their customers satisfied, as well as keeping them on-line and creating more revenue for the utility. As a countermeasure against the above surroundings, a variety type of devices based on power electronics has been developed to protect customers' load from power line voltage disturbance. One of them is the series type voltage restore. The series device is an active device, designed to provide a pure sinusoidal load voltage at all times, correcting voltage disturbance. Series type device compensates for voltage anomalies by inserting the ‘missing’ voltage onto the line through insertion transformer and inverter. This paper shows the setting guideline of target level to compensate voltage disturbance, that is, voltage dip, voltage harmonics, voltage imbalance and voltage flicker, and the design approach of the prototype of series voltage restores to accomplish the required compensation level. The prototype system gives satisfactory compensation performance through evaluation tests, which confirm the validity and effectiveness of the system.

  20. Pilot evaluation of electricity-reliability and power-quality monitoring in California's Silicon Valley with the I-Grid(R) system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eto, Joseph; Divan, Deepak; Brumsickle, William

    2004-02-01

    Power-quality events are of increasing concern for the economy because today's equipment, particularly computers and automated manufacturing devices, is susceptible to these imperceptible voltage changes. A small variation in voltage can cause this equipment to shut down for long periods, resulting in significant business losses. Tiny variations in power quality are difficult to detect except with expensive monitoring equipment used by trained technicians, so many electricity customers are unaware of the role of power-quality events in equipment malfunctioning. This report describes the findings from a pilot study coordinated through the Silicon Valley Manufacturers Group in California to explore the capabilitiesmore » of I-Grid(R), a new power-quality monitoring system. This system is designed to improve the accessibility of power-quality in formation and to increase understanding of the growing importance of electricity reliability and power quality to the economy. The study used data collected by I-Grid sensors at seven Silicon Valley firms to investigate the impacts of power quality on individual study participants as well as to explore the capabilities of the I-Grid system to detect events on the larger electricity grid by means of correlation of data from the sensors at the different sites. In addition, study participants were interviewed about the value they place on power quality, and their efforts to address electricity-reliability and power-quality problems. Issues were identified that should be taken into consideration in developing a larger, potentially nationwide, network of power-quality sensors.« less

  1. Design of Interline Unified Power Quality Conditioner for Power Quality Disturbances using Simulink

    NASA Astrophysics Data System (ADS)

    Kumaraswamy, G.; Reddy, Y. Rajasekhar; Harikrishna, Ch.

    2012-10-01

    Proliferation of electronic equipment in commercial and industrial processes has resulted in increasingly sensitive electrical loads to be fed from power distribution system which introduce contamination to voltage and current waveforms at the point of common coupling of industrial loads. The unified power quality conditioner (UPQC) is connected between two different feeders (lines), hence this method of connection of the UPQC is called as Interline UPQC (IUPQC).This paper proposes a new connection for a UPQC to improve the power quality of two feeders in a distribution system. Interline Unified Power Quality Conditioner (IUPQC), specifically aims at the integration of series VSC and Shunt VSC to provide high quality power supply by means of voltage sag/swell compensation, harmonic elimination and power factor correction in a power distribution network, so that improved power quality can be made available at the point of common coupling. The structure, control and capability of the IUPQC are discussed in this paper. The efficiency of the proposed configuration has been verified through simulation using MATLAB/ SIMULINK.

  2. Automated recognition system for power quality disturbances

    NASA Astrophysics Data System (ADS)

    Abdelgalil, Tarek

    The application of deregulation policies in electric power systems has resulted in the necessity to quantify the quality of electric power. This fact highlights the need for a new monitoring strategy which is capable of tracking, detecting, classifying power quality disturbances, and then identifying the source of the disturbance. The objective of this work is to design an efficient and reliable power quality monitoring strategy that uses the advances in signal processing and pattern recognition to overcome the deficiencies that exist in power quality monitoring devices. The purposed monitoring strategy has two stages. The first stage is to detect, track, and classify any power quality violation by the use of on-line measurements. In the second stage, the source of the classified power quality disturbance must be identified. In the first stage, an adaptive linear combiner is used to detect power quality disturbances. Then, the Teager Energy Operator and Hilbert Transform are utilized for power quality event tracking. After the Fourier, Wavelet, and Walsh Transforms are employed for the feature extraction, two approaches are then exploited to classify the different power quality disturbances. The first approach depends on comparing the disturbance to be classified with a stored set of signatures for different power quality disturbances. The comparison is developed by using Hidden Markov Models and Dynamic Time Warping. The second approach depends on employing an inductive inference to generate the classification rules directly from the data. In the second stage of the new monitoring strategy, only the problem of identifying the location of the switched capacitor which initiates the transients is investigated. The Total Least Square-Estimation of Signal Parameters via Rotational Invariance Technique is adopted to estimate the amplitudes and frequencies of the various modes contained in the voltage signal measured at the facility entrance. After extracting the amplitudes and frequencies, an Artificial Neural Network is employed to identify the switched capacitor by using amplitudes and frequencies extracted from the transient signal. The new algorithms for detecting, tracking, and classifying power quality disturbances demonstrate the potential for further development of a fully automated recognition system for the assessment of power quality. This is possible because the implementation of the proposed algorithms for the power quality monitoring device becomes a straight forward process by modifying the device software.

  3. Affective Evaluations of and Reactions to Exterior and Interior Vehicle Auditory Quality

    NASA Astrophysics Data System (ADS)

    Västfjäll, D.; Gulbol, M.-A.; Kleiner, M.; Gärling, T.

    2002-08-01

    Affective reactions to and evaluations of auditory stimuli are fundamental components of human perception. In three experiments, participants rated their affective reactions (how pleasant I feel) and preferences for these affective reactions (how much I like the way I feel) as well as affective evaluations (how pleasant the sound is) to interior and exterior binaurally recorded vehicle sounds varying in physical properties. Consistent with previous research, it was found that the orthogonal affect dimensions of valence (unpleasant-pleasant) and arousal or activation (deactivation-activation) discriminated between affective reactions induced by the different qualities of the sounds. Moreover, preference for affective reactions was related to both valence and activation. Affective evaluations (powerful-powerless/passive-active and unpleasant-pleasant) correlated significantly with affective reactions to the same sounds in both within-subjects and between-subjects designs. Standard sound quality metrics derived from the sounds correlated, however, poorly with the affective ratings of interior sounds and only moderately with affective ratings of exterior sounds. Taken together, the results suggest that affect is an important component in product auditory quality optimization.

  4. A Logistic Life Cycle Cost-Benefit Analysis of Power Quality Management in the Avionics Repair Facility

    DTIC Science & Technology

    1998-06-01

    quality management can have on the intermediate level of maintenance. Power quality management is a preventative process that focuses on identifying and correcting problems that cause bad power. Using cost-benefit analysis we compare the effects of implementing a power quality management program at AIMD Lemoore and AIMD Fallon. The implementation of power quality management can result in wide scale logistical support changes in regards to the life cycle costs of maintaining the DoD’s current inventory

  5. Actively Q-switched laser with novel Nd:YAG/YAG polygonal active-mirror

    NASA Astrophysics Data System (ADS)

    Lang, Ye; Chen, Yanzhong; Ge, Wenqi; He, Jianguo; Zhang, Hongbo; Liao, Lifen; Xin, Jianguo; Zhang, Jian; Fan, Zhongwei

    2018-03-01

    In this work, we demonstrate an efficient actively Q-switched laser based on a novel crystal Nd:YAG/YAG polygonal active mirror. A passively cooled crystal Nd:YAG/YAG polygonal active mirror with an end pump scheme was used as the gain medium. For the overlap between the TEM00 laser mode and large gain profile, a cavity was carefully designed with a large fundamental mode volume. With a maximum absorbed power of 3.1 W, a 685 mW average output power with a pulse repetition of 5 kHz was attained, and the corresponding optical-optical and slope efficiency were 22.1% and 27.7%, respectively. The pulse width was 133.9 ns. The beam quality (M 2) was 1.561 in the horizontal direction and 1.261 in the vertical direction.

  6. High-power thulium-doped fiber laser in an all-fiber configuration

    NASA Astrophysics Data System (ADS)

    Baravets, Yauhen; Todorov, Filip; Honzatko, Pavel

    2016-12-01

    High-power Tm-doped fiber lasers are greatly suitable for various applications, such as material processing, medicine, environmental monitoring and topography. In this work we present an all-fiber narrowband CW laser in near fundamental mode operation based on a Tm-doped double-clad active fiber pumped by 793 nm laser diodes with a central wavelength stabilized at 2039 nm by a fiber Bragg grating. The achieved output power is 60 W with a slope efficiency of 46%. The measured beam quality factor is less than 1.4. Further increasing of the output power is possible using various power scaling techniques, for example, coherent combination of several Tm-doped fiber lasers. The developed fiber laser could be employed for welding, cutting and marking of thermoplastics in industry, minimally invasive surgery in medicine or sensors in lidar systems. Future improvements of thulium fiber lasers are possible due to the extremely wide gain-bandwidth of the active medium and the rapid growth of 2-μm fiber components production.

  7. Effect of Partial Replacement of Wheat Flour with High Quality Cassava Flour on the Chemical Composition, Antioxidant Activity, Sensory Quality, and Microbial Quality of Bread

    PubMed Central

    Eleazu, Chinedum; Eleazu, Kate; Aniedu, Chinyere; Amajor, John; Ikpeama, Ahamefula; Ebenzer, Ike

    2014-01-01

    In the current study, wheat flour was mixed with high quality cassava flour (HQCF) in several ratios: 90:10, 80:20, 70:30, and 60:40, and used to prepare 10%, 20%, 30%, and 40% National Root Crops Research Institute (NRCRI) cassava bread, respectively. 100% wheat bread was prepared as a control (100% wheat bread). Five bread samples were prepared per group. Antioxidant assays [i.e., 2,2-diphenyl- 1-picrylhydrazyl radical (DPPH) scavenging assay, reducing power assay] revealed that the bread samples had considerable antioxidant capacities. Substitution of wheat flour with HQCF at various concentrations resulted in dose dependent decreases in the mineral and protein contents of the resulting bread samples. The crude fiber content of the bread samples was minimal, while the carbohydrate content of the bread samples ranged from 43.86% to 48.64%. A 20% substitution of wheat flour with HQCF yielded bread samples with a general acceptability that was comparable to that of 100% wheat bread. The mean bacteria counts of the bread samples ranged from 2.0×103 CFU/mL to 1.4×104 CFU/mL, while the fungal counts ranged from 0 CFU/mL to 3×103 CFU/mL. There was a positive correlation between the DPPH antioxidant activities and the reducing powers of the bread samples (R2=0.871) and a positive correlation between the DPPH antioxidant activities and the flavonoid contents of the bread samples (R2=0.487). The higher microbial load of the NRCRI cassava bread samples indicates that these bread samples may have a shorter shelf life than the 100% wheat bread. The significant positive correlation between total flavonoid content and reducing power (R2=0.750) suggests that the flavonoids present in the lipophilic fractions of the bread samples could be responsible for the reductive capacities of the bread samples. PMID:25054110

  8. A new approach to power quality and electricity reliability monitoring-case study illustrations of the capabilities of the I-GridTM system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Divan, Deepak; Brumsickle, William; Eto, Joseph

    2003-04-01

    This report describes a new approach for collecting information on power quality and reliability and making it available in the public domain. Making this information readily available in a form that is meaningful to electricity consumers is necessary for enabling more informed private and public decisions regarding electricity reliability. The system dramatically reduces the cost (and expertise) needed for customers to obtain information on the most significant power quality events, called voltage sags and interruptions. The system also offers widespread access to information on power quality collected from multiple sites and the potential for capturing information on the impacts ofmore » power quality problems, together enabling a wide variety of analysis and benchmarking to improve system reliability. Six case studies demonstrate selected functionality and capabilities of the system, including: Linking measured power quality events to process interruption and downtime; Demonstrating the ability to correlate events recorded by multiple monitors to narrow and confirm the causes of power quality events; and Benchmarking power quality and reliability on a firm and regional basis.« less

  9. The air quality and regional climate effects of widespread solar power generation under a changing regulatory environment

    NASA Astrophysics Data System (ADS)

    Millstein, D.; Zhai, P.; Menon, S.

    2011-12-01

    Over the past decade significant reductions of NOx and SOx emissions from coal burning power plants in the U.S. have been achieved due to regulatory action and substitution of new generation towards natural gas and wind power. Low natural gas prices, ever decreasing solar generation costs, and proposed regulatory changes, such as to the Cross State Air Pollution Rule, promise further long-run coal power plant emission reductions. Reduced power plant emissions have the potential to affect ozone and particulate air quality and influence regional climate through aerosol cloud interactions and visibility effects. Here we investigate, on a national scale, the effects on future (~2030) air quality and regional climate of power plant emission regulations in contrast to and combination with policies designed to aggressively promote solar electricity generation. A sophisticated, economic and engineering based, hourly power generation dispatch model is developed to explore the integration of significant solar generation resources (>10% on an energy basis) at various regions across the county, providing detailed estimates of substitution of solar generation for fossil fuel generation resources. Future air pollutant emissions from all sectors of the economy are scaled based on the U.S. Environmental Protection Agency's National Emission Inventory to account for activity changes based on population and economic projections derived from county level U.S. Census data and the Energy Information Administration's Annual Energy Outlook. Further adjustments are made for technological and regulatory changes applicable within various sectors, for example, emission intensity adjustments to on-road diesel trucking due to exhaust treatment and improved engine design. The future year 2030 is selected for the emissions scenarios to allow for the development of significant solar generation resources. A regional climate and air quality model (Weather Research and Forecasting, WRF model) is used to investigate the effects of the various solar generation scenarios given emissions projections that account for changing regulatory environment, economic and population growth, and technological change. The results will help to quantify the potential air quality benefits of promotion of solar electricity generation in regions containing high penetration of coal-fired power generation. Note current national solar incentives that are based only on solar generation capacity. Further investigation of changes to regional climate due to emission reductions of aerosols and relevant precursors will provide insight into the environmental effects that may occur if solar power generation becomes widespread.

  10. Control voltage and power fluctuations when connecting wind farms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berinde, Ioan, E-mail: ioan-berinde@yahoo.com; Bălan, Horia, E-mail: hbalan@mail.utcluj.ro; Oros, Teodora Susana, E-mail: teodoraoros-87@yahoo.com

    2015-12-23

    Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid.more » FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve.« less

  11. Discussion on mass concrete construction of wind turbine generator foundation

    NASA Astrophysics Data System (ADS)

    Shang, Liang; Wu, Chaoxiang; Yin, Xiaoyong

    2018-04-01

    Wind power is one of the main power sources currently. China has rich wind power resources, wind power plants are developed faster and faster. However, China wind power construction started late, which is lack of relevant experience technology. It is easy to produce quality problems. The key to the construction quality of wind power plant is the construction quality of mass concrete construction. Therefore, construction technology and quality control of wind turbine generator foundation mass concrete are discussed and analyzed in the paper.

  12. 10 CFR 830.3 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... research and experimental and analytical laboratory activities, electron microscopes, and X-ray machines... research, test, and power reactors, and critical and pulsed assemblies and any assembly that is designed to... covering a topic such as: quality assurance; maintenance of safety systems; personnel training; conduct of...

  13. Ultra-low-power and robust digital-signal-processing hardware for implantable neural interface microsystems.

    PubMed

    Narasimhan, S; Chiel, H J; Bhunia, S

    2011-04-01

    Implantable microsystems for monitoring or manipulating brain activity typically require on-chip real-time processing of multichannel neural data using ultra low-power, miniaturized electronics. In this paper, we propose an integrated-circuit/architecture-level hardware design framework for neural signal processing that exploits the nature of the signal-processing algorithm. First, we consider different power reduction techniques and compare the energy efficiency between the ultra-low frequency subthreshold and conventional superthreshold design. We show that the superthreshold design operating at a much higher frequency can achieve comparable energy dissipation by taking advantage of extensive power gating. It also provides significantly higher robustness of operation and yield under large process variations. Next, we propose an architecture level preferential design approach for further energy reduction by isolating the critical computation blocks (with respect to the quality of the output signal) and assigning them higher delay margins compared to the noncritical ones. Possible delay failures under parameter variations are confined to the noncritical components, allowing graceful degradation in quality under voltage scaling. Simulation results using prerecorded neural data from the sea-slug (Aplysia californica) show that the application of the proposed design approach can lead to significant improvement in total energy, without compromising the output signal quality under process variations, compared to conventional design approaches.

  14. Comparison of balance of tritium activity in waste water from nuclear power plants and at selected monitoring sites in the Vltava River, Elbe River and Jihlava (Dyje) River catchments in the Czech Republic.

    PubMed

    Hanslík, Eduard; Marešová, Diana; Juranová, Eva; Sedlářová, Barbora

    2017-12-01

    During the routine operation, nuclear power plants discharge waste water containing a certain amount of radioactivity, whose main component is the artificial radionuclide tritium. The amounts of tritium released into the environment are kept within the legal requirements, which minimize the noxious effects of radioactivity, but the activity concentration is well measurable in surface water of the recipient. This study compares amount of tritium activity in waste water from nuclear power plants and the tritium activity detected at selected relevant sites of surface water quality monitoring. The situation is assessed in the catchment of the Vltava and Elbe Rivers, affected by the Temelín Nuclear Power Plant as well as in the Jihlava River catchment (the Danube River catchment respectively), where the waste water of the Dukovany Nuclear Power Plant is discharged. The results show a good agreement of the amount of released tritium stated by the power plant operator and the tritium amount detected in the surface water and highlighted the importance of a robust independent monitoring of tritium discharged from a nuclear power plant which could be carried out by water management authorities. The outputs of independent monitoring allow validating the values reported by a polluter and expand opportunities of using tritium as e.g. tracer. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Influence of the Grain Size on the Properties of CH3NH3PbI3 Thin Films.

    PubMed

    Shargaieva, Oleksandra; Lang, Felix; Rappich, Jörg; Dittrich, Thomas; Klaus, Manuela; Meixner, Matthias; Genzel, Christoph; Nickel, Norbert H

    2017-11-08

    Hybrid perovskites have already shown a huge success as an absorber in solar cells, resulting in the skyrocketing rise in the power conversion efficiency to more than η = 22%. Recently, it has been established that the crystal quality is one of the most important parameters to obtain devices with high efficiencies. However, the influence of the crystal quality on the material properties is not fully understood. Here, the influence of the morphology on electronic properties of CH 3 NH 3 PbI 3 thin films is investigated. Postannealing was used to vary the average grain size continuously from ≈150 to ≈1000 nm. Secondary grain growth is thermally activated with an activation energy of E a = 0.16 eV. The increase in the grain size leads to an enhancement of the photoluminescence, indicating an improvement in the material quality. According to surface photovoltage measurements, the charge-carrier transport length exhibits a linear increase with increasing grain size. The charge-carrier diffusion length is limited by grain boundaries. Moreover, an improved morphology leads to a drastic increase in power conversion efficiency of the devices.

  16. Review of Comprehensive Evaluation Methods for Power Quality and Its Trend in New Generation Energy System

    NASA Astrophysics Data System (ADS)

    Liu, Ruihua; Wang, Rong; Liu, Qunying; Yang, Li; Xi, Chuan; Wang, Wei; Li, Lingzhou; Zhao, Zhoufang; Zhou, Ying

    2018-02-01

    With China’s new energy generation grid connected capacity being in the forefront of the world and the uncertainty of new energy sources, such as wind energy and solar energy, it is be of great significance to study scientific and comprehensive assessment of power quality. On the foundation of analysizing the current power quality index systematically and objectively, the new energy grid power quality analysis method and comprehensive evaluation method, this paper tentatively explored the trend of the new generation of energy system power quality comprehensive evaluation.

  17. Imaging contrast and tip-sample interaction of non-contact amplitude modulation atomic force microscopy with Q-control

    NASA Astrophysics Data System (ADS)

    Shi, Shuai; Guo, Dan; Luo, Jianbin

    2017-10-01

    Active quality factor (Q) exhibits many promising properties in dynamic atomic force microscopy. Energy dissipation and image contrasts are investigated in the non-contact amplitude modulation atomic force microscopy (AM-AFM) with an active Q-control circuit in the ambient air environment. Dissipated power and virial were calculated to compare the highly nonlinear interaction of tip-sample and image contrasts with different Q gain values. Greater free amplitudes and lower effective Q values show better contrasts for the same setpoint ratio. Active quality factor also can be employed to change tip-sample interaction force in non-contact regime. It is meaningful that non-destructive and better contrast images can be realized in non-contact AM-AFM by applying an active Q-control to the dynamic system.

  18. Power and the objectification of social targets.

    PubMed

    Gruenfeld, Deborah H; Inesi, M Ena; Magee, Joe C; Galinsky, Adam D

    2008-07-01

    Objectification has been defined historically as a process of subjugation whereby people, like objects, are treated as means to an end. The authors hypothesized that objectification is a response to social power that involves approaching useful social targets regardless of the value of their other human qualities. Six studies found that under conditions of power, approach toward a social target was driven more by the target's usefulness, defined in terms of the perceiver's goals, than in low-power and baseline conditions. This instrumental response to power, which was linked to the presence of an active goal, was observed using multiple instantiations of power, different measures of approach, a variety of goals, and several types of instrumental and noninstrumental target attributes. Implications for research on the psychology of power, automatic goal pursuit, and self-objectification theory are discussed.

  19. Microwave and hot air drying of garlic puree: drying kinetics and quality characteristics

    NASA Astrophysics Data System (ADS)

    İlter, Işıl; Akyıl, Saniye; Devseren, Esra; Okut, Dilara; Koç, Mehmet; Kaymak Ertekin, Figen

    2018-02-01

    In this study, the effect of hot air and microwave drying on drying kinetics and some quality characteristics such as water activity, color, optic index and volatile oil of garlic puree was investigated. Optic index representing browning of the garlic puree increased excessively with an increase in microwave power and hot air drying temperature. However, volatile oil content of the dried samples was decreased by increasing of temperature and microwave power. By increasing drying temperature (50, 60 and 70 °C) and microwave power (180, 360 and 540 W), the drying time decreased from 8.5 h to 4 min. In order to determine the kinetic parameters, the experimental drying data were fitted to various semi-empirical models beside 2nd Fick's diffusion equation. Among them, the Page model gave a better fit for microwave-drying, while Logarithmic model gave a better fit for hot air drying. By increasing the microwave power and hot air drying temperature, the effective moisture diffusivity, De values ranged from 0.76×10-8 to 2.85×10-8 m2/s and from 2.21×10-10 to 3.07×10-10 m2/s, respectively. The activation energy was calculated as 20.90 kJ/mol for hot air drying and 21.96 W/g for microwave drying using an Arrhenius type equation.

  20. Application of Autonomous Smart Inverter Volt-VAR Function for Voltage Reduction Energy Savings and Power Quality in Electric Distribution Systems: Preprint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ding, Fei; Nagarajan, Adarsh; Baggu, Murali

    This paper evaluated the impact of smart inverter Volt-VAR function on voltage reduction energy saving and power quality in electric power distribution systems. A methodology to implement the voltage reduction optimization was developed by controlling the substation LTC and capacitor banks, and having smart inverters participate through their autonomous Volt-VAR control. In addition, a power quality scoring methodology was proposed and utilized to quantify the effect on power distribution system power quality. All of these methodologies were applied to a utility distribution system model to evaluate the voltage reduction energy saving and power quality under various PV penetrations and smartmore » inverter densities.« less

  1. Strength training for athletes: does it really help sports performance?

    PubMed

    McGuigan, Michael R; Wright, Glenn A; Fleck, Steven J

    2012-03-01

    The use of strength training designed to increase underlying strength and power qualities in elite athletes in an attempt to improve athletic performance is commonplace. Although the extent to which strength and power are important to sports performance may vary depending on the activity, the associations between these qualities and performance have been well documented in the literature. The purpose of this review is to provide a brief overview of strength training research to determine if it really helps improve athletic performance. While there is a need for more research with elite athletes to investigate the relationship between strength training and athletic performance, there is sufficient evidence for strength training programs to continue to be an integral part of athletic preparation in team sports.

  2. High repetition rate, high energy, actively Q-switched all-in-fiber laser

    NASA Astrophysics Data System (ADS)

    Lecourt, J. B.; Bertrand, A.; Guillemet, S.; Hernandez, Y.; Giannone, D.

    2010-05-01

    We report an actively Q-switched Ytterbium-doped all-in-fibre laser delivering 10ns pulses with high repetition rate (from 100kHz to 1MHz). The laser operation has been validated at three different wavelengths (1040, 1050 and 1064nm). The laser can deliver up to 20Watts average power with an high beam quality (M2 = 1).

  3. Portuguese Honeys from Different Geographical and Botanical Origins: A 4-Year Stability Study Regarding Quality Parameters and Antioxidant Activity.

    PubMed

    Soares, Sonia; Pinto, Diana; Rodrigues, Francisca; Alves, Rita C; Oliveira, M Beatriz P P

    2017-08-11

    Portuguese honeys (n = 15) from different botanical and geographical origins were analysed regarding their quality parameters (diastase activity, hydroxymethylfurfural content, moisture and pH), colour (L*, a*, b*) and antioxidant profile (total phenolics content, total flavonoids content, DPPH• scavenging activity, and ferric reducing power). The samples were analysed fresh and after 4-years of storage (at 25 °C and protected from light). The hydroxymethylfurfural content and diastase activity of the fresh samples were in accordance with the recommended values described in the legislation. In general, the antioxidant activity of the samples correlated more with the bioactive compounds content than with colour. The storage affected differently each individual sample, especially regarding the antioxidant profile. Nevertheless, although in general the lightness of the samples decreased (and the redness increased), after 4 years, 11 samples still presented acceptable diastase activity and hydroxymethylfurfural values.

  4. Power Extension Package (PEP) system definition extension, orbital service module systems analysis study. Volume 10: PEP project plan

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Contents: project plan summary; project and mission objectives; related studies and technology support activities; technical summary; management; procurement approach; project definition items and schedule; resources; management review; controlled items; and safety, reliability, and quality assurance.

  5. PQScal (Power Quality Score Calculation for Distribution Systems with DER Integration)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Power Quality is of great importance to evaluate the “health” of a distribution system, especially when the distributed energy resource (DER) penetration becomes more significant. The individual components that make up power quality, such as voltage magnitude and unbalance, can be measured in simulations or in the field, however, a comprehensive method to incorporate all of these values into a single score doesn't exist. As a result, we propose a methodology to quantify the power quality health using the single number value, named as Power Quality Score (PQS). The PQS is dependent on six metrics that are developed based onmore » both components that directly impact power quality and those are often reference in the context of power quality. These six metrics are named as System Average Voltage Magnitude Violation Index (SAVMVI), System Average Voltage Fluctuation Index (SAVFI), System Average Voltage Unbalance Index (SAVUI), System Control Device Operation Index (SCDOI), System Reactive Power Demand Index (SRPDI) and System Energy Loss Index (SELI). This software tool, PQScal, is developed based on this novel PQS methodology. Besides of traditional distribution systems, PQScal can also measure the power quality for distribution systems with various DER penetrations. PQScal has been tested on two utility distribution feeders with distinct model characteristics and its effectiveness has been proved. In sum, PQScal can help utilities or other parties to measure the power quality of distribution systems with DER integration easily and effectively.« less

  6. Creation of Power Reserves Under the Market Economy Conditions

    NASA Astrophysics Data System (ADS)

    Mahnitko, A.; Gerhards, J.; Lomane, T.; Ribakov, S.

    2008-09-01

    The main task of the control over an electric power system (EPS) is to ensure reliable power supply at the least cost. In this case, requirements to the electric power quality, power supply reliability and cost limitations on the energy resources must be observed. The available power reserve in an EPS is the necessary condition to keep it in operation with maintenance of normal operating variables (frequency, node voltage, power flows via the transmission lines, etc.). The authors examine possibilities to create power reserves that could be offered for sale by the electric power producer. They consider a procedure of price formation for the power reserves and propose a relevant mathematical model for a united EPS, the initial data being the fuel-cost functions for individual systems, technological limitations on the active power generation and consumers' load. As the criterion of optimization the maximum profit for the producer is taken. The model is exemplified by a concentrated EPS. The computations have been performed using the MATLAB program.

  7. Effects of a Meditation Program on Nurses' Power and Quality of Life.

    PubMed

    Chang, Sun Ju; Kwak, Eun Young; Hahm, Bong-Jin; Seo, Se Hee; Lee, Da Woon; Jang, Sun Joo

    2016-07-01

    This study evaluated the effects of meditation programs on nurses' power and quality of life. In this study, Barrett's power theory derived from Rogers' unitary human being science was used as a theoretical framework. A randomized controlled design with 50 recruited and randomly allocated participants was used. The results demonstrated that the eight-week meditation program significantly improved nurses' power and quality of life. These results suggest that meditation has positive effects on power and quality of life. © The Author(s) 2016.

  8. Using particle swarm optimization to enhance PI controller performances for active and reactive power control in wind energy conversion systems

    NASA Astrophysics Data System (ADS)

    Taleb, M.; Cherkaoui, M.; Hbib, M.

    2018-05-01

    Recently, renewable energy sources are impacting seriously power quality of the grids in term of frequency and voltage stability, due to their intermittence and less forecasting accuracy. Among these sources, wind energy conversion systems (WECS) received a great interest and especially the configuration with Doubly Fed Induction Generator. However, WECS strongly nonlinear, are making their control not easy by classical approaches such as a PI. In this paper, we continue deepen study of PI controller used in active and reactive power control of this kind of WECS. Particle Swarm Optimization (PSO) is suggested to improve its dynamic performances and its robustness against parameters variations. This work highlights the performances of PSO optimized PI control against classical PI tuned with poles compensation strategy. Simulations are carried out on MATLAB-SIMULINK software.

  9. BANNOCK CREEK, POWER COUNTY, IDAHO - WATER QUALITY STATUS REPORT, 1980 - 1981

    EPA Science Inventory

    Bannock Creek, Idaho (17040206) is a small agricultural watershed. The basin is partially on the Fort Hall Reservation. Several large farms and leases of reservation land are active in the watershed. Bannock Creek and its tributaries were sampled for suspended sediment load an...

  10. Research on Holographic Evaluation of Service Quality in Power Data Network

    NASA Astrophysics Data System (ADS)

    Wei, Chen; Jing, Tao; Ji, Yutong

    2018-01-01

    With the rapid development of power data network, the continuous development of the Power data application service system, more and more service systems are being put into operation. Following this, the higher requirements for network quality and service quality are raised, in the actual process for the network operation and maintenance. This paper describes the electricity network and data network services status. A holographic assessment model was presented to achieve a comprehensive intelligence assessment on the power data network and quality of service in the operation and maintenance on the power data network. This evaluation method avoids the problems caused by traditional means which performs a single assessment of network performance quality. This intelligent Evaluation method can improve the efficiency of network operation and maintenance guarantee the quality of real-time service in the power data network..

  11. Evaluation of thermal effects on the beam quality of disk laser with unstable resonator

    NASA Astrophysics Data System (ADS)

    Shayganmanesh, Mahdi; Beirami, Reza

    2017-01-01

    In this paper thermal effects of the disk active medium and associated effects on the beam quality of laser are investigated. Using Collins integral and iterative method, transverse mode of an unstable resonator including a Yb:YAG active medium in disk geometry is calculated. After that the beam quality of the laser is calculated based on the generalized beam characterization method. Thermal lensing of the disk is calculated based on the OPD (Optical Path Difference) concept. Five factors influencing the OPD including temperature gradient, disk thermal expansion, photo-elastic effect, electronic lens and disk deformation are considered in our calculations. The calculations show that the effect of disk deformation factor on the quality of laser beam in the resonator is strong. However the total effect of all the thermal factors on the internal beam quality is fewer. Also it is shown that thermal effects degrade the output power, beam profile and beam quality of the output laser beam severely. As well the magnitude of each of affecting factors is evaluated distinctly.

  12. College-Bound Communities. Lumina Foundation Focus™. Summer 2014

    ERIC Educational Resources Information Center

    Giegerich, Steve

    2014-01-01

    Research shows a direct correlation between thriving cities and high levels of college-level learning. Regions with robust levels of educational attainment have stronger economies, greater individual earning power, and better quality of life. The Lumina Foundation is actively supporting large-scale efforts in 55 metro regions--to help adults…

  13. Increasing Physical Activity in Nursing Home Residents Using Student Power, Not Dollars

    ERIC Educational Resources Information Center

    Romack, Jennifer L.

    2004-01-01

    Nursing home programs committed to providing quality care need to investigate innovative ways to meet today's budget challenges. The purpose of this article is to describe a creative collaboration between a nonprofit nursing home facility and a suburban university. Through service-learning, undergraduate students planned and implemented…

  14. PI and fuzzy logic controllers for shunt Active Power Filter--a report.

    PubMed

    P, Karuppanan; Mahapatra, Kamala Kanta

    2012-01-01

    This paper presents a shunt Active Power Filter (APF) for power quality improvements in terms of harmonics and reactive power compensation in the distribution network. The compensation process is based only on source current extraction that reduces the number of sensors as well as its complexity. A Proportional Integral (PI) or Fuzzy Logic Controller (FLC) is used to extract the required reference current from the distorted line-current, and this controls the DC-side capacitor voltage of the inverter. The shunt APF is implemented with PWM-current controlled Voltage Source Inverter (VSI) and the switching patterns are generated through a novel Adaptive-Fuzzy Hysteresis Current Controller (A-F-HCC). The proposed adaptive-fuzzy-HCC is compared with fixed-HCC and adaptive-HCC techniques and the superior features of this novel approach are established. The FLC based shunt APF system is validated through extensive simulation for diode-rectifier/R-L loads. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Power transformation for enhancing responsiveness of quality of life questionnaire.

    PubMed

    Zhou, YanYan Ange

    2015-01-01

    We investigate the effect of power transformation of raw scores on the responsiveness of quality of life survey. The procedure maximizes the paired t-test value on the power transformed data to obtain an optimal power range. The parallel between the Box-Cox transformation is also investigated for the quality of life data.

  16. Multi-kW coherent combining of fiber lasers seeded with pseudo random phase modulated light

    NASA Astrophysics Data System (ADS)

    Flores, Angel; Ehrehreich, Thomas; Holten, Roger; Anderson, Brian; Dajani, Iyad

    2016-03-01

    We report efficient coherent beam combining of five kilowatt-class fiber amplifiers with a diffractive optical element (DOE). Based on a master oscillator power amplifier (MOPA) configuration, the amplifiers were seeded with pseudo random phase modulated light. Each non-polarization maintaining fiber amplifier was optically path length matched and provides approximately 1.2 kW of near diffraction-limited output power (measured M2<1.1). Consequently, a low power sample of each laser was utilized for active linear polarization control. A low power sample of the combined beam after the DOE provided an error signal for active phase locking which was performed via Locking of Optical Coherence by Single-Detector Electronic-Frequency Tagging (LOCSET). After phase stabilization, the beams were coherently combined via the 1x5 DOE. A total combined output power of 4.9 kW was achieved with 82% combining efficiency and excellent beam quality (M2<1.1). The intrinsic DOE splitter loss was 5%. Similarly, losses due in part to non-ideal polarization, ASE content, uncorrelated wavefront errors, and misalignment errors contributed to the efficiency reduction.

  17. Feasibility of eyes open alpha power training for mental enhancement in elite gymnasts.

    PubMed

    Dekker, Marian K J; van den Berg, Berber R; Denissen, Ad J M; Sitskoorn, Margriet M; van Boxtel, Geert J M

    2014-01-01

    This study focuses on a novel, easy to use and instruction-less method for mental training in athletes. Previous findings suggest that particular mental capacities are needed for achieving peak performance; including attentional control, focus, relaxation and positive affect. Electroencephalography (EEG) alpha brain activity has been associated with neural inhibition during processes of selective attention, for improving efficiency in information processing. Here we hypothesised that eyes open alpha power training by music teaches athletes to (1) learn to self-regulate their brain activity, and (2) learn to increase their baseline alpha power, herewith improving mental capacities such as focusing the allocation of attention. The study was double-blind and placebo-controlled. Twelve elite gymnasts were either given eyes open alpha power training or random beta power training (controls). Results indicate small improvements in sleep quality, mental and physical shape. In our first attempt at getting a grip on mental capacities in athletes, we think this novel training method can be promising. Because gymnastics is one of the most mentally demanding sports, we value even small benefits for the athlete and consider them indicative for future research.

  18. Phenolic Content, Antioxidant Capacity and Quality of Chokeberry (Aronia melanocarpa) Products.

    PubMed

    Tolić, Mandica-Tamara; Jurčević, Irena Landeka; Krbavčić, Ines Panjkota; Marković, Ksenija; Vahčić, Nada

    2015-06-01

    Chokeberries ( Aronia melanocarpa ) are rarely used in diet in Croatia but they have high content of polyphenolic compounds and one of the highest in vitro antioxidant activities among fruits. The aim of this study is to compare the quality, phenolic content and antioxidant capacity of different chokeberry products (juices, powders, fruit tea, capsules and dried berries). It can be expected that processing influences antioxidant activity and phenolic content of final products reaching consumers. Characterisation of phenolic compounds was carried out by using spectroscopic methods (Folin-Ciocalteu and pH differential methods). Antioxidant activity of chokeberry products was determined using 2,2-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. The results show that the investigated products contain high amount of phenols (3002 to 6639 mg per L and 1494 to 5292 mg per 100 g of dry matter) and lower amount of total anthocyanins (150 to 1228 mg per L and 141 to 2468 mg per 100 g of dry matter). The examined juices and other chokeberry products possess high antioxidant capacity (12.09 to 40.19 mmol per L or 58.49 to 191.31 mmol per 100 g of dry matter, respectively) and reducing power (38.71 to 79.86 mmol per L or 13.50 to 68.60 mmol per 100 g of dry matter, respectively). On the basis of phenolic content and antioxidant activity, capsules and powders stand out among other products. The study indicates that there are significant differences (p<0.05) in the quality, phenolic content and antioxidant capacity among examined products.

  19. Phenolic Content, Antioxidant Capacity and Quality of Chokeberry (Aronia melanocarpa) Products

    PubMed Central

    Jurčević, Irena Landeka; Krbavčić, Ines Panjkota; Marković, Ksenija; Vahčić, Nada

    2015-01-01

    Summary Chokeberries (Aronia melanocarpa) are rarely used in diet in Croatia but they have high content of polyphenolic compounds and one of the highest in vitro antioxidant activities among fruits. The aim of this study is to compare the quality, phenolic content and antioxidant capacity of different chokeberry products (juices, powders, fruit tea, capsules and dried berries). It can be expected that processing influences antioxidant activity and phenolic content of final products reaching consumers. Characterisation of phenolic compounds was carried out by using spectroscopic methods (Folin–Ciocalteu and pH differential methods). Antioxidant activity of chokeberry products was determined using 2,2-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. The results show that the investigated products contain high amount of phenols (3002 to 6639 mg per L and 1494 to 5292 mg per 100 g of dry matter) and lower amount of total anthocyanins (150 to 1228 mg per L and 141 to 2468 mg per 100 g of dry matter). The examined juices and other chokeberry products possess high antioxidant capacity (12.09 to 40.19 mmol per L or 58.49 to 191.31 mmol per 100 g of dry matter, respectively) and reducing power (38.71 to 79.86 mmol per L or 13.50 to 68.60 mmol per 100 g of dry matter, respectively). On the basis of phenolic content and antioxidant activity, capsules and powders stand out among other products. The study indicates that there are significant differences (p<0.05) in the quality, phenolic content and antioxidant capacity among examined products. PMID:27904346

  20. Recent developments in CO2 lasers

    NASA Astrophysics Data System (ADS)

    Du, Keming

    1993-05-01

    CO2 lasers have been used in industry mainly for such things as cutting, welding, and surface processing. To conduct a broad spectrum of high-speed and high-quality applications, most of the developments in industrial CO2 lasers at the ILT are aimed at increasing the output power, optimizing the beam quality, and reducing the production costs. Most of the commercial CO2 lasers above 5 kW are transverse-flow systems using dc excitation. The applications of these lasers are limited due to the lower beam quality, the poor point stability, and the lower modulation frequency. To overcome the problems we developed a fast axial- flow CO2 laser using rf excitation with an output of 13 kW. In section 2 some of the results are discussed concerning the gas flow, the discharge, the resonator design, optical effects of active medium, the aerodynamic window, and the modulation of the output power. The first CO2 lasers ever built are diffusion-cooled systems with conventional dc excited cylindrical discharge tubes surrounded by cooling jackets. The output power per unit length is limited to 50 W/m by those lasers with cylindrical tubes. In the past few years considerable increases in the output power were achieved, using new mechanical geometries, excitation- techniques, and resonator designs. This progress in diffusion-cooled CO2 lasers is presented in section 3.

  1. Dual Q-switched laser outputs from a single lasing medium using an intracavity MEMS micromirror array.

    PubMed

    Bauer, Ralf; Lubeigt, Walter; Uttamchandani, Deepak

    2012-09-01

    An intracavity array of individually controlled microelectromechanical system scanning micromirrors was used to actively Q-switch a single side-pumped Nd:YAG gain medium. Two equal power independent laser outputs were simultaneously obtained by separate actuation of two adjacent micromirrors with a combined average output power of 125 mW. Pulse durations of 28 ns FWHM at 8.7 kHz repetition frequency and 34 ns FWHM at 7.9 kHz repetition frequency were observed for the two output beams with beam quality factors M2 of 1.2 and 1.1 and peak powers of 253 W and 232 W, respectively.

  2. CMOS Amperometric ADC With High Sensitivity, Dynamic Range and Power Efficiency for Air Quality Monitoring.

    PubMed

    Li, Haitao; Boling, C Sam; Mason, Andrew J

    2016-08-01

    Airborne pollutants are a leading cause of illness and mortality globally. Electrochemical gas sensors show great promise for personal air quality monitoring to address this worldwide health crisis. However, implementing miniaturized arrays of such sensors demands high performance instrumentation circuits that simultaneously meet challenging power, area, sensitivity, noise and dynamic range goals. This paper presents a new multi-channel CMOS amperometric ADC featuring pixel-level architecture for gas sensor arrays. The circuit combines digital modulation of input currents and an incremental Σ∆ ADC to achieve wide dynamic range and high sensitivity with very high power efficiency and compact size. Fabricated in 0.5 [Formula: see text] CMOS, the circuit was measured to have 164 dB cross-scale dynamic range, 100 fA sensitivity while consuming only 241 [Formula: see text] and 0.157 [Formula: see text] active area per channel. Electrochemical experiments with liquid and gas targets demonstrate the circuit's real-time response to a wide range of analyte concentrations.

  3. Marine ecological habitat: a case study on projected thermal power plant around Dharamtar Creek, India.

    PubMed

    Kulkarni, Vikrant A; Naidu, Velamala S; Jagtap, Tanaji G

    2011-03-01

    Estuaries and tidal creeks, harboring mangroves particularly, face tremendous anthropogenic pressures. Expansion of mega cities and the thermal power plants are generally proposed in the vicinity of estuaries and creek, due to the feasibility of intake and discharge of water for cooling. Discharges from such developments remain constant threat of increasing thermal pollution and affecting the quality of environment. The baseline information on prevailing quality of aquatic environment comes handy for understanding alterations due to such activities. Principle component analysis (PCA) revealed that temperature, pH, salinity, suspended solids, DO, BOD and phaeophytins are major parameters influencing the creek system. Heated effluents may have direct and adverse impacts on these parameters, altering biotic constituents. Hence, periodic and detailed observations are necessary to estimate exact response of biotic communities to changing environment. The present paper is based on case study, projecting a power plant in the vicinity of major mangrove habitats of Dharamtar creek.

  4. Artificial enzyme-powered microfish for water-quality testing.

    PubMed

    Orozco, Jahir; García-Gradilla, Victor; D'Agostino, Mattia; Gao, Wei; Cortés, Allan; Wang, Joseph

    2013-01-22

    We present a novel micromotor-based strategy for water-quality testing based on changes in the propulsion behavior of artificial biocatalytic microswimmers in the presence of aquatic pollutants. The new micromotor toxicity testing concept mimics live-fish water testing and relies on the toxin-induced inhibition of the enzyme catalase, responsible for the biocatalytic bubble propulsion of tubular microengines. The locomotion and survival of the artificial microfish are thus impaired by exposure to a broad range of contaminants, that lead to distinct time-dependent irreversible losses in the catalase activity, and hence of the propulsion behavior. Such use of enzyme-powered biocompatible polymeric (PEDOT)/Au-catalase tubular microengine offers highly sensitive direct optical visualization of changes in the swimming behavior in the presence of common contaminants and hence to a direct real-time assessment of the water quality. Quantitative data on the adverse effects of the various toxins upon the swimming behavior of the enzyme-powered artificial swimmer are obtained by estimating common ecotoxicological parameters, including the EC(50) (exposure concentration causing 50% attenuation of the microfish locomotion) and the swimmer survival time (lifetime expectancy). Such novel use of artificial microfish addresses major standardization and reproducibility problems as well as ethical concerns associated with live-fish toxicity assays and hence offers an attractive alternative to the common use of aquatic organisms for water-quality testing.

  5. Power Profiles and In Vitro Optical Quality of Scleral Contact Lenses: Effect of the Aperture and Power.

    PubMed

    Domínguez-Vicent, Alberto; Esteve-Taboada, Jose Juan; Recchioni, Alberto; Brautaset, Rune

    2018-05-01

    To assess the power profile and in vitro optical quality of scleral contact lenses with different powers as a function of the optical aperture. The mini and semiscleral contact lenses (Procornea) were measured for five powers per design. The NIMO TR-1504 (Lambda-X) was used to assess the power profile and Zernike coefficients of each contact lens. Ten measurements per lens were taken at 3- and 6-mm apertures. Furthermore, the optical quality of each lens was described in Zernike coefficients, modulation transfer function, and point spread function (PSF). A convolution of each lens PSF with an eye-chart image was also computed. The optical power fluctuated less than 0.5 diopters (D) along the optical zone of each lens. However, the optical power obtained for some lenses did not match with its corresponding nominal one, the maximum difference being 0.5 D. In optical quality, small differences were obtained among all lenses within the same design. Although significant differences were obtained among lenses (P<0.05), these showed small impact in the image quality of each convolution. Insignificant power fluctuations were obtained along the optical zone measured for each scleral lens. Additionally, the optical quality of both lenses has showed to be independent of the lens power within the same aperture.

  6. A Smart Power Electronic Multiconverter for the Residential Sector.

    PubMed

    Guerrero-Martinez, Miguel Angel; Milanes-Montero, Maria Isabel; Barrero-Gonzalez, Fermin; Miñambres-Marcos, Victor Manuel; Romero-Cadaval, Enrique; Gonzalez-Romera, Eva

    2017-05-26

    The future of the grid includes distributed generation and smart grid technologies. Demand Side Management (DSM) systems will also be essential to achieve a high level of reliability and robustness in power systems. To do that, expanding the Advanced Metering Infrastructure (AMI) and Energy Management Systems (EMS) are necessary. The trend direction is towards the creation of energy resource hubs, such as the smart community concept. This paper presents a smart multiconverter system for residential/housing sector with a Hybrid Energy Storage System (HESS) consisting of supercapacitor and battery, and with local photovoltaic (PV) energy source integration. The device works as a distributed energy unit located in each house of the community, receiving active power set-points provided by a smart community EMS. This central EMS is responsible for managing the active energy flows between the electricity grid, renewable energy sources, storage equipment and loads existing in the community. The proposed multiconverter is responsible for complying with the reference active power set-points with proper power quality; guaranteeing that the local PV modules operate with a Maximum Power Point Tracking (MPPT) algorithm; and extending the lifetime of the battery thanks to a cooperative operation of the HESS. A simulation model has been developed in order to show the detailed operation of the system. Finally, a prototype of the multiconverter platform has been implemented and some experimental tests have been carried out to validate it.

  7. A Smart Power Electronic Multiconverter for the Residential Sector

    PubMed Central

    Guerrero-Martinez, Miguel Angel; Milanes-Montero, Maria Isabel; Barrero-Gonzalez, Fermin; Miñambres-Marcos, Victor Manuel; Romero-Cadaval, Enrique; Gonzalez-Romera, Eva

    2017-01-01

    The future of the grid includes distributed generation and smart grid technologies. Demand Side Management (DSM) systems will also be essential to achieve a high level of reliability and robustness in power systems. To do that, expanding the Advanced Metering Infrastructure (AMI) and Energy Management Systems (EMS) are necessary. The trend direction is towards the creation of energy resource hubs, such as the smart community concept. This paper presents a smart multiconverter system for residential/housing sector with a Hybrid Energy Storage System (HESS) consisting of supercapacitor and battery, and with local photovoltaic (PV) energy source integration. The device works as a distributed energy unit located in each house of the community, receiving active power set-points provided by a smart community EMS. This central EMS is responsible for managing the active energy flows between the electricity grid, renewable energy sources, storage equipment and loads existing in the community. The proposed multiconverter is responsible for complying with the reference active power set-points with proper power quality; guaranteeing that the local PV modules operate with a Maximum Power Point Tracking (MPPT) algorithm; and extending the lifetime of the battery thanks to a cooperative operation of the HESS. A simulation model has been developed in order to show the detailed operation of the system. Finally, a prototype of the multiconverter platform has been implemented and some experimental tests have been carried out to validate it. PMID:28587131

  8. Framework for power and activity factor allocation in a multiclass CDMA system

    NASA Astrophysics Data System (ADS)

    Wu, Xinzhou; Srikant, Rayadurgam

    2001-07-01

    We consider a multimedia CDMA uplink where there are multiple classes of users with different Quality-of-Service (QoS) requirements. Each user is modeled as an ON-OFF source, where in the ON state, the user transmits a fixed number of bits in each time slot and in the OFF state, the user is silent. The probability of being in the ON state, known as the activity factor, could be different for different users. Assuming a constant channel gain, we first characterize the set of transmit power levels, activity factors and number of users in each class that can be supported by a system with a given spreading gain under the constraint that each user's QoS requirement must be met. Using this characterization, we then present a utility function-based algorithm for choosing the activity factors of elastic users in the network.

  9. Propagation of nuclear data uncertainties for fusion power measurements

    NASA Astrophysics Data System (ADS)

    Sjöstrand, Henrik; Conroy, Sean; Helgesson, Petter; Hernandez, Solis Augusto; Koning, Arjan; Pomp, Stephan; Rochman, Dimitri

    2017-09-01

    Neutron measurements using neutron activation systems are an essential part of the diagnostic system at large fusion machines such as JET and ITER. Nuclear data is used to infer the neutron yield. Consequently, high-quality nuclear data is essential for the proper determination of the neutron yield and fusion power. However, uncertainties due to nuclear data are not fully taken into account in uncertainty analysis for neutron yield calibrations using activation foils. This paper investigates the neutron yield uncertainty due to nuclear data using the so-called Total Monte Carlo Method. The work is performed using a detailed MCNP model of the JET fusion machine; the uncertainties due to the cross-sections and angular distributions in JET structural materials, as well as the activation cross-sections in the activation foils, are analysed. It is found that a significant contribution to the neutron yield uncertainty can come from uncertainties in the nuclear data.

  10. An efficient transmission power control scheme for temperature variation in wireless sensor networks.

    PubMed

    Lee, Jungwook; Chung, Kwangsue

    2011-01-01

    Wireless sensor networks collect data from several nodes dispersed at remote sites. Sensor nodes can be installed in harsh environments such as deserts, cities, and indoors, where the link quality changes considerably over time. Particularly, changes in transmission power may be caused by temperature, humidity, and other factors. In order to compensate for link quality changes, existing schemes detect the link quality changes between nodes and control transmission power through a series of feedback processes, but these approaches can cause heavy overhead with the additional control packets needed. In this paper, the change of the link quality according to temperature is examined through empirical experimentation. A new power control scheme combining both temperature-aware link quality compensation and a closed-loop feedback process to adapt to link quality changes is proposed. We prove that the proposed scheme effectively adapts the transmission power to the changing link quality with less control overhead and energy consumption.

  11. What affects the subjective sleep quality of hospitalized elderly patients?

    PubMed

    Park, Mi Jeong; Kim, Kon Hee

    2017-03-01

    The present study aimed to identify the factors affecting the subjective sleep quality in elderly inpatients. The participants were 290 older adults admitted in three general hospitals. Data were collected using a structured questionnaire consisting of scales for general characteristics, sleep quality, activities of daily living, instrumental activities of daily living and depression. Collected data were analyzed by descriptive statistics, t-test, one-way anova, Scheffé post-hoc, Pearson's correlation coefficient and stepwise multiple regression. There were statistically significant differences in sleep quality according to age, education level, marital status, monthly income and number of cohabitants. The most powerful predictor of sleep quality was depression (P < 0.01, R 2  = 0.30). Five variables, depression, perceived health status, diagnosis, number of cohabitants and duration of hospitalization; explained 43.0% of the total variance in sleep quality. Elderly inpatients suffered from low sleep quality, and depression affected their sleep. We should develop and apply hospital-tailored sleep interventions considering older adults' depression, and then hospitalized older adults' sleep could improve. Furthermore, it is useful to identify other sleep-related factors. Geriatr Gerontol Int 2017; 17: 471-479. © 2016 Japan Geriatrics Society.

  12. Gender, marital power, and marital quality in later life.

    PubMed

    Bulanda, Jennifer Roebuck

    2011-01-01

    This study uses data from the 1992 Health and Retirement Study to examine gender differences in marital power and marital quality among older adults and to assess whether there are gender differences in the correlates of marital quality and marital power in later life. Results show that women report lower marital happiness, marital interaction, and marital power than do men, on average. These differences persist even after controlling for a number of life-course events and transitions. Further, results show that gender differences are also evident in the relationship of employment, childrearing, caregiving, and health factors with marital quality and power.

  13. High-brightness 1.3 μm InAs/GaAs quantum dot tapered laser with high temperature stability.

    PubMed

    Cao, Yulian; Ji, Haiming; Xu, Pengfei; Gu, Yongxian; Ma, Wenquan; Yang, Tao

    2012-10-01

    We demonstrate high-brightness 1.3 μm tapered lasers with high temperature stability by using p-doped InAs/GaAs quantum dots (QDs) as the active region. It is found that the beam quality factor M(2) for the devices is almost unchanged as the light power and temperature increase. The almost constant M(2) results from the p-doped QD active region.

  14. Consumer input into health care: Time for a new active and comprehensive model of consumer involvement.

    PubMed

    Hall, Alix E; Bryant, Jamie; Sanson-Fisher, Rob W; Fradgley, Elizabeth A; Proietto, Anthony M; Roos, Ian

    2018-03-07

    To ensure the provision of patient-centred health care, it is essential that consumers are actively involved in the process of determining and implementing health-care quality improvements. However, common strategies used to involve consumers in quality improvements, such as consumer membership on committees and collection of patient feedback via surveys, are ineffective and have a number of limitations, including: limited representativeness; tokenism; a lack of reliable and valid patient feedback data; infrequent assessment of patient feedback; delays in acquiring feedback; and how collected feedback is used to drive health-care improvements. We propose a new active model of consumer engagement that aims to overcome these limitations. This model involves the following: (i) the development of a new measure of consumer perceptions; (ii) low cost and frequent electronic data collection of patient views of quality improvements; (iii) efficient feedback to the health-care decision makers; and (iv) active involvement of consumers that fosters power to influence health system changes. © 2018 The Authors Health Expectations published by John Wiley & Sons Ltd.

  15. Participation of National Medical Associations in quality improvement activities - International comparison and the Israeli case

    PubMed Central

    2014-01-01

    Background Many countries have devoted considerable efforts in an attempt to improve the performance of their health care systems. National Medical Associations (NMAs), along with other stakeholders, play a part in the promotion of such activities. The purpose of this paper is to explore the nature and level of participation of NMAs in activities of quality improvement in medicine, with a specific emphasis on Israel. Methods The authors conducted a survey among NMAs around the world inquiring as to their involvement in three central aspects of quality improvement: clinical guidelines, quality measurement and continuing medical education (CME). In addition, they conducted a review of the literature in order to gather more information and complete the data collected in the survey. The findings were processed and analyzed comparatively. Results Most of the NMAs surveyed participate in quality improvement activities at least to some extent. NMAs' main involvement is in the regulation of CME and they are involved to a much lesser extent in the preparation of clinical guidelines and in quality measurement. In Israel, the Israeli Medical Association (IMA) has a dominant role in both the preparation of clinical guidelines and the regulation of CME credits. Discussion It is possible that the expertise maintained by the profession, coupled with the organizational power of the NMA as a union, is viewed as beneficial for regulating educational activities in medicine such as CME. Conversely, the issuing of clinical guidelines is usually regarded as a typical scientific activity, and therefore often rests in the hands of professional medical societies. Quality measurement is regarded as a distinctive administrative tool and is usually found in the province of governments. Based on the typology that we introduced in our previous paper, we discovered that the extent of NMAs’ involvement in quality improvement coincides with the mode of governance of the health care system. Conclusions The nature and level of participation of NMAs in activities of quality improvement varies widely. Collaboration of NMAs in this field with other stakeholders is not uncommon, and may contribute to the further development of quality improvement in medicine. PMID:24808940

  16. Autonomic nervous system balance in children and adolescents with craniopharyngioma and hypothalamic obesity.

    PubMed

    Cohen, Michal; Syme, Catriona; McCrindle, Brian W; Hamilton, Jill

    2013-06-01

    Dysregulation of the autonomic nervous system is thought to be involved in craniopharyngioma-related hypothalamic obesity (CRHO). Increased parasympathetic activity and decreased sympathetic activity have been suggested. We aimed to study autonomic activity using heart rate variability (HRV) and biochemical measures in youth with CRHO compared with controls and to explore relationships between obesity and autonomic indices. A cross-sectional study of 16 youth with CRHO and 16 controls matched for sex, age, and BMI. Anthropometrics, fasting blood-work, resting energy expenditure (REE), 24-h HRV, and 24-h urine catecholamines were assessed. Quality of life, sleepiness, and autonomic symptoms were evaluated. Power spectral analysis of the HRV was performed. HRV power spectral analysis parameters of both parasympathetic activity (mean high frequency (HF (ms(2))) 611±504 vs 459±336, P=0.325) and sympathetic activity (median low frequency/HF 1.62 (1.37, 2.41) vs 1.89 (1.44, 2.99), P=0.650) did not differ between the groups. Parasympathetic activity negatively correlated with central adiposity in both groups (r=-0.53, P=0.034 and r=-0.54, P=0.029) and sympathetic activity positively correlated with central adiposity in CRHO (r=0.51, P=0.043). Youth with CRHO had significantly lower REE; lower health and activity scores in the quality of life questionnaires, and higher sleepiness scores. Autonomic activity was similar in CRHO and control subjects. The degree of central adiposity correlated negatively with parasympathetic activity and positively with sympathetic activity in children with CRHO. These results provide a new perspective regarding autonomic balance in this unique patient population.

  17. A design of wireless sensor networks for a power quality monitoring system.

    PubMed

    Lim, Yujin; Kim, Hak-Man; Kang, Sanggil

    2010-01-01

    Power grids deal with the business of generation, transmission, and distribution of electric power. Recently, interest in power quality in electrical distribution systems has increased rapidly. In Korea, the communication network to deliver voltage, current, and temperature measurements gathered from pole transformers to remote monitoring centers employs cellular mobile technology. Due to high cost of the cellular mobile technology, power quality monitoring measurements are limited and data gathering intervals are large. This causes difficulties in providing the power quality monitoring service. To alleviate the problems, in this paper we present a communication infrastructure to provide low cost, reliable data delivery. The communication infrastructure consists of wired connections between substations and monitoring centers, and wireless connections between pole transformers and substations. For the wireless connection, we employ a wireless sensor network and design its corresponding data forwarding protocol to improve the quality of data delivery. For the design, we adopt a tree-based data forwarding protocol in order to customize the distribution pattern of the power quality information. We verify the performance of the proposed data forwarding protocol quantitatively using the NS-2 network simulator.

  18. Power quality load management for large spacecraft electrical power systems

    NASA Technical Reports Server (NTRS)

    Lollar, Louis F.

    1988-01-01

    In December, 1986, a Center Director's Discretionary Fund (CDDF) proposal was granted to study power system control techniques in large space electrical power systems. Presented are the accomplishments in the area of power system control by power quality load management. In addition, information concerning the distortion problems in a 20 kHz ac power system is presented.

  19. High Efficiency, Transparent, Reusable, and Active PM2.5 Filters by Hierarchical Ag Nanowire Percolation Network.

    PubMed

    Jeong, Seongmin; Cho, Hyunmin; Han, Seonggeun; Won, Phillip; Lee, Habeom; Hong, Sukjoon; Yeo, Junyeob; Kwon, Jinhyeong; Ko, Seung Hwan

    2017-07-12

    Air quality has become a major public health issue in Asia including China, Korea, and India. Particulate matters are the major concern in air quality. We present the first environmental application demonstration of Ag nanowire percolation network for a novel, electrical type transparent, reusable, and active PM2.5 air filter although the Ag nanowire percolation network has been studied as a very promising transparent conductor in optoelectronics. Compared with previous particulate matter air filter study using relatively weaker short-range intermolecular force in polar polymeric nanofiber, Ag nanowire percolation network filters use stronger long-range electrostatic force to capture PM2.5, and they are highly efficient (>99.99%), transparent, working on an active mode, low power consumption, antibacterial, and reusable after simple washing. The proposed new particulate matter filter can be applied for a highly efficient, reusable, active and energy efficient filter for wearable electronics application.

  20. Powerful Learning with Public Purpose

    ERIC Educational Resources Information Center

    Cervone, Barbara

    2010-01-01

    Boredom and failure combine in a toxic brew that propels too many young people off the graduation path. Research shows that engaged students are more likely to perform well academically, that students who are challenged are less likely to be bored and disengaged, and that high-quality instruction and meaningful activities are key factors in…

  1. HIV, self-transcendence, and quality of life.

    PubMed

    Mellors, M P; Riley, T A; Erlen, J A

    1997-01-01

    Self-transcendence is a developmental characteristic that expands one's boundaries of the self to take on broader life perspectives, activities, and purposes that help one discover or make meaning of one's life. However, no quantitative studies were found in the research literature that focused on self-transcendence or on the relationship between self-transcendence and quality of life in people infected with HIV. To examine these variables in this population, 46 HIV-positive subjects completed Reed's Self-Transcendence Scale and Ferrans and Powers' Quality of Life Index. The results demonstrated that overall self-transcendence for this sample was relatively high; quality of life was higher than that reported in previous research; and there were some significant group differences among the three HIV clinical categories.

  2. Conjoint Analysis for New Service Development on Electricity Distribution in Indonesia

    NASA Astrophysics Data System (ADS)

    Widaningrum, D. L.; Chynthia; Astuti, L. D.; Seran, M. A. B.

    2017-07-01

    Many cases of illegal use of electricity in Indonesia is still rampant, especially for activities where the power source is not available, such as in the location of street vendors. It is not only detrimental to the state, but also harm the perpetrators of theft of electricity and the surrounding communities. The purpose of this study is to create New Service Development (NSD) to provide a new electricity source for street vendors' activity based on their preferences. The methods applied in NSD is Conjoint Analysis, Cluster Analysis, Quality Function Deployment (QFD), Service Blueprint, Process Flow Diagrams and Quality Control Plan. The results of this study are the attributes and their importance in the new electricity’s service based on street vendors’ preferences as customers, customer segmentation, service design for new service, designing technical response, designing operational procedures, the quality control plan of any existing operational procedures.

  3. Isolated Power Generation System Using Permanent Magnet Synchronous Generator with Improved Power Quality

    NASA Astrophysics Data System (ADS)

    Arya, Sabha Raj; Patel, Ashish; Giri, Ashutosh

    2018-06-01

    This paper deals wind energy based power generation system using Permanent Magnet Synchronous Generator (PMSG). It is controlled using advanced enhanced phase-lock loop for power quality features using distribution static compensator to eliminate the harmonics and to provide KVAR compensation as well as load balancing. It also manages rated potential at the point of common interface under linear and non-linear loads. In order to have better efficiency and reliable operation of PMSG driven by wind turbine, it is necessary to analyze the governing equation of wind based turbine and PMSG under fixed and variable wind speed. For handling power quality problems, power electronics based shunt connected custom power device is used in three wire system. The simulations in MATLAB/Simulink environment have been carried out in order to demonstrate this model and control approach used for the power quality enhancement. The performance results show the adequate performance of PMSG based power generation system and control algorithm.

  4. Isolated Power Generation System Using Permanent Magnet Synchronous Generator with Improved Power Quality

    NASA Astrophysics Data System (ADS)

    Arya, Sabha Raj; Patel, Ashish; Giri, Ashutosh

    2018-03-01

    This paper deals wind energy based power generation system using Permanent Magnet Synchronous Generator (PMSG). It is controlled using advanced enhanced phase-lock loop for power quality features using distribution static compensator to eliminate the harmonics and to provide KVAR compensation as well as load balancing. It also manages rated potential at the point of common interface under linear and non-linear loads. In order to have better efficiency and reliable operation of PMSG driven by wind turbine, it is necessary to analyze the governing equation of wind based turbine and PMSG under fixed and variable wind speed. For handling power quality problems, power electronics based shunt connected custom power device is used in three wire system. The simulations in MATLAB/Simulink environment have been carried out in order to demonstrate this model and control approach used for the power quality enhancement. The performance results show the adequate performance of PMSG based power generation system and control algorithm.

  5. Water Availability--The Connection Between Water Use and Quality

    USGS Publications Warehouse

    Hirsch, Robert M.; Hamilton, Pixie A.; Miller, Timothy L.; Myers, Donna N.

    2008-01-01

    Water availability has become a high priority in the United States, in large part because competition for water is becoming more intense across the Nation. Population growth in many areas competes with demands for water to support irrigation and power production. Cities, farms, and power plants compete for water needed by aquatic ecosystems to support their minimum flow requirements. At the same time, naturally occurring and human-related contaminants from chemical use, land use, and wastewater and industrial discharge are introduced into our waters and diminish its quality. The fact that degraded quality limits the availability and suitability of water for critical uses is a well-known reality in many communities. What may be less understood, but equally true, is that our everyday use of water can significantly affect water quality, and thus its availability. Landscape features (such as geology, soils, and vegetation) along with water-use practices (such as ground-water withdrawals and irrigation) govern water availability because, together, they affect the movement of chemical compounds over the land and in the subsurface. Understanding the interactions of human activities with natural sources and the landscape is critical to effectively managing water and sustaining water availability in the future.

  6. Carbon Monoxide Fumigation Improved the Quality, Nutrients, and Antioxidant Activities of Postharvest Peach

    PubMed Central

    Li, Ying; Pei, Fei

    2014-01-01

    Peaches (Prunus persica cv. Yanhong) were fumigated with carbon monoxide (CO) at 0, 0.5, 5, 10, and 20 μmol/L for 2 hours. The result showed that low concentration CO (0.5–10 μmol/L) might delay the decrease of firmness and titrable acid content, restrain the increase of decay incidence, and postpone the variation of soluble solids content, but treating peaches with high concentration CO (20 μmol/L) demonstrated adverse effects. Further research exhibited that exogenous CO could induce the phenylalnine ammonialyase activity, maintain nutrient contents such as Vitamin C, total flavonoid, and polyphenol, and enhance antioxidant activity according to reducing power and 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl radical scavenging activity. Treating peaches with appropriate concentration CO was beneficial to the quality, nutrients, and antioxidant activity of postharvest peaches during storage time. Therefore, CO fumigation might probably become a novel method to preserve postharvest peach and other fruits in the future. PMID:26904651

  7. Effects of ultrasonic pretreatments on quality, energy consumption and sterilization of barley grass in freeze drying.

    PubMed

    Cao, Xiaohuang; Zhang, Min; Mujumdar, Arun S; Zhong, Qifeng; Wang, Zhushang

    2018-01-01

    Barley grass is a plant resource for rehabilitation therapy. Its processing requires retaining nutrition well for rehabilitation cure of consumers. To meet the aim as well as low energy consumption and microbiological safety of products, ultrasonic treatments (UT) were applied to bathing materials at different power levels (10, 30, 45, 60W/L) for 10mins. After treatments, the bathed barley grass (100g) was freeze-dried under vacuum -0.09MPa with fixed power of 2W/g. Parameters of color, microbial colony, energy consumption, glass transition temperature, moisture content, water activity, taste substances, contents of flavonoid and chlorophyll were determined after drying. In contrast with no treatment case, UT (45W/L) decreased drying time by 14% and decreased energy consumption by 19%; UT (60W/L) decreased total microbial colonies by 33%. Also, UT (30W/L) yielded contents of flavonoid (9.2/kg) and chlorophyll (10.5g/kg) of dried sample; UT power (10W/L) yielded the highest L ∗ (51.5) and the lowest a ∗ (-9.3) value. Simultaneously, UT leads to a higher glass transition temperature (Tg), lower water activity and produces less sourness and bitterness of dried products. Ultra-sonication is an alternative to improve quality, flavor and energy consumption of barley grass in freeze drying. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Study on Power Ultrasound Optimization and Its Comparison with Conventional Thermal Processing for Treatment of Raw Honey

    PubMed Central

    2017-01-01

    Summary The present study was done to optimize the power ultrasound processing for maximizing diastase activity of and minimizing hydroxymethylfurfural (HMF) content in honey using response surface methodology. Experimental design with treatment time (1-15 min), amplitude (20-100%) and volume (40-80 mL) as independent variables under controlled temperature conditions was studied and it was concluded that treatment time of 8 min, amplitude of 60% and volume of 60 mL give optimal diastase activity and HMF content, i.e. 32.07 Schade units and 30.14 mg/kg, respectively. Further thermal profile analyses were done with initial heating temperatures of 65, 75, 85 and 95 ºC until temperature of honey reached up to 65 ºC followed by holding time of 25 min at 65 ºC, and the results were compared with thermal profile of honey treated with optimized power ultrasound. The quality characteristics like moisture, pH, diastase activity, HMF content, colour parameters and total colour difference were least affected by optimized power ultrasound treatment. Microbiological analysis also showed lower counts of aerobic mesophilic bacteria and in ultrasonically treated honey than in thermally processed honey samples complete destruction of coliforms, yeasts and moulds. Thus, it was concluded that power ultrasound under suggested operating conditions is an alternative nonthermal processing technique for honey. PMID:29540991

  9. 77 FR 26317 - Exemption of Material for Proposed Disposal Procedures for the Humboldt Bay Power Plant, Unit 3...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-03

    ... hazardous waste containing low-activity radioactive debris, at the US Ecology Idaho (USEI) Resource... for the disposal of waste from the HBPP at the US Ecology Idaho (USEI) facility in accordance with 10... significantly impact the quality of the human environment, and that the proposed action is the preferred...

  10. Environmental Quality Technology Demonstration, Evaluation and Transfer Activities

    DTIC Science & Technology

    1996-12-02

    and Appropriate Requirements) and ARAR support documentation for interim and final Installation Restoration Program (IRP) remedial actions . During the...Relevant and Appropriate Requirements (ARARs) for Fort Devens , Massachusetts. Delivered Federal Environmental Legislative Power Curve in hard copy and... Remedial Actions . Delivered revised tables for Desk Guide on Interpretation of Applicable or Relevant and Appropriate Requirements — Interim Draft

  11. Photovoltaic Impact Assessment of Smart Inverter Volt-VAR Control on Distribution System Conservation Voltage Reduction and Power Quality

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ding, Fei; Nagarajan, Adarsh; Chakraborty, Sudipta

    This report presents an impact assessment study of distributed photovoltaic (PV) with smart inverter Volt-VAR control on conservation voltage reduction (CVR) energy savings and distribution system power quality. CVR is a methodology of flattening and lowering a distribution system voltage profile in order to conserve energy. Traditional CVR relies on operating utility voltage regulators and switched capacitors. However, with the increased penetration of distributed PV systems, smart inverters provide the new opportunity to control local voltage and power factor by regulating the reactive power output, leading to a potential increase in CVR energy savings. This report proposes a methodology tomore » implement CVR scheme by operating voltage regulators, capacitors, and autonomous smart inverter Volt-VAR control in order to achieve increased CVR benefit. Power quality is an important consideration when operating a distribution system, especially when implementing CVR. It is easy to measure the individual components that make up power quality, but a comprehensive method to incorporate all of these values into a single score has yet to be undertaken. As a result, this report proposes a power quality scoring mechanism to measure the relative power quality of distribution systems using a single number, which is aptly named the 'power quality score' (PQS). Both the CVR and PQS methodologies were applied to two distribution system models, one obtained from the Hawaiian Electric Company (HECO) and another obtained from Pacific Gas and Electric (PG&E). These two models were converted to the OpenDSS platform using previous model conversion tools that were developed by NREL. Multiple scenarios including various PV penetration levels and smart inverter densities were simulated to analyze the impact of smart inverter Volt-VAR support on CVR energy savings and feeder power quality. In order to analyze the CVR benefit and PQS, an annual simulation was conducted for each scenario.« less

  12. Development and user validation of driving tasks for a power wheelchair simulator.

    PubMed

    Archambault, Philippe S; Blackburn, Émilie; Reid, Denise; Routhier, François; Miller, William C

    2017-07-01

    Mobility is important for participation in daily activities and a power wheelchair (PW) can improve quality of life of individuals with mobility impairments. A virtual reality simulator may be helpful in complementing PW skills training, which is generally seen as insufficient by both clinicians and PW users. To this end, specific, ecologically valid activities, such as entering an elevator and navigating through a shopping mall crowd, have been added to the McGill wheelchair (miWe) simulator through a user-centred approach. The objective of this study was to validate the choice of simulated activities in a group of newly trained PW users. We recruited 17 new PW users, who practiced with the miWe simulator at home for two weeks. They then related their experience through the Short Feedback Questionnaire, the perceived Ease of Use Questionnaire, and semi-structured interviews. Participants in general greatly appreciated their experience with the simulator. During the interviews, this group made similar comments about the activities as our previous group of expert PW users had done. They also insisted on the importance of realism in the miWe activities, for their use in training. A PW simulator may be helpful if it supports the practice of activities in specific contexts (such as a bathroom or supermarket), to complement the basic skills training received in the clinic (such as driving forward, backward, turning, and avoiding obstacles). Implications for Rehabilitation New power wheelchair users appreciate practicing on a virtual reality simulator and find the experience useful when the simulated diving activities are realistic and ecologically valid. User-centred development can lead to simulated power wheelchair activities that adequately capture everyday driving challenges experienced in various environmental contexts.

  13. Opportunities for Wind Power In Low- and Mid-Quality Resource Regions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lantz, Eric; Mai, Trieu; Heimiller, Donna

    2016-05-25

    In this presentation for American Wind Energy Association (AWEA) WINDPOWER 2016 conference, the authors discuss wind power today in low and mid-quality resource regions, the anticipated role of wind power in the future electric sector, market potential in low and mid-quality resource regions, and anticipated innovations to capture that market potential.

  14. Antioxidant Activities of Lactic Acid Bacteria for Quality Improvement of Fermented Sausage.

    PubMed

    Zhang, Yulong; Hu, Ping; Lou, Lijiao; Zhan, Jianlong; Fan, Min; Li, Dan; Liao, Qianwei

    2017-12-01

    Lactobacillus curvatus (SR6) and Lactobacillus paracasei (SR10-1) were assessed for their antioxidant activities and inoculated into sausages to investigate their effects on quality during fermentation. The results showed that L. curvatus SR6 had better DPPH• scavenging activity (59.67% ± 6.68%) and reducing power (47.31% ± 4.62%) and L. paracasei SR10-1 had better OH• scavenging activity (285.67% ± 2.00%) and anti-lipid peroxidation capacity (63.89% ± 0.93%). The superoxide dismutase activity of the cell culture fluid was greater than 47.00 U/mL, and the catalase activity of the cell-free extracts was greater than 1.00 U/mL. In the sausage model, lactic acid bacteria rapidly became the dominant microflora and reduced the moisture content, water activity, nitrite, and pH. The bacteria significantly enhanced the antioxidant activity of the sausage extracts, which improved the sensory characteristics and safety of the sausages. These results illustrate that both strains have excellent antioxidant activities and can be used as antioxidant starters in fermented meat products. The study illustrated the antioxidant and antioxidase activities of Lactobacillus curvatus SR6 and Lactobacillus paracasei SR10-1 and demonstrated the changes in the quality characteristics and antioxidant activities of fermented sausages. The findings provide valuable information for the meat industry on the application of functional starters in fermented meat products. © 2017 Institute of Food Technologists®.

  15. Assessment for water quality by artificial neural network in Daya Bay, South China Sea.

    PubMed

    Wu, Mei-Lin; Wang, You-Shao; Gu, Ji-Dong

    2015-10-01

    In this study, artificial neural network such as a self-organizing map (SOM) was used to assess for the effects caused by climate change and human activities on the water quality in Daya Bay, South China Sea. SOM has identified the anthropogenic effects and seasonal characters of water quality. SOM grouped the four seasons as four groups (winter, spring, summer and autumn). The Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on the water quality in Daya Bay. Spatial pattern is mainly related to anthropogenic activities and hydrodynamics conditions. In spatial characteristics, the water quality in Daya Bay was divided into two groups by chemometrics. The monitoring stations (S3, S8, S10 and S11) were in these area (Dapeng Ao, Aotou Harbor) and northeast parts of Daya Bay, which are areas of human activity. The thermal pollution has been observed near water body in Daya Bay Nuclear Power Plant (S5). The rest of the monitoring sites were in the south, central and eastern parts of Daya Bay, which are areas that experience water exchanges from South China Sea. The results of this study may provide information on the spatial and temporal patterns in Daya Bay. Further research will be carry out more research concerning functional changes in the bay ecology with respect to changes in climatic factor, human activities and bay morphology in Daya Bay.

  16. Active Electrodes for Wearable EEG Acquisition: Review and Electronics Design Methodology.

    PubMed

    Xu, Jiawei; Mitra, Srinjoy; Van Hoof, Chris; Yazicioglu, Refet Firat; Makinwa, Kofi A A

    2017-01-01

    Active electrodes (AEs), i.e., electrodes with built-in readout circuitry, are increasingly being implemented in wearable healthcare and lifestyle applications due to AEs' robustness to environmental interference. An AE locally amplifies and buffers μV-level EEG signals before driving any cabling. The low output impedance of an AE mitigates cable motion artifacts, thus enabling the use of high-impedance dry electrodes for greater user comfort. However, developing a wearable EEG system, with medical grade signal quality on noise, electrode offset tolerance, common-mode rejection ratio, input impedance, and power dissipation, remains a challenging task. This paper reviews state-of-the-art bio-amplifier architectures and low-power analog circuits design techniques intended for wearable EEG acquisition, with a special focus on an AE system interfaced with dry electrodes.

  17. The impact of three recent coal-fired power plant closings on Pittsburgh air quality: A natural experiment.

    PubMed

    Russell, Marie C; Belle, Jessica H; Liu, Yang

    2017-01-01

    Relative to the rest of the United States, the region of southwestern Pennsylvania, including metropolitan Pittsburgh, experiences high ambient concentrations of fine particulate matter (PM 2.5 ), which is known to be associated with adverse respiratory and cardiovascular health impacts. This study evaluates whether the closing of three coal-fired power plants within the southwestern Pennsylvania region resulted in a significant decrease in PM 2.5 concentration. Both PM 2.5 data obtained from EPA ground stations in the study region and aerosol optical depth (AOD) data retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments onboard the Terra and Aqua satellites were used to investigate regional air quality from January 2011 through December 2014. The impact of the plant closings on PM 2.5 concentration and AOD was evaluated using a series of generalized additive models. The model results show that monthly fuel consumption of the Elrama plant, which closed in October of 2012, and monthly fuel consumption of both the Mitchell and Hatfield's Ferry plants, which closed in October of 2013, were significant predictors of both PM 2.5 concentration and AOD at EPA ground stations in the study region, after controlling for multiple meteorological factors and long-term, region-wide air quality improvements. The model's power to predict PM 2.5 concentration increased from an adjusted R 2 of 0.61 to 0.68 after excluding data from ground stations with higher uncertainty due to recent increases in unconventional natural gas extraction activities. After preliminary analyses of mean PM 2.5 concentration and AOD showed a downward trend following each power plant shutdown, results from a series of generalized additive models confirmed that the activity of the three plants that closed, measured by monthly fuel consumption, was highly significant in predicting both AOD and PM 2.5 at 12 EPA ground stations; further research on PM 2.5 emissions from unconventional natural gas extraction is needed. With many coal-fired power plants scheduled to close across the United States in the coming years, there is interest in the potential impact on regional PM 2.5 concentrations. In southwestern Pennsylvania, recent coal-fired power plant closings were coupled with a boom in unconventional natural gas extraction. Natural gas is currently seen as an economically viable bridge fuel between coal and renewable energy. This study provides policymakers with more information on the potential ambient concentration changes associated with coal-fired power plant closings as the nation's energy reliance shifts toward natural gas.

  18. Colour-Difference Measurement Method for Evaluation of Quality of Electrolessly Deposited Copper on Polymer after Laser-Induced Selective Activation

    PubMed Central

    Gedvilas, Mindaugas; Ratautas, Karolis; Kacar, Elif; Stankevičienė, Ina; Jagminienė, Aldona; Norkus, Eugenijus; Li Pira, Nello; Račiukaitis, Gediminas

    2016-01-01

    In this work a novel colour-difference measurement method for the quality evaluation of copper deposited on a polymer is proposed. Laser-induced selective activation (LISA) was performed onto the surface of the polycarbonate/acrylonitrile butadiene styrene (PC/ABS) polymer by using nanosecond laser irradiation. The laser activated PC/ABS polymer was copper plated by using the electroless copper plating (ECP) procedure. The sheet resistance measured by using a four-point probe technique was found to decrease by the power law with the colour-difference of the sample images after LISA and ECP procedures. The percolation theory of the electrical conductivity of the insulator conductor mixture has been adopted in order to explain the experimental results. The new proposed method was used to determine an optimal set of the laser processing parameters for best plating conditions. PMID:26960432

  19. Effect of Microwave Vacuum Drying on the Drying Characteristics, Color, Microstructure, and Antioxidant Activity of Green Coffee Beans.

    PubMed

    Dong, Wenjiang; Cheng, Ke; Hu, Rongsuo; Chu, Zhong; Zhao, Jianping; Long, Yuzhou

    2018-05-11

    The aim of this study is to investigate the effect of microwave vacuum drying (MVD) on the drying characteristics and quality attributes of green coffee beans. We specifically focused on the effective moisture diffusion coefficient ( D eff ), surface temperature, glass transition temperature ( T g ), water state, and microstructure. The kinetics of color changes during drying, total phenolic content (TPC), and antioxidant activity (DPPH, FRAP, and ABTS) were also characterized. Microwave power during MVD affected the porosity of coffee beans, their color, TPC, and antioxidant activity. The Allometric 1 model was the most suitable for simulating surface temperature rise kinetics. Thermal processing of green coffee beans resulted in increased b* , L* , Δ E , and TPC values, and greater antioxidant capacity. These findings may provide a theoretical reference for the technical improvement, mechanisms of flavor compound formation, and quality control of dried green coffee beans.

  20. Active fault databases: building a bridge between earthquake geologists and seismic hazard practitioners, the case of the QAFI v.3 database

    NASA Astrophysics Data System (ADS)

    García-Mayordomo, Julián; Martín-Banda, Raquel; Insua-Arévalo, Juan M.; Álvarez-Gómez, José A.; Martínez-Díaz, José J.; Cabral, João

    2017-08-01

    Active fault databases are a very powerful and useful tool in seismic hazard assessment, particularly when singular faults are considered seismogenic sources. Active fault databases are also a very relevant source of information for earth scientists, earthquake engineers and even teachers or journalists. Hence, active fault databases should be updated and thoroughly reviewed on a regular basis in order to keep a standard quality and uniformed criteria. Desirably, active fault databases should somehow indicate the quality of the geological data and, particularly, the reliability attributed to crucial fault-seismic parameters, such as maximum magnitude and recurrence interval. In this paper we explain how we tackled these issues during the process of updating and reviewing the Quaternary Active Fault Database of Iberia (QAFI) to its current version 3. We devote particular attention to describing the scheme devised for classifying the quality and representativeness of the geological evidence of Quaternary activity and the accuracy of the slip rate estimation in the database. Subsequently, we use this information as input for a straightforward rating of the level of reliability of maximum magnitude and recurrence interval fault seismic parameters. We conclude that QAFI v.3 is a much better database than version 2 either for proper use in seismic hazard applications or as an informative source for non-specialized users. However, we already envision new improvements for a future update.

  1. Community-based physical activity interventions among women: a systematic review

    PubMed Central

    Amiri Farahani, Leila; Asadi-Lari, Mohsen; Mohammadi, Eesa; Parvizy, Soroor; Haghdoost, Ali Akbar; Taghizadeh, Ziba

    2015-01-01

    Objective Review and assess the effectiveness of community-based physical activity interventions among women aged 18–65 years. Design Systematic review Methods To find relevant articles, the researcher selected reports published in English between 1 January 2000 and 31 March 2013. Systematic search was to find controlled-trial studies that were conducted to uncover the effect of community-based interventions to promote physical activity among women 18–65 years of age, in which physical activity was reported as one of the measured outcomes. The methodological quality assessment was performed using a critical appraisal sheet. Also, the levels of evidence were assessed for the types of interventions. Results The literature search identified nine articles. Four of the studies were randomised and the others studies had high methodological quality. There was no evidence, on the basis of effectiveness, for social cognitive theory-based interventions and inconclusive evidence of effectiveness for the rest of interventions. Conclusions There is insufficient evidence to assess the effectiveness of community-based interventions for enhancing physical activity among women. There is a need for high-quality randomised clinical trials with adequate statistical power to determine whether multicomponent and community-based intervention programmes increase physical activity among women, as well as to determine what type of interventions have a more effective and sustainable impact on women's physical activity. PMID:25833668

  2. High power broadband all fiber super-fluorescent source with linear polarization and near diffraction-limited beam quality.

    PubMed

    Ma, Pengfei; Huang, Long; Wang, Xiaolin; Zhou, Pu; Liu, Zejin

    2016-01-25

    In this manuscript, a high power broadband superfluorescent source (SFS) with linear polarization and near-diffraction-limited beam quality is achieved based on an ytterbium-doped (Yb-doped), all fiberized and polarization-maintained master oscillator power amplifier (MOPA) configuration. The MOPA structure generates a linearly polarized output power of 1427 W with a slope efficiency of 80% and a full width at half maximum (FWHM) of 11 nm, which is power scaled by an order of magnitude compared with the previously reported SFSs with linear polarization. In the experiment, both the polarization extinction ratio (PER) and beam quality (M(2) factor) are degraded little during the power scaling process. At maximal output power, the PER and M(2) factor are measured to be 19.1dB and 1.14, respectively. The root-mean-square (RMS) and peak-vale (PV) values of the power fluctuation at maximal output power are just 0.48% and within 3%, respectively. Further power scaling of the whole system is limited by the available pump sources. To the best of our knowledge, this is the first demonstration of kilowatt level broadband SFS with linear polarization and near-diffraction-limited beam quality.

  3. Finite volume analysis of temperature effects induced by active MRI implants with cylindrical symmetry: 1. Properly working devices.

    PubMed

    Busch, Martin H J; Vollmann, Wolfgang; Schnorr, Jörg; Grönemeyer, Dietrich H W

    2005-04-08

    Active Magnetic Resonance Imaging implants are constructed as resonators tuned to the Larmor frequency of a magnetic resonance system with a specific field strength. The resonating circuit may be embedded into or added to the normal metallic implant structure. The resonators build inductively coupled wireless transmit and receive coils and can amplify the signal, normally decreased by eddy currents, inside metallic structures without affecting the rest of the spin ensemble. During magnetic resonance imaging the resonators generate heat, which is additional to the usual one described by the specific absorption rate. This induces temperature increases of the tissue around the circuit paths and inside the lumen of an active implant and may negatively influence patient safety. This investigation provides an overview of the supplementary power absorbed by active implants with a cylindrical geometry, corresponding to vessel implants such as stents, stent grafts or vena cava filters. The knowledge of the overall absorbed power is used in a finite volume analysis to estimate temperature maps around different implant structures inside homogeneous tissue under worst-case assumptions. The "worst-case scenario" assumes thermal heat conduction without blood perfusion inside the tissue around the implant and mostly without any cooling due to blood flow inside vessels. The additional power loss of a resonator is proportional to the volume and the quality factor, as well as the field strength of the MRI system and the specific absorption rate of the applied sequence. For properly working devices the finite volume analysis showed only tolerable heating during MRI investigations in most cases. Only resonators transforming a few hundred mW into heat may reach temperature increases over 5 K. This requires resonators with volumes of several ten cubic centimeters, short inductor circuit paths with only a few 10 cm and a quality factor above ten. Using MR sequences, for which the MRI system manufacturer declares the highest specific absorption rate of 4 W/kg, vascular implants with a realistic construction, size and quality factor do not show temperature increases over a critical value of 5 K. The results show dangerous heating for the assumed "worst-case scenario" only for constructions not acceptable for vascular implants. Realistic devices are safe with respect to temperature increases. However, this investigation discusses only properly working devices. Ruptures or partial ruptures of the wires carrying the electric current of the resonance circuits or other defects can set up a power source inside an extremely small volume. The temperature maps around such possible "hot spots" should be analyzed in an additional investigation.

  4. Modelling voltage sag mitigation using dynamic voltage restorer and analyzing power quality issue

    NASA Astrophysics Data System (ADS)

    Ismail, Nor Laili; Hidzir, Hizrin Dayana Mohd; Thanakodi, Suresh; Nazar, Nazatul Shiema Moh; Ibrahim, Pungut; Ali, Che Ku Muhammad Sabri Che Ku

    2018-02-01

    Power quality problem which are arise due to a fault or a pulsed load can have caused an interruption of critical load. The modern power systems are becoming more sensitive to the quality of the power supplied by the utility company. Voltage sags and swells, flicker, interruptions, harmonic distortion and other distortion to the sinusoidal waveform are the examples of the power quality problems. The most affected due to these problems is industrial customers who use a lot of sensitive equipment. There has suffered a huge loss to these problems. Resulting of broken or damage equipment if voltage sag exceeds the sensitive threshold of the equipment. Thus, device such as Static Synchronous Compensator (STATCOM) and Dynamic Voltage Restorer (DVR) has been created to solve this problem among users. DVR is a custom power device that most effective and efficient. This paper intended to report the DVR operations during voltage sag compensation.

  5. An Improved Power Quality Based Sheppard-Taylor Converter Fed BLDC Motor Drive

    NASA Astrophysics Data System (ADS)

    Singh, Bhim; Bist, Vashist

    2015-12-01

    This paper deals with the design and analysis of a power factor correction based Sheppard-Taylor converter fed brushless dc motor (BLDCM) drive. The speed of the BLDCM is controlled by adjusting the dc link voltage of the voltage source inverter (VSI) feeding BLDCM. Moreover, a low frequency switching of the VSI is used for electronically commutating the BLDCM for reduced switching losses. The Sheppard-Taylor converter is designed to operate in continuous conduction mode to achieve an improved power quality at the ac mains for a wide range of speed control and supply voltage variation. The BLDCM drive is designed and its performance is simulated in a MATLAB/Simulink environment to achieve the power quality indices within the limits of the international power quality standard IEC-61000-3-2.

  6. Formation of short high-power laser radiation pulses in excimer mediums

    NASA Astrophysics Data System (ADS)

    Losev, V. F., Sr.; Ivanov, N. G.; Panchenko, Yu. N.

    2007-06-01

    Presently an excimer mediums continue are examined as one of variants for formation of powerful and over powerful pulses of laser radiation with duration from units of nanosecond up to tens femtosecond. The researches on such powerful installations as "NIKE" (USA) and << SUPER ASHURA >>, Japan) proceed in this direction. The main advantage of excimer mediums is the opportunity to work in a frequency mode, absence of restriction on the size of active area, high uniformity of a gas working medium, high efficiency (up to 10 %) and wide spectral range of laser radiation (KrF, XeCl ~ 2nm, XeF (C-A), Xe IICl ~ 50-100 nanometers). Research in area of high quality laser beams formation in excimer mediums and its amplification in high power amplifiers are carried out the long time in Institute of High Current Electronics SB RAS, Tomsk, Russia. The wide aperture XeCl laser system of MELS-4k is used for these investigations. Last time we take part in program on development of high power excimer laser system with a petawatt level of power. This system supposes the formation and amplification high quality laser beams with different pulse duration from units of nanosecond up to tens femtosecond. We research the possibility of laser beams formation in excimer mediums with ps-ns pulse duration having the low noise and divergence near to diffraction limit. In other hand, we are developing the wide aperture XeF(C-A) amplifier with optical pump on base electron accelerator. According to our estimations of the XeF(C-A) amplifier based on the converter of e-beam energy to the Xe II* fluorescence at 172 nm will allow to obtain up to 100 TW peak power in a 30 fs pulse.

  7. "Electric Power for Rural Growth: How Electricity Affects Rural Life in Developing Countries," by Douglas F. Barnes. [Book Review].

    ERIC Educational Resources Information Center

    Lodwick, Dora G.; McIntosh, William A., Ed.

    1989-01-01

    Reviews a book assessing the effects of central grid rural electrification on the social and economic development of 192 communities in India and Colombia. The study examines the impact on agricultural productivity (through increased irrigation), the quality of life of women and children, business activities, and regional inequities. (SV)

  8. Exploring the Psychosocial Impact of Wheelchair and Contextual Factors on Quality of Life of People with Neuromuscular Disorders.

    PubMed

    Pousada García, Thais; Groba González, Betania; Nieto Rivero, Laura; Pereira Loureiro, Javier; Díez Villoria, Emiliano; Pazos Sierra, Alejandro

    2015-01-01

    Neuromuscular disorders (NMDs) are a group of heterogeneous diseases that show differences in incidence, hereditary, etiology, prognosis, or functional impairments. Wheelchair use (manual or powered) is influenced by several factors, including personal and contextual factors, and comprehensive evaluation of their impact is required in order to optimize prescription and provision of wheelchairs. The authors therefore assessed the influence of wheelchair use on the quality of life (QoL) of 60 participants with NMD using the Psychosocial Impact of Assistive Devices Scale (PIADS). The Functional Independence Measure (FIM) and a specially developed questionnaire were used to obtain information about contextual factors and participants' activity profile of activities of the participants. The results showed that using a wheelchair has psychosocial benefits, with the main determinants of benefit being type of wheelchair (powered), non-ambulation ability, and independence in mobility. Ensuring a good match between user and assistive technology (AT; e.g., wheelchair), as well as the effectiveness of the particular device, will increase the likelihood that the user will adopt it and use it effectively in daily life. Clinical prescription of AT would be improved by making appropriate use of outcome measures.

  9. Lead/acid batteries in systems to improve power quality

    NASA Astrophysics Data System (ADS)

    Taylor, P.; Butler, P.; Nerbun, W.

    Increasing dependence on computer technology is driving needs for extremely high-quality power to prevent loss of information, material, and workers' time that represent billions of dollars annually. This cost has motivated commercial and Federal research and development of energy storage systems that detect and respond to power-quality failures in milliseconds. Electrochemical batteries are among the storage media under investigation for these systems. Battery energy storage systems that employ either flooded lead/acid or valve-regulated lead/acid battery technologies are becoming commercially available to capture a share of this emerging market. Cooperative research and development between the US Department of Energy and private industry have led to installations of lead/acid-based battery energy storage systems to improve power quality at utility and industrial sites and commercial development of fully integrated, modular battery energy storage system products for power quality. One such system by AC Battery Corporation, called the PQ2000, is installed at a test site at Pacific Gas and Electric Company (San Ramon, CA, USA) and at a customer site at Oglethorpe Power Corporation (Tucker, GA, USA). The PQ2000 employs off-the-shelf power electronics in an integrated methodology to control the factors that affect the performance and service life of production-model, low-maintenance, flooded lead/acid batteries. This system, and other members of this first generation of lead/acid-based energy storage systems, will need to compete vigorously for a share of an expanding, yet very aggressive, power quality market.

  10. Transfer-printing of active layers to achieve high quality interfaces in sequentially deposited multilayer inverted polymer solar cells fabricated in air

    PubMed Central

    Vohra, Varun; Anzai, Takuya; Inaba, Shusei; Porzio, William; Barba, Luisa

    2016-01-01

    Abstract Polymer solar cells (PSCs) are greatly influenced by both the vertical concentration gradient in the active layer and the quality of the various interfaces. To achieve vertical concentration gradients in inverted PSCs, a sequential deposition approach is necessary. However, a direct approach to sequential deposition by spin-coating results in partial dissolution of the underlying layers which decreases the control over the process and results in not well-defined interfaces. Here, we demonstrate that by using a transfer-printing process based on polydimethylsiloxane (PDMS) stamps we can obtain increased control over the thickness of the various layers while at the same time increasing the quality of the interfaces and the overall concentration gradient within the active layer of PSCs prepared in air. To optimize the process and understand the influence of various interlayers, our approach is based on surface free energy, spreading parameters and work of adhesion calculations. The key parameter presented here is the insertion of high quality hole transporting and electron transporting layers, respectively above and underneath the active layer of the inverted structure PSC which not only facilitates the transfer process but also induces the adequate vertical concentration gradient in the device to facilitate charge extraction. The resulting non-encapsulated devices (active layer prepared in air) demonstrate over 40% increase in power conversion efficiency with respect to the reference spin-coated inverted PSCs. PMID:27877901

  11. Enhancement of water removing and the quality of fried purple-fleshed sweet potato in the vacuum frying by combined power ultrasound and microwave technology.

    PubMed

    Su, Ya; Zhang, Min; Bhandari, Bhesh; Zhang, Weiming

    2018-06-01

    The combination of ultrasound and microwave in vacuum frying system was investigated to achieve higher drying efficiency and quality attributes of fried products. Purple-fleshed potato were used as test specimen and different power levels of microwave (0 W, 600 W, 800 W) and ultrasound (0 W, 300 W, 600 W) during vacuum frying. Drying kinetics, dielectric properties, moisture state variation and quality attributes of fried samples were measured in a vacuum frying (VF), and an innovatively designed ultrasound and microwave assisted vacuum frying (USMVF) equipment. The USMVF process markedly increased the moisture evaporation rate and effective moisture diffusivity compared to VF process. The oil uptake was reduced by about 16-34%, the water activity and the shrinkage was lowered, the texture (crispness) and the color of fried samples were greatly improved. The higher ultrasound and microwave power level in USMVF made a greater improvement. The total anthocyanin levels and retention of fried purple-fleshed potato chips was the highest (123.52 mg/100 g solids and 79.51% retention, respectively) among all treatments in US600M800VF process. The SEM analysis revealed a more porous and disruption microstructure in USMVF sample. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Biomass "Green" Power Vs. Coal "Traditional" Power: Who is the Largest Emitter in Humboldt County and How Should Regulations be Addressed?

    NASA Astrophysics Data System (ADS)

    Zurawski, A. M.

    2016-12-01

    The objective of this research is to study how emissions from a fossil fuel power plant compare to emissions from a biomass power plant, and how these results can be used to improve current air-quality regulations. Outdoor air quality transcends national and political boundaries. Air pollution monitoring is essential to maintaining quality of life for humans and ecosystems. Due to anthropogenic disturbances (primarily related to burning of fossil fuels), air- quality management has become a priority on a long list of environmental issues. Quantifying and monitoring the largest emitters of greenhouse gases and toxic pollutants is crucial to the creation and enforcement of appropriate environmental protection regulations. Emissions data were collected from January 2010 to January 2016 from sensors installed close to a biomass power plant, and sensors installed close to a fossil fuel and natural gas power plant, in Humboldt County, California. In Humboldt County, where air quality serves as a baseline of air pollution in the United States, data showed that the "green" biomass power plant emitted higher levels of particulate matter compared to the fossil fuel power plant. Additionally, the biomass power plant showed levels of CO2, NOx, and SO2 emissions that suggest its place as a "green" power source should be reconsidered. Our research suggests that regulations need to be reconsidered given the potential for high pollutant emissions from biomass plants.

  13. Association between body composition and disease activity in rheumatoid arthritis. A systematic review.

    PubMed

    Alvarez-Nemegyei, José; Buenfil-Rello, Fátima Annai; Pacheco-Pantoja, Elda Leonor

    2016-01-01

    Reports regarding the association between body composition and inflammatory activity in rheumatoid arthritis (RA) have consistently yielded contradictory results. To perform a systematic review on the association between overweight/obesity and inflammatory activity in RA. FAST approach: Article search (Medline, EBSCO, Cochrane Library), followed by abstract retrieval, full text review and blinded assessment of methodological quality for final inclusion. Because of marked heterogeneity in statistical approach and RA activity assessment method, a meta-analysis could not be done. Results are presented as qualitative synthesis. One hundred and nineteen reports were found, 16 of them qualified for full text review. Eleven studies (8,147 patients; n range: 37-5,161) approved the methodological quality filter and were finally included. Interobserver agreement for methodological quality score (ICC: 0.93; 95% CI: 0.82-0.98; P<.001) and inclusion/rejection decision (k 1.00, P>.001) was excellent. In all reports body composition was assessed by BMI; however a marked heterogeneity was found in the method used for RA activity assessment. A significant association between BMI and RA activity was found in 6 reports having larger mean sample size: 1,274 (range: 140-5,161). On the other hand, this association was not found in 5 studies having lower mean sample size: 100 (range: 7-150). The modulation of RA clinical status by body fat mass is suggested because a significant association was found between BMI and inflammatory activity in those reports with a trend toward higher statistical power. The relationship between body composition and clinical activity in RA requires be approached with further studies with higher methodological quality. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  14. Quality Control of Gamma Irradiated Dwarf Mallow (Malva neglecta Wallr.) Based on Color, Organic Acids, Total Phenolics and Antioxidant Parameters.

    PubMed

    Pinela, José; Barros, Lillian; Antonio, Amilcar L; Carvalho, Ana Maria; Oliveira, M Beatriz P P; Ferreira, Isabel C F R

    2016-04-08

    This study addresses the effects of gamma irradiation (1, 5 and 8 kGy) on color, organic acids, total phenolics, total flavonoids, and antioxidant activity of dwarf mallow (Malva neglecta Wallr.). Organic acids were analyzed by ultra fast liquid chromatography (UFLC) coupled to a photodiode array (PDA) detector. Total phenolics and flavonoids were measured by the Folin-Ciocalteu and aluminium chloride colorimetric methods, respectively. The antioxidant activity was evaluated based on the DPPH(•) scavenging activity, reducing power, β-carotene bleaching inhibition and thiobarbituric acid reactive substances (TBARS) formation inhibition. Analyses were performed in the non-irradiated and irradiated plant material, as well as in decoctions obtained from the same samples. The total amounts of organic acids and phenolics recorded in decocted extracts were always higher than those found in the plant material or hydromethanolic extracts, respectively. The DPPH(•) scavenging activity and reducing power were also higher in decocted extracts. The assayed irradiation doses affected differently the organic acids profile. The levels of total phenolics and flavonoids were lower in the hydromethanolic extracts prepared from samples irradiated at 1 kGy (dose that induced color changes) and in decocted extracts prepared from those irradiated at 8 kGy. The last samples also showed a lower antioxidant activity. In turn, irradiation at 5 kGy favored the amounts of total phenolics and flavonoids. Overall, this study contributes to the understanding of the effects of irradiation in indicators of dwarf mallow quality, and highlighted the decoctions for its antioxidant properties.

  15. The effect of thermal de-phasing on the beam quality of a high-power single-pass second harmonic generation

    NASA Astrophysics Data System (ADS)

    Sadat Hashemi, Somayeh; Ghavami Sabouri, Saeed; Khorsandi, Alireza

    2018-04-01

    We present a theoretical model in order to study the effect of a thermally loaded crystal on the quality of a second-harmonic (SH) beam generated in a high-power pumping regime. The model is provided based on using a particular structure of oven considered for MgO:PPsLT nonlinear crystal to compensate for the thermal de-phasing effect that as the pumping power reaches up to 50 W degrades the conversion efficiency and beam quality of the interacting beams. Hereupon, the quality of fundamental beam is involved in the modeling to investigate the final effect on the beam quality of generated SH beam. Beam quality evaluation is subsequently simulated using Hermite-Gaussian modal decomposition approach for a range of fundamental beam qualities varied from 1 to 3 and for different levels of input powers. To provide a meaningful comparison numerical simulation is correlated with real data deduced from a high-power SH generation (SHG) experimental device. It is found that when using the open-top oven scheme and fixing the fundamental M 2-factor at nearly 1, for a range of input powers changing from 15 to 30 W, the M 2-factor of SHG beam is degraded from 9% to 24%, respectively, confirming very good consistency with the reported experimental results.

  16. High power far-infrared optical parametric oscillator with high beam quality

    NASA Astrophysics Data System (ADS)

    Qian, Chuan-Peng; Shen, Ying-Jie; Dai, Tong-Yu; Duan, Xiao-Ming; Yao, Bao-Quan

    2016-11-01

    A high power ZnGeP2 (ZGP) optical parametric oscillator (OPO) with good beam quality pumped by a Q-switched Ho:YAG laser was demonstrated. The maximum output power of the ZGP OPO with a four-mirror ring cavity was about 5.04 W around 8.1 μm with 83.9 W Ho incident pump power, corresponding to a slope efficiency of 9.2 %. The ZGP OPO produced 36.0 ns far-IR pulse laser in the 8.0-8.3 μm spectral regions. The beam quality was measured to be M2 1.6 at the highest output power.

  17. Reactive power and voltage control strategy based on dynamic and adaptive segment for DG inverter

    NASA Astrophysics Data System (ADS)

    Zhai, Jianwei; Lin, Xiaoming; Zhang, Yongjun

    2018-03-01

    The inverter of distributed generation (DG) can support reactive power to help solve the problem of out-of-limit voltage in active distribution network (ADN). Therefore, a reactive voltage control strategy based on dynamic and adaptive segment for DG inverter is put forward to actively control voltage in this paper. The proposed strategy adjusts the segmented voltage threshold of Q(U) droop curve dynamically and adaptively according to the voltage of grid-connected point and the power direction of adjacent downstream line. And then the reactive power reference of DG inverter can be got through modified Q(U) control strategy. The reactive power of inverter is controlled to trace the reference value. The proposed control strategy can not only control the local voltage of grid-connected point but also help to maintain voltage within qualified range considering the terminal voltage of distribution feeder and the reactive support for adjacent downstream DG. The scheme using the proposed strategy is compared with the scheme without the reactive support of DG inverter and the scheme using the Q(U) control strategy with constant segmented voltage threshold. The simulation results suggest that the proposed method has a significant improvement on solving the problem of out-of-limit voltage, restraining voltage variation and improving voltage quality.

  18. Improving the beam quality of high-power laser diodes by introducing lateral periodicity into waveguides

    NASA Astrophysics Data System (ADS)

    Sobczak, Grzegorz; DÄ browska, ElŻbieta; Teodorczyk, Marian; Kalbarczyk, Joanna; MalÄ g, Andrzej

    2013-01-01

    Low quality of the optical beam emitted by high-power laser diodes is the main disadvantage of these devices. The two most important reasons are highly non-Gaussian beam profile with relatively wide divergence in the junction plane and the filamentation effect. Designing laser diode as an array of narrow, close to each other single-mode waveguides is one of the solutions to this problem. In such devices called phase locked arrays (PLA) there is no room for filaments formation. The consequence of optical coupling of many single-mode waveguides is the device emission in the form of few almost diffraction limited beams. Because of losses in regions between active stripes the PLA devices have, however, somewhat higher threshold current and lower slope efficiencies compared to wide-stripe devices of similar geometry. In this work the concept of the high-power laser diode resonator consisted of joined PLA and wide stripe segments is proposed. Resulting changes of electro-optical characteristics of PLA are discussed. The devices are based on the asymmetric heterostructure designed for improvement of the catastrophic optical damage threshold as well as thermal and electrical resistances. Due to reduced distance from the active layer to surface in this heterostructure, better stability of current (and gain) distribution with changing drive level is expected. This could lead to better stability of optical field distribution and supermodes control. The beam divergence reduction in the direction perpendicular of the junction plane has been also achieved.

  19. Development and flight evaluation of an augmented stability active controls concept with a small horizontal tail

    NASA Technical Reports Server (NTRS)

    Rising, J. J.; Kairys, A. A.; Maass, C. A.; Siegart, C. D.; Rakness, W. L.; Mijares, R. D.; King, R. W.; Peterson, R. S.; Hurley, S. R.; Wickson, D.

    1982-01-01

    A limited authority pitch active control system (PACS) was developed for a wide body jet transport (L-1011) with a flying horizontal stabilizer. Two dual channel digital computers and the associated software provide command signals to a dual channel series servo which controls the stabilizer power actuators. Input sensor signals to the computer are pitch rate, column-trim position, and dynamic pressure. Control laws are given for the PACS and the system architecture is defined. The piloted flight simulation and vehicle system simulation tests performed to verify control laws and system operation prior to installation on the aircraft are discussed. Modifications to the basic aircraft are described. Flying qualities of the aircraft with the PACS on and off were evaluated. Handling qualities for cruise and high speed flight conditions with the c.g. at 39% mac ( + 1% stability margin) and PACS operating were judged to be as good as the handling qualities with the c.g. at 25% (+15% stability margin) and PACS off.

  20. Evaluation of nutritional quality and antioxidant potential of pigeonpea genotypes.

    PubMed

    Sekhon, Japjot; Grewal, Satvir Kaur; Singh, Inderjit; Kaur, Jagmeet

    2017-10-01

    Three released cultivars, forty four advance breeding lines and three wild species of pigeonpea ( Cajanus cajan L. Millsp) were evaluated for nutritional, antinutritional traits and antioxidant potential so as to identify promising genotypes. The average content of total soluble sugars, starch and total soluble proteins was found to be 43.66, 360.51 and 204.54 mg/g, respectively. Antioxidant potential in terms of free radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), reducing power, hydroxyl radical scavenging activity and superoxide anion radical scavenging activity was estimated. The diversity was observed in genotypes with all the traits. AL 1960, AL 2000, AL 2009 and AL 2046 had high total soluble proteins, medium antinutritional factors and good antioxidant potential. AL 201, AL 1931, AL 1932, AL 1960, AL 2046, AL 2049 and AL 2060 had good nutritional value as protein and starch content ranged from 20 to 23 and 42 to 52%, respectively. Wild species C. scarabaeoides 1CP15683/W15 had lower carbohydrates, proteins, and antinutritional traits while high antioxidant potential due to high total phenols, DPPH, FRAP and reducing power. The diversity observed in genotypes with all the traits could be further used to develop nutritionally important genotypes.

  1. Simultaneous remote measurement of CO2 concentration, humidity and temperature with a matrix of optical fiber sensors

    NASA Astrophysics Data System (ADS)

    Wysokiński, Karol; Filipowicz, Marta; Stańczyk, Tomasz; Lipiński, Stanisław; Napierała, Marek; Murawski, Michał; Nasiłowski, Tomasz

    2017-10-01

    A matrix of optical fiber sensors eligible for remote measurements is reported in this paper. The aim of work was to monitor the air quality with a device, which does not need any electricity on site of the measurement. The matrix consists of several sensors detecting carbon dioxide concentration, relative humidity and temperature. Sensors utilize active optical materials, which change their color when exposed to varied conditions. All the sensors are powered with standard light emitting diodes. Light is transmitted by an optical fiber from the light source and then it reaches the active layer which changes its color, when the conditions change. This results in a change of attenuation of light passing through the active layer. Modified light is then transmitted by another optical fiber to the detector, where simple photoresistor is used. It is powered by a stabilized DC power supply and the current is measured. Since no expensive elements are needed to manufacture such a matrix of sensors, its price may be competitive to the price of the devices already available on the market, while the matrix also exhibits other valuable properties.

  2. Effect of drying methods on total antioxidant capacity of bitter gourd (momordica charantia) fruit

    NASA Astrophysics Data System (ADS)

    Tan, Ee Shian; Abdullah, Aminah; Maskat, Mohammad Yusof

    2013-11-01

    The effect of thermal and non-thermal drying methods on hydrophilic and lipophilic antioxidant capacities of bitter gourd fruit was investigated in this study. The bitter gourd fruits were dried by following methods: (i) oven drying 40°C, (ii) oven drying 50°C, (iii) oven drying 60°C, (iv) microwave drying (medium low power), (v) microwave drying (medium power) and (vi) freeze drying. Pure acetone and hexane were used to extract the hydrophilic and lipophilic antioxidant compounds from dried bitter gourd fruits. Freeze dried extracts reported to have highest values in DPPH scavenging activity (hydrophilic and lipophilic fractions), FRAP (lipophilic fraction) and TPC (hydrophilic and lipophilic fraction). Thermal drying slightly increased the values of DPPH scavenging activity, FRAP and TPC assays for hydrophilic extracts. Results concluded bitter gourd fruit is a good source of natural antioxidants and its total antioxidant quality was most preserved by freeze drying. Additionally, the higher value reported in DPPH scavenging activity, FRAP and TPC assays for lipophilic extracts than the hydrophilic extracts suggested that the lipophilic antioxidant compounds of bitter gourd fruit might possess stronger antioxidant power than its counterpart.

  3. Effect of Hartha and Najibia power plants on water quality indices of Shatt Al-Arab River, south of Iraq

    NASA Astrophysics Data System (ADS)

    Al-Aboodi, Ali H.; Abbas, Sarmad A.; Ibrahim, Husham T.

    2018-05-01

    The main object of this research is to assess the water quality of Shatt Al-Arab River and its suitability for various purposes near power plants (Hartha and Najibia) through physical and chemical analysis [temperature, pH, EC, Cl-, Na+, K+, Ca+2, Mg+2, HCO3 -, NO3 -, SO 4 -2 , Fe+, total alkalinity, total hardness, biological oxygen demand (BOD5), NH4 +, and NO2 -] using water quality index (WQI), organic pollution index (OPI), sodium adsorption ratio (SAR), and percentage of sodium ion (Na%) during the dry season (August, 2016) and the wet season (January, 2017). WQI of Shatt Al-Arab falls under very poor quality during summer season, while it ranges from very poor quality to unsuitable for drinking purposes during winter season. There is a clear effect of power plants on water quality. Hartha and Najibia power plants contribute to the deterioration of water quality by increasing the percentage ratio of WQI near these plants by 13.22 and 9.69%, respectively, compared to the north sites of these plants during summer season. The percentage ratios of increased WQI near Hartha and Najibia power plants compared to the north sites of these plants are 17.93 and 15.92%, respectively, during winter season. Water quality of Shatt Al-Arab falls under a high level of organic pollution during the summer and winter seasons. There is a slight effect by the power plants on the OPI. Hartha and Najibia power plants contributed to the change of the OPI by 10% compared to the north site of Hartha power plant. According to the comparison between the SAR values which represent the suitability of water for serve irrigation purposes and SAR values of Shatt Al-Arab, all sites lie in the first class (excellent). According to Na+%, the type of surface water in the studied area lies in good class during winter season and permissible class during summer season.

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Touati, Said; Chennai, Salim; Souli, Aissa

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

  5. The impact of turbulent renewable energy production on power grid stability and quality

    NASA Astrophysics Data System (ADS)

    Schmietendorf, Katrin; Peinke, Joachim; Kamps, Oliver

    2017-11-01

    Feed-in fluctuations induced by renewables are one of the key challenges to the stability and quality of electrical power grids. In particular short-term fluctuations disturb the system on a time scale, on which load balancing does not operate yet and the system is intrinsically governed by self-organized synchronization. Wind and solar power are known to be strongly non-Gaussian with intermittent increment statistics in these time scales. We investigate the impact of short-term wind fluctuations on the basis of a Kuramoto-like power grid model considering stability in terms of desynchronization and frequency and voltage quality aspects. We present a procedure to generate realistic feed-in fluctuations with temporal correlations, Kolmogorov power spectrum and intermittent increments. By comparison to correlated Gaussian noise of the same spectrum and Gaussian white noise, we found out that while the correlations are essential to capture the likelihood of severe outages, the intermittent nature of wind power has significant consequences on power quality: intermittency is directly transferred into frequency and voltage fluctuations yielding a novel type of fluctuations, which is beyond engineering status of knowledge.

  6. The effects of TGG crystal length on output power and beam quality of a unidirectional ring Nd:YVO4 laser with and without second harmonic generation

    NASA Astrophysics Data System (ADS)

    Ahmadi, A.; Avazpour, A.; Nadgaran, H.; Mousavi, M.

    2018-04-01

    The effect of terbium gallium garnet (TGG ) crystal length on 1064 and 532 nm output powers and beam quality of a unidirectional ring Nd:YVO4 laser is investigated. In the case of 1064 nm (without nonlinear crystal), the laser output power without considerating the effect of TGG crystal was computed theoretically. Then three TGG crystals with different lengths were placed in the laser setup one by one. A systematic decrease in output power was observed by increasing the TGG crystal length. The experiment was repeated in the case of 532 nm. It was found that in a 532 nm laser, higher laser efficiency and small beam quality degradation can be achieved by increasing the TGG crystal length leading to a 5.7 W green laser with 27 W pump power. The power stability and beam quality were 0.8% for 30 min and less than 1.3, respectively.

  7. Advanced Grid Simulator for Multi-Megawatt Power Converter Testing and Certification

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koralewicz, Przemyslaw; Gevorgian, Vahan; Wallen, Robb

    2017-02-16

    Grid integration testing of inverter-coupled renewable energy technologies is an essential step in the qualification of renewable energy and energy storage systems to ensure the stability of the power system. New types of devices must be thoroughly tested and validated for compliance with relevant grid codes and interconnection requirements. For this purpose, highly specialized custom-made testing equipment is needed to emulate various types of realistic grid conditions that are required by certification bodies or for research purposes. For testing multi-megawatt converters, a high power grid simulator capable of creating controlled grid conditions and meeting both power quality and dynamic characteristicsmore » is needed. This paper describes the new grid simulator concept based on ABB's medium voltage ACS6000 drive technology that utilizes advanced modulation and control techniques to create an unique testing platform for various multi-megawatt power converter systems. Its performance is demonstrated utilizing the test results obtained during commissioning activities at the National Renewable Energy Laboratory in Colorado, USA.« less

  8. High-efficient Nd:YAG microchip laser for optical surface scanning

    NASA Astrophysics Data System (ADS)

    Šulc, Jan; Jelínková, Helena; Nejezchleb, Karel; Škoda, Václav

    2017-12-01

    A CW operating, compact, high-power, high-efficient diode pumped 1064nm laser, based on Nd:YAG active medium, was developed for optical surface scanning and mapping applications. To enhance the output beam quality, laser stability, and compactness, a microchip configuration was used. In this arrangement the resonator mirrors were deposited directly on to the laser crystal faces. The Nd-doping concentration was 1 at.% Nd/Y. The Nd:YAG crystal was 5mm long. The laser resonator without pumping radiation recuperation was investigated {the output coupler was transparent for pumping radiation. For the generated laser radiation the output coupler reflectivity was 95%@1064 nm. The diameter of the samples was 5 mm. For the laser pumping two arrangements were investigated. Firstly, a fibre coupled laser diode operating at wavelength 808nm was used in CW mode. The 400 ¹m fiber was delivering up to 14W of pump power amplitude to the microchip laser. The maximum CW output power of 7.2W @ 1064nm in close to TEM00 beam was obtained for incident pumping power 13.7W @ 808 nm. The differential efficiency in respect to the incident pump power reached 56 %. Secondly, a single-emitter, 1W laser diode operating at 808nm was used for Nd:YAG microchip pumping. The laser pumping was directly coupled into the microchip laser using free-space lens optics. Slope efficiency up to 70% was obtained in stable, high-quality, 1064nm laser beam with CW power up to 350mW. The system was successfully used for scanning of super-Gaussian laser mirrors reflectivity profile.

  9. 11 W narrow linewidth laser source at 780nm for laser cooling and manipulation of Rubidium

    NASA Astrophysics Data System (ADS)

    Sané, S. S.; Bennetts, S.; Debs, J. E.; Kuhn, C. C. N.; McDonald, G. D.; Altin, P. A.; Close, J. D.; Robins, N. P.

    2012-04-01

    We present a narrow linewidth continuous laser source with over 11 Watts of output power at 780nm, based on single-pass frequency doubling of an amplified 1560nm fibre laser with 36% efficiency. This source offers a combination of high power, simplicity, mode quality and stability. Without any active stabilization, the linewidth is measured to be below 10kHz. The fibre seed is tunable over 60GHz, which allows access to the D2 transitions in 87Rb and 85Rb, providing a viable high-power source for laser cooling as well as for large-momentum-transfer beamsplitters in atom interferometry. Sources of this type will pave the way for a new generation of high flux, high duty-cycle degenerate quantum gas experiments.

  10. Application of semi-active RFID power meter in automatic verification pipeline and intelligent storage system

    NASA Astrophysics Data System (ADS)

    Chen, Xiangqun; Huang, Rui; Shen, Liman; chen, Hao; Xiong, Dezhi; Xiao, Xiangqi; Liu, Mouhai; Xu, Renheng

    2018-03-01

    In this paper, the semi-active RFID watt-hour meter is applied to automatic test lines and intelligent warehouse management, from the transmission system, test system and auxiliary system, monitoring system, realize the scheduling of watt-hour meter, binding, control and data exchange, and other functions, make its more accurate positioning, high efficiency of management, update the data quickly, all the information at a glance. Effectively improve the quality, efficiency and automation of verification, and realize more efficient data management and warehouse management.

  11. Bulk shielding facility quarterly report, October, November, and December 1976

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hurt, III, S. S.; Lance, E. D.; Thomas, J. R.

    1977-08-01

    The BSR operated at an average power level of 1,836 kw for 78.01 percent of the time during October, November, and December. Water-quality control in both the reactor primary and secondary cooling systems was satisfactory. The PCA was used in training programs and was operated on two occasions when the University of Kentucky students actively participated in training laboratories.

  12. Multi-Channel, Constant-Current Power Source for Aircraft Applications

    DTIC Science & Technology

    2017-03-01

    Special considerations impacting this design were minimizing volume, maintaining system power quality, and providing electrical fault protection...applications. Electrical loads, such as lighting, de-icing heaters, and actuators may be operated from this compact power conversion unit. Because of the...nature of aircraft systems, two of the most important design considerations are the maintenance of electrical power quality and minimization of weight

  13. Applications and research on nano power electronics: an adventure beyond quantum electronics

    NASA Astrophysics Data System (ADS)

    Chakraborty, Arindam; Emadi, Ali

    2005-06-01

    This paper is a roadmap to the exhaustive role of the newly emerging field of nanotechnology in various application and research areas. Some of the today's important topics are plasma, dielectric layer semiconductor, and carbon nanoparticle based technologies. Carbon nanotubes are very useful for the purpose of fabricating nano opto power devices. The basic concept behind tunneling of electrons has been utilized to define another scope of this technology, and thus came many quantum scale tunneling devices and elements. Fabrication of crystal semiconductors of high quality along with oxides of nano aspect would give rise to superior device performance and find applications such as LEDs, LASER, VLSI technology and also in highly efficient solar cells. Many nano-research based organizations are fully devoted to develop nano power cells, which would give birth to new battery cells, tunneling devises, with high power quality, longer lives, and higher activation rates. Different electronics industries as well as the military organizations would be largely benefited due to this major component and system design ideas of 'Smart Power' technologies. The contribution of nano scale power electronics would be realized in various fields like switching devices, electromechanical systems and quantum science. Such a sophisticated technology will have great impact on the modernization of robotics; space systems, automotive systems and many other fields. The highly emerging field of nanomedicine according to specialists would bring a dramatic revolution in the present century. However nanomedicine is nothing but an integration of biology, medicine and technology. Thermoelectric materials as been referred earlier also are used in case of implantable medical equipments for generation of electric power sufficient for those equipments.

  14. A Review Analysis of Inverter Topologies for Solar PV Applications Focused on Power Quality

    NASA Astrophysics Data System (ADS)

    Faruqui, Saad Nazif Ahamad; Anwer, Naqui

    2017-10-01

    This research article gives widespread review of non-isolated topologies for solar photovoltaic equipments. To relate with available elucidations of the said studied topological arrangement, some conditions have been imposed. The benchmark is based on harmonic distortion as well as power quality issues. Some of the selected solution have been designed and simulated for power quality issues. The best one has been discussed in the paper.

  15. HOS network-based classification of power quality events via regression algorithms

    NASA Astrophysics Data System (ADS)

    Palomares Salas, José Carlos; González de la Rosa, Juan José; Sierra Fernández, José María; Pérez, Agustín Agüera

    2015-12-01

    This work compares seven regression algorithms implemented in artificial neural networks (ANNs) supported by 14 power-quality features, which are based in higher-order statistics. Combining time and frequency domain estimators to deal with non-stationary measurement sequences, the final goal of the system is the implementation in the future smart grid to guarantee compatibility between all equipment connected. The principal results are based in spectral kurtosis measurements, which easily adapt to the impulsive nature of the power quality events. These results verify that the proposed technique is capable of offering interesting results for power quality (PQ) disturbance classification. The best results are obtained using radial basis networks, generalized regression, and multilayer perceptron, mainly due to the non-linear nature of data.

  16. Effect of repetitive transcranial magnetic stimulation on reducing spasticity in patients suffering from HTLV-1-associated myelopathy.

    PubMed

    Amiri, Mostafa; Nafissi, Shahriar; Jamal-Omidi, Shirin; Amiri, Motahareh; Fatehi, Farzad

    2014-12-01

    Human T-lymphotropic virus type 1 has been implicated in human T-lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Regarding its endemicity in Iran and the role of repetitive transcranial magnetic stimulation in reducing spasticity, we decided to evaluate the efficacy of repetitive transcranial magnetic stimulation in reducing spasticity (as primary outcome) and pain, muscle power, and quality of life (as secondary outcomes) in patients suffering from HAM/TSP. In this pretest-posttest study, nine definite patients with HAM/TSP (according to WHO guidelines) were recruited. All patients underwent five consecutive daily sessions of active repetitive transcranial magnetic stimulation (each session consisting of 20 trains of 10 pulses at 5 Hz and an intensity of 90% of resting motor threshold for the biceps brachii muscle). Main outcome measures including spasticity (by modified Ashworth scale), pain (by visual analog scale), muscle power, and quality of life (by SF 36) were measured before the study and days 5, 7, 30 after the termination of the sessions. Seven (77.8%) females and 2 (22.2%) males were recruited with the mean age of 52 ± 12.67 years, and the mean duration of the disease was 5 ± 3.94. Comparison of the repeated measures showed a statistically significant decrease in pain and spasticity in lower limbs. The decrement in spasticity was persistent even 30 days after the intervention; however, the pain reduction was seen only 5 days after the procedure. No change in quality of life, and muscle power was detected. It seems that repetitive transcranial magnetic stimulation could decrease spasticity and pain in patients with HAM/TSP, and this effect could persistently continue by 1 month, but it did not influence patients' muscle power and quality of life, and it could be used as an adjuvant therapy in patients suffering from human T-lymphotropic virus type 1-associated HAM/TSP.

  17. Influence of fundamental mode fill factor on disk laser output power and laser beam quality

    NASA Astrophysics Data System (ADS)

    Cheng, Zhiyong; Yang, Zhuo; Shao, Xichun; Li, Wei; Zhu, Mengzhen

    2017-11-01

    An three-dimensional numerical model based on finite element method and Fox-Li method with angular spectrum diffraction theoy is developed to calculate the output power and power density distribution of Yb:YAG disk laser. We invest the influence of fundamental mode fill factor(the ratio of fundamental mode size and pump spot size) on the output power and laser beam quality. Due to aspherical aberration and soft aperture effect in laser disk, high beam quality can be achieve with relative lower efficiency. The highest output power of fundamental laser mode is influenced by the fundamental mode fill factor. Besides we find that optimal mode fill factor increase with pump spot size.

  18. Human motion energy harvesting using a piezoelectric MFC patch.

    PubMed

    Bassani, Giulia; Filippeschi, Alessandro; Ruffaldi, Emanuele

    2015-01-01

    The improvements in efficiency of electronic components and miniaturization is quickly pushing wearable devices. Kinetic human energy harvesting is a way to power these components reducing the need of batteries replacement since walking or running is how humans already expend much of their daily energy. This work explores the case of kinetic energy from bending of a piezoelectric patch. For assessing the quality of the system, a testing setup has been designed and controlled by means of knee joint recordings obtained from a large motion dataset. The promising result of the chosen patch is an output power of 2.6μW associated to a run activity.

  19. Low Power Transmitter for Wireless Capsule Endoscope

    NASA Astrophysics Data System (ADS)

    Lioe, D. X.; Shafie, S.; Ramiah, H.; Sulaiman, N.; Halin, I. A.

    2013-04-01

    This paper presents the transmitter circuit designed for the application of wireless capsule endoscope to overcome the limitation of conventional endoscope. The design is performed using CMOS 0.13 μm technology. The transmitter is designed to operate at centre frequency of 433.92 MHz, which is one of the ISM band. Active mixer and ring oscillator made up the transmitter and it consumes 1.57 mA of current using a supply voltage of 1.2 V, brings the dc power consumption of the transmitter to be 1.88 mW. Data rate of 3.5 Mbps ensure it can transmit high quality medical imaging.

  20. Optimization of light quality from color mixing light-emitting diode systems for general lighting

    NASA Astrophysics Data System (ADS)

    Thorseth, Anders

    2012-03-01

    Given the problem of metamerisms inherent in color mixing in light-emitting diode (LED) systems with more than three distinct colors, a method for optimizing the spectral output of multicolor LED system with regards to standardized light quality parameters has been developed. The composite spectral power distribution from the LEDs are simulated using spectral radiometric measurements of single commercially available LEDs for varying input power, to account for the efficiency droop and other non-linear effects in electrical power vs. light output. The method uses electrical input powers as input parameters in a randomized steepest decent optimization. The resulting spectral power distributions are evaluated with regard to the light quality using the standard characteristics: CIE color rendering index, correlated color temperature and chromaticity distance. The results indicate Pareto optimal boundaries for each system, mapping the capabilities of the simulated lighting systems with regard to the light quality characteristics.

  1. Performance Analysis of Isolated Hybrid Power Plant Model with Dynamic Load Conditions - Morning, Noon and Afternoon Transitions

    NASA Astrophysics Data System (ADS)

    Irawati, Rina

    2018-02-01

    Diesel Generator with Photovoltaic Hybrid Power Plant is one of the solutions for supply electric demand to isolated area. The energy sources that can be used for hybrid system are such as photovoltaic, wind turbine, and biomass or biogas, because these sources are almost available in every isolated area. This research used a model of hybrid system from diesel generator and 1.28 kWp photovoltaic power plant. The reliability and some of power quality of this system tested by 1300VA house hold daily load characteristic effectively 24 hour. Power quality and some electricity parameters during transition mode for each resource will be analyzed. Furthermore the power quality analyze will be conducted and evaluated base on Electrical Engineers' Association (EEA).

  2. Emissions Inventory of Anthropogenic PM2.5 and PM10 in Mega city, Delhi, India for Air Quality Forecasting during CWG- 2010

    NASA Astrophysics Data System (ADS)

    Sahu, S.; Beig, G.; Schultz, M.; Parkhi, N.; Stein, O.

    2012-04-01

    The mega city of Delhi is the second largest urban agglomeration in India with 16.7 mio. inhabitants. Delhi has the highest per capita power consumption of electricity in India and the demand has risen by more than 50% during the last decade. Emissions from commercial, power, domestic and industrial sectors have strongly increased causing more and more environmental problems due to air pollution and its adverse impacts on human health. Particulate matter (PM) of size less than 2.5-micron (PM2.5) and 10 micron (PM10) have emerged as primary pollutants of concern due to their adverse impact on human health. As part of the System of Air quality Forecasting and Research (SAFAR) project developed for air quality forecasting during the Commonwealth Games (CWG) - 2010, a high resolution Emission Inventory (EI) of PM10 and PM2.5 has been developed for the metropolitan city Delhi for the year 2010. The comprehensive inventory involves detailed activity data and has been developed for a domain of 70km×65km with a 1.67km×1.67km resolution covering Delhi and its surrounding region (i.e. National Capital Region (NCR)). In creating this inventory, Geographical Information System (GIS) based techniques were used for the first time in India. The major sectors considered are, transport, thermal power plants, industries, residential and commercial cooking along with windblown road dust which is found to play a major role for the megacity environment. Extensive surveys were conducted among the Delhi slum dwellers (Jhuggi) in order to obtain more robust estimates for the activity data related to domestic cooking and heating. Total emissions of PM10 and PM2.5 including wind blown dust over the study area are found to be 236 Gg/yr and 94 Gg/yr respectively. About half of the PM10 emissions stem from windblown road dust. The new emission inventory has been used for regional air quality forecasts in the Delhi region during the Commonwealth games (SAFAR project), and they will soon be tested in simulations of the global atmospheric composition in the framework of the European MACC project which provided the chemical boundary conditions to the regional air quality forecasts in 2010.

  3. Progress in Materials and Component Development for Advanced Lithium-ion Cells for NASA's Exploration Missions

    NASA Technical Reports Server (NTRS)

    Reid, Concha, M.; Reid, Concha M.

    2011-01-01

    Vehicles and stand-alone power systems that enable the next generation of human missions to the Moon will require energy storage systems that are safer, lighter, and more compact than current state-of-the- art (SOA) aerospace quality lithium-ion (Li-ion) batteries. NASA is developing advanced Li-ion cells to enable or enhance the power systems for the Altair Lunar Lander, Extravehicular Activities spacesuit, and rovers and portable utility pallets for Lunar Surface Systems. Advanced, high-performing materials are required to provide component-level performance that can offer the required gains at the integrated cell level. Although there is still a significant amount of work yet to be done, the present state of development activities has resulted in the synthesis of promising materials that approach the ultimate performance goals. This report on interim progress of the development efforts will elaborate on the challenges of the development activities, proposed strategies to overcome technical issues, and present performance of materials and cell components.

  4. 10 CFR Appendix B to Part 50 - Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Quality Assurance Criteria for Nuclear Power Plants and... LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Pt. 50, App. B Appendix B to Part 50—Quality Assurance... report a description of the quality assurance program to be applied to the design, fabrication...

  5. Effects of vitamin D receptor gene polymorphisms on low-resistance training using exercise machines: the 'Power Rehabilitation' program.

    PubMed

    Murakami, Shin-Ichiro; Otsuki, Takemi; Maeda, Megumi; Miura, Yoshie; Morii, Seiko; Kiyokane, Kenji; Hayakawa, Shin-Ichi; Maeda, Atsushi; Imakawa, Takayo; Harada, Shunpei; Handa, Torataro; Nishimura, Yasumitsu; Murakami, Shuko; Kumagai, Naoko; Hayashi, Hiroaki; Chen, Ying; Suemori, Shin-Ichiro; Fukushima, Yumiko; Nishida, Seikoh; Fukushima, Keisuke

    2009-01-01

    The enhancement and promotion of health is necessary to maintain the quality of life (QOL) of the aged population in developed nations such as Japan where the number of elderly has been increasing rapidly. For this purpose, low-resistance training using exercise machines ('Power Rehabilitation') has been established as a rehabilitation program. To investigate the individual factors which influence the effects of 'Power Rehabilitation', single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene and the ciliary neurotrophic factor (CNTF) gene were analyzed, and the relationship between SNP patterns and the effects of 'Power Rehabilitation' was evaluated. 'Power Rehabilitation' had an effect on the physiological functions involved in the activities of daily life (ADL) rather than muscle strength and size. In addition, certain SNP patterns showed better improvement of parameters associated with the effects of 'Power Rehabilitation' as analyzed by comparison between SNP patterns and factor analysis. Large scale analyses are required to ensure this tendency and to discover individual factors which may help to promote the health and QOL of the aged population.

  6. Coptidis rhizoma and its main bioactive components: recent advances in chemical investigation, quality evaluation and pharmacological activity.

    PubMed

    Meng, Fan-Cheng; Wu, Zheng-Feng; Yin, Zhi-Qi; Lin, Li-Gen; Wang, Ruibing; Zhang, Qing-Wen

    2018-01-01

    Coptidis rhizoma (CR) is the dried rhizome of Coptis chinensis Franch., C. deltoidea C. Y. Cheng et Hsiao or C. teeta Wall. (Ranunculaceae) and is commonly used in Traditional Chinese Medicine for the treatment of various diseases including bacillary dysentery, typhoid, tuberculosis, epidemic cerebrospinal meningitis, empyrosis, pertussis, and other illnesses. A literature survey was conducted via SciFinder, ScieneDirect, PubMed, Springer, and Wiley databases. A total of 139 selected references were classified on the basis of their research scopes, including chemical investigation, quality evaluation and pharmacological studies. Many types of secondary metabolites including alkaloids, lignans, phenylpropanoids, flavonoids, phenolic compounds, saccharides, and steroids have been isolated from CR. Among them, protoberberine-type alkaloids, such as berberine, palmatine, coptisine, epiberberine, jatrorrhizine, columamine, are the main components of CR. Quantitative determination of these alkaloids is a very important aspect in the quality evaluation of CR. In recent years, with the advances in isolation and detection technologies, many new instruments and methods have been developed for the quantitative and qualitative analysis of the main alkaloids from CR. The quality control of CR has provided safety for pharmacological applications. These quality evaluation methods are also frequently employed to screen the active components from CR. Various investigations have shown that CR and its main alkaloids exhibited many powerful pharmacological effects including anti-inflammatory, anti-cancer, anti-diabetic, neuroprotective, cardioprotective, hypoglycemic, anti-Alzheimer and hepatoprotective activities. This review summarizes the recent phytochemical investigations, quality evaluation methods, the biological studies focusing on CR as well as its main alkaloids.

  7. A periodicity of approximately 1 hour in X-ray emission from the active galaxy RE J1034+396.

    PubMed

    Gierliński, Marek; Middleton, Matthew; Ward, Martin; Done, Chris

    2008-09-18

    Active galactic nuclei and quasars are thought to be scaled-up versions of Galactic black hole binaries, powered by accretion onto supermassive black holes with masses of 10(6)-10(9) M[symbol: see text], as opposed to the approximately 10 M [symbol: see text] in binaries (here M [symbol: see text] is the solar mass). One example of the similarities between these two types of systems is the characteristic rapid X-ray variability seen from the accretion flow. The power spectrum of this variability in black hole binaries consists of a broad noise with multiple quasi-periodic oscillations superimposed on it. Although the broad noise component has been observed in many active galactic nuclei, there have hitherto been no significant detections of quasi-periodic oscillations. Here we report the discovery of an approximately 1-hour X-ray periodicity in a bright active galaxy, RE J1034+396. The signal is highly statistically significant (at the 5.6 sigma level) and very coherent, with quality factor Q > 16. The X-ray modulation arises from the direct vicinity of the black hole.

  8. An Improved Power Quality BIBRED Converter-Based VSI-Fed BLDC Motor Drive

    NASA Astrophysics Data System (ADS)

    Singh, Bhim; Bist, Vashist

    2014-01-01

    This paper presents an IHQRR (integrated high-quality rectifier regulator) BIBRED (boost integrated buck rectifier energy storage DC-DC) converter-based VSI (voltage source inverter)-fed BLDC (brushless DC) motor drive. The speed control of BLDC motor is achieved by controlling the DC link voltage of the VSI using a single voltage sensor. This allows VSI to operate in fundamental frequency switching mode for electronic commutation of BLDC motor which reduces the switching losses due to high-frequency switching used in conventional approach of PWM (pulse width modulation)-based VSI-fed BLDC motor drive. A BIBRED converter is operated in a dual-DCM (discontinuous conduction mode) thus using a voltage follower approach for PFC (power factor correction) and DC link voltage control. The performance of the proposed drive is evaluated for improved power quality over a wide range of speed control and supply voltage variation for demonstrating the behavior of proposed drive. The power quality indices thus obtained are within the recommended limits by international PQ (power quality) standards such as IEC 61000-3-2.

  9. Fuel cells provide a revenue-generating solution to power quality problems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    King, J.M. Jr.

    Electric power quality and reliability are becoming increasingly important as computers and microprocessors assume a larger role in commercial, health care and industrial buildings and processes. At the same time, constraints on transmission and distribution of power from central stations are making local areas vulnerable to low voltage, load addition limitations, power quality and power reliability problems. Many customers currently utilize some form of premium power in the form of standby generators and/or UPS systems. These include customers where continuous power is required because of health and safety or security reasons (hospitals, nursing homes, places of public assembly, air trafficmore » control, military installations, telecommunications, etc.) These also include customers with industrial or commercial processes which can`t tolerance an interruption of power because of product loss or equipment damage. The paper discusses the use of the PC25 fuel cell power plant for backup and parallel power supplies for critical industrial applications. Several PC25 installations are described: the use of propane in a PC25; the use by rural cooperatives; and a demonstration of PC25 technology using landfill gas.« less

  10. Quantitative structure-activity relationship models that stand the test of time.

    PubMed

    Davis, Andrew M; Wood, David J

    2013-04-01

    The pharmaceutical industry is in a period of intense change. While this has many drivers, attrition through the development process continues to be an important pressure. The emerging definitions of "compound quality" that are based on retrospective analyses of developmental attrition have highlighted a new direction for medicinal chemistry and the paradigm of "quality at the point of design". The time has come for retrospective analyses to catalyze prospective action. Quality at the point of design places pressure on the quality of our predictive models. Empirical QSAR models when built with care provide true predictive control, but their accuracy and precision can be improved. Here we describe AstraZeneca's experience of automation in QSAR model building and validation, and how an informatics system can provide a step-change in predictive power to project design teams, if they choose to use it.

  11. Design and implementation of artistic gymnastics training guidance system

    NASA Astrophysics Data System (ADS)

    Cai, Limin; Luo, Lin

    2017-04-01

    Artistic gymnastics (AG) has developed into a favorite sports activity among many university students; recent years saw not only the increase of AG learners, but also the emergence of more and more problems in the training. Based on surveys in different forms, students' physical quality and their performance in the AG training were analyzed and summarized; and with the aid of the computer technology, Artistic Gymnastics Training Guidance System was designed and implemented to meet the students' needs for personalized training schemes and improve AG teaching quality. The System can provide convenient ways for scientific training in a targeted and oriented manner on the basis of the differences in physical quality. Also, it can provide teachers with detailed data about the students' physical quality and their AG training; through the visualization of valuable statistical data, it is able to provide a powerful basis for decision makers of teaching departments and thus facilitate the perfection of AG teaching methods.

  12. 18 CFR 801.7 - Water quality.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Water quality. 801.7 Section 801.7 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN COMMISSION GENERAL POLICIES § 801.7 Water quality. (a) The signatory States have the primary responsibility in the basin for...

  13. Knowledge, Power and Meanings Shaping Quality Assurance in Higher Education: A Systemic Critique

    ERIC Educational Resources Information Center

    Houston, Don; Paewai, Shelley

    2013-01-01

    Internationally, quality assurance schemes persist despite long-standing dissatisfaction and critique of their impact and outcomes. Adopting a critical systems perspective, the article explores the relationships between the knowledge, power and meanings that stakeholder groups bring to the design and implementation of quality assurance systems.…

  14. 18 CFR 801.7 - Water quality.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Water quality. 801.7 Section 801.7 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN COMMISSION GENERAL POLICIES § 801.7 Water quality. (a) The signatory States have the primary responsibility in the basin for...

  15. 18 CFR 801.7 - Water quality.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Water quality. 801.7 Section 801.7 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN COMMISSION GENERAL POLICIES § 801.7 Water quality. (a) The signatory States have the primary responsibility in the basin for...

  16. 18 CFR 801.7 - Water quality.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Water quality. 801.7 Section 801.7 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN COMMISSION GENERAL POLICIES § 801.7 Water quality. (a) The signatory States have the primary responsibility in the basin for...

  17. Control of Solar Power Plants Connected Grid with Simple Calculation Method on Residential Homes

    NASA Astrophysics Data System (ADS)

    Kananda, Kiki; Nazir, Refdinal

    2017-12-01

    One of the most compatible renewable energy in all regions to apply is solar energy. Solar power plants can be built connected to existing or stand-alone power grids. In assisting the residential electricity in which there is a power grid, then a small scale solar energy power plants is very appropriate. However, the general constraint of solar energy power plants is still low in terms of efficiency. Therefore, this study will explain how to control the power of solar power plants more optimally, which is expected to reactive power to zero to raise efficiency. This is a continuation of previous research using Newton Rapshon control method. In this study we introduce a simple method by using ordinary mathematical calculations of solar-related equations. In this model, 10 PV modules type of ND T060M1 with a 60 Wp capacity are used. The calculations performed using MATLAB Simulink provide excellent value. For PCC voltage values obtained a stable quantity of approximately 220 V. At a maximum irradiation condition of 1000 W / m2, the reactive power value of Q solar generating system maximum 20.48 Var and maximum active power of 417.5 W. In the condition of lower irradiation, value of reactive power Q almost close to zero 0.77Var. This simple mathematical method can provide excellent quality control power values.

  18. Community air monitoring and the Village Green Project ...

    EPA Pesticide Factsheets

    Cost and logistics are practical issues that have historically constrained the number of locations where long-term, active air pollution measurement is possible. In addition, traditional air monitoring approaches are generally conducted by technical experts with limited engagement with community members. EPA’s Village Green Project (VGP) is a prototype technology designed to add value to a community environment – VGP is a park bench equipped with air and meteorological instruments that measure ozone, fine particles, wind, temperature, and humidity at a one-minute time resolution, with the open-source Arduino microprocessor operating as the system controller. The data are streamed wirelessly to a database, passed through automatic diagnostic quality checks, and then made publically available on an engaging website. The station was designed to minimize power use; it consumes an estimated 15W and operates entirely on solar power, is engineered to run for several days with minimal solar radiation, and is capable of automatically shutting down components of the system to conserve power and restarting when power availability increases. Situated outside a public library in Durham, North Carolina, VGP has also been a gathering location for air quality experts to engage with community members. During the time span of June, 2013 through January, 2014, the station collected about 3500 hours of ozone and PM2.5 data, with over 90% up-time operating only on solar po

  19. An ultra-low power (ULP) bandage-type ECG sensor for efficient cardiac disease management.

    PubMed

    Shin, Kunsoo; Park, G G; Kim, J P; Lee, T H; Ko, B H; Kim, Y H

    2013-01-01

    This paper proposed an ultra-low power bandage-type ECG sensor (the size: 76 × 34 × 3 (mm(3)) and the power consumption: 1 mW) which allows for a continuous and real-time monitoring of a user's ECG signals over 24h during daily activities. For its compact size and lower power consumption, we designed the analog front-end, the SRP (Samsung Reconfigurable Processor) based DSP of 30 uW/MHz, and the ULP wireless RF of 1 nJ/bit. Also, to tackle motion artifacts(MA), a MA monitoring technique based on the HCP (Half-cell Potential) is proposed which resulted in the high correlation between the MA and the HCP, the correlation coefficient of 0.75 ± 0.18. To assess its feasibility and validity as a wearable health monitor, we performed the comparison of two ECG signals recorded form it and a conventional Holter device. As a result, the performance of the former is a little lower as compared with the latter, although showing no statistical significant difference (the quality of the signal: 94.3% vs 99.4%; the accuracy of arrhythmia detection: 93.7% vs 98.7%). With those results, it has been confirmed that it can be used as a wearable health monitor due to its comfortability, its long operation lifetime and the good quality of the measured ECG signal.

  20. Research on improvement of power quality of Micro - grid based on SVG pulse load

    NASA Astrophysics Data System (ADS)

    Lv, Chuang; Xie, Pu

    2017-05-01

    Pulse load will make the micro-grid public bus power to produce a high peak pulse due to its cyclical pulsation characteristics,, and make the micro-grid voltage fluctuations, frequency fluctuations, voltage and current distortion, power factor reduction and other adverse effects. In order to suppress the adverse effects of the pulse load on the microgrid and improve the power quality of the microgrid, this paper established the SVG simulation model in Matlab / Simulink environment, the superiority of SVG is verified by comparing the improvement of power quality before and after adding the SVG to microgrid system. The results show that the SVG model can suppress the adverse effects effectively of the pulse load on the microgrid, which is of great value and significance to the reactive power compensation and harmonic suppression of the microgrid.

  1. Development of high-average-power DPSSL with high beam quality

    NASA Astrophysics Data System (ADS)

    Nakai, Sadao; Kanabe, Tadashi; Kawashima, Toshiyuki; Yamanaka, Masanobu; Izawa, Yasukazu; Nakatuka, Masahiro; Kandasamy, Ranganathan; Kan, Hirofumi; Hiruma, Teruo; Niino, Masayuki

    2000-08-01

    The recent progress of high power diode laser is opening new fields of laser and its application. We are developing high average power diode pumped solid state laser DPSSL for laser fusion power plant, for space propulsion and for various applications in industry. The common features or requirements of our High Average-power Laser for Nuclear-fusion Application (HALNA) are large pulse energy with relatively low repetition of few tens Hz, good beam quality of order of diffraction limit and high efficiency more than 10%. We constructed HALNA 10 (10J X 10 Hz) and tested the performance to clarify the scalability to higher power system. We have obtained in a preliminary experiment a 8.5 J output energy at 0.5 Hz with beam quality of 2 times diffraction limited far-field pattern.

  2. Computed lateral rate and acceleration power spectral response of conventional and STOL airplanes to atmospheric turbulence

    NASA Technical Reports Server (NTRS)

    Lichtenstein, J. H.

    1975-01-01

    Power-spectral-density calculations were made of the lateral responses to atmospheric turbulence for several conventional and short take-off and landing (STOL) airplanes. The turbulence was modeled as three orthogonal velocity components, which were uncorrelated, and each was represented with a one-dimensional power spectrum. Power spectral densities were computed for displacements, rates, and accelerations in roll, yaw, and sideslip. In addition, the power spectral density of the transverse acceleration was computed. Evaluation of ride quality based on a specific ride quality criterion was also made. The results show that the STOL airplanes generally had larger values for the rate and acceleration power spectra (and, consequently, larger corresponding root-mean-square values) than the conventional airplanes. The ride quality criterion gave poorer ratings to the STOL airplanes than to the conventional airplanes.

  3. Comparison of nutritional qualities and antioxidant properties of ready-to-eat fruit-enriched corn based breakfast cereals.

    PubMed

    Bhavya, S N; Prakash, J

    2012-12-01

    The study aimed to analyse the nutritional quality, antioxidant components and activity of three varieties of corn based ready-to- eat (RTE) breakfast cereals (BFC) enriched with strawberry, banana and mango. Fruit-enriched corn based breakfast cereals manufactured in India were purchased and ground to obtain homogeneous samples for analysis. The contents of moisture, protein, total fat, dietary fibre, iron, phosphorous, calcium, vitamin C, total carotene, thiamine, riboflavin, in vitro digestible protein, bioaccessible calcium and iron, and digestible starch fractions were determined. The antioxidant components namely, polyphenols, flavonoids and antioxidant activity in different extracts were also determined using total antioxidant, free radical scavenging (2,2-diphenyl-1-picrylhydrazyl) and reducing power assays. The protein and dietary fibre contents in all samples ranged between 4.0-4.6 and 6.4-7.6 g/ 100g respectively. Total iron and vitamin C ranged between 10.7-13.3 mg and 33.2-43.6 mg/100g respectively. Cereals with mango had high total carotene in comparison with other samples. In vitro digestible protein of the processed cereals was low, while bioaccessible calcium (50.2-59.5%) and iron (8.5-15.1%) levels were high due to low oxalates and phytic acid contents. The starch profiles of the breakfast cereals showed high rapidly available glucose and starch digestibility index. Fruit-enriched breakfast cereals showed high polyphenol content in methanol extract (48.6-71.3 mg/100g) and high total antioxidant activity in aqueous extracts. Free radical scavenging and reducing power assay showed high activity in 80% methanol extract. Fruit-enriched breakfast cereals have the potential to be a good source of iron, dietary fibre, vitamin C and total carotene. The fruit-enriched cereals also had high bioaccessible iron and antioxidant activity.

  4. Mobility Device Quality Affects Participation Outcomes for People With Disabilities: A Structural Equation Modeling Analysis.

    PubMed

    Magasi, Susan; Wong, Alex; Miskovic, Ana; Tulsky, David; Heinemann, Allen W

    2018-01-01

    To test the effect that indicators of mobility device quality have on participation outcomes in community-dwelling adults with spinal cord injury, traumatic brain injury, and stroke by using structural equation modeling. Survey, cross-sectional study, and model testing. Clinical research space at 2 academic medical centers and 1 free-standing rehabilitation hospital. Community-dwelling adults (N=250; mean age, 48±14.3y) with spinal cord injury, traumatic brain injury, and stroke. Not applicable. The Mobility Device Impact Scale, Patient-Reported Outcomes Measurement Information System Social Function (version 2.0) scale, including Ability to Participate in Social Roles and Activities and Satisfaction with Social Roles and Activities, and the 2 Community Participation Indicators' enfranchisement scales. Details about device quality (reparability, reliability, ease of maintenance) and device type were also collected. Respondents used ambulation aids (30%), manual (34%), and power wheelchairs (30%). Indicators of device quality had a moderating effect on participation outcomes, with 3 device quality variables (repairability, ease of maintenance, device reliability) accounting for 20% of the variance in participation. Wheelchair users reported lower participation enfranchisement than did ambulation aid users. Mobility device quality plays an important role in participation outcomes. It is critical that people have access to mobility devices and that these devices be reliable. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Power and the Association with Relationship Quality in South African Couples: Implications for HIV/AIDS Interventions

    PubMed Central

    Conroy, Amy A.; McGrath, Nuala; van Rooyen, Heidi; Hosegood, Victoria; Johnson, Mallory O.; Fritz, Katherine; Marr, Alexander; Ngubane, Thulani; Darbes, Lynae A.

    2016-01-01

    Introduction Power imbalances within sexual relationships have significant implications for HIV prevention in sub-Saharan Africa. Little is known about how power influences the quality of a relationship, which could be an important pathway leading to healthy behavior around HIV/AIDS. Methods This paper uses data from 448 heterosexual couples (896 individuals) in rural KwaZulu-Natal, South Africa who completed baseline surveys from 2012–2014 as part of a couples-based HIV intervention trial. Using an actor-partner interdependence perspective, we assessed: (1) how both partners’ perceptions of power influences their own (i.e., actor effect) and their partner’s reports of relationship quality (i.e., partner effect); and (2) whether these associations differed by gender. We examined three constructs related to power (female power, male equitable gender norms, and shared power) and four domains of relationship quality (intimacy, trust, mutually constructive communication, and conflict). Results For actor effects, shared power was strongly and consistently associated with higher relationship quality across all four domains. The effect of shared power on trust, mutually constructive communication, and conflict were stronger for men than women. The findings for female power and male equitable gender norms were more mixed. Female power was positively associated with women’s reports of trust and mutually constructive communication, but negatively associated with intimacy. Male equitable gender norms were positively associated with men’s reports of mutually constructive communication. For partner effects, male equitable gender norms were positively associated with women’s reports of intimacy and negatively associated with women’s reports of conflict. Conclusions Research and health interventions aiming to improving HIV-related behaviors should consider sources of shared power within couples and potential leverage points for empowerment at the couple level. Efforts solely focused on empowering women should also take the dyadic environment and men’s perspectives into account to ensure positive relationship outcomes. PMID:26859436

  6. Power and the association with relationship quality in South African couples: Implications for HIV/AIDS interventions.

    PubMed

    Conroy, Amy A; McGrath, Nuala; van Rooyen, Heidi; Hosegood, Victoria; Johnson, Mallory O; Fritz, Katherine; Marr, Alexander; Ngubane, Thulani; Darbes, Lynae A

    2016-03-01

    Power imbalances within sexual relationships have significant implications for HIV prevention in sub-Saharan Africa. Little is known about how power influences the quality of a relationship, which could be an important pathway leading to healthy behavior around HIV/AIDS. This paper uses data from 448 heterosexual couples (896 individuals) in rural KwaZulu-Natal, South Africa who completed baseline surveys from 2012 to 2014 as part of a couples-based HIV intervention trial. Using an actor-partner interdependence perspective, we assessed: (1) how both partners' perceptions of power influences their own (i.e., actor effect) and their partner's reports of relationship quality (i.e., partner effect); and (2) whether these associations differed by gender. We examined three constructs related to power (female power, male equitable gender norms, and shared power) and four domains of relationship quality (intimacy, trust, mutually constructive communication, and conflict). For actor effects, shared power was strongly and consistently associated with higher relationship quality across all four domains. The effect of shared power on trust, mutually constructive communication, and conflict were stronger for men than women. The findings for female power and male equitable gender norms were more mixed. Female power was positively associated with women's reports of trust and mutually constructive communication, but negatively associated with intimacy. Male equitable gender norms were positively associated with men's reports of mutually constructive communication. For partner effects, male equitable gender norms were positively associated with women's reports of intimacy and negatively associated with women's reports of conflict. Research and health interventions aiming to improving HIV-related behaviors should consider sources of shared power within couples and potential leverage points for empowerment at the couple level. Efforts solely focused on empowering women should also take the dyadic environment and men's perspectives into account to ensure positive relationship outcomes. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Fuels research studies at NASA Lewis

    NASA Technical Reports Server (NTRS)

    Antoine, A. C.

    1982-01-01

    Fuels research studies carried out in a variety of areas related to aviation propulsion, ground transportation, and stationary power generation systems are discussed. The major efforts are directed to studies on fuels for jet aircraft. These studies involve fuels preparation, fuels analysis, and fuel quality evaluations. The scope and direction of research activities in these areas is discussed, descriptions of Lewis capabilities and facilities given, and results of recent research efforts reported.

  8. The N-Pact Factor: Evaluating the Quality of Empirical Journals with Respect to Sample Size and Statistical Power

    PubMed Central

    Fraley, R. Chris; Vazire, Simine

    2014-01-01

    The authors evaluate the quality of research reported in major journals in social-personality psychology by ranking those journals with respect to their N-pact Factors (NF)—the statistical power of the empirical studies they publish to detect typical effect sizes. Power is a particularly important attribute for evaluating research quality because, relative to studies that have low power, studies that have high power are more likely to (a) to provide accurate estimates of effects, (b) to produce literatures with low false positive rates, and (c) to lead to replicable findings. The authors show that the average sample size in social-personality research is 104 and that the power to detect the typical effect size in the field is approximately 50%. Moreover, they show that there is considerable variation among journals in sample sizes and power of the studies they publish, with some journals consistently publishing higher power studies than others. The authors hope that these rankings will be of use to authors who are choosing where to submit their best work, provide hiring and promotion committees with a superior way of quantifying journal quality, and encourage competition among journals to improve their NF rankings. PMID:25296159

  9. Slip-Sliding-Away: A Review of the Literature on the Constraining Qualities of PowerPoint

    ERIC Educational Resources Information Center

    Kernbach, Sebastian; Bresciani, Sabrina; Eppler, Martin J.

    2015-01-01

    PowerPoint is a dominant communication tool in business and education. It allows for creating professional-looking presentations easily, but without understanding its constraining qualities it can be used inappropriately. Therefore we conducted a systematic literature review structuring the literature on PowerPoint in three chronological phases…

  10. Muscle power is an independent determinant of pain and quality of life in knee osteoarthritis

    USDA-ARS?s Scientific Manuscript database

    OBJECTIVE: This study examined the relationships between leg muscle strength, power, and perceived disease severity in subjects with knee osteoarthritis (OA) in order to determine whether dynamic leg extensor muscle power would be associated with pain and quality of life in knee OA. METHODS: Baseli...

  11. Finite volume analysis of temperature effects induced by active MRI implants with cylindrical symmetry: 1. Properly working devices

    PubMed Central

    Busch, Martin HJ; Vollmann, Wolfgang; Schnorr, Jörg; Grönemeyer, Dietrich HW

    2005-01-01

    Background Active Magnetic Resonance Imaging implants are constructed as resonators tuned to the Larmor frequency of a magnetic resonance system with a specific field strength. The resonating circuit may be embedded into or added to the normal metallic implant structure. The resonators build inductively coupled wireless transmit and receive coils and can amplify the signal, normally decreased by eddy currents, inside metallic structures without affecting the rest of the spin ensemble. During magnetic resonance imaging the resonators generate heat, which is additional to the usual one described by the specific absorption rate. This induces temperature increases of the tissue around the circuit paths and inside the lumen of an active implant and may negatively influence patient safety. Methods This investigation provides an overview of the supplementary power absorbed by active implants with a cylindrical geometry, corresponding to vessel implants such as stents, stent grafts or vena cava filters. The knowledge of the overall absorbed power is used in a finite volume analysis to estimate temperature maps around different implant structures inside homogeneous tissue under worst-case assumptions. The "worst-case scenario" assumes thermal heat conduction without blood perfusion inside the tissue around the implant and mostly without any cooling due to blood flow inside vessels. Results The additional power loss of a resonator is proportional to the volume and the quality factor, as well as the field strength of the MRI system and the specific absorption rate of the applied sequence. For properly working devices the finite volume analysis showed only tolerable heating during MRI investigations in most cases. Only resonators transforming a few hundred mW into heat may reach temperature increases over 5 K. This requires resonators with volumes of several ten cubic centimeters, short inductor circuit paths with only a few 10 cm and a quality factor above ten. Using MR sequences, for which the MRI system manufacturer declares the highest specific absorption rate of 4 W/kg, vascular implants with a realistic construction, size and quality factor do not show temperature increases over a critical value of 5 K. Conclusion The results show dangerous heating for the assumed "worst-case scenario" only for constructions not acceptable for vascular implants. Realistic devices are safe with respect to temperature increases. However, this investigation discusses only properly working devices. Ruptures or partial ruptures of the wires carrying the electric current of the resonance circuits or other defects can set up a power source inside an extremely small volume. The temperature maps around such possible "hot spots" should be analyzed in an additional investigation. PMID:15819973

  12. "Let the drag race begin": the rewards of becoming a queen.

    PubMed

    Hopkins, Steven J

    2004-01-01

    Drawing upon my ethnographic experiences in a drag venue called The Park in Roanoke, Virginia, this article explores the experiences of female impersonators in terms of their early motivations for doing drag, how they create and maintain drag personas and identities, and the obstacles to becoming a queen. Departing from previous researchers that have framed female impersonation as a deviant, stigmatizing, and pathological activity, this research analyzes the significant benefits some drag queens garner by donning women's attire. An experiential understanding of drag reveals that the significant rewards from the activity--contextual power and status, self-affirmation and empowerment--are powerful motivating factors. Instead of being deviant and/or partaking in pathological behavior, female impersonators can be seen as operating on an incentive system where the benefits of doing drag positively enrich the quality of the performer's life in a context where successful queens are held in the highest regard.

  13. Resonantly diode-pumped Er:YAG laser: 1470-nm versus 1530-nm CW pumping case

    NASA Astrophysics Data System (ADS)

    Kudryashov, Igor; Ter-Gabrielyan, Nikolai; Dubinskii, Mark

    2009-05-01

    Growing interest to high power lasers in the eye-safe spectral domain initiated a new wave of activity in developing solid-state lasers based on bulk Er3+-doped materials. The resonant pumping of SSL allows for shifting significant part of thermal load from gain medium itself to the pump diodes, thus greatly reducing gain medium thermal distortions deleterious to SSL power scaling with high beam quality. The two major resonant pumping bands in Er:YAG are centered around 1470 and 1532 nm. Pumping into each of these bands has its pros and contras. The best approach to resonant pumping of Er:YAG active media in terms of pump wavelength is yet to be determined. We report the investigation results of high power diode-pumped Er:YAG laser aimed at direct comparison of resonant pumping at 1470 and 1532 nm. Two sources used for pumping were: 1530-nm 10-diode bar stack (>300 W CW) and 1470-nm 10-diode bar stack (>650 W CW). Both pumps were spectrally narrowed by external volume Bragg gratings. The obtained spectral width of less than 1 nm allowed for 'in-line' pumping of Er3+ in either band. The obtained CW power of over 87 W is, to the best of our knowledge, the record high power reported for resonantly pumped Er:YAG DPSSL at room temperature.

  14. Power Doppler ultrasonography and synovitis: correlating ultrasound imaging with histopathological findings and evaluating the performance of ultrasound equipments.

    PubMed

    Koski, J M; Saarakkala, S; Helle, M; Hakulinen, U; Heikkinen, J O; Hermunen, H

    2006-12-01

    To examine the validity of power Doppler ultrasound imaging to identify synovitis, using histopathology as gold standard, and to assess the performance of ultrasound equipments. 44 synovial sites in small and large joints, bursae and tendon sheaths were depicted with ultrasound. A synovial biopsy was performed on the site depicted and a synovial sample was taken for histopathological evaluation. The performance of three ultrasound devices was tested using flow phantoms. A positive Doppler signal was detected in 29 of 35 (83%) of the patients with active histological inflammation. In eight additional samples, histological examination showed other pathological synovial findings and a Doppler signal was detected in five of them. No significant correlation was found between the amount of Doppler signal and histological synovitis score (r = 0.239, p = NS). The amount of subsynovial infiltration of polymorphonuclear leucocytes and surface fibrin correlated significantly with the amount of power Doppler signal: r = 0.397 (p<0.01) and 0.328 (p<0.05), respectively. The ultrasound devices differed in showing the smallest detectable flow. A negative Doppler signal does not exclude the possibility of synovitis. A positive Doppler signal in the synovium is an indicator of an active synovial inflammation in patients. A Doppler signal does not correlate with the extent of the inflammation and it can also be seen in other synovial reactions. It is important that the quality measurements of ultrasound devices are reported, because the results should be evaluated against the quality of the device used.

  15. Blue 450nm high power semiconductor continuous wave laser bars exceeding rollover output power of 80W

    NASA Astrophysics Data System (ADS)

    König, H.; Lell, A.; Stojetz, B.; Ali, M.; Eichler, C.; Peter, M.; Löffler, A.; Strauss, U.; Baumann, M.; Balck, A.; Malchus, J.; Krause, V.

    2018-02-01

    Industrial material processing like cutting or welding of metals is rather energy efficient using direct diode or diode pumped solid state lasers. However, many applications cannot be addressed by established infrared laser technology due to fundamental material properties of the workpiece: For example materials like copper or gold have too low absorption in the near infrared wavelength range to be processed efficiently by use of existing high power laser systems. The huge interest to enable high power kW systems with more suitable wavelengths in the blue spectral range triggered the German funded research project 'BLAULAS': Therein the feasibility and capability of CW operating high power laser bars based on the GaN material system was investigated by Osram and Laserline. High performance bars were enabled by defeating fundamental challenges like material quality as well as the chip processes, both of which differ significantly from well-known IR laser bars. The research samples were assembled on actively cooled heat sinks with hard solder technology. For the first time an output power of 98W per bar at 60A drive current was achieved. Conversion efficiency as high as 46% at 50W output power was demonstrated.

  16. Wind-Friendly Flexible Ramping Product Design in Multi-Timescale Power System Operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cui, Mingjian; Zhang, Jie; Wu, Hongyu

    With increasing wind power penetration in the electricity grid, system operators are recognizing the need for additional flexibility, and some are implementing new ramping products as a type of ancillary service. However, wind is generally thought of as causing the need for ramping services, not as being a potential source for the service. In this paper, a multi-timescale unit commitment and economic dispatch model is developed to consider the wind power ramping product (WPRP). An optimized swinging door algorithm with dynamic programming is applied to identify and forecast wind power ramps (WPRs). Designed as positive characteristics of WPRs, the WPRPmore » is then integrated into the multi-timescale dispatch model that considers new objective functions, ramping capacity limits, active power limits, and flexible ramping requirements. Numerical simulations on the modified IEEE 118-bus system show the potential effectiveness of WPRP in increasing the economic efficiency of power system operations with high levels of wind power penetration. It is found that WPRP not only reduces the production cost by using less ramping reserves scheduled by conventional generators, but also possibly enhances the reliability of power system operations. Moreover, wind power forecasts play an important role in providing high-quality WPRP service.« less

  17. 75 FR 19948 - Notice of Intent To Prepare an Environmental Impact Statement for the Missouri River Authorized...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-16

    ..., recreation, water quality, and water supply. Public scoping for the MRAPS will begin in late May 2010. Future..., irrigation, navigation, power, recreation, water quality, and water supply. Section 108 of the Energy and... and wildlife, irrigation, power, recreation, water supply, and water quality control; defining the...

  18. Neural Network based Control of SG based Standalone Generating System with Energy Storage for Power Quality Enhancement

    NASA Astrophysics Data System (ADS)

    Nayar, Priya; Singh, Bhim; Mishra, Sukumar

    2017-08-01

    An artificial intelligence based control algorithm is used in solving power quality problems of a diesel engine driven synchronous generator with automatic voltage regulator and governor based standalone system. A voltage source converter integrated with a battery energy storage system is employed to mitigate the power quality problems. An adaptive neural network based signed regressor control algorithm is used for the estimation of the fundamental component of load currents for control of a standalone system with load leveling as an integral feature. The developed model of the system performs accurately under varying load conditions and provides good dynamic response to the step changes in loads. The real time performance is achieved using MATLAB along with simulink/simpower system toolboxes and results adhere to an IEEE-519 standard for power quality enhancement.

  19. Non-REM sleep EEG power distribution in fatigue and sleepiness.

    PubMed

    Neu, Daniel; Mairesse, Olivier; Verbanck, Paul; Linkowski, Paul; Le Bon, Olivier

    2014-04-01

    The aim of this study is to contribute to the sleep-related differentiation between daytime fatigue and sleepiness. 135 subjects presenting with sleep apnea-hypopnea syndrome (SAHS, n=58) or chronic fatigue syndrome (CFS, n=52) with respective sleepiness or fatigue complaints and a control group (n=25) underwent polysomnography and psychometric assessments for fatigue, sleepiness, affective symptoms and perceived sleep quality. Sleep EEG spectral analysis for ultra slow, delta, theta, alpha, sigma and beta power bands was performed on frontal, central and occipital derivations. Patient groups presented with impaired subjective sleep quality and higher affective symptom intensity. CFS patients presented with highest fatigue and SAHS patients with highest sleepiness levels. All groups showed similar total sleep time. Subject groups mainly differed in sleep efficiency, wake after sleep onset, duration of light sleep (N1, N2) and slow wave sleep, as well as in sleep fragmentation and respiratory disturbance. Relative non-REM sleep power spectra distributions suggest a pattern of power exchange in higher frequency bands at the expense of central ultra slow power in CFS patients during all non-REM stages. In SAHS patients, however, we found an opposite pattern at occipital sites during N1 and N2. Slow wave activity presents as a crossroad of fatigue and sleepiness with, however, different spectral power band distributions during non-REM sleep. The homeostatic function of sleep might be compromised in CFS patients and could explain why, in contrast to sleepiness, fatigue does not resolve with sleep in these patients. The present findings thus contribute to the differentiation of both phenomena. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Muscle Power Is an Independent Determinant of Pain and Quality of Life in Knee Osteoarthritis.

    PubMed

    Reid, Kieran F; Price, Lori Lyn; Harvey, William F; Driban, Jeffrey B; Hau, Cynthia; Fielding, Roger A; Wang, Chenchen

    2015-12-01

    This study examined the relationships between leg muscle strength, power, and perceived disease severity in subjects with knee osteoarthritis (OA) in order to determine whether dynamic leg extensor muscle power would be associated with pain and quality of life in knee OA. Baseline data on 190 subjects with knee OA (mean ± SD age 60.2 ± 10.4 years, body mass index 32.7 ± 7.2 kg/m(2) ) were obtained from a randomized controlled trial. Knee pain was measured using the Western Ontario and McMaster Universities Osteoarthritis Index, and health-related quality of life was assessed using the Short Form 36 (SF-36). One-repetition maximum (1RM) strength was assessed using the bilateral leg press, and peak muscle power was measured during 5 maximum voluntary velocity repetitions at 40% and 70% of 1RM. In univariate analysis, greater muscle power was significantly associated with pain (r = -0.17, P < 0.02) and also significantly and positively associated with SF-36 physical component summary (PCS) scores (r = 0.16, P < 0.05). After adjustment for multiple covariates, muscle power was a significant independent predictor of pain (P ≤ 0.05) and PCS scores (P ≤ 0.04). However, muscle strength was not an independent determinant of pain or quality of life (P ≥ 0.06). Muscle power is an independent determinant of pain and quality of life in knee OA. Compared to strength, muscle power may be a more clinically important measure of muscle function within this population. New trials to systematically examine the impact of muscle power training interventions on disease severity in knee OA are particularly warranted. © 2015, American College of Rheumatology.

  1. The Impact of Transformer Winding Connections of A Grid-Connected PV on Voltage Quality Improvement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muljadi, Eduard; Tumbelaka, Hanny H.; Gao, Wenzhong

    In this paper, the high-power PV plant is connected to the weak grid by means of a three-phase power transformer. The selection of transformer winding connection is critical especially when the PV inverter has a reactive power controller. In general, transformer winding connection can be arranged in star-star (with neutral earthed) or star-delta. The reactive power controller supports voltage regulation of the power system particularly under transient faults. Its control strategy is based on utilizing the grid currents to make a three-phase reactive unbalanced current with a small gain. The gain is determined by the system impedance. Simulation results exhibitmore » that the control strategy works very well particularly under disturbance conditions when the transformer winding connection is star-star with both neutrals grounded. The power quality in terms of the voltage quality is improved.« less

  2. 1030 nm high power polarization maintained fiber laser with narrow linewidth and near-diffraction-limited beam quality

    NASA Astrophysics Data System (ADS)

    Chu, Qiuhui; Zhao, Pengfei; Li, Chengyu; Wang, Bopeng; Lin, Honghuan; Guo, Chao; Liu, Yu; Jing, Feng; Tang, Chuanxiang

    2018-03-01

    A high power 1030 nm ytterbium-doped polarization maintained fiber laser with optimized parameters is presented in this paper. The master oscillator power amplifier system with counter-pumped amplifier is established. The output power is 900 W, along with a light-to-light efficiency of 64.2%. The amplified spontaneous emission suppression ratio of spectrum reaches to 40 dB with 3 dB linewidth of 0.14 nm. The polarization extinction ratio is 12 dB, and the beam quality factor is M2x=1.07, M2y=1.12. To the best of our knowledge, this is the first demonstration of 1030 nm high power fiber laser with narrow linewidth, near linear polarization, and neardiffraction-limited beam quality

  3. Air pollution effects due to deregulation of the electric industry

    NASA Astrophysics Data System (ADS)

    Davoodi, Khojasteh Riaz

    The Energy Policy Act of 1992 introduced the concept of open-access into the electric utility industry which allows privately-owned utilities to transmit power produced by non-utility generators and independent power producers (IPPs). In April 1996, the Federal Energy Regulatory Commission (FERC) laid down the final rules (Orders No. 888 & No. 889), which required utilities to open their transmission lines to any power producer and charge them no more than what they pay for the use of their own lines. These rules set the stage for the retail sale of electricity to industrial, commercial and residential utility customers; non-utility generators (Nugs); and power marketers. These statutory, regulatory and administrative changes create for the electric utility industry two different forces that contradict each other. The first is the concept of competition among utility companies; this places a greater emphasis on electric power generation cost control and affects generation/fuel mix selection and demand side management (DSM) activities. The second force, which is converse to the first, is that utilities are major contributors to the air pollution burden in the United States and environmental concerns are forcing them to reduce emissions of air pollutants by using more environmentally friendly fuels and implementing energy saving programs. This study evaluates the impact of deregulation within the investor owned electric utilities and how this deregulation effects air quality by investigating the trend in demand side management programs and generation/fuel mix. A survey was conducted of investor owned utilities and independent power producers. The results of the survey were analyzed by analysis of variance and regression analysis to determine the impact to Air Pollution. An air Quality Impact model was also developed in this study. This model consists of six modules: (1) demand side management and (2) consumption of coal, (3) gas, (4) renewable, (5) oil and (6) nuclear sources until the year 2005. Each module was analyzed separately and the result from each module was transferred into the Air Quality Impact model. The model assesses the changes in electricity generation within each module due to deregulation and these changes can then be correlated to the emission of air pollutants in the United States.

  4. Effect of postharvest spray of apple polyphenols on the quality of fresh-cut red pitaya fruit during shelf life.

    PubMed

    Fan, Panhui; Huber, Donald J; Su, Zihan; Hu, Meijiao; Gao, Zhaoyin; Li, Min; Shi, Xuequn; Zhang, Zhengke

    2018-03-15

    Fresh-cut (FC) red pitaya fruit were treated with 5ga.i.l -1 apple polyphenols (APP) and then stored at 20°C for up to 4days to evaluate the effects on attributes. Results showed that FC pitaya fruit with APP treatment showed greater colour retention, delayed softening, reduced loss of soluble solids content, titratable acidity, betacyanin and total phenolics compared with untreated FC fruit. APP treatment also maintained antioxidant activity, as indicated by higher DPPH radical-scavenging activity and reducing power compared with untreated FC pitaya fruit. APP treatment strongly suppressed microbial growth, contributing to improvement of product safety. Because APP is a natural product, we propose that application of APP could be a convenient, safe and low-cost approach to maintain the quality and extend the shelf life of FC red pitaya fruit. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Sodium D2 resonance radiation in single-pass sum-frequency generation with actively mode-locked Nd:YAG lasers

    NASA Astrophysics Data System (ADS)

    Saito, Norihito; Akagawa, Kazuyuki; Ito, Mayumi; Takazawa, Akira; Hayano, Yutaka; Saito, Yoshihiko; Ito, Meguru; Takami, Hideki; Iye, Masanori; Wada, Satoshi

    2007-07-01

    We report on a sodium D2 resonance coherent light source achieved in single-pass sum-frequency generation in periodically poled MgO-doped stoichiometric lithium tantalate with actively mode-locked Nd:YAG lasers. Mode-locked pulses at 1064 and 1319 nm are synchronized with a time resolution of 37 ps with the phase adjustment of the radio frequencies fed to acousto-optic mode lockers. An output power of 4.6 W at 589.1586 nm is obtained, and beam quality near the diffraction limit is also achieved in a simple design.

  6. Sodium D2 resonance radiation in single-pass sum-frequency generation with actively mode-locked Nd:YAG lasers.

    PubMed

    Saito, Norihito; Akagawa, Kazuyuki; Ito, Mayumi; Takazawa, Akira; Hayano, Yutaka; Saito, Yoshihiko; Ito, Meguru; Takami, Hideki; Iye, Masanori; Wada, Satoshi

    2007-07-15

    We report on a sodium D(2) resonance coherent light source achieved in single-pass sum-frequency generation in periodically poled MgO-doped stoichiometric lithium tantalate with actively mode-locked Nd:YAG lasers. Mode-locked pulses at 1064 and 1319 nm are synchronized with a time resolution of 37 ps with the phase adjustment of the radio frequencies fed to acousto-optic mode lockers. An output power of 4.6 W at 589.1586 nm is obtained, and beam quality near the diffraction limit is also achieved in a simple design.

  7. An ultra-high input impedance ECG amplifier for long-term monitoring of athletes.

    PubMed

    Gargiulo, Gaetano; Bifulco, Paolo; Cesarelli, Mario; Ruffo, Mariano; Romano, Maria; Calvo, Rafael A; Jin, Craig; van Schaik, André

    2010-01-01

    We present a new, low-power electrocardiogram (ECG) recording system with an ultra-high input impedance that enables the use of long-lasting, dry electrodes. The system incorporates a low-power Bluetooth module for wireless connectivity and is designed to be suitable for long-term monitoring during daily activities. The new system using dry electrodes was compared with a clinically approved ECG reference system using gelled Ag/AgCl electrodes and performance was found to be equivalent. In addition, the system was used to monitor an athlete during several physical tasks, and a good quality ECG was obtained in all cases, including when the athlete was totally submerged in fresh water.

  8. Remote-site power generation opportunities for Alaska

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, M.L.

    1997-03-01

    The Energy and Environmental Research Center (EERC) has been working with the Federal Energy Technology Center in Morgantown, West Virginia, to assess options for small, low-cost, environmental acceptable power generation for application in remote areas of Alaska. The goal of this activity was to reduce the use of fuel in Alaskan villages by developing small, low-cost power generation applications. Because of the abundance of high-quality coal throughout Alaska, emphasis was placed on clean coal applications, but other energy sources, including geothermal, wind, hydro, and coalbed methane, were also considered. The use of indigenous energy sources would provide cheaper cleaner power,more » reduce the need for PCE (Power Cost Equalization program) subsidies, increase self-sufficiency, and retain hard currency in the state while at the same time creating jobs in the region. The introduction of economical, small power generation systems into Alaska by US equipment suppliers and technology developers aided by the EERC would create the opportunities for these companies to learn how to engineer, package, transport, finance, and operate small systems in remote locations. All of this experience would put the US developers and equipment supply companies in an excellent position to export similar types of small power systems to rural areas or developing countries. Thus activities in this task that relate to determining the generic suitability of these technologies for other countries can increase US competitiveness and help US companies sell these technologies in foreign countries, increasing the number of US jobs. The bulk of this report is contained in the two appendices: Small alternative power workshop, topical report and Global market assessment of coalbed methane, fluidized-bed combustion, and coal-fired diesel technologies in remote applications.« less

  9. An integrative review of health-related quality of life in patients with critical limb ischaemia.

    PubMed

    Monaro, Susan; West, Sandra; Gullick, Janice

    2017-10-01

    To examine the domains and the domain-specific characteristics within a peripheral arterial disease health-related quality of life framework for their usefulness in defining critical limb ischaemia health-related quality of life. Critical Limb Ischaemia presents a highly individualised set of personal and health circumstances. Treatment options include conservative management, revascularisation or amputation. However, the links between treatment decisions and quality of life require further investigation. The framework for this integrative review was the peripheral arterial disease-specific health-related quality of life domains identified by Treat-Jacobson et al. The literature expanded and refined Treat-Jacobson's framework by modifying the characteristics to better describe health-related quality of life in critical limb ischaemia. Given that critical limb ischaemia is a highly individualised situation with powerful health-related quality of life implications, further research focusing on patient and family-centred decision-making relating to therapeutic options and advanced care planning is required. A critical limb ischaemia-specific, health-related quality of life tool is required to capture both the unique characteristics of this disorder, and the outcomes for active or conservative care among this complex group of patients. © 2016 John Wiley & Sons Ltd.

  10. Anomaly Detection in Power Quality at Data Centers

    NASA Technical Reports Server (NTRS)

    Grichine, Art; Solano, Wanda M.

    2015-01-01

    The goal during my internship at the National Center for Critical Information Processing and Storage (NCCIPS) is to implement an anomaly detection method through the StruxureWare SCADA Power Monitoring system. The benefit of the anomaly detection mechanism is to provide the capability to detect and anticipate equipment degradation by monitoring power quality prior to equipment failure. First, a study is conducted that examines the existing techniques of power quality management. Based on these findings, and the capabilities of the existing SCADA resources, recommendations are presented for implementing effective anomaly detection. Since voltage, current, and total harmonic distortion demonstrate Gaussian distributions, effective set-points are computed using this model, while maintaining a low false positive count.

  11. Effects of Active Sting Damping on Common Research Model Data Quality

    NASA Technical Reports Server (NTRS)

    Acheson, Michael J.; Balakrishna, S.

    2011-01-01

    Recent tests using the Common Research Model (CRM) at the Langley National Transonic Facility (NTF) and the Ames 11-foot Transonic Wind Tunnel (11' TWT) produced large sets of data that have been used to examine the effects of active damping on transonic tunnel aerodynamic data quality. In particular, large statistically significant sets of repeat data demonstrate that the active damping system had no apparent effect on drag, lift and pitching moment repeatability during warm testing conditions, while simultaneously enabling aerodynamic data to be obtained post stall. A small set of cryogenic (high Reynolds number) repeat data was obtained at the NTF and again showed a negligible effect on data repeatability. However, due to a degradation of control power in the active damping system cryogenically, the ability to obtain test data post-stall was not achieved during cryogenic testing. Additionally, comparisons of data repeatability between NTF and 11-ft TWT CRM data led to further (warm) testing at the NTF which demonstrated that for a modest increase in data sampling time, a 2-3 factor improvement in drag, and pitching moment repeatability was readily achieved not related with the active damping system.

  12. Beyond Electric Propulsion: Non-Propulsive Benefits of Nuclear Power for the Exploration of the Outer Solar System

    NASA Astrophysics Data System (ADS)

    Zubrin, Robert M.

    1994-07-01

    In the past, most studies dealing with the benefits of space nuclear electric power systems for solar system exploration have focused on the potential of nuclear electric propulsion (NEP) to enhance missions by increasing delivered payload, decreasing LEO mass, or reducing trip time. While important, such mission enhancements have failed to go to the heart of the concerns of the scientific community supporting interplanetary exploration. To put the matter succinctly, scientists don't buy delivered payload - they buy data returned. With nuclear power we can increase both the quantity of data returned, by enormously increasing data communication rates, and the quality of data by enabling a host of active sensing techniques otherwise impossible. These non-propulsive mission enhancement capabilities of space nuclear power have been known in principle for many years, but they have not been adequately documented. As a result, support for the development of space nuclear power by the interplanetary exploration community has been much less forceful than it might otherwise be. In this paper we shall present mission designs that take full advantage of the potential mission enhancements offered by space nuclear power systems in the 10 to 100 kWe range, not just for propulsion, but to radically improve, enrich, and expand the science return itself. Missions considered include orbiter missions to each of the outer planets. It will be shown that be using hybrid trajectories combining chemical propulsion with NEP and (in certain cases) gravity assists, that it is possible, using a Titan IV-Centaur launch vehicle, for high-powered spacecraft to be placed in orbit around each of the outer planets with electric propulsion burn times of less than 4 years. Such hybrid trajectories therefore make the outer solar-system available to near-term nuclear electric power systems. Once in orbit, the spacecraft will utilize multi-kilowatt communication systems, similar to those now employed by the U.S. military, to increase data return far beyond that possible utilizing the 40 W rf traveling wave tube antennas that are the current NASA standard. This higher data rate will make possible very high resolution multi-spectral imaging (with high resolutions both spatially and spectrally), a form of science hitherto impossible in the outer solar system. Large numbers of such images could be returned, allowing the creation of motion pictures of atmospheric phenomenon on a small scale and greatly increasing the probability of capturing transient phenomena such as lighting or volcanic activity. The multi-kilowatt power sources on the spacecraft also enables active sensing, including radar, which could be used to do topographic and subsurface studies of clouded bodies such as Titan, ground penetrating sounding of Pluto, the major planet's moons, and planetoids, and topside sounding of the electrically conductive atmospheres of Jupiter, Saturn, Uranus and Neptune to produce profiles of fluid density, conductivity, and horizontal and vertical velocity as a function of depth and global location. Radio science investigations of planetary atmospheres and ring systems would be greatly enhanced by increased transmitter power. The scientific benefits of utilizing such techniques are discussed, and a comparison is made with the quantity and quality of science that a low-powered spacecraft employing RTGs could return. It is concluded that the non-propulsive benefits of nuclear power for spacecraft exploring the outer solar system are enormous, and taken together with the well documented mission enhancements enabled by electric propulsion fully justify the expenditures needed to bring a space qualified nuclear electric power source into being.

  13. Maximizing the science return of interplanetary missions using nuclear electric power

    NASA Astrophysics Data System (ADS)

    Zubrin, Robert M.

    1995-01-01

    In the past, most studies dealing with the benefits of space nuclear electric power systems for solar system exploration have focused on the potential of nuclear electric propulsion (NEP) to enhance missions by increasing delivered payload, decreasing LEO mass, or reducing trip time. While important, such mission enhancements have failed to go to the heart of the concerns of the scientific community supporting interplanetary exploration. To put the matter succintly, scientists don't buy delivered payload—they buy data returned. With nuclear power we can increase both the quantity of data returned, by enormously increasing data communication rates, and the quality of data by enabling a host of active sensing techniques otherwise impossible. These non-propulsive mission enhancement capabilities of space nuclear power have been known in principle for many years, but they have not been adequately documented. As a result, support for the development of space nuclear power by the interplanetary exploration community has been much less forceful than it might otherwise be. In this paper we shall present mission designs that take full advantage of the potential mission enhancements offered by space nuclear power systems in the 15 to 30 kWe range, not just for propulsion, but to radically improve, enrich, and expand the science return itself. Missions considered include orbiter missions to each of the outer planets. It will be shown that by using hybrid trajectories combining chemical propulsion with NEP and (in certain cases) gravity assists, that it is possible, using Proton, Tatan III or Titan IV-Centaur launch vehicles, for high-powered spacecraft to be placed in orbit around each of the outer planets with electric propulsion burn times of less than 4 years. Such hybrid trajectories therefore make the outer solar-system available to near-term nuclear electric power systems. Once in orbit, the spacecraft will utilize multi-kilowatt communication systems, similar to those now employed by the U.S. military, to increse data return far beyond that possible utilizing the 40 W rf traveling wave tube antennas that are the current NASA stadard. This higher data rate will make possible very high resolution multi-space imaging (with high resolutions both spatially and spectrally), a form of science hitherto impossible in the outer solar system. Larger numbers of such images could be returned, allowing the creation of motion pictures of atmospheric phenomenon on a small scale and greatly increasing the probability of capturing transient phenomena such as lighting or volcanic activity. The multi-kilowatt power sources on the spaecraft also enables active sensing, including radar, which could be used to do topographic and subsurface studies of clouded bodies such as Titan, ground pentrating sounding of Pluto, the major planet's moons, and planetoids, and topside sounding of the electrically conductive atmospheres of Jupiter, Saturn, Uranus and Neptune to produce profiles of fluid density, conductivity, and horizontal and vertical velocity as a function of depth and global location. Radio science investigations of planetary atmospheres and ring systems would be greatly enhanced by increased transmitter power. The scientific benefits of utilizing such techniques are discussed, and a comparison is made with the quantity and quality of science that a low-powered spacecraft employing RTGs could return. It is concluded that the non-propulsive benefits of nuclear power for spacecraft exploring the outer solar system are enormous, and taken together with the well documented mission enhancements enabled by electric propulsion fully justify the expanditures needed to bring a space qualified nuclear electric power source into being.

  14. Statistical analysis and modeling of the temperature-dependent sleep behavior of drosophila

    NASA Astrophysics Data System (ADS)

    Shih, Chi-Tin; Lin, Hsuan-Wen; Chiang, Ann-Shyn

    2011-01-01

    The sleep behavior of drosophila is analyzed under different temperatures. The activity per minute of the flies is recorded automatically. Sleep for a fruit fly is defined as the periods without any activity and longer than 5 minutes. Several parameters such as total sleep time, circadian sleep profile, quality of sleep are analyzed. The sleep behaviors are significantly different for flies at different temperature. Interestingly, the durations of daytime sleep periods show a common scale-free power law distribution. We propose a stochastic model to simulate the activities of the population of neurons which regulate the dynamics of sleep-wake process to explain the distribution of daytime sleep.

  15. A grid-connected single-phase photovoltaic micro inverter

    NASA Astrophysics Data System (ADS)

    Wen, X. Y.; Lin, P. J.; Chen, Z. C.; Wu, L. J.; Cheng, S. Y.

    2017-11-01

    In this paper, the topology of a single-phase grid-connected photovoltaic (PV) micro-inverter is proposed. The PV micro-inverter consists of DC-DC stage with high voltage gain boost and DC-AC conversion stage. In the first stage, we apply the active clamp circuit and two voltage multipliers to achieve soft switching technology and high voltage gain. In addition, the flower pollination algorithm (FPA) is employed for the maximum power point tracking (MPPT) in the PV module in this stage. The second stage cascades a H-bridge inverter and LCL filter. To feed high quality sinusoidal power into the grid, the software phase lock, outer voltage loop and inner current loop control method are adopted as the control strategy. The performance of the proposed topology is tested by Matlab/Simulink. A PV module with maximum power 300W and maximum power point voltage 40V is applied as the input source. The simulation results indicate that the proposed topology and the control strategy are feasible.

  16. High-power actively Q-switched single-mode 1342 nm Nd:YVO4 ring laser, injection-locked by a cw single-frequency microchip laser.

    PubMed

    Koch, Peter; Bartschke, Juergen; L'huillier, Johannes A

    2015-11-30

    In this paper we report on the realization of a single-mode Q-switched Nd:YVO4 ring laser at 1342 nm. Unidirectional and single-mode operation of the ring laser is achieved by injection-locking with a continuous wave Nd:YVO4 microchip laser, emitting a single-frequency power of up to 40 mW. The ring laser provides a single-mode power of 13.9 W at 10 kHz pulse repetition frequency with a pulse duration of 18.2 ns and an excellent beam quality (M2 < 1.05). By frequency doubling of the fundamental 1342 nm laser, a power of 8.7 W at 671 nm with a pulse duration of 14.8 ns and a beam propagation factor of M2 < 1.1 is obtained. The 671 nm radiation features a long-term spectral width of 75 MHz.

  17. High Temperature, High Power Piezoelectric Composite Transducers

    PubMed Central

    Lee, Hyeong Jae; Zhang, Shujun; Bar-Cohen, Yoseph; Sherrit, StewarT.

    2014-01-01

    Piezoelectric composites are a class of functional materials consisting of piezoelectric active materials and non-piezoelectric passive polymers, mechanically attached together to form different connectivities. These composites have several advantages compared to conventional piezoelectric ceramics and polymers, including improved electromechanical properties, mechanical flexibility and the ability to tailor properties by using several different connectivity patterns. These advantages have led to the improvement of overall transducer performance, such as transducer sensitivity and bandwidth, resulting in rapid implementation of piezoelectric composites in medical imaging ultrasounds and other acoustic transducers. Recently, new piezoelectric composite transducers have been developed with optimized composite components that have improved thermal stability and mechanical quality factors, making them promising candidates for high temperature, high power transducer applications, such as therapeutic ultrasound, high power ultrasonic wirebonding, high temperature non-destructive testing, and downhole energy harvesting. This paper will present recent developments of piezoelectric composite technology for high temperature and high power applications. The concerns and limitations of using piezoelectric composites will also be discussed, and the expected future research directions will be outlined. PMID:25111242

  18. Double Q-switch Ho:Sc2SiO5 laser by acousto-optic modulator combined with Cr2+:ZnSe saturable absorber

    NASA Astrophysics Data System (ADS)

    Yang, Xiao-tao; Zhang, Peng; Xie, Wen-qiang; Li, Lin-jun

    2018-01-01

    A double Q-switch (DQS) Ho:Sc2SiO5 laser modulated by a acousto-optic modulators (AOM) combined with a Cr2+:ZnSe saturable absorber (SA) was reported for the first time. The actively Q-switch (AQS) and passively Q-switch (PQS) were also studied. For the DQS mode, a maximum average output power of 2.49 W under the incident pump power of 12.5 W was obtained, corresponding to a slope efficiency of 24%. The characteristics of the DQS Ho:SSO laser versus different repetition frequencies (RF) of the AOM were researched. The maximum single-pulse energy of the DQS Ho:SSO laser was calculated to 1.98 mJ. The maximum peak power of the DQS Ho:SSO laser was 49.5 kW. The output beam quality factor M2 of DQS Ho:SSO laser was measured to be 1.15 with the highest peak power by knife-edge method at different positions.

  19. Adaptive neuro-fuzzy and expert systems for power quality analysis and prediction of abnormal operation

    NASA Astrophysics Data System (ADS)

    Ibrahim, Wael Refaat Anis

    The present research involves the development of several fuzzy expert systems for power quality analysis and diagnosis. Intelligent systems for the prediction of abnormal system operation were also developed. The performance of all intelligent modules developed was either enhanced or completely produced through adaptive fuzzy learning techniques. Neuro-fuzzy learning is the main adaptive technique utilized. The work presents a novel approach to the interpretation of power quality from the perspective of the continuous operation of a single system. The research includes an extensive literature review pertaining to the applications of intelligent systems to power quality analysis. Basic definitions and signature events related to power quality are introduced. In addition, detailed discussions of various artificial intelligence paradigms as well as wavelet theory are included. A fuzzy-based intelligent system capable of identifying normal from abnormal operation for a given system was developed. Adaptive neuro-fuzzy learning was applied to enhance its performance. A group of fuzzy expert systems that could perform full operational diagnosis were also developed successfully. The developed systems were applied to the operational diagnosis of 3-phase induction motors and rectifier bridges. A novel approach for learning power quality waveforms and trends was developed. The technique, which is adaptive neuro fuzzy-based, learned, compressed, and stored the waveform data. The new technique was successfully tested using a wide variety of power quality signature waveforms, and using real site data. The trend-learning technique was incorporated into a fuzzy expert system that was designed to predict abnormal operation of a monitored system. The intelligent system learns and stores, in compressed format, trends leading to abnormal operation. The system then compares incoming data to the retained trends continuously. If the incoming data matches any of the learned trends, an alarm is instigated predicting the advent of system abnormal operation. The incoming data could be compared to previous trends as well as matched to trends developed through computer simulations and stored using fuzzy learning.

  20. The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

    DTIC Science & Technology

    2017-09-01

    parallel, randomized, controlled clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of...clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of motion and active power, will...Department of the Army position, policy or decision unless so designated by other documentation. CONTRACTING ORGANIZATION: University of Tennessee

  1. Using Temporal Fill Factor to Reduce Frame Reconstruction Rates

    NASA Technical Reports Server (NTRS)

    Larimer, James; Balram, Nikhil; Gille, Jennifer; Luszcz, Jeffery

    1997-01-01

    The newer active matrix display technologies such as TFT-LCD, DMD, PDP maintain their pixel values through the entire frame time, presenting a 100% temporal fill factor, in contrast to the duty cycle produced by the phosphor impulse response of the CRT. This sample-and-hold characteristic can be exploited to lower the displayed frame rate without affecting visual quality. The lower frame rate results in significantly lower transmission bandwidth, power, and cost.

  2. Enhancing and Evaluating Scientific Argumentation in the Inquiryoriented College Chemistry Classroom

    NASA Astrophysics Data System (ADS)

    D'Souza, Annabel Nica

    The research presented in chapters 2, 3, and 4 in this dissertation uses a sociocultural and sociohistorical lens, particularly around power, authority of knowledge and identity formation, to investigate the complexity of engaging in, supporting, and evaluating high-quality argumentation within a college biochemistry inquiry-oriented classroom. Argumentation skills are essential to college and career (National Research Council, 2010) and for a democratic citizenry. It is central to science teaching and learning (Osborne et al., 2004a) and can deepen content knowledge (Jimenez-Aleixandre et al., 2000; Jimenez-Aleixandre & Pereiro-Munhoz, 2002). When students have opportunities to make claims and support it with evidence and reasoning they may also increase their problem-solving and critical thinking capacity (Case, 2005; Willingham, 2007). Overall, this has implications in supporting students to become increasingly literate in scientific ideas, language, and practices. However, supporting argumentation can be challenging for instructors, particularly in designing leaning environments that facilitate and evaluate both the process and the product during student discussions (Duschl & Osborne, 2002). Fostering argumentation is complex and requires explicit modeling and multiple opportunities for dialogic interactions. This dissertation will examine how several facets influence argumentation in order to support instructors in implementing and improving argumentation in their inquiry-oriented classrooms. These facets include access to language and use of discursive moves, classroom design, curriculum and instructional activities, and interactional dynamics and power negotiation. The data set for this dissertation is a transcript generated from the audio- and video capture of a 7-minute student discussion around a mechanism in the TCA (TriCarboxylic Acid) cycle, as well as student writing, and course documents from student portfolios. This dissertation, organized using the manuscript style structure, will present three standalone chapters, each with a specific focus related to the central theme of supporting argumentation, which is the connecting thread. Chapter 2 will discuss how power is negotiated during the argumentation process and how interaction dynamics can support or inhibit the quality of argumentation. Chapter 3 will provide assessment and evaluation support to instructors who want to guide their students in meeting high quality levels in both the process and product of argumentation. Finally, chapter 4 will explore the influence of pedagogical, and instructional resources and tools on the quality of argumentation. This includes a discussion of the influence of classroom talk, particularly discursive moves and interactional dynamics, as well the curriculum and instructional activities, and the design features of the learning environment. Each chapter will conclude with instructional implications that provide practical guidance in the form of pedagogical activities to instructors. Partial funding for this dissertation was received from a PSC-CUNY Cycle 44 Research Award (66799-00 44). Findings suggest that the classroom design can support collaboration and the dialogic nature of argumentation, and the curriculum and activities can act as resources for students to share and negotiate multiple perspectives, but that instructors can also influence the process of argumentation by utilizing specific discursive moves, such as telling and revoicing, to promote or inhibit argumentation. The results, specifically from chapter 4, also propose that instructors model and share the expected criteria for high quality components of argumentation. The need for instructors to be aware of the criteria for high levels of quality for each of the argumentation components is a critical implication of this research. The criterion is presented in this dissertation and is derived from a review of multiple findings by researchers of argumentation, as well the scientific community at large. Creating structures and implementing targeted pedagogical strategies that support argumentation can lead students to use the process of argumentation as an empowerment tool to enact agency and negotiate power. This has the potential to sustain the success of science students, create a community of practice, and increase equity and access for all.

  3. New Approach to Optimize the Apfs Placement Based on Instantaneous Reactive Power Theory by Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Hashemi-Dezaki, Hamed; Mohammadalizadeh-Shabestary, Masoud; Askarian-Abyaneh, Hossein; Rezaei-Jegarluei, Mohammad

    2014-01-01

    In electrical distribution systems, a great amount of power are wasting across the lines, also nowadays power factors, voltage profiles and total harmonic distortions (THDs) of most loads are not as would be desired. So these important parameters of a system play highly important role in wasting money and energy, and besides both consumers and sources are suffering from a high rate of distortions and even instabilities. Active power filters (APFs) are innovative ideas for solving of this adversity which have recently used instantaneous reactive power theory. In this paper, a novel method is proposed to optimize the allocation of APFs. The introduced method is based on the instantaneous reactive power theory in vectorial representation. By use of this representation, it is possible to asses different compensation strategies. Also, APFs proper placement in the system plays a crucial role in either reducing the losses costs and power quality improvement. To optimize the APFs placement, a new objective function has been defined on the basis of five terms: total losses, power factor, voltage profile, THD and cost. Genetic algorithm has been used to solve the optimization problem. The results of applying this method to a distribution network illustrate the method advantages.

  4. International water and steam quality standards on thermal power plants at all-volatile treatment

    NASA Astrophysics Data System (ADS)

    Petrova, T. I.; Orlov, K. A.; Dooley, R. B.

    2016-12-01

    One of the methods for the improvement of reliability and efficiency of the equipment at heat power plants is the decrease in the rate of corrosion of structural materials and sedimentation in water/steam circuit. These processes can be reduced to minimum by using the water with low impurity content and coolant treatment. For many years, water and steam quality standards were developed in various countries (United States, Germany, Japan, etc.) for specific types of equipment. The International Association for the Properties of Water and Steam (IAPWS), which brings together specialists from 21 countries, developed the water and steam quality standards for various types of power equipment based on theoretical studies and long-term operating experience of power equipment. Recently, various water-chemistry conditions are applied on heatpower equipment including conventional boilers and HRSGs with combined cycle power plants (Combined Cycle Power Plants (CCPP)). In paper, the maintenance conditions of water chemistry with ammonia or volatile amine dosing are described: reducing AVT(R), oxidizing AVT(O), and oxygen OT. Each of them is provided by the water and steam quality standards and recommendations are given on their maintenance under various operation conditions. It is noted that the quality control of heat carrier must be carried out with a particular care on the HPPs with combined cycle gas turbine units, where frequent starts and halts are performed.

  5. Ground-based and in-flight simulator studies of low-speed handling characteristics of two supersonic cruise transport concepts

    NASA Technical Reports Server (NTRS)

    Grantham, W. D.; Nguyen, L. T.; Deal, P. L.; Neubauer, M. J.; Smith, P. M.; Gregory, F. D.

    1978-01-01

    Conventional and powered lift concepts for supersonic approach and landing tasks are considered. Results indicated that the transport concepts had unacceptable low-speed handling qualities with no augmentation, and that in order to achieve satisfactory handling qualities, considerable augmentation was required. The available roll-control power was acceptable for the powered-lift concept.

  6. TCSC based filtering and improvement of power quality

    NASA Astrophysics Data System (ADS)

    Arulvendhan, K.; Dilli srinivasan, J.; Vinil, M.

    2018-04-01

    Thyristor Controlled Series Capacitor (TCSC) as a dynamic system, also its competence in growing power allocation in transmission lines, can be used to improve different power system problems. TCSC’s dissimilar advantages can be categorised as steady-state and transient ones. During a fault, TCSC can increase power quality by reducing the current and benefit to keep the voltage as high as conceivable. In this paper, the application of TCSC to enrich one of the vital power quality issues, i.e., voltage sag is investigated. Different operating modes of TCSC have dissimilar influences on the voltage of the bus that the line armed with TCSC is connected to. Relocating to bypass mode upon manifestation of a fault is a significant feature of TCSC to advance voltage sag. The simulations on a trial network disclose these facts.

  7. Concept Design for a 1-Lead Wearable/Implantable ECG Front-End: Power Management

    PubMed Central

    George, Libin; Gargiulo, Gaetano Dario; Lehmann, Torsten; Hamilton, Tara Julia

    2015-01-01

    Power supply quality and stability are critical for wearable and implantable biomedical applications. For this reason we have designed a reconfigurable switched-capacitor DC-DC converter that, aside from having an extremely small footprint (with an active on-chip area of only 0.04 mm2), uses a novel output voltage control method based upon a combination of adaptive gain and discrete frequency scaling control schemes. This novel DC-DC converter achieves a measured output voltage range of 1.0 to 2.2 V with power delivery up to 7.5 mW with 75% efficiency. In this paper, we present the use of this converter as a power supply for a concept design of a wearable (15 mm × 15 mm) 1-lead ECG front-end sensor device that simultaneously harvests power and communicates with external receivers when exposed to a suitable RF field. Due to voltage range limitations of the fabrication process of the current prototype chip, we focus our analysis solely on the power supply of the ECG front-end whose design is also detailed in this paper. Measurement results show not just that the power supplied is regulated, clean and does not infringe upon the ECG bandwidth, but that there is negligible difference between signals acquired using standard linear power-supplies and when the power is regulated by our power management chip. PMID:26610497

  8. Concept Design for a 1-Lead Wearable/Implantable ECG Front-End: Power Management.

    PubMed

    George, Libin; Gargiulo, Gaetano Dario; Lehmann, Torsten; Hamilton, Tara Julia

    2015-11-19

    Power supply quality and stability are critical for wearable and implantable biomedical applications. For this reason we have designed a reconfigurable switched-capacitor DC-DC converter that, aside from having an extremely small footprint (with an active on-chip area of only 0.04 mm²), uses a novel output voltage control method based upon a combination of adaptive gain and discrete frequency scaling control schemes. This novel DC-DC converter achieves a measured output voltage range of 1.0 to 2.2 V with power delivery up to 7.5 mW with 75% efficiency. In this paper, we present the use of this converter as a power supply for a concept design of a wearable (15 mm × 15 mm) 1-lead ECG front-end sensor device that simultaneously harvests power and communicates with external receivers when exposed to a suitable RF field. Due to voltage range limitations of the fabrication process of the current prototype chip, we focus our analysis solely on the power supply of the ECG front-end whose design is also detailed in this paper. Measurement results show not just that the power supplied is regulated, clean and does not infringe upon the ECG bandwidth, but that there is negligible difference between signals acquired using standard linear power-supplies and when the power is regulated by our power management chip.

  9. Perceptions of patients and physiotherapists on patient participation: a narrative synthesis of qualitative studies.

    PubMed

    Schoeb, Veronika; Bürge, Elisabeth

    2012-06-01

    Patient participation is nowadays considered important for high quality patient care. Although the literature on health care professions provides some insights into this topic, specific aspects in the field of physiotherapy are less known. The objective of this review was to investigate how patients and physiotherapists perceive patient participation, especially in regards to what it means for them and the role patients play during physiotherapy treatment sessions. We used a narrative synthesis of qualitative studies. We conducted a systematic search in six databases using a set of key words, extracted relevant data, performed quality assessment and synthesized findings from the selected studies. Out of 160 studies, 11 were retained. Two main themes emerged: the conceptualization of patient participation and the patients' role preferences. Patient participation included various activities including goal setting, information exchange, decision-making and exercise training and often influenced the power relation between patient and physiotherapist. Patients' willingness to participate varied, and they often did not play their desired role. Patients and physiotherapists perceived participation to be valuable yet challenging. Problems of conceptualization, power inequalities, lack of health professionals' skills and lack of the right attitude to share power and responsibility from both sides were some of the barriers that impeded optimal participation. Copyright © 2011 John Wiley & Sons, Ltd.

  10. Chronic ozone exposure alters the secondary metabolite profile, antioxidant potential, anti-inflammatory property, and quality of red pepper fruit from Capsicum baccatum.

    PubMed

    Bortolin, Rafael Calixto; Caregnato, Fernanda Freitas; Divan Junior, Armando Molina; Zanotto-Filho, Alfeu; Moresco, Karla Suzana; Rios, Alessandro de Oliveira; Salvi, Aguisson de Oliveira; Ortmann, Caroline Flach; de Carvalho, Pâmela; Reginatto, Flávio Henrique; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca

    2016-07-01

    Tropospheric ozone (O3) background concentrations have increased since pre-industrial times, reaching phytotoxic concentrations in many regions globally. However, the effect of high O3 concentrations on quality of fruit and vegetables remains unknown. Here, we evaluated whether O3 pollution alters the quality of Capsicum baccatum peppers by changing the secondary compound profiles and biological activity of the fruit. C. baccatum pepper plants were exposed to ozone for 62 days in an open-top chamber at a mean O3 concentration of 171.6µg/m(3). Capsaicin levels decreased by 50% in the pericarp, but remained unchanged in the seeds. In contrast, the total carotenoid content increased by 52.8% in the pericarp. The content of total phenolic compounds increased by 17% in the pericarp. The total antioxidant potential decreased by 87% in seeds of O3-treated plants. The seeds contributed more than the pericarp to the total radical-trapping antioxidant potential and total antioxidant reactivity. O3 treatment impaired the ferric-reducing antioxidant power of the seeds and reduced NO(•)-scavenging activity in the pericarp. However, O3 treatment increased ferrous ion-chelating activity and hydroxyl radical-scavenging activity in the pericarp. Our results confirm that O3 alters the secondary metabolite profile of C. baccatum pepper fruits and, consequently, their biological activity profile. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Power Wheelchair Use in Persons With Amyotrophic Lateral Sclerosis: Changes Over Time.

    PubMed

    Ward, Amber Lea; Hammond, Sara; Holsten, Scott; Bravver, Elena; Brooks, Benjamin Rix

    2015-01-01

    The objectives of this study were to survey persons with Amyotrophic Lateral Sclerosis (ALS) at 1 and 6 months after receiving power wheelchairs to determine long-term use, comfort, and function as well as the power wheelchair's impact on daily tasks and quality of life. A 33-question survey and Psychosocial Impact of Assistive Devices Scale (PIADS) were sent 1 month after getting a new power wheelchair; a follow-up survey was sent at 6 months. Based on satisfaction and feature use survey results, at 1 month, 81% of users found the power wheelchair overall comfort to be high, 88% found their overall mobility to be improved, and 95% found it easy to use. Their quality of life increased and pain decreased at 1 and 6 months. According to the PIADS, the power wheelchair gave users increased ability to participate and sense of competence. This study has important results for the ALS community, as it is the first to assess power wheelchair users at 1 and 6 months after power wheelchair procurement. The results demonstrate the impact the power wheelchair has on mobility, psychosocial issues, functional abilities, and quality of life for a person with ALS.

  12. Reading performance with low-vision aids and vision-related quality of life after macular translocation surgery in patients with age-related macular degeneration.

    PubMed

    Nguyen, Nhung X; Besch, Dorothea; Bartz-Schmidt, Karl; Gelisken, Faik; Trauzettel-Klosinski, Susanne

    2007-12-01

    The aim of the present study was to evaluate the power of magnification required, reading performance with low-vision aids and vision-related quality of life with reference to reading ability and ability to carry out day-to-day activities in patients after macular translocation. This study included 15 patients who had undergone macular translocation with 360-degree peripheral retinectomy. The mean length of follow-up was 19.2 +/- 10.8 months (median 11 months). At the final examination, the impact of visual impairment on reading ability and quality of life was assessed according to a modified 9-item questionnaire in conjunction with a comprehensive clinical examination, which included assessment of best corrected visual acuity (BCVA), the magnification power required for reading, use of low-vision aids and reading speed. Patients rated the extent to which low vision restricted their ability to read and participate in other activities that affect quality of life. Responses were scored on a scale of 1.0 (optimum self-evaluation) to 5.0 (very poor). In the operated eye, overall mean postoperative BCVA (distance) was not significantly better than mean preoperative BCVA (0.11 +/- 0.06 and 0.15 +/- 0.08, respectively; p = 0.53). However, 53% of patients reported a subjective increase in visual function after treatment. At the final visit, the mean magnification required was x 7.7 +/- 6.7. A total of 60% of patients needed optical magnifiers for reading and in 40% of patients closed-circuit TV systems were necessary. All patients were able to read newspaper print using adapted low-vision aids at a mean reading speed of 71 +/- 40 words per minute. Mean self-reported scores were 3.2 +/- 1.1 for reading, 2.5 +/- 0.7 for day-to-day activities and 2.7 +/- 3.0 for outdoor walking and using steps or stairs. Patients' levels of dependency were significantly correlated with scores for reading (p = 0.01), day-to-day activities (p < 0.001) and outdoor walking and using steps (p = 0.001). The evaluation of self-reported visual function and vision-related quality of life in patients after macular translocation is necessary to obtain detailed information on treatment effects. Our results indicated improvement in patients' subjective evaluations of visual function, without significant improvement in visual acuity. The postoperative clinical benefits of treatment coincide with subjective benefits in terms of reading ability, quality of life and patient satisfaction. Our study confirms the importance and efficiency of visual rehabilitation with aids for low vision after surgery.

  13. Visible high power fiber coupled diode lasers

    NASA Astrophysics Data System (ADS)

    Köhler, Bernd; Drovs, Simon; Stoiber, Michael; Dürsch, Sascha; Kissel, Heiko; Könning, Tobias; Biesenbach, Jens; König, Harald; Lell, Alfred; Stojetz, Bernhard; Löffler, Andreas; Strauß, Uwe

    2018-02-01

    In this paper we report on further development of fiber coupled high-power diode lasers in the visible spectral range. New visible laser modules presented in this paper include the use of multi single emitter arrays @ 450 nm leading to a 120 W fiber coupled unit with a beam quality of 44 mm x mrad, as well as very compact modules with multi-W output power from 405 nm to 640 nm. However, as these lasers are based on single emitters, power scaling quickly leads to bulky laser units with a lot of optical components to be aligned. We also report on a new approach based on 450 nm diode laser bars, which dramatically reduces size and alignment effort. These activities were performed within the German government-funded project "BlauLas": a maximum output power of 80 W per bar has been demonstrated @ 450 nm. We show results of a 200 μm NA0.22 fiber coupled 35 W source @ 450 nm, which has been reduced in size by a factor of 25 compared to standard single emitter approach. In addition, we will present a 200 μm NA0.22 fiber coupled laser unit with an output power of 135 W.

  14. Application of wireless power transmission systems in wireless capsule endoscopy: an overview.

    PubMed

    Basar, Md Rubel; Ahmad, Mohd Yazed; Cho, Jongman; Ibrahim, Fatimah

    2014-06-19

    Wireless capsule endoscopy (WCE) is a promising technology for direct diagnosis of the entire small bowel to detect lethal diseases, including cancer and obscure gastrointestinal bleeding (OGIB). To improve the quality of diagnosis, some vital specifications of WCE such as image resolution, frame rate and working time need to be improved. Additionally, future multi-functioning robotic capsule endoscopy (RCE) units may utilize advanced features such as active system control over capsule motion, drug delivery systems, semi-surgical tools and biopsy. However, the inclusion of the above advanced features demands additional power that make conventional power source methods impractical. In this regards, wireless power transmission (WPT) system has received attention among researchers to overcome this problem. Systematic reviews on techniques of using WPT for WCE are limited, especially when involving the recent technological advancements. This paper aims to fill that gap by providing a systematic review with emphasis on the aspects related to the amount of transmitted power, the power transmission efficiency, the system stability and patient safety. It is noted that, thus far the development of WPT system for this WCE application is still in initial stage and there is room for improvements, especially involving system efficiency, stability, and the patient safety aspects.

  15. Joint Solar Power Industry and Department of Energy Solar Resource and Meteorological Assessment Project (SOLRMAP)

    NASA Astrophysics Data System (ADS)

    Wilcox, Steve; Myers, Daryl

    2009-08-01

    The U.S. Department of Energy's National Renewable Energy Laboratory has embarked on a collaborative effort with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of concentrating solar thermal power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result will be high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  16. Wireless induction coils embedded in diamond for power transfer in medical implants.

    PubMed

    Sikder, Md Kabir Uddin; Fallon, James; Shivdasani, Mohit N; Ganesan, Kumaravelu; Seligman, Peter; Garrett, David J

    2017-08-26

    Wireless power and data transfer to medical implants is a research area where improvements in current state-of-the-art technologies are needed owing to the continuing efforts for miniaturization. At present, lithographical patterning of evaporated metals is widely used for miniature coil fabrication. This method produces coils that are limited to low micron or nanometer thicknesses leading to high impedance values and thus limiting their potential quality. In the present work we describe a novel technique, whereby trenches were milled into a diamond substrate and filled with silver active braze alloy, enabling the manufacture of small, high cross-section, low impedance microcoils capable of transferring up to 10 mW of power up to a distance of 6 mm. As a substitute for a metallic braze line used for hermetic sealing, a continuous metal loop when placed parallel and close to the coil surface reduced power transfer efficiency by 43%, but not significantly, when placed perpendicular to the microcoil surface. Encapsulation of the coil by growth of a further layer of diamond reduced the quality factor by an average of 38%, which can be largely avoided by prior oxygen plasma treatment. Furthermore, an accelerated ageing test after encapsulation showed that these coils are long lasting. Our results thus collectively highlight the feasibility of fabricating a high-cross section, biocompatible and long lasting miniaturized microcoil that could be used in either a neural recording or neuromuscular stimulation device.

  17. Performance and management of draught animals in agriculture in sub-Saharan Africa: a review.

    PubMed

    Pearson, R A; Vall, E

    1998-10-01

    Use of animal power generally enables farmers in sub-Saharan Africa to increase agricultural production and improve the quality of life. Effective use of working animals depends on an understanding of the capabilities of the animals for work, their husbandry requirements and the factors which can influence their performance. These issues are reviewed in this paper in the context of the use of animal power in agriculture in sub-Saharan Africa. The type of animal used for work determines power available to the farmer. The performance of donkeys, horses and cattle have been compared in work tests. Equids are more suited to rapid low draught activities where their faster speed can be used to advantage. At higher draught forces, where speed is less important, the additional weight and power of cattle are an advantage. Use of heart rate recovery after work gives a reasonable indication of fatigue and fitness of equids, when test conditions are standardized. Although feed requirements for work are generally low, feed quality can be so poor that animals are unable to eat enough to meet energy needs for work, and so lose weight during the work season. However, improvements in work performance are not always seen following supplementary feeding in the dry season and the economics need to be considered in each case. Food availability, diseases and heat stress, the major constraints to performance of draught cattle and donkeys working in sub-Saharan Africa, are discussed.

  18. Characteristics of selected elements of the air quality management system in urban areas in Poland

    NASA Astrophysics Data System (ADS)

    Sówka, Izabela; Kobus, Dominik; Chlebowska Styś, Anna; Zathey, Maciej

    2017-11-01

    Most of Europeans living in cities are exposed to concentrations of air pollutants in excess of the thresholds given in the WHO guidelines and EU legislation. Due to this fact, for the urban air quality systems, the mechanisms of proper information and warning of the inhabitants as well as legal, economic and spatial planning instruments should be improved. The analysis of Polish air quality management system and its' selected components (exemplary measures, information-spreading methods, spatial planning instruments) in four selected Polish cities (Wroclaw, Warsaw, Poznan and Cracow) indicated the need to develop effective solutions, among others, in terms of: emission requirements for combustion of fuels of power of up to 1 MW; admission of high emission fuels on the market; legal and coordination issues at the level of implementation of the area development policy and coordination of activities covering issues within the scope of the structure of planning documents including mainly: ambient air protection programs, spatial developments plans in communes and voivodeships, low emission economy plans, plans of sustainable development of public transport, plans of providing heat, electric power and gas fuels to communes, acts of regional parliaments, introducing limitations based on the Environmental Protection Act and strategies of voivodeship.

  19. Velocity structure of the shallow lunar crust

    NASA Technical Reports Server (NTRS)

    Gangi, A. F.; Yen, T. E.

    1979-01-01

    Data from the thumper shots of the Apollo 14 and Apollo 16 active seismic experiments, testing whether the velocity variation in the shallow lunar crust (depths less than or equal to 10 m) can be represented by a self-compacting-power-layer or by a constant-velocity-layer model, are analyzed. Although filtering and stacking improved the S/N ratios, it was found that measuring the arrival times or amplitudes of arrivals beyond 32 m was not possible. The data quality precluded a definitive distinction between the power-law velocity variation and the layered-velocity model. Furthermore, it was found that the shallow lunar regolith is made up of fine particles, which supports the idea of a 1/6 power-velocity model. Analysis of the amplitudes of first arrivals revealed large errors in the data due to variations in the geophone sensitivities and shot strengths; a least-squares method, that uses data redundancy was employed to eliminate them.

  20. How DRB-XCL burners and air heater upgrade reduced NO sub x and improved efficiency at a western utility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Becker, W.; Stalcup, T.; Schild, V.

    1992-01-01

    The Neil Simpson Unit is a 220,000 lb/hr pulverized coal boiler that was designed to fire a local Wyoming subbituminous coal. During the late 1980s, the Wyoming Department of Air Quality imposed emission limits on the Black Hills Power and Light Co., Neil Simpson Station. The new limits required Black Hills power to control not only particulate and sulfur dioxide (SO{sub 2}) emissions, but also nitrogen oxide (NO{sub x}) emissions. At the same time, Black Hills Power initiated an efficiency improvement study at Neil Simpson Station to investigate methods for reducing net electrical generation costs. This paper addresses the plantmore » efficiency and emissions studies, startup activities, the operating problems and successful operating solutions for NO{sub x} control when firing a Wyoming subbituminous coal. Also included is a summary of the post-0retrofit boiler performance data.« less

  1. AlGaAs heterojunction lasers

    NASA Technical Reports Server (NTRS)

    Goldstein, B.; Pultz, G. N.; Carlin, D. B.; Slavin, S. E.; Ettenberg, M.

    1988-01-01

    The characterization of 8300 A lasers was broadened, especially in the area of beam quality. Modulation rates up to 2 Gbit/sec at output powers of 20 mW were observed, waveform fidelity was fully adequate for low BER data transmission, and wavefront measurements showed that phase aberrations were less than lamda/50. Also, individually addressable arrays of up to ten contiguous diode lasers were fabricated and tested. Each laser operates at powers up to 30 mW CW in single spatial mode. Shifting the operating wavelength of the basic CSP laser from 8300 A to 8650 A was accomplished by the addition of Si to the active region. Output power has reached 100 mW single mode, with excellent far field wave front properties. Operating life is currently approx. 1000 hrs at 35 mW CW. In addition, laser reliability, for operation at both 8300 A and 8650 A, has profited significantly from several developments in the processing procedures.

  2. ATMOSPHERIC AEROSOL SOURCE-RECEPTOR RELATIONSHIPS: THE ROLE OF COAL-FIRED POWER PLANTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Allen L. Robinson; Spyros N. Pandis; Cliff I. Davidson

    2004-12-01

    This report describes the technical progress made on the Pittsburgh Air Quality Study (PAQS) during the period of March 2004 through August 2004. Significant progress was made this project period on the analysis of ambient data, source apportionment, and deterministic modeling activities. Results highlighted in this report include evaluation of the performance of PMCAMx+ for an air pollution episode in the Eastern US, an emission profile for a coke production facility, ultrafine particle composition during a nucleation event, and a new hybrid approach for source apportionment. An agreement was reached with a utility to characterize fine particle and mercury emissionsmore » from a commercial coal fired power. Research in the next project period will include source testing of a coal fired power plant, source apportionment analysis, emission scenario modeling with PMCAMx+, and writing up results for submission as journal articles.« less

  3. Surface-enhanced Raman spectroscopy on litographically constructed microelectrodes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhelyaskov, V.R.; Milne, E.T.; Weldon, M.K.

    1995-12-31

    A novel silicon substrate microelectrode array has been demonstrated to function as a surface-enhanced Raman Spectroscopy (SERS) microelectrode. SERS from adenosine and pyridine down to 10 mM concentration on silver coated iridium and gold microelectrode arrays have been observed with excitation at 532 nm and 633 nm correspondingly. Ag/AgCl reference electrode and platinum or integrated on the microelectrode iridium counter electrodes were used. Owing to the small area of the activated sites on the microelectrode (10 mm x 15 mm) the SERS signal exhibited a strong laser power dependence. The optimal laser power on the activated site was shown tomore » be in the order of x 100 mW. Good quality SERS spectra were recorded with exposure times of 10s and less. The small size of the electrodes makes them promising for studies in confined spaces. This includes potential applications as capillary electrophoreses detectors and probes of chemistry of biological organisms. A work on detection of lipids adhered to self-organized monolayers (SAM)s of alkanethiols on the activated microelectrodes is in progress.« less

  4. [Determination of the effectiveness of certain physical conditioning apparatuses for development of muscle quality].

    PubMed

    Lagassé, P; Godin, G; Brunelle, J; Brunelle, J P

    1982-03-01

    This study attempted to compare on twenty male subjects the intensity of muscular activity during selected exercises executed with and without physical fitness gadgets. Each subject executed two exercises with or without the Total Body Shaper, three exercises with or without the Power X and one exercise with or without the Prone Cycle. The electrical activity of four muscles was studied for each exercise; theoretical data and the publicity of the manufactures were utilized to select the muscles. The statistical analysis showed that exercises executed with the Total Body Shaper are generally less solicitating than similar exercises executed without the gadget, that the Power X has evident advantages for the muscle groups that it activates but that its manufacturers tend to generalize its effects to muscle groups that it does not solicitate and, finally, that the Prone Cycle is the least valuable of the gadgets tested. The results enlighten the need for consumer protection agencies to look more carefully at the publicity utilized to promote the benefits of physical fitness gadgets.

  5. International water and steam quality standards for thermal power station drum-type and waste heat recovery boilers with the treatment of boiler water with phosphates and NaOH

    NASA Astrophysics Data System (ADS)

    Petrova, T. I.; Orlov, K. A.; Dooley, R. B.

    2017-01-01

    One of the ways for improving the operational reliability and economy of thermal power station equipment, including combined-cycle equipment, is to decrease the rates of the corrosion of constructional materials and the formation of scales in the water-steam circuit. These processes can be reduced to a minimum via the use of water with a minimum content of admixtures and the correction treatment of a heat-transfer fluid. The International Association for the Properties of Water and Steam (IAPWS), which unites specialists from every country of the world, has developed water and steam quality standards for power station equipment of different types on the basis of theoretical studies and long-term experience in the operation of power plants in 21 countries. Different water chemistry regimes are currently used at conventional and combined-cycle thermal power stations. This paper describes the conditions for the implementation of water chemistry regimes with the use of sodium salts of phosphoric acid and NaOH for the quality correction of boiler water. Water and steam quality standards and some recommendations for their maintenance under different operational conditions are given for each of the considered water chemistry regimes. The standards are designed for the water-steam circuit of conventional and combined-cycle thermal power stations. It is pointed out that the quality control of a heat-transfer fluid must be especially careful at combined-cycle thermal power stations with frequent startups and shutdowns.

  6. N-Acetylmannosamine improves sleep-wake quality in middle-aged mice: relevance to autonomic nervous function.

    PubMed

    Kuwahara, Masayoshi; Ito, Koichi; Hayakawa, Koji; Yagi, Shintaro; Shiota, Kunio

    2015-01-01

    Aging is associated with a variety of physiological changes originating peripherally and centrally, including within the autonomic nervous system. Sleep-wake disturbances constitute reliable hallmarks of aging in several animal species and humans. Recent studies have been interested in N-acetylmannosamine (ManNAc) a potential therapeutic agent for improving quality of life, as well as preventing age-related cognitive decline. In this study, ManNAc (5.0 mg/ml) was administered in the drinking water of middle-aged male C57BL/6J mice (55 weeks old) for 7 days. Mice were housed under a 12:12 h light:dark cycle at 23-24 °C. We evaluated bio-behavioral activity using electrocardiogram, body temperature and locomotor activity recorded by an implanted telemetry transmitter. To estimate sleep-wake profile, surface electroencephalogram and electromyogram leads connected to a telemetry transmitter were also implanted in mice. Autonomic nervous activity was evaluated using power spectral analysis of heart rate variability. ManNAc-treated mice spent more time in a wakeful state and less time in slow wave sleep during the dark phase. Parasympathetic nervous activity was increased following ManNAc treatment, then the sympatho-vagal balance was shifted predominance of parasympathetic nervous system. Furthermore, improvement in sleep-wake pattern was associated with increased parasympathetic nervous activity. These results suggest that ManNAc treatment can improve bio-behavioral activity and sleep-wake quality in middle-aged mice. This may have implications for improving sleep patterns in elderly humans. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Use of Global Positioning Systems to Study Physical Activity and the Environment

    PubMed Central

    Krenn, Patricia J; Titze, Sylvia; Oja, Pekka; Jones, Andrew; Ogilvie, David

    2013-01-01

    Context The Global Positioning System (GPS) represents an innovative way to objectively assess the spatial locations of physical activity behavior. Purpose The aim of this systematic review was to determine the capability of GPS to collect high quality data on the location of activities in research on the relationship between physical activity and the environment. Evidence acquisition Published and unpublished articles identified from seven electronic databases, reference lists, bibliographies and websites up to March 2010 were systematically searched for, appraised and analysed in summer 2010. Included studies used GPS to measure the spatial locations of physical activity and some form of environmental analysis related to the GPS data. The capability of GPS was expressed in terms of data quality which in turn was defined as the proportion of GPS data lost in each study. Evidence synthesis 24 studies met the inclusion criteria. Data loss was positively correlated with the measurement period for which participants were asked to wear the GPS device (r=0.81, p<0.001). Major reasons for data loss included signal drop outs, loss of device battery power, and poor adherence of participants to measurement protocols. Data loss did not differ significantly between children and adults or by study sample size, year of publication or GPS device manufacturer. Conclusions GPS is a promising tool for improving our understanding of the spatial context of physical activity. Our findings suggest that the choice of an appropriate device and efforts to maximise participant adherence are key improving data quality, especially over longer study periods. PMID:22011423

  8. Early and Later Life Stress Alter Brain Activity and Sleep in Rats

    PubMed Central

    Mrdalj, Jelena; Pallesen, Ståle; Milde, Anne Marita; Jellestad, Finn Konow; Murison, Robert; Ursin, Reidun; Bjorvatn, Bjørn; Grønli, Janne

    2013-01-01

    Exposure to early life stress may profoundly influence the developing brain in lasting ways. Neuropsychiatric disorders associated with early life adversity may involve neural changes reflected in EEG power as a measure of brain activity and disturbed sleep. The main aim of the present study was for the first time to characterize possible changes in adult EEG power after postnatal maternal separation in rats. Furthermore, in the same animals, we investigated how EEG power and sleep architecture were affected after exposure to a chronic mild stress protocol. During postnatal day 2–14 male rats were exposed to either long maternal separation (180 min) or brief maternal separation (10 min). Long maternally separated offspring showed a sleep-wake nonspecific reduction in adult EEG power at the frontal EEG derivation compared to the brief maternally separated group. The quality of slow wave sleep differed as the long maternally separated group showed lower delta power in the frontal-frontal EEG and a slower reduction of the sleep pressure. Exposure to chronic mild stress led to a lower EEG power in both groups. Chronic exposure to mild stressors affected sleep differently in the two groups of maternal separation. Long maternally separated offspring showed more total sleep time, more episodes of rapid eye movement sleep and higher percentage of non-rapid eye movement episodes ending in rapid eye movement sleep compared to brief maternal separation. Chronic stress affected similarly other sleep parameters and flattened the sleep homeostasis curves in all offspring. The results confirm that early environmental conditions modulate the brain functioning in a long-lasting way. PMID:23922857

  9. High power diode pumped solid state (DPSS) laser systems active media robust modeling and analysis

    NASA Astrophysics Data System (ADS)

    Kashef, Tamer M.; Mokhtar, Ayman M.; Ghoniemy, Samy A.

    2018-02-01

    Diode side-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency and reliability. This paper summarizes the results of simulation of the most predominant active media that are used in high power diode pumped solid-state (DPSS) laser systems. Nd:YAG, Nd:glass, and Nd:YLF rods laser systems were simulated using the special finite element analysis software program LASCAD. A performance trade off analysis for Nd:YAG, Nd:glass, and Nd:YLF rods was performed in order to predict the system optimized parameters and to investigate thermally induced thermal fracture that may occur due to heat load and mechanical stress. The simulation results showed that at the optimized values Nd:YAG rod achieved the highest output power of 175W with 43% efficiency and heat load of 1.873W/mm3. A negligible changes in laser output power, heat load, stress, and temperature distributions were observed when the Nd:YAG rod length was increased from 72 to 80mm. Simulation of Nd:glass at different rod diameters at the same pumping conditions showed better results for mechanical stress and thermal load than that of Nd:YAG and Nd:YLF which makes it very suitable for high power laser applications especially for large rod diameters. For large rod diameters Nd:YLF is mechanically weaker and softer crystal compared to Nd:YAG and Nd:glass due to its poor thermomechanical properties which limits its usage to only low to medium power systems.

  10. To the theory of high-power gyrotrons with uptapered resonators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dumbrajs, O.; Nusinovich, G. S.

    In high-power gyrotrons it is desirable to combine an optimal resonator length with the optimal value of the resonator quality factor. In resonators with the constant radius of the central part, the possibilities of this combination are limited because the quality factor of the resonator sharply increases with its length. Therefore the attempts to increase the length for maximizing the efficiency leads to such increase in the quality factor which makes the optimal current too small. Resonators with slightly uptapered profiles offer more flexibility in this regard. In such resonators, one can separate optimization of the interaction length from optimizationmore » of the quality factor because the quality factor determined by diffractive losses can be reduced by increasing the angle of uptapering. In the present paper, these issues are analyzed by studying as a typical high-power 17 GHz gyrotron which is currently under development in Europe for ITER (http://en.wikipedia.org/wiki/ITER). The effect of a slight uptapering of the resonator wall on the efficiency enhancement and the purity of the radiation spectrum in the process of the gyrotron start-up and power modulation are studied. Results show that optimal modification of the shape of a slightly uptapered resonator may result in increasing the gyrotron power from 1052 to 1360 kW.« less

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

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

    Data on the comparative analysis variants of the quality of power installations (benchmarking) applied in the power industry is systematized. It is shown that the most efficient variant of implementation of the benchmarking technique is the analysis of statistical distributions of the indicators in the composed homogenous group of the uniform power installations. The benchmarking technique aimed at revealing the available reserves on improvement of the reliability and heat efficiency indicators of the power installations of the thermal power plants is developed in the furtherance of this approach. The technique provides a possibility of reliable comparison of the quality of the power installations in their homogenous group limited by the number and adoption of the adequate decision on improving some or other technical characteristics of this power installation. The technique provides structuring of the list of the comparison indicators and internal factors affecting them represented according to the requirements of the sectoral standards and taking into account the price formation characteristics in the Russian power industry. The mentioned structuring ensures traceability of the reasons of deviation of the internal influencing factors from the specified values. The starting point for further detail analysis of the delay of the certain power installation indicators from the best practice expressed in the specific money equivalent is positioning of this power installation on distribution of the key indicator being a convolution of the comparison indicators. The distribution of the key indicator is simulated by the Monte-Carlo method after receiving the actual distributions of the comparison indicators: specific lost profit due to the short supply of electric energy and short delivery of power, specific cost of losses due to the nonoptimal expenditures for repairs, and specific cost of excess fuel equivalent consumption. The quality loss indicators are developed facilitating the analysis of the benchmarking results permitting to represent the quality loss of this power installation in the form of the difference between the actual value of the key indicator or comparison indicator and the best quartile of the existing distribution. The uncertainty of the obtained values of the quality loss indicators was evaluated by transforming the standard uncertainties of the input values into the expanded uncertainties of the output values with the confidence level of 95%. The efficiency of the technique is demonstrated in terms of benchmarking of the main thermal and mechanical equipment of the extraction power-generating units T-250 and power installations of the thermal power plants with the main steam pressure 130 atm.

  12. Effects of thermal treatment and sonication on quality attributes of Chokanan mango (Mangifera indica L.) juice.

    PubMed

    Santhirasegaram, Vicknesha; Razali, Zuliana; Somasundram, Chandran

    2013-09-01

    Ultrasonic treatment is an emerging food processing technology that has growing interest among health-conscious consumers. Freshly squeezed Chokanan mango juice was thermally treated (at 90 °C for 30 and 60s) and sonicated (for 15, 30 and 60 min at 25 °C, 40 kHz frequency, 130 W) to compare the effect on microbial inactivation, physicochemical properties, antioxidant activities and other quality parameters. After sonication and thermal treatment, no significant changes occurred in pH, total soluble solids and titratable acidity. Sonication for 15 and 30 min showed significant improvement in selected quality parameters except color and ascorbic acid content, when compared to freshly squeezed juice (control). A significant increase in extractability of carotenoids (4-9%) and polyphenols (30-35%) was observed for juice subjected to ultrasonic treatment for 15 and 30 min, when compared to the control. In addition, enhancement of radical scavenging activity and reducing power was observed in all sonicated juice samples regardless of treatment time. Thermal and ultrasonic treatment exhibited significant reduction in microbial count of the juice. The results obtained support the use of sonication to improve the quality of Chokanan mango juice along with safety standard as an alternative to thermal treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Parasympathetic reinnervation accompanied by improved post-exercise heart rate recovery and quality of life in heart transplant recipients.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro; Okada, Ikuko; Kato, Naoko; Fujino, Takeo; Inaba, Toshiro; Maki, Hisataka; Hatano, Masaru; Kinoshita, Osamu; Nawata, Kan; Kyo, Shunei; Ono, Minoru

    2015-01-01

    Although sympathetic reinnervation is accompanied by the improvement of exercise tolerability during the first years after heart transplantation (HTx), little is known about parasympathetic reinnervation and its clinical impact. We enrolled 21 recipients (40 ± 16 years, 71% male) who had received successive cardiopulmonary exercise testing at 6 months, and 1 and 2 years after HTx. Exercise parameters such as peak oxygen consumption or achieved maximum load remained unchanged, whereas recovery parameters including heart rate (HR) recovery during 2 minutes and the delay of peak HR, which are influenced by parasympathetic activity, improved significantly during post-HTx 2 years (P < 0.05 for both). HR variability was analysed at post-HTx 6 months in 18 recipients, and high frequency power, representing parasympathetic activity, was significantly associated with the 2 recovery parameters (P < 0.05 for all). We also assessed quality of life using the Minnesota Living with Heart Failure (HF) Questionnaire at post-HTx 6 months and 2 years in the same 18 recipients, and those with improved recovery parameters enjoyed a better HF-specific quality of life (P < 0.05 for both). In conclusion, parasympathetic reinnervation emerges along with improved post-exercise recovery ability of HR and quality of life during post-HTx 2 years.

  14. A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG.

    PubMed

    St John, Ashley M; Kao, Katie; Chita-Tegmark, Meia; Liederman, Jacqueline; Grieve, Philip G; Tarullo, Amanda R

    2017-05-03

    Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants socially interact. Electroencephalography (EEG) power is an advantageous technique to assess infant functional neural activation. However, many studies record infant EEG only during one baseline condition. This protocol describes a paradigm that is designed to comprehensively assess infant EEG activity in both social and nonsocial contexts as well as tease apart how different types of social inputs differentially relate to infant EEG. The within-subjects paradigm includes four controlled conditions. In the nonsocial condition, infants view objects on computer screens. The joint attention condition involves an experimenter directing the infant's attention to pictures. The joint attention condition includes three types of social input: language, face-to-face interaction, and the presence of joint attention. Differences in infant EEG between the nonsocial and joint attention conditions could be due to any of these three types of input. Therefore, two additional conditions (one with language input while the experimenter is hidden behind a screen and one with face-to-face interaction) were included to assess the driving contextual factors in patterns of infant neural activation. Representative results demonstrate that infant EEG power varied by condition, both overall and differentially by brain region, supporting the functional nature of infant EEG power. This technique is advantageous in that it includes conditions that are clearly social or nonsocial and allows for examination of how specific types of social input relate to EEG power. This paradigm can be used to assess how individual differences in age, affect, socioeconomic status, and parent-infant interaction quality relate to the development of the social brain. Based on the demonstrated functional nature of infant EEG power, future studies should consider the role of EEG recording context and design conditions that are clearly social or nonsocial.

  15. PM-1 NUCLEAR POWER PROGRAM. VOLUME II. PLANT PERFORMANCE STUDIES. Final Periodic Report, September 1, 1962 to December 31, 1962

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1963-04-01

    Data obtained during the performance testing of the PM-1 plant were compiled and evaluated. The plant powers an Air Defense Command radar station located at Sundance, Wyoming, and is required to supply extremely high-quality electrical power (minimum of frequency and voltage fluctuations) even during severe load transients. The data obtained were compiled into the following format: (1) operating requirements; (2) startup requirements; (3) plant as an energy source; (4) plant radiation levels and health physics; (5) plant instrumentation and control; (6) reactor characteristics; (7) primary system characteristics; (8) secondary system characteristics; and (9) malfunction reports. It was concluded from themore » data that the plant performance in general meets or exceeds specification. Transient and steady-state electrical fluctuations are well within specified limitations. Heat balance data for both the primary and secondary system agree reasonably well with design predictions. Radiation levels are below those anticipated. Coolant activity in the primary system is approximately at anticipated levels; secondary system coolant activity is negligible. The core life was re-estimated based on asbuilt core characteristics. A lifetime of 16.6 Mw-yr is predicted. (auth)« less

  16. Fuel cells - a new contributor to stationary power

    NASA Astrophysics Data System (ADS)

    Dufour, Angelo U.

    Stationary power generation historically started as distributed generation near the user, with the configuration of a very open market, where a lot of small competing utilities were offering electricity to the customers. At a second time it became a `monopolistic' business because of technical reasons. Big steam turbines and electric generators, allowing better efficiencies, were more conveniently installed in very large power plants, necessarily located in sites far away from where the power was needed, and the transmission losses were bounded by AC high voltage technology. The Governments were, therefore, trying to balance the power of monopolies, that were limiting the economical development of the countries, by strengthening the concept of electrical energy price public control and, alternatively, by establishing rules to allow a free flow of electricity from one region to the other, or taking direct control through ownership of big and small utilities. The most effective way of making the electric energy system competitive has proved to be the opening of a partial competition in the generation field by forcing the utilities to compare the cost of their energy, produced with new centralised plants, to the price of the available energy, coming from combined heat and power dispersed generators. In fact, with reference to this cost, all the peculiar features of large central stations and dispersed generators were taken into account, like the widespread use of natural gas, the investment risk reduction with single smaller increments of capacity, the transmission and distribution siting difficulties and high costs, the improved system reliability, and, finally, the high quality electric power. Fuel Cells are a recently become available technology for distributed electrical energy production, because they share the main typical aspects, relevant for a distributed power system, like compatibility with other modular subsystem packages, fully automation possibility, very low noise and emissions release, high efficiency both directly as fuel cell (38-55%) and in integrated cycles (50-65% with fossil fuels), delivered `power quality' and reliability. Focus is principally kept on the impact fuel cells could have on electrical grid management and control, for their voltage support and active filtering capabilities, for their response speed and for quick load connection capabilities. The cost for the moment is high, but some technology, like phosphoric acid, is in the market entry phase. Cost analysis for the main subsystems, that is fuel cell stacks, fuel processors, and power electronics and controls, indicates that the prices will be driven down to the required levels both through technology refinements and increase of production volumes. Anyhow, a new phase is beginning, where centralised power plants are facing the competition of distributed generators, like fuel cells, small gas turbines and internal combustion engines, and of other renewable energy generators, like photovoltaics and wind generators. They all are modular, dispersed throughout the utility distribution system to provide power closer to end user, and are not in competition with existing transmission and distribution systems, but they improve the systems' utilisation. The plants will initially be directly owned and operated by gas or energy distributors, and the customers could easily supersede their mistrusts by only paying for the energy they are really utilising, leaving away the worries about the investment costs and the risks of a bad operation. An `intelligent grid', delivering high quality electrical energy to millions of electrical household consumers, which, a second later, become non-polluting energy producers, appears to be giving a very relevant contribution to `the town of the future', envisaged also by the European Commission, where the quality of our lives is mainly depending on the quality of the energy.

  17. Data quality can make or break a research infrastructure

    NASA Astrophysics Data System (ADS)

    Pastorello, G.; Gunter, D.; Chu, H.; Christianson, D. S.; Trotta, C.; Canfora, E.; Faybishenko, B.; Cheah, Y. W.; Beekwilder, N.; Chan, S.; Dengel, S.; Keenan, T. F.; O'Brien, F.; Elbashandy, A.; Poindexter, C.; Humphrey, M.; Papale, D.; Agarwal, D.

    2017-12-01

    Research infrastructures (RIs) commonly support observational data provided by multiple, independent sources. Uniformity in the data distributed by such RIs is important in most applications, e.g., in comparative studies using data from two or more sources. Achieving uniformity in terms of data quality is challenging, especially considering that many data issues are unpredictable and cannot be detected until a first occurrence of the issue. With that, many data quality control activities within RIs require a manual, human-in-the-loop element, making it an expensive activity. Our motivating example is the FLUXNET2015 dataset - a collection of ecosystem-level carbon, water, and energy fluxes between land and atmosphere from over 200 sites around the world, some sites with over 20 years of data. About 90% of the human effort to create the dataset was spent in data quality related activities. Based on this experience, we have been working on solutions to increase the automation of data quality control procedures. Since it is nearly impossible to fully automate all quality related checks, we have been drawing from the experience with techniques used in software development, which shares a few common constraints. In both managing scientific data and writing software, human time is a precious resource; code bases, as Science datasets, can be large, complex, and full of errors; both scientific and software endeavors can be pursued by individuals, but collaborative teams can accomplish a lot more. The lucrative and fast-paced nature of the software industry fueled the creation of methods and tools to increase automation and productivity within these constraints. Issue tracking systems, methods for translating problems into automated tests, powerful version control tools are a few examples. Terrestrial and aquatic ecosystems research relies heavily on many types of observational data. As volumes of data collection increases, ensuring data quality is becoming an unwieldy challenge for RIs. Business as usual approaches to data quality do not work with larger data volumes. We believe RIs can benefit greatly from adapting and imitating this body of theory and practice from software quality into data quality, enabling systematic and reproducible safeguards against errors and mistakes in datasets as much as in software.

  18. How can activity-based costing methodology be performed as a powerful tool to calculate costs and secure appropriate patient care?

    PubMed

    Lin, Blossom Yen-Ju; Chao, Te-Hsin; Yao, Yuh; Tu, Shu-Min; Wu, Chun-Ching; Chern, Jin-Yuan; Chao, Shiu-Hsiung; Shaw, Keh-Yuong

    2007-04-01

    Previous studies have shown the advantages of using activity-based costing (ABC) methodology in the health care industry. The potential values of ABC methodology in health care are derived from the more accurate cost calculation compared to the traditional step-down costing, and the potentials to evaluate quality or effectiveness of health care based on health care activities. This project used ABC methodology to profile the cost structure of inpatients with surgical procedures at the Department of Colorectal Surgery in a public teaching hospital, and to identify the missing or inappropriate clinical procedures. We found that ABC methodology was able to accurately calculate costs and to identify several missing pre- and post-surgical nursing education activities in the course of treatment.

  19. Research on the effects of wind power grid to the distribution network of Henan province

    NASA Astrophysics Data System (ADS)

    Liu, Yunfeng; Zhang, Jian

    2018-04-01

    With the draining of traditional energy, all parts of nation implement policies to develop new energy to generate electricity under the favorable national policy. The wind has no pollution, Renewable and other advantages. It has become the most popular energy among the new energy power generation. The development of wind power in Henan province started relatively late, but the speed of the development is fast. The wind power of Henan province has broad development prospects. Wind power has the characteristics of volatility and randomness. The wind power access to power grids will cause much influence on the power stability and the power quality of distribution network, and some areas have appeared abandon the wind phenomenon. So the study of wind power access to power grids and find out improvement measures is very urgent. Energy storage has the properties of the space transfer energy can stabilize the operation of power grid and improve the power quality.

  20. Air quality impact of the coal-fired power plants in the northern passageway of the China West-East Power Transmission Project.

    PubMed

    Xue, Zhigang; Hao, Jiming; Chai, Fahe; Duan, Ning; Chen, Yizhen; Li, Jindan; Chen, Fu; Liu, Simei; Pu, Wenqing

    2005-12-01

    This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.

  1. Phenolic Compounds and Antioxidant Activity of Different Organs of Potentilla fruticosa L. from Two Main Production Areas of China.

    PubMed

    Yu, Danmeng; Pu, Wenjun; Li, Dengwu; Wang, Dongmei; Liu, Qiaoxiao; Wang, Yongtao

    2016-09-01

    This report compared the phenolic compounds and antioxidant activity of the leaves, flowers, and stems of Potentilla fruticosa L. collected from two main production areas of P. R. China (Taibai Mountains and the Qinghai Huzhu Northern Mountains). The results indicated that there were significant differences in the phenol contents and antioxidant activities among the different organs and between the two productions. High-performance liquid-chromatography analysis indicated that hyperoside, (+)-catechin, ellagic acid, and rutin were the primary compounds in leaves and flowers; for stems, the content of six phenolic compounds, from two productions, were the lowest. The 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) di-ammonium salt (ABTS), ferric reducing power (FRAP), lipid peroxidation assays, and microbial test system (MTS) were used to evaluate the antioxidant activity. The results demonstrated that the leaves from two productions exhibited powerful antioxidant activity than other organs, which did not significantly differ from that of the positive control (rutin), followed by the flowers and stems. The correlation between the content of phytochemicals and the antioxidant activities of different organs showed that the total phenol, tannin, hyperoside, and (+)-catechin contents may influence the antioxidant activity, and these compounds can be used as markers for the quality control of P. fruticosa. © 2016 Wiley-VHCA AG, Zürich.

  2. Novel packaging for CW and QCW diode laser modules for operation with high power and duty cycles

    NASA Astrophysics Data System (ADS)

    Fassbender, Wilhelm; Lotz, Jens; Kissel, Heiko; Biesenbach, Jens

    2018-02-01

    Continuous wave (CW) and quasi-continuous wave (QCW) operated diode laser bars and arrays have found a wide range of industrial, medical, scientific, military and space applications with a broad variety in wavelength, pulse energy, pulse duration and beam quality. Recent applications require even higher power, duty cycles and power density. The heat loss will be dissipated by conductive cooling or liquid cooling close to the bars. We present the latest performance and reliability data of two novel high-brightness CW and QCW arrays of customized and mass-production modules, in compact and robust industry design for operation with high power and high duty cycles. All designs are based on single diode packages consisting of 10mm laser bars, soft or hard soldered between expansion matched submounts. The modular components cover a wide span of designs which differ basically in water/conduction (active/passive) cooled, single, linear (horizontal and vertical) arranged designs, as well as housed and unhoused modules. The different assembling technologies of active and passive cooled base plates affect the heat dissipation and therefore the reachable power at different QCW operating conditions, as well as the lifetime. As an example, a package consisting of 8 laser diodes, connected to a 28.8*13.5*7.0mm3 DCB (direct copper bonded) submount, passively or actively cooled is considered. This design is of particular interest for mobile applications seamless module to module building system, with an infinite number of laser bars at 1.7mm pitch. Using 940nm bars we can reach an optical output power per bar of 450W at 25°C base plate temperature with 10Hz, 1.2% duty cycle and 1.2ms pulse duration. As an additional example, micro channel coolers can be vertically stacked up to 50 diodes with a 1,15mm pitch. This design is suitable for all applications, demanding also compactness and light weight and high power density. Using near infrared bars and others, we can reach an optical output power of 250W per bar at 25°C coolant temperature at CW operation.

  3. Improved cross-calibration of Thomson scattering and electron cyclotron emission with ECH on DIII-D

    DOE PAGES

    Brookman, M. W.; Austin, M. E.; McLean, A. G.; ...

    2016-08-08

    Thomson scattering (TS) produces n e profiles from measurement of scattered laser beam intensity. In the case of Rayleigh scattering, it provides a first calibration of the relation n e / ITS, which depends on many factors (e.g. laser alignment and power, optics, and measurement systems). On DIII-D, the n e calibration is adjusted for each laser and optic path against an absolute n e measurement from a density-driven cutoff on the 48 channel 2nd harmonic X-mode electron cyclotron emission (ECE) system. This method has been used to calibrate Thompson densities from the edge to near the core (r/a >more » 0.15). Application of core electron cyclotron heating improves the quality of cutoff and depth of its penetration into the core. ECH also changes underlying MHD activity. Furthermore, on the removal of ECH power, cutoff penetrates in from the edge to the core and channels fall successively and smoothly into cutoff. This improves the quality of the TS n e calibration while minimizing wall loading.« less

  4. Investigation of stability, consistency, and oil oxidation of emulsion filled gel prepared by inulin and rice bran oil using ultrasonic radiation.

    PubMed

    Nourbehesht, Newsha; Shekarchizadeh, Hajar; Soltanizadeh, Nafiseh

    2018-04-01

    Inulin, rice bran oil and rosemary essential oil were used to produce high quality emulsion filled gel (EFG) using ultrasonic radiation. Response surface methodology was used to investigate the effects of oil content, inulin content and power of ultrasound on the stability and consistency of prepared EFG. The process conditions were optimized by conducting experiments at five different levels. Second order polynomial response surface equations were developed indicating the effect of variables on EFG stability and consistency. The oil content of 18%; inulin content of 44.6%; and power of ultrasound of 256 W were found to be the optimum conditions to achieve the best EFG stability and consistency. Microstructure and rheological properties of prepared EFG were investigated. Oil oxidation as a result of using ultrasonic radiation was also investigated. The increase of oxidation products and the decrease of total phenolic compounds as well as radical scavenging activity of antioxidant compounds showed the damaging effect of ultrasound on the oil quality of EFG. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Video streaming in nursing education: bringing life to online education.

    PubMed

    Smith-Stoner, Marilyn; Willer, Ann

    2003-01-01

    Distance education is a standard form of instruction for many colleges of nursing. Web-based course and program content has been delivered primarily through text-based presentations such as PowerPoint slides and Web search activities. However, the rapid pace of technological innovation is making available more sophisticated forms of delivery such as video streaming. High-quality video streams, created at the instructor's desktop or in basic recording studios, can be produced that build on PowerPoint or create new media for use on the Web. The technology required to design, produce, and upload short video-streamed course content objects to the Internet is described. The preparation of materials, suggested production guidelines, and examples of information presented via desktop video methods are presented.

  6. Chromatographic and electrophoretic methods for Lingzhi pharmacologically active components.

    PubMed

    Huie, Carmen W; Di, Xin

    2004-12-05

    Lingzhi is the Chinese name given to the Ganoderma family of mushrooms, which was considered the most valuable medicine in ancient China and was believed to bring longevity, due to its mysterious power of healing the body and calming the mind. Today, Lingzhi is still widely revered as a valuable health supplement and herbal medicine worldwide, as studies (mostly conducted in China, Korea, Japan and the United States) into the medicinal and nutritional values of Lingzhi revealed that it does indeed contain certain bioactive ingredients (such as triterpenes and polysaccharides) that might be beneficial for the prevention and treatment of a variety of ailments, including important diseases such as hypertension, diabetes, hepatitis, cancers, and AIDS. As research into the biological activities of Lingzhi, as well as the quality assurance and quality control of Lingzhi products, require the isolation/purification of active ingredients from Lingzhi, followed by subsequent analytical and/or preparative separations, the present review summarizes the various chromatographic and electrophoretic methods (as well as sample pretreatment methods) typically employed to achieve such extraction/separation procedures.

  7. Power Quality Improvement in Induction Furnace by Harmonic Reduction Using Dynamic Voltage Restorer

    NASA Astrophysics Data System (ADS)

    Saggu, Tejinder Singh; Singh, Lakhwinder

    2016-06-01

    Induction furnaces are used in wide quantity under different capacities for annual production of around 25 million tons of iron and steel in India. It plays a vital role in various manufacturing processes around the world for melting different types of metal scraps i. e. Copper, Cast Iron, Aluminium, Steel, Brass, Bronze, Silicon, Gold, Silver etc. which are further used in many other industrial applications. The induction furnace causes a huge disturbance to the utility and nearby consumers during its operation due to its non-linear characteristics. This is a serious phenomenon responsible for power quality degradation in the power system. This paper presents methodology to improve the power quality degradation caused by induction furnace using Dynamic Voltage Restorer (DVR) which is a type of custom power device. The real time data has been taken from an industry employing induction furnace for production of ingots from scrap material. The experimental readings are measured using power quality analyser equipment. The simulation of whole plant is done by analysing this same data and the simulation results are compared with actual onsite results. Then, solution methodology using DVR is presented which revealed that the implementation of DVR is an effective solution for voltage sag mitigation and harmonics improvement in induction furnace.

  8. Quality assurance of medicines supplied to low-income and middle-income countries: poor products in shiny boxes?

    PubMed Central

    Schiavetti, B; Meessen, B; Pouget, C; Caudron, J M; Marchal, B; Massat, P; Thys, S; Ravinetto, R

    2017-01-01

    Objective In today's context of globalisation of pharmaceutical production and distribution, international and national procurement agencies play a de facto key role in defining the quality of medicines available in sub-Saharan Africa. We evaluated the compliance of a sample of pharmaceutical distributors active in sub-Saharan Africa with the standards of the WHO guideline ‘Model Quality Assurance System (WHO MQAS) for procurement agencies’, and we investigated factors favouring or hindering the adequate implementation of the guideline. Methods We used mixed-methods methodology to analyse quantitative and qualitative data. The quantitative study consisted of a retrospective secondary analysis of data collected by QUAMED (Quality Medicines for all), a partnership that pleads for universal access to quality-assured medicines. The qualitative survey consisted of formal and informal interviews with key informants. We adopted an embedded multiple-case study design. Findings Our analysis suggests that international distributors based in Europe perform, on average, better than sub-Saharan African distributors. However, some weaknesses are ubiquitous and concern critical processes, such as the initial selection of the products and the ongoing reassessment of their quality. This is due to several different factors: weak regulatory oversight, insufficient human/financial resources, weak negotiating power, limited judicial autonomy and/or lack of institutional commitment to quality. Conclusions Our findings suggest that pharmaceutical distributors active in sub-Saharan Africa generally do not apply stringent criteria for selecting products and suppliers. Therefore, product quality is not consistently assured but depends on the requirements of purchasers. While long-term solutions are awaited, the WHO MQAS guideline should be used as an evaluation and training tool to upgrade current standards. PMID:28589013

  9. The strategic defense of physician autonomy: State public health agencies as countervailing powers.

    PubMed

    Senier, Laura; Lee, Rachael; Nicoll, Lauren

    2017-08-01

    Advances in genetic testing and the aggressive marketing of genetic tests by commercial diagnostic laboratories have driven both consumer demand and the need for unbiased information about how tests should guide healthcare delivery. This paper uses the countervailing powers framework to explore the role of state public health agencies as arbiters of quality and safety, specifically through their efforts to encourage physicians to follow evidence-based recommendations for screening for hereditary cancers. Social scientists have often viewed actions by the state to regulate cost, quality, or safety as a threat to physician autonomy. This paper draws on case studies from two US states-Michigan and Connecticut-to better understand the specific role of state public health agencies, and especially whether their activities to encourage adherence to evidence-based recommendations bolster or subvert the interests of other parties in the healthcare arena. We find that lacking authority to compel provider to follow evidence-based recommendations, they improvised ways to foster compliance voluntarily, for example, by emphasizing the role of the physician as gatekeeper, thus affirming the importance of physician autonomy and clinical judgment. Both states also used public health surveillance data to make rare diseases visible and illustrate gaps between recommendations and practice. Finally, they both showed that following evidence-based recommendations could align the professional and market interests of healthcare stakeholders. Both states employed similar strategies with similar effects, despite substantial differences in the regulatory climate and organizational capacity. Taken as a whole, their activities orchestrated a countervailing response that checked the profit-seeking motives of commercial laboratories. Our findings demonstrate that rather than eroding physician autonomy, state action to monitor healthcare quality and encourage adherence to evidence-based recommendations can actually reinforce physician authority. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Music and the heart.

    PubMed

    Koelsch, Stefan; Jäncke, Lutz

    2015-11-21

    Music can powerfully evoke and modulate emotions and moods, along with changes in heart activity, blood pressure (BP), and breathing. Although there is great heterogeneity in methods and quality among previous studies on effects of music on the heart, the following findings emerge from the literature: Heart rate (HR) and respiratory rate (RR) are higher in response to exciting music compared with tranquilizing music. During musical frissons (involving shivers and piloerection), both HR and RR increase. Moreover, HR and RR tend to increase in response to music compared with silence, and HR appears to decrease in response to unpleasant music compared with pleasant music. We found no studies that would provide evidence for entrainment of HR to musical beats. Corresponding to the increase in HR, listening to exciting music (compared with tranquilizing music) is associated with a reduction of heart rate variability (HRV), including reductions of both low-frequency and high-frequency power of the HRV. Recent findings also suggest effects of music-evoked emotions on regional activity of the heart, as reflected in electrocardiogram amplitude patterns. In patients with heart disease (similar to other patient groups), music can reduce pain and anxiety, associated with lower HR and lower BP. In general, effects of music on the heart are small, and there is great inhomogeneity among studies with regard to methods, findings, and quality. Therefore, there is urgent need for systematic high-quality research on the effects of music on the heart, and on the beneficial effects of music in clinical settings. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  11. Wavelength stabilized high pulse power laser diodes for automotive LiDAR

    NASA Astrophysics Data System (ADS)

    Knigge, A.; Klehr, A.; Wenzel, H.; Zeghuzi, A.; Fricke, J.; Maaßdorf, A.; Liero, A.; Tränkle, G.

    2018-03-01

    Diode lasers generating optical pulses with high peak power and lengths in the nanosecond range are key components of systems for free-space communication, metrology, material processing, spectroscopy, and light detection and ranging (LiDAR) as needed for object detection and autonomous driving. Automotive LiDAR systems demand additionally a good beam quality and low wavelength shift with temperature due to the wide operating temperature span. We present here internally wavelength stabilized lasers emitting ns optical pulses from an emission aperture between 30 μm and 100 μm with peak powers of tens of Watts at wavelengths around 905 nm. The vertical structure based on AlGaAs (confinement and cladding layers) and InGaAs (active quantum well) is especially optimized for pulsed operation with respect to the implementation of a surface Bragg grating with a high reflectivity. The fabricated 6 mm long distributed Bragg reflector (DBR) broad area (BA) lasers are electrically driven by an in-house developed high-speed unit generating 3 to 10 ns long nearly rectangular shaped current pulses with amplitudes of up to 250 A. Such lasers emit optical pulses with a peak power of more than 30 W at 95 A pulse current up to a temperature of 85°C with a wavelength shift as low as 65 pm/K and a lateral beam propagation factor less than 10. The influence of the lateral aperture width and the pulse length on the beam quality will be shown. A monolithic integration of 3 DBR BA lasers on a single chip whose emission can be combined into a single beam raises the output power to more than 100 W.

  12. Soviet ionospheric modification research

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duncan, L.M.; Carlson, H.C.; Djuth, F.T.

    1988-07-01

    Soviet published literature in ionospheric modification research by high-power radio waves is assessed, including an evaluation of its impact on and applications to future remote-sensing and telecommunications systems. This assessment is organized to place equal emphasis on basic research activities, designed to investigate both the natural geophysical environment and fundamental plasma physics; advanced research programs, such as those studying artificial ionization processes and oblique high-power radio propagation and practical system applications and operational limitations addressed by this research. The assessment indicates that the Soviet Union sustains high-quality theoretical and experimental research programs in ionospheric modification, with a breadth and levelmore » of effort greatly exceeding comparable Western programs. Soviet theoretical research tends to be analytical and intuitive, as compared to the Western emphasis on numerical simulation techniques. The Soviet experimental approach is less exploratory, designed principally to confirm theoretical predictions. Although limited by inferior diagnostic capabilities, Soviet experimental facilities are more numerous, operate on a more regular basis, and transmit radio wave powers exceeding those os Western facilities. Because of its broad scope of activity, the Soviet Union is better poised to quickly exploit new technologies and system applications as they are developed. This panel has identified several key areas of Soviet research activity and emerging technology that may offer long-term opportunities for remote-sensing and telecommunications advantages. However, we have found no results that suggest imminent breakthrough discoveries in these fields.« less

  13. Casting Molding of PDCPD Material for Purpose of Car’s Power Steering Body

    NASA Astrophysics Data System (ADS)

    Grabowski, L.; Baier, A.; Sobek, M.

    2018-01-01

    The growing industry of polymer and composite materials is facing new challenges posed by the automotive industry. In this industry, traditional materials such as steel and aluminum are widely replaced with plastic materials, including polymers. In the past, such behavior concerned design and interior elements, but more and more often plastics are used in the case of load-bearing elements, i.e. those that require high strength and durability nowadays. This kind of materials are also often used in safety systems or driver assistance systems. Therefore, the aim of the activities described in this article are to carry out an innovative process of injection of cold polymeric material, PDCPD (Polidicyclopentadiene), polymerizing with the use of Metathesis reaction, which in 2005 was awarded the Nobel Prize. This injection applies to the worm gear components of the system, supports the power steering system of the passenger car. Also the process of selecting the appropriate parameters to carry out this process, guaranteeing the best quality of the obtained elements is necessary. The aim of the activities was to achieve a fully useful power steering support system, using a polymer body, which is replacing the aluminum. These activities were aimed at reducing the costs and weight of the final product. The injection process and the way to achieve the finished product were carried out in an innovative way, never used in industry before.

  14. Beam quality improvement by population-dynamic-coupled combined guiding effect in end-pumped Nd:YVO4 laser oscillator

    NASA Astrophysics Data System (ADS)

    Shen, Yijie; Gong, Mali; Fu, Xing

    2018-05-01

    Beam quality improvement with pump power increasing in an end-pumped laser oscillator is experimentally realized for the first time, to the best of our knowledge. The phenomenon is caused by the population-dynamic-coupled combined guiding effect, a comprehensive theoretical model of which has been well established, in agreement with the experimental results. Based on an 888 nm in-band dual-end-pumped oscillator using four tandem Nd:YVO4 crystals, the output beam quality of M^2= 1.1/1.1 at the pump power of 25 W is degraded to M^2 = 2.5/1.8 at 75 W pumping and then improved to M^2= 1.8/1.3 at 150 W pumping. The near-TEM_{00} mode is obtained with the highest continuous-wave output power of 72.1 W and the optical-to-optical efficiency of 48.1%. This work demonstrates great potential to further scale the output power of end-pumped laser oscillator while keeping good beam quality.

  15. Environmental review of Potomac Electric Power Company's proposed Station H Element I

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-04-01

    The report has been conducted to evaluate the potential impacts to environmental and cultural resources from the proposed construction and operation of Element I (the combustion turbine portion) of the Station H power plant facility at Potomac Electric Power Company's Dickerson site. This review also presents an evaluation of air quality impacts of Elements I and II (combustion turbine and combined cycle components of the facility) and an assessment of compliance with state and Federal air quality regulations (primarily the ambient air quality standards and the air quality impact requirements of PSD regulations). Results of the Environmental Review analysis aremore » used as the basis for establishing preliminary recommended licensing conditions for operating the proposed facility. These recommendations are also included in the report.« less

  16. Daytime Ayahuasca administration modulates REM and slow-wave sleep in healthy volunteers.

    PubMed

    Barbanoj, Manel J; Riba, Jordi; Clos, S; Giménez, S; Grasa, E; Romero, S

    2008-02-01

    Ayahuasca is a traditional South American psychoactive beverage and the central sacrament of Brazilian-based religious groups, with followers in Europe and the United States. The tea contains the psychedelic indole N,N-dimethyltryptamine (DMT) and beta-carboline alkaloids with monoamine oxidase-inhibiting properties that render DMT orally active. DMT interacts with serotonergic neurotransmission acting as a partial agonist at 5-HT(1A) and 5-HT(2A/2C) receptor sites. Given the role played by serotonin in the regulation of the sleep/wake cycle, we investigated the effects of daytime ayahuasca consumption in sleep parameters. Subjective sleep quality, polysomnography (PSG), and spectral analysis were assessed in a group of 22 healthy male volunteers after the administration of a placebo, an ayahuasca dose equivalent to 1 mg DMT kg(-1) body weight, and 20 mg d-amphetamine, a proaminergic drug, as a positive control. Results show that ayahuasca did not induce any subjectively perceived deterioration of sleep quality or PSG-measured disruptions of sleep initiation or maintenance, in contrast with d-amphetamine, which delayed sleep initiation, disrupted sleep maintenance, induced a predominance of 'light' vs 'deep' sleep and significantly impaired subjective sleep quality. PSG analysis also showed that similarly to d-amphetamine, ayahuasca inhibits rapid eye movement (REM) sleep, decreasing its duration, both in absolute values and as a percentage of total sleep time, and shows a trend increase in its onset latency. Spectral analysis showed that d-amphetamine and ayahuasca increased power in the high frequency range, mainly during stage 2. Remarkably, whereas slow-wave sleep (SWS) power in the first night cycle, an indicator of sleep pressure, was decreased by d-amphetamine, ayahuasca enhanced power in this frequency band. Results show that daytime serotonergic psychedelic drug administration leads to measurable changes in PSG and sleep power spectrum and suggest an interaction between these drugs and brain circuits modulating REM and SWS.

  17. What do Canadian seniors say supports their quality of life? Findings from a national participatory research study.

    PubMed

    Bryant, Toba; Brown, Ivan; Cogan, Tara; Dallaire, Clemence; Laforest, Sophie; McGowan, Patrick; Raphael, Dennis; Richard, Lucie; Thompson, Loraine; Young, Joyce

    2004-01-01

    A national project investigated seniors' perceptions of the influences upon their quality of life. The seven participating cities were Montreal, Quebec City, Ottawa, Toronto, Regina, Vancouver and Whitehorse. The project focussed on policy decisions affecting the quality of life of seniors. It was a participatory study in which seniors controlled the direction and shape of the project in each city. Focus groups and individual interviews with seniors and stakeholders. Data analysis used qualitative methods to see the world through the eyes of participants. Each project was committed to hearing the voices of seniors and their views on which issues were affecting the quality of their lives. Across the seven cities, seniors highlighted access to information, health care, housing, income security, safety and security, social contacts and networks, and transportation as key issues that affect the quality of life of seniors in Canada. The findings affirm the value of participatory activities that involve seniors working with other sectors as a productive policy-informing approach. The Seniors' Quality of Life projects demonstrate the conceptual power of the determinants of health perspective to understand seniors' quality of life issues. While seniors considered health care to be a continuing concern, they also recognized socio-economic issues as significantly affecting the quality of their lives.

  18. Antioxidant power as biochemical endpoint in bread for screening and early managing quality and toxicant-related safety anomalies in food production.

    PubMed

    Dragone, Roberto; Ermilov, Laura; Grasso, Gerardo; Maggioni, Silvia; Mantovani, Alberto; Frazzoli, Chiara

    2016-08-01

    Flaxseeds are both a food ingredient and a natural source of antioxidants (e.g. lignans, PUFAs) and pro-oxidant contaminants (e.g. cadmium): the variable mixture of anti- and pro-oxidant substances may impact on the redox homeostasis of flaxseed-enriched foods. The antioxidant power is studied here as biochemical activity of flaxseeds in white wheat bread and as endpoint for possible screening of anomalous variations of bioactive mixtures (antioxidants vs. prooxidants) in food matrices. A bioprobe assay based on the superoxide dismutase (SOD) enzyme (6 channels of the multiprobe bioelectronic platform BEST) was performed on white wheat bread with and without flaxseeds. Nine BEST channels were simultaneously used for validation and monitoring of measuring conditions (temperature, pH, conductivity). Findings were compared with quantitative analysis of antioxidants and pro-oxidant contaminants. Organic and aqueous extracts of both bread types were examined in parallel. The SOD-probe detected the difference in antioxidant power given by 10% flaxseed, thus supporting the use of antioxidant power detected by bioenzymatic screening as sensitive biochemical endpoint. Mixtures of bioactive molecules in foods generate biochemical activities that can be monitored as time-effective indicators of invariability, which is pivotal in the daily control of anomalies in food production and therefore in the protection of consumers' health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. The power metric: a new statistically robust enrichment-type metric for virtual screening applications with early recovery capability.

    PubMed

    Lopes, Julio Cesar Dias; Dos Santos, Fábio Mendes; Martins-José, Andrelly; Augustyns, Koen; De Winter, Hans

    2017-01-01

    A new metric for the evaluation of model performance in the field of virtual screening and quantitative structure-activity relationship applications is described. This metric has been termed the power metric and is defined as the fraction of the true positive rate divided by the sum of the true positive and false positive rates, for a given cutoff threshold. The performance of this metric is compared with alternative metrics such as the enrichment factor, the relative enrichment factor, the receiver operating curve enrichment factor, the correct classification rate, Matthews correlation coefficient and Cohen's kappa coefficient. The performance of this new metric is found to be quite robust with respect to variations in the applied cutoff threshold and ratio of the number of active compounds to the total number of compounds, and at the same time being sensitive to variations in model quality. It possesses the correct characteristics for its application in early-recognition virtual screening problems.

  20. Power quality control of an autonomous wind-diesel power system based on hybrid intelligent controller.

    PubMed

    Ko, Hee-Sang; Lee, Kwang Y; Kang, Min-Jae; Kim, Ho-Chan

    2008-12-01

    Wind power generation is gaining popularity as the power industry in the world is moving toward more liberalized trade of energy along with public concerns of more environmentally friendly mode of electricity generation. The weakness of wind power generation is its dependence on nature-the power output varies in quite a wide range due to the change of wind speed, which is difficult to model and predict. The excess fluctuation of power output and voltages can influence negatively the quality of electricity in the distribution system connected to the wind power generation plant. In this paper, the authors propose an intelligent adaptive system to control the output of a wind power generation plant to maintain the quality of electricity in the distribution system. The target wind generator is a cost-effective induction generator, while the plant is equipped with a small capacity energy storage based on conventional batteries, heater load for co-generation and braking, and a voltage smoothing device such as a static Var compensator (SVC). Fuzzy logic controller provides a flexible controller covering a wide range of energy/voltage compensation. A neural network inverse model is designed to provide compensating control amount for a system. The system can be optimized to cope with the fluctuating market-based electricity price conditions to lower the cost of electricity consumption or to maximize the power sales opportunities from the wind generation plant.

  1. Effect of Residence in Temporary Housing After the Great East Japan Earthquake on the Physical Activity and Quality of Life of Older Survivors.

    PubMed

    Moriyama, Nobuaki; Urabe, Yukio; Onoda, Shuichi; Maeda, Noriaki; Oikawa, Tomoyoshi

    2017-12-01

    This study aimed to compare the physical activity level and health-related quality of life (HRQOL) between older survivors residing in temporary housing after the Great East Japan Earthquake (GEJE; temporary housing group) and older individuals residing in their own homes (control group) and to clarify whether mobility function and muscle strength were correlated with physical activity among older temporary housing residents. Subjects were recruited to the temporary housing group (n=64, 19 men and 45 women) or control group (n=64, 33 men and 31 women) according to their residence. Physical activity was assessed by the number of walking steps determined by using a triaxial accelerometer, mobility function by the Timed Up and Go test, muscle strength by the grasping power test, and HRQOL by the Medical Outcome Study 36-Item Short Form Survey v2. In the temporary housing group, reduced physical activity and correlation between physical activity and mobility function in men, and muscle strength in both men and women, were observed. There was no significant difference in HRQOL between groups except for bodily pain in women. Support for older evacuees should focus on maintaining their physical activity level as well as on HRQOL to avoid deterioration of health in these survivors. (Disaster Med Public Health Preparedness. 2017;11:701-710).

  2. Recent Trend of New Type Power Delivery System and its Demonstrative Project in Japan

    NASA Astrophysics Data System (ADS)

    Morozumi, Satoshi; Nara, Koichi

    Recently many such distributed generating systems as co-generation, photovoltaic, wind, fuel cells etc. are introduced into power distribution system, and the power system must cope with the situation with distributed generators. Moreover, such industries as IT request reliable and high quality power to preserve their businesses, and some other electric energy based industries request less reliable but cheaper electricity. From these backgrounds, several new type power delivery systems are emerging where lots of distributed generators (DGs) can be connected and many benefits offered by DGs can be realized without affecting the existing power system. They are referred to various names. In U.S.A., Microgrid, Power Park and Virtual Utilities, etc. are proposed. In Europe, DISPOWER or Smart Grid is under developing. In Japan, FRIENDS and Demand Area Network System etc. are proposed and tested in real sites. In this paper, first, general concepts of such new type power delivery systems and new businesses expected to be created by using DGs are introduced. Then, recent research activities in this area in Japan are introduced so as to stimulate new business opportunities. In the later part of this paper, related NEDO's demonstrative projects are introduced. NEDO is the largest public R&D management organization and promoting several projects regarding grid connecting issues on the power system. Those projects were planned to solve several problems on the power system where distributed renewable energy resources are installed.

  3. Quality Assurance in Higher Education: Reflection, Criticism, and Change

    ERIC Educational Resources Information Center

    Yingqiang, Zhang; Yongjian, Su

    2016-01-01

    Quality assurance in modern higher education is both an accountability-oriented ideology and a technological method. It has also evolved into a increasingly rationalist and professionalized power mechanism. Its advocacy of compliance, technological mythology, and imbalance between power and responsibility are inherent disadvantages of higher…

  4. Predicted impact of thermal power generation emission control measures in the Beijing-Tianjin-Hebei region on air pollution over Beijing, China.

    PubMed

    Wang, Liqiang; Li, Pengfei; Yu, Shaocai; Mehmood, Khalid; Li, Zhen; Chang, Shucheng; Liu, Weiping; Rosenfeld, Daniel; Flagan, Richard C; Seinfeld, John H

    2018-01-17

    Widespread economic growth in China has led to increasing episodes of severe air pollution, especially in major urban areas. Thermal power plants represent a particularly important class of emissions. Here we present an evaluation of the predicted effectiveness of a series of recently proposed thermal power plant emission controls in the Beijing-Tianjin-Hebei (BTH) region on air quality over Beijing using the Community Multiscale Air Quality(CMAQ) atmospheric chemical transport model to predict CO, SO 2 , NO 2 , PM 2.5 , and PM 10 levels. A baseline simulation of the hypothetical removal of all thermal power plants in the BTH region is predicted to lead to 38%, 23%, 23%, 24%, and 24% reductions in current annual mean levels of CO, SO 2 , NO 2 , PM 2.5 , and PM 10 in Beijing, respectively. Similar percentage reductions are predicted in the major cities in the BTH region. Simulations of the air quality impact of six proposed thermal power plant emission reduction strategies over the BTH region provide an estimate of the potential improvement in air quality in the Beijing metropolitan area, as a function of the time of year.

  5. Transparency in a Pediatric Quality Improvement Collaborative: A Passionate Journey by NPC-QIC Clinicians and Parents.

    PubMed

    Lihn, Stacey L; Kugler, John D; Peterson, Laura E; Lannon, Carole M; Pickles, Diane; Beekman, Robert H

    2015-01-01

    Transparency-sharing data or information about outcomes, processes, protocols, and practices-may be the most powerful driver of health care improvement. In this special article, the development and growth of transparency within the National Pediatric Cardiology Quality Improvement Collaborative is described. The National Pediatric Cardiology Quality Improvement Collaborative transparency journey is guided by equal numbers of clinicians and parents of children with congenital heart disease working together in a Transparency Work Group. Activities are organized around four interrelated levels of transparency (individual, organizational, collaborative, and system), each with a specified purpose and aim. A number of Transparency Work Group recommendations have been operationalized. Aggregate collaborative performance is now reported on the public-facing web site. Specific information that the Transparency Work Group recommends centers provide to parents has been developed and published. Almost half of National Pediatric Cardiology Quality Improvement Collaborative centers participated in a pilot of transparently sharing their outcomes achieved with one another. Individual centers have also begun successfully implementing recommended transparency activities. Despite progress, barriers to full transparency persist, including health care organization concerns about potential negative effects of disclosure on reputation and finances, and lack of reliable definitions, data, and reporting standards for fair comparisons of centers. The National Pediatric Cardiology Quality Improvement Collaborative's transparency efforts have been a journey that continues, not a single goal or destination. Balanced participation of clinicians and parents has been a critical element of the collaborative's success on this issue. Plans are in place to guide implementation of additional transparency recommendations across all four levels, including extension of the activities beyond the collaborative to support transparency efforts in national cardiology and cardiac surgery societies. © 2015 Wiley Periodicals, Inc.

  6. Impact of physical therapy for Parkinson's disease: a critical review of the literature.

    PubMed

    Kwakkel, G; de Goede, C J T; van Wegen, E E H

    2007-01-01

    A systematic review of the literature found 23 randomized clinical trials reflecting specific core areas of physical therapy (PT), that is, transfer, posture, balance, reaching and grasping, gait, and physical condition. All studies were of moderate methodological quality. Important limitations of the studies were: (1) insufficient statistical power (type II error); (2) poor methodological quality due to inadequate randomization and blinding procedures; (3) insufficient contrast in dosage and treatment between experimental and control groups; and (4) lack of appropriate measurement instruments able to identify clinically meaningful changes according to the International Classification of Functioning (ICF). In the last 5 years, the methodological quality of RCTs has shown substantial improvement. Most high-quality studies investigated the effects of exercise therapy, including the use of external rhythms to improve gait and gait-related activities. The results of these trials suggest that the effects of PT are task- and context-specific. This indicates that the tasks that are trained tend not to generalize to related activities that are not directly trained in the rehabilitation programme itself, and suggests that future programmes should train meaningful tasks preferably in patients' home environment. In addition, the decline in treatment effects after an intervention has ended suggests the need for permanent treatment of patients with PD, i.e. chronic treatment for this chronic disease. Future studies should aim to develop responsive measurement instruments able to monitor meaningful changes in activities, as well as better understanding of insufficiently understood symptoms such as freezing, rigidity and bradykinesia and greater insight into neurophysiological mechanisms underlying training-induced changes in activities such as improved gait performance by rhythmic cueing.

  7. INTERNATIONAL CONFERENCE ON SEMICONDUCTOR INJECTION LASERS SELCO-87: Liquid phase epitaxial growth of GaInAsP/InP laser structures

    NASA Astrophysics Data System (ADS)

    Nohavica, D.; Têminová, J.; Berková, D.; Zagrádková, M.; Kortan, I.; Zelinka, I.; Walachová, I.; Malina, V.

    1988-11-01

    A modified single-phase liquid phase epitaxy method was developed on the basis of a novel variant of the growth boat. The method was used to grow GaInAsP/InP double heterostructures for lasers emitting at 1.3 and 1.55 μm. The main properties of wide-contact diodes (radiation power and threshold current density) were adopted as the characteristics of the quality of heterostructures characterized by different configurations of active and guiding layers. The quality of the structure was confirmed by the fabrication of laser diodes of the following types: stripe with oxide insulation, clad-ridge waveguide, and double-channel planar buried.

  8. Comparison of Power Versus Manual Injection in Bolus Shape and Image Quality on Contrast-Enhanced Magnetic Resonance Angiography: An Experimental Study in a Swine Model.

    PubMed

    Tsuboyama, Takahiro; Jost, Gregor; Pietsch, Hubertus; Tomiyama, Noriyuki

    2017-09-01

    The aim of this study was to compare power versus manual injection in bolus shape and image quality on contrast-enhanced magnetic resonance angiography (CE-MRA). Three types of CE-MRA (head-neck 3-dimensional [3D] MRA with a test-bolus technique, thoracic-abdominal 3D MRA with a bolus-tracking technique, and thoracic-abdominal time-resolved 4-dimensional [4D] MRA) were performed after power and manual injection of gadobutrol (0.1 mmol/kg) at 2 mL/s in 12 pigs (6 sets of power and manual injections for each type of CE-MRA). For the quantitative analysis, the signal-to-noise ratio was measured on ascending aorta, descending aorta, brachiocephalic trunk, common carotid artery, and external carotid artery on the 6 sets of head-neck 3D MRA, and on ascending aorta, descending aorta, brachiocephalic trunk, abdominal aorta, celiac trunk, and renal artery on the 6 sets of thoracic-abdominal 3D MRA. Bolus shapes were evaluated on the 6 sets each of test-bolus scans and 4D MRA. For the qualitative analysis, arterial enhancement, superimposition of nontargeted enhancement, and overall image quality were evaluated on 3D MRA. Visibility of bolus transition was assessed on 4D MRA. Intraindividual comparison between power and manual injection was made by paired t test, Wilcoxon rank sum test, and analysis of variance by ranks. Signal-to-noise ratio on 3D MRA was statistically higher with power injection than with manual injection (P < 0.001). Bolus shapes (test-bolus, 4D MRA) were represented by a characteristic standard bolus curve (sharp first-pass peak followed by a gentle recirculation peak) in all the 12 scans with power injection, but only in 1 of the 12 scans with manual injection. Standard deviations of time-to-peak enhancement were smaller in power injection than in manual injection. Qualitatively, although both injection methods achieved diagnostic quality on 3D MRA, power injection exhibited significantly higher image quality than manual injection (P = 0.001) due to significantly higher arterial enhancement (P = 0.031) and less superimposition of nontargeted enhancement (P = 0.001). Visibility of bolus transition on 4D MRA was significantly better with power injection than with manual injection (P = 0.031). Compared with manual injection, power injection provides more standardized bolus shapes and higher image quality due to higher arterial enhancement and less superimposition of nontargeted vessels.

  9. A Piloted Simulator Evaluation of Transport Aircraft Rudder Pedal Force/Feel Characteristics

    NASA Technical Reports Server (NTRS)

    Stewart, Eric C.

    2008-01-01

    A piloted simulation study has been conducted in a fixed-base research simulator to assess the directional handling qualities for various rudder pedal feel characteristics for commercial transport airplanes. That is, the effects of static pedal force at maximum pedal travel, breakout force, and maximum pedal travel on handling qualities were studied. An artificial maneuver with a severe lateral wind shear and requiring runway tracking at an altitude of 50 feet in a crosswind was used to fully exercise the rudder pedals. Twelve active airline pilots voluntarily participated in the study and flew approximately 500 maneuvers. The pilots rated the maneuver performance with various rudder pedal feel characteristics using the Cooper- Harper rating scale. The test matrix had 15 unique combinations of the 3 static pedal feel characteristics. A 10-term, second-order equation for the Cooper-Harper pilot rating as a function of the 3 independent pedal feel parameters was fit to the data. The test matrix utilized a Central Composite Design that is very efficient for fitting an equation of this form. The equation was used to produce contour plots of constant pilot ratings as a function of two of the parameters with the third parameter held constant. These contour plots showed regions of good handling qualities as well as regions of degraded handling qualities. In addition, a numerical equation solver was used to predict the optimum parameter values (those with the lowest pilot rating). Quantitative pilot performance data were also analyzed. This analysis found that the peak values of the cross power spectra of the pedal force and heading angle could be used to quantify the tendency toward directional pilot induced oscillations (PIO). Larger peak values of the cross power spectra were correlated with larger (degraded) Cooper-Harper pilot ratings. Thus, the subjective data (Cooper-Harper pilot ratings) were consistent with the objective data (peak values of the cross power spectra).

  10. Apps for People With Rheumatoid Arthritis to Monitor Their Disease Activity: A Review of Apps for Best Practice and Quality

    PubMed Central

    Townsley, Hermaleigh; White, Bonnie; Langlotz, Tobias; Taylor, William J

    2017-01-01

    Background Rheumatoid arthritis (RA) is a chronic inflammatory arthritis requiring long-term treatment with regular monitoring by a rheumatologist to achieve good health outcomes. Since people with RA may wish to monitor their own disease activity with a smartphone app, it is important to understand the functions and quality of apps for this purpose. Objective The aim of our study was to assess the features and quality of apps to assist people to monitor their RA disease activity by (1) summarizing the available apps, particularly the instruments used for measurement of RA disease activity; (2) comparing the app features with American College of Rheumatology and European League against Rheumatism (ACR and EULAR) guidelines for monitoring of RA disease activity; and (3) rating app quality with the Mobile App Rating Scale (MARS). Methods Systematic searches of the New Zealand iTunes and Google Play app stores were used to identify all apps for monitoring of RA disease activity that could be used by people with RA. The apps were described by both key metadata and app functionality. App adherence with recommendations for monitoring of RA disease activity in clinical practice was evaluated by identifying whether apps included calculation of a validated composite disease activity measure and recorded results for future retrieval. App quality was assessed by 2 independent reviewers using the MARS. Results The search identified 721 apps in the Google Play store and 216 in the iTunes store, of which 19 unique apps met criteria for inclusion (8 from both app stores, 8 iTunes, and 3 Google Play). In total, 14 apps included at least one validated instrument measuring RA disease activity; 7 of 11 apps that allowed users to enter a joint count used the standard 28 swollen and tender joint count; 8 apps included at least one ACR and EULAR-recommended RA composite disease activity (CDA) measure; and 10 apps included data storage and retrieval. Only 1 app, Arthritis Power, included both an RA CDA measure and tracked data, but this app did not include the standard 28 tender and swollen joint count. The median overall MARS score for apps was 3.41/5. Of the 6 apps that scored ≥4/5 on the overall MARS rating, only 1 included a CDA score endorsed by ACR and EULAR; however, this app did not have a data tracking function. Conclusions This review found a lack of high-quality apps for longitudinal assessment of RA disease activity. Current apps fall into two categories: simple calculators primarily for rheumatologists and data tracking tools for people with RA. The latter do not uniformly collect data using validated instruments or composite disease activity measures. There is a need for appropriate, high-quality apps for use by rheumatologists and patients together in co-management of RA. PMID:28223263

  11. Operational Results From a High Power Alternator Test Bed

    NASA Technical Reports Server (NTRS)

    Birchenough, Arthur; Hervol, David

    2007-01-01

    The Alternator Test Unit (ATU) in the Lunar Power System Facility (LPSF) located at the NASA Glenn Research Center (GRC) in Cleveland, Ohio was used to simulate the operating conditions and evaluate the performance of the ATU and its interaction with various LPSF components in accordance with the current Fission Surface Power System (FSPS) requirements. The testing was carried out at the breadboard development level. These results successfully demonstrated excellent ATU power bus characteristics and rectified user load power quality during steady state and transient conditions. Information gained from this work could be used to assist the design and primary power quality considerations for a possible future FSPS. This paper describes the LPSF components and some preliminary test results.

  12. Implementation of structured physical activity in the pediatric stem cell transplantation.

    PubMed

    Rosenhagen, A; Bernhörster, M; Vogt, L; Weiss, B; Senn, A; Arndt, S; Siegler, K; Jung, M; Bader, P; Banzer, W

    2011-05-01

    The peripheral blood stem cell transplantation (PBSCT) represents a specific, but stressful therapy for hemato-oncological diseases. While for adults, data suggest positive eff ects for a supportive sport therapy, this question is not evaluated sufficiently for children. The objective of this study was to examine the integration of sports activity into pediatric PBSCT and to indicate attainable results. This 2-step case-control-study included 23 children and adolescents from the PBSCT: During the isolation phase 13 patients trained 3 times per week on a cycle ergometer and passed a course with different sports equipment. Apart from recording physiologic adaptations, quality of live was inquired in a pre-post design using questionnaires. Guided interviews according to necessity and requirements for sports activity at the PBSCT unit completed the evaluation and were used for the intervention as well as for the control group (n = 10) without sports therapy. On the ergometer, patients trained average 25 min with 0.6 watt / kg. In the majority, a loss of muscular power could be avoided. Quality of life and fatigue symptoms improved by trend. Interview analysis showed general acceptance of physical activity during PBSCT. After initial skepticism due to the additional burden, our implementation study showed the feasibility of supportive sports therapy in PBSCT. Quality and flexibility of the equipment should be higher than normal and different physical and psychological conditions of the patients should be anticipated and integrated into the training program.

  13. Efficient Safety and Degradation Modeling of Automotive Lithium-ion Cells and Packs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Chao-Yang

    2017-09-07

    This document is intended to give an overall synopsis of the activities and accomplishments of the EC Power CAEBAT2 project over the course of four years. The reader is referred to the previously submitted quarterly reports, review presentations, and AMR presentations for further technical details. As highlighted by the numerous results shown herein and the volume and quality of the publications and presentations made in the course of this project, we feel that we have made a strong impact in the community.

  14. Optical components of adaptive systems for improving laser beam quality

    NASA Astrophysics Data System (ADS)

    Malakhov, Yuri I.; Atuchin, Victor V.; Kudryashov, Aleksis V.; Starikov, Fedor A.

    2008-10-01

    The short overview is given of optical equipment developed within the ISTC activity for adaptive systems of new generation allowing for correction of high-power laser beams carrying optical vortices onto the phase surface. They are the kinoform many-level optical elements of new generation, namely, special spiral phase plates and ordered rasters of microlenses, i.e. lenslet arrays, as well as the wide-aperture Hartmann-Shack sensors and bimorph deformable piezoceramics- based mirrors with various grids of control elements.

  15. Learning about leadership - A personal account.

    PubMed

    Cheang, P P

    2011-01-01

    A personal account of learning about leadership. This article introduces the theory of power and influence, and aimed to report especially the personal reflection, emotional intelligence and learning about oneself that occurred on the way. Reading, group discussion and active reflection. Thoughts, reflections and learning were recorded regularly. The concept of leadership, influence tactics and emotional intelligence all have implications in workplace relationship management and ultimately leadership qualities. The issues discussed serves as food for thought for others. This is a genuine and very personal learning experience.

  16. Waveguide device and method for making same

    DOEpatents

    Forman, Michael A [San Francisco, CA

    2007-08-14

    A monolithic micromachined waveguide device or devices with low-loss, high-power handling, and near-optical frequency ranges is set forth. The waveguide and integrated devices are capable of transmitting near-optical frequencies due to optical-quality sidewall roughness. The device or devices are fabricated in parallel, may be mass produced using a LIGA manufacturing process, and may include a passive component such as a diplexer and/or an active capping layer capable of particularized signal processing of the waveforms propagated by the waveguide.

  17. Phase 1 of the near term hybrid passenger vehicle development program. Appendix B: Trade-off studies, volume 1

    NASA Technical Reports Server (NTRS)

    Traversi, M.; Piccolo, R.

    1980-01-01

    Tradeoff study activities and the analysis process used are described with emphasis on (1) review of the alternatives; (2) vehicle architecture; and (3) evaluation of the propulsion system alternatives; interim results are presented for the basic hybrid vehicle characterization; vehicle scheme development; propulsion system power and transmission ratios; vehicle weight; energy consumption and emissions; performance; production costs; reliability, availability and maintainability; life cycle costs, and operational quality. The final vehicle conceptual design is examined.

  18. Control of Disturbing Loads in Residential and Commercial Buildings via Geometric Algebra

    PubMed Central

    2013-01-01

    Many definitions have been formulated to represent nonactive power for distorted voltages and currents in electronic and electrical systems. Unfortunately, no single universally suitable representation has been accepted as a prototype for this power component. This paper defines a nonactive power multivector from the most advanced multivectorial power theory based on the geometric algebra (GA). The new concept can have more importance on harmonic loads compensation, identification, and metering, between other applications. Likewise, this paper is concerned with a pioneering method for the compensation of disturbing loads. In this way, we propose a multivectorial relative quality index   δ~ associated with the power multivector. It can be assumed as a new index for power quality evaluation, harmonic sources detection, and power factor improvement in residential and commercial buildings. The proposed method consists of a single-point strategy based of a comparison among different relative quality index multivectors, which may be measured at the different loads on the same metering point. The comparison can give pieces of information with magnitude, direction, and sense on the presence of disturbing loads. A numerical example is used to illustrate the clear capabilities of the suggested approach. PMID:24260017

  19. Control of disturbing loads in residential and commercial buildings via geometric algebra.

    PubMed

    Castilla, Manuel-V

    2013-01-01

    Many definitions have been formulated to represent nonactive power for distorted voltages and currents in electronic and electrical systems. Unfortunately, no single universally suitable representation has been accepted as a prototype for this power component. This paper defines a nonactive power multivector from the most advanced multivectorial power theory based on the geometric algebra (GA). The new concept can have more importance on harmonic loads compensation, identification, and metering, between other applications. Likewise, this paper is concerned with a pioneering method for the compensation of disturbing loads. In this way, we propose a multivectorial relative quality index δ(~) associated with the power multivector. It can be assumed as a new index for power quality evaluation, harmonic sources detection, and power factor improvement in residential and commercial buildings. The proposed method consists of a single-point strategy based of a comparison among different relative quality index multivectors, which may be measured at the different loads on the same metering point. The comparison can give pieces of information with magnitude, direction, and sense on the presence of disturbing loads. A numerical example is used to illustrate the clear capabilities of the suggested approach.

  20. Multifunctional voltage source inverter for renewable energy integration and power quality conditioning.

    PubMed

    Dai, NingYi; Lam, Chi-Seng; Zhang, WenChen

    2014-01-01

    In order to utilize the energy from the renewable energy sources, power conversion system is necessary, in which the voltage source inverter (VSI) is usually the last stage for injecting power to the grid. It is an economical solution to add the function of power quality conditioning to the grid-connected VSI in the low-voltage distribution system. Two multifunctional VSIs are studied in this paper, that is, inductive-coupling VSI and capacitive-coupling VSI, which are named after the fundamental frequency impedance of their coupling branch. The operation voltages of the two VSIs are compared when they are used for renewable energy integration and power quality conditioning simultaneously. The operation voltage of the capacitive-coupling VSI can be set much lower than that of the inductive-coupling VSI when reactive power is for compensating inductive loads. Since a large portion of the loads in the distribution system are inductive, the capacitive-coupling VSI is further studied. The design and control method of the multifunctional capacitive-coupling VSI are proposed in this paper. Simulation and experimental results are provided to show its validity.

  1. Optical remote sensing and correlation of office equipment functional state and stress levels via power quality disturbances inefficiencies

    NASA Astrophysics Data System (ADS)

    Sternberg, Oren; Bednarski, Valerie R.; Perez, Israel; Wheeland, Sara; Rockway, John D.

    2016-09-01

    Non-invasive optical techniques pertaining to the remote sensing of power quality disturbances (PQD) are part of an emerging technology field typically dominated by radio frequency (RF) and invasive-based techniques. Algorithms and methods to analyze and address PQD such as probabilistic neural networks and fully informed particle swarms have been explored in industry and academia. Such methods are tuned to work with RF equipment and electronics in existing power grids. As both commercial and defense assets are heavily power-dependent, understanding electrical transients and failure events using non-invasive detection techniques is crucial. In this paper we correlate power quality empirical models to the observed optical response. We also empirically demonstrate a first-order approach to map household, office and commercial equipment PQD to user functions and stress levels. We employ a physics-based image and signal processing approach, which demonstrates measured non-invasive (remote sensing) techniques to detect and map the base frequency associated with the power source to the various PQD on a calibrated source.

  2. Multifunctional Voltage Source Inverter for Renewable Energy Integration and Power Quality Conditioning

    PubMed Central

    Dai, NingYi; Lam, Chi-Seng; Zhang, WenChen

    2014-01-01

    In order to utilize the energy from the renewable energy sources, power conversion system is necessary, in which the voltage source inverter (VSI) is usually the last stage for injecting power to the grid. It is an economical solution to add the function of power quality conditioning to the grid-connected VSI in the low-voltage distribution system. Two multifunctional VSIs are studied in this paper, that is, inductive-coupling VSI and capacitive-coupling VSI, which are named after the fundamental frequency impedance of their coupling branch. The operation voltages of the two VSIs are compared when they are used for renewable energy integration and power quality conditioning simultaneously. The operation voltage of the capacitive-coupling VSI can be set much lower than that of the inductive-coupling VSI when reactive power is for compensating inductive loads. Since a large portion of the loads in the distribution system are inductive, the capacitive-coupling VSI is further studied. The design and control method of the multifunctional capacitive-coupling VSI are proposed in this paper. Simulation and experimental results are provided to show its validity. PMID:25177725

  3. Comparison between family power structure and the quality of parent-child interaction among the delinquent and non-delinquent adolescents.

    PubMed

    Khodabakhshi Koolaee, Anahita; Shaghelani Lor, Hossein; Soleimani, Ali Akbar; Rahmatizadeh, Masoumeh

    2014-06-01

    Few studies indicate that most behavioral problems are due to family dysfunction and inappropriate family environment. It seems that the family of the delinquent adolescent is unbalanced in the power structure and parenting style. The present study compares the family power structure and parent-child relationship quality in delinquent and non-delinquent young subjects in Tehran. Eighty students of secondary schools aged between 15 and 18 in Tehran were enrolled with cluster sampling method and 80 delinquent adolescents of the Correction and Rehabilitation Centers aged between 15 and 18 were chosen with a convenience sampling method. They responded to an instrument of family power structure (Child-parents relationship inventory). Data was compared between these two groups by utilizing the independent and dependent t-test and Levene's test. The findings indicated there is a significant difference between delinquent and non-delinquent adolescents in family power structure and its subscales (P < 0.001) and father-child relationship quality (P < 0.005). Also, there is no statistically significant difference between these two groups in mother-child relationship quality (P < 0.005). Besides, the results revealed that delinquent adolescents were significantly different regarding the quality of parent-child relationship (P < 0.001). These results emphasize that an inappropriate decision making process pattern in a family has a significant effect on deviant behavior in adolescents. The fathers' parenting is more strongly linked to their sons' delinquency. So, family power structure and parent-child relationship can be considered in therapeutic interventions (prevention and treatment) for adolescents' delinquency.

  4. Simulations of far-field optical beam quality influenced by the thermal distortion of the secondary mirror for high-power laser system

    NASA Astrophysics Data System (ADS)

    Guo, Ruhai; Chen, Ning; Zhuang, Xinyu; Wang, Bing

    2015-02-01

    In order to research the influence on the beam quality due to thermal deformation of the secondary mirror in the high power laser system, the theoretical simulation study is performed. Firstly, three typical laser power 10kW, 50kW and 100kW with the wavelength 1.064μm are selected to analyze thermal deformation of mirror through the finite element analyze of thermodynamics instantaneous method. Then the wavefront aberration can be calculated by ray-tracing theory. Finally, focus spot radius,beam quality (BQ) of far-filed beam can be calculated and comparably analyzed by Fresnel diffraction integration. The simulation results show that with the increasing laser power, the optical aberration of beam director gets worse, the far-field optical beam quality decrease, which makes the laser focus spot broadening and the peak optical intensity of center decreasing dramatically. Comparing the clamping ring and the three-point clamping, the former is better than the latter because the former only induces the rotation symmetric deformation and the latter introduces additional astigmatism. The far-field optical beam quality can be improved partly by simply adjusting the distance between the main mirror and the secondary mirror. But the far-field power density is still the one tenth as that without the heat distortion of secondary mirror. These results can also provide the reference to the thermal aberration analyze for high power laser system and can be applied to the field of laser communication system and laser weapon etc.

  5. Renewable Energy Development on Fort Mojave Reservation Feasiblity Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Russell Gum, ERCC analytics LLC

    2008-03-17

    The Ft. Mojave tribe, whose reservation is located along the Colorado River in the states of Arizona, California, and Nevada near the point where all three states meet, has a need for increased energy supplies. This need is a direct result of the aggressive and successful economic development projects undertaken by the tribe in the last decade. While it is possible to contract for additional energy supplies from fossil fuel sources it was the desire of the tribal power company, AHA MACAV Power Service (AMPS) to investigate the feasibility and desirability of producing power from renewable sources as an alternativemore » to increased purchase of fossil fuel generated power and as a possible enterprise to export green power. Renewable energy generated on the reservation would serve to reduce the energy dependence of the tribal enterprises on off reservation sources of energy and if produced in excess of reservation needs, add a new enterprise to the current mix of economic activities on the reservation. Renewable energy development would also demonstrate the tribe’s support for improving environmental quality, sustainability, and energy independence both on the reservation and for the larger community.« less

  6. 75 FR 28592 - Notice of Public Scoping Meetings for the Missouri River Authorized Purposes Study, Missouri...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ..., navigation, irrigation, power, water supply, water quality, recreation, and fish and wildlife. ADDRESSES..., navigation, irrigation, power, water supply, water quality, recreation, and fish and wildlife. Section 108 of... judicial rulings to determine if changes to the authorized project purposes and existing federal water...

  7. Best Practices: Power Quality and Integrated Testing at JSC

    NASA Technical Reports Server (NTRS)

    Davis, Lydia

    2018-01-01

    This presentation discusses Best Practices for Power Quality and Integrated Testing at JSC in regards to electrical systems. These high-level charts include mostly generic information; however, a specific issue is discussed involving flight hardware that could have been discovered prior to flight with an integrated test.

  8. Power and Resistance: Leading Change in Medical Education

    ERIC Educational Resources Information Center

    Sundberg, Kristina; Josephson, Anna; Reeves, Scott; Nordquist, Jonas

    2017-01-01

    A key role for educational leaders within undergraduate medical education is to continually improve the quality of education; global quality health care is the goal. This paper reports the findings from a study employing a power model to highlight how educational leaders influence the development of undergraduate medical curricula and the…

  9. Far field and wavefront characterization of a high-power semiconductor laser for free space optical communications

    NASA Technical Reports Server (NTRS)

    Cornwell, Donald M., Jr.; Saif, Babak N.

    1991-01-01

    The spatial pointing angle and far field beamwidth of a high-power semiconductor laser are characterized as a function of CW power and also as a function of temperature. The time-averaged spatial pointing angle and spatial lobe width were measured under intensity-modulated conditions. The measured pointing deviations are determined to be well within the pointing requirements of the NASA Laser Communications Transceiver (LCT) program. A computer-controlled Mach-Zehnder phase-shifter interferometer is used to characterize the wavefront quality of the laser. The rms phase error over the entire pupil was measured as a function of CW output power. Time-averaged measurements of the wavefront quality are also made under intensity-modulated conditions. The measured rms phase errors are determined to be well within the wavefront quality requirements of the LCT program.

  10. High performance terahertz metasurface quantum-cascade VECSEL with an intra-cryostat cavity

    DOE PAGES

    Xu, Luyao; Curwen, Christopher A.; Reno, John L.; ...

    2017-09-04

    A terahertz quantum-cascade (QC) vertical-external-cavity surface-emitting-laser (VECSEL) is demonstrated with over 5 mW power in continuous-wave and single-mode operation above 77 K, in combination with a near-Gaussian beam pattern with full-width half-max divergence as narrow as ~5° × 5°, with no evidence of thermal lensing. This is realized by creating an intra-cryostat VECSEL cavity to reduce the cavity loss and designing an active focusing metasurface reflector with low power dissipation for efficient heat removal. Compared with a conventional quantumcascade laser based on a metal-metal waveguide, the intra-cryostat QC-VECSEL exhibits significant improvements in both output power level and beam pattern. Also,more » the intra-cryostat configuration newly allows evaluation of QC-VECSEL operation vs. temperature, showing a maximum pulsed mode operating temperature of 129 K. While the threshold current density in the QC-VECSEL is worse in comparison to a conventional edge-emitting metal-metal waveguide QClaser, the beam quality, slope efficiency, maximum power, and thermal resistance are all significantly improved.« less

  11. High-quality weather data for grid integration studies

    NASA Astrophysics Data System (ADS)

    Draxl, C.

    2016-12-01

    As variable renewable power penetration levels increase in power systems worldwide, renewable integration studies are crucial to ensure continued economic and reliable operation of the power grid. In this talk we will shed light on requirements for grid integration studies as far as wind and solar energy are concerned. Because wind and solar plants are strongly impacted by weather, high-resolution and high-quality weather data are required to drive power system simulations. Future data sets will have to push limits of numerical weather prediction to yield these high-resolution data sets, and wind data will have to be time-synchronized with solar data. Current wind and solar integration data sets will be presented. The Wind Integration National Dataset (WIND) Toolkit is the largest and most complete grid integration data set publicly available to date. A meteorological data set, wind power production time series, and simulated forecasts created using the Weather Research and Forecasting Model run on a 2-km grid over the continental United States at a 5-min resolution is now publicly available for more than 126,000 land-based and offshore wind power production sites. The Solar Integration National Dataset (SIND) is available as time synchronized with the WIND Toolkit, and will allow for combined wind-solar grid integration studies. The National Solar Radiation Database (NSRDB) is a similar high temporal- and spatial resolution database of 18 years of solar resource data for North America and India. Grid integration studies are also carried out in various countries, which aim at increasing their wind and solar penetration through combined wind and solar integration data sets. We will present a multi-year effort to directly support India's 24x7 energy access goal through a suite of activities aimed at enabling large-scale deployment of clean energy and energy efficiency. Another current effort is the North-American-Renewable-Integration-Study, with the aim of providing a seamless data set across borders for a whole continent, to simulate and analyze the impacts of potential future large wind and solar power penetrations on bulk power system operations.

  12. Density separation as a strategy to reduce the enzyme load of preharvest sprouted wheat and enhance its bread making quality.

    PubMed

    Olaerts, Heleen; De Bondt, Yamina; Courtin, Christophe M

    2018-02-15

    As preharvest sprouting of wheat impairs its use in food applications, postharvest solutions for this problem are required. Due to the high kernel to kernel variability in enzyme activity in a batch of sprouted wheat, the potential of eliminating severely sprouted kernels based on density differences in NaCl solutions was evaluated. Compared to higher density kernels, lower density kernels displayed higher α-amylase, endoxylanase, and peptidase activities as well as signs of (incipient) protein, β-glucan and arabinoxylan breakdown. By discarding lower density kernels of mildly and severely sprouted wheat batches (11% and 16%, respectively), density separation increased flour FN of the batch from 280 to 345s and from 135 to 170s and increased RVA viscosity. This in turn improved dough handling, bread crumb texture and crust color. These data indicate that density separation is a powerful technique to increase the quality of a batch of sprouted wheat. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Integrating Safety and Mission Assurance into Systems Engineering Modeling Practices

    NASA Technical Reports Server (NTRS)

    Beckman, Sean; Darpel, Scott

    2015-01-01

    During the early development of products, flight, or experimental hardware, emphasis is often given to the identification of technical requirements, utilizing such tools as use case and activity diagrams. Designers and project teams focus on understanding physical and performance demands and challenges. It is typically only later, during the evaluation of preliminary designs that a first pass, if performed, is made to determine the process, safety, and mission quality assurance requirements. Evaluation early in the life cycle, though, can yield requirements that force a fundamental change in design. This paper discusses an alternate paradigm for using the concepts of use case or activity diagrams to identify safety hazard and mission quality assurance risks and concerns using the same systems engineering modeling tools being used to identify technical requirements. It contains two examples of how this process might be used in the development of a space flight experiment, and the design of a Human Powered Pizza Delivery Vehicle, along with the potential benefits to decrease development time, and provide stronger budget estimates.

  14. Effect of carob (Ceratonia siliqua L.) flour on the antioxidant potential, nutritional quality, and sensory characteristics of fortified durum wheat pasta.

    PubMed

    Sęczyk, Łukasz; Świeca, Michał; Gawlik-Dziki, Urszula

    2016-03-01

    This paper presents a study on the effect of carob flour addition from 1% to 5% (w/w) on phenolics content, antioxidant activity, nutritional quality, and sensory attributes of wheat pasta. An increase of about 2-folds, 18-folds and 3-folds in phenolics content, antiradical activity and reducing power for pasta fortified with 5% of carob flour was observed, respectively, compared to the control. Expected glycemic index (eGI) was increased proportionally to the substitution level and ranged between 72.2 and 83.9 for 1-5% of supplement, respectively. Furthermore, pasta fortification affected the in vitro bioaccessibility of nutrients. In case of 5% supplemented pasta, the digestibility of starch and protein decreased by about 9% compared to the control. The replacement of semolina with carob flour from 1% to 5% had no significant effect on pasta sensory attributes. In conclusion, carob flour seems to be a promising functional ingredient for pasta fortification. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Ultra-short pulse delivery at high average power with low-loss hollow core fibers coupled to TRUMPF's TruMicro laser platforms for industrial applications

    NASA Astrophysics Data System (ADS)

    Baumbach, S.; Pricking, S.; Overbuschmann, J.; Nutsch, S.; Kleinbauer, J.; Gebs, R.; Tan, C.; Scelle, R.; Kahmann, M.; Budnicki, A.; Sutter, D. H.; Killi, A.

    2017-02-01

    Multi-megawatt ultrafast laser systems at micrometer wavelength are commonly used for material processing applications, including ablation, cutting and drilling of various materials or cleaving of display glass with excellent quality. There is a need for flexible and efficient beam guidance, avoiding free space propagation of light between the laser head and the processing unit. Solid core step index fibers are only feasible for delivering laser pulses with peak powers in the kW-regime due to the optical damage threshold in bulk silica. In contrast, hollow core fibers are capable of guiding ultra-short laser pulses with orders of magnitude higher peak powers. This is possible since a micro-structured cladding confines the light within the hollow core and therefore minimizes the spatial overlap between silica and the electro-magnetic field. We report on recent results of single-mode ultra-short pulse delivery over several meters in a lowloss hollow core fiber packaged with industrial connectors. TRUMPF's ultrafast TruMicro laser platforms equipped with advanced temperature control and precisely engineered opto-mechanical components provide excellent position and pointing stability. They are thus perfectly suited for passive coupling of ultra-short laser pulses into hollow core fibers. Neither active beam launching components nor beam trackers are necessary for a reliable beam delivery in a space and cost saving packaging. Long term tests with weeks of stable operation, excellent beam quality and an overall transmission efficiency of above 85 percent even at high average power confirm the reliability for industrial applications.

  16. Physical quality characteristics of the microwave-dried breadfruit powders due to different processing conditions

    NASA Astrophysics Data System (ADS)

    Taruna, I.; Hakim, A. L.; Sutarsi

    2018-03-01

    Production of breadfruit powder has been an option to make easy its uses in various food processing. Accordingly, there is a need recently to apply advanced drying method, i.e. microwave drying, for improving quality since conventional methods produced highly variable product quality and required longer process. The present work was aimed to study the effect of microwave power and grinding time on physical quality of breadfruit powders. The experiment was done initially by drying breadfruit slices in a microwave dryer at power level of 420, 540, and 720 W and then grinding for 3, 5, and 7 min to get powdery product of less than 80 mesh. The physical quality of breadfruit powders were measured in terms of fineness modulus (FM), average particle size (D), whiteness (WI), total color difference (ΔE), water absorption (Wa), oil absorption (La), bulk density (ρb) and consistency gel (Gc). The results showed that physical quality of powders and its ranged-values included the FM (2.08-2.62), D (0.44-0.68 mm), WI (75.2-77.9), ΔE (7.4-10.5), Wa (5.5-6.2 ml/g), La (0.7-0.9 ml/g), ρb (0.62-0.70 g/cm3) and Gc (41.3-46.8 mm). The experiment revealed that variation of microwave power and grinding time affected significantly the quality of the breadfruit powders. However, microwave power was more dominant factor to affect quality of breadfruit powder in comparison to the grinding time.

  17. Prestimulus alpha power predicts fidelity of sensory encoding in perceptual decision making.

    PubMed

    Lou, Bin; Li, Yun; Philiastides, Marios G; Sajda, Paul

    2014-02-15

    Pre-stimulus α power has been shown to correlate with the behavioral accuracy of perceptual decisions. In most cases, these correlations have been observed by comparing α power for different behavioral outcomes (e.g. correct vs incorrect trials). In this paper we investigate such covariation within the context of behaviorally-latent fluctuations in task-relevant post-stimulus neural activity. Specially we consider variations of pre-stimulus α power with post-stimulus EEG components in a two alternative forced choice visual discrimination task. EEG components, discriminative of stimulus class, are identified using a linear multivariate classifier and only the variability of the components for correct trials (regardless of stimulus class, and for nominally identical stimuli) are correlated with the corresponding pre-stimulus α power. We find a significant relationship between the mean and variance of the pre-stimulus α power and the variation of the trial-to-trial magnitude of an early post-stimulus EEG component. This relationship is not seen for a later EEG component that is also discriminative of stimulus class and which has been previously linked to the quality of evidence driving the decision process. Our results suggest that early perceptual representations, rather than temporally later neural correlates of the perceptual decision, are modulated by pre-stimulus state. © 2013 Elsevier Inc. All rights reserved.

  18. Prestimulus alpha power predicts fidelity of sensory encoding in perceptual decision making

    PubMed Central

    Lou, Bin; Li, Yun; Philiastides, Marios G.; Sajda, Paul

    2013-01-01

    Pre-stimulus α power has been shown to correlate with the behavioral accuracy of perceptual decisions. In most cases, these correlations have been observed by comparing α power for different behavioral outcomes (e.g. correct vs incorrect trials). In this paper we investigate such covariation within the context of behaviorally-latent fluctuations in task-relevant post-stimulus neural activity. Specially we consider variations of pre-stimulus α power with post-stimulus EEG components in a two alternative forced choice visual discrimination task. EEG components, discriminative of stimulus class, are identified using a linear multivariate classifier and only the variability of the components for correct trials (regardless of stimulus class, and for nominally identical stimuli) are correlated with the corresponding pre-stimulus α power. We find a significant relationship between the mean and variance of the pre-stimulus α power and the variation of the trial-to-trial magnitude of an early post-stimulus EEG component. This relationship is not seen for a later EEG component that is also discriminative of stimulus class and which has been previously linked to the quality of evidence driving the decision process. Our results suggest that early perceptual representations, rather than temporally later neural correlates of the perceptual decision, are modulated by pre-stimulus state. PMID:24185020

  19. Third order intermodulation distortion in HTS Josephson Junction downconverter at 12GHz

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suzuki, Katsumi; Hayashi, Kunihiko; Fujimoto, Manabu

    1994-12-31

    Here the authors first report on the microwave characteristics of the third order intermodulation distortion(IMD3) in High-Tc Superconductor (HTS) Josephson Junction (JJ) Downconverter at 12GHz. They have successfully developed high quality nonlinear YBCO microbridge Josephson junctions for such an active MMIC as a mixer with RF, LO, IF and bias filters, which have been fabricated on (100) MgO substrates with 20mm x 20mm x 0.5mm dimensions. The minimum conversion loss of the JJ mixer is 11 dB at very small local microwave input power LO= {minus}20dBm which is two order less than Schottky diode mixer. Consequently, this small optimum LOmore » power gives the small RF input power at which the output IF power of the YBCO mixer saturates. Two-tone third-order intercept point(IP3) performance is a significantly important figure of merit typically used to define linearity of devices and circuits. The RF input power = {minus}15dBm at the IP3 point is obtained for the YBCO mixer at 15K and LO = 10.935GHz with {minus}22dBm. The have successfully measured the dependence of IMD3 on temperature, bias current and LO power.« less

  20. Ultrasonication and the quality of human milk: variation of power and time of exposure.

    PubMed

    Christen, Lukas; Lai, Ching Tat; Hartmann, Peter E

    2012-08-01

    Donor human milk is pasteurized to prevent the potential risk of the transmission of pathogens to preterm infants. Currently, Holder pasteurization (human milk held at 62·5°C for 30 min) is used in most human milk banks, but has the disadvantage that it results in excessive inactivation of important bioactive components. Power-ultrasound (20-100 kHz) is an emerging technology for the preservation of foods and could be an alternative method for the treatment of human milk. The aim of this study was to investigate the effect of different ultrasound settings on the elimination of Escherichia coli and the retention of bile salt stimulated lipase (BSSL) activity. Ultrasonication with a constant power decreased Esch. coli viability exponentially over time until the processing temperature increased to sub-pasteurization level to between 51·4 and 58·5°C, then a log10 1·3 decrease was observed (P<0·05). BSSL activity decreased to 91% until a temperature of 51·4°C and then it decreased to 8% between 51·4 and 64·9°C. Ultrasonication with a constant energy and various power and exposure times showed the highest temperature (53·7°C) when treated with the longest exposure time and lowest ultrasound-power (276 s at 3·62 W) compared with 37·6°C for 39 s at 25·64 W. The findings predict that the viability of Esch. coli could be reduced by log10 5 with a minimal loss of activity of BSSL by applying 13·8 kJ of energy in 12 ml of human milk using high ultrasound power over a short exposure time to ensure that the temperature remains below the critical level for protein denaturation. Alternatively, the use of lower power settings such as the 26 W used in the present studies would require a cooling system to ensure the human milk BSSL was protected against temperature denaturation.

  1. Demonstration of Essential Reliability Services by a 300-MW Solar Photovoltaic Power Plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Loutan, Clyde; Klauer, Peter; Chowdhury, Sirajul

    The California Independent System Operator (CAISO), First Solar, and the National Renewable Energy Laboratory (NREL) conducted a demonstration project on a large utility-scale photovoltaic (PV) power plant in California to test its ability to provide essential ancillary services to the electric grid. With increasing shares of solar- and wind-generated energy on the electric grid, traditional generation resources equipped with automatic governor control (AGC) and automatic voltage regulation controls -- specifically, fossil thermal -- are being displaced. The deployment of utility-scale, grid-friendly PV power plants that incorporate advanced capabilities to support grid stability and reliability is essential for the large-scale integrationmore » of PV generation into the electric power grid, among other technical requirements. A typical PV power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. In this way, PV power plants can be used to mitigate the impact of variability on the grid, a role typically reserved for conventional generators. In August 2016, testing was completed on First Solar's 300-MW PV power plant, and a large amount of test data was produced and analyzed that demonstrates the ability of PV power plants to use grid-friendly controls to provide essential reliability services. These data showed how the development of advanced power controls can enable PV to become a provider of a wide range of grid services, including spinning reserves, load following, voltage support, ramping, frequency response, variability smoothing, and frequency regulation to power quality. Specifically, the tests conducted included various forms of active power control such as AGC and frequency regulation; droop response; and reactive power, voltage, and power factor controls. This project demonstrated that advanced power electronics and solar generation can be controlled to contribute to system-wide reliability. It was shown that the First Solar plant can provide essential reliability services related to different forms of active and reactive power controls, including plant participation in AGC, primary frequency control, ramp rate control, and voltage regulation. For AGC participation in particular, by comparing the PV plant testing results to the typical performance of individual conventional technologies, we showed that regulation accuracy by the PV plant is 24-30 points better than fast gas turbine technologies. The plant's ability to provide volt-ampere reactive control during periods of extremely low power generation was demonstrated as well. The project team developed a pioneering demonstration concept and test plan to show how various types of active and reactive power controls can leverage PV generation's value from being a simple variable energy resource to a resource that provides a wide range of ancillary services. With this project's approach to a holistic demonstration on an actual, large, utility-scale, operational PV power plant and dissemination of the obtained results, the team sought to close some gaps in perspectives that exist among various stakeholders in California and nationwide by providing real test data.« less

  2. Relating landscape characteristics to non-point source pollution in mine waste-located watersheds using geospatial techniques.

    PubMed

    Xiao, Huaguo; Ji, Wei

    2007-01-01

    Landscape characteristics of a watershed are important variables that influence surface water quality. Understanding the relationship between these variables and surface water quality is critical in predicting pollution potential and developing watershed management practices to eliminate or reduce pollution risk. To understand the impacts of landscape characteristics on water quality in mine waste-located watersheds, we conducted a case study in the Tri-State Mining District which is located in the conjunction of three states (Missouri, Kansas and Oklahoma). Severe heavy metal pollution exists in that area resulting from historical mining activities. We characterized land use/land cover over the last three decades by classifying historical multi-temporal Landsat imagery. Landscape metrics such as proportion, edge density and contagion were calculated based on the classified imagery. In-stream water quality data over three decades were collected, including lead, zinc, iron, cadmium, aluminum and conductivity which were used as key water quality indicators. Statistical analyses were performed to quantify the relationship between landscape metrics and surface water quality. Results showed that landscape characteristics in mine waste-located watersheds could account for as much as 77% of the variation of water quality indicators. A single landscape metric alone, such as proportion of mine waste area, could be used to predict surface water quality; but its predicting power is limited, usually accounting for less than 60% of the variance of water quality indicators.

  3. Quality evaluation of Hypericum ascyron extract by two-dimensional high-performance liquid chromatography coupled with the colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.

    PubMed

    Li, Xiu-Mei; Luo, Xue-Gang; Zhang, Chao-Zheng; Wang, Nan; Zhang, Tong-Cun

    2015-02-01

    In this paper, a heart-cutting two-dimensional high-performance liquid chromatography coupled with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method was established for controlling the quality of different batches of Hypericum ascyron extract for the first time. In comparison with the common one-dimensional fingerprint, the second-dimensional fingerprint compiled additional spectral data and was hence more informative. The quality of H. ascyron extract was further evaluated by similarity measures and the same results were achieved, the correlation coefficients of the similarity of ten batches of H. ascyron extract were >0.99. Furthermore, we also evaluated the quality of the ten batches of H. ascyron extract by antibacterial activity. The result demonstrated that the quality of the ten batches of H. ascyron extract was not significantly different by MTT. Finally, we demonstrated that the second-dimensional fingerprint coupled with the MTT method was a more powerful tool to characterize the quality of samples of batch to batch. Therefore the proposed method could be used to comprehensively conduct the quality control of traditional Chinese medicines. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Comparative Analysis of the Specifications on the Power Quality of the European Union and the Russian Federation

    NASA Astrophysics Data System (ADS)

    Ded, A. V.; Maltsev, V. N.; Sikorski, S. P.

    2018-04-01

    Since July 2014 the interstate standard GOST 32144-2013 is the only document that defines standard requirements for the power quality in the territory of the Russian Federation. The new standard preamble specifies that this document considers the requirements of the European regional standard EN 50160-2010. However, GOST authors established the degree of standards conformity as nonequivalent. In connection with Russia's accession to the World Trade Organization (WTO) all requirements for goods including electric energy should correspond the international standard requirements. The article analyzes the above standard requirements and assesses the requirements for the power quality standards used in the European Union and in the Russian Federation.

  5. Health related quality of life in parents of six to eight year old children with Down syndrome.

    PubMed

    Marchal, Jan Pieter; Maurice-Stam, Heleen; Hatzmann, Janneke; van Trotsenburg, A S Paul; Grootenhuis, Martha A

    2013-11-01

    Raising a child with Down syndrome (DS) has been found to be associated with lowered health related quality of life (HRQoL) in the domains cognitive functioning, social functioning, daily activities and vitality. We aimed to explore which socio-demographics, child functioning and psychosocial variables were related to these HRQoL domains in parents of children with DS. Parents of 98 children with DS completed the TNO-AZL adult quality of life questionnaire (TAAQOL) and a questionnaire assessing socio-demographic, child functioning and psychosocial predictors. Using multiple linear regression analyses for each category of predictors, we selected relevant predictors for the final models. The final multiple linear regression models revealed that cognitive functioning was best predicted by the sleep of the child (β=.29, p<.01) and by the parent having given up a hobby (β=-.29, p<.01), social functioning by the quality of the partner relation (β=.34, p<.001), daily activities by the parent having to care for an ill friend or family member (β=-.31, p<.01), and vitality by the parent having enough personal time (β=.32, p<.01). Overall, psychosocial variables rather than socio-demographics or child functioning showed most consistent and powerful relations to the HRQoL domains of cognitive functioning, social functioning, daily activities and vitality. These psychosocial variables mainly related to social support and time pressure. Systematic screening of parents to detect problems timely, and interventions targeting the supportive network and the demands in time are recommended. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Reasons for using power tilt: perspectives from clients and therapists.

    PubMed

    Titus, Laura C; Miller Polgar, Janice

    2018-02-01

    A power tilt wheelchair allows independence in changing body position to address a variety of needs throughout the day; however, literature and clinical practice suggest that actual use varies greatly. This grounded theory study examined how power tilt was used in daily life from the perspectives of adults who used power tilt and therapists who prescribed this technology. A constant comparative approach was used to collect and analyze interview data from five people who use power tilt and six therapists who prescribe this technology. This paper presents the findings specific to understanding the reasons why power tilt was used, focusing on the relationships between tilt use and (1) the reasons for use, (2) the reasons for prescribing power tilt and (3) the associated amplitudes of tilt. This study advances knowledge related to how power tilt is used in daily life by elucidating that how the reasons for use are conceptualized is complex. The three relationships related to the reason for power tilt use identified in this paper have the potential to influence the quality of communication about power tilt use in clinical practice between therapist and client and in research between researcher and participant. Implications for Rehabilitation: Understanding the inconsistencies and variations in how power tilt is used in daily life is dependent on exploring the reasons beyond the words or terms expressed to describe use. Reasons for tilt use are context dependent, particularly the activity occurring at the time of tilt use, the associated amplitude of tilt and the influence of other reasons occurring at the same time.

  7. Quality factor concept in piezoceramic transformer performance description.

    PubMed

    Mezheritsky, Alex V

    2006-02-01

    A new general approach based on the quality factor concept to piezoceramic transformer (PT) performance description is proposed. The system's quality factor, material elastic anisotropy, and coupling factors of the input and output sections of an electrically excited and electrically loaded PT fully characterize its resonance and near-resonance behavior. The PT efficiency, transformation ratio, and input and output power were analytically analyzed and simulated as functions of the load and frequency for the simplest classical Langevin-type and Rosen-type PT designs. A new formulation of the electrical input impedance allows one to separate the power consumed by PT from the power transferred into the load. The system's PT quality factor takes into account losses in each PT "input-output-load" functional components. The loading process is changing PT input electrical impedance on the way that under loading the minimum series impedance is increasing and the maximum parallel impedance is decreasing coincidentally. The quality-factors ratio, between the states of fully loaded and nonloaded PT, is one of the best measures of PTs dynamic performance--practically, the lower the ratio is, the better PT efficiency. A simple and effective method for the loaded PT quality factor determination is proposed. As was found, a piezoceramic with low piezoelectric anisotropy is required to provide maximum PT efficiency and higher corresponding voltage gain. Limitations on the PT output voltage and power, caused by nonlinear effects in piezoceramics, were established.

  8. High-energy laser activities at MBDA Germany

    NASA Astrophysics Data System (ADS)

    Mohring, Bernd; Dietrich, Stephan; Tassini, Leonardo; Protz, Rudolf; Geidek, Franz; Zoz, Jürgen

    2013-05-01

    At MBDA Germany a concept for a high-energy laser weapon system is investigated, which is based on existing industrial laser sources. Due to the enormous progress in the field of high-power fiber lasers, commercial industrial fiber lasers are now available delivering a nearly-diffraction limited beam quality with power levels of up to 10 kW. By using a geometric beam coupling scheme, a number of individual high-power fiber laser beams are combined together using one common beam director telescope. A total laser beam power of more than 100 kW can be achieved, which is sufficient for an operational laser weapon system. The individual beams from the different lasers are steered by servo-loops using fast tip-tilt mirrors. This principle enables the concentration of the total laser beam power at one common focal point on a distant target, also allowing fine tracking of target movements and first-order compensation of turbulence effects on laser beam propagation. The proposed beam combination concept was demonstrated by using different experimental set-ups. A number of experiments were performed successfully to investigate laser beam target interaction and target fine tracking, also at large distances and at moving targets. Content and results of these investigations are reported, which demonstrate the complete engagement sequence for a C-RAM scenario. This includes subsequent steps of target acquisition by radar and IR optics, followed by large angle coarse tracking, active fine tracking and destruction of the target by the laser system. This successful implementation of geometric beam combining is an important step for the realization of a laser weapon system in the near future.

  9. Photoluminescence investigation of type-II GaSb/GaAs quantum dots grown by liquid phase epitaxy

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Hu, Shuhong; Xie, Hao; Lin, Hongyu; lu, Hongbo; Wang, Chao; Sun, Yan; Dai, Ning

    2018-06-01

    GaSb quantum dots (QDs) with an areal density of ∼1 × 1010 cm-2 are successfully grown by the modified (rapid slider) liquid phase epitaxy technique. The morphology of the QDs has been investigated by scanning electron microscope (SEM) and atom force microscope (AFM). The power-dependence and temperature-dependence photoluminescence (PL) spectra have been studied. The bright room-temperature PL suggests a good luminescence quality of GaSb QDs/GaAs matrix system. The type-II alignment of the GaSb QDs/GaAs matrix system is verified by the blue-shift of the QDs peak with the increase of excitation power. From the temperature-dependence PL spectra, the activation energy of QDs is determined to be 111 meV.

  10. 7.5 W blue light generation at 452 nm by internal frequency doubling of a continuous-wave Nd-doped fiber laser.

    PubMed

    Leconte, Baptiste; Gilles, Hervé; Robin, Thierry; Cadier, Benoit; Laroche, Mathieu

    2018-04-16

    We present the first frequency-doubled neodymium-doped fiber laser generating multi-watt CW power near 450 nm. A bow-tie resonator incorporating a LBO nonlinear crystal is integrated within a Nd-doped fiber laser emitting near 900 nm. This scheme achieves an IR to blue conversion efficiency close to 55% without any active control of the internal resonant cavity. As a result, up to 7.5 W of linearly-polarized blue power is generated, with beam quality factors M x 2 ~1.0 and M y 2 ~1.5. A simple numerical model has been developed to optimize and analyse the IR to blue conversion efficiency in the resonant cavity. Performance limitations and prospects for further improvements are discussed.

  11. Prestimulus influences on auditory perception from sensory representations and decision processes.

    PubMed

    Kayser, Stephanie J; McNair, Steven W; Kayser, Christoph

    2016-04-26

    The qualities of perception depend not only on the sensory inputs but also on the brain state before stimulus presentation. Although the collective evidence from neuroimaging studies for a relation between prestimulus state and perception is strong, the interpretation in the context of sensory computations or decision processes has remained difficult. In the auditory system, for example, previous studies have reported a wide range of effects in terms of the perceptually relevant frequency bands and state parameters (phase/power). To dissociate influences of state on earlier sensory representations and higher-level decision processes, we collected behavioral and EEG data in human participants performing two auditory discrimination tasks relying on distinct acoustic features. Using single-trial decoding, we quantified the relation between prestimulus activity, relevant sensory evidence, and choice in different task-relevant EEG components. Within auditory networks, we found that phase had no direct influence on choice, whereas power in task-specific frequency bands affected the encoding of sensory evidence. Within later-activated frontoparietal regions, theta and alpha phase had a direct influence on choice, without involving sensory evidence. These results delineate two consistent mechanisms by which prestimulus activity shapes perception. However, the timescales of the relevant neural activity depend on the specific brain regions engaged by the respective task.

  12. Prestimulus influences on auditory perception from sensory representations and decision processes

    PubMed Central

    McNair, Steven W.

    2016-01-01

    The qualities of perception depend not only on the sensory inputs but also on the brain state before stimulus presentation. Although the collective evidence from neuroimaging studies for a relation between prestimulus state and perception is strong, the interpretation in the context of sensory computations or decision processes has remained difficult. In the auditory system, for example, previous studies have reported a wide range of effects in terms of the perceptually relevant frequency bands and state parameters (phase/power). To dissociate influences of state on earlier sensory representations and higher-level decision processes, we collected behavioral and EEG data in human participants performing two auditory discrimination tasks relying on distinct acoustic features. Using single-trial decoding, we quantified the relation between prestimulus activity, relevant sensory evidence, and choice in different task-relevant EEG components. Within auditory networks, we found that phase had no direct influence on choice, whereas power in task-specific frequency bands affected the encoding of sensory evidence. Within later-activated frontoparietal regions, theta and alpha phase had a direct influence on choice, without involving sensory evidence. These results delineate two consistent mechanisms by which prestimulus activity shapes perception. However, the timescales of the relevant neural activity depend on the specific brain regions engaged by the respective task. PMID:27071110

  13. Solidarity-conflict and ambivalence: testing two conceptual frameworks and their impact on quality of life for older family members.

    PubMed

    Lowenstein, Ariela

    2007-03-01

    The purpose of this study was to test empirically two major conceptualizations of parent-child relations in later adulthood-intergenerational solidarity-conflict and ambivalence paradigms-and their predictive validity on elders' quality of life using comparative cross-national data. Data were from a sample of 2,064 elders (aged 75 and older) from the five-country OASIS study (Old Age and Autonomy: The Role of Service Systems and Intergenerational Family Solidarity; Norway, England, Germany, Spain, and Israel). Multivariate and block-recursive regression models estimated the predictivity of the two conceptualizations of family dynamics on quality of life controlling for country, personal characteristics, and activity of daily living functioning. Descriptive analyses indicated that family solidarity, especially the affective/cognitive component (called Solidarity A), was high in all five countries, whereas conflict and ambivalence were low. When I entered all three constructs into the regression Solidarity A, reciprocal intergenerational support and ambivalence predicted quality of life. Controlling for activity of daily living functioning, socioeconomics status, and country, intergenerational relations had only a weak explanatory power, and personal resources explained most of the variance. The data suggest that the three constructs exist simultaneously but in varying combinations, confirming that in cross-cultural contexts family cohesion predominates, albeit with low degrees of conflict and ambivalence. The solidarity construct evidenced relatively robust measurement. More work is required to enhance the ambivalence measurement.

  14. Quality Certification, Regulation and Power in Fair Trade

    ERIC Educational Resources Information Center

    Renard, Marie-Christine

    2005-01-01

    This article examines governance changes and shifting power relations within the fair-labelling network. These shifts are framed analytically by reference to broader changes in the agrofoods sector tied to the increasingly key role played by quality relations and standards in the production and marketing of food. The author argues that evident…

  15. Age associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    USDA-ARS?s Scientific Manuscript database

    SUMMARY: This 3 year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of ...

  16. 75 FR 34670 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; Revision to Emission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ... Promulgation of Air Quality Implementation Plans; Maryland; Revision to Emission Limitations for R. Paul Smith... revision pertains to revised emission limitations for the R. Paul Smith Power Station located in Washington... R. Paul Smith Power Station in Washington County. This facility had annual nitrogen oxides (NOx...

  17. CALiPER Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    none,

    2014-12-31

    This CALiPER report examines the characteristics of a subset of lamps from CALiPER Retail Lamps Study 3 in more detail. Specifically, it focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers.

  18. 18 CFR 410.1 - Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations. 410.1 Section 410.1 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS; WATER...

  19. Water-Chemistry and Its Utility Systems in CCP Power Units (Review)

    NASA Astrophysics Data System (ADS)

    Larin, B. M.

    2018-01-01

    Damageability of heat transfer surfaces of waste heat recovery steam generators (HRSG) of combined- cycle plants (CCP) can be reduced due to an increase in the quality of make-up and feed water, the use of phosphate-alkaline or amino compound water chemistry (WC), and improved chemical quality control of the heat carrier and make-up water preparation techniques. Temporary quality standards for the heat medium developed by the All-Russia Thermal Engineering institute (VTI) for CCP power units are presented in comparison with the IAPWS standards; preferences for the choice of a WC type for some power units commissioned in Russia in the first decade of this century are shown; and operational data on the quality of feed, boiler water, and steam for two large CCP-450 and CCP-425 power units are given. The state and prospects for the development of chemical-technological monitoring systems and CCP water treatment plants are noted. Estimability of some CCP diagnostic parameters by measuring specific electric conductivity and pH is shown. An extensive bibliography on this topic is given.

  20. Energy-Efficient Next-Generation Passive Optical Networks Based on Sleep Mode and Heuristic Optimization

    NASA Astrophysics Data System (ADS)

    Zulai, Luis G. T.; Durand, Fábio R.; Abrão, Taufik

    2015-05-01

    In this article, an energy-efficiency mechanism for next-generation passive optical networks is investigated through heuristic particle swarm optimization. Ten-gigabit Ethernet-wavelength division multiplexing optical code division multiplexing-passive optical network next-generation passive optical networks are based on the use of a legacy 10-gigabit Ethernet-passive optical network with the advantage of using only an en/decoder pair of optical code division multiplexing technology, thus eliminating the en/decoder at each optical network unit. The proposed joint mechanism is based on the sleep-mode power-saving scheme for a 10-gigabit Ethernet-passive optical network, combined with a power control procedure aiming to adjust the transmitted power of the active optical network units while maximizing the overall energy-efficiency network. The particle swarm optimization based power control algorithm establishes the optimal transmitted power in each optical network unit according to the network pre-defined quality of service requirements. The objective is controlling the power consumption of the optical network unit according to the traffic demand by adjusting its transmitter power in an attempt to maximize the number of transmitted bits with minimum energy consumption, achieving maximal system energy efficiency. Numerical results have revealed that it is possible to save 75% of energy consumption with the proposed particle swarm optimization based sleep-mode energy-efficiency mechanism compared to 55% energy savings when just a sleeping-mode-based mechanism is deployed.

  1. Colloidal-Quantum-Dot Ring Lasers with Active Color Control.

    PubMed

    le Feber, Boris; Prins, Ferry; De Leo, Eva; Rabouw, Freddy T; Norris, David J

    2018-02-14

    To improve the photophysical performance of colloidal quantum dots for laser applications, sophisticated core/shell geometries have been developed. Typically, a wider bandgap semiconductor is added as a shell to enhance the gain from the quantum-dot core. This shell is designed to electronically isolate the core, funnel excitons to it, and reduce nonradiative Auger recombination. However, the shell could also potentially provide a secondary source of gain, leading to further versatility in these materials. Here we develop high-quality quantum-dot ring lasers that not only exhibit lasing from both the core and the shell but also the ability to switch between them. We fabricate ring resonators (with quality factors up to ∼2500) consisting only of CdSe/CdS/ZnS core/shell/shell quantum dots using a simple template-stripping process. We then examine lasing as a function of the optical excitation power and ring radius. In resonators with quality factors >1000, excitons in the CdSe cores lead to red lasing with thresholds at ∼25 μJ/cm 2 . With increasing power, green lasing from the CdS shell emerges (>100 μJ/cm 2 ) and then the red lasing begins to disappear (>250 μJ/cm 2 ). We present a rate-equation model that can explain this color switching as a competition between exciton localization into the core and stimulated emission from excitons in the shell. Moreover, by lowering the quality factor of the cavity we can engineer the device to exhibit only green lasing. The mechanism demonstrated here provides a potential route toward color-switchable quantum-dot lasers.

  2. Optimisation of microwave-assisted processing in production of pineapple jam

    NASA Astrophysics Data System (ADS)

    Ismail, Nur Aisyah Mohd; Abdullah, Norazlin; Muhammad, Norhayati

    2017-10-01

    Pineapples are available all year round since they are unseasonal fruits. Due to the continuous harvesting of the fruit, the retailers and farmers had to find a solution such as the processing of pineapple into jam, to treat the unsuccessfully sold pineapples. The direct heating of pineapple puree during the production of pineapple jam can cause over degradation of quality of the fresh pineapple. Thus, this study aims to optimise the microwave-assisted processing conditions for producing pineapple jam which could reduce water activity and meets minimum requirement for pH and total soluble solids contents of fruit jam. The power and time of the microwave processing were chosen as the factors, while the water activity, pH and total soluble solids (TSS) content of the pineapple jam were determined as responses to be optimised. The microwave treatment on the pineapple jam was able to give significant effect on the water activity and TSS content of the pineapple jam. The optimum power and time for the microwave processing of pineapple jam is 800 Watt and 8 minutes, respectively. The use of domestic microwave oven for the pineapple jam production results in acceptable pineapple jam same as conventional fruit jam sold in the marketplace.

  3. Power Spectrum of a Noisy System Close to a Heteroclinic Orbit

    NASA Astrophysics Data System (ADS)

    Giner-Baldó, Jordi; Thomas, Peter J.; Lindner, Benjamin

    2017-07-01

    We consider a two-dimensional dynamical system that possesses a heteroclinic orbit connecting four saddle points. This system is not able to show self-sustained oscillations on its own. If endowed with white Gaussian noise it displays stochastic oscillations, the frequency and quality factor of which are controlled by the noise intensity. This stochastic oscillation of a nonlinear system with noise is conveniently characterized by the power spectrum of suitable observables. In this paper we explore different analytical and semianalytical ways to compute such power spectra. Besides a number of explicit expressions for the power spectrum, we find scaling relations for the frequency, spectral width, and quality factor of the stochastic heteroclinic oscillator in the limit of weak noise. In particular, the quality factor shows a slow logarithmic increase with decreasing noise of the form Q˜ [ln (1/D)]^2. Our results are compared to numerical simulations of the respective Langevin equations.

  4. Investigations of the quality of hospital electric power supply and the tolerance of medical electric devices to voltage dips.

    PubMed

    Hanada, Eisuke; Itoga, Shuuya; Takano, Kyoko; Kudou, Takato

    2007-06-01

    Medical devices driven by electric power have come to be commonly used in hospitals, and rapid changes of voltage or current can easily cause them to fail. A stable and high quality power supply is indispensable in order to maintain safety in the modern clinical setting. Therefore, we investigated the quality of the power supply in a hospital and determined the tolerance of 13 pieces of medical equipment to voltage dips. The results showed little distortion of the voltage wave. However, we found an approximately 7% momentary voltage dip caused by lightening and other problems, such as 2 to 5% periodic drops in voltage and voltage wave distortions caused by incorrect grounding. In a tolerance test, the settings of some medical devices were changed at the time of automatic reboot after a disturbance. For another device, trend information was initialized.

  5. The development of enabling technologies for producing active interrogation beams.

    PubMed

    Kwan, Thomas J T; Morgado, Richard E; Wang, Tai-Sen F; Vodolaga, B; Terekhin, V; Onischenko, L M; Vorozhtsov, S B; Samsonov, E V; Vorozhtsov, A S; Alenitsky, Yu G; Perpelkin, E E; Glazov, A A; Novikov, D L; Parkhomchuk, V; Reva, V; Vostrikov, V; Mashinin, V A; Fedotov, S N; Minayev, S A

    2010-10-01

    A U.S./Russian collaboration of accelerator scientists was directed to the development of high averaged-current (∼1 mA) and high-quality (emittance ∼15 πmm mrad; energy spread ∼0.1%) 1.75 MeV proton beams to produce active interrogation beams that could be applied to counterterrorism. Several accelerator technologies were investigated. These included an electrostatic tandem accelerator of novel design, a compact cyclotron, and a storage ring with energy compensation and electron cooling. Production targets capable of withstanding the beam power levels were designed, fabricated, and tested. The cyclotron/storage-ring system was theoretically studied and computationally designed, and the electrostatic vacuum tandem accelerator at BINP was demonstrated for its potential in active interrogation of explosives and special nuclear materials.

  6. The effects of bilateral stimulation of the subthalamic nucleus on heart rate variability in patients with Parkinson's disease.

    PubMed

    Liu, Kang-Du; Shan, Din-E; Kuo, Terry B J; Yang, Cheryl C H

    2013-07-01

    The beneficial effects of subthalamic nucleus deep brain stimulation (STN-DBS) on motor symptoms and quality of life in Parkinson's disease (PD) are well known, but little is known of the effects on autonomic function. Diffusion of current during stimulation of the STN may simultaneously involve the motor and nonmotor, limbic and associative areas of the STN. The aims of this study were to examine whether STN stimulation affects functions of the autonomic nervous system and, if so, to correlate the effects with the active contacts of electrodes in the STN. Eight PD patients with good motor control and quality of sleep after STN-DBS surgery were recruited. All patients had two days of recordings with portable polysomnography (PSG) (first night with stimulation "on" and second night "off"). From the PSG data, the first sleep cycle of each recording night was defined. Heart rate variability (HRV) was analyzed between the same uninterrupted periods of the two sleep nights. In addition, the optimal electrode positions were defined from postoperative MRI studies, and the coordinates of active contacts were confirmed. HRV spectral analysis showed that only low-frequency (LF)/high-frequency (HF) power was significantly activated in the stimulation "on" groups (P = 0.011). There was a significant negative correlation between power change of LF/HF and electrode position lateral to the midcommissural point (ρ = 0.857, P = 0.007) These results demonstrate that STN-DBS can enhance sympathetic regulation; the autonomic response may be due to electrical signals being distributed to limbic components of the STN or descending sympathetic pathways in the zona incerta.

  7. Playing a violent television game affects heart rate variability.

    PubMed

    Ivarsson, Malena; Anderson, Martin; Akerstedt, Torbjörn; Lindblad, Frank

    2009-01-01

    To investigate how playing a violent/nonviolent television game during the evening affects sympathetic and parasympathetic reactions during and after playing as well as sleep quality during the night after playing. In total, 19 boys, 12-15 years of age, played television games on two occasions in their homes and participated once without gaming. Heart rate, heart rate variability (HRV) and physical activity were measured during gaming/participating and the night to follow using a portable combined heart rate and movement sensor. A sleep diary and questionnaires about gaming experiences and session-specific experiences were filled in. Criteria for Selection of Games: Violent game involves/rewards direct physical violence (no handguns) against another person, and nonviolent game involves/rewards no violence; same game design ('third-person game'); conducted in the same manner; no differences concerning motor activity; similar sound and light effects; no sexual content, violence against women or racial overtones. During violent (vs. nonviolent) gaming, there was significantly higher activity of the very low frequency component of the HRV and total power. During the night after playing, very low frequency, low frequency and high frequency components were significantly higher during the violent (vs. nonviolent) condition, just as total power. There were no significant differences between the three conditions (violent/nonviolent/no gaming) with respect to an index reflecting subjectively perceived sleep difficulties. Nor was there any difference between violent and nonviolent condition for any single sleep item. Violent gaming induces different autonomic responses in boys compared to nonviolent gaming--during playing and during the following night--suggesting different emotional responses. Subjectively perceived sleep quality is not influenced after a single gaming experience. Future studies should address the development of the autonomic balance after gaming over longer time than a night, physiological adaptation to frequent gaming and potential gender differences.

  8. Resolution-Enhanced Harmonic and Interharmonic Measurement for Power Quality Analysis in Cyber-Physical Energy System.

    PubMed

    Liu, Yanchi; Wang, Xue; Liu, Youda; Cui, Sujin

    2016-06-27

    Power quality analysis issues, especially the measurement of harmonic and interharmonic in cyber-physical energy systems, are addressed in this paper. As new situations are introduced to the power system, the impact of electric vehicles, distributed generation and renewable energy has introduced extra demands to distributed sensors, waveform-level information and power quality data analytics. Harmonics and interharmonics, as the most significant disturbances, require carefully designed detection methods for an accurate measurement of electric loads whose information is crucial to subsequent analyzing and control. This paper gives a detailed description of the power quality analysis framework in networked environment and presents a fast and resolution-enhanced method for harmonic and interharmonic measurement. The proposed method first extracts harmonic and interharmonic components efficiently using the single-channel version of Robust Independent Component Analysis (RobustICA), then estimates the high-resolution frequency from three discrete Fourier transform (DFT) samples with little additional computation, and finally computes the amplitudes and phases with the adaptive linear neuron network. The experiments show that the proposed method is time-efficient and leads to a better accuracy of the simulated and experimental signals in the presence of noise and fundamental frequency deviation, thus providing a deeper insight into the (inter)harmonic sources or even the whole system.

  9. Resolution-Enhanced Harmonic and Interharmonic Measurement for Power Quality Analysis in Cyber-Physical Energy System

    PubMed Central

    Liu, Yanchi; Wang, Xue; Liu, Youda; Cui, Sujin

    2016-01-01

    Power quality analysis issues, especially the measurement of harmonic and interharmonic in cyber-physical energy systems, are addressed in this paper. As new situations are introduced to the power system, the impact of electric vehicles, distributed generation and renewable energy has introduced extra demands to distributed sensors, waveform-level information and power quality data analytics. Harmonics and interharmonics, as the most significant disturbances, require carefully designed detection methods for an accurate measurement of electric loads whose information is crucial to subsequent analyzing and control. This paper gives a detailed description of the power quality analysis framework in networked environment and presents a fast and resolution-enhanced method for harmonic and interharmonic measurement. The proposed method first extracts harmonic and interharmonic components efficiently using the single-channel version of Robust Independent Component Analysis (RobustICA), then estimates the high-resolution frequency from three discrete Fourier transform (DFT) samples with little additional computation, and finally computes the amplitudes and phases with the adaptive linear neuron network. The experiments show that the proposed method is time-efficient and leads to a better accuracy of the simulated and experimental signals in the presence of noise and fundamental frequency deviation, thus providing a deeper insight into the (inter)harmonic sources or even the whole system. PMID:27355946

  10. Tube focal spot size and power capability impact image quality in the evaluation of intracoronary stents

    NASA Astrophysics Data System (ADS)

    Cesmeli, Erdogan; Berry, Joel L.; Carr, J. J.

    2005-04-01

    Proliferation of coronary stent deployment for treatment of coronary heart disease (CHD) creates a need for imaging-based follow-up examinations to assess patency. Technological improvements in multi-detector computer tomography (MDCT) make it a potential non-invasive alternative to coronary catheterization for evaluation of stent patency; however, image quality with MDCT varies based on the size and composition of the stent. We studied the role of tube focal spot size and power in the optimization of image quality in a stationary phantom. A standard uniform physical phantom with a tubular insert was used where coronary stents (4 mm in diameter) were deployed in a tube filled with contrast to simulate a typical imaging condition observed in clinical practice. We utilized different commercially available stents and scanned them with different tube voltage and current settings (LightSpeed Pro16, GE Healthcare Technologies, Waukesha, WI, USA). The scanner used different focal spot size depending on the power load and thus allowed us to assess the combined effect of the focal spot size and the power. A radiologist evaluated the resulting images in terms of image quality and artifacts. For all stents, we found that the small focal spot size yielded better image quality and reduced artifacts. In general, higher power capability for the given focal spot size improved the signal-to-noise ratio in the images allowing improved assessment. Our preliminary study in a non-moving phantom suggests that a CT scanner that can deliver the same power on a small focal spot size is better suited to have an optimized scan protocol for reliable stent assessment.

  11. Improved power and efficiency for tapered lasers with optimized photonic crystal structures

    NASA Astrophysics Data System (ADS)

    Ma, Xiaolong; Qu, Hongwei; Zhao, Shaoyu; Zhou, Xuyan; Lin, Yuzhe; Zheng, Wanhua

    2017-10-01

    High power and high beam quality laser sources are required in numerous applications such as nonlinear frequency conversion, optical pumping of solid-state and fiber lasers, material processing and others. Tapered lasers can provide a high output power while keeping a high beam quality. However, the conventional tapered lasers suffer from a large vertical beam divergence. We have demonstrated 2-mm long tapered lasers with photonic crystal structures. A high beam quality and a narrow vertical divergence are achieved. In this paper, we optimized the photonic crystal structure and fabricated a 4-mm long tapered laser to further increase the output power and the wall-plug efficiency. Compared with our precious wafer, the optimized structure has a lower doping level to reduce the internal loss. The period of the photonic crystal structure and the thickness of the upper cladding are also reduced. The device has a 1-mm long ridge-waveguide section and a 3-mm long tapered section. The taper angle is 4°. An output power of 7.3 W is achieved with a peak wall-plug efficiency of 46% in continuous-wave mode. The threshold current is around 500 mA and the slope efficiency is 0.93 W/A. In pulsed mode, the output power is 15.6 W and the maximum wall-plug efficiency is 48.1%. The far-field divergence with full width at half maximum is 6.3° for the lateral direction at 3 A. The vertical far-field beam divergence is around 11° at different injection levels. High beam qualities are demonstrated by beam quality factor M2 of 1.52 for the lateral direction and 1.54 for the vertical direction.

  12. Impact of applied ultrasonic power on the low temperature drying of apple.

    PubMed

    Santacatalina, J V; Contreras, M; Simal, S; Cárcel, J A; Garcia-Perez, J V

    2016-01-01

    Low temperature drying (LTD) allows high-quality dried products to be obtained, preserving the nutritional properties of fresh foods better than conventional drying, but it is a time-consuming operation. Power ultrasound (US) could be used to intensify LTD, but it should be taken into account that process variables, such as the level of applied power, have an influence on the magnitude and extension of the ultrasonic effects. Therefore, the aim of this work was to assess the influence of the level of applied ultrasonic power on the LTD of apple, analyzing the drying kinetics and the quality of the dried product. For that purpose, apple (Malus domestica cv. Granny Smith) cubes (8.8mm side) were dried (2m/s) at two different temperatures (10 and -10°C), without and with (25, 50 and 75 W) US application. In the dried apple, the rehydration kinetics, hardness, total phenolic content, antioxidant capacity and microstructure were analyzed to evaluate the impact of the level of applied ultrasonic power. At both temperatures, 10 and -10°C, the higher the ultrasonic power level, the shorter the drying time; the maximum shortening of the drying time achieved was 80.3% (at -10°C and 75 W). The ultrasonic power level did not significantly (p<0.05) affect the quality parameters analyzed. Therefore, US could be considered a non-thermal method of intensifying the LTD of fruits, like apple, with only a mild impact on the quality of the dried product. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Estimation of the antioxidant activity of the commercially available fermented milks.

    PubMed

    Najgebauer-Lejko, Dorota; Sady, Marek

    2015-01-01

    Free radicals are connected with the increased risk of certain diseases, especially cancers. There is some scientific evidence that antioxidant-rich diet may inhibit the negative impact of free radicals. The aim of the present study was to analyse the antioxidant capacity of the selected commercial natural and flavoured fermented milks offered in Poland, derived from different producers. The following commercially available natural fermented milks: 12 yoghurts, 12 kefirs, 2 butter milks, 2 cultured milks, Turkish yoghurt drink (ayran) and the following flavoured fermented milks: 22 yoghurts, 2 acidophillus milks, 2 kefirs, butter milk and vegetable flavoured fermented milk were analysed for their antioxidant potential. The antioxidant capacity was assessed, in two replicates and twice for each product, by means of ferric reducing antioxidant power (FRAP) and DPPH radical scavenging ability (expressed as ARP - anti radical power) methods. Among all analysed plain products, yoghurts and kefirs were characterised by the highest antioxidant activity. The presence of probiotic Lactobacillus casei strains in the product positively affected both FRAP and ARP values. Antioxidant capacity of the flavoured fermented milks was primarily affected by the type and quality (e.g. fruit concentration) of the added flavouring preparation. The most valuable regarding the estimated parameters were chocolate, coffee, grapefruit with green tea extract as well as bilberry, forest fruits, strawberry and cherry with blackcurrant fillings. Protein content, inclusion of probiotic microflora as well as type and quality of flavouring preparations are the main factors affecting antioxidant properties of fermented milks.

  14. Recent Progress on Piezoelectric and Triboelectric Energy Harvesters in Biomedical Systems

    PubMed Central

    Zheng, Qiang; Shi, Bojing; Wang, Zhong Lin

    2017-01-01

    Implantable medical devices (IMDs) have become indispensable medical tools for improving the quality of life and prolonging the patient's lifespan. The minimization and extension of lifetime are main challenges for the development of IMDs. Current innovative research on this topic is focused on internal charging using the energy generated by the physiological environment or natural body activity. To harvest biomechanical energy efficiently, piezoelectric and triboelectric energy harvesters with sophisticated structural and material design have been developed. Energy from body movement, muscle contraction/relaxation, cardiac/lung motions, and blood circulation is captured and used for powering medical devices. Other recent progress in this field includes using PENGs and TENGs for our cognition of the biological processes by biological pressure/strain sensing, or direct intervention of them for some special self‐powered treatments. Future opportunities lie in the fabrication of intelligent, flexible, stretchable, and/or fully biodegradable self‐powered medical systems for monitoring biological signals and treatment of various diseases in vitro and in vivo. PMID:28725529

  15. Automated work packages architecture: An initial set of human factors and instrumentation and controls requirements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Agarwal, Vivek; Oxstrand, Johanna H.; Le Blanc, Katya L.

    The work management process in current fleets of national nuclear power plants is so highly dependent on large technical staffs and quality of work instruction, i.e., paper-based, that this puts nuclear energy at somewhat of a long-term economic disadvantage and increase the possibility of human errors. Technologies like mobile portable devices and computer-based procedures can play a key role in improving the plant work management process, thereby increasing productivity and decreasing cost. Automated work packages are a fundamentally an enabling technology for improving worker productivity and human performance in nuclear power plants work activities because virtually every plant work activitymore » is accomplished using some form of a work package. As part of this year’s research effort, automated work packages architecture is identified and an initial set of requirements identified, that are essential and necessary for implementation of automated work packages in nuclear power plants.« less

  16. Large deflection angle, high-power adaptive fiber optics collimator with preserved near-diffraction-limited beam quality.

    PubMed

    Zhi, Dong; Ma, Yanxing; Chen, Zilun; Wang, Xiaolin; Zhou, Pu; Si, Lei

    2016-05-15

    We report on the development of a monolithic adaptive fiber optics collimator, with a large deflection angle and preserved near-diffraction-limited beam quality, that has been tested at a maximal output power at the 300 W level. Additionally, a new measurement method of beam quality (M2 factor) is developed. Experimental results show that the deflection angle of the collimated beam is in the range of 0-0.27 mrad in the X direction and 0-0.19 mrad in the Y direction. The effective working frequency of the device is about 710 Hz. By employing the new measurement method of the M2 factor, we calculate that the beam quality is Mx2=1.35 and My2=1.24, which is in agreement with the result from the beam propagation analyzer and is preserved well with the increasing output power.

  17. Active pixel sensors: the sensor of choice for future space applications?

    NASA Astrophysics Data System (ADS)

    Leijtens, Johan; Theuwissen, Albert; Rao, Padmakumar R.; Wang, Xinyang; Xie, Ning

    2007-10-01

    It is generally known that active pixel sensors (APS) have a number of advantages over CCD detectors if it comes to cost for mass production, power consumption and ease of integration. Nevertheless, most space applications still use CCD detectors because they tend to give better performance and have a successful heritage. To this respect a change may be at hand with the advent of deep sub-micron processed APS imagers (< 0.25-micron feature size). Measurements performed on test structures at the University of Delft have shown that the imagers are very radiation tolerant even if made in a standard process without the use of special design rules. Furthermore it was shown that the 1/f noise associated with deep sub-micron imagers is reduced as compared to previous generations APS imagers due to the improved quality of the gate oxides. Considering that end of life performance will have to be guaranteed, limited budget for adding shielding metal will be available for most applications and lower power operations is always seen as a positive characteristic in space applications, deep sub-micron APS imagers seem to have a number of advantages over CCD's that will probably cause them to replace CCD's in those applications where radiation tolerance and low power operation are important

  18. IDMA-Based MAC Protocol for Satellite Networks with Consideration on Channel Quality

    PubMed Central

    2014-01-01

    In order to overcome the shortcomings of existing medium access control (MAC) protocols based on TDMA or CDMA in satellite networks, interleave division multiple access (IDMA) technique is introduced into satellite communication networks. Therefore, a novel wide-band IDMA MAC protocol based on channel quality is proposed in this paper, consisting of a dynamic power allocation algorithm, a rate adaptation algorithm, and a call admission control (CAC) scheme. Firstly, the power allocation algorithm combining the technique of IDMA SINR-evolution and channel quality prediction is developed to guarantee high power efficiency even in terrible channel conditions. Secondly, the effective rate adaptation algorithm, based on accurate channel information per timeslot and by the means of rate degradation, can be realized. What is more, based on channel quality prediction, the CAC scheme, combining the new power allocation algorithm, rate scheduling, and buffering strategies together, is proposed for the emerging IDMA systems, which can support a variety of traffic types, and offering quality of service (QoS) requirements corresponding to different priority levels. Simulation results show that the new wide-band IDMA MAC protocol can make accurate estimation of available resource considering the effect of multiuser detection (MUD) and QoS requirements of multimedia traffic, leading to low outage probability as well as high overall system throughput. PMID:25126592

  19. Methods for slow axis beam quality improvement of high power broad area diode lasers

    NASA Astrophysics Data System (ADS)

    An, Haiyan; Xiong, Yihan; Jiang, Ching-Long J.; Schmidt, Berthold; Treusch, Georg

    2014-03-01

    For high brightness direct diode laser systems, it is of fundamental importance to improve the slow axis beam quality of the incorporated laser diodes regardless what beam combining technology is applied. To further advance our products in terms of increased brightness at a high power level, we must optimize the slow axis beam quality despite the far field blooming at high current levels. The later is caused predominantly by the built-in index step in combination with the thermal lens effect. Most of the methods for beam quality improvements reported in publications sacrifice the device efficiency and reliable output power. In order to improve the beam quality as well as maintain the efficiency and reliable output power, we investigated methods of influencing local heat generation to reduce the thermal gradient across the slow axis direction, optimizing the built-in index step and discriminating high order modes. Based on our findings, we have combined different methods in our new device design. Subsequently, the beam parameter product (BPP) of a 10% fill factor bar has improved by approximately 30% at 7 W/emitter without efficiency penalty. This technology has enabled fiber coupled high brightness multi-kilowatt direct diode laser systems. In this paper, we will elaborate on the methods used as well as the results achieved.

  20. An evaluation of helicopter noise and vibration ride qualities criteria

    NASA Technical Reports Server (NTRS)

    Hammond, C. E.; Hollenbaugh, D. D.; Clevenson, S. A.; Leatherwood, J. D.

    1981-01-01

    Two methods of quantifying helicopter ride quality; absorbed power for vibration only and the NASA ride comfort model for both noise and vibration are discussed. Noise and vibration measurements were obtained on five operational US Army helicopters. The data were converted to both absorbed power and DISC's (discomfort units used in the NASA model) for specific helicopter flight conditions. Both models indicate considerable variation in ride quality between the five helicopters and between flight conditions within each helicopter.

  1. Quality Assurance Framework for Mini-Grids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Esterly, Sean; Baring-Gould, Ian; Booth, Samuel

    To address the root challenges of providing quality power to remote consumers through financially viable mini-grids, the Global Lighting and Energy Access Partnership (Global LEAP) initiative of the Clean Energy Ministerial and the U.S. Department of Energy teamed with the National Renewable Energy Laboratory (NREL) and Power Africa to develop a Quality Assurance Framework (QAF) for isolated mini-grids. The framework addresses both alternating current (AC) and direct current (DC) mini-grids, and is applicable to renewable, fossil-fuel, and hybrid systems.

  2. Air quality impacts of projections of natural gas-fired distributed generation

    NASA Astrophysics Data System (ADS)

    Horne, Jeremy R.; Carreras-Sospedra, Marc; Dabdub, Donald; Lemar, Paul; Nopmongcol, Uarporn; Shah, Tejas; Yarwood, Greg; Young, David; Shaw, Stephanie L.; Knipping, Eladio M.

    2017-11-01

    This study assesses the potential impacts on emissions and air quality from the increased adoption of natural gas-fired distributed generation of electricity (DG), including displacement of power from central power generation, in the contiguous United States. The study includes four major tasks: (1) modeling of distributed generation market penetration; (2) modeling of central power generation systems; (3) modeling of spatially and temporally resolved emissions; and (4) photochemical grid modeling to evaluate the potential air quality impacts of increased DG penetration, which includes both power-only DG and combined heat and power (CHP) units, for 2030. Low and high DG penetration scenarios estimate the largest penetration of future DG units in three regions - New England, New York, and California. Projections of DG penetration in the contiguous United States estimate 6.3 GW and 24 GW of market adoption in 2030 for the low DG penetration and high DG penetration scenarios, respectively. High DG penetration (all of which is natural gas-fired) serves to offset 8 GW of new natural gas combined cycle (NGCC) units, and 19 GW of solar photovoltaic (PV) installations by 2030. In all scenarios, air quality in the central United States and the northwest remains unaffected as there is little to no DG penetration in those states. California and several states in the northeast are the most impacted by emissions from DG units. Peak increases in maximum daily 8-h average ozone concentrations exceed 5 ppb, which may impede attainment of ambient air quality standards. Overall, air quality impacts from DG vary greatly based on meteorological conditions, proximity to emissions sources, the number and type of DG installations, and the emissions factors used for DG units.

  3. Power in Practice: Moments of Reflection.

    PubMed

    Karnick, Paula M

    2016-07-01

    Power in practice reveals itself in many ways. There are many definitions of power but in nursing care it could be said that the power is within the patient. Nurses facilitate patients power by engaging them in dialogical engagements. This helps patients to decide how to utilize the power of living their quality. © The Author(s) 2016.

  4. Activities identification for activity-based cost/management applications of the diagnostics outpatient procedures.

    PubMed

    Alrashdan, Abdalla; Momani, Amer; Ababneh, Tamador

    2012-01-01

    One of the most challenging problems facing healthcare providers is to determine the actual cost for their procedures, which is important for internal accounting and price justification to insurers. The objective of this paper is to find suitable categories to identify the diagnostic outpatient medical procedures and translate them from functional orientation to process orientation. A hierarchal task tree is developed based on a classification schema of procedural activities. Each procedure is seen as a process consisting of a number of activities. This makes a powerful foundation for activity-based cost/management implementation and provides enough information to discover the value-added and non-value-added activities that assist in process improvement and eventually may lead to cost reduction. Work measurement techniques are used to identify the standard time of each activity at the lowest level of the task tree. A real case study at a private hospital is presented to demonstrate the proposed methodology. © 2011 National Association for Healthcare Quality.

  5. Kilohertz Pulse Repetition Frequency Slab Ti:sapphire Lasers with High Average Power (10 W)

    NASA Astrophysics Data System (ADS)

    Wadsworth, William J.; Coutts, David W.; Webb, Colin E.

    1999-11-01

    High-average-power broadband 780-nm slab Ti:sapphire lasers, pumped by a kilohertz pulse repetition frequency copper vapor laser (CVL), were demonstrated. These lasers are designed for damage-free power scaling when pumped by CVL s configured for maximum output power (of order 100 W) but with poor beam quality ( M 2 300 ). A simple Brewster-angled slab laser side pumped by a CVL produced 10-W average power (1.25-mJ pulses at 8 kHz) with 4.2-ns FWHM pulse duration at an absolute efficiency of 15% (68-W pump power). Thermal lensing in the Brewster slab laser resulted in multitransverse mode output, and pump absorption was limited to 72% by the maximum doping level for commercially available Ti:sapphire (0.25%). A slab laser with a multiply folded zigzag path was therefore designed and implemented that produced high-beam-quality (TEM 00 -mode) output when operated with cryogenic cooling and provided a longer absorption path for the pump. Excessive scattering of the Ti:sapphire beam at the crystal surfaces limited the efficiency of operation for the zigzag laser, but fluorescence diagnostic techniques, gain measurement, and modeling suggest that efficient power extraction ( 15 W TEM 00 , 23% efficiency) from this laser would be possible for crystals with an optical quality surface polish.

  6. Dynamic power scheduling system for JPEG2000 delivery over wireless networks

    NASA Astrophysics Data System (ADS)

    Martina, Maurizio; Vacca, Fabrizio

    2003-06-01

    Third generation mobile terminals diffusion is encouraging the development of new multimedia based applications. The reliable transmission of audiovisual content will gain major interest being one of the most valuable services. Nevertheless, mobile scenario is severely power constrained: high compression ratios and refined energy management strategies are highly advisable. JPEG2000 as the source encoding stage assures excellent performance with extremely good visual quality. However the limited power budged imposes to limit the computational effort in order to save as much power as possible. Starting from an error prone environment, as the wireless one, high error-resilience features need to be employed. This paper tries to investigate the trade-off between quality and power in such a challenging environment.

  7. Beam control of high-power broad-area photonic crystal lasers using ladderlike groove structure

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Wang, Lijie; Shu, Shili; Tian, Sicong; Lu, Zefeng; Hou, Guanyu; Lu, Huanyu; Tong, Cunzhu; Wang, Lijun

    2017-06-01

    The high-power broad-area (BA) photonic bandgap crystal (PBC) diode laser is promising as a high-brightness laser source, however, it suffers from poor lateral beam quality owing to the intrinsic drawback of BA lasers. In this paper, a ladderlike groove structure (LLGS) was proposed to improve both the lateral beam quality and emission power of BA PBC lasers. An approximately 15.4% improvement in output power and 25.2% decrease in the lateral beam parameter product (BPP) were realized and the underlying mechanism was discussed. On the basis of the one-dimensional PBC epitaxial structure, a stable vertical far field was demonstrated.

  8. ISTC projects devoted to improving laser beam quality

    NASA Astrophysics Data System (ADS)

    Malakhov, Yu. I.

    2007-05-01

    Short overview is done about the activity of ISTC in a direction concerned with improving powerful laser beam quality by means of nonlinear and linear adaptive optics methods. Completed projects #0591 and #1929 resulted in the development of a stimulated Brillouin scattering (SBS) phase conjugation mirror of superhigh fidelity employing the kinoform optical elements (rasters of small lenses) of new generation designed for pulsed or pulse-periodic lasers with nanosecond scale pulse duration. Project #2631 is devoted to development of an adaptive optical system for phase registration and correction of laser beams with wave front vortices. The principles of operation of conventional adaptive systems are based on the assumption that the phase is a smooth continuous function in space. Therefore the solution of the Project tasks will assume a new step in adaptive optics.

  9. Multi-source water pollution in the Upper Citarum watershed, Indonesia, with special reference to its spatiotemporal variation.

    PubMed

    Parikesit; Salim, H; Triharyanto, E; Gunawan, B; Sunardi; Abdoellah, O S; Ohtsuka, R

    2005-01-01

    The Citarum River in West Java is the largest water supplier to the Saguling Dam, which plays a major role in electric power generation for the entire Java Island and is used for the aquaculture of marketed fish. To elucidate the extent of degradation in water quality and its causes in the Upper Citarum watershed, physical, chemical and biological parameters for water samples collected from various sites were analyzed. The results demonstrate large site-to-site variations in water qualities and pollutant loads derived from various human activities such as agriculture, cattle raising and the textile industry. To halt worsening conditions of the Citarum watershed, integrated mitigation efforts should be made, taking biophysical pollution mechanisms and local socioeconomic conditions into account.

  10. 78 FR 7816 - Quality Assurance Program Requirements (Operations)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... NUCLEAR REGULATORY COMMISSION [NRC-2013-0021] Quality Assurance Program Requirements (Operations...), DG-1300, ``Quality Assurance Program Requirements (Operations).'' DATES: Submit comments by April 1... CFR Part 50, Appendix B, ``Quality Assurance Criteria for Nuclear power Plants and Fuel Reprocessing...

  11. Total Quality Education: Profiles of Schools That Demonstrate the Power of Deming's Management Principles.

    ERIC Educational Resources Information Center

    Schmoker, Michael J.; Wilson, Richard B.

    This book presents profiles of schools that have demonstrated the power of Deming's Total Quality Management (TQM) principles. It describes schools that have successfully applied those strategies for change. The book explores what public education needs most--a compelling but flexible action plan for improvement. Chapter 1 offers a rationale for…

  12. Study of ultrasonic melt treatment on the quality of horizontal continuously cast Al-1%Si alloy.

    PubMed

    Li, Xin-Tao; Li, Ting-Ju; Li, Xi-Meng; Jin, Jun-Ze

    2006-02-01

    The fluctuation of the melt temperature in a tundish was measured during casting and experiments were conducted to investigate the effects of ultrasonic melt treatment on the surface quality and solidification structures of Al-1%Si ingots. The results show that the uniformity of melt temperature was enhanced with the application of ultrasonic melt treatment. When the ultrasonic power is 1,000W, the surface quality was evidently improved and grains of cast ingots were refined. Moreover, EPMA analysis was adopted to study the relationship between the ultrasonic power and boundary segregation of Si element. The result shows that boundary segregation is suppressed with the increase of ultrasonic power and the phenomenon was theoretically interpreted.

  13. Yb3+-doped rod-type amplifiers with local adiabatic tapers for peak power scaling and beam quality improvement

    NASA Astrophysics Data System (ADS)

    Zhu, Yuan; Eschrich, Tina; Leich, Martin; Grimm, Stephan; Kobelke, Jens; Lorenz, Martin; Bartelt, Hartmut; Jäger, Matthias

    2017-10-01

    The use of short local tapers in large mode area fiber amplifiers is proposed for peak power scaling while maintaining good beam quality. To avoid modal distortions, the powder-sintering (REPUSIL) method was employed to obtain core materials with excellent refractive index homogeneity. First experiments with Yb3+-doped rod-type amplifiers delivered 2 ns pulses with peak powers of 540 kW and energies of 1.4 mJ for the untapered rod and 230 kW for the tapered rod (limited by facet damage). The beam quality improved from an M 2 value of approximately 10 to 3.5. The investigation of the taper structure indicates room for further improvement.

  14. 970-nm ridge waveguide diode laser bars for high power DWBC systems

    NASA Astrophysics Data System (ADS)

    Wilkens, Martin; Erbert, Götz; Wenzel, Hans; Knigge, Andrea; Crump, Paul; Maaßdorf, Andre; Fricke, Jörg; Ressel, Peter; Strohmaier, Stephan; Schmidt, Berthold; Tränkle, Günther

    2018-02-01

    de lasers are key components in material processing laser systems. While mostly used as pump sources for solid state or fiber lasers, direct diode laser systems using dense wavelength multiplexing have come on the market in recent years. These systems are realized with broad area lasers typically, resulting in beam quality inferior to disk or fiber lasers. We will present recent results of highly efficient ridge waveguide (RW) lasers, developed for dense-wavelength-beamcombining (DWBC) laser systems expecting beam qualities comparable to solid state laser systems and higher power conversion efficiencies (PCE). The newly developed RW lasers are based on vertical structures with an extreme double asymmetric large optical cavity. Besides a low vertical divergence these structures are suitable for RW-lasers with (10 μm) broad ridges, emitting in a single mode with a good beam quality. The large stripe width enables a lateral divergence below 10° (95 % power content) and a high PCE by a comparably low series resistance. We present results of single emitters and small test arrays under different external feedback conditions. Single emitters can be tuned from 950 nm to 975 nm and reach 1 W optical power with more than 55 % PCE and a beam quality of M2 < 2 over the full wavelength range. The spectral width is below 30 pm FWHM. 5 emitter arrays were stabilized using the same setup. Up to now we reached 3 W optical power, limited by power supply, with 5 narrow spectral lines.

  15. Mercury Information Clearinghouse

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chad A. Wocken; Michael J. Holmes; Dennis L. Laudal

    2006-03-31

    The Canadian Electricity Association (CEA) identified a need and contracted the Energy & Environmental Research Center (EERC) to create and maintain an information clearinghouse on global research and development activities related to mercury emissions from coal-fired electric utilities. With the support of CEA, the Center for Air Toxic Metals{reg_sign} (CATM{reg_sign}) Affiliates, and the U.S. Department of Energy (DOE), the EERC developed comprehensive quarterly information updates that provide a detailed assessment of developments in the various areas of mercury monitoring, control, policy, and research. A total of eight topical reports were completed and are summarized and updated in this final CEAmore » quarterly report. The original quarterly reports can be viewed at the CEA Web site (www.ceamercuryprogram.ca). In addition to a comprehensive update of previous mercury-related topics, a review of results from the CEA Mercury Program is provided. Members of Canada's coal-fired electricity generation sector (ATCO Power, EPCOR, Manitoba Hydro, New Brunswick Power, Nova Scotia Power Inc., Ontario Power Generation, SaskPower, and TransAlta) and CEA, have compiled an extensive database of information from stack-, coal-, and ash-sampling activities. Data from this effort are also available at the CEA Web site and have provided critical information for establishing and reviewing a mercury standard for Canada that is protective of environment and public health and is cost-effective. Specific goals outlined for the CEA mercury program included the following: (1) Improve emission inventories and develop management options through an intensive 2-year coal-, ash-, and stack-sampling program; (2) Promote effective stack testing through the development of guidance material and the support of on-site training on the Ontario Hydro method for employees, government representatives, and contractors on an as-needed basis; (3) Strengthen laboratory analytical capabilities through analysis and quality assurance programs; and (4) Create and maintain an information clearinghouse to ensure that all parties can keep informed on global mercury research and development activities.« less

  16. High-power narrow-linewidth quasi-CW diode-pumped TEM00 1064 nm Nd:YAG ring laser.

    PubMed

    Liu, Yuan; Wang, Bao-shan; Xie, Shi-yong; Bo, Yong; Wang, Peng-yuan; Zuo, Jun-wei; Xu, Yi-ting; Xu, Jia-lin; Peng, Qin-jun; Cui, Da-fu; Xu, Zu-yan

    2012-04-01

    We demonstrated a high average power, narrow-linewidth, quasi-CW diode-pumped Nd:YAG 1064 nm laser with near-diffraction-limited beam quality. A symmetrical three-mirror ring cavity with unidirectional operation elements and an etalon was employed to realize the narrow-linewidth laser output. Two highly efficient laser modules and a 90° quartz rotator for birefringence compensation were used for the high output power. The maximum average output power of 62.5 W with the beam quality factor M(2) of 1.15 was achieved under a pump power of 216 W at a repetition rate of 500 Hz, corresponding to the optical-to-optical conversion efficiency of 28.9%. The linewidth of the laser at the maximum output power was measured to be less than 0.2 GHz.

  17. The effect of obesity on the contractile performance of isolated mouse soleus, EDL, and diaphragm muscles.

    PubMed

    Tallis, Jason; Hill, Cameron; James, Rob S; Cox, Val M; Seebacher, Frank

    2017-01-01

    Obesity affects the major metabolic and cellular processes involved in skeletal muscle contractility. Surprisingly, the effect of obesity on isolated skeletal muscle performance remains unresolved. The present study is the first to examine the muscle-specific changes in contractility following dietary-induced obesity using an isolated muscle work-loop (WL) model that more closely represents in vivo muscle performance. Following 16-wk high-calorific feeding, soleus (SOL), extensor digitorum longus (EDL), and diaphragm (DIA) were isolated from female (CD-1) mice, and contractile performance was compared against a lean control group. Obese SOL produced greater isometric force; however, isometric stress (force per unit muscle area), absolute WL power, and normalized WL power (watts per kilogram muscle mass) were unaffected. Maximal isometric force and absolute WL power of the EDL were similar between groups. For both EDL and DIA, isometric stress and normalized WL power were reduced in the obese groups. Obesity caused a significant reduction in fatigue resistance in all cases. Our findings demonstrate a muscle-specific reduction in contractile performance and muscle quality that is likely related to in vivo mechanical role, fiber type, and metabolic profile, which may in part be related to changes in myosin heavy chain expression and AMP-activated protein kinase activity. These results infer that, beyond the additional requirement of moving a larger body mass, functional performance and quality of life may be further limited by poor muscle function in obese individuals. As such, a reduction in muscle performance may be a substantial contributor to the negative cycle of obesity. The effect of obesity on isolated muscle function is surprisingly underresearched. The present study is the first to examine the effects of obesity on isolated muscle performance using a method that more closely represents real-world muscle function. This work uniquely establishes a muscle-specific profile of mechanical changes in relation to underpinning mechanisms. These findings may be important to understanding the negative cycle of obesity and in designing interventions for improving weight status. Copyright © 2017 the American Physiological Society.

  18. 18 CFR 801.7 - Water quality.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... water quality management and control. However, protection of the water resources of the basin from... quality program in the comprehensive plan. (c) The Commission's role in water quality management and... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Water quality. 801.7...

  19. Denervation-Induced Activation of the Ubiquitin-Proteasome System Reduces Skeletal Muscle Quantity Not Quality.

    PubMed

    Baumann, Cory W; Liu, Haiming M; Thompson, LaDora V

    2016-01-01

    It is well known that the ubiquitin-proteasome system is activated in response to skeletal muscle wasting and functions to degrade contractile proteins. The loss of these proteins inevitably reduces skeletal muscle size (i.e., quantity). However, it is currently unknown whether activation of this pathway also affects function by impairing the muscle's intrinsic ability to produce force (i.e., quality). Therefore, the purpose of this study was twofold, (1) document how the ubiquitin-proteasome system responds to denervation and (2) identify the physiological consequences of these changes. To induce soleus muscle atrophy, C57BL6 mice underwent tibial nerve transection of the left hindlimb for 7 or 14 days (n = 6-8 per group). At these time points, content of several proteins within the ubiquitin-proteasome system were determined via Western blot, while ex vivo whole muscle contractility was specifically analyzed at day 14. Denervation temporarily increased several key proteins within the ubiquitin-proteasome system, including the E3 ligase MuRF1 and the proteasome subunits 19S, α7 and β5. These changes were accompanied by reductions in absolute peak force and power, which were offset when expressed relative to physiological cross-sectional area. Contrary to peak force, absolute and relative forces at submaximal stimulation frequencies were significantly greater following 14 days of denervation. Taken together, these data represent two keys findings. First, activation of the ubiquitin-proteasome system is associated with reductions in skeletal muscle quantity rather than quality. Second, shortly after denervation, it appears the muscle remodels to compensate for the loss of neural activity via changes in Ca2+ handling.

  20. A Metric-Based Validation Process to Assess the Realism of Synthetic Power Grids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Birchfield, Adam; Schweitzer, Eran; Athari, Mir

    Public power system test cases that are of high quality benefit the power systems research community with expanded resources for testing, demonstrating, and cross-validating new innovations. Building synthetic grid models for this purpose is a relatively new problem, for which a challenge is to show that created cases are sufficiently realistic. This paper puts forth a validation process based on a set of metrics observed from actual power system cases. These metrics follow the structure, proportions, and parameters of key power system elements, which can be used in assessing and validating the quality of synthetic power grids. Though wide diversitymore » exists in the characteristics of power systems, the paper focuses on an initial set of common quantitative metrics to capture the distribution of typical values from real power systems. The process is applied to two new public test cases, which are shown to meet the criteria specified in the metrics of this paper.« less

  1. A Metric-Based Validation Process to Assess the Realism of Synthetic Power Grids

    DOE PAGES

    Birchfield, Adam; Schweitzer, Eran; Athari, Mir; ...

    2017-08-19

    Public power system test cases that are of high quality benefit the power systems research community with expanded resources for testing, demonstrating, and cross-validating new innovations. Building synthetic grid models for this purpose is a relatively new problem, for which a challenge is to show that created cases are sufficiently realistic. This paper puts forth a validation process based on a set of metrics observed from actual power system cases. These metrics follow the structure, proportions, and parameters of key power system elements, which can be used in assessing and validating the quality of synthetic power grids. Though wide diversitymore » exists in the characteristics of power systems, the paper focuses on an initial set of common quantitative metrics to capture the distribution of typical values from real power systems. The process is applied to two new public test cases, which are shown to meet the criteria specified in the metrics of this paper.« less

  2. An Energy Saving Green Plug Device for Nonlinear Loads

    NASA Astrophysics Data System (ADS)

    Bloul, Albe; Sharaf, Adel; El-Hawary, Mohamed

    2018-03-01

    The paper presents a low cost a FACTS Based flexible fuzzy logic based modulated/switched tuned arm filter and Green Plug compensation (SFC-GP) scheme for single-phase nonlinear loads ensuring both voltage stabilization and efficient energy utilization. The new Green Plug-Switched filter compensator SFC modulated LC-Filter PWM Switched Capacitive Compensation Devices is controlled using a fuzzy logic regulator to enhance power quality, improve power factor at the source and reduce switching transients and inrush current conditions as well harmonic contents in source current. The FACTS based SFC-GP Device is a member of family of Green Plug/Filters/Compensation Schemes used for efficient energy utilization, power quality enhancement and voltage/inrush current/soft starting control using a dynamic error driven fuzzy logic controller (FLC). The device with fuzzy logic controller is validated using the Matlab / Simulink Software Environment for enhanced power quality (PQ), improved power factor and reduced inrush currents. This is achieved using modulated PWM Switching of the Filter-Capacitive compensation scheme to cope with dynamic type nonlinear and inrush cyclical loads..

  3. A low-power and high-quality implementation of the discrete cosine transformation

    NASA Astrophysics Data System (ADS)

    Heyne, B.; Götze, J.

    2007-06-01

    In this paper a computationally efficient and high-quality preserving DCT architecture is presented. It is obtained by optimizing the Loeffler DCT based on the Cordic algorithm. The computational complexity is reduced from 11 multiply and 29 add operations (Loeffler DCT) to 38 add and 16 shift operations (which is similar to the complexity of the binDCT). The experimental results show that the proposed DCT algorithm not only reduces the computational complexity significantly, but also retains the good transformation quality of the Loeffler DCT. Therefore, the proposed Cordic based Loeffler DCT is especially suited for low-power and high-quality CODECs in battery-based systems.

  4. 78 FR 37850 - Quality Assurance Program Requirements (Operations)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-24

    ... NUCLEAR REGULATORY COMMISSION [NRC-2013-0021] Quality Assurance Program Requirements (Operations... Regulatory Commission (NRC) is issuing a revision to Regulatory Guide (RG) 1.33, ``Quality Assurance Program... managerial and administrative Quality Assurance (QA) controls for nuclear power plants during operations...

  5. [Restoration of speech function in oncological patients with maxillary defects].

    PubMed

    Matiakin, E G; Chuchkov, V M; Akhundov, A A; Azizian, R I; Romanov, I S; Chuchkov, M V; Agapov, V V

    2009-01-01

    Speech quality was evaluated in 188 patients with acquired maxillary defects. Prosthetic treatment of 29 patients was preceded by pharmacopsychotherapy. Sixty three patients had lessons with a logopedist and 66 practiced self-tuition based on the specially developed test. Thirty patients were examined for the quality of speech without preliminary preparation. Speech quality was assessed by auditory and spectral analysis. The main forms of impaired speech quality in the patients with maxillary defects were marked rhinophonia and impaired articulation. The proposed analytical tests were based on a combination of "difficult" vowels and consonants. The use of a removable prostheses with an obturator failed to correct the affected speech function but created prerequisites for the formation of the correct speech stereotype. Results of the study suggest the relationship between the quality of speech in subjects with maxillary defects and their intellectual faculties as well as the desire to overcome this drawback. The proposed tests are designed to activate the neuromuscular apparatus responsible for the generation of the speech. Lessons with a speech therapist give a powerful emotional incentive to the patients and promote their efforts toward restoration of speaking ability. Pharmacopsychotherapy and self-control are another efficacious tools for the improvement of speech quality in patients with maxillary defects.

  6. Therapeutic effects of short-term monochromatic infrared energy therapy on patients with knee osteoarthritis: a double-blind, randomized, placebo-controlled study.

    PubMed

    Hsieh, Ru-Lan; Lo, Min-Tzu; Lee, Wen-Chung; Liao, Wei-Cheng

    2012-11-01

    Randomized, double-blind, placebo-controlled study. To examine the short-term therapeutic effects of monochromatic infrared energy (MIRE) on participants with knee osteoarthritis (OA). Patients were assessed according to the International Classification of Functioning, Disability and Health. MIRE is commonly used in therapy for patients with peripheral neuropathies. However, research has not focused intensively on the therapeutic effects of MIRE in patients with knee OA. This study enrolled 73 participants with knee OA. Participants received six 40-minute sessions of active or placebo MIRE treatment (890-nm wavelength; power, 6.24 W; energy density, 2.08 J/cm2/min; total energy, 83.2 J/cm2) over the knee joints for 2 weeks. International Classification of Functioning, Disability and Health-related outcomes were collected weekly over 4 weeks using the Knee injury and Osteoarthritis Outcome Score, Lysholm Knee Scale, Hospital Anxiety and Depression Scale, Multidimensional Fatigue Inventory, Chronic Pain Grade questionnaire, World Health Organization Quality of Life-brief version, and OA Quality of Life Questionnaire. Data were analyzed by repeated-measures analysis of variance. No statistically significant differences were found for the interaction of group by time for Knee injury and Osteoarthritis Outcome Score scores, including pain, other symptoms, function in daily living, function in sport and recreation, and knee-related quality of life. Scores on the Lysholm Knee Scale, Hospital Anxiety and Depression Scale, Multidimensional Fatigue Inventory, Chronic Pain Grade questionnaire, World Health Organization Quality of Life-brief version, and OA Quality of Life Questionnaire also showed no significant differences between the 2 groups at any of the 4 follow-up assessments. Short-term MIRE therapy provided no beneficial effects to body functions, activities, participation, and quality of life in patients with knee OA.

  7. Influence of fossil-fuel power plant emissions on the surface fine particulate matter in the Seoul Capital Area, South Korea.

    PubMed

    Kim, Byeong-Uk; Kim, Okgil; Kim, Hyun Cheol; Kim, Soontae

    2016-09-01

    The South Korean government plans to reduce region-wide annual PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm) concentrations in the Seoul Capital Area (SCA) from 2010 levels of 27 µg/m(3) to 20 µg/m(3) by 2024. At the same time, it is inevitable that emissions from fossil-fuel power plants will continue to increase if electricity generation expands and the generation portfolio remains the same in the future. To estimate incremental PM2.5 contributions due to projected electricity generation growth in South Korea, we utilized an ensemble forecasting member of the Integrated Multidimensional Air Quality System for Korea based on the Community Multi-scale Air Quality model. We performed sensitivity runs with across-the-board emission reductions for all fossil-fuel power plants in South Korea to estimate the contribution of PM2.5 from domestic fossil-fuel power plants. We estimated that fossil-fuel power plants are responsible for 2.4% of the annual PM2.5 national ambient air quality standard in the SCA as of 2010. Based on the electricity generation and the annual contribution of fossil-fuel power plants in 2010, we estimated that annual PM2.5 concentrations may increase by 0.2 µg/m(3) per 100 TWhr due to additional electricity generation. With currently available information on future electricity demands, we estimated that the total future contribution of fossil-fuel power plants would be 0.87 µg/m(3), which is 12.4% of the target reduction amount of the annual PM2.5 concentration by 2024. We also approximated that the number of premature deaths caused by existing fossil-fuel power plants would be 736 in 2024. Since the proximity of power plants to the SCA and the types of fuel used significantly impact this estimation, further studies are warranted on the impact of physical parameters of plants, such as location and stack height, on PM2.5 concentrations in the SCA due to each precursor. Improving air quality by reducing fine particle pollution is challenging when fossil-fuel-based electricity production is increasing. We show that an air quality forecasting system based on a photochemical model can be utilized to efficiently estimate PM2.5 contributions from and health impacts of domestic power plants. We derived PM2.5 concentrations per unit amount of electricity production from existing fossil-fuel power plants in South Korea. We assessed the health impacts of existing fossil-fuel power plants and the PM2.5 concentrations per unit electricity production to quantify the significance of existing and future fossil-fuel power plants with respect to the planned PM2.5 reduction target.

  8. Overview of Power Quality and Integrated Testing at JSC

    NASA Technical Reports Server (NTRS)

    Davies, Francis

    2018-01-01

    This presentation describes the basic philosophy behind integrated testing and partially integrated testing. It lists some well known errors in space systems that were or could have been caught during integrated testing. Two examples of integrated testing at the Johnson Space Center (JSC) are mentioned, and then an overview of two test facilities that do power testing (partially integrated testing) at JSC are presented, with information on the capabilities of each. Finally a list of three projects that has problems caught during power quality or Electromagnetic Interference (EMI) testing is presented.

  9. Power distance and mentor-protégé relationship quality as moderators of the relationship between informal mentoring and burnout: evidence from China.

    PubMed

    Qian, Jing; Han, Zhuo; Wang, Haiwan; Li, Xiaoyan; Wang, Qiuyue

    2014-01-01

    The topic of how to prevent and reduce burnout has drawn great attention from researchers and practitioners in recent years. However, we know little about how mentoring as a form of social support exerts influence on employee burnout. This study aims to examine the contingency side of the mentoring-burnout relationship by addressing the exploratory question of whether individual differences in power distance and relationship quality play important roles in mentoring effectiveness in terms of reducing a protégé's burnout level. A total of 210 employees from a technology communications company completed the survey questionnaire. (1) A protégés' power distance moderates the negative relationship between mentoring and burnout in such a way that the relationship is stronger for protégés who are lower rather than higher in power distance; (2) mentor-protégé relationship quality moderates the negative relationship between mentoring and burnout in such a way that the relationship is stronger when the relationship quality is higher rather than lower. In sum, our results highlight the importance of studying the contingency side of mentoring effects on protégé burnout. Our findings suggest that the individuals' different cultural values of power distance and mentor-protégé relationship quality are the boundary conditions for the mentoring-burnout relationship. We therefore suggest that research on mentoring-burnout will be advanced by considering the role of the moderating process.

  10. Power analysis and trend detection for water quality monitoring data. An application for the Greater Yellowstone Inventory and Monitoring Network

    USGS Publications Warehouse

    Irvine, Kathryn M.; Manlove, Kezia; Hollimon, Cynthia

    2012-01-01

    An important consideration for long term monitoring programs is determining the required sampling effort to detect trends in specific ecological indicators of interest. To enhance the Greater Yellowstone Inventory and Monitoring Network’s water resources protocol(s) (O’Ney 2006 and O’Ney et al. 2009 [under review]), we developed a set of tools to: (1) determine the statistical power for detecting trends of varying magnitude in a specified water quality parameter over different lengths of sampling (years) and different within-year collection frequencies (monthly or seasonal sampling) at particular locations using historical data, and (2) perform periodic trend analyses for water quality parameters while addressing seasonality and flow weighting. A power analysis for trend detection is a statistical procedure used to estimate the probability of rejecting the hypothesis of no trend when in fact there is a trend, within a specific modeling framework. In this report, we base our power estimates on using the seasonal Kendall test (Helsel and Hirsch 2002) for detecting trend in water quality parameters measured at fixed locations over multiple years. We also present procedures (R-scripts) for conducting a periodic trend analysis using the seasonal Kendall test with and without flow adjustment. This report provides the R-scripts developed for power and trend analysis, tutorials, and the associated tables and graphs. The purpose of this report is to provide practical information for monitoring network staff on how to use these statistical tools for water quality monitoring data sets.

  11. Power Quality and Reliability Project

    NASA Technical Reports Server (NTRS)

    Attia, John O.

    2001-01-01

    One area where universities and industry can link is in the area of power systems reliability and quality - key concepts in the commercial, industrial and public sector engineering environments. Prairie View A&M University (PVAMU) has established a collaborative relationship with the University of'Texas at Arlington (UTA), NASA/Johnson Space Center (JSC), and EP&C Engineering and Technology Group (EP&C) a small disadvantage business that specializes in power quality and engineering services. The primary goal of this collaboration is to facilitate the development and implementation of a Strategic Integrated power/Systems Reliability and Curriculum Enhancement Program. The objectives of first phase of this work are: (a) to develop a course in power quality and reliability, (b) to use the campus of Prairie View A&M University as a laboratory for the study of systems reliability and quality issues, (c) to provide students with NASA/EPC shadowing and Internship experience. In this work, a course, titled "Reliability Analysis of Electrical Facilities" was developed and taught for two semesters. About thirty seven has benefited directly from this course. A laboratory accompanying the course was also developed. Four facilities at Prairie View A&M University were surveyed. Some tests that were performed are (i) earth-ground testing, (ii) voltage, amperage and harmonics of various panels in the buildings, (iii) checking the wire sizes to see if they were the right size for the load that they were carrying, (iv) vibration tests to test the status of the engines or chillers and water pumps, (v) infrared testing to the test arcing or misfiring of electrical or mechanical systems.

  12. Recent experience with the CQE{trademark}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harrison, C.D.; Kehoe, D.B.; O`Connor, D.C.

    1997-12-31

    CQE (the Coal Quality Expert) is a software tool that brings a new level of sophistication to fuel decisions by seamlessly integrating the system-wide effects of fuel purchase decisions on power plant performance, emissions, and power generation costs. The CQE technology, which addresses fuel quality from the coal mine to the busbar and the stack, is an integration and improvement of predecessor software tools including: EPRI`s Coal Quality Information System, EPRI`s Coal Cleaning Cost Model, EPRI`s Coal Quality Impact Model, and EPRI and DOE models to predict slagging and fouling. CQE can be used as a stand-alone workstation or asmore » a network application for utilities, coal producers, and equipment manufacturers to perform detailed analyses of the impacts of coal quality, capital improvements, operational changes, and/or environmental compliance alternatives on power plant emissions, performance and production costs. It can be used as a comprehensive, precise and organized methodology for systematically evaluating all such impacts or it may be used in pieces with some default data to perform more strategic or comparative studies.« less

  13. The climate and air-quality benefits of wind and solar power in the United States

    NASA Astrophysics Data System (ADS)

    Millstein, Dev; Wiser, Ryan; Bolinger, Mark; Barbose, Galen

    2017-09-01

    Wind and solar energy reduce combustion-based electricity generation and provide air-quality and greenhouse gas emission benefits. These benefits vary dramatically by region and over time. From 2007 to 2015, solar and wind power deployment increased rapidly while regulatory changes and fossil fuel price changes led to steep cuts in overall power-sector emissions. Here we evaluate how wind and solar climate and air-quality benefits evolved during this time period. We find cumulative wind and solar air-quality benefits of 2015 US$29.7-112.8 billion mostly from 3,000 to 12,700 avoided premature mortalities, and cumulative climate benefits of 2015 US$5.3-106.8 billion. The ranges span results across a suite of air-quality and health impact models and social cost of carbon estimates. We find that binding cap-and-trade pollutant markets may reduce these cumulative benefits by up to 16%. In 2015, based on central estimates, combined marginal benefits equal 7.3 ¢ kWh-1 (wind) and 4.0 ¢ kWh-1 (solar).

  14. A home-based exercise program to improve function, fatigue, and sleep quality in patients with Stage IV lung and colorectal cancer: a randomized controlled trial.

    PubMed

    Cheville, Andrea L; Kollasch, Jenny; Vandenberg, Justin; Shen, Tiffany; Grothey, Axel; Gamble, Gail; Basford, Jeffrey R

    2013-05-01

    Exercise benefits patients with cancer, but studies of home-based approaches, particularly among those with Stage IV disease, remain small and exploratory. To conduct an adequately powered trial of a home-based exercise intervention that can be facilely integrated into established delivery and reimbursement structures. Sixty-six adults with Stage IV lung or colorectal cancer were randomized, in an eight-week trial, to usual care or incremental walking and home-based strength training. The exercising participants were instructed during a single physiotherapy visit and subsequently exercised four days or more per week; training and step-count goals were advanced during bimonthly telephone calls. The primary outcome measure was mobility assessed with the Ambulatory Post Acute Care Basic Mobility Short Form. Secondary outcomes included ratings of pain and sleep quality as well as the ability to perform daily activities (Ambulatory Post Acute Care Daily Activities Short Form), quality of life (Functional Assessment of Cancer Therapy-General), and fatigue (Functional Assessment of Cancer Therapy-Fatigue). Three participants dropped out and seven died (five in the intervention and two in the control group, P=0.28). At Week 8, the intervention group reported improved mobility (P=0.01), fatigue (P=0.02), and sleep quality (P=0.05) compared with the usual care group, but did not differ on the other measures. A home-based exercise program seems capable of improving the mobility, fatigue, and sleep quality of patients with Stage IV lung and colorectal cancer. Copyright © 2013. Published by Elsevier Inc.

  15. Optical communication for space missions

    NASA Technical Reports Server (NTRS)

    Firtmaurice, M.

    1991-01-01

    Activities performed at NASA/GSFC (Goddard Space Flight Center) related to direct detection optical communications for space applications are discussed. The following subject areas are covered: (1) requirements for optical communication systems (data rates and channel quality; spatial acquisition; fine tracking and pointing; and transmit point-ahead correction); (2) component testing and development (laser diodes performance characterization and life testing; and laser diode power combining); (3) system development and simulations (The GSFC pointing, acquisition and tracking system; hardware description; preliminary performance analysis; and high data rate transmitter/receiver systems); and (4) proposed flight demonstration of optical communications.

  16. Spinal Cord Injuries in Wave-Riding Sports: The Influence of Environmental and Sport-Specific Factors.

    PubMed

    Falconi, Audrey; Flick, David; Ferguson, Jason; Glorioso, John E

    2016-01-01

    Spinal cord injury is a nonfatal, catastrophic consequence of wave-riding sports. With surfing at the core, a multitude of activities have evolved that attempt to harness the power of ocean waves. The unique qualities of each wave-riding sport, in combination with the environmental factors of the ocean, define the risk for potential injuries. As wave-riding sports have become more advanced, athletes continue to push physical barriers. Taller waves are attempted while incorporating aerial maneuvers, all without protective equipment.

  17. SMART-FDIR: Use of Artificial Intelligence in the Implementation of a Satellite FDIR

    NASA Astrophysics Data System (ADS)

    Guiotto, A.; Martelli, A.; Paccagnini, C.

    Nowadays space activities are characterized by increased constraints in terms of on-board computing power and functional complexity combined with reduction of costs and schedule. This scenario necessarily originates impacts on the on-board software with particular emphases to the interfaces between on-board software and system/mission level requirements. The questions are: How can the effectiveness of Space System Software design be improved? How can we increase sophistication in the area of autonomy and failure tolerance, maintaining the necessary quality with acceptable risks?

  18. Dependence of the quality of adhesion between poly(dimethylsiloxane) and glass surfaces on the conditions of treatment with oxygen plasma.

    PubMed

    Millare, Brent; Thomas, Marlon; Ferreira, Amy; Xu, Hong; Holesinger, Madison; Vullev, Valentine I

    2008-11-18

    Treatment with oxygen-containing plasma is an essential step for the fabrication of devices containing components of polydimethylsiloxane (PDMS). Such oxidative treatment chemically modifies the surface of PDMS allowing it to permanently adhere to glass, quartz, PDMS and other silica-based substrates. Overexposure of PDMS to oxidative gas plasma, however, compromises its adhesiveness. Therefore, regulation of the duration and the conditions of the plasma treatment is crucial for achieving sufficient surface activation without overoxidation. Using a semiquantitative ternary approach, we evaluated the quality of adhesion ( QA) between flat PDMS and glass substrates pretreated with oxygen plasma under a range of different conditions. The quality of adhesion manifested good correlation trends with the surface properties of the pretreated PDMS. Examination of the QA dependence on the treatment duration and on the pressure and the RF power of the plasma revealed a range of oxidative conditions that allowed for permanent adhesion with quantitative yields.

  19. Applications of Wavelet Transform and Fuzzy Neural Network on Power Quality Recognition

    NASA Astrophysics Data System (ADS)

    Liao, Chiung-Chou; Yang, Hong-Tzer; Lin, Ying-Chun

    2008-10-01

    The wavelet transform coefficients (WTCs) contain plenty of information needed for transient event identification of power quality (PQ) events. However, adopting WTCs directly has the drawbacks of taking a longer time and too much memory for the recognition system. To solve the abovementioned recognition problems and to effectively reduce the number of features representing power transients, spectrum energies of WTCs in different scales are calculated by Parseval's Theorem. Through the proposed approach, features of the original power signals can be reserved and not influenced by occurring points of PQ events. The fuzzy neural classification systems are then used for signal recognition and fuzzy rule construction. Success rates of recognizing PQ events from noise-riding signals are proven to be feasible in power system applications in this paper.

  20. Sound Arguments and Power in Evaluation Research and Policy-Making: A Measuring Instrument and Its Application.

    ERIC Educational Resources Information Center

    Propper, Igno M. A. M.

    1993-01-01

    Proposes an instrument for assessing the extent to which either sound arguments or power are found in scientific and political discussions. Empirical research is described that investigated the relation between the quality of evaluation research and the quality of discussion in policy-making processes in which the research is used. (Contains 47…

  1. Social Power: Effect on Spouses' Quality of Personal Life.

    ERIC Educational Resources Information Center

    Thomas, Cher Carrie

    It is the dimension of power or control, either in the workplace or in the family, that determines the degree to which social relations are alienating. The consequences of social inequality for the quality of personal life were examined in 314 married couples, of whom 70 were dual-earning non-parents, 123 were dual-earning parents, and 41 were…

  2. Assessing I-Grid(TM) web-based monitoring for power quality and reliability benchmarking

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Divan, Deepak; Brumsickle, William; Eto, Joseph

    2003-04-30

    This paper presents preliminary findings from DOEs pilot program. The results show how a web-based monitoring system can form the basis for aggregation of data and correlation and benchmarking across broad geographical lines. A longer report describes additional findings from the pilot, including impacts of power quality and reliability on customers operations [Divan, Brumsickle, Eto 2003].

  3. 18 CFR 410.1 - Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations. 410.1 Section 410.1 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS; WATER CODE AND ADMINISTRATIVE MANUAL-PART III...

  4. 18 CFR 410.1 - Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations. 410.1 Section 410.1 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS; WATER CODE AND ADMINISTRATIVE MANUAL-PART III...

  5. 18 CFR 410.1 - Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations. 410.1 Section 410.1 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS; WATER CODE AND ADMINISTRATIVE MANUAL-PART III...

  6. 18 CFR 410.1 - Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Basin regulations-Water Code and Administrative Manual-Part III Water Quality Regulations. 410.1 Section 410.1 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS; WATER CODE AND ADMINISTRATIVE MANUAL-PART III...

  7. Power Quality Improvement Utilizing Photovoltaic Generation Connected to a Weak Grid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muljadi, Eduard; Tumbelaka, Hanny H.; Gao, Wenzhong

    Microgrid research and development in the past decades have been one of the most popular topics. Similarly, the photovoltaic generation has been surging among renewable generation in the past few years, thanks to the availability, affordability, technology maturity of the PV panels and the PV inverter in the general market. Unfortunately, quite often, the PV installations are connected to weak grids and may have been considered as the culprit of poor power quality affecting other loads in particular sensitive loads connected to the same point of common coupling (PCC). This paper is intended to demystify the renewable generation, and turnsmore » the negative perception into positive revelation of the superiority of PV generation to the power quality improvement in a microgrid system. The main objective of this work is to develop a control method for the PV inverter so that the power quality at the PCC will be improved under various disturbances. The method is to control the reactive current based on utilizing the grid current to counteract the negative impact of the disturbances. The proposed control method is verified in PSIM platform. Promising results have been obtained.« less

  8. 77 FR 34093 - License Renewal for Calvert Cliffs Nuclear Power Plant, LLC's

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-08

    ... quality; water quality and use; geology and soils; ecology; noise; historical and cultural; scenic and... significantly affect the quality of the human environment. Therefore, preparation of an environmental impact...

  9. High-slope-efficiency 2.06 μm Ho: YLF laser in-band pumped by a fiber-coupled broadband diode.

    PubMed

    Ji, Encai; Liu, Qiang; Nie, Mingming; Cao, Xuezhe; Fu, Xing; Gong, Mali

    2016-03-15

    We first demonstrate the laser performance of a compact 2.06 μm Ho: YLF laser resonantly pumped by a broadband fiber-coupled diode. In continuous-wave (CW) operation, maximum output power of 1.63 W, corresponding to a slope efficiency of 89.2%, was obtained with a near diffraction-limited beam quality. In actively Q-switched operation, maximum pulse energy of 1.1 mJ was achieved at the repetition frequency of 100 Hz. The minimum pulse duration was 43 ns. The performance in both the CW and Q-switched regimes indicates that the current fiber-coupled diode in-band pumped Ho: YLF laser has great potential in certain conditions that require several watts of output power or several millijoules of short pulse energy.

  10. Radiation Hardened, Modulator ASIC for High Data Rate Communications

    NASA Technical Reports Server (NTRS)

    McCallister, Ron; Putnam, Robert; Andro, Monty; Fujikawa, Gene

    2000-01-01

    Satellite-based telecommunication services are challenged by the need to generate down-link power levels adequate to support high quality (BER approx. equals 10(exp 12)) links required for modem broadband data services. Bandwidth-efficient Nyquist signaling, using low values of excess bandwidth (alpha), can exhibit large peak-to-average-power ratio (PAPR) values. High PAPR values necessitate high-power amplifier (HPA) backoff greater than the PAPR, resulting in unacceptably low HPA efficiency. Given the high cost of on-board prime power, this inefficiency represents both an economical burden, and a constraint on the rates and quality of data services supportable from satellite platforms. Constant-envelope signals offer improved power-efficiency, but only by imposing a severe bandwidth-efficiency penalty. This paper describes a radiation- hardened modulator which can improve satellite-based broadband data services by combining the bandwidth-efficiency of low-alpha Nyquist signals with high power-efficiency (negligible HPA backoff).

  11. Photonic crystal fiber technology for compact fiber-delivered high-power ultrafast fiber lasers

    NASA Astrophysics Data System (ADS)

    Triches, Marco; Michieletto, Mattia; Johansen, Mette M.; Jakobsen, Christian; Olesen, Anders S.; Papior, Sidsel R.; Kristensen, Torben; Bondue, Magalie; Weirich, Johannes; Alkeskjold, Thomas T.

    2018-02-01

    Photonic crystal fiber (PCF) technology has radically impacted the scientific and industrial ultrafast laser market. Reducing platform dimensions are important to decrease cost and footprint while maintaining high optical efficiency. We present our recent work on short 85 μm core ROD-type fiber amplifiers that maintain single-mode performance and excellent beam quality. Robust long-term performance at 100 W average power and 250 kW peak power in 20 ps pulses at 1030 nm wavelength is presented, exceeding 500 h with stable performance in terms of both polarization and power. In addition, we present our recent results on hollow-core ultrafast fiber delivery maintaining high beam quality and polarization purity.

  12. Note: Application of CR-39 plastic nuclear track detectors for quality assurance of mixed oxide fuel pellets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kodaira, S., E-mail: koda@nirs.go.jp; Kurano, M.; Hosogane, T.

    A CR-39 plastic nuclear track detector was used for quality assurance of mixed oxide fuel pellets for next-generation nuclear power plants. Plutonium (Pu) spot sizes and concentrations in the pellets are significant parameters for safe use in the plants. We developed an automatic Pu detection system based on dense α-radiation tracks in the CR-39 detectors. This system would greatly improve image processing time and measurement accuracy, and will be a powerful tool for rapid pellet quality assurance screening.

  13. Theoretical Investigation For The Effect of Fuel Quality on Gas Turbine Power Plants

    NASA Astrophysics Data System (ADS)

    AbdulRazzak khudair, Omar; Alwan Abass, Khetam; Saadi Abed, Noor; Hussain Ali, Khalid; AbdulAziz, Saad; Chlaib Shaboot, Ali

    2018-05-01

    Gas turbine engine power generation is declined dramatically because of the reduction in thermodynamic parameters as a work of turbine, compressor ratio, compressor work, and air mass flow rate and fuel consumption. There are two main objectives of this work, the first is related with the effect of fuel kinds and their quality on the operation of fuel flow divider and its performance specifically gear pump displacement and fuel flow rate to the combustion chambers of gas power plant. AL-DORA gas turbine power plant 35MW was chosen to predict these effects on its performance MATLAB Software program is used to perform thermodynamic calculations. Fuel distribution stage before the process of combustion and as a result of the kind and its quality, chemical reaction will occur between the fuel and the parts of the gear system of each pump of the flow divider, which causes the erosion of the internal pump wall and the teeth of the gear system, thus hampering the pump operation in terms of fuel discharge. The discharge of fuel form the eight external gates of flow divider is decreased and varied when going to the combustion chambers, so that, flow divider does not give reliable mass flow rate due to absence of accurate pressure in each of eight exit pipes. The second objective deals with the stage of fuel combustion process inside the combustion chamber. A comparative study based upon performance parameters, such as specific fuel consumption for gas and gasoil and power generation. Fuel poor quality causes incomplete combustion and increased its consumption, so that combustion products are interacted with the surface of the turbine blades, causing the erosion and create surface roughness of the blade and disruption of gas flow. As a result of this situation, turbulence flow of these gases will increase causing the separation of gas boundary layers over the suction surface of the blade. Therefore the amount of extracted gas will decrease causing retreat work done by turbine, as a result decline of power and gas turbine power plant efficiency causing the drop in the level of electric generation. The fuel quality is found to be a strong function of specific fuel consumption and its effects on the power generation and the efficiency of the gas turbine power plants and hence, the cycle performance shifts towards favorable conditions.

  14. Predicting the Occurrence of Haze Events in Southeast Asia using Machine Learning Algorithms

    NASA Astrophysics Data System (ADS)

    Lee, H. H.; Chulakadabba, A.; Tonks, A.; Yang, Z.; Wang, C.

    2017-12-01

    Severe local- and regional-scale air pollution episodes typically originate from 1) high emissions of air pollutants, 2) poor dispersion conditions, and 3) trans-boundary pollutant transport. Biomass burning activities have become more frequent in Southeast Asia, especially in Sumatra, Borneo, and the mainland Southeast. Trans-boundary transport of biomass burning aerosols often lead to air quality problems in the region. Furthermore, particulate pollutants from human activities besides biomass burning also play an important role in the air quality of Southeast Asia. Singapore, for example, has a dynamic industrial sector including chemical, electric and metallurgic industries, and is the region's major petroleum-refining center. In addition, natural gas and oil power plants, waste incinerators, active port traffic, and a major regional airport further complicate Singapore's air quality issues. In this study, we compare five Machine Learning algorithms: k-Nearest Neighbors, Linear Support Vector Machine, Decision Tree, Random Forest and Artificial Neural Network, to identify haze patterns and determine variable importance. The algorithms were trained using local atmospheric data (i.e. months, atmospheric conditions, wind direction and relative humidity) from three observation stations in Singapore (Changi, Seletar and Paya Labar). We find that the algorithms reveal the associations in data within and between the stations, and provide in-depth interpretation of the haze sources. The algorithms also allow us to predict the probability of haze episodes in Singapore and to determine the correlation between this probability and atmospheric conditions.

  15. Extent and quality of systematic review evidence related to minimum intervention in dentistry: essential oils, powered toothbrushes, triclosan, xylitol.

    PubMed

    Mickenautsch, Steffen; Yengopal, Veerasamy

    2011-08-01

    To investigate extent and quality of current systematic review evidence regarding: powered toothbrushes, triclosan toothpaste, essential oil mouthwashes, xylitol chewing gum. Five databases were searched for systematic reviews until 13 November 2010. relevant to topic, systematic review according to title and/or abstract, published in English. Article exclusion criteria were based on QUOROM recommendations for the reporting of systematic review methods. Systematic review quality was judged using the AMSTAR tool. All trials included by reviews were assessed for selection bias. 119 articles were found, of which 11 systematic reviews were included. Of these, six were excluded and five accepted: one for triclosan toothpaste; one for xylitol chewing gum; two for powered toothbrushes; one for essential oil mouthwashes. AMSTAR scores: triclosan toothpaste 7; powered toothbrushes 9 and 11; xylitol chewing gum 9; essential oil mouthwashes 8. In total, 75 (out of 76) reviewed trials were identified. In-depth assessment showed a high risk of selection bias for all trials. The extent of available systematic review evidence is low. Although the few identified systematic reviews could be rated as of medium and high quality, the validity of their conclusions needs to be treated with caution, owing to high risk of selection bias in the reviewed trials. High quality randomised control trials are needed in order to provide convincing evidence regarding true clinical efficacy. © 2011 FDI World Dental Federation.

  16. Design and realization of an active SAR calibrator for TerraSAR-X

    NASA Astrophysics Data System (ADS)

    Dummer, Georg; Lenz, Rainer; Lutz, Benjamin; Kühl, Markus; Müller-Glaser, Klaus D.; Wiesbeck, Werner

    2005-10-01

    TerraSAR-X is a new earth observing satellite which will be launched in spring 2006. It carries a high resolution X-band SAR sensor. For high image data quality, accurate ground calibration targets are necessary. This paper describes a novel system concept for an active and highly integrated, digitally controlled SAR system calibrator. A total of 16 active transponder and receiver systems and 17 receiver only systems will be fabricated for a calibration campaign. The calibration units serve for absolute radiometric calibration of the SAR image data. Additionally, they are equipped with an extra receiver path for two dimensional satellite antenna pattern recognition. The calibrator is controlled by a dedicated digital Electronic Control Unit (ECU). The different voltages needed by the calibrator and the ECU are provided by the third main unit called Power Management Unit (PMU).

  17. Power-Quality Improvement in PFC Bridgeless SEPIC-Fed BLDC Motor Drive

    NASA Astrophysics Data System (ADS)

    Singh, Bhim; Bist, Vashist

    2013-06-01

    This article presents a design of a power factor correction (PFC)-based brushless DC (BLDC) motor drive. The speed control of BLDC motor is achieved by controlling the DC link voltage of the voltage source inverter (VSI) feeding BLDC motor using a single voltage sensor. A front-end bridgeless single-ended primary inductance converter (SEPIC) is used for DC link voltage control and PFC operation. A bridgeless SEPIC is designed to operate in discontinuous inductor current mode (DICM) thus utilizing a simple control scheme of voltage follower. An electronic commutation of BLDC motor is used for VSI to operate in a low-frequency operation for reduced switching losses in the VSI. Moreover, a bridgeless topology offers less conduction losses due to absence of diode bridge rectifier for further increasing the efficiency. The proposed BLDC motor drive is designed to operate over a wide range of speed control with an improved power-quality at the AC mains under the recommended international power-quality standards such as IEC 61000-3-2.

  18. The Role of Soil Organic Matter, Nutrients, and Microbial Community Structure on the Performance of Microbial Fuel Cells

    NASA Astrophysics Data System (ADS)

    Rooney-Varga, J. N.; Dunaj, S. J.; Vallino, J. J.; Hines, M. E.; Gay, M.; Kobyljanec, C.

    2011-12-01

    Microbial fuel cells (MFCs) offer the potential for generating electricity, mitigating greenhouse gas emissions, and bioremediating pollutants through utilization of a plentiful, natural, and renewable resource: soil organic carbon. In the current study, we analyzed microbial community structure, MFC performance, and soil characteristics in different microhabitats (bulk soil, anode, and cathode) within MFCs constructed from agricultural or forest soils in order to determine how soil type and microbial dynamics influence MFC performance. MFCs were constructed with soils from agricultural and hardwood forest sites at Harvard Forest (Petersham, MA). The bulk soil characteristics were analyzed, including polyphenols, short chain fatty acids, total organic C and N, abiotic macronutrients, N and P mineralization rates, CO2 respiration rates, and MFC power output. Microbial community structure of the anodes, cathodes, and bulk soils was determined with molecular fingerprinting methods, which included terminal restriction length polymorphism (T-RFLP) analysis and 16S rRNA gene sequencing analysis. Our results indicated that MFCs constructed from agricultural soil had power output about 17 times that of forest soil-based MFCs and respiration rates about 10 times higher than forest soil MFCs. Agricultural soil MFCs had lower C:N ratios, polyphenol content, and acetate concentrations than forest soil MFCs, suggesting that active agricultural MFC microbial communities were supported by higher quality organic carbon. Microbial community profile data indicate that the microbial communities at the anode of the high power MFCs were less diverse than in low power MFCs and were dominated by Deltaproteobacteria, Geobacter, and, to a lesser extent, Clostridia, while low-power MFC anode communities were dominated by Clostridia. These data suggest that the presence of organic carbon substrate (acetate) was not the major limiting factor in selecting for highly electrogenic microbial communities, while the quality of available organic matter may have played a significant role in supporting high performing microbial communities.

  19. Trading Quality across Borders: Colonial Discourse and International Quality Assurance Policies in Higher Education

    ERIC Educational Resources Information Center

    Blanco Ramírez, Gerardo

    2014-01-01

    Accountability and quality assurance have become central discourses in higher education policy throughout the world. However, accountability and quality assurance involve power and control. Practices and ideas about quality developed in the Global North are spreading rapidly across the Global South, leading to increased uniformity in the…

  20. Power quality improvement of a stand-alone power system subjected to various disturbances

    NASA Astrophysics Data System (ADS)

    Lone, Shameem Ahmad; Mufti, Mairaj Ud-Din

    In wind-diesel stand-alone power systems, the disturbances like random nature of wind power, turbulent wind, sudden changes in load demand and the wind park disconnection effect continuously the system voltage and frequency. The satisfactory operation of such a system is not an easy task and the control design has to take in to account all these subtleties. For maintaining the power quality, generally, a short-term energy storage device is used. In this paper, the performance of a wind-diesel system associated with a superconducting magnetic energy storage (SMES) system is studied. The effect of installing SMES at wind park bus/load bus, on the system performance is investigated. To control the exchange of real and reactive powers between the SMES unit and the wind-diesel system, a control strategy based on fuzzy logic is proposed. The dynamic models of the hybrid power system for most common scenarios are developed and the results presented.

  1. Lighting Systems For High Speed Photography Applying Special Metal Halide Discharge Lamps

    NASA Astrophysics Data System (ADS)

    Gillum, Keith M.; Steuernagel, K. H.

    1983-03-01

    High speed photography requires, in addition to a good color quality of the light source, a very high level of illumination. Conventional lighting systems utilizing incandescent lamps or other metal halide lamp types has inherent problems of inefficient light output or poor color quality. Heat generated by incandescent lamps and the power these sources require drive up operating and installation costs. A most economical and practical solution was devised by using the metal halide discharge lamp developed by OSRAM, GmbH of Munich, West Germany. This lamp trade marked the HMITM Metallogen was primarily developed for the needs of the television and motion picture film industry. Due to their high efficiency and other consistent operating qualities these lamps also fulfill the needs of high speed photography, e.g. in crash test facilities, when special engineering activities are carried out. The OSRAM HMITM lamp is an AC discharge metal halide lamp with rare earth additives to increase both the efficiency and light output qualities. Since the lamp is an AC source, a special method had to be developed to overcome the strobing effect, which is normal for AC lamps given their modulated light output, when used with high speed cameras, (e.g. with >1000 fps). This method is based on an increased frequency for the lamp supply voltage coupled with a mix of the light output achieved using a multiphase mains power supply. First developed in 1977, this system using the OSRAM HMITM lamps was installed in a crash test facility of a major automotive manufacturer in West Germany. The design resulted in the best lighting and performance ever experienced. Since that time several other motor companies have made use of this breakthrough. Industrial and scientific users are now considering additional applications use of this advanced high speed lighting system.

  2. Annual report to Congress, FY 1992

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1993-07-01

    The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for disposing of the Nation`s spent nuclear fuel from civilian nuclear power reactors and high-level radioactive waste from its defense activities in a cost-effective manner that protects the health and safety of the public and workers and the quality of the environment. To accomplish this mission OCRWM is developing a waste management system consisting of a geologic repository, a facility for monitored retrievable storage, and a system for transporting the waste. This is the ninth annual report submitted by the OCRWM to Congress. The OCRWM submits this report to informmore » Congress of its activities and expenditures during fiscal year 1992 (October 1, 1991 through September 30, 1992).« less

  3. Software engineering for ESO's VLT project

    NASA Astrophysics Data System (ADS)

    Filippi, G.

    1994-12-01

    This paper reports on the experience at the European Southern Observatory on the application of software engineering techniques to a 200 man-year control software project for the Very Large Telescope (VLT). This shall provide astronomers, before the end of the century, with one of the most powerful telescopes in the world. From the definition of the general model, described in the software management plan, specific activities have been and will be defined: standards for documents and for code development, design approach using a CASE tool, the process of reviewing both documentation and code, quality assurance, test strategy, etc. The initial choices, the current implementation and the future planned activities are presented and, where feedback is already available, pros and cons are discussed.

  4. False alarm reduction in BSN-based cardiac monitoring using signal quality and activity type information.

    PubMed

    Tanantong, Tanatorn; Nantajeewarawat, Ekawit; Thiemjarus, Surapa

    2015-02-09

    False alarms in cardiac monitoring affect the quality of medical care, impacting on both patients and healthcare providers. In continuous cardiac monitoring using wireless Body Sensor Networks (BSNs), the quality of ECG signals can be deteriorated owing to several factors, e.g., noises, low battery power, and network transmission problems, often resulting in high false alarm rates. In addition, body movements occurring from activities of daily living (ADLs) can also create false alarms. This paper presents a two-phase framework for false arrhythmia alarm reduction in continuous cardiac monitoring, using signals from an ECG sensor and a 3D accelerometer. In the first phase, classification models constructed using machine learning algorithms are used for labeling input signals. ECG signals are labeled with heartbeat types and signal quality levels, while 3D acceleration signals are labeled with ADL types. In the second phase, a rule-based expert system is used for combining classification results in order to determine whether arrhythmia alarms should be accepted or suppressed. The proposed framework was validated on datasets acquired using BSNs and the MIT-BIH arrhythmia database. For the BSN dataset, acceleration and ECG signals were collected from 10 young and 10 elderly subjects while they were performing ADLs. The framework reduced the false alarm rate from 9.58% to 1.43% in our experimental study, showing that it can potentially assist physicians in diagnosing a vast amount of data acquired from wireless sensors and enhance the performance of continuous cardiac monitoring.

  5. Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Kalaeloa Oahu, Hawaii (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2010-03-16

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  6. Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Los Angeles, California (Data)

    DOE Data Explorer

    Stoffel, T.; Andreas, A.

    2010-04-26

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  7. Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Cedar City, Utah (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2010-07-13

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  8. Solar Resource and Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Escalante Tri-State - Prewitt, New Mexico (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2012-11-03

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  9. Solar Resource & Meteorological Assessment Project (SOLRMAP): Sun Spot Two; Swink, Colorado (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2010-11-10

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  10. Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Milford, Utah (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2010-07-14

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  11. Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); La Ola Lanai, Hawaii (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2009-07-22

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  12. Solar Resource & Meteorological Assessment Project (SOLRMAP): Observed Atmospheric and Solar Information System (OASIS); Tucson, Arizona (Data)

    DOE Data Explorer

    Wilcox, S.; Andreas, A.

    2010-11-03

    The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  13. High beam quality and high energy short-pulse laser with MOPA

    NASA Astrophysics Data System (ADS)

    Jin, Quanwei; Pang, Yu; Jiang, JianFeng; Tan, Liang; Cui, Lingling; Wei, Bin; Sun, Yinhong; Tang, Chun

    2018-03-01

    A high energy, high beam quality short-pulse diode-pumped Nd:YAG master oscillator power-amplifier (MOPA) laser with two amplifier stages is demonstrated. The two-rod birefringence compensation was used as beam quality controlling methods, which presents a short-pulse energy of 40 mJ with a beam quality value of M2 = 1.2 at a repetition rate of 400Hz. The MOPA system delivers a short-pulse energy of 712.5 mJ with a pulse width of 12.4 ns.The method of spherical aberration compensation is improved the beam quality, a M2 factor of 2.3 and an optical-to-optical efficiency of 27.7% is obtained at the maximum laser out power.The laser obtained 1.4J out energy with polarization integration.

  14. Agent-based power sharing scheme for active hybrid power sources

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenhua

    The active hybridization technique provides an effective approach to combining the best properties of a heterogeneous set of power sources to achieve higher energy density, power density and fuel efficiency. Active hybrid power sources can be used to power hybrid electric vehicles with selected combinations of internal combustion engines, fuel cells, batteries, and/or supercapacitors. They can be deployed in all-electric ships to build a distributed electric power system. They can also be used in a bulk power system to construct an autonomous distributed energy system. An important aspect in designing an active hybrid power source is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. This paper presents an agent-based power sharing scheme for active hybrid power sources. To demonstrate the effectiveness of the proposed agent-based power sharing scheme, simulation studies are performed for a hybrid power source that can be used in a solar car as the main propulsion power module. Simulation results clearly indicate that the agent-based control framework is effective to coordinate the various energy sources and manage the power/voltage profiles.

  15. Fully vectorial laser resonator modeling of continuous-wave solid-state lasers including rate equations, thermal lensing and stress-induced birefringence.

    PubMed

    Asoubar, Daniel; Wyrowski, Frank

    2015-07-27

    The computer-aided design of high quality mono-mode, continuous-wave solid-state lasers requires fast, flexible and accurate simulation algorithms. Therefore in this work a model for the calculation of the transversal dominant mode structure is introduced. It is based on the generalization of the scalar Fox and Li algorithm to a fully-vectorial light representation. To provide a flexible modeling concept of different resonator geometries containing various optical elements, rigorous and approximative solutions of Maxwell's equations are combined in different subdomains of the resonator. This approach allows the simulation of plenty of different passive intracavity components as well as active media. For the numerically efficient simulation of nonlinear gain, thermal lensing and stress-induced birefringence effects in solid-state active crystals a semi-analytical vectorial beam propagation method is discussed in detail. As a numerical example the beam quality and output power of a flash-lamp-pumped Nd:YAG laser are improved. To that end we compensate the influence of stress-induced birefringence and thermal lensing by an aspherical mirror and a 90° quartz polarization rotator.

  16. Crucial aspects promoting meaning and purpose in life: perceptions of nursing home residents.

    PubMed

    Drageset, Jorunn; Haugan, Gørill; Tranvåg, Oscar

    2017-10-30

    Meaning and purpose in life are fundamental to human beings. In changing times, with an aging population and increased life expectancy, the need for health care services and long-term care is likely to grow. More deeply understanding how older long-term care residents perceive meaning and purpose in life is critical for improving the quality of care and the residents' quality of life. The purpose of this study was to explore crucial aspects promoting nursing home residents' experience of meaning and purpose in everyday life. An exploratory hermeneutical design with qualitative interviews for collecting data. Four key experiences were found to promote meaning and purpose in life: 1) physical and mental well-being, 2) belonging and recognition, 3) personally treasured activities and 4) spiritual closeness and connectedness. In supporting meaning and purpose in life of nursing home residents, the residents' everyday well-being should be a central focus of care and facilitate personally treasured activities. Focused attention should also be given to the meaning-making power of experiencing belonging, recognition and spiritual connectedness.

  17. Fabrication and characterization of Tm3+-Ho3+ co-doped tellurite glass microsphere lasers operating at ∼2.1 μm

    NASA Astrophysics Data System (ADS)

    Yang, Zhengsheng; Wu, Yuehao; Yang, Kun; Xu, Peipeng; Zhang, Wei; Dai, Shixun; Xu, Tiefeng

    2017-10-01

    We used a Tm3+-Ho3+ co-doped tellurite glass as the laser medium to build active microsphere laser resonators. A droplet method is implemented and hundreds of high quality microspheres can be fabricated simultaneously. Typical Quality factors (Q-factors) of microspheres fabricated in this work reach 106. Silica fiber tapers are used as the coupling mechanism and a commercial 808 nm laser diode is used as the pump source. Laser lines at ∼2.1 μm can be observed in the emission spectrum of these active microsphere resonators. Pump thresholds for generating single mode laser lines in a 59.52 μm diameter microsphere is measured to be 0.887 mW and as the pump power is increased to 1.413 mW, multi-mode laser lines can be generated. We also demonstrate microsphere lasers fabricated in this work can be thermally tuned with a temperature sensitivity of 32 pm/°C, implying these microspheres can be used as highly compact temperature sensors in various mid-infrared applications.

  18. 2.1 μm high-power laser diode beam combining(Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Berrou, Antoine P. C.; Elder, Ian F.; Lamb, Robert A.; Esser, M. J. Daniel

    2016-10-01

    Laser power and brightness scaling, in "eye safe" atmospheric transmission windows, is driving laser system research and development. High power lasers with good beam quality, at wavelength around 2.1 µm, are necessary for optical countermeasure applications. For such applications, focusing on efficiency and compactness of the system is mandatory. In order to cope with these requirements, one must consider the use of laser diodes which emit directly in the desired spectral region. The challenge for these diodes is to maintain a good beam quality factor as the output power increases. 2 µm diodes with excellent beam quality in both axes are available with output powers of 100 mW. Therefore, in order to reach multi-watt of average output power, broad-area single emitters and beam combining becomes relevant. Different solutions have been implemented in the 1.9 to 2 µm wavelength range, one of which is to stack multiple emitter bars reaching more than one hundred watt, while another is a fibre coupled diode module. The beam propagation factor of these systems is too high for long atmospheric propagation applications. Here we describe preliminary results on non-coherent beam combining of 2.1 µm high power Fabry-Perot GaSb laser diodes supplied by Brolis Semiconductors Ltd. First we evaluated single mode diodes (143 mW) with good beam quality (M2 < 1.5 for slow axis and < 1.1 for fast axis). Then we characterized broad-area single emitter diodes (808 mW) with an electrical-to-optical efficiency of 19 %. The emitter width was 90 µm with a cavity length of 1.5 mm. In our experiments we found that the slow axis multimode output beam consisted of two symmetric lobes with a total full width at half maximum (FWHM) divergence angle of 25 degrees, corresponding to a calculated beam quality factor of M2 = 25. The fast axis divergence was specified to be 44 degrees, with an expected beam quality factor close to the diffraction limit, which informed our selection of collimation lenses used in the experiment. We evaluated two broadband (1.8 - 3 µm) AR coated Geltech aspheric lenses with focal lengths of 1.87 mm and 4 mm, with numerical apertures of 0.85 and 0.56, respectively, as an initial collimation lens, followed by an additional cylindrical lens of focal length 100 mm for fully collimating the slow axis. Using D-shaped gold-coated mirrors, multiple single emitter beams are stacked in the fast axis direction with the objective that the combined beam has a beam propagation factor in the stacking direction close to the beam propagation factor of the slow axis of a single emitter, e.g. M2 of 20 to 25 in both axes. We further found that the output beam of a single emitter is highly linearly polarized along the slow axis, making it feasible to implement polarization beam combining techniques to increase the beam power by a factor two while maintaining the same beam quality. Along with full beam characterization, a power scaling strategy towards a multi-watt output power beam combining laser system will be presented.

  19. Cooking Characteristics and Antioxidant Activity of Rice-Barley Mix at Different Cooking Method and Mixing Ratio.

    PubMed

    Woo, Koan Sik; Kim, Hyun-Joo; Lee, Ji Hae; Ko, Jee Yeon; Lee, Byong Won; Lee, Byoung Kyu

    2018-03-01

    This study aimed to compare the phenolic compounds and antioxidant activity of barley at different proportion (0, 5, 10, 15, and 20%), and using different cooking methods. The grains used in this experiment are barley ( Hordeum vulgare L. cv. Huinchalssal) and Samkwang rice. The rice-barley mixture was cooked using general and high pressure cooking methods with and without fermented alcohol. The quality characteristics such as water binding capacity, pasting characteristic, water solubility, and swelling power of different proportions of barley were evaluated. The antioxidant characteristics evaluated are total polyphenol, flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2-azinobis(3-ethylbenothiazoline-6-sulphonic acid) (ABTS) diammonium salt radical scavenging activities. Results showed that peak [195.0~184.0 rapid visco units (RVU)], trough (130.0~116.2 RVU), final (252.0~221.8 RVU), and setback viscosity (57.0~37.5 RVU) decreased correspondingly with the increase in the amount of barley. Water binding capacity (187.31~136.01%) and swelling power (162.37~127.58%) decreased as amounts of barley increases, however the water solubility (5.35~6.89%) increased. Moreover, the total polyphenol and flavonoid, and the DPPH and ABTS radical scavenging activities contents increased as the amounts of barley in the mixture increases. This study generally aims to provide useful information for the manufacturing of processed products.

  20. Social power and approach-related neural activity

    PubMed Central

    Smolders, Ruud; Cremer, David De

    2012-01-01

    It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high or low social power. Results show that high social power is indeed associated with greater left-frontal brain activity compared to low social power, providing the first neural evidence for the theory that high power is associated with approach-related motivation. We propose a framework accounting for differences in both approach motivation and goal-directed behaviour associated with different levels of power. PMID:19304842

  1. Social power and approach-related neural activity.

    PubMed

    Boksem, Maarten A S; Smolders, Ruud; De Cremer, David

    2012-06-01

    It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high or low social power. Results show that high social power is indeed associated with greater left-frontal brain activity compared to low social power, providing the first neural evidence for the theory that high power is associated with approach-related motivation. We propose a framework accounting for differences in both approach motivation and goal-directed behaviour associated with different levels of power.

  2. 18 CFR 12.40 - Quality control programs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Quality control... PROJECT WORKS Other Responsibilities of Applicant or Licensee § 12.40 Quality control programs. (a... meeting any requirements or standards set by the Regional Engineer. If a quality control program is...

  3. 18 CFR 12.40 - Quality control programs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Quality control... PROJECT WORKS Other Responsibilities of Applicant or Licensee § 12.40 Quality control programs. (a... meeting any requirements or standards set by the Regional Engineer. If a quality control program is...

  4. 12 CFR 721.2 - What is an incidental powers activity?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false What is an incidental powers activity? 721.2 Section 721.2 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS INCIDENTAL POWERS § 721.2 What is an incidental powers activity? An incidental powers activity is one that is...

  5. Coherent combining of high brightness tapered lasers in master oscillator power amplifier configuration

    NASA Astrophysics Data System (ADS)

    Albrodt, P.; Hanna, M.; Moron, F.; Decker, J.; Winterfeldt, M.; Blume, G.; Erbert, G.; Crump, P.; Georges, P.; Lucas-Leclin, G.

    2018-02-01

    Improved diode laser beam combining techniques are in strong demand for applications in material processing. Coherent beam combining (CBC) is the only combining approach that has the potential to maintain or even improve all laser properties, and thus has high potential for future systems. As part of our ongoing studies into CBC of diode lasers, we present recent progress in the coherent superposition of high-power single-pass tapered laser amplifiers. The amplifiers are seeded by a DFB laser at λ = 976 nm, where the seed is injected into a laterally single-mode ridge-waveguide input section. The phase pistons on each beam are actively controlled by varying the current in the ridge section of each amplifier, using a sequential hill-climbing algorithm, resulting in a combined beam with power fluctuations of below 1%. The currents into the tapered sections of the amplifiers are separately controlled, and remain constant. In contrast to our previous studies, we favour a limited number of individual high-power amplifiers, in order to preserve a high extracted power per emitter in a simple, low-loss coupling arrangement. Specifically, a multi-arm interferometer architecture with only three devices is used, constructed using 6 mm-long tapered amplifiers, mounted junction up on C-mounts, to allow separate contact to single mode and amplifier sections. A maximum coherently combined power of 12.9 W is demonstrated in a nearly diffraction-limited beam, corresponding to a 65% combining efficiency, with power mainly limited by the intrinsic beam quality of the amplifiers. Further increased combined power is currently sought.

  6. Simulation and study of power quality issues in a fixed speed wind farm substation.

    PubMed

    Magesh, T; Chellamuthu, C

    2015-01-01

    Power quality issues associated with the fixed speed wind farm substation located at Coimbatore district are investigated as the wind generators are tripping frequently. The investigations are carried out using two power quality analyzers, Fluke 435 and Dranetz PX5.8, with one of them connected at group control breaker of the 110 kV feeder and the other at the selected 0.69 kV generator busbar during the period of maximum power generation. From the analysis of the recorded data it is found that sag, swell, and transients are the major events which are responsible for the tripping of the generators. In the present study, simulation models for wind, turbine, shaft, pitch mechanism, induction generator, and grid are developed using DIgSILENT. Using the turbine characteristics, a two-dimensional lookup table is designed to generate a reference pitch angle necessary to simulate the power curve of the passive stall controlled wind turbine. Various scenarios and their effects on the performance of the wind farm are studied and validated with the recorded data and waveforms. The simulation model will be useful for the designers for planning and development of the wind farm before implementation.

  7. Simulation and Study of Power Quality Issues in a Fixed Speed Wind Farm Substation

    PubMed Central

    Magesh, T.; Chellamuthu, C.

    2015-01-01

    Power quality issues associated with the fixed speed wind farm substation located at Coimbatore district are investigated as the wind generators are tripping frequently. The investigations are carried out using two power quality analyzers, Fluke 435 and Dranetz PX5.8, with one of them connected at group control breaker of the 110 kV feeder and the other at the selected 0.69 kV generator busbar during the period of maximum power generation. From the analysis of the recorded data it is found that sag, swell, and transients are the major events which are responsible for the tripping of the generators. In the present study, simulation models for wind, turbine, shaft, pitch mechanism, induction generator, and grid are developed using DIgSILENT. Using the turbine characteristics, a two-dimensional lookup table is designed to generate a reference pitch angle necessary to simulate the power curve of the passive stall controlled wind turbine. Various scenarios and their effects on the performance of the wind farm are studied and validated with the recorded data and waveforms. The simulation model will be useful for the designers for planning and development of the wind farm before implementation. PMID:25950016

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Davis, Lynn; Arquit Niederberger, Anne

    Abstract— Lighting systems have the ability to transform the economic and educational infrastructure of disadvantaged communities, and eradicating “light poverty” has become one of the primary goals of the International Year of Light 2015. Solid-state lighting (SSL) technology, based on light-emitting diode (LED) light sources, has emerged as the next generation of lighting technology, with a current global market penetration of roughly 5%. This paper will report on recent research on understanding SSL lighting system reliability (failure modes, environmental stressors, electrical power quality); discuss the implications of SSL technology reliability for providing lighting services; and suggest practical approaches to ensuremore » SSL reliability to benefit humanity. Among the key findings from this work is that LED sources can be extremely reliable, withstanding a broad range of environmental stresses without failure. Nonetheless, SSL lighting systems can have a negative impact on electrical power reliability, as well as on the affordability of lighting services, without attention to the quality of the accompanying power infrastructure. It is therefore critical to ensure that the performance of the power supply electronics used in lighting systems is matched to the quality of the power source, when evaluating energy efficient lighting choices.« less

  9. From Field Notes to Data Portal - A Scalable Data QA/QC Framework for Tower Networks: Progress and Preliminary Results

    NASA Astrophysics Data System (ADS)

    Sturtevant, C.; Hackley, S.; Lee, R.; Holling, G.; Bonarrigo, S.

    2017-12-01

    Quality assurance and control (QA/QC) is one of the most important yet challenging aspects of producing research-quality data. Data quality issues are multi-faceted, including sensor malfunctions, unmet theoretical assumptions, and measurement interference from humans or the natural environment. Tower networks such as Ameriflux, ICOS, and NEON continue to grow in size and sophistication, yet tools for robust, efficient, scalable QA/QC have lagged. Quality control remains a largely manual process heavily relying on visual inspection of data. In addition, notes of measurement interference are often recorded on paper without an explicit pathway to data flagging. As such, an increase in network size requires a near-proportional increase in personnel devoted to QA/QC, quickly stressing the human resources available. We present a scalable QA/QC framework in development for NEON that combines the efficiency and standardization of automated checks with the power and flexibility of human review. This framework includes fast-response monitoring of sensor health, a mobile application for electronically recording maintenance activities, traditional point-based automated quality flagging, and continuous monitoring of quality outcomes and longer-term holistic evaluations. This framework maintains the traceability of quality information along the entirety of the data generation pipeline, and explicitly links field reports of measurement interference to quality flagging. Preliminary results show that data quality can be effectively monitored and managed for a multitude of sites with a small group of QA/QC staff. Several components of this framework are open-source, including a R-Shiny application for efficiently monitoring, synthesizing, and investigating data quality issues.

  10. Power quality considerations for nuclear spectroscopy applications: Grounding

    NASA Astrophysics Data System (ADS)

    García-Hernández, J. M.; Ramírez-Jiménez, F. J.; Mondragón-Contreras, L.; López-Callejas, R.; Torres-Bribiesca, M. A.; Peña-Eguiluz, R.

    2013-11-01

    Traditionally the electrical installations are designed for supplying power and to assure the personnel safety. In nuclear analysis laboratories, additional issues about grounding also must be considered for proper operation of high resolution nuclear spectroscopy systems. This paper shows the traditional ways of grounding nuclear spectroscopy systems and through different scenarios, it shows the effects on the more sensitive parameter of these systems: the energy resolution, it also proposes the constant monitoring of a power quality parameter as a way to preserve or to improve the resolution of the systems, avoiding the influence of excessive extrinsic noise.

  11. An Approach Based on HPLC-Fingerprint and Chemometrics to Quality Consistency Evaluation of Matricaria chamomilla L. Commercial Samples

    PubMed Central

    Viapiana, Agnieszka; Struck-Lewicka, Wiktoria; Konieczynski, Pawel; Wesolowski, Marek; Kaliszan, Roman

    2016-01-01

    Chamomile has been used as an herbal medication since ancient times and is still popular because it contains various bioactive phytochemicals that could provide therapeutic effects. In this study, a simple and reliable HPLC method was developed to evaluate the quality consistency of nineteen chamomile samples through establishing a chromatographic fingerprint, quantification of phenolic compounds and determination of antioxidant activity. For fingerprint analysis, 12 peaks were selected as the common peaks to evaluate the similarities of commercial samples of chamomile obtained from different manufacturers. A similarity analysis was performed to assess the similarity/dissimilarity of chamomile samples where values varied from 0.868 to 0.990 what indicating that samples from different manufacturers were consistent. Additionally, simultaneous quantification of five phenolic acids (gallic, caffeic, syringic, p-coumaric, ferulic) and four flavonoids (rutin, myricetin, quercetin and keampferol) was performed to interpret the quality consistency. In quantitative analysis, the nine individual phenolic compounds showed good regression (r > 0.9975). Inter- and intra-day precisions for all analyzed compounds expressed as relative standard deviation (CV) ranged from 0.05% to 3.12%. Since flavonoids and other polyphenols are commonly recognized as natural antioxidants, the antioxidant activity of chamomile samples was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing/antioxidant power (FRAP) assay. Correlation analysis was used to assess the relationship between antioxidant activity and phenolic composition, and multivariate analysis (PCA and HCA) were applied to distinguish chamomile samples. Results shown in the study indicate high similarity of chamomile samples among them, widely spread in the market and commonly used by people as infusions or teas, as well as that there were no statistically significant differences among them, which in turn is a proof of high quality of commercially available samples of chamomile. The study indicated that the combination of chromatographic fingerprint and quantitative analysis can be readily utilized as a quality consistency method for chamomile and related medicinal preparations. Moreover, the applied strategy seems to be the most promising for the assessment of the investigated plant material. PMID:27818668

  12. Evaluation of Wound Healing Properties of Grape Seed, Sesame, and Fenugreek Oils

    PubMed Central

    Ksouda Moalla, Kamilia; Kammoun, Naziha Grati; Rebai, Tarek; Sahnoun, Zouheir

    2016-01-01

    Background. Medicinal plants have proved at all times to be a powerful remedy for health care. Accordingly, grape seed, sesame, and fenugreek extracted oils with pharmacological properties are investigated as wound treatments. This study assesses the potential of our oils for healing wounds induced on rats. Methods. Phytochemical analyses of oils have involved: quality value, polyphenol, chlorophylls, carotene, and fatty acids. Antibacterial activity was carried out. Antioxidant activity was evaluated: the scavenging effect on DPPH radicals, the reducing power, and β-carotene discoloration. Uniform wound excision was induced on rats dorsum randomly divided into five groups: groups treated with “CICAFLORA®” and tested oils and untreated one. The posthealing biopsies were histologically assessed. Results. Wound biopsies treated with oils showed the best tissue regeneration compared to control groups. Groups treated with our oils and “CICAFLORA” had higher wound contraction percentage. Polyunsaturated fatty acids in oils act as inflammatory mediators increasing neovascularization, extracellular remodeling, migration, and cell differentiation. Wound healing effect was attributed to antibacterial and antioxidant synergy. Conclusion. According to findings, oils showed better activity in wound healing compared to “CICAFLORA” due to a phytoconstituents synergy. However, clinical trials on humans are necessary to confirm efficacy on human pathology. PMID:27990170

  13. Environmental impact of geothermal power plants in Aydın, Turkey

    NASA Astrophysics Data System (ADS)

    Yilmaz, Ersel; Ali Kaptan, Mustafa

    2017-10-01

    Geothermal energy is classified as a clean and sustainable energy source, like all industrial activities, geothermal energy power plants (GEPP) technology has also some positive and negative effects on the environment. In this paper are presented by attent not only on environmental impacts of GEPP onto Büyük Menderes River and fresh water sources, which ere used for irrigation of agricultural fields from tousands of years in basin, but also on water quality contents like heavy metals and gases emition due to drilling and electricity producing technology of GEPP's. Aydın province is located in the southwestern part of the region and its city center has around 300000 population. The high geothermal potential of this region became from geographical location, which is held on active tectonic Alpine-Himalaya Orogen belt with active volcanoes and young faults. Since 1980's to 2016 there is about 70.97% (662.75 MW) of installed capacity by according to the Mineral Research and Exploration General Directorate, there are totally 290 well licensed (540 explore licenses and 76 business licenses), and 31 geothermal powerplants purposely installed. Topic is important because of number of GEPP increased rapidly after 2012 to now a days to 36 in whole basin.

  14. The characterization of secondary lithium-ion battery degradation when operating complex, ultra-high power pulsed loads

    NASA Astrophysics Data System (ADS)

    Wong, Derek N.

    The US Navy is actively developing all electric fleets, raising serious questions about what is required of onboard power supplies in order to properly power the ship's electrical systems. This is especially relevant when choosing a viable power source to drive high power propulsion and electric weapon systems in addition to the conventional loads deployed aboard these types of vessels. Especially when high pulsed power loads are supplied, the issue of maintaining power quality becomes important and increasingly complex. Conventionally, a vessel's electrical power is generated using gas turbine or diesel driven motor-generator sets that are very inefficient when they are used outside of their most efficient load condition. What this means is that if the generator is not being utilized continuously at its most efficient load capacity, the quality of the output power may also be effected and fall outside of the acceptable power quality limits imposed through military standards. As a solution to this potential problem, the Navy has proposed using electrochemical storage devices since they are able to buffer conventional generators when the load is operating below the generator's most efficient power level or able to efficiently augment a generator when the load is operating in excess of the generator's most efficient power rating. Specifically, the US Navy is interested in using commercial off-the-shelf (COTS) lithium-ion batteries within an intelligently controlled energy storage module that could act as either a prime power supply for on-board pulsed power systems or as a backup generator to other shipboard power systems. Due to the unique load profile of high-rate pulsed power systems, the implementation of lithium-ion batteries within these complex systems requires them to be operated at very high rates and the effects these things have on cell degradation has been an area of focus. There is very little published research into the effects that high power transient or pulsed loading has on the degradation mechanisms of secondary lithium-ion cells. Prior to performing this work, it was unclear if the implementation of lithium-ion batteries in highly transient load conditions at high rate would accelerate cell degradation mechanisms that have been previously considered as minor issues. This work has focused on answering these previously unanswered questions. In early experiments performed here, COTS lithium-iron-phosphate (LFP) cells were studied under high-rate, transient load conditions and it was found that their capacity fade deviated from the traditional linear behavior and exponentially declined until no charge could be accepted when recharge was attempted at high rate. These findings indicated that subjecting LFP chemistries to transient, high rate charge/discharge profiles induced rapid changes in the electrode/electrolyte interface that rendered the cells useless when high rate recharge was required. These findings suggested there was more phenomena to learn about how these cells degraded under high rate pulsed conditions before they are fielded in Naval applications. Therefore, the research presented here has been focused on understanding the degradation mechanisms that are unique to LFP cells when they are cycled under pulsed load profiles at high charge and discharge rates. In particular, the work has been focused on identifying major degradation reactions that occur by studying the surface chemistry of cycled electrode materials. Efforts have been performed to map the impedance evolution of both cathode and anode half cells, respectively, using a novel three electrode technique that was developed for this research. Using this technique, the progression of degradation has been mapped using analysis of differential capacitance spectrums. In both the three electrode EIS mapping and differential capacitance analysis that has been performed, electrical component models have been developed. The results presented will show that there are unique degradation mechanisms induced through high rate pulsed loading conditions that are not normally seen in low rate continuous cycling of LFP cells.

  15. Heart rate variability changes in business process outsourcing employees working in shifts.

    PubMed

    Kunikullaya, Kirthana U; Kirthi, Suresh K; Venkatesh, D; Goturu, Jaisri

    2010-10-31

    Irregular and poor quality sleep is common in business process outsourcing (BPO) employees due to continuous shift working. The influence of this on the cardiac autonomic activity was investigated by the spectral analysis of heart rate variability (HRV). 36 night shift BPO employees (working from 22:00 to 06:00h) and 36 age and sex matched day shift BPO employees (working from 08:00 to 16:00h) were recruited for the study. Five minute electrocardiogram (ECG) was recorded in all the subjects. Heart rate variability was analyzed by fast Fourier transformation using RMS Vagus HRV software. The results were analyzed using Mann Whitney U test, Student t-test, Wilcoxon signed rank test and were expressed as mean ± SD. Sleepiness was significantly higher among night shift workers as measured by Epworth Sleepiness Scale (p<0.001). Night shift BPO employees were found to have a trend towards lower values of vagal parameters - HF power (ms(2)), and higher values of sympathovagal parameters like LF Power (ms(2)) and the LF/HF power (%) suggesting decreased vagal activity and sympathetic over activity, when compared to day shift employees. However, HRV parameters did not vary significantly between the day shift employees and night shift workers baseline values, and also within the night shift group. Night shift working increased the heart rate and shifted the sympathovagal balance towards sympathetic dominance and decreased vagal parameters of HRV. This is an indicator of unfavorable change in the myocardial system, and thus shows increased risk of cardiovascular disease among the night shift employees.

  16. Multi-Fresnel lenses pumping approach for improving high-power Nd:YAG solar laser beam quality.

    PubMed

    Liang, Dawei; Almeida, Joana

    2013-07-20

    To significantly improve the present-day high-power solar laser beam quality, a three-stage multi-Fresnel lenses approach is proposed for side-pumping either a Nd:YAG single-crystal or a core-doped Sm(3+)Nd:YAG ceramic rod. Optimum pumping and laser beam parameters are found through ZEMAX and LASCAD numerical analysis. The proposed scheme offers a uniform absorption profile along the rod. 167 W laser power can be achieved, corresponding to 29.3 W/m(2) collection efficiency. High brightness figure of merit of 8.34 W is expected for the core-doped rod within a convex-concave resonator, which is 1300 times higher than that of the most-recent high-power solar laser.

  17. High Power Laser Welding. [of stainless steel and titanium alloy structures

    NASA Technical Reports Server (NTRS)

    Banas, C. M.

    1972-01-01

    A review of recent developments in high power, carbon dixoide laser welding is presented. Deep penetration welding in stainless steel to 0.5-in. thick, high speed welding in thin gage rimmed steel and gas shielded welding in Ti-6Al-4V alloy are described. The effects of laser power, power density, focusing optics, gas-shielding techniques, material properties and weld speed on weld quality and penetration are discussed. It is shown that laser welding performance in thin materials is comparable to that of electron beams. It is further shown that high quality welds, as evidenced by NDT, mechanical and metal-lographic tests, can be achieved. The potential of the laser for industrial welding applications is indicated.

  18. High pumping-power fiber combiner for double-cladding fiber lasers and amplifiers

    NASA Astrophysics Data System (ADS)

    Zheng, Jinkun; Zhao, Wei; Zhao, Baoyin; Li, Zhe; Chang, Chang; Li, Gang; Gao, Qi; Ju, Pei; Gao, Wei; She, Shengfei; Wu, Peng; Hou, Chaoqi; Li, Weinan

    2018-03-01

    A high pumping-power fiber combiner for backward pumping configurations is fabricated and demonstrated by manufacturing process refinement. The pump power handling capability of every pump fiber can extend to 600 W, corresponding to the average pump coupling efficiency of 94.83%. Totally, 2.67-kW output power with the beam quality factor M2 of 1.41 was obtained, using this combiner in the fiber amplifier experimental setup. In addition, the temperature of the splicing region was less than 50.0°C in the designed combiner under the action of circulating cooling water. The experimental results prove that the designed combiner is a promising integrated all-fiber device for multikilowatt continuous-wave fiber laser with excellent beam quality.

  19. Educational Auditing and Quality Assurance. Occasional Paper No. 4.

    ERIC Educational Resources Information Center

    Conner, James E.; Lessinger, Leon M.

    This paper considers how to respond to new requirements for adequate disclosure of the schools' performance to the public. It proposes the use of three powerful constructs--quality control, quality assurance, and an independent educational accomplishment audit (IEAA). The essential elements of quality control are agreeing on and specifying desired…

  20. Quality Assurance--Best Practices for Assessing Online Programs

    ERIC Educational Resources Information Center

    Wang, Qi

    2006-01-01

    Educators have long sought to define quality in education. With the proliferation of distance education and online learning powered by the Internet, the tasks required to assess the quality of online programs become even more challenging. To assist educators and institutions in search of quality assurance methods to continuously improve their…

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