Sample records for demonstrate improved performance

  1. Performance improvement in the JCAHO environment of care.

    PubMed

    Hill, Scott A

    2002-01-01

    Using security management to demonstrate performance improvement for JCAHO can be a viable option. The article illustrates how a program for reducing theft became the basis for demonstrating performance improvement.

  2. Electrolytes for Use in High Energy Lithium-ion Batteries with Wide Operating Temperature Range

    NASA Technical Reports Server (NTRS)

    Smart, Marshall C.; Ratnakumar, B. V.; West, W. C.; Whitcanack, L. D.; Huang, C.; Soler, J.; Krause, F. C.

    2012-01-01

    Met programmatic milestones for program. Demonstrated improved performance with wide operating temperature electrolytes containing ester co-solvents (i.e., methyl butyrate) containing electrolyte additives in A123 prototype cells: Previously demonstrated excellent low temperature performance, including 11C rates at -30 C and the ability to perform well down to -60 C. Excellent cycle life at room temperature has been displayed, with over 5,000 cycles being demonstrated. Good high temperature cycle life performance has also been achieved. Demonstrated improved performance with methyl propionate-containing electrolytes in large capacity prototype cells: Demonstrated the wide operating temperature range capability in large cells (12 Ah), successfully scaling up technology from 0.25 Ah size cells. Demonstrated improved performance at low temperature and good cycle life at 40 C with methyl propionate-based electrolyte containing increasing FEC content and the use of LiBOB as an additive. Utilized three-electrode cells to investigate the electrochemical characteristics of high voltage systems coupled with wide operating temperature range electrolytes: From Tafel polarization measurements on each electrode, it is evident the NMC-based cathode displays poor lithium kinetics (being the limiting electrode). The MB-based formulations containing LiBOB delivered the best rate capability at low temperature, which is attributed to improved cathode kinetics. Whereas, the use of lithium oxalate as an additive lead to the highest reversible capacity and lower irreversible losses.

  3. Propulsion system-flight control integration and optimization: Flight evaluation and technology transition

    NASA Technical Reports Server (NTRS)

    Burcham, Frank W., Jr.; Gilyard, Glenn B.; Myers, Lawrence P.

    1990-01-01

    Integration of propulsion and flight control systems and their optimization offers significant performance improvements. Research programs were conducted which have developed new propulsion and flight control integration concepts, implemented designs on high-performance airplanes, demonstrated these designs in flight, and measured the performance improvements. These programs, first on the YF-12 airplane, and later on the F-15, demonstrated increased thrust, reduced fuel consumption, increased engine life, and improved airplane performance; with improvements in the 5 to 10 percent range achieved with integration and with no changes to hardware. The design, software and hardware developments, and testing requirements were shown to be practical.

  4. A plan for application system verification tests: The value of improved meteorological information, volume 1. [economic consequences of improved meteorological information

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The framework within which the Applications Systems Verification Tests (ASVTs) are performed and the economic consequences of improved meteorological information demonstrated is described. This framework considers the impact of improved information on decision processes, the data needs to demonstrate the economic impact of the improved information, the data availability, the methodology for determining and analyzing the collected data and demonstrating the economic impact of the improved information, and the possible methods of data collection. Three ASVTs are considered and program outlines and plans are developed for performing experiments to demonstrate the economic consequences of improved meteorological information. The ASVTs are concerned with the citrus crop in Florida, the cotton crop in Mississippi and a group of diverse crops in Oregon. The program outlines and plans include schedules, manpower estimates and funding requirements.

  5. The design and operating characteristics of an advanced 30-kW ammonia arcjet engine

    NASA Technical Reports Server (NTRS)

    Deininger, William D.; Pivirotto, Thomas J.; Brophy, John R.

    1987-01-01

    Experimental investigations were conducted to evaluate the effects of a contoured nozzle and modified cathode shape on ammonia arcjet engine performance. The contoured nozzle performance data were compared to the performance data of an arcjet which had a 38-deg included-angle, conical nozzle. Thrust improvements of up to 10 percent were demonstrated which corresponded to 3 percent improvements in specific impulse and 10 percent improvements in thrust efficiency. Performance characterizations for the modified cathode tip were conducted with the contoured nozzle arcjet. A uniform 15 percent decrease in arc voltage was demonstrated over a mass flow range of 0.175 to 0.350 g/s. A 4 percent improvement in thrust efficiency was noted at 22.0 kW.

  6. 42 CFR 475.104 - Requirements for demonstrating ability to perform review.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... review. 475.104 Section 475.104 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) QUALITY IMPROVEMENT ORGANIZATIONS QUALITY IMPROVEMENT ORGANIZATIONS Utilization and Quality Control Quality Improvement Organizations § 475.104 Requirements for demonstrating...

  7. Well-Being and the Social Environment of Work: A Systematic Review of Intervention Studies.

    PubMed

    Daniels, Kevin; Watson, David; Gedikli, Cigdem

    2017-08-16

    There is consistent evidence that a good social environment in the workplace is associated with employee well-being. However, there has been no specific review of interventions to improve well-being through improving social environments at work. We conducted a systematic review of such interventions, and also considered performance as an outcome. We found eight studies of interventions. Six studies were of interventions that were based on introducing shared social activities into workgroups. Six out of the six studies demonstrated improvements in well-being across the sample (five studies), or for an identifiable sub-group (one study). Four out of the five studies demonstrated improvements in social environments, and four out of the five studies demonstrated improvements in indicators of performance. Analysis of implementation factors indicated that the interventions based on shared activities require some external facilitation, favorable worker attitudes prior to the intervention, and several different components. We found two studies that focused on improving fairness perceptions in the workplace. There were no consistent effects of these interventions on well-being or performance. We conclude that there is some evidence that interventions that increase the frequency of shared activities between workers can improve worker well-being and performance. We offer suggestions for improving the evidence base.

  8. Well-Being and the Social Environment of Work: A Systematic Review of Intervention Studies

    PubMed Central

    Gedikli, Cigdem

    2017-01-01

    There is consistent evidence that a good social environment in the workplace is associated with employee well-being. However, there has been no specific review of interventions to improve well-being through improving social environments at work. We conducted a systematic review of such interventions, and also considered performance as an outcome. We found eight studies of interventions. Six studies were of interventions that were based on introducing shared social activities into workgroups. Six out of the six studies demonstrated improvements in well-being across the sample (five studies), or for an identifiable sub-group (one study). Four out of the five studies demonstrated improvements in social environments, and four out of the five studies demonstrated improvements in indicators of performance. Analysis of implementation factors indicated that the interventions based on shared activities require some external facilitation, favorable worker attitudes prior to the intervention, and several different components. We found two studies that focused on improving fairness perceptions in the workplace. There were no consistent effects of these interventions on well-being or performance. We conclude that there is some evidence that interventions that increase the frequency of shared activities between workers can improve worker well-being and performance. We offer suggestions for improving the evidence base. PMID:28813009

  9. Does the engagement of clinicians and organisations in research improve healthcare performance: a three-stage review

    PubMed Central

    Boaz, Annette; Hanney, Stephen; Jones, Teresa; Soper, Bryony

    2015-01-01

    Objective There is a widely held assumption that engagement by clinicians and healthcare organisations in research improves healthcare performance at various levels, but little direct empirical evidence has previously been collated. The objective of this study was to address the question: Does research engagement (by clinicians and organisations) improve healthcare performance? Methods An hourglass-shaped review was developed, consisting of three stages: (1) a planning and mapping stage; (2) a focused review concentrating on the core question of whether or not research engagement improves healthcare performance; and (3) a wider (but less systematic) review of papers identified during the two earlier stages, focusing on mechanisms. Results Of the 33 papers included in the focused review, 28 identified improvements in health services performance. Seven out of these papers reported some improvement in health outcomes, with others reporting improved processes of care. The wider review demonstrated that mechanisms such as collaborative and action research can encourage some progress along the pathway from research engagement towards improved healthcare performance. Organisations that have deliberately integrated the research function into organisational structures demonstrate how research engagement can, among other factors, contribute to improved healthcare performance. Conclusions Current evidence suggests that there is an association between the engagement of individuals and healthcare organisations in research and improvements in healthcare performance. The mechanisms through which research engagement might improve healthcare performance overlap and rarely act in isolation, and their effectiveness often depends on the context in which they operate. PMID:26656023

  10. Arsenic and Antimony Removal from Drinking Water by Adsorptive Media - U.S. EPA Demonstration Project at South Truckee Meadows General Improvement District (STMGID), NV, Final Performance Evaluation Report

    EPA Science Inventory

    This report documents the activities performed during and the results obtained from the operation of an arsenic and antimony removal technology demonstrated at the South Truckee Meadows General Improvement District (STMGID) in Washoe County, NV. The objectives of the project wer...

  11. Jet engine applications for materials with nanometer-scale dimensions

    NASA Technical Reports Server (NTRS)

    Appleby, J. W., Jr.

    1995-01-01

    The performance of advanced military and commercial gas turbine engines is often linked to advances in materials technology. High performance gas turbine engines being developed require major material advances in strength, toughness, reduced density and improved temperature capability. The emerging technology of nanostructured materials has enormous potential for producing materials with significant improvements in these properties. Extraordinary properties demonstrated in the laboratory include material strengths approaching theoretical limit, ceramics that demonstrate ductility and toughness, and materials with ultra-high hardness. Nanostructured materials and coatings have the potential for meeting future gas turbine engine requirements for improved performance, reduced weight and lower fuel consumption.

  12. Jet engine applications for materials with nanometer-scale dimensions

    NASA Technical Reports Server (NTRS)

    Appleby, J. W., Jr.

    1995-01-01

    The performance of advanced military and commercial gas turbine engines is often linked to advances in materials technology. High performance gas turbine engines being developed require major material advances in strength, toughness, reduced density and improved temperature capability. The emerging technology of nanostructured materials has enormous potential for producing materials with significant improvements in these properties. Extraordinary properties demonstrated in the laboratory include material strengths approaching theoretical limit, ceramics that demonstrate ductility and toughness, and material with ultra-high hardness. Nanostructured materials and coatings have the potential for meeting future gas turbine engine requirements for improved performance, reduced weight and lower fuel consumption.

  13. Subthalamic nucleus stimulation selectively improves motor and visual memory performance in Parkinson's disease.

    PubMed

    Mollion, Hélène; Dominey, Peter Ford; Broussolle, Emmanuel; Ventre-Dominey, Jocelyne

    2011-09-01

    Although the treatment of Parkinson's disease via subthalamic stimulation yields remarkable improvements in motor symptoms, its effects on memory function are less clear. In this context, we previously demonstrated dissociable effects of levodopa therapy on parkinsonian performance in spatial and nonspatial visual working memory. Here we used the same protocol with an additional, purely motor task to investigate visual memory and motor performance in 2 groups of patients with Parkinson's disease with or without subthalamic stimulation. In each stimulation condition, subjects performed a simple motor task and 3 successive cognitive tasks: 1 conditional color-response association task and 2 visual (spatial and nonspatial) working memory tasks. The Parkinson's groups were compared with a control group of age-matched healthy subjects. Our principal results demonstrated that (1) in the motor task, stimulated patients were significantly improved with respect to nonstimulated patients and did not differ significantly from healthy controls, and (2) in the cognitive tasks, stimulated patients were significantly improved with respect to nonstimulated patients, but both remained significantly impaired when compared with healthy controls. These results demonstrate selective effects of subthalamic stimulation on parkinsonian disorders of motor and visual memory functions, with clear motor improvement for stimulated patients and a partial improvement for their visual memory processing. Copyright © 2011 Movement Disorder Society.

  14. Improved Wide Operating Temperature Range of LiNiCoAiO2-based Li-ion Cells with Methyl Propionate-based Electrolytes

    NASA Technical Reports Server (NTRS)

    Smart, Marshall C.; Tomcsi, Michael R.; Hwang, C.; Whitcanack, L. D.; Bugga, Ratnakumar V.; Nagata, Mikito; Visco, Vince; Tsukamoto, Hisashi

    2012-01-01

    Demonstration of wide operating temperature range Li-ion electrolytes Methyl propionate-based wide operating temperature range electrolytes were demonstrated to provide dramatic improvement of the low temperature capability of Quallion prototype Li-ion cells (MCMB-LiNiCoAlO2). Some formulations were observed to deliver over 60% of the room temperature capacity using a 5C rate at - 40oC !! Represents over a 4-fold improvement over the baseline electrolyte system. Demonstrated operational capability of a number of systems over a wide temperature range (-40 to +70 C) Demonstrated reasonably good long term cycle life performance at high temperature (i.e., at +40deg and +50 C) A number of formulations containing electrolytes additives (i.e., FEC, VC, LiBOB, and lithium oxalate) have been shown to have enhanced lithium kinetics at low temperature and promising high temperature resilience. Demonstrated good performance in larger capacity (12 Ah) Quallion Li-ion cells with methyl propionate-based electrolytes. Current efforts focused upon performing life studies and the impact upon low temperature capability.

  15. Deodorants, value, and performance.

    PubMed

    Newcomer, L N

    1997-11-01

    For the health-care market, like the deodorant market, the message is clear: Add value or your product will not be competitive. For physicians of all specialties, the best way to add value is to measure and improve performance. Performance measurement is critical to improvement in health care. Without measurement, there can be no improvement in quality. Without improvement in quality, there is no added value. Oncologists can take at least two actions to add value for their health plans: (1) measure practice performance and demonstrate a quality improvement; and (2) become the personal-care physician for cancer patients.

  16. Acute, low-dose methamphetamine administration improves attention/information processing speed and working memory in methamphetamine-dependent individuals displaying poorer cognitive performance at baseline

    PubMed Central

    Mahoney, James J.; Jackson, Brian J.; Kalechstein, Ari D.; De La Garza, Richard; Newton, Thomas F.

    2012-01-01

    Abstinent methamphetamine (Meth) dependent individuals demonstrate poorer performance on tests sensitive to attention/information processing speed, learning and memory, and working memory when compared to non-Meth dependent individuals. The poorer performance on these tests may contribute to the morbidity associated with Meth-dependence. In light of this, we sought to determine the effects of acute, low-dose Meth administration on attention, working memory, and verbal learning and memory in 19 non-treatment seeking, Meth-dependent individuals. Participants were predominantly male (89%), Caucasian (63%), and cigarette smokers (63%). Following a four day, drug-free washout period, participants were given a single-blind intravenous infusion of saline, followed the next day by 30 mg of Meth. A battery of neurocognitive tasks was administered before and after each infusion, and performance on measures of accuracy and reaction time were compared between conditions. While acute Meth exposure did not affect test performance for the entire sample, participants who demonstrated relatively poor performance on these tests at baseline, identified using a median split on each test, showed significant improvement on measures of attention/information processing speed and working memory when administered Meth. Improved performance was seen on the following measures of working memory: choice reaction time task (p≤0.04), a 1-back task (p≤0.01), and a 2-back task (p≤0.04). In addition, those participants demonstrating high neurocognitive performance at baseline experienced similar or decreased performance following Meth exposure. These findings suggest that acute administration of Meth may temporarily improve Meth-associated neurocognitive performance in those individuals experiencing lower cognitive performance at baseline. As a result, stimulants may serve as a successful treatment for improving cognitive functioning in those Meth-dependent individuals experiencing neurocognitive impairment. PMID:21122811

  17. A comprehensive approach for diagnosing opportunities for improving the performance of a WWTP.

    PubMed

    Silva, C; Matos, J Saldanha; Rosa, M J

    2016-12-01

    High quality services of wastewater treatment require a continuous assessment and improvement of the technical, environmental and economic performance. This paper demonstrates a comprehensive approach for benchmarking wastewater treatment plants (WWTPs), using performance indicators (PIs) and indices (PXs), in a 'plan-do-check-act' cycle routine driven by objectives. The performance objectives herein illustrated were to diagnose the effectiveness and energy performance of an oxidation ditch WWTP. The PI and PX results demonstrated an effective and reliable oxidation ditch (good-excellent performance), and a non-reliable UV disinfection (unsatisfactory-excellent performance) related with influent transmittance and total suspended solids. The energy performance increased with the treated wastewater volume and was unsatisfactory below 50% of plant capacity utilization. The oxidation ditch aeration performed unsatisfactorily and represented 38% of the plant energy consumption. The results allowed diagnosing opportunities for improving the energy and economic performance considering the influent flows, temperature and concentrations, and for levering the WWTP performance to acceptable-good effectiveness, reliability and energy efficiency. Regarding the plant reliability for fecal coliforms, improvement of UV lamp maintenance and optimization of the UV dose applied and microscreen recommissioning were suggested.

  18. Performance Improvement Processes.

    ERIC Educational Resources Information Center

    1997

    This document contains four papers from a symposium on performance improvement processes. In "Never the Twain Shall Meet?: A Glimpse into High Performance Work Practices and Downsizing" (Laurie J. Bassi, Mark E. Van Buren) evidence from a national cross-industry of more than 200 establishments is used to demonstrate that high-performance…

  19. Does the engagement of clinicians and organisations in research improve healthcare performance: a three-stage review.

    PubMed

    Boaz, Annette; Hanney, Stephen; Jones, Teresa; Soper, Bryony

    2015-12-09

    There is a widely held assumption that engagement by clinicians and healthcare organisations in research improves healthcare performance at various levels, but little direct empirical evidence has previously been collated. The objective of this study was to address the question: Does research engagement (by clinicians and organisations) improve healthcare performance? An hourglass-shaped review was developed, consisting of three stages: (1) a planning and mapping stage; (2) a focused review concentrating on the core question of whether or not research engagement improves healthcare performance; and (3) a wider (but less systematic) review of papers identified during the two earlier stages, focusing on mechanisms. Of the 33 papers included in the focused review, 28 identified improvements in health services performance. Seven out of these papers reported some improvement in health outcomes, with others reporting improved processes of care. The wider review demonstrated that mechanisms such as collaborative and action research can encourage some progress along the pathway from research engagement towards improved healthcare performance. Organisations that have deliberately integrated the research function into organisational structures demonstrate how research engagement can, among other factors, contribute to improved healthcare performance. Current evidence suggests that there is an association between the engagement of individuals and healthcare organisations in research and improvements in healthcare performance. The mechanisms through which research engagement might improve healthcare performance overlap and rarely act in isolation, and their effectiveness often depends on the context in which they operate. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  20. Progress Toward Adaptive Integration and Optimization of Automated and Neural Processing Systems: Establishing Neural and Behavioral Benchmarks of Optimized Performance

    DTIC Science & Technology

    2014-11-01

    Paradigm ............................................................................19 3.4 Collaborative BCI for Improving Overall Performance...interfaces ( BCIs ) provide the biggest improvement in performance? Can we demonstrate clear advantages with BCIs ? 2 2. Simulator Development and...stimuli in real time. Fig. 18 ROC curves for each subject after the combination of 2 trials 3.4 Collaborative BCI for Improving Overall

  1. CF6 Jet Engine Performance Improvement: High Pressure Turbine Active Clearance Control

    NASA Technical Reports Server (NTRS)

    Rich, S. E.; Fasching, W. A.

    1982-01-01

    An active clearance control system was developed which reduces fuel consumption and performance degradation. This system utilizes compressor discharge air during takeoff and fan discharge air during cruise to impinge on the shroud structure to improve the thermal response. The system was evaluated in component and engine tests. The test results demonstrated a performance improvement of 0.7 percent in cruise SFC.

  2. Macro vs micro level surgical quality improvement: a regional collaborative demonstrates the case for a national NSQIP initiative.

    PubMed

    Tepas, Joseph J; Kerwin, Andrew J; deVilla, Jhun; Nussbaum, Michael S

    2014-04-01

    The Florida Surgical Care Initiative (FSCI) is a quality improvement collaborative of the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) and the Florida Hospital Association. In the wake of a dramatic decrease in complications and cost documented over 15 months, we analyzed the semiannual measures reports (SAR) to determine whether this improvement was driven by specific institutions or was a global accomplishment by all participants. Reports from NSQIP were analyzed to determine rank change of participants. Odds ratio (OR) of observed-to-expected incidence of the 4 FSCI outcomes (catheter-associated urinary tract infection [CAUTI], surgical site infection [SSI], colorectal, and surgery in patients older than 65 years) were used to assess individual and group performance. Data from SAR 2 (October 2011 to April 2012) were compared with data from SAR 3 (May to July 2012). Poorly performing hospitals were tracked to determine evidence of improvement. Individual facility performance was evaluated by determining proportion of hospitals showing improved rank across all measures. Fifty-four hospitals were evaluated. SAR 2 reported 28,112 general and vascular surgical cases; SAR 3 added 10,784 more. The proportion of institutions with OR < 1 for each measure did not change significantly. Only urinary tract infection and colorectal measures demonstrated increased number of hospitals with OR < 1. Each institution that was a significant negative outlier in SAR 2 demonstrated improvement. Three of 54 hospitals demonstrated improvement across all 4 measures. Of 15 hospitals with improved performance across 3 measures, all included elderly surgery. The increase in quality achieved across this population of surgical patients was the result of a quality assessment process driven by NSQIP rather than disproportionate improvement of some raising the bar for all. The NSQIP process, applied collaboratively across a population by committed institutions, produces dramatic results. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Improvement of Cerebral Hypoperfusion with Levothyroxine Therapy in Hashimoto's Encephalopathy Demonstrated by 99mTc-HMPAO-SPECT

    PubMed Central

    Schnedl, Wolfgang J.; Mirzaei, Siroos; Wallner-Liebmann, Sandra J.; Tafeit, Erwin; Mangge, Harald; Krause, Robert; Lipp, Rainer W.

    2013-01-01

    Background Hashimoto's encephalopathy (HE) is a rare immune-mediated encephalopathy associated with autoimmune Hashimoto's thyroiditis. Objectives and Methods We report on a patient with HE and significant clinical improvement correlating with an increase in cerebral blood flow demonstrated by hexamethylpropyleneamine oxime (HMPAO) single-photon emission computed tomography (SPECT). HMPAO-SPECT was performed with 740 MBq of technetium-99m-HMPAO. To demonstrate the improvement in regional cerebral blood flow, individual regions of interest were drawn around visually diminished HMPAO uptake, the lesion to reference region ratio was calculated and transverse section images and semi-quantitative measurements were performed. Results We show a 5-year follow-up with significant clinical improvement, a 10-fold reduction in autoantibodies to thyroid peroxidase and an approximately 20% improvement in cerebral blood flow with HMPAO-SPECT. Conclusion Adequate levothyroxine treatment achieving and maintaining euthyroidism should be considered as therapy to lower autoantibodies and improve clinical outcome in patients with Hashimoto's thyroiditis and encephalopathy. PMID:24783049

  4. Component Repair Experiment-1: An Experiment Evaluating Electronic Component-Level Repair During Spaceflight

    NASA Technical Reports Server (NTRS)

    Easton, John W.; Struk, Peter M.

    2012-01-01

    The Component Repair Experiment-1 (CRE-1) examines the capability for astronauts to perform electronics repair tasks in space. The goal is to determine the current capabilities and limits for the crew, and to make recommendations to improve and expand the range of work that astronauts may perform. CRE-1 provided two-layer, functional circuit boards and replacement components, a small tool kit, written and video training materials, and 1 hr of hands on training for the crew slated to perform the experiment approximately 7 months prior to the mission. Astronauts Michael Fincke and Sandra Magnus performed the work aboard the International Space Station (ISS) in February and March 2009. The astronauts were able to remove and replace components successfully, demonstrating the feasibility of performing component-level electronics repairs within a spacecraft. Several unsuccessful tasks demonstrated areas in need of improvement. These include improved and longer training prior to a mission, an improved soldering iron with a higher operating temperature and steady power source, video training and practice boards for refresher work or practice before a repair, and improved and varied hand tools and containment system.

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

    Kisner, R.; Melin, A.; Burress, T.

    The objective of this project is to demonstrate improved reliability and increased performance made possible by deeply embedding instrumentation and controls (I&C) in nuclear power plant (NPP) components and systems. The project is employing a highly instrumented canned rotor, magnetic bearing, fluoride salt pump as its I&C technology demonstration platform. I&C is intimately part of the basic millisecond-by-millisecond functioning of the system; treating I&C as an integral part of the system design is innovative and will allow significant improvement in capabilities and performance. As systems become more complex and greater performance is required, traditional I&C design techniques become inadequate andmore » more advanced I&C needs to be applied. New I&C techniques enable optimal and reliable performance and tolerance of noise and uncertainties in the system rather than merely monitoring quasistable performance. Traditionally, I&C has been incorporated in NPP components after the design is nearly complete; adequate performance was obtained through over-design. By incorporating I&C at the beginning of the design phase, the control system can provide superior performance and reliability and enable designs that are otherwise impossible. This report describes the progress and status of the project and provides a conceptual design overview for the platform to demonstrate the performance and reliability improvements enabled by advanced embedded I&C.« less

  6. Piloted studies of Enhanced or Synthetic Vision display parameters

    NASA Technical Reports Server (NTRS)

    Harris, Randall L., Sr.; Parrish, Russell V.

    1992-01-01

    This paper summarizes the results of several studies conducted at Langley Research Center over the past few years. The purposes of these studies were to investigate parameters of pictorial displays and imaging sensors that affect pilot approach and landing performance. Pictorial displays have demonstrated exceptional tracking performance and improved the pilots' spatial awareness. Stereopsis cueing improved pilot flight performance and reduced pilot stress. Sensor image parameters such as increased field-of-view. faster image update rate, and aiding symbology improved flare initiation. Finer image resolution and magnification improved attitude control performance parameters.

  7. 12 CFR Appendix A to Part 345 - Ratings

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... (iv) Needs to improve. The FDIC rates a bank's lending performance “needs to improve” if, in general... FDIC rates a bank's investment performance “needs to improve” if, in general, it demonstrates: (A) A... to improve. The FDIC rates a bank's service performance “needs to improve” if, in general, the bank...

  8. 12 CFR Appendix A to Part 25 - Ratings

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... (iv) Needs to improve. The OCC rates a bank's lending performance “needs to improve” if, in general... OCC rates a bank's investment performance “needs to improve” if, in general, it demonstrates: (A) A... to improve. The OCC rates a bank's service performance “needs to improve” if, in general, the bank...

  9. Flight Test Comparison of Different Adaptive Augmentations for Fault Tolerant Control Laws for a Modified F-15 Aircraft

    NASA Technical Reports Server (NTRS)

    Burken, John J.; Hanson, Curtis E.; Lee, James A.; Kaneshige, John T.

    2009-01-01

    This report describes the improvements and enhancements to a neural network based approach for directly adapting to aerodynamic changes resulting from damage or failures. This research is a follow-on effort to flight tests performed on the NASA F-15 aircraft as part of the Intelligent Flight Control System research effort. Previous flight test results demonstrated the potential for performance improvement under destabilizing damage conditions. Little or no improvement was provided under simulated control surface failures, however, and the adaptive system was prone to pilot-induced oscillations. An improved controller was designed to reduce the occurrence of pilot-induced oscillations and increase robustness to failures in general. This report presents an analysis of the neural networks used in the previous flight test, the improved adaptive controller, and the baseline case with no adaptation. Flight test results demonstrate significant improvement in performance by using the new adaptive controller compared with the previous adaptive system and the baseline system for control surface failures.

  10. Designing Scholarships to Improve College Success: Final Report on the Performance-Based Scholarship Demonstration

    ERIC Educational Resources Information Center

    Mayer, Alexander K.; Patel, Reshma; Rudd, Timothy; Ratledge, Alyssa

    2015-01-01

    Performance-based scholarships have two main goals: (1) to give students more money for college; and (2) to provide incentives for academic progress. MDRC launched the Performance-Based Scholarship (PBS) Demonstration in 2008 to evaluate the effectiveness of these scholarships in a diverse set of states, institutions, and low-income student…

  11. Solid polymer electrolyte (SPE) fuel cell technology program, phase 2/2A. [testing and evaluations

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Test evaluations were performed on a fabricated single solid polymer electrolyte cell unit. The cell operated at increased current density and at higher performance levels. This improved performance was obtained through a combination of increased temperature, increased reactant pressures, improved activation techniques and improved thermal control over the baseline cell configuration. The cell demonstrated a higher acid content membrane which resulted in increased performance. Reduced catalyst loading and low cost membrane development showed encouraging results.

  12. Research in action: using positive deviance to improve quality of health care

    PubMed Central

    Bradley, Elizabeth H; Curry, Leslie A; Ramanadhan, Shoba; Rowe, Laura; Nembhard, Ingrid M; Krumholz, Harlan M

    2009-01-01

    Background Despite decades of efforts to improve quality of health care, poor performance persists in many aspects of care. Less than 1% of the enormous national investment in medical research is focused on improving health care delivery. Furthermore, when effective innovations in clinical care are discovered, uptake of these innovations is often delayed and incomplete. In this paper, we build on the established principle of 'positive deviance' to propose an approach to identifying practices that improve health care quality. Methods We synthesize existing literature on positive deviance, describe major alternative approaches, propose benefits and limitations of a positive deviance approach for research directed toward improving quality of health care, and describe an application of this approach in improving hospital care for patients with acute myocardial infarction. Results The positive deviance approach, as adapted for use in health care, presumes that the knowledge about 'what works' is available in existing organizations that demonstrate consistently exceptional performance. Steps in this approach: identify 'positive deviants,' i.e., organizations that consistently demonstrate exceptionally high performance in the area of interest (e.g., proper medication use, timeliness of care); study the organizations in-depth using qualitative methods to generate hypotheses about practices that allow organizations to achieve top performance; test hypotheses statistically in larger, representative samples of organizations; and work in partnership with key stakeholders, including potential adopters, to disseminate the evidence about newly characterized best practices. The approach is particularly appropriate in situations where organizations can be ranked reliably based on valid performance measures, where there is substantial natural variation in performance within an industry, when openness about practices to achieve exceptional performance exists, and where there is an engaged constituency to promote uptake of discovered practices. Conclusion The identification and examination of health care organizations that demonstrate positive deviance provides an opportunity to characterize and disseminate strategies for improving quality. PMID:19426507

  13. Acute, low-dose methamphetamine administration improves attention/information processing speed and working memory in methamphetamine-dependent individuals displaying poorer cognitive performance at baseline.

    PubMed

    Mahoney, James J; Jackson, Brian J; Kalechstein, Ari D; De La Garza, Richard; Newton, Thomas F

    2011-03-30

    Abstinent methamphetamine (Meth) dependent individuals demonstrate poorer performance on tests sensitive to attention/information processing speed, learning and memory, and working memory when compared to non-Meth dependent individuals. The poorer performance on these tests may contribute to the morbidity associated with Meth-dependence. In light of this, we sought to determine the effects of acute, low-dose Meth administration on attention, working memory, and verbal learning and memory in 19 non-treatment seeking, Meth-dependent individuals. Participants were predominantly male (89%), Caucasian (63%), and cigarette smokers (63%). Following a four day, drug-free washout period, participants were given a single-blind intravenous infusion of saline, followed the next day by 30 mg of Meth. A battery of neurocognitive tasks was administered before and after each infusion, and performance on measures of accuracy and reaction time were compared between conditions. While acute Meth exposure did not affect test performance for the entire sample, participants who demonstrated relatively poor performance on these tests at baseline, identified using a median split on each test, showed significant improvement on measures of attention/information processing speed and working memory when administered Meth. Improved performance was seen on the following measures of working memory: choice reaction time task (p≤0.04), a 1-back task (p≤0.01), and a 2-back task (p≤0.04). In addition, those participants demonstrating high neurocognitive performance at baseline experienced similar or decreased performance following Meth exposure. These findings suggest that acute administration of Meth may temporarily improve Meth-associated neurocognitive performance in those individuals experiencing lower cognitive performance at baseline. As a result, stimulants may serve as a successful treatment for improving cognitive functioning in those Meth-dependent individuals experiencing neurocognitive impairment. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. Improved performance of the laser guide star adaptive optics system at Lick Observatory

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

    An, J R; Avicola, K; Bauman, B J

    1999-07-20

    Results of experiments with the laser guide star adaptive optics system on the 3-meter Shane telescope at Lick Observatory have demonstrated a factor of 4 performance improvement over previous results. Stellar images recorded at a wavelength of 2 {micro}m were corrected to over 40% of the theoretical diffraction-limited peak intensity. For the previous two years, this sodium-layer laser guide star system has corrected stellar images at this wavelength to {approx}10% of the theoretical peak intensity limit. After a campaign to improve the beam quality of the laser system, and to improve calibration accuracy and stability of the adaptive optics systemmore » using new techniques for phase retrieval and phase-shifting diffraction interferometry, the system performance has been substantially increased. The next step will be to use the Lick system for astronomical science observations, and to demonstrate this level of performance with the new system being installed on the 10-meter Keck II telescope.« less

  15. Managing Resources and Relations in Higher Education Institutions: A Framework for Understanding Performance Improvement

    ERIC Educational Resources Information Center

    Ho, Sophia Shi-Huei; Peng, Michael Yao-Ping

    2016-01-01

    Changes in social systems demonstrate that various structural disadvantages have jointly led to increasing competition among higher education institutions (HEIs) in many countries, especially Taiwan. Institutional administrators must recognize the need to understand how to improve performance and consistently outperform other institutions.…

  16. Case Study for the ARRA-funded GSHP Demonstration at University at Albany

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

    Liu, Xiaobing; Malhotra, Mini; Xiong, Zeyu

    High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This report highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects—a distributed GSHP system at a new 500-bed apartment-style student residence hall at the University at Albany. This case studymore » is based on the analysis of detailed design documents, measured performance data, published catalog data of heat pump equipment, and actual construction costs. Simulations with a calibrated computer model are performed for both the demonstrated GSHP system and a baseline heating, ventilation, and airconditioning (HVAC) system to determine the energy savings and other related benefits achieved by the GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, as well as the pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the demonstrated GSHP system compared with the baseline HVAC system. This case study also identifies opportunities for improving the operational efficiency of the demonstrated GSHP system.« less

  17. Improved high-dimensional prediction with Random Forests by the use of co-data.

    PubMed

    Te Beest, Dennis E; Mes, Steven W; Wilting, Saskia M; Brakenhoff, Ruud H; van de Wiel, Mark A

    2017-12-28

    Prediction in high dimensional settings is difficult due to the large number of variables relative to the sample size. We demonstrate how auxiliary 'co-data' can be used to improve the performance of a Random Forest in such a setting. Co-data are incorporated in the Random Forest by replacing the uniform sampling probabilities that are used to draw candidate variables by co-data moderated sampling probabilities. Co-data here are defined as any type information that is available on the variables of the primary data, but does not use its response labels. These moderated sampling probabilities are, inspired by empirical Bayes, learned from the data at hand. We demonstrate the co-data moderated Random Forest (CoRF) with two examples. In the first example we aim to predict the presence of a lymph node metastasis with gene expression data. We demonstrate how a set of external p-values, a gene signature, and the correlation between gene expression and DNA copy number can improve the predictive performance. In the second example we demonstrate how the prediction of cervical (pre-)cancer with methylation data can be improved by including the location of the probe relative to the known CpG islands, the number of CpG sites targeted by a probe, and a set of p-values from a related study. The proposed method is able to utilize auxiliary co-data to improve the performance of a Random Forest.

  18. Mindfulness training modifies subsystems of attention.

    PubMed

    Jha, Amism P; Krompinger, Jason; Baime, Michael J

    2007-06-01

    Mindfulness is defined as paying attention in the present moment. We investigate the hypothesis that mindfulness training may alter or enhance specific aspects of attention. We examined three functionally and neuroanatomically distinct but overlapping attentional subsystems: alerting, orienting, and conflict monitoring. Functioning of each subsystem was indexed by performance on the Attention Network Test. Two types of mindfulness training (MT) programs were examined, and behavioral testing was conducted on participants before (Time 1) and after (Time 2) training. One training group consisted of individuals naive to mindfulness techniques who participated in an 8-week mindfulness-based stress reduction (MBSR) course that emphasized the development of concentrative meditation skills. The other training group consisted of individuals experienced in concentrative meditation techniques who participated in a 1-month intensive mindfulness retreat. Performance of these groups was compared with that of control participants who were meditation naive and received no MT. At Time 1, the participants in the retreat group demonstrated improved conflict monitoring performance relative to those in the MBSR and control groups. At Time 2, the participants in the MBSR course demonstrated significantly improved orienting in comparison with the control and retreat participants. In contrast, the participants in the retreat group demonstrated altered performance on the alerting component, with improvements in exogenous stimulus detection in comparison with the control and MBSR participants. The groups did not differ in conflict monitoring performance at Time 2. These results suggest that mindfulness training may improve attention-related behavioral responses by enhancing functioning of specific subcomponents of attention. Whereas participation in the MBSR course improved the ability to endogenously orient attention, retreat participation appeared to allow for the development and emergence of receptive attentional skills, which improved exogenous alerting-related process.

  19. Develop feedback system for intelligent dynamic resource allocation to improve application performance.

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

    Gentile, Ann C.; Brandt, James M.; Tucker, Thomas

    2011-09-01

    This report provides documentation for the completion of the Sandia Level II milestone 'Develop feedback system for intelligent dynamic resource allocation to improve application performance'. This milestone demonstrates the use of a scalable data collection analysis and feedback system that enables insight into how an application is utilizing the hardware resources of a high performance computing (HPC) platform in a lightweight fashion. Further we demonstrate utilizing the same mechanisms used for transporting data for remote analysis and visualization to provide low latency run-time feedback to applications. The ultimate goal of this body of work is performance optimization in the facemore » of the ever increasing size and complexity of HPC systems.« less

  20. Neuromuscular training improves performance and lower-extremity biomechanics in female athletes.

    PubMed

    Myer, Gregory D; Ford, Kevin R; Palumbo, Joseph P; Hewett, Timothy E

    2005-02-01

    The purpose of this study was to examine the effects of a comprehensive neuromuscular training program on measures of performance and lower-extremity movement biomechanics in female athletes. The hypothesis was that significant improvements in measures of performance would be demonstrated concomitant with improved biomechanical measures related to anterior cruciate ligament injury risk. Forty-one female basketball, soccer, and volleyball players (age, 15.3 +/- 0.9 years; weight, 64.8 +/- 9.96 kg; height, 171.2 +/- 7.21 cm) underwent 6 weeks of training that included 4 main components (plyometric and movement, core strengthening and balance, resistance training, and speed training). Twelve age-, height-, and weight-matched controls underwent the same testing protocol twice 6 weeks apart. Trained athletes demonstrated increased predicted 1 repetition maximum squat (92%) and bench press (20%). Right and left single-leg hop distance increased 10.39 cm and 8.53 cm, respectively, and vertical jump also increased from 39.9 +/- 0.9 cm to 43.2 +/- 1.1 cm with training. Speed in a 9.1-m sprint improved from 1.80 +/- 0.02 seconds to 1.73 +/- 0.01 seconds. Pre- and posttest 3-dimensional motion analysis demonstrated increased knee flexion-extension range of motion during the landing phase of a vertical jump (right, 71.9 +/- 1.4 degrees to 76.9 +/- 1.4 degrees ; left, 71.3 +/- 1.5 degrees to 77.3 +/- 1.4 degrees ). Training decreased knee valgus (28%) and varus (38%) torques. Control subjects did not demonstrate significant alterations during the 6-week interval. The results of this study support the hypothesis that the combination of multiple-injury prevention-training components into a comprehensive program improves measures of performance and movement biomechanics.

  1. CF6 Jet Engine Performance Improvement Program: High Pressure Turbine Aerodynamic Performance Improvement

    NASA Technical Reports Server (NTRS)

    Fasching, W. A.

    1980-01-01

    The improved single shank high pressure turbine design was evaluated in component tests consisting of performance, heat transfer and mechanical tests, and in core engine tests. The instrumented core engine test verified the thermal, mechanical, and aeromechanical characteristics of the improved turbine design. An endurance test subjected the improved single shank turbine to 1000 simulated flight cycles, the equivalent of approximately 3000 hours of typical airline service. Initial back-to-back engine tests demonstrated an improvement in cruise sfc of 1.3% and a reduction in exhaust gas temperature of 10 C. An additional improvement of 0.3% in cruise sfc and 6 C in EGT is projected for long service engines.

  2. Relative benefits of stimulant therapy with OROS methylphenidate versus mixed amphetamine salts extended release in improving the driving performance of adolescent drivers with attention-deficit/hyperactivity disorder.

    PubMed

    Cox, Daniel J; Merkel, R Lawrence; Moore, Melissa; Thorndike, Frances; Muller, Carrie; Kovatchev, Boris

    2006-09-01

    Automobile accidents are the leading cause of death among adolescents, and collisions are 2 to 4 times more likely to occur among adolescents with attention-deficit/hyperactivity disorder. Studies have demonstrated that stimulants improve driving performance. This study compared 2 long-acting stimulant medications during daytime and evening driving evaluations. Adolescent drivers with attention-deficit/hyperactivity disorder were compared on a driving simulator after taking 72 mg of OROS methylphenidate, 30 mg of mixed amphetamine salts extended release, or placebo in a randomized, double-blind, placebo-controlled, crossover study design. During laboratory testing, adolescents drove a driving simulator at 5:00 pm, 8:00 pm, and 11:00 pm. Driving performance was rated by adolescents and investigators. The study included 35 adolescent drivers with attention-deficit/hyperactivity disorder (19 boys/16 girls). The mean age was 17.8 years. The overall Impaired Driving Score demonstrated that OROS methylphenidate led to better driving performance compared with placebo and mixed amphetamine salts extended release, whereas mixed amphetamine salts extended release demonstrated no statistical improvement over placebo. Specifically, relative to placebo, OROS methylphenidate resulted in less time driving off the road, fewer instances of speeding, less erratic speed control, more time executing left turns, and less inappropriate use of brakes. OROS methylphenidate and mixed amphetamine salts extended release worked equally well for male and female adolescents and equally as well with teenagers who have combined and inattentive subtypes of attention-deficit/hyperactivity disorder. This study validates the use of stimulants to improve driving performance in adolescents with attention-deficit/hyperactivity disorder. In the study, OROS methylphenidate promoted significantly improved driving performance compared with placebo and mixed amphetamine salts extended release.

  3. Lithium Batteries and Supercapacitors Capable of Operating at Low Temperatures for Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Smart, M. C.; Ratnakumar, B. V.; West, W. C.; Brandon, E. J.

    2012-01-01

    Demonstrated improved performance with wide operating temperature electrolytes containing ester co - solvents (i.e., methyl propionate and ethyl butyrate) in a number of prototype cells: center dot Successfully scaled up low temperature technology to 12 Ah size prismatic Li - ion cells (Quallion, LCC), and demonstrated good performance down to - 60 o C. center dot Demonstrated wide operating temperature range performance ( - 60 o to +60 o C) in A123 Systems LiFePO 4 - based lithium - ion cells containing methyl butyrate - based low temperature electrolytes. These systems were also demonstrated to have excellent cycle life performance at ambient temperatures, as well as the ability to be cycled up to high temperatures.

  4. ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA. U.S. EPA DEMONSTRATION PROJECT AT SOUTH TRUCKEE MEADOWS GENERAL IMPROVEMENT DISTRICT (STMIG), NV. INTERIM EVALUATION REPORT

    EPA Science Inventory

    This report documents the activities performed during and the results obtained from the first 32 weeks of operation of an arsenic and antimony removal technology currently being demonstrated at the South Truckee Meadows General Improvement District (STMGID) in Washoe County, NV. ...

  5. JT8D-15/17 High Pressure Turbine Root Discharged Blade Performance Improvement. [engine design

    NASA Technical Reports Server (NTRS)

    Janus, A. S.

    1981-01-01

    The JT8D high pressure turbine blade and seal were modified, using a more efficient blade cooling system, improved airfoil aerodynamics, more effective control of secondary flows, and improved blade tip sealing. Engine testing was conducted to determine the effect of these improvements on performance. The modified turbine package demonstrated significant thrust specific fuel consumption and exhaust gas temperature improvements in sea level and altitude engine tests. Inspection of the improved blade and seal hardware after testing revealed no unusual wear or degradation.

  6. Uncertain behaviours of integrated circuits improve computational performance.

    PubMed

    Yoshimura, Chihiro; Yamaoka, Masanao; Hayashi, Masato; Okuyama, Takuya; Aoki, Hidetaka; Kawarabayashi, Ken-ichi; Mizuno, Hiroyuki

    2015-11-20

    Improvements to the performance of conventional computers have mainly been achieved through semiconductor scaling; however, scaling is reaching its limitations. Natural phenomena, such as quantum superposition and stochastic resonance, have been introduced into new computing paradigms to improve performance beyond these limitations. Here, we explain that the uncertain behaviours of devices due to semiconductor scaling can improve the performance of computers. We prototyped an integrated circuit by performing a ground-state search of the Ising model. The bit errors of memory cell devices holding the current state of search occur probabilistically by inserting fluctuations into dynamic device characteristics, which will be actualised in the future to the chip. As a result, we observed more improvements in solution accuracy than that without fluctuations. Although the uncertain behaviours of devices had been intended to be eliminated in conventional devices, we demonstrate that uncertain behaviours has become the key to improving computational performance.

  7. Applying Neurological Learning Research to an Online Undergraduate Science Laboratory Course

    ERIC Educational Resources Information Center

    Byrd, Dana; Byrd, Gene

    2013-01-01

    Neurological research has demonstrated that pre-test verbal preparation improves performance. The well-tested Tower of London puzzle can assess cognitive skills of a wide age range of participants. Preschoolers who talked to themselves about future puzzle moves had greatly improved Tower of London performance over those without such preparation.…

  8. Active-Learning Methods To Improve Student Performance and Scientific Interest in a Large Introductory Oceanography Course.

    ERIC Educational Resources Information Center

    Yuretich, Richard F.; Khan, Samia A.; Leckie, R. Mark; Clement, John J.

    2001-01-01

    Transfers the environment of a large enrollment oceanography course by modifying lectures to include cooperative learning via interactive in-class exercises and directed discussion. Results of student surveys, course evaluations, and exam performance demonstrate that learning of the subject under these conditions has improved. (Author/SAH)

  9. The Ethics of PI: A Polemical Overview.

    ERIC Educational Resources Information Center

    Stewart, Jim

    2003-01-01

    Suggests that Human Resource Development (HRD) is in and of itself an ethical endeavor. Starts with a brief discussion about human performance improvement, next explores the issue of ethics, and then brings the two together to demonstrate the truth and validity of the argument that performance improvement (PI) is an ethical endeavor. (AEF)

  10. Engineering MoSx/Ti/InP Hybrid Photocathode for Improved Solar Hydrogen Production

    NASA Astrophysics Data System (ADS)

    Li, Qiang; Zheng, Maojun; Zhong, Miao; Ma, Liguo; Wang, Faze; Ma, Li; Shen, Wenzhong

    2016-07-01

    Due to its direct band gap of ~1.35 eV, appropriate energy band-edge positions, and low surface-recombination velocity, p-type InP has attracted considerable attention as a promising photocathode material for solar hydrogen generation. However, challenges remain with p-type InP for achieving high and stable photoelectrochemical (PEC) performances. Here, we demonstrate that surface modifications of InP photocathodes with Ti thin layers and amorphous MoSx nanoparticles can remarkably improve their PEC performances. A high photocurrent density with an improved PEC onset potential is obtained. Electrochemical impedance analyses reveal that the largely improved PEC performance of MoSx/Ti/InP is attributed to the reduced charge-transfer resistance and the increased band bending at the MoSx/Ti/InP/electrolyte interface. In addition, the MoSx/Ti/InP photocathodes function stably for PEC water reduction under continuous light illumination over 2 h. Our study demonstrates an effective approach to develop high-PEC-performance InP photocathodes towards stable solar hydrogen production.

  11. Engineering MoSx/Ti/InP Hybrid Photocathode for Improved Solar Hydrogen Production

    PubMed Central

    Li, Qiang; Zheng, Maojun; Zhong, Miao; Ma, Liguo; Wang, Faze; Ma, Li; Shen, Wenzhong

    2016-01-01

    Due to its direct band gap of ~1.35 eV, appropriate energy band-edge positions, and low surface-recombination velocity, p-type InP has attracted considerable attention as a promising photocathode material for solar hydrogen generation. However, challenges remain with p-type InP for achieving high and stable photoelectrochemical (PEC) performances. Here, we demonstrate that surface modifications of InP photocathodes with Ti thin layers and amorphous MoSx nanoparticles can remarkably improve their PEC performances. A high photocurrent density with an improved PEC onset potential is obtained. Electrochemical impedance analyses reveal that the largely improved PEC performance of MoSx/Ti/InP is attributed to the reduced charge-transfer resistance and the increased band bending at the MoSx/Ti/InP/electrolyte interface. In addition, the MoSx/Ti/InP photocathodes function stably for PEC water reduction under continuous light illumination over 2 h. Our study demonstrates an effective approach to develop high-PEC-performance InP photocathodes towards stable solar hydrogen production. PMID:27431993

  12. Engineering MoSx/Ti/InP Hybrid Photocathode for Improved Solar Hydrogen Production.

    PubMed

    Li, Qiang; Zheng, Maojun; Zhong, Miao; Ma, Liguo; Wang, Faze; Ma, Li; Shen, Wenzhong

    2016-07-19

    Due to its direct band gap of ~1.35 eV, appropriate energy band-edge positions, and low surface-recombination velocity, p-type InP has attracted considerable attention as a promising photocathode material for solar hydrogen generation. However, challenges remain with p-type InP for achieving high and stable photoelectrochemical (PEC) performances. Here, we demonstrate that surface modifications of InP photocathodes with Ti thin layers and amorphous MoSx nanoparticles can remarkably improve their PEC performances. A high photocurrent density with an improved PEC onset potential is obtained. Electrochemical impedance analyses reveal that the largely improved PEC performance of MoSx/Ti/InP is attributed to the reduced charge-transfer resistance and the increased band bending at the MoSx/Ti/InP/electrolyte interface. In addition, the MoSx/Ti/InP photocathodes function stably for PEC water reduction under continuous light illumination over 2 h. Our study demonstrates an effective approach to develop high-PEC-performance InP photocathodes towards stable solar hydrogen production.

  13. Learning-based image preprocessing for robust computer-aided detection

    NASA Astrophysics Data System (ADS)

    Raghupathi, Laks; Devarakota, Pandu R.; Wolf, Matthias

    2013-03-01

    Recent studies have shown that low dose computed tomography (LDCT) can be an effective screening tool to reduce lung cancer mortality. Computer-aided detection (CAD) would be a beneficial second reader for radiologists in such cases. Studies demonstrate that while iterative reconstructions (IR) improve LDCT diagnostic quality, it however degrades CAD performance significantly (increased false positives) when applied directly. For improving CAD performance, solutions such as retraining with newer data or applying a standard preprocessing technique may not be suffice due to high prevalence of CT scanners and non-uniform acquisition protocols. Here, we present a learning-based framework that can adaptively transform a wide variety of input data to boost an existing CAD performance. This not only enhances their robustness but also their applicability in clinical workflows. Our solution consists of applying a suitable pre-processing filter automatically on the given image based on its characteristics. This requires the preparation of ground truth (GT) of choosing an appropriate filter resulting in improved CAD performance. Accordingly, we propose an efficient consolidation process with a novel metric. Using key anatomical landmarks, we then derive consistent feature descriptors for the classification scheme that then uses a priority mechanism to automatically choose an optimal preprocessing filter. We demonstrate CAD prototype∗ performance improvement using hospital-scale datasets acquired from North America, Europe and Asia. Though we demonstrated our results for a lung nodule CAD, this scheme is straightforward to extend to other post-processing tools dedicated to other organs and modalities.

  14. Amphetamine margin in sports. [Effects on performance of highly trained athletes

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

    Laties, V.G.; Weiss, B.

    The amphetamines can enhance athletic performance. That much seems clear from the literature, some of which is reviewed here. Increases in endurance have been demonstrated in both man and rat. Smith and Beecher, 20 years ago, showed improvement of running, swimming, and weight throwing in highly trained athletes. Laboratory analogues of such performance have also been used and similar enhancement demonstrated. The amount of change induced by the amphetamines is usually small, of the order of a few percent. Nevertheless, since a fraction of a percent improvement can make the difference between fame and oblivion, the margin conferred by thesemore » drugs can be quite important.« less

  15. LPV Controller Interpolation for Improved Gain-Scheduling Control Performance

    NASA Technical Reports Server (NTRS)

    Wu, Fen; Kim, SungWan

    2002-01-01

    In this paper, a new gain-scheduling control design approach is proposed by combining LPV (linear parameter-varying) control theory with interpolation techniques. The improvement of gain-scheduled controllers can be achieved from local synthesis of Lyapunov functions and continuous construction of a global Lyapunov function by interpolation. It has been shown that this combined LPV control design scheme is capable of improving closed-loop performance derived from local performance improvement. The gain of the LPV controller will also change continuously across parameter space. The advantages of the newly proposed LPV control is demonstrated through a detailed AMB controller design example.

  16. Simulation-Based Cryosurgery Training: Variable Insertion-Depth Planning in Prostate Cryosurgery

    PubMed Central

    Sehrawat, Anjali; Keelan, Robert; Shimada, Kenji; Wilfong, Dona M.; McCormick, James T.; Rabin, Yoed

    2015-01-01

    A proof-of-concept for an advanced-level computerized training tool for cryosurgery is demonstrated, based on three-dimensional cryosurgery simulations and a variable insertion-depth strategy for cryoprobes. The objective for system development is twofold: to identify a cryoprobe layout in order to best-match a planning isotherm with the target region shape, and to verify that cryoprobe placement does not violate accepted geometric constraints. System validation has been performed by collecting training data from 17 surgical residents, having no prior experience or advanced knowledge of cryosurgery. This advanced-level study includes an improved training-session design, in order to enhance knowledge dissemination and elevate participant motivation to excel. In terms of match between a planning isotherm and the target region shape, results of this demonstrate trainee performance improvement from 4.4% in a pretest to 44.4% in a posttest over a course of 50 minutes of training. In terms of combined performance, including the above geometrical match and constraints on cryoprobe placement, this study demonstrates trainee performance improvement from 2.2% in the pretest to 31.1% in the posttest. Given the relatively short training session and the lack of prior knowledge, these improvements are significant and encouraging. These results are of particular significance, as they have been obtained from a surgical resident population, which are exposed to the typical stress and constraints in advanced surgical education. PMID:26546576

  17. Fiber composite fan blade impact improvement program

    NASA Technical Reports Server (NTRS)

    Oller, T. L.

    1976-01-01

    The results of a 20-month program, designed to investigate parameters which effect the foreign object damage resulting from ingestion of birds into fan blades are described. Work performed on this program included the design, fabrication, and impact testing of QCSEE fan blades to demonstrate improvement in resistance relative to existing blades and also the design and demonstration of a pin root attachment concept.

  18. Positioning performance improvements with European multiple-frequency satellite navigation - Galileo

    NASA Astrophysics Data System (ADS)

    Ji, Shengyue

    2008-10-01

    The rapid development of Global Positioning System has demonstrated the advantages of satellite based navigation systems. In near future, there will be a number of Global Navigation Satellite System (GNSS) available, i.e. modernized GPS, Galileo, restored GLONASS, BeiDou and many other regional GNSS augmentation systems. Undoubtedly, the new GNSS systems will significantly improve navigation performance over current GPS, with a better satellite coverage and multiple satellite signal bands. In this dissertation, the positioning performance improvement of new GNSS has been investigated based on both theoretical analysis and numerical study. First of all, the navigation performance of new GNSS systems has been analyzed, particularly for urban applications. The study has demonstrated that Receiver Autonomous Integrity Monitoring (RAIM) performance can be significantly improved with multiple satellite constellations, although the position accuracy improvement is limited. Based on a three-dimensional urban building model in Hong Kong streets, it is found that positioning availability is still very low in high-rising urban areas, even with three GNSS systems. On the other hand, the discontinuity of navigation solutions is significantly reduced with the combined constellations. Therefore, it is possible to use cheap DR systems to bridge the gaps of GNSS positioning, with high accuracy. Secondly, the ambiguity resolution performance has been investigated with Galileo multiple frequency band signals. The ambiguity resolution performance of three different algorithms is compared, including CAR, ILS and improved CAR methods (a new method proposed in this study). For short baselines, with four frequency Galileo data, it is highly possible to achieve reliable single epoch ambiguity resolution, when the carrier phase noise level is reasonably low (i.e. less than 6mm). For long baselines (up to 800 km), the integer ambiguity can be determined within 1 min on average. Ambiguity validation is crucial for any ambiguity resolution algorithm using searching method. This study has proposed to use both Ellipsoidal Integer Aperture (EIA) estimator and R-ratio test for ambiguity validation. Using real GPS data and simulated Galileo data, it has been demonstrated that the new method performs better than the use of EIA or the R-ratio test alone, with much less ambiguity mis-fixed rate.

  19. Knowledge representation into Ada parallel processing

    NASA Technical Reports Server (NTRS)

    Masotto, Tom; Babikyan, Carol; Harper, Richard

    1990-01-01

    The Knowledge Representation into Ada Parallel Processing project is a joint NASA and Air Force funded project to demonstrate the execution of intelligent systems in Ada on the Charles Stark Draper Laboratory fault-tolerant parallel processor (FTPP). Two applications were demonstrated - a portion of the adaptive tactical navigator and a real time controller. Both systems are implemented as Activation Framework Objects on the Activation Framework intelligent scheduling mechanism developed by Worcester Polytechnic Institute. The implementations, results of performance analyses showing speedup due to parallelism and initial efficiency improvements are detailed and further areas for performance improvements are suggested.

  20. Case studies for GSHP demonstration projects in the US

    DOE PAGES

    Liu, Xiaobing; Malhotra, Mini; Im, Piljae

    2015-07-01

    Under the American Recovery and Reinvestment Act , twenty-six ground source heat pump (GSHP) projects were competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This article gives an overview of the case studies for six of the systems. These case studies evaluated efficiencies, energy savings, and costs of the demonstrated systems. In addition, it was found that more energy savings could be achieved if controls of GSHP system are improved.

  1. Creative Writing and Learning in a Conceptual Astrophysics Course

    NASA Astrophysics Data System (ADS)

    Berenson, R.

    2012-08-01

    Creative writing assignments in a conceptual astrophysics course for liberal arts students can reduce student anxiety. This study demonstrates that such assignments also can aid learning as demonstrated by significantly improved performance on exams.

  2. The CF6 jet engine performance improvement: New front mount

    NASA Technical Reports Server (NTRS)

    Fasching, W. A.

    1979-01-01

    The New Front Mount was evaluated in component tests including stress, deflection/distortion and fatigue tests. The test results demonstrated a performance improvement of 0.1% in cruise sfc, 16% in compressor stall margin and 10% in compressor stator angle margin. The New Front Mount hardware successfully completed 35,000 simulated flight cycles endurance testing.

  3. An Efficient Method for the Retrieval of Objects by Topological Relations in Spatial Database Systems.

    ERIC Educational Resources Information Center

    Lin, P. L.; Tan, W. H.

    2003-01-01

    Presents a new method to improve the performance of query processing in a spatial database. Experiments demonstrated that performance of database systems can be improved because both the number of objects accessed and number of objects requiring detailed inspection are much less than those in the previous approach. (AEF)

  4. Short-term music training enhances verbal intelligence and executive function.

    PubMed

    Moreno, Sylvain; Bialystok, Ellen; Barac, Raluca; Schellenberg, E Glenn; Cepeda, Nicholas J; Chau, Tom

    2011-11-01

    Researchers have designed training methods that can be used to improve mental health and to test the efficacy of education programs. However, few studies have demonstrated broad transfer from such training to performance on untrained cognitive activities. Here we report the effects of two interactive computerized training programs developed for preschool children: one for music and one for visual art. After only 20 days of training, only children in the music group exhibited enhanced performance on a measure of verbal intelligence, with 90% of the sample showing this improvement. These improvements in verbal intelligence were positively correlated with changes in functional brain plasticity during an executive-function task. Our findings demonstrate that transfer of a high-level cognitive skill is possible in early childhood.

  5. Test and evaluation of the HIDEC engine uptrim algorithm

    NASA Technical Reports Server (NTRS)

    Ray, R. J.; Myers, L. P.

    1986-01-01

    The highly integrated digital electronic control (HIDEC) program will demonstrate and evaluate the improvements in performance and mission effectiveness that result from integrated engine-airframe control systems. Performance improvements will result from an adaptive engine stall margin mode, a highly integrated mode that uses the airplane flight conditions and the resulting inlet distortion to continuously compute engine stall margin. When there is excessive stall margin, the engine is uptrimmed for more thrust by increasing engine pressure ratio (EPR). The EPR uptrim logic has been evaluated and implemented into computer simulations. Thrust improvements over 10 percent are predicted for subsonic flight conditions. The EPR uptrim was successfully demonstrated during engine ground tests. Test results verify model predictions at the conditions tested.

  6. Performance improvement with patient service partners.

    PubMed

    Burns, J P

    1998-01-01

    Once the decision is made to use a patient-focused care delivery system, a variety of methods can be used to successfully design the model. The author describes the process used by a multilevel, multidisciplinary team at a community hospital to design and implement a Service Partner role that would meet and exceed customer expectations. Demonstrated performance improvements included increased patient satisfaction, productive labor dollar savings, and improvements in the work environment for staff members.

  7. Models for Improving the Delivery of Services to: Gifted Students in the Areas of Visual and Performing Arts. Research & Demonstration Series in Gifted Education.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Special Education.

    This report describes three model demonstration projects in Ohio school districts which focused on strategies for identifying students gifted in visual and performing arts and delivering hands-on arts education and appreciation experiences. Presented for each program is information on: identifying characteristics (district, location, school…

  8. Subsurface Thermal Energy Storage for Improved Heating and Air Conditioning Efficiency

    DTIC Science & Technology

    2016-11-21

    This project involved a field demonstration of subsurface thermal energy storage for improving the geothermal heat pump air conditioning efficiency... geothermal heat pump systems, undesirable heating of the ground may occur. This demonstration was performed at the MCAS, Beaufort, SC, where several...buildings with geothermal heat pump systems were exhibiting excessively high ground loop temperatures. These buildings were retrofitted with dry fluid

  9. Progress in the utilization of an oxide-dispersion-strengthened alloy for small engine turbine blades

    NASA Technical Reports Server (NTRS)

    Beatty, T. G.; Millan, P. P.

    1984-01-01

    The conventional means of improving gas turbine engine performance typically involves increasing the turbine inlet temperature; however, at these higher operational temperatures the high pressure turbine blades require air-cooling to maintain durability. Air-cooling imposes design, material, and economic constraints not only on the turbine blades but also on engine performance. The use of uncooled turbine blades at increased operating temperatures can offer significantly improved performance in small gas turbine engines. A program to demonstrate uncooled MA6000 high pressure turbine blades in a GTEC TFE731 turbofan engine is being conducted. The project goals include demonstration of the advantages of using uncooled MA6000 turbine blades as compared with cast directionally solidified MAR-M 247 blades.

  10. Exponential H ∞ Synchronization of Chaotic Cryptosystems Using an Improved Genetic Algorithm

    PubMed Central

    Hsiao, Feng-Hsiag

    2015-01-01

    This paper presents a systematic design methodology for neural-network- (NN-) based secure communications in multiple time-delay chaotic (MTDC) systems with optimal H ∞ performance and cryptography. On the basis of the Improved Genetic Algorithm (IGA), which is demonstrated to have better performance than that of a traditional GA, a model-based fuzzy controller is then synthesized to stabilize the MTDC systems. A fuzzy controller is synthesized to not only realize the exponential synchronization, but also achieve optimal H ∞ performance by minimizing the disturbance attenuation level. Furthermore, the error of the recovered message is stated by using the n-shift cipher and key. Finally, a numerical example with simulations is given to demonstrate the effectiveness of our approach. PMID:26366432

  11. Decline in physical performance among women with a recent transient ischemic attack or ischemic stroke: opportunities for functional preservation a report of the Women's Estrogen Stroke Trial.

    PubMed

    Kernan, Walter N; Viscoli, Catherine M; Brass, Lawrence M; Gill, Thomas M; Sarrel, Philip M; Horwitz, Ralph I

    2005-03-01

    Physical performance for walking, reaching, turning, and other common tasks is a major determinant of functional independence after stroke. Current strategies to preserve physical performance focus on prevention of recurrent stroke. Loss of physical performance, however, may occur in the absence of recurrence. To examine this possibility, we measured change in physical performance, independent of subsequent stroke, among women with a recent ischemic stroke or transient ischemic attack (TIA). Among 664 postmenopausal women who participated in a clinical trial of estrogen therapy after stroke or TIA, we administered the Physical Performance Test (PPT) at baseline (mean 58 days from the cerebrovascular event) and annually. Women who died or had a stroke during follow-up were censored. Decline or improvement in physical performance was defined as a change in the PPT score from baseline of at least 3 points. Sustained decline or improvement was defined as 2 consecutive years during which the score had declined or improved, respectively, relative to the baseline score. With each year of follow-up, a smaller proportion of the cohort demonstrated improvement (16% in year 1, 6% in year 5) and a larger proportion demonstrated decline (15% in year 1, 35% in year 5). In an analysis restricted to 259 women with 3 years of follow-up, 46 (18%) experienced a nonsustained decline in physical performance, and 39 (15%) experienced a sustained decline. Decline in physical performance is common after an ischemic stroke or TIA even in the absence of a recurrent neurological event. Our findings suggest that specific interventions to maintain and improve physical performance may be important for reducing long-term disability.

  12. Simulator-Based Angiography and Endovascular Neurosurgery Curriculum: A Longitudinal Evaluation of Performance Following Simulator-Based Angiography Training.

    PubMed

    Pannell, J Scott; Santiago-Dieppa, David R; Wali, Arvin R; Hirshman, Brian R; Steinberg, Jeffrey A; Cheung, Vincent J; Oveisi, David; Hallstrom, Jon; Khalessi, Alexander A

    2016-08-29

    This study establishes performance metrics for angiography and neuroendovascular surgery procedures based on longitudinal improvement in individual trainees with differing levels of training and experience. Over the course of 30 days, five trainees performed 10 diagnostic angiograms, coiled 10 carotid terminus aneurysms in the setting of subarachnoid hemorrhage, and performed 10 left middle cerebral artery embolectomies on a Simbionix Angio Mentor™ simulator. All procedures were nonconsecutive. Total procedure time, fluoroscopy time, contrast dose, heart rate, blood pressures, medications administered, packing densities, the number of coils used, and the number of stent-retriever passes were recorded. Image quality was rated, and the absolute value of technically unsafe events was recorded. The trainees' device selection, macrovascular access, microvascular access, clinical management, and the overall performance of the trainee was rated during each procedure based on a traditional Likert scale score of 1=fail, 2=poor, 3=satisfactory, 4=good, and 5=excellent. These ordinal values correspond with published assessment scales on surgical technique. After performing five diagnostic angiograms and five embolectomies, all participants demonstrated marked decreases in procedure time, fluoroscopy doses, contrast doses, and adverse technical events; marked improvements in image quality, device selection, access scores, and overall technical performance were additionally observed (p < 0.05). Similarly, trainees demonstrated marked improvement in technical performance and clinical management after five coiling procedures (p < 0.05). However, trainees with less prior experience deploying coils continued to experience intra-procedural ruptures up to the eighth embolization procedure; this observation likely corresponded with less tactile procedural experience to an exertion of greater force than appropriate for coil placement. Trainees across all levels of training and prior experience demonstrated a significant performance improvement after completion of our simulator curriculum consisting of five diagnostic angiograms, five embolectomy cases, and 10 aneurysm coil embolizations.

  13. Comparison of active-learning strategies for motivational interviewing skills, knowledge, and confidence in first-year pharmacy students.

    PubMed

    Lupu, Ana M; Stewart, Autumn L; O'Neil, Christine

    2012-03-12

    To compare 3 strategies for pharmacy student learning of motivational interviewing skills, knowledge of motivational interviewing principles, and confidence in and attitudes toward their application. Following a motivational interviewing lecture, first-year students were randomized to perform practice activities (written dialogue, peer role-play, or mock-patient counseling activities). Motivational interviewing skills, knowledge, confidence, and attitudes were measured. All students demonstrated improvement in skills, knowledge, and confidence. Students in the mock-patient counseling group demonstrated significantly better motivational interviewing skills during practice and trended toward higher scores on the summative evaluation. They also demonstrated a significant improvement in knowledge compared with that of the written dialogue group during practice. Feedback at the end was generally positive, with students expressing recognition for the value of motivational interviewing. Students demonstrated their best performance of motivational interviewing during assessments using interactions with mock or standardized patients.

  14. A Bayesian method for using simulator data to enhance human error probabilities assigned by existing HRA methods

    DOE PAGES

    Groth, Katrina M.; Smith, Curtis L.; Swiler, Laura P.

    2014-04-05

    In the past several years, several international agencies have begun to collect data on human performance in nuclear power plant simulators [1]. This data provides a valuable opportunity to improve human reliability analysis (HRA), but there improvements will not be realized without implementation of Bayesian methods. Bayesian methods are widely used in to incorporate sparse data into models in many parts of probabilistic risk assessment (PRA), but Bayesian methods have not been adopted by the HRA community. In this article, we provide a Bayesian methodology to formally use simulator data to refine the human error probabilities (HEPs) assigned by existingmore » HRA methods. We demonstrate the methodology with a case study, wherein we use simulator data from the Halden Reactor Project to update the probability assignments from the SPAR-H method. The case study demonstrates the ability to use performance data, even sparse data, to improve existing HRA methods. Furthermore, this paper also serves as a demonstration of the value of Bayesian methods to improve the technical basis of HRA.« less

  15. Hearing on H.R. 3347, a National Demonstration Program for Educational Performance Agreements for School Restructuring. Hearing before the Subcommittee on Elementary, Secondary, and Vocational Education of the Committee on Education and Labor. House of Representatives, One Hundred First Congress, First Session (November 16, 1989).

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Committee on Education and Labor.

    Statements, prepared statements, letters, and supplemental materials are included in this hearing report on legislation to enact a national educational demonstration agreement for school restructuring. The goal of demonstration programs is to improve student performance at the local level with fewer federal state and local restrictions,…

  16. Improving Objective Measures of Mobility.

    ERIC Educational Resources Information Center

    Dodds, Allan G.; And Others

    1983-01-01

    The article examines shortcomings in existing objective measures of mobility for blind persons in the light of evaluative experiences and demonstrates improvements in reliability, together with a new technique for tracking pavement position. It refutes the idea that it is not possible to measure improvement in performance objectively. (Author/CL)

  17. Improving a Bimanual Motor Skill Through Unimanual Training

    PubMed Central

    Hayashi, Takuji; Nozaki, Daichi

    2016-01-01

    When we learn a bimanual motor skill (e.g., rowing a boat), we often break it down into unimanual practices (e.g., a rowing drill with the left or right arm). Such unimanual practice is thought to be useful for learning bimanual motor skills efficiently because the learner can concentrate on learning to perform a simpler component. However, it is not so straightforward to assume that unimanual training (UT) improves bimanual performance. We have previously demonstrated that motor memories for reaching movements consist of three different parts: unimanual-specific, bimanual-specific, and overlapping parts. According to this scheme, UT appears to be less effective, as its training effect is only partially transferred to the same limb for bimanual movement. In the present study, counter-intuitively, we demonstrate that, even after the bimanual skill is almost fully learned by means of bimanual training (BT), additional UT could further improve bimanual skill. We hypothesized that this effect occurs because UT increases the memory content in the overlapping part, which might contribute to an increase in the memory for bimanual movement. To test this hypothesis, we examined whether the UT performed after sufficient BT could improve the bimanual performance. Participants practiced performing bimanual reaching movements (BM) in the presence of a novel force-field imposed only on their left arm. As an index for the motor performance, we used the error-clamp method (i.e., after-effect of the left arm) to evaluate the force output to compensate for the force-field during the reaching movement. After sufficient BT, the training effect reached a plateau. However, UT performed subsequently improved the bimanual performance significantly. In contrast, when the same amount of BT was continued, the bimanual performance remained unchanged, highlighting the beneficial effect of UT on bimanual performance. Considering memory structure, we also expected that BT could improve unimanual performance, which was confirmed by another experiment. These results provide a new interpretation of why UT was useful for improving a bimanual skill, and propose a practical strategy for enhancing performance by performing training in various contexts. PMID:27471452

  18. High Efficiency Low Cost CO2 Compression Using Supersonic Shock Wave Technology

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

    Williams, J; Aarnio, M; Grosvenor, A

    2010-12-31

    Development and testing results from a supersonic compressor are presented. The compressor achieved record pressure ratio for a fully-supersonic stage and successfully demonstrated the technology potential. Several tasks were performed in compliance with the DOE award objectives. A high-pressure ratio compressor was retrofitted to improve rotordynamics behavior and successfully tested. An outside review panel confirmed test results and design approach. A computational fluid dynamics code used to analyze the Ramgen supersonic flowpath was extensively and successfully modified to improve use on high-performance computing platforms. A comprehensive R&D implementation plan was developed and used to lay the groundwork for a futuremore » full-scale compressor demonstration. Conceptual design for a CO2 demonstration compressor was developed and reviewed.« less

  19. Novel Power Electronics Three-Dimensional Heat Exchanger: Preprint

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

    Bennion, K.; Cousineau, J.; Lustbader, J.

    2014-08-01

    Electric drive systems for vehicle propulsion enable technologies critical to meeting challenges for energy, environmental, and economic security. Enabling cost-effective electric drive systems requires reductions in inverter power semiconductor area. As critical components of the electric drive system are made smaller, heat removal becomes an increasing challenge. In this paper, we demonstrate an integrated approach to the design of thermal management systems for power semiconductors that matches the passive thermal resistance of the packaging with the active convective cooling performance of the heat exchanger. The heat exchanger concept builds on existing semiconductor thermal management improvements described in literature and patents,more » which include improved bonded interface materials, direct cooling of the semiconductor packages, and double-sided cooling. The key difference in the described concept is the achievement of high heat transfer performance with less aggressive cooling techniques by optimizing the passive and active heat transfer paths. An extruded aluminum design was selected because of its lower tooling cost, higher performance, and scalability in comparison to cast aluminum. Results demonstrated a heat flux improvement of a factor of two, and a package heat density improvement over 30%, which achieved the thermal performance targets.« less

  20. Performance of Improved High-Order Filter Schemes for Turbulent Flows with Shocks

    NASA Technical Reports Server (NTRS)

    Kotov, Dmitry Vladimirovich; Yee, Helen M C.

    2013-01-01

    The performance of the filter scheme with improved dissipation control ? has been demonstrated for different flow types. The scheme with local ? is shown to obtain more accurate results than its counterparts with global or constant ?. At the same time no additional tuning is needed to achieve high accuracy of the method when using the local ? technique. However, further improvement of the method might be needed for even more complex and/or extreme flows.

  1. Digital electronic engine control history

    NASA Technical Reports Server (NTRS)

    Putnam, T. W.

    1984-01-01

    Full authority digital electronic engine controls (DEECs) were studied, developed, and ground tested because of projected benefits in operability, improved performance, reduced maintenance, improved reliability, and lower life cycle costs. The issues of operability and improved performance, however, are assessed in a flight test program. The DEEC on a F100 engine in an F-15 aircraft was demonstrated and evaluated. The events leading to the flight test program are chronicled and important management and technical results are identified.

  2. Development of optimized, graded-permeability axial groove heat pipes

    NASA Technical Reports Server (NTRS)

    Kapolnek, Michael R.; Holmes, H. Rolland

    1988-01-01

    Heat pipe performance can usually be improved by uniformly varying or grading wick permeability from end to end. A unique and cost effective method for grading the permeability of an axial groove heat pipe is described - selective chemical etching of the pipe casing. This method was developed and demonstrated on a proof-of-concept test article. The process improved the test article's performance by 50 percent. Further improvement is possible through the use of optimally etched grooves.

  3. CF6 jet engine performance improvement: New fan

    NASA Technical Reports Server (NTRS)

    Fasching, W. A.

    1980-01-01

    As part of the NASA sponsored engine component improvement program, and fan package was developed to reduce fuel consumption in current CF6 turbofan aircraft engine. The new fan package consist of an improved fan blade, reduced fan tip clearance due to a fan case stiffener, and a smooth fan casing tip shroud. CF6 engine performance and acoustic tests demonstrated the predicted 1.8% improvement in cruise sfc without an increase in engine noise. Power management thrust/fan speed characteristics were defined. Mechanical and structural integrity was demonstrated in model fan rotor photoelastic stress tests, full-size fan blade bench fatigue tests, and CF6 engine bird ingestion, crosswind, and cyclic endurance tests. The fan was certified in the CF6-500c2/E2 engines and is in commerical service on the Boeing 747-200, Douglas DC-10-30, and Atrbus industrie A300B aircraft.

  4. Test and evaluation of the HIDEC engine uptrim algorithm. [Highly Integrated Digital Electronic Control for aircraft

    NASA Technical Reports Server (NTRS)

    Ray, R. J.; Myers, L. P.

    1986-01-01

    The highly integrated digital electronic control (HIDEC) program will demonstrate and evaluate the improvements in performance and mission effectiveness that result from integrated engine-airframe control systems. Performance improvements will result from an adaptive engine stall margin mode, a highly integrated mode that uses the airplane flight conditions and the resulting inlet distortion to continuously compute engine stall margin. When there is excessive stall margin, the engine is uptrimmed for more thrust by increasing engine pressure ratio (EPR). The EPR uptrim logic has been evaluated and implemente into computer simulations. Thrust improvements over 10 percent are predicted for subsonic flight conditions. The EPR uptrim was successfully demonstrated during engine ground tests. Test results verify model predictions at the conditions tested.

  5. Amphetamine margin in sports

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

    Laties, V.G.; Weiss, B.

    The amphetamines can enhance athletic performance. That much seem clear from the literature, some of which is reviewed here. Increases in endurance have been demonstrated in both humans and rats. Smith and Beecher, 20 years ago, showed improvement of running, swimming, and weight throwing in highly trained athletes. Laboratory analogs of such performances have also been used and similar enhancement demonstrated. The amount of change induced by the amphetamines is usually small, of the order of a few percent. Nevertheless, since a fraction of a percent improvement can make the difference between fame and oblivion, the margin conferred by thesemore » drugs can be quite important.« less

  6. Correction of rotational distortion for catheter-based en face OCT and OCT angiography

    PubMed Central

    Ahsen, Osman O.; Lee, Hsiang-Chieh; Giacomelli, Michael G.; Wang, Zhao; Liang, Kaicheng; Tsai, Tsung-Han; Potsaid, Benjamin; Mashimo, Hiroshi; Fujimoto, James G.

    2015-01-01

    We demonstrate a computationally efficient method for correcting the nonuniform rotational distortion (NURD) in catheter-based imaging systems to improve endoscopic en face optical coherence tomography (OCT) and OCT angiography. The method performs nonrigid registration using fiducial markers on the catheter to correct rotational speed variations. Algorithm performance is investigated with an ultrahigh-speed endoscopic OCT system and micromotor catheter. Scan nonuniformity is quantitatively characterized, and artifacts from rotational speed variations are significantly reduced. Furthermore, we present endoscopic en face OCT and OCT angiography images of human gastrointestinal tract in vivo to demonstrate the image quality improvement using the correction algorithm. PMID:25361133

  7. Case Study for the ARRA-funded Ground Source Heat Pump (GSHP) Demonstration at Wilders Grove Solid Waste Service Center in Raleigh, NC

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

    Liu, Xiaobing; Malhotra, Mini; Xiong, Zeyu

    High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects, a distributed GSHP system for providing all the space conditioning, outdoor air ventilation, and 100% domestic hot water tomore » the Wilders Grove Solid Waste Service Center of City of Raleigh, North Carolina. This case study is based on the analysis of measured performance data, construction costs, and simulations of the energy consumption of conventional central heating, ventilation, and air-conditioning (HVAC) systems providing the same level of space conditioning and outdoor air ventilation as the demonstrated GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the GSHP system compared with conventional HVAC systems. This case study also identified opportunities for reducing uncertainties in the performance evaluation and improving the operational efficiency of the demonstrated GSHP system.« less

  8. Exercise training for intermittent claudication.

    PubMed

    McDermott, Mary M

    2017-11-01

    The objective of this study was to provide an overview of evidence regarding exercise therapies for patients with lower extremity peripheral artery disease (PAD). This manuscript summarizes the content of a lecture delivered as part of the 2016 Crawford Critical Issues Symposium. Multiple randomized clinical trials demonstrate that supervised treadmill exercise significantly improves treadmill walking performance in people with PAD and intermittent claudication symptoms. A meta-analysis of 25 randomized trials demonstrated a 180-meter increase in treadmill walking distance in response to supervised exercise interventions compared with a nonexercising control group. Supervised treadmill exercise has been inaccessible to many patients with PAD because of lack of medical insurance coverage. However, in 2017, the Centers for Medicare and Medicaid Services issued a decision memorandum to support health insurance coverage of 12 weeks of supervised treadmill exercise for patients with walking impairment due to PAD. Recent evidence also supports home-based walking exercise to improve walking performance in people with PAD. Effective home-exercise programs incorporate behavioral change interventions such as a remote coach, goal setting, and self-monitoring. Supervised treadmill exercise programs preferentially improve treadmill walking performance, whereas home-based walking exercise programs preferentially improve corridor walking, such as the 6-minute walk test. Clinical trial evidence also supports arm or leg ergometry exercise to improve walking endurance in people with PAD. Treadmill walking exercise appears superior to resistance training alone for improving walking endurance. Supervised treadmill exercise significantly improves treadmill walking performance in people with PAD by approximately 180 meters compared with no exercise. Recent evidence suggests that home-based exercise is also effective and preferentially improves over-ground walking performance, such as the 6-minute walk test. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  9. Wave rotor demonstrator engine assessment

    NASA Technical Reports Server (NTRS)

    Snyder, Philip H.

    1996-01-01

    The objective of the program was to determine a wave rotor demonstrator engine concept using the Allison 250 series engine. The results of the NASA LERC wave rotor effort were used as a basis for the wave rotor design. A wave rotor topped gas turbine engine was identified which incorporates five basic requirements of a successful demonstrator engine. Predicted performance maps of the wave rotor cycle were used along with maps of existing gas turbine hardware in a design point study. The effects of wave rotor topping on the engine cycle and the subsequent need to rematch compressor and turbine sections in the topped engine were addressed. Comparison of performance of the resulting engine is made on the basis of wave rotor topped engine versus an appropriate baseline engine using common shaft compressor hardware. The topped engine design clearly demonstrates an impressive improvement in shaft horsepower (+11.4%) and SFC (-22%). Off design part power engine performance for the wave rotor topped engine was similarly improved including that at engine idle conditions. Operation of the engine at off design was closely examined with wave rotor operation at less than design burner outlet temperatures and rotor speeds. Challenges identified in the development of a demonstrator engine are discussed. A preliminary design was made of the demonstrator engine including wave rotor to engine transition ducts. Program cost and schedule for a wave rotor demonstrator engine fabrication and test program were developed.

  10. Thinking within the box: The relational processing style elicited by counterfactual mind-sets.

    PubMed

    Kray, Laura J; Galinsky, Adam D; Wong, Elaine M

    2006-07-01

    By comparing reality to what might have been, counterfactuals promote a relational processing style characterized by a tendency to consider relationships and associations among a set of stimuli. As such, counterfactual mind-sets were expected to improve performance on tasks involving the consideration of relationships and associations but to impair performance on tasks requiring novel ideas that are uninfluenced by salient associations. The authors conducted several experiments to test this hypothesis. In Experiments 1a and 1b, the authors determined that counterfactual mind-sets increase mental states and preferences for thinking styles consistent with relational thought. Experiment 2 demonstrated a facilitative effect of counterfactual mind-sets on an analytic task involving logical relationships; Experiments 3 and 4 demonstrated that counterfactual mind-sets structure thought and imagination around salient associations and therefore impaired performance on creative generation tasks. In Experiment 5, the authors demonstrated that the detrimental effect of counterfactual mind-sets is limited to creative tasks involving novel idea generation; in a creative association task involving the consideration of relationships between task stimuli, counterfactual mind-sets improved performance. Copyright 2006 APA, all rights reserved.

  11. Tips pentacene crystal alignment for improving performance of solution processed organic thin film transistors

    NASA Astrophysics Data System (ADS)

    He, Zhengran

    A newly-developed p-type organic semiconductor 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) demonstrates various advantages such as high mobility, air stability and solution processibility, but at the same time its application is restricted by major issues, such as crystal misorientation and performance variation of organic thin-film transistors (OTFTs). This dissertation demonstrates several different approaches to address these issues. As a result, both crystal orientation and areal coverage can be effectively improved, leading to an enhancement of average mobility and performance consistency of OTFTs. Chapter 1 presents an introduction and background of this dissertation. Chapter 2 explores the usage of inorganic silica nanoparticles to manipulate the morphology of TIPS pentacene thin films and the performance of solution-processed organic OTFTs. The resultant drop-cast films yield improved morphological uniformity at ~10% SiO2 loading, which also leads to a 3-fold increase in average mobility and nearly 4-times reduction in the ratio of standard deviation of mobility (μStdev) to average mobility (μAvg). The experimental results suggest that the SiO2 nanoparticles mostly aggregate at TIPS pentacene grain boundaries, and that 10% nanoparticle concentration effectively reduces the undesirable crystal misorientation without considerably compromising TIPS pentacene crystallinity. Chapter 3 discusses the utilization of air flow to effectively reduce the TIPS pentacene crystal anisotropy and enhance performance consistency in OTFTs. Under air-flow navigation (AFN), TIPS pentacene forms thin films with improved crystal orientation and increased areal coverage, which subsequently lead to a four-fold increase of average hole mobility and one order of magnitude enhancement in performance consistency. Chapter 4 investigates the critical roles of lateral and vertical phase separation in the performance of the next-generation organic and hybrid electronic devices. A novel method is demonstrated here to switch between lateral and vertical phase separation in semiconducting TIPS pentacene/ polymer blend films by simply varying the alkyl length of the polyacrylate polymer component. The phase separation modes depend on intermolecular interactions between small molecule TIPS pentacene and polymer additives. The blend film with a dominant vertical phase separation exhibits a significant enhancement in average mobility and performance consistency of organic OTFTs. Chapter 5 demonstrates an effective approach to improve both charge transport and performance consistency in solution-processed OTFTs by blending TIPS pentacene with a series of small-molecule additives: 4-butylbenzoic acid (BBA), 4-hexylbenzoic acid (HBA), and 4-octylbenzoic acid (OBA). These three small molecules share a benzoic acid moiety, but have different length of hydrophobic tails. The self-assembled interfacial layer of small molecules on the gate oxide surface leads to uniform deposition of TIPS pentacene crystal seeds and facilitates TIPS pentacene to grow along the tilted orientation of substrate, which results in a film of enhanced crystal orientation and areal coverage. OTFTs based on TIPS pentacene/small molecule blends demonstrate greatly improved average hole mobility and performance consistency, which correlates with the length of hydrophobic tail of the small-molecule additives. Chapter 6 summarizes the conclusions of this dissertation and the related future work.

  12. New Flexible Silicone-Based EEG Dry Sensor Material Compositions Exhibiting Improvements in Lifespan, Conductivity, and Reliability

    PubMed Central

    Yu, Yi-Hsin; Chen, Shih-Hsun; Chang, Che-Lun; Lin, Chin-Teng; Hairston, W. David; Mrozek, Randy A.

    2016-01-01

    This study investigates alternative material compositions for flexible silicone-based dry electroencephalography (EEG) electrodes to improve the performance lifespan while maintaining high-fidelity transmission of EEG signals. Electrode materials were fabricated with varying concentrations of silver-coated silica and silver flakes to evaluate their electrical, mechanical, and EEG transmission performance. Scanning electron microscope (SEM) analysis of the initial electrode development identified some weak points in the sensors’ construction, including particle pull-out and ablation of the silver coating on the silica filler. The newly-developed sensor materials achieved significant improvement in EEG measurements while maintaining the advantages of previous silicone-based electrodes, including flexibility and non-toxicity. The experimental results indicated that the proposed electrodes maintained suitable performance even after exposure to temperature fluctuations, 85% relative humidity, and enhanced corrosion conditions demonstrating improvements in the environmental stability. Fabricated flat (forehead) and acicular (hairy sites) electrodes composed of the optimum identified formulation exhibited low impedance and reliable EEG measurement; some initial human experiments demonstrate the feasibility of using these silicone-based electrodes for typical lab data collection applications. PMID:27809260

  13. New Flexible Silicone-Based EEG Dry Sensor Material Compositions Exhibiting Improvements in Lifespan, Conductivity, and Reliability.

    PubMed

    Yu, Yi-Hsin; Chen, Shih-Hsun; Chang, Che-Lun; Lin, Chin-Teng; Hairston, W David; Mrozek, Randy A

    2016-10-31

    This study investigates alternative material compositions for flexible silicone-based dry electroencephalography (EEG) electrodes to improve the performance lifespan while maintaining high-fidelity transmission of EEG signals. Electrode materials were fabricated with varying concentrations of silver-coated silica and silver flakes to evaluate their electrical, mechanical, and EEG transmission performance. Scanning electron microscope (SEM) analysis of the initial electrode development identified some weak points in the sensors' construction, including particle pull-out and ablation of the silver coating on the silica filler. The newly-developed sensor materials achieved significant improvement in EEG measurements while maintaining the advantages of previous silicone-based electrodes, including flexibility and non-toxicity. The experimental results indicated that the proposed electrodes maintained suitable performance even after exposure to temperature fluctuations, 85% relative humidity, and enhanced corrosion conditions demonstrating improvements in the environmental stability. Fabricated flat (forehead) and acicular (hairy sites) electrodes composed of the optimum identified formulation exhibited low impedance and reliable EEG measurement; some initial human experiments demonstrate the feasibility of using these silicone-based electrodes for typical lab data collection applications.

  14. Balance and gait improved in patients with MS after physiotherapy based on the Bobath concept.

    PubMed

    Smedal, Tori; Lygren, Hildegunn; Myhr, Kjell-Morten; Moe-Nilssen, Rolf; Gjelsvik, Bente; Gjelsvik, Olav; Strand, Liv Inger; Inger, Liv

    2006-06-01

    Patients with multiple sclerosis (MS) tend to have movement difficulties, and the effect of physiotherapy for this group of patients has been subjected to limited systematic research. In the present study physiotherapy based on the Bobath concept, applied to MS patients with balance and gait problems, was evaluated. The ability of different functional tests to demonstrate change was evaluated. A single-subject experimental study design with ABAA phases was used, and two patients with relapsing-remitting MS in stable phase were treated. Tests were performed 12 times, three at each phase: A (at baseline); B (during treatment); A (immediately after treatment); and A (after two months). The key feature of treatment was facilitation of postural activity and selective control of movement. Several performance and self report measures and interviews were used. After intervention, improved balance was shown by the Berg Balance Scale (BBS) in both patients, and improved quality of gait was indicated by the Rivermead Visual Gait Assessment (RVGA). The patients also reported improved balance and gait function in the interviews and scored their condition as 'much improved'. Gait parameters, recorded by an electronic walkway, changed, but differently in the two patients. Among the physical performance tests the BBS and the RVGA demonstrated the highest change, while no or minimal change was demonstrated by the Rivermead Mobility Index (RMI) and Ratings of Perceived Exertion (RPE). The findings indicate that balance and gait can be improved after physiotherapy based on the Bobath concept, but this should be further evaluated in larger controlled trials of patients with MS.

  15. Rotor design optimization using a free wake analysis

    NASA Technical Reports Server (NTRS)

    Quackenbush, Todd R.; Boschitsch, Alexander H.; Wachspress, Daniel A.; Chua, Kiat

    1993-01-01

    The aim of this effort was to develop a comprehensive performance optimization capability for tiltrotor and helicopter blades. The analysis incorporates the validated EHPIC (Evaluation of Hover Performance using Influence Coefficients) model of helicopter rotor aerodynamics within a general linear/quadratic programming algorithm that allows optimization using a variety of objective functions involving the performance. The resulting computer code, EHPIC/HERO (HElicopter Rotor Optimization), improves upon several features of the previous EHPIC performance model and allows optimization utilizing a wide spectrum of design variables, including twist, chord, anhedral, and sweep. The new analysis supports optimization of a variety of objective functions, including weighted measures of rotor thrust, power, and propulsive efficiency. The fundamental strength of the approach is that an efficient search for improved versions of the baseline design can be carried out while retaining the demonstrated accuracy inherent in the EHPIC free wake/vortex lattice performance analysis. Sample problems are described that demonstrate the success of this approach for several representative rotor configurations in hover and axial flight. Features that were introduced to convert earlier demonstration versions of this analysis into a generally applicable tool for researchers and designers is also discussed.

  16. Field Test Results of Using a Nacelle-Mounted Lidar for Improving Wind Energy Capture by Reducing Yaw Misalignment (Presentation)

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

    Fleming, P.; Scholbrock, A.; Wright, A.

    2014-11-01

    Presented at the Nordic Wind Power Conference on November 5, 2014. This presentation describes field-test campaigns performed at the National Wind Technology Center in which lidar technology was used to improve the yaw alignment of the Controls Advanced Research Turbine (CART) 2 and CART3 wind turbines. The campaigns demonstrated that whether by learning a correction function to the nacelle vane, or by controlling yaw directly with the lidar signal, a significant improvement in power capture was demonstrated.

  17. Diagnostic colonoscopy: performance measurement study.

    PubMed

    Kuznets, Naomi

    2002-07-01

    This is the fifth of a series of best practices studies undertaken by the Performance Measurement Initiative (PMI), the centerpiece of the Institute for Quality Improvement (IQI), a not-for-profit quality improvement subsidiary of the Accreditation Association for Ambulatory Health Care (AAAHC) (Performance Measurement Initiative, 1999a, 1999b, 2000a, 2000b). The IQI was created to offer clinical performance measurement and improvement opportunities to ambulatory health care organizations and others interested in quality patient care. The purpose of the study was to provide opportunities to initiate clinical performance measurement on key processes and outcomes for this procedure and use this information for clinical quality improvement. This article provides performance measurement information on how organizations that have demonstrated and validated differences in clinical practice can have similar outcomes, but at a dramatically lower cost. The intent of the article is to provide organizations with alternatives in practice to provide a better value to their patients.

  18. Propulsion system-flight control integration-flight evaluation and technology transition

    NASA Technical Reports Server (NTRS)

    Burcham, Frank W., Jr.; Gilyard, Glenn B.; Myers, Lawrence P.

    1990-01-01

    Integration of propulsion and flight control systems and their optimization offering significant performance improvement are assessed. In particular, research programs conducted by NASA on flight control systems and propulsion system-flight control interactions on the YF-12 and F-15 aircraft are addressed; these programs have demonstrated increased thrust, reduced fuel consumption, increased engine life, and improved aircraft performance. Focus is placed on altitude control, speed-Mach control, integrated controller design, as well as flight control systems and digital electronic engine control. A highly integrated digital electronic control program is analyzed and compared with a performance seeking control program. It is shown that the flight evaluation and demonstration of these technologies have been a key part in the transition of the concepts to production and operational use on a timely basis.

  19. Adaptive Residual Interpolation for Color and Multispectral Image Demosaicking †

    PubMed Central

    Kiku, Daisuke; Okutomi, Masatoshi

    2017-01-01

    Color image demosaicking for the Bayer color filter array is an essential image processing operation for acquiring high-quality color images. Recently, residual interpolation (RI)-based algorithms have demonstrated superior demosaicking performance over conventional color difference interpolation-based algorithms. In this paper, we propose adaptive residual interpolation (ARI) that improves existing RI-based algorithms by adaptively combining two RI-based algorithms and selecting a suitable iteration number at each pixel. These are performed based on a unified criterion that evaluates the validity of an RI-based algorithm. Experimental comparisons using standard color image datasets demonstrate that ARI can improve existing RI-based algorithms by more than 0.6 dB in the color peak signal-to-noise ratio and can outperform state-of-the-art algorithms based on training images. We further extend ARI for a multispectral filter array, in which more than three spectral bands are arrayed, and demonstrate that ARI can achieve state-of-the-art performance also for the task of multispectral image demosaicking. PMID:29194407

  20. Adaptive Residual Interpolation for Color and Multispectral Image Demosaicking.

    PubMed

    Monno, Yusuke; Kiku, Daisuke; Tanaka, Masayuki; Okutomi, Masatoshi

    2017-12-01

    Color image demosaicking for the Bayer color filter array is an essential image processing operation for acquiring high-quality color images. Recently, residual interpolation (RI)-based algorithms have demonstrated superior demosaicking performance over conventional color difference interpolation-based algorithms. In this paper, we propose adaptive residual interpolation (ARI) that improves existing RI-based algorithms by adaptively combining two RI-based algorithms and selecting a suitable iteration number at each pixel. These are performed based on a unified criterion that evaluates the validity of an RI-based algorithm. Experimental comparisons using standard color image datasets demonstrate that ARI can improve existing RI-based algorithms by more than 0.6 dB in the color peak signal-to-noise ratio and can outperform state-of-the-art algorithms based on training images. We further extend ARI for a multispectral filter array, in which more than three spectral bands are arrayed, and demonstrate that ARI can achieve state-of-the-art performance also for the task of multispectral image demosaicking.

  1. Demonstration and evaluation of gas turbine transit buses

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Gas Turbine Transit Bus Demonstration Program was designed to demonstrate and evaluate the operation of gas turbine engines in transit coaches in revenue service compared with diesel powered coaches. The main objective of the program was to accelerate development and commercialization of automotive gas turbines. The benefits from the installation of this engine in a transit coach were expected to be reduced weight, cleaner exhaust emissions, lower noise levels, reduced engine vibration and maintenance requirements, improved reliability and vehicle performance, greater engine braking capability, and superior cold weather starting. Four RTS-II advanced design transit coaches were converted to gas turbine power using engines and transmissions. Development, acceptance, performance and systems tests were performed on the coaches prior to the revenue service demonstration.

  2. Sensorimotor Adaptability Training Improves Motor and Dual-Task Performance

    NASA Technical Reports Server (NTRS)

    Bloomberg, J.J.; Peters, B.T.; Mulavara, A.P.; Brady, R.; Batson, C.; Cohen, H.S.

    2009-01-01

    The overall objective of our project is to develop a sensorimotor adaptability (SA) training program designed to facilitate recovery of functional capabilities when astronauts transition to different gravitational environments. The goal of our current study was to determine if SA training using variation in visual flow and support surface motion produces improved performance in a novel sensory environment and demonstrate the retention characteristics of SA training.

  3. Improving Working Memory in Children with Attention-Deficit/Hyperactivity Disorder: The Separate and Combined Effects of Incentives and Stimulant Medication

    ERIC Educational Resources Information Center

    Strand, Michael T.; Hawk, Larry W., Jr.; Bubnik, Michelle; Shiels, Keri; Pelham, William E., Jr.; Waxmonsky, James G.

    2012-01-01

    Working memory (WM) is considered a core deficit in Attention-Deficit/Hyperactivity Disorder (ADHD), with numerous studies demonstrating impaired WM among children with ADHD. We tested the degree to which WM in children with ADHD was improved by performance-based incentives, an analog of behavioral intervention. In two studies, WM performance was…

  4. Testing Report: Littleford-Day Dryer Operation: Dryer Operation Impacts of Proposed MIS Mitigation Changes

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

    Shimskey, Rick W.; Buchmiller, William C.; Elmore, Monte R.

    2007-06-01

    Pacific Northwest National Laboratory performed a series of tests using the Littleford Day 22-liter dryer during investigations that evaluated changes in the melter-feed composition for the Demonstration Bulk Vitrification System. During testing, a new melter-feed formulation was developed that improved dryer performance while improving the retention of waste salts in the melter feed during vitrification.

  5. Performance Contracting as a Performance Management Tool in the Public Sector in Kenya: Lessons of learning

    ERIC Educational Resources Information Center

    Hope, Kempe Ronald, Sr.

    2013-01-01

    The purpose of this article is to provide an assessment and analysis of public sector performance contracting as a performance management tool in Kenya. It aims to demonstrate that performance contracting remains a viable and important tool for improving public sector performance as a key element of the on-going public sector transformation…

  6. Solid Polymer Electrolyte (SPE) fuel cell technology program

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Many previously demonstrated improved fuel cell features were consolidated to (1) obtain a better understanding of the observed characteristics of the operating laboratory-sized cells; (2) evaluate appropriate improved fuel cell features in 0.7 sq ft cell hardware; and (3) study the resultant fuel cell capability and determine its impact on various potential fuel cell space missions. The observed performance characteristics of the fuel cell at high temperatures and high current densities were matched with a theoretical model based on the change in Gibbs free energy voltage with respect to temperature and internal resistance change with current density. Excellent agreement between the observed and model performance was obtained. The observed performance decay with operational time on cells with very low noble metal loadings (0.05 mg/sq cm) were shown to be related to loss in surface area. Cells with the baseline amount of noble catalyst electrode loading demonstrated over 40,000 hours of stable performance.

  7. Piezoresistive Cantilever Performance—Part II: Optimization

    PubMed Central

    Park, Sung-Jin; Doll, Joseph C.; Rastegar, Ali J.; Pruitt, Beth L.

    2010-01-01

    Piezoresistive silicon cantilevers fabricated by ion implantation are frequently used for force, displacement, and chemical sensors due to their low cost and electronic readout. However, the design of piezoresistive cantilevers is not a straightforward problem due to coupling between the design parameters, constraints, process conditions, and performance. We systematically analyzed the effect of design and process parameters on force resolution and then developed an optimization approach to improve force resolution while satisfying various design constraints using simulation results. The combined simulation and optimization approach is extensible to other doping methods beyond ion implantation in principle. The optimization results were validated by fabricating cantilevers with the optimized conditions and characterizing their performance. The measurement results demonstrate that the analytical model accurately predicts force and displacement resolution, and sensitivity and noise tradeoff in optimal cantilever performance. We also performed a comparison between our optimization technique and existing models and demonstrated eight times improvement in force resolution over simplified models. PMID:20333323

  8. Computational Fluid Dynamics Simulation Study of Active Power Control in Wind Plants

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

    Fleming, Paul; Aho, Jake; Gebraad, Pieter

    2016-08-01

    This paper presents an analysis performed on a wind plant's ability to provide active power control services using a high-fidelity computational fluid dynamics-based wind plant simulator. This approach allows examination of the impact on wind turbine wake interactions within a wind plant on performance of the wind plant controller. The paper investigates several control methods for improving performance in waked conditions. One method uses wind plant wake controls, an active field of research in which wind turbine control systems are coordinated to account for their wakes, to improve the overall performance. Results demonstrate the challenge of providing active power controlmore » in waked conditions but also the potential methods for improving this performance.« less

  9. Device Engineering Towards Improved Tin Sulfide Solar Cell Performance and Performance Reproducibility

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

    Steinmann, Vera; Chakraborty, Rupak; Rekemeyer, Paul

    2016-11-21

    As novel absorber materials are developed and screened for their photovoltaic (PV) properties, the challenge remains to rapidly test promising candidates in high-performing PV devices. There is a need to engineer new compatible device architectures, including the development of novel transparent conductive oxides and buffer layers. Here, we consider the two approaches of a substrate-style and a superstrate-style device architecture for novel thin-film solar cells. We use tin sulfide as a test absorber material. Upon device engineering, we demonstrate new approaches to improve device performance and performance reproducibility.

  10. Accelerating Sequences in the Presence of Metal by Exploiting the Spatial Distribution of Off-Resonance

    PubMed Central

    Smith, Matthew R.; Artz, Nathan S.; Koch, Kevin M.; Samsonov, Alexey; Reeder, Scott B.

    2014-01-01

    Purpose To demonstrate feasibility of exploiting the spatial distribution of off-resonance surrounding metallic implants for accelerating multispectral imaging techniques. Theory Multispectral imaging (MSI) techniques perform time-consuming independent 3D acquisitions with varying RF frequency offsets to address the extreme off-resonance from metallic implants. Each off-resonance bin provides a unique spatial sensitivity that is analogous to the sensitivity of a receiver coil, and therefore provides a unique opportunity for acceleration. Methods Fully sampled MSI was performed to demonstrate retrospective acceleration. A uniform sampling pattern across off-resonance bins was compared to several adaptive sampling strategies using a total hip replacement phantom. Monte Carlo simulations were performed to compare noise propagation of two of these strategies. With a total knee replacement phantom, positive and negative off-resonance bins were strategically sampled with respect to the B0 field to minimize aliasing. Reconstructions were performed with a parallel imaging framework to demonstrate retrospective acceleration. Results An adaptive sampling scheme dramatically improved reconstruction quality, which was supported by the noise propagation analysis. Independent acceleration of negative and positive off-resonance bins demonstrated reduced overlapping of aliased signal to improve the reconstruction. Conclusion This work presents the feasibility of acceleration in the presence of metal by exploiting the spatial sensitivities of off-resonance bins. PMID:24431210

  11. Microwave photonic link with improved phase noise using a balanced detection scheme

    NASA Astrophysics Data System (ADS)

    Hu, Jingjing; Gu, Yiying; Tan, Wengang; Zhu, Wenwu; Wang, Linghua; Zhao, Mingshan

    2016-07-01

    A microwave photonic link (MPL) with improved phase noise performance using a dual output Mach-Zehnder modulator (DP-MZM) and balanced detection is proposed and experimentally demonstrated. The fundamental concept of the approach is based on the two complementary outputs of DP-MZM and the destructive combination of the photocurrent in balanced photodetector (BPD). Theoretical analysis is performed to numerical evaluate the additive phase noise performance and shows a good agreement with the experiment. Experimental results are presented for 4 GHz, 8 GHz and 12 GHz transmission link and an 11 dB improvement of phase noise performance at 10 MHz offset is achieved compared to the conventional intensity-modulation and direct-detection (IMDD) MPL.

  12. On improving the performance of nonphotochemical quenching in CP29 light-harvesting antenna complex

    NASA Astrophysics Data System (ADS)

    Berman, Gennady P.; Nesterov, Alexander I.; Sayre, Richard T.; Still, Susanne

    2016-03-01

    We model and simulate the performance of charge-transfer in nonphotochemical quenching (NPQ) in the CP29 light-harvesting antenna-complex associated with photosystem II (PSII). The model consists of five discrete excitonic energy states and two sinks, responsible for the potentially damaging processes and charge-transfer channels, respectively. We demonstrate that by varying (i) the parameters of the chlorophyll-based dimer, (ii) the resonant properties of the protein-solvent environment interaction, and (iii) the energy transfer rates to the sinks, one can significantly improve the performance of the NPQ. Our analysis suggests strategies for improving the performance of the NPQ in response to environmental changes, and may stimulate experimental verification.

  13. A systematic review to evaluate the effectiveness of carnitine supplementation in improving walking performance among individuals with intermittent claudication.

    PubMed

    Delaney, Christopher L; Spark, J Ian; Thomas, Jolene; Wong, Yew Toh; Chan, Lok Tsung; Miller, Michelle D

    2013-07-01

    To evaluate the evidence for the use of carnitine supplementation in improving walking performance among individuals with intermittent claudication. Systematic review. An electronic search of the literature was performed using MEDLINE (PubMed), Scopus, Cochrane Central Register of Controlled Trials and The Cochrane Library from inception through to November 2012. Search terms included peripheral arterial disease, intermittent claudication and carnitine. Reference lists of review articles and primary studies were also examined. Full reports of published experimental studies including randomized controlled trials and pre-test/post-test trials were selected for inclusion. A quality assessment was undertaken according to the Jadad scale. A total of 40 articles were retrieved, of which 23 did not meet the inclusion criteria. The 17 included articles reported on a total of 18 experimental studies of carnitine supplementation (5 pre-test/post-test; 8 parallel RCT; 5 cross-over RCT) for improving walking performance in adults with intermittent claudication. For pre-test/post-test studies, 300-2000 mg propionyl-L-carnitine (PLC) was administered orally or intravenously for a maximum of 90 days (7-42 participants) with statistically significant improvements of between 74 m and 157 m in pain free walking distance and between 71 m and 135 m in maximal walking distance across 3 out of 5 studies. Similarly, PLC (600 mg-3000 mg) was administered orally in 7 out of 8 parallel RCTs (22-485 participants), the longest duration being 12 months. All but one of the smallest trials demonstrated statistically significant improvements in walking performance between 31 and 54 m greater than placebo for pain free walking distance and between 9 and 86 m greater than placebo for maximal walking distance. A double-blind parallel RCT of cilostazol plus 2000 mg oral L-carnitine or placebo for 180 days (145 participants) did not demonstrate any significant improvement in walking performance. Of 5 cross-over RCTs (8-20 participants), 4 demonstrated significant improvements in walking performance following administration of 300-6000 mg L-carnitine or PLC. Compared to placebo, pain free walking distance and maximal walking distance improved by 23-132 m and 104 m respectively following carnitine intervention. Most trials demonstrated a small or modest improvement in walking performance with administration of PLC or L-carnitine. These findings were largely independent of level or quality of evidence, while there was some evidence that intravenous administration was more effective than oral administration and those with severe claudication may achieve greater benefits than those with moderate claudication. Routine carnitine supplementation in the form of PLC may therefore be a useful adjunct therapy for management of intermittent claudication. Further research is warranted to determine the optimal form, duration, dose and safety of carnitine supplementation across the spectrum of peripheral arterial disease severity and its effect with concurrent supervised exercise programs and best medical therapy. These studies should be supplemented with cost effectiveness studies to ensure that the return on the investment is acceptable. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  14. Influence of learning style on instructional multimedia effects on graduate student cognitive and psychomotor performance.

    PubMed

    Smith, A Russell; Cavanaugh, Catherine; Jones, Joyce; Venn, John; Wilson, William

    2006-01-01

    Learning outcomes may improve in graduate healthcare students when attention is given to individual learning styles. Interactive multimedia is one tool shown to increase success in meeting the needs of diverse learners. The purpose of this study was to examine the effect of learning style and type of instruction on physical therapy students' cognitive and psychomotor performance. Participants were obtained by a sample of convenience with students recruited from two physical therapy programs. Twenty-seven students volunteered to participate from Program 1. Twenty-three students volunteered to participate from Program 2. Gregorc learning styles were identified through completion of the Gregorc Style Delineator. Students were randomly assigned to one of two instructional strategies: 1) instructional CD or 2) live demonstration. Differences in cognitive or psychomotor performance following instructional multimedia based on learning style were not demonstrated in this study. Written examination scores improved with both instructional strategies demonstrating no differences between the strategies. Practical examination ankle scores were significantly higher in participants receiving CD instruction than in participants receiving live presentation. Learning style did not significantly affect this improvement. Program 2 performed significantly better on written knee and practical knee and ankle examinations. Learning style had no significant effect on student performance following instruction in clinical skills via interactive multimedia. Future research may include additional measurement instruments assessing other models of learning styles and possible interaction of learning style and instructional strategy on students over longer periods of time, such as a semester or an entire curriculum.

  15. Final Technical Report

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

    Stoessel, Chris

    2013-11-13

    This project developed a new high-performance R-10/high SHGC window design, reviewed market positioning and evaluated manufacturing solutions required for broad market adoption. The project objectives were accomplished by: identifying viable technical solutions based on modeling of modern and potential coating stacks and IGU designs; development of new coating material sets for HM thin film stacks, as well as improved HM IGU designs to accept multiple layers of HM films; matching promising new coating designs with new HM IGU designs to demonstrate performance gains; and, in cooperation with a window manufacturer, assess the potential for high-volume manufacturing and cost efficiency ofmore » a HM-based R-10 window with improved solar heat gain characteristics. A broad view of available materials and design options was applied to achieve the desired improvements. Gated engineering methodologies were employed to guide the development process from concept generation to a window demonstration. The project determined that a slightly de-rated window performance allows formulation of a path to achieve the desired cost reductions to support end consumer adoption.« less

  16. Effects of a 6-month exercise program pilot study on walking economy, peak physiological characteristics, and walking performance in patients with peripheral arterial disease.

    PubMed

    Crowther, Robert G; Leicht, Anthony S; Spinks, Warwick L; Sangla, Kunwarjit; Quigley, Frank; Golledge, Jonathan

    2012-01-01

    The purpose of this study was to examine the effects of a 6-month exercise program on submaximal walking economy in individuals with peripheral arterial disease and intermittent claudication (PAD-IC). Participants (n = 16) were randomly allocated to either a control PAD-IC group (CPAD-IC, n = 6) which received standard medical therapy, or a treatment PAD-IC group (TPAD-IC; n = 10) which took part in a supervised exercise program. During a graded treadmill test, physiological responses, including oxygen consumption, were assessed to calculate walking economy during submaximal and maximal walking performance. Differences between groups at baseline and post-intervention were analyzed via Kruskal-Wallis tests. At baseline, CPAD-IC and TPAD-IC groups demonstrated similar walking performance and physiological responses. Postintervention, TPAD-IC patients demonstrated significantly lower oxygen consumption during the graded exercise test, and greater maximal walking performance compared to CPAD-IC. These preliminary results indicate that 6 months of regular exercise improves both submaximal walking economy and maximal walking performance, without significant changes in maximal walking economy. Enhanced walking economy may contribute to physiological efficiency, which in turn may improve walking performance as demonstrated by PAD-IC patients following regular exercise programs.

  17. Improved physical fitness correlates with improved cognition in multiple sclerosis.

    PubMed

    Beier, Meghan; Bombardier, Charles H; Hartoonian, Narineh; Motl, Robert W; Kraft, George H

    2014-07-01

    To determine whether there is an association between improvements in objective measures of physical fitness and performance on cognitive tests in people with multiple sclerosis (MS). Post hoc correlational analysis in which people demonstrating physical improvement were compared with those not demonstrating physical improvement. Individuals with MS residing in the community. Adults with clinically confirmed MS (N=88) who participated in a controlled trial of a telephone-based health promotion intervention, chose to work on exercise, and completed the pre- and postintervention assessments. Participants were measured for strength (isokinetic dynamometer), aerobic fitness (bicycle ergometer), and cognition (Paced Auditory Serial Addition Test [PASAT], Trail Making Test [TMT]) at baseline and 12 weeks later. Change in fitness was calculated by subtracting each participant's baseline score from the outcome score, and then transforming the difference to a z score. Individuals with a z score ≥1 on any fitness measure were placed in the physically improved group (n=25). All others were in the physically not improved group (n=57). After controlling for covariates (age, sex, ethnicity, education, disease activity, MS type), there was a significant group-by-time interaction, suggesting that cognitive functioning changed over time based on level of fitness. Participants in the physically improved group demonstrated improved performance on measures of executive functioning after 12 weeks of exercise. The results of this study lend support to the hypothesis that change in fitness is associated with improved executive functioning in people with MS. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Practical Approaches to Quality Improvement for Radiologists.

    PubMed

    Kelly, Aine Marie; Cronin, Paul

    2015-10-01

    Continuous quality improvement is a fundamental attribute of high-performing health care systems. Quality improvement is an essential component of health care, with the current emphasis on adding value. It is also a regulatory requirement, with reimbursements increasingly being linked to practice performance metrics. Practice quality improvement efforts must be demonstrated for credentialing purposes and for certification of radiologists in practice. Continuous quality improvement must occur for radiologists to remain competitive in an increasingly diverse health care market. This review provides an introduction to the main approaches available to undertake practice quality improvement, which will be useful for busy radiologists. Quality improvement plays multiple roles in radiology services, including ensuring and improving patient safety, providing a framework for implementing and improving processes to increase efficiency and reduce waste, analyzing and depicting performance data, monitoring performance and implementing change, enabling personnel assessment and development through continued education, and optimizing customer service and patient outcomes. The quality improvement approaches and underlying principles overlap, which is not surprising given that they all align with good patient care. The application of these principles to radiology practices not only benefits patients but also enhances practice performance through promotion of teamwork and achievement of goals. © RSNA, 2015.

  19. Improving the Test-Taking Skills of Learning Disabled Students.

    ERIC Educational Resources Information Center

    Scruggs, Thomas E.; Jenkins, Vesna

    Research on test taking skills of LD (learning disabled) students is reviewed and implications for improving the skill are noted. Among findings considered are that separate answer sheets appear to inhibit the performance of LD students, LD students can benefit from training and demonstrate improved attitudes toward testing, and students should…

  20. Preparing systems engineering and computing science students in disciplined methods, quantitative, and advanced statistical techniques to improve process performance

    NASA Astrophysics Data System (ADS)

    McCray, Wilmon Wil L., Jr.

    The research was prompted by a need to conduct a study that assesses process improvement, quality management and analytical techniques taught to students in U.S. colleges and universities undergraduate and graduate systems engineering and the computing science discipline (e.g., software engineering, computer science, and information technology) degree programs during their academic training that can be applied to quantitatively manage processes for performance. Everyone involved in executing repeatable processes in the software and systems development lifecycle processes needs to become familiar with the concepts of quantitative management, statistical thinking, process improvement methods and how they relate to process-performance. Organizations are starting to embrace the de facto Software Engineering Institute (SEI) Capability Maturity Model Integration (CMMI RTM) Models as process improvement frameworks to improve business processes performance. High maturity process areas in the CMMI model imply the use of analytical, statistical, quantitative management techniques, and process performance modeling to identify and eliminate sources of variation, continually improve process-performance; reduce cost and predict future outcomes. The research study identifies and provides a detail discussion of the gap analysis findings of process improvement and quantitative analysis techniques taught in U.S. universities systems engineering and computing science degree programs, gaps that exist in the literature, and a comparison analysis which identifies the gaps that exist between the SEI's "healthy ingredients " of a process performance model and courses taught in U.S. universities degree program. The research also heightens awareness that academicians have conducted little research on applicable statistics and quantitative techniques that can be used to demonstrate high maturity as implied in the CMMI models. The research also includes a Monte Carlo simulation optimization model and dashboard that demonstrates the use of statistical methods, statistical process control, sensitivity analysis, quantitative and optimization techniques to establish a baseline and predict future customer satisfaction index scores (outcomes). The American Customer Satisfaction Index (ACSI) model and industry benchmarks were used as a framework for the simulation model.

  1. Performance tests of a two phase ejector

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

    Harrell, G.S.; Kornhauser, A.A.

    1995-12-31

    The ejector expansion refrigeration cycle is a modified vapor compression cycle in which a two phase ejector is used to recover a portion of the work otherwise lost in the expansion valve. The ejector improves cycle performance by increasing compressor inlet pressure and by lowering the quality of liquid entering the evaporator. Theoretically, a cooling COP improvement of approximately 23% is achievable for a typical refrigerating cycle and an ideal ejector. If the ejector performed as well as typical single phase ejectors an improvement of 12% could be achieved. Previous tests have demonstrated a smaller 3.7% improvement; the difference ismore » in the poor performance of the two phase ejector. The purpose of this research is to understand the operating characteristics of the two phase ejector and to devise design improvements. A two phase ejector test rig has been constructed and tested. Preliminary data show performance superior to previously tested two phase ejectors, but still inferior to single phase ejectors. Ejector performance corresponds to refrigeration cycle COP improvements ranging from 3.9% to 7.6%.« less

  2. Real-time fMRI training-induced changes in regional connectivity mediating verbal working memory behavioral performance.

    PubMed

    Shen, J; Zhang, G; Yao, L; Zhao, X

    2015-03-19

    Working memory refers to the ability to temporarily store and manipulate information that is necessary for complex cognition activities. Previous studies have demonstrated that working memory capacity can be improved by behavioral training, and brain activities in the frontal and parietal cortices and the connections between these regions are also altered by training. Our recent neurofeedback training has proven that the regulation of the left dorsal lateral prefrontal cortex (DLPFC) activity using real-time functional magnetic resonance imaging (rtfMRI) can improve working memory performance. However, how working memory training promotes interaction between brain regions and whether this promotion correlates with performance improvement remain unclear. In this study, we employed structural equation modeling (SEM) to calculate the interactions between the regions within the working memory network during neurofeedback training. The results revealed that the direct effect of the frontoparietal connection in the left hemisphere was enhanced by the rtfMRI training. Specifically, the increase in the path from the left DLPFC to the left inferior parietal lobule (IPL) was positively correlated with improved performance in verbal working memory. These findings demonstrate the important role of the frontoparietal connection in working memory training and suggest that increases in frontoparietal connectivity might be a key factor associated with behavioral improvement. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Biochemical Platform Processing Integration

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

    None

    The objective of this project is to facilitate deployment of enzyme-based biomass conversion technology. The immediate goal is to explore integration issues that impact process performance and to demonstrate improved performance of the lower-cost enzymes being developed by Genencor and Novozymes.

  4. Should they stay or should they go now? Exploring the impact of team familiarity on interprofessional team training outcomes.

    PubMed

    Joshi, Kavita; Hernandez, Jessica; Martinez, Joseph; AbdelFattah, Kareem; Gardner, Aimee K

    2018-02-01

    Although simulation is an effective method for enhancing team competencies, it is unclear how team familiarity impacts this process. We examined how team familiarity impacted team competencies. Trainees were assigned to stable or dynamic teams to participate in three simulated cases. Situation awareness (SA) data was collected through in-scenario freezes. The recorded performances were assessed for clinical effectiveness (ClinEff) and teamwork. All data are reported on a 1-100% (100% = perfect performance) scale. Forty-six trainees (23 General Surgery; 23 Emergency Medicine) were randomized by specialty into stable (N = 8) or dynamic (N = 7) groups. Overall changes from Sim 1 to Sim3 were 12.2% (p < 0.01), -1.1% (ns), and 7.1% (p < 0.01) for SA, ClinEff, and Teamwork, respectively. However, improvements differed by condition, with stable teams reflecting improvements in ClinEff (15.2%; p < 0.05), whereas dynamic team ClinEff improvement (8.7%) was not significant. Both groups demonstrated improvements in teamwork (stable = 9%, p < 0.05; dynamic = 4.9%, p < 0.05). Teams who continued to work together demonstrated increased improvements in clinical effectiveness and teamwork, while dynamic teams only demonstrated improvements in teamwork. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Wave-Rotor-Enhanced Gas Turbine Engine Demonstrator

    NASA Technical Reports Server (NTRS)

    Welch, Gerard E.; Paxson, Daniel E.; Wilson, Jack; Synder, Philip H.

    1999-01-01

    The U.S. Army Research Laboratory, NASA Glenn Research Center, and Rolls-Royce Allison are working collaboratively to demonstrate the benefits and viability of a wave-rotor-topped gas turbine engine. The self-cooled wave rotor is predicted to increase the engine overall pressure ratio and peak temperature by 300% and 25 to 30%. respectively, providing substantial improvements in engine efficiency and specific power. Such performance improvements would significantly reduce engine emissions and the fuel logistics trails of armed forces. Progress towards a planned demonstration of a wave-rotor-topped Rolls-Royce Allison model 250 engine has included completion of the preliminary design and layout of the engine, the aerodynamic design of the wave rotor component and prediction of its aerodynamic performance characteristics in on- and off-design operation and during transients, and the aerodynamic design of transition ducts between the wave rotor and the high pressure turbine. The topping cycle increases the burner entry temperature and poses a design challenge to be met in the development of the demonstrator engine.

  6. Improving Cover-Letter Writing Skills of Individuals with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Pennington, Robert; Delano, Monica; Scott, Renee

    2014-01-01

    We evaluated a multicomponent intervention for improving the cover-letter writing skills of individuals with intellectual disabilities. An intervention that included modeling, self-monitoring, prompting, and feedback increased correct performance for all participants. In addition, the skill was demonstrated across audiences.

  7. Caffeine Enhances Memory Performance in Young Adults during Their Non-optimal Time of Day

    PubMed Central

    Sherman, Stephanie M.; Buckley, Timothy P.; Baena, Elsa; Ryan, Lee

    2016-01-01

    Many college students struggle to perform well on exams in the early morning. Although students drink caffeinated beverages to feel more awake, it is unclear whether these actually improve performance. After consuming coffee (caffeinated or decaffeinated), college-age adults completed implicit and explicit memory tasks in the early morning and late afternoon (Experiment 1). During the morning, participants ingesting caffeine demonstrated a striking improvement in explicit memory, but not implicit memory. Caffeine did not alter memory performance in the afternoon. In Experiment 2, participants engaged in cardiovascular exercise in order to examine whether increases in physiological arousal similarly improved memory. Despite clear increases in physiological arousal, exercise did not improve memory performance compared to a stretching control condition. These results suggest that caffeine has a specific benefit for memory during students’ non-optimal time of day – early morning. These findings have real-world implications for students taking morning exams. PMID:27895607

  8. Changes in cerebro-cerebellar interaction during response inhibition after performance improvement.

    PubMed

    Hirose, Satoshi; Jimura, Koji; Kunimatsu, Akira; Abe, Osamu; Ohtomo, Kuni; Miyashita, Yasushi; Konishi, Seiki

    2014-10-01

    It has been demonstrated that motor learning is supported by the cerebellum and the cerebro-cerebellar interaction. Response inhibition involves motor responses and the higher-order inhibition that controls the motor responses. In this functional MRI study, we measured the cerebro-cerebellar interaction during response inhibition in two separate days of task performance, and detected the changes in the interaction following performance improvement. Behaviorally, performance improved in the second day, compared to the first day. The psycho-physiological interaction (PPI) analysis revealed the interaction decrease from the right inferior frontal cortex (rIFC) to the cerebellum (lobule VII or VI). It was also revealed that the interaction increased from the same cerebellar region to the primary motor area. These results suggest the involvement of the cerebellum in response inhibition, and raise the possibility that the performance improvement was supported by the changes in the cerebro-cerebellar interaction. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. A novel shape from focus method based on 3D steerable filters for improved performance on treating textureless region

    NASA Astrophysics Data System (ADS)

    Fan, Tiantian; Yu, Hongbin

    2018-03-01

    A novel shape from focus method combining 3D steerable filter for improved performance on treating textureless region was proposed in this paper. Different from conventional spatial methods focusing on the search of maximum edges' response to estimate the depth map, the currently proposed method took both of the edges' response and the axial imaging blur degree into consideration during treatment. As a result, more robust and accurate identification for the focused location can be achieved, especially when treating textureless objects. Improved performance in depth measurement has been successfully demonstrated from both of the simulation and experiment results.

  10. The impact of obesity surgery on musculoskeletal disease.

    PubMed

    El-Khani, Ussamah; Ahmed, Ahmed; Hakky, Sherif; Nehme, Jean; Cousins, Jonathan; Chahal, Harvinder; Purkayastha, Sanjay

    2014-12-01

    Obesity is an important modifiable risk factor for musculoskeletal disease. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-compliant systematic review of bariatric surgery on musculoskeletal disease symptoms was performed. One thousand nineteen papers were identified, of which 43 were eligible for data synthesis. There were 79 results across 24 studies pertaining to physical capacity, of which 53 (67 %) demonstrated statistically significant post-operative improvement. There were 75 results across 33 studies pertaining to musculoskeletal pain, of which 42 (56 %) demonstrated a statistically significant post-operative improvement. There were 13 results across 6 studies pertaining to arthritis, of which 5 (38 %) demonstrated a statistically significant post-operative improvement. Bariatric surgery significantly improved musculoskeletal disease symptoms in 39 of the 43 studies. These changes were evident in a follow-up of 1 month to 10 years.

  11. Recrystallized arrays of bismuth nanowires with trigonal orientation.

    PubMed

    Limmer, Steven J; Yelton, W Graham; Erickson, Kristopher J; Medlin, Douglas L; Siegal, Michael P

    2014-01-01

    We demonstrate methods to improve the crystalline-quality of free-standing Bi nanowires arrays on a Si substrate and enhance the preferred trigonal orientation for thermoelectric performance by annealing the arrays above the 271.4 °C Bi melting point. The nanowires maintain their geometry during melting due to the formation of a thin Bi-oxide protective shell that contains the molten Bi. Recrystallizing nanowires from the melt improves crystallinity; those cooled rapidly demonstrate a strong trigonal orientation preference.

  12. Talk aloud problem solving: Exploration of acquisition and frequency building in science text

    NASA Astrophysics Data System (ADS)

    Dembek, Ginny

    Discovering new ways to help students attain higher levels of scientific knowledge and to think critically is a national goal (Educate to Innovate campaign). Despite the best intentions, many students struggle to achieve a basic level of science knowledge (NAEP, 2011). The present study examined Talk Aloud Pair Problem Solving and frequency building with five students who were diagnosed with a disability and receive specialized reading instruction in a special education setting. Acquisition was obtained through scripted lessons and frequency building or practice strengthened the student's verbal repertoire making the problem solving process a durable behavior. Overall, students all demonstrated improvements in problem solving performance when compared to baseline. Students became more significantly accurate in performance and maintenance in learning was demonstrated. Generalization probes indicated improvement in student performance. Implications for practice and future research are discussed.

  13. Polyanthraquinone-Based Organic Cathode for High-Performance Rechargeable Magnesium-Ion Batteries

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

    Pan, Baofei; Huang, Jinhua; Feng, Zhenxing

    2016-05-09

    Two anthraquinone-based polymers aiming at improving the capacity and voltage of magnesium ion batteries, were synthesized and characterized. The excellent battery cycling performance was demonstrated with the electrolyte consisting of magnesium bis(hexamethyldisilazide) and magnesium chloride.

  14. Palmprint authentication using multiple classifiers

    NASA Astrophysics Data System (ADS)

    Kumar, Ajay; Zhang, David

    2004-08-01

    This paper investigates the performance improvement for palmprint authentication using multiple classifiers. The proposed methods on personal authentication using palmprints can be divided into three categories; appearance- , line -, and texture-based. A combination of these approaches can be used to achieve higher performance. We propose to simultaneously extract palmprint features from PCA, Line detectors and Gabor-filters and combine their corresponding matching scores. This paper also investigates the comparative performance of simple combination rules and the hybrid fusion strategy to achieve performance improvement. Our experimental results on the database of 100 users demonstrate the usefulness of such approach over those based on individual classifiers.

  15. Evidence of the preferential use of disease prototypes over case exemplars among early year one medical students prior to and following diagnostic training.

    PubMed

    Papa, Frank J; Li, Feiming

    2015-12-01

    Two core dual processing theory (DPT) System I constructs (Exemplars and Prototypes) were used to: 1) formulate a training exercise designed to improve diagnostic performance in year one medical students, and 2) explore whether any observed performance improvements were associated with preferential use of exemplars or prototypes. With IRB approval, 117 year one medical students participated in an acute chest pain diagnostic training exercise. A pre- and post-training test containing the same 27 case vignettes was used to determine if the subjects' diagnostic performance improved via training in both exemplars and prototypes. Exemplar and Prototype theory was also used to generate a unique typicality estimate for each case vignette. Because these estimates produce different performance predictions, differences in the subjects' observed performance would make it possible to infer whether subjects were preferentially using Exemplars or Prototypes. Pre- vs. post-training comparison revealed a significant performance improvement; t=14.04, p<0.001, Cohen's d=1.32. Pre-training, paired t-testing demonstrated that performance against the most typical vignettes>mid typical vignettes: t=4.94, p<0.001; and mid typical>least typical: t=5.16, p<0.001. Post-training, paired t-testing again demonstrated that performance against the most typical vignettes>mid typical: t=2.94, p<0.01; and mid typical>least typical: t=6.64, p<0.001. These findings are more consistent with the performance predictions generated via Prototype theory than Exemplar theory. DPT is useful in designing and evaluating the utility of new approaches to diagnostic training, and, investigating the cognitive factors driving diagnostic capabilities among early medical students.

  16. On improving the performance of nonphotochemical quenching in CP29 light-harvesting antenna complex

    DOE PAGES

    Berman, Gennady Petrovich; Nesterov, Alexander I.; Sayre, Richard Thomas; ...

    2016-02-02

    In this study, we model and simulate the performance of charge-transfer in nonphotochemical quenching (NPQ) in the CP29 light-harvesting antenna-complex associated with photosystem II (PSII). The model consists of five discrete excitonic energy states and two sinks, responsible for the potentially damaging processes and charge-transfer channels, respectively. We demonstrate that by varying (i) the parameters of the chlorophyll-based dimer, (ii) the resonant properties of the protein-solvent environment interaction, and (iii) the energy transfer rates to the sinks, one can significantly improve the performance of the NPQ. In conclusion, our analysis suggests strategies for improving the performance of the NPQ inmore » response to environmental changes, and may stimulate experimental verification.« less

  17. Improving Science Education through Accountability Relationships in Schools.

    ERIC Educational Resources Information Center

    Wildy, Helen; Wallace, John

    1997-01-01

    Presents a contrast between bureaucratic and professional models of accountability and their impact on the science education enterprise. Topics include improving performance, climate of trust, principles and consequences, demonstrating acceptance of responsibilities, and feedback. Concludes that it is necessary to develop the skills and processes…

  18. Status of nickel/zinc and nickel/iron battery technology for electric vehicle applications

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

    Yao, N.P.; Christianson, C.C.; Elliott, R.C.

    1980-01-01

    Significant progress in nickel/zinc and nickel/iron technology has been made towards achieving the battery technical performance goals necessary for widespread use of these battery systems in electric vehicle applications. This progress is reviewed. Nickel/zinc module test data have shown a specific energy of nearly 70 Whr/kg and a specific power of 130 W/kg. However, cycle life improvements are still needed (presently demonstrated capability of 120 cycles) and are expected to be demonstrated during 1980. Nickel/iron modules have demonstrated a specific energy of nearly 50 Wh/kg and a specific power of 100 W/kg. Indications are that improved performance in these areasmore » can be shown during 1980. Nickel/iron modules cycle lives of 300 have been achieved during early 1980 and testing continues. Energy efficiency has been improved from less than 50% to over 65%. Cost reduction (both initial and operating) continues to receive major emphasis at developers of both nickel/zinc and nickel/iron batteries in order to achieve the lowest possible life cycle cost to the battery user.« less

  19. Exhaust emission reduction for intermittent combustion aircraft engines

    NASA Technical Reports Server (NTRS)

    Moffett, R. N.

    1979-01-01

    Three concepts for optimizing the performance, increasing the fuel economy, and reducing exhaust emission of the piston aircraft engine were investigated. High energy-multiple spark discharge and spark plug tip penetration, ultrasonic fuel vaporization, and variable valve timing were evaluated individually. Ultrasonic fuel vaporization did not demonstrate sufficient improvement in distribution to offset the performance loss caused by the additional manifold restriction. High energy ignition and revised spark plug tip location provided no change in performance or emissions. Variable valve timing provided some performance benefit; however, even greater performance improvement was obtained through induction system tuning which could be accomplished with far less complexity.

  20. Performance Templates and the Regulation of Learning

    ERIC Educational Resources Information Center

    Lyons, Paul

    2009-01-01

    Purpose: The purpose of this paper is to provide a detailed, theoretical underpinning for the training and performance improvement method: performance template (P-T). The efficacy of P-T, with limitations, has been demonstrated in this journal and in others. However, the theoretical bases of the P-T approach had not been well-developed. The other…

  1. Change in Action: Using Positive Deviance to Improve Student Clinical Performance

    ERIC Educational Resources Information Center

    Zaidi, Zareen; Jaffery, Tara; Shahid, Afshan; Moin, Shaheen; Gilani, Ahsen; Burdick, William

    2012-01-01

    At our medical college many students have lower ratings in their clinical performance once they start their clinical years (third year). This is contrary to their results in other written exams. Some students demonstrate better clinical performance. We used the six-step Positive Deviance (PD) Conceptual Framework to identify and disseminate the…

  2. Improved performance of Pseudomonas putida in a bioelectrochemical system through overexpression of periplasmic glucose dehydrogenase.

    PubMed

    Yu, Shiqin; Lai, Bin; Plan, Manuel R; Hodson, Mark P; Lestari, Endah A; Song, Hao; Krömer, Jens O

    2018-01-01

    It was recently demonstrated that a bioelectrochemical system (BES) with a redox mediator allowed Pseudomonas putida to perform anoxic metabolism, converting sugar to sugar acids with high yield. However, the low productivity currently limits the application of this technology. To improve productivity, the strain was optimized through improved expression of glucose dehydrogenase (GCD) and gluconate dehydrogenase (GAD). In addition, quantitative real-time RT-PCR analysis revealed the intrinsic self-regulation of GCD and GAD. Utilizing this self-regulation system, the single overexpression strain (GCD) gave an outstanding performance in the electron transfer rate and 2-ketogluconic acid (2KGA) productivity. The peak anodic current density, specific glucose uptake rate and 2KGA producing rate were 0.12 mA/cm 2 , 0.27 ± 0.02 mmol/g CDW /hr and 0.25 ± 0.02 mmol/g CDW /hr, which were 327%, 477%, and 644% of the values of wild-type P. putida KT2440, respectively. This work demonstrates that expression of periplasmic dehydrogenases involved in electron transfer can significantly improve productivity in the BES. © 2017 Wiley Periodicals, Inc.

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

    Im, Piljae; Liu, Xiaobing

    High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects, a ground-source variable refrigerant flow (GS-VRF) system installed at the Human Health Building at Oakland University in Rochester, Michigan.more » This case study is based on the analysis of measured performance data, maintenance records, construction costs, and simulations of the energy consumption of conventional central heating, ventilation, and air-conditioning (HVAC) systems providing the same level of space conditioning as the demonstrated GS-VRF system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GS-VRF system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the GS-VRF system compared with conventional HVAC systems. This case study also identified opportunities for reducing uncertainties in the performance evaluation, improving the operational efficiency, and reducing the installed cost of similar GSHP systems in the future.« less

  4. Hysteresis modeling of magnetic shape memory alloy actuator based on Krasnosel'skii-Pokrovskii model.

    PubMed

    Zhou, Miaolei; Wang, Shoubin; Gao, Wei

    2013-01-01

    As a new type of intelligent material, magnetically shape memory alloy (MSMA) has a good performance in its applications in the actuator manufacturing. Compared with traditional actuators, MSMA actuator has the advantages as fast response and large deformation; however, the hysteresis nonlinearity of the MSMA actuator restricts its further improving of control precision. In this paper, an improved Krasnosel'skii-Pokrovskii (KP) model is used to establish the hysteresis model of MSMA actuator. To identify the weighting parameters of the KP operators, an improved gradient correction algorithm and a variable step-size recursive least square estimation algorithm are proposed in this paper. In order to demonstrate the validity of the proposed modeling approach, simulation experiments are performed, simulations with improved gradient correction algorithm and variable step-size recursive least square estimation algorithm are studied, respectively. Simulation results of both identification algorithms demonstrate that the proposed modeling approach in this paper can establish an effective and accurate hysteresis model for MSMA actuator, and it provides a foundation for improving the control precision of MSMA actuator.

  5. Large area silicon sheet by EFG

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Progress was made in improving ribbon flatness and reducing stress, and in raising cell performance for 10 cm wide ribbon grown in single cartridge EFG furnaces. Optimization of growth conditions resulted in improved ribbon thickness uniformity at a thickness of 200 micron, grown at 4 cm/minute, and growth at this target speed is routinely achieved over periods of the order of one hour or more. With the improved ribbon flatness, fabrication of large area (50 cm2) cells is now possible, and 10 to 11% efficiencies were demonstrated on ribbon grown at 3.5 to 4 cm/minute. Factors limiting performance of the existing multiple ribbon furnace were identified, and growth system improvements implemented to help raise throughput rates and the time percentage of simultaneous three-ribbon growth. However, it is evident that major redesign of this furnace would be needed to overcome shortfalls in its ability to achieve the Technical Features Demonstration goals of 1980. It was decided to start construction of a new multiple ribbon furnace and to incorporate the desired improvements into its design. The construction of this furnace is completed.

  6. Hysteresis Modeling of Magnetic Shape Memory Alloy Actuator Based on Krasnosel'skii-Pokrovskii Model

    PubMed Central

    Wang, Shoubin; Gao, Wei

    2013-01-01

    As a new type of intelligent material, magnetically shape memory alloy (MSMA) has a good performance in its applications in the actuator manufacturing. Compared with traditional actuators, MSMA actuator has the advantages as fast response and large deformation; however, the hysteresis nonlinearity of the MSMA actuator restricts its further improving of control precision. In this paper, an improved Krasnosel'skii-Pokrovskii (KP) model is used to establish the hysteresis model of MSMA actuator. To identify the weighting parameters of the KP operators, an improved gradient correction algorithm and a variable step-size recursive least square estimation algorithm are proposed in this paper. In order to demonstrate the validity of the proposed modeling approach, simulation experiments are performed, simulations with improved gradient correction algorithm and variable step-size recursive least square estimation algorithm are studied, respectively. Simulation results of both identification algorithms demonstrate that the proposed modeling approach in this paper can establish an effective and accurate hysteresis model for MSMA actuator, and it provides a foundation for improving the control precision of MSMA actuator. PMID:23737730

  7. Improvement in interfacial characteristics of low-voltage carbon nanotube thin-film transistors with solution-processed boron nitride thin films

    NASA Astrophysics Data System (ADS)

    Jeon, Jun-Young; Ha, Tae-Jun

    2017-08-01

    In this article, we demonstrate the potential of solution-processed boron nitride (BN) thin films for high performance single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) with low-voltage operation. The use of BN thin films between solution-processed high-k dielectric layers improved the interfacial characteristics of metal-insulator-metal devices, thereby reducing the current density by three orders of magnitude. We also investigated the origin of improved device performance in SWCNT-TFTs by employing solution-processed BN thin films as an encapsulation layer. The BN encapsulation layer improves the electrical characteristics of SWCNT-TFTs, which includes the device key metrics of linear field-effect mobility, sub-threshold swing, and threshold voltage as well as the long-term stability against the aging effect in air. Such improvements can be achieved by reduced interaction of interfacial localized states with charge carriers. We believe that this work can open up a promising route to demonstrate the potential of solution-processed BN thin films on nanoelectronics.

  8. Improved Cognition While Cycling in Parkinson’s Disease Patients and Healthy Adults

    PubMed Central

    Hazamy, Audrey A.; Altmann, Lori J. P.; Stegemöller, Elizabeth; Bowers, Dawn; Lee, Hyo Keun; Wilson, Jonathan; Okun, Michael S.; Hass, Chris J.

    2017-01-01

    Persons with Parkinson’s disease (PD) are typically more susceptible than healthy adults to impaired performance when two tasks (dual task interference) are performed simultaneously. This limitation has by many experts been attributed to limitations in cognitive resources. Nearly all studies of dual task performance in PD employ walking or balance-based motor tasks, which are commonly impaired in PD. These tasks can be performed using a combination of one or two executive function tasks. The current study examined whether persons with PD would demonstrate greater dual task effects on cognition compared to healthy older adults (HOAs) during a concurrent cycling task. Participants with and without PD completed a battery of 12 cognitive tasks assessing visual and verbal processing in the following cognitive domains: speed of processing, controlled processing, working memory and executive function. Persons with PD exhibited impairments compared to healthy participants in select tasks (i.e., 0-Back, 2-Back and operation span). Further, both groups unexpectedly exhibited dual task facilitation of response times in visual tasks across cognitive domains, and improved verbal recall during an executive function task. Only one measure, 2-back, showed a speed-accuracy trade-off in the dual task. These results demonstrate that, when paired with a motor task in which they are not impaired, people with PD exhibit similar dual task effects on cognitive tasks as HOAs, even when these dual task effects are facilitative. More generally, these findings demonstrate that pairing cognitive tasks with cycling may actually improve cognitive performance which may have therapeutic relevance to cognitive decline associated with aging and PD pathology. PMID:28088064

  9. Green Roofs

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

    None

    A New Technology Demonstration Publication Green roofs can improve the energy performance of federal buildings, help manage stormwater, reduce airborne emissions, and mitigate the effects of urban heat islands.

  10. Engine component improvement: Performance improvement, JT9D-7 3.8 AR fan

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1980-01-01

    A redesigned, fuel efficient fan for the JT9D-7 engine was tested. Tests were conducted to determine the effect of the 3.8 AR fan on performance, stability, operational characteristics, and noise of the JT9D-7 engine relative to the current 4.6 AR Bill-of-Material fan. The 3.8 AR fan provides increased fan efficiency due to a more advanced blade airfoil with increased chord, eliminating one part span shroud and reducing the number of fan blades and fan exit guide vanes. Engine testing at simulated cruise conditions demonstrated the predicted 1.3 percent improvement in specific fuel consumption with the redesigned 3.8 AR fan. Flight testing and sea level stand engine testing demonstrated exhaust gas temperature margins, fan and low pressure compressor stability, operational suitability, and noise levels comparable to the Bill-of-Material fan.

  11. Effects of Elastic Resistance Exercise on Muscle Strength and Functional Performance in Healthy Adults: A Systematic Review and Meta-Analysis.

    PubMed

    de Oliveira, Poliana Alves; Blasczyk, Juscelino Castro; Souza Junior, Gerson; Lagoa, Karina Ferreira; Soares, Milene; de Oliveira, Ricardo Jacó; Filho, Paulo José Barbosa Gutierres; Carregaro, Rodrigo Luiz; Martins, Wagner Rodrigues

    2017-04-01

    Elastic Resistance Exercise (ERE) has already demonstrated its effectiveness in older adults and, when combined with the resistance generated by fixed loads, in adults. This review summarizes the effectiveness of ERE performed as isolated method on muscle strength and functional performance in healthy adults. A database search was performed (MEDLine, Cochrane Library, PEDro and Web of Knowledge) to identify controlled clinical trials in English language. The mean difference (MD) with 95% confidence intervals (CIs) and overall effect size were calculated for all comparisons. The PEDro scale was used assess the methodological quality. From the 93 articles identified by the search strategy, 5 met the inclusion criteria, in which 3 presented high quality (PEDro > 6). Meta-analyses demonstrated that the effects of ERE were superior when compared with passive control on functional performance and muscle strength. When compared with active controls, the effect of ERE was inferior on function performance and with similar effect on muscle strength. ERE are effective to improve functional performance and muscle strength when compared with no intervention, in healthy adults. ERE are not superior to other methods of resistance training to improve functional performance and muscle strength in health adults.

  12. Improvement in motor performance of Weaver mutant mice following lesions of the cerebellum.

    PubMed

    Grüsser, C; Grüsser-Cornehls, U

    1998-12-01

    In Weaver mutants (B6CBA wv/wv) cerebellar granule cells degenerate almost completely postnatally. A partial loss of Purkinje cells (PC) and a degeneration of dopaminergic cells in the substantia nigra have also been found. Weaver mice suffer from striking motor symptoms, including difficulty in walking without toppling over. In an attempt to influence the poor motor performance, the cerebellum in young animals was removed, thus eliminating the faulty output of surviving PCs, demonstrated electrophysiologically. Unoperated Weaver, lesioned wildtypes and one sham mouse were used as controls. Before and after operation, a battery of behavioural tests was performed. In Weaver mice, tumbling to the side (t) and the relation of t to the motor activity (k) while traversing an open-field matrix, (t/k), improved considerably, as did manoeuvring on a slanted wire mesh, but keeping balance on a wooden bench did not to the same degree. Locomotor activity alone improved in some animals. In wildtypes no significant changes occurred after operation, with the exception of a strong reduction in locomotor activity. The experiments demonstrate that the motor performance in Weaver mutant mice benefits from removal of their cerebellum.

  13. Wisconsin K-12 Career Education Consortium. Final Project Performance Report. Volume I of Two Volumes.

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Public Instruction, Madison.

    To demonstrate career education methods and procedures, seven Wisconsin school districts were chosen to participate in an incremental improvement project. Project activities were conducted district-wide and by individual districts. District-wide dissemination activities involved promoting demonstration packets and assessment/evaluation (AE)…

  14. Does virtual reality simulation have a role in training trauma and orthopaedic surgeons?

    PubMed

    Bartlett, J D; Lawrence, J E; Stewart, M E; Nakano, N; Khanduja, V

    2018-05-01

    Aims The aim of this study was to assess the current evidence relating to the benefits of virtual reality (VR) simulation in orthopaedic surgical training, and to identify areas of future research. Materials and Methods A literature search using the MEDLINE, Embase, and Google Scholar databases was performed. The results' titles, abstracts, and references were examined for relevance. Results A total of 31 articles published between 2004 and 2016 and relating to the objective validity and efficacy of specific virtual reality orthopaedic surgical simulators were identified. We found 18 studies demonstrating the construct validity of 16 different orthopaedic virtual reality simulators by comparing expert and novice performance. Eight studies have demonstrated skill acquisition on a simulator by showing improvements in performance with repeated use. A further five studies have demonstrated measurable improvements in operating theatre performance following a period of virtual reality simulator training. Conclusion The demonstration of 'real-world' benefits from the use of VR simulation in knee and shoulder arthroscopy is promising. However, evidence supporting its utility in other forms of orthopaedic surgery is lacking. Further studies of validity and utility should be combined with robust analyses of the cost efficiency of validated simulators to justify the financial investment required for their use in orthopaedic training. Cite this article: Bone Joint J 2018;100-B:559-65.

  15. Rule-Based Category Learning in Children: The Role of Age and Executive Functioning

    PubMed Central

    Rabi, Rahel; Minda, John Paul

    2014-01-01

    Rule-based category learning was examined in 4–11 year-olds and adults. Participants were asked to learn a set of novel perceptual categories in a classification learning task. Categorization performance improved with age, with younger children showing the strongest rule-based deficit relative to older children and adults. Model-based analyses provided insight regarding the type of strategy being used to solve the categorization task, demonstrating that the use of the task appropriate strategy increased with age. When children and adults who identified the correct categorization rule were compared, the performance deficit was no longer evident. Executive functions were also measured. While both working memory and inhibitory control were related to rule-based categorization and improved with age, working memory specifically was found to marginally mediate the age-related improvements in categorization. When analyses focused only on the sample of children, results showed that working memory ability and inhibitory control were associated with categorization performance and strategy use. The current findings track changes in categorization performance across childhood, demonstrating at which points performance begins to mature and resemble that of adults. Additionally, findings highlight the potential role that working memory and inhibitory control may play in rule-based category learning. PMID:24489658

  16. Bingo! Externally-Supported Performance Intervention for Deficient Visual Search in Normal Aging, Parkinson’s Disease and Alzheimer’s Disease

    PubMed Central

    Laudate, Thomas M.; Neargarder, Sandy; Dunne, Tracy E.; Sullivan, Karen D.; Joshi, Pallavi; Gilmore, Grover C.; Riedel, Tatiana M.; Cronin-Golomb, Alice

    2011-01-01

    External support may improve task performance regardless of an individual’s ability to compensate for cognitive deficits through internally-generated mechanisms. We investigated if performance of a complex, familiar visual search task (the game of bingo) could be enhanced in groups with suboptimal vision by providing external support through manipulation of task stimuli. Participants were 19 younger adults, 14 individuals with probable Alzheimer’s disease (AD), 13 AD-matched healthy adults, 17 non-demented individuals with Parkinson’s disease (PD), and 20 PD-matched healthy adults. We varied stimulus contrast, size, and visual complexity during game play. The externally-supported performance interventions of increased stimulus size and decreased complexity resulted in improvements in performance by all groups. Performance improvement through increased stimulus size and decreased complexity was demonstrated by all groups. AD also obtained benefit from increasing contrast, presumably by compensating for their contrast sensitivity deficit. The general finding of improved performance across healthy and afflicted groups suggests the value of visual support as an easy-to-apply intervention to enhance cognitive performance. PMID:22066941

  17. Satellite Communications for Aeronautics Applications: Technology Development and Demonstration

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Hoder, Douglas J.; Zakrajsek, Robert J.

    2001-01-01

    The National Aeronautics and Space Administration (NASA) is performing research and development to improve the safety and increase the capacity of the National Airspace System (NAS). Improved communications, especially to and from the aircraft flight deck, has been identified as an essential enabling technology for future improvements to the air traffic management system and aviation safety. NASA's Glenn Research Center is engaged in research and development of satellite communications technologies for aeronautical applications. A mobile aero terminal has been developed for use with Ku band commercial communications satellites. This experimental terminal will be used in mobile ground and air-based tests and demonstrations during 2000-2004. This paper will describe the basic operational parameters of the Ku Band aero terminal, the communications architecture it is intended to demonstrate, and the key technology issues being addressed in the tests and demonstrations. The design of the Ku Band aero terminal and associated ground testbed, planned tests and demonstrations, and results to date will be presented.

  18. Advanced techniques for determining long term compatibility of materials with propellants

    NASA Technical Reports Server (NTRS)

    Green, R. L.

    1972-01-01

    The search for advanced measurement techniques for determining long term compatibility of materials with propellants was conducted in several parts. A comprehensive survey of the existing measurement and testing technology for determining material-propellant interactions was performed. Selections were made from those existing techniques which were determined could meet or be made to meet the requirements. Areas of refinement or changes were recommended for improvement of others. Investigations were also performed to determine the feasibility and advantages of developing and using new techniques to achieve significant improvements over existing ones. The most interesting demonstration was that of the new technique, the volatile metal chelate analysis. Rivaling the neutron activation analysis in terms of sensitivity and specificity, the volatile metal chelate technique was fully demonstrated.

  19. The effect of normal aging and age-related macular degeneration on perceptual learning.

    PubMed

    Astle, Andrew T; Blighe, Alan J; Webb, Ben S; McGraw, Paul V

    2015-01-01

    We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach.

  20. The effect of normal aging and age-related macular degeneration on perceptual learning

    PubMed Central

    Astle, Andrew T.; Blighe, Alan J.; Webb, Ben S.; McGraw, Paul V.

    2015-01-01

    We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach. PMID:26605694

  1. Reorganization of functional brain networks mediates the improvement of cognitive performance following real-time neurofeedback training of working memory.

    PubMed

    Zhang, Gaoyan; Yao, Li; Shen, Jiahui; Yang, Yihong; Zhao, Xiaojie

    2015-05-01

    Working memory (WM) is essential for individuals' cognitive functions. Neuroimaging studies indicated that WM fundamentally relied on a frontoparietal working memory network (WMN) and a cinguloparietal default mode network (DMN). Behavioral training studies demonstrated that the two networks can be modulated by WM training. Different from the behavioral training, our recent study used a real-time functional MRI (rtfMRI)-based neurofeedback method to conduct WM training, demonstrating that WM performance can be significantly improved after successfully upregulating the activity of the target region of interest (ROI) in the left dorsolateral prefrontal cortex (Zhang et al., [2013]: PloS One 8:e73735); however, the neural substrate of rtfMRI-based WM training remains unclear. In this work, we assessed the intranetwork and internetwork connectivity changes of WMN and DMN during the training, and their correlations with the change of brain activity in the target ROI as well as with the improvement of post-training behavior. Our analysis revealed an "ROI-network-behavior" correlation relationship underlying the rtfMRI training. Further mediation analysis indicated that the reorganization of functional brain networks mediated the effect of self-regulation of the target brain activity on the improvement of cognitive performance following the neurofeedback training. The results of this study enhance our understanding of the neural basis of real-time neurofeedback and suggest a new direction to improve WM performance by regulating the functional connectivity in the WM related networks. © 2014 Wiley Periodicals, Inc.

  2. 34 CFR 645.32 - How does the Secretary evaluate prior experience?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... performance under its expiring Upward Bound grant. This information includes information derived from annual performance reports, audit reports, site visit reports, project evaluation reports, and any other verifiable... project participants have demonstrated improvement in academic skills and competencies as measured by...

  3. Learning to re-appraise the self during video feedback for social anxiety: Does depth of processing matter?

    PubMed

    Orr, Elizabeth M J; Moscovitch, David A

    2010-08-01

    Video feedback (VF) with cognitive preparation (CP) has been widely integrated into cognitive-behavioral therapy (CBT) protocols for social anxiety disorder (SAD) due to its presumed efficacy in improving negative self-perception. However, previous experimental studies have demonstrated that improvements in negative self-perception via VF+CP do not typically facilitate anxiety reduction during subsequent social interactions - a troubling finding for proponents of cognitive models of social anxiety. We examined whether VF+CP could be optimized to enhance participants' processing of corrective self-related information through the addition of a post-VF cognitive review (CR). Sixty-eight socially anxious individuals were randomly assigned to perform two public speeches in one of the following conditions: a) exposure alone (EXP); b) CP+VF; and c) CP+VF+CR. Those in the CP+VF+CR condition demonstrated marginally significant reductions in anxiety from speech 1 to speech 2 relative to those who received EXP - an improvement not shown for those in the CP+VF condition. Furthermore, only those who received CP+VF+CR demonstrated significant improvements in self-perception and performance expectations relative to EXP. Decreases in anxiety among participants who received CP+VF+CR relative to EXP were fully mediated by improvements in self-perception. Implications are discussed in the context of cognitive models of social anxiety and mechanisms of exposure-based learning. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Comfort-oriented vehicle suspension design with skyhook inerter configuration

    NASA Astrophysics Data System (ADS)

    Hu, Yinlong; Chen, Michael Z. Q.; Sun, Yonghui

    2017-09-01

    This paper is concerned with the comfort-oriented vehicle suspension design problem by using a skyhook inerter configuration. The rationale of the skyhook inerter is to use a grounded inerter to virtually increase the sprung mass of a vehicle, as it is analytically demonstrated that increasing the sprung mass can always improve the ride comfort performance. Semi-active means to realize the skyhook inerter configuration are investigated by using semi-active inerters. Three control laws, that is the on-off control, the anti-chatter on-off control, and the continuous control, are proposed for the semi-active inerter to approximate the skyhook inerter. Numerical simulations are performed to demonstrate the effectiveness and performances of these control laws. It is shown that the semi-active realizations of the skyhook inerter by using the proposed control laws can achieve over 10% improvement compared with the traditional strut, and similar performances are obtained for these control laws, with slight differences with respect to different static stiffnesses of the suspension system.

  5. The Application of Observational Practice and Educational Networking in Simulation-Based and Distributed Medical Education Contexts.

    PubMed

    Welsher, Arthur; Rojas, David; Khan, Zain; VanderBeek, Laura; Kapralos, Bill; Grierson, Lawrence E M

    2018-02-01

    Research has revealed that individuals can improve technical skill performance by viewing demonstrations modeled by either expert or novice performers. These findings support the development of video-based observational practice communities that augment simulation-based skill education and connect geographically distributed learners. This study explores the experimental replicability of the observational learning effect when demonstrations are sampled from a community of distributed learners and serves as a context for understanding learner experiences within this type of training protocol. Participants from 3 distributed medical campuses engaged in a simulation-based learning study of the elliptical excision in which they completed a video-recorded performance before being assigned to 1 of 3 groups for a 2-week observational practice intervention. One group observed expert demonstrations, another observed novice demonstrations, and the third observed a combination of both. Participants returned for posttesting immediately and 1 month after the intervention. Participants also engaged in interviews regarding their perceptions of the usability and relevance of video-based observational practice to clinical education. Checklist (P < 0.0001) and global rating (P < 0.0001) measures indicate that participants, regardless of group assignment, improved after the intervention and after a 1-month retention period. Analyses revealed no significant differences between groups. Qualitative analyses indicate that participants perceived the observational practice platform to be usable, relevant, and potentially improved with enhanced feedback delivery. Video-based observational practice involving expert and/or novice demonstrations enhances simulation-based skill learning in a group of geographically distributed trainees. These findings support the use of Internet-mediated observational learning communities in distributed and simulation-based medical education contexts.

  6. Construction of Uniform Cobalt-Based Nanoshells and Its Potential for Improving Li-Ion Battery Performance.

    PubMed

    Piao, Jun-Yu; Liu, Xiao-Chan; Wu, Jinpeng; Yang, Wanli; Wei, Zengxi; Ma, Jianmin; Duan, Shu-Yi; Lin, Xi-Jie; Xu, Yan-Song; Cao, An-Min; Wan, Li-Jun

    2018-06-28

    Surface cobalt doping is an effective and economic way to improve the electrochemical performance of cathode materials. Herein, by tuning the precipitation kinetics of Co 2+ , we demonstrate an aqueous-based protocol to grow uniform basic cobaltous carbonate coating layer onto different substrates, and the thickness of the coating layer can be adjusted precisely in nanometer accuracy. Accordingly, by sintering the cobalt-coated LiNi 0.5 Mn 1.5 O 4 cathode materials, an epitaxial cobalt-doped surface layer will be formed, which will act as a protective layer without hindering charge transfer. Consequently, improved battery performance is obtained because of the suppression of interfacial degradation.

  7. Performance enhancement of pentacene-based organic thin-film transistors using 6,13-pentacenequinone as a carrier injection interlayer

    NASA Astrophysics Data System (ADS)

    Fan, Ching-Lin; Lin, Wei-Chun; Chen, Hao-Wei

    2018-06-01

    This work demonstrates pentacene-based organic thin-film transistors (OTFTs) fabricated by inserting a 6,13-pentacenequinone (PQ) carrier injection layer between the source/drain (S/D) metal Au electrodes and pentacene channel layer. Compared to devices without a PQ layer, the performance characteristics including field-effect mobility, threshold voltage, and On/Off current ratio were significantly improved for the device with a 5-nm-thick PQ interlayer. These improvements are attributed to significant reduction of hole barrier height at the Au/pentacene channel interfaces. Therefore, it is believed that using PQ as the carrier injection layer is a good candidate to improve the pentacene-based OTFTs electrical performance.

  8. Enhanced Control of Attention by Stimulating Mesolimbic-Corticopetal Cholinergic Circuitry

    PubMed Central

    St. Peters, Megan; Demeter, Elise; Lustig, Cindy; Bruno, John P.; Sarter, Martin

    2011-01-01

    Sustaining and recovering attentional performance requires interactions between the brain’s motivation and attention systems. The first experiment demonstrated that in rats performing a sustained attention task (SAT), presentation of a distractor (dSAT) augmented performance-associated increases in cholinergic neurotransmission in prefrontal cortex (PFC). Because stimulation of NMDA receptors in the shell of the nucleus accumbens (NAC) activates PFC cholinergic neurotransmission, a second experiment demonstrated that bilateral infusions of NMDA into the NAC shell, but not core, improved dSAT-performance to levels observed in the absence of a distractor. A third experiment demonstrated that removal of prefrontal or posterior parietal cholinergic inputs, by intra-cortical infusions of the cholinotoxin 192 IgG saporin, attenuated the beneficial effects of NMDA on dSAT perfomance. Mesolimbic activation of cholinergic projections to the cortex benefits the cognitive control of attentional performance by enhancing the detection of cues and the filtering of distractors. PMID:21715641

  9. Development of an Enhanced Payback Function for the Superior Energy Performance Program

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

    Therkelsen, Peter; Rao, Prakash; McKane, Aimee

    2015-08-03

    The U.S. DOE Superior Energy Performance (SEP) program provides recognition to industrial and commercial facilities that achieve certification to the ISO 50001 energy management system standard and third party verification of energy performance improvements. Over 50 industrial facilities are participating and 28 facilities have been certified in the SEP program. These facilities find value in the robust, data driven energy performance improvement result that the SEP program delivers. Previous analysis of SEP certified facility data demonstrated the cost effectiveness of SEP and identified internal staff time to be the largest cost component related to SEP implementation and certification. This papermore » analyzes previously reported and newly collected data of costs and benefits associated with the implementation of an ISO 50001 and SEP certification. By disaggregating “sunk energy management system (EnMS) labor costs”, this analysis results in a more accurate and detailed understanding of the costs and benefits of SEP participation. SEP is shown to significantly improve and sustain energy performance and energy cost savings, resulting in a highly attractive return on investment. To illustrate these results, a payback function has been developed and is presented. On average facilities with annual energy spend greater than $2M can expect to implement SEP with a payback of less than 1.5 years. Finally, this paper also observes and details decreasing facility costs associated with implementing ISO 50001 and certifying to the SEP program, as the program has improved from pilot, to demonstration, to full launch.« less

  10. Implementing a Parallel Image Edge Detection Algorithm Based on the Otsu-Canny Operator on the Hadoop Platform.

    PubMed

    Cao, Jianfang; Chen, Lichao; Wang, Min; Tian, Yun

    2018-01-01

    The Canny operator is widely used to detect edges in images. However, as the size of the image dataset increases, the edge detection performance of the Canny operator decreases and its runtime becomes excessive. To improve the runtime and edge detection performance of the Canny operator, in this paper, we propose a parallel design and implementation for an Otsu-optimized Canny operator using a MapReduce parallel programming model that runs on the Hadoop platform. The Otsu algorithm is used to optimize the Canny operator's dual threshold and improve the edge detection performance, while the MapReduce parallel programming model facilitates parallel processing for the Canny operator to solve the processing speed and communication cost problems that occur when the Canny edge detection algorithm is applied to big data. For the experiments, we constructed datasets of different scales from the Pascal VOC2012 image database. The proposed parallel Otsu-Canny edge detection algorithm performs better than other traditional edge detection algorithms. The parallel approach reduced the running time by approximately 67.2% on a Hadoop cluster architecture consisting of 5 nodes with a dataset of 60,000 images. Overall, our approach system speeds up the system by approximately 3.4 times when processing large-scale datasets, which demonstrates the obvious superiority of our method. The proposed algorithm in this study demonstrates both better edge detection performance and improved time performance.

  11. Performance analysis and improvement of WPAN MAC for home networks.

    PubMed

    Mehta, Saurabh; Kwak, Kyung Sup

    2010-01-01

    The wireless personal area network (WPAN) is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC) is proposed to coordinate the access to the wireless medium among the competing devices, especially for short range and high data rate applications in home networks. In this paper we use analytical modeling to study the performance analysis of WPAN (IEEE 802.15.3) MAC in terms of throughput, efficient bandwidth utilization, and delay with various ACK policies under error channel condition. This allows us to introduce a K-Dly-ACK-AGG policy, payload size adjustment mechanism, and Improved Backoff algorithm to improve the performance of the WPAN MAC. Performance evaluation results demonstrate the impact of our improvements on network capacity. Moreover, these results can be very useful to WPAN application designers and protocol architects to easily and correctly implement WPAN for home networking.

  12. Flashing characters with famous faces improves ERP-based brain-computer interface performance

    NASA Astrophysics Data System (ADS)

    Kaufmann, T.; Schulz, S. M.; Grünzinger, C.; Kübler, A.

    2011-10-01

    Currently, the event-related potential (ERP)-based spelling device, often referred to as P300-Speller, is the most commonly used brain-computer interface (BCI) for enhancing communication of patients with impaired speech or motor function. Among numerous improvements, a most central feature has received little attention, namely optimizing the stimulus used for eliciting ERPs. Therefore we compared P300-Speller performance with the standard stimulus (flashing characters) against performance with stimuli known for eliciting particularly strong ERPs due to their psychological salience, i.e. flashing familiar faces transparently superimposed on characters. Our results not only indicate remarkably increased ERPs in response to familiar faces but also improved P300-Speller performance due to a significant reduction of stimulus sequences needed for correct character classification. These findings demonstrate a promising new approach for improving the speed and thus fluency of BCI-enhanced communication with the widely used P300-Speller.

  13. Performance Analysis and Improvement of WPAN MAC for Home Networks

    PubMed Central

    Mehta, Saurabh; Kwak, Kyung Sup

    2010-01-01

    The wireless personal area network (WPAN) is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC) is proposed to coordinate the access to the wireless medium among the competing devices, especially for short range and high data rate applications in home networks. In this paper we use analytical modeling to study the performance analysis of WPAN (IEEE 802.15.3) MAC in terms of throughput, efficient bandwidth utilization, and delay with various ACK policies under error channel condition. This allows us to introduce a K-Dly-ACK-AGG policy, payload size adjustment mechanism, and Improved Backoff algorithm to improve the performance of the WPAN MAC. Performance evaluation results demonstrate the impact of our improvements on network capacity. Moreover, these results can be very useful to WPAN application designers and protocol architects to easily and correctly implement WPAN for home networking. PMID:22319274

  14. Publicly reported quality-of-care measures influenced Wisconsin physician groups to improve performance

    PubMed Central

    Lamb, Geoffrey C.; Smith, Maureen; Weeks, William B.; Queram, Christopher

    2014-01-01

    Public reporting of performance on quality measures is increasingly common but little is known about the impact, especially among physician groups. The Wisconsin Collaborative for Healthcare Quality (Collaborative) is a voluntary consortium of physician groups which has publicly reported quality measures since 2004, providing an opportunity to study the effect of this effort on participating groups. Analyses included member performance on 14 ambulatory measures from 2004–2009, a survey regarding reporting and its relationship to improvement efforts, and use of Medicare billing data to independently compare Collaborative members to the rest of Wisconsin, neighboring states and the rest of the United States. Faced with limited resources, groups prioritized their efforts based on the nature of the measure and their performance compared to others. The outcomes demonstrated that public reporting was associated with improvement in health quality and that large physician group practices will engage in improvement efforts in response. PMID:23459733

  15. 76 FR 35864 - Proposed Priority; Special Demonstration Programs-National Technical Assistance Projects To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... have national significance and improve the performance of State vocational rehabilitation (VR) agencies... that State VR agencies and their partners, need national TA opportunities to improve program management and to keep informed about current effective and promising practices and research in the field of VR...

  16. 76 FR 50474 - Special Demonstration Programs-National Technical Assistance Projects To Improve Employment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-15

    ... its vocational rehabilitation (VR) programs. We intend the priority to increase the transfer... the field of rehabilitation that have national significance and to improve the performance of State VR... Technical Assistance and Continuing Education (TACE) centers, and State VR agencies. For example, the...

  17. Increasing Medicaid Revenue Generation for Services by School Psychologists

    ERIC Educational Resources Information Center

    Hybza, Megan M.; Stokes, Trevor F.; Hayman, Marilee; Schatzberg, Tracy

    2013-01-01

    We examined a performance improvement package with components of feedback, goal setting, and prompting to generate additional revenue by improving the consistency of Medicaid billing submitted by 74 school psychologists serving 102 schools. A multiple baseline design across three service areas of a county school system demonstrated the…

  18. Improving Children's Working Memory and Classroom Performance

    ERIC Educational Resources Information Center

    St Clair-Thompson, Helen; Stevens, Ruth; Hunt, Alexandra; Bolder, Emma

    2010-01-01

    Previous research has demonstrated close relationships between working memory and children's scholastic attainment. The aim of the present study was to explore a method of improving working memory, using memory strategy training. Two hundred and fifty-four children aged five to eight years were tested on measures of the phonological loop,…

  19. Attentional Modulation in Visual Cortex Is Modified during Perceptual Learning

    ERIC Educational Resources Information Center

    Bartolucci, Marco; Smith, Andrew T.

    2011-01-01

    Practicing a visual task commonly results in improved performance. Often the improvement does not transfer well to a new retinal location, suggesting that it is mediated by changes occurring in early visual cortex, and indeed neuroimaging and neurophysiological studies both demonstrate that perceptual learning is associated with altered activity…

  20. Traditional Labs + New Questions = Improved Student Performance.

    ERIC Educational Resources Information Center

    Rezba, Richard J.; And Others

    1992-01-01

    Presents three typical lab activities involving the breathing rate of fish, the behavior of electromagnets, and tests for water hardness to demonstrate how labs can be modified to teach process skills. Discusses how basic concepts about experimentation are developed and ways of generating and improving science experiments. Includes a laboratory…

  1. Performance-Based Contracting in Residential Care and Treatment: Driving Policy and Practice Change through Public-Private Partnership in Illinois

    ERIC Educational Resources Information Center

    Kearney, Kathleen A.; McEwen, Erwin; Bloom-Ellis, Brice; Jordan, Neil

    2010-01-01

    The National Quality Improvement Center on the Privatization of Child Welfare Services selected Illinois as a demonstration site in 2007 to evaluate performance-based contracting in residential treatment services. This article discusses the first two years of project implementation including developing residential treatment performance indicators,…

  2. Improved confinement in highly powered high performance scenarios on DIII-D

    NASA Astrophysics Data System (ADS)

    Petrie, T. W.; Osborne, T.; Fenstermacher, M. E.; Ferron, J.; Groebner, R.; Grierson, B.; Holcomb, C.; Lasnier, C.; Leonard, A.; Luce, T.; Makowski, M.; Turco, F.; Solomon, W.; Victor, B.; Watkins, J.

    2017-08-01

    DIII-D has recently demonstrated improved energy confinement by injecting neutral deuterium gas into high performance near-double null divertor (DND) plasmas during high power operation. Representative parameters for these plasmas are: q 95  =  6, P IN up to 15 MW, H 98  =  1.4-1.8, and β N  =  2.5-4.0. The ion B   ×  \

  3. Tuning HDF5 for Lustre File Systems

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

    Howison, Mark; Koziol, Quincey; Knaak, David

    2010-09-24

    HDF5 is a cross-platform parallel I/O library that is used by a wide variety of HPC applications for the flexibility of its hierarchical object-database representation of scientific data. We describe our recent work to optimize the performance of the HDF5 and MPI-IO libraries for the Lustre parallel file system. We selected three different HPC applications to represent the diverse range of I/O requirements, and measured their performance on three different systems to demonstrate the robustness of our optimizations across different file system configurations and to validate our optimization strategy. We demonstrate that the combined optimizations improve HDF5 parallel I/O performancemore » by up to 33 times in some cases running close to the achievable peak performance of the underlying file system and demonstrate scalable performance up to 40,960-way concurrency.« less

  4. Space Shuttle development update

    NASA Technical Reports Server (NTRS)

    Brand, V.

    1984-01-01

    The development efforts, since the STS-4 flight, in the Space Shuttle (SS) program are presented. The SS improvements introduced in the last two years include lower-weight loads, communication through the Tracking and Data Relay Satellite, expanded extravehicular activity capability, a maneuvering backpack and the manipulator foot restraint, the improvements in thermal projection system, the 'optional terminal area management targeting' guidance software, a rendezvous system with radar and star tracker sensors, and improved on-orbit living conditions. The flight demonstrations include advanced launch techniques (e.g., night launch and direct insertion to orbit); the on-orbit demonstrations; and added entry and launching capabilities. The entry aerodynamic analysis and entry flight control fine tuning are described. Reusability, improved ascent performance, intact abort and landing flexibility, rollout control, and 'smart speedbrakes' are among the many improvements planned for the future.

  5. Randomized Controlled Trial Investigating the Role of Exercise in the Workplace to Improve Work Ability, Performance, and Patient-Reported Symptoms Among Older Workers With Osteoarthritis.

    PubMed

    Chopp-Hurley, Jaclyn N; Brenneman, Elora C; Wiebenga, Emily G; Bulbrook, Brittany; Keir, Peter J; Maly, Monica R

    2017-06-01

    The aim of this study was to evaluate the effectiveness of a 12-week workplace exercise program on work ability, performance, and patient-reported symptoms in older university employees with knee and/or hip osteoarthritis. Twenty-four participants with clinical hip and/or knee osteoarthritis were randomized to exercise or no exercise. At baseline and follow-up, several work (work ability, resilience), patient-reported (pain, physical function, depressive symptoms, self-efficacy), and performance outcomes (hip and knee strength, mobility performance) were measured. Significant improvements in work ability (P < 0.049) and patient-reported outcomes (pain, function, depressive symptoms) existed in the exercise group. No improvements were demonstrated in the no exercise group. Exercise in the workplace improved work ability and patient-reported symptoms in older workers with osteoarthritis. The benefits of workplace exercise programs should be studied in a larger sample in which attention is given to improving exercise adherence.

  6. A surgical skills laboratory improves residents' knowledge and performance of episiotomy repair.

    PubMed

    Banks, Erika; Pardanani, Setul; King, Mary; Chudnoff, Scott; Damus, Karla; Freda, Margaret Comerford

    2006-11-01

    This study was undertaken to assess whether a surgical skills laboratory improves residents' knowledge and performance of episiotomy repair. Twenty-four first- and second-year residents were randomly assigned to either a surgical skills laboratory on episiotomy repair or traditional teaching alone. Pre- and posttests assessed basic knowledge. Blinded attending physicians assessed performance, evaluating residents on second-degree laceration/episiotomy repairs in the clinical setting with 3 validated tools: a task-specific checklist, global rating scale, and a pass-fail grade. Postgraduate year 1 (PGY-1) residents participating in the laboratory scored significantly better on all 3 surgical assessment tools: the checklist, the global score, and the pass/fail analysis. All the residents who had the teaching laboratory demonstrated significant improvements on knowledge and the skills checklist. PGY-2 residents did not benefit as much as PGY-1 residents. A surgical skills laboratory improved residents' knowledge and performance in the clinical setting. Improvement was greatest for PGY-1 residents.

  7. Reserve Li/SOC12 Battery Safety Testing

    NASA Technical Reports Server (NTRS)

    Dils, C. T.; Garoutte, K. F.

    1984-01-01

    A reserve Lithium/Thionyl Chloride Battery concept is developed and undergoing feasibility testing in terms of performance, safety and abusive conditions. The feasibility of employing a battery of this type to replace thermal batteries in certain applications is demonstrated. Excellent performance of a Li/SOCl2 reserve battery is obtained across the temperature range from 0 C to +44 C. Performance improvement over the thermal battery usage is greater by a factor of 3 when discharge time and energy density are compared. Performance over an expanded temperature range is also possible. Safety and abusive testing is accomplished successfully on a series of five units. Further performance improvements can be achieved with regard to battery weight and volume reductions.

  8. Testing the Limits of Optimizing Dual-Task Performance in Younger and Older Adults

    PubMed Central

    Strobach, Tilo; Frensch, Peter; Müller, Herrmann Josef; Schubert, Torsten

    2012-01-01

    Impaired dual-task performance in younger and older adults can be improved with practice. Optimal conditions even allow for a (near) elimination of this impairment in younger adults. However, it is unknown whether such (near) elimination is the limit of performance improvements in older adults. The present study tests this limit in older adults under conditions of (a) a high amount of dual-task training and (b) training with simplified component tasks in dual-task situations. The data showed that a high amount of dual-task training in older adults provided no evidence for an improvement of dual-task performance to the optimal dual-task performance level achieved by younger adults. However, training with simplified component tasks in dual-task situations exclusively in older adults provided a similar level of optimal dual-task performance in both age groups. Therefore through applying a testing the limits approach, we demonstrated that older adults improved dual-task performance to the same level as younger adults at the end of training under very specific conditions. PMID:22408613

  9. Advanced instrumentation concepts for environmental control subsystems

    NASA Technical Reports Server (NTRS)

    Yang, P. Y.; Schubert, F. H.; Gyorki, J. R.; Wynveen, R. A.

    1978-01-01

    Design, evaluation and demonstration of advanced instrumentation concepts for improving performance of manned spacecraft environmental control and life support systems were successfully completed. Concepts to aid maintenance following fault detection and isolation were defined. A computer-guided fault correction instruction program was developed and demonstrated in a packaged unit which also contains the operator/system interface.

  10. Delayed benefit of naps on motor learning in preschool children.

    PubMed

    Desrochers, Phillip C; Kurdziel, Laura B F; Spencer, Rebecca M C

    2016-03-01

    Sleep benefits memory consolidation across a variety of domains in young adults. However, while declarative memories benefit from sleep in young children, such improvements are not consistently seen for procedural skill learning. Here we examined whether performance improvements on a procedural task, although not immediately observed, are evident after a longer delay when augmented by overnight sleep (24 h after learning). We trained 47 children, aged 33-71 months, on a serial reaction time task and, using a within-subject design, evaluated performance at three time points: immediately after learning, after a daytime nap (nap condition) or equivalent wake opportunity (wake condition), and 24 h after learning. Consistent with previous studies, performance improvements following the nap did not differ from performance improvements following an equivalent interval spent awake. However, significant benefits of the nap were found when performance was assessed 24 h after learning. This research demonstrates that motor skill learning is benefited by sleep, but that this benefit is only evident after an extended period of time.

  11. Filling the glass: Effects of a positive psychology intervention on executive task performance in chronic pain patients.

    PubMed

    Boselie, J J L M; Vancleef, L M G; Peters, M L

    2018-03-24

    Chronic pain is associated with emotional problems as well as difficulties in cognitive functioning. Prior experimental studies have shown that optimism, the tendency to expect that good things happen in the future, and positive emotions can counteract pain-induced task performance deficits in healthy participants. More specifically, induced optimism was found to buffer against the negative effects of experimental pain on executive functioning. This clinical experiment examined whether this beneficial effect can be extended to a chronic pain population. Patients (N = 122) were randomized to a positive psychology Internet-based intervention (PPI; n = 74) or a waiting list control condition (WLC; n = 48). The PPI consisted of positive psychology exercises that particularly target optimism, positive emotions and self-compassion. Results demonstrated that patients in the PPI condition scored higher on happiness, optimism, positive future expectancies, positive affect, self-compassion and ability to live a desired life despite pain, and scored lower on pain catastrophizing, depression and anxiety compared to patients in the WLC condition. However, executive task performance did not improve following completion of the PPI, compared to the WLC condition. Despite the lack of evidence that positive emotions and optimism can improve executive task performance in chronic pain patients, this study did convincingly demonstrate that it is possible to increase positive emotions and optimism in chronic pain patients with an online positive psychology intervention. It is imperative to further explore amendable psychological factors that may reduce the negative impact of pain on executive functioning. We demonstrated that an Internet-based positive psychology intervention strengthens optimism and positive emotions in chronic pain patients. These emotional improvements are not associated with improved executive task performance. As pain itself often cannot be relieved, it is imperative to have techniques to reduce the burden of living with chronic pain. © 2018 The Authors. European Journal of Pain published by John Wiley & Sons Ltd on behalf of European Pain Federation -EFIC®.

  12. Interacting multiple model forward filtering and backward smoothing for maneuvering target tracking

    NASA Astrophysics Data System (ADS)

    Nandakumaran, N.; Sutharsan, S.; Tharmarasa, R.; Lang, Tom; McDonald, Mike; Kirubarajan, T.

    2009-08-01

    The Interacting Multiple Model (IMM) estimator has been proven to be effective in tracking agile targets. Smoothing or retrodiction, which uses measurements beyond the current estimation time, provides better estimates of target states. Various methods have been proposed for multiple model smoothing in the literature. In this paper, a new smoothing method, which involves forward filtering followed by backward smoothing while maintaining the fundamental spirit of the IMM, is proposed. The forward filtering is performed using the standard IMM recursion, while the backward smoothing is performed using a novel interacting smoothing recursion. This backward recursion mimics the IMM estimator in the backward direction, where each mode conditioned smoother uses standard Kalman smoothing recursion. Resulting algorithm provides improved but delayed estimates of target states. Simulation studies are performed to demonstrate the improved performance with a maneuvering target scenario. The comparison with existing methods confirms the improved smoothing accuracy. This improvement results from avoiding the augmented state vector used by other algorithms. In addition, the new technique to account for model switching in smoothing is a key in improving the performance.

  13. Reverse alignment "mirror image" visualization as a laparoscopic training tool improves task performance.

    PubMed

    Dunnican, Ward J; Singh, T Paul; Ata, Ashar; Bendana, Emma E; Conlee, Thomas D; Dolce, Charles J; Ramakrishnan, Rakesh

    2010-06-01

    Reverse alignment (mirror image) visualization is a disconcerting situation occasionally faced during laparoscopic operations. This occurs when the camera faces back at the surgeon in the opposite direction from which the surgeon's body and instruments are facing. Most surgeons will attempt to optimize trocar and camera placement to avoid this situation. The authors' objective was to determine whether the intentional use of reverse alignment visualization during laparoscopic training would improve performance. A standard box trainer was configured for reverse alignment, and 34 medical students and junior surgical residents were randomized to train with either forward alignment (DIRECT) or reverse alignment (MIRROR) visualization. Enrollees were tested on both modalities before and after a 4-week structured training program specific to their modality. Student's t test was used to determine differences in task performance between the 2 groups. Twenty-one participants completed the study (10 DIRECT, 11 MIRROR). There were no significant differences in performance time between DIRECT or MIRROR participants during forward or reverse alignment initial testing. At final testing, DIRECT participants had improved times only in forward alignment performance; they demonstrated no significant improvement in reverse alignment performance. MIRROR participants had significant time improvement in both forward and reverse alignment performance at final testing. Reverse alignment imaging for laparoscopic training improves task performance for both reverse alignment and forward alignment tasks. This may be translated into improved performance in the operating room when faced with reverse alignment situations. Minimal lab training can account for drastic adaptation to this environment.

  14. Respiratory muscle endurance after training in athletes and non-athletes: A systematic review and meta-analysis.

    PubMed

    Sales, Ana Tereza do N; Fregonezi, Guilherme A de F; Ramsook, Andrew H; Guenette, Jordan A; Lima, Illia Nadinne D F; Reid, W Darlene

    2016-01-01

    The objectives of this systematic review was to evaluate the effects of respiratory muscle training (RMT) on respiratory muscle endurance (RME) and to determine the RME test that demonstrates the most consistent changes after RMT. Electronic searches were conducted in EMBASE, MEDLINE, COCHRANE CENTRAL, CINHAL and SPORTDiscus. The PEDro scale was used for quality assessment and meta-analysis were performed to compare effect sizes of different RME tests. Twenty studies met the inclusion criteria. Isocapnic hyperpnea training was performed in 40% of the studies. Meta-analysis showed that RMT improves RME in athletes (P = 0.0007) and non-athletes (P = 0.001). Subgroup analysis showed differences among tests; maximal sustainable ventilatory capacity (MSVC) and maximal sustainable threshold loading tests demonstrated significant improvement after RMT (P = 0.007; P = 0.003 respectively) compared to the maximal voluntary ventilation (MVV) (P = 0.11) in athletes whereas significant improvement after RMT was only shown by MSVC in non-athletes. The effect size of MSVC was greater compared to MVV in studies that performed both tests. The meta-analysis results provide evidence that RMT improves RME in athletes and non-athletes and MSVC test that examine endurance over several minutes are more sensitive to improvement after RMT. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Interfacial Surface Modification via Nanoimprinting to Increase Open-Circuit Voltage of Organic Solar Cells

    NASA Astrophysics Data System (ADS)

    Emah, Joseph B.; George, Nyakno J.; Akpan, Usenobong B.

    2017-08-01

    The low-cost patterning of poly(3,4-ethylenedioxythiophene) poly(4-styrenesulfonate) (PEDOT:PSS) interfacial layers inserted between indium tin oxide and poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61-butyric acid ester blends leads to an improvement in organic photovoltaics (OPV) device performance. Significantly, improvements in all device parameters, including the open-circuit voltage, are achieved. The nanoimprinted devices improved further as the pattern period and imprinting depth was reduced from 727 nm and 42 nm to 340 nm and 10 nm, respectively. A residue of poly(dimethylsiloxane) (PDMS) is found on the interfacial PEDOT:PSS film following patterning and can be used to explain the increase in OPV performance. Ultraviolet photoelectron spectroscopy measurements of the PEDOT:PSS interfacial layer demonstrated a reduction of the work function of 0.4 eV following nanoimprinting which may originate from chemical modification of the PDMS residue or interfacial dipole formation supported by x-ray photoelectron spectroscopy analysis. Ultimately, we have demonstrated a 39% improvement in OPV device performance via a simple low-cost modification of the anode interfacial layer. This improvement can be assigned to two effects resulting from a PDMS residue on the PEDOT:PSS surface: (1) the reduction of the anode work function which in turn decreases the hole extraction barrier, and (2) the reduction of electron transfer from the highest occupied molecular orbital of PCBM to the anode.

  16. High Thermal Conductivity Carbon Nanomaterials for Improved Thermal Management in Armament Composites

    DTIC Science & Technology

    2017-03-01

    polymer matrices. In addition to improving mechanical and electrical properties, these forms of carbon typically demonstrate high intrinsic thermal...conductivities, a property that could be useful in improving the thermal dissipation performance of polymer matrix composites. In this study, carbon...nanotubes, carbon nanofibers and graphene have been added to polymers and polymer matrix composites in order to study the effect on the thermal

  17. Interteaching: The Effects of Discussion Group Size on Undergraduate Student Performance and Preference

    ERIC Educational Resources Information Center

    Gutierrez, Michael

    2017-01-01

    Interteaching is a college teaching method grounded in the principles of applied behavior analysis. Research on interteaching demonstrates that it improves academic performance, and students report greater satisfaction with interteaching as compared to traditional teaching styles. The current study investigates whether discussion group size, a…

  18. Using ROI to Demonstrate Performance Value in the Public Sector

    ERIC Educational Resources Information Center

    Phillips, Jack J.; Phillips, Patti

    2009-01-01

    The demand for accountability through measurement continues to increase. Although much progress has been made, it remains an issue that challenges even the most sophisticated and progressive performance improvement function. This article provides an overview of best practices in the return-on-investment process and describes how applying these…

  19. Adaptive proximate time-optimal servomechanisms - Continuous time case

    NASA Technical Reports Server (NTRS)

    Workman, M. L.; Kosut, R. L.; Franklin, G. F.

    1987-01-01

    A Proximate Time-Optimal Servo (PTOS) is developed, along with conditions for its stability. An algorithm is proposed for adapting the PTOS (APTOS) to improve performance in the face of uncertain plant parameters. Under ideal conditions APTOS is shown to be uniformly asymptotically stable. Simulation results demonstrate the predicted performance.

  20. Metacognition and Transfer: Keys to Improving Marketing Education

    ERIC Educational Resources Information Center

    Ramocki, Stephen P.

    2007-01-01

    A primary purpose of marketing education is to prepare students to perform throughout their careers, and performance largely relies on transferability of knowledge. It has been demonstrated that training in metacognition, along with emphasis on transfer, does lead to increased probability that knowledge will be transferred into environments…

  1. Cognitive Strategies and Skill Acquisition in Musical Performance.

    ERIC Educational Resources Information Center

    McPherson, Gary E.

    1997-01-01

    Reports on a longitudinal study of high school instrumentalists that examined the development of four distinct types of musical performance (playing by ear, playing from memory, sight reading, and improvising) over three years. Reveals a significant improvement in these skills while also demonstrating changes in aural and creative activities. (CMK)

  2. Learning Molecular Structures in a Tangible Augmented Reality Environment

    ERIC Educational Resources Information Center

    Asai, Kikuo; Takase, Norio

    2011-01-01

    This article presents the characteristics of using a tangible table top environment produced by augmented reality (AR), aimed at improving the environment in which learners observe three-dimensional molecular structures. The authors perform two evaluation experiments. A performance test for a user interface demonstrates that learners with a…

  3. Design options for improved performance with high-density carbon ablators and low-gas fill hohlraum targets

    NASA Astrophysics Data System (ADS)

    Berzak Hopkins, L.; Divol, L.; Lepape, S.; Meezan, N. B.; Dewald, E.; Ho, D.; Khan, S.; Pak, A.; Ralph, J.; Ross, J. S.

    2016-10-01

    Recent simulation-based and experimental work using high-density carbon ablators in unlined uranium hohlraums with 0.3 mg/cc helium fill have demonstrated round implosions with minimal evolution of Legendre moment P2 during burn. To extend this promising work, design studies have been performed to explore potential performance improvements with larger capsules, while maintaining similar case-to-capsule target ratios. We present here the results of these design studies, which will motivate a series of upcoming experiments at the National Ignition Facility. Prepared by LLNL under Contract DE-AC52-07NA27344.

  4. Adaptive Wing Camber Optimization: A Periodic Perturbation Approach

    NASA Technical Reports Server (NTRS)

    Espana, Martin; Gilyard, Glenn

    1994-01-01

    Available redundancy among aircraft control surfaces allows for effective wing camber modifications. As shown in the past, this fact can be used to improve aircraft performance. To date, however, algorithm developments for in-flight camber optimization have been limited. This paper presents a perturbational approach for cruise optimization through in-flight camber adaptation. The method uses, as a performance index, an indirect measurement of the instantaneous net thrust. As such, the actual performance improvement comes from the integrated effects of airframe and engine. The algorithm, whose design and robustness properties are discussed, is demonstrated on the NASA Dryden B-720 flight simulator.

  5. Design and Demonstration of Emergency Control Modes for Enhanced Engine Performance

    NASA Technical Reports Server (NTRS)

    Liu, Yuan; Litt, Jonathan S.; Guo, Ten-Huei

    2013-01-01

    A design concept is presented for developing control modes that enhance aircraft engine performance during emergency flight scenarios. The benefits of increased engine performance to overall vehicle survivability during these situations may outweigh the accompanied elevated risk of engine failure. The objective involves building control logic that can consistently increase engine performance beyond designed maximum levels based on an allowable heightened probability of failure. This concept is applied to two previously developed control modes: an overthrust mode that increases maximum engine thrust output and a faster response mode that improves thrust response to dynamic throttle commands. This paper describes the redesign of these control modes and presents simulation results demonstrating both enhanced engine performance and robust maintenance of the desired elevated risk level.

  6. Roll-to-roll fabrication of large scale and regular arrays of three-dimensional nanospikes for high efficiency and flexible photovoltaics

    PubMed Central

    Leung, Siu-Fung; Gu, Leilei; Zhang, Qianpeng; Tsui, Kwong-Hoi; Shieh, Jia-Min; Shen, Chang-Hong; Hsiao, Tzu-Hsuan; Hsu, Chin-Hung; Lu, Linfeng; Li, Dongdong; Lin, Qingfeng; Fan, Zhiyong

    2014-01-01

    Three-dimensional (3-D) nanostructures have demonstrated enticing potency to boost performance of photovoltaic devices primarily owning to the improved photon capturing capability. Nevertheless, cost-effective and scalable fabrication of regular 3-D nanostructures with decent robustness and flexibility still remains as a challenging task. Meanwhile, establishing rational design guidelines for 3-D nanostructured solar cells with the balanced electrical and optical performance are of paramount importance and in urgent need. Herein, regular arrays of 3-D nanospikes (NSPs) were fabricated on flexible aluminum foil with a roll-to-roll compatible process. The NSPs have precisely controlled geometry and periodicity which allow systematic investigation on geometry dependent optical and electrical performance of the devices with experiments and modeling. Intriguingly, it has been discovered that the efficiency of an amorphous-Si (a-Si) photovoltaic device fabricated on NSPs can be improved by 43%, as compared to its planar counterpart, in an optimal case. Furthermore, large scale flexible NSP solar cell devices have been fabricated and demonstrated. These results not only have shed light on the design rules of high performance nanostructured solar cells, but also demonstrated a highly practical process to fabricate efficient solar panels with 3-D nanostructures, thus may have immediate impact on thin film photovoltaic industry. PMID:24603964

  7. Roll-to-roll fabrication of large scale and regular arrays of three-dimensional nanospikes for high efficiency and flexible photovoltaics.

    PubMed

    Leung, Siu-Fung; Gu, Leilei; Zhang, Qianpeng; Tsui, Kwong-Hoi; Shieh, Jia-Min; Shen, Chang-Hong; Hsiao, Tzu-Hsuan; Hsu, Chin-Hung; Lu, Linfeng; Li, Dongdong; Lin, Qingfeng; Fan, Zhiyong

    2014-03-07

    Three-dimensional (3-D) nanostructures have demonstrated enticing potency to boost performance of photovoltaic devices primarily owning to the improved photon capturing capability. Nevertheless, cost-effective and scalable fabrication of regular 3-D nanostructures with decent robustness and flexibility still remains as a challenging task. Meanwhile, establishing rational design guidelines for 3-D nanostructured solar cells with the balanced electrical and optical performance are of paramount importance and in urgent need. Herein, regular arrays of 3-D nanospikes (NSPs) were fabricated on flexible aluminum foil with a roll-to-roll compatible process. The NSPs have precisely controlled geometry and periodicity which allow systematic investigation on geometry dependent optical and electrical performance of the devices with experiments and modeling. Intriguingly, it has been discovered that the efficiency of an amorphous-Si (a-Si) photovoltaic device fabricated on NSPs can be improved by 43%, as compared to its planar counterpart, in an optimal case. Furthermore, large scale flexible NSP solar cell devices have been fabricated and demonstrated. These results not only have shed light on the design rules of high performance nanostructured solar cells, but also demonstrated a highly practical process to fabricate efficient solar panels with 3-D nanostructures, thus may have immediate impact on thin film photovoltaic industry.

  8. Quality improvement in childhood obesity management through the maintenance of certification process.

    PubMed

    Huang, Jeannie S; Chun, Stanford; Sandhu, Amanpreet; Terrones, Laura

    2013-11-01

    To assess the Health and Obesity: Prevention and Education (HOPE) Curriculum Project, a web-based clinician education program that promotes appropriate screening, prevention, and management of weight among youth by pediatric practitioners, based on the 2007 Expert Committee recommendations. The project currently provides Maintenance of Certification (MOC) Part 4 credit through the American Board of Pediatrics. Participants identified themselves to the HOPE MOC Part 4 program. Enrollees were required to complete all continuing medical education modules (10.5 hours). Knowledge acquisition and self-reported confidence levels related to screening, prevention, and management practices of pediatric obesity were measured using preknowledge and postknowledge questionnaires. Participants were also required to perform a quality improvement project and submit practice performance data from repeated medical chart reviews over time. Knowledge acquisition, self-efficacy, and practice performance data were analyzed using repeated-measures analyses. The 51 participants demonstrated significant improvements in knowledge acquisition and self-efficacy scores after viewing individual modules. In addition, participants demonstrated significant improvements in measured clinical compliance with recommended practices over time. Participation in the HOPE MOC Part 4 program appeared to improve knowledge acquisition, self-efficacy, and physician compliance with recommended practice recommendations for the screening, prevention, and management of pediatric obesity. Further data are required to determine whether such practice-based improvements translate into actual reduction in patient weight and/or reduction in health-related costs related to overweight and obesity in youth. Copyright © 2013 Mosby, Inc. All rights reserved.

  9. Fluid infusion system

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Performance testing carried out in the development of the prototype zero-g fluid infusion system is described and summarized. Engineering tests were performed in the course of development, both on the original breadboard device and on the prototype system. This testing was aimed at establishing baseline system performance parameters and facilitating improvements. Acceptance testing was then performed on the prototype system to verify functional performance. Acceptance testing included a demonstration of the fluid infusion system on a laboratory animal.

  10. Propeller flow visualization techniques

    NASA Technical Reports Server (NTRS)

    Stefko, G. L.; Paulovich, F. J.; Greissing, J. P.; Walker, E. D.

    1982-01-01

    Propeller flow visualization techniques were tested. The actual operating blade shape as it determines the actual propeller performance and noise was established. The ability to photographically determine the advanced propeller blade tip deflections, local flow field conditions, and gain insight into aeroelastic instability is demonstrated. The analytical prediction methods which are being developed can be compared with experimental data. These comparisons contribute to the verification of these improved methods and give improved capability for designing future advanced propellers with enhanced performance and noise characteristics.

  11. Performance Improvement of Raman Distributed Temperature System by Using Noise Suppression

    NASA Astrophysics Data System (ADS)

    Li, Jian; Li, Yunting; Zhang, Mingjiang; Liu, Yi; Zhang, Jianzhong; Yan, Baoqiang; Wang, Dong; Jin, Baoquan

    2018-06-01

    In Raman distributed temperature system, the key factor for performance improvement is noise suppression, which seriously affects the sensing distance and temperature accuracy. Therefore, we propose and experimentally demonstrate dynamic noise difference algorithm and wavelet transform modulus maximum (WTMM) to de-noising Raman anti-Stokes signal. Experimental results show that the sensing distance can increase from 3 km to 11.5 km and the temperature accuracy increases to 1.58 °C at the sensing distance of 10.4 km.

  12. Development of an EMG-ACC-Based Upper Limb Rehabilitation Training System.

    PubMed

    Ling Liu; Xiang Chen; Zhiyuan Lu; Shuai Cao; De Wu; Xu Zhang

    2017-03-01

    This paper focuses on the development of an upper limb rehabilitation training system designed for use by children with cerebral palsy (CP). It attempts to meet the requirements of in-home training by taking advantage of the combination of portable accelerometers (ACC) and surface electromyography (SEMG) sensors worn on the upper limb to capture functional movements. In the proposed system, the EMG-ACC acquisition device works essentially as wireless game controller, and three rehabilitation games were designed for improving upper limb motor function under a clinician's guidance. The games were developed on the Android platform based on a physical engine called Box2D. The results of a system performance test demonstrated that the developed games can respond to the upper limb actions within 210 ms. Positive questionnaire feedbacks from twenty CP subjects who participated in the game test verified both the feasibility and usability of the system. Results of a long-term game training conducted with three CP subjects demonstrated that CP patients could improve in their game performance through repetitive training, and persistent training was needed to improve and enhance the rehabilitation effect. According to our experimental results, the novel multi-feedback SEMG-ACC-based user interface improved the users' initiative and performance in rehabilitation training.

  13. Performance Optimization of Marine Science and Numerical Modeling on HPC Cluster

    PubMed Central

    Yang, Dongdong; Yang, Hailong; Wang, Luming; Zhou, Yucong; Zhang, Zhiyuan; Wang, Rui; Liu, Yi

    2017-01-01

    Marine science and numerical modeling (MASNUM) is widely used in forecasting ocean wave movement, through simulating the variation tendency of the ocean wave. Although efforts have been devoted to improve the performance of MASNUM from various aspects by existing work, there is still large space unexplored for further performance improvement. In this paper, we aim at improving the performance of propagation solver and data access during the simulation, in addition to the efficiency of output I/O and load balance. Our optimizations include several effective techniques such as the algorithm redesign, load distribution optimization, parallel I/O and data access optimization. The experimental results demonstrate that our approach achieves higher performance compared to the state-of-the-art work, about 3.5x speedup without degrading the prediction accuracy. In addition, the parameter sensitivity analysis shows our optimizations are effective under various topography resolutions and output frequencies. PMID:28045972

  14. Real-time cartesian force feedback control of a teleoperated robot

    NASA Technical Reports Server (NTRS)

    Campbell, Perry

    1989-01-01

    Active cartesian force control of a teleoperated robot is investigated. An economical microcomputer based control method was tested. Limitations are discussed and methods of performance improvement suggested. To demonstrate the performance of this technique, a preliminary test was performed with success. A general purpose bilateral force reflecting hand controller is currently being constructed based on this control method.

  15. Paying It Forward: A Technical Assistance Guide for Developing and Implementing Performance-Based Scholarships. The Performance-Based Scholarship Demonstration

    ERIC Educational Resources Information Center

    Welbeck, Rashida; Ware, Michelle; Cerna, Oscar; Valenzuela, Ireri

    2014-01-01

    Difficulties in paying for college and in maintaining good academic performance are two major hurdles to college graduation for low-income students. In recent years, state and federal budgets for postsecondary education have been cut significantly, limiting the options policymakers, education leaders, and communities have to improve rates of…

  16. A seismic optimization procedure for reinforced concrete framed buildings based on eigenfrequency optimization

    NASA Astrophysics Data System (ADS)

    Arroyo, Orlando; Gutiérrez, Sergio

    2017-07-01

    Several seismic optimization methods have been proposed to improve the performance of reinforced concrete framed (RCF) buildings; however, they have not been widely adopted among practising engineers because they require complex nonlinear models and are computationally expensive. This article presents a procedure to improve the seismic performance of RCF buildings based on eigenfrequency optimization, which is effective, simple to implement and efficient. The method is used to optimize a 10-storey regular building, and its effectiveness is demonstrated by nonlinear time history analyses, which show important reductions in storey drifts and lateral displacements compared to a non-optimized building. A second example for an irregular six-storey building demonstrates that the method provides benefits to a wide range of RCF structures and supports the applicability of the proposed method.

  17. Experimental demonstration of the transmission performance for LDPC-coded multiband OFDM ultra-wideband over fiber system

    NASA Astrophysics Data System (ADS)

    He, Jing; Wen, Xuejie; Chen, Ming; Chen, Lin; Su, Jinshu

    2015-01-01

    To improve the transmission performance of multiband orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband (UWB) over optical fiber, a pre-coding scheme based on low-density parity-check (LDPC) is adopted and experimentally demonstrated in the intensity-modulation and direct-detection MB-OFDM UWB over fiber system. Meanwhile, a symbol synchronization and pilot-aided channel estimation scheme is implemented on the receiver of the MB-OFDM UWB over fiber system. The experimental results show that the LDPC pre-coding scheme can work effectively in the MB-OFDM UWB over fiber system. After 70 km standard single-mode fiber (SSMF) transmission, at the bit error rate of 1 × 10-3, the receiver sensitivities are improved about 4 dB when the LDPC code rate is 75%.

  18. Controlled Speed Accessory Drive demonstration program

    NASA Technical Reports Server (NTRS)

    Hoehn, F. W.

    1981-01-01

    A Controlled Speed Accessory Drive System was examined in an effort to improve the fuel economy of passenger cars. Concept feasibility and the performance of a typical system during actual road driving conditions were demonstrated. The CSAD system is described as a mechanical device which limits engine accessory speeds, thereby reducing parasitic horsepower losses and improving overall vehicle fuel economy. Fuel consumption data were compiled for fleets of GSA vehicles. Various motor pool locations were selected, each representing different climatic conditions. On the basis of a total accumulated fleet usage of nearly three million miles, an overall fuel economy improvement of 6 percent to 7 percent was demonstrated. Coincident chassis dynamometer tests were accomplished on selected vehicles to establish the effect of different accessory drive systems on exhaust emissions, and to evaluate the magnitude of the mileage benefits which could be derived.

  19. Berkeley Lab - Materials Sciences Division

    Science.gov Websites

    demonstrated a way to make it work. New Discovery Could Improve Organic Solar Cell Performance MSD's Center for lead to gains in efficiency for organic solar cells Rob Ritchie featured in Nature Communications Discover Material Ideal for Smart Photovoltaic Windows ▲ New Discovery Could Improve Organic Solar Cell

  20. Improving resident performance on standardized assessments of medical knowledge: a retrospective analysis of interventions correlated to American Board of Surgery In-Service Training Examination performance.

    PubMed

    Buckley, Elaine Jayne; Markwell, Stephen; Farr, Debb; Sanfey, Hilary; Mellinger, John

    2015-10-01

    American Board of Surgery In-Service Training Examination (ABSITE) scores are used to assess individual progress and predict board pass rates. We reviewed strategies to enhance ABSITE performance and their impact within a surgery residency. Several interventions were introduced from 2010 to 2014. A retrospective review was undertaken evaluating these and correlating them to ABSITE performance. Analyses of variance and linear trends were performed for ABSITE, United States Medical Licensing Examination (USMLEs), mock oral, and mock ABSITE scores followed by post hoc analyses if significant. Results were correlated with core curricular changes. ABSITE mean percentile increased 34% in 4 years with significant performance improvement and increasing linear trends in postgraduate year (PGY)1 and PGY4 ABSITE scores. Mock ABSITE introduction correlated to significant improvement in ABSITE scores for PGY4 and PGY5. Mock oral introduction correlated with significant improvement in PGY1 and PGY3. Our study demonstrates an improvement in mean program ABSITE percentiles correlating with multiple interventions. Similar strategies may be useful for other programs. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Arcjet thruster research and technology

    NASA Technical Reports Server (NTRS)

    Makel, Darby B.; Cann, Gordon L.

    1988-01-01

    The design, analysis, and performance testing of an advanced lower power arcjet is described. A high impedance, vortex stabilized 1-kw class arcjet has been studied. A baseline research thruster has been built and endurance and performance tested. This advanced arcjet has demonstrated long lifetime characteristics, but lower than expected performance. Analysis of the specific design has identified modifications which should improve performance and maintain the long life time shown by the arcjet.

  2. Ready to rumble: how team personality composition and task conflict interact to improve performance.

    PubMed

    Bradley, Bret H; Klotz, Anthony C; Postlethwaite, Bennett E; Brown, Kenneth G

    2013-03-01

    Although prior work has proposed a number of conditions under which task conflict in teams may improve performance, composition variables have been left unexplored. Given the effects of personality traits on team processes and outcomes demonstrated in prior work, investigating whether specific personality compositions influence the effect of task conflict on team performance is critical to researchers' understanding of conflict in teams. Our results indicate that team-level averages of both openness to experience and emotional stability function as moderators of the relationship between task conflict and team performance. Specifically, task conflict had a positive impact on performance in teams with high levels of openness or emotional stability; in contrast, task conflict had a negative impact on performance in teams with low levels of openness or emotional stability. Thus, when task conflict emerges, teams composed of members who are open minded or emotionally stable are best able to leverage conflict to improve performance. Implications for theory and practice are discussed.

  3. Can a virtual reality surgical simulation training provide a self-driven and mentor-free skills learning? Investigation of the practical influence of the performance metrics from the virtual reality robotic surgery simulator on the skill learning and associated cognitive workloads.

    PubMed

    Lee, Gyusung I; Lee, Mija R

    2018-01-01

    While it is often claimed that virtual reality (VR) training system can offer self-directed and mentor-free skill learning using the system's performance metrics (PM), no studies have yet provided evidence-based confirmation. This experimental study investigated what extent to which trainees achieved their self-learning with a current VR simulator and whether additional mentoring improved skill learning, skill transfer and cognitive workloads in robotic surgery simulation training. Thirty-two surgical trainees were randomly assigned to either the Control-Group (CG) or Experiment-Group (EG). While the CG participants reviewed the PM at their discretion, the EG participants had explanations about PM and instructions on how to improve scores. Each subject completed a 5-week training using four simulation tasks. Pre- and post-training data were collected using both a simulator and robot. Peri-training data were collected after each session. Skill learning, time spent on PM (TPM), and cognitive workloads were compared between groups. After the simulation training, CG showed substantially lower simulation task scores (82.9 ± 6.0) compared with EG (93.2 ± 4.8). Both groups demonstrated improved physical model tasks performance with the actual robot, but the EG had a greater improvement in two tasks. The EG exhibited lower global mental workload/distress, higher engagement, and a better understanding regarding using PM to improve performance. The EG's TPM was initially long but substantially shortened as the group became familiar with PM. Our study demonstrated that the current VR simulator offered limited self-skill learning and additional mentoring still played an important role in improving the robotic surgery simulation training.

  4. The effects of high resistance-few repetitions and low resistance-high repetitions resistance training on climbing performance.

    PubMed

    Hermans, Espen; Andersen, Vidar; Saeterbakken, Atle Hole

    2017-05-01

    The aim of the study was to compare the effects of different strength training intensities on climbing performance, climbing-specific tests and a general strength test. Thirty lower grade and intermediate-level climbers participated in a 10-week training programme. The participants were randomized into three groups: high resistance-few repetitions training groups (HR-FR), low resistance-high repetitions training groups (LR-HR) and a control group (CON) which continued climbing/training as usual. Post-testing results demonstrated statistical tendencies for climbing performance improvements in the HR-FR and LR-HR (p = 0.088-0.090, effect size = 0.55-0.73), but no differences were observed between the groups (p = 0.950). For the climbing-specific tests, no differences were observed between the groups (p = 0.507-1.000), but the HR-FR and LR-HR improved their time in both Dead-hang (p = 0.004-0.026) and Bent-arm hang (p < 0.001-0.002). The HR-FR and LR-HR improved their 12RM strength in pull-down (p ≤ 0.001), but not the CON group (p = 0.250). No differences were observed in the CON group in any of the tests (p = 0.190-0.596) with the exception of improvement in Bent-arm Hang (p = 0.018). The training groups reduced their climbing sessions during the intervention compared to the CON group (p = 0.057-0.074). In conclusion, HR-FR and LR-HR training programmes demonstrated an 11% and 12% non-significant improvement in climbing performance despite a 50% reduction in climbing sessions, but improved the results in strength and climbing-specific tests. None of the training intensities was superior compared to the others.

  5. Impact of Performance Improvement Continuing Medical Education on Cardiometabolic Risk Factor Control: The COSEHC Initiative

    PubMed Central

    Joyner, JaNae; Moore, Michael A.; Simmons, Debra R.; Forrest, Brian; Yu-Isenberg, Kristina; Piccione, Ron; Caton, Kirt; Lackland, Daniel T.; Ferrario, Carlos M.

    2016-01-01

    Introduction The Consortium for Southeastern Hypertension Control (COSEHC) implemented a study to assess benefits of a performance improvement continuing medical education (PI CME) activity focused on cardiometabolic risk factor management in primary care patients. Methods Using the plan-do-study-act (PDSA) model as the foundation, this PI CME activity aimed at improving practice gaps by integrating evidence-based clinical interventions, physician-patient education, processes of care, performance metrics, and patient outcomes. The PI CME intervention was implemented in a group of South Carolina physician practices, while a comparable physician practice group served as a control. Performance outcomes at 6 months included changes in patients’ cardiometabolic risk factor values and control rates from baseline. We also compared changes in diabetic, African American, the elderly (> 65 years), and female patient subpopulations and in patients with uncontrolled risk factors at baseline. Results Only women receiving health care by intervention physicians showed a statistical improvement in their cardiometabolic risk factors as evidenced by a −3.0 mg/dL and a −3.5 mg/dL decrease in mean LDL cholesterol and non-HDL cholesterol, respectively, and a −7.0 mg/dL decrease in LDL cholesterol among females with uncontrolled baseline LDL cholesterol values. No other statistical differences were found. Discussion These data demonstrate that our PI CME activity is a useful strategy in assisting physicians to improve their management of cardiometabolic control rates in female patients with abnormal cholesterol control. Other studies that extend across longer PI CME PDSA periods may be needed to demonstrate statistical improvements in overall cardiometabolic treatment goals in men, women, and various subpopulations. PMID:24648361

  6. Improved Speech Coding Based on Open-Loop Parameter Estimation

    NASA Technical Reports Server (NTRS)

    Juang, Jer-Nan; Chen, Ya-Chin; Longman, Richard W.

    2000-01-01

    A nonlinear optimization algorithm for linear predictive speech coding was developed early that not only optimizes the linear model coefficients for the open loop predictor, but does the optimization including the effects of quantization of the transmitted residual. It also simultaneously optimizes the quantization levels used for each speech segment. In this paper, we present an improved method for initialization of this nonlinear algorithm, and demonstrate substantial improvements in performance. In addition, the new procedure produces monotonically improving speech quality with increasing numbers of bits used in the transmitted error residual. Examples of speech encoding and decoding are given for 8 speech segments and signal to noise levels as high as 47 dB are produced. As in typical linear predictive coding, the optimization is done on the open loop speech analysis model. Here we demonstrate that minimizing the error of the closed loop speech reconstruction, instead of the simpler open loop optimization, is likely to produce negligible improvement in speech quality. The examples suggest that the algorithm here is close to giving the best performance obtainable from a linear model, for the chosen order with the chosen number of bits for the codebook.

  7. Two-well terahertz quantum cascade lasers with suppressed carrier leakage

    DOE PAGES

    Albo, Asaf; Flores, Yuri V.; Hu, Qing; ...

    2017-09-11

    The mechanisms that limit the temperature performance of diagonal GaAs/Al 0.15GaAs 0.85-based terahertz quantum cascade lasers (THz-QCLs) have been identified as thermally activated leakage of charge carriers through excited states into the continuum. THz-QCLs with energetically higher-laying excited states supported by sufficiently high barriers aim to eliminate these leakage mechanisms and lead to improved temperature performance. Although suppression of thermally activated carrier leakage was realized in a three-well THz-QCL based on a resonant-phonon scheme, no improvement in the temperature performance was reported thus far. Here, we report a major improvement in the temperature performance of a two-quantum-well direct-phonon THz-QCL structure.more » We show that the improved laser performance is due to the suppression of the thermally activated carrier leakage into the continuum with the increase in the injection barrier height. Furthermore, we demonstrate that high-barrier two-well structures can support a clean three-level laser system at elevated temperatures, which opens the opportunity to achieve temperature performance beyond the state-of-the-art.« less

  8. Two-well terahertz quantum cascade lasers with suppressed carrier leakage

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

    Albo, Asaf; Flores, Yuri V.; Hu, Qing

    The mechanisms that limit the temperature performance of diagonal GaAs/Al 0.15GaAs 0.85-based terahertz quantum cascade lasers (THz-QCLs) have been identified as thermally activated leakage of charge carriers through excited states into the continuum. THz-QCLs with energetically higher-laying excited states supported by sufficiently high barriers aim to eliminate these leakage mechanisms and lead to improved temperature performance. Although suppression of thermally activated carrier leakage was realized in a three-well THz-QCL based on a resonant-phonon scheme, no improvement in the temperature performance was reported thus far. Here, we report a major improvement in the temperature performance of a two-quantum-well direct-phonon THz-QCL structure.more » We show that the improved laser performance is due to the suppression of the thermally activated carrier leakage into the continuum with the increase in the injection barrier height. Furthermore, we demonstrate that high-barrier two-well structures can support a clean three-level laser system at elevated temperatures, which opens the opportunity to achieve temperature performance beyond the state-of-the-art.« less

  9. Two-well terahertz quantum cascade lasers with suppressed carrier leakage

    NASA Astrophysics Data System (ADS)

    Albo, Asaf; Flores, Yuri V.; Hu, Qing; Reno, John L.

    2017-09-01

    The mechanisms that limit the temperature performance of diagonal GaAs/Al0.15GaAs0.85-based terahertz quantum cascade lasers (THz-QCLs) have been identified as thermally activated leakage of charge carriers through excited states into the continuum. THz-QCLs with energetically higher-laying excited states supported by sufficiently high barriers aim to eliminate these leakage mechanisms and lead to improved temperature performance. Although suppression of thermally activated carrier leakage was realized in a three-well THz-QCL based on a resonant-phonon scheme, no improvement in the temperature performance was reported thus far. Here, we report a major improvement in the temperature performance of a two-quantum-well direct-phonon THz-QCL structure. We show that the improved laser performance is due to the suppression of the thermally activated carrier leakage into the continuum with the increase in the injection barrier height. Moreover, we demonstrate that high-barrier two-well structures can support a clean three-level laser system at elevated temperatures, which opens the opportunity to achieve temperature performance beyond the state-of-the-art.

  10. Joint Optics Structures Experiment (JOSE)

    NASA Technical Reports Server (NTRS)

    Founds, David

    1987-01-01

    The objectives of the JOSE program is to develop, demonstrate, and evaluate active vibration suppression techniques for Directed Energy Weapons (DEW). DEW system performance is highly influenced by the line-of-sight (LOS) stability and in some cases by the wave front quality. The missions envisioned for DEW systems by the Strategic Defense Initiative require LOS stability and wave front quality to be significantly improved over any current demonstrated capability. The Active Control of Space Structures (ACOSS) program led to the development of a number of promising structural control techniques. DEW structures are vastly more complex than any structures controlled to date. They will be subject to disturbances with significantly higher magnitudes and wider bandwidths, while holding higher tolerances on allowable motions and deformations. Meeting the performance requirements of the JOSE program requires upgrading the ACOSS techniques to meet new more stringent requirements, the development of requisite sensors and acturators, improved control processors, highly accurate system identification methods, and the integration of hardware and methodologies into a successful demonstration.

  11. Longitudinal effects of a collegiate strength and conditioning program in American football.

    PubMed

    Stodden, David F; Galitski, Hayes M

    2010-09-01

    The purpose of this study was to examine the longitudinal effects of a strength and conditioning program on selected body composition and performance data over 4 consecutive years of training. Body mass, percent body fat, lean body mass, proagility (18.3 m shuttle), 36.6-m (40-yd) sprint, bench press, chin-ups, vertical jump, and power index data for 84 National Collegiate Athletic Association division IA collegiate football players were examined. In addition to examining data on all athletes, data were analyzed on specific groups categorized by position. Groups were categorized as (a) skill (wide receivers, defensive backs, and running backs), (b) big skill (linebackers, kickers, tight ends, quarterbacks, and specialists), and (c) line (offensive and defensive linemen). Data on each individual performance criteria were analyzed using pairwise t-tests to indicate changes from year to year. Results for all participants showed that the greatest number of significant improvements among test parameters occurred during the first year of training. Years 2-4 of training demonstrated inconsistent improvement among the test parameters. Bench press performance significantly improved throughout 4 years of training among all participants. Data analysis from specific position groups also revealed the greatest number of significant improvements occurred during the first year of training. Overall, the results of this study clearly demonstrate that the greatest rate of improvement in the selected performance parameters occurred during the initial year of the strength and conditioning program. This study provides valuable information for coaches to establish appropriate progression and program variation guidelines for athletes over consecutive years of training.

  12. Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer

    PubMed Central

    Rafique, Saqib; Abdullah, Shahino Mah; Shahid, Muhammad Mehmood; Ansari, Mohammad Omaish; Sulaiman, Khaulah

    2017-01-01

    This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC71BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability. PMID:28084304

  13. Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer.

    PubMed

    Rafique, Saqib; Abdullah, Shahino Mah; Shahid, Muhammad Mehmood; Ansari, Mohammad Omaish; Sulaiman, Khaulah

    2017-01-13

    This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC 71 BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability.

  14. Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer

    NASA Astrophysics Data System (ADS)

    Rafique, Saqib; Abdullah, Shahino Mah; Shahid, Muhammad Mehmood; Ansari, Mohammad Omaish; Sulaiman, Khaulah

    2017-01-01

    This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC71BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability.

  15. NASA HPCC Technology for Aerospace Analysis and Design

    NASA Technical Reports Server (NTRS)

    Schulbach, Catherine H.

    1999-01-01

    The Computational Aerosciences (CAS) Project is part of NASA's High Performance Computing and Communications Program. Its primary goal is to accelerate the availability of high-performance computing technology to the US aerospace community-thus providing the US aerospace community with key tools necessary to reduce design cycle times and increase fidelity in order to improve safety, efficiency and capability of future aerospace vehicles. A complementary goal is to hasten the emergence of a viable commercial market within the aerospace community for the advantage of the domestic computer hardware and software industry. The CAS Project selects representative aerospace problems (especially design) and uses them to focus efforts on advancing aerospace algorithms and applications, systems software, and computing machinery to demonstrate vast improvements in system performance and capability over the life of the program. Recent demonstrations have served to assess the benefits of possible performance improvements while reducing the risk of adopting high-performance computing technology. This talk will discuss past accomplishments in providing technology to the aerospace community, present efforts, and future goals. For example, the times to do full combustor and compressor simulations (of aircraft engines) have been reduced by factors of 320:1 and 400:1 respectively. While this has enabled new capabilities in engine simulation, the goal of an overnight, dynamic, multi-disciplinary, 3-dimensional simulation of an aircraft engine is still years away and will require new generations of high-end technology.

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

    PubMed

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

    2015-11-25

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

  17. Laser-only Adaptive Optics Achieves Significant Image Quality Gains Compared to Seeing-limited Observations over the Entire Sky

    NASA Astrophysics Data System (ADS)

    Howard, Ward S.; Law, Nicholas M.; Ziegler, Carl A.; Baranec, Christoph; Riddle, Reed

    2018-02-01

    Adaptive optics laser guide-star systems perform atmospheric correction of stellar wavefronts in two parts: stellar tip-tilt and high-spatial-order laser correction. The requirement of a sufficiently bright guide star in the field-of-view to correct tip-tilt limits sky coverage. In this paper, we show an improvement to effective seeing without the need for nearby bright stars, enabling full sky coverage by performing only laser-assisted wavefront correction. We used Robo-AO, the first robotic AO system, to comprehensively demonstrate this laser-only correction. We analyze observations from four years of efficient robotic operation covering 15000 targets and 42000 observations, each realizing different seeing conditions. Using an autoguider (or a post-processing software equivalent) and the laser to improve effective seeing independent of the brightness of a target, Robo-AO observations show a 39% ± 19% improvement to effective FWHM, without any tip-tilt correction. We also demonstrate that 50% encircled energy performance without tip-tilt correction remains comparable to diffraction-limited, standard Robo-AO performance. Faint-target science programs primarily limited by 50% encircled energy (e.g., those employing integral field spectrographs placed behind the AO system) may see significant benefits to sky coverage from employing laser-only AO.

  18. Relative health performance in BRICS over the past 20 years: the winners and losers.

    PubMed

    Petrie, Dennis; Tang, Kam Ki

    2014-06-01

    To determine whether the health performance of Brazil, the Russian Federation, India, China and South Africa--the countries known as BRICS--has kept in step with their economic development. Reductions in age- and sex-specific mortality seen in each BRICS country between 1990 and 2011 were measured. These results were compared with those of the best-performing countries in the world and the best-performing countries with similar income levels. We estimated each country's progress in reducing mortality and compared changes in that country's mortality rates against other countries with similar mean incomes to examine changes in avoidable mortality. The relative health performance of the five study countries differed markedly over the study period. Brazil demonstrated fairly even improvement in relative health performance across the different age and sex subgroups that we assessed. India's improvement was more modest and more varied across the subgroups. South Africa and the Russian Federation exhibited large declines in health performance as well as large sex-specific inequalities in health. Although China's levels of avoidable mortality decreased in absolute terms, the level of improvement appeared low in the context of China's economic growth. When evaluating a country's health performance in terms of avoidable mortality, it is useful to compare that performance against the performance of other countries. Such comparison allows any country-specific improvements to be distinguished from general global improvements.

  19. CF6 jet engine performance improvement: High pressure turbine roundness

    NASA Technical Reports Server (NTRS)

    Howard, W. D.; Fasching, W. A.

    1982-01-01

    An improved high pressure turbine stator reducing fuel consumption in current CF6-50 turbofan engines was developed. The feasibility of the roundness and clearance response improvements was demonstrated. Application of these improvements will result in a cruise SFC reduction of 0.22 percent for new engines. For high time engines, the improved roundness and response characteristics results in an 0.5 percent reduction in cruise SFC. A basic life capability of the improved HP turbine stator in over 800 simulated flight cycles without any sign of significant distress is shown.

  20. Large area silicon sheet by EFG. [furnace growth techniques

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The development of a technique for the production of silicon ribbon is discussed. Extensive characterization of the multiple ribbon Furnace 3A main zone temperature profile was performed and the information used to improve uniformity of heating. Irregularities in the main zone heater were associated with growth difficulties at specific cartridge locations, and growth conditions subsequently improved by profiling the main zone heater. Good growth conditions were established in all three cartridge positions. These improvements allowed multiple growth of three 10 cm wide ribbons to be demonstrated for periods of an hour on several occasions. A gas distribution system for the 10 cm cartridge was introduced and demonstrated to lead to improved ambient control during growth. Growth without and with CO2 showed that quality improvement in 10 cm ribbon grown with cold shoes results from ambient manipulation.

  1. Molecular engineering to improve carrier lifetimes for organic photovoltaic devices with thick active layers

    DOE PAGES

    Oosterhout, Stefan D.; Braunecker, Wade A.; Owczarczyk, Zbyslaw R.; ...

    2017-04-27

    The morphology of the bulk heterojunction absorber layer in an organic photovoltaic (OPV) device has a profound effect on the electrical properties and efficiency of the device. Previous work has consistently demonstrated that the solubilizing side-chains of the donor material affect these properties and device performance in a non-trivial way. Here, using Time-Resolved Microwave Conductivity (TRMC), we show by direct measurements of carrier lifetimes that the choice of side chains can also make a substantial difference in photocarrier dynamics. We have previously demonstrated a correlation between peak photoconductance measured by TRMC and device efficiencies; here, we demonstrate that TRMC photocarriermore » dynamics have an important bearing on device performance in a case study of devices made from donor materials with linear vs. branched side-chains and with variable active layer thicknesses. We use Grazing-Incidence Wide Angle X-ray Scattering to elucidate the cause of the different carrier lifetimes as a function of different aggregation behavior in the polymers. Consequently, the results help establish TRMC as a technique for screening OPV donor materials whose devices maintain performance in thick active layers (>250 nm) designed to improve light harvesting, film reproducibility, and ease of processing.« less

  2. Methodology, Methods, and Metrics for Testing and Evaluating Augmented Cognition Systems

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

    Greitzer, Frank L.

    The augmented cognition research community seeks cognitive neuroscience-based solutions to improve warfighter performance by applying and managing mitigation strategies to reduce workload and improve the throughput and quality of decisions. The focus of augmented cognition mitigation research is to define, demonstrate, and exploit neuroscience and behavioral measures that support inferences about the warfighter’s cognitive state that prescribe the nature and timing of mitigation. A research challenge is to develop valid evaluation methodologies, metrics and measures to assess the impact of augmented cognition mitigations. Two considerations are external validity, which is the extent to which the results apply to operational contexts;more » and internal validity, which reflects the reliability of performance measures and the conclusions based on analysis of results. The scientific rigor of the research methodology employed in conducting empirical investigations largely affects the validity of the findings. External validity requirements also compel us to demonstrate operational significance of mitigations. Thus it is important to demonstrate effectiveness of mitigations under specific conditions. This chapter reviews some cognitive science and methodological considerations in designing augmented cognition research studies and associated human performance metrics and analysis methods to assess the impact of augmented cognition mitigations.« less

  3. Clinically Normal Stereopsis Does Not Ensure a Performance Benefit from Stereoscopic 3D Depth Cues

    NASA Astrophysics Data System (ADS)

    McIntire, John P.; Havig, Paul R.; Harrington, Lawrence K.; Wright, Steve T.; Watamaniuk, Scott N. J.; Heft, Eric L.

    2014-09-01

    To investigate the effect of manipulating disparity on task performance and viewing comfort, twelve participants were tested on a virtual object precision placement task while viewing a stereoscopic 3D (S3D) display. All participants had normal or corrected-to-normal visual acuity, passed the Titmus stereovision clinical test, and demonstrated normal binocular function, including phorias and binocular fusion ranges. Each participant completed six experimental sessions with different maximum binocular disparity limits. The results for ten of the twelve participants were generally as expected, demonstrating a large performance advantage when S3D cues were provided. The sessions with the larger disparity limits typically resulted in the best performance, and the sessions with no S3D cues the poorest performance. However, one participant demonstrated poorer performance in sessions with smaller disparity limits but improved performance in sessions with the larger disparity limits. Another participant's performance declined whenever any S3D cues were provided. Follow-up testing suggested that the phenomenon of pseudo-stereoanomaly may account for one viewer's atypical performance, while the phenomenon of stereoanomaly might account for the other. Overall, the results demonstrate that a subset of viewers with clinically normal binocular and stereoscopic vision may have difficulty performing depth-related tasks on S3D displays. The possibility of the vergence-accommodation conflict contributing to individual performance differences is also discussed.

  4. Implementing a Parallel Image Edge Detection Algorithm Based on the Otsu-Canny Operator on the Hadoop Platform

    PubMed Central

    Wang, Min; Tian, Yun

    2018-01-01

    The Canny operator is widely used to detect edges in images. However, as the size of the image dataset increases, the edge detection performance of the Canny operator decreases and its runtime becomes excessive. To improve the runtime and edge detection performance of the Canny operator, in this paper, we propose a parallel design and implementation for an Otsu-optimized Canny operator using a MapReduce parallel programming model that runs on the Hadoop platform. The Otsu algorithm is used to optimize the Canny operator's dual threshold and improve the edge detection performance, while the MapReduce parallel programming model facilitates parallel processing for the Canny operator to solve the processing speed and communication cost problems that occur when the Canny edge detection algorithm is applied to big data. For the experiments, we constructed datasets of different scales from the Pascal VOC2012 image database. The proposed parallel Otsu-Canny edge detection algorithm performs better than other traditional edge detection algorithms. The parallel approach reduced the running time by approximately 67.2% on a Hadoop cluster architecture consisting of 5 nodes with a dataset of 60,000 images. Overall, our approach system speeds up the system by approximately 3.4 times when processing large-scale datasets, which demonstrates the obvious superiority of our method. The proposed algorithm in this study demonstrates both better edge detection performance and improved time performance. PMID:29861711

  5. Emergency in the clinic: a simulation curriculum to improve outpatient safety.

    PubMed

    Espey, Eve; Baty, Gillian; Rask, John; Chungtuyco, Michelle; Pereda, Brenda; Leeman, Lawrence

    2017-12-01

    Emergency response skills are essential when events such as seizure, anaphylaxis, or hemorrhage occur in the outpatient setting. As services and procedures increasingly move outside the hospital, training to manage complications may improve outcomes. The objective of this study was to evaluate a simulation-based curriculum in outpatient emergency management skills with the outcome measures of graded objective performance and learner self-efficacy. This pre- and postcurriculum study enrolled residents and fellows in Obstetrics and Gynecology and Family Medicine in a simulation-based, outpatient emergency management curriculum. Learners completed self-efficacy questionnaires and were videotaped managing 3 medical emergency scenarios (seizure, over-sedation/cardiopulmonary arrest, and hemorrhage) in the simulation laboratory both before and after completion of the curriculum. Evaluators who were blinded to training level scored the simulation performance videotapes using a graded rubric with critical action checklists. Scenario scores were assigned in 5 domains and globally. Paired t-tests were used to determine differences pre- and postcurriculum. Thirty residents completed the curriculum and pre- and postcurriculum testing. Subjects' objective performance scores improved in all 5 domains (P<.05) in all scenarios. When scores were stratified by level of training, all participants demonstrated global improvement. When scores were stratified by previous outpatient simulation experience, subjects with previous experience improved in all but management of excess sedation. Pre- and postcurriculum self-efficacy evaluations demonstrated improvement in all 7 measured areas: confidence, use of appropriate resources, communication skills, complex airway management, bag mask ventilation, resuscitation, and hemorrhage management. Self-efficacy assessment showed improvement in confidence managing outpatient emergencies (P=.001) and ability to communicate well in emergency situations (P<.001). A simulation-based curriculum improved both self-efficacy and objectively rated performance scores in management of outpatient medical emergencies. Simulation-based curricula should be incorporated into residency education. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Experimental analysis of robot-assisted needle insertion into porcine liver.

    PubMed

    Wang, Wendong; Shi, Yikai; Goldenberg, Andrew A; Yuan, Xiaoqing; Zhang, Peng; He, Lijing; Zou, Yingjie

    2015-01-01

    How to improve placement accuracy of needle insertion into liver tissue is of paramount interest to physicians. A robot-assisted system was developed to experimentally demonstrate its advantages in needle insertion surgeries. Experiments of needle insertion into porcine liver tissue were performed with conic tip needle (diameter 8 mm) and bevel tip needle (diameter 1.5 mm) in this study. Manual operation was designed to compare the performance of the presented robot-assisted system. The real-time force curves show outstanding advantages of robot-assisted operation in improving the controllability and stability of needle insertion process by comparing manual operation. The statistics of maximum force and average force further demonstrates robot-assisted operation causes less oscillation. The difference of liver deformation created by manual operation and robot-assisted operation is very low, 1 mm for average deformation and 2 mm for maximum deformation. To conclude, the presented robot-assisted system can improve placement accuracy of needle by stably control insertion process.

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

    Agalgaonkar, Yashodhan P.; Hammerstrom, Donald J.

    The Pacific Northwest Smart Grid Demonstration (PNWSGD) was a smart grid technology performance evaluation project that included multiple U.S. states and cooperation from multiple electric utilities in the northwest region. One of the local objectives for the project was to achieve improved distribution system reliability. Toward this end, some PNWSGD utilities automated their distribution systems, including the application of fault detection, isolation, and restoration and advanced metering infrastructure. In light of this investment, a major challenge was to establish a correlation between implementation of these smart grid technologies and actual improvements of distribution system reliability. This paper proposes using Welch’smore » t-test to objectively determine and quantify whether distribution system reliability is improving over time. The proposed methodology is generic, and it can be implemented by any utility after calculation of the standard reliability indices. The effectiveness of the proposed hypothesis testing approach is demonstrated through comprehensive practical results. It is believed that wider adoption of the proposed approach can help utilities to evaluate a realistic long-term performance of smart grid technologies.« less

  8. The MiPACQ Clinical Question Answering System

    PubMed Central

    Cairns, Brian L.; Nielsen, Rodney D.; Masanz, James J.; Martin, James H.; Palmer, Martha S.; Ward, Wayne H.; Savova, Guergana K.

    2011-01-01

    The Multi-source Integrated Platform for Answering Clinical Questions (MiPACQ) is a QA pipeline that integrates a variety of information retrieval and natural language processing systems into an extensible question answering system. We present the system’s architecture and an evaluation of MiPACQ on a human-annotated evaluation dataset based on the Medpedia health and medical encyclopedia. Compared with our baseline information retrieval system, the MiPACQ rule-based system demonstrates 84% improvement in Precision at One and the MiPACQ machine-learning-based system demonstrates 134% improvement. Other performance metrics including mean reciprocal rank and area under the precision/recall curves also showed significant improvement, validating the effectiveness of the MiPACQ design and implementation. PMID:22195068

  9. The MiPACQ clinical question answering system.

    PubMed

    Cairns, Brian L; Nielsen, Rodney D; Masanz, James J; Martin, James H; Palmer, Martha S; Ward, Wayne H; Savova, Guergana K

    2011-01-01

    The Multi-source Integrated Platform for Answering Clinical Questions (MiPACQ) is a QA pipeline that integrates a variety of information retrieval and natural language processing systems into an extensible question answering system. We present the system's architecture and an evaluation of MiPACQ on a human-annotated evaluation dataset based on the Medpedia health and medical encyclopedia. Compared with our baseline information retrieval system, the MiPACQ rule-based system demonstrates 84% improvement in Precision at One and the MiPACQ machine-learning-based system demonstrates 134% improvement. Other performance metrics including mean reciprocal rank and area under the precision/recall curves also showed significant improvement, validating the effectiveness of the MiPACQ design and implementation.

  10. Improved measurement linearity and precision for AMCW time-of-flight range imaging cameras.

    PubMed

    Payne, Andrew D; Dorrington, Adrian A; Cree, Michael J; Carnegie, Dale A

    2010-08-10

    Time-of-flight range imaging systems utilizing the amplitude modulated continuous wave (AMCW) technique often suffer from measurement nonlinearity due to the presence of aliased harmonics within the amplitude modulation signals. Typically a calibration is performed to correct these errors. We demonstrate an alternative phase encoding approach that attenuates the harmonics during the sampling process, thereby improving measurement linearity in the raw measurements. This mitigates the need to measure the system's response or calibrate for environmental changes. In conjunction with improved linearity, we demonstrate that measurement precision can also be increased by reducing the duty cycle of the amplitude modulated illumination source (while maintaining overall illumination power).

  11. Optimisation of Healthcare Contracts: Tensions Between Standardisation and Innovation

    PubMed Central

    Mikkers, Misja; Ryan, Padhraig

    2016-01-01

    An important determinant of health system performance is contracting. Providers often respond to financial incentives, despite the ethical underpinnings of medicine, and payers can craft contracts to influence performance. Yet contracting is highly imperfect in both single-payer and multi-payer health systems. Arguably, in a competitive, multi-payer environment, contractual innovation may occur more rapidly than in a single-payer system. This innovation in contract design could enhance performance. However, contractual innovation often fails to improve performance as payer incentives are misaligned with public policy objectives. Numerous countries seek to improve healthcare contracts, but thus far no health system has demonstrably crafted the necessary blend of incentives to stimulate optimal contracting. PMID:26927400

  12. Constructing an adaptive care model for the management of disease-related symptoms throughout the course of multiple sclerosis--performance improvement CME.

    PubMed

    Miller, Aaron E; Cohen, Bruce A; Krieger, Stephen C; Markowitz, Clyde E; Mattson, David H; Tselentis, Helen N

    2014-01-01

    Symptom management remains a challenging clinical aspect of MS. To design a performance improvement continuing medical education (PI CME) activity for better clinical management of multiple sclerosis (MS)-related depression, fatigue, mobility impairment/falls, and spasticity. Ten volunteer MS centers participated in a three-stage PI CME model: A) baseline assessment; B) practice improvement CME intervention; C) reassessment. Expert faculty developed performance measures and activity intervention tools. Designated MS center champions reviewed patient charts and entered data into an online database. Stage C data were collected eight weeks after implementation of the intervention and compared with Stage A baseline data to measure change in performance. Aggregate data from the 10 participating MS centers (405 patient charts) revealed performance improvements in the assessment of all four MS-related symptoms. Statistically significant improvements were found in the documented assessment of mobility impairment/falls (p=0.003) and spasticity (p<0.001). For documentation of care plans, statistically significant improvements were reported for fatigue (p=0.007) and mobility impairment/falls (p=0.040); non-significant changes were noted for depression and spasticity. Our PI CME interventions demonstrated performance improvement in the management of MS-related symptoms. This PI CME model (available at www.achlpicme.org/ms/toolkit) offers a new perspective on enhancing symptom management in patients with MS.

  13. Surface Engineering of ITO Substrates to Improve the Memory Performance of an Asymmetric Conjugated Molecule with a Side Chain.

    PubMed

    Hou, Xiang; Cheng, Xue-Feng; Xiao, Xin; He, Jing-Hui; Xu, Qing-Feng; Li, Hua; Li, Na-Jun; Chen, Dong-Yun; Lu, Jian-Mei

    2017-09-05

    Organic multilevel random resistive access memory (RRAM) devices with an electrode/organic layer/electrode sandwich-like structure suffer from poor reproducibility, such as low effective ternary device yields and a wide threshold voltage distribution, and improvements through organic material renovation are rather limited. In contrast, engineering of the electrode surfaces rather than molecule design has been demonstrated to boost the performance of organic electronics effectively. Herein, we introduce surface engineering into organic multilevel RRAMs to enhance their ternary memory performance. A new asymmetric conjugated molecule composed of phenothiazine and malononitrile with a side chain (PTZ-PTZO-CN) was fabricated in an indium tin oxide (ITO)/PTZ-PTZO-CN/Al sandwich-like memory device. Modification of the ITO substrate with a phosphonic acid (PA) prior to device fabrication increased the ternary device yield (the ratio of effective ternary device) and narrowed the threshold voltage distribution. The crystallinity analysis revealed that PTZ-PTZO-CN grown on untreated ITO crystallized into two phases. After the surface engineering of ITO, this crystalline ambiguity was eliminated and a sole crystal phase was obtained that was the same as in the powder state. The unified crystal structure and improved grain mosaicity resulted in a lower threshold voltage and, therefore, a higher ternary device yield. Our result demonstrated that PA modification also improved the memory performance of an asymmetric conjugated molecule with a side chain. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Development of a 10 Ah, Prismatic, Lithium-Ion Cell for NASA/GSFC

    NASA Technical Reports Server (NTRS)

    Stein, Brian; Baker, John W.; George, Douglas S.; Isaacs, Nathan D.; Shah, Pinakin M.; Rao, Gopalakrishna M.; Day, John H. (Technical Monitor)

    2001-01-01

    MSA's 10 Ah Li-ion cell is a rugged design suitable for the stringent requirements of aerospace applications. Eighteen cells demonstrate consistent cycling performance over a wide range of rates and temperatures. The cell passes qualification requirements for vibration survivability technology improvements at MSA continue to enhance cell performance.

  15. Implications of Key Performance Indicator Issues in Ontario Universities Explored

    ERIC Educational Resources Information Center

    Chan, Vivian

    2015-01-01

    Since 1998, the Ministry of Training, Colleges and Universities in Ontario, Canada, has required that data on specific key performance indicators (KPIs) be made public by its publicly funded universities. The information is intended to be used by universities to demonstrate their achievements, to improve their programmes and services, and to…

  16. Demonstrating the Financial Benefit of Human Resource Development: Status and Update on the Theory and Practice.

    ERIC Educational Resources Information Center

    Swanson, Richard A.

    1998-01-01

    A research review identified findings about the financial analysis method, forecasting of the financial benefits of human resource development (HRD), and recent financial analysis research: (1) HRD embedded in a performance improvement framework yielded high return on investment; and (2) HRD interventions focused on performance variables forecast…

  17. How Does Exercise Benefit Performance on Cognitive Tests in Primary-School Pupils?

    ERIC Educational Resources Information Center

    Hill, Liam J. B.; Williams, Justin H. G.; Aucott, Lorna; Thomson, Jenny; Mon-Williams, Mark

    2011-01-01

    Aim: We have previously demonstrated improved cognitive performance after a classroom-based exercise regime. In this study, we examined the reproducibility of this effect in a more socio-economically diverse sample and also investigated whether cognitive benefits of exercise were moderated by body mass index (BMI) or symptoms of…

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

    Steiner, Myles A; Perl, Emmett; Simon, John D

    We demonstrate dual junction (Al)GaInP/GaAs solar cells that are designed to operate at 400 degrees C and 1000X concentration in a hybrid photovoltaic-solar thermal concentrator system. The cells have a front metallization and anti-reflection coating that are stable under 400 degrees C operation. We show how the cell performance degrades with increasing aluminum compositions in the top cell. Our best cell is a GaInP/GaAs tandem that demonstrated 15+/-1% efficiency at 400 degrees C over a concentration range of 300-1000 suns, with several pathways to improved performance.

  19. Adaptive inertial shock-absorber

    NASA Astrophysics Data System (ADS)

    Faraj, Rami; Holnicki-Szulc, Jan; Knap, Lech; Seńko, Jarosław

    2016-03-01

    This paper introduces and discusses a new concept of impact absorption by means of impact energy management and storage in dedicated rotating inertial discs. The effectiveness of the concept is demonstrated in a selected case-study involving spinning management, a recently developed novel impact-absorber. A specific control technique performed on this device is demonstrated to be the main source of significant improvement in the overall efficiency of impact damping process. The influence of various parameters on the performance of the shock-absorber is investigated. Design and manufacturing challenges and directions of further research are formulated.

  20. Effects of Pilates on muscle strength, postural balance and quality of life of older adults: a randomized, controlled, clinical trial

    PubMed Central

    Campos de Oliveira, Laís; Gonçalves de Oliveira, Raphael; Pires-Oliveira, Deise Aparecida de Almeida

    2015-01-01

    [Purpose] The aim of the present study was to determine the effects of Pilates on lower leg strength, postural balance and the health-related quality of life (HRQoL) of older adults. [Subjects and Methods] Thirty-two older adults were randomly allocated either to the experimental group (EG, n = 16; mean age, 63.62 ± 1.02 years), which performed two sessions of Pilates per week for 12 weeks, or to the control group (CG, n = 16; mean age, 64.21 ± 0.80), which performed two sessions of static stretching per week for 12 weeks. The following evaluations were performed before and after the interventions: isokinetic torque of knee extensors and flexors at 300°/s, the Timed Up and Go (TUG) test, the Berg Balance Scale, and the Health Survey assessment (SF-36). [Results] In the intra-group analysis, the EG demonstrated significant improvement in all variables. In the inter-group analysis, the EG demonstrated significant improvement in most variables. [Conclusion] Pilates exercises led to significant improvement in isokinetic torque of the knee extensors and flexors, postural balance and aspects of the health-related quality of life of older adults. PMID:25931749

  1. Development of a full-scale transmission testing procedure to evaluate advanced lubricants

    NASA Technical Reports Server (NTRS)

    Lewicki, David G.; Decker, Harry J.; Shimski, John T.

    1992-01-01

    Experimental tests were performed on the OH-58A helicopter main rotor transmission in the NASA Lewis 500-hp Helicopter Transmission Test Stand. The testing was part of a joint Navy/NASA/Army lubrication program. The objective of the program was to develop a separate lubricant for gearboxes and demonstrate an improved performance in life and load-carrying capacity. The goal of the experiments was to develop a testing procedure to fail certain transmission components using a MIL-L-23699 base reference oil, then run identical tests with improved lubricants and demonstrate performance. The tests were directed at failing components that the Navy has had problems with due to marginal lubrication. These failures included mast shaft bearing micropitting, sun gear and planet bearing fatigue, and spiral bevel gear scoring. A variety of tests were performed and over 900 hours of total run time accumulated for these tests. Some success was achieved in developing a testing procedure to produce sun gear and planet bearing fatigue failures. Only marginal success was achieved in producing mast shaft bearing micropitting and spiral bevel gear scoring.

  2. High performance polymer solar cells with as-prepared zirconium acetylacetonate film as cathode buffer layer

    PubMed Central

    Tan, Zhan'ao; Li, Shusheng; Wang, Fuzhi; Qian, Deping; Lin, Jun; Hou, Jianhui; Li, Yongfang

    2014-01-01

    Low-work-function active metals are commonly used as cathode in polymer solar cells (PSCs), but sensitivity of the active metals towards moisture and oxygen results in poor stability of the devices. Therefore, solution-proceessable and stable cathode buffer layer is of great importance for the application of PSCs. Here we demonstrate high performance PSCs by employing as-prepared zirconium acetylacetonate (a-ZrAcac) film spin-cast from its ethanol solution as cathode buffer layer. The PSCs based on a low bandgap polymer PBDTBDD as donor and PC60BM as acceptor with a-ZrAcac/Al cathode demonstrated an average power conversion efficiency (PCE) of 8.75% which is significantly improved than that of the devices with traditional Ca/Al cathode. The improved photovoltaic performance is benefitted from the decreased series resistance and enhanced light harvest of the PSCs with the a-ZrAcac/Al cathode. The results indicate that a-ZrAcac is a promising high performance cathode buffer layer for fabricating large area flexible PSCs. PMID:24732976

  3. beta-Blockade used in precision sports: effect on pistol shooting performance.

    PubMed

    Kruse, P; Ladefoged, J; Nielsen, U; Paulev, P E; Sørensen, J P

    1986-08-01

    In a double-blind cross-over study of 33 marksmen (standard pistol, 25 m) the adrenergic beta 1-receptor blocker, metoprolol, was compared to placebo. Metoprolol obviously improved the pistol shooting performance compared with placebo. Shooting improved by 13.4% of possible improvement (i.e., 600 points minus actual points obtained) as an average (SE = 4%, 2P less than 0.002). The most skilled athletes demonstrated the clearest metoprolol improvement. We found no correlation between the shooting improvement and changes in the cardiovascular variables (i.e., changes of heart rate and systolic blood pressure) and no correlation to the estimated maximum O2 uptake. The shooting improvement is an effect of metoprolol on hand tremor. Emotional increase of heart rate and systolic blood pressure seem to be a beta 1-receptor phenomenon.

  4. Balanced scorecards for performance management.

    PubMed

    Park, Eun-Jun; Huber, Diane L

    2007-01-01

    Nurse administrators who manage nursing case management programs are challenged to demonstrate the improved quality of patient care and financial outcomes to their organization that result from such programs. This article introduces the balanced scorecard and discusses its benefits and practical concerns for adopting the scorecard. The balanced scorecard is a useful performance management tool used to both evaluate and direct case management performance in meeting organizational missions and strategies.

  5. Increased neuromuscular consistency in gait and balance after partnered, dance-based rehabilitation in Parkinson's disease.

    PubMed

    Allen, Jessica L; McKay, J Lucas; Sawers, Andrew; Hackney, Madeleine E; Ting, Lena H

    2017-07-01

    Here we examined changes in muscle coordination associated with improved motor performance after partnered, dance-based rehabilitation in individuals with mild to moderate idiopathic Parkinson's disease. Using motor module (a.k.a. muscle synergy) analysis, we identified changes in the modular control of overground walking and standing reactive balance that accompanied clinically meaningful improvements in behavioral measures of balance, gait, and disease symptoms after 3 wk of daily Adapted Tango classes. In contrast to previous studies that revealed a positive association between motor module number and motor performance, none of the six participants in this pilot study increased motor module number despite improvements in behavioral measures of balance and gait performance. Instead, motor modules were more consistently recruited and distinctly organized immediately after rehabilitation, suggesting more reliable motor output. Furthermore, the pool of motor modules shared between walking and reactive balance increased after rehabilitation, suggesting greater generalizability of motor module function across tasks. Our work is the first to show that motor module distinctness, consistency, and generalizability are more sensitive to improvements in gait and balance function after short-term rehabilitation than motor module number. Moreover, as similar differences in motor module distinctness, consistency, and generalizability have been demonstrated previously in healthy young adults with and without long-term motor training, our work suggests commonalities in the structure of muscle coordination associated with differences in motor performance across the spectrum from motor impairment to expertise. NEW & NOTEWORTHY We demonstrate changes in neuromuscular control of gait and balance in individuals with Parkinson's disease after short-term, dance-based rehabilitation. Our work is the first to show that motor module distinctness, consistency, and generalizability across gait and balance are more sensitive than motor module number to improvements in motor performance following short-term rehabilitation. Our results indicate commonalities in muscle coordination improvements associated with motor skill reacquisition due to rehabilitation and motor skill acquisition in healthy individuals. Copyright © 2017 the American Physiological Society.

  6. Assessing methods of enhancing older driver performance.

    DOT National Transportation Integrated Search

    2013-05-01

    Research has demonstrated improvements in neuropsychological measuresfollowing participation in : cognitive training programs in normal aging individuals (Ball, et al., 2002; Ball, Edwards, & Ross, 2007; : Willis, et al., 2006; Wolinsky, et al., 2006...

  7. Interdisciplinary Residential Treatment of Posttraumatic Stress Disorder and Traumatic Brain Injury: Effects on Symptom Severity and Occupational Performance and Satisfaction

    PubMed Central

    Speicher, Sarah M.; Walter, Kristen H.

    2014-01-01

    OBJECTIVE. This study examined outcomes of an 8-wk residential treatment program for veterans with posttraumatic stress disorder (PTSD) and a history of traumatic brain injury (TBI). METHOD. Twenty-six veterans completed the Canadian Occupational Performance Measure, Clinician-Administered PTSD Scale, Beck Depression Inventory–2nd Edition, and PTSD Checklist before and after treatment. RESULTS. Veterans demonstrated significant improvements in occupational performance and satisfaction with their performance, as well as in PTSD and depression symptom severity after residential PTSD/TBI treatment. Additionally, improvements in occupational performance and satisfaction were associated with decreases in depression symptom severity. CONCLUSION. Although preliminary, results suggest that veterans with PTSD and a history of TBI experienced significant decreases in PTSD and depression symptom severity and improvement in self-perception of performance and satisfaction in problematic occupational areas. Changes in occupational areas and depression symptom severity were related, highlighting the importance of interdisciplinary treatment. PMID:25005504

  8. The American Society for Clinical Pathology resident in-service examination: does resident performance provide insight into the effectiveness of clinical pathology education?

    PubMed

    McKenna, Barbara J

    2007-06-01

    The resident in-service examination in pathology is an in-training exercise that is taken by virtually all pathology residents in the United States as well as by some participants in Canada, Ireland, and Lebanon. Although all of the anatomic pathology topics in the examination, with only one exception-forensic pathology, show significant improvement in scores over the 4 years of residency training, three areas of clinical pathology training (laboratory administration, clinical chemistry, and microbiology) show significantly lower improvement in performance over the years of residency training. By contrast, transfusion medicine, hematopathology and the special topics section of the examination all demonstrate improved performance by residents over time. While the reason behind these differences must remain speculative at this time, these findings suggest that measures to improve effectiveness in clinical pathology training might be suggested by examining the differences between residency training practices between higher and lower performing areas of clinical pathology.

  9. Prior experience, antioxidants, and mitochondrial cofactors improve cognitive function in aged beagles.

    PubMed

    Ikeda-Douglas, Candace J; Zicker, Steven C; Estrada, Jimena; Jewell, Dennis E; Milgram, Norton W

    2004-01-01

    Results of this study support the free-radical theory of aging and demonstrated that providing higher levels of vitamin E in food resulted in higher serum vitamin E concentrations and improved performance on landmark-discrimination tasks in aged dogs. Factors other than vitamin E also contributed to the response but remain undefined.

  10. Overall aspects of Bt in forest service cooperative gypsy moth suppression projects

    Treesearch

    Noel F. Schneeberger

    1985-01-01

    Improvements in Bt performance and cost, coupled with public concerns over human health risks have elevated Bt to a viable alternative to chemical insecticides. Operational use of Bt in recent years has demonstrated that while foliage protection can generally be achieved in most situations, gypsy moth population reduction cannot. Efforts are needed to improve Bt...

  11. RXIO: Design and implementation of high performance RDMA-capable GridFTP

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

    Tian, Yuan; Yu, Weikuan; Vetter, Jeffrey S.

    2011-12-21

    For its low-latency, high bandwidth, and low CPU utilization, Remote Direct Memory Access (RDMA) has established itself as an effective data movement technology in many networking environments. However, the transport protocols of grid run-time systems, such as GridFTP in Globus, are not yet capable of utilizing RDMA. In this study, we examine the architecture of GridFTP for the feasibility of enabling RDMA. An RDMA-capable XIO (RXIO) framework is designed and implemented to extend its XIO system and match the characteristics of RDMA. Our experimental results demonstrate that RDMA can significantly improve the performance of GridFTP, reducing the latency by 32%more » and increasing the bandwidth by more than three times. In achieving such performance improvements, RDMA dramatically cuts down CPU utilization of GridFTP clients and servers. In conclusion, these results demonstrate that RXIO can effectively exploit the benefits of RDMA for GridFTP. It offers a good prototype to further leverage GridFTP on wide-area RDMA networks.« less

  12. Improved GaSb-based quantum well laser performance through metamorphic growth on GaAs substrates

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

    Richardson, Christopher J. K., E-mail: richardson@lps.umd.edu; He, Lei; Apiratikul, Paveen

    The promise of the metamorphic growth paradigm is to enable design freedom of the substrate selection criteria beyond current choices that are limited by lattice matching requirements. A demonstration of this emerging degree of freedom is reported here by directly comparing identical laser structures grown both pseudomorphically on a GaSb substrate and metamorphically on a GaAs substrate. Improved thermal performance of the metamorphic laser material enables a higher output power before thermal roll-over begins. These performance gains are demonstrated in minimally processed gain-guided broad-area type-I lasers emitting close to 2-μm wavelengths and mounted p-side up. Continuous wave measurements at roommore » temperature yield a T{sub 0} of 145 K and peak output power of 192 mW from metamorphic lasers, compared to a T{sub 0} of 96 K and peak output power of 164 mW from identical lasers grown pseudomorphically on GaSb.« less

  13. Adaptive learning and control for MIMO system based on adaptive dynamic programming.

    PubMed

    Fu, Jian; He, Haibo; Zhou, Xinmin

    2011-07-01

    Adaptive dynamic programming (ADP) is a promising research field for design of intelligent controllers, which can both learn on-the-fly and exhibit optimal behavior. Over the past decades, several generations of ADP design have been proposed in the literature, which have demonstrated many successful applications in various benchmarks and industrial applications. While many of the existing researches focus on multiple-inputs-single-output system with steepest descent search, in this paper we investigate a generalized multiple-input-multiple-output (GMIMO) ADP design for online learning and control, which is more applicable to a wide range of practical real-world applications. Furthermore, an improved weight-updating algorithm based on recursive Levenberg-Marquardt methods is presented and embodied in the GMIMO approach to improve its performance. Finally, we test the performance of this approach based on a practical complex system, namely, the learning and control of the tension and height of the looper system in a hot strip mill. Experimental results demonstrate that the proposed approach can achieve effective and robust performance.

  14. Implementation of a Thick-Film Composite Li-Ion Microcathode Using Carbon Nanotubes as the Conductive Filler

    NASA Technical Reports Server (NTRS)

    Lin, Qian; Harb, John N.

    2004-01-01

    This paper describes the development of a thick-film microcathode for use in Li-ion microbatteries in order to provide increased power and energy per area. These cathodes take advantage of a composite porous electrode structure, utilizing carbon nanotubes (CNT) as the conductive filler. The use of carbon nanotubes was found to significantly reduce the measured resistance of the electrodes, increase active material accessibility, and improve electrode performance. In particular, the cycling and power performance of the thick-film cathodes was significantly improved, and the need for compression was eliminated. Cathode thickness and CNT content were optimized to maximize capacity and power performance. Power capability of >50 mW/sq cm (17 mA/sq cm) with discharge capacity of >0.17 mAh/sq cm was demonstrated. The feasibility of fabricating thick-film microcathodes capable of providing the power and capacity needed for use in autonomous microsensor systems was also demonstrated.

  15. A Global Evaluation of Coral Reef Management Performance: Are MPAs Producing Conservation and Socio-Economic Improvements?

    NASA Astrophysics Data System (ADS)

    Hargreaves-Allen, Venetia; Mourato, Susana; Milner-Gulland, Eleanor Jane

    2011-04-01

    There is a consensus that Marine Protected Area (MPA) performance needs regular evaluation against clear criteria, incorporating counterfactual comparisons of ecological and socio-economic performance. However, these evaluations are scarce at the global level. We compiled self-reports from managers and researchers of 78 coral reef-based MPAs world-wide, on the conservation and welfare improvements that their MPAs provide. We developed a suite of performance measures including fulfilment of design and management criteria, achievement of aims, the cessation of banned or destructive activities, change in threats, and measurable ecological and socio-economic changes in outcomes, which we evaluated with respect to the MPA's age, geographical location and main aims. The sample was found to be broadly representative of MPAs generally, and suggests that many MPAs do not achieve certain fundamental aims including improvements in coral cover over time (in 25% of MPAs), and conflict reduction (in 25%). However, the large majority demonstrated improvements in terms of slowing coral loss, reducing destructive uses and increasing tourism and local employment, despite many being small, underfunded and facing multiple large scale threats beyond the control of managers. However spatial comparisons suggest that in some regions MPAs are simply mirroring outside changes, with demonstrates the importance of testing for additionality. MPA benefits do not appear to increase linearly over time. In combination with other management efforts and regulations, especially those relating to large scale threat reduction and targeted fisheries and conflict resolution instruments, MPAs are an important tool to achieve coral reef conservation globally. Given greater resources and changes which incorporate best available science, such as larger MPAs and no-take areas, networks and reduced user pressure, it is likely that performance could further be enhanced. Performance evaluation should test for the generation of additional ecological and socio-economic improvements over time and compared to unmanaged areas as part of an adaptive management regime.

  16. High-fidelity hybrid simulation of allergic emergencies demonstrates improved preparedness for office emergencies in pediatric allergy clinics.

    PubMed

    Kennedy, Joshua L; Jones, Stacie M; Porter, Nicholas; White, Marjorie L; Gephardt, Grace; Hill, Travis; Cantrell, Mary; Nick, Todd G; Melguizo, Maria; Smith, Chris; Boateng, Beatrice A; Perry, Tamara T; Scurlock, Amy M; Thompson, Tonya M

    2013-01-01

    Simulation models that used high-fidelity mannequins have shown promise in medical education, particularly for cases in which the event is uncommon. Allergy physicians encounter emergencies in their offices, and these can be the source of much trepidation. To determine if case-based simulations with high-fidelity mannequins are effective in teaching and retention of emergency management team skills. Allergy clinics were invited to Arkansas Children's Hospital Pediatric Understanding and Learning through Simulation Education center for a 1-day workshop to evaluate skills concerning the management of allergic emergencies. A Clinical Emergency Preparedness Team Performance Evaluation was developed to evaluate the competence of teams in several areas: leadership and/or role clarity, closed-loop communication, team support, situational awareness, and scenario-specific skills. Four cases, which focus on common allergic emergencies, were simulated by using high-fidelity mannequins and standardized patients. Teams were evaluated by multiple reviewers by using video recording and standardized scoring. Ten to 12 months after initial training, an unannounced in situ case was performed to determine retention of the skills training. Clinics showed significant improvements for role clarity, teamwork, situational awareness, and scenario-specific skills during the 1-day workshop (all P < .003). Follow-up in situ scenarios 10-12 months later demonstrated retention of skills training at both clinics (all P ≤ .004). Clinical Emergency Preparedness Team Performance Evaluation scores demonstrated improved team management skills with simulation training in office emergencies. Significant recall of team emergency management skills was demonstrated months after the initial training. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  17. An Improved Perturb and Observe Algorithm for Photovoltaic Motion Carriers

    NASA Astrophysics Data System (ADS)

    Peng, Lele; Xu, Wei; Li, Liming; Zheng, Shubin

    2018-03-01

    An improved perturbation and observation algorithm for photovoltaic motion carriers is proposed in this paper. The model of the proposed algorithm is given by using Lambert W function and tangent error method. Moreover, by using matlab and experiment of photovoltaic system, the tracking performance of the proposed algorithm is tested. And the results demonstrate that the improved algorithm has fast tracking speed and high efficiency. Furthermore, the energy conversion efficiency by the improved method has increased by nearly 8.2%.

  18. Developing pharmacy student communication skills through role-playing and active learning.

    PubMed

    Luiz Adrian, Julie Ann; Zeszotarski, Paula; Ma, Carolyn

    2015-04-25

    To evaluate the impact on pharmacy students of a communication course, which used role-playing to develop active-learning skills. Students role-playing pharmacists in patient care scenarios were critiqued by students and pharmacist faculty members. Grading was performed using the rubric inspired by Bruce Berger's Communication Skills for Pharmacists. Written skills were evaluated using student written critique questionnaires. Students completed precourse and postcourse self-assessment surveys. Preceptor evaluations were analyzed for course impact. Students demonstrated improvement in oral skills based on role-play scores (45.87/50) after practice sessions. The average score based on the student questionnaire was 9.31/10. Gain was demonstrated in all defined course objectives. Impact on introductory pharmacy practice experience (IPPE) communication objectives was insignificant. Student evaluations for course and teaching strategy reflected a high average. Study results demonstrated improvement in oral and written communication skills that may help improve interprofessional teamwork between pharmacists and other health care providers.

  19. Improving learning performance with happiness by interactive scenarios.

    PubMed

    Chuang, Chi-Hung; Chen, Ying-Nong; Tsai, Luo-Wei; Lee, Chun-Chieh; Tsai, Hsin-Chun

    2014-01-01

    Recently, digital learning has attracted a lot of researchers to improve the problems of learning carelessness, low learning ability, lack of concentration, and difficulties in comprehending the logic of math. In this study, a digital learning system based on Kinect somatosensory system is proposed to make children and teenagers happily learn in the course of the games and improve the learning performance. We propose two interactive geometry and puzzle games. The proposed somatosensory games can make learners feel curious and raise their motivation to find solutions for boring problems via abundant physical expressions and interactive operations. The players are asked to select particular operation by gestures and physical expressions within a certain time. By doing so, the learners can feel the fun of game playing and train their logic ability before they are aware. Experimental results demonstrate that the proposed somatosensory system can effectively improve the students' learning performance.

  20. Considerably improved photovoltaic performance of carbon nanotube-based solar cells using metal oxide layers.

    PubMed

    Wang, Feijiu; Kozawa, Daichi; Miyauchi, Yuhei; Hiraoka, Kazushi; Mouri, Shinichiro; Ohno, Yutaka; Matsuda, Kazunari

    2015-02-18

    Carbon nanotube-based solar cells have been extensively studied from the perspective of potential application. Here we demonstrated a significant improvement of the carbon nanotube solar cells by the use of metal oxide layers for efficient carrier transport. The metal oxides also serve as an antireflection layer and an efficient carrier dopant, leading to a reduction in the loss of the incident solar light and an increase in the photocurrent, respectively. As a consequence, the photovoltaic performance of both p-single-walled carbon nanotube (SWNT)/n-Si and n-SWNT/p-Si heterojunction solar cells using MoOx and ZnO layers is improved, resulting in very high photovoltaic conversion efficiencies of 17.0 and 4.0%, respectively. These findings regarding the use of metal oxides as multifunctional layers suggest that metal oxide layers could improve the performance of various electronic devices based on carbon nanotubes.

  1. Improving Learning Performance with Happiness by Interactive Scenarios

    PubMed Central

    Chuang, Chi-Hung; Chen, Ying-Nong; Tsai, Luo-Wei; Lee, Chun-Chieh; Tsai, Hsin-Chun

    2014-01-01

    Recently, digital learning has attracted a lot of researchers to improve the problems of learning carelessness, low learning ability, lack of concentration, and difficulties in comprehending the logic of math. In this study, a digital learning system based on Kinect somatosensory system is proposed to make children and teenagers happily learn in the course of the games and improve the learning performance. We propose two interactive geometry and puzzle games. The proposed somatosensory games can make learners feel curious and raise their motivation to find solutions for boring problems via abundant physical expressions and interactive operations. The players are asked to select particular operation by gestures and physical expressions within a certain time. By doing so, the learners can feel the fun of game playing and train their logic ability before they are aware. Experimental results demonstrate that the proposed somatosensory system can effectively improve the students' learning performance. PMID:24558331

  2. Considerably improved photovoltaic performance of carbon nanotube-based solar cells using metal oxide layers

    NASA Astrophysics Data System (ADS)

    Wang, Feijiu; Kozawa, Daichi; Miyauchi, Yuhei; Hiraoka, Kazushi; Mouri, Shinichiro; Ohno, Yutaka; Matsuda, Kazunari

    2015-02-01

    Carbon nanotube-based solar cells have been extensively studied from the perspective of potential application. Here we demonstrated a significant improvement of the carbon nanotube solar cells by the use of metal oxide layers for efficient carrier transport. The metal oxides also serve as an antireflection layer and an efficient carrier dopant, leading to a reduction in the loss of the incident solar light and an increase in the photocurrent, respectively. As a consequence, the photovoltaic performance of both p-single-walled carbon nanotube (SWNT)/n-Si and n-SWNT/p-Si heterojunction solar cells using MoOx and ZnO layers is improved, resulting in very high photovoltaic conversion efficiencies of 17.0 and 4.0%, respectively. These findings regarding the use of metal oxides as multifunctional layers suggest that metal oxide layers could improve the performance of various electronic devices based on carbon nanotubes.

  3. The 30-kW ammonia arcjet technology

    NASA Technical Reports Server (NTRS)

    Deininger, W. D.; Chopra, A.; Pivirotto, T. J.; Goodfellow, K. D.; Barnett, J. W.

    1990-01-01

    The technical results are summarized of a 30 kW class ammonia propellant arcjet technology program. Evaluation of previous arcjet thruster performance, including materials analysis of used thruster components, led to the design of an arcjet with improved performance and thermal characteristics. Tests of the new engine demonstrated that engine performance is relatively insensitive to cathode tip geometry. Other data suggested a maximum sustainable arc length for a given thruster configuration, beyond which the arc may reconfigure in a destructive manner. A flow controller calibration error was identified. This error caused previously reported values of specific impulse and thrust efficiency to be 20 percent higher than the real values. Corrected arcjet performance data are given. Duration tests of 413 and 252 hours, and several tests 100 hours in duration, were performed. The cathode tip erosion rate increased with increasing arc current. Elimination of power source ripple did not affect cathode tip whisker growth. Results of arcjet modeling, diagnostic development and mission analyses are also discussed. The 30 kW ammonia arcjet may now be considered ready for development for a flight demonstration, but widespread application of 30 kW class arcjet will require improved efficiency and lifetime.

  4. RASSP signal processing architectures

    NASA Astrophysics Data System (ADS)

    Shirley, Fred; Bassett, Bob; Letellier, J. P.

    1995-06-01

    The rapid prototyping of application specific signal processors (RASSP) program is an ARPA/tri-service effort to dramatically improve the process by which complex digital systems, particularly embedded signal processors, are specified, designed, documented, manufactured, and supported. The domain of embedded signal processing was chosen because it is important to a variety of military and commercial applications as well as for the challenge it presents in terms of complexity and performance demands. The principal effort is being performed by two major contractors, Lockheed Sanders (Nashua, NH) and Martin Marietta (Camden, NJ). For both, improvements in methodology are to be exercised and refined through the performance of individual 'Demonstration' efforts. The Lockheed Sanders' Demonstration effort is to develop an infrared search and track (IRST) processor. In addition, both contractors' results are being measured by a series of externally administered (by Lincoln Labs) six-month Benchmark programs that measure process improvement as a function of time. The first two Benchmark programs are designing and implementing a synthetic aperture radar (SAR) processor. Our demonstration team is using commercially available VME modules from Mercury Computer to assemble a multiprocessor system scalable from one to hundreds of Intel i860 microprocessors. Custom modules for the sensor interface and display driver are also being developed. This system implements either proprietary or Navy owned algorithms to perform the compute-intensive IRST function in real time in an avionics environment. Our Benchmark team is designing custom modules using commercially available processor ship sets, communication submodules, and reconfigurable logic devices. One of the modules contains multiple vector processors optimized for fast Fourier transform processing. Another module is a fiberoptic interface that accepts high-rate input data from the sensors and provides video-rate output data to a display. This paper discusses the impact of simulation on choosing signal processing algorithms and architectures, drawing from the experiences of the Demonstration and Benchmark inter-company teams at Lockhhed Sanders, Motorola, Hughes, and ISX.

  5. Improving the performance of galloping micro-power generators by passively manipulating the trailing edge

    NASA Astrophysics Data System (ADS)

    Noel, J.; Yadav, R.; Li, G.; Daqaq, M. F.

    2018-02-01

    Recent trends in distributed sensing networks have generated significant interest in the design of scalable micro-power generators. One such device exploits the galloping oscillations of a prism to harness energy from a moving fluid. Performance of galloping harvester's depends on the flow patterns around the prism, which, in turn, depend on its geometry and the Reynolds number of the flow. In this letter, we demonstrate that the useful range of the galloping instability can be extended by attaching a rigid splitter plate to the rear face of the prism. The plate provides a secondary flow reattachment point, which serves to improve the oscillation amplitude and power output of the generator. Experimental results demonstrate as much as 67% power enhancement for some prism geometries and a significant reduction in the cut-in wind speed of the generator.

  6. Decision-feedback detection strategy for nonlinear frequency-division multiplexing

    NASA Astrophysics Data System (ADS)

    Civelli, Stella; Forestieri, Enrico; Secondini, Marco

    2018-04-01

    By exploiting a causality property of the nonlinear Fourier transform, a novel decision-feedback detection strategy for nonlinear frequency-division multiplexing (NFDM) systems is introduced. The performance of the proposed strategy is investigated both by simulations and by theoretical bounds and approximations, showing that it achieves a considerable performance improvement compared to previously adopted techniques in terms of Q-factor. The obtained improvement demonstrates that, by tailoring the detection strategy to the peculiar properties of the nonlinear Fourier transform, it is possible to boost the performance of NFDM systems and overcome current limitations imposed by the use of more conventional detection techniques suitable for the linear regime.

  7. Improved Performance of High Areal Density Indirect Drive Implosions at the National Ignition Facility using a Four-Shock Adiabat Shaped Drive

    DOE PAGES

    Casey, D. T.; Milovich, J. L.; Smalyuk, V. A.; ...

    2015-09-01

    Hydrodynamic instabilities can cause capsule defects and other perturbations to grow and degrade implosion performance in ignition experiments at the National Ignition Facility (NIF). Here, we show the first experimental demonstration that a strong unsupported first shock in indirect drive implosions at the NIF reduces ablation front instability growth leading to a 3 to 10 times higher yield with fuel ρR > 1 g=cm 2. This work shows the importance of ablation front instability growth during the National Ignition Campaign and may provide a path to improved performance at the high compression necessary for ignition.

  8. Reliable B Cell Epitope Predictions: Impacts of Method Development and Improved Benchmarking

    PubMed Central

    Kringelum, Jens Vindahl; Lundegaard, Claus; Lund, Ole; Nielsen, Morten

    2012-01-01

    The interaction between antibodies and antigens is one of the most important immune system mechanisms for clearing infectious organisms from the host. Antibodies bind to antigens at sites referred to as B-cell epitopes. Identification of the exact location of B-cell epitopes is essential in several biomedical applications such as; rational vaccine design, development of disease diagnostics and immunotherapeutics. However, experimental mapping of epitopes is resource intensive making in silico methods an appealing complementary approach. To date, the reported performance of methods for in silico mapping of B-cell epitopes has been moderate. Several issues regarding the evaluation data sets may however have led to the performance values being underestimated: Rarely, all potential epitopes have been mapped on an antigen, and antibodies are generally raised against the antigen in a given biological context not against the antigen monomer. Improper dealing with these aspects leads to many artificial false positive predictions and hence to incorrect low performance values. To demonstrate the impact of proper benchmark definitions, we here present an updated version of the DiscoTope method incorporating a novel spatial neighborhood definition and half-sphere exposure as surface measure. Compared to other state-of-the-art prediction methods, Discotope-2.0 displayed improved performance both in cross-validation and in independent evaluations. Using DiscoTope-2.0, we assessed the impact on performance when using proper benchmark definitions. For 13 proteins in the training data set where sufficient biological information was available to make a proper benchmark redefinition, the average AUC performance was improved from 0.791 to 0.824. Similarly, the average AUC performance on an independent evaluation data set improved from 0.712 to 0.727. Our results thus demonstrate that given proper benchmark definitions, B-cell epitope prediction methods achieve highly significant predictive performances suggesting these tools to be a powerful asset in rational epitope discovery. The updated version of DiscoTope is available at www.cbs.dtu.dk/services/DiscoTope-2.0. PMID:23300419

  9. Can Youth with Autism Spectrum Disorder Use Virtual Reality Driving Simulation Training to Evaluate and Improve Driving Performance? An Exploratory Study.

    PubMed

    Cox, Daniel J; Brown, Timothy; Ross, Veerle; Moncrief, Matthew; Schmitt, Rose; Gaffney, Gary; Reeve, Ron

    2017-08-01

    Investigate how novice drivers with autism spectrum disorder (ASD) differ from experienced drivers and whether virtual reality driving simulation training (VRDST) improves ASD driving performance. 51 novice ASD drivers (mean age 17.96 years, 78% male) were randomized to routine training (RT) or one of three types of VRDST (8-12 sessions). All participants followed DMV behind-the-wheel training guidelines for earning a driver's license. Participants were assessed pre- and post-training for driving-specific executive function (EF) abilities and tactical driving skills. ASD drivers showed worse baseline EF and driving skills than experienced drivers. At post-assessment, VRDST significantly improved driving and EF performance over RT. This study demonstrated feasibility and potential efficacy of VRDST for novice ASD drivers.

  10. Citicoline Treatment Improves Measures of Impulsivity and Task Performance in Chronic Marijuana Smokers: A Pilot BOLD fMRI Study

    PubMed Central

    Gruber, Staci A.; Sagar, Kelly A.; Dahlgren, Mary Kathryn; Gonenç, Atilla; Conn, Nina A.; Winer, Jeffrey P.; Penetar, David; Lukas, Scott E.

    2015-01-01

    Objective Citicoline is an endogenous nucleotide that has historically been used to treat stroke, traumatic brain injury, and cognitive dysfunction. Research has also shown that citicoline treatment is associated with improved cognitive performance in substance-abusing populations. We hypothesized that marijuana (MJ) smokers who received citicoline would demonstrate improvement in cognitive performance as well as increased neural efficiency during tasks of cognitive control relative to those who received placebo. Method The current study tested this hypothesis by examining the effects of citicoline in treatment-seeking chronic MJ smokers. In an 8-week double-blind, placebo-controlled study, 19 MJ smokers were randomly assigned via a double-blind procedure to the citicoline (8 Males, 2 Females) or placebo group (9 Males, 0 Females). All participants completed fMRI scanning at baseline and after 8 weeks of treatment during two cognitive measures of inhibitory processing, the Multi Source Interference Test (MSIT) and Stroop Color Word Test, and also completed the Barratt Impulsiveness Scale (BIS-11), a self-report measure of impulsivity. Results Following the 8 week trial, MJ smokers treated with citicoline demonstrated significantly lower levels of behavioral impulsivity, improved task accuracy on both the MSIT and Stroop tasks, and exhibited significantly different patterns of brain activation relative to baseline levels and relative to those who received placebo. Conclusions Findings suggest that citicoline may facilitate the treatment of MJ use disorders by improving the cognitive skills necessary to fully engage in comprehensive treatment programs. PMID:26658924

  11. Performance Degradation Assessment of Rolling Element Bearings using Improved Fuzzy Entropy

    NASA Astrophysics Data System (ADS)

    Zhu, Keheng; Jiang, Xiaohui; Chen, Liang; Li, Haolin

    2017-10-01

    Rolling element bearings are an important unit in the rotating machines, and their performance degradation assessment is the basis of condition-based maintenance. Targeting the non-linear dynamic characteristics of faulty signals of rolling element bearings, a bearing performance degradation assessment approach based on improved fuzzy entropy (FuzzyEn) is proposed in this paper. FuzzyEn has less dependence on data length and achieves more freedom of parameter selection and more robustness to noise. However, it neglects the global trend of the signal when calculating similarity degree of two vectors, and thus cannot reflect the running state of the rolling element bearings accurately. Based on this consideration, the algorithm of FuzzyEn is improved in this paper and the improved FuzzyEn is utilized as an indicator for bearing performance degradation evaluation. The vibration data from run-to-failure test of rolling element bearings are used to validate the proposed method. The experimental results demonstrate that, compared with the traditional kurtosis and root mean square, the proposed method can detect the incipient fault in advance and can reflect the whole performance degradation process more clearly.

  12. Decimated Input Ensembles for Improved Generalization

    NASA Technical Reports Server (NTRS)

    Tumer, Kagan; Oza, Nikunj C.; Norvig, Peter (Technical Monitor)

    1999-01-01

    Recently, many researchers have demonstrated that using classifier ensembles (e.g., averaging the outputs of multiple classifiers before reaching a classification decision) leads to improved performance for many difficult generalization problems. However, in many domains there are serious impediments to such "turnkey" classification accuracy improvements. Most notable among these is the deleterious effect of highly correlated classifiers on the ensemble performance. One particular solution to this problem is generating "new" training sets by sampling the original one. However, with finite number of patterns, this causes a reduction in the training patterns each classifier sees, often resulting in considerably worsened generalization performance (particularly for high dimensional data domains) for each individual classifier. Generally, this drop in the accuracy of the individual classifier performance more than offsets any potential gains due to combining, unless diversity among classifiers is actively promoted. In this work, we introduce a method that: (1) reduces the correlation among the classifiers; (2) reduces the dimensionality of the data, thus lessening the impact of the 'curse of dimensionality'; and (3) improves the classification performance of the ensemble.

  13. Frequent video game players resist perceptual interference.

    PubMed

    Berard, Aaron V; Cain, Matthew S; Watanabe, Takeo; Sasaki, Yuka

    2015-01-01

    Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT), a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning.

  14. The Student-to-Student Chemistry Initiative: Training High School Students To Perform Chemistry Demonstration Programs for Elementary School Students

    NASA Astrophysics Data System (ADS)

    Voegel, Phillip D.; Quashnock, Kathryn A.; Heil, Katrina M.

    2004-05-01

    The Student-to-Student Chemistry Initiative is an outreach program started in the fall of 2001 at Midwestern State University (MSU). The oncampus program trains high school science students to perform a series of chemistry demonstrations and subsequently provides kits containing necessary supplies and reagents for the high school students to perform demonstration programs at elementary schools. The program focuses on improving student perception of science. The program's impact on high school student perception is evaluated through statistical analysis of paired preparticipation and postparticipation surveys. The surveys focus on four areas of student perception: general attitude toward science, interest in careers in science, science awareness, and interest in attending MSU for postsecondary education. Increased scores were observed in all evaluation areas including a statistically significant increase in science awareness following participation.

  15. The Relationship between N-Back Performance and Matrix Reasoning--Implications for Training and Transfer

    ERIC Educational Resources Information Center

    Jaeggi, Susanne M.; Studer-Luethi, Barbara; Buschkuehl, Martin; Su, Yi-Fen; Jonides, John; Perrig, Walter J.

    2010-01-01

    We have previously demonstrated that training on a dual n-back task results in improvements in fluid intelligence ("Gf") as measured by matrix reasoning tasks. Here, we explored the underlying mechanisms of this transfer effect in two studies, and we evaluated the transfer potential of a single n-back task. In the first study, we demonstrated that…

  16. Demonstration of differential phase-shift keying demodulation at 10 Gbit/s optimal fiber Bragg grating filters.

    PubMed

    Gatti, Davide; Galzerano, Gianluca; Laporta, Paolo; Longhi, Stefano; Janner, Davide; Guglierame, Andrea; Belmonte, Michele

    2008-07-01

    Optimal demodulation of differential phase-shift keying signals at 10 Gbit/s is experimentally demonstrated using a specially designed structured fiber Bragg grating composed by Fabry-Perot coupled cavities. Bit-error-rate measurements show that, as compared with a conventional Gaussian-shaped filter, our demodulator gives approximately 2.8 dB performance improvement.

  17. Improvements upon the "Colorful Cobalt Catalysis" Demonstration and Evidence for the Presence of an Autocatalytic Mechanism

    ERIC Educational Resources Information Center

    Wright, Stephen W.

    2010-01-01

    The oxidation of potassium sodium tartrate by hydrogen peroxide catalyzed by cobalt(II) chloride is a favorite lecture demonstration. I present conditions under which this experiment may be performed without need for 30% hydrogen peroxide and without need for controlled heating or any heating of the reaction mixture. I further show that this…

  18. Monolayer-Mediated Growth of Organic Semiconductor Films with Improved Device Performance.

    PubMed

    Huang, Lizhen; Hu, Xiaorong; Chi, Lifeng

    2015-09-15

    Increased interest in wearable and smart electronics is driving numerous research works on organic electronics. The control of film growth and patterning is of great importance when targeting high-performance organic semiconductor devices. In this Feature Article, we summarize our recent work focusing on the growth, crystallization, and device operation of organic semiconductors intermediated by ultrathin organic films (in most cases, only a monolayer). The site-selective growth, modified crystallization and morphology, and improved device performance of organic semiconductor films are demonstrated with the help of the inducing layers, including patterned and uniform Langmuir-Blodgett monolayers, crystalline ultrathin organic films, and self-assembled polymer brush films. The introduction of the inducing layers could dramatically change the diffusion of the organic semiconductors on the surface and the interactions between the active layer with the inducing layer, leading to improved aggregation/crystallization behavior and device performance.

  19. Advanced Lithium-ion Batteries with High Specific Energy and Improved Safety for Nasa's Missions

    NASA Technical Reports Server (NTRS)

    West, William; Smart, Marshall; Soler, Jess; Krause, Charlie; Hwang, Constanza; Bugga, Ratnakumar

    2012-01-01

    High Energy Materials ( Cathodes, anodes and high voltage and safe electrolyte are required to meet the needs of the future space missions. A. Cathodes: The layered layered composites of of Li2MnO3 and LiMO2 are promising Power capability of the materials, however requires further improvement. Suitable morphology is critical for good performance and high tap (packing) density. Surface coatings help in the interfacial kinetics and stability. B. Electrolytes: Small additions of Flame Retardant Additives improves flammability without affecting performance (Rate and cycle life). 1.0 M in EC+EMC+TPP was shown to have good performance against the high voltage cathode; Performance demonstrated in large capacity prototype MCMB- LiNiCoO2 Cells. Formulations with higher proportions are looking promising. Still requires further validation through abuse tests (e.g., on 18650 cells).

  20. QUAD+ BWR Fuel Assembly demonstration program at Browns Ferry plant

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

    Doshi, P.K.; Mayhue, L.T.; Robert, J.T.

    1984-04-01

    The QUAD+ fuel assembly is an improved BWR fuel assembly designed and manufactured by Westinghouse Electric Corporation. The design features a water cross separating four fuel minibundles in an integral channel. A demonstration program for this fuel design is planned for late 1984 in cycle 6 of Browns Ferry 2, a TVA plant. Objectives for the design of the QUAD+ demonstration assemblies are compatibility in performance and transparency in safety analysis with the feed fuel. These objectives are met. Inspections of the QUAD+ demonstration assemblies are planned at each refueling outage.

  1. Edge geometry effects on resonance response of electroplated cylindrical Ni/PZT/Ni magnetoelectric composites

    NASA Astrophysics Data System (ADS)

    Yakubov, Vladislav; Xu, Lirong; Volinsky, Alex A.; Qiao, Lijie; Pan, De'an

    2017-08-01

    Trilayer Ni/PZT/Ni cylindrical magnetoelectric (ME) composites were prepared by electrodeposition, a process, which creates sub-millimeter raised edges due to current concentration near sharp points. The ME response in both axial and vertical modes was measured with the edges, with only outer edges removed, and with both outer and inner edges removed. The ME voltage coefficient improved at resonance by 40% and 147% without the edges in the vertical and axial modes, respectively. The observed improvements in three different samples were only present at the ME resonance and no changes were detected outside of the ME resonance. Mechanical quality factor at resonance also improved with no effect on the resonant frequency. Experimentally demonstrated minor geometry changes resulted in substantial ME improvement at resonant frequency. This study demonstrates device performance optimization. The observed effects have been attributed to improved vibrations in terms of decreased damping coefficient and enhanced vibration amplitude at resonance.

  2. [Computer-assisted cardiovascular disease management: better implementation of care but no improvement in clinical outcomes].

    PubMed

    de Wit, Niek J

    2012-01-01

    Computer support is considered by many to be a promising strategy for improving healthcare interventions, especially in the management of chronic diseases. So far, however, evidence of the effectiveness of ICT support in healthcare is limited. Recently, computer-supported cardiovascular disease management was compared with usual care during an RCT comprised of 1100 primary care patients. This trial demonstrated that neither the clinical outcome nor the cardiovascular morbidity rate improved, even though management of the risk factors improved over 1 year of follow-up. The pragmatic design of the RCT in daily general practice may have restricted implementing the computer support, and may also have hampered the evaluation of the cardiovascular effects. The results demonstrate that although computer support may help improve the performance of disease management, its impact on disease outcomes is questionable. ICT innovations in healthcare require rigorous investigative evaluation before their implementation in daily practice can be justified.

  3. High-performance and environmentally stable planar heterojunction perovskite solar cells based on a solution-processed copper-doped nickel oxide hole-transporting layer.

    PubMed

    Kim, Jong H; Liang, Po-Wei; Williams, Spencer T; Cho, Namchul; Chueh, Chu-Chen; Glaz, Micah S; Ginger, David S; Jen, Alex K-Y

    2015-01-27

    An effective approach to significantly increase the electrical conductivity of a NiOx hole-transporting layer (HTL) to achieve high-efficiency planar heterojunction perovskite solar cells is demonstrated. Perovskite solar cells based on using Cu-doped NiOx HTL show a remarkably improved power conversion efficiency up to 15.40% due to the improved electrical conductivity and enhanced perovskite film quality. General applicability of Cu-doped NiOx to larger bandgap perovskites is also demonstrated in this study. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Albrecht H. Mayer

    Asea Brown Boveri (ABB) has completed its technology based program. The results developed under Work Breakdown Structure (WBS) 8, concentrated on technology development and demonstration have been partially implemented in newer turbine designs. A significant improvement in heat rate and power output has been demonstrated. ABB will use the knowledge gained to further improve the efficiency of its Advanced Cycle System, which has been developed and introduced into the marked out side ABB's Advanced Turbine System (ATS) activities. The technology will lead to a power plant design that meets the ATS performance goals of over 60% plant efficiency, decreased electricitymore » costs to consumers and lowest emissions.« less

  5. Electrochemical characterization of nanodimensional metal oxide materials

    NASA Astrophysics Data System (ADS)

    Tang, Paul Enle

    Energy storage devices have become a bottleneck in performance improvements for portable electronics. This research seeks to answer basic science questions that may lead to the necessary improvements. First, this work demonstrates that insertion of multivalent ions into vanadium oxide greatly exceeds the storage capacity of materials presently used. Second, this work demonstrates that potassium ferrate exhibits a uniquely large pseudocapacitive effect. This effect can be used to great advantage when high power density and high energy density are required. Lastly, this work proposes a model of pseudocapacitance that has a greater descriptive power than that of previous models.

  6. A Study to Determine the Best Way for Letterman Army Medical Center to Comply with the 1981 JCAH (Joint Commission on Accreditation of Hospitals) Quality Assurance Standard

    DTIC Science & Technology

    1980-08-01

    follow-up action taken would be prima facie evidence of the program’s positive impact on patient care/ clinical performance. Direct and indirect...demonstration of improved patient care/clinical performance must be shown. Prima facie evidence 57 of such improvement would include a summary of identified...even in relation to the seven other HSC medical cen- ters, because of the following reasons: - Active duty patients cannot- claim or file a law- suit

  7. Nature-Inspired Capillary-Driven Welding Process for Boosting Metal-Oxide Nanofiber Electronics.

    PubMed

    Meng, You; Lou, Kaihua; Qi, Rui; Guo, Zidong; Shin, Byoungchul; Liu, Guoxia; Shan, Fukai

    2018-06-20

    Recently, semiconducting nanofiber networks (NFNs) have been considered as one of the most promising platforms for large-area and low-cost electronics applications. However, the high contact resistance among stacking nanofibers remained to be a major challenge, leading to poor device performance and parasitic energy consumption. In this report, a controllable welding technique for NFNs was successfully demonstrated via a bioinspired capillary-driven process. The interfiber connections were well-achieved via a cooperative concept, combining localized capillary condensation and curvature-induced surface diffusion. With the improvements of the interfiber connections, the welded NFNs exhibited enhanced mechanical property and high electrical performance. The field-effect transistors (FETs) based on the welded Hf-doped In 2 O 3 (InHfO) NFNs were demonstrated for the first time. Meanwhile, the mechanisms involved in the grain-boundary modulation for polycrystalline metal-oxide nanofibers were discussed. When the high-k ZrO x dielectric thin films were integrated into the FETs, the field-effect mobility and operating voltage were further improved to be 25 cm 2 V -1 s -1 and 3 V, respectively. This is one of the best device performances among the reported nanofibers-based FETs. These results demonstrated the potencies of the capillary-driven welding process and grain-boundary modulation mechanism for metal-oxide NFNs, which could be applicable for high-performance, large-scale, and low-power functional electronics.

  8. The effect of within-session instruction on lumbopelvic motion during a lower limb movement in people with and people without low back pain

    PubMed Central

    Scholtes, Sara A.; Norton, Barbara J.; Lang, Catherine E.; Van Dillen, Linda R.

    2010-01-01

    The purpose of the current study was to examine how effectively people with and people without low back pain (LBP) modify lumbopelvic motion during a limb movement test. Nineteen subjects with LBP and 20 subjects without LBP participated. Kinematic data were collected while subjects performed active hip lateral rotation (HLR) in prone. Subjects completed trials (1) using their natural method (Natural condition) of performing HLR, and (2) following standardized instructions to modify lumbopelvic motion while performing HLR (Modified condition). Variables of interest included (1) the amount of HLR completed prior to the start of lumbopelvic motion, and (2) the maximum amount of lumbopelvic motion demonstrated during HLR. Compared to the Natural Condition, all subjects improved their performance during the Modified condition by (1) completing a greater amount of HLR prior to the start of lumbopelvic motion, and (2) demonstrating less lumbopelvic motion (P<0.01 for all comparisons). There was a tendency for people without LBP to demonstrate a greater difference in maximal lumbopelvic rotation between the Natural and Modified conditions (P=0.07). In conclusion, people are able to modify lumbopelvic motion following instruction. Further study is needed to determine if people without LBP improve lumbopelvic motion following instruction to a greater extent than people with LBP. PMID:20627798

  9. Application of the Athlete's Performance Passport for Doping Control: A Case Report.

    PubMed

    Iljukov, Sergei; Bermon, Stephane; Schumacher, Yorck O

    2018-01-01

    The efficient use of testing resources is a key issue in the fight against doping. The longitudinal tracking of sporting performances to identify unusual improvements possibly caused by doping, so-called "athlete's performance passport" (APP) is a new concept to improve targeted anti-doping testing. In fact, unusual performances by an athlete would trigger a more thorough testing program. In the present case report, performance data is modeled using the critical power concept for a group of athletes based on their past performances. By these means, an athlete with unusual deviations from his predicted performances was identified. Subsequent target testing using blood testing and the athlete biological passport resulted in an anti-doping rule violation procedure and suspension of the athlete. This case demonstrates the feasibility of the APP approach where athlete's performance is monitored and might serve as an example for the practical implementation of the method.

  10. Application of the Athlete's Performance Passport for Doping Control: A Case Report

    PubMed Central

    Iljukov, Sergei; Bermon, Stephane; Schumacher, Yorck O.

    2018-01-01

    The efficient use of testing resources is a key issue in the fight against doping. The longitudinal tracking of sporting performances to identify unusual improvements possibly caused by doping, so-called “athlete's performance passport” (APP) is a new concept to improve targeted anti-doping testing. In fact, unusual performances by an athlete would trigger a more thorough testing program. In the present case report, performance data is modeled using the critical power concept for a group of athletes based on their past performances. By these means, an athlete with unusual deviations from his predicted performances was identified. Subsequent target testing using blood testing and the athlete biological passport resulted in an anti-doping rule violation procedure and suspension of the athlete. This case demonstrates the feasibility of the APP approach where athlete's performance is monitored and might serve as an example for the practical implementation of the method. PMID:29651247

  11. Materials, device, and interface engineering to improve polymer-based solar cells

    NASA Astrophysics Data System (ADS)

    Hau, Steven Kin

    The continued depletion of fossil fuel resources has lead to the rise in energy production costs which has lead to the search for an economically viable alternative energy source. One alternative of particular interest is solar energy. A promising alternative to inorganic materials is organic semiconductor polymer solar cells due to their advantages of being cheaper, light weight, flexible and made into large areas by roll-to-roll processing. In this dissertation, an integrated approach is taken to improve the overall performance of polymer-based solar cells by the development of new polymer materials, device architectures, and interface engineering of the contacts between layers. First, a new class of metallated conjugated polymers is explored as potential solar cell materials. Systematic modifications to the molecular units on the main chain of amorphous metallated Pt-polymers show a correlation that improving charge carrier mobility also improves solar cell performance leading to mobilities as high as 1 x 10-2 cm2/V·s and efficiencies as high as 4.1%. Second, an inverted device architecture using a more air stable electrode (Ag) is demonstrated to improve the ambient stability of unencapsulated P3HT:PCBM devices showing over 80% efficiency retention after 40 days of exposure. To further demonstrate the potential for roll-to-roll processing of polymer solar cells, solution processed Ag-nanoparticles were used to replace the vacuum deposited Ag anode electrode for inverted solar cells showing efficiencies as high as 3%. In addition, solution processed polymer based electrodes were demonstrated as a replacement to the expensive and brittle indium tin oxide showing efficiencies of 3% on flexible substrate solar cells. Third, interface engineering of the n-type (high temperature sol-gel processed TiO2 or ZnO, low temperature processed ZnO nanoparticles) electron selective metal oxide contacts in inverted solar cells with self-assembled monolayers (SAM) show improved device performance. Modifying the n-type layer in inverted cells with C60-SAMs containing different anchoring groups leads to an improvement in photocurrent density and fill factor leading to efficiencies as high as 4.9%.

  12. Atomic Layer Deposition of Al2O3-Ga2O3 Alloy Coatings for Li[Ni0.5Mn0.3Co0.2]O2 Cathode to Improve Rate Performance in Li-Ion Battery.

    PubMed

    Laskar, Masihhur R; Jackson, David H K; Guan, Yingxin; Xu, Shenzhen; Fang, Shuyu; Dreibelbis, Mark; Mahanthappa, Mahesh K; Morgan, Dane; Hamers, Robert J; Kuech, Thomas F

    2016-04-27

    Metal oxide coatings can improve the electrochemical stability of cathodes and hence, their cycle-life in rechargeable batteries. However, such coatings often impose an additional electrical and ionic transport resistance to cathode surfaces leading to poor charge-discharge capacity at high C-rates. Here, a mixed oxide (Al2O3)1-x(Ga2O3)x alloy coating, prepared via atomic layer deposition (ALD), on Li[Ni0.5Mn0.3Co0.2]O2 (NMC) cathodes is developed that has increased electron conductivity and demonstrated an improved rate performance in comparison to uncoated NMC. A "co-pulsing" ALD technique was used which allows intimate and controlled ternary mixing of deposited film to obtain nanometer-thick mixed oxide coatings. Co-pulsing allows for independent control over film composition and thickness in contrast to separate sequential pulsing of the metal sources. (Al2O3)1-x(Ga2O3)x alloy coatings were demonstrated to improve the cycle life of the battery. Cycle tests show that increasing Al-content in alloy coatings increases capacity retention; whereas a mixture of compositions near (Al2O3)0.5(Ga2O3)0.5 was found to produce the optimal rate performance.

  13. The Relationship Between Asymmetry and Athletic Performance: A Critical Review.

    PubMed

    Maloney, Sean J

    2018-05-08

    Maloney, SJ. The relationship between asymmetry and athletic performance: A critical review. J Strength Cond Res XX(X): 000-000, 2018-Symmetry may be defined as the quality to demonstrate an exact correspondence of size, shape, and form when split along a given axis. Although it has been widely asserted that the bilateral asymmetries are detrimental to athletic performance, research does not wholly support such an association. Moreover, the research rarely seeks to distinguish between different types of bilateral asymmetry. Fluctuating asymmetries describe bilateral differences in anthropometric attributes, such as nostril width and ear size, and are thought to represent the developmental stability of an organism. There is evidence to suggest that fluctuating asymmetries may be related to impaired athletic performance, although contradictory findings have been reported. Sporting asymmetries is a term that may better describe bilateral differences in parameters, such as force output or jump height. These asymmetries are likely to be a function of limb dominance and magnified by long-standing participation within sport. Sporting asymmetries do not seem to carry a clear influence on athletic performance measures. Given the vast discrepancy in the methodologies used by different investigations, further research is warranted. Recent investigations have demonstrated that training interventions can reduce sporting asymmetries and improve performance. However, studies have not sought to determine whether the influence of sporting asymmetry is independent of improvements in neuromuscular parameters. It may be hypothesized that the deficient (weaker) limb has a greater potential for adaptation in comparison to the strong limb and may demonstrate greater responsiveness to training.

  14. Do semantic contextual cues facilitate transfer learning from video in toddlers?

    PubMed Central

    Zimmermann, Laura; Moser, Alecia; Grenell, Amanda; Dickerson, Kelly; Yao, Qianwen; Gerhardstein, Peter; Barr, Rachel

    2015-01-01

    Young children typically demonstrate a transfer deficit, learning less from video than live presentations. Semantically meaningful context has been demonstrated to enhance learning in young children. We examined the effect of a semantically meaningful context on toddlers’ imitation performance. Two- and 2.5-year-olds participated in a puzzle imitation task to examine learning from either a live or televised model. The model demonstrated how to assemble a three-piece puzzle to make a fish or a boat, with the puzzle demonstration occurring against a semantically meaningful background context (ocean) or a yellow background (no context). Participants in the video condition performed significantly worse than participants in the live condition, demonstrating the typical transfer deficit effect. While the context helped improve overall levels of imitation, especially for the boat puzzle, only individual differences in the ability to self-generate a stimulus label were associated with a reduction in the transfer deficit. PMID:26029131

  15. Do semantic contextual cues facilitate transfer learning from video in toddlers?

    PubMed

    Zimmermann, Laura; Moser, Alecia; Grenell, Amanda; Dickerson, Kelly; Yao, Qianwen; Gerhardstein, Peter; Barr, Rachel

    2015-01-01

    Young children typically demonstrate a transfer deficit, learning less from video than live presentations. Semantically meaningful context has been demonstrated to enhance learning in young children. We examined the effect of a semantically meaningful context on toddlers' imitation performance. Two- and 2.5-year-olds participated in a puzzle imitation task to examine learning from either a live or televised model. The model demonstrated how to assemble a three-piece puzzle to make a fish or a boat, with the puzzle demonstration occurring against a semantically meaningful background context (ocean) or a yellow background (no context). Participants in the video condition performed significantly worse than participants in the live condition, demonstrating the typical transfer deficit effect. While the context helped improve overall levels of imitation, especially for the boat puzzle, only individual differences in the ability to self-generate a stimulus label were associated with a reduction in the transfer deficit.

  16. Shear lag sutures: Improved suture repair through the use of adhesives

    PubMed Central

    Linderman, Stephen W.; Kormpakis, Ioannis; Gelberman, Richard H.; Birman, Victor; Wegst, Ulrike G. K.; Genin, Guy M.; Thomopoulos, Stavros

    2015-01-01

    Suture materials and surgical knot tying techniques have improved dramatically since their first use over five millennia ago. However, the approach remains limited by the ability of the suture to transfer load to tissue at suture anchor points. Here, we predict that adhesive-coated sutures can improve mechanical load transfer beyond the range of performance of existing suture methods, thereby strengthening repairs and decreasing the risk of failure. The mechanical properties of suitable adhesives were identified using a shear lag model. Examination of the design space for an optimal adhesive demonstrated requirements for strong adhesion and low stiffness to maximize the strength of the adhesive-coated suture repair construct. To experimentally assess the model, we evaluated single strands of sutures coated with highly flexible cyanoacrylates (Loctite 4903 and 4902), cyanoacrylate (Loctite QuickTite Instant Adhesive Gel), rubber cement, rubber/gasket adhesive (1300 Scotch-Weld Neoprene High Performance Rubber & Gasket Adhesive), an albumin-glutaraldehyde adhesive (BioGlue), or poly(dopamine). As a clinically relevant proof-of-concept, cyanoacrylate-coated sutures were then used to perform a clinically relevant flexor digitorum tendon repair in cadaver tissue. The repair performed with adhesive-coated suture had significantly higher strength compared to the standard repair without adhesive. Notably, cyanoacrylate provides strong adhesion with high stiffness and brittle behavior, and is therefore not an ideal adhesive for enhancing suture repair. Nevertheless, the improvement in repair properties in a clinically relevant setting, even using a non-ideal adhesive, demonstrates the potential for the proposed approach to improve outcomes for treatments requiring suture fixation. Further study is necessary to develop a strongly adherent, compliant adhesive within the optimal design space described by the model. PMID:26022966

  17. Improved functionality of graphene and carbon nanotube hybrid foam architecture by UV-ozone treatment

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Ruiz, Isaac; Lee, Ilkeun; Zaera, Francisco; Ozkan, Mihrimah; Ozkan, Cengiz S.

    2015-04-01

    Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability.Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06795a

  18. Infrequent dream recall associated with low performance but high overnight improvement on mirror-tracing.

    PubMed

    Dumel, Gaëlle; Carr, Michelle; Marquis, Louis-Philippe; Blanchette-Carrière, Cloé; Paquette, Tyna; Nielsen, Tore

    2015-08-01

    Although sleep facilitates learning and memory, the roles of dreaming and habitual levels of recalling dreams remain unknown. This study examined if performance and overnight improvement on a rapid eye movement sleep-sensitive visuomotor task is associated differentially with habitually high or low dream recall frequency. As a relation between dream production and visuospatial skills has been demonstrated previously, one possibility is that frequency of dream recall will be linked to performance on visuomotor tasks such as the Mirror Tracing Task. We expected that habitually low dream recallers would perform more poorly on the Mirror Tracing Task than would high recallers and would show less task improvement following a night of sleep. Fifteen low and 20 high dream recallers slept one night each in the laboratory and performed the Mirror Tracing Task before and after sleep. Low recallers had overall worse baseline performance but a greater evening-to-morning improvement than did high recallers. Greater improvements in completion time in low recallers were associated with Stage 2 rather than rapid eye movement sleep. Findings support the separate notions that dreaming is related to visuomotor processes and that different levels of visuomotor skill engage different sleep- and dream-related consolidation mechanisms. © 2015 European Sleep Research Society.

  19. Rapid core measure improvement through a "business case for quality".

    PubMed

    Perlin, Jonathan B; Horner, Stephen J; Englebright, Jane D; Bracken, Richard M

    2014-01-01

    Incentives to improve performance are emerging as revenue or financial penalties are linked to the measured quality of service provided. The HCA "Getting to Green" program was designed to rapidly increase core measure performance scores. Program components included (1) the "business case for quality"-increased awareness of how quality drives financial performance; (2) continuous communication of clinical and financial performance data; and (3) evidence-based clinical protocols, incentives, and tools for process improvement. Improvement was measured by comparing systemwide rates of adherence to national quality measures for heart failure (HF), acute myocardial infarction (AMI), pneumonia (PN), and surgical care (SCIP) to rates from all facilities reporting to the Centers for Medicare and Medicaid Services (CMS). As of the second quarter of 2011, 70% of HCA total measure set composite scores were at or above the 90th percentile of CMS scores. A test of differences in regression coefficients between the CMS national average and the HCA average revealed significant differences for AMI (p = .001), HF (p = .012), PN (p < .001), and SCIP (p = .015). This program demonstrated that presentation of the financial implications of quality, transparency in performance data, and clearly defined goals could cultivate the desire to use improvement tools and resources to raise performance. © 2012 National Association for Healthcare Quality.

  20. Prediction of changes in memory performance by plasma homovanillic acid levels in clozapine-treated patients with schizophrenia.

    PubMed

    Sumiyoshi, Tomiki; Roy, A; Kim, C-H; Jayathilake, K; Lee, M A; Sumiyoshi, C; Meltzer, H Y

    2004-12-01

    Cognitive dysfunction in schizophrenia has been demonstrated to be dependent, in part, on dopaminergic activity. Clozapine has been found to improve some domains of cognition, including verbal memory, in patients with schizophrenia. This study tested the hypothesis that plasma homovanillic acid (pHVA) levels, a peripheral measure of central dopaminergic activity, would predict the change in memory performance in patients with schizophrenia treated with clozapine. Twenty-seven male patients with schizophrenia received clozapine treatment for 6 weeks. Verbal list learning (VLL)-Delayed Recall (VLL-DR), a test of secondary verbal memory, was administered before and after clozapine treatment. Blood samples to measure pHVA levels were collected at baseline. Baseline pHVA levels were negatively correlated with change in performance on VLL-DR; the lower baseline pHVA level was associated with greater improvement in performance on VLL-DR during treatment with clozapine. Baseline pHVA levels in subjects who showed improvement in verbal memory during clozapine treatment ( n=13) were significantly lower than those in subjects whose memory performance did not improve ( n=14). The results of this study indicate that baseline pHVA levels predict the ability of clozapine to improve memory performance in patients with schizophrenia.

  1. International Space Station Major Constituent Analyzer On-Orbit Performance

    NASA Technical Reports Server (NTRS)

    Gardner, Ben D.; Erwin, Phillip M.; Thoresen, Souzan; Granahan, John; Matty, Chris

    2012-01-01

    The Major Constituent Analyzer is a mass spectrometer based system that measures the major atmospheric constituents on the International Space Station. A number of limited-life components require periodic changeout, including the ORU 02 analyzer and the ORU 08 Verification Gas Assembly. Over the past two years, two ORU 02 analyzer assemblies have operated nominally while two others have experienced premature on-orbit failures. These failures as well as nominal performances demonstrate that ORU 02 performance remains a key determinant of MCA performance and logistical support. It can be shown that monitoring several key parameters can maximize the capacity to monitor ORU health and properly anticipate end of life. Improvements to ion pump operation and ion source tuning are expected to improve lifetime performance of the current ORU 02 design.

  2. Relative health performance in BRICS over the past 20 years: the winners and losers

    PubMed Central

    Petrie, Dennis

    2014-01-01

    Abstract Objective To determine whether the health performance of Brazil, the Russian Federation, India, China and South Africa – the countries known as BRICS – has kept in step with their economic development. Methods Reductions in age- and sex-specific mortality seen in each BRICS country between 1990 and 2011 were measured. These results were compared with those of the best-performing countries in the world and the best-performing countries with similar income levels. We estimated each country’s progress in reducing mortality and compared changes in that country’s mortality rates against other countries with similar mean incomes to examine changes in avoidable mortality. Findings The relative health performance of the five study countries differed markedly over the study period. Brazil demonstrated fairly even improvement in relative health performance across the different age and sex subgroups that we assessed. India’s improvement was more modest and more varied across the subgroups. South Africa and the Russian Federation exhibited large declines in health performance as well as large sex-specific inequalities in health. Although China’s levels of avoidable mortality decreased in absolute terms, the level of improvement appeared low in the context of China’s economic growth. Conclusion When evaluating a country’s health performance in terms of avoidable mortality, it is useful to compare that performance against the performance of other countries. Such comparison allows any country-specific improvements to be distinguished from general global improvements. PMID:24940013

  3. Selection for Surgical Training: An Evidence-Based Review.

    PubMed

    Schaverien, Mark V

    2016-01-01

    The predictive relationship between candidate selection criteria for surgical training programs and future performance during and at the completion of training has been investigated for several surgical specialties, however there is no interspecialty agreement regarding which selection criteria should be used. Better understanding the predictive reliability between factors at selection and future performance may help to optimize the process and lead to greater standardization of the surgical selection process. PubMed and Ovid MEDLINE databases were searched. Over 560 potentially relevant publications were identified using the search strategy and screened using the Cochrane Collaboration Data Extraction and Assessment Template. 57 studies met the inclusion criteria. Several selection criteria used in the traditional selection demonstrated inconsistent correlation with subsequent performance during and at the end of surgical training. The following selection criteria, however, demonstrated good predictive relationships with subsequent resident performance: USMLE examination scores, Letters of Recommendation (LOR) including the Medical Student Performance Evaluation (MSPE), academic performance during clinical clerkships, the interview process, displaying excellence in extracurricular activities, and the use of unadjusted rank lists. This systematic review supports that the current selection process needs to be further evaluated and improved. Multicenter studies using standardized outcome measures of success are now required to improve the reliability of the selection process to select the best trainees. Published by Elsevier Inc.

  4. Supplementation with macular carotenoids improves visual performance of transgenic mice.

    PubMed

    Li, Binxing; Rognon, Gregory T; Mattinson, Ty; Vachali, Preejith P; Gorusupudi, Aruna; Chang, Fu-Yen; Ranganathan, Arunkumar; Nelson, Kelly; George, Evan W; Frederick, Jeanne M; Bernstein, Paul S

    2018-07-01

    Carotenoid supplementation can improve human visual performance, but there is still no validated rodent model to test their effects on visual function in laboratory animals. We recently showed that mice deficient in β-carotene oxygenase 2 (BCO2) and/or β-carotene oxygenase 1 (BCO1) enzymes can accumulate carotenoids in their retinas, allowing us to investigate the effects of carotenoids on the visual performance of mice. Using OptoMotry, a device to measure visual function in rodents, we examined the effect of zeaxanthin, lutein, and β-carotene on visual performance of various BCO knockout mice. We then transgenically expressed the human zeaxanthin-binding protein GSTP1 (hGSTP1) in the rods of bco2 -/- mice to examine if delivering more zeaxanthin to retina will improve their visual function further. The visual performance of bco2 -/- mice fed with zeaxanthin or lutein was significantly improved relative to control mice fed with placebo beadlets. β-Carotene had no significant effect in bco2 -/- mice but modestly improved cone visual function of bco1 -/- mice. Expression of hGSTP1 in the rods of bco2 -/- mice resulted in a 40% increase of retinal zeaxanthin and further improvement of visual performance. This work demonstrates that these "macular pigment mice" may serve as animal models to study carotenoid function in the retina. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. The Role of Single Talker Acoustic Variation in Early Word Learning

    ERIC Educational Resources Information Center

    Galle, Marcus E.; Apfelbaum, Keith S.; McMurray, Bob

    2015-01-01

    Recent work has demonstrated that the addition of multiple talkers during habituation improves 14-month-olds' performance in the switch task (Rost & McMurray, 2009). While the authors suggest that this boost in performance is due to the increase in acoustic variability (Rost & McMurray, 2010), it is also possible that there is…

  6. A Learning Evaluation for an Immersive Virtual Laboratory for Technical Training Applied into a Welding Workshop

    ERIC Educational Resources Information Center

    Torres, Francisco; Neira Tovar, Leticia A.; del Rio, Marta Sylvia

    2017-01-01

    This study aims to explore the results of welding virtual training performance, designed using a learning model based on cognitive and usability techniques, applying an immersive concept focused on person attention. Moreover, it also intended to demonstrate that exits a moderating effect of performance improvement when the user experience is taken…

  7. Cultural Learning Context as It Relates to Efficacy and the Mathematics Performance of African-American Middle School Students

    ERIC Educational Resources Information Center

    Burrell, Jennifer O.

    2012-01-01

    Nearly 20 years of empirical work has demonstrated that cultural-asset focused learning environments can improve the academic performance of African-American students. One example is communal learning context, which shifts students' motivational primacy from the individual to the social group. Considering the critical role of efficacy beliefs in…

  8. LiFePO4 nanoparticles encapsulated in graphene nanoshells for high-performance lithium-ion battery cathodes.

    PubMed

    Fei, Huilong; Peng, Zhiwei; Yang, Yang; Li, Lei; Raji, Abdul-Rahman O; Samuel, Errol L G; Tour, James M

    2014-07-11

    LiFePO4 encapsulated in graphene nanoshells (LiFePO4@GNS) nanoparticles were synthesized by solid state reaction between graphene-coated Fe nanoparticles and LiH2PO4. The resulting nanocomposite was demonstrated to be a superior lithium-ion battery cathode with improved cycle and rate performances.

  9. Self-Explanation and Reading Strategy Training (SERT) Improves Low-Knowledge Students' Science Course Performance

    ERIC Educational Resources Information Center

    McNamara, Danielle S.

    2017-01-01

    This study demonstrates the generalization of previous laboratory results showing the benefits of self-explanation reading training (SERT) to college students' course exam performance. The participants were 265 students enrolled in an Introductory Biology course, 59 of whom were provided with SERT training. The results showed that SERT benefited…

  10. Self-Explanation and Reading Strategy Training (SERT) Improves Low-Knowledge Students' Science Course Performance

    ERIC Educational Resources Information Center

    McNamara, Danielle S.

    2017-01-01

    This study demonstrates the generalization of previous laboratory results showing the benefits of Self-Explanation Reading Training (SERT) to college students' course exam performance. The participants were 265 students enrolled in an Introductory Biology course, 59 of whom were provided with SERT. The results showed that SERT benefited students…

  11. Effects of Peer Mentors on Work-Related Performance of Adolescents with Behavioral and/or Learning Disabilities

    ERIC Educational Resources Information Center

    Westerlund, Debbie; Granucci, Elizabeth A.; Gamache, Peter; Clark, Hewitt B.

    2006-01-01

    Many young people with behavior disorders and/or learning disabilities need assistance in learning work-related tasks but want support that is minimally intrusive and nonstigmatizing. This study demonstrates the effectiveness and acceptability of using peer mentors as natural supports to assist in improving work-related student performance in a…

  12. Spacecraft utensil/hand cleansing fixture

    NASA Technical Reports Server (NTRS)

    Jonkoniec, T. G.

    1978-01-01

    A fixture which provides a means for a crewman to perform, in zero gravity, laboratory utensil/tool cleansing and personal hygiene functions such as handwashing, shaving, body wash, and teeth brushing is described. A prototype unit developed incorporating design improvements resulting from breadboard tests in a one gravity and zero gravity environment demonstrated the capability of performing the different cleansing functions.

  13. Severity of anxiety and work-related outcomes of patients with anxiety disorders.

    PubMed

    Erickson, Steven R; Guthrie, Sally; Vanetten-Lee, Michelle; Himle, Joseph; Hoffman, Jody; Santos, Susana F; Janeck, Amy S; Zivin, Kara; Abelson, James L

    2009-01-01

    This study examined associations between anxiety and work-related outcomes in an anxiety disorders clinic population, examining both pretreatment links and the impact of anxiety change over 12 weeks of treatment on work outcomes. Four validated instruments were used to also allow examination of their psychometric properties, with the goal of improving measurement of work-related quality of life in this population. Newly enrolled adult patients seeking treatment in a university-based anxiety clinic were administered four work performance measures: Work Limitations Questionnaire (WLQ), Work Productivity and Activity Impairment Questionnaire (WPAI), Endicott Work Productivity Scale (EWPS), and Functional Status Questionnaire Work Performance Scale (WPS). Anxiety severity was determined using the Beck Anxiety Inventory (BAI). The Clinical Global Impressions, Global Improvement Scale (CGI-I) was completed by patients to evaluate symptom change at a 12-week follow-up. Two severity groups (minimal/mild vs. moderate/severe, based on baseline BAI score) were compared to each other on work measures. Eighty-one patients provided complete baseline data. Anxiety severity groups did not differ in job type, time on job, job satisfaction, or job choice. Patients with greater anxiety generally showed lower work performance on all instruments. Job advancement was impaired for the moderate/severe group. The multi-item performance scales demonstrated better validity and internal consistency. The WLQ and the WPAI detected change with symptom improvement. Level of work performance was generally associated with severity of anxiety. Of the instruments tested, the WLQ and the WPAI questionnaire demonstrated acceptable validity and internal reliability.

  14. Acute Exercise Improves Motor Memory Consolidation in Preadolescent Children

    PubMed Central

    Lundbye-Jensen, Jesper; Skriver, Kasper; Nielsen, Jens B.; Roig, Marc

    2017-01-01

    Objective: The ability to acquire new motor skills is essential both during childhood and later in life. Recent studies have demonstrated that an acute bout of exercise can improve motor memory consolidation in adults. The objective of the present study was to investigate whether acute exercise protocols following motor skill practice in a school setting can also improve long-term retention of motor memory in preadolescent children. Methods: Seventy-seven pre-adolescent children (age 10.5 ± 0.75 (SD)) participated in the study. Prior to the main experiment age, BMI, fitness status and general physical activity level was assessed in all children and they were then randomly allocated to three groups. All children practiced a visuomotor tracking task followed by 20 min of rest (CON), high intensity intermittent floorball (FLB) or running (RUN) with comparable exercise intensity and duration for exercise groups. Delayed retention of motor memory was assessed 1 h, 24 h and 7 days after motor skill acquisition. Results: During skill acquisition, motor performance improved significantly to the immediate retention test with no differences between groups. One hour following skill acquisition, motor performance decreased significantly for RUN. Twenty-four hours following skill acquisition there was a tendency towards improved performance for FLB but no significant effects. Seven days after motor practice however, both FLB and RUN performed better when compared to their immediate retention test indicating significant offline gains. This effect was not observed for CON. In contrast, 7 days after motor practice, retention of motor memory was significantly better for FLB and RUN compared to CON. No differences were observed when comparing FLB and RUN. Conclusions: Acute intense intermittent exercise performed immediately after motor skill acquisition facilitates long-term motor memory in pre-adolescent children, presumably by promoting memory consolidation. The results also demonstrate that the effects can be accomplished in a school setting. The positive effect of both a team game (i.e., FLB) and running indicates that the observed memory improvements are determined to a larger extent by physiological factors rather than the types of movements performed during the exercise protocol. PMID:28473761

  15. Study of TiO2 particles size, dyes, and catalyst to improve the performance of DSSC

    NASA Astrophysics Data System (ADS)

    Saehana, Sahrul; Darsikin, Muslimin

    2016-02-01

    This study reports effort to improve performance of solar cells by using various natural dyes in dye-sensitized solar cell (DSSC). We applied three kind of natural dye, i.e, black rice dye, cactus dye and dragon fruit dye. We found that performance of DSSC which employ black rice dye was higher than other natural dyes. It is because the wider spectrum wavelength of black rice dyes. Its performance also compared with rhutenium dye (N719). Effect of TiO2 particle to DSSC performance was also investigated. It was concluded that smaller TiO2 particle size will increase the performance of DSSC solar cells. It was because the smaller particle size (high surface area) will load more dye. In addition, we also demonstrated the use of graphite from lead pencil as counter electrode.

  16. Slicing of Silicon into Sheet Material. Silicon Sheet Growth Development for the Large Area Silicon Sheet Task of the Low Cost Solar Array Project

    NASA Technical Reports Server (NTRS)

    Fleming, J. R.; Holden, S. C.; Wolfson, R. G.

    1979-01-01

    The use of multiblade slurry sawing to produce silicon wafers from ingots was investigated. The commercially available state of the art process was improved by 20% in terms of area of silicon wafers produced from an ingot. The process was improved 34% on an experimental basis. Economic analyses presented show that further improvements are necessary to approach the desired wafer costs, mostly reduction in expendable materials costs. Tests which indicate that such reduction is possible are included, although demonstration of such reduction was not completed. A new, large capacity saw was designed and tested. Performance comparable with current equipment (in terms of number of wafers/cm) was demonstrated.

  17. Impact of Breast Reader Assessment Strategy on mammographic radiologists' test reading performance.

    PubMed

    Suleiman, Wasfi I; Rawashdeh, Mohammad A; Lewis, Sarah J; McEntee, Mark F; Lee, Warwick; Tapia, Kriscia; Brennan, Patrick C

    2016-06-01

    The detection of breast cancer is somewhat limited by human factors, and thus there is a need to improve reader performance. This study assesses whether radiologists who regularly undertake the education in the form of the Breast Reader Assessment Strategy (BREAST) demonstrate any changes in mammography interpretation performance over time. In 2011, 2012 and 2013, 14 radiologists independently assessed a year-specific BREAST mammographic test-set. Radiologists read a different single test-set once each year, with each comprising 60 digital mammogram cases. Radiologists marked the location of suspected lesions without computer-aided diagnosis (CAD) and assigned a confidence rating of 2 for benign and 3-5 for malignant lesions. The mean sensitivity, specificity, location sensitivity, JAFROC FOM and ROC AUC were calculated. A Kruskal-Wallis test was used to compare the readings for the 14 radiologists across the 3 years. Wilcoxon signed rank test was used to assess comparison between pairs of years. Relationships between changes in performance and radiologist characteristics were examined using a Spearman's test. Significant increases were noted in mean sensitivity (P = 0.01), specificity (P = 0.01), location sensitivity (P = 0.001) and JAFROC FOM (P = 0.001) between 2011 and 2012. Between 2012 and 2013, significant improvements were noted in mean sensitivity (P = 0.003), specificity (P = 0.002), location sensitivity (P = 0.02), JAFROC FOM (P = 0.005) and ROC AUC (P = 0.008). No statistically significant correlations were shown between the levels of improvement and radiologists' characteristics. Radiologists' who undertake the BREAST programme demonstrate significant improvements in test-set performance during a 3-year period, highlighting the value of ongoing education through the use of test-set. © 2016 The Royal Australian and New Zealand College of Radiologists.

  18. Using spatialized sound cues in an auditorily rich environment

    NASA Astrophysics Data System (ADS)

    Brock, Derek; Ballas, James A.; Stroup, Janet L.; McClimens, Brian

    2004-05-01

    Previous Navy research has demonstrated that spatialized sound cues in an otherwise quiet setting are useful for directing attention and improving performance by 16.8% or more in the decision component of a complex dual-task. To examine whether the benefits of this technique are undermined in the presence of additional, unrelated sounds, a background recording of operations in a Navy command center and a voice communications response task [Bolia et al., J. Acoust. Soc. Am. 107, 1065-1066 (2000)] were used to simulate the conditions of an auditorily rich military environment. Without the benefit of spatialized sound cues, performance in the presence of this extraneous auditory information, as measured by decision response times, was an average of 13.6% worse than baseline performance in an earlier study. Performance improved when the cues were present by an average of 18.3%, but this improvement remained below the improvement observed in the baseline study by an average of 11.5%. It is concluded that while the two types of extraneous sound information used in this study degrade performance in the decision task, there is no interaction with the relative performance benefit provided by the use of spatialized auditory cues. [Work supported by ONR.

  19. New insights into non-precious metal catalyst layer designs for proton exchange membrane fuel cells: Improving performance and stability

    NASA Astrophysics Data System (ADS)

    Banham, Dustin; Kishimoto, Takeaki; Sato, Tetsutaro; Kobayashi, Yoshikazu; Narizuka, Kumi; Ozaki, Jun-ichi; Zhou, Yingjie; Marquez, Emil; Bai, Kyoung; Ye, Siyu

    2017-03-01

    The activity of non-precious metal catalysts (NPMCs) has now reached a stage at which they can be considered as possible alternatives to Pt for some proton exchange membrane fuel cell (PEMFC) applications. However, despite significant efforts over the past 50 years on catalyst development, only limited studies have been performed on NPMC-based cathode catalyst layer (CCL) designs. In this work, an extensive ionomer study is performed to investigate the impact of ionomer equivalent weight on performance, which has uncovered two crucial findings. Firstly, it is demonstrated that beyond a critical CCL conductance, no further improvement in performance is observed. The procedure used to determine this critical conductance can be used by other researchers in this field to aid in their design of high performing NPMC-based CCLs. Secondly, it is shown that the stability of NPMC-based CCLs can be improved through the use of low equivalent weight ionomers. This represents a completely unexplored pathway for further stability improvements, and also provides new insights into the possible degradation mechanisms occurring in NPMC-based CCLs. These findings have broad implications on all future NPMC-based CCL designs.

  20. Innovative and Successful Approaches to Improving Care Transitions From Hospital to Home

    PubMed Central

    Labson, Margherita C.

    2015-01-01

    Abstract Effective transitions to home care have been identified as among the factors leading to reducing hospital readmissions within 30 days of discharge and improvements on various other quality measures. Innovative applications of published evidence-based models and best practices designed to improve care transitions have been implemented in various settings across the country in an effort to enhance quality performance. For this article, The Joint Commission collected a series of case examples to examine how evidence-based innovations in care transitions are reducing readmissions and improving other quality outcomes. The organizations providing the case examples were interviewed and asked to provide performance data demonstrating quality improvement, as well as information about their care processes and data-gathering techniques. Their innovative approaches are reducing hospital readmissions; improving patient safety, satisfaction, and engagement; and contributing to other positive outcomes. PMID:25654457

  1. JT8D high pressure compressor performance improvement

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1981-01-01

    An improved performance high pressure compressor with potential application to all models of the JT8D engine was designed. The concept consisted of a trenched abradable rubstrip which mates with the blade tips for each of the even rotor stages. This feature allows tip clearances to be set so blade tips run at or near the optimum radius relative to the flowpath wall, without the danger of damaging the blades during transients and maneuvers. The improved compressor demonstrated thrust specific fuel consumption and exhaust gas temperature improvements of 1.0 percent and at least 10 C over the takeoff and climb power range at sea level static conditions, compared to a bill-of-material high pressure compressor. Surge margin also improved 4 percentage points over the high power operating range. A thrust specific fuel consumption improvement of 0.7 percent at typical cruise conditions was calculated based on the sea level test results.

  2. Antisolvent precipitation of novel xylitol-additive crystals to engineer tablets with improved pharmaceutical performance.

    PubMed

    Kaialy, Waseem; Maniruzzaman, Mohammad; Shojaee, Saeed; Nokhodchi, Ali

    2014-12-30

    The purpose of this work was to develop stable xylitol particles with modified physical properties, improved compactibility and enhanced pharmaceutical performance without altering polymorphic form of xylitol. Xylitol was crystallized using antisolvent crystallization technique in the presence of various hydrophilic polymer additives, i.e., polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) at a range of concentrations. The crystallization process did not influence the stable polymorphic form or true density of xylitol. However, botryoidal-shaped crystallized xylitols demonstrated different particle morphologies and lower powder bulk and tap densities in comparison to subangular-shaped commercial xylitol. Xylitol crystallized without additive and xylitol crystallized in the presence of PVP or PVA demonstrated significant improvement in hardness of directly compressed tablets; however, such improvement was observed to lesser extent for xylitol crystallized in the presence of PEG. Crystallized xylitols produced enhanced dissolution profiles for indomethacin in comparison to original xylitol. The influence of additive concentration on tablet hardness was dependent on the type of additive, whereas an increased concentration of all additives provided an improvement in the dissolution behavior of indomethacin. Antisolvent crystallization using judiciously selected type and concentration of additive can be a potential approach to prepare xylitol powders with promising physicomechanical and pharmaceutical properties. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Improving Teaching Capacity to Increase Student Achievement: The Key Role of Data Interpretation by School Leaders

    ERIC Educational Resources Information Center

    Lynch, David; Smith, Richard; Provost, Steven; Madden, Jake

    2016-01-01

    Purpose: This paper argues that in a well-organised school with strong leadership and vision coupled with a concerted effort to improve the teaching performance of each teacher, student achievement can be enhanced. The purpose of this paper is to demonstrate that while macro-effect sizes such as "whole of school" metrics are useful for…

  4. Impact resistance of hybrid composite fan blade materials

    NASA Technical Reports Server (NTRS)

    Friedrich, L. A.

    1974-01-01

    Improved resistance to foreign object damage was demonstrated for hybrid composite simulated blade specimens. Transply metallic reinforcement offered additional improvement in resistance to gelatin projectile impacts. Metallic leading edge protection permitted equivalent-to-titanium performance of the hybrid composite simulated blade specimen for impacts with 1.27 cm and 2.54 cm (0.50 and 1.00 inch) diameter gelatin spheres.

  5. Mutual information-based LPI optimisation for radar network

    NASA Astrophysics Data System (ADS)

    Shi, Chenguang; Zhou, Jianjiang; Wang, Fei; Chen, Jun

    2015-07-01

    Radar network can offer significant performance improvement for target detection and information extraction employing spatial diversity. For a fixed number of radars, the achievable mutual information (MI) for estimating the target parameters may extend beyond a predefined threshold with full power transmission. In this paper, an effective low probability of intercept (LPI) optimisation algorithm is presented to improve LPI performance for radar network. Based on radar network system model, we first provide Schleher intercept factor for radar network as an optimisation metric for LPI performance. Then, a novel LPI optimisation algorithm is presented, where for a predefined MI threshold, Schleher intercept factor for radar network is minimised by optimising the transmission power allocation among radars in the network such that the enhanced LPI performance for radar network can be achieved. The genetic algorithm based on nonlinear programming (GA-NP) is employed to solve the resulting nonconvex and nonlinear optimisation problem. Some simulations demonstrate that the proposed algorithm is valuable and effective to improve the LPI performance for radar network.

  6. Improved prescribed performance control for air-breathing hypersonic vehicles with unknown deadzone input nonlinearity.

    PubMed

    Wang, Yingyang; Hu, Jianbo

    2018-05-19

    An improved prescribed performance controller is proposed for the longitudinal model of an air-breathing hypersonic vehicle (AHV) subject to uncertain dynamics and input nonlinearity. Different from the traditional non-affine model requiring non-affine functions to be differentiable, this paper utilizes a semi-decomposed non-affine model with non-affine functions being locally semi-bounded and possibly in-differentiable. A new error transformation combined with novel prescribed performance functions is proposed to bypass complex deductions caused by conventional error constraint approaches and circumvent high frequency chattering in control inputs. On the basis of backstepping technique, the improved prescribed performance controller with low structural and computational complexity is designed. The methodology guarantees the altitude and velocity tracking error within transient and steady state performance envelopes and presents excellent robustness against uncertain dynamics and deadzone input nonlinearity. Simulation results demonstrate the efficacy of the proposed method. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  7. The Use of the Performance Diagnostic Checklist-Human Services to Assess and Improve the Job Performance of Individuals with Intellectual Disabilities.

    PubMed

    Smith, Madison; Wilder, David A

    2018-06-01

    The Performance Diagnostic Checklist-Human Services (PDC-HS) is an informant-based tool designed to identify the variables responsible for performance problems. To date, the PDC-HS has not been examined with individuals with intellectual disabilities. In the current study, two supervisors with intellectual disabilities completed the PDC-HS to assess the productivity of two supervisees with disabilities who performed a pricing task in a thrift store. The PDC-HS suggested that performance deficits were due to a lack of training; a PDC-HS-indicated intervention was effective to increase accurate pricing. • The PDC-HS is an informant-based tool designed to identify the variables responsible for employee performance problems in human service settings. • The PDC-HS can be completed by some individuals with intellectual disabilities in a supervisory position to identify the variables responsible for problematic job performance among their supervisees. • A PDC-HS indicated intervention was demonstrated to be effective to improve the job performance of individuals with disabilities. • The PDC-HS may be a useful tool to support performance improvement and job maintenance among individuals with intellectual disabilities.

  8. Enhanced change detection performance reveals improved strategy use in avid action video game players.

    PubMed

    Clark, Kait; Fleck, Mathias S; Mitroff, Stephen R

    2011-01-01

    Recent research has shown that avid action video game players (VGPs) outperform non-video game players (NVGPs) on a variety of attentional and perceptual tasks. However, it remains unknown exactly why and how such differences arise; while some prior research has demonstrated that VGPs' improvements stem from enhanced basic perceptual processes, other work indicates that they can stem from enhanced attentional control. The current experiment used a change-detection task to explore whether top-down strategies can contribute to VGPs' improved abilities. Participants viewed alternating presentations of an image and a modified version of the image and were tasked with detecting and localizing the changed element. Consistent with prior claims of enhanced perceptual abilities, VGPs were able to detect the changes while requiring less exposure to the change than NVGPs. Further analyses revealed this improved change detection performance may result from altered strategy use; VGPs employed broader search patterns when scanning scenes for potential changes. These results complement prior demonstrations of VGPs' enhanced bottom-up perceptual benefits by providing new evidence of VGPs' potentially enhanced top-down strategic benefits. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Performance evaluation capabilities for the design of physical systems

    NASA Technical Reports Server (NTRS)

    Pilkey, W. D.; Wang, B. P.

    1972-01-01

    The results are presented of a study aimed at developing and formulating a capability for the limiting performance of large steady state systems. The accomplishments reported include: (1) development of a theory of limiting performance of large systems subject to steady state inputs; (2) application and modification of PERFORM, the computational capability for the limiting performance of systems with transient inputs; and (3) demonstration that use of an inherently smooth control force for a limiting performance calculation improves the system identification phase of the design process for physical systems subjected to transient loading.

  10. Improving Seismic Data Accessibility and Performance Using HDF Containers

    NASA Astrophysics Data System (ADS)

    Evans, B. J. K.; Wang, J.; Yang, R.

    2017-12-01

    The performance of computational geophysical data processing and forward modelling relies on both computational and data. Significant efforts on developing new data formats and libraries have been made the community, such as IRIS/PASSCAL and ASDF in data, and programs and utilities such as ObsPy and SPECFEM. The National Computational Infrastructure hosts a national significant geophysical data collection that is co-located with a high performance computing facility and provides an opportunity to investigate how to improve the data formats from both a data management and a performance point of view. This paper investigates how to enhance the data usability in several perspectives: 1) propose a convention for the seismic (both active and passive) community to improve the data accessibility and interoperability; 2) recommend the convention used in the HDF container when data is made available in PH5 or ASDF formats; 3) provide tools to convert between various seismic data formats; 4) provide performance benchmark cases using ObsPy library and SPECFEM3D to demonstrate how different data organization in terms of chunking size and compression impact on the performance by comparing new data formats, such as PH5 and ASDF to traditional formats such as SEGY, SEED, SAC, etc. In this work we apply our knowledge and experience on data standards and conventions, such as CF and ACDD from the climate community to the seismology community. The generic global attributes widely used in climate community are combined with the existing convention in the seismology community, such as CMT and QuakeML, StationXML, SEGY header convention. We also extend such convention by including the provenance and benchmarking records so that the r user can learn the footprint of the data together with its baseline performance. In practise we convert the example wide angle reflection seismic data from SEGY to PH5 or ASDF by using ObsPy and pyasdf libraries. It quantitatively demonstrates how the accessibility can be improved if the seismic data are stored in the HDF container.

  11. Quality improvement project to reduce infiltration and extravasation events in a pediatric hospital.

    PubMed

    Tofani, Barbara F; Rineair, Sylvia A; Gosdin, Craig H; Pilcher, Patricia M; McGee, Susan; Varadarajan, Kartik R; Schoettker, Pamela J

    2012-12-01

    A safety event response team at Cincinnati Children's Hospital Medical Center developed and tested improvement strategies to reduce peripheral intravenous (PIV) infiltration and extravasation injuries. Improvement activities included development of the touch-look-compare method for hourly PIV site assessment, staff education and mandatory demonstration of PIV site assessment, and performance monitoring and sharing of compliance results. We observed a significant reduction in the injury rate immediately following implementation of the interventions that corresponded with monitoring compliance in performing hourly assessments on patients with a PIV, but this was not sustained. The team is currently examining other strategies to reduce PIV injuries. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Health Information Exchange Readiness for Demonstrating Return on Investment and Quality of Care.

    PubMed

    Khurshid, Anjum; Diana, Mark L; Jain, Rahul

    2015-01-01

    To study the extent to which community health information exchanges (HIEs) deliver and measure return on investment (ROI) and improvements in the quality of care. We surveyed operational HIEs for their characteristics, information domains, impact on quality of care, and ROI. A 60 percent response rate was achieved. Two-thirds of respondents agreed that community HIEs demonstrated a positive ROI, while one-third had no opinion or disagreed. One-fourth or fewer respondents reported using various metrics to calculate ROI. Most respondents agreed that HIEs improve the quality of care, though several were not sure and were awaiting further evidence. Most respondents indicated that they did not deliver reports on quality measures (76 percent) and that data were not being used to measure quality performance of participating providers (73 percent). Respondents from most HIEs believe that the HIEs are demonstrating a positive ROI; however, a minority of them indicated they had used or will use specific metrics to calculate ROI. HIE representatives overwhelmingly reported that they believe the HIE activities improve the quality of healthcare delivered, but only a few are using data to evaluate provider performance or generate reports on quality measures. This study demonstrates the challenge faced by policy makers and healthcare organizations that are investing millions of dollars in HIEs that are believed to improve health outcomes and increase efficiency, but still need more time to develop the evidence to confirm that belief. Our study shows that calculating ROI for HIEs or their impact on quality of care remains a secondary priority for most HIEs. This finding raises serious questions for the sustained support of HIEs, both financially and as a policy lever, given the end of Health Information Technology for Economic and Clinical Health (HITECH) Act funding.

  13. Improving the quality of primary care by allocating performance-based targets, in a diverse insured population.

    PubMed

    Peled, Ronit; Porath, Avi; Wilf-Miron, Rachel

    2016-11-21

    Primary Care Health organizations, operating under universal coverage and a regulated package of benefits, compete mainly over quality of care. Monitoring, primary care clinical performance, has been repeatedly proven effective in improving the quality of care. In 2004, Maccabi Healthcare Services (MHS), the second largest Israeli HMO, launched its Performance Measurement System (PMS) based on clinical quality indicators. A unique module was built in the PMS to adjust for case mix while tailoring targets to the local units. This article presents the concept and formulas developed to adjust targets to the units' current performance, and analyze change in clinical indicators over a six year period, between sub-population groups. Six process and intermediate outcome indicators, representing screening for breast and colorectal cancer and care for patients with diabetes and cardiovascular disease, were selected and analyzed for change over time (2003-2009) in overall performance, as well as the difference between the lowest and the highest socio-economic ranks (SERs) and Arab and non-Arab members. MHS demonstrated a significant improvement in the selected indicators over the years. Performance of members from low SERs and Arabs improved to a greater extent, as compared to members from high ranks and non-Arabs, respectively. The performance measurement system, with its module for tailoring of units' targets, served as a managerial vehicle for bridging existing gaps by allocating more resources to lower performing units. This concept was proven effective in improving performance while reducing disparities between diverse population groups.

  14. Early experience with pay-for-performance: from concept to practice.

    PubMed

    Rosenthal, Meredith B; Frank, Richard G; Li, Zhonghe; Epstein, Arnold M

    2005-10-12

    The adoption of pay-for-performance mechanisms for quality improvement is growing rapidly. Although there is intense interest in and optimism about pay-for-performance programs, there is little published research on pay-for-performance in health care. To evaluate the impact of a prototypical physician pay-for-performance program on quality of care. We evaluated a natural experiment with pay-for-performance using administrative reports of physician group quality from a large health plan for an intervention group (California physician groups) and a contemporaneous comparison group (Pacific Northwest physician groups). Quality improvement reports were included from October 2001 through April 2004 issued to approximately 300 large physician organizations. Three process measures of clinical quality: cervical cancer screening, mammography, and hemoglobin A1c testing. Improvements in clinical quality scores were as follows: for cervical cancer screening, 5.3% for California vs 1.7% for Pacific Northwest; for mammography, 1.9% vs 0.2%; and for hemoglobin A1c, 2.1% vs 2.1%. Compared with physician groups in the Pacific Northwest, the California network demonstrated greater quality improvement after the pay-for-performance intervention only in cervical cancer screening (a 3.6% difference in improvement [P = .02]). In total, the plan awarded 3.4 million dollars (27% of the amount set aside) in bonus payments between July 2003 and April 2004, the first year of the program. For all 3 measures, physician groups with baseline performance at or above the performance threshold for receipt of a bonus improved the least but garnered the largest share of the bonus payments. Paying clinicians to reach a common, fixed performance target may produce little gain in quality for the money spent and will largely reward those with higher performance at baseline.

  15. Fine tuning GPS clock estimation in the MCS

    NASA Technical Reports Server (NTRS)

    Hutsell, Steven T.

    1995-01-01

    With the completion of a 24 operational satellite constellation, GPS is fast approaching the critical milestone, Full Operational Capability (FOC). Although GPS is well capable of providing the timing accuracy and stability figures required by system specifications, the GPS community will continue to strive for further improvements in performance. The GPS Master Control Station (MCS) recently demonstrated that timing improvements are always composite Clock, and hence, Kalman Filter state estimation, providing a small improvement to user accuracy.

  16. A Modular Aerospike Engine Design Using Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Peugeot, John; Garcia, Chance; Burkhardt, Wendel

    2014-01-01

    A modular aerospike engine concept has been developed with the objective of demonstrating the viability of the aerospike design using additive manufacturing techniques. The aerospike system is a self-compensating design that allows for optimal performance over the entire flight regime and allows for the lowest possible mass vehicle designs. At low altitudes, improvements in Isp can be traded against chamber pressure, staging, and payload. In upper stage applications, expansion ratio and engine envelope can be traded against nozzle efficiency. These features provide flexibility to the System Designer optimizing a complete vehicle stage. The aerospike concept is a good example of a component that has demonstrated improved performance capability, but traditionally has manufacturing requirements that are too expensive and complex to use in a production vehicle. In recent years, additive manufacturing has emerged as a potential method for improving the speed and cost of building geometrically complex components in rocket engines. It offers a reduction in tooling overhead and significant improvements in the integration of the designer and manufacturing method. In addition, the modularity of the engine design provides the ability to perform full scale testing on the combustion devices outside of the full engine configuration. The proposed design uses a hydrocarbon based gas-generator cycle, with plans to take advantage of existing powerhead hardware while focusing DDT&E resources on manufacturing and sub-system testing of the combustion devices. The major risks for the modular aerospike concept lie in the performance of the propellant feed system, the structural integrity of the additive manufactured components, and the aerodynamic efficiency of the exhaust flow.

  17. Improving resolution of dynamic communities in human brain networks through targeted node removal

    PubMed Central

    Turner, Benjamin O.; Miller, Michael B.; Carlson, Jean M.

    2017-01-01

    Current approaches to dynamic community detection in complex networks can fail to identify multi-scale community structure, or to resolve key features of community dynamics. We propose a targeted node removal technique to improve the resolution of community detection. Using synthetic oscillator networks with well-defined “ground truth” communities, we quantify the community detection performance of a common modularity maximization algorithm. We show that the performance of the algorithm on communities of a given size deteriorates when these communities are embedded in multi-scale networks with communities of different sizes, compared to the performance in a single-scale network. We demonstrate that targeted node removal during community detection improves performance on multi-scale networks, particularly when removing the most functionally cohesive nodes. Applying this approach to network neuroscience, we compare dynamic functional brain networks derived from fMRI data taken during both repetitive single-task and varied multi-task experiments. After the removal of regions in visual cortex, the most coherent functional brain area during the tasks, community detection is better able to resolve known functional brain systems into communities. In addition, node removal enables the algorithm to distinguish clear differences in brain network dynamics between these experiments, revealing task-switching behavior that was not identified with the visual regions present in the network. These results indicate that targeted node removal can improve spatial and temporal resolution in community detection, and they demonstrate a promising approach for comparison of network dynamics between neuroscientific data sets with different resolution parameters. PMID:29261662

  18. Time domain topology optimization of 3D nanophotonic devices

    NASA Astrophysics Data System (ADS)

    Elesin, Y.; Lazarov, B. S.; Jensen, J. S.; Sigmund, O.

    2014-02-01

    We present an efficient parallel topology optimization framework for design of large scale 3D nanophotonic devices. The code shows excellent scalability and is demonstrated for optimization of broadband frequency splitter, waveguide intersection, photonic crystal-based waveguide and nanowire-based waveguide. The obtained results are compared to simplified 2D studies and we demonstrate that 3D topology optimization may lead to significant performance improvements.

  19. Zintl Phases for Thermoelectric Applications

    NASA Technical Reports Server (NTRS)

    Snyder, G. Jeffrey (Inventor); Toberer, Eric (Inventor); Zevalkink, Alex (Inventor)

    2014-01-01

    The inventors demonstrate herein that various Zintl compounds can be useful as thermoelectric materials for a variety of applications. Specifically, the utility of Ca3AlSb3, Ca5Al2Sb6, Ca5In2Sb6, Ca5Ga2Sb6, is described herein. Carrier concentration control via doping has also been demonstrated, resulting in considerably improved thermoelectric performance in the various systems described herein.

  20. A Project to Demonstrate Incremental Improvements in a K-12 Career Education Program through an Exemplary Model. Final Financial Status and Performance Report.

    ERIC Educational Resources Information Center

    Northwestern Tri-County Intermediate Unit 5, Edinboro, PA.

    A project was conducted based on the following three objectives: (1) demonstrate a regional plan for the implementation of an open entry-exit (flexible) career development program encompassing career awareness, career exploration, and career preparation; (2) expose each student to a range of career clusters within the context of his educational…

  1. High sensitivity optical measurement of skin gloss

    PubMed Central

    Ezerskaia, Anna; Ras, Arno; Bloemen, Pascal; Pereira, Silvania F.; Urbach, H. Paul; Varghese, Babu

    2017-01-01

    We demonstrate a low-cost optical method for measuring the gloss properties with improved sensitivity in the low gloss regime, relevant for skin gloss properties. The gloss estimation method is based on, on the one hand, the slope of the intensity gradient in the transition regime between specular and diffuse reflection and on the other on the sum over the intensities of pixels above threshold, derived from a camera image obtained using unpolarized white light illumination. We demonstrate the improved sensitivity of the two proposed methods using Monte Carlo simulations and experiments performed on ISO gloss calibration standards with an optical prototype. The performance and linearity of the method was compared with different professional gloss measurement devices based on the ratio of specular to diffuse intensity. We demonstrate the feasibility for in-vivo skin gloss measurements by quantifying the temporal evolution of skin gloss after application of standard paraffin cream bases on skin. The presented method opens new possibilities in the fields of cosmetology and dermatopharmacology for measuring the skin gloss and resorption kinetics and the pharmacodynamics of various external agents. PMID:29026683

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

    Farren Hunt

    Idaho National Laboratory (INL) performed an Annual Effectiveness Review of the Integrated Safety Management System (ISMS), per 48 Code of Federal Regulations (CFR) 970.5223 1, “Integration of Environment, Safety and Health into Work Planning and Execution.” The annual review assessed Integrated Safety Management (ISM) effectiveness, provided feedback to maintain system integrity, and identified target areas for focused improvements and assessments for fiscal year (FY) 2013. Results of the FY 2012 annual effectiveness review demonstrated that the INL’s ISMS program was significantly strengthened. Actions implemented by the INL demonstrate that the overall Integrated Safety Management System is sound and ensures safemore » and successful performance of work while protecting workers, the public, and environment. This report also provides several opportunities for improvement that will help further strengthen the ISM Program and the pursuit of safety excellence. Demonstrated leadership and commitment, continued surveillance, and dedicated resources have been instrumental in maturing a sound ISMS program. Based upon interviews with personnel, reviews of assurance activities, and analysis of ISMS process implementation, this effectiveness review concludes that ISM is institutionalized and is “Effective”.« less

  3. Web Transfer Over Satellites Being Improved

    NASA Technical Reports Server (NTRS)

    Allman, Mark

    1999-01-01

    Extensive research conducted by NASA Lewis Research Center's Satellite Networks and Architectures Branch and the Ohio University has demonstrated performance improvements in World Wide Web transfers over satellite-based networks. The use of a new version of the Hypertext Transfer Protocol (HTTP) reduced the time required to load web pages over a single Transmission Control Protocol (TCP) connection traversing a satellite channel. However, an older technique of simultaneously making multiple requests of a given server has been shown to provide even faster transfer time. Unfortunately, the use of multiple simultaneous requests has been shown to be harmful to the network in general. Therefore, we are developing new mechanisms for the HTTP protocol which may allow a single request at any given time to perform as well as, or better than, multiple simultaneous requests. In the course of study, we also demonstrated that the time for web pages to load is at least as short via a satellite link as it is via a standard 28.8-kbps dialup modem channel. This demonstrates that satellites are a viable means of accessing the Internet.

  4. High sensitivity optical measurement of skin gloss.

    PubMed

    Ezerskaia, Anna; Ras, Arno; Bloemen, Pascal; Pereira, Silvania F; Urbach, H Paul; Varghese, Babu

    2017-09-01

    We demonstrate a low-cost optical method for measuring the gloss properties with improved sensitivity in the low gloss regime, relevant for skin gloss properties. The gloss estimation method is based on, on the one hand, the slope of the intensity gradient in the transition regime between specular and diffuse reflection and on the other on the sum over the intensities of pixels above threshold, derived from a camera image obtained using unpolarized white light illumination. We demonstrate the improved sensitivity of the two proposed methods using Monte Carlo simulations and experiments performed on ISO gloss calibration standards with an optical prototype. The performance and linearity of the method was compared with different professional gloss measurement devices based on the ratio of specular to diffuse intensity. We demonstrate the feasibility for in-vivo skin gloss measurements by quantifying the temporal evolution of skin gloss after application of standard paraffin cream bases on skin. The presented method opens new possibilities in the fields of cosmetology and dermatopharmacology for measuring the skin gloss and resorption kinetics and the pharmacodynamics of various external agents.

  5. Improving Pediatric Rapid Response Team Performance Through Crew Resource Management Training of Team Leaders.

    PubMed

    Siems, Ashley; Cartron, Alexander; Watson, Anne; McCarter, Robert; Levin, Amanda

    2017-02-01

    Rapid response teams (RRTs) improve the detection of and response to deteriorating patients. Professional hierarchies and the multidisciplinary nature of RRTs hinder team performance. This study assessed whether an intervention involving crew resource management training of team leaders could improve team performance. In situ observations of RRT activations were performed pre- and post-training intervention. Team performance and dynamics were measured by observed adherence to an ideal task list and by the Team Emergency Assessment Measure tool, respectively. Multiple quartile (median) and logistic regression models were developed to evaluate change in performance scores or completion of specific tasks. Team leader and team introductions (40% to 90%, P = .004; 7% to 45%, P = .03), floor team presentations in Situation Background Assessment Recommendation format (20% to 65%, P = .01), and confirmation of the plan (7% to 70%, P = .002) improved after training in patients transferred to the ICU (n = 35). The Team Emergency Assessment Measure metric was improved in all 4 categories: leadership (2.5 to 3.5, P < .001), teamwork (2.7 to 3.7, P < .001), task management (2.9 to 3.8, P < .001), and global scores (6.0 to 9.0, P < .001) for teams caring for patients who required transfer to the ICU. Targeted crew resource management training of the team leader resulted in improved team performance and dynamics for patients requiring transfer to the ICU. The intervention demonstrated that training the team leader improved behavior in RRT members who were not trained. Copyright © 2017 by the American Academy of Pediatrics.

  6. Evaluation of safety and mobility of two-lane roundabouts : final report.

    DOT National Transportation Integrated Search

    2017-07-01

    When looking at measures of fatal and severe-injury crashes, roundabouts have demonstrated improved safety performance compared to traditional signalized intersections. Despite this, when it comes to less severe crashes, multilane roundabouts fail to...

  7. Parametric Bayesian priors and better choice of negative examples improve protein function prediction.

    PubMed

    Youngs, Noah; Penfold-Brown, Duncan; Drew, Kevin; Shasha, Dennis; Bonneau, Richard

    2013-05-01

    Computational biologists have demonstrated the utility of using machine learning methods to predict protein function from an integration of multiple genome-wide data types. Yet, even the best performing function prediction algorithms rely on heuristics for important components of the algorithm, such as choosing negative examples (proteins without a given function) or determining key parameters. The improper choice of negative examples, in particular, can hamper the accuracy of protein function prediction. We present a novel approach for choosing negative examples, using a parameterizable Bayesian prior computed from all observed annotation data, which also generates priors used during function prediction. We incorporate this new method into the GeneMANIA function prediction algorithm and demonstrate improved accuracy of our algorithm over current top-performing function prediction methods on the yeast and mouse proteomes across all metrics tested. Code and Data are available at: http://bonneaulab.bio.nyu.edu/funcprop.html

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

    Cheng, Fei; Gao, Jie; Luk, Ting S.

    Subwavelength structural color filtering and printing technologies employing plasmonic nanostructures have recently been recognized as an important and beneficial complement to the traditional colorant-based pigmentation. However, the color saturation, brightness and incident angle tolerance of structural color printing need to be improved to meet the application requirement. Here we demonstrate a structural color printing method based on plasmonic metasurfaces of perfect light absorption to improve color performances such as saturation and brightness. Thin-layer perfect absorbers with periodic hole arrays are designed at visible frequencies and the absorption peaks are tuned by simply adjusting the hole size and periodicity. Near perfectmore » light absorption with high quality factors are obtained to realize high-resolution, angle-insensitive plasmonic color printing with high color saturation and brightness. Moreover, the fabricated metasurfaces can be protected with a protective coating for ambient use without degrading performances. The demonstrated structural color printing platform offers great potential for applications ranging from security marking to information storage.« less

  9. [Nusing-sensitive indicadors: an opportunity for measuring the nurse contribution].

    PubMed

    Planas-Campmany, Carme; Icart-Isern, M Teresa

    2014-01-01

    The measures directed at improving the management and funding of health services that justify the measurement of performance and the purchase of services based on results, have a direct influence on nursing. In this context, concerns about the value and contribution of nursing have been demonstrated worldwide over the last decades. Therefore efforts are being made to ensure that nurses contribute to promote the transformation of health systems. This requires identifying their contribution to the health system and, specifically, in relation to health outcomes. In recent decades, there has been a growing demand to achieve measures which allow nurses to demonstrate and assume responsibility for their contribution. The research and development of nursing-sensitive indicators and results, and its application, provide an opportunity to measure the contribution and professional performance in achieving these set objectives, in order to improve population health. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  10. Nanoscale cryptography: opportunities and challenges.

    PubMed

    Masoumi, Massoud; Shi, Weidong; Xu, Lei

    2015-01-01

    While most of the electronics industry is dependent on the ever-decreasing size of lithographic transistors, this scaling cannot continue indefinitely. To improve the performance of the integrated circuits, new emerging and paradigms are needed. In recent years, nanoelectronics has become one of the most important and exciting forefront in science and engineering. It shows a great promise for providing us in the near future with many breakthroughs that change the direction of technological advances in a wide range of applications. In this paper, we discuss the contribution that nanotechnology may offer to the evolution of cryptographic hardware and embedded systems and demonstrate how nanoscale devices can be used for constructing security primitives. Using a custom set of design automation tools, it is demonstrated that relative to a conventional 45-nm CMOS system, performance gains can be obtained up to two orders of magnitude reduction in area and up to 50 % improvement in speed.

  11. Fast optically sectioned fluorescence HiLo endomicroscopy.

    PubMed

    Ford, Tim N; Lim, Daryl; Mertz, Jerome

    2012-02-01

    We describe a nonscanning, fiber bundle endomicroscope that performs optically sectioned fluorescence imaging with fast frame rates and real-time processing. Our sectioning technique is based on HiLo imaging, wherein two widefield images are acquired under uniform and structured illumination and numerically processed to reject out-of-focus background. This work is an improvement upon an earlier demonstration of widefield optical sectioning through a flexible fiber bundle. The improved device features lateral and axial resolutions of 2.6 and 17 μm, respectively, a net frame rate of 9.5 Hz obtained by real-time image processing with a graphics processing unit (GPU) and significantly reduced motion artifacts obtained by the use of a double-shutter camera. We demonstrate the performance of our system with optically sectioned images and videos of a fluorescently labeled chorioallantoic membrane (CAM) in the developing G. gallus embryo. HiLo endomicroscopy is a candidate technique for low-cost, high-speed clinical optical biopsies.

  12. Fast optically sectioned fluorescence HiLo endomicroscopy

    NASA Astrophysics Data System (ADS)

    Ford, Tim N.; Lim, Daryl; Mertz, Jerome

    2012-02-01

    We describe a nonscanning, fiber bundle endomicroscope that performs optically sectioned fluorescence imaging with fast frame rates and real-time processing. Our sectioning technique is based on HiLo imaging, wherein two widefield images are acquired under uniform and structured illumination and numerically processed to reject out-of-focus background. This work is an improvement upon an earlier demonstration of widefield optical sectioning through a flexible fiber bundle. The improved device features lateral and axial resolutions of 2.6 and 17 μm, respectively, a net frame rate of 9.5 Hz obtained by real-time image processing with a graphics processing unit (GPU) and significantly reduced motion artifacts obtained by the use of a double-shutter camera. We demonstrate the performance of our system with optically sectioned images and videos of a fluorescently labeled chorioallantoic membrane (CAM) in the developing G. gallus embryo. HiLo endomicroscopy is a candidate technique for low-cost, high-speed clinical optical biopsies.

  13. Improved FCG-1 cell technology

    NASA Astrophysics Data System (ADS)

    Breault, R. D.; Congdon, J. V.; Coykendall, R. D.; Luoma, W. L.

    1980-10-01

    Fuel cell performance in the ribbed substrate cell configuration consistent with that projected for a commercial power plant is demonstrated. Tests were conducted on subscale cells and on two 20 cell stacks of 4.8 MW demonstrator size cell components. These tests evaluated cell stack materials, processes, components, and assembly configurations. The first task was to conduct a component development effort to introduce improvements in 3.7 square foot, ribbed substrate acid cell repeating parts which represented advances in performance, function, life, and lower cost for application in higher pressure and temperature power plants. Specific areas of change were the electrode substrate, catalyst, matrix, seals, separator plates, and coolers. Full sized ribbed substrate stack components incorporating more stable materials were evaluated at increased pressure (93 psia) and temperature (405 F) conditions. Two 20 cell stacks with a 3.7 square feet, ribbed substrate cell configuration were tested.

  14. Pre-compensation combined with TS-aided and ISFA-enhanced scheme for UWB system

    NASA Astrophysics Data System (ADS)

    He, Jing; Xiang, Changqing; Long, Fengting; Wu, Kaiquan; Chen, Lin

    2017-08-01

    In this paper, a pre-compensation combined with training sequence (TS)-aided and intra-symbol frequency-domain averaging (ISFA)-enhanced scheme is proposed to improve the transmission performance in 64-quadrature amplitude modulation multiband orthogonal-frequency-division-multiplexing ultra-wide band over fiber (64QAM MB-OFDM UWBoF) system. We theoretically analyze and experimentally demonstrate that the proposed scheme is suitable for the 64QAM MB-OFDM UWBoF system in contrast with two other cases: (I) only pilot-aided channel estimation and (II) pilot-aided and pre-compensation combined with ISFA-enhanced channel estimation. The experimental results demonstrate that the performance of system with the proposed scheme can be improved by about 1.25 dB and 0.37 dB compared with the case I and the case II, respectively, at the BER of 3.8×10-3 after 70 km transmission in standard single mode fiber (SSMF).

  15. Chip-based quantum key distribution

    NASA Astrophysics Data System (ADS)

    Sibson, P.; Erven, C.; Godfrey, M.; Miki, S.; Yamashita, T.; Fujiwara, M.; Sasaki, M.; Terai, H.; Tanner, M. G.; Natarajan, C. M.; Hadfield, R. H.; O'Brien, J. L.; Thompson, M. G.

    2017-02-01

    Improvement in secure transmission of information is an urgent need for governments, corporations and individuals. Quantum key distribution (QKD) promises security based on the laws of physics and has rapidly grown from proof-of-concept to robust demonstrations and deployment of commercial systems. Despite these advances, QKD has not been widely adopted, and large-scale deployment will likely require chip-based devices for improved performance, miniaturization and enhanced functionality. Here we report low error rate, GHz clocked QKD operation of an indium phosphide transmitter chip and a silicon oxynitride receiver chip--monolithically integrated devices using components and manufacturing processes from the telecommunications industry. We use the reconfigurability of these devices to demonstrate three prominent QKD protocols--BB84, Coherent One Way and Differential Phase Shift--with performance comparable to state-of-the-art. These devices, when combined with integrated single photon detectors, pave the way for successfully integrating QKD into future telecommunications networks.

  16. Chip-based quantum key distribution

    PubMed Central

    Sibson, P.; Erven, C.; Godfrey, M.; Miki, S.; Yamashita, T.; Fujiwara, M.; Sasaki, M.; Terai, H.; Tanner, M. G.; Natarajan, C. M.; Hadfield, R. H.; O'Brien, J. L.; Thompson, M. G.

    2017-01-01

    Improvement in secure transmission of information is an urgent need for governments, corporations and individuals. Quantum key distribution (QKD) promises security based on the laws of physics and has rapidly grown from proof-of-concept to robust demonstrations and deployment of commercial systems. Despite these advances, QKD has not been widely adopted, and large-scale deployment will likely require chip-based devices for improved performance, miniaturization and enhanced functionality. Here we report low error rate, GHz clocked QKD operation of an indium phosphide transmitter chip and a silicon oxynitride receiver chip—monolithically integrated devices using components and manufacturing processes from the telecommunications industry. We use the reconfigurability of these devices to demonstrate three prominent QKD protocols—BB84, Coherent One Way and Differential Phase Shift—with performance comparable to state-of-the-art. These devices, when combined with integrated single photon detectors, pave the way for successfully integrating QKD into future telecommunications networks. PMID:28181489

  17. Furthering the quality agenda in Aboriginal community controlled health services: understanding the relationship between accreditation, continuous quality improvement and national key performance indicator reporting.

    PubMed

    Sibthorpe, Beverly; Gardner, Karen; McAullay, Daniel

    2016-01-01

    A rapidly expanding interest in quality in the Aboriginal-community-controlled health sector has led to widespread uptake of accreditation using more than one set of standards, a proliferation of continuous quality improvement programs and the introduction of key performance indicators. As yet, there has been no overarching logic that shows how they relate to each other, with consequent confusion within and outside the sector. We map the three approaches to the Framework for Performance Assessment in Primary Health Care, demonstrating their key differences and complementarity. There needs to be greater attention in both policy and practice to the purposes and alignment of the three approaches if they are to embed a system-wide focus that supports quality improvement at the service level.

  18. Reducing Plug Loads in Office Spaces: Hawaii and Guam Energy Improvement Technology Demonstration Project

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

    Sheppy, M.; Metzger, I.; Cutler, D.

    2014-01-01

    As part of its overall strategy to meet its energy goals, the Naval Facilities Engineering Command (NAVFAC) partnered with the Department of Energy's National Renewable Energy Laboratory (NREL) to rapidly demonstrate and deploy cost-effective renewable energy and energy efficiency technologies. This project was one of several demonstrations of new or underutilized commercial energy technologies. The common goal was to demonstrate and measure the performance and economic benefit of the system while monitoring any ancillary impacts to related standards of service and operation and maintenance (O&M) practices. In short, demonstrations at naval facilities simultaneously evaluate the benefits and compatibility of themore » technology with the U.S. Department of Defense (DOD) mission, and with NAVFAC's design, construction, operations, and maintenance practices, in particular. This project demonstrated the performance of commercially available advanced power strips (APSs) for plug load energy reductions in building A4 at Joint Base Pearl Harbor-Hickam (JBPHH), Hawaii.« less

  19. Interactive chemistry management system (ICMS); Field demonstration results at United Illuminating

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

    Noto, F.A.; Farrell, D.M.; Lombard, E.V.

    1988-01-01

    The authors report on a field demonstration of the interactive chemistry management system (ICMS) performed in the late summer of 1987 at the New Haven Harbor Station of United Illuminating Co. This demonstration was the first installation of the ICMS at an actual plant site. The ICMS is a computer-based system designed to monitor, diagnose, and provide optional automatic control of water and steam chemistry throughout the steam generator cycle. It is one of the diagnostic modules that comprises CE-TOPS (combustion engineering total on-line performance system), which continuously monitors operating conditions and suggests priority actions to increase operation efficiency, extendmore » the performance life of boiler components and reduce maintenance costs. By reducing the number of forced outages through early identification of potentially detrimental conditions, diagnosis of possible causes, and execution of corrective actions, improvements in unit availability and reliability will result.« less

  20. Design of a K/Q-Band Beacon Receiver for the Alphasat Technology Demonstration Payload (TDP) #5 Experiment

    NASA Technical Reports Server (NTRS)

    Morse, Jacquelynne R.

    2014-01-01

    This paper describes the design and performance of a coherent KQ-band (2040 GHz) beacon receiver developed at NASA Glenn Research Center (GRC) that will be installed at the Politecnico di Milano (POLIMI) for use in the Alphasat Technology Demonstration Payload 5 (TDP5) beacon experiment. The goal of this experiment is to characterize rain fade attenuation at 40 GHz to improve the performance of existing statistical rain attenuation models in the Q-band. The ground terminal developed by NASA GRC utilizes an FFT-based frequency estimation receiver capable of characterizing total path attenuation effects due to gaseous absorption, clouds, rain, and scintillation. The receiver system has been characterized in the lab and demonstrates a system dynamic range performance of better than 58 dB at 1 Hz and better than 48 dB at 10 Hz rates.

  1. Synthetic control of manganese birnessite: Impact of crystallite size on Li, Na, and Mg based electrochemistry

    DOE PAGES

    Yin, Jiefu; Takeuchi, Esther S.; Takeuchi, Kenneth J.; ...

    2016-08-12

    We demonstrated the synthesis and characterization of Mg-birnessite (Mg xMnO 2) with different crystallite sizes, prepared though low temperature precipitation and ion exchange. The influence of crystallite size on electrochemical performance of Mg-birnessite was studied for the first time, where material with smaller crystallite size was demonstrated to have enhanced capacity and rate capability in Li ion, Na ion, and Mg ion based electrolytes. Cation diffusion using GITT type testing demonstrated the ion diffusion coefficient of Mg 2+ was ~10× lower compared with Li + and Na +. This work illustrates that tuning of inorganic materials properties can lead tomore » significant enhancement of electrochemical performance in lithium, sodium as well as magnesium based batteries for materials such as Mg-birnessite and provides a deliberate approach to improve electrochemical performance.« less

  2. The Efficacy of an 8-Week Concurrent Strength and Endurance Training Programme on Hand Cycling Performance.

    PubMed

    Nevin, Jonpaul; Waldron, Mark; Patterson, Stephen; Smith, Paul; Price, Mike; Hunt, Alex

    2018-03-20

    The aim of the present study was to investigate the effects of an 8-week concurrent strength and endurance training programme in comparison to endurance training only on several key determinants of hand cycling performance. Five H4 and five H3 classified hand cyclists with at least one year's hand cycling training history consented to participate in the study. Subjects underwent a battery of tests to establish body mass, body composition, VO2peak, maximum aerobic power, gross mechanical efficiency, maximal upper body strength, and 30 km time trial performance. Subjects were matched into pairs based upon 30 km time trial performance and randomly allocated to either a concurrent strength and endurance or endurance training only, intervention group. Following an 8-week training programme based upon a conjugated block periodisation model, subjects completed a second battery of tests. A mixed model, 2-way analysis of variance (ANOVA) revealed no significant changes between groups. However, the calculation of effect sizes (ES) revealed that both groups demonstrated a positive improvement in most physiological and performance measures with subjects in the concurrent group demonstrating a greater magnitude of improvement in body composition (ES -0.80 vs. -0.22) maximal aerobic power (ES 0.97 vs. 0.28), gross mechanical efficiency (ES 0.87 vs. 0.63), bench press 1 repetition maximum (ES 0.53 vs. 0.33), seated row 1 repetition maximum (ES 1.42 vs. 0.43), and 30 km time trial performance (ES -0.66 vs. -0.30). In comparison to endurance training only, an 8-week concurrent training intervention based upon a conjugated block periodisation model appears to be a more effective training regime for improving the performance capabilities of hand cyclists.

  3. A Hybrid Approach to Detect Driver Drowsiness Utilizing Physiological Signals to Improve System Performance and Wearability.

    PubMed

    Awais, Muhammad; Badruddin, Nasreen; Drieberg, Micheal

    2017-08-31

    Driver drowsiness is a major cause of fatal accidents, injury, and property damage, and has become an area of substantial research attention in recent years. The present study proposes a method to detect drowsiness in drivers which integrates features of electrocardiography (ECG) and electroencephalography (EEG) to improve detection performance. The study measures differences between the alert and drowsy states from physiological data collected from 22 healthy subjects in a driving simulator-based study. A monotonous driving environment is used to induce drowsiness in the participants. Various time and frequency domain feature were extracted from EEG including time domain statistical descriptors, complexity measures and power spectral measures. Features extracted from the ECG signal included heart rate (HR) and heart rate variability (HRV), including low frequency (LF), high frequency (HF) and LF/HF ratio. Furthermore, subjective sleepiness scale is also assessed to study its relationship with drowsiness. We used paired t -tests to select only statistically significant features ( p < 0.05), that can differentiate between the alert and drowsy states effectively. Significant features of both modalities (EEG and ECG) are then combined to investigate the improvement in performance using support vector machine (SVM) classifier. The other main contribution of this paper is the study on channel reduction and its impact to the performance of detection. The proposed method demonstrated that combining EEG and ECG has improved the system's performance in discriminating between alert and drowsy states, instead of using them alone. Our channel reduction analysis revealed that an acceptable level of accuracy (80%) could be achieved by combining just two electrodes (one EEG and one ECG), indicating the feasibility of a system with improved wearability compared with existing systems involving many electrodes. Overall, our results demonstrate that the proposed method can be a viable solution for a practical driver drowsiness system that is both accurate and comfortable to wear.

  4. A Hybrid Approach to Detect Driver Drowsiness Utilizing Physiological Signals to Improve System Performance and Wearability

    PubMed Central

    Badruddin, Nasreen

    2017-01-01

    Driver drowsiness is a major cause of fatal accidents, injury, and property damage, and has become an area of substantial research attention in recent years. The present study proposes a method to detect drowsiness in drivers which integrates features of electrocardiography (ECG) and electroencephalography (EEG) to improve detection performance. The study measures differences between the alert and drowsy states from physiological data collected from 22 healthy subjects in a driving simulator-based study. A monotonous driving environment is used to induce drowsiness in the participants. Various time and frequency domain feature were extracted from EEG including time domain statistical descriptors, complexity measures and power spectral measures. Features extracted from the ECG signal included heart rate (HR) and heart rate variability (HRV), including low frequency (LF), high frequency (HF) and LF/HF ratio. Furthermore, subjective sleepiness scale is also assessed to study its relationship with drowsiness. We used paired t-tests to select only statistically significant features (p < 0.05), that can differentiate between the alert and drowsy states effectively. Significant features of both modalities (EEG and ECG) are then combined to investigate the improvement in performance using support vector machine (SVM) classifier. The other main contribution of this paper is the study on channel reduction and its impact to the performance of detection. The proposed method demonstrated that combining EEG and ECG has improved the system’s performance in discriminating between alert and drowsy states, instead of using them alone. Our channel reduction analysis revealed that an acceptable level of accuracy (80%) could be achieved by combining just two electrodes (one EEG and one ECG), indicating the feasibility of a system with improved wearability compared with existing systems involving many electrodes. Overall, our results demonstrate that the proposed method can be a viable solution for a practical driver drowsiness system that is both accurate and comfortable to wear. PMID:28858220

  5. Objective Structured Assessment of Technical Skills (OSATS) evaluation of hysteroscopy training: a prospective study.

    PubMed

    Alici, Ferizan; Buerkle, Bernd; Tempfer, Clemens B

    2014-07-01

    To describe the performance curve of hysteroscopy-naïve probands repeatedly working through a surgery algorithm on a hysteroscopy trainer. We prospectively recruited medical students to a 30min demonstration session teaching a standardized surgery algorithm. Subjects subsequently performed three training courses immediately after training (T1) and after 24h (T2) and 48h (T3). Skills were recorded with a 20-item Objective Structured Assessment of Technical Skills (OSATS) at T1, T2, and T3. The presence of a sustained OSATS score improvement from T1 to T3 was the primary outcome. Performance time (PT) and self assessment (SA) were secondary outcomes. Statistics were performed using paired T-test and multiple linear regression analysis. 92 subjects were included. OSATS scores significantly improved over time from T1 to T2 (15.21±1.95 vs. 16.02±2.06, respectively; p<0.0001) and from T2 to T3 (16.02±2.06 vs. 16.95±1.61, respectively; p<0.0001). The secondary outcomes PT (414±119s vs. 357±88s vs. 304±91s; p<0.0001) and SA (3.02±0.85 vs. 3.80±0.76 vs. 4.41±0.67; p<0.0001) also showed an improvement over time with quicker performance and higher confidence. SA, but not PT demonstrated construct validity. In a multiple linear regression analysis, gender (odds ratio (OR) 0.96; 95% confidence interval (CI) 0.35-2.71; p=0.9) did not independently influence the likelihood of OSATS score improvement. In a hysteroscopy-naïve population, there is a continuous and sustained improvement of surgical proficiency and confidence after multiple training courses on a hysteroscopy trainer. Serial hysteroscopy trainings may be helpful for teaching hysteroscopy skills. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Does Winning a Pay-for-Performance Bonus Improve Subsequent Quality Performance? Evidence from the Hospital Quality Incentive Demonstration

    PubMed Central

    Ryan, Andrew; Sutton, Matthew; Doran, Tim

    2014-01-01

    Objective To test whether receiving a financial bonus for quality in the Premier Hospital Quality Incentive Demonstration (HQID) stimulated subsequent quality improvement. Data Hospital-level data on process-of-care quality from Hospital Compare for the treatment of acute myocardial infarction (AMI), heart failure, and pneumonia for 260 hospitals participating in the HQID from 2004 to 2006; receipt of quality bonuses in the first 3 years of HQID from the Premier Inc. website; and hospital characteristics from the 2005 American Hospital Association Annual Survey. Study Design Under the HQID, hospitals received a 1 percent bonus on Medicare payments for scoring between the 80th and 90th percentiles on a composite quality measure, and a 2 percent bonus for scoring at the 90th percentile or above. We used a regression discontinuity design to evaluate whether hospitals with quality scores just above these payment thresholds improved more in the subsequent year than hospitals with quality scores just below the thresholds. In alternative specifications, we examined samples of hospitals scoring within 3, 5, and 10 percentage point “bandwidths” of the thresholds. We used a Generalized Linear Model to estimate whether the relationship between quality and lagged quality was discontinuous at the lagged thresholds required for quality bonuses. Principal Findings There were no statistically significant associations between receipt of a bonus and subsequent quality performance, with the exception of the 2 percent bonus for AMI in 2006 using the 5 percentage point bandwidth (0.8 percentage point increase, p < .01), and the 1 percent bonus for pneumonia in 2005 using all bandwidths (3.7 percentage point increase using the 3 percentage point bandwidth, p < .05). Conclusions We found little evidence that hospitals' receipt of quality bonuses was associated with subsequent improvement in performance. This raises questions about whether winning in pay-for-performance programs, such as Hospital Value-Based Purchasing, will lead to subsequent quality improvement. PMID:23909992

  7. Group changes in cognitive performance after surgery mask changes in individual patients with Glioblastoma.

    PubMed

    van Loenen, Inge S; Rijnen, Sophie Jm; Bruijn, Jimme; Rutten, Geert-Jan M; Gehring, Karin; Sitskoorn, Margriet M

    2018-06-07

    There is a growing interest to include evaluations of cognitive performance in the clinical management of patients with Glioblastoma (GBM). However, as changes in cognitive performance of a group may mask changes in individual patients, study results are often difficult to transfer into clinical practice. We focused on the comparison of group versus individual changes in neuropsychological performance of GBM patients after initial surgical treatment. Patients underwent neuropsychological evaluation using CNS Vital Signs one day prior to, and three months after surgery. Two-tailed paired samples t-tests were conducted to assess changes on the group level. Reliable Change Indices (RCIs), that correct for practice effects and imperfect test-retest reliabilities, were used to examine change in individual patients. Cognitive dysfunction was common (>80%) both before and three months after surgery in this sample of 82 GBM patients. Whereas group analyses revealed minimal changes in performance over time, RCIs demonstrated that most patients (89%) showed changes in performance in at least one cognitive domain. Half of these individual patients solely showed improvements, a quarter solely showed declines, and another quarter showed both improvements and declines. This study clearly demonstrates that important individual changes in performance are masked when looking only at group results. Future studies should more often use an individual patient approach to enhance knowledge transfer into clinical practice. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  8. Parallel k-means++ for Multiple Shared-Memory Architectures

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

    Mackey, Patrick S.; Lewis, Robert R.

    2016-09-22

    In recent years k-means++ has become a popular initialization technique for improved k-means clustering. To date, most of the work done to improve its performance has involved parallelizing algorithms that are only approximations of k-means++. In this paper we present a parallelization of the exact k-means++ algorithm, with a proof of its correctness. We develop implementations for three distinct shared-memory architectures: multicore CPU, high performance GPU, and the massively multithreaded Cray XMT platform. We demonstrate the scalability of the algorithm on each platform. In addition we present a visual approach for showing which platform performed k-means++ the fastest for varyingmore » data sizes.« less

  9. [Lung Abscess with Acute Empyema Which Improved after Performing by Video Assissted Thoracic Surgery( Including Pneumonotomy and Lung Abscess Drainage);Report of a Case].

    PubMed

    Gabe, Atsushi; Nagamine, Naoji

    2017-05-01

    We herein report the case of a patient demonstrating a lung abscess with acute empyema which improved after performing pnemumonotomy and lung abscess drainage. A 60-year-old male was referred to our hospital to receive treatment for a lung abscess with acute empyema. At surgery, the lung parenchyma was slightly torn with pus leakage. After drainage of lung abscess by enlarging the injured part, curettage in the thoracic cavity and decortication were performed. The postoperative course was uneventful. Direct drainage of an abscess into the thoracic cavity is thought to be a choice for the treatment of lung abscesses.

  10. Do repeated assessments of performance status improve predictions for risk of death among patients with cancer? A population-based cohort study.

    PubMed

    Su, Jiandong; Barbera, Lisa; Sutradhar, Rinku

    2015-06-01

    Prior work has utilized longitudinal information on performance status to demonstrate its association with risk of death among cancer patients; however, no study has assessed whether such longitudinal information improves the predictions for risk of death. To examine whether the use of repeated performance status assessments improve predictions for risk of death compared to using only performance status assessment at the time of cancer diagnosis. This was a population-based longitudinal study of adult outpatients who had a cancer diagnosis and had at least one assessment of performance status. To account for each patient's changing performance status over time, we implemented a Cox model with a time-varying covariate for performance status. This model was compared to a Cox model using only a time-fixed (baseline) covariate for performance status. The regression coefficients of each model were derived based on a randomly selected 60% of patients, and then, the predictive ability of each model was assessed via concordance probabilities when applied to the remaining 40% of patients. Our study consisted of 15,487 cancer patients with over 53,000 performance status assessments. The utilization of repeated performance status assessments improved predictions for risk of death compared to using only the performance status assessment taken at diagnosis. When studying the hazard of death among patients with cancer, if available, researchers should incorporate changing information on performance status scores, instead of simply baseline information on performance status. © The Author(s) 2015.

  11. Extrapyramidal signs in normal pressure hydrocephalus: an objective assessment

    PubMed Central

    Mandir, Allen S; Hilfiker, Jennifer; Thomas, George; Minahan, Robert E; Crawford, Thomas O; Williams, Michael A; Rigamonti, Daniele

    2007-01-01

    Background Beyond the classic Normal Pressure Hydrocephalus (NPH) triad of gait disturbance, incontinence, and dementia are characteristic signs of motor dysfunction in NPH patients. We used highly sensitive and objective methods to characterize upper limb extrapyramidal signs in a series of NPH subjects compared with controls. Concentrated evaluation of these profound, yet underappreciated movement disorders of NPH before and after techniques of therapeutic intervention may lead to improved diagnosis, insight into pathophysiology, and targeted treatment. Methods Twenty-two (22) consecutive NPH patients and 17 controls performed an upper limb motor task battery where highly sensitive and objective measures of akinesia/bradykinesia, tone, and tremor were conducted. NPH subjects performed this test battery before and more than 36 h after continuous CSF drainage via a spinal catheter over 72 h and, in those subjects undergoing permanent ventriculo-peritoneal shunt placement, at least 12 weeks later. Control subjects performed the task battery at the same dates as the NPH subjects. Statistical analyses were applied to group populations of NPH and control subjects and repeated measures for within subject performance. Results Twenty (20) NPH subjects remained in the study following CSF drainage as did 14 controls. NPH subjects demonstrated akinesia/bradykinesia (prolonged reaction and movement times) and increased resting tone compared with controls. Furthermore, the NPH group demonstrated increased difficulty with self-initiated tasks compared with stimulus-initiated tasks. Following CSF drainage, some NPH subjects demonstrated reduced movement times with greater improvement in self- versus stimulus-initiated tasks. Group reaction time was unchanged. Resting tremor present in one NPH subject resolved following shunt placement. Tone measures were consistent for all subjects throughout the study. Conclusion Clinical motor signs of NPH subjects extend beyond gait deficits and include extrapyramidal manifestations of bradykinesia, akinesia, rigidity, and propensity to perform more poorly when external cues to move are absent. Objective improvement of some but not all of these features was seen following temporary or permanent CSF diversion. PMID:17697324

  12. Advanced Small Rocket Chambers. Option 3: 110 1Bf Ir-Re Rocket, Volume 1

    NASA Technical Reports Server (NTRS)

    Jassowski, Donald M.; Schoenman, Leonard

    1995-01-01

    This report describes the AJ10-221, a high performance Iridium-coated Rhenium (Ir-Re) 110 lbf (490N) welded rocket chamber with 286:1 area ratio nozzle. This engine was designed, built, and hot fired for over 6 hours on this program. It demonstrated an I(s) of 321.8 sec, which is 10 sec higher than conventional 110 lbf silicide coated Cb chambers now in use. The approach used in this portion of the program was to demonstrate the performance improvement that can be made by the elimination of fuel film cooling and the use of a high temperature (4000F) (2200C) iridium-coated rhenium (Ir-Re) rocket chamber. Detailed thermal, performance, mechanical, and dynamic design analyses of the full engine were conducted by Aerojet. Two Ir-Re chambers were built to the Aerojet design by Ultramet, using the chemical vapor deposition (CVD) process. Incorporation of a secondary mixing device or Boundary Layer Trip (BLT) within the combustion chamber (Aerojet Patents 4882904 and 4936091) results in improvement in flow uniformity, and a significant life and performance increase. The 110 lbf engine design was verified in bolt-up hardware tests at sea level and altitude. The effects of injector design on performance were studied. Two duplicate injectors were fabricated matching the preferred design and were demonstrated to be interchangeable in operation. One of these units was fabricated matching the preferred design and was demonstrated to be interchangeable in operation. One of these units was welded into a flight type thruster which was tested for an accumulated duration of 22,590 sec in 93 firings, one of which was a continuous burn of two hours. A design deficiency in the C-103 nozzle near the Re-Cb transition joint was discovered, studied and corrected design has been prepared. Workhardening studies have been conducted to investigate methods for increasing the low yield strength of the Re in the annealed conditions. An advanced 490N high performance engine has been demonstrated which, when proven to be capable of withstanding launch vibration, is ready for flight qualification.

  13. On the use of controls for subsonic transport performance improvement: Overview and future directions

    NASA Technical Reports Server (NTRS)

    Gilyard, Glenn; Espana, Martin

    1994-01-01

    Increasing competition among airline manufacturers and operators has highlighted the issue of aircraft efficiency. Fewer aircraft orders have led to an all-out efficiency improvement effort among the manufacturers to maintain if not increase their share of the shrinking number of aircraft sales. Aircraft efficiency is important in airline profitability and is key if fuel prices increase from their current low. In a continuing effort to improve aircraft efficiency and develop an optimal performance technology base, NASA Dryden Flight Research Center developed and flight tested an adaptive performance seeking control system to optimize the quasi-steady-state performance of the F-15 aircraft. The demonstrated technology is equally applicable to transport aircraft although with less improvement. NASA Dryden, in transitioning this technology to transport aircraft, is specifically exploring the feasibility of applying adaptive optimal control techniques to performance optimization of redundant control effectors. A simulation evaluation of a preliminary control law optimizes wing-aileron camber for minimum net aircraft drag. Two submodes are evaluated: one to minimize fuel and the other to maximize velocity. This paper covers the status of performance optimization of the current fleet of subsonic transports. Available integrated controls technologies are reviewed to define approaches using active controls. A candidate control law for adaptive performance optimization is presented along with examples of algorithm operation.

  14. Highly Conductive Solid-State Hybrid Electrolytes Operating at Subzero Temperatures.

    PubMed

    Kwon, Taeyoung; Choi, Ilyoung; Park, Moon Jeong

    2017-07-19

    We report a unique, highly conductive, dendrite-inhibited, solid-state polymer electrolyte platform that demonstrates excellent battery performance at subzero temperatures. A design based on functionalized inorganic nanoparticles with interconnected mesopores that contain surface nitrile groups is the key to this development. Solid-state hybrid polymer electrolytes based on succinonitrile (SN) electrolytes and porous nanoparticles were fabricated via a simple UV-curing process. SN electrolytes were effectively confined within the mesopores. This stimulated favorable interactions with lithium ions, reduced leakage of SN electrolytes over time, and improved mechanical strength of membranes. Inhibition of lithium dendrite growth and improved electrochemical stability up to 5.2 V were also demonstrated. The hybrid electrolytes exhibited high ionic conductivities of 2 × 10 -3 S cm -1 at room temperature and >10 -4 S cm -1 at subzero temperatures, leading to stable and improved battery performance at subzero temperatures. Li cells made with lithium titanate anodes exhibited stable discharge capacities of 151 mAh g -1 at temperatures below -10 °C. This corresponds to 92% of the capacity achieved at room temperature (164 mAh g -1 ). Our work represents a significant advance in solid-state polymer electrolyte technology and far exceeds the performance available with conventional polymeric battery separators.

  15. Aerobic conditioning for team sport athletes.

    PubMed

    Stone, Nicholas M; Kilding, Andrew E

    2009-01-01

    Team sport athletes require a high level of aerobic fitness in order to generate and maintain power output during repeated high-intensity efforts and to recover. Research to date suggests that these components can be increased by regularly performing aerobic conditioning. Traditional aerobic conditioning, with minimal changes of direction and no skill component, has been demonstrated to effectively increase aerobic function within a 4- to 10-week period in team sport players. More importantly, traditional aerobic conditioning methods have been shown to increase team sport performance substantially. Many team sports require the upkeep of both aerobic fitness and sport-specific skills during a lengthy competitive season. Classic team sport trainings have been shown to evoke marginal increases/decreases in aerobic fitness. In recent years, aerobic conditioning methods have been designed to allow adequate intensities to be achieved to induce improvements in aerobic fitness whilst incorporating movement-specific and skill-specific tasks, e.g. small-sided games and dribbling circuits. Such 'sport-specific' conditioning methods have been demonstrated to promote increases in aerobic fitness, though careful consideration of player skill levels, current fitness, player numbers, field dimensions, game rules and availability of player encouragement is required. Whilst different conditioning methods appear equivalent in their ability to improve fitness, whether sport-specific conditioning is superior to other methods at improving actual game performance statistics requires further research.

  16. A systematic review of the efficacy of ergogenic aids for improving running performance.

    PubMed

    Schubert, Matthew M; Astorino, Todd A

    2013-06-01

    Running is a common form of activity worldwide, and participants range from "weekend warriors" to Olympians. Unfortunately, few studies have examined efficacy of various ergogenic aids in runners because the majority of the literature consists of cycling-based protocols, which do not relate to running performance. The majority of running studies conducted markedly vary in regards to specific distance completed, subject fitness level, and effectiveness of the ergogenic aid examined. The aim of this article was to systematically examine the literature concerning utility of several ergogenic aids on middle-distance running (400-5,000 m) and long-distance running (10,000 meters marathon = 42.2 km) performance. In addition, this article highlights the dearth of running-specific studies in the literature and addresses recommendations for future research to optimize running performance through nutritional intervention. Results revealed 23 studies examining effects of various ergogenic aids on running performance, with a mean Physiotherapy Evidence Database score equal to 7.85 ± 0.70. Of these studies, 71% (n = 15) demonstrated improved running performance with ergogenic aid ingestion when compared with a placebo trial. The most effective ergogenic aids for distances from 400 m to 40 km included sodium bicarbonate (4 studies; 1.5 ± 1.1% improvement), sodium citrate (6 studies; 0.3 ± 1.7% improvement), caffeine (CAFF) (7 studies; 1.1 ± 0.4% improvement), and carbohydrate (CHO) (6 studies; 4.1 ± 4.4% improvement). Therefore, runners may benefit from ingestion of sodium bicarbonate to enhance middle distance performance and caffeine and carbohydrate to enhance performance at multiple distances.

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

    Farrar, Sara; Rothgeb, Stacey; Polly, Ben

    The U.S. Department of Energy (DOE) Building America Program enables the transformation of the U.S. housing industry to achieve energy savings through energy-efficient, high-performance homes with improved durability, comfort, and health for occupants. Building America bridges the gap between the development of emerging technologies and the adoption of codes and standards by engaging industry partners in applied research, development, and demonstration of high-performance solutions.

  18. Healthy School Environment and Enhanced Educational Performance: The Case of Charles Young Elementary School, Washington, DC.

    ERIC Educational Resources Information Center

    Berry, Michael A.

    This report presents a case study of the renovation of Charles Young Elementary School in Washington, DC, focusing on how an improved school environment contributed to higher levels of educational performance. The school was chosen as a school revitalization demonstration project for the Urban Schools Initiative. The objective of the project was…

  19. Lithium-Ion Batteries for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Surampudi, S.; Halpert, G.; Marsh, R. A.; James, R.

    1999-01-01

    This presentation reviews: (1) the goals and objectives, (2) the NASA and Airforce requirements, (3) the potential near term missions, (4) management approach, (5) the technical approach and (6) the program road map. The objectives of the program include: (1) develop high specific energy and long life lithium ion cells and smart batteries for aerospace and defense applications, (2) establish domestic production sources, and to demonstrate technological readiness for various missions. The management approach is to encourage the teaming of universities, R&D organizations, and battery manufacturing companies, to build on existing commercial and government technology, and to develop two sources for manufacturing cells and batteries. The technological approach includes: (1) develop advanced electrode materials and electrolytes to achieve improved low temperature performance and long cycle life, (2) optimize cell design to improve specific energy, cycle life and safety, (3) establish manufacturing processes to ensure predictable performance, (4) establish manufacturing processes to ensure predictable performance, (5) develop aerospace lithium ion cells in various AH sizes and voltages, (6) develop electronics for smart battery management, (7) develop a performance database required for various applications, and (8) demonstrate technology readiness for the various missions. Charts which review the requirements for the Li-ion battery development program are presented.

  20. DoE Phase II SBIR: Spectrally-Assisted Vehicle Tracking

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

    Villeneuve, Pierre V.

    2013-02-28

    The goal of this Phase II SBIR is to develop a prototype software package to demonstrate spectrally-aided vehicle tracking performance. The primary application is to demonstrate improved target vehicle tracking performance in complex environments where traditional spatial tracker systems may show reduced performance. Example scenarios in Figure 1 include a) the target vehicle obscured by a large structure for an extended period of time, or b), the target engaging in extreme maneuvers amongst other civilian vehicles. The target information derived from spatial processing is unable to differentiate between the green versus the red vehicle. Spectral signature exploitation enables comparison ofmore » new candidate targets with existing track signatures. The ambiguity in this confusing scenario is resolved by folding spectral analysis results into each target nomination and association processes. Figure 3 shows a number of example spectral signatures from a variety of natural and man-made materials. The work performed over the two-year effort was divided into three general areas: algorithm refinement, software prototype development, and prototype performance demonstration. The tasks performed under this Phase II to accomplish the program goals were as follows: 1. Acquire relevant vehicle target datasets to support prototype. 2. Refine algorithms for target spectral feature exploitation. 3. Implement a prototype multi-hypothesis target tracking software package. 4. Demonstrate and quantify tracking performance using relevant data.« less

  1. Pitting and Bending Fatigue Evaluations of a New Case-Carburized Gear Steel

    NASA Technical Reports Server (NTRS)

    Krantz, Timothy; Tufts, Brian

    2007-01-01

    The power density of a gearbox is an important consideration for many applications and is especially important for gearboxes used on aircraft. One approach to improving power density of gearing is to improve the steel properties by design of the alloy. The alloy tested in this work was designed to be case-carburized with surface hardness of Rockwell C66 after hardening. Test gear performance was evaluated using surface fatigue tests and single-tooth bending fatigue tests. The performance of gears made from the new alloy was compared to the performance of gears made from two alloys currently used for aviation gearing. The new alloy exhibited significantly better performance in surface fatigue testing, demonstrating the value of the improved properties in the case layer. However, the alloy exhibited lesser performance in single-tooth bending fatigue testing. The fracture toughness of the tested gears was insufficient for use in aircraft applications as judged by the behavior exhibited during the single tooth bending tests. This study quantified the performance of the new alloy and has provided guidance for the design and development of next generation gear steels.

  2. Evaluating mepindolol in a test model of examination anxiety in students.

    PubMed

    Krope, P; Kohrs, A; Ott, H; Wagner, W; Fichte, K

    1982-03-01

    The effect of a single dose of beta-blocker (5 or 10 mg mepindolol) during a written examination was investigated in two double-blind studies (N : 49 and 55 students, respectively). The question was whether the beta-blocker would in comparison to placebo diminish examination anxiety and improve the performance of highly complex tasks, while leaving the performance of less complex tasks unchanged. A reduction in examination anxiety after beta-blocker intake could not be demonstrated with a multi-level test model (which included the parameters self-rated anxiety, motor behaviour, task performance and physiology), although pulse rates were lowered significantly. An improvement in performance could not be observed, while - by the same token - the performance was not impaired by the beta-blocker. A hypothesis according to which a beta-blocker has an anxiolytic effect and improves performance, dependent on the level of habitual examination anxiety, was tested post hoc, but could not be confirmed. Ten of the subjects treated with 10 mg mepindolol, complained of different side effects, including dizziness, fatigue and headache.

  3. Semiconducting carbon nanotube network thin-film transistors with enhanced inkjet-printed source and drain contact interfaces

    NASA Astrophysics Data System (ADS)

    Lee, Yongwoo; Yoon, Jinsu; Choi, Bongsik; Lee, Heesung; Park, Jinhee; Jeon, Minsu; Han, Jungmin; Lee, Jieun; Kim, Yeamin; Kim, Dae Hwan; Kim, Dong Myong; Choi, Sung-Jin

    2017-10-01

    Carbon nanotubes (CNTs) are emerging materials for semiconducting channels in high-performance thin-film transistor (TFT) technology. However, there are concerns regarding the contact resistance (Rcontact) in CNT-TFTs, which limits the ultimate performance, especially the CNT-TFTs with the inkjet-printed source/drain (S/D) electrodes. Thus, the contact interfaces comprising the overlap between CNTs and metal S/D electrodes play a particularly dominant role in determining the performances and degree of variability in the CNT-TFTs with inkjet-printed S/D electrodes. In this work, the CNT-TFTs with improved device performance are demonstrated to enhance contact interfaces by controlling the CNT density at the network channel and underneath the inkjet-printed S/D electrodes during the formation of a CNT network channel. The origin of the improved device performance was systematically investigated by extracting Rcontact in the CNT-TFTs with the enhanced contact interfaces by depositing a high density of CNTs underneath the S/D electrodes, resulting in a 59% reduction in Rcontact; hence, the key performance metrics were correspondingly improved without sacrificing any other device metrics.

  4. Innovative Use of Thighplasty to Improve Prosthesis Fit and Function in a Transfemoral Amputee.

    PubMed

    Kuiken, Todd A; Fey, Nicholas P; Reissman, Timothy; Finucane, Suzanne B; Dumanian, Gregory A

    2018-01-01

    Excess residual limb fat is a common problem that can impair prosthesis control and negatively impact gait. In the general population, thighplasty and liposuction are commonly performed for cosmetic reasons but not specifically to improve function in amputees. The objective of this study was to determine if these procedures could enhance prosthesis fit and function in an overweight above-knee amputee. We evaluated the use of these techniques on a 50-year-old transfemoral amputee who was overweight. The patient underwent presurgical imaging and tests to measure her residual limb tissue distribution, socket-limb interface stiffness, residual femur orientation, lower-extremity function, and prosthesis satisfaction. A medial thighplasty procedure with circumferential liposuction was performed, during which 2,812 g (6.2 lbs.) of subcutaneous fat and skin was removed from her residual limb. Imaging was repeated 5 months postsurgery; functional assessments were repeated 9 months postsurgery. The patient demonstrated notable improvements in socket fit and in performing most functional and walking tests. Her comfortable walking speed increased 13.3%, and her scores for the Sit-to-Stand and Four Square Step tests improved over 20%. Femur alignment in her socket changed from 8.13 to 4.14 degrees, and analysis showed a marked increase in the socket-limb interface stiffness. This study demonstrates the potential of using a routine plastic surgery procedure to modify the intrinsic properties of the limb and to improve functional outcomes in overweight or obese transfemoral amputees. This technique is a potentially attractive option compared with multiple reiterations of sockets, which can be time-consuming and costly.

  5. High Temperature Transparent Furnace Development

    NASA Technical Reports Server (NTRS)

    Bates, Stephen C.

    1997-01-01

    This report describes the use of novel techniques for heat containment that could be used to build a high temperature transparent furnace. The primary objective of the work was to experimentally demonstrate transparent furnace operation at 1200 C. Secondary objectives were to understand furnace operation and furnace component specification to enable the design and construction of a low power prototype furnace for delivery to NASA in a follow-up project. The basic approach of the research was to couple high temperature component design with simple concept demonstration experiments that modify a commercially available transparent furnace rated at lower temperature. A detailed energy balance of the operating transparent furnace was performed, calculating heat losses through the furnace components as a result of conduction, radiation, and convection. The transparent furnace shells and furnace components were redesigned to permit furnace operation at at least 1200 C. Techniques were developed that are expected to lead to significantly improved heat containment compared with current transparent furnaces. The design of a thermal profile in a multizone high temperature transparent furnace design was also addressed. Experiments were performed to verify the energy balance analysis, to demonstrate some of the major furnace improvement techniques developed, and to demonstrate the overall feasibility of a high temperature transparent furnace. The important objective of the research was achieved: to demonstrate the feasibility of operating a transparent furnace at 1200 C.

  6. An Integrated Gate Turnaround Management Concept Leveraging Big Data/Analytics for NAS Performance Improvements

    NASA Technical Reports Server (NTRS)

    Chung, William; Chachad, Girish; Hochstetler, Ronald

    2016-01-01

    The Integrated Gate Turnaround Management (IGTM) concept was developed to improve the gate turnaround performance at the airport by leveraging relevant historical data to support optimization of airport gate operations, which include: taxi to the gate, gate services, push back, taxi to the runway, and takeoff, based on available resources, constraints, and uncertainties. By analyzing events of gate operations, primary performance dependent attributes of these events were identified for the historical data analysis such that performance models can be developed based on uncertainties to support descriptive, predictive, and prescriptive functions. A system architecture was developed to examine system requirements in support of such a concept. An IGTM prototype was developed to demonstrate the concept using a distributed network and collaborative decision tools for stakeholders to meet on time pushback performance under uncertainties.

  7. A Support Vector Machine-Based Gender Identification Using Speech Signal

    NASA Astrophysics Data System (ADS)

    Lee, Kye-Hwan; Kang, Sang-Ick; Kim, Deok-Hwan; Chang, Joon-Hyuk

    We propose an effective voice-based gender identification method using a support vector machine (SVM). The SVM is a binary classification algorithm that classifies two groups by finding the voluntary nonlinear boundary in a feature space and is known to yield high classification performance. In the present work, we compare the identification performance of the SVM with that of a Gaussian mixture model (GMM)-based method using the mel frequency cepstral coefficients (MFCC). A novel approach of incorporating a features fusion scheme based on a combination of the MFCC and the fundamental frequency is proposed with the aim of improving the performance of gender identification. Experimental results demonstrate that the gender identification performance using the SVM is significantly better than that of the GMM-based scheme. Moreover, the performance is substantially improved when the proposed features fusion technique is applied.

  8. Polyoxometalate-modified TiO2 nanotube arrays photoanode materials for enhanced dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Ran; Sun, Zhixia; Zhang, Yuzhuo; Xu, Lin; Li, Na

    2017-10-01

    In this work, we prepared for the first time the TiO2 nanotube arrays (TNAs) photoanode with polyoxometalate(POMs)-modified TiO2 electron-transport layer for improving the performance of zinc phthalocyanine(ZnPc)-sensitized solar cells. The as-prepared POMs/TNAs/ZnPc composite photoanode exhibited higher photovoltaic performances than the TNAs/ZnPc photoanode, so that the power conversion efficiency of the solar cell device based on the POMs/TNAs/ZnPc photoanode displayed a notable improvement of 45%. These results indicated that the POMs play a key role in reducing charge recombination in phthalocyanine-sensitized solar cells, together with TiO2 nanotube arrays being helpful for electron transport. The mechanism of the performance improvement was demonstrated by the measurements of electrochemical impedance spectra and open-circuit voltage decay curves. Although the resulting performance is still below that of the state-of-the-art dye-sensitized solar cells, this study presents a new insight into improving the power conversion efficiency of phthalocyanine-sensitized solar cells via polyoxometalate-modified TiO2 nanotube arrays photoanode.

  9. Undergraduate medical academic performance is improved by scientific training.

    PubMed

    Zhang, Lili; Zhang, Wei; Wu, Chong; Liu, Zhongming; Cai, Yunfei; Cao, Xingguo; He, Yushan; Liu, Guoxiang; Miao, Hongming

    2017-09-01

    The effect of scientific training on course learning in undergraduates is still controversial. In this study, we investigated the academic performance of undergraduate students with and without scientific training. The results show that scientific training improves students' test scores in general medical courses, such as biochemistry and molecular biology, cell biology, physiology, and even English. We classified scientific training into four levels. We found that literature reading could significantly improve students' test scores in general courses. Students who received scientific training carried out experiments more effectively and published articles performed better than their untrained counterparts in biochemistry and molecular biology examinations. The questionnaire survey demonstrated that the trained students were more confident of their course learning, and displayed more interest, motivation and capability in course learning. In summary, undergraduate academic performance is improved by scientific training. Our findings shed light on the novel strategies in the management of undergraduate education in the medical school. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(5):379-384, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

  10. Working memory training using EEG neurofeedback in normal young adults.

    PubMed

    Xiong, Shi; Cheng, Chen; Wu, Xia; Guo, Xiaojuan; Yao, Li; Zhang, Jiacai

    2014-01-01

    Recent studies have shown that working memory (WM) performance can be improved by intensive and adaptive computerized training. Here, we explored the WM training effect using Electroencephalography (EEG) neurofeedback (NF) in normal young adults. In the first study, we identified the EEG features related to WM in normal young adults. The receiver operating characteristic (ROC) curve showed that the power ratio of the theta-to-alpha rhythms in the anterior-parietal region, accurately classified a high percentage of the EEG trials recorded during WM and fixation control (FC) tasks. Based on these results, a second study aimed to assess the training effects of the theta-to-alpha ratio and tested the hypothesis that up-regulating the power ratio can improve working memory behavior. Our results demonstrated that these normal young adults succeeded in improving their WM performance with EEG NF, and the pre- and post-test evaluations also indicated that WM performance increase in experimental group was significantly greater than control groups. In summary, our findings provided preliminarily evidence that WM performance can be improved through learned regulation of the EEG power ratio using EEG NF.

  11. Improving the Performance of PbS Quantum Dot Solar Cells by Optimizing ZnO Window Layer

    NASA Astrophysics Data System (ADS)

    Yang, Xiaokun; Hu, Long; Deng, Hui; Qiao, Keke; Hu, Chao; Liu, Zhiyong; Yuan, Shengjie; Khan, Jahangeer; Li, Dengbing; Tang, Jiang; Song, Haisheng; Cheng, Chun

    2017-04-01

    Comparing with hot researches in absorber layer, window layer has attracted less attention in PbS quantum dot solar cells (QD SCs). Actually, the window layer plays a key role in exciton separation, charge drifting, and so on. Herein, ZnO window layer was systematically investigated for its roles in QD SCs performance. The physical mechanism of improved performance was also explored. It was found that the optimized ZnO films with appropriate thickness and doping concentration can balance the optical and electrical properties, and its energy band align well with the absorber layer for efficient charge extraction. Further characterizations demonstrated that the window layer optimization can help to reduce the surface defects, improve the heterojunction quality, as well as extend the depletion width. Compared with the control devices, the optimized devices have obtained an efficiency of 6.7% with an enhanced V oc of 18%, J sc of 21%, FF of 10%, and power conversion efficiency of 58%. The present work suggests a useful strategy to improve the device performance by optimizing the window layer besides the absorber layer.

  12. Working memory plasticity and aging.

    PubMed

    Rhodes, Rebecca E; Katz, Benjamin

    2017-02-01

    The present research explores how the trajectory of learning on a working memory task changes throughout the life span, and whether gains in working memory performance are exclusively a question of initial working memory capacity (WMC) or whether age exerts an independent effect. In a large, cross-sectional study of younger, middle-aged, and older adults, we examined learning on a widely used working memory task-the dual n-back task-over 20 sessions of practice. We found that, while all age groups improved on the task, older adults demonstrated less improvement on the task, and also reached a lower asymptotic maximum performance than younger adults. After controlling for initial WMC, we found that age exerted independent effects on training gains and asymptotic performance; older adults tended to improve less and reached lower levels of performance than younger adults. The difference between younger and older adults' rates of learning depended in part on initial WMC. These results suggest that age-related effects on working memory include not only effects on capacity, but also plasticity and the ability to improve on a task. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. When Does Stress Help or Harm? The Effects of Stress Controllability and Subjective Stress Response on Stroop Performance

    PubMed Central

    Henderson, Roselinde K.; Snyder, Hannah R.; Gupta, Tina; Banich, Marie T.

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest Stroop improvement. Once again, this pattern was not demonstrated in the group exposed to uncontrollable events. These results suggest that stress controllability and subjective response interact to affect high-level cognitive abilities. Specifically, exposure to moderate, controllable stress benefits performance, but exposure to uncontrollable stress or having a more extreme response to stress tends to harm performance. These findings may provide insights on how to leverage the beneficial effects of stress in a range of settings. PMID:22701442

  14. When does stress help or harm? The effects of stress controllability and subjective stress response on stroop performance.

    PubMed

    Henderson, Roselinde K; Snyder, Hannah R; Gupta, Tina; Banich, Marie T

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual's response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest Stroop improvement. Once again, this pattern was not demonstrated in the group exposed to uncontrollable events. These results suggest that stress controllability and subjective response interact to affect high-level cognitive abilities. Specifically, exposure to moderate, controllable stress benefits performance, but exposure to uncontrollable stress or having a more extreme response to stress tends to harm performance. These findings may provide insights on how to leverage the beneficial effects of stress in a range of settings.

  15. Noise-robust speech triage.

    PubMed

    Bartos, Anthony L; Cipr, Tomas; Nelson, Douglas J; Schwarz, Petr; Banowetz, John; Jerabek, Ladislav

    2018-04-01

    A method is presented in which conventional speech algorithms are applied, with no modifications, to improve their performance in extremely noisy environments. It has been demonstrated that, for eigen-channel algorithms, pre-training multiple speaker identification (SID) models at a lattice of signal-to-noise-ratio (SNR) levels and then performing SID using the appropriate SNR dependent model was successful in mitigating noise at all SNR levels. In those tests, it was found that SID performance was optimized when the SNR of the testing and training data were close or identical. In this current effort multiple i-vector algorithms were used, greatly improving both processing throughput and equal error rate classification accuracy. Using identical approaches in the same noisy environment, performance of SID, language identification, gender identification, and diarization were significantly improved. A critical factor in this improvement is speech activity detection (SAD) that performs reliably in extremely noisy environments, where the speech itself is barely audible. To optimize SAD operation at all SNR levels, two algorithms were employed. The first maximized detection probability at low levels (-10 dB ≤ SNR < +10 dB) using just the voiced speech envelope, and the second exploited features extracted from the original speech to improve overall accuracy at higher quality levels (SNR ≥ +10 dB).

  16. Demonstration of Advanced CO 2 Capture Process Improvements for Coal-Fired Flue Gas

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

    Carroll, John

    This document summarizes the activities of Cooperative Agreement DE-FE0026590, “Demonstration of Advanced CO 2 Capture Process Improvements for Coal-Fired Flue Gas” during the performance period of October 1, 2015 through May 31, 2017. This project was funded by the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL). Southern Company Services, Inc. (SCS) was the prime contractor and co-funder of the project. Mitsubishi Heavy Industries America (MHIA) and AECOM were project team members. The overall project objective was to improve costs, energy requirements, and performance of an existing amine-based CO 2 capture process. This will occur via improvements inmore » three areas: 1. Reboiler design – The first objective of the program was to demonstrate performance of an integrated stripper/reboiler (termed Built-in Reboiler, or BIR) to reduce footprint, capital costs, and integration issues of the current technology. 2. Particulate management – The second objective was to carry out a Particulate Matter Management (PMM) test. This has the potential to reduce operating costs and capital costs due to the reduced or eliminated need for mechanical filtration. 3. Solvent – The third objective was to carry out a new solvent test plan (referred to as NSL) to demonstrate a new solvent (termed New Solvent A), which is expected to reduce regeneration steam. The bulk price is also expected to be lower than KS-1, which is the current solvent used in this process. NSL testing would include baseline testing, optimization, long term testing, solvent reclamation testing, and final inspection. These combine to form the Advanced Carbon Capture (ACC) technology. Much of this work will be applicable to generic solvent processes, especially in regards to improved reboiler design, and focused to meet or exceed the DOE’s overall carbon capture performance goals of 90% CO 2 capture rate with 95% CO 2 purity at a cost of $40/tonne of CO 2 by 2025 and at a cost of electricity (COE) 30% less than baseline CO 2 capture approaches by 2030. This project was divided into two phases. Phase 1 is the planning phase, and Phase 2 is the construction, operations, testing, and analysis phase. A down select occurred after Phase 1. Phase 1 activities were carried out during this reporting period, and therefore, Phase 1 activities are solely considered in this report. The project was not selected for Phase 2 funding.« less

  17. Water electrolysis system refurbishment and testing

    NASA Technical Reports Server (NTRS)

    Greenough, B. M.

    1972-01-01

    The electrolytic oxygen generator for the back-up water electrolysis system in a 90-day manned test was refurbished, improved and subjected to a 182-day bench test. The performance of the system during the test demonstrated the soundness of the basic electrolysis concept, the high development status of the automatic controls which allowed completely hands-off operation, and the capability for orbital operation. Some design improvements are indicated.

  18. Micromotor endoscope catheter for in vivo, ultrahigh-resolution optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Herz, P. R.; Chen, Y.; Aguirre, A. D.; Schneider, K.; Hsiung, P.; Fujimoto, J. G.; Madden, K.; Schmitt, J.; Goodnow, J.; Petersen, C.

    2004-10-01

    A distally actuated, rotational-scanning micromotor endoscope catheter probe is demonstrated for ultrahigh-resolution in vivo endoscopic optical coherence tomography (OCT) imaging. The probe permits focus adjustment for visualization of tissue morphology at varying depths with improved transverse resolution compared with standard OCT imaging probes. The distal actuation avoids nonuniform scanning motion artifacts that are present with other probe designs and can permit a wider range of imaging speeds. Ultrahigh-resolution endoscopic imaging is demonstrated in a rabbit with <4-µm axial resolution by use of a femtosecond Crforsterite laser light source. The micromotor endoscope catheter probe promises to improve OCT imaging performance in future endoscopic imaging applications.

  19. Individualised Expert Feedback is Not Essential for Improving Basic Clinical Skills Performance in Novice Learners: A Randomized Trial.

    PubMed

    Phillips, Alexander W; Matthan, Joanna; Bookless, Lucy R; Whitehead, Ian J; Madhavan, Anantha; Rodham, Paul; Porter, Anna L R; Nesbitt, Craig I; Stansby, Gerard

    To determine whether unsupervised video feedback (UVF) is as effective as direct expert feedback (DEF) in improving clinical skills performance for medical students learning basic surgical skills-intravenous cannulation, catheterization, and suturing. Feedback is a vital component of the learning process, yet great variation persists in its quality, quantity, and methods of delivery. The use of video technology to assist in the provision of feedback has been adopted increasingly. A prospective, blinded randomized trial comparing DEF, an expert reviewing students' performances with subsequent improvement suggestions, and UVF, students reviewing their own performance with an expert teaching video, was carried out. Medical students received an initial teaching lecture on intravenous cannulation, catheterization, and suturing and were then recorded performing the task. They subsequently received either DEF or UVF before reperforming the task. Students' recordings were additionally scored by 2 blinded experts using a validated proforma. A total of 71 medical students were recruited. Cannulation scores improved 4.3% with DEF and 9.5% with UVF (p = 0.044), catheterization scores improved 8.7% with DEF and 8.9% with UVF (p = 0.96), and suturing improved 15.6% with DEF and 13.2% with UVF (p = 0.54). Improvement from baseline scores was significant in all cases (p < 0.05). Video-assisted feedback allows a significant improvement in clinical skills for novices. No significant additional benefit was demonstrated from DEF, and a similar improvement can be obtained using a generic expert video and allowing students to review their own performance. This could have significant implications for the design and delivery of such training. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  20. Ultra-fast escape maneuver of an octopus-inspired robot.

    PubMed

    Weymouth, G D; Subramaniam, V; Triantafyllou, M S

    2015-02-02

    We design and test an octopus-inspired flexible hull robot that demonstrates outstanding fast-starting performance. The robot is hyper-inflated with water, and then rapidly deflates to expel the fluid so as to power the escape maneuver. Using this robot we verify for the first time in laboratory testing that rapid size-change can substantially reduce separation in bluff bodies traveling several body lengths, and recover fluid energy which can be employed to improve the propulsive performance. The robot is found to experience speeds over ten body lengths per second, exceeding that of a similarly propelled optimally streamlined rigid rocket. The peak net thrust force on the robot is more than 2.6 times that on an optimal rigid body performing the same maneuver, experimentally demonstrating large energy recovery and enabling acceleration greater than 14 body lengths per second squared. Finally, over 53% of the available energy is converted into payload kinetic energy, a performance that exceeds the estimated energy conversion efficiency of fast-starting fish. The Reynolds number based on final speed and robot length is [Formula: see text]. We use the experimental data to establish a fundamental deflation scaling parameter [Formula: see text] which characterizes the mechanisms of flow control via shape change. Based on this scaling parameter, we find that the fast-starting performance improves with increasing size.

  1. Demonstration of hetero-gate-dielectric tunneling field-effect transistors (HG TFETs).

    PubMed

    Choi, Woo Young; Lee, Hyun Kook

    2016-01-01

    The steady scaling-down of semiconductor device for improving performance has been the most important issue among researchers. Recently, as low-power consumption becomes one of the most important requirements, there have been many researches about novel devices for low-power consumption. Though scaling supply voltage is the most effective way for low-power consumption, performance degradation is occurred for metal-oxide-semiconductor field-effect transistors (MOSFETs) when supply voltage is reduced because subthreshold swing (SS) of MOSFETs cannot be lower than 60 mV/dec. Thus, in this thesis, hetero-gate-dielectric tunneling field-effect transistors (HG TFETs) are investigated as one of the most promising alternatives to MOSFETs. By replacing source-side gate insulator with a high- k material, HG TFETs show higher on-current, suppressed ambipolar current and lower SS than conventional TFETs. Device design optimization through simulation was performed and fabrication based on simulation demonstrated that performance of HG TFETs were better than that of conventional TFETs. Especially, enlargement of gate insulator thickness while etching gate insulator at the source side was improved by introducing HF vapor etch process. In addition, the proposed HG TFETs showed higher performance than our previous results by changing structure of sidewall spacer by high- k etching process.

  2. ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) PROGRAM CASE STUDIES: DEMONSTRATING PROGRAM OUTCOMES

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) Environmental Technology Verification (ETV) Program evaluates the performance of innovative air, water, pollution prevention and monitoring technologies that have the potential to improve human health and the environment. This bookle...

  3. Aerodynamic design via control theory

    NASA Technical Reports Server (NTRS)

    Jameson, Antony

    1988-01-01

    The question of how to modify aerodynamic design in order to improve performance is addressed. Representative examples are given to demonstrate the computational feasibility of using control theory for such a purpose. An introduction and historical survey of the subject is included.

  4. Solid, 3-mirror Fabry-Perot etalon.

    PubMed

    Stephen, Mark; Fahey, Molly; Miller, Ian

    2017-04-01

    We present modeling and performance of a solid, fused silica, 3-mirror Fabry-Perot-type etalon. 3-mirror etalons have been known for decades to have superior theoretical performance but for the first time we demonstrate an etalon with sufficient quality to realize the benefits of the more complex design. 3-mirror etalons have better passband shape and higher contrast ratio enabling significantly improved wavelength separation. We show the optical cavity design and construction of the new etalon and show >95% peak transmission, improved passband shape and 20 dB better out-of-band rejection than a similar 2-mirror etalon.

  5. Vectorization of a Monte Carlo simulation scheme for nonequilibrium gas dynamics

    NASA Technical Reports Server (NTRS)

    Boyd, Iain D.

    1991-01-01

    Significant improvement has been obtained in the numerical performance of a Monte Carlo scheme for the analysis of nonequilibrium gas dynamics through an implementation of the algorithm which takes advantage of vector hardware, as presently demonstrated through application to three different problems. These are (1) a 1D standing-shock wave; (2) the flow of an expanding gas through an axisymmetric nozzle; and (3) the hypersonic flow of Ar gas over a 3D wedge. Problem (3) is illustrative of the greatly increased number of molecules which the simulation may involve, thanks to improved algorithm performance.

  6. Electrolytes for Use in High Energy Lithium-Ion Batteries with Wide Operating Temperature Range

    NASA Technical Reports Server (NTRS)

    Smart, Marshall C.; Ratnakumar, B. V.; West, W. C.; Whitcanack, L. D.; Huang, C.; Soler, J.; Krause, F. C.

    2011-01-01

    Objectives of this work are: (1) Develop advanced Li -ion electrolytes that enable cell operation over a wide temperature range (i.e., -30 to +60C). (2) Improve the high temperature stability and lifetime characteristics of wide operating temperature electrolytes. (3) Improve the high voltage stability of these candidate electrolytes systems to enable operation up to 5V with high specific energy cathode materials. (4) Define the performance limitations at low and high temperature extremes, as well as, life limiting processes. (5) Demonstrate the performance of advanced electrolytes in large capacity prototype cells.

  7. Different paths to high-quality care: three archetypes of top-performing practice sites.

    PubMed

    Feifer, Chris; Nemeth, Lynne; Nietert, Paul J; Wessell, Andrea M; Jenkins, Ruth G; Roylance, Loraine; Ornstein, Steven M

    2007-01-01

    Primary care practices use different approaches in their quest for high-quality care. Previous work in the Practice Partner Research Network (PPRNet) found that improved outcomes are associated with strategies to prioritize performance, involve staff, redesign elements of the delivery system, make patients active partners in guideline adherence, and use tools embedded in the electronic medical record. The aim of this study was to examine variations in the adoption of improvements among sites achieving the best outcomes. This study used an observational case study design. A practice-level measure of adherence to clinical guidelines was used to identify the highest performing practices in a network of internal and family medicine practices participating in a national demonstration project. We analyzed qualitative and quantitative information derived from project documents, field notes, and evaluation questionnaires to develop and compare case studies. Nine cases are described. All use many of the same improvement strategies. Differences in the way improvements are organized define 3 distinct archetypes: the Technophiles, the Motivated Team, and the Care Enterprise. There is no single approach that explains the superior performance of high-performing practices, though each has adopted variations of PPRNet's improvement model. Practices will vary in their path to high-quality care. The archetypes could prove to be a useful guide to other practices selecting an overall quality improvement approach.

  8. Continuous improvement in the Industrial and Management Systems Engineering programme at Kuwait University

    NASA Astrophysics Data System (ADS)

    Aldowaisan, Tariq; Allahverdi, Ali

    2016-07-01

    This paper describes the process employed by the Industrial and Management Systems Engineering programme at Kuwait University to continuously improve the programme. Using a continuous improvement framework, the paper demonstrates how various qualitative and quantitative analyses methods, such as hypothesis testing and control charts, have been applied to the results of four assessment tools and other data sources to improve performance. Important improvements include the need to reconsider two student outcomes as they were difficult to implement in courses. In addition, through benchmarking and the engagement of Alumni and Employers, key decisions were made to improve the curriculum and enhance employability.

  9. An efficient impedance method for induced field evaluation based on a stabilized Bi-conjugate gradient algorithm.

    PubMed

    Wang, Hua; Liu, Feng; Xia, Ling; Crozier, Stuart

    2008-11-21

    This paper presents a stabilized Bi-conjugate gradient algorithm (BiCGstab) that can significantly improve the performance of the impedance method, which has been widely applied to model low-frequency field induction phenomena in voxel phantoms. The improved impedance method offers remarkable computational advantages in terms of convergence performance and memory consumption over the conventional, successive over-relaxation (SOR)-based algorithm. The scheme has been validated against other numerical/analytical solutions on a lossy, multilayered sphere phantom excited by an ideal coil loop. To demonstrate the computational performance and application capability of the developed algorithm, the induced fields inside a human phantom due to a low-frequency hyperthermia device is evaluated. The simulation results show the numerical accuracy and superior performance of the method.

  10. Energy harvesting influences electrochemical performance of microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Lobo, Fernanda Leite; Wang, Xin; Ren, Zhiyong Jason

    2017-07-01

    Microbial fuel cells (MFCs) can be effective power sources for remote sensing, wastewater treatment and environmental remediation, but their performance needs significant improvement. This study systematically analyzes how active harvesting using electrical circuits increased MFC system outputs as compared to passive resistors not only in the traditional maximal power point (MPP) but also in other desired operating points such as the maximum current point (MCP) and the maximum voltage point (MVP). Results show that active harvesting in MPP increased power output by 81-375% and active harvesting in MCP increased Coulombic efficiency by 207-805% compared with resisters operated at the same points. The cyclic voltammograms revealed redox potential shifts and supported the performance data. The findings demonstrate that active harvesting is a very effective approach to improve MFC performance across different operating points.

  11. High Performance Computing Software Applications for Space Situational Awareness

    NASA Astrophysics Data System (ADS)

    Giuliano, C.; Schumacher, P.; Matson, C.; Chun, F.; Duncan, B.; Borelli, K.; Desonia, R.; Gusciora, G.; Roe, K.

    The High Performance Computing Software Applications Institute for Space Situational Awareness (HSAI-SSA) has completed its first full year of applications development. The emphasis of our work in this first year was in improving space surveillance sensor models and image enhancement software. These applications are the Space Surveillance Network Analysis Model (SSNAM), the Air Force Space Fence simulation (SimFence), and physically constrained iterative de-convolution (PCID) image enhancement software tool. Specifically, we have demonstrated order of magnitude speed-up in those codes running on the latest Cray XD-1 Linux supercomputer (Hoku) at the Maui High Performance Computing Center. The software applications improvements that HSAI-SSA has made, has had significant impact to the warfighter and has fundamentally changed the role of high performance computing in SSA.

  12. Improved charging performance of Li-O2 batteries by forming Ba-incorporated Li2O2 as the discharge product

    NASA Astrophysics Data System (ADS)

    Matsuda, Shoichi; Uosaki, Kohei; Nakanishi, Shuji

    2017-06-01

    Although Li-O2 batteries can potentially achieve greater than two-fold higher energy densities than Li-ion batteries, the basic performance of Li-O2 batteries remains poor. In particular, the large over-potential of positive electrode reactions during the charging process results in low round-trip energy efficiency and limited cycle life, and is therefore the main barrier to the practical use of rechargeable Li-O2 batteries. In the present study, we demonstrate that the charging performance of Li-O2 batteries can be significantly improved by simply adding barium (Ba) ions into the electrolyte. Elemental analysis revealed that Ba-incorporated Li2O2 was obtained as the main discharge product of a Li-O2 cell operated in the presence of Ba2+. Notably, the improvement of charging performance was confirmed to originate from the Ba-incorporated Li2O2 deposits, rather than the Ba2+ present in the electrolyte. The present results suggest that the incorporation of heteroatoms into the discharge product is an effective approach for improving the charging performance of Li-O2 batteries.

  13. Discretization in time gives rise to noise-induced improvement of the signal-to-noise ratio in static nonlinearities.

    PubMed

    Davidović, A; Huntington, E H; Frater, M R

    2009-07-01

    For some nonlinear systems the performance can improve with an increasing noise level. Such noise-induced improvement in static nonlinearities is of great interest for practical applications since many systems can be modeled in that way (e.g., sensors, quantizers, limiters, etc.). We present experimental evidence that noise-induced performance improvement occurs in those systems as a consequence of discretization in time with the achievable signal-to-noise ratio (SNR) gain increasing with decreasing ratio of input noise bandwidth and total measurement bandwidth. By modifying the input noise bandwidth, noise-induced improvement with SNR gain larger than unity is demonstrated in a system where it was not previously thought possible. Our experimental results bring closer two different theoretical models for the same class of nonlinearities and shed light on the behavior of static nonlinear discrete-time systems.

  14. Scintillation-Hardened GPS Receiver

    NASA Technical Reports Server (NTRS)

    Stephens, Donald R.

    2015-01-01

    CommLargo, Inc., has developed a scintillation-hardened Global Positioning System (GPS) receiver that improves reliability for low-orbit missions and complies with NASA's Space Telecommunications Radio System (STRS) architecture standards. A software-defined radio (SDR) implementation allows a single hardware element to function as either a conventional radio or as a GPS receiver, providing backup and redundancy for platforms such as the International Space Station (ISS) and high-value remote sensing platforms. The innovation's flexible SDR implementation reduces cost, weight, and power requirements. Scintillation hardening improves mission reliability and variability. In Phase I, CommLargo refactored an open-source GPS software package with Kalman filter-based tracking loops to improve performance during scintillation and also demonstrated improved navigation during a geomagnetic storm. In Phase II, the company generated a new field-programmable gate array (FPGA)-based GPS waveform to demonstrate on NASA's Space Communication and Navigation (SCaN) test bed.

  15. Improvements in Raman Lidar Measurements Using New Interference Filter Technology

    NASA Technical Reports Server (NTRS)

    Whiteman, David N.; Potter, John R.; Tola, Rebecca; Veselovskii, Igor; Cadirola, Martin; Rush, Kurt; Comer, Joseph

    2006-01-01

    Narrow-band interference filters with improved transmission in the ultra-violet have been developed under NASA-funded research and used in the Raman Airborne Spectroscopic Lidar (RASL) in ground-based, upward-looking tests. Measurements were made of atmospheric water vapor, cirrus cloud optical properties and carbon dioxide that improve upon any previously demonstrated using Raman lidar. Daytime boundary and mixed layer profiling of water vapor mixing ratio up to an altitude of approximately 4 h is performed with less than 5% random error using temporal and spatial resolution of 2-minutes and 60 - 210, respectively. Daytime cirrus cloud optical depth and extinction-to-backscatter ratio measurements are made using 1 -minute average. Sufficient signal strength is demonstrated to permit the simultaneous profiling of carbon dioxide and water vapor mixing ratio into the free troposphere during the nighttime. A description of the filter technology developments is provided followed by examples of the improved Raman lidar measurements.

  16. Historical background and design evolution of the transonic aircraft technology supercritical wing

    NASA Technical Reports Server (NTRS)

    Ayers, T. G.; Hallissy, J. B.

    1981-01-01

    Two dimensional wind tunnel test results obtained for supercritical airfoils indicated that substantial improvements in aircraft performance at high subsonic speeds could be achieved by shaping the airfoil to improve the supercritical flow above the upper surface. Significant increases in the drag divergence Mach number, the maximum lift coefficient for buffer onset, and the Mach number for buffet onset at a given lift coefficient were demonstrated for the supercritical airfoil, as compared with a NACA 6 series airfoil of comparable thickness. These trends were corroborated by results from three dimensional wind tunnel and flight tests. Because these indicated extensions of the buffet boundaries could provide significant improvements in the maneuverability of a fighter airplane, an exploratory wind tunnel investigation was initiated which demonstrated that significant aerodynamic improvements could be achieved from the direct substitution of a supercritical airfoil on a variable wing sweep multimission airplane model.

  17. The Yo-Yo IR2 test: physiological response, reliability, and application to elite soccer.

    PubMed

    Oberacker, Lisa M; Davis, Shala E; Haff, G Gregory; Witmer, Chad A; Moir, Gavin L

    2012-10-01

    The purpose of this study was to compare the effects of resistance training performed on either a stable or unstable surface on performance tests in female soccer players. Nineteen National Collegiate Athletic Association Division II female soccer players were assigned to either an unstable training group (UST: 19.0 ± 0.47 years; 1.69 ± 6.4 m; 67.8 ± 7.7 kg) or a stable training group (ST: 19.6 ± 0.49 years; 1.64 ± 3.2 m; 62.7 ± 6.27 kg). Player positions were distributed evenly between the groups. Both the groups followed a 5-week periodized resistance training program designed to develop maximum muscular strength. The groups performed the same exercises during each workout, with the UST performing 2 of the exercises in each session on an unstable surface. Pretraining and posttraining measures of straight-line sprint speed, planned and reactive agility, aerobic capacity, and countermovement vertical jump (CMJ) were taken. Significant main effects for time were reported for straight-line sprint speed, planned agility, and reactive agility with both groups demonstrating improvements during the posttraining testing session. The ST demonstrated a significant increase in CMJ during the posttraining session (change in mean: 0.04 m) in contrast to the decline demonstrated by the UST (change in mean: -0.01 m). Performing resistance training exercises on an unstable surface confers no advantage over traditional resistance training exercises for improving the speed, agility, and aerobic capacity of female soccer players. Furthermore, the use of an unstable surface may inhibit the effects of resistance training on vertical jump height, an important variable in soccer performance.

  18. Zr-doped ceria additives for enhanced PEM fuel cell durability and radical scavenger stability

    DOE PAGES

    Baker, Andrew M.; Williams, Stefan Thurston DuBard; Mukundan, Rangachary; ...

    2017-06-06

    Doped ceria compounds demonstrate excellent radical scavenging abilities and are promising additives to improve the chemical durability of polymer electrolyte membrane (PEM) fuel cells. Here in this paper, Ce 0.85Zr 0.15O 2 (CZO) nanoparticles were incorporated into the cathode catalyst layers (CLs) of PEM fuel cells (based on Nafion XL membranes containing 6.0 μg cm -2 ion-exchanged Ce) at loadings of 10 and 55 μg cm -2. When compared to a CZO-free baseline, CZO-containing membrane electrode assemblies (MEAs) demonstrated extended lifetimes during PEM chemical stability accelerated stress tests (ASTs), exhibiting reduced electrochemical gas crossover, open circuit voltage decay, and fluoridemore » emission rates. The MEA with high CZO loading (55 μg cm -2) demonstrated performance losses, which are attributed to Ce poisoning of the PEM and CL ionomer regions, which is supported by X-ray fluorescence (XRF) analysis. In the MEA with the low CZO loading (10 μg cm -2), both the beginning of life (BOL) performance and the performance after 500 hours of ASTs were nearly identical to the BOL performance of the CZO-free baseline MEA. XRF analysis of the MEA with low CZO loading reveals that the BOL PEM Ce concentrations are preserved after 1408 hours of ASTs and that Ce contents in the cathode CL are not significant enough to reduce performance. Therefore, employing a highly effective radical scavenger such as CZO, at a loading of 10 μg cm -2 in the cathode CL, dramatically mitigates degradation effects, which improves MEA chemical durability and minimizes performance losses.« less

  19. Zr-doped ceria additives for enhanced PEM fuel cell durability and radical scavenger stability

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

    Baker, Andrew M.; Williams, Stefan Thurston DuBard; Mukundan, Rangachary

    Doped ceria compounds demonstrate excellent radical scavenging abilities and are promising additives to improve the chemical durability of polymer electrolyte membrane (PEM) fuel cells. Here in this paper, Ce 0.85Zr 0.15O 2 (CZO) nanoparticles were incorporated into the cathode catalyst layers (CLs) of PEM fuel cells (based on Nafion XL membranes containing 6.0 μg cm -2 ion-exchanged Ce) at loadings of 10 and 55 μg cm -2. When compared to a CZO-free baseline, CZO-containing membrane electrode assemblies (MEAs) demonstrated extended lifetimes during PEM chemical stability accelerated stress tests (ASTs), exhibiting reduced electrochemical gas crossover, open circuit voltage decay, and fluoridemore » emission rates. The MEA with high CZO loading (55 μg cm -2) demonstrated performance losses, which are attributed to Ce poisoning of the PEM and CL ionomer regions, which is supported by X-ray fluorescence (XRF) analysis. In the MEA with the low CZO loading (10 μg cm -2), both the beginning of life (BOL) performance and the performance after 500 hours of ASTs were nearly identical to the BOL performance of the CZO-free baseline MEA. XRF analysis of the MEA with low CZO loading reveals that the BOL PEM Ce concentrations are preserved after 1408 hours of ASTs and that Ce contents in the cathode CL are not significant enough to reduce performance. Therefore, employing a highly effective radical scavenger such as CZO, at a loading of 10 μg cm -2 in the cathode CL, dramatically mitigates degradation effects, which improves MEA chemical durability and minimizes performance losses.« less

  20. Efficiency Enhancement of Perovskite Solar Cells by Pumping Away the Solvent of Precursor Film Before Annealing.

    PubMed

    Xu, Qing-Yang; Yuan, Da-Xing; Mu, Hao-Ran; Igbari, Femi; Bao, Qiaoliang; Liao, Liang-Sheng

    2016-12-01

    A new approach to improve the quality of MAPbI3 - x Cl x perovskite film was demonstrated. It involves annealing the precursor film after pumping away the solvent, which can decrease the influence of solvent evaporation rate for the growth of the MAPbI3 - x Cl x perovskite film. The resulting film showed improved morphology, stronger absorption, fewer crystal defects, and smaller charge transfer resistance. The corresponding device demonstrated enhanced performance when compared with a reference device. The averaged value of power conversion efficiency increased from 10.61 to 12.56 %, and a champion efficiency of 14.0 % was achieved. This work paves a new way to improve the efficiency of perovskite solar cells.

  1. Graduate students' teaching experiences improve their methodological research skills.

    PubMed

    Feldon, David F; Peugh, James; Timmerman, Briana E; Maher, Michelle A; Hurst, Melissa; Strickland, Denise; Gilmore, Joanna A; Stiegelmeyer, Cindy

    2011-08-19

    Science, technology, engineering, and mathematics (STEM) graduate students are often encouraged to maximize their engagement with supervised research and minimize teaching obligations. However, the process of teaching students engaged in inquiry provides practice in the application of important research skills. Using a performance rubric, we compared the quality of methodological skills demonstrated in written research proposals for two groups of early career graduate students (those with both teaching and research responsibilities and those with only research responsibilities) at the beginning and end of an academic year. After statistically controlling for preexisting differences between groups, students who both taught and conducted research demonstrate significantly greater improvement in their abilities to generate testable hypotheses and design valid experiments. These results indicate that teaching experience can contribute substantially to the improvement of essential research skills.

  2. Improving Efficiency While Improving Patient Care in a Student-Run Free Clinic.

    PubMed

    Lee, Jason S; Combs, Kristen; Pasarica, Magdalena

    2017-01-01

    Student-run free clinics (SRFCs) have the capacity to decrease health care inequity in underserved populations. These facilities can benefit from improved patient experience and outcomes. We implemented a series of quality improvement interventions with the objectives to decrease patient wait times and to increase the variety of services provided. A needs assessment was performed. Problems related to time management, communication between staff and providers, clinic resources, and methods for assessing clinic performance were identified as targets to reduce wait times and improve the variety of services provided. Seventeen interventions were designed and implemented over a 2-month period. The interventions resulted in improved efficiency for clinic operations and reduced patient wait times. The number of specialty providers, patient visits for specialty care, lifestyle education visits for disease prevention and treatment, free medications, and free laboratory investigations increased to achieve the goal of improving the availability and the variety of services provided. We demonstrated that it is feasible to implement successful quality improvement interventions in SRFCs to decrease patient wait times and to increase the variety of services provided. We believe that the changes we implemented can serve as a model for other SRFCs to improve their performance. © Copyright 2017 by the American Board of Family Medicine.

  3. Effect of hysteretic and non-hysteretic negative capacitance on tunnel FETs DC performance

    NASA Astrophysics Data System (ADS)

    Saeidi, Ali; Jazaeri, Farzan; Stolichnov, Igor; Luong, Gia V.; Zhao, Qing-Tai; Mantl, Siegfried; Ionescu, Adrian M.

    2018-03-01

    This work experimentally demonstrates that the negative capacitance effect can be used to significantly improve the key figures of merit of tunnel field effect transistor (FET) switches. In the proposed approach, a matching condition is fulfilled between a trained-polycrystalline PZT capacitor and the tunnel FET (TFET) gate capacitance fabricated on a strained silicon-nanowire technology. We report a non-hysteretic switch configuration by combining a homojunction TFET and a negative capacitance effect booster, suitable for logic applications, for which the on-current is increased by a factor of 100, the transconductance by 2 orders of magnitude, and the low swing region is extended. The operation of a hysteretic negative capacitance TFET, when the matching condition for the negative capacitance is fulfilled only in a limited region of operation, is also reported and discussed. In this late case, a limited improvement in the device performance is observed. Overall, the paper demonstrates the main beneficial effects of negative capacitance on TFETs are the overdrive and transconductance amplification, which exactly address the most limiting performances of current TFETs.

  4. New perspective on single-radiator multiple-port antennas for adaptive beamforming applications.

    PubMed

    Byun, Gangil; Choo, Hosung

    2017-01-01

    One of the most challenging problems in recent antenna engineering fields is to achieve highly reliable beamforming capabilities in an extremely restricted space of small handheld devices. In this paper, we introduce a new perspective on single-radiator multiple-port (SRMP) antenna to alter the traditional approach of multiple-antenna arrays for improving beamforming performances with reduced aperture sizes. The major contribution of this paper is to demonstrate the beamforming capability of the SRMP antenna for use as an extremely miniaturized front-end component in more sophisticated beamforming applications. To examine the beamforming capability, the radiation properties and the array factor of the SRMP antenna are theoretically formulated for electromagnetic characterization and are used as complex weights to form adaptive array patterns. Then, its fundamental performance limits are rigorously explored through enumerative studies by varying the dielectric constant of the substrate, and field tests are conducted using a beamforming hardware to confirm the feasibility. The results demonstrate that the new perspective of the SRMP antenna allows for improved beamforming performances with the ability of maintaining consistently smaller aperture sizes compared to the traditional multiple-antenna arrays.

  5. Creative group performances to assess core competencies in a first-year patient-centered medicine course

    PubMed Central

    Terregino, Carol A.; Saks, Norma S.

    2010-01-01

    Introduction A novel assessment of systems-based practice and practice-based learning and improvement learning objectives, implemented in a first-year patient-centered medicine course, is qualitatively described. Methods Student learning communities were asked to creatively demonstrate a problem and solution for health care delivery. Skits, filmed performances, plays, and documentaries were chosen by the students. Video recordings were reviewed for themes and the presence of course competencies. Results All performances demonstrated not only the index competencies of team work and facilitation of the learning of others, but many other core objectives of the course. The assignment was rated positively both by the faculty and the students, and has been added to the assessment modalities of the course. PMID:20174597

  6. Creative group performances to assess core competencies in a first-year patient-centered medicine course.

    PubMed

    Terregino, Carol A; Saks, Norma S

    2010-02-15

    A novel assessment of systems-based practice and practice-based learning and improvement learning objectives, implemented in a first-year patient-centered medicine course, is qualitatively described. Student learning communities were asked to creatively demonstrate a problem and solution for health care delivery. Skits, filmed performances, plays, and documentaries were chosen by the students. Video recordings were reviewed for themes and the presence of course competencies. All performances demonstrated not only the index competencies of team work and facilitation of the learning of others, but many other core objectives of the course. The assignment was rated positively both by the faculty and the students, and has been added to the assessment modalities of the course.

  7. Effects of equivalent series resistance on the noise mitigation performance of piezoelectric shunt damping

    NASA Astrophysics Data System (ADS)

    Lai, Szu Cheng; Sharifzadeh Mirshekarloo, Meysam; Yao, Kui

    2017-05-01

    Piezoelectric shunt damping (PSD) utilizes an electrically-shunted piezoelectric damper attached on a panel structure to suppress the transmission of acoustic noise. The paper develops an understanding on the effects of equivalent series resistance (ESR) of the piezoelectric damper in a PSD system on noise mitigation performance, and demonstrates that an increased ESR leads to a significant rise in the noise transmissibility due to reduction in the system’s mechanical damping. It is further demonstrated with experimental results that ESR effects can be compensated in the shunt circuit to significantly improve the noise mitigation performance. A theoretical electrical equivalent model of the PSD incorporating the ESR is established for quantitative analysis of ESR effects on noise mitigation.

  8. Small Engine Technology (SET) Task 23 ANOPP Noise Prediction for Small Engines, Wing Reflection Code

    NASA Technical Reports Server (NTRS)

    Lieber, Lysbeth; Brown, Daniel; Golub, Robert A. (Technical Monitor)

    2000-01-01

    The work performed under Task 23 consisted of the development and demonstration of improvements for the NASA Aircraft Noise Prediction Program (ANOPP), specifically targeted to the modeling of engine noise enhancement due to wing reflection. This report focuses on development of the model and procedure to predict the effects of wing reflection, and the demonstration of the procedure, using a representative wing/engine configuration.

  9. Tuning Monotonic Basin Hopping: Improving the Efficiency of Stochastic Search as Applied to Low-Thrust Trajectory Optimization

    NASA Technical Reports Server (NTRS)

    Englander, Jacob; Englander, Arnold

    2014-01-01

    Trajectory optimization methods using MBH have become well developed during the past decade. An essential component of MBH is a controlled random search through the multi-dimensional space of possible solutions. Historically, the randomness has been generated by drawing RVs from a uniform probability distribution. Here, we investigate the generating the randomness by drawing the RVs from Cauchy and Pareto distributions, chosen because of their characteristic long tails. We demonstrate that using Cauchy distributions (as first suggested by Englander significantly improves MBH performance, and that Pareto distributions provide even greater improvements. Improved performance is defined in terms of efficiency and robustness, where efficiency is finding better solutions in less time, and robustness is efficiency that is undiminished by (a) the boundary conditions and internal constraints of the optimization problem being solved, and (b) by variations in the parameters of the probability distribution. Robustness is important for achieving performance improvements that are not problem specific. In this work we show that the performance improvements are the result of how these long-tailed distributions enable MBH to search the solution space faster and more thoroughly. In developing this explanation, we use the concepts of sub-diffusive, normally-diffusive, and super-diffusive RWs originally developed in the field of statistical physics.

  10. Improvement of short-term memory performance in aged beagles by a nutraceutical supplement containing phosphatidylserine, Ginkgo biloba, vitamin E, and pyridoxine

    PubMed Central

    Araujo, Joseph A.; Landsberg, Gary M.; Milgram, Norton W.; Miolo, Alda

    2008-01-01

    Aged dogs demonstrate cognitive decline that is linked to brain aging. The purpose of the present study was to examine if a commercially available nutraceutical supplement that may be neuroprotective and contains phosphatidylserine, Ginkgo biloba, vitamin E, and pyridoxine could improve cognitive function in aged beagles. Nine aged beagles were tested on performance on a delayed-non-matching-to-position task, which is a neuropsychological test of short-term visuospatial memory. All subjects were tested on 5 baseline sessions; then, to assess the supplement, a crossover design was used in which 1 group received the supplement and the other a control substance in the 1st phase, with treatment conditions being reversed in the 2nd phase. Performance accuracy was significantly improved in supplemented dogs compared with control dogs and the effect was long lasting. These findings suggest that the nutraceutical supplement can improve memory in aged dogs. PMID:18481547

  11. Lesion detection and quantification performance of the Tachyon-I time-of-flight PET scanner: phantom and human studies.

    PubMed

    Zhang, Xuezhu; Peng, Qiyu; Zhou, Jian; Huber, Jennifer S; Moses, William W; Qi, Jinyi

    2018-03-16

    The first generation Tachyon PET (Tachyon-I) is a demonstration single-ring PET scanner that reaches a coincidence timing resolution of 314 ps using LSO scintillator crystals coupled to conventional photomultiplier tubes. The objective of this study was to quantify the improvement in both lesion detection and quantification performance resulting from the improved time-of-flight (TOF) capability of the Tachyon-I scanner. We developed a quantitative TOF image reconstruction method for the Tachyon-I and evaluated its TOF gain for lesion detection and quantification. Scans of either a standard NEMA torso phantom or healthy volunteers were used as the normal background data. Separately scanned point source and sphere data were superimposed onto the phantom or human data after accounting for the object attenuation. We used the bootstrap method to generate multiple independent noisy datasets with and without a lesion present. The signal-to-noise ratio (SNR) of a channelized hotelling observer (CHO) was calculated for each lesion size and location combination to evaluate the lesion detection performance. The bias versus standard deviation trade-off of each lesion uptake was also calculated to evaluate the quantification performance. The resulting CHO-SNR measurements showed improved performance in lesion detection with better timing resolution. The detection performance was also dependent on the lesion size and location, in addition to the background object size and shape. The results of bias versus noise trade-off showed that the noise (standard deviation) reduction ratio was about 1.1-1.3 over the TOF 500 ps and 1.5-1.9 over the non-TOF modes, similar to the SNR gains for lesion detection. In conclusion, this Tachyon-I PET study demonstrated the benefit of improved time-of-flight capability on lesion detection and ROI quantification for both phantom and human subjects.

  12. Lesion detection and quantification performance of the Tachyon-I time-of-flight PET scanner: phantom and human studies

    NASA Astrophysics Data System (ADS)

    Zhang, Xuezhu; Peng, Qiyu; Zhou, Jian; Huber, Jennifer S.; Moses, William W.; Qi, Jinyi

    2018-03-01

    The first generation Tachyon PET (Tachyon-I) is a demonstration single-ring PET scanner that reaches a coincidence timing resolution of 314 ps using LSO scintillator crystals coupled to conventional photomultiplier tubes. The objective of this study was to quantify the improvement in both lesion detection and quantification performance resulting from the improved time-of-flight (TOF) capability of the Tachyon-I scanner. We developed a quantitative TOF image reconstruction method for the Tachyon-I and evaluated its TOF gain for lesion detection and quantification. Scans of either a standard NEMA torso phantom or healthy volunteers were used as the normal background data. Separately scanned point source and sphere data were superimposed onto the phantom or human data after accounting for the object attenuation. We used the bootstrap method to generate multiple independent noisy datasets with and without a lesion present. The signal-to-noise ratio (SNR) of a channelized hotelling observer (CHO) was calculated for each lesion size and location combination to evaluate the lesion detection performance. The bias versus standard deviation trade-off of each lesion uptake was also calculated to evaluate the quantification performance. The resulting CHO-SNR measurements showed improved performance in lesion detection with better timing resolution. The detection performance was also dependent on the lesion size and location, in addition to the background object size and shape. The results of bias versus noise trade-off showed that the noise (standard deviation) reduction ratio was about 1.1–1.3 over the TOF 500 ps and 1.5–1.9 over the non-TOF modes, similar to the SNR gains for lesion detection. In conclusion, this Tachyon-I PET study demonstrated the benefit of improved time-of-flight capability on lesion detection and ROI quantification for both phantom and human subjects.

  13. Developing Pharmacy Student Communication Skills through Role-Playing and Active Learning

    PubMed Central

    Zeszotarski, Paula; Ma, Carolyn

    2015-01-01

    Objective. To evaluate the impact on pharmacy students of a communication course, which used role-playing to develop active-learning skills. Design. Students role-playing pharmacists in patient care scenarios were critiqued by students and pharmacist faculty members. Grading was performed using the rubric inspired by Bruce Berger’s Communication Skills for Pharmacists. Written skills were evaluated using student written critique questionnaires. Students completed precourse and postcourse self-assessment surveys. Preceptor evaluations were analyzed for course impact. Assessment. Students demonstrated improvement in oral skills based on role-play scores (45.87/50) after practice sessions. The average score based on the student questionnaire was 9.31/10. Gain was demonstrated in all defined course objectives. Impact on introductory pharmacy practice experience (IPPE) communication objectives was insignificant. Student evaluations for course and teaching strategy reflected a high average. Conclusion. Study results demonstrated improvement in oral and written communication skills that may help improve interprofessional teamwork between pharmacists and other health care providers. PMID:25995519

  14. High-performance ternary blend polymer solar cells involving both energy transfer and hole relay processes.

    PubMed

    Lu, Luyao; Chen, Wei; Xu, Tao; Yu, Luping

    2015-06-04

    The integration of multiple materials with complementary absorptions into a single junction device is regarded as an efficient way to enhance the power conversion efficiency (PCE) of organic solar cells (OSCs). However, because of increased complexity with one more component, only limited high-performance ternary systems have been demonstrated previously. Here we report an efficient ternary blend OSC with a PCE of 9.2%. We show that the third component can reduce surface trap densities in the ternary blend. Detailed studies unravel that the improved performance results from synergistic effects of enlarged open circuit voltage, suppressed trap-assisted recombination, enhanced light absorption, increased hole extraction, efficient energy transfer and better morphology. The working mechanism and high device performance demonstrate new insights and design guidelines for high-performance ternary blend solar cells and suggest that ternary structure is a promising platform to boost the efficiency of OSCs.

  15. Coarse Alignment Technology on Moving base for SINS Based on the Improved Quaternion Filter Algorithm.

    PubMed

    Zhang, Tao; Zhu, Yongyun; Zhou, Feng; Yan, Yaxiong; Tong, Jinwu

    2017-06-17

    Initial alignment of the strapdown inertial navigation system (SINS) is intended to determine the initial attitude matrix in a short time with certain accuracy. The alignment accuracy of the quaternion filter algorithm is remarkable, but the convergence rate is slow. To solve this problem, this paper proposes an improved quaternion filter algorithm for faster initial alignment based on the error model of the quaternion filter algorithm. The improved quaternion filter algorithm constructs the K matrix based on the principle of optimal quaternion algorithm, and rebuilds the measurement model by containing acceleration and velocity errors to make the convergence rate faster. A doppler velocity log (DVL) provides the reference velocity for the improved quaternion filter alignment algorithm. In order to demonstrate the performance of the improved quaternion filter algorithm in the field, a turntable experiment and a vehicle test are carried out. The results of the experiments show that the convergence rate of the proposed improved quaternion filter is faster than that of the tradition quaternion filter algorithm. In addition, the improved quaternion filter algorithm also demonstrates advantages in terms of correctness, effectiveness, and practicability.

  16. Quantitative optical imaging and sensing by joint design of point spread functions and estimation algorithms

    NASA Astrophysics Data System (ADS)

    Quirin, Sean Albert

    The joint application of tailored optical Point Spread Functions (PSF) and estimation methods is an important tool for designing quantitative imaging and sensing solutions. By enhancing the information transfer encoded by the optical waves into an image, matched post-processing algorithms are able to complete tasks with improved performance relative to conventional designs. In this thesis, new engineered PSF solutions with image processing algorithms are introduced and demonstrated for quantitative imaging using information-efficient signal processing tools and/or optical-efficient experimental implementations. The use of a 3D engineered PSF, the Double-Helix (DH-PSF), is applied as one solution for three-dimensional, super-resolution fluorescence microscopy. The DH-PSF is a tailored PSF which was engineered to have enhanced information transfer for the task of localizing point sources in three dimensions. Both an information- and optical-efficient implementation of the DH-PSF microscope are demonstrated here for the first time. This microscope is applied to image single-molecules and micro-tubules located within a biological sample. A joint imaging/axial-ranging modality is demonstrated for application to quantifying sources of extended transverse and axial extent. The proposed implementation has improved optical-efficiency relative to prior designs due to the use of serialized cycling through select engineered PSFs. This system is demonstrated for passive-ranging, extended Depth-of-Field imaging and digital refocusing of random objects under broadband illumination. Although the serialized engineered PSF solution is an improvement over prior designs for the joint imaging/passive-ranging modality, it requires the use of multiple PSFs---a potentially significant constraint. Therefore an alternative design is proposed, the Single-Helix PSF, where only one engineered PSF is necessary and the chromatic behavior of objects under broadband illumination provides the necessary information transfer. The matched estimation algorithms are introduced along with an optically-efficient experimental system to image and passively estimate the distance to a test object. An engineered PSF solution is proposed for improving the sensitivity of optical wave-front sensing using a Shack-Hartmann Wave-front Sensor (SHWFS). The performance limits of the classical SHWFS design are evaluated and the engineered PSF system design is demonstrated to enhance performance. This system is fabricated and the mechanism for additional information transfer is identified.

  17. Acoustic Analysis and Electroglottography in Elite Vocal Performers.

    PubMed

    Villafuerte-Gonzalez, Rocio; Valadez-Jimenez, Victor M; Sierra-Ramirez, Jose A; Ysunza, Pablo Antonio; Chavarria-Villafuerte, Karen; Hernandez-Lopez, Xochiquetzal

    2017-05-01

    Acoustic analysis of voice (AAV) and electroglottography (EGG) have been used for assessing vocal quality in patients with voice disorders. The effectiveness of these procedures for detecting mild disturbances in vocal quality in elite vocal performers has been controversial. To compare acoustic parameters obtained by AAV and EGG before and after vocal training to determine the effectiveness of these procedures for detecting vocal improvements in elite vocal performers. Thirty-three elite vocal performers were studied. The study group included 14 males and 19 females, ages 18-40 years, without a history of voice disorders. Acoustic parameters were obtained through AAV and EGG before and after vocal training using the Linklater method. Nonsignificant differences (P > 0.05) were found between values of fundamental frequency (F 0 ), shimmer, and jitter obtained by both procedures before vocal training. Mean F 0 was similar after vocal training. Jitter percentage as measured by AAV showed nonsignificant differences (P > 0.05) before and after vocal training. Shimmer percentage as measured by AAV demonstrated a significant reduction (P < 0.05) after vocal training. As measured by EGG after vocal training, shimmer and jitter were significantly reduced (P < 0.05); open quotient was significantly increased (P < 0.05); and irregularity was significantly reduced (P < 0.05). AAV and EGG were effective for detecting improvements in vocal function after vocal training in male and female elite vocal performers undergoing vocal training. EGG demonstrated better efficacy for detecting improvements and provided additional parameters as compared to AAV. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  18. Full parabolic trough qualification from prototype to demonstration loop

    NASA Astrophysics Data System (ADS)

    Janotte, Nicole; Lüpfert, Eckhard; Pottler, Klaus; Schmitz, Mark

    2017-06-01

    On the example of the HelioTrough® collector development the full accompanying and supporting qualification program for large-scale parabolic trough collectors for solar thermal power plants is described from prototype to demonstration loop scale. In the evaluation process the actual state and the optimization potential are assessed. This includes the optical and geometrical performance determined by concentrator shape, deformation, assembly quality and local intercept factor values. Furthermore, its mechanical performance in terms of tracking accuracy and torsional stiffness and its thermal system performance on the basis of the overall thermal output and heat loss are evaluated. Demonstration loop tests deliver results of collector modules statistical slope deviation of 1.9 to 2.6 mrad, intercept factor above 98%, peak optical performance of 81.6% and heat loss coefficients from field tests. The benefit of such a closely monitored development lies in prompt feedback on strengths, weaknesses and potential improvements on the new product at any development stage from first module tests until demonstration loop evaluation. The product developer takes advantage of the achieved technical maturity, already before the implementation in a commercial power plant. The well-understood performance characteristics allow the reduction of safety margins making the new HelioTrough collector competitive from the start.

  19. High-performance alkaline direct methanol fuel cell using a nitrogen-postdoped anode.

    PubMed

    Joghee, Prabhuram; Pylypenko, Svitlana; Wood, Kevin; Bender, Guido; O'Hayre, Ryan

    2014-07-01

    A commercial PtRu/C catalyst postdoped with nitrogen demonstrates a significantly higher performance (~10-20% improvement) in the anode of an alkaline direct methanol fuel cell than an unmodified commercial PtRu/C catalyst control. The enhanced performance shown herein is attributed at least partially to the increased electrochemical surface area of the PtRu/C after postdoping with nitrogen. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Design, Fabrication, and Characterization of Carbon Nanotube Field Emission Devices for Advanced Applications

    NASA Astrophysics Data System (ADS)

    Radauscher, Erich Justin

    Carbon nanotubes (CNTs) have recently emerged as promising candidates for electron field emission (FE) cathodes in integrated FE devices. These nanostructured carbon materials possess exceptional properties and their synthesis can be thoroughly controlled. Their integration into advanced electronic devices, including not only FE cathodes, but sensors, energy storage devices, and circuit components, has seen rapid growth in recent years. The results of the studies presented here demonstrate that the CNT field emitter is an excellent candidate for next generation vacuum microelectronics and related electron emission devices in several advanced applications. The work presented in this study addresses determining factors that currently confine the performance and application of CNT-FE devices. Characterization studies and improvements to the FE properties of CNTs, along with Micro-Electro-Mechanical Systems (MEMS) design and fabrication, were utilized in achieving these goals. Important performance limiting parameters, including emitter lifetime and failure from poor substrate adhesion, are examined. The compatibility and integration of CNT emitters with the governing MEMS substrate (i.e., polycrystalline silicon), and its impact on these performance limiting parameters, are reported. CNT growth mechanisms and kinetics were investigated and compared to silicon (100) to improve the design of CNT emitter integrated MEMS based electronic devices, specifically in vacuum microelectronic device (VMD) applications. Improved growth allowed for design and development of novel cold-cathode FE devices utilizing CNT field emitters. A chemical ionization (CI) source based on a CNT-FE electron source was developed and evaluated in a commercial desktop mass spectrometer for explosives trace detection. This work demonstrated the first reported use of a CNT-based ion source capable of collecting CI mass spectra. The CNT-FE source demonstrated low power requirements, pulsing capabilities, and average lifetimes of over 320 hours when operated in constant emission mode under elevated pressures, without sacrificing performance. Additionally, a novel packaged ion source for miniature mass spectrometer applications using CNT emitters, a MEMS based Nier-type geometry, and a Low Temperature Cofired Ceramic (LTCC) 3D scaffold with integrated ion optics were developed and characterized. While previous research has shown other devices capable of collecting ion currents on chip, this LTCC packaged MEMS micro-ion source demonstrated improvements in energy and angular dispersion as well as the ability to direct the ions out of the packaged source and towards a mass analyzer. Simulations and experimental design, fabrication, and characterization were used to make these improvements. Finally, novel CNT-FE devices were developed to investigate their potential to perform as active circuit elements in VMD circuits. Difficulty integrating devices at micron-scales has hindered the use of vacuum electronic devices in integrated circuits, despite the unique advantages they offer in select applications. Using a combination of particle trajectory simulation and experimental characterization, device performance in an integrated platform was investigated. Solutions to the difficulties in operating multiple devices in close proximity and enhancing electron transmission (i.e., reducing grid loss) are explored in detail. A systematic and iterative process was used to develop isolation structures that reduced crosstalk between neighboring devices from 15% on average, to nearly zero. Innovative geometries and a new operational mode reduced grid loss by nearly threefold, thereby improving transmission of the emitted cathode current to the anode from 25% in initial designs to 70% on average. These performance enhancements are important enablers for larger scale integration and for the realization of complex vacuum microelectronic circuits.

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

    PubMed Central

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

    2018-01-01

    Purpose In recognition of the importance of performance measurement and MCH epidemiology leadership to quality improvement (QI) efforts, a plenary session dedicated to this topic was presented at the 2014 CityMatCH Leadership and MCH Epidemiology Conference. This paper summarizes the session and provides two applications of performance measurement to QI in MCH. Description Performance measures addressing processes of care are ubiquitous in the current health system landscape and the MCH community is increasingly applying QI processes, such as Plan-Do-Study-Act (PDSA) cycles, to improve the effectiveness and efficiency of systems impacting MCH populations. QI is maximally effective when well-defined performance measures are used to monitor change. Assessment MCH epidemiologists provide leadership to QI initiatives by identifying population-based outcomes that would benefit from QI, defining and implementing performance measures, assessing and improving data quality and timeliness, reporting variability in measures throughout PDSA cycles, evaluating QI initiative impact, and translating findings to stakeholders. MCH epidemiologists can also ensure that QI initiatives are aligned with MCH priorities at the local, state and federal levels. Two examples of this work, one highlighting use of a contraceptive service performance measure and another describing QI for peripartum hemorrhage prevention, demonstrate MCH epidemiologists’ contributions throughout. Challenges remain in applying QI to complex community and systems-level interventions, including those aimed at improving access to quality care. Conclusion MCH epidemiologists provide leadership to QI initiatives by ensuring they are data-informed and supportive of a common MCH agenda, thereby optimizing the potential to improve MCH outcomes. PMID:27423235

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

    PubMed

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

    2016-11-01

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

  3. Expected energy-based restricted Boltzmann machine for classification.

    PubMed

    Elfwing, S; Uchibe, E; Doya, K

    2015-04-01

    In classification tasks, restricted Boltzmann machines (RBMs) have predominantly been used in the first stage, either as feature extractors or to provide initialization of neural networks. In this study, we propose a discriminative learning approach to provide a self-contained RBM method for classification, inspired by free-energy based function approximation (FE-RBM), originally proposed for reinforcement learning. For classification, the FE-RBM method computes the output for an input vector and a class vector by the negative free energy of an RBM. Learning is achieved by stochastic gradient-descent using a mean-squared error training objective. In an earlier study, we demonstrated that the performance and the robustness of FE-RBM function approximation can be improved by scaling the free energy by a constant that is related to the size of network. In this study, we propose that the learning performance of RBM function approximation can be further improved by computing the output by the negative expected energy (EE-RBM), instead of the negative free energy. To create a deep learning architecture, we stack several RBMs on top of each other. We also connect the class nodes to all hidden layers to try to improve the performance even further. We validate the classification performance of EE-RBM using the MNIST data set and the NORB data set, achieving competitive performance compared with other classifiers such as standard neural networks, deep belief networks, classification RBMs, and support vector machines. The purpose of using the NORB data set is to demonstrate that EE-RBM with binary input nodes can achieve high performance in the continuous input domain. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Effects of caffeine and carbohydrate mouth rinses on repeated sprint performance.

    PubMed

    Beaven, C Martyn; Maulder, Peter; Pooley, Adrian; Kilduff, Liam; Cook, Christian

    2013-06-01

    Our purpose was to examine the effectiveness of carbohydrate and caffeine mouth rinses in enhancing repeated sprint ability. Previously, studies have shown that a carbohydrate mouth rinse (without ingestion) has beneficial effects on endurance performance that are related to changes in brain activity. Caffeine ingestion has also demonstrated positive effects on sprint performance. However, the effects of carbohydrate or caffeine mouth rinses on intermittent sprints have not been examined previously. Twelve males performed 5 × 6-s sprints interspersed with 24 s of active recovery on a cycle ergometer. Twenty-five milliliters of either a noncaloric placebo, a 6% glucose, or a 1.2% caffeine solution was rinsed in the mouth for 5 s prior to each sprint in a double-blinded and balanced cross-over design. Postexercise maximal heart rate and perceived exertion were recorded, along with power measures. A second experiment compared a combined caffeine-carbohydrate rinse with carbohydrate only. Compared with the placebo mouth rinse, carbohydrate substantially increased peak power in sprint 1 (22.1 ± 19.5 W; Cohen's effect size (ES), 0.81), and both caffeine (26.9 ± 26.9 W; ES, 0.71) and carbohydrate (39.1 ± 25.8 W; ES, 1.08) improved mean power in sprint 1. Experiment 2 demonstrated that a combination of caffeine and carbohydrate improved sprint 1 power production compared with carbohydrate alone (36.0 ± 37.3 W; ES, 0.81). We conclude that carbohydrate and (or) caffeine mouth rinses may rapidly enhance power production, which could have benefits for specific short sprint exercise performance. The ability of a mouth-rinse intervention to rapidly improve maximal exercise performance in the absence of fatigue suggests a central mechanism.

  5. Applying dynamic data collection to improve dry electrode system performance for a P300-based brain-computer interface

    NASA Astrophysics Data System (ADS)

    Clements, J. M.; Sellers, E. W.; Ryan, D. B.; Caves, K.; Collins, L. M.; Throckmorton, C. S.

    2016-12-01

    Objective. Dry electrodes have an advantage over gel-based ‘wet’ electrodes by providing quicker set-up time for electroencephalography recording; however, the potentially poorer contact can result in noisier recordings. We examine the impact that this may have on brain-computer interface communication and potential approaches for mitigation. Approach. We present a performance comparison of wet and dry electrodes for use with the P300 speller system in both healthy participants and participants with communication disabilities (ALS and PLS), and investigate the potential for a data-driven dynamic data collection algorithm to compensate for the lower signal-to-noise ratio (SNR) in dry systems. Main results. Performance results from sixteen healthy participants obtained in the standard static data collection environment demonstrate a substantial loss in accuracy with the dry system. Using a dynamic stopping algorithm, performance may have been improved by collecting more data in the dry system for ten healthy participants and eight participants with communication disabilities; however, the algorithm did not fully compensate for the lower SNR of the dry system. An analysis of the wet and dry system recordings revealed that delta and theta frequency band power (0.1-4 Hz and 4-8 Hz, respectively) are consistently higher in dry system recordings across participants, indicating that transient and drift artifacts may be an issue for dry systems. Significance. Using dry electrodes is desirable for reduced set-up time; however, this study demonstrates that online performance is significantly poorer than for wet electrodes for users with and without disabilities. We test a new application of dynamic stopping algorithms to compensate for poorer SNR. Dynamic stopping improved dry system performance; however, further signal processing efforts are likely necessary for full mitigation.

  6. Effects of ongoing task context and target typicality on prospective memory performance: the importance of associative cueing

    NASA Technical Reports Server (NTRS)

    Nowinski, Jessica Lang; Dismukes, Key R.

    2005-01-01

    Two experiments examined whether prospective memory performance is influenced by contextual cues. In our automatic activation model, any information available at encoding and retrieval should aid recall of the prospective task. The first experiment demonstrated an effect of the ongoing task context; performance was better when information about the ongoing task present at retrieval was available at encoding. Performance was also improved by a strong association between the prospective memory target as it was presented at retrieval and the intention as it was encoded. Experiment 2 demonstrated boundary conditions of the ongoing task context effect, which implicate the association between the ongoing and prospective tasks formed at encoding as the source of the context effect. The results of this study are consistent with predictions based on automatic activation of intentions.

  7. Fixations to the eyes aids in facial encoding; covertly attending to the eyes does not.

    PubMed

    Laidlaw, Kaitlin E W; Kingstone, Alan

    2017-02-01

    When looking at images of faces, people will often focus their fixations on the eyes. It has previously been demonstrated that the eyes convey important information that may improve later facial recognition. Whether this advantage requires that the eyes be fixated, or merely attended to covertly (i.e. while looking elsewhere), is unclear from previous work. While attending to the eyes covertly without fixating them may be sufficient, the act of using overt attention to fixate the eyes may improve the processing of important details used for later recognition. In the present study, participants were shown a series of faces and, in Experiment 1, asked to attend to them normally while avoiding looking at either the eyes or, as a control, the mouth (overt attentional avoidance condition); or in Experiment 2 fixate the center of the face while covertly attending to either the eyes or the mouth (covert attention condition). After the first phase, participants were asked to perform an old/new face recognition task. We demonstrate that a) when fixations to the eyes are avoided during initial viewing then subsequent face discrimination suffers, and b) covert attention to the eyes alone is insufficient to improve face discrimination performance. Together, these findings demonstrate that fixating the eyes provides an encoding advantage that is not availed by covert attention alone. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Martial Art Training and Cognitive Performance in Middle-Aged Adults.

    PubMed

    Douris, Peter; Douris, Christopher; Balder, Nicole; LaCasse, Michael; Rand, Amir; Tarapore, Freya; Zhuchkan, Aleskey; Handrakis, John

    2015-09-29

    Cognitive performance includes the processes of attention, memory, processing speed, and executive functioning, which typically declines with aging. Previous research has demonstrated that aerobic and resistance exercise improves cognitive performance immediately following exercise. However, there is limited research examining the effect that a cognitively complex exercise such as martial art training has on these cognitive processes. Our study compared the acute effects of 2 types of martial art training to aerobic exercise on cognitive performance in middle-aged adults. We utilized a repeated measures design with the order of the 3 exercise conditions randomly assigned and counterbalanced. Ten recreational middle-aged martial artists (mean age = 53.5 ± 8.6 years) participated in 3 treatment conditions: a typical martial art class, an atypical martial art class, and a one-hour walk at a self-selected speed. Cognitive performance was assessed by the Stroop Color and Word test. While all 3 exercise conditions improved attention and processing speed, only the 2 martial art conditions improved the highest order of cognitive performance, executive function. The effect of the 2 martial art conditions on executive function was not different. The improvement in executive function may be due to the increased cortical demand required by the more complex, coordinated motor tasks of martial art exercise compared to the more repetitive actions of walking.

  9. Martial Art Training and Cognitive Performance in Middle-Aged Adults

    PubMed Central

    Douris, Peter; Douris, Christopher; Balder, Nicole; LaCasse, Michael; Rand, Amir; Tarapore, Freya; Zhuchkan, Aleskey; Handrakis, John

    2015-01-01

    Cognitive performance includes the processes of attention, memory, processing speed, and executive functioning, which typically declines with aging. Previous research has demonstrated that aerobic and resistance exercise improves cognitive performance immediately following exercise. However, there is limited research examining the effect that a cognitively complex exercise such as martial art training has on these cognitive processes. Our study compared the acute effects of 2 types of martial art training to aerobic exercise on cognitive performance in middle-aged adults. We utilized a repeated measures design with the order of the 3 exercise conditions randomly assigned and counterbalanced. Ten recreational middle-aged martial artists (mean age = 53.5 ± 8.6 years) participated in 3 treatment conditions: a typical martial art class, an atypical martial art class, and a one-hour walk at a self-selected speed. Cognitive performance was assessed by the Stroop Color and Word test. While all 3 exercise conditions improved attention and processing speed, only the 2 martial art conditions improved the highest order of cognitive performance, executive function. The effect of the 2 martial art conditions on executive function was not different. The improvement in executive function may be due to the increased cortical demand required by the more complex, coordinated motor tasks of martial art exercise compared to the more repetitive actions of walking. PMID:26672872

  10. ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) PROGRAM CASE STUDIES: DEMONSTRATING PROGRAM OUTCOMES, VOLUME II

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) Environmental Technology Verification (ETV) Program evaluates the performance of innovative air, water, pollution prevention and monitoring technologies that have the potential to improve human health and the environment. This bookle...

  11. Environmental Technology Verification Program - ETV - Case Studies: Demonstrating Program Outcomes

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) Environmental Technology Verification (ETV) Program evaluates the performance of innovative air, water, pollution prevention and monitoring technologies that have the potential to improve human health and the environment. This cd con...

  12. The Importance of Asthma and Health Programs in Improving Academic Performance

    EPA Pesticide Factsheets

    School air quality has a major impact on asthma and other respiratory illnesses. Airborne allergens or irritants frequently trigger asthma attacks, yet environmental assessments demonstrate that schools often harbor allergen levels at or close to the th

  13. Energy efficient strategy for throughput improvement in wireless sensor networks.

    PubMed

    Jabbar, Sohail; Minhas, Abid Ali; Imran, Muhammad; Khalid, Shehzad; Saleem, Kashif

    2015-01-23

    Network lifetime and throughput are one of the prime concerns while designing routing protocols for wireless sensor networks (WSNs). However, most of the existing schemes are either geared towards prolonging network lifetime or improving throughput. This paper presents an energy efficient routing scheme for throughput improvement in WSN. The proposed scheme exploits multilayer cluster design for energy efficient forwarding node selection, cluster heads rotation and both inter- and intra-cluster routing. To improve throughput, we rotate the role of cluster head among various nodes based on two threshold levels which reduces the number of dropped packets. We conducted simulations in the NS2 simulator to validate the performance of the proposed scheme. Simulation results demonstrate the performance efficiency of the proposed scheme in terms of various metrics compared to similar approaches published in the literature.

  14. Energy Efficient Strategy for Throughput Improvement in Wireless Sensor Networks

    PubMed Central

    Jabbar, Sohail; Minhas, Abid Ali; Imran, Muhammad; Khalid, Shehzad; Saleem, Kashif

    2015-01-01

    Network lifetime and throughput are one of the prime concerns while designing routing protocols for wireless sensor networks (WSNs). However, most of the existing schemes are either geared towards prolonging network lifetime or improving throughput. This paper presents an energy efficient routing scheme for throughput improvement in WSN. The proposed scheme exploits multilayer cluster design for energy efficient forwarding node selection, cluster heads rotation and both inter- and intra-cluster routing. To improve throughput, we rotate the role of cluster head among various nodes based on two threshold levels which reduces the number of dropped packets. We conducted simulations in the NS2 simulator to validate the performance of the proposed scheme. Simulation results demonstrate the performance efficiency of the proposed scheme in terms of various metrics compared to similar approaches published in the literature. PMID:25625902

  15. Gait and balance of transfemoral amputees using passive mechanical and microprocessor-controlled prosthetic knees.

    PubMed

    Kaufman, K R; Levine, J A; Brey, R H; Iverson, B K; McCrady, S K; Padgett, D J; Joyner, M J

    2007-10-01

    Microprocessor-controlled knee joints appeared on the market a decade ago. These joints are more sophisticated and more expensive than mechanical ones. The literature is contradictory regarding changes in gait and balance when using these sophisticated devices. This study employed a crossover design to assess the comparative performance of a passive mechanical knee prosthesis compared to a microprocessor-controlled knee joint in 15 subjects with an above-knee amputation. Objective measurements of gait and balance were obtained. Subjects demonstrated significantly improved gait characteristics after receiving the microprocessor-controlled prosthetic knee joint (p<0.01). Improvements in gait were a transition from a hyperextended knee to a flexed knee during loading response which resulted in a change from an internal knee flexor moment to a knee extensor moment. The participants' balance also improved (p<0.01). All conditions of the Sensory Organization Test (SOT) demonstrated improvements in equilibrium score. The composite score also increased. Transfemoral amputees using a microprocessor-controlled knee have significant improvements in gait and balance.

  16. Video-assisted structured teaching to improve aseptic technique during neuraxial block.

    PubMed

    Friedman, Z; Siddiqui, N; Mahmoud, S; Davies, S

    2013-09-01

    Teaching epidural catheter insertion tends to focus on developing manual dexterity rather than improving aseptic technique which usually remains poor despite increasing experience. The aim of this study was to compare epidural aseptic technique performance, by novice operators after a targeted teaching intervention, with operators taught aseptic technique before the intervention was initiated. Starting July 2008, two groups of second-year anaesthesia residents (pre- and post-teaching intervention) performing their 4-month obstetric anaesthesia rotation in a university affiliated centre were videotaped three to four times while performing epidural procedures. Trained blinded independent examiners reviewed the procedures. The primary outcome was a comparison of aseptic technique performance scores (0-30 points) graded on a scale task-specific checklist. A total of 86 sessions by 29 residents were included in the study analysis. The intraclass correlation coefficient for inter-rater reliability for the aseptic technique was 0.90. The median aseptic technique scores for the rotation period were significantly higher in the post-intervention group [27.58, inter-quartile range (IQR) 22.33-29.50 vs 16.56, IQR 13.33-22.00]. Similar results were demonstrated when scores were analysed for low, moderate, and high levels of experience throughout the rotation. Procedure-specific aseptic technique teaching, aided by video assessment and video demonstration, helped significantly improve aseptic practice by novice trainees. Future studies should consider looking at retention over longer periods of time in more senior residents.

  17. Tethered Swimming for the Evaluation and Prescription of Resistance Training in Young Swimmers.

    PubMed

    Papoti, Marcelo; da Silva, Adelino S R; Kalva-Filho, Carlos Augusto; Araujo, Gustavo Gomes; Santiago, Vanessa; Martins, LuizEduardo Barreto; Cunha, Sérgio Augusto; Gobatto, Claudio Alexandre

    2017-02-01

    The aims of the present study were 1) to evaluate the effects of 11 weeks of a typical free-swimming training program on aerobic and stroke parameters determined in tethered swimming (Study 1; n=13) and 2) to investigate the responses of tethered swimming efforts, in addition to free-swimming sessions, through 7 weeks of training (Study 2; n=21). In both studies, subjects performed a graded exercise test in tethered swimming (GET) to determine anaerobic threshold (AnT), stroke rate at AnT (SR AnT ), peak force at GET (PF GET ) and peak blood lactate ([La-] GET ). Participants also swam 100-, 200- and 400-m lengths to evaluate performance. In Study 2, swimmers were divided into control (i. e., only free-swimming; GC [n=11]) and tethered swimming group (i. e., 50% of the main session; G TS [n=10]). The results of Study 1 demonstrate that AnT, PF GET , [La - ] GET and 200-m performance were improved with free-swimming training. The SR AnT decreased with training. In Study 2, free-swimming performance and most of the graded exercise test parameters were not altered in either group. However, [La-] GET improved only for G TS . These results demonstrate that aerobic parameters obtained in tethered swimming can be used to evaluate free-swimming training responses, and the addition of tethered efforts during training routine improves the lactate production capacity of swimmers. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Can proprioception really be improved by exercises?

    PubMed

    Ashton-Miller, J A; Wojtys, E M; Huston, L J; Fry-Welch, D

    2001-05-01

    There is little question that ankle disc training can improve ankle muscle motor performance in a unipedal balance task, most likely through improved strength and coordination [62] and possibly endurance. How much of the observed improvement in motor performance is due to improved ankle proprioception remains unknown. We have reviewed a number of theoretical ways in which training might improve proprioception for moderately challenging weight-bearing situations such as balancing on one leg. Although the relevant experiments have yet to be performed to test this hypothesis, any improvement would theoretically help to reduce injuries at these moderate levels of challenge. We question, however, whether these exercises can ever improve the reactive response required to prevent injury under the most challenging time-critical situations. If confirmed, this limitation needs to be acknowledged by authors and practitioners alike. Alternative protective strategies for the most challenging time-critical situations should be sought. We conclude that, despite their widespread acceptance, current exercises aimed at "improving proprioception" have not been demonstrated to achieve that goal. We have outlined theoretical scenarios by which proprioception might be improved, but these are speculative. The relevant experiments remain to be conducted. We argue that even if they were proven to improve proprioception, under the best circumstances such exercises could only prevent injury under slow to intermediate rate provocations to the joint musculoligamentous complex in question.

  19. Performance Improvement Through Indexing of Turbine Airfoils. Part 2; Numerical Simulation

    NASA Technical Reports Server (NTRS)

    Griffin, Lisa W.; Huber, Frank W.; Sharma, Om P.

    1996-01-01

    An experimental/analytical study has been conducted to determine the performance improvements achievable by circumferentially indexing succeeding rows of turbine stator airfoils. A series of tests was conducted to experimentally investigate stator wake clocking effects on the performance of the space shuttle main engine (SSME) alternate turbopump development (ATD) fuel turbine test article (TTA). The results from this study indicate that significant increases in stage efficiency can be attained through application of this airfoil clocking concept. Details of the experiment and its results are documented in part 1 of this paper. In order to gain insight into the mechanisms of the performance improvement, extensive computational fluid dynamics (CFD) simulations were executed. The subject of the present paper is the initial results from the CFD investigation of the configurations and conditions detailed in part 1 of the paper. To characterize the aerodynamic environments in the experimental test series, two-dimensional (2D), time accurate, multistage, viscous analyses were performed at the TTA midspan. Computational analyses for five different circumferential positions of the first stage stator have been completed. Details of the computational procedure and the results are presented. The analytical results verify the experimentally demonstrated performance improvement and are compared with data whenever possible. Predictions of time-averaged turbine efficiencies as well as gas conditions throughout the flow field are presented. An initial understanding of the turbine performance improvement mechanism based on the results from this investigation is described.

  20. Improvement of attention with amphetamine in low- and high-performing rats.

    PubMed

    Turner, Karly M; Burne, Thomas H J

    2016-09-01

    Attentional deficits occur in a range of neuropsychiatric disorders, such as schizophrenia and attention deficit hyperactivity disorder. Psychostimulants are one of the main treatments for attentional deficits, yet there are limited reports of procognitive effects of amphetamine in preclinical studies. Therefore, task development may be needed to improve predictive validity when measuring attention in rodents. This study aimed to use a modified signal detection task (SDT) to determine if and at what doses amphetamine could improve attention in rats. Sprague-Dawley rats were trained on the SDT prior to amphetamine challenge (0.1, 0.25, 0.75 and 1.25 mg/kg). This dose range was predicted to enhance and disrupt cognition with the effect differing between individuals depending on baseline performance. Acute low dose amphetamine (0.1 and 0.25 mg/kg) improved accuracy, while the highest dose (1.25 mg/kg) significantly disrupted performance. The effects differed for low- and high-performing groups across these doses. The effect of amphetamine on accuracy was found to significantly correlate with baseline performance in rats. This study demonstrates that improvement in attentional performance with systemic amphetamine is dependent on baseline accuracy in rats. Indicative of the inverted U-shaped relationship between dopamine and cognition, there was a baseline-dependent shift in performance with increasing doses of amphetamine. The SDT may be a useful tool for investigating individual differences in attention and response to psychostimulants in rodents.

  1. Changes in Neural Connectivity and Memory Following a Yoga Intervention for Older Adults: A Pilot Study.

    PubMed

    Eyre, Harris A; Acevedo, Bianca; Yang, Hongyu; Siddarth, Prabha; Van Dyk, Kathleen; Ercoli, Linda; Leaver, Amber M; Cyr, Natalie St; Narr, Katherine; Baune, Bernhard T; Khalsa, Dharma S; Lavretsky, Helen

    2016-01-01

    No study has explored the effect of yoga on cognitive decline and resting-state functional connectivity. This study explored the relationship between performance on memory tests and resting-state functional connectivity before and after a yoga intervention versus active control for subjects with mild cognitive impairment (MCI). Participants ( ≥ 55 y) with MCI were randomized to receive a yoga intervention or active "gold-standard" control (i.e., memory enhancement training (MET)) for 12 weeks. Resting-state functional magnetic resonance imaging was used to map correlations between brain networks and memory performance changes over time. Default mode networks (DMN), language and superior parietal networks were chosen as networks of interest to analyze the association with changes in verbal and visuospatial memory performance. Fourteen yoga and 11 MET participants completed the study. The yoga group demonstrated a statistically significant improvement in depression and visuospatial memory. We observed improved verbal memory performance correlated with increased connectivity between the DMN and frontal medial cortex, pregenual anterior cingulate cortex, right middle frontal cortex, posterior cingulate cortex, and left lateral occipital cortex. Improved verbal memory performance positively correlated with increased connectivity between the language processing network and the left inferior frontal gyrus. Improved visuospatial memory performance correlated inversely with connectivity between the superior parietal network and the medial parietal cortex. Yoga may be as effective as MET in improving functional connectivity in relation to verbal memory performance. These findings should be confirmed in larger prospective studies.

  2. Quality of Care for PTSD and Depression in the Military Health System

    DTIC Science & Technology

    evaluate the receipt of recommended assessments and treatments. These measures draw on multiple data sources including administrative encounter data...services are effective in reducing symptoms. When comparing performance between 20122013 and 20132014, most measures demonstrated slight improvement ...in 20132014 for over 38,000 active-component service members with PTSD or depression. The assessment includes performance on 30 quality measures to

  3. Life Cycle Costing: A Working Level Approach

    DTIC Science & Technology

    1981-06-01

    Effects Analysis ( FMEA ) ...... ................ .. 59 Logistics Performance Factors (LPFs) 60 Planning the Use of Life Cycle Cost in the Demonstration...form. Failure Mode and Effects Analysis ( FMEA ). Description. FMEA is a technique that attempts to improve the design of any particular unit. The FMEA ...failure modes and also eliminate extra parts or ones that are used to achieve more performance than is necessary (16:5-14]. Advantages. FMEA forces

  4. Evaluating the Effect of Virtual Reality Temporal Bone Simulation on Mastoidectomy Performance: A Meta-analysis.

    PubMed

    Lui, Justin T; Hoy, Monica Y

    2017-06-01

    Background The increasing prevalence of virtual reality simulation in temporal bone surgery warrants an investigation to assess training effectiveness. Objectives To determine if temporal bone simulator use improves mastoidectomy performance. Data Sources Ovid Medline, Embase, and PubMed databases were systematically searched per the PRISMA guidelines. Review Methods Inclusion criteria were peer-reviewed publications that utilized quantitative data of mastoidectomy performance following the use of a temporal bone simulator. The search was restricted to human studies published in English. Studies were excluded if they were in non-peer-reviewed format, were descriptive in nature, or failed to provide surgical performance outcomes. Meta-analysis calculations were then performed. Results A meta-analysis based on the random-effects model revealed an improvement in overall mastoidectomy performance following training on the temporal bone simulator. A standardized mean difference of 0.87 (95% CI, 0.38-1.35) was generated in the setting of a heterogeneous study population ( I 2 = 64.3%, P < .006). Conclusion In the context of a diverse population of virtual reality simulation temporal bone surgery studies, meta-analysis calculations demonstrate an improvement in trainee mastoidectomy performance with virtual simulation training.

  5. Sleep and Athletic Performance.

    PubMed

    Watson, Andrew M

    Sleep is an essential component of health and well-being, with significant impacts on physical development, emotional regulation, cognitive performance, and quality of life. Along with being an integral part of the recovery and adaptive process between bouts of exercise, accumulating evidence suggests that increased sleep duration and improved sleep quality in athletes are associated with improved performance and competitive success. In addition, better sleep may reduce the risk of both injury and illness in athletes, not only optimizing health but also potentially enhancing performance through increased participation in training. Despite this, most studies have found that athletes fail to obtain the recommended amount of sleep, threatening both performance and health. Athletes face a number of obstacles that can reduce the likelihood of obtaining proper sleep, such as training and competition schedules, travel, stress, academic demands, and overtraining. In addition, athletes have been found to demonstrate poor self-assessment of their sleep duration and quality. In light of this, athletes may require more careful monitoring and intervention to identify individuals at risk and promote proper sleep to improve both performance and overall health. This review attempts to highlight the recent literature regarding sleep issues in athletes, the effects of sleep on athletic performance, and interventions to enhance proper sleep in athletes.

  6. Optimized Li-Ion Electrolytes Containing Fluorinated Ester Co-Solvents

    NASA Technical Reports Server (NTRS)

    Prakash, G. K. Surya; Smart, Marshall; Smith, Kiah; Bugga, Ratnakumar

    2010-01-01

    A number of experimental lithium-ion cells, consisting of MCMB (meso-carbon microbeads) carbon anodes and LiNi(0.8)Co(0.2)O2 cathodes, have been fabricated with increased safety and expanded capability. These cells serve to verify and demonstrate the reversibility, low-temperature performance, and electrochemical aspects of each electrode as determined from a number of electrochemical characterization techniques. A number of Li-ion electrolytes possessing fluorinated ester co-solvents, namely trifluoroethyl butyrate (TFEB) and trifluoroethyl propionate (TFEP), were demonstrated to deliver good performance over a wide temperature range in experimental lithium-ion cells. The general approach taken in the development of these electrolyte formulations is to optimize the type and composition of the co-solvents in ternary and quaternary solutions, focusing upon adequate stability [i.e., EC (ethylene carbonate) content needed for anode passivation, and EMC (ethyl methyl carbonate) content needed for lowering the viscosity and widening the temperature range, while still providing good stability], enhancing the inherent safety characteristics (incorporation of fluorinated esters), and widening the temperature range of operation (the use of both fluorinated and non-fluorinated esters). Further - more, the use of electrolyte additives, such as VC (vinylene carbonate) [solid electrolyte interface (SEI) promoter] and DMAc (thermal stabilizing additive), provide enhanced high-temperature life characteristics. Multi-component electrolyte formulations enhance performance over a temperature range of -60 to +60 C. With the need for more safety with the use of these batteries, flammability was a consideration. One of the solvents investigated, TFEB, had the best performance with improved low-temperature capability and high-temperature resilience. This work optimized the use of TFEB as a co-solvent by developing the multi-component electrolytes, which also contain non-halogenated esters, film forming additives, thermal stabilizing additives, and flame retardant additives. Further optimization of these electrolyte formulations is anticipated to yield improved performance. It is also anticipated that much improved performance will be demonstrated once these electrolyte solutions are incorporated into hermetically sealed, large capacity prototype cells, especially if effort is devoted to ensure that all electrolyte components are highly pure.

  7. The more the merrier? Increasing group size may be detrimental to decision-making performance in nominal groups.

    PubMed

    Amir, Ofra; Amir, Dor; Shahar, Yuval; Hart, Yuval; Gal, Kobi

    2018-01-01

    Demonstrability-the extent to which group members can recognize a correct solution to a problem-has a significant effect on group performance. However, the interplay between group size, demonstrability and performance is not well understood. This paper addresses these gaps by studying the joint effect of two factors-the difficulty of solving a problem and the difficulty of verifying the correctness of a solution-on the ability of groups of varying sizes to converge to correct solutions. Our empirical investigations use problem instances from different computational complexity classes, NP-Complete (NPC) and PSPACE-complete (PSC), that exhibit similar solution difficulty but differ in verification difficulty. Our study focuses on nominal groups to isolate the effect of problem complexity on performance. We show that NPC problems have higher demonstrability than PSC problems: participants were significantly more likely to recognize correct and incorrect solutions for NPC problems than for PSC problems. We further show that increasing the group size can actually decrease group performance for some problems of low demonstrability. We analytically derive the boundary that distinguishes these problems from others for which group performance monotonically improves with group size. These findings increase our understanding of the mechanisms that underlie group problem-solving processes, and can inform the design of systems and processes that would better facilitate collective decision-making.

  8. Using a physics experiment in a lecture setting to engage biology students with the concepts of Poiseuille's law.

    PubMed

    Breckler, Jennifer L; Christensen, Tina; Sun, Wendy

    2013-06-01

    Biology students enrolled in a typical undergraduate physiology course encounter Poiseuille's law, a physics equation that describes the properties governing the flow of blood through the circulation. According to the equation, a small change in vessel radius has an exponential effect on resistance, resulting in a larger than expected change in blood flow. To help engage students in this important concept, we performed a physics experiment as a lecture demonstration to mimic the original research by the 19th-century French scientist. We tested its impact as a research project and found that students who viewed the demonstration reacted very positively and showed an immediate increase in test performance, while the control group was able to independently "catch up" at the fourth week posttest. We further examined whether students' math skills mapped to learning gains. The students with lower math scores who viewed the demonstration had slightly more improvement in test performance than those students who did not view the demonstration. Our data suggest that watching a lecture demonstration may be of even greater benefit to biology students with lower math achievement.

  9. Using a Physics Experiment in a Lecture Setting to Engage Biology Students with the Concepts of Poiseuille's Law

    PubMed Central

    Breckler, Jennifer L.; Christensen, Tina; Sun, Wendy

    2013-01-01

    Biology students enrolled in a typical undergraduate physiology course encounter Poiseuille's law, a physics equation that describes the properties governing the flow of blood through the circulation. According to the equation, a small change in vessel radius has an exponential effect on resistance, resulting in a larger than expected change in blood flow. To help engage students in this important concept, we performed a physics experiment as a lecture demonstration to mimic the original research by the 19th-century French scientist. We tested its impact as a research project and found that students who viewed the demonstration reacted very positively and showed an immediate increase in test performance, while the control group was able to independently “catch up” at the fourth week posttest. We further examined whether students’ math skills mapped to learning gains. The students with lower math scores who viewed the demonstration had slightly more improvement in test performance than those students who did not view the demonstration. Our data suggest that watching a lecture demonstration may be of even greater benefit to biology students with lower math achievement. PMID:23737633

  10. A pilot study of biomechanical assessment before and after an integrative training program for adolescents with juvenile fibromyalgia.

    PubMed

    Tran, Susan T; Thomas, Staci; DiCesare, Christopher; Pfeiffer, Megan; Sil, Soumitri; Ting, Tracy V; Williams, Sara E; Myer, Gregory D; Kashikar-Zuck, Susmita

    2016-07-22

    Adolescents with juvenile fibromyalgia (JFM) tend to be very sedentary and avoid participation in physical activity. A prior study suggested that JFM patients show altered biomechanics compared to healthy adolescents which may make them more prone to pain/injury during exercise. A new intervention combining well established cognitive behavioral therapy (CBT) techniques with specialized neuromuscular exercise -Fibromyalgia Integrative Training for Teens (FIT Teens) was developed and shown to be promising in improving functioning in adolescents with JFM. In contrast to traditional exercise programs such as aerobic or resistance training, neuromuscular training is a tailored approach which targets gait, posture, balance and movement mechanics which form the foundation for safe exercise participation with reduced risk for injury or pain (and hence more tolerable by JFM patients). The aim of this pilot feasibility study was to establish whether objective biomechanical assessment including sophisticated 3-D motion analysis would be useful in measuring improvements in strength, balance, gait, and functional performance after participation in the 8-week FIT Teens program. Eleven female participants with JFM (ages 12-18 years) completed pre- and post-treatment assessments of biomechanics, including walking gait analysis, lower extremity strength assessment, functional performance, and dynamic postural stability. Descriptive data indicated that mechanics of walking gait and functional performance appeared to improve after treatment. Hip abduction strength and dynamic postural control also demonstrated improvements bilaterally. Overall, the results of this pilot study offer initial evidence for the utility of biomechanical assessment to objectively demonstrate observable changes in biomechanical performance after an integrated training intervention for youth with JFM. If replicated in larger controlled studies, findings would suggest that through the FIT Teens intervention, adolescents with JFM can progress towards normalized strength and biomechanics, which may enhance their ability to engage in physical exercise.

  11. Visuomotor learning in cerebellar patients.

    PubMed

    Timmann, D; Shimansky, Y; Larson, P S; Wunderlich, D A; Stelmach, G E; Bloedel, J R

    1996-11-01

    The aim of the present study was to demonstrate that patients with pathology affecting substantial regions of the cerebellum can improve their performance in a series of two-dimensional tracing tasks, thus supporting the view that this type of motor behavior can be acquired even when the integrity of this structure is compromised. Eight patients with chronic, isolated cerebellar lesions and eight age- and sex-matched healthy controls were tested. Three patients had mild, five had moderate upper limb ataxia. The experiment was divided into two parts. In the first, subjects traced an irregularly shaped outline over 20 consecutive trials ('Trace 1' task). Next, subjects were asked to redraw the object without any underlying template as a guide ('Memory 1' task). In the second part of the study, subjects were asked to trace a different, irregularly shaped outline over 20 consecutive trials ('Trace 2' task). Next, they were required to redraw it by memory with its axis rotated 90 degrees ('Memory 2' task). In each of the memory tasks the template was placed over the drawn image after each trial and shown to the subjects. The error of performance was determined by calculating three different measurements, each focused on different aspects of the task. Based on these measurements, the cerebellar patients showed improvement in both memory tasks. In the 'Memory 1' task the calculated error decreased significantly for the patients with mild ataxia. In the 'Memory 2' task all cerebellar patients improved their performance substantially enough to reduce significantly the magnitude of all three error measurements. The experiments demonstrate that patients with cerebellar lesions are capable of improving substantially their performance of a complex motor task involving the recall of memorized shapes and the visuomotor control of a tracing movement.

  12. Control system design for flexible structures using data models

    NASA Technical Reports Server (NTRS)

    Irwin, R. Dennis; Frazier, W. Garth; Mitchell, Jerrel R.; Medina, Enrique A.; Bukley, Angelia P.

    1993-01-01

    The dynamics and control of flexible aerospace structures exercises many of the engineering disciplines. In recent years there has been considerable research in the developing and tailoring of control system design techniques for these structures. This problem involves designing a control system for a multi-input, multi-output (MIMO) system that satisfies various performance criteria, such as vibration suppression, disturbance and noise rejection, attitude control and slewing control. Considerable progress has been made and demonstrated in control system design techniques for these structures. The key to designing control systems for these structures that meet stringent performance requirements is an accurate model. It has become apparent that theoretically and finite-element generated models do not provide the needed accuracy; almost all successful demonstrations of control system design techniques have involved using test results for fine-tuning a model or for extracting a model using system ID techniques. This paper describes past and ongoing efforts at Ohio University and NASA MSFC to design controllers using 'data models.' The basic philosophy of this approach is to start with a stabilizing controller and frequency response data that describes the plant; then, iteratively vary the free parameters of the controller so that performance measures become closer to satisfying design specifications. The frequency response data can be either experimentally derived or analytically derived. One 'design-with-data' algorithm presented in this paper is called the Compensator Improvement Program (CIP). The current CIP designs controllers for MIMO systems so that classical gain, phase, and attenuation margins are achieved. The center-piece of the CIP algorithm is the constraint improvement technique which is used to calculate a parameter change vector that guarantees an improvement in all unsatisfied, feasible performance metrics from iteration to iteration. The paper also presents a recently demonstrated CIP-type algorithm, called the Model and Data Oriented Computer-Aided Design System (MADCADS), developed for achieving H(sub infinity) type design specifications using data models. Control system design for the NASA/MSFC Single Structure Control Facility are demonstrated for both CIP and MADCADS. Advantages of design-with-data algorithms over techniques that require analytical plant models are also presented.

  13. Preparation and Tribological Study of Biodegradable Lubrication Films on Si Substrate

    PubMed Central

    Shi, Shih-Chen; Huang, Teng-Feng; Wu, Jhen-Yu

    2015-01-01

    A novel method for preparing eco-biodegradable lubricant based on hydroxypropyl methylcellulose (HPMC) via hydration process is demonstrated. The smooth and homogeneous HPMC coating has a uniform thickness (~35 μm). It has been demonstrated that the preparation parameters play a critical role in controlling the lubricating behavior of the coating; in addition, excess HPMC and water concentration suppress the tribology properties. Nevertheless, a remarkable friction-reduction and anti-wear performance has been obtained. Impressively, the preparation parameter of 5% HPMC + 30 mL water significantly improves lubricant performance and durability. A simple approach for the water-degradability evaluation of HPMC is proposed. PMID:28788029

  14. Development of advanced fuel cell system, phase 2

    NASA Technical Reports Server (NTRS)

    Handley, L. M.; Meyer, A. P.; Bell, W. F.

    1973-01-01

    A multiple task research and development program was performed to improve the weight, life, and performance characteristics of hydrogen-oxygen alkaline fuel cells for advanced power systems. Development and characterization of a very stable gold alloy catalyst was continued from Phase I of the program. A polymer material for fabrication of cell structural components was identified and its long term compatibility with the fuel cell environment was demonstrated in cell tests. Full scale partial cell stacks, with advanced design closed cycle evaporative coolers, were tested. The characteristics demonstrated in these tests verified the feasibility of developing the engineering model system concept into an advanced lightweight long life powerplant.

  15. Amorphous/crystalline hybrid MoO2 nanosheets for high-energy lithium-ion capacitors.

    PubMed

    Zhao, Xu; Wang, Hong-En; Cao, Jian; Cai, Wei; Sui, Jiehe

    2017-09-26

    A carbon-free MoO 2 nanosheet with amorphous/crystalline hybrid domain was synthesized, and demonstrated to be an efficient host material for lithium-ion capacitors. Discrepant crystallinity in MoO 2 shows unique boundaries, which can improve Li-ion diffusion through the electrode. Improved rate capacities and cycling stability open the door to design of high-performance lithium ion capacitor bridging batteries and supercapacitors.

  16. Incorporating Early Learning Strategies in the School Improvement Grants (SIG) Program: How Three Schools Integrated Early Childhood Strategies into School Turnaround Efforts to Improve Instruction for All Students

    ERIC Educational Resources Information Center

    Connors-Tadros, Lori; Dunn, Lenay; Martella, Jana; McCauley, Carlas

    2015-01-01

    A significant body of research shows that achievement gaps evident in persistently low-performing schools, in many instances, manifest prior to children entering kindergarten. High-quality early learning programs have proven to demonstrate positive effects on closing academic gaps both for individual children and in the aggregate for the school.…

  17. Performance improvement in PEMFC using aligned carbon nanotubes as electrode catalyst support.

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

    Liu, D. J.; Yang, J.; Kariuki, N.

    2008-01-01

    A novel membrane electrode assembly (MEA) using aligned carbon nanotubes (ACNT) as the electrocatalyst support was developed for proton exchange membrane fuel cell (PEMFC) application. A multiple-step process of preparing ACNT-PEMFC including ACNT layer growth and catalyzing, MEA fabrication, and single cell packaging is reported. Single cell polarization studies demonstrated improved fuel utilization and higher power density in comparison with the conventional, ink based MEA.

  18. Web-Based Predictive Analytics to Improve Patient Flow in the Emergency Department

    NASA Technical Reports Server (NTRS)

    Buckler, David L.

    2012-01-01

    The Emergency Department (ED) simulation project was established to demonstrate how requirements-driven analysis and process simulation can help improve the quality of patient care for the Veterans Health Administration's (VHA) Veterans Affairs Medical Centers (VAMC). This project developed a web-based simulation prototype of patient flow in EDs, validated the performance of the simulation against operational data, and documented IT requirements for the ED simulation.

  19. High dynamic range hyperspectral imaging for camouflage performance test and evaluation

    NASA Astrophysics Data System (ADS)

    Pearce, D.; Feenan, J.

    2016-10-01

    This paper demonstrates the use of high dynamic range processing applied to the specific technique of hyper-spectral imaging with linescan spectrometers. The technique provides an improvement in signal to noise for reflectance estimation. This is demonstrated for field measurements of rural imagery collected from a ground-based linescan spectrometer of rural scenes. Once fully developed, the specific application is expected to improve the colour estimation approaches and consequently the test and evaluation accuracy of camouflage performance tests. Data are presented on both field and laboratory experiments that have been used to evaluate the improvements granted by the adoption of high dynamic range data acquisition in the field of hyperspectral imaging. High dynamic ranging imaging is well suited to the hyperspectral domain due to the large variation in solar irradiance across the visible and short wave infra-red (SWIR) spectrum coupled with the wavelength dependence of the nominal silicon detector response. Under field measurement conditions it is generally impractical to provide artificial illumination; consequently, an adaptation of the hyperspectral imaging and re ectance estimation process has been developed to accommodate the solar spectrum. This is shown to improve the signal to noise ratio for the re ectance estimation process of scene materials in the 400-500 nm and 700-900 nm regions.

  20. Solid-liquid staged combustion space boosters

    NASA Technical Reports Server (NTRS)

    Culver, D. W.

    1990-01-01

    NASA has begun to evaluate solid-liquid hybrid propulsion for launch vehicle booster. A three-phase program was outlined to identify, acquire, and demonstrate technology needed to approximate solid and liquid propulsion state of the art. Aerojet has completed a Phase 1 study and recommends a solid-liquid staged combustion concept in which turbopump fed LO2 is burned with fuel-rich solid propellant effluent in aft-mounted thrust chambers.These reasonably sized thrust chambers are LO2 regeneratively cooled, supplemented with fuel-rich barrier cooling. Turbopumps are driven by the resulting GO2 coolant in an expander-bleed-burnoff cycle. Turbine exhaust pressurizes the LO2 tankage directly, and the excess is bled into supersonic nozzle splitlines, where it combusts with the fuel rich boundary layer. Thrust vector control is enhanced by supersonic nozzle movement on flexseal mounts. Every hybrid solid-liquid concept examined improves booster energy management and launch propellant safety compared to current solid boosters. Solid-liquid staged combustion improves hybrid performance by improving both combustion efficiency and combustion stability, especially important for large boosters. These improvements result from careful fluid management and use of smaller combustors. The study shows NASA safety, reliability, cost, and performance criteria are best met with this concept, wherein simple hardware relies on several separate emerging technologies, all of which have been demonstrated successfully.

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