Sample records for current study proposes

  1. Examining Current and Proposed Home Language Surveys in California in Relation to Initial English Language Proficiency Assessment Results: An Exploratory Study

    ERIC Educational Resources Information Center

    Haas, Eric; Tran, Loan; Linquanti, Robert; Bailey, Alison

    2015-01-01

    The purpose of this exploratory study was to examine the extent to which a proposed home language survey in California could better identify possible English learner and multilingual students than the current home language survey. The responses to a proposed and current survey were examined for students registering for kindergarten through grade…

  2. Optimization of Gear Ratio in the Tidal Current Generation System based on Generated Energy

    NASA Astrophysics Data System (ADS)

    Naoi, Kazuhisa; Shiono, Mitsuhiro; Suzuki, Katsuyuki

    It is possible to predict generating power of the tidal current generation, because of the tidal current's periodicity. Tidal current generation is more advantageous than other renewable energy sources, when the tidal current generation system is connected to the power system and operated. In this paper, we propose a method used to optimize the gear ratio and generator capacity, that is fundamental design items in the tidal current generation system which is composed of Darrieus type water turbine and squirrel-cage induction generator coupled with gear. The proposed method is applied to the tidal current generation system including the most large-sized turbine that we have developed and studied. This paper shows optimum gear ratio and generator capacity that make generated energy maximum, and verify effectiveness of the proposed method. The paper also proposes a method of selecting maximum generating current velocity in order to reduce the generator capacity, from the viewpoint of economics.

  3. Testing Alternative Definitions of Chronic Homelessness.

    PubMed

    Byrne, Thomas; Culhane, Dennis P

    2015-09-01

    This study examined the potential impact of a proposed change to the official federal definition of chronic homelessness. Using administrative data from the emergency shelters in a large U.S. city, this study estimated the number of persons identified as chronically homeless under the current definition of chronic homelessness, a proposed new federal definition, and two alternative definitions and examined shelter utilization for each group. Fewer than half as many people were considered chronically homeless under the proposed new federal definition compared with the current definition. Persons considered chronically homeless by the proposed new definition and, to a lesser extent, by the two alternative definitions, made heavier use of shelter compared with persons who met the current definition. A proposed new and two alternative definitions of chronic homelessness are better suited than the existing federal definition for identifying persons with the most protracted experiences of homelessness.

  4. Alternating steady state free precession for estimation of current-induced magnetic flux density: A feasibility study.

    PubMed

    Lee, Hyunyeol; Jeong, Woo Chul; Kim, Hyung Joong; Woo, Eung Je; Park, Jaeseok

    2016-05-01

    To develop a novel, current-controlled alternating steady-state free precession (SSFP)-based conductivity imaging method and corresponding MR signal models to estimate current-induced magnetic flux density (Bz ) and conductivity distribution. In the proposed method, an SSFP pulse sequence, which is in sync with alternating current pulses, produces dual oscillating steady states while yielding nonlinear relation between signal phase and Bz . A ratiometric signal model between the states was analytically derived using the Bloch equation, wherein Bz was estimated by solving a nonlinear inverse problem for conductivity estimation. A theoretical analysis on the signal-to-noise ratio of Bz was given. Numerical and experimental studies were performed using SSFP-FID and SSFP-ECHO with current pulses positioned either before or after signal encoding to investigate the feasibility of the proposed method in conductivity estimation. Given all SSFP variants herein, SSFP-FID with alternating current pulses applied before signal encoding exhibits the highest Bz signal-to-noise ratio and conductivity contrast. Additionally, compared with conventional conductivity imaging, the proposed method benefits from rapid SSFP acquisition without apparent loss of conductivity contrast. We successfully demonstrated the feasibility of the proposed method in estimating current-induced Bz and conductivity distribution. It can be a promising, rapid imaging strategy for quantitative conductivity imaging. © 2015 Wiley Periodicals, Inc.

  5. Theoretical derivation of anodizing current and comparison between fitted curves and measured curves under different conditions.

    PubMed

    Chong, Bin; Yu, Dongliang; Jin, Rong; Wang, Yang; Li, Dongdong; Song, Ye; Gao, Mingqi; Zhu, Xufei

    2015-04-10

    Anodic TiO2 nanotubes have been studied extensively for many years. However, the growth kinetics still remains unclear. The systematic study of the current transient under constant anodizing voltage has not been mentioned in the original literature. Here, a derivation and its corresponding theoretical formula are proposed to overcome this challenge. In this paper, the theoretical expressions for the time dependent ionic current and electronic current are derived to explore the anodizing process of Ti. The anodizing current-time curves under different anodizing voltages and different temperatures are experimentally investigated in the anodization of Ti. Furthermore, the quantitative relationship between the thickness of the barrier layer and anodizing time, and the relationships between the ionic/electronic current and temperatures are proposed in this paper. All of the current-transient plots can be fitted consistently by the proposed theoretical expressions. Additionally, it is the first time that the coefficient A of the exponential relationship (ionic current j(ion) = A exp(BE)) has been determined under various temperatures and voltages. And the results indicate that as temperature and voltage increase, ionic current and electronic current both increase. The temperature has a larger effect on electronic current than ionic current. These results can promote the research of kinetics from a qualitative to quantitative level.

  6. Theoretical derivation of anodizing current and comparison between fitted curves and measured curves under different conditions

    NASA Astrophysics Data System (ADS)

    Chong, Bin; Yu, Dongliang; Jin, Rong; Wang, Yang; Li, Dongdong; Song, Ye; Gao, Mingqi; Zhu, Xufei

    2015-04-01

    Anodic TiO2 nanotubes have been studied extensively for many years. However, the growth kinetics still remains unclear. The systematic study of the current transient under constant anodizing voltage has not been mentioned in the original literature. Here, a derivation and its corresponding theoretical formula are proposed to overcome this challenge. In this paper, the theoretical expressions for the time dependent ionic current and electronic current are derived to explore the anodizing process of Ti. The anodizing current-time curves under different anodizing voltages and different temperatures are experimentally investigated in the anodization of Ti. Furthermore, the quantitative relationship between the thickness of the barrier layer and anodizing time, and the relationships between the ionic/electronic current and temperatures are proposed in this paper. All of the current-transient plots can be fitted consistently by the proposed theoretical expressions. Additionally, it is the first time that the coefficient A of the exponential relationship (ionic current jion = A exp(BE)) has been determined under various temperatures and voltages. And the results indicate that as temperature and voltage increase, ionic current and electronic current both increase. The temperature has a larger effect on electronic current than ionic current. These results can promote the research of kinetics from a qualitative to quantitative level.

  7. Impact of a proposed revision of the IESTI equation on the acute risk assessment conducted when setting maximum residue levels (MRLs) in the European Union (EU): A case study.

    PubMed

    Breysse, Nicolas; Vial, Gaelle; Pattingre, Lauriane; Ossendorp, Bernadette C; Mahieu, Karin; Reich, Hermine; Rietveld, Anton; Sieke, Christian; van der Velde-Koerts, Trijntje; Sarda, Xavier

    2018-06-03

    Proposals to update the methodology for the international estimated short-term intake (IESTI) equations were made during an international workshop held in Geneva in 2015. Changes to several parameters of the current four IESTI equations (cases 1, 2a, 2b, and 3) were proposed. In this study, the overall impact of these proposed changes on estimates of short-term exposure was studied using the large portion data available in the European Food Safety Authority PRIMo model and the residue data submitted in the framework of the European Maximum Residue Levels (MRL) review under Article 12 of Regulation (EC) No 396/2005. Evaluation of consumer exposure using the current and proposed equations resulted in substantial differences in the exposure estimates; however, there were no significant changes regarding the number of accepted MRLs. For the different IESTI cases, the median ratio of the new versus the current equation is 1.1 for case 1, 1.4 for case 2a, 0.75 for case 2b, and 1 for case 3. The impact, expressed as a shift in the IESTI distribution profile, indicated that the 95th percentile IESTI shifted from 50% of the acute reference dose (ARfD) with the current equations to 65% of the ARfD with the proposed equations. This IESTI increase resulted in the loss of 1.2% of the MRLs (37 out of 3110) tested within this study. At the same time, the proposed equations would have allowed 0.4% of the MRLs (14 out of 3110) that were rejected with the current equations to be accepted. The commodity groups that were most impacted by these modifications are solanacea (e.g., potato, eggplant), lettuces, pulses (dry), leafy brassica (e.g., kale, Chinese cabbage), and pome fruits. The active substances that were most affected were fluazifop-p-butyl, deltamethrin, and lambda-cyhalothrin.

  8. Superstatistics analysis of the ion current distribution function: Met3PbCl influence study.

    PubMed

    Miśkiewicz, Janusz; Trela, Zenon; Przestalski, Stanisław; Karcz, Waldemar

    2010-09-01

    A novel analysis of ion current time series is proposed. It is shown that higher (second, third and fourth) statistical moments of the ion current probability distribution function (PDF) can yield new information about ion channel properties. The method is illustrated on a two-state model where the PDF of the compound states are given by normal distributions. The proposed method was applied to the analysis of the SV cation channels of vacuolar membrane of Beta vulgaris and the influence of trimethyllead chloride (Met(3)PbCl) on the ion current probability distribution. Ion currents were measured by patch-clamp technique. It was shown that Met(3)PbCl influences the variance of the open-state ion current but does not alter the PDF of the closed-state ion current. Incorporation of higher statistical moments into the standard investigation of ion channel properties is proposed.

  9. Phase-locked loop design with fast-digital-calibration charge pump

    NASA Astrophysics Data System (ADS)

    Wang, San-Fu; Hwang, Tsuen-Shiau; Wang, Jhen-Ji

    2016-02-01

    A fast-digital-calibration technique is proposed for reducing current mismatch in the charge pump (CP) of a phase-locked loop (PLL). The current mismatch in the CP generates fluctuations, which is transferred to the input of voltage-controlled oscillator (VCO). Therefore, the current mismatch increases the reference spur in the PLL. Improving current match of CP will reduce the reference spur and decrease the static phase offset of PLLs. Moreover, the settling time, ripple and power consumption of the PLL are also improved by the proposed technique. This study evaluated a 2.27-2.88 GHz frequency synthesiser fabricated in TSMC 0.18 μm CMOS 1.8 V process. The tuning range of proposed VCO is about 26%. By using the fast-digital-calibration technique, current mismatch is reduced to lower than 0.97%, and the operation range of the proposed CP is between 0.2 and 1.6 V. The proposed PLL has a total power consumption of 22.57 mW and a settling time of 10 μs or less.

  10. Research on Parallel Three Phase PWM Converters base on RTDS

    NASA Astrophysics Data System (ADS)

    Xia, Yan; Zou, Jianxiao; Li, Kai; Liu, Jingbo; Tian, Jun

    2018-01-01

    Converters parallel operation can increase capacity of the system, but it may lead to potential zero-sequence circulating current, so the control of circulating current was an important goal in the design of parallel inverters. In this paper, the Real Time Digital Simulator (RTDS) is used to model the converters parallel system in real time and study the circulating current restraining. The equivalent model of two parallel converters and zero-sequence circulating current(ZSCC) were established and analyzed, then a strategy using variable zero vector control was proposed to suppress the circulating current. For two parallel modular converters, hardware-in-the-loop(HIL) study based on RTDS and practical experiment were implemented, results prove that the proposed control strategy is feasible and effective.

  11. Extended score interval in the assessment of basic surgical skills.

    PubMed

    Acosta, Stefan; Sevonius, Dan; Beckman, Anders

    2015-01-01

    The Basic Surgical Skills course uses an assessment score interval of 0-3. An extended score interval, 1-6, was proposed by the Swedish steering committee of the course. The aim of this study was to analyze the trainee scores in the current 0-3 scored version compared to a proposed 1-6 scored version. Sixteen participants, seven females and nine males, were evaluated in the current and proposed assessment forms by instructors, observers, and learners themselves during the first and second day. In each assessment form, 17 tasks were assessed. The inter-rater reliability between the current and the proposed score sheets were evaluated with intraclass correlation (ICC) with 95% confidence intervals (CI). The distribution of scores for 'knot tying' at the last time point and 'bowel anastomosis side to side' given by the instructors in the current assessment form showed that the highest score was given in 31 and 62%, respectively. No ceiling effects were found in the proposed assessment form. The overall ICC between the current and proposed score sheets after assessment by the instructors increased from 0.38 (95% CI 0.77-0.78) on Day 1 to 0.83 (95% CI 0.51-0.94) on Day 2. A clear ceiling effect of scores was demonstrated in the current assessment form, questioning its validity. The proposed score sheet provides more accurate scores and seems to be a better feedback instrument for learning technical surgical skills in the Basic Surgical Skills course.

  12. Extended score interval in the assessment of basic surgical skills.

    PubMed

    Acosta, Stefan; Sevonius, Dan; Beckman, Anders

    2015-01-01

    Introduction The Basic Surgical Skills course uses an assessment score interval of 0-3. An extended score interval, 1-6, was proposed by the Swedish steering committee of the course. The aim of this study was to analyze the trainee scores in the current 0-3 scored version compared to a proposed 1-6 scored version. Methods Sixteen participants, seven females and nine males, were evaluated in the current and proposed assessment forms by instructors, observers, and learners themselves during the first and second day. In each assessment form, 17 tasks were assessed. The inter-rater reliability between the current and the proposed score sheets were evaluated with intraclass correlation (ICC) with 95% confidence intervals (CI). Results The distribution of scores for 'knot tying' at the last time point and 'bowel anastomosis side to side' given by the instructors in the current assessment form showed that the highest score was given in 31 and 62%, respectively. No ceiling effects were found in the proposed assessment form. The overall ICC between the current and proposed score sheets after assessment by the instructors increased from 0.38 (95% CI 0.77-0.78) on Day 1 to 0.83 (95% CI 0.51-0.94) on Day 2. Discussion A clear ceiling effect of scores was demonstrated in the current assessment form, questioning its validity. The proposed score sheet provides more accurate scores and seems to be a better feedback instrument for learning technical surgical skills in the Basic Surgical Skills course.

  13. Motion-induced eddy current thermography for high-speed inspection

    NASA Astrophysics Data System (ADS)

    Wu, Jianbo; Li, Kongjing; Tian, Guiyun; Zhu, Junzhen; Gao, Yunlai; Tang, Chaoqing; Chen, Xiaotian

    2017-08-01

    This letter proposes a novel motion-induced eddy current based thermography (MIECT) for high-speed inspection. In contrast to conventional eddy current thermography (ECT) based on a time-varying magnetic field created by an AC coil, the motion-induced eddy current is induced by the relative motion between magnetic field and inspected objects. A rotating magnetic field created by three-phase windings is used to investigate the heating principle and feasibility of the proposed method. Firstly, based on Faraday's law the distribution of MIEC is investigated, which is then validated by numerical simulation. Further, experimental studies are conducted to validate the proposed method by creating rotating magnetic fields at different speeds from 600 rpm to 6000 rpm, and it is verified that rotating speed will increase MIEC intensity and thereafter improve the heating efficiency. The conclusion can be preliminarily drawn that the proposed MIECT is a platform suitable for high-speed inspection.

  14. 28 CFR 512.12 - Content of research proposal.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Content of research proposal. 512.12... ADMINISTRATION RESEARCH Research § 512.12 Content of research proposal. When submitting a research proposal, the... current affiliation(s) of the researcher(s); (2) Title of the study; (3) Purpose of the project; (4...

  15. 28 CFR 512.12 - Content of research proposal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Content of research proposal. 512.12... ADMINISTRATION RESEARCH Research § 512.12 Content of research proposal. When submitting a research proposal, the... current affiliation(s) of the researcher(s); (2) Title of the study; (3) Purpose of the project; (4...

  16. Eurpoean Union bulk tank SCC standards and proposed US standards: Compliance based on data from four Federal Milk Marketing Orders

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to evaluate the percentage of US producers and milk not currently meeting the proposed bulk tank somatic cell counts (BTSCC) limits. Five different limits of BTSCC were evaluated for compliance: 750K, 600K, 500K, and 400K using the current US methods and 400K using th...

  17. Comparing Symptoms of Autism Spectrum Disorders Using the Current "DSM-IV-TR" Diagnostic Criteria and the Proposed "DSM-V" Diagnostic Criteria

    ERIC Educational Resources Information Center

    Worley, Julie A.; Matson, Johnny L.

    2012-01-01

    The American Psychiatric Association has proposed major revisions for the diagnostic category encompassing Autism Spectrum Disorders (ASD), which will reportedly increase the specificity and maintain the sensitivity of diagnoses. As a result, the aim of the current study was to compare symptoms of ASD in children and adolescents (N = 208) who met…

  18. Visibility analysis of fire lookout towers in the Boyabat State Forest Enterprise in Turkey.

    PubMed

    Kucuk, Omer; Topaloglu, Ozer; Altunel, Arif Oguz; Cetin, Mehmet

    2017-07-01

    For a successful fire suppression, it is essential to detect and intervene forest fires as early as possible. Fire lookout towers are crucial assets in detecting forest fires, in addition to other technological advancements. In this study, we performed a visibility analysis on a network of fire lookout towers currently operating in a relatively fire-prone region in Turkey's Western Black Sea region. Some of these towers had not been functioning properly; it was proposed that these be taken out of the grid and replaced with new ones. The percentage of visible areas under the current network of fire lookout towers was 73%; it could rise to 81% with the addition of newly proposed towers. This study was the first research to conduct a visibility analysis of current and newly proposed fire lookout towers in the Western Black Sea region and focus on its forest fire problem.

  19. Current Conveyor All-Pass Sections: Brief Review and Novel Solution

    PubMed Central

    Maheshwari, Sudhanshu

    2013-01-01

    This study relates to the review of an important analog electronic function in form of all-pass filter's realization using assorted current conveyor types and their relative performances, which resulted in a novel solution based on a new proposed active element. The study encompasses notable proposals during last the decade or more, and provides a platform for a broader future survey on the topic for enhancing the knowledge penetration amongst the researchers in the specified field. A new active element named EXCCII (Extra-X second generation current conveyor) with buffered output is found in the study along with its use in a new first-order all-pass section, with possible realization using commercially available IC (AD-844) and results. PMID:24379741

  20. Simulation study and experimental results for detection and classification of the transient capacitor inrush current using discrete wavelet transform and artificial intelligence

    NASA Astrophysics Data System (ADS)

    Patcharoen, Theerasak; Yoomak, Suntiti; Ngaopitakkul, Atthapol; Pothisarn, Chaichan

    2018-04-01

    This paper describes the combination of discrete wavelet transforms (DWT) and artificial intelligence (AI), which are efficient techniques to identify the type of inrush current, analyze the origin and possible cause on the capacitor bank switching. The experiment setup used to verify the proposed techniques can be detected and classified the transient inrush current from normal capacitor rated current. The discrete wavelet transforms are used to detect and classify the inrush current. Then, output from wavelet is acted as input of fuzzy inference system for discriminating the type of switching transient inrush current. The proposed technique shows enhanced performance with a discrimination accuracy of 90.57%. Both simulation study and experimental results are quite satisfactory with providing the high accuracy and reliability which can be developed and implemented into a numerical overcurrent (50/51) and unbalanced current (60C) protection relay for an application of shunt capacitor bank protection in the future.

  1. Analysis and numerical modelling of eddy current damper for vibration problems

    NASA Astrophysics Data System (ADS)

    Irazu, L.; Elejabarrieta, M. J.

    2018-07-01

    This work discusses a contactless eddy current damper, which is used to attenuate structural vibration. Eddy currents can remove energy from dynamic systems without any contact and, thus, without adding mass or modifying the rigidity of the structure. An experimental modal analysis of a cantilever beam in the absence of and under a partial magnetic field is conducted in the bandwidth of 01 kHz. The results show that the eddy current phenomenon can attenuate the vibration of the entire structure without modifying the natural frequencies or the mode shapes of the structure itself. In this study, a new inverse method to numerically determine the dynamic properties of the contactless eddy current damper is proposed. The proposed inverse method and the eddy current model based on a lineal viscous force are validated by a practical application. The numerically obtained transfer function correlates with the experimental one, thus showing good agreement in the entire bandwidth of 01 kHz. The proposed method provides an easy and quick tool to model and predict the dynamic behaviour of the contactless eddy current damper, thereby avoiding the use of complex analytical models.

  2. Marginal regression approach for additive hazards models with clustered current status data.

    PubMed

    Su, Pei-Fang; Chi, Yunchan

    2014-01-15

    Current status data arise naturally from tumorigenicity experiments, epidemiology studies, biomedicine, econometrics and demographic and sociology studies. Moreover, clustered current status data may occur with animals from the same litter in tumorigenicity experiments or with subjects from the same family in epidemiology studies. Because the only information extracted from current status data is whether the survival times are before or after the monitoring or censoring times, the nonparametric maximum likelihood estimator of survival function converges at a rate of n(1/3) to a complicated limiting distribution. Hence, semiparametric regression models such as the additive hazards model have been extended for independent current status data to derive the test statistics, whose distributions converge at a rate of n(1/2) , for testing the regression parameters. However, a straightforward application of these statistical methods to clustered current status data is not appropriate because intracluster correlation needs to be taken into account. Therefore, this paper proposes two estimating functions for estimating the parameters in the additive hazards model for clustered current status data. The comparative results from simulation studies are presented, and the application of the proposed estimating functions to one real data set is illustrated. Copyright © 2013 John Wiley & Sons, Ltd.

  3. Different approaches to overcome uncertainties of production systems

    NASA Astrophysics Data System (ADS)

    Azizi, Amir; Sorooshian, Shahryar

    2015-05-01

    This study presented a comprehensive review on the understanding of uncertainty and the current approaches that have been proposed to handle the uncertainties in the production systems. This paper classified proposed approaches into 11 groups. The paper studied 114 scholarly papers through various international journals. The paper added the latest findings to the body of knowledge to the current reservoir of understanding of the production uncertainties. Thus, the paper prepared the needs of researchers and practitioners for easy references in this area. This review also provided an excellent source to continue further studies on how to deal with the uncertainties of production system.

  4. 49 CFR 1139.3 - Cost study.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... service units as developed from its traffic study. Operating ratios shall be determined for the issue... anticipated on the effective date of the proposed rates, with a separation indicating projected operating ratios on two bases, namely, “based on current revenues,” and “based on proposed revenues”. Operating...

  5. 49 CFR 1139.3 - Cost study.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... service units as developed from its traffic study. Operating ratios shall be determined for the issue... anticipated on the effective date of the proposed rates, with a separation indicating projected operating ratios on two bases, namely, “based on current revenues,” and “based on proposed revenues”. Operating...

  6. 49 CFR 1139.3 - Cost study.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... service units as developed from its traffic study. Operating ratios shall be determined for the issue... anticipated on the effective date of the proposed rates, with a separation indicating projected operating ratios on two bases, namely, “based on current revenues,” and “based on proposed revenues”. Operating...

  7. Kidney transplantation in the elderly.

    PubMed

    Singh, Neeraj; Nori, Uday; Pesavento, Todd

    2009-08-01

    Recent outcome data, ongoing organ shortage and proposed changes in allocation policies are driving the need to review current practices and possible future course of kidney transplantation in the elderly patients. A proposed new kidney allocation system based on matching donor and recipient characteristics to enable 'age-matched' kidney allocation is currently being discussed in the USA. While this system benefits younger recipients, implications for elderly recipients receiving older grafts remain a matter of debate. Despite improved outcomes, there remain significant challenges to kidney transplantation in the elderly, including organ shortage, poor transplant rate, evolving allocation policies, high wait-list mortality and nonstandardized immunosuppression. Prospective studies are needed to evaluate the strategies to meet these challenges and to study the impact of proposed new allocation system.

  8. Directly amplified redox sensor for on-chip chemical analysis

    NASA Astrophysics Data System (ADS)

    Takahashi, Sou; Futagawa, Masato; Ishida, Makoto; Sawada, Kazuaki

    2014-03-01

    In recent years, many groups have studied redox sensors for chemical analysis. A redox sensor has certain powerful advantages, such as its ability to detect multiple ions inside the sensing area, and its ability to measure concentrations of materials by using voltage and current signals. However, the output current signal of a redox sensor decreases when either concentration or sensing area decreases. Therefore, we propose the use of an amplified redox sensor (ARS) for measuring small current signals. The proposed sensor consists of a working electrode combined with a bipolar transistor. In this study, we fabricated an ARS sensor and performed low-concentration measurements using current signal amplification with an integrated bipolar transistor. The sensor chip successfully detected a potassium ferricyanide (K3[Fe(CN)6]) concentration of as low as 10 µM using cyclic voltammetry.

  9. 75 FR 77880 - Proposed Collection; Comment Request; GuLF Worker Study: Gulf Long-Term Follow-Up Study for Oil...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... Request: New. Need and Use of Information Collection: The purpose of the GuLF Study is to investigate... Request; GuLF Worker Study: Gulf Long-Term Follow-Up Study for Oil Spill Clean-Up Workers and Volunteers... instruments display a currently valid OMB control number. Proposed Collection Title: GuLF Worker Study: Gulf...

  10. The impact of endorsing Spitzer's proposed criteria for PTSD in the forthcoming DSM-V on male and female Veterans.

    PubMed

    Miller, Lyndsey N; Chard, Kathleen M; Schumm, Jeremiah A; O'Brien, Carol

    2011-06-01

    This study explored differences between Spitzer's proposed model of posttraumatic stress disorder (PTSD) and the current DSM-IV diagnostic classification scheme in 353 Veterans. The majority of Veterans (89%) diagnosed with PTSD as specified in the DSM-IV also met Spitzer's proposed criteria. Veterans who met both DSM-IV and Spitzer's proposed criteria had significantly higher Clinician Administered PTSD Scale severity scores than Veterans only meeting DSM-IV criteria. Logistic regression indicated that being African American and having no comorbid diagnosis of major depressive disorder or history of a substance use disorder were found to predict those Veterans who met current, but not proposed criteria. These findings have important implications regarding proposed changes to the diagnostic classification criteria for PTSD in the forthcoming DSM-V. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. A Study to Compare the Failure Rates of Current Space Shuttle Ground Support Equipment with the New Pathfinder Equipment and Investigate the Effect that the Proposed GSE Infrastructure Upgrade Might Have to Reduce GSE Infrastructure Failures

    NASA Technical Reports Server (NTRS)

    Kennedy, Barbara J.

    2004-01-01

    The purposes of this study are to compare the current Space Shuttle Ground Support Equipment (GSE) infrastructure with the proposed GSE infrastructure upgrade modification. The methodology will include analyzing the first prototype installation equipment at Launch PAD B called the "Pathfinder". This study will begin by comparing the failure rate of the current components associated with the "Hardware interface module (HIM)" at the Kennedy Space Center to the failure rate of the neW Pathfinder components. Quantitative data will be gathered specifically on HIM components and the PAD B Hypergolic Fuel facility and Hypergolic Oxidizer facility areas which has the upgraded pathfinder equipment installed. The proposed upgrades include utilizing industrial controlled modules, software, and a fiber optic network. The results of this study provide evidence that there is a significant difference in the failure rates of the two studied infrastructure equipment components. There is also evidence that the support staff for each infrastructure system is not equal. A recommendation to continue with future upgrades is based on a significant reduction of failures in the new' installed ground system components.

  12. Quantile Regression Models for Current Status Data

    PubMed Central

    Ou, Fang-Shu; Zeng, Donglin; Cai, Jianwen

    2016-01-01

    Current status data arise frequently in demography, epidemiology, and econometrics where the exact failure time cannot be determined but is only known to have occurred before or after a known observation time. We propose a quantile regression model to analyze current status data, because it does not require distributional assumptions and the coefficients can be interpreted as direct regression effects on the distribution of failure time in the original time scale. Our model assumes that the conditional quantile of failure time is a linear function of covariates. We assume conditional independence between the failure time and observation time. An M-estimator is developed for parameter estimation which is computed using the concave-convex procedure and its confidence intervals are constructed using a subsampling method. Asymptotic properties for the estimator are derived and proven using modern empirical process theory. The small sample performance of the proposed method is demonstrated via simulation studies. Finally, we apply the proposed method to analyze data from the Mayo Clinic Study of Aging. PMID:27994307

  13. Electroencephalogram-based decoding cognitive states using convolutional neural network and likelihood ratio based score fusion.

    PubMed

    Zafar, Raheel; Dass, Sarat C; Malik, Aamir Saeed

    2017-01-01

    Electroencephalogram (EEG)-based decoding human brain activity is challenging, owing to the low spatial resolution of EEG. However, EEG is an important technique, especially for brain-computer interface applications. In this study, a novel algorithm is proposed to decode brain activity associated with different types of images. In this hybrid algorithm, convolutional neural network is modified for the extraction of features, a t-test is used for the selection of significant features and likelihood ratio-based score fusion is used for the prediction of brain activity. The proposed algorithm takes input data from multichannel EEG time-series, which is also known as multivariate pattern analysis. Comprehensive analysis was conducted using data from 30 participants. The results from the proposed method are compared with current recognized feature extraction and classification/prediction techniques. The wavelet transform-support vector machine method is the most popular currently used feature extraction and prediction method. This method showed an accuracy of 65.7%. However, the proposed method predicts the novel data with improved accuracy of 79.9%. In conclusion, the proposed algorithm outperformed the current feature extraction and prediction method.

  14. 77 FR 35408 - Proposed Collection; Comment Request: Opinions and Perspectives About the Current Blood Donation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... the written comments supported the study goals and design as proposed. Three of the written comments... result, content pertaining to the sexual histories of survey respondents was expanded to inform the... Donor Study (REDS), when anonymously surveyed by paper and pencil mailed surveys, 1.2% of male blood...

  15. Characterization of the IMF By-dependent field-aligned currents in the cleft region based on DE 2 observations

    NASA Technical Reports Server (NTRS)

    Taguchi, S.; Sugiura, M.; Winningham, J. D.; Slavin, J. A.

    1993-01-01

    The magnetic field and plasma data from 47 passes of DE-2 are used to study the IMF By-dependent distribution of field-aligned currents in the cleft region. It is proposed that the low-latitude cleft current (LCC) region is not an extension of the region 1 or region 2 current system and that a pair of LCCs and high-latitude cleft currents (HCCs) constitutes the cleft field-aligned current regime. The proposed pair of cleft field-aligned currents is explained with a qualitative model in which this pair of currents is generated on open field lines that have just been reconnected on the dayside magnetopause. The electric fields are transmitted along the field lines to the ionosphere, creating a poleward electric field and a pair of field-aligned currents when By is positive; the pair of field-aligned currents consists of a downward current at lower latitudes and an upward current at higher latitudes. In the By negative case, the model explains the reversal of the field-aligned current direction in the LCC and HCC regions.

  16. Inclinometer--time-domain reflectometry comparative study : research implementation plan.

    DOT National Transportation Integrated Search

    2005-10-01

    ODOT currently uses slope indicator probing to analyze subsurface conditions at roadway landslide : locations. However, the current method is subject to several limitations, and time domain reflectometry : (TDR) has been proposed as an alternative to...

  17. Analysis of series resonant converter with series-parallel connection

    NASA Astrophysics Data System (ADS)

    Lin, Bor-Ren; Huang, Chien-Lan

    2011-02-01

    In this study, a parallel inductor-inductor-capacitor (LLC) resonant converter series-connected on the primary side and parallel-connected on the secondary side is presented for server power supply systems. Based on series resonant behaviour, the power metal-oxide-semiconductor field-effect transistors are turned on at zero voltage switching and the rectifier diodes are turned off at zero current switching. Thus, the switching losses on the power semiconductors are reduced. In the proposed converter, the primary windings of the two LLC converters are connected in series. Thus, the two converters have the same primary currents to ensure that they can supply the balance load current. On the output side, two LLC converters are connected in parallel to share the load current and to reduce the current stress on the secondary windings and the rectifier diodes. In this article, the principle of operation, steady-state analysis and design considerations of the proposed converter are provided and discussed. Experiments with a laboratory prototype with a 24 V/21 A output for server power supply were performed to verify the effectiveness of the proposed converter.

  18. An evaluation of the proposed organisation restructuring at Kadoma city, 2015.

    PubMed

    Muringazuva, A Caroline; Chirundu, Daniel; Shamu, Shepherd; Shambira, Gerald; Gombe, Notion; Juru, Tsitsi; Bangure, Donewell; Tshimanga, Mufuta

    2017-01-01

    Restructuring is the corporate management term for the act of reorganizing the legal, operational, or other structures of a company for the purpose of making it more profitable or better organized for its present needs. However, preparing an organization to accept and welcome any change is crucial. There is concern though over poor service delivery, untimely payment of workers, top management structure which is thought to be top heavy and employee costs taking (58%) of total expenditure. A descriptive cross sectional study was carried out. A cost benefit analysis was used to assess the cost and benefits of the proposed retrenchment exercise. A descriptive cross sectional study survey was conducted to assess the workers' perceptions towards the proposed restructuring exercise. A pretested self-administered questionnaire was used for data collection and data were analysed using EpiInfoTM (CDC 2012).Written informed consent was obtained from all study participants. Sixty nine percent of the respondents were males. The median years working for the organisation was 8 years (Q1=1; Q3=17). The total income was surpassed by expenditure with USD$11 000 and 52% of expenditures was going towards employment costs. A midyear financial review showed that 1% was channeled towards capital expenditure 2% on repairs and maintenance and employee costs accounting to 58% of all incurred expenditure. Current departmental salary budget amounted to USD 3,3million dollars. Estimated salary costs for the proposed departmental structures amount to USD 3,8 million dollars. Comparison of the current and proposed structure showed that the proposed structure costs USD$486 000 more. Projected benefits of the proposed structure aims to improve service delivery from 60%-85% . Unlike managers, lower levels workers did not want the exercise to be carried out. The proposed structure has higher costs than the current structure but with more benefits in terms of service delivery. Generally workers perceived restructuring negatively and did not want it done.

  19. An evaluation of the proposed organisation restructuring at Kadoma city, 2015

    PubMed Central

    Muringazuva, A Caroline; Chirundu, Daniel; Shamu, Shepherd; Shambira, Gerald; Gombe, Notion; Juru, Tsitsi; Bangure, Donewell; Tshimanga, Mufuta

    2017-01-01

    Introduction Restructuring is the corporate management term for the act of reorganizing the legal, operational, or other structures of a company for the purpose of making it more profitable or better organized for its present needs. However, preparing an organization to accept and welcome any change is crucial. There is concern though over poor service delivery, untimely payment of workers, top management structure which is thought to be top heavy and employee costs taking (58%) of total expenditure. Methods A descriptive cross sectional study was carried out. A cost benefit analysis was used to assess the cost and benefits of the proposed retrenchment exercise. A descriptive cross sectional study survey was conducted to assess the workers’ perceptions towards the proposed restructuring exercise. A pretested self-administered questionnaire was used for data collection and data were analysed using EpiInfoTM (CDC 2012).Written informed consent was obtained from all study participants. Results Sixty nine percent of the respondents were males. The median years working for the organisation was 8 years (Q1=1; Q3=17). The total income was surpassed by expenditure with USD$11 000 and 52% of expenditures was going towards employment costs. A midyear financial review showed that 1% was channeled towards capital expenditure 2% on repairs and maintenance and employee costs accounting to 58% of all incurred expenditure. Current departmental salary budget amounted to USD 3,3million dollars. Estimated salary costs for the proposed departmental structures amount to USD 3,8 million dollars. Comparison of the current and proposed structure showed that the proposed structure costs USD$486 000 more. Projected benefits of the proposed structure aims to improve service delivery from 60%-85% . Unlike managers, lower levels workers did not want the exercise to be carried out. Conclusion The proposed structure has higher costs than the current structure but with more benefits in terms of service delivery. Generally workers perceived restructuring negatively and did not want it done. PMID:28748021

  20. Suppression of TFT leakage current effect on active matrix displays by employing a new circular switch

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hoon; Park, Hyun-Sang; Jeon, Jae-Hong; Han, Min-Koo

    2008-03-01

    We have proposed a new poly-Si TFT pixel, which can suppress TFT leakage current effect on active matrix organic diode (AMOLED) displays, by employing a new circular switching TFT and additional signal line for compensating the leakage current. When the leakage current of switching TFT is increased, the VGS of the current driving TFT in the proposed pixel is not altered by the variable data voltages due to the circular switching TFT. Our simulation results show that OLED current variation of the proposed pixel can be suppressed less than 3%, while that of conventional pixel exceeds 30%. The proposed pixel may be suitable to suppress the leakage current effect on AMOLED display.

  1. Three-axis orthogonal transceiver coil for eddy current sounding

    NASA Astrophysics Data System (ADS)

    Sukhanov, D.; Zavyalova, K.; Goncharik, M.

    2017-08-01

    We propose the new structure of three-axis transceiver magnetic-induction coil for eddy current probing. Due to the orientation of the coils, the direct signal from the transmitting coil to the receiving coil is minimized, which provided a high dynamic range. Sensitivity in all directions is provided by combining coils of different orientations. Numerical simulation and experimental studies of such a system have been carried out and confirmed the applicability of the proposed method and the mathematical model.

  2. A Comparative Study Concerning Administrative Aspects of Elementary Off-Campus Student Teaching Programs: Current Practices and Proposed Patterns.

    ERIC Educational Resources Information Center

    Armstrong, Robert J.

    A study was made to determine the current status of selected administrative areas of student teaching programs in Massachusetts and cooperative student teaching programs throughout the nation, the desirability of establishing cooperative programs in Massachusetts, and the organization and impelementation of these programs. Specific administrative…

  3. Assigning and Combining Probabilities in Single-Case Studies

    ERIC Educational Resources Information Center

    Manolov, Rumen; Solanas, Antonio

    2012-01-01

    There is currently a considerable diversity of quantitative measures available for summarizing the results in single-case studies. Given that the interpretation of some of them is difficult due to the lack of established benchmarks, the current article proposes an approach for obtaining further numerical evidence on the importance of the results,…

  4. The "Taller de Prácticas Docentes" [Teaching Practice Workshop], a Role-Playing-Based Proposal for Higher Dance Studies

    ERIC Educational Resources Information Center

    Torregrosa Salcedo, Elvira; Roig-Vila, Rosabel; Blasco Mira, Josefa Eugenia

    2017-01-01

    This study focuses on current developments in Higher Dance Studies in Spain. The proposal for a "Taller de Prácticas Docentes" [Teaching Practice Workshop,or TPD by its Spanish acronym] carried out at the Higher Dance Conservatory of Alicante (Spain) and implemented as a pilot experience at this centrebecame our research point of…

  5. Design and Experimental Study of a Current Transformer with a Stacked PCB Based on B-Dot.

    PubMed

    Wang, Jingang; Si, Diancheng; Tian, Tian; Ren, Ran

    2017-04-10

    An electronic current transformer with a B-dot sensor is proposed in this study. The B-dot sensor can realize the current measurement of the transmission line in a non-contact way in accordance with the principle of magnetic field coupling. The multiple electrodes series-opposing structure is applied together with differential input structures and active integrating circuits, which can allow the sensor to operate in differential mode. Maxwell software is adopted to model and simulate the sensor. Optimization of the sensor structural parameters is conducted through finite-element simulation. A test platform is built to conduct the steady-state characteristic, on-off operation, and linearity tests for the designed current transformer under the power-frequency current. As shown by the test results, in contrast with traditional electromagnetic CT, the designed current transformer can achieve high accuracy and good phase-frequency; its linearity is also very good at different distances from the wire. The proposed current transformer provides a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system, thereby satisfying the development demands of the smart power grid.

  6. Design and Experimental Study of a Current Transformer with a Stacked PCB Based on B-Dot

    PubMed Central

    Wang, Jingang; Si, Diancheng; Tian, Tian; Ren, Ran

    2017-01-01

    An electronic current transformer with a B-dot sensor is proposed in this study. The B-dot sensor can realize the current measurement of the transmission line in a non-contact way in accordance with the principle of magnetic field coupling. The multiple electrodes series-opposing structure is applied together with differential input structures and active integrating circuits, which can allow the sensor to operate in differential mode. Maxwell software is adopted to model and simulate the sensor. Optimization of the sensor structural parameters is conducted through finite-element simulation. A test platform is built to conduct the steady-state characteristic, on-off operation, and linearity tests for the designed current transformer under the power-frequency current. As shown by the test results, in contrast with traditional electromagnetic CT, the designed current transformer can achieve high accuracy and good phase-frequency; its linearity is also very good at different distances from the wire. The proposed current transformer provides a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system, thereby satisfying the development demands of the smart power grid. PMID:28394298

  7. Current-induced alternating reversed dual-echo-steady-state for joint estimation of tissue relaxation and electrical properties.

    PubMed

    Lee, Hyunyeol; Sohn, Chul-Ho; Park, Jaeseok

    2017-07-01

    To develop a current-induced, alternating reversed dual-echo-steady-state-based magnetic resonance electrical impedance tomography for joint estimation of tissue relaxation and electrical properties. The proposed method reverses the readout gradient configuration of conventional, in which steady-state-free-precession (SSFP)-ECHO is produced earlier than SSFP-free-induction-decay (FID) while alternating current pulses are applied in between the two SSFPs to secure high sensitivity of SSFP-FID to injection current. Additionally, alternating reversed dual-echo-steady-state signals are modulated by employing variable flip angles over two orthogonal injections of current pulses. Ratiometric signal models are analytically constructed, from which T 1 , T 2 , and current-induced B z are jointly estimated by solving a nonlinear inverse problem for conductivity reconstruction. Numerical simulations and experimental studies are performed to investigate the feasibility of the proposed method in estimating relaxation parameters and conductivity. The proposed method, if compared with conventional magnetic resonance electrical impedance tomography, enables rapid data acquisition and simultaneous estimation of T 1 , T 2 , and current-induced B z , yielding a comparable level of signal-to-noise ratio in the parameter estimates while retaining a relative conductivity contrast. We successfully demonstrated the feasibility of the proposed method in jointly estimating tissue relaxation parameters as well as conductivity distributions. It can be a promising, rapid imaging strategy for quantitative conductivity estimation. Magn Reson Med 78:107-120, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  8. Electroencephalogram-based decoding cognitive states using convolutional neural network and likelihood ratio based score fusion

    PubMed Central

    2017-01-01

    Electroencephalogram (EEG)-based decoding human brain activity is challenging, owing to the low spatial resolution of EEG. However, EEG is an important technique, especially for brain–computer interface applications. In this study, a novel algorithm is proposed to decode brain activity associated with different types of images. In this hybrid algorithm, convolutional neural network is modified for the extraction of features, a t-test is used for the selection of significant features and likelihood ratio-based score fusion is used for the prediction of brain activity. The proposed algorithm takes input data from multichannel EEG time-series, which is also known as multivariate pattern analysis. Comprehensive analysis was conducted using data from 30 participants. The results from the proposed method are compared with current recognized feature extraction and classification/prediction techniques. The wavelet transform-support vector machine method is the most popular currently used feature extraction and prediction method. This method showed an accuracy of 65.7%. However, the proposed method predicts the novel data with improved accuracy of 79.9%. In conclusion, the proposed algorithm outperformed the current feature extraction and prediction method. PMID:28558002

  9. External validation of the proposed T and N categories of squamous cell carcinoma of the penis.

    PubMed

    Al-Najar, Amr; Alkatout, Ibrahim; Al-Sanabani, Sakhr; Korda, Joanna Beate; Hegele, Axel; Bolenz, Christian; Jünemann, Klaus-Peter; Naumann, Carsten Maik

    2011-04-01

    The aim of this study was to validate recently proposed modifications to the current TNM classification of penile squamous cell carcinoma (PSCC) by using data from four German urological centers. We identified 89 patients treated for histologically confirmed PSCC between 1996 and 2008 and reclassified them according to the proposed TNM staging revisions. The proposed changes restricted T2 to tumoral invasion of the corpus spongiosum, whereas invasion of the corpus cavernosum was considered as T3. No changes were made to T1 and T4. Furthermore, N1 was limited to unilateral and N2 to bilateral inguinal lymph node involvement regardless of their number. Pelvic lymph node involvement and fixed lymph node were considered as N3 tumors. The range of follow up after initial treatment was 1-142 months (mean 38). Node-negative cases following the current classification were 65.2% (30/46), 48.5% (16/33) and 87.5% (7/8) for T1, T2 and T3, respectively. According to the proposed classification, N0 cases were markedly reduced in the T3 group (55.5%, 10/18) and relatively changed in the T2 group (56.5%, 13/23). T4 patients had no negative disease status. The 3-year disease-specific survival (DSS) rates for the proposed categories were 85.4%, 71.6% and 62.4% for T1, T2 and T3, respectively. For the current categories, the 3-year DSS rates were 85.4%, 66.9% and 100% for T1, T2 and T3, respectively. The 3-year DSS of the current N categories was 78.7%, 51% and 13.3% for N1, N2 and N3, respectively. According to the newly proposed categories, the 3-year DSS was 70%, 50% and 13.3% for N1, N2 and N3, respectively. Tumor and nodal staging of the newly proposed TNM classification show a more distinctive survival compared to the current one. However, a multi-institutional validation is still required to further corroborate the proposed modifications. © 2011 The Japanese Urological Association.

  10. Computerized PET/CT image analysis in the evaluation of tumour response to therapy

    PubMed Central

    Wang, J; Zhang, H H

    2015-01-01

    Current cancer therapy strategy is mostly population based, however, there are large differences in tumour response among patients. It is therefore important for treating physicians to know individual tumour response. In recent years, many studies proposed the use of computerized positron emission tomography/CT image analysis in the evaluation of tumour response. Results showed that computerized analysis overcame some major limitations of current qualitative and semiquantitative analysis and led to improved accuracy. In this review, we summarize these studies in four steps of the analysis: image registration, tumour segmentation, image feature extraction and response evaluation. Future works are proposed and challenges described. PMID:25723599

  11. Resonant Tunneling Spin Pump

    NASA Technical Reports Server (NTRS)

    Ting, David Z.

    2007-01-01

    The resonant tunneling spin pump is a proposed semiconductor device that would generate spin-polarized electron currents. The resonant tunneling spin pump would be a purely electrical device in the sense that it would not contain any magnetic material and would not rely on an applied magnetic field. Also, unlike prior sources of spin-polarized electron currents, the proposed device would not depend on a source of circularly polarized light. The proposed semiconductor electron-spin filters would exploit the Rashba effect, which can induce energy splitting in what would otherwise be degenerate quantum states, caused by a spin-orbit interaction in conjunction with a structural-inversion asymmetry in the presence of interfacial electric fields in a semiconductor heterostructure. The magnitude of the energy split is proportional to the electron wave number. Theoretical studies have suggested the possibility of devices in which electron energy states would be split by the Rashba effect and spin-polarized currents would be extracted by resonant quantum-mechanical tunneling.

  12. Performance evaluation of a modular detector unit for X-ray computed tomography.

    PubMed

    Guo, Zhe; Tang, Zhiwei; Wang, Xinzeng; Deng, Mingliang; Hu, Guangshu; Zhang, Hui

    2013-04-18

    A research prototype CT scanner is currently under development in our lab. One of the key components in this project is the CT detector. This paper describes the design and performance evaluation of the modular CT detector unit for our proposed scanner. It consists of a Photodiode Array Assembly which captures irradiating X-ray photons and converts the energy into electrical current, and a mini Data Acquisition System which performs current integration and converts the analog signal into digital samples. The detector unit can be easily tiled together to form a CT detector. Experiments were conducted to characterize the detector performance both at the single unit level and system level. The noise level, linearity and uniformity of the proposed detector unit were reported and initial imaging studies were also presented which demonstrated the potential application of the proposed detector unit in actual CT scanners.

  13. Identification of linearised RMS-voltage dip patterns based on clustering in renewable plants

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

    García-Sánchez, Tania; Gómez-Lázaro, Emilio; Muljadi, Edward

    Generation units connected to the grid are currently required to meet low-voltage ride-through (LVRT) requirements. In most developed countries, these requirements also apply to renewable sources, mainly wind power plants and photovoltaic installations connected to the grid. This study proposes an alternative characterisation solution to classify and visualise a large number of collected events in light of current limits and requirements. The authors' approach is based on linearised root-mean-square-(RMS)-voltage trajectories, taking into account LRVT requirements, and a clustering process to identify the most likely pattern trajectories. The proposed solution gives extensive information on an event's severity by providing a simplemore » but complete visualisation of the linearised RMS-voltage patterns. In addition, these patterns are compared to current LVRT requirements to determine similarities or discrepancies. A large number of collected events can then be automatically classified and visualised for comparative purposes. Real disturbances collected from renewable sources in Spain are used to assess the proposed solution. Extensive results and discussions are also included in this study.« less

  14. Validating the Proposed Structure of the Relationships among Test Anxiety and Its Predictors Based on Control-Value Theory: Evidence for Gender-Specific Patterns

    ERIC Educational Resources Information Center

    Ringeisen, Tobias; Raufelder, Diana; Schnell, Kerstin; Rohrmann, Sonja

    2016-01-01

    Control-value theory (CVT) proposes a framework for the structure of the relationships between the various predictors of achievement-related emotions, particularly anxiety. Despite existing evidence for the role of anxiety predictors, research has not yet justified their proposed structure. Hence, the current study validated the structure of test…

  15. 77 FR 46748 - Notice of Proposed Information Collection Requests; Institute of Education Sciences; Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-06

    ... DEPARTMENT OF EDUCATION Notice of Proposed Information Collection Requests; Institute of Education Sciences; Impact Evaluation of Teacher and Leader Evaluation Systems SUMMARY: This study provides important implementation and impact information on the kinds of performance evaluation systems currently discussed in...

  16. Electromigration failures under bidirectional current stress

    NASA Astrophysics Data System (ADS)

    Tao, Jiang; Cheung, Nathan W.; Hu, Chenming

    1998-01-01

    Electromigration failure under DC stress has been studied for more than 30 years, and the methodologies for accelerated DC testing and design rules have been well established in the IC industry. However, the electromigration behavior and design rules under time-varying current stress are still unclear. In CMOS circuits, as many interconnects carry pulsed-DC (local VCC and VSS lines) and bidirectional AC current (clock and signal lines), it is essential to assess the reliability of metallization systems under these conditions. Failure mechanisms of different metallization systems (Al-Si, Al-Cu, Cu, TiN/Al-alloy/TiN, etc.) and different metallization structures (via, plug and interconnect) under AC current stress in a wide frequency range (from mHz to 500 MHz) has been study in this paper. Based on these experimental results, a damage healing model is developed, and electromigration design rules are proposed. It shows that in the circuit operating frequency range, the "design-rule current" is the time-average current. The pure AC component of the current only contributes to self-heating, while the average (DC component) current contributes to electromigration. To ensure longer thermal-migration lifetime under high frequency AC stress, an additional design rule is proposed to limit the temperature rise due to self-joule heating.

  17. Measuring Joule heating and strain induced by electrical current with Moire interferometry

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

    Chen Bicheng; Basaran, Cemal

    2011-04-01

    This study proposes a new method to locate and measure the temperature of the hot spots caused by Joule Heating by measuring the free thermal expansion in-plane strain. It is demonstrated that the hotspot caused by the Joule heating in a thin metal film/plate structure can be measured by Phase shifting Moire interferometry with continuous wavelet transform (PSMI/CWT) at the microscopic scale. A demonstration on a copper film is conducted to verify the theory under different current densities. A correlation between the current density and strain in two orthogonal directions (one in the direction of the current flow) is proposed.more » The method can also be used for the measurement of the Joule heating in the microscopic solid structures in the electronic packaging devices. It is shown that a linear relationship exists between current density squared and normal strains.« less

  18. A Method to Analyze How Various Parts of Clouds Influence Each Other's Brightness

    NASA Technical Reports Server (NTRS)

    Varnai, Tamas; Marshak, Alexander; Lau, William (Technical Monitor)

    2001-01-01

    This paper proposes a method for obtaining new information on 3D radiative effects that arise from horizontal radiative interactions in heterogeneous clouds. Unlike current radiative transfer models, it can not only calculate how 3D effects change radiative quantities at any given point, but can also determine which areas contribute to these 3D effects, to what degree, and through what mechanisms. After describing the proposed method, the paper illustrates its new capabilities both for detailed case studies and for the statistical processing of large datasets. Because the proposed method makes it possible, for the first time, to link a particular change in cloud properties to the resulting 3D effect, in future studies it can be used to develop new radiative transfer parameterizations that would consider 3D effects in practical applications currently limited to 1D theory-such as remote sensing of cloud properties and dynamical cloud modeling.

  19. Electrode pattern design for GaAs betavoltaic batteries

    NASA Astrophysics Data System (ADS)

    Haiyang, Chen; Jianhua, Yin; Darang, Li

    2011-08-01

    The sensitivities of betavoltaic batteries and photovoltaic batteries to series and parallel resistance are studied. Based on the study, an electrode pattern design principle of GaAs betavoltaic batteries is proposed. GaAs PIN junctions with and without the proposed electrode pattern are fabricated and measured under the illumination of 63Ni. Results show that the proposed electrode can reduce the backscattering and shadowing for the beta particles from 63Ni to increase the GaAs betavoltaic battery short circuit currents effectively but has little impact on the fill factors and ideal factors.

  20. Inverting Quasi-Resonant Switched-Capacitor Bidirectional Converter and Its Application to Battery Equalization

    NASA Astrophysics Data System (ADS)

    Lee, Yuang-Shung; Chiu, Yin-Yuan; Cheng, Ming-Wang; Ko, Yi-Pin; Hsiao, Sung-Hsin

    The proposed quasi-resonant (QR) zero current switching (ZCS) switched-capacitor (SC) converter is a new type of bidirectional power flow control conversion scheme. The proposed converter is able to provide voltage conversion ratios from -3/-{1 \\over 3} (triple-mode/trisection-mode) to -n/-{1 \\over n} (-n-mode/-{1 \\over n}-mode) by adding a different number of switched-capacitors and power MOSFET switches with a small series connected resonant inductor for forward and reverse power flow control schemes. It possesses the advantages of low switching losses and current stress in this QR ZCS SC converter. The principle of operation, theoretical analysis of the proposed triple-mode/trisection-mode bidirectional power conversion scheme is described in detail with circuit model analysis. Simulation and experimental studies are carried out to verify the performance of the proposed inverting type ZCS SC QR bidirectional converter. The proposed converters can be applied to battery equalization for battery management system (BMS).

  1. A pre-heating method based on sinusoidal alternating current for lithium-ion battery

    NASA Astrophysics Data System (ADS)

    Fan, Wentao; Sun, Fengchun; Guo, Shanshan

    2018-04-01

    In this paper, a method of low temperature pre-heating of sinusoidal alternating current (SAC) is proposed. Generally, the lower the frequency of the AC current, the higher the heat generation rate. Yet at low frequency, there is a risk of lithium-ion deposition during the half cycle of charging. This study develops a temperature-adaptive, deposition-free AC pre-heating method. a equivalent electric circuit(EEC) model is established to predict the heat generation rate and temperature status, whose parameters are calibrated from the EIS impedance measurements. The effects of current frequency and amplitude on the heating effect are investigated respectively. A multistep temperature-adaptive amplitude strategy is proposed and the cell can be heated from -20°C to 5°C within 509s at 100Hz frequency with this method.

  2. A soft switching with reduced voltage stress ZVT-PWM full-bridge converter

    NASA Astrophysics Data System (ADS)

    Sahin, Yakup; Ting, Naim Suleyman; Acar, Fatih

    2018-04-01

    This paper introduces a novel active snubber cell for soft switching pulse width modulation DC-DC converters. In the proposed converter, the main switch is turned on under zero voltage transition and turned off under zero voltage switching (ZVS). The auxiliary switch is turned on under zero current switching (ZCS) and turned off under zero current transition. The main diode is turned on under ZVS and turned off under ZCS. All of the other semiconductors in the converter are turned on and off with soft switching. There is no extra voltage stress on the semiconductor devices. Besides, the proposed converter has simple structure and ease of control due to common ground. The detailed theoretical analysis of the proposed converter is presented and also verified with both simulation and experimental study at 100 kHz switching frequency and 600 W output power. Furthermore, the efficiency of the proposed converter is 95.7% at nominal power.

  3. Post-tensioning tendon force loss detection using low power pulsed eddy current measurement

    NASA Astrophysics Data System (ADS)

    Kim, Ji-Min; Lee, Jun; Sohn, Hoon

    2018-04-01

    In the field of bridge engineering, pre-fabrication of a bridge member and its construction in site have been issued and studied, which achieves improved quality and rapid construction. For integration of those pre-fabricated segments into a structural member (i.e., a concrete slab, girder and pier), post-tensioning (PT) technique is adopted utilizing a high-strength steel tendon, and an effective investigation of the remaining PT tendon force is essential to assure an overall structural integrity. This study proposes a pulsed eddy current based tendon force loss detection system. A compact eddy current sensor is designed to be installed on the surface of an anchor holding a steel PT tendon. The intensity of the induced eddy current varies with PT tendon force alteration due to the magnetostriction effect of a ferromagnetic material. The advantages of the proposed system are as follows: (1) low power consumption, (2) rapid inspection, and (3) simple installation. Its performance was validated experimentally in a full-scale lab test of a 3.3-m long, 15.2-mm diameter mono-tendon that was tensioned using a universal testing machine. Tendon force was controlled from 20 to 180 kN with 20 kN interval, and eddy current responses were measured and analyzed at each force condition. The proposed damage index and the amount of force loss of PT tendon were monotonically related, and an excessive loss as much as 30 % of an initially-introduced tendon force was successfully predicted.

  4. 75 FR 22577 - Proposed Notice and Comment Policy Version 2.0

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-29

    ... current policy limits EAC's ability to address the rare situations that require swift action. The proposed... Proposed Notice and Comment Policy 2.0. EAC's current Notice and Comment Policy is to provide effective...

  5. Modified current follower-based immittance function simulators

    NASA Astrophysics Data System (ADS)

    Alpaslan, Halil; Yuce, Erkan

    2017-12-01

    In this paper, four immittance function simulators consisting of a single modified current follower with single Z- terminal and a minimum number of passive components are proposed. The first proposed circuit can provide +L parallel with +R and the second proposed one can realise -L parallel with -R. The third proposed structure can provide +L series with +R and the fourth proposed one can realise -L series with -R. However, all the proposed immittance function simulators need a single resistive matching constraint. Parasitic impedance effects on all the proposed immittance function simulators are investigated. A second-order current-mode (CM) high-pass filter derived from the first proposed immittance function simulator is given as an application example. Also, a second-order CM low-pass filter derived from the third proposed immittance function simulator is given as an application example. A number of simulation results based on SPICE programme and an experimental test result are given to verify the theory.

  6. Developing and testing a framework for alternative ownership, tenure and governance strategies for the proposed Detroit-Windsor River crossing : phase I report, February 2009.

    DOT National Transportation Integrated Search

    2009-02-01

    This study focuses on a proposed international crossing across the Detroit River, connecting the cities of Detroit, Michigan and Windsor, Canada, and replacing the current Ambassador Bridge and Detroit-Windsor Tunnel, both built during the late 1920s...

  7. Tangible Multimedia: A Case Study for Bringing Tangibility into Multimedia Learning

    ERIC Educational Resources Information Center

    Tsong, Chau Kien; Chong, Toh Seong; Samsudin, Zarina

    2012-01-01

    Multimedia augmented with tangible objects is an area that has not been explored. Current multimedia systems lack the natural elements that allow young children to learn tangibly and intuitively. In view of this, we propose a research to merge tangible objects with multimedia for preschoolers, and propose to term it as "tangible…

  8. The Emergence of a Novel Representation from Action: Evidence from Preschoolers

    ERIC Educational Resources Information Center

    Boncoddo, Rebecca; Dixon, James A.; Kelley, Elizabeth

    2010-01-01

    Recent work in embodied cognition has proposed that representations and actions are inextricably linked. The current study examines a developmental account of this relationship. Specifically, we propose that children's actions are foundational for novel representations. Thirty-two preschoolers, aged 3.4 to 5.7 years, were asked to solve a set of…

  9. A Proposed Educational Program for Agricultural Development in Iraq.

    ERIC Educational Resources Information Center

    Alsamarrae, Hatam Ali

    The general purpose of this study was to develop an educational program for agricultural development in Iraq, and to identify the best method for its implementation. The proposed program was based primarily upon relevant factors identified through data collection from the following sources: official records, current literature, and the writer's…

  10. Liberal or restricted fluid administration: are we ready for a proposal of a restricted intraoperative approach?

    PubMed

    Della Rocca, Giorgio; Vetrugno, Luigi; Tripi, Gabriella; Deana, Cristian; Barbariol, Federico; Pompei, Livia

    2014-01-01

    Fluid management in the perioperative period has been extensively studied but, despite that, "the right amount" still remains uncertain. The purpose of this paper is to summarize the state of the art of intraoperative fluid approach today. In the current medical literature there are only heterogeneous viewpoints that gives the idea of how confusing the situation is. The approach to the intraoperative fluid management is complex and it should be based on human physiology and the current evidence. An intraoperative restrictive fluid approach in major surgery may be beneficial while Goal-directed Therapy should be superior to the liberal fluid strategy. Finally, we propose a rational approach currently used at our institution.

  11. Dual Transformer Model based on Standard Circuit Elements for the Study of Low- and Mid-frequency Transients

    NASA Astrophysics Data System (ADS)

    Jazebi, Saeed

    This thesis is a step forward toward achieving the final objective of creating a fully dual model for transformers including eddy currents and nonlinearities of the iron core using the fundamental electrical components already available in the EMTP-type programs. The model is effective for the study of the performance of transformers during power system transients. This is very important for transformer designers, because the insulation of transformers is determined with the overvoltages caused by lightning or switching operations. There are also internally induced transients that occur when a switch is actuated. For example switching actions for reconfiguration of distribution systems that offers economic advantages, or protective actions to clear faults and large short-circuit currents. Many of the smart grid concepts currently under development by many utilities rely heavily on switching to optimize resources that produce transients in the system. On the other hand, inrush currents produce mechanical forces which deform transformer windings and cause malfunction of the differential protection. Also, transformer performance under ferroresonance and geomagnetic induced currents are necessary to study. In this thesis, a physically consistent dual model applicable to single-phase two-winding transformers is proposed. First, the topology of a dual electrical equivalent circuit is obtained from the direct application of the principle of duality. Then, the model parameters are computed considering the variations of the transformer electromagnetic behavior under various operating conditions. Current modeling techniques use different topological models to represent diverse transient situations. The reversible model proposed in this thesis unifies the terminal and topological equivalent circuits. The model remains invariable for all low-frequency transients including deep saturation conditions driven from any of the two windings. The very high saturation region of the iron core magnetizing characteristic is modified with the accurate measurement of the air-core inductance. The air-core inductance is measured using a non-ideal low-power rectifier. Its dc output serves to drive the transformer into deep saturation, and its ripple provides low-amplitude variable excitation. The principal advantage of this method is its simplicity. To model the eddy current effects in the windings, a novel equivalent circuit is proposed. The circuit is derived from the principle of duality and therefore, matches the electromagnetic physical behavior of the transformer windings. It properly models the flux paths and current distribution from dc to MHz. The model is synthesized from a non-uniform concentric discretization of the windings. Concise guidelines are given to optimally calculate the width of the sub-divisions for various transient simulations. To compute the circuit parameters only information about the geometry of the windings and about their material properties is needed. The calculation of the circuit parameters does not require an iterative process. Therefore, the parameters are always real, positive, and free from convergence problems. The proposed model is tested with single-phase transformers for the calculation of magnetizing inrush currents, series ferroresonance, and Geomagnetic Induced Currents (GIC). The electromagnetic transient response of the model is compared to laboratory measurements for validation. Also, 3D finite element simulations are used to validate the electromagnetic behavior of the transformer model. Large manufacturer of transformers, power system designers, and electrical utility companies can benefit from the new model. It simplifies the design and optimization of the transformers' insulation, thereby reducing cost, and enhancing reliability of the system. The model could also be used for inrush current and differential protection studies, geomagnetic induced current studies, harmonic penetration studies, and switching transient studies.

  12. Proposed regulations for research with biospecimens: responses from stakeholders at CTSA consortium institutions.

    PubMed

    Botkin, Jeffrey R; Anderson, Rebecca; Murray, Tom; Beskow, Laura M; Maschke, Karen; Cuttler, Leona

    2014-04-01

    Secondary research with biospecimens acquired through clinical care and through research is often conducted without the informed consent of individuals from whom the specimens were acquired. While such uses are consistent with the current federal regulations, surveys of the general public suggest that many individuals would prefer more information and choice regarding research use of biospecimens. The federal government issued an Advance Notice of Proposed Rulemaking (ANPRM) in 2011 that proposed a number of potential changes in the regulations governing human subjects. These proposed regulations are particularly pertinent to institutions committed to research involving human subjects-including institutions in the NIH-funded Clinical and Translational Science Awards (CTSA) consortium. In this study, we reviewed public responses by CTSA-funded institutions and CTSA-affiliated organizations and groups regarding the proposed changes in the ANPRM with respect to research with biospecimens. Our results indicate that the majority of responses to the ANPRM from CTSA institutions were not supportive of the proposed changes. While many responses acknowledge a need to change current research practices regarding biospecimens, the proposed changes in the ANPRM received only limited support from this subgroup of academic research institutions. © 2014 Wiley Periodicals, Inc.

  13. Proposed Regulations for Research with Biospecimens: Responses from Stakeholders at CTSA Consortium Institutions

    PubMed Central

    Botkin, Jeffrey R; Anderson, Rebecca; Murray, Tom; Beskow, Laura M.; Maschke, Karen; Cuttler, Leona

    2014-01-01

    Secondary research with biospecimens acquired through clinical care and through research is often conducted without the informed consent of individuals from whom the specimens were acquired. While such uses are consistent with the current federal regulations, surveys of the general public suggest that many individuals would prefer more information and choice regarding research use of biospecimens. The federal government issued an Advance Notice of Proposed Rulemaking (ANPRM) in 2011 that proposed a number of potential changes in the regulations governing human subjects. These proposed regulations are particularly pertinent to institutions committed to research involving human subjects – including institutions in the NIH-funded Clinical and Translational Science Awards (CTSA) consortium. In this study, we reviewed public responses by CTSA-funded institutions and CTS-affiliated organizations and groups regarding the proposed changes in the ANPRM with respect to research with biospecimens. Our results indicate that the majority of responses to the ANPRM from CTSA institutions were not supportive of the proposed changes. While many responses acknowledge a need to change current research practices regarding biospecimens, the proposed changes in the ANPRM received only limited support from this subgroup of academic research institutions. PMID:24459038

  14. An optimization design proposal of automated guided vehicles for mixed type transportation in hospital environments.

    PubMed

    González, Domingo; Romero, Luis; Espinosa, María Del Mar; Domínguez, Manuel

    2017-01-01

    The aim of this paper is to present an optimization proposal in the automated guided vehicles design used in hospital logistics, as well as to analyze the impact of its implementation in a real environment. This proposal is based on the design of those elements that would allow the vehicles to deliver an extra cart by the towing method. So, the proposal intention is to improve the productivity and the performance of the current vehicles by using a transportation method of combined carts. The study has been developed following concurrent engineering premises from three different viewpoints. First, the sequence of operations has been described, and second, a proposal of design of the equipment has been undertaken. Finally, the impact of the proposal has been analyzed according to real data from the Hospital Universitario Rio Hortega in Valladolid (Spain). In this particular case, by the implementation of the analyzed proposal in the hospital a reduction of over 35% of the current time of use can be achieved. This result may allow adding new tasks to the vehicles, and according to this, both a new kind of vehicle and a specific module can be developed in order to get a better performance.

  15. Stopping electric field extension in a modified nanostructure based on SOI technology - A comprehensive numerical study

    NASA Astrophysics Data System (ADS)

    Anvarifard, Mohammad K.; Orouji, Ali A.

    2017-11-01

    This article has related a particular knowledge in order to reduce short channel effects (SCEs) in nano-devices based on silicon-on-insulator (SOI) MOSFETs. The device under study has been designed in 22 nm node technology with embedding Si3N4 extra oxide as a stopping layer of electric field and a useful heatsink for transferring generated heat. Two important subjects (DC characteristics and RF characteristics) have been investigated, simultaneously. Stopping electric field extension and enhancement of channel thermal conduction are introduced as an entrance gateway for this work so that improve the electrical characteristics, eventually. The inserted extra oxide made by the Si3N4 material has a vital impact on the modification of the electrical and thermal features in the proposed device. An immense comparison between the proposed SOI and conventional SOI showed that the proposed structure has higher electrical and thermal proficiency than the conventional structure in terms of main parameters such as short channel effects (SCEs), leakage current, floating body effect (FBE), self-heating effect (SHE), voltage gain, ratio of On-current to Off- current, transconductance, output conductance, minimum noise figure and power gain.

  16. Small transport aircraft technology. [STAT

    NASA Technical Reports Server (NTRS)

    Galloway, T. L.

    1981-01-01

    The results of contracted studies identifying the potential benefits of advanced technology are presented. Current in house studies and research efforts are discussed. An overview of the proposed technology elements in STAT research is presented.

  17. Assembly Line Efficiency Improvement by Using WITNESS Simulation Software

    NASA Astrophysics Data System (ADS)

    Yasir, A. S. H. M.; Mohamed, N. M. Z. N.

    2018-03-01

    In the nowadays-competitive world, efficiencies and the productivity of the assembly line are essential in manufacturing company. This paper demonstrates the study of the existing production line performance. The actual cycle time observed and recorded during the working process. The current layout was designed and analysed using Witness simulation software. The productivity and effectiveness for every single operator are measured to determine the operator idle time and busy time. Two new alternatives layout were proposed and analysed by using Witness simulation software to improve the performance of production activities. This research provided valuable and better understanding of production effectiveness by adjusting the line balancing. After analysing the data, simulation result from the current layout and the proposed plan later been tabulated to compare the improved efficiency and productivity. The proposed design plan has shown an increase in yield and productivity compared to the current arrangement. This research has been carried out in company XYZ, which is one of the automotive premises in Pahang, Malaysia.

  18. A Wavelet-based Fast Discrimination of Transformer Magnetizing Inrush Current

    NASA Astrophysics Data System (ADS)

    Kitayama, Masashi

    Recently customers who need electricity of higher quality have been installing co-generation facilities. They can avoid voltage sags and other distribution system related disturbances by supplying electricity to important load from their generators. For another example, FRIENDS, highly reliable distribution system using semiconductor switches or storage devices based on power electronics technology, is proposed. These examples illustrates that the request for high reliability in distribution system is increasing. In order to realize these systems, fast relaying algorithms are indispensable. The author proposes a new method of detecting magnetizing inrush current using discrete wavelet transform (DWT). DWT provides the function of detecting discontinuity of current waveform. Inrush current occurs when transformer core becomes saturated. The proposed method detects spikes of DWT components derived from the discontinuity of the current waveform at both the beginning and the end of inrush current. Wavelet thresholding, one of the wavelet-based statistical modeling, was applied to detect the DWT component spikes. The proposed method is verified using experimental data using single-phase transformer and the proposed method is proved to be effective.

  19. Perceptions of young Jordanian adults to proposed anti-tobacco pictorial warning labels

    PubMed Central

    2011-01-01

    Background In commitment to the Framework Convention on Tobacco Control (FCTC), four new pictorial warnings are now being proposed for display on cigarette packages sold in Jordan. The aim of this study was to gauge the immediate perceptions of young Jordanian adults towards these new pictorials and compare these perceptions to those of the pictorial currently being used in the country. Methods A cross-sectional survey was conducted on a convenience sample of youth aged 17-26. The interviewer-administered survey gauged participants' perceptions of salience, fear elicitation, and gained information as well as participants' motivation to remain non-smokers or quit smoking after viewing each of the four proposed new pictorials as well as the current pictorial used in Jordan. Perceptions regarding each new pictorial were compared to the current pictorial. Results A total of 450 surveys were included in the analysis. The sample (mean age 20.9) was 51.6% female and 31.3% cigarette (regular or occasional) smokers. In smokers, only one proposed pictorial had significantly more smokers perceiving it as salient or adding to information when compared to the current pictorial. More smokers reported fear when observing the proposed pictorials compared with current pictorial, but overall proportions reporting fear were generally less than 50%. Furthermore, all new pictorials motivated significantly more smokers to consider quitting compared with the current pictorial; however, the overall proportion of smokers reporting motivation was < 25%. Among nonsmokers, significantly more respondents perceived the new pictorials as salient and fear-eliciting compared to the old pictorial, but there were no major differences in information added. Motivation to remain non-smokers was comparable between the old and new pictorials. Conclusion Given the variability of response across both smokers and nonsmokers, and across the three elements of perception (salience, added information, fear) for each pictorial, further testing of the pictorials in a more diverse sample of Jordanian young adults prior to launch is recommended. PMID:21627794

  20. Why Study Time Does Not Predict Grade Point Average across College Students: Implications of Deliberate Practice for Academic Performance

    ERIC Educational Resources Information Center

    Plant, E. Ashby; Ericsson, K. Anders; Hill, Len; Asberg, Kia

    2005-01-01

    The current work draws upon the theoretical framework of deliberate practice in order to clarify why the amount of study by college students is a poor predictor of academic performance. A model was proposed where performance in college, both cumulatively and for a current semester, was jointly determined by previous knowledge and skills as well as…

  1. 75 FR 70328 - Self-Regulatory Organizations; Fixed Income Clearing Corporation; Notice of Filing of Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... Eliminate Certain Cash Adjustments Currently Processed by the MBSD November 10, 2010. Pursuant to Section 19... Change The purpose of the proposed rule change is to eliminate cash adjustments that are currently... Purpose of, and Statutory Basis for, the Proposed Rule Change FICC is proposing to eliminate the cash...

  2. Study on model current predictive control method of PV grid- connected inverters systems with voltage sag

    NASA Astrophysics Data System (ADS)

    Jin, N.; Yang, F.; Shang, S. Y.; Tao, T.; Liu, J. S.

    2016-08-01

    According to the limitations of the LVRT technology of traditional photovoltaic inverter existed, this paper proposes a low voltage ride through (LVRT) control method based on model current predictive control (MCPC). This method can effectively improve the photovoltaic inverter output characteristics and response speed. The MCPC method of photovoltaic grid-connected inverter designed, the sum of the absolute value of the predictive current and the given current error is adopted as the cost function with the model predictive control method. According to the MCPC, the optimal space voltage vector is selected. Photovoltaic inverter has achieved automatically switches of priority active or reactive power control of two control modes according to the different operating states, which effectively improve the inverter capability of LVRT. The simulation and experimental results proves that the proposed method is correct and effective.

  3. Regression analysis of informative current status data with the additive hazards model.

    PubMed

    Zhao, Shishun; Hu, Tao; Ma, Ling; Wang, Peijie; Sun, Jianguo

    2015-04-01

    This paper discusses regression analysis of current status failure time data arising from the additive hazards model in the presence of informative censoring. Many methods have been developed for regression analysis of current status data under various regression models if the censoring is noninformative, and also there exists a large literature on parametric analysis of informative current status data in the context of tumorgenicity experiments. In this paper, a semiparametric maximum likelihood estimation procedure is presented and in the method, the copula model is employed to describe the relationship between the failure time of interest and the censoring time. Furthermore, I-splines are used to approximate the nonparametric functions involved and the asymptotic consistency and normality of the proposed estimators are established. A simulation study is conducted and indicates that the proposed approach works well for practical situations. An illustrative example is also provided.

  4. Studies of the intermediate and deep circulation in the western equatorial Atlantic

    NASA Technical Reports Server (NTRS)

    Desaubies, Yves; Frankignoul, C.; Merle, Jacques

    1991-01-01

    This proposal concerns the preparation and design of an experiment, the objective of which is to improve our knowledge of the intermediate and deep circulation in the western equatorial Atlantic Ocean. We shall focus on the description of the western boundary currents, of their crossing with the equator, on the estimation of their mass and heat fluxes, and their seasonal and interannual variations. We will use satellite altimetric data, tomographic measurements, and in situ observations (current measurements, hydrology, and floaters). We propose a feasibility study and the definition of a strategy based on a high-resolution Geophysical Fluid Dynamics Laboratory (GFDL) numerical model to define which in situ measurements are necessary to optimally complete the altimetric observations.

  5. Model invariance across genders of the Broad Autism Phenotype Questionnaire.

    PubMed

    Broderick, Neill; Wade, Jordan L; Meyer, J Patrick; Hull, Michael; Reeve, Ronald E

    2015-10-01

    ASD is one of the most heritable neuropsychiatric disorders, though comprehensive genetic liability remains elusive. To facilitate genetic research, researchers employ the concept of the broad autism phenotype (BAP), a milder presentation of traits in undiagnosed relatives. Research suggests that the BAP Questionnaire (BAPQ) demonstrates psychometric properties superior to other self-report measures. To examine evidence regarding validity of the BAPQ, the current study used confirmatory factor analysis to test the assumption of model invariance across genders. Results of the current study upheld model invariance at each level of parameter constraint; however, model fit indices suggested limited goodness-of-fit between the proposed model and the sample. Exploratory analyses investigated alternate factor structure models but ultimately supported the proposed three-factor structure model.

  6. Mind the Gap! Students' Use of Exemplars and Detailed Rubrics as Formative Assessment

    ERIC Educational Resources Information Center

    Lipnevich, Anastasiya A.; McCallen, Leigh N.; Miles, Katharine Pace; Smith, Jeffrey K.

    2014-01-01

    The current study examined efficient modes for providing standardized feedback to improve performance on an assignment for a second year college class involving writing a brief research proposal. Two forms of standardized feedback (detailed rubric and proposal exemplars) were utilized is an experimental design with undergraduate students (N = 100)…

  7. 77 FR 60429 - Natural Currents Energy Services, LLC; Notice of Preliminary Permit Application Accepted for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... Services, LLC filed an application, pursuant to section 4(f) of the Federal Power Act, proposing to study the feasibility of the Fisher's Island Tidal Energy Project, which would be located on the Long Island...' express permission. The proposed project would consist of: (1) Installation of 50 NC Sea Dragon tidal...

  8. Optical Pulsars and Black Arrows: Discoveries as Occasioned Productions

    ERIC Educational Resources Information Center

    Koschmann, Timothy; Zemel, Alan

    2009-01-01

    The current article represents a methodological proposal. It seeks to address the question of how one might recognize a discovery as a discovery without knowing in advance what is available to be discovered. We propose a solution and demonstrate it using data from a study previously reported by J. Roschelle (1992). Roschelle investigated 2…

  9. A microwave field-driven transistor-like skyrmionic device with the microwave current-assisted skyrmion creation

    NASA Astrophysics Data System (ADS)

    Xia, Jing; Huang, Yangqi; Zhang, Xichao; Kang, Wang; Zheng, Chentian; Liu, Xiaoxi; Zhao, Weisheng; Zhou, Yan

    2017-10-01

    Magnetic skyrmion is a topologically protected domain-wall structure at nanoscale, which could serve as a basic building block for advanced spintronic devices. Here, we propose a microwave field-driven skyrmionic device with the transistor-like function, where the motion of a skyrmion in a voltage-gated ferromagnetic nanotrack is studied by micromagnetic simulations. It is demonstrated that the microwave field can drive the motion of a skyrmion by exciting the propagating spin waves, and the skyrmion motion can be governed by a gate voltage. We also investigate the microwave current-assisted creation of a skyrmion to facilitate the operation of the transistor-like skyrmionic device on the source terminal. It is found that the microwave current with an appropriate frequency can reduce the threshold current density required for the creation of a skyrmion from the ferromagnetic background. The proposed transistor-like skyrmionic device operated with the microwave field and current could be useful for building future skyrmion-based circuits.

  10. Kentucky pharmacists' opinions of the potential reclassification of pseudoephedrine as a legend drug

    PubMed Central

    Monson, Kathleen E.; Freeman, Patricia R.; Goodin, Amie J.; Talbert, Jeffery; Blumenschein, Karen

    2015-01-01

    Objectives To collect and analyze Kentucky pharmacists' opinions of the effectiveness of current methamphetamine precursor controls, to analyze proposed legislation to make pseudoephedrine (PSE) a legend drug, and to analyze the potential impact of such legislation on pharmacy practice and patients. Design Descriptive, nonexperimental survey study. Setting Kentucky; June through October 2012. Participants 431 Kentucky community pharmacists. Intervention Mailed survey. Main outcome measures Perceived efficacy of current methamphetamine precursor controls, anticipated impact on individual pharmacy practices and patients of proposed legislation to make PSE available by prescription only, and current opinions about the proposed legislation. Results Analysis of 431 community pharmacists showed that approximately 77% believed proposed legislation to make PSE available by prescription only would be effective in reducing methamphetamine abuse and methamphetamine-related laboratory incidents, with 56.2% indicating support for the proposed legislation. Pharmacists practicing in chain pharmacies were 2.9 times more likely to support the legislation than pharmacists practicing in independent pharmacies. Additional factors influencing pharmacist support included Kentucky region of practice, anticipated impact on time spent on PSE activities, pharmacy profit, methamphetamine abuse, and methamphetamine-related laboratory incidents. Pharmacists practicing in regions of Kentucky associated with higher methamphetamine abuse appear to more strongly support the proposed legislation. Conclusion Pharmacists are at the frontline of PSE distribution. Gaining a better understanding of issues surrounding the distribution of PSE will enhance the likelihood that future legislation may be crafted to reduce methamphetamine production, laboratory incidents, and abuse while minimizing inconvenience and cost. PMID:25063261

  11. Kentucky pharmacists' opinions of the potential reclassification of pseudoephedrine as a legend drug.

    PubMed

    Monson, Kathleen E; Freeman, Patricia R; Goodin, Amie J; Talbert, Jeffery; Blumenschein, Karen

    2014-01-01

    To collect and analyze Kentucky pharmacists' opinions of the effectiveness of current methamphetamine precursor controls, to analyze proposed legislation to make pseudoephedrine (PSE) a legend drug, and to analyze the potential impact of such legislation on pharmacy practice and patients. Descriptive, nonexperimental survey study. Kentucky; June through October 2012. 431 Kentucky community pharmacists. Mailed survey. Perceived efficacy of current methamphetamine precursor controls, anticipated impact on individual pharmacy practices and patients of proposed legislation to make PSE available by prescription only, and current opinions about the proposed legislation. Analysis of 431 community pharmacists showed that approximately 77% believed proposed legislation to make PSE available by prescription only would be effective in reducing methamphetamine abuse and methamphetamine-related laboratory incidents, with 56.2% indicating support for the proposed legislation. Pharmacists practicing in chain pharmacies were 2.9 times more likely to support the legislation than pharmacists practicing in independent pharmacies. Additional factors influencing pharmacist support included Kentucky region of practice, anticipated impact on time spent on PSE activities, pharmacy profit, methamphetamine abuse, and methamphetamine-related laboratory incidents. Pharmacists practicing in regions of Kentucky associated with higher methamphetamine abuse appear to more strongly support the proposed legislation. Pharmacists are at the frontline of PSE distribution. Gaining a better understanding of issues surrounding the distribution of PSE will enhance the likelihood that future legislation may be crafted to reduce methamphetamine production, laboratory incidents, and abuse while minimizing inconvenience and cost.

  12. Modeling of Waves, Hydrodynamics and Sediment Transport for Protection of Wetlands at Braddock Bay, New York

    DTIC Science & Technology

    2015-03-01

    entrance were evaluated on their ability to reduce potential impacts of waves and currents on wet- lands. Study results indicated all three proposed...transport de- veloped were used in the evaluation of proposed solutions. The prelimi- nary modeling results helped to assess general sediment pattern...Corps of Engineers (USACE), Buffalo Dis- trict, is conducting a study to evaluate shoreline protection measures for coastal wetlands at Braddock Bay

  13. A new wavelet transform to sparsely represent cortical current densities for EEG/MEG inverse problems.

    PubMed

    Liao, Ke; Zhu, Min; Ding, Lei

    2013-08-01

    The present study investigated the use of transform sparseness of cortical current density on human brain surface to improve electroencephalography/magnetoencephalography (EEG/MEG) inverse solutions. Transform sparseness was assessed by evaluating compressibility of cortical current densities in transform domains. To do that, a structure compression method from computer graphics was first adopted to compress cortical surface structure, either regular or irregular, into hierarchical multi-resolution meshes. Then, a new face-based wavelet method based on generated multi-resolution meshes was proposed to compress current density functions defined on cortical surfaces. Twelve cortical surface models were built by three EEG/MEG softwares and their structural compressibility was evaluated and compared by the proposed method. Monte Carlo simulations were implemented to evaluate the performance of the proposed wavelet method in compressing various cortical current density distributions as compared to other two available vertex-based wavelet methods. The present results indicate that the face-based wavelet method can achieve higher transform sparseness than vertex-based wavelet methods. Furthermore, basis functions from the face-based wavelet method have lower coherence against typical EEG and MEG measurement systems than vertex-based wavelet methods. Both high transform sparseness and low coherent measurements suggest that the proposed face-based wavelet method can improve the performance of L1-norm regularized EEG/MEG inverse solutions, which was further demonstrated in simulations and experimental setups using MEG data. Thus, this new transform on complicated cortical structure is promising to significantly advance EEG/MEG inverse source imaging technologies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Nonlinear spin current generation in noncentrosymmetric spin-orbit coupled systems

    NASA Astrophysics Data System (ADS)

    Hamamoto, Keita; Ezawa, Motohiko; Kim, Kun Woo; Morimoto, Takahiro; Nagaosa, Naoto

    2017-06-01

    Spin current plays a central role in spintronics. In particular, finding more efficient ways to generate spin current has been an important issue and has been studied actively. For example, representative methods of spin-current generation include spin-polarized current injections from ferromagnetic metals, the spin Hall effect, and the spin battery. Here, we theoretically propose a mechanism of spin-current generation based on nonlinear phenomena. By using Boltzmann transport theory, we show that a simple application of the electric field E induces spin current proportional to E2 in noncentrosymmetric spin-orbit coupled systems. We demonstrate that the nonlinear spin current of the proposed mechanism is supported in the surface state of three-dimensional topological insulators and two-dimensional semiconductors with the Rashba and/or Dresselhaus interaction. In the latter case, the angular dependence of the nonlinear spin current can be manipulated by the direction of the electric field and by the ratio of the Rashba and Dresselhaus interactions. We find that the magnitude of the spin current largely exceeds those in the previous methods for a reasonable magnitude of the electric field. Furthermore, we show that application of ac electric fields (e.g., terahertz light) leads to the rectifying effect of the spin current, where dc spin current is generated. These findings will pave a route to manipulate the spin current in noncentrosymmetric crystals.

  15. Estimating effect of environmental contaminants on women's subfecundity for the MoBa study data with an outcome-dependent sampling scheme

    PubMed Central

    Ding, Jieli; Zhou, Haibo; Liu, Yanyan; Cai, Jianwen; Longnecker, Matthew P.

    2014-01-01

    Motivated by the need from our on-going environmental study in the Norwegian Mother and Child Cohort (MoBa) study, we consider an outcome-dependent sampling (ODS) scheme for failure-time data with censoring. Like the case-cohort design, the ODS design enriches the observed sample by selectively including certain failure subjects. We present an estimated maximum semiparametric empirical likelihood estimation (EMSELE) under the proportional hazards model framework. The asymptotic properties of the proposed estimator were derived. Simulation studies were conducted to evaluate the small-sample performance of our proposed method. Our analyses show that the proposed estimator and design is more efficient than the current default approach and other competing approaches. Applying the proposed approach with the data set from the MoBa study, we found a significant effect of an environmental contaminant on fecundability. PMID:24812419

  16. Digital control of a direct current converter for a hybrid vehicle

    NASA Astrophysics Data System (ADS)

    Hernandez, Juan Manuel

    The nonlinear feedback loops permitting the large signal control of pulse width modulators in direct current converters are discussed. A digital feedback loop on a converter controlling the coupling of a direct current machine is described. It is used in the propulsion of a hybrid vehicle (thermal-electric) with regenerative braking. The protection of the power switches is also studied. An active protection of the MOST bipolar transistor association is proposed.

  17. Case Study: Applying the Theory of Planned Behavior as Interventions to Increase Sponsored Project Proposal Submissions from Liberal Arts Faculty

    ERIC Educational Resources Information Center

    Hartmann, Anita

    2011-01-01

    In the current economic climate, many colleges and universities face similar challenges: the need to increase external sponsorship for research activities and the need to benefit from additional indirect cost recovery. Preparing funding proposals for submission to sponsors is a faculty behavior that can be modified by applying behavioral theory to…

  18. An optimization design proposal of automated guided vehicles for mixed type transportation in hospital environments

    PubMed Central

    González, Domingo; Espinosa, María del Mar; Domínguez, Manuel

    2017-01-01

    Aim The aim of this paper is to present an optimization proposal in the automated guided vehicles design used in hospital logistics, as well as to analyze the impact of its implementation in a real environment. Method This proposal is based on the design of those elements that would allow the vehicles to deliver an extra cart by the towing method. So, the proposal intention is to improve the productivity and the performance of the current vehicles by using a transportation method of combined carts. Results The study has been developed following concurrent engineering premises from three different viewpoints. First, the sequence of operations has been described, and second, a proposal of design of the equipment has been undertaken. Finally, the impact of the proposal has been analyzed according to real data from the Hospital Universitario Rio Hortega in Valladolid (Spain). In this particular case, by the implementation of the analyzed proposal in the hospital a reduction of over 35% of the current time of use can be achieved. This result may allow adding new tasks to the vehicles, and according to this, both a new kind of vehicle and a specific module can be developed in order to get a better performance. PMID:28562681

  19. A Proposal of the European Association for the Study of Obesity to Improve the ICD-11 Diagnostic Criteria for Obesity Based on the Three Dimensions Etiology, Degree of Adiposity and Health Risk

    PubMed Central

    Hebebrand, Johannes; Holm, Jens-Christian; Woodward, Euan; Baker, Jennifer Lyn; Blaak, Ellen; Schutz, Dominique Durrer; Farpour-Lambert, Nathalie J.; Frühbeck, Gema; Halford, Jason G.C.; Lissner, Lauren; Micic, Dragan; Mullerova, Dana; Roman, Gabriela; Schindler, Karin; Toplak, Hermann; Visscher, Tommy L.S.; Yumuk, Volkan

    2017-01-01

    Diagnostic criteria for complex medical conditions caused by a multitude of both genetic and environmental factors should be descriptive and avoid any attribution of causality. Furthermore, the wording used to describe a disorder should be evidence-based and avoid stigmatization of the affected individuals. Both terminology and categorizations should be readily comprehensible for healthcare professionals and guide clinical decision making. Uncertainties with respect to diagnostic issues and their implications may be addressed to direct future clinical research. In this context, the European Association of the Study of Obesity (EASO) considers it an important endeavor to review the current ICD-11 Beta Draft for the definition of overweight and obesity and to propose a substantial revision. We aim to provide an overview of the key issues that we deem relevant for the discussion of the diagnostic criteria. We first discuss the current ICD-10 criteria and those proposed in the ICD 11 Beta Draft. We conclude with our own proposal for diagnostic criteria, which we believe will improve the assessment of patients with obesity in a clinically meaningful way. PMID:28738325

  20. Metering error quantification under voltage and current waveform distortion

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Wang, Jia; Xie, Zhi; Zhang, Ran

    2017-09-01

    With integration of more and more renewable energies and distortion loads into power grid, the voltage and current waveform distortion results in metering error in the smart meters. Because of the negative effects on the metering accuracy and fairness, it is an important subject to study energy metering combined error. In this paper, after the comparing between metering theoretical value and real recorded value under different meter modes for linear and nonlinear loads, a quantification method of metering mode error is proposed under waveform distortion. Based on the metering and time-division multiplier principles, a quantification method of metering accuracy error is proposed also. Analyzing the mode error and accuracy error, a comprehensive error analysis method is presented which is suitable for new energy and nonlinear loads. The proposed method has been proved by simulation.

  1. Betavoltaic Battery Conversion Efficiency Improvement Based on Interlayer Structures

    NASA Astrophysics Data System (ADS)

    Li, Da-Rang; Jiang, Lan; Yin, Jian-Hua; Tan, Yuan-Yuan; Lin, Nai

    2012-07-01

    Significant differences among the doping densities of PN junctions in semiconductors cause lattice mismatch and lattice defects that increase the recombination current of betavoltaic batteries. This extensively decreases the open circuit voltage and the short current, which results in low conversion efficiency. This study proposes P+PINN+-structure based betavoltaic batteries by adding an interlayer to typical PIN structures to improve conversion efficiency. Numerical simulations are conducted for the energy deposition of beta particles along the thickness direction in semiconductors. Based on this, 63Ni-radiation GaAs batteries with PIN and P+PINN+ structures are designed and fabricated to experimentally verify the proposed design. It turns out that the conversion efficiency of the betavoltaic battery with the proposed P+PINN+ structure is about 1.45 times higher than that with the traditional PIN structure.

  2. A simulated annealing approach for redesigning a warehouse network problem

    NASA Astrophysics Data System (ADS)

    Khairuddin, Rozieana; Marlizawati Zainuddin, Zaitul; Jiun, Gan Jia

    2017-09-01

    Now a day, several companies consider downsizing their distribution networks in ways that involve consolidation or phase-out of some of their current warehousing facilities due to the increasing competition, mounting cost pressure and taking advantage on the economies of scale. Consequently, the changes on economic situation after a certain period of time require an adjustment on the network model in order to get the optimal cost under the current economic conditions. This paper aimed to develop a mixed-integer linear programming model for a two-echelon warehouse network redesign problem with capacitated plant and uncapacitated warehouses. The main contribution of this study is considering capacity constraint for existing warehouses. A Simulated Annealing algorithm is proposed to tackle with the proposed model. The numerical solution showed the model and method of solution proposed was practical.

  3. 77 FR 11594 - Agency Information Collection Activities: Proposed Collection; Renewal of Currently Approved...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-27

    ... CONFLICT RESOLUTION Agency Information Collection Activities: Proposed Collection; Renewal of Currently....S. Institute for Environmental Conflict Resolution. ACTION: Notice. SUMMARY: In compliance with the... Environmental Conflict Resolution (the U.S. Institute), part of the Udall Foundation, will submit for Office of...

  4. Magnetic flux amplification by Lenz lenses.

    PubMed

    Schoenmaker, J; Pirota, K R; Teixeira, J C

    2013-08-01

    Tailoring magnetic flux distribution is highly desirable in a wide range of applications such as magnetic sensors and biomedicine. In this paper we study the manipulation of induced currents in passive devices in order to engineer the distribution of magnetic flux intensity in a given region. We propose two different approaches, one based on especially designed wire loops (Lenz law) and the other based on solid conductive pieces (eddy currents). The gain of such devices is mainly determined by geometry giving perspective of high amplification. We consistently modeled, simulated, and executed the proposed devices. Doubled magnetic flux intensity is demonstrated experimentally for a moderate aspect ratio.

  5. Magnetic flux amplification by Lenz lenses

    NASA Astrophysics Data System (ADS)

    Schoenmaker, J.; Pirota, K. R.; Teixeira, J. C.

    2013-08-01

    Tailoring magnetic flux distribution is highly desirable in a wide range of applications such as magnetic sensors and biomedicine. In this paper we study the manipulation of induced currents in passive devices in order to engineer the distribution of magnetic flux intensity in a given region. We propose two different approaches, one based on especially designed wire loops (Lenz law) and the other based on solid conductive pieces (eddy currents). The gain of such devices is mainly determined by geometry giving perspective of high amplification. We consistently modeled, simulated, and executed the proposed devices. Doubled magnetic flux intensity is demonstrated experimentally for a moderate aspect ratio.

  6. Microdose Induced Drain Leakage Effects in Power Trench MOSFETs: Experiment and Modeling

    NASA Astrophysics Data System (ADS)

    Zebrev, Gennady I.; Vatuev, Alexander S.; Useinov, Rustem G.; Emeliyanov, Vladimir V.; Anashin, Vasily S.; Gorbunov, Maxim S.; Turin, Valentin O.; Yesenkov, Kirill A.

    2014-08-01

    We study experimentally and theoretically the micro-dose induced drain-source leakage current in the trench power MOSFETs under irradiation with high-LET heavy ions. We found experimentally that cumulative increase of leakage current occurs by means of stochastic spikes corresponding to a strike of single heavy ion into the MOSFET gate oxide. We simulate this effect with the proposed analytic model allowing to describe (including Monte Carlo methods) both the deterministic (cumulative dose) and stochastic (single event) aspects of the problem. Based on this model the survival probability assessment in space heavy ion environment with high LETs was proposed.

  7. Design and control of the phase current of a brushless dc motor to eliminate cogging torque

    NASA Astrophysics Data System (ADS)

    Jang, G. H.; Lee, C. J.

    2006-04-01

    This paper presents a design and control method of the phase current to reduce the torque ripple of a brushless dc (BLDC) motor by eliminating cogging torque. The cogging torque is the main source of torque ripple and consequently of speed error, and it is also the excitation source to generate the vibration and noise of a motor. This research proposes a modified current wave form, which is composed of main and auxiliary currents. The former is the conventional current to generate the commutating torque. The latter generates the torque with the same magnitude and opposite sign of the corresponding cogging torque at the given position in order to eliminate the cogging torque. Time-stepping finite element method simulation considering pulse-width-modulation switching method has been performed to verify the effectiveness of the proposed method, and it shows that this proposed method reduces torque ripple by 36%. A digital-signal-processor-based controller is also developed to implement the proposed method, and it shows that this proposed method reduces the speed ripple significantly.

  8. 75 FR 66081 - Natural Currents Energy Services, LLC; Notice of Preliminary Permit Application Accepted for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-27

    ... the Federal Power Act, proposing to study the feasibility of the Killisnoo Tidal Energy Project... generation of 1,000 megawatt-hours. Applicant Contact: Roger Bason, President, Natural Currents Energy... Support. Kimberly D. Bose, Secretary. [FR Doc. 2010-27127 Filed 10-26-10; 8:45 am] BILLING CODE 6717-01-P ...

  9. Please Touch the Children: Appropriate Touch in the Primary Classroom

    ERIC Educational Resources Information Center

    Owen, Pamela M.; Gillentine, Jonathan

    2011-01-01

    This study proposes to shift the current theoretical framework in which teachers practise a guarded approach regarding the touching of children in early childhood settings, towards a practice of acceptance. A brief historical context of touching is presented and supplemented with a survey of 63 currently practising K-3rd grade teachers. The survey…

  10. Toward a Theory-Based Natural Language Capability in Robots and Other Embodied Agents: Evaluating Hausser's SLIM Theory and Database Semantics

    ERIC Educational Resources Information Center

    Burk, Robin K.

    2010-01-01

    Computational natural language understanding and generation have been a goal of artificial intelligence since McCarthy, Minsky, Rochester and Shannon first proposed to spend the summer of 1956 studying this and related problems. Although statistical approaches dominate current natural language applications, two current research trends bring…

  11. M Current-Based Therapies for Nerve Agent Seizures

    DTIC Science & Technology

    2013-07-01

    Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS Seizures, status epilepticus Cholinergic, M Current...Channel openers in cholinergic overstimulation-induced status epilepticus . Body: We proposed to study the effects of organophosphates and muscarinic...test whether drugs that open M channels would terminate status epilepticus induced by an organophosphate and cholinergic agonist (Li/Pilocarpine). Two

  12. Rethinking High School Principal Compensation Practices: An Analysis of Salaries in South Carolina and Theoretical Models

    ERIC Educational Resources Information Center

    Newman, Tim A.

    2012-01-01

    This study described the current state of principal salaries in South Carolina and compared the salaries of similar size schools by specific report card performance and demographic variables. Based on the findings, theoretical models were proposed, and comparisons were made with current salary data. School boards, human resource personnel and…

  13. A theoretical approach to study the optical sensitivity of a MESFET

    NASA Astrophysics Data System (ADS)

    Dutta, Sutanu

    2018-05-01

    A theoretical model to study the optical sensitivity of a metal-semiconductor field effect transistor has been proposed for a relatively high drain field. An analytical expression of drain current of the device has been derived for a MESFET under optical illumination considering field dependent mobility of electrons across the channel. The variation of drain current with and without optical illumination has been studied with drain and gate voltages. The optical sensitivity of the drain current has been studied for different biasing conditions and gate lengths. In addition, the shift in threshold voltage of a MESFET under optical illumination is determined and optical sensitivity of the device in terms of its threshold voltage has been studied.

  14. Comprehensive Study of Intercity Bus Service in Nebraska

    DOT National Transportation Integrated Search

    1988-03-01

    This study is prompted by the proposed abandonment of regular-route intercity : bus service across northern Nebraska. The current route, which is operated by : Black Hills Stage Lines, provides service from Omaha through Norfolk and Chadron : to Rapi...

  15. Anisotropic thermoelectric behavior in armchair and zigzag mono- and fewlayer MoS2 in thermoelectric generator applications

    PubMed Central

    Arab, Abbas; Li, Qiliang

    2015-01-01

    In this work, we have studied thermoelectric properties of monolayer and fewlayer MoS2 in both armchair and zigzag orientations. Density functional theory (DFT) using non-equilibrium Green’s function (NEGF) method has been implemented to calculate the transmission spectra of mono- and fewlayer MoS2 in armchair and zigzag directions. Phonon transmission spectra are calculated based on parameterization of Stillinger-Weber potential. Thermoelectric figure of merit, ZT, is calculated using these electronic and phonon transmission spectra. In general, a thermoelectric generator is composed of thermocouples made of both n-type and p-type legs. Based on our calculations, monolayer MoS2 in armchair orientation is found to have the highest ZT value for both p-type and n-type legs compared to all other armchair and zigzag structures. We have proposed a thermoelectric generator based on monolayer MoS2 in armchair orientation. Moreover, we have studied the effect of various dopant species on thermoelectric current of our proposed generator. Further, we have compared output current of our proposed generator with those of Silicon thin films. Results indicate that thermoelectric current of MoS2 armchair monolayer is several orders of magnitude higher than that of Silicon thin films. PMID:26333948

  16. Anisotropic thermoelectric behavior in armchair and zigzag mono- and fewlayer MoS2 in thermoelectric generator applications.

    PubMed

    Arab, Abbas; Li, Qiliang

    2015-09-03

    In this work, we have studied thermoelectric properties of monolayer and fewlayer MoS2 in both armchair and zigzag orientations. Density functional theory (DFT) using non-equilibrium Green's function (NEGF) method has been implemented to calculate the transmission spectra of mono- and fewlayer MoS2 in armchair and zigzag directions. Phonon transmission spectra are calculated based on parameterization of Stillinger-Weber potential. Thermoelectric figure of merit, ZT, is calculated using these electronic and phonon transmission spectra. In general, a thermoelectric generator is composed of thermocouples made of both n-type and p-type legs. Based on our calculations, monolayer MoS2 in armchair orientation is found to have the highest ZT value for both p-type and n-type legs compared to all other armchair and zigzag structures. We have proposed a thermoelectric generator based on monolayer MoS2 in armchair orientation. Moreover, we have studied the effect of various dopant species on thermoelectric current of our proposed generator. Further, we have compared output current of our proposed generator with those of Silicon thin films. Results indicate that thermoelectric current of MoS2 armchair monolayer is several orders of magnitude higher than that of Silicon thin films.

  17. An investigation of environmental factors associated with the current and proposed jetty systems at Belle Pass, Louisiana

    NASA Technical Reports Server (NTRS)

    Dantin, E. J.; Whitehurst, C. A.; Durbin, W. T.

    1974-01-01

    The history of the existing jetty system at Belle Pass was investigated to determine its past effect on the littoral currents and beach erosion. Present flow patterns and erosion rates were also studied, along with the prevailing recession rates of local beaches not influenced by the jetty system. Aerial photographs and maps were used in conjunction with periodic hydraulic measurements, ground observations, and physical measurements of beach erosion. A scale model was constructed to further the study of flow patterns and velocities. It is shown that the existing jetty has not adversely affected the coastline in the area; erosive processes have been retarded by the jetty and its companion groin. Future erosion patterns are predicted, and projected effects of the proposed jetty system are given.

  18. Constraints on the pre-impact orbits of Solar system giant impactors

    NASA Astrophysics Data System (ADS)

    Jackson, Alan P.; Gabriel, Travis S. J.; Asphaug, Erik I.

    2018-03-01

    We provide a fast method for computing constraints on impactor pre-impact orbits, applying this to the late giant impacts in the Solar system. These constraints can be used to make quick, broad comparisons of different collision scenarios, identifying some immediately as low-probability events, and narrowing the parameter space in which to target follow-up studies with expensive N-body simulations. We benchmark our parameter space predictions, finding good agreement with existing N-body studies for the Moon. We suggest that high-velocity impact scenarios in the inner Solar system, including all currently proposed single impact scenarios for the formation of Mercury, should be disfavoured. This leaves a multiple hit-and-run scenario as the most probable currently proposed for the formation of Mercury.

  19. Increased Energy Delivery for Parallel Battery Packs with No Regulated Bus

    NASA Astrophysics Data System (ADS)

    Hsu, Chung-Ti

    In this dissertation, a new approach to paralleling different battery types is presented. A method for controlling charging/discharging of different battery packs by using low-cost bi-directional switches instead of DC-DC converters is proposed. The proposed system architecture, algorithms, and control techniques allow batteries with different chemistry, voltage, and SOC to be properly charged and discharged in parallel without causing safety problems. The physical design and cost for the energy management system is substantially reduced. Additionally, specific types of failures in the maximum power point tracking (MPPT) in a photovoltaic (PV) system when tracking only the load current of a DC-DC converter are analyzed. The periodic nonlinear load current will lead MPPT realized by the conventional perturb and observe (P&O) algorithm to be problematic. A modified MPPT algorithm is proposed and it still only requires typically measured signals, yet is suitable for both linear and periodic nonlinear loads. Moreover, for a modular DC-DC converter using several converters in parallel, the input power from PV panels is processed and distributed at the module level. Methods for properly implementing distributed MPPT are studied. A new approach to efficient MPPT under partial shading conditions is presented. The power stage architecture achieves fast input current change rate by combining a current-adjustable converter with a few converters operating at a constant current.

  20. Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 2: application to experimental IV measurements and comparison with other methods

    NASA Astrophysics Data System (ADS)

    Rangel-Kuoppa, Victor-Tapio; Albor-Aguilera, María-de-Lourdes; Hérnandez-Vásquez, César; Flores-Márquez, José-Manuel; Jiménez-Olarte, Daniel; Sastré-Hernández, Jorge; González-Trujillo, Miguel-Ángel; Contreras-Puente, Gerardo-Silverio

    2018-04-01

    In this Part 2 of this series of articles, the procedure proposed in Part 1, namely a new parameter extraction technique of the shunt resistance (R sh ) and saturation current (I sat ) of a current-voltage (I-V) measurement of a solar cell, within the one-diode model, is applied to CdS-CdTe and CIGS-CdS solar cells. First, the Cheung method is used to obtain the series resistance (R s ) and the ideality factor n. Afterwards, procedures A and B proposed in Part 1 are used to obtain R sh and I sat . The procedure is compared with two other commonly used procedures. Better accuracy on the simulated I-V curves used with the parameters extracted by our method is obtained. Also, the integral percentage errors from the simulated I-V curves using the method proposed in this study are one order of magnitude smaller compared with the integral percentage errors using the other two methods.

  1. Comparison of predicted engine core noise with current and proposed aircraft noise certification requirements

    NASA Technical Reports Server (NTRS)

    Vonglahn, U. H.; Groesbeck, D. E.

    1981-01-01

    Predicted engine core noise levels are compared with measured total aircraft noise levels and with current and proposed federal noise certification requirements. Comparisons are made at the FAR-36 measuring stations and include consideration of both full- and cutback-power operation at takeoff. In general, core noise provides a barrier to achieving proposed EPA stage 5 noise levels for all types of aircraft. More specifically, core noise levels will limit further reductions in aircraft noise levels for current widebody commercial aircraft.

  2. Load-Dependent Soft-Switching Method of Half-Bridge Current Doubler for High-Voltage Point-of-Load Converter in Data Center Power Supplies

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

    Cui, Yutian; Yang, Fei; Tolbert, Leon M.

    With the increased cloud computing and digital information storage, the energy requirement of data centers keeps increasing. A high-voltage point of load (HV POL) with an input series output parallel structure is proposed to convert 400 to 1 VDC within a single stage to increase the power conversion efficiency. The symmetrical controlled half-bridge current doubler is selected as the converter topology in the HV POL. A load-dependent soft-switching method has been proposed with an auxiliary circuit that includes inductor, diode, and MOSFETs so that the hard-switching issue of typical symmetrical controlled half-bridge converters is resolved. The operation principles of themore » proposed soft-switching half-bridge current doubler have been analyzed in detail. Then, the necessity of adjusting the timing with the loading in the proposed method is analyzed based on losses, and a controller is designed to realize the load-dependent operation. A lossless RCD current sensing method is used to sense the output inductor current value in the proposed load-dependent operation. In conclusion, experimental efficiency of a hardware prototype is provided to show that the proposed method can increase the converter's efficiency in both heavy- and light-load conditions.« less

  3. Load-Dependent Soft-Switching Method of Half-Bridge Current Doubler for High-Voltage Point-of-Load Converter in Data Center Power Supplies

    DOE PAGES

    Cui, Yutian; Yang, Fei; Tolbert, Leon M.; ...

    2016-06-14

    With the increased cloud computing and digital information storage, the energy requirement of data centers keeps increasing. A high-voltage point of load (HV POL) with an input series output parallel structure is proposed to convert 400 to 1 VDC within a single stage to increase the power conversion efficiency. The symmetrical controlled half-bridge current doubler is selected as the converter topology in the HV POL. A load-dependent soft-switching method has been proposed with an auxiliary circuit that includes inductor, diode, and MOSFETs so that the hard-switching issue of typical symmetrical controlled half-bridge converters is resolved. The operation principles of themore » proposed soft-switching half-bridge current doubler have been analyzed in detail. Then, the necessity of adjusting the timing with the loading in the proposed method is analyzed based on losses, and a controller is designed to realize the load-dependent operation. A lossless RCD current sensing method is used to sense the output inductor current value in the proposed load-dependent operation. In conclusion, experimental efficiency of a hardware prototype is provided to show that the proposed method can increase the converter's efficiency in both heavy- and light-load conditions.« less

  4. Underwater acoustic wireless sensor networks: advances and future trends in physical, MAC and routing layers.

    PubMed

    Climent, Salvador; Sanchez, Antonio; Capella, Juan Vicente; Meratnia, Nirvana; Serrano, Juan Jose

    2014-01-06

    This survey aims to provide a comprehensive overview of the current research on underwater wireless sensor networks, focusing on the lower layers of the communication stack, and envisions future trends and challenges. It analyzes the current state-of-the-art on the physical, medium access control and routing layers. It summarizes their security threads and surveys the currently proposed studies. Current envisioned niches for further advances in underwater networks research range from efficient, low-power algorithms and modulations to intelligent, energy-aware routing and medium access control protocols.

  5. Study on the steady operating state of a micro-pulse electron gun.

    PubMed

    Kui, Zhou; Xiangyang, Lu; Shengwen, Quan; Jifei, Zhao; Xing, Luo; Ziqin, Yang

    2014-09-01

    Micro-pulse electron gun (MPG) employs the basic concept of multipacting to produce high-current and short-pulse electron beams from a radio-frequency (RF) cavity. The concept of MPG has been proposed for more than two decades. However, the unstable operating state of MPG vastly obstructs its practical applications. This paper presents a study on the steady operating state of a micro-pulse electron gun with theory and experiments. The requirements for the steady operating state are proposed through the analysis of the interaction between the RF cavity and the beam load. Accordingly, a MPG cavity with the frequency of 2856 MHz has been designed, constructed, and tested. Some primary experiments have been finished. Both the unstable and stable operating states of the MPG have been observed. The stable output beam current has been detected at about 3.8 mA. Further experimental study is under way now.

  6. 75 FR 70730 - Natural Currents Energy Services, LLC; Notice of Preliminary Permit Application Accepted for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-18

    ...(f) of the Federal Power Act, proposing to study the feasibility of the Salem Tidal Energy Project... Atlantic Port Terminal to the south. The project proposes between 10 and 30 NC Sea Dragon or Red Hawk tidal... minimum of 3,504,000 kW hours per year with the installation of 10 units. Applicant Contact: Mr. Roger...

  7. Current-induced dissipation in spectral wave models

    NASA Astrophysics Data System (ADS)

    Rapizo, H.; Babanin, A. V.; Provis, D.; Rogers, W. E.

    2017-03-01

    Despite many recent developments of the parameterization for wave dissipation in spectral models, it is evident that when waves propagate onto strong adverse currents the rate of energy dissipation is not properly estimated. The issue of current-induced dissipation is studied through a comprehensive data set in the tidal inlet of Port Phillip Heads, Australia. The wave parameters analyzed are significantly modulated by the tidal currents. Wave height in conditions of opposing currents (ebb tide) can reach twice the offshore value, whereas during coflowing currents (flood), it can be reduced to half. The wind-wave model SWAN is able to reproduce the tide-induced modulation of waves and the results show that the variation of currents is the dominant factor in modifying the wave field. In stationary simulations, the model provides an accurate representation of wave height for slack and flood tides. During ebb tides, wave energy is highly overestimated over the opposing current jet. None of the four parameterizations for wave dissipation tested performs satisfactorily. A modification to enhance dissipation as a function of the local currents is proposed. It consists of the addition of a factor that represents current-induced wave steepening and it is scaled by the ratio of spectral energy to the threshold breaking level. The new term asymptotes to the original form as the current in the wave direction tends to zero. The proposed modification considerably improves wave height and mean period in conditions of adverse currents, whereas the good model performance in coflowing currents is unaltered.

  8. Writing a Research Proposal to The Research Council of Oman.

    PubMed

    Al-Shukaili, Ahmed; Al-Maniri, Abdullah

    2017-05-01

    Writing a research proposal can be a challenging task for young researchers. This article explains how to write a strong research proposal to apply for funding, specifically, a proposal for The Research Council (TRC) of Oman. Three different research proposal application forms are currently used in TRC, including Open Research Grant (ORG), Graduate Research Support Program (GRSP), and Faculty-mentored Undergraduate Research Award Program (FURAP). The application forms are filled and submitted electronically on TRC website. Each of the proposals submitted to TRC is selected through a rigorous reviewing and screening process. Novelty and originality of the research idea is the most crucial element in writing a research proposal. Performing an in-depth review of the literature will assist you to compose a good researchable question and generate a strong hypothesis. The development of a good hypothesis will offer insight into the specific objectives of a study. Research objectives should be focused, measurable, and achievable by a specific time using the most appropriate methodology. Moreover, it is essential to select a proper study design in-line with the purpose of the study and the hypothesis. Furthermore, social/economic impact and reasonable budget of proposed research are important criteria in research proposal evaluation by TRC. Finally, ethical principles should be observed before writing a research proposal involving human or animal subjects.

  9. 76 FR 38397 - Agency Information Collection Activities; Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-30

    ... National and State health care reforms; (2) To provide descriptive data on the current employer-sponsored..., and academic researchers to evaluate current and proposed health policies and to support the...

  10. 78 FR 57157 - Agency Information Collection Activities: Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-17

    ...) To provide descriptive data on the current employer-sponsored health insurance system and data for... researchers to evaluate current and proposed health policies and to support the production of important...

  11. 78 FR 38979 - Agency Information Collection Activities; Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-28

    ...) To provide descriptive data on the current employer-sponsored health insurance system and data for... researchers to evaluate current and proposed health policies and to support the production of important...

  12. Iowa DOT library services, collection & technology assessment.

    DOT National Transportation Integrated Search

    2014-07-01

    Assesses the impact of library services on research projects, proposes methods to improve the impact of : library services on research projects, assesses current library technology systems and proposes upgrades, : assesses current library collection ...

  13. Identification of pavement marking colors.

    DOT National Transportation Integrated Search

    2002-04-01

    Current pavement marking color specifications are given in terms of a single color with no indication of acceptable tolerances. Recently proposed standards include tolerances, but neither current nor proposed standards are based on psychophysical dat...

  14. High Performance CMOS Light Detector with Dark Current Suppression in Variable-Temperature Systems.

    PubMed

    Lin, Wen-Sheng; Sung, Guo-Ming; Lin, Jyun-Long

    2016-12-23

    This paper presents a dark current suppression technique for a light detector in a variable-temperature system. The light detector architecture comprises a photodiode for sensing the ambient light, a dark current diode for conducting dark current suppression, and a current subtractor that is embedded in the current amplifier with enhanced dark current cancellation. The measured dark current of the proposed light detector is lower than that of the epichlorohydrin photoresistor or cadmium sulphide photoresistor. This is advantageous in variable-temperature systems, especially for those with many infrared light-emitting diodes. Experimental results indicate that the maximum dark current of the proposed current amplifier is approximately 135 nA at 125 °C, a near zero dark current is achieved at temperatures lower than 50 °C, and dark current and temperature exhibit an exponential relation at temperatures higher than 50 °C. The dark current of the proposed light detector is lower than 9.23 nA and the linearity is approximately 1.15 μA/lux at an external resistance R SS = 10 kΩ and environmental temperatures from 25 °C to 85 °C.

  15. High Performance CMOS Light Detector with Dark Current Suppression in Variable-Temperature Systems

    PubMed Central

    Lin, Wen-Sheng; Sung, Guo-Ming; Lin, Jyun-Long

    2016-01-01

    This paper presents a dark current suppression technique for a light detector in a variable-temperature system. The light detector architecture comprises a photodiode for sensing the ambient light, a dark current diode for conducting dark current suppression, and a current subtractor that is embedded in the current amplifier with enhanced dark current cancellation. The measured dark current of the proposed light detector is lower than that of the epichlorohydrin photoresistor or cadmium sulphide photoresistor. This is advantageous in variable-temperature systems, especially for those with many infrared light-emitting diodes. Experimental results indicate that the maximum dark current of the proposed current amplifier is approximately 135 nA at 125 °C, a near zero dark current is achieved at temperatures lower than 50 °C, and dark current and temperature exhibit an exponential relation at temperatures higher than 50 °C. The dark current of the proposed light detector is lower than 9.23 nA and the linearity is approximately 1.15 μA/lux at an external resistance RSS = 10 kΩ and environmental temperatures from 25 °C to 85 °C. PMID:28025530

  16. Reforming EIA systems: A critical review of proposals in Brazil

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

    Fonseca, Alberto, E-mail: albertof@em.ufop.br; Sánchez, Luis Enrique; Ribeiro, José Claudio Junqueira

    Environmental Impact Assessment (EIA) systems are under pressure in many countries, driven by a call for efficiency and streamlining. Such a phenomenon is particularly clear in Brazil, where, in the past few years, a number of influential associations put forward documents proposing significant changes to environmental licensing and impact assessment regulations. So far, there is no publicly available information about any initiative towards scrutinizing those proposals. The objective of this study was to critically review the merits and drawbacks of the changes proposed in those documents. The analysis triangulated content analysis, focus group and online survey data. The focus groupmore » included ten seasoned Brazilian EIA specialists; the survey, based on Likert-scale and open-ended questions, resulted in 322 valid responses from EIA professionals. Results show that the proposals generally agree that the current EIA system, while playing a key role in mitigating impacts and enhancing project design, needs many changes. Nonetheless, the proposals neither offered solutions to overcome political, technical and budget barriers, nor established a sense of priority of the most urgent issues. Findings from the focus group and the survey signaled that a number of proposed actions might face public outcry, and that those changes that do not depend on legislative action are more likely to be implementable. Previous studies about EIA reform focused mostly on the context of developed countries after changes had taken place. This study, while addressing the perspective of a large developing country in a “before-reform” stage, shows that capacity-building is a key requirement in EIA reform. - Highlights: • Brazil's EIA system is under strong pressure for change. • Findings corroborate ineffectiveness in current system. • There are tensions as to the best approaches to overcome problems. • Exact effects of proposals are uncertain. • Low institutional capacity can play strong role in driving EIA reform.« less

  17. Current situation of International Organization for Standardization/Technical Committee 249 international standards of traditional Chinese medicine.

    PubMed

    Liu, Yu-Qi; Wang, Yue-Xi; Shi, Nan-Nan; Han, Xue-Jie; Lu, Ai-Ping

    2017-05-01

    To review the current situation and progress of traditional Chinese medicine (TCM) international standards, standard projects and proposals in International Organization for Standardization (ISO)/ technical committee (TC) 249. ISO/TC 249 standards and standard projects on the ISO website were searched and new standard proposals information were collected from ISO/TC 249 National Mirror Committee in China. Then all the available data were summarized in 5 closely related items, including proposed time, proposed country, assigned working group (WG), current stage and classifification. In ISO/TC 249, there were 2 international standards, 18 standard projects and 24 new standard proposals proposed in 2014. These 44 standard subjects increased year by year since 2011. Twenty-nine of them were proposed by China, 15 were assigned to WG 4, 36 were in preliminary and preparatory stage and 8 were categorized into 4 fifields, 7 groups and sub-groups based on International Classifification Standards. A rapid and steady development of international standardization in TCM can be observed in ISO/TC 249.

  18. Robust current control-based generalized predictive control with sliding mode disturbance compensation for PMSM drives.

    PubMed

    Liu, Xudong; Zhang, Chenghui; Li, Ke; Zhang, Qi

    2017-11-01

    This paper addresses the current control of permanent magnet synchronous motor (PMSM) for electric drives with model uncertainties and disturbances. A generalized predictive current control method combined with sliding mode disturbance compensation is proposed to satisfy the requirement of fast response and strong robustness. Firstly, according to the generalized predictive control (GPC) theory based on the continuous time model, a predictive current control method is presented without considering the disturbance, which is convenient to be realized in the digital controller. In fact, it's difficult to derive the exact motor model and parameters in the practical system. Thus, a sliding mode disturbance compensation controller is studied to improve the adaptiveness and robustness of the control system. The designed controller attempts to combine the merits of both predictive control and sliding mode control, meanwhile, the controller parameters are easy to be adjusted. Lastly, the proposed controller is tested on an interior PMSM by simulation and experiment, and the results indicate that it has good performance in both current tracking and disturbance rejection. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Update on the Governor's Proposed 2009-10 Budget. Report 09-01

    ERIC Educational Resources Information Center

    Woolfork, Kevin

    2009-01-01

    On December 31, 2008, Governor Arnold Schwarzenegger released the summary of his proposed budget for fiscal year 2009-10, including proposed changes to the current year (2008-09) budget. The complete budget was released on January 9, 2009. The budget plans assume current-year General Fund revenues of $91 billion--down from September's $102 billion…

  20. An adaptable walking-skid for seabed ROV under strong current disturbance

    NASA Astrophysics Data System (ADS)

    Si, Jianting; Chin, Chengsiong

    2014-09-01

    This paper proposed a new concept of an adaptable multi-legged skid design for retro-fitting to a remotely-operated vehicle (ROV) during high tidal current underwater pipeline inspection. The sole reliance on propeller-driven propulsion for ROV is replaced with a proposed low cost biomimetic solution in the form of an attachable hexapod walking skid. The advantage of this adaptable walking skid is the high stability in positioning and endurances to strong current on the seabed environment. The computer simulation flow studies using Solidworks Flow Simulation shown that the skid attachment in different compensation postures caused at least four times increase in overall drag, and negative lift forces on the seabed ROV to achieve a better maneuvering and station keeping under the high current condition (from 0.5 m/s to 5.0 m/s). A graphical user interface is designed to interact with the user during robot-in-the-loop testing and kinematics simulation in the pool.

  1. Anticipated Guilt as Behavioral Motivation: An Examination of Appeals to Help Unknown Others through Bone Marrow Donation

    ERIC Educational Resources Information Center

    Lindsey, Lisa L. Massi

    2005-01-01

    The current study posits that messages used to elicit behaviors to help unknown others must present substantial perceptions of a threat and efficacy to be successful. Given that many prosocial helping messages depict a threat to unknown others, the current investigation proposed that anticipated guilt is a motivating force behind individuals'…

  2. Communicating the wildland fire message: Influences on knowledge and attitude change in two case studies

    Treesearch

    Eric Toman; Bruce Shindler

    2006-01-01

    Current wildland fire policy calls for citizen involvement in planning and management. To be effective in their efforts to engage outside stakeholders, resource professionals need to understand citizens’ understanding and attitudes toward current practices as well as how to best communicate about proposed actions. A variety of outreach methods have been used to...

  3. The opinion of Turkish cardiologists on current malpractice system and an alternative patient compensation system proposal: PCS study group.

    PubMed

    Olcay, Ayhan; Emren, Sadık Volkan; Babür Güler, Gamze; Güler, Ekrem; Ertunç, Vedat; Berilgen, Rida; Aslan, Abdullah; Şimşek, Ersin Çağrı; Gölcük, Şükriye Ebru; Yalın, Kıvanç

    2017-10-01

    Cardiologists participate in the diagnosis and interventional treatment of numerous high-risk patients. The goal of this study was to investigate how the current malpractice system in Turkey influences cardiologists' diagnostic and interventional behavior and to obtain their opinions about an alternative patient compensation system. The present cross-sectional study assessed the practice of defensive medicine among cardiologists who are actively working in various types of workplace within the Turkish healthcare system. A 24-item questionnaire was distributed to cardiology residents, specialists, and academics in Turkey in print format, by electronic mail, or via cell phone message. A total of 253 cardiologists responded to the survey. Among them, 29 (11.6%) had been sued for malpractice claims in the past. Of the cardiologists who had been sued, 2 (6.9%) had been ordered to pay financial compensation, and 1 (3.4%) was given a sentence of imprisonment due to negligence. In all, 132 (52.8%) of the surveyed cardiologists reported that they had changed their practices due to fear of litigation, and 232 (92.8%) reported that they would prefer the new proposed patient compensation system to the current malpractice system. Among the cardiologists surveyed, 78.8% indicated that malpractice fear had affected their decision-making with regard to requesting computed tomography angiography or thallium scintigraphy, 71.6% for coronary angiography, 20% for stent implantation, and 83.2% for avoiding treating high-risk patients. The results of this survey demonstrated that cardiologists may request unnecessary tests and perform unneeded interventions due to the fear of malpractice litigation fear. Many also avoid high-risk patients and interventions. The majority indicated that they would prefer the proposed alternative patient compensation system to the current malpractice system.

  4. Anisotropic conductivity imaging with MREIT using equipotential projection algorithm.

    PubMed

    Değirmenci, Evren; Eyüboğlu, B Murat

    2007-12-21

    Magnetic resonance electrical impedance tomography (MREIT) combines magnetic flux or current density measurements obtained by magnetic resonance imaging (MRI) and surface potential measurements to reconstruct images of true conductivity with high spatial resolution. Most of the biological tissues have anisotropic conductivity; therefore, anisotropy should be taken into account in conductivity image reconstruction. Almost all of the MREIT reconstruction algorithms proposed to date assume isotropic conductivity distribution. In this study, a novel MREIT image reconstruction algorithm is proposed to image anisotropic conductivity. Relative anisotropic conductivity values are reconstructed iteratively, using only current density measurements without any potential measurement. In order to obtain true conductivity values, only either one potential or conductivity measurement is sufficient to determine a scaling factor. The proposed technique is evaluated on simulated data for isotropic and anisotropic conductivity distributions, with and without measurement noise. Simulation results show that the images of both anisotropic and isotropic conductivity distributions can be reconstructed successfully.

  5. A Study of Biblical Sources of Management Principles.

    DTIC Science & Technology

    1976-07-01

    to, currently identified and accepted management principles. The remaining five principles found in the Biblical source have definite United States Air Force application and are offered as proposed principles of management .

  6. Marine Corps Requirements and Procedures for Decontamination and Collective Protection Study. Volume 1.

    DTIC Science & Technology

    1982-08-01

    results of changing selected independent variables. ri The results of the projection of chemical agent density and cloud drift, including dissapation and... combination of agent effects, creates, over time, an extensive threat to wide areas of the FBHA, according to current theories. Shifting wind patterns...will be proposed in paragraph 2.7. The selection of decontamination equipment by the study team is a result of a combination of factors. First, current

  7. United States-Federal Republic of Germany cooperative study of advanced ground vehicle ride quality

    DOT National Transportation Integrated Search

    1979-11-01

    In the first phase of this study, the relative comfort : assoiciated with various speed-guideway configurations for a proposed : magnetically levitated vehicle (Figure 1) and for a currently : operating Bundesbahn rail-coach were determined. The ride...

  8. Permeability and stability of base and subbase materials : appendices A-Q, August 2000.

    DOT National Transportation Integrated Search

    2000-08-01

    This study determined the hydraulic conductivities, effective porosities and resilient moduli of several current and proposed drainable base materials. The materials studied were AASHTO No. 57, AASHTO No. 67, ODOT No. 304, ODOT No. 310, Iowa DOT No. ...

  9. Permeability and stability of base and subbase materials : final report, August 2000.

    DOT National Transportation Integrated Search

    2000-08-01

    This study determined the hydraulic conductivities, effective porosities and resilient moduli of several current and proposed drainable base materials. The materials studied were AASHTO No. 57, AASHTO No. 67, ODOT No. 304, ODOT No. 310, Iowa DOT No. ...

  10. Permeability and stability of base and subbase materials : executive summary, August 2000.

    DOT National Transportation Integrated Search

    2000-08-01

    This study determined the hydraulic conductivities, effective porosities and resilient moduli of several current and proposed drainable base materials. The materials studied were AASHTO No. 57, AASHTO No. 67, ODOT No. 304, ODOT No. 310, Iowa DOT No. ...

  11. Beyond the theoretical rhetoric: a proposal to study the consequences of drug legalization.

    PubMed

    Yacoubian, G S

    2001-01-01

    Drug legalization is a frequently-debated drug control policy alternative. It should come as little surprise, therefore, that the arguments in favor of both legalization and prohibition have resulted in a conceptual stalemate. While theoretical deliberations are unquestionably valuable, they seem to have propelled this particular issue to its limit. To date, no works have suggested any empirical studies that might test the framework and potential consequences of drug legalization. In the current study, the arguments surrounding the drug legalization debate are synthesized into a proposal for future research. Such a proposal illustrates that the core elements surrounding drug legalization are not only testable, but that the time may be right to consider such an empirical effort.

  12. 76 FR 57048 - Agency Information Collection Activities: Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-15

    ... National and State health care reforms; (2) to provide descriptive data on the current employer-sponsored... for Federal, State, and academic researchers to evaluate current and proposed health policies and to...

  13. Modified Johnson-Cook model incorporated with electroplasticity for uniaxial tension under a pulsed electric current

    NASA Astrophysics Data System (ADS)

    Kim, Moon-Jo; Jeong, Hye-Jin; Park, Ju-Won; Hong, Sung-Tae; Han, Heung Nam

    2018-01-01

    An empirical expression describing the electroplastic deformation behavior is suggested based on the Johnson-Cook (JC) model by adding several functions to consider both thermal and athermal electric current effects. Tensile deformation behaviors are carried out for an AZ31 magnesium alloy and an Al-Mg-Si alloy under pulsed electric current at various current densities with a fixed duration of electric current. To describe the flow curves under electric current, a modified JC model is proposed to take the electric current effect into account. Phenomenological descriptions of the adopted parameters in the equation are made. The modified JC model suggested in the present study is capable of describing the tensile deformation behaviors under pulsed electric current reasonably well.

  14. Electromagnetic field radiation model for lightning strokes to tall structures

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

    Motoyama, H.; Janischewskyj, W.; Hussein, A.M.

    1996-07-01

    This paper describes observation and analysis of electromagnetic field radiation from lightning strokes to tall structures. Electromagnetic field waveforms and current waveforms of lightning strokes to the CN Tower have been simultaneously measured since 1991. A new calculation model of electromagnetic field radiation is proposed. The proposed model consists of the lightning current propagation and distribution model and the electromagnetic field radiation model. Electromagnetic fields calculated by the proposed model, based on the observed lightning current at the CN Tower, agree well with the observed fields at 2km north of the tower.

  15. 76 FR 28216 - Meeting of the Chief of Naval Operations Executive Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-16

    ... Operations (CNO) Executive Panel will deliberate on the findings and proposed recommendations of the Resource Sponsorship Subcommittee study. The meeting will consist of discussions regarding the current Navy functional...

  16. Enhancing High Value Care in Gastroenterology Practice.

    PubMed

    Camilleri, Michael; Katzka, David A

    2016-10-01

    The objective of this review is to identify common areas in gastroenterology practice where studies performed provide an opportunity for enhancing value or lowering costs. We provide examples of topics in gastroenterology where clinicians could enhance value by either using less invasive testing, choosing a single best test, or by using patient symptoms to guide additional testing. The topics selected for review are selected in esophageal, pancreatic, and colorectal cancer; functional gastrointestinal diseases (irritable bowel syndrome, bacterial overgrowth, constipation); immune-mediated gastrointestinal diseases; and pancreaticobiliary pathology. We propose guidance to alter practice based on current evidence. These studies support the need to review current practice and to continue performing research to further validate the proposed guidance to enhance value of care in gastroenterology and hepatology. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

  17. Optimization of focality and direction in dense electrode array transcranial direct current stimulation (tDCS)

    NASA Astrophysics Data System (ADS)

    Guler, Seyhmus; Dannhauer, Moritz; Erem, Burak; Macleod, Rob; Tucker, Don; Turovets, Sergei; Luu, Phan; Erdogmus, Deniz; Brooks, Dana H.

    2016-06-01

    Objective. Transcranial direct current stimulation (tDCS) aims to alter brain function non-invasively via electrodes placed on the scalp. Conventional tDCS uses two relatively large patch electrodes to deliver electrical current to the brain region of interest (ROI). Recent studies have shown that using dense arrays containing up to 512 smaller electrodes may increase the precision of targeting ROIs. However, this creates a need for methods to determine effective and safe stimulus patterns as the number of degrees of freedom is much higher with such arrays. Several approaches to this problem have appeared in the literature. In this paper, we describe a new method for calculating optimal electrode stimulus patterns for targeted and directional modulation in dense array tDCS which differs in some important aspects with methods reported to date. Approach. We optimize stimulus pattern of dense arrays with fixed electrode placement to maximize the current density in a particular direction in the ROI. We impose a flexible set of safety constraints on the current power in the brain, individual electrode currents, and total injected current, to protect subject safety. The proposed optimization problem is convex and thus efficiently solved using existing optimization software to find unique and globally optimal electrode stimulus patterns. Main results. Solutions for four anatomical ROIs based on a realistic head model are shown as exemplary results. To illustrate the differences between our approach and previously introduced methods, we compare our method with two of the other leading methods in the literature. We also report on extensive simulations that show the effect of the values chosen for each proposed safety constraint bound on the optimized stimulus patterns. Significance. The proposed optimization approach employs volume based ROIs, easily adapts to different sets of safety constraints, and takes negligible time to compute. An in-depth comparison study gives insight into the relationship between different objective criteria and optimized stimulus patterns. In addition, the analysis of the interaction between optimized stimulus patterns and safety constraint bounds suggests that more precise current localization in the ROI, with improved safety criterion, may be achieved by careful selection of the constraint bounds.

  18. 76 FR 52901 - Airworthiness Directives; The Boeing Company Model 757-200, -200PF, and -200CB Series Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... if necessary. This proposed AD would also add an option for the high frequency eddy current... also adds an optional ultrasonic inspection for the high frequency eddy current inspection to detect... proposed AD would also add an option for the high frequency eddy current inspection for cracking of the...

  19. Analysis of the proposed EU regulation concerning biocide products and its opportunities for alternative approaches and a toxicology for the 21st century (t4 report).

    PubMed

    Ferrario, Daniele; Rabbit, Richard R

    2012-01-01

    On June 12, 2009, the European Commission adopted a proposal for a Regulation concerning the placement on the market and use of biocidal products, which, when it enters into force on January 1, 2013, will repeal and replace Directive 98/8/EC. The main reason for the revision of the current Directive was to promote best practices for environmental and human health protection, along with implementation of current developments in safety testing in order to create safer biocides. Moreover, the proposed Regulation aims to take into consideration the newest legislation on chemicals. This article evaluates the proposed Regulation in comparison to Directive 98/8/EC. Although the new proposal requires the sharing of vertebrate animal test data, both for product authorization and for newly developed active substances, it misses - in contrast to REACH - the opportunity to recognize the accelerating development of alternative approaches to animal testing, most recently with new momentum provided by "Toxicity Testing for the 21st Century", and to support the evolution of toxicology towards a new approach to testing. The new methods promise not only to decrease animal pain and suffering, but also to provide faster results and better prediction for human risk assessment compared to traditional methods. Unfortunately, methods mandated for human risk assessment in the proposal are still mainly based on traditional animal study extrapolation. We put forward and discuss possible alternative strategies, such as in vitro testing, integrated testing strategies, toxicokinetics, "omics", systems biology, bioinformatics, and computational modeling, all of which could be more encouraged by the proposal. Current opportunities to improve our tools for biocide risk assessment are discussed, delineating advantages, limitations, and development needs. It is suggested to open the proposed Regulation to alternative approaches that are based on human biology more than on extrapolation from animals to humans.

  20. Deliberate or unintended: Intentions modulate empathic responses to others' economic payoffs in social interactions.

    PubMed

    Ma, Qingguo; Meng, Liang; Shen, Qiang

    2017-12-01

    Previous studies examining empathy have revealed the neural substrates of how the physical pain of others is represented in the human brain. However, little is known about the empathic modulation of behavioral and neural responses to others' economic payoffs, especially in the social context. In the present study, we engaged participants in a revised Dictator Game as observers who observe the powerless players receiving varied offers proposed by the dominant players, establishing the link between empathy and fairness perception. Results showed that unfair division schemes elicited a more pronounced FRN than fair ones only if a human agent proposed the initial offer. In addition, observers sacrificed their own payments to adjust unfair proposals, especially when a human agent proposed the offer. Thus, results of the current study demonstrated that perceived intention modulates behavioral and neural responses to others' economic payoffs in social interactions.

  1. A new low voltage level-shifted FVF current mirror with enhanced bandwidth and output resistance

    NASA Astrophysics Data System (ADS)

    Aggarwal, Bhawna; Gupta, Maneesha; Gupta, Anil Kumar; Sangal, Ankur

    2016-10-01

    This paper proposes a new high-performance level-shifted flipped voltage follower (LSFVF) based low-voltage current mirror (CM). The proposed CM utilises the low-supply voltage and low-input resistance characteristics of a flipped voltage follower (FVF) CM. In the proposed CM, level-shifting configuration is used to obtain a wide operating current range and resistive compensation technique is employed to increase the operating bandwidth. The peaking in frequency response is reduced by using an additional large MOSFET. Moreover, a very high output resistance (in GΩ range) along with low-current transfer error is achieved through super-cascode configuration for a wide current range (0-440 µA). Small signal analysis is carried out to show the improvements achieved at each step. The proposed CM is simulated by Mentor Graphics Eldospice in TSMC 0.18 µm CMOS, BSIM3 and Level 53 technology. In the proposed CM, a bandwidth of 6.1799 GHz, 1% settling time of 0.719 ns, input and output resistances of 21.43 Ω and 1.14 GΩ, respectively, are obtained with a single supply voltage of 1 V. The layout of the proposed CM has been designed and post-layout simulation results have been shown. The post-layout simulation results for Monte Carlo and temperature analysis have also been included to show the reliability of the CM against the variations in process parameters and temperature changes.

  2. Performance of Four-Leg VSC based DSTATCOM using Single Phase P-Q Theory

    NASA Astrophysics Data System (ADS)

    Jampana, Bangarraju; Veramalla, Rajagopal; Askani, Jayalaxmi

    2017-02-01

    This paper presents single-phase P-Q theory for four-leg VSC based distributed static compensator (DSTATCOM) in the distribution system. The proposed DSTATCOM maintains unity power factor at source, zero voltage regulation, eliminates current harmonics, load balancing and neutral current compensation. The advantage of using four-leg VSC based DSTATCOM is to eliminate isolated/non-isolated transformer connection at point of common coupling (PCC) for neutral current compensation. The elimination of transformer connection at PCC with proposed topology will reduce cost of DSTATCOM. The single-phase P-Q theory control algorithm is used to extract fundamental component of active and reactive currents for generation of reference source currents which is based on indirect current control method. The proposed DSTATCOM is modelled and the results are validated with various consumer loads under unity power factor and zero voltage regulation modes in the MATLAB R2013a environment using simpower system toolbox.

  3. 78 FR 19746 - Biweekly Notice; Applications and Amendments to Facility Operating Licenses and Combined Licenses...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-02

    ... proposed change would not change the current limiting EDG [emergency diesel generator] failure but would... evaluated? Response: No. The proposed change would not change the current EDG [emergency diesel generator...

  4. Optimized Controller Design for a 12-Pulse Voltage Source Converter Based HVDC System

    NASA Astrophysics Data System (ADS)

    Agarwal, Ruchi; Singh, Sanjeev

    2017-12-01

    The paper proposes an optimized controller design scheme for power quality improvement in 12-pulse voltage source converter based high voltage direct current system. The proposed scheme is hybrid combination of golden section search and successive linear search method. The paper aims at reduction of current sensor and optimization of controller. The voltage and current controller parameters are selected for optimization due to its impact on power quality. The proposed algorithm for controller optimizes the objective function which is composed of current harmonic distortion, power factor, and DC voltage ripples. The detailed designs and modeling of the complete system are discussed and its simulation is carried out in MATLAB-Simulink environment. The obtained results are presented to demonstrate the effectiveness of the proposed scheme under different transient conditions such as load perturbation, non-linear load condition, voltage sag condition, and tapped load fault under one phase open condition at both points-of-common coupling.

  5. Justifying Study Abroad in Financially Difficult Times

    ERIC Educational Resources Information Center

    Ludlum, Marty; Ice, Randal; Sheetz-Nguyen, Jessica

    2013-01-01

    In this paper, we will develop the justification for study abroad. We will discuss the current economic climate and its impact on budgets. Next, we will explain the many benefits of the study abroad programs. Then we will propose some less expensive alternatives to the traditional study abroad programs. We will conclude with expectations for the…

  6. European Union bulk tank SCC standards and proposed US standards: Compliance based on data from four Federal Milk Marketing Orders

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to evaluate compliance of US producers with the proposed BTSCC limits. Four different SCC levels of compliance were evaluated: 750K; 600K; 500K; 400K. For the 12 month period ending October 2010, 1.0% of producers and 0.2% of milk exceeded the current US limit of 750K...

  7. Targeting Neuronal-like Metabolism of Metastatic Tumor Cells as a Novel Therapy for Breast Cancer Brain Metastasis

    DTIC Science & Technology

    2016-03-01

    Currently, no effective drug treatments are available for brain metastasis. In this proposal, we hypothesize: interactions with reactive brain astrocytes...neurological drugs . In this project, we propose two specific aims to explore the functional importance of the early metastatic evolution and the...feasibility of targeting metastatic evolution by repurposing neurological drugs . Aim 1: Study the spatial and temporal interactions between brain

  8. The study of the stress - strain state of the tank with bottom water drainage during operation

    NASA Astrophysics Data System (ADS)

    Shchipkova, Yu V.; Tokarev, V. V.

    2018-04-01

    Bottom drainage from tank is a current problem in modern tank usage. This article proposes the use of the bottom drainage system from the tank with the shape of the sloped cone to the centre of it. Changing the bottom design alters the stress - strain state to be analyzed in the Ansys. The analysis concluded that the proposed drainage system should be applied.

  9. Shilling attack detection for recommender systems based on credibility of group users and rating time series.

    PubMed

    Zhou, Wei; Wen, Junhao; Qu, Qiang; Zeng, Jun; Cheng, Tian

    2018-01-01

    Recommender systems are vulnerable to shilling attacks. Forged user-generated content data, such as user ratings and reviews, are used by attackers to manipulate recommendation rankings. Shilling attack detection in recommender systems is of great significance to maintain the fairness and sustainability of recommender systems. The current studies have problems in terms of the poor universality of algorithms, difficulty in selection of user profile attributes, and lack of an optimization mechanism. In this paper, a shilling behaviour detection structure based on abnormal group user findings and rating time series analysis is proposed. This paper adds to the current understanding in the field by studying the credibility evaluation model in-depth based on the rating prediction model to derive proximity-based predictions. A method for detecting suspicious ratings based on suspicious time windows and target item analysis is proposed. Suspicious rating time segments are determined by constructing a time series, and data streams of the rating items are examined and suspicious rating segments are checked. To analyse features of shilling attacks by a group user's credibility, an abnormal group user discovery method based on time series and time window is proposed. Standard testing datasets are used to verify the effect of the proposed method.

  10. The Performance Analysis of a 3d Map Embedded Ins/gps Fusion Algorithm for Seamless Vehicular Navigation in Elevated Highway Environments

    NASA Astrophysics Data System (ADS)

    Lee, Y. H.; Chiang, K. W.

    2012-07-01

    In this study, a 3D Map Matching (3D MM) algorithm is embedded to current INS/GPS fusion algorithm for enhancing the sustainability and accuracy of INS/GPS integration systems, especially the height component. In addition, this study propose an effective solutions to the limitation of current commercial vehicular navigation systems where they fail to distinguish whether the vehicle is moving on the elevated highway or the road under it because those systems don't have sufficient height resolution. To validate the performance of proposed 3D MM embedded INS/GPS integration algorithms, in the test area, two scenarios were considered, paths under the freeways and streets between tall buildings, where the GPS signal is obstacle or interfered easily. The test platform was mounted on the top of a land vehicle and also systems in the vehicle. The IMUs applied includes SPAN-LCI (0.1 deg/hr gyro bias) from NovAtel, which was used as the reference system, and two MEMS IMUs with different specifications for verifying the performance of proposed algorithm. The preliminary results indicate the proposed algorithms are able to improve the accuracy of positional components in GPS denied environments significantly with the use of INS/GPS integrated systems in SPP mode.

  11. Shilling attack detection for recommender systems based on credibility of group users and rating time series

    PubMed Central

    Wen, Junhao; Qu, Qiang; Zeng, Jun; Cheng, Tian

    2018-01-01

    Recommender systems are vulnerable to shilling attacks. Forged user-generated content data, such as user ratings and reviews, are used by attackers to manipulate recommendation rankings. Shilling attack detection in recommender systems is of great significance to maintain the fairness and sustainability of recommender systems. The current studies have problems in terms of the poor universality of algorithms, difficulty in selection of user profile attributes, and lack of an optimization mechanism. In this paper, a shilling behaviour detection structure based on abnormal group user findings and rating time series analysis is proposed. This paper adds to the current understanding in the field by studying the credibility evaluation model in-depth based on the rating prediction model to derive proximity-based predictions. A method for detecting suspicious ratings based on suspicious time windows and target item analysis is proposed. Suspicious rating time segments are determined by constructing a time series, and data streams of the rating items are examined and suspicious rating segments are checked. To analyse features of shilling attacks by a group user’s credibility, an abnormal group user discovery method based on time series and time window is proposed. Standard testing datasets are used to verify the effect of the proposed method. PMID:29742134

  12. DSMC Simulations of Hypersonic Flows and Comparison With Experiments

    NASA Technical Reports Server (NTRS)

    Moss, James N.; Bird, Graeme A.; Markelov, Gennady N.

    2004-01-01

    This paper presents computational results obtained with the direct simulation Monte Carlo (DSMC) method for several biconic test cases in which shock interactions and flow separation-reattachment are key features of the flow. Recent ground-based experiments have been performed for several biconic configurations, and surface heating rate and pressure measurements have been proposed for code validation studies. The present focus is to expand on the current validating activities for a relatively new DSMC code called DS2V that Bird (second author) has developed. Comparisons with experiments and other computations help clarify the agreement currently being achieved between computations and experiments and to identify the range of measurement variability of the proposed validation data when benchmarked with respect to the current computations. For the test cases with significant vibrational nonequilibrium, the effect of the vibrational energy surface accommodation on heating and other quantities is demonstrated.

  13. Correlated spin currents generated by resonant-crossed Andreev reflections in topological superconductors

    PubMed Central

    He, James J.; Wu, Jiansheng; Choy, Ting-Pong; Liu, Xiong-Jun; Tanaka, Y.; Law, K. T.

    2014-01-01

    Topological superconductors, which support Majorana fermion excitations, have been the subject of intense studies due to their novel transport properties and their potential applications in fault-tolerant quantum computations. Here we propose a new type of topological superconductors that can be used as a novel source of correlated spin currents. We show that inducing superconductivity on a AIII class topological insulator wire, which respects a chiral symmetry and supports protected fermionic end states, will result in a topological superconductor. This topological superconductor supports two topological phases with one or two Majorana fermion end states, respectively. In the phase with two Majorana fermions, the superconductor can split Cooper pairs efficiently into electrons in two spatially separated leads due to Majorana-induced resonant-crossed Andreev reflections. The resulting currents in the leads are correlated and spin-polarized. Importantly, the proposed topological superconductors can be realized using quantum anomalous Hall insulators in proximity to superconductors. PMID:24492649

  14. A robust cooperative spectrum sensing scheme based on Dempster-Shafer theory and trustworthiness degree calculation in cognitive radio networks

    NASA Astrophysics Data System (ADS)

    Wang, Jinlong; Feng, Shuo; Wu, Qihui; Zheng, Xueqiang; Xu, Yuhua; Ding, Guoru

    2014-12-01

    Cognitive radio (CR) is a promising technology that brings about remarkable improvement in spectrum utilization. To tackle the hidden terminal problem, cooperative spectrum sensing (CSS) which benefits from the spatial diversity has been studied extensively. Since CSS is vulnerable to the attacks initiated by malicious secondary users (SUs), several secure CSS schemes based on Dempster-Shafer theory have been proposed. However, the existing works only utilize the current difference of SUs, such as the difference in SNR or similarity degree, to evaluate the trustworthiness of each SU. As the current difference is only one-sided and sometimes inaccurate, the statistical information contained in each SU's historical behavior should not be overlooked. In this article, we propose a robust CSS scheme based on Dempster-Shafer theory and trustworthiness degree calculation. It is carried out in four successive steps, which are basic probability assignment (BPA), trustworthiness degree calculation, selection and adjustment of BPA, and combination by Dempster-Shafer rule, respectively. Our proposed scheme evaluates the trustworthiness degree of SUs from both current difference aspect and historical behavior aspect and exploits Dempster-Shafer theory's potential to establish a `soft update' approach for the reputation value maintenance. It can not only differentiate malicious SUs from honest ones based on their historical behaviors but also reserve the current difference for each SU to achieve a better real-time performance. Abundant simulation results have validated that the proposed scheme outperforms the existing ones under the impact of different attack patterns and different number of malicious SUs.

  15. Maximizing JWST Science for Dusty White Dwarfs

    NASA Astrophysics Data System (ADS)

    Farihi, Jay; Dennihy, Erik; Gentile Fusillo, Nicola; Debes, John; Gaensicke, Boris

    2018-05-01

    We propose a small program to increase the number of dusty white dwarfs that can be studied in detail by the James Webb Space Telescope. Currently, there are 8 systems for which MIRI MRS spectroscopy can be carried out in less than a few hours per target, and here we propose to double this number. Using cross-correlation of AllWISE photometry with Southern Hemisphere surveys such as Edinburgh-Cape and ATLAS, we have selected the strongest 22 potential dusty white dwarf candidates. We propose to use warm IRAC imaging photometry as the ultimate discriminant between dust and common photometric contaminants. This program has immediate legacy value via detailed mineralogical studies of debris disks using JWST.

  16. GASP-PL/I Simulation of Integrated Avionic System Processor Architectures. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Brent, G. A.

    1978-01-01

    A development study sponsored by NASA was completed in July 1977 which proposed a complete integration of all aircraft instrumentation into a single modular system. Instead of using the current single-function aircraft instruments, computers compiled and displayed inflight information for the pilot. A processor architecture called the Team Architecture was proposed. This is a hardware/software approach to high-reliability computer systems. A follow-up study of the proposed Team Architecture is reported. GASP-PL/1 simulation models are used to evaluate the operating characteristics of the Team Architecture. The problem, model development, simulation programs and results at length are presented. Also included are program input formats, outputs and listings.

  17. Classifying insulin regimens--difficulties and proposal for comprehensive new definitions.

    PubMed

    Neu, A; Lange, K; Barrett, T; Cameron, F; Dorchy, H; Hoey, H; Jarosz-Chobot, P; Mortensen, H B; Robert, J-J; Robertson, K; de Beaufort, C

    2015-09-01

    Modern insulin regimens for the treatment of type 1 diabetes are highly individualized. The concept of an individually tailored medicine accounts for a broad variety of different insulin regimens applied. Despite clear recommendations for insulin management in children and adolescents with type 1 diabetes there is little distinctiveness about concepts and the nomenclature is confusing. Even among experts similar terms are used for different strategies. The aim of our review--based on the experiences of the Hvidoere Study Group (HSG)--is to propose comprehensive definitions for current insulin regimens reflecting current diabetes management in childhood and adolescence. The HSG--founded in 1994--is an international group representing 24 highly experienced pediatric diabetes centers, from Europe, Japan, North America and Australia. Different benchmarking studies of the HSG revealed a broad variety of insulin regimens applied in each center, respectively. Furthermore, the understanding of insulin regimens has been persistently different between the centers since more than 20 yr. Not even the terms 'conventional' and 'intensified therapy' were used consistently among all members. Besides the concepts 'conventional' and 'intensified', several other terms for the characterization of insulin regimens are in use: Basal Bolus Concept (BBC), multiple daily injections (MDI), and flexible insulin therapy (FIT) are most frequently used, although none of these expressions is clearly or consistently defined. The proposed new classification for insulin management will be comprehensive, simple, and catchy. Currently available terms were included. This classification may offer the opportunity to compare therapeutic strategies without the currently existing confusion on the insulin regimen. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

  19. Evaluation of the proposed social anxiety disorder specifier change for DSM-5 in a treatment-seeking sample of anxious youth.

    PubMed

    Kerns, Caroline E; Comer, Jonathan S; Pincus, Donna B; Hofmann, Stefan G

    2013-08-01

    The current proposal for the DSM-5 definition of social anxiety disorder (SAD) is to replace the DSM-IV generalized subtype specifier with one that specifies fears in performance situations only. Relevant evaluations to support this change in youth samples are sparse. The present study examined rates and correlates of the DSM-IV and proposed DSM-5 specifiers in a sample of treatment-seeking children and adolescents with SAD (N = 204). When applying DSM-IV subtypes, 64.2% of the sample was classified as having a generalized subtype of SAD, with the remaining 35.2% classifying as having a nongeneralized subtype SAD. Youth with generalized SAD, relative to those with nongeneralized SAD, were older, had more clinically severe SAD, showed greater depressive symptoms, and were more likely to have a comorbid depressive disorder. No children in the current sample endorsed discrete fear in performance situations only in the absence of fear in other social situations. The present findings call into question the meaningfulness of the proposed changes in treatment-seeking youth with SAD. © 2013 Wiley Periodicals, Inc.

  20. Acoustic wave-driven oxidized liquid metal-based energy harvester

    NASA Astrophysics Data System (ADS)

    Jeon, Jinpyo; Chung, Sang Kug; Lee, Jeong-Bong; Doo, Seok Joo; Kim, Daeyoung

    2018-06-01

    We report an oxidized liquid metal droplet-based energy harvester that converts acoustic energy into electrical energy by modulating an electrical double layer that originates from the deformation of the oxidized liquid metal droplet. Gallium-based liquid metal alloy has been developed for various applications owing to the outstanding material properties, such as its high electrical conductivity (metallic property) and unlimited deformability (liquid property). In this study, we demonstrated energy harvesting using an electrical double layer between the acoustic wave-modulated liquid metal droplet and two electrodes. The proposed energy harvester consisted of top and bottom electrodes covered with the dielectric layer and a Gallium-based liquid metal droplet placed between the electrodes. When we applied an external bias voltage and acoustic wave to the proposed device, the contact area between the liquid metal droplet and the electrodes changed, leading to the variation of the capacitance in the electrical double layer and the generation of electrical output current. Using the proposed energy harvester, the maximum output current of 41.2 nA was generated with an applied acoustic wave of 30 Hz. In addition, we studied the relationships between the maximum output current and a variety of factors, such as the size of the liquid metal droplet, the thickness of the hydrophobic layer, and the distance between the top and bottom electrode plates.

  1. Teaching the Banking System According to Critical Education. A Study of a Schoolbook on Economics

    ERIC Educational Resources Information Center

    Vaina, Maria; Katidioti, Evaggelia; Ktitikos, Antonis

    2013-01-01

    The main objective of the current paper is to establish the deficiencies of teaching Economics in the Greek educational system. It also proposes critical education as a way of partially overcoming these issues and the way it can contribute to the protection of the everyday man and woman against the rising and current existential threats of the…

  2. The usefulness and reliability of fitness testing protocols for ice hockey players: a literature review.

    PubMed

    Nightingale, Steven C; Miller, Stuart; Turner, Anthony

    2013-06-01

    Ice hockey, like most sports, uses fitness testing to assess athletes. This study reviews the current commonly used fitness testing protocols for ice hockey players, discussing their predictive values and reliability. It also discusses a range of less commonly used measures and limitations in current testing protocols. The article concludes with a proposed testing program suitable for ice hockey players.

  3. Novel MCP-Based Electron Source Studies

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

    Haughey, M.; Shiltsev V., Shiltsev V.; Stancari, G.

    Microchannel plates (MCPs) were recently proposed as novel type of cathodes for electron guns [1], suitable for applications in design of electron lenses. We report results of the first systematic study of microchannel plate based photomultiplier time response and maximum cur-rent density tests using different sources of light pulses. The Burle 85011-501 MCP-PMT is found to have good time response properties being capable of producing na-nosecond long pulses with modest maximum current density and performance strongly dependent on magnetic field strength.

  4. Toward a closer integration of magnetospheric research: Magnetospheric currents inferred from ground-based magnetic data

    NASA Astrophysics Data System (ADS)

    Akasofu, S.-I.; Kamide, Y.

    1998-07-01

    A new approach is needed to advance magnetospheric physics in the future to achieve a much closer integration than in the past among satellite-based researchers, ground-based researchers, and theorists/modelers. Specifically, we must find efficient ways to combine two-dimensional ground-based data and single points satellite-based data to infer three-dimensional aspects of magnetospheric disturbances. For this particular integration purpose, we propose a new project. It is designed to determine the currents on the magnetospheric equatorial plane from the ionospheric current distribution which has become available by inverting ground-based magnetic data from an extensive, systematic network of observations, combined with ground-based radar measurements of ionospheric parameters, and satellite observations of auroras, electric fields, and currents. The inversion method is based on the KRM/AMIE algorithms. In the first part of the paper, we extensively review the reliability and accuracy of the KRM and AMIE algorithms and conclude that the ionospheric quantities thus obtained are accurate enough for the next step. In the second part, the ionospheric current distribution thus obtained is projected onto the equatorial plane. This process requires a close cooperation with modelers in determining an accurate configuration of the magnetospheric field lines. If we succeed in this projection, we should be able to study the changing distribution of the currents in a vast region of the magnetospheric equatorial plane for extended periods with a time resolution of about 5 min. This process requires a model of the magnetosphere for the different phases of the magnetospheric substorm. Satellite-based observations are needed to calibrate the projection results. Agreements and disagreements thus obtained will be crucial for theoretical studies of magnetospheric plasma convection and dynamics, particularly in studying substorms. Nothing is easy in these procedures. However, unless we can overcome the associated difficulties, we may not be able to make distinct progresses. We believe that the proposed project is one way to draw the three groups closer together in advancing magnetospheric physics in the future. It is important to note that the proposed project has become possible because ground-based space physics has made a major advance during the last decade.

  5. Underwater Acoustic Wireless Sensor Networks: Advances and Future Trends in Physical, MAC and Routing Layers

    PubMed Central

    Climent, Salvador; Sanchez, Antonio; Capella, Juan Vicente; Meratnia, Nirvana; Serrano, Juan Jose

    2014-01-01

    This survey aims to provide a comprehensive overview of the current research on underwater wireless sensor networks, focusing on the lower layers of the communication stack, and envisions future trends and challenges. It analyzes the current state-of-the-art on the physical, medium access control and routing layers. It summarizes their security threads and surveys the currently proposed studies. Current envisioned niches for further advances in underwater networks research range from efficient, low-power algorithms and modulations to intelligent, energy-aware routing and medium access control protocols. PMID:24399155

  6. A fault-tolerant strategy based on SMC for current-controlled converters

    NASA Astrophysics Data System (ADS)

    Azer, Peter M.; Marei, Mostafa I.; Sattar, Ahmed A.

    2018-05-01

    The sliding mode control (SMC) is used to control variable structure systems such as power electronics converters. This paper presents a fault-tolerant strategy based on the SMC for current-controlled AC-DC converters. The proposed SMC is based on three sliding surfaces for the three legs of the AC-DC converter. Two sliding surfaces are assigned to control the phase currents since the input three-phase currents are balanced. Hence, the third sliding surface is considered as an extra degree of freedom which is utilised to control the neutral voltage. This action is utilised to enhance the performance of the converter during open-switch faults. The proposed fault-tolerant strategy is based on allocating the sliding surface of the faulty leg to control the neutral voltage. Consequently, the current waveform is improved. The behaviour of the current-controlled converter during different types of open-switch faults is analysed. Double switch faults include three cases: two upper switch fault; upper and lower switch fault at different legs; and two switches of the same leg. The dynamic performance of the proposed system is evaluated during healthy and open-switch fault operations. Simulation results exhibit the various merits of the proposed SMC-based fault-tolerant strategy.

  7. Low-sensitivity, low-bounce, high-linearity current-controlled oscillator suitable for single-supply mixed-mode instrumentation system.

    PubMed

    Hwang, Yuh-Shyan; Kung, Che-Min; Lin, Ho-Cheng; Chen, Jiann-Jong

    2009-02-01

    A low-sensitivity, low-bounce, high-linearity current-controlled oscillator (CCO) suitable for a single-supply mixed-mode instrumentation system is designed and proposed in this paper. The designed CCO can be operated at low voltage (2 V). The power bounce and ground bounce generated by this CCO is less than 7 mVpp when the power-line parasitic inductance is increased to 100 nH to demonstrate the effect of power bounce and ground bounce. The power supply noise caused by the proposed CCO is less than 0.35% in reference to the 2 V supply voltage. The average conversion ratio KCCO is equal to 123.5 GHz/A. The linearity of conversion ratio is high and its tolerance is within +/-1.2%. The sensitivity of the proposed CCO is nearly independent of the power supply voltage, which is less than a conventional current-starved oscillator. The performance of the proposed CCO has been compared with the current-starved oscillator. It is shown that the proposed CCO is suitable for single-supply mixed-mode instrumentation systems.

  8. Measurement of high-resolution mechanical contraction of cardiac muscle by induced eddy current.

    PubMed

    Lee, Young-Jae; Lee, Kang-Hwi; Kang, Seung-Jin; Kim, Kyeung-Nam; Khang, Seonah; Koo, Hye Ran; Gi, Sunok; Lee, Joo Hyeon; Lee, Jeong-Whan

    2014-01-01

    There are many types of devices which help to manage a personal health conditions such as heartbeat chest belt, pedometer and smart watch. And the most common device has the relationship with heart rate or ECG data. However, users have to attach some electrode or fasten the belt on the bare skin to measure bio-signal information. Therefore, most of people want more convenient and short-ready-time and no-need to attach electrode. In this paper, we proposed the high-resolution measuring system of mechanical activity of cardiac muscle and thereby measure heartbeat. The principle of the proposed measuring method is that the alternating current generate alternating magnetic field around coil. This primary magnetic field induces eddy current which makes magnetic field against primary coil in the nearby objects. To measure high-resolution changes of the induced secondary magnetic fields, we used digital Phase-locked loop(PLL) circuit which provides more high-resolution traces of frequency changes than the previous studies based on digital frequency counter method. As a result of our preliminary experiment, peak-peak intervals of the proposed method showed high correlation with R-R intervals of clinical ECG signals(r=0.9249). Also, from signal traces of the proposed method, we might make a conjecture that the contraction of atrium or ventricle is reflected by changing conductivity of cardiac muscle which is beating ceaselessly.

  9. Cancer Research Center Indiana University School of Medicine

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

    Not Available

    1994-08-01

    The Department of Energy (DOE) proposes to authorize the Indiana School of Medicine to proceed with the detailed design, construction and equipping of the proposed Cancer Research Center (CRC). A grant was executed with the University on April 21, 1992. A four-story building with basement would be constructed on the proposed site over a 24-month period. The proposed project would bring together, in one building, three existing hematology/oncology basic research programs, with improved cost-effectiveness through the sharing of common resources. The proposed site is currently covered with asphaltic pavement and is used as a campus parking lot. The surrounding areamore » is developed campus, characterized by buildings, walkways, with minimal lawns and plantings. The proposed site has no history of prior structures and no evidence of potential sources of prior contamination of the soil. Environmental impacts of construction would be limited to minor increases in traffic, and the typical noises associated with standard building construction. The proposed CRC project operation would involve the use radionuclides and various hazardous materials in conducting clinical studies. Storage, removal and disposal of hazardous wastes would be managed under existing University programs that comply with federal and state requirements. Radiological safety programs would be governed by Nuclear Regulatory Commission (NRC) license and applicable Environmental Protection Agency (EPA) regulations. There are no other NEPA reviews currently active which are in relationship to this proposed site. The proposed project is part of a Medical Campus master plan and is consistent with applicable local zoning and land use requirements.« less

  10. Questionable validity of left ventricular hypertrophy cutoff values in morbidly and super-morbidly obese patients.

    PubMed

    Domienik-Karłowicz, Justyna; Rymarczyk, Zuzanna; Lisik, Wojciech; Kurnicka, Katarzyna; Ciurzyński, Michał; Bielecki, Maksymilian; Kosieradzki, Maciej; Pruszczyk, Piotr

    2018-06-17

    Current diagnostic ECG criteria of left ventricular hypertrophy in obese patients are still lacking. To assess the current ECG diagnostic criteria of LVH, and to validate our previously proposed criteria in a group of patients with morbid obesity. A group of consecutive 429 obese patients (MOP) with BMI of at least 35 kg/m 2 (mean age 38.6 ± 8.9 years, BMI 48.7 ± 9.0 kg/m 2 ; 323 females, 106 males) were included. The diagnosis of LVH in MOPs was confirmed only by RaVL of 7.5 mm, Cornell index of 12.5 mm; Cornell index × QRS duration of 1,125 mm × ms and Romhilt-Estes score of 1. None of the criteria proposed to date is appropriate in super-morbidly obese patients. Our study confirmed that none of the currently used voltage-based ECG criteria is appropriate for diagnosing LVH in morbidly obese patients. Further studies are required. © 2018 Wiley Periodicals, Inc.

  11. Writing a Research Proposal to The Research Council of Oman

    PubMed Central

    Al-Shukaili, Ahmed; Al-Maniri, Abdullah

    2017-01-01

    Writing a research proposal can be a challenging task for young researchers. This article explains how to write a strong research proposal to apply for funding, specifically, a proposal for The Research Council (TRC) of Oman. Three different research proposal application forms are currently used in TRC, including Open Research Grant (ORG), Graduate Research Support Program (GRSP), and Faculty-mentored Undergraduate Research Award Program (FURAP). The application forms are filled and submitted electronically on TRC website. Each of the proposals submitted to TRC is selected through a rigorous reviewing and screening process. Novelty and originality of the research idea is the most crucial element in writing a research proposal. Performing an in-depth review of the literature will assist you to compose a good researchable question and generate a strong hypothesis. The development of a good hypothesis will offer insight into the specific objectives of a study. Research objectives should be focused, measurable, and achievable by a specific time using the most appropriate methodology. Moreover, it is essential to select a proper study design in-line with the purpose of the study and the hypothesis. Furthermore, social/economic impact and reasonable budget of proposed research are important criteria in research proposal evaluation by TRC. Finally, ethical principles should be observed before writing a research proposal involving human or animal subjects. PMID:28584597

  12. A novel method to optimize the mode spectrum of the dynamic resonant magnetic perturbation on the J-TEXT tokamak.

    PubMed

    Yi, B; Rao, B; Ding, Y H; Li, M; Xu, H Y; Zhang, M; Zhuang, G; Pan, Y

    2014-11-01

    The dynamic resonant magnetic perturbation (DRMP) system has been developed for the J-TEXT tokamak to study the interaction between the rotating perturbation magnetic field and the plasma. When the DRMP coils are energized by two phase sinusoidal currents with the same frequency, a 2/1 rotating resonant magnetic perturbation component will be generated. But at the same time, a small perturbation component rotating in the opposite direction is also produced because of the control error of the currents. This small component has bad influence on the experiment investigations. Actually, the mode spectrum of the generated DRMP can be optimized with an accurate control of phase difference between the two currents. In this paper, a new phase control method based on a novel all-digital phase-locked loop (ADPLL) is proposed. The proposed method features accurate phase control and flexible phase adjustment. Modeling and analysis of the proposed ADPLL is presented to guide the design of the parameters of the phase controller in order to obtain a better performance. Testing results verify the effectiveness of the ADPLL and validity of the method applying to the DRMP system.

  13. A novel method to optimize the mode spectrum of the dynamic resonant magnetic perturbation on the J-TEXT tokamak

    NASA Astrophysics Data System (ADS)

    Yi, B.; Rao, B.; Ding, Y. H.; Li, M.; Xu, H. Y.; Zhang, M.; Zhuang, G.; Pan, Y.

    2014-11-01

    The dynamic resonant magnetic perturbation (DRMP) system has been developed for the J-TEXT tokamak to study the interaction between the rotating perturbation magnetic field and the plasma. When the DRMP coils are energized by two phase sinusoidal currents with the same frequency, a 2/1 rotating resonant magnetic perturbation component will be generated. But at the same time, a small perturbation component rotating in the opposite direction is also produced because of the control error of the currents. This small component has bad influence on the experiment investigations. Actually, the mode spectrum of the generated DRMP can be optimized with an accurate control of phase difference between the two currents. In this paper, a new phase control method based on a novel all-digital phase-locked loop (ADPLL) is proposed. The proposed method features accurate phase control and flexible phase adjustment. Modeling and analysis of the proposed ADPLL is presented to guide the design of the parameters of the phase controller in order to obtain a better performance. Testing results verify the effectiveness of the ADPLL and validity of the method applying to the DRMP system.

  14. Representing and querying now-relative relational medical data.

    PubMed

    Anselma, Luca; Piovesan, Luca; Stantic, Bela; Terenziani, Paolo

    2018-03-01

    Temporal information plays a crucial role in medicine. Patients' clinical records are intrinsically temporal. Thus, in Medical Informatics there is an increasing need to store, support and query temporal data (particularly in relational databases), in order, for instance, to supplement decision-support systems. In this paper, we show that current approaches to relational data have remarkable limitations in the treatment of "now-relative" data (i.e., data holding true at the current time). This can severely compromise their applicability in general, and specifically in the medical context, where "now-relative" data are essential to assess the current status of the patients. We propose a theoretically grounded and application-independent relational approach to cope with now-relative data (which can be paired, e.g., with different decision support systems) overcoming such limitations. We propose a new temporal relational representation, which is the first relational model coping with the temporal indeterminacy intrinsic in now-relative data. We also propose new temporal algebraic operators to query them, supporting the distinction between possible and necessary time, and Allen's temporal relations between data. We exemplify the impact of our approach, and study the theoretical and computational properties of the new representation and algebra. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Study of the generator/motor operation of induction machines in a high frequency link space power system

    NASA Technical Reports Server (NTRS)

    Lipo, Thomas A.; Sood, Pradeep K.

    1987-01-01

    Static power conversion systems have traditionally utilized dc current or voltage source links for converting power from one ac or dc form to another since it readily achieves the temporary energy storage required to decouple the input from the output. Such links, however, result in bulky dc capacitors and/or inductors and lead to relatively high losses in the converters due to stresses on the semiconductor switches. The feasibility of utilizing a high frequency sinusoidal voltage link to accomplish the energy storage and decoupling function is examined. In particular, a type of resonant six pulse bridge interface converter is proposed which utilizes zero voltage switching principles to minimize switching losses and uses an easy to implement technique for pulse density modulation to control the amplitude, frequency, and the waveshape of the synthesized low frequency voltage or current. Adaptation of the proposed topology for power conversion to single-phase ac and dc voltage or current outputs is shown to be straight forward. The feasibility of the proposed power circuit and control technique for both active and passive loads are verified by means of simulation and experiment.

  16. Heterojunction fully depleted SOI-TFET with oxide/source overlap

    NASA Astrophysics Data System (ADS)

    Chander, Sweta; Bhowmick, B.; Baishya, S.

    2015-10-01

    In this work, a hetero-junction fully depleted (FD) Silicon-on-Insulator (SOI) Tunnel Field Effect Transistor (TFET) nanostructure with oxide overlap on the Germanium-source region is proposed. Investigations using Synopsys Technology Computer Aided Design (TCAD) simulation tools reveal that the simple oxide overlap on the Germanium-source region increases the tunneling area as well as the tunneling current without degrading the band-to-band tunneling (BTBT) and improves the device performance. More importantly, the improvement is independent of gate overlap. Simulation study shows improvement in ON current, subthreshold swing (SS), OFF current, ION/IOFF ration, threshold voltage and transconductance. The proposed device with hafnium oxide (HfO2)/Aluminium Nitride (AlN) stack dielectric material offers an average subthreshold swing of 22 mV/decade and high ION/IOFF ratio (∼1010) at VDS = 0.4 V. Compared to conventional TFET, the Miller capacitance of the device shows the enhanced performance. The impact of the drain voltage variation on different parameters such as threshold voltage, subthreshold swing, transconductance, and ION/IOFF ration are also found to be satisfactory. From fabrication point of view also it is easy to utilize the existing CMOS process flows to fabricate the proposed device.

  17. A novel eddy current damper: theory and experiment

    NASA Astrophysics Data System (ADS)

    Ebrahimi, Babak; Khamesee, Mir Behrad; Golnaraghi, Farid

    2009-04-01

    A novel eddy current damper is developed and its damping characteristics are studied analytically and experimentally. The proposed eddy current damper consists of a conductor as an outer tube, and an array of axially magnetized ring-shaped permanent magnets separated by iron pole pieces as a mover. The relative movement of the magnets and the conductor causes the conductor to undergo motional eddy currents. Since the eddy currents produce a repulsive force that is proportional to the velocity of the conductor, the moving magnet and the conductor behave as a viscous damper. The eddy current generation causes the vibration to dissipate through the Joule heating generated in the conductor part. An accurate, analytical model of the system is obtained by applying electromagnetic theory to estimate the damping properties of the proposed eddy current damper. A prototype eddy current damper is fabricated, and experiments are carried out to verify the accuracy of the theoretical model. The experimental test bed consists of a one-degree-of-freedom vibration isolation system and is used for the frequency and transient time response analysis of the system. The eddy current damper model has a 0.1 m s-2 (4.8%) RMS error in the estimation of the mass acceleration. A damping coefficient as high as 53 Ns m-1 is achievable with the fabricated prototype. This novel eddy current damper is an oil-free, inexpensive damper that is applicable in various vibration isolation systems such as precision machinery, micro-mechanical suspension systems and structure vibration isolation.

  18. 75 FR 59724 - Proposed Collection; Comment Request; Transfusion-Transmitted Retrovirus and Hepatitis Virus...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-28

    ...- control study design. (3) Determine nationally-representative infectious disease marker prevalence and... on current risk factors in blood donors as assessed using analytical study designs is largely... in first time donors increased. Moreover specific age, gender and race/ethnicity groups were over...

  19. Examining the Relationship between Math Scores and English Language Proficiency

    ERIC Educational Resources Information Center

    Henry, Denfield L.; Nistor, Nicolae; Baltes, Beate

    2016-01-01

    Multiple studies propose that English proficiency dictates English language learners' (ELLs) performances on mathematics assessments. The current study investigates the predictive power of English proficiency on mathematics scores, while controlling for gender, socioeconomic status (SES), and grade level among ELLs at a south Florida elementary…

  20. Power Maximization Control of Variable Speed Wind Generation System Using Permanent Magnet Synchronous Generator

    NASA Astrophysics Data System (ADS)

    Morimoto, Shigeo; Nakamura, Tomohiko; Takeda, Yoji

    This paper proposes the sensorless output power maximization control of the wind generation system. A permanent magnet synchronous generator (PMSG) is used as a variable speed generator in the proposed system. The generator torque is suitably controlled according to the generator speed and thus the power from a wind turbine settles down on the maximum power point by the proposed MPPT control method, where the information of wind velocity is not required. Moreover, the maximum available generated power is obtained by the optimum current vector control. The current vector of PMSG is optimally controlled according to the generator speed and the required torque in order to minimize the losses of PMSG considering the voltage and current constraints. The proposed wind power generation system can be achieved without mechanical sensors such as a wind velocity detector and a position sensor. Several experimental results show the effectiveness of the proposed control method.

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

    NASA Astrophysics Data System (ADS)

    Tanoi, Satoru; Endoh, Tetsuo

    2012-04-01

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

  2. Final Technical Report Recovery Act: Online Nonintrusive Condition Monitoring and Fault Detection for Wind Turbines

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

    Wei Qiao

    2012-05-29

    The penetration of wind power has increased greatly over the last decade in the United States and across the world. The U.S. wind power industry installed 1,118 MW of new capacity in the first quarter of 2011 alone and entered the second quarter with another 5,600 MW under construction. By 2030, wind energy is expected to provide 20% of the U.S. electricity needs. As the number of wind turbines continues to grow, the need for effective condition monitoring and fault detection (CMFD) systems becomes increasingly important [3]. Online CMFD is an effective means of not only improving the reliability, capacitymore » factor, and lifetime, but it also reduces the downtime, energy loss, and operation and maintenance (O&M) of wind turbines. The goal of this project is to develop novel online nonintrusive CMFD technologies for wind turbines. The proposed technologies use only the current measurements that have been used by the control and protection system of a wind turbine generator (WTG); no additional sensors or data acquisition devices are needed. Current signals are reliable and easily accessible from the ground without intruding on the wind turbine generators (WTGs) that are situated on high towers and installed in remote areas. Therefore, current-based CMFD techniques have great economic benefits and the potential to be adopted by the wind energy industry. Specifically, the following objectives and results have been achieved in this project: (1) Analyzed the effects of faults in a WTG on the generator currents of the WTG operating at variable rotating speed conditions from the perspective of amplitude and frequency modulations of the current measurements; (2) Developed effective amplitude and frequency demodulation methods for appropriate signal conditioning of the current measurements to improve the accuracy and reliability of wind turbine CMFD; (3) Developed a 1P-invariant power spectrum density (PSD) method for effective signature extraction of wind turbine faults with characteristic frequencies in the current or current demodulated signals, where 1P stands for the shaft rotating frequency of a WTG; (4) Developed a wavelet filter for effective signature extraction of wind turbine faults without characteristic frequencies in the current or current demodulated signals; (5) Developed an effective adaptive noise cancellation method as an alternative to the wavelet filter method for signature extraction of wind turbine faults without characteristic frequencies in the current or current demodulated signals; (6) Developed a statistical analysis-based impulse detection method for effective fault signature extraction and evaluation of WTGs based on the 1P-invariant PSD of the current or current demodulated signals; (7) Validated the proposed current-based wind turbine CMFD technologies through extensive computer simulations and experiments for small direct-drive WTGs without gearboxes; and (8) Showed, through extensive experiments for small direct-drive WTGs, that the performance of the proposed current-based wind turbine CMFD technologies is comparable to traditional vibration-based methods. The proposed technologies have been successfully applied for detection of major failures in blades, shafts, bearings, and generators of small direct-drive WTGs. The proposed technologies can be easily integrated into existing wind turbine control, protection, and monitoring systems and can be implemented remotely from the wind turbines being monitored. The proposed technologies provide an alternative to vibration-sensor-based CMFD. This will reduce the cost and hardware complexity of wind turbine CMFD systems. The proposed technologies can also be combined with vibration-sensor-based methods to improve the accuracy and reliability of wind turbine CMFD systems. When there are problems with sensors, the proposed technologies will ensure proper CMFD for the wind turbines, including their sensing systems. In conclusion, the proposed technologies offer an effective means to achieve condition-based smart maintenance for wind turbines and have a great potential to be adopted by the wind energy industry due to their almost no-cost, nonintrusive features. Although only validated for small direct-drive wind turbines without gearboxes, the proposed technologies are also applicable for CMFD of large-size wind turbines with and without gearboxes. However, additional investigations are recommended in order to apply the proposed technologies to those large-size wind turbines.« less

  3. A statistical framework for biomedical literature mining.

    PubMed

    Chung, Dongjun; Lawson, Andrew; Zheng, W Jim

    2017-09-30

    In systems biology, it is of great interest to identify new genes that were not previously reported to be associated with biological pathways related to various functions and diseases. Identification of these new pathway-modulating genes does not only promote understanding of pathway regulation mechanisms but also allow identification of novel targets for therapeutics. Recently, biomedical literature has been considered as a valuable resource to investigate pathway-modulating genes. While the majority of currently available approaches are based on the co-occurrence of genes within an abstract, it has been reported that these approaches show only sub-optimal performances because 70% of abstracts contain information only for a single gene. To overcome such limitation, we propose a novel statistical framework based on the concept of ontology fingerprint that uses gene ontology to extract information from large biomedical literature data. The proposed framework simultaneously identifies pathway-modulating genes and facilitates interpreting functions of these new genes. We also propose a computationally efficient posterior inference procedure based on Metropolis-Hastings within Gibbs sampler for parameter updates and the poor man's reversible jump Markov chain Monte Carlo approach for model selection. We evaluate the proposed statistical framework with simulation studies, experimental validation, and an application to studies of pathway-modulating genes in yeast. The R implementation of the proposed model is currently available at https://dongjunchung.github.io/bayesGO/. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Evolution of Sousa chinensis: a scenario based on mitochondrial DNA study.

    PubMed

    Lin, Wenzhi; Zhou, Ruilian; Porter, Lindsay; Chen, Jialin; Wu, Yuping

    2010-11-01

    Taxonomy within genus Sousa is confused largely due to inconsistencies among external morphology, skull morphology, pigmentation patterns and molecular studies. Here we provide our understanding of the evolution of Sousa chinensis by proposing a phylogeographic history based on mtDNA study. It is proposed that the species originated in eastern Australian waters and the current distribution has taken shape over the last 8.02-1.24 million years. Populations in Southeast Asia and Australian region experienced recent expansion about 0.54-1.5 million years ago. It is also proposed that populations in Southeast Asia experienced separation, re-unification and further dispersal during the last glacial age with multiple north-south migration across the Sahul Shelf area of northern Australia. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Future Directions for Business Education: A Delphi Study

    ERIC Educational Resources Information Center

    Kesten, Cyril A.; Lambrecht, Judith J.

    2010-01-01

    Purpose: The purpose of this study was to synthesize perceptions from the field about current issues and to propose future directions for the field of business education. Method: A modified three-stage Delphi study was carried out with business educators who attended national conferences and/or belonged to national professional organizations.…

  6. 77 FR 31027 - Submission for OMB Review; Comment Request; Web-Based Assessment of the Clinical Studies Support...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ...; Comment Request; Web-Based Assessment of the Clinical Studies Support Center (CSSC) Summary: Under the... current valid OMB control number. Proposed Collection: Title: Web-Based Assessment of the Clinical Studies... Operations and Procedures (MOP); coordinating meeting space and logistics for in-person meetings, Web...

  7. Predicting Acceptance of Mobile Technology for Aiding Student-Lecturer Interactions: An Empirical Study

    ERIC Educational Resources Information Center

    Gan, Chin Lay; Balakrishnan, Vimala

    2017-01-01

    The current study sets out to identify determinants affecting tertiary students' behavioural intentions to use mobile technology in lectures. The study emphasises that the reason for using mobile technology in classrooms with large numbers of students is to facilitate interactions among students and lecturers. The proposed conceptual framework has…

  8. How much can a large population study on genes, environments, their interactions and common diseases contribute to the health of the American people?

    PubMed

    Chaufan, Claudia

    2007-10-01

    I offer a critical perspective on a large-scale population study on gene-environment interactions and common diseases proposed by the US Secretary of Health and Human Services' Advisory Committee on Genetics, Health, and Society (SACGHS). I argue that for scientific and policy reasons this and similar studies have little to add to current knowledge about how to prevent, treat, or decrease inequalities in common diseases, all of which are major claims of the proposal. I use diabetes as an exemplar of the diseases that the study purports to illuminate. I conclude that the question is not whether the study will meet expectations or whether the current emphasis on a genetic paradigm is real or imagined, desirable or not. Rather, the question is why, given the flaws of the science underwriting the study, its assumptions remain unchallenged. Future research should investigate the reasons for this immunity from criticism and for the popularity of this and similar projects among laypersons as well as among intellectuals.

  9. Chinese Space Program for Heliophysics

    NASA Astrophysics Data System (ADS)

    Wu, Ji; Gan, Weiqun; Wang, Chi; Liu, Weining; Yan, Yihua; Liu, Yong; Sun, Lilin; Liu, Ying

    As one of the major field of space science, heliophysics research in China has not only long history but also strong research forces. Many space missions have been proposed by the community but with few got support. Since 2006, Chinese Academy of Science has organized a long term strategic study in space science. In 2011, the space science program has been kicked off with several new missions being selected for Phase A study. In this presentation, first a brief review on past programs, such as Double Star, Chang’e, and an introduction on the space science strategic study are given. Under the guidance of this strategic study or roadmap, a few missions have been proposed or re-proposed with new element, such as DSO, KUAFU, MIT, SPORT and ASO-S. Brief introductions of these programs and their current status will be given.

  10. The next GUM and its proposals: a comparison study

    NASA Astrophysics Data System (ADS)

    Damasceno, J. C.; Couto, P. R. G.

    2018-03-01

    The Guide to the Expression of Uncertainty in Measurement (GUM) is currently under revision. New proposals for its implementation were circulated in the form of a draft document. Two of the main changes are explored in this work using a Brinell hardness model example. Changes in the evaluation of uncertainty for repeated indications and in the construction of coverage intervals are compared with the classic GUM and with Monte Carlo simulation method.

  11. 76 FR 20346 - Meeting of the Chief of Naval Operations Executive Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ... Operations (CNO) Executive Panel will deliberate on the findings and proposed recommendations of the Agile IT Subcommittee study. The meeting will consist of discussions of current and future Navy strategy and plans in...

  12. Gender profiling: a gendered race perspective on person-position fit.

    PubMed

    Hall, Erika V; Galinsky, Adam D; Phillips, Katherine W

    2015-06-01

    The current research integrates perspectives on gendered race and person-position fit to introduce the concept of a gender profile. We propose that both the "gender" of a person's biological sex and the "gender" of a person's race (Asians are perceived as feminine and Blacks as masculine) help comprise an individual's gender profile-the overall femininity or masculinity associated with their demographic characteristics. We also propose that occupational positions have gender profiles. Finally, we argue that the overall gender profile of one's demographics, rather than just one's biological sex, determines one's fit and hirability for feminine or masculine occupational roles. The current five studies establish the gender profiles of different races and sexes, and then demonstrate that individuals with feminine-typed and masculine-typed gender profiles are selected for feminine and masculine positions, respectively. These studies provide new insights on who gets ahead in different environments. © 2015 by the Society for Personality and Social Psychology, Inc.

  13. In search of mixed anxiety-depressive disorder: a primary care study.

    PubMed

    Means-Christensen, Adrienne J; Sherbourne, Cathy D; Roy-Byrne, Peter P; Schulman, Martin C; Wu, Jennifer; Dugdale, David C; Lessler, Daniel; Stein, Murray B

    2006-01-01

    The diagnosis of mixed anxiety-depressive disorder, as proposed in DSM-IV, is intended to be useful in settings such as primary care, where low-level anxiety and depressive symptoms may cause clinically significant impairment but are undiagnosable using current criteria. Evidence of the prevalence of this diagnosis is, however, lacking, particularly since the publication of the proposed diagnostic criteria in DSM-IV. Our study examined symptoms of anxiety and depression in 65 primary care patients screened for anxiety and depression while visiting their doctor. Results indicated that of the 37 patients without a diagnosable anxiety or depressive disorder, none had symptoms of depression and anxiety accompanied by interference that the patient deemed significant and attributable to his or her symptoms. These data dispute the need for a mixed anxiety-depression category (beyond mood and anxiety syndromes currently in DSM-IV) in future editions of the DSM.

  14. A Solid-State Fault Current Limiting Device for VSC-HVDC Systems

    NASA Astrophysics Data System (ADS)

    Larruskain, D. Marene; Zamora, Inmaculada; Abarrategui, , Oihane; Iturregi, Araitz

    2013-08-01

    Faults in the DC circuit constitute one of the main limitations of voltage source converter VSC-HVDC systems, as the high fault currents can damage seriously the converters. In this article, a new design for a fault current limiter (FCL) is proposed, which is capable of limiting the fault current as well as interrupting it, isolating the DC grid. The operation of the proposed FCL is analysed and verified with the most usual faults that can occur in overhead lines.

  15. Current and future graphics requirements for LaRC and proposed future graphics system

    NASA Technical Reports Server (NTRS)

    Taylor, N. L.; Bowen, J. T.; Randall, D. P.; Gates, R. L.

    1984-01-01

    The findings of an investigation to assess the current and future graphics requirements of the LaRC researchers with respect to both hardware and software are presented. A graphics system designed to meet these requirements is proposed.

  16. Evaluating the impacts of proposed speed limit increases in Michigan : research spotlight.

    DOT National Transportation Integrated Search

    2014-07-01

    Recent proposed speed limit legislation led MDOT to evaluate the : states current speed limit policies and potential alternatives. Currently, : Michigan freeways have a maximum speed limit of 70 mph for passenger : vehicles and 60 mph for trucks a...

  17. 75 FR 22577 - Proposed Rule of Agency Procedure No. 1: Procedures for Voting by Circulation Version 2.0

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-29

    ... deadlines, the current policy limits EAC's ability to address the rare situations that require swift action... Procedure No. 1: Procedures for Voting by Circulation Version 2.0. EAC's current Proposed Rule of Agency...

  18. 76 FR 64975 - Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-19

    ... examine in detail the nature of various employment and unemployment situations. II. Current Action Office... comments concerning the proposed new collection of the ``Current Population Survey (CPS) Disability... conducted at the request of the Department of Labor's Office of Disability Employment Policy. The Disability...

  19. Apparent isotropic electrical property for electrical brain stimulation (EBS) using magnetic resonance diffusion weighted imaging (MR-DWI)

    NASA Astrophysics Data System (ADS)

    Lee, Mun Bae; Kwon, Oh-In

    2018-04-01

    Electrical brain stimulation (EBS) is an invasive electrotherapy and technique used in brain neurological disorders through direct or indirect stimulation using a small electric current. EBS has relied on computational modeling to achieve optimal stimulation effects and investigate the internal activations. Magnetic resonance diffusion weighted imaging (DWI) is commonly useful for diagnosis and investigation of tissue functions in various organs. The apparent diffusion coefficient (ADC) measures the intensity of water diffusion within biological tissues using DWI. By measuring trace ADC and magnetic flux density induced by the EBS, we propose a method to extract electrical properties including the effective extracellular ion-concentration (EEIC) and the apparent isotropic conductivity without any auxiliary additional current injection. First, the internal current density due to EBS is recovered using the measured one component of magnetic flux density. We update the EEIC by introducing a repetitive scheme called the diffusion weighting J-substitution algorithm using the recovered current density and the trace ADC. To verify the proposed method, we study an anesthetized canine brain to visualize electrical properties including electrical current density, effective extracellular ion-concentration, and effective isotropic conductivity by applying electrical stimulation of the brain.

  20. Time Requirements for the Different Item Types Proposed for Use in the Revised SAT®. Research Report No. 2007-3. ETS RR-07-35

    ERIC Educational Resources Information Center

    Bridgeman, Brent; Laitusis, Cara Cahalan; Cline, Frederick

    2007-01-01

    The current study used three data sources to estimate time requirements for different item types on the now current SAT Reasoning Test™. First, we estimated times from a computer-adaptive version of the SAT® (SAT CAT) that automatically recorded item times. Second, we observed students as they answered SAT questions under strict time limits and…

  1. Hierarchical Bayesian Models of Subtask Learning

    ERIC Educational Resources Information Center

    Anglim, Jeromy; Wynton, Sarah K. A.

    2015-01-01

    The current study used Bayesian hierarchical methods to challenge and extend previous work on subtask learning consistency. A general model of individual-level subtask learning was proposed focusing on power and exponential functions with constraints to test for inconsistency. To study subtask learning, we developed a novel computer-based booking…

  2. Reading Meta-Television: A New Model for Reader-Response Criticism.

    ERIC Educational Resources Information Center

    Olson, Scott R.

    Many current models of television viewing regard viewers either as passive receptors, active participants, or addled dupes. A study proposed a more flexible model for television viewing research. The study used the television program "St. Elsewhere," an example of "meta-television" (television programming which contains hidden…

  3. Risk Perception in Smokers with Children with Asthma

    ERIC Educational Resources Information Center

    Wagener, Theodore L.; Gregor, Kristin L.; Busch, Andrew M.; McQuaid, Elizabeth L.; Borrelli, Belinda

    2010-01-01

    Objective: No studies have examined the relationship between caregiver beliefs about the risks of smoking to their own health and caregiver beliefs about the effect of their smoking on their child's health. In the current study, we investigated our proposed "risk congruence hypothesis" among caregivers who smoke. Specifically, we investigated…

  4. 76 FR 26303 - Proposed Information Collection Activity; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-06

    ... Impact Study. OMB No.: 0970-0229. Description: The Administration for Children and Families (ACF) of the... children and families in the Head Start Impact Study. In anticipation of the possibility of conducting a... respondents' current location, as well as other basic information about the parents' whereabouts and future...

  5. A Generalized Precharging Strategy for Soft Startup Process of the Modular Multilevel Converter-Based HVDC Systems

    DOE PAGES

    Zhang, Lei; Qin, Jiangchao; Wu, Xiajie; ...

    2017-01-01

    The modular multilevel converter (MMC) has become one of the most promising converter technologies for medium/high-power applications, specifically for highvoltage direct current (HVDC) transmission systems. One of the technical challenges associated with the operation and control of the MMC-based system is to precharge the submodule (SM) capacitors to their nominal voltage during the startup process. In this paper, considering various SM circuits, a generalized precharging strategy is proposed for the MMC-based systems, which can implement soft stratup from dc or ac side. Furthermore, the proposed precharging strategy can be applicabe for various SM circuits and MMC configurations. The proposed startupmore » strategy does not require extra measurements and/or auxiliary power supplies. The charging current is controlled by adjusting the changing rate of the number of blocked and bypassed SM capacitors. Based on the proposed startup strategy, the startup processes of MMC/MMC-HVDC systems based on various SM circuits are analyzed and a generalized startup procedure for various MMC-HVDC systems is proposed. In addition, the uncontrollable steady-state SM capacitor voltages of various MMC-based systems are analyzed and determined, potentially useful in SM design. Our performance of the proposed strategy for various MMC-HVDC systems is evaluated based on time-domain simulation studies in the PSCAD/EMTDC software environment and experimental results based on a scaled-down prototype.« less

  6. A Generalized Precharging Strategy for Soft Startup Process of the Modular Multilevel Converter-Based HVDC Systems

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

    Zhang, Lei; Qin, Jiangchao; Wu, Xiajie

    The modular multilevel converter (MMC) has become one of the most promising converter technologies for medium/high-power applications, specifically for highvoltage direct current (HVDC) transmission systems. One of the technical challenges associated with the operation and control of the MMC-based system is to precharge the submodule (SM) capacitors to their nominal voltage during the startup process. In this paper, considering various SM circuits, a generalized precharging strategy is proposed for the MMC-based systems, which can implement soft stratup from dc or ac side. Furthermore, the proposed precharging strategy can be applicabe for various SM circuits and MMC configurations. The proposed startupmore » strategy does not require extra measurements and/or auxiliary power supplies. The charging current is controlled by adjusting the changing rate of the number of blocked and bypassed SM capacitors. Based on the proposed startup strategy, the startup processes of MMC/MMC-HVDC systems based on various SM circuits are analyzed and a generalized startup procedure for various MMC-HVDC systems is proposed. In addition, the uncontrollable steady-state SM capacitor voltages of various MMC-based systems are analyzed and determined, potentially useful in SM design. Our performance of the proposed strategy for various MMC-HVDC systems is evaluated based on time-domain simulation studies in the PSCAD/EMTDC software environment and experimental results based on a scaled-down prototype.« less

  7. A dual-loop adaptive control for minimizing time response delay in real-time structural vibration control with magnetorheological (MR) devices

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Li, Yancheng; Li, Jianchun; Gu, Xiaoyu

    2018-01-01

    Time delay is a challenge issue faced by the real-time control application of the magnetorheological (MR) devices. Not to deal with it properly may jeopardize the effectiveness of the control, even lead to instability of the control system or catastrophic failure. This paper proposes a dual-loop adaptive control to address the response time delay associated with MR devices. In the proposed dual-loop control, the inner loop is designed to compensate the time delay of MR device induced by the PWM current driver. While the outer loop control can be any structural control algorithm with aims to reducing structural responses of a building during extreme loadings. Here an adaptive control strategy is adopted. To verify the proposed dual-loop control, a smart base isolation system employing magnetorheological elastomer base isolators is used as an example to illustrate the control effect. Numerical study is then conducted using a 5 -storey shear building model equipped with smart base isolation system. The result shows that with the implementation of the inner loop, the control current can instantly follow the control command which reduce the possibility of instability caused by the time delay. Comparative studies are conducted between three control strategies, i.e. dual-loop control, Lyapunov’s direct method based control and optimal passive base isolation control. The results of the study have demonstrated that the proposed dual-loop control strategy can achieve much better performance than the other two control strategies.

  8. Study on the steady operating state of a micro-pulse electron gun

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

    Kui, Zhou; Xing, Luo; Institute of Applied Electronics, Chinese Academy of Engineering Physics, Mianyang 621900

    Micro-pulse electron gun (MPG) employs the basic concept of multipacting to produce high-current and short-pulse electron beams from a radio-frequency (RF) cavity. The concept of MPG has been proposed for more than two decades. However, the unstable operating state of MPG vastly obstructs its practical applications. This paper presents a study on the steady operating state of a micro-pulse electron gun with theory and experiments. The requirements for the steady operating state are proposed through the analysis of the interaction between the RF cavity and the beam load. Accordingly, a MPG cavity with the frequency of 2856 MHz has been designed,more » constructed, and tested. Some primary experiments have been finished. Both the unstable and stable operating states of the MPG have been observed. The stable output beam current has been detected at about 3.8 mA. Further experimental study is under way now.« less

  9. Investigation of the residue in an electric rail gun employing a plasma armature

    NASA Technical Reports Server (NTRS)

    Bauer, D. P.; Barber, J. P.

    1984-01-01

    The performance of dc electric rail guns using plasma-armature-accelerated projectiles was studied. It was found that the initial rail launcher acceleration profile was consistent with the simulation, but that after the projectile had traveled approximately 25 to 30 cm along the gun, a considerable portion of the current in the projectile armature commutated into a secondary current path. Also noted were the lower than expected muzzle velocities. It was proposed that the secondary current path was a relatively high conductivity layer of residue on the launcher bore.

  10. A Study of the Implementation of Current Cost Accounting in the Republic of Korea Army Procurement Systems.

    DTIC Science & Technology

    1986-06-01

    financial reporting in Republic of Korea Army (ROKA) procurement. A discussion of the nature of the ROKA procurement system and two alternatives to historical cost financial statements are presented. The concepts, methods and procedures of the historical cost/constant dollars financial statements are described. The proposal for current cost/constant dollars financial statements is presented and emphasis is given to the description of four problems in existing ROKA procurement due to using inadequate accounting information. Keywords: Cost accounting, Procurement, Current

  11. Sensorless Sinusoidal Drives for Fan and Pump Motors by V/f Control

    NASA Astrophysics Data System (ADS)

    Kiuchi, Mitsuyuki; Ohnishi, Tokuo

    This paper proposes sensorless sinusoidal driving methods of permanent magnet synchronous motors for fans and pumps by V/f control. The proposed methods are simple methods that control the motor peak current constant by voltage or frequency control, and are characterized by DC link current detection using a single shunt resistor at carrier wave signal bottom timing. As a result of the dumping factor from square torque load characteristics of fan and pump motors, it is possible to control stable starting and stable steady state by V/f control. In general, pressure losses as a result of the fluid pass of fan and pump systems are nearly constant; therefore, the flow rate and motor torque are determined by revolutions. Accordingly, high efficiency driving is possible by setting corresponding currents to q-axis currents (torque currents) at target revolutions. Because of the simple current detection and motor control methods, the proposed methods are optimum for fan and pump motor driving systems of home appliances.

  12. Self-consistent current sheet structures in the quiet-time magnetotail

    NASA Technical Reports Server (NTRS)

    Holland, Daniel L.; Chen, James

    1993-01-01

    The structure of the quiet-time magnetotail is studied using a test particle simulation. Vlasov equilibria are obtained in the regime where v(D) = E(y) c/B(z) is much less than the ion thermal velocity and are self-consistent in that the current and magnetic field satisfy Ampere's law. Force balance between the plasma and magnetic field is satisfied everywhere. The global structure of the current sheet is found to be critically dependent on the source distribution function. The pressure tensor is nondiagonal in the current sheet with anisotropic temperature. A kinetic mechanism is proposed whereby changes in the source distribution results in a thinning of the current sheet.

  13. 76 FR 3610 - Proposed Information Collection; Comment Request; Current Population Surveys (CPS)-Housing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-20

    ... DEPARTMENT OF COMMERCE U.S. Census Bureau Proposed Information Collection; Comment Request; Current Population Surveys (CPS)--Housing Vacancy Survey (HVS) AGENCY: U.S. Census Bureau, Commerce. ACTION: Notice. SUMMARY: The Department of Commerce, as part of its continuing [[Page 3611

  14. An Improved Distributed Secondary Control Method for DC Microgrids With Enhanced Dynamic Current Sharing Performance

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

    Wang, Panbao; Lu, Xiaonan; Yang, Xu

    This paper proposes an improved distributed secondary control scheme for dc microgrids (MGs), aiming at overcoming the drawbacks of conventional droop control method. The proposed secondary control scheme can remove the dc voltage deviation and improve the current sharing accuracy by using voltage-shifting and slope-adjusting approaches simultaneously. Meanwhile, the average value of droop coefficients is calculated, and then it is controlled by an additional controller included in the distributed secondary control layer to ensure that each droop coefficient converges at a reasonable value. Hence, by adjusting the droop coefficient, each participating converter has equal output impedance, and the accurate proportionalmore » load current sharing can be achieved with different line resistances. Furthermore, the current sharing performance in steady and transient states can be enhanced by using the proposed method. The effectiveness of the proposed method is verified by detailed experimental tests based on a 3 × 1 kW prototype with three interface converters.« less

  15. Field programmable analog array based on current differencing transconductance amplifiers and its application to high-order filter

    NASA Astrophysics Data System (ADS)

    He, Haizhen; Luo, Rongming; Hu, Zhenhua; Wen, Lei

    2017-07-01

    A current-mode field programmable analog array(FPAA) is presented in this paper. The proposed FPAA consists of 9 configurable analog blocks(CABs) which are based on current differencing transconductance amplifiers (CDTA) and trans-impedance amplifier (TIA). The proposed CABs interconnect through global lines. These global lines contain some bridge switches, which used to reduce the parasitic capacitance effectively. High-order current-mode low-pass and band-pass filter with transmission zeros based on the simulation of general passive RLC ladder prototypes is proposed and mapped into the FPAA structure in order to demonstrate the versatility of the FPAA. These filters exhibit good performance on bandwidth. Filter's cutoff frequency can be tuned from 1.2MHz to 40MHz.The proposed FPAA is simulated in a standard Charted 0.18μm CMOS process with +/-1.2V power supply to confirm the presented theory, and the results have good agreement with the theoretical analysis.

  16. A Robust High-Performance GPS L1 Receiver with Single-stage Quadrature Redio-Frequency Circuit

    NASA Astrophysics Data System (ADS)

    Liu, Jianghua; Xu, Weilin; Wan, Qinq; Liu, Tianci

    2018-03-01

    A low power current reuse single-stage quadrature raido-frequency part (SQRF) is proposed for GPS L1 receiver in 180nm CMOS process. The proposed circuit consists of LNA, Mixer, QVCO, is called the QLMV cell. A two blocks stacked topology is adopted in this design. The parallel QVCO and mixer placed on the top forms the upper stacked block, and the LNA placed on the bottom forms the other stacked block. The two blocks share the current and achieve low power performance. To improve the stability, a float current source is proposed. The float current isolated the local oscillation signal and the input RF signal, which bring the whole circuit robust high-performance. The result shows conversion gain is 34 dB, noise figure is three dB, the phase noise is -110 dBc/Hz at 1MHz and IIP3 is -20 dBm. The proposed circuit dissipated 1.7mW with 1 V supply voltage.

  17. An omnipotent Li-ion battery charger with multimode control and polarity reversible techniques

    NASA Astrophysics Data System (ADS)

    Chen, Jiann-Jong; Ku, Yi-Tsen; Yang, Hong-Yi; Hwang, Yuh-Shyan; Yu, Cheng-Chieh

    2016-07-01

    The omnipotent Li-ion battery charger with multimode control and polarity reversible techniques is presented in this article. The proposed chip is fabricated with TSMC 0.35μm 2P4M complementary metal-oxide- semiconductor processes, and the chip area including pads is 1.5 × 1.5 mm2. The structure of the omnipotent charger combines three charging modes and polarity reversible techniques, which adapt to any Li-ion batteries. The three reversible Li-ion battery charging modes, including trickle-current charging, large-current charging and constant-voltage charging, can charge in matching polarities or opposite polarities. The proposed circuit has a maximum charging current of 300 mA and the input voltage of the proposed circuit is set to 4.5 V. The maximum efficiency of the proposed charger is about 91% and its average efficiency is 74.8%. The omnipotent charger can precisely provide the charging current to the battery.

  18. Frequentist Model Averaging in Structural Equation Modelling.

    PubMed

    Jin, Shaobo; Ankargren, Sebastian

    2018-06-04

    Model selection from a set of candidate models plays an important role in many structural equation modelling applications. However, traditional model selection methods introduce extra randomness that is not accounted for by post-model selection inference. In the current study, we propose a model averaging technique within the frequentist statistical framework. Instead of selecting an optimal model, the contributions of all candidate models are acknowledged. Valid confidence intervals and a [Formula: see text] test statistic are proposed. A simulation study shows that the proposed method is able to produce a robust mean-squared error, a better coverage probability, and a better goodness-of-fit test compared to model selection. It is an interesting compromise between model selection and the full model.

  19. To Control False Positives in Gene-Gene Interaction Analysis: Two Novel Conditional Entropy-Based Approaches

    PubMed Central

    Lin, Meihua; Li, Haoli; Zhao, Xiaolei; Qin, Jiheng

    2013-01-01

    Genome-wide analysis of gene-gene interactions has been recognized as a powerful avenue to identify the missing genetic components that can not be detected by using current single-point association analysis. Recently, several model-free methods (e.g. the commonly used information based metrics and several logistic regression-based metrics) were developed for detecting non-linear dependence between genetic loci, but they are potentially at the risk of inflated false positive error, in particular when the main effects at one or both loci are salient. In this study, we proposed two conditional entropy-based metrics to challenge this limitation. Extensive simulations demonstrated that the two proposed metrics, provided the disease is rare, could maintain consistently correct false positive rate. In the scenarios for a common disease, our proposed metrics achieved better or comparable control of false positive error, compared to four previously proposed model-free metrics. In terms of power, our methods outperformed several competing metrics in a range of common disease models. Furthermore, in real data analyses, both metrics succeeded in detecting interactions and were competitive with the originally reported results or the logistic regression approaches. In conclusion, the proposed conditional entropy-based metrics are promising as alternatives to current model-based approaches for detecting genuine epistatic effects. PMID:24339984

  20. 76 FR 213 - National Environmental Policy Act Implementing Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ...The U.S. Department of Energy (DOE or the Department) proposes to amend its existing regulations governing compliance with the National Environmental Policy Act (NEPA). The majority of the changes are proposed for the categorical exclusions provisions contained in its NEPA Implementing Procedures, with a small number of related changes proposed for other provisions. These proposed changes are intended to better align the Department's regulations, particularly its categorical exclusions, with DOE's current activities and recent experiences, and to update the provisions with respect to current technologies and regulatory requirements. DOE proposes to establish 20 new categorical exclusions, and to remove two categorical exclusion categories, one environmental assessment (EA) category, and two environmental impact statement (EIS) categories. Other proposed changes modify and clarify DOE's existing provisions.

  1. Impacts of pending federal greenhouse gas legislation on the Texas transportation sector.

    DOT National Transportation Integrated Search

    2010-05-01

    This 2010 study, funded by the Southwest Region University Transportation Center, assesses current regulatory : attempts to mitigate climate change and how such proposed action would impact the Texas transportation sector : economically. Social and p...

  2. Short-Wavelength Light-Emitting Devices With Enhanced Hole Injection Currents

    DTIC Science & Technology

    2005-05-01

    hot-hole injector with appreciably enhancement of the injection current is proposed and developed to be integrated with commonly used vertical...structures of the emitting devices. Second, we develop the alternative design of UV-light sources on the base of lateral p+ - i - n+ superlattice structures...enhancement of the injection current is proposed and developed to be integrated with commonly used vertical structures of the emitting devices. Second

  3. Towards Real-Time Detection of Gait Events on Different Terrains Using Time-Frequency Analysis and Peak Heuristics Algorithm.

    PubMed

    Zhou, Hui; Ji, Ning; Samuel, Oluwarotimi Williams; Cao, Yafei; Zhao, Zheyi; Chen, Shixiong; Li, Guanglin

    2016-10-01

    Real-time detection of gait events can be applied as a reliable input to control drop foot correction devices and lower-limb prostheses. Among the different sensors used to acquire the signals associated with walking for gait event detection, the accelerometer is considered as a preferable sensor due to its convenience of use, small size, low cost, reliability, and low power consumption. Based on the acceleration signals, different algorithms have been proposed to detect toe off (TO) and heel strike (HS) gait events in previous studies. While these algorithms could achieve a relatively reasonable performance in gait event detection, they suffer from limitations such as poor real-time performance and are less reliable in the cases of up stair and down stair terrains. In this study, a new algorithm is proposed to detect the gait events on three walking terrains in real-time based on the analysis of acceleration jerk signals with a time-frequency method to obtain gait parameters, and then the determination of the peaks of jerk signals using peak heuristics. The performance of the newly proposed algorithm was evaluated with eight healthy subjects when they were walking on level ground, up stairs, and down stairs. Our experimental results showed that the mean F1 scores of the proposed algorithm were above 0.98 for HS event detection and 0.95 for TO event detection on the three terrains. This indicates that the current algorithm would be robust and accurate for gait event detection on different terrains. Findings from the current study suggest that the proposed method may be a preferable option in some applications such as drop foot correction devices and leg prostheses.

  4. Towards Real-Time Detection of Gait Events on Different Terrains Using Time-Frequency Analysis and Peak Heuristics Algorithm

    PubMed Central

    Zhou, Hui; Ji, Ning; Samuel, Oluwarotimi Williams; Cao, Yafei; Zhao, Zheyi; Chen, Shixiong; Li, Guanglin

    2016-01-01

    Real-time detection of gait events can be applied as a reliable input to control drop foot correction devices and lower-limb prostheses. Among the different sensors used to acquire the signals associated with walking for gait event detection, the accelerometer is considered as a preferable sensor due to its convenience of use, small size, low cost, reliability, and low power consumption. Based on the acceleration signals, different algorithms have been proposed to detect toe off (TO) and heel strike (HS) gait events in previous studies. While these algorithms could achieve a relatively reasonable performance in gait event detection, they suffer from limitations such as poor real-time performance and are less reliable in the cases of up stair and down stair terrains. In this study, a new algorithm is proposed to detect the gait events on three walking terrains in real-time based on the analysis of acceleration jerk signals with a time-frequency method to obtain gait parameters, and then the determination of the peaks of jerk signals using peak heuristics. The performance of the newly proposed algorithm was evaluated with eight healthy subjects when they were walking on level ground, up stairs, and down stairs. Our experimental results showed that the mean F1 scores of the proposed algorithm were above 0.98 for HS event detection and 0.95 for TO event detection on the three terrains. This indicates that the current algorithm would be robust and accurate for gait event detection on different terrains. Findings from the current study suggest that the proposed method may be a preferable option in some applications such as drop foot correction devices and leg prostheses. PMID:27706086

  5. Classification of physical activities based on body-segments coordination.

    PubMed

    Fradet, Laetitia; Marin, Frederic

    2016-09-01

    Numerous innovations based on connected objects and physical activity (PA) monitoring have been proposed. However, recognition of PAs requires robust algorithm and methodology. The current study presents an innovative approach for PA recognition. It is based on the heuristic definition of postures and the use of body-segments coordination obtained through external sensors. The first part of this study presents the methodology required to define the set of accelerations which is the most appropriate to represent the particular body-segments coordination involved in the chosen PAs (here walking, running, and cycling). For that purpose, subjects of different ages and heterogeneous physical conditions walked, ran, cycled, and performed daily activities at different paces. From the 3D motion capture, vertical and horizontal accelerations of 8 anatomical landmarks representative of the body were computed. Then, the 680 combinations from up to 3 accelerations were compared to identify the most appropriate set of acceleration to discriminate the PAs in terms of body segment coordinations. The discrimination was based on the maximal Hausdorff Distance obtained between the different set of accelerations. The vertical accelerations of both knees demonstrated the best PAs discrimination. The second step was the proof of concept, implementing the proposed algorithm to classify PAs of new group of subjects. The originality of the proposed algorithm is the possibility to use the subject's specific measures as reference data. With the proposed algorithm, 94% of the trials were correctly classified. In conclusion, our study proposed a flexible and extendable methodology. At the current stage, the algorithm has been shown to be valid for heterogeneous subjects, which suggests that it could be deployed in clinical or health-related applications regardless of the subjects' physical abilities or characteristics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Classification of Parkinson's disease utilizing multi-edit nearest-neighbor and ensemble learning algorithms with speech samples.

    PubMed

    Zhang, He-Hua; Yang, Liuyang; Liu, Yuchuan; Wang, Pin; Yin, Jun; Li, Yongming; Qiu, Mingguo; Zhu, Xueru; Yan, Fang

    2016-11-16

    The use of speech based data in the classification of Parkinson disease (PD) has been shown to provide an effect, non-invasive mode of classification in recent years. Thus, there has been an increased interest in speech pattern analysis methods applicable to Parkinsonism for building predictive tele-diagnosis and tele-monitoring models. One of the obstacles in optimizing classifications is to reduce noise within the collected speech samples, thus ensuring better classification accuracy and stability. While the currently used methods are effect, the ability to invoke instance selection has been seldomly examined. In this study, a PD classification algorithm was proposed and examined that combines a multi-edit-nearest-neighbor (MENN) algorithm and an ensemble learning algorithm. First, the MENN algorithm is applied for selecting optimal training speech samples iteratively, thereby obtaining samples with high separability. Next, an ensemble learning algorithm, random forest (RF) or decorrelated neural network ensembles (DNNE), is used to generate trained samples from the collected training samples. Lastly, the trained ensemble learning algorithms are applied to the test samples for PD classification. This proposed method was examined using a more recently deposited public datasets and compared against other currently used algorithms for validation. Experimental results showed that the proposed algorithm obtained the highest degree of improved classification accuracy (29.44%) compared with the other algorithm that was examined. Furthermore, the MENN algorithm alone was found to improve classification accuracy by as much as 45.72%. Moreover, the proposed algorithm was found to exhibit a higher stability, particularly when combining the MENN and RF algorithms. This study showed that the proposed method could improve PD classification when using speech data and can be applied to future studies seeking to improve PD classification methods.

  7. Current food classifications in epidemiological studies do not enable solid nutritional recommendations for preventing diet-related chronic diseases: the impact of food processing.

    PubMed

    Fardet, Anthony; Rock, Edmond; Bassama, Joseph; Bohuon, Philippe; Prabhasankar, Pichan; Monteiro, Carlos; Moubarac, Jean-Claude; Achir, Nawel

    2015-11-01

    To date, observational studies in nutrition have categorized foods into groups such as dairy, cereals, fruits, and vegetables. However, the strength of the association between food groups and chronic diseases is far from convincing. In most international expert surveys, risks are most commonly scored as probable, limited, or insufficient rather than convincing. In this position paper, we hypothesize that current food classifications based on botanical or animal origins can be improved to yield solid recommendations. We propose using a food classification that employs food processes to rank foods in epidemiological studies. Indeed, food health potential results from both nutrient density and food structure (i.e., the matrix effect), both of which can potentially be positively or negatively modified by processing. For example, cereal-based foods may be more or less refined, fractionated, and recombined with added salt, sugars, and fats, yielding a panoply of products with very different nutritional values. The same is true for other food groups. Finally, we propose that from a nutritional perspective, food processing will be an important issue to consider in the coming years, particularly in terms of strengthening the links between food and health and for proposing improved nutritional recommendations or actions. © 2015 American Society for Nutrition.

  8. The Hippocampus Supports High-Resolution Binding in the Service of Perception, Working Memory and Long-Term Memory

    PubMed Central

    Yonelinas, Andrew P.

    2013-01-01

    It is well established that the hippocampus plays a critical role in our ability to recollect past events. A number of recent studies have indicated that the hippocampus may also play a critical role in working memory and perception, but these results have been highly controversial because other similar studies have failed to find evidence for hippocampal involvement. Thus, the precise role that the hippocampus plays in cognition is still debated. In the current paper, I propose that the hippocampus supports the generation and utilization of complex high-resolution bindings that link together the qualitative aspects that make up an event; these bindings are essential for recollection, and they can also contribute to performance across a variety of tasks including perception and working memory. An examination of the existing patient literature provides support for this proposal by showing that hippocampal damage leads to impairments on perception and working memory tasks that require complex high-resolution bindings. Conversely, hippocampal damage is much less likely to lead to impairments on tasks that require only low-resolution or simple associations/relations. The current proposal can be distinguished from earlier accounts of hippocampal function, and it generates a number of novel predictions that can be tested in future studies. PMID:23721964

  9. Current Food Classifications in Epidemiological Studies Do Not Enable Solid Nutritional Recommendations for Preventing Diet-Related Chronic Diseases: The Impact of Food Processing12

    PubMed Central

    Fardet, Anthony; Rock, Edmond; Bassama, Joseph; Bohuon, Philippe; Prabhasankar, Pichan; Monteiro, Carlos; Moubarac, Jean-Claude; Achir, Nawel

    2015-01-01

    To date, observational studies in nutrition have categorized foods into groups such as dairy, cereals, fruits, and vegetables. However, the strength of the association between food groups and chronic diseases is far from convincing. In most international expert surveys, risks are most commonly scored as probable, limited, or insufficient rather than convincing. In this position paper, we hypothesize that current food classifications based on botanical or animal origins can be improved to yield solid recommendations. We propose using a food classification that employs food processes to rank foods in epidemiological studies. Indeed, food health potential results from both nutrient density and food structure (i.e., the matrix effect), both of which can potentially be positively or negatively modified by processing. For example, cereal-based foods may be more or less refined, fractionated, and recombined with added salt, sugars, and fats, yielding a panoply of products with very different nutritional values. The same is true for other food groups. Finally, we propose that from a nutritional perspective, food processing will be an important issue to consider in the coming years, particularly in terms of strengthening the links between food and health and for proposing improved nutritional recommendations or actions. PMID:26567188

  10. An Optimization System with Parallel Processing for Reducing Common-Mode Current on Electronic Control Unit

    NASA Astrophysics Data System (ADS)

    Okazaki, Yuji; Uno, Takanori; Asai, Hideki

    In this paper, we propose an optimization system with parallel processing for reducing electromagnetic interference (EMI) on electronic control unit (ECU). We adopt simulated annealing (SA), genetic algorithm (GA) and taboo search (TS) to seek optimal solutions, and a Spice-like circuit simulator to analyze common-mode current. Therefore, the proposed system can determine the adequate combinations of the parasitic inductance and capacitance values on printed circuit board (PCB) efficiently and practically, to reduce EMI caused by the common-mode current. Finally, we apply the proposed system to an example circuit to verify the validity and efficiency of the system.

  11. Searching for axionlike particles in flavor-changing neutral current processes [A new flavor of searches for axion-like particles

    DOE PAGES

    Izaguirre, Eder; Lin, Tongyan; Shuve, Brian

    2017-03-15

    Here, we propose new searches for axion-like particles (ALPs) produced in flavor-changing neutral current (FCNC) processes. This proposal exploits the often-overlooked coupling of ALPs to W ± bosons, leading to FCNC production of ALPs even in the absence of a direct coupling to fermions. Our proposed searches for resonant ALP production in decays such as B→K(*)a, a→γγ, and K→πa, a→γγ could greatly improve upon the current sensitivity to ALP couplings to standard model particles. Finally, we also determine analogous constraints and discovery prospects for invisibly decaying ALPs.

  12. A graphite based STT-RAM cell with reduction in switching current

    NASA Astrophysics Data System (ADS)

    Varghani, Ali; Peiravi, Ali

    2015-10-01

    Spin Transfer Torque Random Access Memory (STT-RAM) is a serious candidate for "universal memory" because of its non-volatility, fast access time, high density, good scalability, high endurance and relatively low power dissipation. However, problems with low write speed and large write current are important existing challenges in STT-RAM design and there is a tradeoff between them and data retention time. In this study, a novel STT-RAM cell structure which uses perfect graphite based Magnetic Tunnel Junction (MTJ) is proposed. First, the cross-section of the structure is selected to be an ellipse of 45 nm and 180 nm dimensions and a six-layer graphite is used as tunnel barrier. By passing a lateral current with a short pulse width (before applying STT current and independent of it) through four middle graphene layers of the tunnel barrier, a 27% reduction in the amplitude of the switching current (for fast switching time of 2 ns) or a 58% reduction in its pulse width is achieved without any reduction in data retention time. Finally, the effect of downscaling of technology on the proposed structure is evaluated. A reduction of 31.6% and 9% in switching current is achieved for 90 and 22 nm cell width respectively by passing sufficient current (100 μA with 0.1 ns pulse width) through the tunnel barrier. Simulations are done using Object Oriented Micro Magnetic Framework (OOMMF).

  13. Discussions and decisions of the 2012–2014 International Committee on Taxonomy of Viruses (ICTV) Filoviridae Study Group, January 2012–June 2013

    PubMed Central

    Bukreyev, Alexander A.; Chandran, Kartik; Dolnik, Olga; Dye, John M.; Ebihara, Hideki; Leroy, Eric M.; Mühlberger, Elke; Netesov, Sergey V.; Patterson, Jean L.; Paweska, Janusz T.; Saphire, Erica Ollmann; Smither, Sophie J.; Takada, Ayato; Towner, Jonathan S.; Volchkov, Viktor E.; Warren, Travis K.; Kuhn, Jens H.

    2013-01-01

    The International Committee on Taxonomy of Viruses (ICTV) Filoviridae Study Group prepares proposals on the classification and nomenclature of filoviruses to reflect current knowledge or to correct disagreements with the International Code of Virus Classification and Nomenclature (ICVCN). In recent years, filovirus taxonomy has been corrected and updated, but parts of it remain controversial, and several topics remain to be debated. This article summarizes the decisions and discussion of the currently acting ICTV Filoviridae Study Group since its inauguration in January 2012. PMID:24122154

  14. 77 FR 57588 - Agency Information Collection; Proposed Revisions to a Currently Approved Information Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-18

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Agency Information Collection; Proposed Revisions to a Currently Approved Information Collection AGENCY: Bureau of Reclamation, Interior. ACTION... editorial nature, and are designed to assist the respondents by increasing their understanding of the forms...

  15. 77 FR 57587 - Agency Information Collection; Proposed Revisions to a Currently Approved Information Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-18

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Agency Information Collection; Proposed Revisions to a Currently Approved Information Collection AGENCY: Bureau of Reclamation, Interior. ACTION... forms and the corresponding instructions are of an editorial nature, and are designed to assist the...

  16. Searching for efficient Markov chain Monte Carlo proposal kernels

    PubMed Central

    Yang, Ziheng; Rodríguez, Carlos E.

    2013-01-01

    Markov chain Monte Carlo (MCMC) or the Metropolis–Hastings algorithm is a simulation algorithm that has made modern Bayesian statistical inference possible. Nevertheless, the efficiency of different Metropolis–Hastings proposal kernels has rarely been studied except for the Gaussian proposal. Here we propose a unique class of Bactrian kernels, which avoid proposing values that are very close to the current value, and compare their efficiency with a number of proposals for simulating different target distributions, with efficiency measured by the asymptotic variance of a parameter estimate. The uniform kernel is found to be more efficient than the Gaussian kernel, whereas the Bactrian kernel is even better. When optimal scales are used for both, the Bactrian kernel is at least 50% more efficient than the Gaussian. Implementation in a Bayesian program for molecular clock dating confirms the general applicability of our results to generic MCMC algorithms. Our results refute a previous claim that all proposals had nearly identical performance and will prompt further research into efficient MCMC proposals. PMID:24218600

  17. Orbit Clustering Based on Transfer Cost

    NASA Technical Reports Server (NTRS)

    Gustafson, Eric D.; Arrieta-Camacho, Juan J.; Petropoulos, Anastassios E.

    2013-01-01

    We propose using cluster analysis to perform quick screening for combinatorial global optimization problems. The key missing component currently preventing cluster analysis from use in this context is the lack of a useable metric function that defines the cost to transfer between two orbits. We study several proposed metrics and clustering algorithms, including k-means and the expectation maximization algorithm. We also show that proven heuristic methods such as the Q-law can be modified to work with cluster analysis.

  18. Massive Multiplayer Online Role Playing Games and Interaction: A Measurable Model of Interaction for Online Learning

    ERIC Educational Resources Information Center

    Anderson, Bodi

    2014-01-01

    This current study examines the need for operational definitions of the concept of interaction in distance education studies. It is proposed that a discourse analysis of linguistic features conversation noted as being representative of interaction can be used to operationalize interaction in synchronous CMC. This study goes on compare two…

  19. The minipig as an animal model to study Mycobacterium tuberculosis infection and natural transmission

    USDA-ARS?s Scientific Manuscript database

    Infants and children with tuberculosis (TB) account for more than 20% of cases in endemic countries. Current animal models study TB during adulthood but animal models for adolescent and infant TB are scarce. Here we propose that minipigs can be used as an animal model to study adult, adolescent and ...

  20. Screen Design Principles of Computer-Aided Instructional Software for Elementary School Students

    ERIC Educational Resources Information Center

    Berrin, Atiker; Turan, Bülent Onur

    2017-01-01

    This study aims to present primary school students' views about current educational software interfaces, and to propose principles for educational software screens. The study was carried out with a general screening model. Sample group of the study consisted of sixth grade students in Sehit Ögretmen Hasan Akan Elementary School. In this context,…

  1. An Eye-Tracking Study of How Color Coding Affects Multimedia Learning

    ERIC Educational Resources Information Center

    Ozcelik, Erol; Karakus, Turkan; Kursun, Engin; Cagiltay, Kursat

    2009-01-01

    Color coding has been proposed to promote more effective learning. However, insufficient evidence currently exists to show how color coding leads to better learning. The goal of this study was to investigate the underlying cause of the color coding effect by utilizing eye movement data. Fifty-two participants studied either a color-coded or…

  2. Proposed Sources of Coaching Efficacy: A Meta-Analysis.

    PubMed

    Myers, Nicholas D; Park, Sung Eun; Ahn, Soyeon; Lee, Seungmin; Sullivan, Philip J; Feltz, Deborah L

    2017-08-01

    Coaching efficacy refers to the extent to which a coach believes that he or she has the capacity to affect the learning and performance of his or her athletes. The purpose of the current study was to empirically synthesize findings across the extant literature to estimate relationships between the proposed sources of coaching efficacy and each of the dimensions of coaching efficacy. A literature search yielded 20 studies and 278 effect size estimates that met the inclusion criteria. The overall relationship between the proposed sources of coaching efficacy and each dimension of coaching efficacy was positive and ranged from small to medium in size. Coach gender and level coached moderated the overall relationship between the proposed sources of coaching efficacy and each of the dimensions of coaching efficacy. Results from this meta-analysis provided some evidence for both the utility of, and possible revisions to, the conceptual model of coaching efficacy.

  3. Resilient distributed control in the presence of misbehaving agents in networked control systems.

    PubMed

    Zeng, Wente; Chow, Mo-Yuen

    2014-11-01

    In this paper, we study the problem of reaching a consensus among all the agents in the networked control systems (NCS) in the presence of misbehaving agents. A reputation-based resilient distributed control algorithm is first proposed for the leader-follower consensus network. The proposed algorithm embeds a resilience mechanism that includes four phases (detection, mitigation, identification, and update), into the control process in a distributed manner. At each phase, every agent only uses local and one-hop neighbors' information to identify and isolate the misbehaving agents, and even compensate their effect on the system. We then extend the proposed algorithm to the leaderless consensus network by introducing and adding two recovery schemes (rollback and excitation recovery) into the current framework to guarantee the accurate convergence of the well-behaving agents in NCS. The effectiveness of the proposed method is demonstrated through case studies in multirobot formation control and wireless sensor networks.

  4. Low-flow characteristics of streams under natural and diversion conditions, Waipiʻo Valley, Island of Hawaiʻi, Hawaiʻi

    USGS Publications Warehouse

    Fontaine, Richard A.

    2012-01-01

    Over the past 100 years, natural streamflow in Waipiʻo Valley has been reduced by the transfer of water out of the valley by Upper and Lower Hāmākua Ditches. The physical condition and diversion practices along the two ditch systems have varied widely over the years, and as a result, so have their effects on natural streamflow in Waipiʻo Valley. Recent renovation and improvements to Lower Hāmākua Ditch system, along with proposals for its future operation and water-diversion strategies, have unknown implications. The purpose of this report is to quantify the availability of streamflow and to determine the effects of current and proposed diversion strategies on the low-flow hydrology in Waipiʻo Valley. In this report, the low-flow hydrology of Waipiʻo Valley is described in terms of flow-duration statistics. Flow-duration statistics were computed for three locations in the Waipiʻo Valley study area where long-term surface-water gaging stations have been operated. Using a variety of streamflow record-extension techniques, flow-duration statistics were estimated at an additional 13 locations where only few historical data are available or where discharge measurements were made as part of this study. Flow-duration statistics were computed to reflect natural conditions, current (2000-2005) diversion conditions, and proposed future diversion conditions at the 16 locations. At the downstream limit of the study area, on Wailoa Stream at an altitude of 190 feet, a baseline for evaluating the availability of streamflow is provided by computed flow-duration statistics that are representative of natural, no-diversion conditions. At the Wailoa gaging station, 95- and 50-percentile discharges under natural conditions were determined to be 86 and 112 cubic feet per second, respectively. Under 1965-1969 diversion conditions, natural 95- and 50-percentile discharges were reduced by 52 and 53 percent, to 41 and 53 cubic feet per second, respectively. Under current (2000-2005) diversion conditions, natural 95- and 50-percentile discharges were reduced by 21 and 24 percent, to 68 and 85 cubic feet per second, respectively. Under proposed future diversion conditions, natural 95- and 50-percentile discharges would be reduced by 33 and 24 percent, to 58 and 85 cubic feet per second, respectively. Compared to discharges that reflect current (2000-2005) diversion conditions, proposed future diversion conditions would reduce 95-percentile discharges, which are representative of moderate drought levels in the stream, by 15 percent. No change would be expected in 50-percentile discharges, which are representative of normal conditions. The effects of current (2000-2005) and proposed future diversion conditions on the natural flow of streams in the Waipiʻo Valley study area differ, depending on the location. Under current (2000-2005) diversion conditions, reductions in natural 95- or 50-percentile discharges of greater than 30 percent were found in Kawainui Stream downstream from Upper Hamakua Ditch to an altitude of about 1,435 feet and in the reach of Waimā Stream between Upper and Lower Hāmākua Ditches. Under proposed future diversion conditions, reductions in natural 95- or 50-percentile discharges of greater than 30 percent were found in Kawainui Stream downstream from Upper Hamakua Ditch to an altitude of about 1,435 feet, in the reach of Waimā Stream between Upper and Lower Hāmākua Ditches, and along most stream reaches downstream from Lower Hāmākua Ditch, except for Waimā Stream.

  5. The Cajal school and the physiological role of astrocytes: a way of thinking

    PubMed Central

    Navarrete, Marta; Araque, Alfonso

    2014-01-01

    Cajal is widely recognized by the scientific community for his important contributions to our knowledge of the neuronal organization of the nervous system. His studies on neuroglial cells are less recognized, yet they are no less relevant to our current understanding of the cellular bases of brain structure. Two pioneering studies published a century ago –“Something about the physiological significance of neuroglia” (Ramón y Cajal, 1897) and “A contribution to the understanding of neuroglia in the human brain” (Ramón y Cajal, 1913)—focused on glial cells and their role in brain physiology. Novel findings obtained using state-of-the-art and sophisticated technologies largely confirm many of the groundbreaking hypotheses proposed by Cajal related to the structural-functional properties of neuroglia. Here we propose to the reader a journey guided by the ideas of Cajal through the recent findings on the functional significance of astrocytes, the most abundant neuroglial cell type in the nervous system. Astrocyte–neuron interaction, which represents an emerging field in current neuroscience with important implications for our understanding of the cellular processes underlying brain function, has its roots in many of the original concepts proposed by Cajal. PMID:24904302

  6. MOSFET-BJT hybrid mode of the gated lateral bipolar junction transistor for C-reactive protein detection.

    PubMed

    Yuan, Heng; Kwon, Hyurk-Choon; Yeom, Se-Hyuk; Kwon, Dae-Hyuk; Kang, Shin-Won

    2011-10-15

    In this study, we propose a novel biosensor based on a gated lateral bipolar junction transistor (BJT) for biomaterial detection. The gated lateral BJT can function as both a BJT and a metal-oxide-semiconductor field-effect transistor (MOSFET) with both the emitter and source, and the collector and drain, coupled. C-reactive protein (CRP), which is an important disease marker in clinical examinations, can be detected using the proposed device. In the MOSFET-BJT hybrid mode, the sensitivity, selectivity, and reproducibility of the gated lateral BJT for biosensors were evaluated in this study. According to the results, in the MOSFET-BJT hybrid mode, the gated lateral BJT shows good selectivity and reproducibility. Changes in the emitter (source) current of the device for CRP antigen detection were approximately 0.65, 0.72, and 0.80 μA/decade at base currents of -50, -30, and -10 μA, respectively. The proposed device has significant application in the detection of certain biomaterials that require a dilution process using a common biosensor, such as a MOSFET-based biosensor. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. The Role of Clouds in the Long-Term Habitability of Planets

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Tolbert, Margaret

    2000-01-01

    We proposed to conduct theoretical and laboratory investigations of the role that clouds play in the long-term climate history of the Earth and other habitable planets. We made significant progress in the first area we proposed to consider- the properties of carbon dioxide clouds in atmospheres that are rich in carbon dioxide. We submitted a modeling paper on the microphysical properties of the clouds to Icarus showing that such clouds are unlikely to play an important role in the early greenhouses on Earth or Mars. The model was based on lab studies of the nucleation and growth of carbon dioxide. We have also submitted a manuscript describing these lab studies to Icarus. These lab studies are critical not only to the ancient Mars atmosphere, but also to the current one. We also submitted a paper to Nature describing modeling of current Martian CO2 clouds. We will also model the properties of water clouds in the early history of Earth. Early in Earth's history the atmosphere contained no free oxygen. Without oxygen, sulfate aerosols that are currently the dominant cloud nuclei, cannot form. Without such nuclei the cloud structure would have been far different than it is now. We initiated studies of the aerosols on Titan as part of this work. We reported these studies in a short paper on nucleation and in several conferences.

  8. The Enterprise Training System and Training Content Analysis of Selected Manufacturing Companies in Taiwan, R.O.C.: A Case Study.

    ERIC Educational Resources Information Center

    Kuo, Mike Chu-Hsun

    A study investigated the current enterprise training system in Taiwan and proposed suitable training suggestions for manufacturing industry through a carefully designed case study. Literature review and field study were used to gather research data. Interviews were conducted at four large manufacturing companies during the period October 1990 to…

  9. Submitting for Dollars: Playing the Funding Game to Promote Transcultural Nursing.

    PubMed

    Amerson, Roxanne

    2015-07-01

    Research requires funding! Every researcher understands the crucial role that money plays in implementing a research study. Research for nursing is no different. In the current economic environment, funding sources have become limited. Therefore, researchers need to be prepared to submit grant proposals which will give them a competitive edge over other proposals. This paper will: (1) describe the development of a grant proposal for National Institutes of Health funding, and (2) provide suggestions to novice researchers about how to write a proposal that has the potential to receive a fundable score. This team of early stage investigators submitted a proposal which received a fundable score, but was not selected for funding. The proposal was revised, re-submitted, and received a highly competitive score that did result in funding. The lessons learned from this process can be useful for other nurses seeking to secure funding for their research projects.

  10. Teaching the Urban Student as a Whole: Utilizing Universal Skills in Science and Social Studies Interdisciplinary Curricula

    NASA Astrophysics Data System (ADS)

    Berg, Christianna

    The purpose for this project is to utilize interdisciplinary curricula to emphasize transferable skills across the four main subject areas: reading, mathematics, science, and social studies. This project aims to provide a background for the creation of an interdisciplinary curricula that can be adjusted to current instructional programs being used in any classroom. The proposed curriculum is intended for a science and social studies elementary classroom where students rotate to a different mathematics and language arts classroom, but it could be applied to older grades or to self-contained classes. The proposed curriculum emphasizes problem solving, reading, and writing skills.

  11. Design of a low-cost, compact SRF accelerator for flue gas and wastewater treatment

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

    Ciovati, Gianluigi

    2016-04-01

    Funding is being requested pursuant to a proposal that was submitted and reviewed through the Portfolio Analysis and Management System (PAMS). PAMS Proposal ID: 222439. The proposed project consists of the design of a novel superconducting continuous-wave accelerator capable of providing a beam current of ~1 A at an energy of 1-2 MeV for the treatment of flue gases and wastewater streams. The novel approach consists on studying the feasibility of using a single-cell Nb cavity coated with a thin Nb3Sn layer of the inner surface and conductively cooled by to 4.2 K by cryocoolers inside a compact cryomodule. Themore » proposed study will include beam transport simulations, thermal and mechanical engineering analysis of the cryomodule and a cost analysis for both the fabrications costs and the operational and maintenance costs of such accelerator. The outcome of the project will be a report summarizing the analysis and results from the design study.« less

  12. Mechanisms for radiation damage in DNA. Progress report, January 1, 1980-December 31, 1980

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

    Sevilla, M D

    1980-09-01

    In this project several mechanisms are proposed for radiation damage to DNA constituents and DNA, and a series of experiments detailed utilizing electron spin resonance spectrometry to test the proposed mechanisms. Under current investigation are irradiated systems of DNA constituents which may shed light on indirect effects. In addition, studies of radiation effects on lipids have been undertaken which will shed light on the only other proposed site for cell kill, the membrane. Studies completed during the past year are: (1) ..pi.. cations produced in DNA bases by attack of oxidizing radicals; (2) INDO studies of radicals produced in peptidesmore » and carboxylic acid model compounds; (3) electron reactions with carboxylic acids, ketones and aldehydes; and (4) ..gamma..-irradiation of esters and triglycerides. Progress has been made this year in a study of radicals generated in model compounds for the sugar-phosphate backbone.« less

  13. Development of a Telemetric, Miniaturized Electrochemical Amperometric Analyzer.

    PubMed

    Jung, Jaehyo; Lee, Jihoon; Shin, Siho; Kim, Youn Tae

    2017-10-23

    In this research, we developed a portable, three-electrode electrochemical amperometric analyzer that can transmit data to a PC or a tablet via Bluetooth communication. We performed experiments using an indium tin oxide (ITO) glass electrode to confirm the performance and reliability of the analyzer. The proposed analyzer uses a current-to-voltage (I/V) converter to convert the current generated by the reduction-oxidation (redox) reaction of the buffer solution to a voltage signal. This signal is then digitized by the processor. The configuration of the power and ground of the printed circuit board (PCB) layer is divided into digital and analog parts to minimize the noise interference of each part. The proposed analyzer occupies an area of 5.9 × 3.25 cm² with a current resolution of 0.4 nA. A potential of 0~2.1 V can be applied between the working and the counter electrodes. The results of this study showed the accuracy of the proposed analyzer by measuring the Ruthenium(III) chloride ( Ru III ) concentration in 10 mM phosphate-buffered saline (PBS) solution with a pH of 7.4. The measured data can be transmitted to a PC or a mobile such as a smartphone or a tablet PC using the included Bluetooth module. The proposed analyzer uses a 3.7 V, 120 mAh lithium polymer battery and can be operated for 60 min when fully charged, including data processing and wireless communication.

  14. Development of a Telemetric, Miniaturized Electrochemical Amperometric Analyzer

    PubMed Central

    Lee, Jihoon; Shin, Siho; Kim, Youn Tae

    2017-01-01

    In this research, we developed a portable, three-electrode electrochemical amperometric analyzer that can transmit data to a PC or a tablet via Bluetooth communication. We performed experiments using an indium tin oxide (ITO) glass electrode to confirm the performance and reliability of the analyzer. The proposed analyzer uses a current-to-voltage (I/V) converter to convert the current generated by the reduction-oxidation (redox) reaction of the buffer solution to a voltage signal. This signal is then digitized by the processor. The configuration of the power and ground of the printed circuit board (PCB) layer is divided into digital and analog parts to minimize the noise interference of each part. The proposed analyzer occupies an area of 5.9 × 3.25 cm2 with a current resolution of 0.4 nA. A potential of 0~2.1 V can be applied between the working and the counter electrodes. The results of this study showed the accuracy of the proposed analyzer by measuring the Ruthenium(III) chloride (RuIII) concentration in 10 mM phosphate-buffered saline (PBS) solution with a pH of 7.4. The measured data can be transmitted to a PC or a mobile such as a smartphone or a tablet PC using the included Bluetooth module. The proposed analyzer uses a 3.7 V, 120 mAh lithium polymer battery and can be operated for 60 min when fully charged, including data processing and wireless communication. PMID:29065534

  15. Barbers Point Harbor, Hawaii, Jetty Modification Study

    DTIC Science & Technology

    2008-11-01

    jetty lengths do not adversely impact the wave environment in the vicinity of the jetty. Production phase Figure 18 shows the normalized incident...objective of these current measurements is to show that the proposed jetty will not have any adverse impacts on the existing current patterns with no...with minimal construction costs and impact on the environment. ERDC/CHL TR-08-16 83 References Briggs, M. J., L. S. Lillycrop, G. S. Harkins

  16. 76 FR 18810 - Proposed Collection; Comment Request for Revision of a Currently Approved Information Collection...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ..., Federal Employee Insurance Operations, Healthcare & Insurance, U.S. Office of Personnel Management, 1900 E... OFFICE OF PERSONNEL MANAGEMENT Proposed Collection; Comment Request for Revision of a Currently... Personnel Management. ACTION: Notice. SUMMARY: In accordance with the Paperwork Reduction Act of 1995 (Pub...

  17. Electromigration analysis of solder joints under ac load: A mean time to failure model

    NASA Astrophysics Data System (ADS)

    Yao, Wei; Basaran, Cemal

    2012-03-01

    In this study, alternating current (ac) electromigration (EM) degradation simulations were carried out for Sn95.5%Ag4.0%Cu0.5 (SAC405- by weight) solder joints. Mass transport analysis was conducted with viscoplastic material properties for quantifying damage mechanism in solder joints. Square, sine, and triangle current wave forms ac were used as input signals. dc and pulsed dc (PDC) electromigration analysis were conducted for comparison purposes. The maximum current density ranged from 2.2×106A/cm2 to 5.0×106A/cm2, frequency ranged from 0.05 Hz to 5 Hz with ambient temperature varying from 350 K to 450 K. Because the room temperature is nearly two-thirds of SAC solder joint's melting point on absolute temperature scale (494.15 K), viscoplastic material model is essential. Entropy based damage evolution model was used to investigate mean time to failure (MTF) behavior of solder joints subjected to ac stressing. It was observed that MTF was inversely proportional to ambient temperature T1.1 in Celsius and also inversely proportional to current density j0.27 in A/cm2. Higher frequency will lead to a shorter lifetime with in the frequency range we studied, and a relationship is proposed as MTF∝f-0.41. Lifetime of a solder joint subjected to ac is longer compared with dc and PDC loading conditions. By introducing frequency, ambient temperature and current density dependency terms, a modified MTTF equation was proposed for solder joints subjected to ac current stressing.

  18. Small business innovation research: Program solicitation

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This, the seventh annual SBIR solicitation by NASA, describes the program, identifies eligibility requirements, outlines the required proposal format and content, states proposal preparation and submission requirements, describes the proposal evaluation and award selection process, and provides other information to assist those interested in participating in NASA's SBIR program. It also identifies the Technical Topics and Subtopics in which SBIR Phase 1 proposals are solicited in 1989. These Topics and Subtopics cover a broad range of current NASA interests, but do not necessarily include all areas in which NASA plans or currently conducts research. High-risk high pay-off innovations are desired.

  19. 76 FR 21938 - Potential Environmental Impacts of the Proposed Runway 13 Extension and Associated Actions for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-19

    ... current and projected levels of aviation by the design aircraft family. Eight alternatives were studied...) Unconditional approval of the Airport Layout Plan (ALP) for the development listed in the EA and the decision...

  20. A comprehensive equivalent circuit model of all-vanadium redox flow battery for power system analysis

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Zhao, Jiyun; Wang, Peng; Skyllas-Kazacos, Maria; Xiong, Binyu; Badrinarayanan, Rajagopalan

    2015-09-01

    Electrical equivalent circuit models demonstrate excellent adaptability and simplicity in predicting the electrical dynamic response of the all-vanadium redox flow battery (VRB) system. However, only a few publications that focus on this topic are available. The paper presents a comprehensive equivalent circuit model of VRB for system level analysis. The least square method is used to identify both steady-state and dynamic characteristics of VRB. The inherent features of the flow battery such as shunt current, ion diffusion and pumping energy consumption are also considered. The proposed model consists of an open-circuit voltage source, two parasitic shunt bypass circuits, a 1st order resistor-capacitor network and a hydraulic circuit model. Validated with experimental data, the proposed model demonstrates excellent accuracy. The mean-error of terminal voltage and pump consumption are 0.09 V and 0.49 W respectively. Based on the proposed model, self-discharge and system efficiency are studied. An optimal flow rate which maximizes the system efficiency is identified. Finally, the dynamic responses of the proposed VRB model under step current profiles are presented. Variables such as SOC and stack terminal voltage can be provided.

  1. Capacitors Would Help Protect Against Hypervelocity Impacts

    NASA Technical Reports Server (NTRS)

    Edwards, David; Hubbs, Whitney; Hovater, Mary

    2007-01-01

    A proposal investigates alternatives to the present bumper method of protecting spacecraft against impacts of meteoroids and orbital debris. The proposed method is based on a British high-voltage-capacitance technique for protecting armored vehicles against shaped-charge warheads. A shield, according to the proposal, would include a bare metal outer layer separated by a gap from an inner metal layer covered with an electrically insulating material. The metal layers would constitute electrodes of a capacitor. A bias potential would be applied between the metal layers. A particle impinging at hypervelocity on the outer metal layer would break apart into a debris cloud that would penetrate the electrical insulation on the inner metal layer. The cloud would form a path along which electric current could flow between the metal layers, thereby causing the capacitor to discharge. With proper design, the discharge current would be large enough to vaporize the particles in the debris cloud to prevent penetration of the spacecraft. The shield design can be mass optimized to be competitive with existing bumper designs. Parametric studies were proposed to determine optimum correction between bias voltage, impacting particle velocity, gap space, and insulating material required to prevent spacecraft penetration.

  2. Uniqueness and reconstruction in magnetic resonance-electrical impedance tomography (MR-EIT).

    PubMed

    Ider, Y Ziya; Onart, Serkan; Lionheart, William R B

    2003-05-01

    Magnetic resonance-electrical impedance tomography (MR-EIT) was first proposed in 1992. Since then various reconstruction algorithms have been suggested and applied. These algorithms use peripheral voltage measurements and internal current density measurements in different combinations. In this study the problem of MR-EIT is treated as a hyperbolic system of first-order partial differential equations, and three numerical methods are proposed for its solution. This approach is not utilized in any of the algorithms proposed earlier. The numerical solution methods are integration along equipotential surfaces (method of characteristics), integration on a Cartesian grid, and inversion of a system matrix derived by a finite difference formulation. It is shown that if some uniqueness conditions are satisfied, then using at least two injected current patterns, resistivity can be reconstructed apart from a multiplicative constant. This constant can then be identified using a single voltage measurement. The methods proposed are direct, non-iterative, and valid and feasible for 3D reconstructions. They can also be used to easily obtain slice and field-of-view images from a 3D object. 2D simulations are made to illustrate the performance of the algorithms.

  3. [Criteria for prioritising patients on surgical waiting lists in the National Health System].

    PubMed

    Allepuz, A; Espallargues, M; Martínez, O

    2009-01-01

    To survey the importance of previously proposed criteria for prioritising patients on surgical waiting lists and to analyse their use in daily practice. Cross-sectional study through a self-auto-administered postal questionnaire to hospital managers, medical directors, admissions managers, and department heads of general surgery, ophthalmology, orthopaedics and traumatology surgery and vascular surgery from 139 centres. The questionnaire comprised 3 sections: a) 3 to 5 of the most important criteria had to be selected and their use in daily practice had to be assessed; b) new criteria were proposed, c) socio-demographic data. The mean and its standard deviation of each criterion of importance were calculated. The proposed criteria were categorised and their frequency was calculated. The questionnaire was answered by the 22% of those surveyed. Disease severity, speed of progression, waiting time and pain were the criteria considered as most important and were the most used. The current clinical situation and the professional environment were the two most common categories defined from the criteria proposed by those surveyed. The surgical priority should be determined by other criteria related to surgery necessity besides waiting time. Establishing prioritisation criteria could enable current implicit criteria to be used explicitly.

  4. Conical structures for highly efficient solar cell applications

    NASA Astrophysics Data System (ADS)

    Korany, Fatma M. H.; Hameed, Mohamed Farhat O.; Hussein, Mohamed; Mubarak, Roaa; Eladawy, Mohamed I.; Obayya, Salah Sabry A.

    2018-01-01

    Improving solar cell efficiency is a critical research topic. Nowadays, light trapping techniques are a promising way to enhance solar cell performance. A modified nanocone nanowire (NW) is proposed and analyzed for solar cell applications. The suggested NW consists of conical and truncated conical units. The geometrical parameters are studied using a three-dimensional (3-D) finite difference time-domain (FDTD) method to achieve broadband absorption through the reported design and maximize its ultimate efficiency. The analyzed parameters are absorption spectra, ultimate efficiency, and short circuit current density. The numerical results prove that the proposed structure is superior compared with cone, truncated cone, and cylindrical NWs. The reported design achieves an ultimate efficiency of 44.21% with substrate and back reflector. Further, short circuit current density of 36.17 mA / cm2 is achieved by the suggested NW. The electrical performance analysis of the proposed structure including doping concentration, junction thickness, and Shockley-Read-Hall recombination is also investigated. The electrical simulations show that a power conversion efficiency of 17.21% can be achieved using the proposed NW. The modified nanocone has advantages of broadband absorption enhancement, low cost, and fabrication feasibility.

  5. Conversive disorders among children and adolescents: towards new "complementarist" paradigms?

    PubMed

    Ouss, L; Tordjman, E

    2014-10-01

    This paper aims to describe current questions concerning conversive disorders among children and adolescents. We first describe prevalence and clinical characteristics of these. Many unresolved questions remain. Why do patients show excess, or loss of function? Attachment theory offers a relevant framework to answer this question. Does neurobiology of conversion disorders shed light on conversive processes? Current neurobiological research paradigms focus on the symptom, trying to infer processes, instead of proposing paradigms that test theoretical hypotheses. The most convincing theoretical framework that has already proposed a coherent theory of conversion is a psychodynamic one, which has not yet been tested with neurobiological paradigms. The interest of studying child and adolescent conversive disorders is to provide a means to more deeply investigate the two challenges we face: theoretical, and clinical ones. It provides the opportunity to access a pathopsychological process at its roots, not yet hidden by many defensive, rationalizing attitudes, and to better explore environmental features. We propose a "complementarist" model, which allows the combination of different approaches (neural, cognitive, environmental, attachment, intra-psychic) and permits proposal of different levels of therapeutic targets and means. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  6. Reference values of fractional excretion of exhaled nitric oxide among non-smokers and current smokers.

    PubMed

    Torén, Kjell; Murgia, Nicola; Schiöler, Linus; Bake, Björn; Olin, Anna-Carin

    2017-08-25

    Fractional exhaled nitric oxide (FE NO ) is used to assess of airway inflammation; diagnose asthma and monitor adherence to advised therapy. Reliable and accurate reference values for FE NO are needed for both non-smoking and current smoking adults in the clinical setting. The present study was performed to establish reference adult FE NO values among never-smokers, former smokers and current smokers. FE NO was measured in 5265 subjects aged 25-75 years in a general-population study, using a chemiluminescence (Niox ™) analyser according to the guidelines of the American Thoracic Society and the European Respiratory Society. Atopy was based on the presence of immunoglobulin E (IgE) antibodies to common inhalant allergens (measured using Phadiatop® test). Spirometry without bronchodilation was performed and forced vital capacity (FVC), forced expired volume in 1 s (FEV 1 ) and the ratio of FEV 1 to FVC values were obtained. After excluding subjects with asthma, chronic bronchitis, spirometric airway obstruction and current cold, 3378 subjects remained. Equations for predictions of FE NO values were modelled using nonparametric regression models. FE NO levels were similar in never-smokers and former smokers, and these two groups were therefore merged into a group termed "non-smokers". Reference equations, including the 5th and 95th percentiles, were generated for female and male non-smokers, based on age, height and atopy. Regression models for current smokers were unstable. Hence, the proposed reference values for current smokers are based on the univariate distribution of FE NO and fixed cut-off limits. Reference values for FE NO among respiratory healthy non-smokers should be outlined stratified for gender using individual reference values. For current smokers separate cut-off limits are proposed.

  7. A Single-Phase Current Source Solar Inverter with Constant Instantaneous Power, Improved Reliability, and Reduced-Size DC-Link Filter

    NASA Astrophysics Data System (ADS)

    Bush, Craig R.

    This dissertation presents a novel current source converter topology that is primarily intended for single-phase photovoltaic (PV) applications. In comparison with the existing PV inverter technology, the salient features of the proposed topology are: a) the low frequency (double of line frequency) ripple that is common to single-phase inverters is greatly reduced; b) the absence of low frequency ripple enables significantly reduced size pass components to achieve necessary DC-link stiffness and c) improved maximum power point tracking (MPPT) performance is readily achieved due to the tightened current ripple even with reduced-size passive components. The proposed topology does not utilize any electrolytic capacitors. Instead an inductor is used as the DC-link filter and reliable AC film capacitors are utilized for the filter and auxiliary capacitor. The proposed topology has a life expectancy on par with PV panels. The proposed modulation technique can be used for any current source inverter where an unbalanced three-phase operation is desires such as active filters and power controllers. The proposed topology is ready for the next phase of microgrid and power system controllers in that it accepts reactive power commands. This work presents the proposed topology and its working principle supported by with numerical verifications and hardware results. Conclusions and future work are also presented.

  8. Optimization of diffusion-weighted single-refocused spin-echo EPI by reducing eddy-current artifacts and shortening the echo time.

    PubMed

    Shrestha, Manoj; Hok, Pavel; Nöth, Ulrike; Lienerth, Bianca; Deichmann, Ralf

    2018-03-30

    The purpose of this work was to optimize the acquisition of diffusion-weighted (DW) single-refocused spin-echo (srSE) data without intrinsic eddy-current compensation (ECC) for an improved performance of ECC postprocessing. The rationale is that srSE sequences without ECC may yield shorter echo times (TE) and thus higher signal-to-noise ratios (SNR) than srSE or twice-refocused spin-echo (trSE) schemes with intrinsic ECC. The proposed method employs dummy scans with DW gradients to drive eddy currents into a steady state before data acquisition. Parameters of the ECC postprocessing algorithm were also optimized. Simulations were performed to obtain minimum TE values for the proposed sequence and sequences with intrinsic ECC. Experimentally, the proposed method was compared with standard DW-trSE imaging, both in vitro and in vivo. Simulations showed substantially shorter TE for the proposed method than for methods with intrinsic ECC when using shortened echo readouts. Data of the proposed method showed a marked increase in SNR. A dummy scan duration of at least 1.5 s improved performance of the ECC postprocessing algorithm. Changes proposed for the DW-srSE sequence and for the parameter setting of the postprocessing ECC algorithm considerably reduced eddy-current artifacts and provided a higher SNR.

  9. Exact mapping of the 2+1 Dirac oscillator onto the Jaynes-Cummings model: Ion-trap experimental proposal

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

    Bermudez, A.; Martin-Delgado, M. A.; Solano, E.

    2007-10-15

    We study the dynamics of the 2+1 Dirac oscillator exactly and find spin oscillations due to a Zitterbewegung of purely relativistic origin. We find an exact mapping of this quantum-relativistic system onto a Jaynes-Cummings model, describing the interaction of a two-level atom with a quantized single-mode field. This equivalence allows us to map a series of quantum optical phenomena onto the relativistic oscillator and vice versa. We make a realistic experimental proposal, in reach with current technology, for studying the equivalence of both models using a single trapped ion.

  10. The ISSAS Model: Understanding the Information Needs of Sexual Assault Survivors on College Campuses

    ERIC Educational Resources Information Center

    Skinner, Julia; Gross, Melissa

    2017-01-01

    Sexual assault is a prevalent, yet underreported and stigmatizing crime that disproportionately affects college-age students. The literature of Library & Information Studies does not currently address the ways in which survivors may seek information after an assault. Blending findings from Psychology and LIS, this study proposes the…

  11. Conceptualizing Gender, Contextualizing Curriculum: A Case Study of Teacher Education Coursework

    ERIC Educational Resources Information Center

    Kean, M. Eli

    2017-01-01

    This study explores and theorizes around issues of transgender curriculum in teacher education courses. Using a conceptual framework informed by both transgender theory and curriculum theory, I propose a Critical Trans Framework to analyze what trans-related curricular materials are currently used in teacher education courses and what factors…

  12. Discrimination against Rural-to-Urban Migrants: The Role of the Hukou System in China

    PubMed Central

    Kuang, Lei; Liu, Li

    2012-01-01

    China's rural-urban dual society system is instituted by its unique hukou system. This system causes inequalities in social status between permanent urban and rural residents, and discrimination against rural-to-urban migrants is thus prevalent. A series of studies, based on system justification theory, sought to address the impact of the hukou system on the discrimination against rural-to-urban migrants. Study 1 showed that the justification of the hukou system could predict discrimination operationalized using a social distance measure. Study 2 found that priming of the proposed abolishment of the current hukou system led to reduced social distance. Study 3, using a recruiting scenario, further demonstrated that priming of the proposed abolishment of the system led to reduced discrimination in salary decision. Consistent with our predictions, discrimination against rural-to-urban migrants could be triggered by justifying the current hukou system, while priming of the abolishment of the system serves to decrease discrimination. The present research thereby sheds light on China's reform of its hukou system to achieve social justice and equality from a psychological perspective. PMID:23144794

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

    NASA Astrophysics Data System (ADS)

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

    2018-06-01

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

  14. Single-stage three-phase boost power factor correction circuit for AC-DC converter

    NASA Astrophysics Data System (ADS)

    Azazi, Haitham Z.; Ahmed, Sayed M.; Lashine, Azza E.

    2018-01-01

    This article presents a single-stage three-phase power factor correction (PFC) circuit for AC-to-DC converter using a single-switch boost regulator, leading to improve the input power factor (PF), reducing the input current harmonics and decreasing the number of required active switches. A novel PFC control strategy which is characterised as a simple and low-cost control circuit was adopted, for achieving a good dynamic performance, unity input PF, and minimising the harmonic contents of the input current, at which it can be applied to low/medium power converters. A detailed analytical, simulation and experimental studies were therefore conducted. The effectiveness of the proposed controller algorithm is validated by the simulation results, which were carried out using MATLAB/SIMULINK environment. The proposed system is built and tested in the laboratory using DSP-DS1104 digital control board for an inductive load. The results revealed that the total harmonic distortion in the supply current was very low. Finally, a good agreement between simulation and experimental results was achieved.

  15. A Proposal for Public and Private Partnership in Extension.

    PubMed

    Krell, Rayda K; Fisher, Marc L; Steffey, Kevin L

    2016-01-01

    Public funding for Extension in the United States has been decreasing for many years, but farmers' need for robust information on which to make management decisions has not diminished. The current Extension funding challenges provide motivation to explore a different model for developing and delivering extension. The private sector has partnered with the public sector to fund and conduct agricultural research, but partnering on extension delivery has occurred far less frequently. The fundamental academic strength and established Extension network of the public sector combined with the ability of the private sector to encourage and deliver practical, implementable solutions has the potential to provide measurable benefits to farmers. This paper describes the current Extension climate, presents data from a survey about Extension and industry relationships, presents case studies of successful public- and private-sector extension partnerships, and proposes a framework for evaluating the state of effective partnerships. Synergistic public-private extension efforts could ensure that farmers receive the most current and balanced information available to help with their management decisions.

  16. A Proposal for Public and Private Partnership in Extension

    PubMed Central

    Krell, Rayda K.; Fisher, Marc L.; Steffey, Kevin L.

    2016-01-01

    Public funding for Extension in the United States has been decreasing for many years, but farmers’ need for robust information on which to make management decisions has not diminished. The current Extension funding challenges provide motivation to explore a different model for developing and delivering extension. The private sector has partnered with the public sector to fund and conduct agricultural research, but partnering on extension delivery has occurred far less frequently. The fundamental academic strength and established Extension network of the public sector combined with the ability of the private sector to encourage and deliver practical, implementable solutions has the potential to provide measurable benefits to farmers. This paper describes the current Extension climate, presents data from a survey about Extension and industry relationships, presents case studies of successful public- and private-sector extension partnerships, and proposes a framework for evaluating the state of effective partnerships. Synergistic public–private extension efforts could ensure that farmers receive the most current and balanced information available to help with their management decisions. PMID:26949567

  17. A study on the influence of corona on currents and electromagnetic fields predicted by a nonlinear lightning return-stroke model

    NASA Astrophysics Data System (ADS)

    De Conti, Alberto; Silveira, Fernando H.; Visacro, Silvério

    2014-05-01

    This paper investigates the influence of corona on currents and electromagnetic fields predicted by a return-stroke model that represents the lightning channel as a nonuniform transmission line with time-varying (nonlinear) resistance. The corona model used in this paper allows the calculation of corona currents as a function of the radial electric field in the vicinity of the channel. A parametric study is presented to investigate the influence of corona parameters, such as the breakdown electric field and the critical electric field for the stable propagation of streamers, on predicted currents and electromagnetic fields. The results show that, regardless of the assumed corona parameters, the incorporation of corona into the nonuniform and nonlinear transmission line model under investigation modifies the model predictions so that they consistently reproduce most of the typical features of experimentally observed lightning electromagnetic fields and return-stroke speed profiles. In particular, it is shown that the proposed model leads to close vertical electric fields presenting waveforms, amplitudes, and decay with distance in good agreement with dart leader electric field changes measured in triggered lightning experiments. A comparison with popular engineering return-stroke models further confirms the model's ability to predict consistent electric field waveforms in the close vicinity of the channel. Some differences observed in the field amplitudes calculated with the different models can be related to the fact that current distortion, while present in the proposed model, is ultimately neglected in the considered engineering return-stroke models.

  18. Observer-based higher order sliding mode control of power factor in three-phase AC/DC converter for hybrid electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Liu, Jianxing; Laghrouche, Salah; Wack, Maxime

    2014-06-01

    In this paper, a full-bridge boost power converter topology is studied for power factor control, using output higher order sliding mode control. The AC/DC converters are used for charging the battery and super-capacitor in hybrid electric vehicles from the utility. The proposed control forces the input currents to track the desired values, which can control the output voltage while keeping the power factor close to one. Super-twisting sliding mode observer is employed to estimate the input currents and load resistance only from the measurement of output voltage. Lyapunov analysis shows the asymptotic convergence of the closed-loop system to zero. Multi-rate simulation illustrates the effectiveness and robustness of the proposed controller in the presence of measurement noise.

  19. Superconducting-circuit quantum heat engine with frequency resolved thermal baths

    NASA Astrophysics Data System (ADS)

    Hofer, Patrick P.; Souquet, Jean-René; Clerk, Aashish A.

    The study of quantum heat engines promises to unravel deep, fundamental concepts in quantum thermodynamics. With this in mind, we propose a novel, realistic device that efficiently converts heat into work while maintaining reasonably large output powers. The key concept in our proposal is a highly peaked spectral density in both the thermal baths as well as the working fluid. This allows for a complete separation of the heat current from the working fluid. In our setup, Cooper pairs tunnelling across a Josephson junction serve as the the working fluid, while two resonant cavities coupled to the junction act as frequency-resolved thermal baths. The device is operated such that a heat flux carried entirely by the photons induces an electrical current against a voltage bias, providing work.

  20. Study on Control Scheme for the Inverters in Low Voltage Microgrid with Nonlinear Loads

    NASA Astrophysics Data System (ADS)

    Xu, Jiqiang; Lu, Wenzhou; Wu, Lei

    2017-05-01

    There are a lot of nonlinear loads in real low voltage microgrid system. It will cause serious output voltage and grid current harmonic distortions problems in island and grid-connected modes, respectively. To solve this problem, this paper proposes a droop control scheme with quasi-proportion and resonant (quasi-PR) controller based on αβ stationary reference frame to make microgrid smoothly switch between grid-connected and island modes without changing control method. Moreover, in island mode, not only stable output voltage and frequency, but also reduced output voltage harmonics with added nonlinear loads can be achieved; In grid-connected mode, not only constant power, but also reduced grid current harmonics can be achieved. Simulation results verify the effectiveness of the proposed control scheme.

  1. Spatial-time-state fusion algorithm for defect detection through eddy current pulsed thermography

    NASA Astrophysics Data System (ADS)

    Xiao, Xiang; Gao, Bin; Woo, Wai Lok; Tian, Gui Yun; Xiao, Xiao Ting

    2018-05-01

    Eddy Current Pulsed Thermography (ECPT) has received extensive attention due to its high sensitive of detectability on surface and subsurface cracks. However, it remains as a difficult challenge in unsupervised detection as to identify defects without knowing any prior knowledge. This paper presents a spatial-time-state features fusion algorithm to obtain fully profile of the defects by directional scanning. The proposed method is intended to conduct features extraction by using independent component analysis (ICA) and automatic features selection embedding genetic algorithm. Finally, the optimal feature of each step is fused to obtain defects reconstruction by applying common orthogonal basis extraction (COBE) method. Experiments have been conducted to validate the study and verify the efficacy of the proposed method on blind defect detection.

  2. PSF mapping-based correction of eddy-current-induced distortions in diffusion-weighted echo-planar imaging.

    PubMed

    In, Myung-Ho; Posnansky, Oleg; Speck, Oliver

    2016-05-01

    To accurately correct diffusion-encoding direction-dependent eddy-current-induced geometric distortions in diffusion-weighted echo-planar imaging (DW-EPI) and to minimize the calibration time at 7 Tesla (T). A point spread function (PSF) mapping based eddy-current calibration method is newly presented to determine eddy-current-induced geometric distortions even including nonlinear eddy-current effects within the readout acquisition window. To evaluate the temporal stability of eddy-current maps, calibration was performed four times within 3 months. Furthermore, spatial variations of measured eddy-current maps versus their linear superposition were investigated to enable correction in DW-EPIs with arbitrary diffusion directions without direct calibration. For comparison, an image-based eddy-current correction method was additionally applied. Finally, this method was combined with a PSF-based susceptibility-induced distortion correction approach proposed previously to correct both susceptibility and eddy-current-induced distortions in DW-EPIs. Very fast eddy-current calibration in a three-dimensional volume is possible with the proposed method. The measured eddy-current maps are very stable over time and very similar maps can be obtained by linear superposition of principal-axes eddy-current maps. High resolution in vivo brain results demonstrate that the proposed method allows more efficient eddy-current correction than the image-based method. The combination of both PSF-based approaches allows distortion-free images, which permit reliable analysis in diffusion tensor imaging applications at 7T. © 2015 Wiley Periodicals, Inc.

  3. 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.

  4. New PMOS LTPS TFT pixel for AMOLED to suppress the hysteresis effect on OLED current by employing a reset voltage driving

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hoon; Park, Sang-Geun; Han, Sang-Myeon; Han, Min-Koo; Park, Kee-Chan

    2008-03-01

    New PMOS LTPS (low temperature polycrystalline silicon)-thin film transistor (TFT) pixel circuit, which can suppress an OLED current error caused by the hysteresis of LTPS-TFT for active matrix organic light emitting diode (AMOLED) display, is proposed and fabricated. The proposed pixel circuit employs a reset voltage driving so that the sweep direction of gate voltage in the current driving TFT is not altered by the gate voltage in the previous frame. Our experimental results show that OLED current error of the proposed pixel is successfully suppressed because a reset voltage can enable the starting gate voltage for a desired one not to be varied, while that of the conventional 2-TFT pixel exceeds over 15% due to the hysteresis of LTPS-TFT.

  5. Fretting wear behaviors of a dual-cooled nuclear fuel rod under a simulated rod vibration

    NASA Astrophysics Data System (ADS)

    Lee, Young-Ho; Kim, Hyung-Kyu; Kang, Heung-Seok; Yoon, Kyung-Ho; Kim, Jae-Yong; Lee, Kang-Hee

    2012-06-01

    Recently, a dual-cooled fuel (i.e., annular fuel) that is compatible with current operating PWR plants has been proposed in order to realize both a considerable amount of power uprating and an increase of safety margins. As the design concept should be compatible with current operating PWR plants, however, it shows a narrow gap between the fuel rods when compared with current solid nuclear fuel arrays and needs to modify the spacer grid shapes and their positions. In this study, fretting wear tests have been performed to evaluate the wear resistance of a dual-cooled fuel by using a proposed spring and dimple of spacer grids that have a cantilever type and hemispherical shape, respectively. As a result, the wear volume of the spring specimen gradually increases as the contact condition is changed from a certain gap, just contact to positive force. However, in the dimple specimen, just contact condition shows a large wear volume. In addition, a circular rod motion at upper region of contact surface is gradually increased and its diametric size depends on the wear depth increase. Based on the test results, the fretting wear resistance of the proposed spring and dimple is analyzed by comparing the wear measurement results and rod motion in detail.

  6. Integrating technology education concepts into China's educational system

    NASA Astrophysics Data System (ADS)

    Yang, Faxian

    The problem of this study was to develop a strategy for integrating technology education concepts within the Chinese mathematics and science curricula. The researcher used a case study as the basic methodology. It included three methods for collecting data: literature review, field study in junior and senior secondary schools in America and China, and interviews with experienced educators who were familiar with the status of technology education programs in the selected countries. The data came from the following areas: Japan, Taiwan, the United Kingdom, China, and five states in the United States: Illinois, Iowa, Maryland, Massachusetts, and New York. The researcher summarized each state and country's educational data, identified the advantages and disadvantages of their current technology education program, and identified the major concepts within each program. The process determined that identified concepts would be readily acceptable into the current Chinese educational system. Modernization of, industry, agriculture, science and technology, and defense have been recent objectives of the Chinese government. Therefore, Chinese understanding of technology, or technology education, became important for the country. However, traditional thought and culture curb the implementation of technology education within China's current education system. The proposed solution was to integrate technology education concepts into China's mathematics and science curricula. The purpose of the integration was to put new thoughts and methods into the current educational structure. It was concluded that the proposed model and interventions would allow Chinese educators to carry out the integration into China's education system.

  7. Dual optimization method of radiofrequency and quasistatic field simulations for reduction of eddy currents generated on 7T radiofrequency coil shielding.

    PubMed

    Zhao, Yujuan; Zhao, Tiejun; Raval, Shailesh B; Krishnamurthy, Narayanan; Zheng, Hai; Harris, Chad T; Handler, William B; Chronik, Blaine A; Ibrahim, Tamer S

    2015-11-01

    To optimize the design of radiofrequency (RF) shielding of transmit coils at 7T and reduce eddy currents generated on the RF shielding when imaging with rapid gradient waveforms. One set of a four-element, 2 × 2 Tic-Tac-Toe head coil structure was selected and constructed to study eddy currents on the RF coil shielding. The generated eddy currents were quantitatively studied in the time and frequency domains. The RF characteristics were studied using the finite difference time domain method. Five different kinds of RF shielding were tested on a 7T MRI scanner with phantoms and in vivo human subjects. The eddy current simulation method was verified by the measurement results. Eddy currents induced by solid/intact and simple-structured slotted RF shielding significantly distorted the gradient fields. Echo-planar images, B1+ maps, and S matrix measurements verified that the proposed slot pattern suppressed the eddy currents while maintaining the RF characteristics of the transmit coil. The presented dual-optimization method could be used to design RF shielding and reduce the gradient field-induced eddy currents while maintaining the RF characteristics of the transmit coil. © 2014 Wiley Periodicals, Inc.

  8. SparseCT: interrupted-beam acquisition and sparse reconstruction for radiation dose reduction

    NASA Astrophysics Data System (ADS)

    Koesters, Thomas; Knoll, Florian; Sodickson, Aaron; Sodickson, Daniel K.; Otazo, Ricardo

    2017-03-01

    State-of-the-art low-dose CT methods reduce the x-ray tube current and use iterative reconstruction methods to denoise the resulting images. However, due to compromises between denoising and image quality, only moderate dose reductions up to 30-40% are accepted in clinical practice. An alternative approach is to reduce the number of x-ray projections and use compressed sensing to reconstruct the full-tube-current undersampled data. This idea was recognized in the early days of compressed sensing and proposals for CT dose reduction appeared soon afterwards. However, no practical means of undersampling has yet been demonstrated in the challenging environment of a rapidly rotating CT gantry. In this work, we propose a moving multislit collimator as a practical incoherent undersampling scheme for compressed sensing CT and evaluate its application for radiation dose reduction. The proposed collimator is composed of narrow slits and moves linearly along the slice dimension (z), to interrupt the incident beam in different slices for each x-ray tube angle (θ). The reduced projection dataset is then reconstructed using a sparse approach, where 3D image gradients are employed to enforce sparsity. The effects of the collimator slits on the beam profile were measured and represented as a continuous slice profile. SparseCT was tested using retrospective undersampling and compared against commercial current-reduction techniques on phantoms and in vivo studies. Initial results suggest that SparseCT may enable higher performance than current-reduction, particularly for high dose reduction factors.

  9. Spin-dependent heat and thermoelectric currents in a Rashba ring coupled to a photon cavity

    NASA Astrophysics Data System (ADS)

    Abdullah, Nzar Rauf; Tang, Chi-Shung; Manolescu, Andrei; Gudmundsson, Vidar

    2018-01-01

    Spin-dependent heat and thermoelectric currents in a quantum ring with Rashba spin-orbit interaction placed in a photon cavity are theoretically calculated. The quantum ring is coupled to two external leads with different temperatures. In a resonant regime, with the ring structure in resonance with the photon field, the heat and the thermoelectric currents can be controlled by the Rashba spin-orbit interaction. The heat current is suppressed in the presence of the photon field due to contribution of the two-electron and photon replica states to the transport while the thermoelectric current is not sensitive to changes in parameters of the photon field. Our study opens a possibility to use the proposed interferometric device as a tunable heat current generator in the cavity photon field.

  10. Slotting optimization of automated storage and retrieval system (AS/RS) for efficient delivery of parts in an assembly shop using genetic algorithm: A case Study

    NASA Astrophysics Data System (ADS)

    Yue, L.; Guan, Z.; He, C.; Luo, D.; Saif, U.

    2017-06-01

    In recent years, the competitive pressure on manufacturing companies shifted them from mass production to mass customization to produce large variety of products. It is a great challenge for companies nowadays to produce customized mixed flow mode of production to meet customized demand on time. Due to large variety of products, the storage system to deliver variety of products to production lines influences on the timely production of variety of products, as investigated from by simulation study of an inefficient storage system of a real Company, in the current research. Therefore, current research proposed a slotting optimization model with mixed model sequence to assemble in consideration of the final flow lines to optimize whole automated storage and retrieval system (AS/RS) and distribution system in the case company. Current research is aimed to minimize vertical height of centre of gravity of AS/RS and total time spent for taking the materials out from the AS/RS simultaneously. Genetic algorithm is adopted to solve the proposed problem and computational result shows significant improvement in stability and efficiency of AS/RS as compared to the existing method used in the case company.

  11. Pixel structures to compensate nonuniform threshold voltage and mobility of polycrystalline silicon thin-film transistors using subthreshold current for large-size active matrix organic light-emitting diode displays

    NASA Astrophysics Data System (ADS)

    Na, Jun-Seok; Kwon, Oh-Kyong

    2014-01-01

    We propose pixel structures for large-size and high-resolution active matrix organic light-emitting diode (AMOLED) displays using a polycrystalline silicon (poly-Si) thin-film transistor (TFT) backplane. The proposed pixel structures compensate the variations of the threshold voltage and mobility of the driving TFT using the subthreshold current. The simulated results show that the emission current error of the proposed pixel structure B ranges from -2.25 to 2.02 least significant bit (LSB) when the variations of the threshold voltage and mobility of the driving TFT are ±0.5 V and ±10%, respectively.

  12. An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters

    PubMed Central

    Min, Run; Chen, Chen; Zhang, Xiaodong; Zou, Xuecheng; Tong, Qiaoling; Zhang, Qiao

    2014-01-01

    In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally. PMID:24854061

  13. A layman's guide to the U.S. health care system

    PubMed Central

    De Lew, Nancy; Greenberg, George; Kinchen, Kraig

    1992-01-01

    This article provides an overview of the U.S. health care system and recent proposals for health system reform. Prepared for a 15-nation comparative study for the Organization for Economic Cooperation and Development (OECD), the article summarizes descriptive data on the financing, utilization, access, and supply of U.S. health services; analyzes health system cost growth and trends; reviews health reforms adopted in the 1980s; and discusses proposals in the current health system reform debate. PMID:10124436

  14. Using chaotic artificial neural networks to model memory in the brain

    NASA Astrophysics Data System (ADS)

    Aram, Zainab; Jafari, Sajad; Ma, Jun; Sprott, Julien C.; Zendehrouh, Sareh; Pham, Viet-Thanh

    2017-03-01

    In the current study, a novel model for human memory is proposed based on the chaotic dynamics of artificial neural networks. This new model explains a biological fact about memory which is not yet explained by any other model: There are theories that the brain normally works in a chaotic mode, while during attention it shows ordered behavior. This model uses the periodic windows observed in a previously proposed model for the brain to store and then recollect the information.

  15. Fast Ss-Ilm a Computationally Efficient Algorithm to Discover Socially Important Locations

    NASA Astrophysics Data System (ADS)

    Dokuz, A. S.; Celik, M.

    2017-11-01

    Socially important locations are places which are frequently visited by social media users in their social media lifetime. Discovering socially important locations provide several valuable information about user behaviours on social media networking sites. However, discovering socially important locations are challenging due to data volume and dimensions, spatial and temporal calculations, location sparseness in social media datasets, and inefficiency of current algorithms. In the literature, several studies are conducted to discover important locations, however, the proposed approaches do not work in computationally efficient manner. In this study, we propose Fast SS-ILM algorithm by modifying the algorithm of SS-ILM to mine socially important locations efficiently. Experimental results show that proposed Fast SS-ILM algorithm decreases execution time of socially important locations discovery process up to 20 %.

  16. Design of a Programmable Gain, Temperature Compensated Current-Input Current-Output CMOS Logarithmic Amplifier.

    PubMed

    Ming Gu; Chakrabartty, Shantanu

    2014-06-01

    This paper presents the design of a programmable gain, temperature compensated, current-mode CMOS logarithmic amplifier that can be used for biomedical signal processing. Unlike conventional logarithmic amplifiers that use a transimpedance technique to generate a voltage signal as a logarithmic function of the input current, the proposed approach directly produces a current output as a logarithmic function of the input current. Also, unlike a conventional transimpedance amplifier the gain of the proposed logarithmic amplifier can be programmed using floating-gate trimming circuits. The synthesis of the proposed circuit is based on the Hart's extended translinear principle which involves embedding a floating-voltage source and a linear resistive element within a translinear loop. Temperature compensation is then achieved using a translinear-based resistive cancelation technique. Measured results from prototypes fabricated in a 0.5 μm CMOS process show that the amplifier has an input dynamic range of 120 dB and a temperature sensitivity of 230 ppm/°C (27 °C- 57°C), while consuming less than 100 nW of power.

  17. Forest resource inventory assessment in Gunung Rara Forest Reserve, Sabah, using stratified field sampling

    Treesearch

    Kamaruzaman Jusoff

    2000-01-01

    The objective of this paper is to assess the current timber volume by stratified sampling on a proposed plantation area. The study area is located in Gunung Rara Forest Reserve in the district of Tawau, Sabah, Malaysia.

  18. Development and proposed implementation of a field permeability test for a asphalt concrete.

    DOT National Transportation Integrated Search

    2001-07-01

    The objectives of this study were as follows: : 1) To review research performed by others and determine the state-of-the-art of field permeability measurements; : 2) To review current laboratory permeability testing devices and their testing procedur...

  19. Implications of Metaphors in Defining Technical Communication.

    ERIC Educational Resources Information Center

    Beck, Charles E.

    1991-01-01

    Identifies four metaphors that appear dominant in current studies in the field of technical communication: transmitter, channel, balance, and bridge. Suggests limitations upon each of the metaphors. Discusses the alternative metaphors of lock, translator, transformer, synthesizer, conductor, and orchestrator. Proposes orchestration as a fruitful…

  20. Early and Late Retirement Exits

    ERIC Educational Resources Information Center

    Brougham, Ruby R.; Walsh, David A.

    2009-01-01

    The current study proposes that personal need fulfillment (relatedness, generativity, identity, growth, and finances) predicts early and late retirement intentions. The personal needs of 160 full-time older employees were measured by personal goals, job satisfactions, job characteristics, and intrinsic motivation. Results suggest that the personal…

  1. Novel δ-doped partially insulated junctionless transistor for mixed signal integrated circuits

    NASA Astrophysics Data System (ADS)

    Patil, Ganesh C.; Bonge, Vijaysinh H.; Malode, Mayur M.; Jain, Rahul G.

    2016-02-01

    In this paper, δ-doped partially insulated junctionless transistor (δ-Pi-OXJLT) has been proposed which shows that, employing highly doped δ-region below the channel not only reduces the off-state leakage current (IOFF) and short channel effects (SCEs) but also reduce the requirements of scaling channel thickness of junctionless transistor (JLT). The comparative analysis of digital and analog circuit performance of proposed δ-Pi-OXJLT, bulk planar (BP) JLT and silicon-on-insulator (SOI) JLT has also been carried out. The digital parameters analyzed in this work are, on-state drive current (ION), IOFF, ION/IOFF ratio, static power dissipation (PSTAT) whereas the analog parameters analyzed includes, transconductance (GM), transconductance generation factor (GM/IDS), intrinsic gain (GMRO) and cut-off frequency (fT) of the devices. In addition, scaling behavior of the devices is studied for various channel lengths by using the parameters such as drain induced barrier lowering (DIBL) and sub-threshold swing (SS). It has been found that, the proposed δ-Pi-OXJLT shows significant reduction in IOFF, DIBL and SS over BPJLT and SOIJLT devices. Further, ION and ION/IOFF ratio in the case of proposed δ-Pi-OXJLT also improves over the BPJLT device. Furthermore, the improvement in analog figures of merit, GM, GM/IDS, GMRO and fT in the case of proposed δ-Pi-OXJLT clearly shows that the proposed δ-Pi-OXJLT is the promising device for mixed signal integrated circuits.

  2. 78 FR 54920 - Agency Information Collection Activities; Proposed Collection; Revision of a Currently Approved...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-06

    ... Activities; Proposed Collection; Revision of a Currently Approved Collection; Comment Requested: Deaths in... facility level, which will better inform the Deaths in Custody Reporting Program (DCRP) and other BJS...) The title of the Form/Collection: Deaths in Custody Reporting Program. (3) The agency form number, if...

  3. 76 FR 81421 - Eligible Obligations, Charitable Contributions, Nonmember Deposits, Fixed Assets, Investments...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-28

    ... will have no negative impact on these FCUs. The proposed rule also removes the automatic exemption from... proposed change. RegFlex FCUs currently operating under the automatic exemption criteria for a RegFlex... not meet the standards for automatic qualification will now, like current non-RegFlex FCUs, have...

  4. 78 FR 69614 - Home Improvements and Structural Alterations (HISA) Benefits Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... proposes new practices and policies related to the HISA benefits program and, therefore, this proposed rule... for construction projects. In practice, it is not uncommon for bids to come in at or above the maximum... currently administered, we do not further address current practice in this rulemaking. 17.3100 Purpose and...

  5. 75 FR 76473 - Agency Information Collection Activities: Proposed Collection: Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... technology. Proposed Project: Data Collection Tool for Rural Health Community-Based Grant Programs (OMB No... based on the feedback received from grantees and to reflect ORHP and HRSA's current priorities and... collection and analysis in an effort to strengthen the value of the data collection tool. There are currently...

  6. Using Wikipedia to Enhance Student Learning: A Case Study in Economics

    ERIC Educational Resources Information Center

    Freire, Tiago; Li, Jingping

    2016-01-01

    Currently, there is widespread interest in how Web 2.0 tools can be used to improve students' learning experiences. Previous studies have focused either on the advantages of wikis or on concerns over the use of Wikipedia. In this study, we propose to use Wikipedia as a classroom wiki. In doing so, we discuss how students can improve their standard…

  7. Proposal and Development of a High Voltage Variable Frequency Alternating Current Power System for Hybrid Electric Aircraft

    NASA Technical Reports Server (NTRS)

    Sadey, David J.; Taylor, Linda M.; Beach, Raymond F.

    2017-01-01

    The development of ultra-efficient commercial vehicles and the transition to low-carbon emission propulsion are seen as strategic thrust paths within NASA Aeronautics. A critical enabler to these paths comes in the form of hybrid electric propulsion systems. For megawatt-class systems, the best power system topology for these hybrid electric propulsion systems is debatable. Current proposals within NASA and the Aero community suggest using a combination of alternating current (AC) and direct current (DC) for power generation, transmission, and distribution. This paper proposes an alternative to the current thought model through the use of a primarily high voltage AC power system, supported by the Convergent Aeronautics Solutions (CAS) Project. This system relies heavily on the use of doubly-fed induction machines (DFIMs), which provide high power densities, minimal power conversion, and variable speed operation. The paper presents background on the activity along with the system architecture, development status, and preliminary results.

  8. An Improved Harmonic Current Detection Method Based on Parallel Active Power Filter

    NASA Astrophysics Data System (ADS)

    Zeng, Zhiwu; Xie, Yunxiang; Wang, Yingpin; Guan, Yuanpeng; Li, Lanfang; Zhang, Xiaoyu

    2017-05-01

    Harmonic detection technology plays an important role in the applications of active power filter. The accuracy and real-time performance of harmonic detection are the precondition to ensure the compensation performance of Active Power Filter (APF). This paper proposed an improved instantaneous reactive power harmonic current detection algorithm. The algorithm uses an improved ip -iq algorithm which is combined with the moving average value filter. The proposed ip -iq algorithm can remove the αβ and dq coordinate transformation, decreasing the cost of calculation, simplifying the extraction process of fundamental components of load currents, and improving the detection speed. The traditional low-pass filter is replaced by the moving average filter, detecting the harmonic currents more precisely and quickly. Compared with the traditional algorithm, the THD (Total Harmonic Distortion) of the grid currents is reduced from 4.41% to 3.89% for the simulations and from 8.50% to 4.37% for the experiments after the improvement. The results show the proposed algorithm is more accurate and efficient.

  9. Improvement of automatic control system for high-speed current collectors

    NASA Astrophysics Data System (ADS)

    Sidorov, O. A.; Goryunov, V. N.; Golubkov, A. S.

    2018-01-01

    The article considers the ways of regulation of pantographs to provide quality and reliability of current collection at high speeds. To assess impact of regulation was proposed integral criterion of the quality of current collection, taking into account efficiency and reliability of operation of the pantograph. The study was carried out using mathematical model of interaction of pantograph and catenary system, allowing to assess contact force and intensity of arcing at the contact zone at different movement speeds. The simulation results allowed us to estimate the efficiency of different methods of regulation of pantographs and determine the best option.

  10. Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity

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

    Huang, H. B., E-mail: houbinghuang@gmail.com; Department of Physics, University of Science and Technology Beijing, Beijing 100083; Hu, J. M.

    2014-09-22

    Effect of substrate misfit strain on current-induced in-plane magnetization reversal in CoFeB-MgO based magnetic tunnel junctions is investigated by combining micromagnetic simulations with phase-field microelasticity theory. It is found that the critical current density for in-plane magnetization reversal decreases dramatically with an increasing substrate strain, since the effective elastic field can drag the magnetization to one of the four in-plane diagonal directions. A potential strain-assisted multilevel bit spin transfer magnetization switching device using substrate misfit strain is also proposed.

  11. Digitally Controllable Current Amplifier and Current Conveyors in Practical Application of Controllable Frequency Filter

    NASA Astrophysics Data System (ADS)

    Polak, Josef; Jerabek, Jan; Langhammer, Lukas; Sotner, Roman; Dvorak, Jan; Panek, David

    2016-07-01

    This paper presents the simulations results in comparison with the measured results of the practical realization of the multifunctional second order frequency filter with a Digitally Adjustable Current Amplifier (DACA) and two Dual-Output Controllable Current Conveyors (CCCII +/-). This filter is designed for use in current mode. The filter was designed of the single input multiple outputs (SIMO) type, therefore it has only one input and three outputs with individual filtering functions. DACA element used in a newly proposed circuit is present in form of an integrated chip and the current conveyors are implemented using the Universal Current Conveyor (UCC) chip with designation UCC-N1B. Proposed frequency filter enables independent control of the pole frequency using parameters of two current conveyors and also independent control of the quality factor by change of a current gain of DACA.

  12. Determination of torque speed current characteristics of a brushless DC motor by utilizing back-EMF of non-energized phase

    NASA Astrophysics Data System (ADS)

    Jang, G. H.; Yeom, J. H.; Kim, M. G.

    2007-03-01

    This paper presents a method to determine the torque constant and the torque-speed-current characteristics of a brushless DC (BLDC) motor by utilizing back-EMF variation of nonenergized phase. It also develops a BLDC motor controller with a digital signal processor (DSP) to monitor its current, voltage and speed in real time. Torque-speed-current characteristics of a BLDC motor are determined by using the proposed method and the developed controller. They are compared with the torque-speed-current characteristics measured by dynamometer experimentally. This research shows that the proposed method is an effective method to determine the torque constant and the torque-speed-current characteristics of the BLDC motor without using dynamometer.

  13. Detecting associated single-nucleotide polymorphisms on the X chromosome in case control genome-wide association studies.

    PubMed

    Chen, Zhongxue; Ng, Hon Keung Tony; Li, Jing; Liu, Qingzhong; Huang, Hanwen

    2017-04-01

    In the past decade, hundreds of genome-wide association studies have been conducted to detect the significant single-nucleotide polymorphisms that are associated with certain diseases. However, most of the data from the X chromosome were not analyzed and only a few significant associated single-nucleotide polymorphisms from the X chromosome have been identified from genome-wide association studies. This is mainly due to the lack of powerful statistical tests. In this paper, we propose a novel statistical approach that combines the information of single-nucleotide polymorphisms on the X chromosome from both males and females in an efficient way. The proposed approach avoids the need of making strong assumptions about the underlying genetic models. Our proposed statistical test is a robust method that only makes the assumption that the risk allele is the same for both females and males if the single-nucleotide polymorphism is associated with the disease for both genders. Through simulation study and a real data application, we show that the proposed procedure is robust and have excellent performance compared to existing methods. We expect that many more associated single-nucleotide polymorphisms on the X chromosome will be identified if the proposed approach is applied to current available genome-wide association studies data.

  14. Potentiometric determination of trypsin using a polymeric membrane polycation-sensitive electrode based on current-controlled reagent delivery.

    PubMed

    Chen, Yan; Ding, Jiawang; Qin, Wei

    2012-12-01

    A potentiometric biosensor for the determination of trypsin is described based on current-controlled reagent delivery. A polymeric membrane protamine-sensitive electrode with dinonylnaphthalene sulfonate as cation exchanger is used for in situ generation of protamine. Diffusion of protamine across the polymeric membrane can be controlled precisely by applying an external current. The hydrolysis catalyzed with trypsin in sample solution decreases the concentration of free protamine released at the sample-membrane interface and facilitates the stripping of protamine out of the membrane surface via the ion-exchange process with sodium ions from the sample solution, thus decreasing the membrane potential, by which the protease can be sensed potentiometrically. The influences of anodic current amplitude, current pulse duration and protamine concentration in the inner filling solution on the membrane potential response have been studied. Under optimum conditions, the proposed protamine-sensitive electrode is useful for continuous and reversible detection of trypsin over the concentration range of 0.5-5UmL(-1) with a detection limit of 0.3UmL(-1). The proposed detection strategy provides a rapid and reagentless way for the detection of protease activities and offers great potential in the homogeneous immunoassays using proteases as labels. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Analysis and evalaution in the production process and equipment area of the low-cost solar array project. [including modifying gaseous diffusion and using ion implantation

    NASA Technical Reports Server (NTRS)

    Goldman, H.; Wolf, M.

    1979-01-01

    The manufacturing methods for photovoltaic solar energy utilization are assessed. Economic and technical data on the current front junction formation processes of gaseous diffusion and ion implantation are presented. Future proposals, including modifying gaseous diffusion and using ion implantation, to decrease the cost of junction formation are studied. Technology developments in current processes and an economic evaluation of the processes are included.

  16. Space Life Sciences Directorate's Position on the Physiological Effects of Exposing the Crewmemeber to Low-Voltage Electrical Hazards During Extravehicular Activity

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas; Kramer, Leonard; Mikatarian, Ron; Polk, James; Duncan, Michael; Koontz, Steven

    2010-01-01

    The models predict that, for low voltage exposures in the space suit, physiologically active current could be conducted across the crew member causing catastrophic hazards. Future work with Naval Health Research Center Detachment Directed Energy Bio-effects Laboratory is being proposed to analyze additional current paths across the human torso and upper limbs. These models may need to be verified with human studies.

  17. Assessing the Robustness of Green Infrastructure under Stochastic Design Storms and Climate Change Scenarios

    NASA Astrophysics Data System (ADS)

    Chui, T. F. M.; Yang, Y.

    2017-12-01

    Green infrastructures (GI) have been widely used to mitigate flood risk, improve surface water quality, and to restore predevelopment hydrologic regimes. Commonly-used GI include, bioretention system, porous pavement and green roof, etc. They are normally sized to fulfil different design criteria (e.g. providing certain storage depths, limiting peak surface flow rates) that are formulated for current climate conditions. While GI commonly have long lifespan, the sensitivity of their performance to climate change is however unclear. This study first proposes a method to formulate suitable design criteria to meet different management interests (e.g. different levels of first flush reduction and peak flow reduction). Then typical designs of GI are proposed. In addition, a high resolution stochastic design storm generator using copulas and random cascade model is developed, which is calibrated using recorded rainfall time series. Then, few climate change scenarios are generated by varying the duration and depth of design storms, and changing the parameters of the calibrated storm generator. Finally, the performance of GI with typical designs under the random synthesized design storms are then assessed using numerical modeling. The robustness of the designs is obtained by the comparing their performance in the future scenarios to the current one. This study overall examines the robustness of the current GI design criteria under uncertain future climate conditions, demonstrating whether current GI design criteria should be modified to account for climate change.

  18. FDA-sunlamp recommended Maximum Timer Interval And Exposure Schedule: consensus ISO/CIE dose equivalence.

    PubMed

    Dowdy, John C; Czako, Eugene A; Stepp, Michael E; Schlitt, Steven C; Bender, Gregory R; Khan, Lateef U; Shinneman, Kenneth D; Karos, Manuel G; Shepherd, James G; Sayre, Robert M

    2011-09-01

    The authors compared calculations of sunlamp maximum exposure times following current USFDA Guidance Policy on the Maximum Timer Interval and Exposure Schedule, with USFDA/CDRH proposals revising these to equivalent erythemal exposures of ISO/CIE Standard Erythema Dose (SED). In 2003, [USFDA/CDRH proposed replacing their unique CDRH/Lytle] erythema action spectrum with the ISO/CIE erythema action spectrum and revising the sunlamp maximum exposure timer to 600 J m(-2) ISO/CIE effective dose, presented as being biologically equivalent. Preliminary analysis failed to confirm said equivalence, indicating instead ∼38% increased exposure when applying these proposed revisions. To confirm and refine this finding, a collaboration of tanning bed and UV lamp manufacturers compiled 89 UV spectra representing a broad sampling of U.S. indoor tanning equipment. USFDA maximum recommended exposure time (Te) per current sunlamp guidance and CIE erythemal effectiveness per ISO/CIE standard were calculated. The CIE effective dose delivered per Te averaged 456 J(CIE) m(-2) (SD = 0.17) or ∼4.5 SED. The authors found that CDRH's proposed 600 J(CIE) m(-2) recommended maximum sunlamp exposure exceeds current Te erythemal dose by ∼33%. The current USFDA 0.75 MED initial exposure was ∼0.9 SED, consistent with 1.0 SED initial dose in existing international sunlamp standards. As no sunlamps analyzed exceeded 5 SED, a revised maximum exposure of 500 J(CIE) m(-2) (∼80% of CDRH's proposal) should be compatible with existing tanning equipment. A tanning acclimatization schedule is proposed beginning at 1 SED thrice-weekly, increasing uniformly stepwise over 4 wk to a 5 SED maximum exposure in conjunction with a tan maintenance schedule of twice-weekly 5 SED sessions, as biologically equivalent to current USFDA sunlamp policy.

  19. Current Status of Legislative Proposals on Greenhouse Gas Emissions and Alternative Energy in the U.S. Congress

    NASA Astrophysics Data System (ADS)

    Richardson, L. J.

    2007-12-01

    The 110th Congress is now beginning to grapple with the issue of human-induced climate change and what, if anything, to do about it. A number of bills are currently being considered that would limit greenhouse gas emissions using various policy mechanisms and over various time frames. With a commitment by the current Congressional leadership to pass legislation addressing global warming, and significant hurdles remaining, it promises to be an eventful fall session. I will review the current status of these legislative proposals and their prospects of becoming law.

  20. Minimization of Ohmic Losses for Domain Wall Motion in a Ferromagnetic Nanowire

    NASA Astrophysics Data System (ADS)

    Tretiakov, O. A.; Liu, Y.; Abanov, Ar.

    2010-11-01

    We study current-induced domain-wall motion in a narrow ferromagnetic wire. We propose a way to move domain walls with a resonant time-dependent current which dramatically decreases the Ohmic losses in the wire and allows driving of the domain wall with higher speed without burning the wire. For any domain-wall velocity we find the time dependence of the current needed to minimize the Ohmic losses. Below a critical domain-wall velocity specified by the parameters of the wire the minimal Ohmic losses are achieved by dc current. Furthermore, we identify the wire parameters for which the losses reduction from its dc value is the most dramatic.

  1. Limitations Of The Current State Space Modelling Approach In Multistage Machining Processes Due To Operation Variations

    NASA Astrophysics Data System (ADS)

    Abellán-Nebot, J. V.; Liu, J.; Romero, F.

    2009-11-01

    The State Space modelling approach has been recently proposed as an engineering-driven technique for part quality prediction in Multistage Machining Processes (MMP). Current State Space models incorporate fixture and datum variations in the multi-stage variation propagation, without explicitly considering common operation variations such as machine-tool thermal distortions, cutting-tool wear, cutting-tool deflections, etc. This paper shows the limitations of the current State Space model through an experimental case study where the effect of the spindle thermal expansion, cutting-tool flank wear and locator errors are introduced. The paper also discusses the extension of the current State Space model to include operation variations and its potential benefits.

  2. Revisiting Antipsychotic-induced Akathisia: Current Issues and Prospective Challenges

    PubMed Central

    Salem, Haitham; Nagpal, Caesa; Pigott, Teresa; Teixeira, Antonio Lucio

    2017-01-01

    Background: Akathisia continues to be a significant challenge in current neurological and psychiatric practice. Prompt and accurate detection is often difficult and there is a lack of consensus concerning the neurobiological basis of akathisia. No definitive treatment has been established for akathisia despite numerous preclinical and clinical studies. Method: We reviewed antipsychotic-induced akathisia including its clinical presentation, proposed underlying pathophysiology, current and under investigation therapeutic strategies. Conclusion: Despite the initial promise that second generation antipsychotics would be devoid of akathisia effects, this has not been confirmed. Currently, there are limited therapeutic options for the clinical practice and the evidence supporting the most widely used treatments (beta blockers, anticholinergic drugs) is still absent or inconsistent. PMID:27928948

  3. Analytical modeling and analysis of magnetic field and torque for novel axial flux eddy current couplers with PM excitation

    NASA Astrophysics Data System (ADS)

    Li, Zhao; Wang, Dazhi; Zheng, Di; Yu, Linxin

    2017-10-01

    Rotational permanent magnet eddy current couplers are promising devices for torque and speed transmission without any mechanical contact. In this study, flux-concentration disk-type permanent magnet eddy current couplers with double conductor rotor are investigated. Given the drawback of the accurate three-dimensional finite element method, this paper proposes a mixed two-dimensional analytical modeling approach. Based on this approach, the closed-form expressions of magnetic field, eddy current, electromagnetic force and torque for such devices are obtained. Finally, a three-dimensional finite element method is employed to validate the analytical results. Besides, a prototype is manufactured and tested for the torque-speed characteristic.

  4. Modeling and experiments of the adhesion force distribution between particles and a surface.

    PubMed

    You, Siming; Wan, Man Pun

    2014-06-17

    Due to the existence of surface roughness in real surfaces, the adhesion force between particles and the surface where the particles are deposited exhibits certain statistical distributions. Despite the importance of adhesion force distribution in a variety of applications, the current understanding of modeling adhesion force distribution is still limited. In this work, an adhesion force distribution model based on integrating the root-mean-square (RMS) roughness distribution (i.e., the variation of RMS roughness on the surface in terms of location) into recently proposed mean adhesion force models was proposed. The integration was accomplished by statistical analysis and Monte Carlo simulation. A series of centrifuge experiments were conducted to measure the adhesion force distributions between polystyrene particles (146.1 ± 1.99 μm) and various substrates (stainless steel, aluminum and plastic, respectively). The proposed model was validated against the measured adhesion force distributions from this work and another previous study. Based on the proposed model, the effect of RMS roughness distribution on the adhesion force distribution of particles on a rough surface was explored, showing that both the median and standard deviation of adhesion force distribution could be affected by the RMS roughness distribution. The proposed model could predict both van der Waals force and capillary force distributions and consider the multiscale roughness feature, greatly extending the current capability of adhesion force distribution prediction.

  5. Economic selection indexes for Hereford and Braford cattle raised in southern Brazil.

    PubMed

    Costa, R F; Teixeira, B B M; Yokoo, M J; Cardoso, F F

    2017-07-01

    Economic selection indexes (EI) are considered the best way to select the most profitable animals for specific production systems. Nevertheless, in Brazil, few genetic evaluation programs deliver such indexes to their breeders. The aims of this study were to determine the breeding goals (BG) and economic values (EV, in US$) for typical beef cattle production systems in southern Brazil, to propose EI aimed to maximize profitability, and to compare the proposed EI with the currently used empirical index. Bioeconomic models were developed to characterize 3 typical production systems, identifying traits of economic impact and their respective EV. The first was called the calf-crop system and included the birth rate (BR), direct weaning weight (WWd), and mature cow weight (MCW) as selection goals. The second system was called the full-cycle system, and its breeding goals were BR, WWd, MCW, and carcass weight (CW). Finally, the third was called the stocking and finishing system, which had WWd and CW as breeding goals. To generate the EI, we adopted the selection criteria currently measured and used in the empirical index of PampaPlus, which is the genetic evaluation program of the Brazilian Hereford and Braford Association. The comparison between the EI and the current PampaPlus index was made by the aggregated genetic-economic gain per generation (Δ). Therefore, for each production system an index was developed using the derived economic weights, and it was compared with the current empirical index. The relative importance (RI) for BR, WWd, and MCW for the calf-crop system was 68.03%, 19.35%, and 12.62%, respectively. For the full-cycle system, the RI for BR, WWd, MCW, and CW were 69.63%, 7.31%, 5.01%, and 18.06%, respectively. For the stocking and finishing production system, the RI for WWd and CW was 34.20% and 65.80%, respectively. The Δ for the calf-crop system were US$6.12 and US$4.36, using the proposed economic and empirical indexes, respectively. Respective values were US$19.87 and US$18.22 for the full-cycle system and US$20.52 and US$18.52 in the stocking and finishing system. The efficiency of the proposed EI had low sensitivity to changes in the values of the economic and genetic parameters. The 3 EI generated higher Δ when using the proposed economic weight compared to the Δ provided by a PampaPlus index, suggesting the use of proposed EI to obtain greater economic profitability in relation to the current empirical PampaPlus index.

  6. Adaptation of superconducting fault current limiter to high-speed reclosing

    NASA Astrophysics Data System (ADS)

    Koyama, T.; Yanabu, S.

    2009-10-01

    Using a high temperature superconductor, we constructed and tested a model superconducting fault current limiter (SFCL). The superconductor might break in some cases because of its excessive generation of heat. Therefore, it is desirable to interrupt early the current that flows to superconductor. So, we proposed the SFCL using an electromagnetic repulsion switch which is composed of a superconductor, a vacuum interrupter and a by-pass coil, and its structure is simple. Duration that the current flow in the superconductor can be easily minimized to the level of less than 0.5 cycle using this equipment. On the other hand, the fault current is also easily limited by large reactance of the parallel coil. There is duty of high-speed reclosing after interrupting fault current in the electric power system. After the fault current is interrupted, the back-up breaker is re-closed within 350 ms. So, the electromagnetic repulsion switch should return to former state and the superconductor should be recovered to superconducting state before high-speed reclosing. Then, we proposed the SFCL using an electromagnetic repulsion switch which employs our new reclosing function. We also studied recovery time of the superconductor, because superconductor should be recovered to superconducting state within 350 ms. In this paper, the recovery time characteristics of the superconducting wire were investigated. Also, we combined the superconductor with the electromagnetic repulsion switch, and we did performance test. As a result, a high-speed reclosing within 350 ms was proven to be possible.

  7. Planar maneuvering control of underwater snake robots using virtual holonomic constraints.

    PubMed

    Kohl, Anna M; Kelasidi, Eleni; Mohammadi, Alireza; Maggiore, Manfredi; Pettersen, Kristin Y

    2016-11-24

    This paper investigates the problem of planar maneuvering control for bio-inspired underwater snake robots that are exposed to unknown ocean currents. The control objective is to make a neutrally buoyant snake robot which is subject to hydrodynamic forces and ocean currents converge to a desired planar path and traverse the path with a desired velocity. The proposed feedback control strategy enforces virtual constraints which encode biologically inspired gaits on the snake robot configuration. The virtual constraints, parametrized by states of dynamic compensators, are used to regulate the orientation and forward speed of the snake robot. A two-state ocean current observer based on relative velocity sensors is proposed. It enables the robot to follow the path in the presence of unknown constant ocean currents. The efficacy of the proposed control algorithm for several biologically inspired gaits is verified both in simulations for different path geometries and in experiments.

  8. Design of an ultra low power third order continuous time current mode ΣΔ modulator for WLAN applications.

    PubMed

    Behzadi, Kobra; Baghelani, Masoud

    2014-05-01

    This paper presents a third order continuous time current mode ΣΔ modulator for WLAN 802.11b standard applications. The proposed circuit utilized feedback architecture with scaled and optimized DAC coefficients. At circuit level, we propose a modified cascade current mirror integrator with reduced input impedance which results in more bandwidth and linearity and hence improves the dynamic range. Also, a very fast and precise novel dynamic latch based current comparator is introduced with low power consumption. This ultra fast comparator facilitates increasing the sampling rate toward GHz frequencies. The modulator exhibits dynamic range of more than 60 dB for 20 MHz signal bandwidth and OSR of 10 while consuming only 914 μW from 1.8 V power supply. The FoM of the modulator is calculated from two different methods, and excellent performance is achieved for proposed modulator.

  9. Design of an ultra low power third order continuous time current mode ΣΔ modulator for WLAN applications

    PubMed Central

    Behzadi, Kobra; Baghelani, Masoud

    2013-01-01

    This paper presents a third order continuous time current mode ΣΔ modulator for WLAN 802.11b standard applications. The proposed circuit utilized feedback architecture with scaled and optimized DAC coefficients. At circuit level, we propose a modified cascade current mirror integrator with reduced input impedance which results in more bandwidth and linearity and hence improves the dynamic range. Also, a very fast and precise novel dynamic latch based current comparator is introduced with low power consumption. This ultra fast comparator facilitates increasing the sampling rate toward GHz frequencies. The modulator exhibits dynamic range of more than 60 dB for 20 MHz signal bandwidth and OSR of 10 while consuming only 914 μW from 1.8 V power supply. The FoM of the modulator is calculated from two different methods, and excellent performance is achieved for proposed modulator. PMID:25685504

  10. Development of Low Parasitic Light Sensitivity and Low Dark Current 2.8 μm Global Shutter Pixel †

    PubMed Central

    Yokoyama, Toshifumi; Tsutsui, Masafumi; Suzuki, Masakatsu; Nishi, Yoshiaki; Mizuno, Ikuo; Lahav, Assaf

    2018-01-01

    We developed a low parasitic light sensitivity (PLS) and low dark current 2.8 μm global shutter pixel. We propose a new inner lens design concept to realize both low PLS and high quantum efficiency (QE). 1/PLS is 7700 and QE is 62% at a wavelength of 530 nm. We also propose a new storage-gate based memory node for low dark current. P-type implants and negative gate biasing are introduced to suppress dark current at the surface of the memory node. This memory node structure shows the world smallest dark current of 9.5 e−/s at 60 °C. PMID:29370146

  11. Development of Low Parasitic Light Sensitivity and Low Dark Current 2.8 μm Global Shutter Pixel.

    PubMed

    Yokoyama, Toshifumi; Tsutsui, Masafumi; Suzuki, Masakatsu; Nishi, Yoshiaki; Mizuno, Ikuo; Lahav, Assaf

    2018-01-25

    Abstract : We developed a low parasitic light sensitivity (PLS) and low dark current 2.8 μm global shutter pixel. We propose a new inner lens design concept to realize both low PLS and high quantum efficiency (QE). 1/PLS is 7700 and QE is 62% at a wavelength of 530 nm. We also propose a new storage-gate based memory node for low dark current. P-type implants and negative gate biasing are introduced to suppress dark current at the surface of the memory node. This memory node structure shows the world smallest dark current of 9.5 e - /s at 60 °C.

  12. Severity of Organized Item Theft in Computerized Adaptive Testing: An Empirical Study. Research Report. ETS RR-06-22

    ERIC Educational Resources Information Center

    Yi, Qing; Zhang, Jinming; Chang, Hua-Hua

    2006-01-01

    Chang and Zhang (2002, 2003) proposed several baseline criteria for assessing the severity of possible test security violations for computerized tests with high-stakes outcomes. However, these criteria were obtained from theoretical derivations that assumed uniformly randomized item selection. The current study investigated potential damage caused…

  13. A Research-Based Proposal for EFL Writing Instruction in Korean Higher Education

    ERIC Educational Resources Information Center

    Lee, Song-Eun

    2017-01-01

    Writing and its pedagogy have been underemphasized in formal school education in Korea; nevertheless, a number of studies on writing have been conducted in the English education field in Korean higher education. Among these studies, however, few have been conducted to afford a broader understanding of the current situation of English writing…

  14. Investigating the Role of Psychological Contract Breach on Career Success: Convergent Evidence from Two Longitudinal Studies

    ERIC Educational Resources Information Center

    Restubog, Simon Lloyd D.; Bordia, Prashant; Bordia, Sarbari

    2011-01-01

    The current study extends past research by examining leader-member exchange as a mediator of the relationship between employee reports of psychological contract breach and career success. In addition, we tested a competing perspective in which we proposed that performance mediators (i.e., in-role performance and organizational citizenship…

  15. Validation of the Schutte Self-Report Emotional Intelligence Scale with American College Students

    ERIC Educational Resources Information Center

    Gong, Xiaopeng; Paulson, Sharon E.

    2018-01-01

    The current study examined the factor structure of the Schutte Self-Report Emotional Intelligence (SSREI) scale with an American college sample (n = 404, 322 females, 88.9% Whites). Data were collected through an online survey, and confirmatory factor analyses were conducted to test several proposed factor models from previous studies. The results…

  16. Understanding Writing Problems in Young Children: Contributions of Cognitive Skills to the Development of Written Expression

    ERIC Educational Resources Information Center

    Childress, Amy

    2011-01-01

    While several models of adult writing have been proposed and studied, the development of writing skills in young children has only recently garnered attention. Using measures of fine-motor, language, working memory, and attention/executive functions, the current study explored motor and cognitive skills that may contribute to writing skill in…

  17. A Study of Organization and Governance of Alabama State Library Systems.

    ERIC Educational Resources Information Center

    Public Administration Service, Washington, DC.

    In order to provide the citizens of Alabama with the best possible library service for a given level of funding, this study recommends a model for the organization and funding of multi-type library cooperation in the state, based on a review of past developments and current conditions, together with proposed changes in state library legislation…

  18. The Effect of Classroom Web Applications on Teaching, Learning and Academic Performance among College of Education Female Students

    ERIC Educational Resources Information Center

    Aljraiwi, Seham Salman

    2017-01-01

    The current study proposes web applications-based learning environment to promote teaching and learning activities in the classrooms. It also helps teachers facilitate learners' contributions in the process of learning and improving their motivation and performance. The case study illustrated that female students were more interested in learning…

  19. Improving the Dissemination of United States Government Information: The Report of the Public Printer's Sales Publications Pricing Panel.

    ERIC Educational Resources Information Center

    Foss, Stuart M.

    1991-01-01

    Eleven issues were considered in study of Government Printing Office's Sales of Publications Program in areas such as pricing, marketing, program administration, and appeals of disputed prices. Sales Program study of documents pricing and government information dissemination proposes testing of alternative approaches to current pricing, increasing…

  20. Improved Diagnostic Validity of the ADOS Revised Algorithms: A Replication Study in an Independent Sample

    ERIC Educational Resources Information Center

    Oosterling, Iris; Roos, Sascha; de Bildt, Annelies; Rommelse, Nanda; de Jonge, Maretha; Visser, Janne; Lappenschaar, Martijn; Swinkels, Sophie; van der Gaag, Rutger Jan; Buitelaar, Jan

    2010-01-01

    Recently, Gotham et al. ("2007") proposed revised algorithms for the Autism Diagnostic Observation Schedule (ADOS) with improved diagnostic validity. The aim of the current study was to replicate predictive validity, factor structure, and correlations with age and verbal and nonverbal IQ of the ADOS revised algorithms for Modules 1 and 2…

  1. 75 FR 3901 - Notice of Availability of Record of Decision for the Naval Surface Warfare Center Panama City...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... NSWC PCD Study Area. The proposed action is required for the Navy to successfully meet current and..., test, and evaluate systems within the NSWC PCD Study Area. In its decision, the Navy considered... outside the U.S. or its territories under Executive Order (EO) 12114, Environmental Effects Abroad of...

  2. Resonant Hall effect under generation of a self-sustaining mode of spin current in nonmagnetic bipolar conductors with identical characters between holes and electrons

    NASA Astrophysics Data System (ADS)

    Sakai, Masamichi; Takao, Hiraku; Matsunaga, Tomoyoshi; Nishimagi, Makoto; Iizasa, Keitaro; Sakuraba, Takahito; Higuchi, Koji; Kitajima, Akira; Hasegawa, Shigehiko; Nakamura, Osamu; Kurokawa, Yuichiro; Awano, Hiroyuki

    2018-03-01

    We have proposed an enhancement mechanism of the Hall effect, the signal of which is amplified due to the generation of a sustaining mode of spin current. Our analytic derivations of the Hall resistivity revealed the conditions indispensable for the observation of the effect: (i) the presence of the transverse component of an effective electric field due to spin splitting in chemical potential in addition to the longitudinal component; (ii) the simultaneous presence of holes and electrons each having approximately the same characteristics; (iii) spin-polarized current injection from magnetized electrodes; (iv) the boundary condition for the transverse current (J c, y = 0). The model proposed in this study was experimentally verified by using van der Pauw-type Hall devices consisting of the nonmagnetic bipolar conductor YH x (x ≃ 2) and TbFeCo electrodes. Replacing Au electrodes with TbFeCo electrodes alters the Hall resistivity from the ordinary Hall effect to the anomalous Hall-like effect with an enhancement factor of approximately 50 at 4 T. We interpreted the enhancement phenomenon in terms of the present model.

  3. A methodology to investigate the intrinsic effect of the pulsed electric current during the spark plasma sintering of electrically conductive powders

    PubMed Central

    Locci, Antonio Mario; Cincotti, Alberto; Todde, Sara; Orrù, Roberto; Cao, Giacomo

    2010-01-01

    A novel methodology is proposed for investigating the effect of the pulsed electric current during the spark plasma sintering (SPS) of electrically conductive powders without potential misinterpretation of experimental results. First, ensemble configurations (geometry, size and material of the powder sample, die, plunger and spacers) are identified where the electric current is forced to flow only through either the sample or the die, so that the sample is heated either through the Joule effect or by thermal conduction, respectively. These ensemble configurations are selected using a recently proposed mathematical model of an SPS apparatus, which, once suitably modified, makes it possible to carry out detailed electrical and thermal analysis. Next, SPS experiments are conducted using the ensemble configurations theoretically identified. Using aluminum powders as a case study, we find that the temporal profiles of sample shrinkage, which indicate densification behavior, as well as the final density of the sample are clearly different when the electric current flows only through the sample or through the die containing it, whereas the temperature cycle and mechanical load are the same in both cases. PMID:27877354

  4. Dental epidemiology of military operations.

    PubMed

    Chisick, M C; King, J E

    1993-09-01

    In this paper we review studies that have been conducted on the epidemiology of oral, dental, and maxillofacial conditions during military deployments. The limitations of our current knowledge base are discussed, as is a proposed research effort to enhance the responsiveness of dental support in theaters of operation.

  5. Health hazards of ultrafine metal and metal oxide powders

    NASA Technical Reports Server (NTRS)

    Boylen, G. W., Jr.; Chamberlin, R. I.; Viles, F. J.

    1969-01-01

    Study reveals that suggested threshold limit values are from two to fifty times lower than current recommended threshold limit values. Proposed safe limits of exposure to the ultrafine dusts are based on known toxic potential of various materials as determined in particle size ranges.

  6. Current practices in pavement performance modeling project 08-03 (C07) : task 4 report final summary of findings.

    DOT National Transportation Integrated Search

    2010-02-26

    In anticipation of developing pavement performance models as part of a proposed pavement management : system, the Pennsylvania Department of Transportation (PennDOT) initiated a study in 2009 to investigate : performance modeling activities and condi...

  7. Increasing Army Supply Chain Performance: Using an Integrated End to End Metrics System

    DTIC Science & Technology

    2017-01-01

    Sched Deliver Sched Delinquent Contracts Current Metrics PQDR/SDRs Forecasting Accuracy Reliability Demand Management Asset Mgmt Strategies Pipeline...are identified and characterized by statistical analysis. The study proposed a framework and tool for inventory management based on factors such as

  8. Faculty Productivity: Practice and Policy.

    ERIC Educational Resources Information Center

    Quigley, E. James

    Information was obtained on current or recently proposed legislation, administrative regulations, policies, practices, reports or studies on any aspect of faculty productivity, faculty workload or teaching load, or faculty activity analysis. Responses were obtained from 34 states. Responses for the 14 states that provided reference material are…

  9. Technical bulletin on design and construction of crack attenuating mixes (CAM).

    DOT National Transportation Integrated Search

    2010-02-01

    The crack attenuating mix (CAM) is proposed as a thin, long-lasting, cost effective surface mix : for pavement maintenance and preservation. Developed under TxDOT research study 0-5598, : this very fine mix is designed to pass both the current Hambur...

  10. An Analysis of the President’s Budgetary Proposals for Fiscal Year 1981.

    DTIC Science & Technology

    1980-02-01

    in medical care costs. CBO projects current law program outlays to be somewhat lower than the President’s estimates in both fiscal years 1980 and 1981...examines the major features of the Administration’s revenue and spending proposals for 1981 and compares them with past trends and current laws . The effect...ADMINISTRATION’S AND CBO’S ECONOMIC FORECASTS, CALENDAR YEARS 1980 AND 1981 . . ... I TABLE 2. THE FEDERAL BUDGET OUTLOOK UNDER CBO CURRENT LAW ESTIMATE AND

  11. Divergence in Defence against Herbivores between Males and Females of Dioecious Plant Species

    PubMed Central

    Avila-Sakar, Germán; Romanow, Cora Anne

    2012-01-01

    Defensive traits may evolve differently between sexes in dioecious plant species. Our current understanding of this process hinges on a partial view of the evolution of resistance traits that may result in male-biased herbivory in dioecious populations. Here, we present a critical summary of the current state of the knowledge of herbivory in dioecious species and propose alternative evolutionary scenarios that have been neglected. These scenarios consider the potential evolutionary and functional determinants of sexual dimorphism in patterns of resource allocation to reproduction, growth, and defence. We review the evidence upon which two previous reviews of sex-biased herbivory have concluded that male-biased herbivory is a rule for dioecious species, and we caution readers about a series of shortcomings of many of these studies. Lastly, we propose a minimal standard protocol that should be followed in any studies that intend to elucidate the (co)evolution of interactions between dioecious plants and their herbivores. PMID:23320247

  12. Low-power, high-speed 1-bit inexact Full Adder cell designs applicable to low-energy image processing

    NASA Astrophysics Data System (ADS)

    Zareei, Zahra; Navi, Keivan; Keshavarziyan, Peiman

    2018-03-01

    In this paper, three novel low-power and high-speed 1-bit inexact Full Adder cell designs are presented based on current mode logic in 32 nm carbon nanotube field effect transistor technology for the first time. The circuit-level figures of merits, i.e. power, delay and power-delay product as well as application-level metric such as error distance, are considered to assess the efficiency of the proposed cells over their counterparts. The effect of voltage scaling and temperature variation on the proposed cells is studied using HSPICE tool. Moreover, using MATLAB tool, the peak signal to noise ratio of the proposed cells is evaluated in an image-processing application referred to as motion detector. Simulation results confirm the efficiency of the proposed cells.

  13. 75 FR 58462 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing of a Proposed Rule Change...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ... resting interest exceeds the Defined Limit, the Market Maker must enter new interest at a price not more than the Designated Percentage of 8% away from the NBBO (or identify to the Corporation current resting... Corporation current resting interest that satisfies the Market Maker's obligation). The Exchange proposes that...

  14. 78 FR 62787 - Self-Regulatory Organizations; Chicago Mercantile Exchange Inc.; Notice of Filing and Immediate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-22

    ... component of its current IRS margin model. The proposed change is reflected in an Advisory Notice issued to... offers clearing for a variety of swaps products under the exclusive jurisdiction of the Commodity Futures... rate swaps (``IRS''). CME proposes to make certain changes to its current IRS margin model in relation...

  15. 77 FR 56713 - Proposed Information Collection Activity: Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-13

    ... satisfaction with their current burial benefits within the National Cemetery System and what role, if any, new offerings might play in the future. DATES: Written comments and recommendations on the proposed collection...

  16. An Investigation of Proposed Techniques for Quantifying Confidence in Assurance Arguments

    NASA Technical Reports Server (NTRS)

    Graydon, Patrick J.; Holloway, C. Michael

    2016-01-01

    The use of safety cases in certification raises the question of assurance argument sufficiency and the issue of confidence (or uncertainty) in the argument's claims. Some researchers propose to model confidence quantitatively and to calculate confidence in argument conclusions. We know of little evidence to suggest that any proposed technique would deliver trustworthy results when implemented by system safety practitioners. Proponents do not usually assess the efficacy of their techniques through controlled experiment or historical study. Instead, they present an illustrative example where the calculation delivers a plausible result. In this paper, we review current proposals, claims made about them, and evidence advanced in favor of them. We then show that proposed techniques can deliver implausible results in some cases. We conclude that quantitative confidence techniques require further validation before they should be recommended as part of the basis for deciding whether an assurance argument justifies fielding a critical system.

  17. Active-Matrix Organic Light Emission Diode Pixel Circuit for Suppressing and Compensating for the Threshold Voltage Degradation of Hydrogenated Amorphous Silicon Thin Film Transistors

    NASA Astrophysics Data System (ADS)

    Shin, Hee-Sun; Lee, Won-Kyu; Park, Sang-Guen; Kuk, Seung-Hee; Han, Min-Koo

    2009-03-01

    A new hydrogenated amorphous silicon (a-Si:H) thin film transistor (TFT) pixel circuit for active-matrix organic light emission diodes (AM-OLEDs), which significantly compensates the OLED current degradation by memorizing the threshold voltage of driving TFT and suppresses the threshold voltage shift of a-Si:H TFTs by negative bias annealing, is proposed and fabricated. During the first half of each frame, the driving TFT of the proposed pixel circuit supplies current to the OLED, which is determined by modified data voltage in the compensation scheme. The proposed pixel circuit was able to compensate the threshold voltage shift of the driving TFT as well as the OLED. During the remaining half of each frame, the proposed pixel circuit induces the recovery of the threshold voltage degradation of a-Si:H TFTs owing to the negative bias annealing. The experimental results show that the proposed pixel circuit was able to successfully compensate for the OLED current degradation and suppress the threshold voltage degradation of the driving TFT.

  18. [Asperger syndrome: evolution of the concept and current clinical data].

    PubMed

    Aussilloux, C; Baghdadli, A

    2008-05-01

    Although Asperger syndrome is described by international classifications as a category of pervasive developmental disorder (PDD), its validity as a specific entity distinct from autistic disorders remains controversial. The syndrome, first described by Hans Asperger, could not be distinguished from high functioning autism (onset, symptoms, outcome...). However, international classifications propose a distinction between the two syndromes based on a delayed onset, the absence of speech delay, the presence of motor disorders and a better outcome in Asperger syndrome. This categorical differentiation is not confirmed by current studies and in the absence of biological markers, no clinical, neuropsychological or epidemiological criteria makes it possible to distinguish high functioning autism from Asperger syndrome. From a clinical perspective, it is nevertheless of interest to isolate Asperger syndrome from other autistic disorders to propose specific assessment and therapy.

  19. Convection, buoyancy or endolymph expansion: what is the actual mechanism responsible for the caloric response of semicircular canals?

    PubMed

    Valli, Paulo; Buizza, Angelo; Botta, Laura; Zucca, Giampiero; Ghezzi, Luciano; Valli, Stefano

    The mechanisms underlying caloric nystagmus are still matter of debate. The original theory proposed by Barany and more recently by Pau and Limberg suggested that convective endolymphatic currents were involved. In contrast Gentine et al. suggested that the main mechanism responsible for caloric nystagmus is buoyancy due to calorization of the endolymph, without the need of continuous convective currents. Finally, other authors (Scherer and Clarke, Arai et al.) proposed that thermal expansion or contraction of the endolymph were involved. In the present study experimental conditions have been considered able to discriminate between these different models. The experiments, were carried out on isolated labyrinth preparations of the frog. Only the predictions of the model based on buoyancy were fully consistent with the experimental results whereas those provided by the other models were not.

  20. Dual interface gratings design for absorption enhancement in thin crystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Jinqiannan; Yu, Zhongyuan; Liu, Yumin; Chai, Hongyu; Hao, Jing; Ye, Han

    2017-09-01

    We numerically study and analyze the light absorption enhancement in thin crystalline silicon solar cell with dual interface gratings. The structure combines the front dielectric nanowalls and the sinusoidal plasmonic grating at back reflector. We show that having specific interfaces with well-chosen period, fill factor and height can allow more efficient dielectric and plasmonic modes coupling into active layer and can improve the solar cell performance. For 1 μm active layer case, the optimal result for the proposed structure achieves short-circuit current of 23.6 mA/cm2, which performs over 50% better than flat solar cell structure, the short-circuit current of which is 15.5 mA/cm2. In addition, the active layer thickness and angular analysis show that the proposed structure maintains its advantage over flat structure.

  1. Externalizing disorders: cluster 5 of the proposed meta-structure for DSM-V and ICD-11.

    PubMed

    Krueger, R F; South, S C

    2009-12-01

    The extant major psychiatric classifications DSM-IV and ICD-10 are purportedly atheoretical and largely descriptive. Although this achieves good reliability, the validity of a medical diagnosis is greatly enhanced by an understanding of the etiology. In an attempt to group mental disorders on the basis of etiology, five clusters have been proposed. We consider the validity of the fifth cluster, externalizing disorders, within this proposal. We reviewed the literature in relation to 11 validating criteria proposed by the Study Group of the DSM-V Task Force, in terms of the extent to which these criteria support the idea of a coherent externalizing spectrum of disorders. This cluster distinguishes itself by the central role of disinhibitory personality in mental disorders spread throughout sections of the current classifications, including substance dependence, antisocial personality disorder and conduct disorder. Shared biomarkers, co-morbidity and course offer additional evidence for a valid cluster of externalizing disorders. Externalizing disorders meet many of the salient criteria proposed by the Study Group of the DSM-V Task Force to suggest a classification cluster.

  2. 76 FR 5580 - Eagle Crest Energy Company; Notice of Applicant-Proposed Water Pipeline Route for the Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-01

    ... Hydroelectric Project (Eagle Mountain Project). This notice describes the water supply pipeline route proposed... property that would be crossed by the proposed water supply pipeline. We are currently soliciting comments on the proposed water supply pipeline and the draft EIS. Additionally, as discussed below, we will be...

  3. Spin current and second harmonic generation in non-collinear magnetic systems: the hydrodynamic model

    NASA Astrophysics Data System (ADS)

    Karashtin, E. A.; Fraerman, A. A.

    2018-04-01

    We report a theoretical study of the second harmonic generation in a noncollinearly magnetized conductive medium with equilibrium spin current. The hydrodynamic model is used to unravel the mechanism of a novel effect of the double frequency signal generation that is attributed to the spin current. According to our calculations, this second harmonic response appears due to the ‘non-adiabatic’ spin polarization of the conduction electrons induced by the oscillations in the non-uniform magnetization forced by the electric field of the electromagnetic wave. Together with the linear velocity response this leads to the generation of the double frequency spin current. This spin current is converted to the electric current via the inverse spin Hall effect, and the double-frequency electric current emits the second harmonic radiation. Possible experiment for detection of the new second harmonic effect is proposed.

  4. Research in Distributed Real-Time Systems

    NASA Technical Reports Server (NTRS)

    Mukkamala, R.

    1997-01-01

    This document summarizes the progress we have made on our study of issues concerning the schedulability of real-time systems. Our study has produced several results in the scalability issues of distributed real-time systems. In particular, we have used our techniques to resolve schedulability issues in distributed systems with end-to-end requirements. During the next year (1997-98), we propose to extend the current work to address the modeling and workload characterization issues in distributed real-time systems. In particular, we propose to investigate the effect of different workload models and component models on the design and the subsequent performance of distributed real-time systems.

  5. Studying the Study Section: How Group Decision Making in Person and via Videoconferencing Affects the Grant Peer Review Process. WCER Working Paper No. 2015-6

    ERIC Educational Resources Information Center

    Pier, Elizabeth L.; Raclaw, Joshua; Nathan, Mitchell J.; Kaatz, Anna; Carnes, Molly; Ford, Cecilia E.

    2015-01-01

    Grant peer review is a foundational component of scientific research. In the context of grant review meetings, the review process is a collaborative, socially mediated, locally constructed decision-making task. The current study examines how collaborative discussion affects reviewers' scores of grant proposals, how different review panels score…

  6. Ultra-High Intensity Magnetic Field Generation in Dense Plasma

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

    Fisch, Nathaniel J.

    2014-01-08

    The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereas the efficient generation of electric current in low-­energy-­density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-­energy-­density plasma the ideas for steady-­state current drive developed for low-­energy-­density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-­energy-­density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new formsmore » of current drive in regimes appropriate for new fusion concepts.« less

  7. Proposed modification to the specification for dry heat microbial reduction of spacecraft hardware for future US missions

    NASA Astrophysics Data System (ADS)

    James; Spry, A.; Beaudet, Robert; Schubert, Wayne

    Dry heat microbial reduction (DHMR) is the primary technique used to reduce the microbial load of spacecraft and component parts to comply with planetary protection requirements. Often, manufacturing processes involve heating flight hardware to high temperatures for purposes other than planetary protection DHMR. At present, the existing specification in NASA document NPR8020.12C, describing the process lethality on B. atrophaeus (ATCC 9372) bacterial spores, does not allow for additional planetary protection bioburden reduction credit for processing outside a narrow temperature, time and humidity window. However, recent studies (Schubert et al., COSPAR 2008) from a comprehensive multi-year laboratory research effort have generated enhanced data sets on four aspects of the current specification: time and temperature combination effects, the effect that humidity has on spore lethality, the lethality for spores with exceptionally high thermal resistance (so called "hardies"), and the extended exposure requirement for encapsulated microorganisms. This paper describes proposed modifications to the specification, based on the data set generated in the referenced study. The proposed modifications are intended to broaden the scope of the current specification while still maintaining a confident conservative interpretation of the lethality of the DHMR process on microorganisms. Potential cost and schedule benefits to future missions utilizing the revised specification will be highlighted.

  8. Integration of offshore wind farms through high voltage direct current networks

    NASA Astrophysics Data System (ADS)

    Livermore, Luke

    The integration of offshore wind farms through Multi Terminal DC (MTDC) networks into the GB network was investigated. The ability of Voltage Source Converter (VSC) High Voltage Direct Current (HVDC) to damp Subsynchronous Resonance (SSR) and ride through onshore AC faults was studied. Due to increased levels of wind generation in Scotland, substantial onshore and offshore reinforcements to the GB transmission network are proposed. Possible inland reinforcements include the use of series compensation through fixed capacitors. This potentially can lead to SSR. Offshore reinforcements are proposed by two HVDC links. In addition to its primary functions of bulk power transmission, a HVDC link can be used to provide damping against SSR, and this function has been modelled. Simulation studies have been carried out in PSCAD. In addition, a real-time hardware-in-the-loop HVDC test rig has been used to implement and validate the proposed damping scheme on an experimental platform. When faults occur within AC onshore networks, offshore MTDC networks are vulnerable to DC overvoltages, potentially damaging the DC plant and cables. Power reduction and power dissipation control systems were investigated to ride through onshore AC faults. These methods do not require dedicated fast communication systems. Simulations and laboratory experiments are carried out to evaluate the control systems, with the results from the two platforms compared..

  9. PROJECT HEAVEN: Preoperative Training in Virtual Reality

    PubMed Central

    Iamsakul, Kiratipath; Pavlovcik, Alexander V.; Calderon, Jesus I.; Sanderson, Lance M.

    2017-01-01

    A cephalosomatic anastomosis (CSA; also called HEAVEN: head anastomosis venture) has been proposed as an option for patients with neurological impairments, such as spinal cord injury (SCI), and terminal medical illnesses, for which medicine is currently powerless. Protocols to prepare a patient for life after CSA do not currently exist. However, methods used in conventional neurorehabilitation can be used as a reference for developing preparatory training. Studies on virtual reality (VR) technologies have documented VR's ability to enhance rehabilitation and improve the quality of recovery in patients with neurological disabilities. VR-augmented rehabilitation resulted in increased motivation towards performing functional training and improved the biopsychosocial state of patients. In addition, VR experiences coupled with haptic feedback promote neuroplasticity, resulting in the recovery of motor functions in neurologically-impaired individuals. To prepare the recipient psychologically for life after CSA, the development of VR experiences paired with haptic feedback is proposed. This proposal aims to innovate techniques in conventional neurorehabilitation to implement preoperative psychological training for the recipient of HEAVEN. Recipient's familiarity to body movements will prevent unexpected psychological reactions from occurring after the HEAVEN procedure. PMID:28540125

  10. PROJECT HEAVEN: Preoperative Training in Virtual Reality.

    PubMed

    Iamsakul, Kiratipath; Pavlovcik, Alexander V; Calderon, Jesus I; Sanderson, Lance M

    2017-01-01

    A cephalosomatic anastomosis (CSA; also called HEAVEN: head anastomosis venture) has been proposed as an option for patients with neurological impairments, such as spinal cord injury (SCI), and terminal medical illnesses, for which medicine is currently powerless. Protocols to prepare a patient for life after CSA do not currently exist. However, methods used in conventional neurorehabilitation can be used as a reference for developing preparatory training. Studies on virtual reality (VR) technologies have documented VR's ability to enhance rehabilitation and improve the quality of recovery in patients with neurological disabilities. VR-augmented rehabilitation resulted in increased motivation towards performing functional training and improved the biopsychosocial state of patients. In addition, VR experiences coupled with haptic feedback promote neuroplasticity, resulting in the recovery of motor functions in neurologically-impaired individuals. To prepare the recipient psychologically for life after CSA, the development of VR experiences paired with haptic feedback is proposed. This proposal aims to innovate techniques in conventional neurorehabilitation to implement preoperative psychological training for the recipient of HEAVEN. Recipient's familiarity to body movements will prevent unexpected psychological reactions from occurring after the HEAVEN procedure.

  11. Advanced Protection & Service Restoration for FREEDM Systems

    NASA Astrophysics Data System (ADS)

    Singh, Urvir

    A smart electric power distribution system (FREEDM system) that incorporates DERs (Distributed Energy Resources), SSTs (Solid State Transformers - that can limit the fault current to two times of the rated current) & RSC (Reliable & Secure Communication) capabilities has been studied in this work in order to develop its appropriate protection & service restoration techniques. First, a solution is proposed that can make conventional protective devices be able to provide effective protection for FREEDM systems. Results show that although this scheme can provide required protection but it can be quite slow. Using the FREEDM system's communication capabilities, a communication assisted Overcurrent (O/C) protection scheme is proposed & results show that by using communication (blocking signals) very fast operating times are achieved thereby, mitigating the problem of conventional O/C scheme. Using the FREEDM System's DGI (Distributed Grid Intelligence) capability, an automated FLISR (Fault Location, Isolation & Service Restoration) scheme is proposed that is based on the concept of 'software agents' & uses lesser data (than conventional centralized approaches). Test results illustrated that this scheme is able to provide a global optimal system reconfiguration for service restoration.

  12. Parametric Weight Comparison of Current and Proposed Thermal Protection System (TPS) Concepts

    NASA Technical Reports Server (NTRS)

    Myers, David E.; Martin, Carl J.; Blosser, Max L.

    1999-01-01

    A parametric weight assessment of advanced metallic panel, ceramic blanket, and ceramic tile thermal protection systems (TPS) was conducted using an implicit, one-dimensional (1 -D) thermal finite element sizing code. This sizing code contained models to ac- count for coatings, fasteners, adhesives, and strain isolation pads. Atmospheric entry heating profiles for two vehicles, the Access to Space (ATS) rocket-powered single-stage-to-orbit (SSTO) vehicle and a proposed Reusable Launch Vehicle (RLV), were used to ensure that the trends were not unique to a particular trajectory. Eight TPS concepts were compared for a range of applied heat loads and substructural heat capacities to identify general trends. This study found the blanket TPS concepts have the lightest weights over the majority of their applicable ranges, and current technology ceramic tiles and metallic TPS concepts have similar weights. A proposed, state-of-the-art metallic system which uses a higher temperature alloy and efficient multilayer insulation was predicted to be significantly lighter than the ceramic tile systems and approaches blanket TPS weights for higher integrated heat loads.

  13. Superconducting dc Current Limiting Vacuum Circuit Breaker

    NASA Astrophysics Data System (ADS)

    Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Bunin, R. A.; Voloshin, I. F.; Degtyarenko, P. N.; Yevsin, D. V.; Ivanov, V. P.; Sidorov, V. A.; Fisher, L. M.; Tshai, E. V.

    Acircuitofadc superconductingfault current limiter witha direct current circuit-breaker fora nominal current 300A is proposed. It includes the 2G high temperature superconducting (HTS) tapes and the high-speed dc vacuum circuit breaker.Thetestresultsof current-limitingcapacityandrecoverytimeof superconductivityafter currentfaultatvoltage upto3 kV are presented.

  14. Small business innovation research program solicitation: Closing date July 16, 1990

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This is the eighth annual solicitation by NASA addressed to small business firms, inviting them to submit proposals for research, or research and development, activities in some of the science and engineering areas of interest to NASA. The solicitation describes the Small Business Innovative Research (SBIR) program, identifies eligibility requirements, outlines the required proposal format and content, states proposal preparation and submission requirements, describes the proposal evaluation and award selection process, and provides other information to assist those interested in participating in NASA's SBIR program. It also identifies the technical topics and subtopics for which SBIR proposals are solicited. These cover a broad range of current NASA interests, but do not necessarily include all areas in which NASA plans or currently conducts research. High-risk high pay-off innovations are desired.

  15. Testing a social-cognitive model of moral behavior: the interactive influence of situations and moral identity centrality.

    PubMed

    Aquino, Karl; Freeman, Dan; Reed, Americus; Felps, Will; Lim, Vivien K G

    2009-07-01

    This article proposes and tests a social-cognitive framework for examining the joint influence of situational factors and the centrality of moral identity on moral intentions and behaviors. The authors hypothesized that if a situational factor increases the current accessibility of moral identity within the working self-concept, then it strengthens the motivation to act morally. In contrast, if a situational factor decreases the current accessibility of moral identity, then it weakens the motivation to act morally. The authors also expected the influence of situational factors to vary depending on the extent to which moral identity was central to a person's overall self-conception. Hypotheses derived from the framework were tested in 4 studies. The studies used recalling and reading a list of the Ten Commandments (Study 1), writing a story using morally laden terms (Study 4), and the presence of performance-based financial incentives (Studies 2 and 3) as situational factors. Participants' willingness to initiate a cause-related marketing program (Study 1), lie to a job candidate during a salary negotiation (Studies 2 and 3), and contribute to a public good (Study 4) were examined. Results provide strong support for the proposed framework. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  16. Comparison of DSM-IV and proposed ICD-11 formulations of PTSD among civilian survivors of war and war veterans.

    PubMed

    Morina, Nexhmedin; van Emmerik, Arnold A P; Andrews, Bernice; Brewin, Chris R

    2014-12-01

    The World Health Organization recently proposed a reformulation of posttraumatic stress disorder (PTSD) for the 11(th) edition of the International Classification of Diseases (ICD-11), employing only 6 symptoms. The aim of this study was to investigate the impact of this reformulation of PTSD as compared to criteria according to Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV; American Psychiatric Association, 1994) on the prevalence of current PTSD as well as comorbid major depressive episode and anxiety disorders other than PTSD. Study 1 involved previously collected interviews with 560 Kosovar civilian war survivors; Study 2 employed a previously collected sample of 142 British war veterans. Results revealed no change in the diagnostic status under the criteria proposed for ICD-11 in 87.5% of civilian war survivors and 91.5% of war veterans. Participants who only met the newly proposed criteria showed lower rates of comorbid major depressive episode than participants who only met DSM-IV criteria (13.6% vs. 43.8% respectively). Rates of comorbid anxiety disorders did not significantly differ between participants who lost or gained a PTSD diagnosis under the proposed criteria. Copyright © 2014 International Society for Traumatic Stress Studies.

  17. Current Therapy of Acquired Ocular Toxoplasmosis: A Review.

    PubMed

    Lima, Guilherme Sturzeneker Cerqueira; Saraiva, Patricia Grativol Costa; Saraiva, Fábio Petersen

    2015-11-01

    Caused by the parasite Toxoplasma gondii, ocular toxoplasmosis (OT) is the most common form of posterior infectious uveitis. Combined antiparasitic therapy is the standard treatment for OT, but several other schemes have been proposed. The purpose of the present study was to review the literature on the treatment of OT and provide ophthalmologists with up-to-date information to help reduce OT-related visual morbidity. In conclusion, no ideal treatment scheme was identified; currently prescribed therapeutic schemes yield statistically similar functional outcomes.

  18. Automatic tracking of labeled red blood cells in microchannels.

    PubMed

    Pinho, Diana; Lima, Rui; Pereira, Ana I; Gayubo, Fernando

    2013-09-01

    The current study proposes an automatic method for the segmentation and tracking of red blood cells flowing through a 100- μm glass capillary. The original images were obtained by means of a confocal system and then processed in MATLAB using the Image Processing Toolbox. The measurements obtained with the proposed automatic method were compared with the results determined by a manual tracking method. The comparison was performed by using both linear regressions and Bland-Altman analysis. The results have shown a good agreement between the two methods. Therefore, the proposed automatic method is a powerful way to provide rapid and accurate measurements for in vitro blood experiments in microchannels. Copyright © 2012 John Wiley & Sons, Ltd.

  19. SLAE–CPS: Smart Lean Automation Engine Enabled by Cyber-Physical Systems Technologies

    PubMed Central

    Ma, Jing; Wang, Qiang; Zhao, Zhibiao

    2017-01-01

    In the context of Industry 4.0, the demand for the mass production of highly customized products will lead to complex products and an increasing demand for production system flexibility. Simply implementing lean production-based human-centered production or high automation to improve system flexibility is insufficient. Currently, lean automation (Jidoka) that utilizes cyber-physical systems (CPS) is considered a cost-efficient and effective approach for improving system flexibility under shrinking global economic conditions. Therefore, a smart lean automation engine enabled by CPS technologies (SLAE–CPS), which is based on an analysis of Jidoka functions and the smart capacity of CPS technologies, is proposed in this study to provide an integrated and standardized approach to design and implement a CPS-based smart Jidoka system. A set of comprehensive architecture and standardized key technologies should be presented to achieve the above-mentioned goal. Therefore, a distributed architecture that joins service-oriented architecture, agent, function block (FB), cloud, and Internet of things is proposed to support the flexible configuration, deployment, and performance of SLAE–CPS. Then, several standardized key techniques are proposed under this architecture. The first one is for converting heterogeneous physical data into uniform services for subsequent abnormality analysis and detection. The second one is a set of Jidoka scene rules, which is abstracted based on the analysis of the operator, machine, material, quality, and other factors in different time dimensions. These Jidoka rules can support executive FBs in performing different Jidoka functions. Finally, supported by the integrated and standardized approach of our proposed engine, a case study is conducted to verify the current research results. The proposed SLAE–CPS can serve as an important reference value for combining the benefits of innovative technology and proper methodology. PMID:28657577

  20. SLAE-CPS: Smart Lean Automation Engine Enabled by Cyber-Physical Systems Technologies.

    PubMed

    Ma, Jing; Wang, Qiang; Zhao, Zhibiao

    2017-06-28

    In the context of Industry 4.0, the demand for the mass production of highly customized products will lead to complex products and an increasing demand for production system flexibility. Simply implementing lean production-based human-centered production or high automation to improve system flexibility is insufficient. Currently, lean automation (Jidoka) that utilizes cyber-physical systems (CPS) is considered a cost-efficient and effective approach for improving system flexibility under shrinking global economic conditions. Therefore, a smart lean automation engine enabled by CPS technologies (SLAE-CPS), which is based on an analysis of Jidoka functions and the smart capacity of CPS technologies, is proposed in this study to provide an integrated and standardized approach to design and implement a CPS-based smart Jidoka system. A set of comprehensive architecture and standardized key technologies should be presented to achieve the above-mentioned goal. Therefore, a distributed architecture that joins service-oriented architecture, agent, function block (FB), cloud, and Internet of things is proposed to support the flexible configuration, deployment, and performance of SLAE-CPS. Then, several standardized key techniques are proposed under this architecture. The first one is for converting heterogeneous physical data into uniform services for subsequent abnormality analysis and detection. The second one is a set of Jidoka scene rules, which is abstracted based on the analysis of the operator, machine, material, quality, and other factors in different time dimensions. These Jidoka rules can support executive FBs in performing different Jidoka functions. Finally, supported by the integrated and standardized approach of our proposed engine, a case study is conducted to verify the current research results. The proposed SLAE-CPS can serve as an important reference value for combining the benefits of innovative technology and proper methodology.

  1. A framework for evaluating proposals for scientific activities in wilderness

    Treesearch

    Peter Landres

    2000-01-01

    This paper presents a structured framework for evaluating proposals for scientific activities in wilderness. Wilderness managers receive proposals for scientific activities ranging from unobtrusive inventorying of plants and animals to the use of chainsaws and helicopters for collecting information. Currently, there is no consistent process for evaluating proposals,...

  2. 7 CFR 3406.20 - Evaluation criteria for research proposals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... current faculty in the natural or social sciences; provide a better research environment, state-of-the-art... 7 Agriculture 15 2011-01-01 2011-01-01 false Evaluation criteria for research proposals. 3406.20... Research Proposal § 3406.20 Evaluation criteria for research proposals. The maximum score a research...

  3. A CMOS power-efficient low-noise current-mode front-end amplifier for neural signal recording.

    PubMed

    Wu, Chung-Yu; Chen, Wei-Ming; Kuo, Liang-Ting

    2013-04-01

    In this paper, a new current-mode front-end amplifier (CMFEA) for neural signal recording systems is proposed. In the proposed CMFEA, a current-mode preamplifier with an active feedback loop operated at very low frequency is designed as the first gain stage to bypass any dc offset current generated by the electrode-tissue interface and to achieve a low high-pass cutoff frequency below 0.5 Hz. No reset signal or ultra-large pseudo resistor is required. The current-mode preamplifier has low dc operation current to enhance low-noise performance and decrease power consumption. A programmable current gain stage is adopted to provide adjustable gain for adaptive signal scaling. A following current-mode filter is designed to adjust the low-pass cutoff frequency for different neural signals. The proposed CMFEA is designed and fabricated in 0.18-μm CMOS technology and the area of the core circuit is 0.076 mm(2). The measured high-pass cutoff frequency is as low as 0.3 Hz and the low-pass cutoff frequency is adjustable from 1 kHz to 10 kHz. The measured maximum current gain is 55.9 dB. The measured input-referred current noise density is 153 fA /√Hz , and the power consumption is 13 μW at 1-V power supply. The fabricated CMFEA has been successfully applied to the animal test for recording the seizure ECoG of Long-Evan rats.

  4. Relationships among Emotional and Intellectual Overexcitability, Emotional IQ, and Subjective Well-Being

    ERIC Educational Resources Information Center

    Beduna, Kerry; Perrone-McGovern, Kristin M.

    2016-01-01

    This study focuses on intellectual and emotional overexcitabilities and their relationship to emotional intelligence and subjective well-being. Dabrowski's (1964) theory of positive disintegration (TPD), which proposes that optimum personality development involves the breaking down of current psychological structures, in which individuals…

  5. 75 FR 9901 - Proposed Data Collections Submitted for Public Comment and Recommendations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ...). Background and Brief Description Cigarettes are currently ranked as full-flavor, light or ultralight on the... smokers of cigarettes of different machine-smoked yield categories. Comparison of cigarette smoke... cigarette yield category, biomarkers of exposure, and measures of cardiovascular reactivity. The study has...

  6. Aging Students: Implications for Intergenerational Development in the Classroom.

    ERIC Educational Resources Information Center

    Youngman, Deborah

    1995-01-01

    Outlines current knowledge about integrating older students into the postsecondary educational system, discusses a case study of an established natural learning environment, and presents models of education and development involving older students. A system involving the transposition of dialectical and discourse methods is proposed for moving…

  7. Language Teacher Educators' Pedagogical Knowledge: Validating a Proposed Model

    ERIC Educational Resources Information Center

    Moradkhani, Shahab

    2017-01-01

    The aim of the current study was twofold: identifying the constituent components of language teacher educators' pedagogical knowledge, and investigating possible differences among teachers, teacher educators, and university professors' opinions about these components. Data were collected from 436 participants using a questionnaire. The results of…

  8. Provisional Assessment of Recent Studies on Particulate Matter (2006)

    EPA Science Inventory

    A review of the national ambient air quality standards (NAAQS) for particulate matter (PM) is currently underway. The Criteria Document was completed in October 2004, and a proposed decision to revise the PM NAAQS was published in January 2006. The final decision is to be signe...

  9. Domain-Specific Impulsivity in School-Age Children

    ERIC Educational Resources Information Center

    Tsukayama, Eli; Duckworth, Angela Lee; Kim, Betty

    2013-01-01

    Impulsivity is a salient individual difference in children with well-established predictive validity for life outcomes. The current investigation proposes that impulsive behaviors vary systematically by domain. In a series of studies with ethnically and socioeconomically diverse samples of middle school students, we find that schoolwork-related…

  10. Supervision for School Psychologists in Training: Developing a Framework from Empirical Findings

    ERIC Educational Resources Information Center

    Gibbs, Simon; Atkinson, Cathy; Woods, Kevin; Bond, Caroline; Hill, Vivian; Howe, Julia; Morris, Sue

    2016-01-01

    Similar to other professional disciplines, the importance of supervision within school psychology has attracted considerable attention within recent years. Despite this, systematic review of current literature reveals a dearth of empirical literature proposing underlying theoretical structures. This study extends recent qualitative research by…

  11. A multivariate distance-based analytic framework for microbial interdependence association test in longitudinal study.

    PubMed

    Zhang, Yilong; Han, Sung Won; Cox, Laura M; Li, Huilin

    2017-12-01

    Human microbiome is the collection of microbes living in and on the various parts of our body. The microbes living on our body in nature do not live alone. They act as integrated microbial community with massive competing and cooperating and contribute to our human health in a very important way. Most current analyses focus on examining microbial differences at a single time point, which do not adequately capture the dynamic nature of the microbiome data. With the advent of high-throughput sequencing and analytical tools, we are able to probe the interdependent relationship among microbial species through longitudinal study. Here, we propose a multivariate distance-based test to evaluate the association between key phenotypic variables and microbial interdependence utilizing the repeatedly measured microbiome data. Extensive simulations were performed to evaluate the validity and efficiency of the proposed method. We also demonstrate the utility of the proposed test using a well-designed longitudinal murine experiment and a longitudinal human study. The proposed methodology has been implemented in the freely distributed open-source R package and Python code. © 2017 WILEY PERIODICALS, INC.

  12. International veterinary epilepsy task force consensus report on epilepsy definition, classification and terminology in companion animals.

    PubMed

    Berendt, Mette; Farquhar, Robyn G; Mandigers, Paul J J; Pakozdy, Akos; Bhatti, Sofie F M; De Risio, Luisa; Fischer, Andrea; Long, Sam; Matiasek, Kaspar; Muñana, Karen; Patterson, Edward E; Penderis, Jacques; Platt, Simon; Podell, Michael; Potschka, Heidrun; Pumarola, Martí Batlle; Rusbridge, Clare; Stein, Veronika M; Tipold, Andrea; Volk, Holger A

    2015-08-28

    Dogs with epilepsy are among the commonest neurological patients in veterinary practice and therefore have historically attracted much attention with regard to definitions, clinical approach and management. A number of classification proposals for canine epilepsy have been published during the years reflecting always in parts the current proposals coming from the human epilepsy organisation the International League Against Epilepsy (ILAE). It has however not been possible to gain agreed consensus, "a common language", for the classification and terminology used between veterinary and human neurologists and neuroscientists, practitioners, neuropharmacologists and neuropathologists. This has led to an unfortunate situation where different veterinary publications and textbook chapters on epilepsy merely reflect individual author preferences with respect to terminology, which can be confusing to the readers and influence the definition and diagnosis of epilepsy in first line practice and research studies.In this document the International Veterinary Epilepsy Task Force (IVETF) discusses current understanding of canine epilepsy and presents our 2015 proposal for terminology and classification of epilepsy and epileptic seizures. We propose a classification system which reflects new thoughts from the human ILAE but also roots in former well accepted terminology. We think that this classification system can be used by all stakeholders.

  13. A flat-panel-shaped hybrid piezo/triboelectric nanogenerator for ambient energy harvesting

    NASA Astrophysics Data System (ADS)

    Hassan, Gul; Khan, Fasihullah; Hassan, Arshad; Ali, Shawkat; Bae, Jinho; Lee, Chong Hyun

    2017-04-01

    Recently, many researchers have been paying attention to nanogenerators (NGs) as energy sources for self-powered mirco-nano systems, and studying how to achieve their higher power generation. Hence, we propose a hybrid-type NG for harvesting both the piezoelectric and triboelectric effect simultaneously. In the proposed hybrid NG, the piezoelectric NG (PNG) and triboelectric NG (TENG) are fabricated using polydimethylsiloxane (PDMS) and perovskite zinc stannite (ZnSnO3) nanocubes with a high charge polarization of 59 uC cm-2 composite (PDMS + ZnSnO3) and UV surface-treated PDMS, respectively. To effectively combine a high output current of PNG and a high voltage of TENG, these two NGs are stacked upon each other, and separated by sponge spacers providing a uniform air gap for the triboelectric effect. In particular, this fabricated structure has a low Young’s modulus for piezoelectricity. The proposed hybrid NG device effectively achieves a combined peak voltage of 300 V on an open circuit, a power density of 10.41 mW cm-2 at 1 MΩ load, and a maximum short circuit current density of 16 mA cm-2 at 50 Ω load. It is feasible that the proposed NG can be utilized as a source for various self-powered systems.

  14. Current superimposition variable flux reluctance motor with 8 salient poles

    NASA Astrophysics Data System (ADS)

    Takahara, Kazuaki; Hirata, Katsuhiro; Niguchi, Noboru; Kohara, Akira

    2017-12-01

    We propose a current superimposition variable flux reluctance motor for a traction motor of electric vehicles and hybrid electric vehicles, which consists of 10 salient poles in the rotor and 12 slots in the stator. However, iron losses of this motor in high rotation speed ranges is large because the number of salient poles is large. In this paper, we propose a current superimposition variable flux reluctance motor that consists of 8 salient poles and 12 slots. The characteristics of the 10-pole-12-slot and 8-pole-12-slot current superimposition variable flux reluctance motors are compared using finite element analysis under vector control.

  15. On-line tool breakage monitoring of vibration tapping using spindle motor current

    NASA Astrophysics Data System (ADS)

    Li, Guangjun; Lu, Huimin; Liu, Gang

    2008-10-01

    Input current of driving motor has been employed successfully as monitoring the cutting state in manufacturing processes for more than a decade. In vibration tapping, however, the method of on-line monitoring motor electric current has not been reported. In this paper, a tap failure prediction method is proposed to monitor the vibration tapping process using the electrical current signal of the spindle motor. The process of vibration tapping is firstly described. Then the relationship between the torque of vibration tapping and the electric current of motor is investigated by theoretic deducing and experimental measurement. According to those results, a monitoring method of tool's breakage is proposed through monitoring the ratio of the current amplitudes during adjacent vibration tapping periods. Finally, a low frequency vibration tapping system with motor current monitoring is built up using a servo motor B-106B and its driver CR06. The proposed method has been demonstrated with experiment data of vibration tapping in titanic alloys. The result of experiments shows that the method, which can avoid the tool breakage and giving a few error alarms when the threshold of amplitude ratio is 1.2 and there is at least 2 times overrun among 50 adjacent periods, is feasible for tool breakage monitoring in the process of vibration tapping small thread holes.

  16. Evaluation of ion collection area in Faraday probes.

    PubMed

    Brown, Daniel L; Gallimore, Alec D

    2010-06-01

    A Faraday probe with three concentric rings was designed and fabricated to assess the effect of gap width and collector diameter in a systematic study of the diagnostic ion collection area. The nested Faraday probe consisted of two concentric collector rings and an outer guard ring, which enabled simultaneous current density measurements on the inner and outer collectors. Two versions of the outer collector were fabricated to create gaps of 0.5 and 1.5 mm between the rings. Distribution of current density in the plume of a low-power Hall thruster ion source was measured in azimuthal sweeps at constant radius from 8 to 20 thruster diameters downstream of the exit plane with variation in facility background pressure. A new analytical technique is proposed to account for ions collected in the gap between the Faraday probe collector and guard ring. This method is shown to exhibit excellent agreement between all nested Faraday probe configurations, and to reduce the magnitude of integrated ion beam current to levels consistent with Hall thruster performance analyses. The technique is further studied by varying the guard ring bias potential with a fixed collector bias potential, thereby controlling ion collection in the gap. Results are in agreement with predictions based on the proposed analytical technique. The method is applied to a past study comparing the measured ion current density profiles of two Faraday probe designs. These findings provide new insight into the nature of ion collection in Faraday probe diagnostics, and lead to improved accuracy with a significant reduction in measurement uncertainty.

  17. High efficiency H6 single-phase transformerless grid-tied PV inverter with proposed modulation for reactive power generation

    NASA Astrophysics Data System (ADS)

    Almasoudi, Fahad M.; Alatawi, Khaled S.; Matin, Mohammad

    2017-08-01

    Implementation of transformerless inverters in PV grid-tied system offer great benefits such as high efficiency, light weight, low cost, etc. Most of the proposed transformerless inverters in literature are verified for only real power application. Currently, international standards such as VDE-AR-N 4105 has demanded that PV grid-tied inverters should have the ability of controlling a specific amount of reactive power. Generation of reactive power cannot be accomplished in single phase transformerless inverter topologies because the existing modulation techniques are not adopted for a freewheeling path in the negative power region. This paper enhances a previous high efficiency proposed H6 trnasformerless inverter with SiC MOSFETs and demonstrates new operating modes for the generation of reactive power. A proposed pulse width modulation (PWM) technique is applied to achieve bidirectional current flow through freewheeling state. A comparison of the proposed H6 transformerless inverter using SiC MOSFETs and Si MOSFTEs is presented in terms of power losses and efficiency. The results show that reactive power control is attained without adding any additional active devices or modification to the inverter structure. Also, the proposed modulation maintains a constant common mode voltage (CM) during every operating mode and has low leakage current. The performance of the proposed system verifies its effectiveness in the next generation PV system.

  18. Survey of Current and Proposed Allied Health Education Programs in New Mexico Post-Secondary Institutions, 1991.

    ERIC Educational Resources Information Center

    McLaughlin, James L.; Burr, Marjorie

    In spring 1991, the Council of Chief Instructional Officers of New Mexico two-year institutions compiled information on current and proposed allied health programs in order to foster cooperation and planning in allied health education among the 17 institutions in the state. In summer 1991, the compilation was updated to include allied health…

  19. Screening for Elevated Blood Lead Levels in Children: Assessment of Criteria and a Proposal for New Ones in France

    PubMed Central

    Etchevers, Anne; Glorennec, Philippe; Le Strat, Yann; Lecoffre, Camille; Bretin, Philippe; Le Tertre, Alain

    2015-01-01

    The decline in children’s Blood Lead Levels (BLL) raises questions about the ability of current lead poisoning screening criteria to identify those children most exposed. The objectives of the study were to evaluate the performance of current screening criteria in identifying children with blood lead levels higher than 50 µg/L in France, and to propose new criteria. Data from a national French survey, conducted among 3831 children aged 6 months to 6 years in 2008–2009 were used. The sensitivity and specificity of the current criteria in predicting blood lead levels higher than or equal to 50 µg/L were evaluated. Two predictive models of BLL above 44 µg/L (for lack of sufficient sample size at 50 µg/L) were built: the first using current criteria, and the second using newly identified risk factors. For each model, performance was studied by calculating the area under the ROC (Receiver Operating Characteristic) curve. The sensitivity of current criteria for detecting BLL higher than or equal to 50 µg/L was 0.51 (0.26; 0.75) and specificity was 0.66 (0.62; 0.70). The new model included the following criteria: foreign child newly arrived in France, mother born abroad, consumption of tap water in the presence of lead pipes, pre-1949 housing, period of construction of housing unknown, presence of peeling paint, parental smoking at home, occupancy rates for housing and child’s address in a cadastral municipality or census block comprising more than 6% of housing that is potentially unfit and built pre-1949. The area under the ROC curve was 0.86 for the new model, versus 0.76 for the current one. The lead poisoning screening criteria should be updated. The risk of industrial, occupational and hobby-related exposure could not be assessed in this study, but should be kept as screening criteria. PMID:26633457

  20. 78 FR 37164 - Revisions to the Air Emissions Reporting Requirements: Revisions to Lead (Pb) Reporting Threshold...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-20

    ...Today's action proposes changes to the existing EPA emission inventory reporting requirements on state, local, and tribal agencies in the current Air Emissions Reporting Requirements rule published on December 17, 2008. The proposed amendments would lower the current threshold for reporting Pb sources as point sources; eliminate the requirement for reporting emissions from wildfires and prescribed fires; and replace a requirement for reporting mobile source emissions with a requirement for reporting the input parameters that can be used to run the EPA models that generate the emissions estimates. In addition, the proposed amendments would reduce the reporting burden on state, local, and tribal agencies by removing the requirements to report daily and seasonal emissions associated with carbon monoxide (CO), ozone (O3), and particulate matter up to 10 micrometers in size (PM10) nonattainment areas and nitrogen oxides (NOX) State Implementation Plan (SIP) call areas, although reporting requirements for those emissions would remain in other regulations. Lastly, the proposed amendments would clarify, remove, or simplify some current emissions reporting requirements which we believe are not necessary or are not clearly aligned with current inventory terminology and practices.

  1. Al embedded MgO barrier MTJ: A first principle study for application in fast and compact STT-MRAMs

    NASA Astrophysics Data System (ADS)

    Yadav, Manoj Kumar; Gupta, Santosh Kumar; Rai, Sanjeev; Pandey, Avinash C.

    2017-03-01

    The first principle comparative study of a novel single Al sheet embedded MgO and pure MgO barrier having Fe electrodes magnetic tunnel junction has been presented. Al embedded MgO is reported to provide enhanced spin polarised tunnelling current due to increase of spin-polarized density of states at Fermi energy in the barrier region. This novel MTJ provides a current density and resistance area (RA) product of 94.497 ×107 A / cm2 and 0.105  Ω - μm2 respectively. With such a low RA product; it allows higher deriving current due to which switching time of magnetization reversal reduces without inducing barrier related breakdowns in non-volatile magnetic random access memories. The low RA product and high current density of the proposed MTJ may have possible applications in integration with existing MOS circuits.

  2. Models for truth-telling in physician-patient encounters: what can we learn from Yoruba concept of Ooto?

    PubMed

    Ewuoso, Cornelius

    2017-09-29

    Empirical studies have now established that many patients make clinical decisions based on models other than Anglo American model of truth-telling and patient autonomy. Some scholars also add that current medical ethics frameworks and recent proposals for enhancing communication in health professional-patient relationship have not adequately accommodated these models. In certain clinical contexts where health professional and patients are motivated by significant cultural and religious values, these current frameworks cannot prevent communication breakdown, which can, in turn, jeopardize patient care, cause undue distress to a patient in certain clinical contexts or negatively impact his/her relationship with the community. These empirical studies have now recommended that additional frameworks developed around other models of truth-telling; and which take very seriously significant value-differences which sometimes exist between health professional and patients, as well as patient's cultural/religious values or relational capacities, must be developed. This paper contributes towards the development of one. Specifically, this study proposes a framework for truth-telling developed around African model of truth-telling by drawing insights from the communitarian concept of ootọ́ amongst the Yoruba people of south west Nigeria. I am optimistic that if this model is incorporated into current medical ethics codes and curricula, it will significantly enhance health professional-patient communication. © 2017 John Wiley & Sons Ltd.

  3. An inductance Fourier decomposition-based current-hysteresis control strategy for switched reluctance motors

    NASA Astrophysics Data System (ADS)

    Hua, Wei; Qi, Ji; Jia, Meng

    2017-05-01

    Switched reluctance machines (SRMs) have attracted extensive attentions due to the inherent advantages, including simple and robust structure, low cost, excellent fault-tolerance and wide speed range, etc. However, one of the bottlenecks limiting the SRMs for further applications is its unfavorable torque ripple, and consequently noise and vibration due to the unique doubly-salient structure and pulse-current-based power supply method. In this paper, an inductance Fourier decomposition-based current-hysteresis-control (IFD-CHC) strategy is proposed to reduce torque ripple of SRMs. After obtaining a nonlinear inductance-current-position model based Fourier decomposition, reference currents can be calculated by reference torque and the derived inductance model. Both the simulations and experimental results confirm the effectiveness of the proposed strategy.

  4. Liver allocation and distribution: time for a change.

    PubMed

    Deshpande, Ranjit; Hirose, Ryutaro; Mulligan, David

    2017-04-01

    Liver allograft allocation has been a topic of hot debate for over a decade. New redistricting changes have been proposed by the Liver and Intestinal Transplant Committee to the existing United Network for Organ Sharing (UNOS) liver allocation policy. The basis of this new proposal is similar to the old one with an aim to distribute organs in a fair, efficient and equitable fashion. In this review, we plan to look in depth at the redistribution proposals thus far, their merits and how they may help patients who do not have adequate access to livers. Many authors have criticized the proposed changes to organ distribution to reduce geographic disparity in access to liver transplantation. Our focus in this article is to bring forth the most recent literature and proposed changes in the current distribution system. We will also mention two other possible methods that have been proposed to redesign distribution using concentric circles and neighborhoods. In this article, we also look at the economics of the redistricting proposal and its effects on transplant centers. The UNOS Liver and Intestinal Transplant Committee has recommended a proposal using the eight-district model with proximity circles and three additional Model for End-Stage Liver Disease (MELD) points with initial sharing MELD threshold of 25 as a starting point to reduce disparity in patient access to deceased donor livers for transplantation. This proposal has met with significant resistance because of concerns of cost, logistics and impact on existing transplant centers. Other methodologies have also been proposed that have the potential to significantly improve our current disparity of access to life-saving organs. Variation in the supply of donor organs vs. the demand or need for liver transplant by geography and the current defined areas of distribution drive this disparity. Cost benefits to the healthcare system in caring for patients with advanced stages of liver disease may outweigh increased costs of transportation and transplantation. The current allocation boundaries are not optimal for liver distribution, as modeled by all suggested solutions thus far. The need to identify a more optimal and equitable allocation/distribution system is paramount.

  5. 24 CFR 941.303 - Site acquisition proposal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... least sixty (60) days after proposal submission. (c) Zoning. Evidence that construction or rehabilitation is permitted by current zoning ordinances or regulations or evidence to indicate that needed... stage. (e) Environmental assessment. All available environmental information on the proposed development...

  6. 24 CFR 941.303 - Site acquisition proposal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... least sixty (60) days after proposal submission. (c) Zoning. Evidence that construction or rehabilitation is permitted by current zoning ordinances or regulations or evidence to indicate that needed... stage. (e) Environmental assessment. All available environmental information on the proposed development...

  7. Computer modeling of inversion layer MOS solar cells and arrays

    NASA Technical Reports Server (NTRS)

    Ho, Fat Duen

    1991-01-01

    A two dimensional numerical model of the inversion layer metal insulator semiconductor (IL/MIS) solar cell is proposed by using the finite element method. The two-dimensional current flow in the device is taken into account in this model. The electrostatic potential distribution, the electron concentration distribution, and the hole concentration distribution for different terminal voltages are simulated. The results of simple calculation are presented. The existing problems for this model are addressed. Future work is proposed. The MIS structures are studied and some of the results are reported.

  8. Theoretical proposal for determining angular momentum compensation in ferrimagnets

    NASA Astrophysics Data System (ADS)

    Zhu, Zhifeng; Fong, Xuanyao; Liang, Gengchiau

    2018-05-01

    This work demonstrates that the magnetization and angular momentum compensation temperatures (TMC and TAMC) in ferrimagnets can be unambiguously determined by performing two sets of temperature-dependent current switching, with the symmetry reversals at TMC and TAMC, respectively. A theoretical model based on the modified Landau-Lifshitz-Bloch equation is developed to systematically study the spin torque effect under different temperatures, and numerical simulations are performed to corroborate our proposal. Furthermore, we demonstrate that the recently reported linear relation between TAMC and TMC can be explained using the Curie-Weiss theory.

  9. Future long-baseline neutrino oscillations: View from Asia

    NASA Astrophysics Data System (ADS)

    Hayato, Yoshinari

    2015-07-01

    Accelerator based long-baseline neutrino oscillation experiments have been playing important roles in revealing the nature of neutrinos. However, it turned out that the current experiments are not sufficient to study two major remaining problems, the CP violation in the lepton sector and the mass hierarchy of neutrinos. Therefore, several new experiments have been proposed. Among of them, two accelerator based long-baseline neutrino oscillation experiments, the J-PARC neutrino beam and Hyper-Kamiokande, and MOMENT, have been proposed in Asia. These two projects are reviewed in this article.

  10. Incipient fault detection and power system protection for spaceborne systems

    NASA Technical Reports Server (NTRS)

    Russell, B. Don; Hackler, Irene M.

    1987-01-01

    A program was initiated to study the feasibility of using advanced terrestrial power system protection techniques for spacecraft power systems. It was designed to enhance and automate spacecraft power distribution systems in the areas of safety, reliability and maintenance. The proposed power management/distribution system is described as well as security assessment and control, incipient and low current fault detection, and the proposed spaceborne protection system. It is noted that the intelligent remote power controller permits the implementation of digital relaying algorithms with both adaptive and programmable characteristics.

  11. High-level specification of a proposed information architecture for support of a bioterrorism early-warning system.

    PubMed

    Berkowitz, Murray R

    2013-01-01

    Current information systems for use in detecting bioterrorist attacks lack a consistent, overarching information architecture. An overview of the use of biological agents as weapons during a bioterrorist attack is presented. Proposed are the design, development, and implementation of a medical informatics system to mine pertinent databases, retrieve relevant data, invoke appropriate biostatistical and epidemiological software packages, and automatically analyze these data. The top-level information architecture is presented. Systems requirements and functional specifications for this level are presented. Finally, future studies are identified.

  12. Segmentation of Object Outlines into Parts: A Large-Scale Integrative Study

    ERIC Educational Resources Information Center

    De Winter, Joeri; Wagemans, Johan

    2006-01-01

    In this study, a large number of observers (N=201) were asked to segment a collection of outlines derived from line drawings of everyday objects (N=88). This data set was then used as a benchmark to evaluate current models of object segmentation. All of the previously proposed rules of segmentation were found supported in our results. For example,…

  13. Teachers' Attitude towards ICT Use in Secondary Schools: A Scale Development Study

    ERIC Educational Resources Information Center

    Aydin, Mehmet Kemal; Semerci, Ali; Gürol, Mehmet

    2016-01-01

    The current study aims to develop a valid and reliable instrument that measures secondary school teachers' attitudes towards ICT use in teaching and learning process. A cross-sectional survey design was employed with a group of 173 teachers. Based on the literature review, a pool of 21 items was proposed and reviewed by a board of experts. As to…

  14. "The Project Cannot Be Approved in Its Current Form": Feminist Visual Research Meets the Human Research Ethics Committee

    ERIC Educational Resources Information Center

    Pitt, Penelope

    2014-01-01

    This article reflects on a university human research ethics committee's unease regarding a feminist visual pilot study within the field of education. The small exploratory study proposed to explore a migrant mother's production of her son's identity through her family photograph collection. The committee requested substantial…

  15. Risky Lifestyle as a Mediator of the Relationship between Deviant Peer Affiliation and Dating Violence Victimization among Adolescent Girls

    ERIC Educational Resources Information Center

    Vezina, Johanne; Hebert, Martine; Poulin, Francois; Lavoie, Francine; Vitaro, Frank; Tremblay, Richard E.

    2011-01-01

    Few studies have explored the possible contribution of the peer group to dating violence victimization. The current study tested the hypothesis that a risky lifestyle would mediate the relationship between deviant peer affiliation and dating violence victimization among adolescent girls. The proposed mediation model was derived from lifestyles and…

  16. Growth Patterns and E-Moderating Supports in Asynchronous Online Discussions in an Undergraduate Blended Course

    ERIC Educational Resources Information Center

    Ghadirian, Hajar; Ayub, Ahmad Fauzi Mohd; Bakar, Kamariah Binti Abu; Hassanzadeh, Maryam

    2016-01-01

    This study presents a case study of asynchronous online discussions' (AOD) growth patterns in an undergraduate blended course to address the gap in our current understanding of how threads are developed in peer-moderated AODs. Building on a taxonomy of thread pattern proposed by Chan, Hew and Cheung (2009), growth patterns of thirty-six forums…

  17. Intervention studies to foster resilience - A systematic review and proposal for a resilience framework in future intervention studies.

    PubMed

    Chmitorz, A; Kunzler, A; Helmreich, I; Tüscher, O; Kalisch, R; Kubiak, T; Wessa, M; Lieb, K

    2018-02-01

    Psychological resilience refers to the phenomenon that many people are able to adapt to the challenges of life and maintain mental health despite exposure to adversity. This has stimulated research on training programs to foster psychological resilience. We evaluated concepts, methods and designs of 43 randomized controlled trials published between 1979 and 2014 which assessed the efficacy of such training programs and propose standards for future intervention research based on recent developments in the field. We found that concepts, methods and designs in current resilience intervention studies are of limited use to properly assess efficacy of interventions to foster resilience. Major problems are the use of definitions of resilience as trait or a composite of resilience factors, the use of unsuited assessment instruments, and inappropriate study designs. To overcome these challenges, we propose 1) an outcome-oriented definition of resilience, 2) an outcome-oriented assessment of resilience as change in mental health in relation to stressor load, and 3) methodological standards for suitable study designs of future intervention studies. Our proposals may contribute to an improved quality of resilience intervention studies and may stimulate further progress in this growing research field. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Disturbed flow mediated modulation of shear forces on endothelial plane: A proposed model for studying endothelium around atherosclerotic plaques

    NASA Astrophysics Data System (ADS)

    Balaguru, Uma Maheswari; Sundaresan, Lakshmikirupa; Manivannan, Jeganathan; Majunathan, Reji; Mani, Krishnapriya; Swaminathan, Akila; Venkatesan, Saravanakumar; Kasiviswanathan, Dharanibalan; Chatterjee, Suvro

    2016-06-01

    Disturbed fluid flow or modulated shear stress is associated with vascular conditions such as atherosclerosis, thrombosis, and aneurysm. In vitro simulation of the fluid flow around the plaque micro-environment remains a challenging approach. Currently available models have limitations such as complications in protocols, high cost, incompetence of co-culture and not being suitable for massive expression studies. Hence, the present study aimed to develop a simple, versatile model based on Computational Fluid Dynamics (CFD) simulation. Current observations of CFD have shown the regions of modulated shear stress by the disturbed fluid flow. To execute and validate the model in real sense, cell morphology, cytoskeletal arrangement, cell death, reactive oxygen species (ROS) profile, nitric oxide production and disturbed flow markers under the above condition were assessed. Endothelium at disturbed flow region which had been exposed to low shear stress and swirling flow pattern showed morphological and expression similarities with the pathological disturbed flow environment reported previously. Altogether, the proposed model can serve as a platform to simulate the real time micro-environment of disturbed flow associated with eccentric plaque shapes and the possibilities of studying its downstream events.

  19. Heat treatment effects in Cu2S-CdS heterojunction photovoltaic cells

    NASA Technical Reports Server (NTRS)

    Fahrenbruch, A. L.; Bube, R. H.

    1974-01-01

    The dependence of the short-circuit current on photon energy, temperature, and the state of optical degradation (or enhancement) is determined in a study of the photovoltaic properties of Cu2S-CdS single-crystal heterojunctions. A coherent formulation is proposed for the relationship between enhancement and optical degradation and for their effects on the transport of a short-circuit photoexcited current and dark forward-bias current in a photovoltaic cell. Optical degradation in a Cu2S-CdS cell is shown to be identical to the optical degradation of lifetime in a homogeneous CdS:Cd:Cu crystal.

  20. Efficient spin-current injection in single-molecule magnet junctions

    NASA Astrophysics Data System (ADS)

    Xie, Haiqing; Xu, Fuming; Jiao, Hujun; Wang, Qiang; Liang, J.-Q.

    2018-01-01

    We study theoretically spin transport through a single-molecule magnet (SMM) in the sequential and cotunneling regimes, where the SMM is weakly coupled to one ferromagnetic and one normal-metallic leads. By a master-equation approach, it is found that the spin polarization injected from the ferromagnetic lead is amplified and highly polarized spin-current can be generated, due to the exchange coupling between the transport electron and the anisotropic spin of the SMM. Moreover, the spin-current polarization can be tuned by the gate or bias voltage, and thus an efficient spin injection device based on the SMM is proposed in molecular spintronics.

  1. Mesenchymal stem cell therapy in cats: Current knowledge and future potential.

    PubMed

    Quimby, Jessica M; Borjesson, Dori L

    2018-03-01

    Practical relevance: Stem cell therapy is an innovative field of scientific investigation with tremendous potential for clinical application in veterinary medicine. Based on the known desirable immunomodulatory properties of mesenchymal stem cells, this therapy holds promise for the treatment of a variety of inflammatory diseases in cats. This review details our current understanding of feline stem cell biology and proposed mechanism of action. Studies performed in feline clinical trials for diseases including gingivostomatitis, chronic enteropathy, asthma and kidney disease are summarized, with the goal of providing an overview of the current status of this treatment modality and its potential for the future.

  2. Equivalence testing using existing reference data: An example with genetically modified and conventional crops in animal feeding studies.

    PubMed

    van der Voet, Hilko; Goedhart, Paul W; Schmidt, Kerstin

    2017-11-01

    An equivalence testing method is described to assess the safety of regulated products using relevant data obtained in historical studies with assumedly safe reference products. The method is illustrated using data from a series of animal feeding studies with genetically modified and reference maize varieties. Several criteria for quantifying equivalence are discussed, and study-corrected distribution-wise equivalence is selected as being appropriate for the example case study. An equivalence test is proposed based on a high probability of declaring equivalence in a simplified situation, where there is no between-group variation, where the historical and current studies have the same residual variance, and where the current study is assumed to have a sample size as set by a regulator. The method makes use of generalized fiducial inference methods to integrate uncertainties from both the historical and the current data. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Fast and efficient STT switching in MTJ using additional transient pulse current

    NASA Astrophysics Data System (ADS)

    Pathak, Sachin; Cha, Jongin; Jo, Kangwook; Yoon, Hongil; Hong, Jongill

    2017-06-01

    We propose a profile of write pulse current-density to switch magnetization in a perpendicular magnetic tunnel junction to reduce switching time and write energy as well. Our simulated results show that an overshoot transient pulse current-density (current spike) imposed to conventional rectangular-shaped pulse current-density (main pulse) significantly improves switching speed that yields the reduction in write energy accordingly. For example, we could dramatically reduce the switching time by 80% and thereby reduce the write energy over 9% in comparison to the switching without current spike. The current spike affects the spin dynamics of the free layer and reduces the switching time mainly due to spin torque induced. On the other hand, the large Oersted field induced causes changes in spin texture. We believe our proposed write scheme can make a breakthrough in magnetic random access memory technology seeking both high speed operation and low energy consumption.

  4. Current-based detection of nonlocal spin transport in graphene for spin-based logic applications

    NASA Astrophysics Data System (ADS)

    Wen, Hua; Zhu, Tiancong; Luo, Yunqiu Kelly; Amamou, Walid; Kawakami, Roland K.

    2014-05-01

    Graphene has been proposed for novel spintronic devices due to its robust and efficient spin transport properties at room temperature. Some of the most promising proposals require current-based readout for integration purposes, but the current-based detection of spin accumulation has not yet been developed. In this work, we demonstrate current-based detection of spin transport in graphene using a modified nonlocal geometry. By adding a variable shunt resistor in parallel to the nonlocal voltmeter, we are able to systematically cross over from the conventional voltage-based detection to current-based detection. As the shunt resistor is reduced, the output current from the spin accumulation increases as the shunt resistance drops below a characteristic value R*. We analyze this behavior using a one-dimensional drift-diffusion model, which accounts well for the observed behavior. These results provide the experimental and theoretical foundation for current-based detection of nonlocal spin transport.

  5. Junction barrier Schottky rectifier with an improved P-well region

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Li, Ting; Cao, Fei; Shao, Lei; Chen, Yu-Xian

    2012-12-01

    A junction barrier Schottky (JBS) rectifier with an improved P-well on 4H—SiC is proposed to improve the VF—IR trade-off and the breakdown voltage. The reverse current density of the proposed JBS rectifier at 300 K and 800 V is about 3.3×10-8 times that of the common JBS rectifier at no expense of the forward voltage drop. This is because the depletion layer thickness in the P-well region at the same reverse voltage is larger than in the P+ grid, resulting in a lower spreading current and tunneling current. As a result, the breakdown voltage of the proposed JBS rectifier is over 1.6 kV, that is about 0.8 times more than that of the common JBS rectifier due to the uniform electric field. Although the series resistance of the proposed JBS rectifier is a little larger than that of the common JBS rectifier, the figure of merit (FOM) of the proposed JBS rectifier is about 2.9 times that of the common JBS rectifier. Based on simulating the values of susceptibility of the two JBS rectifiers to electrostatic discharge (ESD) in the human body model (HBM) circuits, the failure energy of the proposed JBS rectifier increases 17% compared with that of the common JBS rectifier.

  6. Reusable Rocket Engine Advanced Health Management System. Architecture and Technology Evaluation: Summary

    NASA Technical Reports Server (NTRS)

    Pettit, C. D.; Barkhoudarian, S.; Daumann, A. G., Jr.; Provan, G. M.; ElFattah, Y. M.; Glover, D. E.

    1999-01-01

    In this study, we proposed an Advanced Health Management System (AHMS) functional architecture and conducted a technology assessment for liquid propellant rocket engine lifecycle health management. The purpose of the AHMS is to improve reusable rocket engine safety and to reduce between-flight maintenance. During the study, past and current reusable rocket engine health management-related projects were reviewed, data structures and health management processes of current rocket engine programs were assessed, and in-depth interviews with rocket engine lifecycle and system experts were conducted. A generic AHMS functional architecture, with primary focus on real-time health monitoring, was developed. Fourteen categories of technology tasks and development needs for implementation of the AHMS were identified, based on the functional architecture and our assessment of current rocket engine programs. Five key technology areas were recommended for immediate development, which (1) would provide immediate benefits to current engine programs, and (2) could be implemented with minimal impact on the current Space Shuttle Main Engine (SSME) and Reusable Launch Vehicle (RLV) engine controllers.

  7. Controlling Hysteresis in Superconducting Weak Links and μ-Superconducting Quantum Interference Devices

    NASA Astrophysics Data System (ADS)

    Kumar, Nikhil; Winkelmann, C. B.; Biswas, Sourav; Courtois, H.; Gupta, Anjan K.

    We have fabricated and studied the current-voltage characteristics of a number of niobium film based weak-link devices and μ-SQUIDs showing a critical current and two re-trapping currents. We have proposed a new understanding for the re-trapping currents in terms of thermal instabilities in different portions of the device. We also find that the superconducting proximity effect and the phase-slip processes play an important role in dictating the temperature dependence of the critical current in the non-hysteretic regime. The proximity effect helps in widening the temperature range of hysteresis-free characteristics. Finally we demonstrate control on temperature-range with hysteresis-free characteristics in two ways: 1) By using a parallel shunt resistor in close vicinity of the device, and 2) by reducing the weak-link width. Thus we get non-hysteretic behavior down to 1.3 K temperature in some of the studied devices. We acknowledge the financial support from CSIR, India as well as CNRS-Institute Neel, Grenoble, France.

  8. Design of permanent magnet eddy current brake for a small scaled electromagnetic launch model

    NASA Astrophysics Data System (ADS)

    Zhou, Shigui; Yu, Haitao; Hu, Minqiang; Huang, Lei

    2012-04-01

    A variable pole-pitch double-sided permanent magnet (PM) linear eddy current brake (LECB) is proposed for a small scaled electromagnetic launch model. A two-dimensional (2D) analytical steady state model is presented for the double-sided PM-LECB, and the expression for the braking force is derived. Based on the analytical model, the material and eddy current skin effect of the conducting plate are analyzed. Moreover, a variable pole-pitch double-sided PM-LECB is proposed for the effective braking of the moving plate. In addition, the braking force is predicted by finite element (FE) analysis, and the simulated results are in good agreement with the analytical model. Finally, a prototype is presented to test the braking profile for validation of the proposed design.

  9. Low-Power Photoplethysmogram Acquisition Integrated Circuit with Robust Light Interference Compensation.

    PubMed

    Kim, Jongpal; Kim, Jihoon; Ko, Hyoungho

    2015-12-31

    To overcome light interference, including a large DC offset and ambient light variation, a robust photoplethysmogram (PPG) readout chip is fabricated using a 0.13-μm complementary metal-oxide-semiconductor (CMOS) process. Against the large DC offset, a saturation detection and current feedback circuit is proposed to compensate for an offset current of up to 30 μA. For robustness against optical path variation, an automatic emitted light compensation method is adopted. To prevent ambient light interference, an alternating sampling and charge redistribution technique is also proposed. In the proposed technique, no additional power is consumed, and only three differential switches and one capacitor are required. The PPG readout channel consumes 26.4 μW and has an input referred current noise of 260 pArms.

  10. Low-Power Photoplethysmogram Acquisition Integrated Circuit with Robust Light Interference Compensation

    PubMed Central

    Kim, Jongpal; Kim, Jihoon; Ko, Hyoungho

    2015-01-01

    To overcome light interference, including a large DC offset and ambient light variation, a robust photoplethysmogram (PPG) readout chip is fabricated using a 0.13-μm complementary metal–oxide–semiconductor (CMOS) process. Against the large DC offset, a saturation detection and current feedback circuit is proposed to compensate for an offset current of up to 30 μA. For robustness against optical path variation, an automatic emitted light compensation method is adopted. To prevent ambient light interference, an alternating sampling and charge redistribution technique is also proposed. In the proposed technique, no additional power is consumed, and only three differential switches and one capacitor are required. The PPG readout channel consumes 26.4 μW and has an input referred current noise of 260 pArms. PMID:26729122

  11. A compact rail-to-rail CMOS buffer amplifier with very low quiescent current

    NASA Astrophysics Data System (ADS)

    Arslan, Emre; Yıldız, Merih; Minaei, Shahram

    2015-06-01

    In this work, a very compact, rail-to-rail, high-speed buffer amplifier for liquid crystal display (LCD) applications is proposed. Compared to other buffer amplifiers, the proposed circuit has a very simple architecture, occupies a small number of transistors and also has a large driving capacity with very low quiescent current. It is composed of two complementary differential input stages to provide rail-to-rail driving capacity. The push-pull transistors are directly connected to the differential input stage, and the output is taken from an inverter. The proposed buffer circuit is laid out using Mentor Graphics IC Station layout editor using AMS 0.35 μm process parameters. It is shown by post-layout simulations that the proposed buffer can drive a 1 nF capacitive load within a small settling time under a full voltage swing, while drawing only 1.6 μA quiescent current from a 3.3 V power supply.

  12. Minimization of Ohmic losses for domain wall motion in ferromagnetic nanowires

    NASA Astrophysics Data System (ADS)

    Abanov, Artem; Tretiakov, Oleg; Liu, Yang

    2011-03-01

    We study current-induced domain-wall motion in a narrow ferromagnetic wire. We propose a way to move domain walls with a resonant time-dependent current which dramatically decreases the Ohmic losses in the wire and allows driving of the domain wall with higher speed without burning the wire. For any domain wall velocity we find the time-dependence of the current needed to minimize the Ohmic losses. Below a critical domain-wall velocity specified by the parameters of the wire the minimal Ohmic losses are achieved by dc current. Furthermore, we identify the wire parameters for which the losses reduction from its dc value is the most dramatic. This work was supported by the NSF Grant No. 0757992 and Welch Foundation (A-1678).

  13. Temperature and voltage stress dependent dielectric relaxation process of the doped Ba0.67Sr0.33TiO3 ceramics

    NASA Astrophysics Data System (ADS)

    Yan, Shiguang; Mao, Chaoliang; Wang, Genshui; Yao, Chunhua; Cao, Fei; Dong, Xianlin

    2013-09-01

    The current decay characteristic in the time domain is studied in Y3+ and Mn2+ modified Ba0.67Sr0.33TiO3 ceramics under different temperatures (25 °C-213 °C) and voltage stresses (0 V-800 V). The decay of the current is correlated with the overlapping of the relaxation process and leakage current. With respect to the inherent remarkable dielectric nonlinearity, a simple method through curve fitting is derived to differentiate these two currents. Two mechanisms of the relaxation process are proposed: a distribution of the potential barriers mode around room temperature and an electron injection mode at the elevated temperature of 110 °C.

  14. Sliding mode observers for automotive alternator

    NASA Astrophysics Data System (ADS)

    Chen, De-Shiou

    Estimator development for synchronous rectification of the automotive alternator is a desirable approach for estimating alternator's back electromotive forces (EMFs) without a direct mechanical sensor of the rotor position. Recent theoretical studies show that estimation of the back EMF may be observed based on system's phase current model by sensing electrical variables (AC phase currents and DC bus voltage) of the synchronous rectifier. Observer design of the back EMF estimation has been developed for constant engine speed. In this work, we are interested in nonlinear observer design of the back EMF estimation for the real case of variable engine speed. Initial back EMF estimate can be obtained from a first-order sliding mode observer (SMO) based on the phase current model. A fourth-order nonlinear asymptotic observer (NAO), complemented by the dynamics of the back EMF with time-varying frequency and amplitude, is then incorporated into the observer design for chattering reduction. Since the cost of required phase current sensors may be prohibitive, the most applicable approach in real implementation by measuring DC current of the synchronous rectifier is carried out in the dissertation. It is shown that the DC link current consists of sequential "windows" with partial information of the phase currents, hence, the cascaded NAO is responsible not only for the purpose of chattering reduction but also for necessarily accomplishing the process of estimation. Stability analyses of the proposed estimators are considered for most linear and time-varying cases. The stability of the NAO without speed information is substantiated by both numerical and experimental results. Prospective estimation algorithms for the case of battery current measurements are investigated. Theoretical study indicates that the convergence of the proposed LAO may be provided by high gain inputs. Since the order of the LAO/NAO for the battery current case is one order higher than that of the link current measurements, it is hard to find moderate values of the input gains for the real-time sampled-data systems. Technical difficulties in implementation of such high order discrete-time nonlinear estimators have been discussed. Directions of further investigations have been provided.

  15. Biological Information Document, Radioactive Liquid Waste Treatment Facility

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

    Biggs, J.

    1995-12-31

    This document is intended to act as a baseline source material for risk assessments which can be used in Environmental Assessments and Environmental Impact Statements. The current Radioactive Liquid Waste Treatment Facility (RLWTF) does not meet current General Design Criteria for Non-reactor Nuclear Facilities and could be shut down affecting several DOE programs. This Biological Information Document summarizes various biological studies that have been conducted in the vicinity of new Proposed RLWTF site and an Alternative site. The Proposed site is located on Mesita del Buey, a mess top, and the Alternative site is located in Mortandad Canyon. The Proposedmore » Site is devoid of overstory species due to previous disturbance and is dominated by a mixture of grasses, forbs, and scattered low-growing shrubs. Vegetation immediately adjacent to the site is a pinyon-juniper woodland. The Mortandad canyon bottom overstory is dominated by ponderosa pine, willow, and rush. The south-facing slope was dominated by ponderosa pine, mountain mahogany, oak, and muhly. The north-facing slope is dominated by Douglas fir, ponderosa pine, and oak. Studies on wildlife species are limited in the vicinity of the proposed project and further studies will be necessary to accurately identify wildlife populations and to what extent they utilize the project area. Some information is provided on invertebrates, amphibians and reptiles, and small mammals. Additional species information from other nearby locations is discussed in detail. Habitat requirements exist in the project area for one federally threatened wildlife species, the peregrine falcon, and one federal candidate species, the spotted bat. However, based on surveys outside of the project area but in similar habitats, these species are not expected to occur in either the Proposed or Alternative RLWTF sites. Habitat Evaluation Procedures were used to evaluate ecological functioning in the project area.« less

  16. GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications

    NASA Astrophysics Data System (ADS)

    Lemaréchal, Yannick; Bert, Julien; Falconnet, Claire; Després, Philippe; Valeri, Antoine; Schick, Ulrike; Pradier, Olivier; Garcia, Marie-Paule; Boussion, Nicolas; Visvikis, Dimitris

    2015-07-01

    In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding to be routinely used. In this work we implemented and evaluated an accurate and fast MCS on Graphics Processing Units (GPU) for brachytherapy low dose rate (LDR) applications. A previously proposed Geant4 based MCS framework implemented on GPU (GGEMS) was extended to include a hybrid GPU navigator, allowing navigation within voxelized patient specific images and analytically modeled 125I seeds used in LDR brachytherapy. In addition, dose scoring based on track length estimator including uncertainty calculations was incorporated. The implemented GGEMS-brachy platform was validated using a comparison with Geant4 simulations and reference datasets. Finally, a comparative dosimetry study based on the current clinical standard (TG43) and the proposed platform was performed on twelve prostate cancer patients undergoing LDR brachytherapy. Considering patient 3D CT volumes of 400  × 250  × 65 voxels and an average of 58 implanted seeds, the mean patient dosimetry study run time for a 2% dose uncertainty was 9.35 s (≈500 ms 10-6 simulated particles) and 2.5 s when using one and four GPUs, respectively. The performance of the proposed GGEMS-brachy platform allows envisaging the use of Monte Carlo simulation based dosimetry studies in brachytherapy compatible with clinical practice. Although the proposed platform was evaluated for prostate cancer, it is equally applicable to other LDR brachytherapy clinical applications. Future extensions will allow its application in high dose rate brachytherapy applications.

  17. Special Education Teacher Education Research: Current Status and Future Directions

    ERIC Educational Resources Information Center

    Sindelar, Paul T.; Brownell, Mary T.; Billingsley, Bonnie

    2010-01-01

    In this article, the authors propose an agenda for special education teacher education researchers, with particular attention to policy work and studies of innovations in pre-service preparation, induction and mentoring, and professional development. Because previous research is limited and unfocused, the foundation for future research is weak,…

  18. A Bibliography of Agriculture and Rural Life in Yemen.

    ERIC Educational Resources Information Center

    Swanjord, Don Edward

    Intended as a key to current work in agriculture in Yemen, this bibliography cites more than 520 resources produced since 1963 including monographs, journal articles, theses and dissertations, conference papers, case studies, reports, proposals, surveys, bibliographies, and United Nations publications. Foreign language materials in German, French,…

  19. Assessing Effective Attributes of Followers in a Leadership Process

    ERIC Educational Resources Information Center

    Antelo, Absael; Prilipko, Evgenia V.; Sheridan-Pereira, Margaret

    2010-01-01

    Followership, being an understudied concept, raises fundamental questions: How did followership develop? Why do people submit into becoming followers? The developmental trajectory for the development of individual attributes is as yet, uncharted. Current study provides an overview of assessed attributes of followers, as proposed by Antelo (2010).…

  20. The Relevance of Theories of the Policy Process to Educational Decision-Making.

    ERIC Educational Resources Information Center

    Ryan, R. J.

    1985-01-01

    Two case studies of educational decision making are used to test the utility of some current theories of the policy-formation process; a framework for the application of these theories is proposed; and the merits of applying existing theories before seeking new paradigms are stressed. (MSE)

  1. Academic Library Consortium in Jordan: An Evaluation Study

    ERIC Educational Resources Information Center

    Ahmed, Mustafa H.; Suleiman, Raid Jameel

    2013-01-01

    Purpose: Due to the current financial and managerial difficulties that are encountered by libraries in public universities in Jordan and the geographical diffusion of these academic institutions, the idea of establishing a consortium was proposed by the Council of Higher Education to combine these libraries. This article reviews the reality of…

  2. A Developmental Sequence Model to University Adjustment of International Undergraduate Students

    ERIC Educational Resources Information Center

    Chavoshi, Saeid; Wintre, Maxine Gallander; Dentakos, Stella; Wright, Lorna

    2017-01-01

    The current study proposes a Developmental Sequence Model to University Adjustment and uses a multifaceted measure, including academic, social and psychological adjustment, to examine factors predictive of undergraduate international student adjustment. A hierarchic regression model is carried out on the Student Adaptation to College Questionnaire…

  3. Universal Developmental Screening: Preliminary Studies in Galicia, Spain

    ERIC Educational Resources Information Center

    Sarmiento Campos, Jose A.; Squires, Jane; Ponte, Jaime

    2011-01-01

    "A_Tempo" is a research project that is currently under development in Galicia, an autonomous community of Spain. Its main aim is to propose an effective universal screening procedure for early identification of developmental disorders in children from zero to three years of age who attend Galician pre-primary schools.…

  4. Temperament Theory and the Study of Cognition-Emotion Interactions across Development

    ERIC Educational Resources Information Center

    Henderson, Heather A.; Wachs, Theodore D.

    2007-01-01

    In this paper we review current definitions and measurement approaches used to assess individual differences in children's temperament. We review the neural bases of temperamental reactivity and self-regulation and propose that these constructs provide a framework for examining individual differences and developmental change in emotion-cognition…

  5. Instructional Design for the Future of Undergraduate Journalism Education

    ERIC Educational Resources Information Center

    Farmer, Christopher J.

    2012-01-01

    In the face of communication changes brought on by technology, journalism curriculum needs restructuring while staying true to its core values. Using an instructional design framework, and a case study, this paper proposes a journalism education based on Esser's spheres of influence. Current practices and principles are discussed. A literature…

  6. Estimating Slope and Level Change in N = 1 Designs

    ERIC Educational Resources Information Center

    Solanas, Antonio; Manolov, Rumen; Onghena, Patrick

    2010-01-01

    The current study proposes a new procedure for separately estimating slope change and level change between two adjacent phases in single-case designs. The procedure eliminates baseline trend from the whole data series before assessing treatment effectiveness. The steps necessary to obtain the estimates are presented in detail, explained, and…

  7. Vocational Education, The Bridge Between Man and His Work.

    ERIC Educational Resources Information Center

    Larson, Milton E.; Blake, Duane L.

    This conference was one of six regional meetings on implications of current proposals on vocational education for industry, education, and legislation sponsored by the University of Wisconsin Center for Studies in Vocational and Technical Education. Approximately 209 persons, mostly educators, attended. Presentations included in the document are:…

  8. Mobbing, Organizational Identification, and Perceived Support: Evidence from a Higher Education Institution

    ERIC Educational Resources Information Center

    Coskuner, Selda; Costur, Recai; Bayhan-Karapinar, Pinar; Metin-Camgoz, Selin; Ceylan, Savas; Demirtas-Zorbaz, Selen; Aktas, Emine Feyza; Ciffiliz, Gonca

    2018-01-01

    Purpose: The aim of the current study is twofold. First, it investigates the relationship between mobbing and organizational identification (OI) as an organizational attitude. Second, it explores the moderating effect of perceived organizational support (POS) on the relationship between mobbing and organizational identification. We proposed that…

  9. Spiritual Assessment of Students at Conservative Wesleyan-Arminian Bible Colleges

    ERIC Educational Resources Information Center

    Cooley, Timothy L., Sr.

    2011-01-01

    The current study proposed to determine the level of spiritual transformation in students at conservative Wesleyan-Arminian Bible colleges and the association of spiritual transformation with selected Bible college activities. A quantitative survey was designed, validated, and implemented to measure students' self-reported levels of spiritual…

  10. A gene expression biomarker identifies in vitro and in vivo ERα modulators in a human gene expression compendium

    EPA Science Inventory

    We propose the use of gene expression profiling to complement the chemical characterization currently based on HTS assay data and present a case study relevant to the Endocrine Disruptor Screening Program. We have developed computational methods to identify estrogen receptor &alp...

  11. Managing Student Affairs Programs: Methods, Models, Muddles.

    ERIC Educational Resources Information Center

    Deegan, William L.

    Management processes and problems are examined in a variety of student affairs contexts. This book (1) proposes a theoretical framework for the analysis of management functions in colleges and universities, (2) studies the practice of management in several different student affairs contexts to uncover current practices, issues, problems, and…

  12. Grafting Technique to Eliminate Rootstock Suckering of Grafted Tomatoes

    USDA-ARS?s Scientific Manuscript database

    Vegetable grafting has been proposed as a technique for avoiding disease problems in tomatoes in open field production. In this study we investigated the current use of grafting in an open field scenario and found a serious problem with the grafting techniques. In the Fall of 2007, commercially pr...

  13. Anxiety Sensitivity in Children of Panic Disorder Patients

    ERIC Educational Resources Information Center

    van Beek, N.; Perna, G.; Schruers, K.; Muris, P.; Griez, E.

    2005-01-01

    Anxiety sensitivity (AS), which refers to the tendency to interpret anxiety-related bodily sensations as having potentially harmful somatic, psychological or social consequences, has been proposed as a vulnerability factor for the development of panic disorder (PD). The current study examined the anxiety sensitivity levels in children of parents…

  14. Young L2 Learners' Performance on a Novel Morpheme Task

    ERIC Educational Resources Information Center

    Kohnert, Kathryn; Danahy, Kerry

    2007-01-01

    The teaching of an invented language rule has been proposed as a possible non-biased, language-independent assessment technique useful in differentiating young L2 learners with specific language impairment from their typically developing peers. The current study explores these notions by testing typically developing sequential bilingual children's…

  15. Negotiation Process Analysis: A Research and Training Tool.

    ERIC Educational Resources Information Center

    Williams, Timothy

    This paper proposes the use of interaction process analysis to study negotiation behaviors. Following a review of current literature in the field, the paper presents a theoretical framework for the analysis of both labor/management and social negotiation processes. Central to the framework described are two systems of activities that together…

  16. Examining South Korea's Elementary Physical Education Performance Assessment Using Assessment Literacy Perspectives

    ERIC Educational Resources Information Center

    Park, Yongnam

    2017-01-01

    This study examines the issues pertaining to South Korea's elementary physical education (PE) performance assessment, using an assessment literacy (Hay & Penney, 2013) perspective to propose future directions. Eight elementary teachers currently teaching PE were selected as participants. Data were collected through semi-structured in-depth…

  17. 77 FR 55217 - Submission for OMB Review; Comment Request: Cognitive Testing of Instrumentation and Materials...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-07

    ...; Comment Request: Cognitive Testing of Instrumentation and Materials for the Population Assessment of..., unless it displays a currently valid OMB control number. Proposed Collection: Title: Cognitive Testing of... Administration (FDA). NIDA is requesting generic approval from OMB for cognitive testing of the PATH study's...

  18. Teaching Culture: The Challenges and Opportunities of International Public Relations.

    ERIC Educational Resources Information Center

    George, Amiso M.

    2003-01-01

    Focuses on the challenges and opportunities for international public relations practice. Looks at current United States-Arab relations issues in international crisis communication. Discusses those issues, especially the role of culture and media. Proposes strategies including a case study that teachers can use to help students become effective…

  19. Pharmaceutical cost control in primary care: opinion and contributions by healthcare professionals

    PubMed Central

    2009-01-01

    Background Strategies adopted by health administrations and directed towards drug cost control in primary care (PC) can, according to earlier studies, generate tension between health administrators and healthcare professionals. This study collects and analyzes the opinions of general practitioners (GPs) regarding current cost control measures as well as their proposals for improving the effectiveness of these measures. Methods A qualitative exploratory study was carried out using 11 focus groups composed of GPs from the Spanish regions of Aragon, Catalonia and the Balearic Islands. A semi-structured guide was applied in obtaining the GPs' opinions. The transcripts of the dialogues were analyzed by two investigators who independently considered categorical and thematic content. The results were supervised by other members of the team, with overall responsibility assigned to the team leader. Results GPs are conscious of their public responsibility with respect to pharmaceutical cost, but highlight the need to spread responsibility for cost control among the different actors of the health system. They insist on implementing measures to improve the quality of prescriptions, avoiding mere quantitative evaluations of prescription costs. They also suggest moving towards the self-management of the pharmaceutical budget by each health centre itself, as a means to design personalized incentives to improve their outcomes. These proposals need to be considered by the health administration in order to pre-empt the feelings of injustice, impotence, frustration and lack of motivation that currently exist among GPs as a result of the implemented measures. Conclusion Future investigations should be oriented toward strategies that involve GPs in the planning and management of drug cost control mechanisms. The proposals in this study may be considered by the health administration as a means to move toward the rational use of drugs while avoiding concerns about injustice and feelings of impotence on the part of the GPs, which can lead to lack of interest in and disaffection with the current measures. PMID:19922620

  20. Maximum power extraction under different vector-control schemes and grid-synchronization strategy of a wind-driven Brushless Doubly-Fed Reluctance Generator.

    PubMed

    Mousa, Mohamed G; Allam, S M; Rashad, Essam M

    2018-01-01

    This paper proposes an advanced strategy to synchronize the wind-driven Brushless Doubly-Fed Reluctance Generator (BDFRG) to the grid-side terminals. The proposed strategy depends mainly upon determining the electrical angle of the grid voltage, θ v and using the same transformation matrix of both the power winding and grid sides to ensure that the generated power-winding voltage has the same phase-sequence of the grid-side voltage. On the other hand, the paper proposes a vector-control (power-winding flux orientation) technique for maximum wind-power extraction under two schemes summarized as; unity power-factor operation and minimum converter-current. Moreover, a soft-starting method is suggested to avoid the employed converter over-current. The first control scheme is achieved by adjusting the command power-winding reactive power at zero for a unity power-factor operation. However, the second scheme depends on setting the command d-axis control-winding current at zero to maximize the ratio of the generator electromagnetic-torque per the converter current. This enables the system to get a certain command torque under minimum converter current. A sample of the obtained simulation and experimental results is presented to check the effectiveness of the proposed control strategies. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Non-Destructive Current Sensing for Energy Efficiency Monitoring in Buildings with Environmental Certification

    PubMed Central

    Mota, Lia Toledo Moreira; Mota, Alexandre de Assis; Coiado, Lorenzo Campos

    2015-01-01

    Nowadays, buildings environmental certifications encourage the implementation of initiatives aiming to increase energy efficiency in buildings. In these certification systems, increased energy efficiency arising from such initiatives must be demonstrated. Thus, a challenge to be faced is how to check the increase in energy efficiency related to each of the employed initiatives without a considerable building retrofit. In this context, this work presents a non-destructive method for electric current sensing to assess implemented initiatives to increase energy efficiency in buildings with environmental certification. This method proposes the use of a sensor that can be installed directly in the low voltage electrical circuit conductors that are powering the initiative under evaluation, without the need for reforms that result in significant costs, repair, and maintenance. The proposed sensor consists of three elements: an air-core transformer current sensor, an amplifying/filtering stage, and a microprocessor. A prototype of the proposed sensor was developed and tests were performed to validate this sensor. Based on laboratory tests, it was possible to characterize the proposed current sensor with respect to the number of turns and cross-sectional area of the primary and secondary coils. Furthermore, using the Least Squares Method, it was possible to determine the efficiency of the air core transformer current sensor (the best efficiency found, considering different test conditions, was 2%), which leads to a linear output response. PMID:26184208

  2. Non-Destructive Current Sensing for Energy Efficiency Monitoring in Buildings with Environmental Certification.

    PubMed

    Mota, Lia Toledo Moreira; Mota, Alexandre de Assis; Coiado, Lorenzo Campos

    2015-07-10

    Nowadays, buildings environmental certifications encourage the implementation of initiatives aiming to increase energy efficiency in buildings. In these certification systems, increased energy efficiency arising from such initiatives must be demonstrated. Thus, a challenge to be faced is how to check the increase in energy efficiency related to each of the employed initiatives without a considerable building retrofit. In this context, this work presents a non-destructive method for electric current sensing to assess implemented initiatives to increase energy efficiency in buildings with environmental certification. This method proposes the use of a sensor that can be installed directly in the low voltage electrical circuit conductors that are powering the initiative under evaluation, without the need for reforms that result in significant costs, repair, and maintenance. The proposed sensor consists of three elements: an air-core transformer current sensor, an amplifying/filtering stage, and a microprocessor. A prototype of the proposed sensor was developed and tests were performed to validate this sensor. Based on laboratory tests, it was possible to characterize the proposed current sensor with respect to the number of turns and cross-sectional area of the primary and secondary coils. Furthermore, using the Least Squares Method, it was possible to determine the efficiency of the air core transformer current sensor (the best efficiency found, considering different test conditions, was 2%), which leads to a linear output response.

  3. Possibility of material cost reduction toward development of low-cost second-generation superconducting wires

    NASA Astrophysics Data System (ADS)

    Ichinose, Ataru; Horii, Shigeru; Doi, Toshiya

    2017-10-01

    Two approaches to reducing the material cost of second-generation superconducting wires are proposed in this paper: (1) instead of the electrical stabilizing layers of silver and copper presently used on the superconducting layer, a Nb-doped SrTiO3 conductive buffer layer and cube-textured Cu are proposed as an advanced architecture, and (2) the use of an electromagnetic (EM) steel tape as a metal substrate of coated conductors in a conventional architecture. In structures fabricated without using electrical stabilizing layers on the superconducting layer, the critical current density achieved at 77 K in a self-field was approximately 2.6 MA/cm2. On the other hand, in the case of using EM steel tapes, although the critical current density was far from practical at the current stage, the biaxial alignment of YBa2Cu3O y (YBCO) and buffer layers was realized without oxidation on the metal surface. In this study, the possibility of material cost reduction has been strongly indicated toward the development of low-cost second-generation superconducting wires in the near future.

  4. Study of current-mode active pixel sensor circuits using amorphous InSnZnO thin-film transistor for 50-μm pixel-pitch indirect X-ray imagers

    NASA Astrophysics Data System (ADS)

    Cheng, Mao-Hsun; Zhao, Chumin; Kanicki, Jerzy

    2017-05-01

    Current-mode active pixel sensor (C-APS) circuits based on amorphous indium-tin-zinc-oxide thin-film transistors (a-ITZO TFTs) are proposed for indirect X-ray imagers. The proposed C-APS circuits include a combination of a hydrogenated amorphous silicon (a-Si:H) p+-i-n+ photodiode (PD) and a-ITZO TFTs. Source-output (SO) and drain-output (DO) C-APS are investigated and compared. Acceptable signal linearity and high gains are realized for SO C-APS. APS circuit characteristics including voltage gain, charge gain, signal linearity, charge-to-current conversion gain, electron-to-voltage conversion gain are evaluated. The impact of the a-ITZO TFT threshold voltage shifts on C-APS is also considered. A layout for a pixel pitch of 50 μm and an associated fabrication process are suggested. Data line loadings for 4k-resolution X-ray imagers are computed and their impact on circuit performances is taken into consideration. Noise analysis is performed, showing a total input-referred noise of 239 e-.

  5. Immersion lithography: its history, current status and future prospects

    NASA Astrophysics Data System (ADS)

    Owa, Soichi; Nagasaka, Hiroyuki

    2008-11-01

    Since the 1980's, immersion exposure has been proposed several times. At the end of 1990's, however, these concepts were almost forgotten because other technologies, such as electron beam projection, EUVL, and 157 nm were believed to be more promising than immersion exposures. The current work in immersion lithography started in 2001 with the report of Switkes and Rothschild. Although their first proposal was at 157 nm wavelength, their report in the following year on 193 nm immersion with purified water turned out to be the turning point for the introduction of water-based 193 nm immersion lithography. In February, 2003, positive feasibility study results of 193 nm immersion were presented at the SPIE microlithography conference. Since then, the development of 193 nm immersion exposure tools accelerated. Currently (year 2008), multiple hyper NA (NA>1.0) scanners are generating mass production 45 nm half pitch devices in semiconductor manufacturing factories. As a future extension, high index immersion was studied over the past few years, but material development lagged more than expected, which resulted in the cancellation of high index immersion plans at scanner makers. Instead, double patterning, double dipole exposure, and customized illuminations techniques are expected as techniques to extend immersion for the 32 nm node and beyond.

  6. Many-Objective Reservoir Policy Identification and Refinement to Reduce Institutional Myopia in Water Management

    NASA Astrophysics Data System (ADS)

    Giuliani, M.; Herman, J. D.; Castelletti, A.; Reed, P. M.

    2013-12-01

    Institutional inertia strongly limits our ability to adapt water reservoir operations to better manage growing water demands as well as their associated uncertainties in a changing climate. Although it has long been recognized that these systems are generally framed in heterogeneous socio-economic contexts involving a myriad of conflicting, non-commensurable operating objectives, our broader understanding of the multiobjective consequences of current operating rules as well as their vulnerability to hydroclimatic uncertainties is severely limited. This study proposes a decision analytic framework to overcome policy inertia and myopia in complex river basin management contexts. The framework combines reservoir policy identification and many-objective optimization under uncertainty to characterize current operations and discover key tradeoffs between alternative policies for balancing evolving demands and system uncertainties. The approach is demonstrated on the Conowingo Dam, located within the Lower Susquehanna River, USA. The Lower Susquehanna River is an interstate water body that has been subject to intensive water management efforts due to the system's competing demands from urban water supply, atomic power plant cooling, hydropower production, and federally regulated environmental flows. Initially our proposed framework uses available streamflow observations to implicitly identify the Conowingo Dam's current but unknown operating policy. This baseline policy is identified by fitting radial basis functions to existing system dynamics. Our assumption in the baseline policy is that the dam operator is represented as a rational agent seeking to maximize primary operational objectives (i.e., guaranteeing the public water supply and maximizing the hydropower revenue). The quality of the identified baseline policy is evaluated by its ability to replicate historical release dynamics. Once identified, the historical baseline policy then provides a means of representing the decision preferences guiding current operations. Our results show that the estimated policy closely captures the dynamics of current releases and flows for the Lower Susquehanna. After identifying the historical baseline policy, our proposed decision analytic framework then combines evolutionary many-objective optimization with visual analytics to discover improved operating policies. Our Lower Susquehanna results confirm that the system's current history-based operations are negatively biased to overestimate the reliability of the reservoir's multi-sector services. Moreover, our proposed framework has successfully identified alternative reservoir policies that are more robust to hydroclimatic uncertainties while being capable of better addressing the tradeoffs across the Conowingo Dam's multi-sector services.

  7. Meta-analysis of quantitative pleiotropic traits for next-generation sequencing with multivariate functional linear models

    PubMed Central

    Chiu, Chi-yang; Jung, Jeesun; Chen, Wei; Weeks, Daniel E; Ren, Haobo; Boehnke, Michael; Amos, Christopher I; Liu, Aiyi; Mills, James L; Ting Lee, Mei-ling; Xiong, Momiao; Fan, Ruzong

    2017-01-01

    To analyze next-generation sequencing data, multivariate functional linear models are developed for a meta-analysis of multiple studies to connect genetic variant data to multiple quantitative traits adjusting for covariates. The goal is to take the advantage of both meta-analysis and pleiotropic analysis in order to improve power and to carry out a unified association analysis of multiple studies and multiple traits of complex disorders. Three types of approximate F -distributions based on Pillai–Bartlett trace, Hotelling–Lawley trace, and Wilks's Lambda are introduced to test for association between multiple quantitative traits and multiple genetic variants. Simulation analysis is performed to evaluate false-positive rates and power of the proposed tests. The proposed methods are applied to analyze lipid traits in eight European cohorts. It is shown that it is more advantageous to perform multivariate analysis than univariate analysis in general, and it is more advantageous to perform meta-analysis of multiple studies instead of analyzing the individual studies separately. The proposed models require individual observations. The value of the current paper can be seen at least for two reasons: (a) the proposed methods can be applied to studies that have individual genotype data; (b) the proposed methods can be used as a criterion for future work that uses summary statistics to build test statistics to meta-analyze the data. PMID:28000696

  8. Meta-analysis of quantitative pleiotropic traits for next-generation sequencing with multivariate functional linear models.

    PubMed

    Chiu, Chi-Yang; Jung, Jeesun; Chen, Wei; Weeks, Daniel E; Ren, Haobo; Boehnke, Michael; Amos, Christopher I; Liu, Aiyi; Mills, James L; Ting Lee, Mei-Ling; Xiong, Momiao; Fan, Ruzong

    2017-02-01

    To analyze next-generation sequencing data, multivariate functional linear models are developed for a meta-analysis of multiple studies to connect genetic variant data to multiple quantitative traits adjusting for covariates. The goal is to take the advantage of both meta-analysis and pleiotropic analysis in order to improve power and to carry out a unified association analysis of multiple studies and multiple traits of complex disorders. Three types of approximate F -distributions based on Pillai-Bartlett trace, Hotelling-Lawley trace, and Wilks's Lambda are introduced to test for association between multiple quantitative traits and multiple genetic variants. Simulation analysis is performed to evaluate false-positive rates and power of the proposed tests. The proposed methods are applied to analyze lipid traits in eight European cohorts. It is shown that it is more advantageous to perform multivariate analysis than univariate analysis in general, and it is more advantageous to perform meta-analysis of multiple studies instead of analyzing the individual studies separately. The proposed models require individual observations. The value of the current paper can be seen at least for two reasons: (a) the proposed methods can be applied to studies that have individual genotype data; (b) the proposed methods can be used as a criterion for future work that uses summary statistics to build test statistics to meta-analyze the data.

  9. Ergonomics and design: traffic sign and street name sign.

    PubMed

    Moroni, Janaina Luisa da Silva; Aymone, José Luís Farinatti

    2012-01-01

    This work proposes a design methodology using ergonomics and anthropometry concepts applied to traffic sign and street name sign projects. Initially, a literature revision on cognitive ergonomics and anthropometry is performed. Several authors and their design methodologies are analyzed and the aspects to be considered in projects of traffic and street name signs are selected and other specific aspects are proposed for the design methodology. A case study of the signs of "Street of Antiques" in Porto Alegre city is presented. To do that, interviews with the population are made to evaluate the current situation of signs. After that, a new sign proposal with virtual prototyping is done using the developed methodology. The results obtained with new interviews about the proposal show the user satisfaction and the importance of cognitive ergonomics to development of this type of urban furniture.

  10. About increasing informativity of diagnostic system of asynchronous electric motor by extracting additional information from values of consumed current parameter

    NASA Astrophysics Data System (ADS)

    Zhukovskiy, Y.; Korolev, N.; Koteleva, N.

    2018-05-01

    This article is devoted to expanding the possibilities of assessing the technical state of the current consumption of asynchronous electric drives, as well as increasing the information capacity of diagnostic methods, in conditions of limited access to equipment and incompleteness of information. The method of spectral analysis of the electric drive current can be supplemented by an analysis of the components of the current of the Park's vector. The research of the hodograph evolution in the moment of appearance and development of defects was carried out using the example of current asymmetry in the phases of an induction motor. The result of the study is the new diagnostic parameters of the asynchronous electric drive. During the research, it was proved that the proposed diagnostic parameters allow determining the type and level of the defect. At the same time, there is no need to stop the equipment and taky it out of service for repair. Modern digital control and monitoring systems can use the proposed parameters based on the stator current of an electrical machine to improve the accuracy and reliability of obtaining diagnostic patterns and predicting their changes in order to improve the equipment maintenance systems. This approach can also be used in systems and objects where there are significant parasitic vibrations and unsteady loads. The extraction of useful information can be carried out in electric drive systems in the structure of which there is a power electric converter.

  11. Single Nanopore Investigations with Ion Conductance Microscopy

    PubMed Central

    Chen, Chiao-Chen; Zhou, Yi; Baker, Lane A.

    2011-01-01

    A three-electrode scanning ion conductance microscope (SICM) was used to investigate the local current-voltage properties of a single nanopore. In this experimental configuration, the response measured is a function of changes in the resistances involved in the pathways of ion migration. Single nanopore membranes utilized in this study were prepared with an epoxy painting procedure to isolate a single nanopore from a track-etch multi-pore membrane. Current-voltage responses measured with the SICM probe in the vicinity of a single nanopore were investigated in detail and agreed well with equivalent circuit models proposed in this study. With this modified SICM, the current-voltage responses characterized for the case of a single cylindrical pore and a single conical pore exhibit distinct conductance properties that originate from the geometry of nanopores. PMID:21923184

  12. 76 FR 13450 - Proposed Collection: Comment Request for Regulation Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ... comments concerning proposed regulation, REG-105346-03, Partnership Equity for Services. DATES: Written... . SUPPLEMENTARY INFORMATION: Title: Partnership Equity for Services. OMB Number: 1545-1947. Regulation Project... proposed regulation. Type of Review: Extension of a currently approved collection. Affected Public...

  13. 78 FR 46002 - Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-30

    ... DEPARTMENT OF THE TREASURY Community Development Financial Institutions Fund Proposed Collection... other Federal agencies to take this opportunity to comment on proposed information collections, as... Activities. Current Actions: There are no changes being made to this collection. Type of Review: Extension of...

  14. Accumulation of electric currents driving jetting events in the solar atmosphere

    NASA Astrophysics Data System (ADS)

    Vargas Domínguez, S.; Guo, Y.; Demoulin, P.; Schmieder, B.; Ding, M.; Liu, Y.

    2013-12-01

    The solar atmosphere is populated with a wide variety of structures and phenomena at different spatial and temporal scales. Explosive phenomena are of particular interest due to their contribution to the atmosphere's energy budget and their implications, e.g. coronal heating. Recent instrumental developments have provided important observations and therefore new insights for tracking the dynamic evolution of the solar atmosphere. Jets of plasma are frequently observed in the solar corona and are thought to be a consequence of magnetic reconnection, however, the physics involved is not fully understood. Unprecedented observations (EUV and vector magnetic fields) are used to study solar jetting events, from which we derive the magnetic flux evolution, the photospheric velocity field, and the vertical electric current evolution. The evolution of magnetic parasitic polarities displaying diverging flows are detected to trigger recurrent jets in a solar regionon 17 September 2010. The interaction drive the build up of electric currents. Observed diverging flows are proposed to build continuously such currents. Magnetic reconnection is proposed to occur periodically, in the current layer created between the emerging bipole and the large scale active region field. SDO/AIA EUV composite images. Upper: SDO/AIA 171 Å image overlaid by the line-of-sight magnetic field observed at the same time as that of the 171 Å image. Lower: Map of photospheric transverse velocities derived from LCT analysis with the HMI magnetograms.

  15. Unwrapping eddy current compensation: improved compensation of eddy current induced baseline shifts in high-resolution phase-contrast MRI at 9.4 Tesla.

    PubMed

    Espe, Emil K S; Zhang, Lili; Sjaastad, Ivar

    2014-10-01

    Phase-contrast MRI (PC-MRI) is a versatile tool allowing evaluation of in vivo motion, but is sensitive to eddy current induced phase offsets, causing errors in the measured velocities. In high-resolution PC-MRI, these offsets can be sufficiently large to cause wrapping in the baseline phase, rendering conventional eddy current compensation (ECC) inadequate. The purpose of this study was to develop an improved ECC technique (unwrapping ECC) able to handle baseline phase discontinuities. Baseline phase discontinuities are unwrapped by minimizing the spatiotemporal standard deviation of the static-tissue phase. Computer simulations were used for demonstrating the theoretical foundation of the proposed technique. The presence of baseline wrapping was confirmed in high-resolution myocardial PC-MRI of a normal rat heart at 9.4 Tesla (T), and the performance of unwrapping ECC was compared with conventional ECC. Areas of phase wrapping in static regions were clearly evident in high-resolution PC-MRI. The proposed technique successfully eliminated discontinuities in the baseline, and resulted in significantly better ECC than the conventional approach. We report the occurrence of baseline phase wrapping in PC-MRI, and provide an improved ECC technique capable of handling its presence. Unwrapping ECC offers improved correction of eddy current induced baseline shifts in high-resolution PC-MRI. Copyright © 2013 Wiley Periodicals, Inc.

  16. 77 FR 4366 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Current...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ... for OMB Review; Comment Request; Current Population Survey Disability Supplement ACTION: Notice... information collection request (ICR) proposal titled, ``Current Population Survey Disability Supplement,'' to... Current Population Survey (CPS) Disability Supplement will provide information on labor force...

  17. Macroscopic neural mass model constructed from a current-based network model of spiking neurons.

    PubMed

    Umehara, Hiroaki; Okada, Masato; Teramae, Jun-Nosuke; Naruse, Yasushi

    2017-02-01

    Neural mass models (NMMs) are efficient frameworks for describing macroscopic cortical dynamics including electroencephalogram and magnetoencephalogram signals. Originally, these models were formulated on an empirical basis of synaptic dynamics with relatively long time constants. By clarifying the relations between NMMs and the dynamics of microscopic structures such as neurons and synapses, we can better understand cortical and neural mechanisms from a multi-scale perspective. In a previous study, the NMMs were analytically derived by averaging the equations of synaptic dynamics over the neurons in the population and further averaging the equations of the membrane-potential dynamics. However, the averaging of synaptic current assumes that the neuron membrane potentials are nearly time invariant and that they remain at sub-threshold levels to retain the conductance-based model. This approximation limits the NMM to the non-firing state. In the present study, we newly propose a derivation of a NMM by alternatively approximating the synaptic current which is assumed to be independent of the membrane potential, thus adopting a current-based model. Our proposed model releases the constraint of the nearly constant membrane potential. We confirm that the obtained model is reducible to the previous model in the non-firing situation and that it reproduces the temporal mean values and relative power spectrum densities of the average membrane potentials for the spiking neurons. It is further ensured that the existing NMM properly models the averaged dynamics over individual neurons even if they are spiking in the populations.

  18. Real life working shift assignment problem

    NASA Astrophysics Data System (ADS)

    Sze, San-Nah; Kwek, Yeek-Ling; Tiong, Wei-King; Chiew, Kang-Leng

    2017-07-01

    This study concerns about the working shift assignment in an outlet of Supermarket X in Eastern Mall, Kuching. The working shift assignment needs to be solved at least once in every month. Current approval process of working shifts is too troublesome and time-consuming. Furthermore, the management staff cannot have an overview of manpower and working shift schedule. Thus, the aim of this study is to develop working shift assignment simulation and propose a working shift assignment solution. The main objective for this study is to fulfill manpower demand at minimum operation cost. Besides, the day off and meal break policy should be fulfilled accordingly. Demand based heuristic is proposed to assign working shift and the quality of the solution is evaluated by using the real data.

  19. Thermodynamics analysis of diffusion in spark plasma sintering welding Cr3C2 and Ni

    NASA Astrophysics Data System (ADS)

    Zhang, Fan; Zhang, Jinyong; Leng, Xiaoxuan; Lei, Liwen; Fu, Zhengyi

    2017-03-01

    Spark plasma sintering (SPS) welding of chromium carbide (Cr3C2) and nickel (Ni) was used to investigate the atomic diffusion caused by bypassing current. It was found that the diffusion coefficient with bypassing current was enhanced by almost 3.57 times over that without bypassing current. Different from the previous researches, the thermodynamics analysis conducted herein showed that the enhancement included a current direction-independent part besides the known current direction-dependent part. A local temperature gradient (LTG) model was proposed to explain the current direction-independent effect. Assuming that the LTG was mainly due to the interfacial electric resistance causing heterogeneous Joule heating, the theoretical results were in good agreement with the experimental results both in the present and previous studies. This new LTG model provides a reasonable physical meaning for the low-temperature advantage of SPS welding and should be useful in a wide range of applications.

  20. New Approach For Prediction Groundwater Depletion

    NASA Astrophysics Data System (ADS)

    Moustafa, Mahmoud

    2017-01-01

    Current approaches to quantify groundwater depletion involve water balance and satellite gravity. However, the water balance technique includes uncertain estimation of parameters such as evapotranspiration and runoff. The satellite method consumes time and effort. The work reported in this paper proposes using failure theory in a novel way to predict groundwater saturated thickness depletion. An important issue in the failure theory proposed is to determine the failure point (depletion case). The proposed technique uses depth of water as the net result of recharge/discharge processes in the aquifer to calculate remaining saturated thickness resulting from the applied pumping rates in an area to evaluate the groundwater depletion. Two parameters, the Weibull function and Bayes analysis were used to model and analyze collected data from 1962 to 2009. The proposed methodology was tested in a nonrenewable aquifer, with no recharge. Consequently, the continuous decline in water depth has been the main criterion used to estimate the depletion. The value of the proposed approach is to predict the probable effect of the current applied pumping rates on the saturated thickness based on the remaining saturated thickness data. The limitation of the suggested approach is that it assumes the applied management practices are constant during the prediction period. The study predicted that after 300 years there would be an 80% probability of the saturated aquifer which would be expected to be depleted. Lifetime or failure theory can give a simple alternative way to predict the remaining saturated thickness depletion with no time-consuming processes such as the sophisticated software required.

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