Real-time Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn D.; Rahman, Zia-Ur; Jobson, Daniel J.; Woodell, Glenn A.; Harrah, Steven D.

2005-01-01

Flying in poor visibility conditions, such as rain, snow, fog or haze, is inherently dangerous. However these conditions can occur at nearly any location, so inevitably pilots must successfully navigate through them. At NASA Langley Research Center (LaRC), under support of the Aviation Safety and Security Program Office and the Systems Engineering Directorate, we are developing an Enhanced Vision System (EVS) that combines image enhancement and synthetic vision elements to assist pilots flying through adverse weather conditions. This system uses a combination of forward-looking infrared and visible sensors for data acquisition. A core function of the system is to enhance and fuse the sensor data in order to increase the information content and quality of the captured imagery. These operations must be performed in real-time for the pilot to use while flying. For image enhancement, we are using the LaRC patented Retinex algorithm since it performs exceptionally well for improving low-contrast range imagery typically seen during poor visibility conditions. In general, real-time operation of the Retinex requires specialized hardware. To date, we have successfully implemented a single-sensor real-time version of the Retinex on several different Digital Signal Processor (DSP) platforms. In this paper we give an overview of the EVS and its performance requirements for real-time enhancement and fusion and we discuss our current real-time Retinex implementations on DSPs.

Real-time enhanced vision system

NASA Astrophysics Data System (ADS)

Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.; Harrah, Steven D.

2005-05-01

Flying in poor visibility conditions, such as rain, snow, fog or haze, is inherently dangerous. However these conditions can occur at nearly any location, so inevitably pilots must successfully navigate through them. At NASA Langley Research Center (LaRC), under support of the Aviation Safety and Security Program Office and the Systems Engineering Directorate, we are developing an Enhanced Vision System (EVS) that combines image enhancement and synthetic vision elements to assist pilots flying through adverse weather conditions. This system uses a combination of forward-looking infrared and visible sensors for data acquisition. A core function of the system is to enhance and fuse the sensor data in order to increase the information content and quality of the captured imagery. These operations must be performed in real-time for the pilot to use while flying. For image enhancement, we are using the LaRC patented Retinex algorithm since it performs exceptionally well for improving low-contrast range imagery typically seen during poor visibility poor visibility conditions. In general, real-time operation of the Retinex requires specialized hardware. To date, we have successfully implemented a single-sensor real-time version of the Retinex on several different Digital Signal Processor (DSP) platforms. In this paper we give an overview of the EVS and its performance requirements for real-time enhancement and fusion and we discuss our current real-time Retinex implementations on DSPs.

Evaluation and Application of Enhancements to the Performance of the ASDE-3 Radar in Heavy Rain

DOT National Transportation Integrated Search

1982-03-01

This report presents the results of a study performed by the Transportation Systems Center (TSC) to evaluate two proposed enhancements to the performance of the ASDE-3 Radar in heavy rain: Adaptive gain and adaptive clutter thresholding, (operating w...

Driver's Enhanced Vision System (DEVS)

DOT National Transportation Integrated Search

1996-12-23

This advisory circular (AC) contains performance standards, specifications, and : recommendations for Drivers Enhanced Vision sSystem (DEVS). The FAA recommends : the use of the guidance in this publication for the design and installation of : DEVS e...

Uniform Gold-Nanoparticle-Decorated {001}-Faceted Anatase TiO2 Nanosheets for Enhanced Solar-Light Photocatalytic Reactions.

PubMed

Shi, Huimin; Zhang, Shi; Zhu, Xupeng; Liu, Yu; Wang, Tao; Jiang, Tian; Zhang, Guanhua; Duan, Huigao

2017-10-25

The {001}-faceted anatase TiO 2 micro-/nanocrystals have been widely investigated for enhancing the photocatalysis and photoelectrochemical performance of TiO 2 nanostructures, but their practical applications still require improved energy conversion efficiency under solar-light and enhanced cycling stability. In this work, we demonstrate the controlled growth of ultrathin {001}-faceted anatase TiO 2 nanosheets on flexible carbon cloth for enhancing the cycling stability, and the solar-light photocatalytic performance of the synthesized TiO 2 nanosheets can be significantly improved by decorating with vapor-phase-deposited uniformly distributed plasmonic gold nanoparticles. The fabricated Au-TiO 2 hybrid system shows an 8-fold solar-light photocatalysis enhancement factor in photodegrading Rhodamine B, a high photocurrent density of 300 μA cm -2 under the illumination of AM 1.5G, and 100% recyclability under a consecutive long-term cycling measurement. Combined with electromagnetic simulations and systematic control experiments, it is believed that the tandem-type separation and transition of plasmon-induced hot electrons from Au nanoparticles to the {001} facet of anatase TiO 2 , and then to the neighboring {101} facet, is responsible for the enhanced solar-light photochemical performance of the hybrid system. The Au-TiO 2 nanosheet system addresses well the problems of the limited solar-light response of anatase TiO 2 and fast recombination of photogenerated electron-hole pairs, representing a promising high-performance recyclable solar-light-responding system for practical photocatalytic reactions.

Cockpit resource management skills enhance combat mission performance in a B-52 simulator

NASA Technical Reports Server (NTRS)

Povenmire, H. Kingsley; Rockway, Marty R.; Bunecke, Joseph L.; Patton, Mark W.

1989-01-01

A cockpit resource management (CRM) program for mission-ready B-52 aircrew is developed. The relationship between CRM performance and combat mission performance is studied. The performances of six crew members flying a simulated high workload mission in a B-52 weapon system trainer are evaluated. The data reveal that CRM performance enhances tactical maneuvers and bombing accuracy.

Online performance evaluation of RAID 5 using CPU utilization

NASA Astrophysics Data System (ADS)

Jin, Hai; Yang, Hua; Zhang, Jiangling

1998-09-01

Redundant arrays of independent disks (RAID) technology is the efficient way to solve the bottleneck problem between CPU processing ability and I/O subsystem. For the system point of view, the most important metric of on line performance is the utilization of CPU. This paper first employs the way to calculate the CPU utilization of system connected with RAID level 5 using statistic average method. From the simulation results of CPU utilization of system connected with RAID level 5 subsystem can we see that using multiple disks as an array to access data in parallel is the efficient way to enhance the on-line performance of disk storage system. USing high-end disk drivers to compose the disk array is the key to enhance the on-line performance of system.

Enhanced Attitude Control Experiment for SSTI Lewis Spacecraft

NASA Technical Reports Server (NTRS)

Maghami, Peoman G.

1997-01-01

The enhanced attitude control system experiment is a technology demonstration experiment on the NASA's small spacecraft technology initiative program's Lewis spacecraft to evaluate advanced attitude control strategies. The purpose of the enhanced attitude control system experiment is to evaluate the feasibility of designing and implementing robust multi-input/multi-output attitude control strategies for enhanced pointing performance of spacecraft to improve the quality of the measurements of the science instruments. Different control design strategies based on modern and robust control theories are being considered for the enhanced attitude control system experiment. This paper describes the experiment as well as the design and synthesis of a mixed H(sub 2)/H(sub infinity) controller for attitude control. The control synthesis uses a nonlinear programming technique to tune the controller parameters and impose robustness and performance constraints. Simulations are carried out to demonstrate the feasibility of the proposed attitude control design strategy. Introduction

Sensor fusion display evaluation using information integration models in enhanced/synthetic vision applications

NASA Technical Reports Server (NTRS)

Foyle, David C.

1993-01-01

Based on existing integration models in the psychological literature, an evaluation framework is developed to assess sensor fusion displays as might be implemented in an enhanced/synthetic vision system. The proposed evaluation framework for evaluating the operator's ability to use such systems is a normative approach: The pilot's performance with the sensor fusion image is compared to models' predictions based on the pilot's performance when viewing the original component sensor images prior to fusion. This allows for the determination as to when a sensor fusion system leads to: poorer performance than one of the original sensor displays, clearly an undesirable system in which the fused sensor system causes some distortion or interference; better performance than with either single sensor system alone, but at a sub-optimal level compared to model predictions; optimal performance compared to model predictions; or, super-optimal performance, which may occur if the operator were able to use some highly diagnostic 'emergent features' in the sensor fusion display, which were unavailable in the original sensor displays.

Acquisition and production of skilled behavior in dynamic decision-making tasks. Semiannual Status Report M.S. Thesis - Georgia Inst. of Tech., Nov. 1992

NASA Technical Reports Server (NTRS)

Kirlik, Alex; Kossack, Merrick Frank

1993-01-01

This status report consists of a thesis entitled 'Ecological Task Analysis: A Method for Display Enhancements.' Previous use of various analysis processes for the purpose of display interface design or enhancement has run the risk of failing to improve user performance due to the analysis resulting in only a sequencial listing of user tasks. Adopting an ecological approach to performing the task analysis, however, may result in the necessary modeling of an unpredictable and variable task domain required to improve user performance. Kirlik has proposed an Ecological Task Analysis framework which is designed for this purpose. It is the purpose of this research to measure this framework's effectiveness at enhancing display interfaces in order to improve user performance. Following the proposed framework, an ecological task analysis of experienced users of a complex and dynamic laboratory task, Star Cruiser, was performed. Based on this analysis, display enhancements were proposed and implemented. An experiment was then conducted to compare this new version of Star Cruiser to the original. By measuring user performance at different tasks, it was determined that during early sessions, use of the enhanced display contributed to better user performance compared to that achieved using the original display. Furthermore, the results indicate that the enhancements proposed as a result of the ecological task analysis affected user performance differently depending on whether they are enhancements which aid in the selection of a possible action or in the performance of an action. Generalizations of these findings to larger, more complex systems were avoided since the analysis was only performed on this one particular system.

Systems and methods for enhancing optical information

DOEpatents

DeVore, Peter Thomas Setsuda; Chou, Jason T.

2018-01-02

An Optical Information Transfer Enhancer System includes a first system for producing an information bearing first optical wave that is impressed with a first information having a first information strength wherein the first optical wave has a first shape. A second system produces a second optical wave. An information strength enhancer module receives the first and said second optical waves and impresses the first optical wave upon the second optical wave via cross-phase modulation (XPM) to produce an information-strength-enhanced second optical wave having a second information strength that is greater than the first information strength of the first optical wave. Following a center-wavelength changer by an Optical Information Transfer Enhancer System improves its performance.

Rapid Slewing of Flexible Space Structures

DTIC Science & Technology

2015-09-01

axis gimbal with elastic joints. The performance of the system can be enhanced by designing antenna maneuvers in which the flexible effects are...the effects of the nonlinearities so the vibrational motion can be constrained for a time-optimal slew. It is shown that by constructing an...joints. The performance of the system can be enhanced by designing antenna maneuvers in which the flexible effects are properly constrained, thus

Enhancements to highway construction scheduling expert system.

DOT National Transportation Integrated Search

2015-05-01

This research was performed to enhance the software tool (Illinois Construction Scheduling Expert : System, ICSES) developed in Phase I of this project (ICT project R27-86) by mining data collected on : IDOT construction projects and differentiating ...

EKF-Based Enhanced Performance Controller Design for Nonlinear Stochastic Systems

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

Zhou, Yuyang; Zhang, Qichun; Wang, Hong

In this paper, a novel control algorithm is presented to enhance the performance of tracking property for a class of non-linear dynamic stochastic systems with unmeasurable variables. To minimize the entropy of tracking errors without changing the existing closed loop with PI controller, the enhanced performance loop is constructed based on the state estimation by extended Kalman Filter and the new controller is designed by full state feedback following this presented control algorithm. Besides, the conditions are obtained for the stability analysis in the mean square sense. In the end, the comparative simulation results are given to illustrate the effectivenessmore » of proposed control algorithm.« less

Hypoglycemia alarm enhancement using data fusion.

PubMed

Skladnev, Victor N; Tarnavskii, Stanislav; McGregor, Thomas; Ghevondian, Nejhdeh; Gourlay, Steve; Jones, Timothy W

2010-01-01

The acceptance of closed-loop blood glucose (BG) control using continuous glucose monitoring systems (CGMS) is likely to improve with enhanced performance of their integral hypoglycemia alarms. This article presents an in silico analysis (based on clinical data) of a modeled CGMS alarm system with trained thresholds on type 1 diabetes mellitus (T1DM) patients that is augmented by sensor fusion from a prototype hypoglycemia alarm system (HypoMon). This prototype alarm system is based on largely independent autonomic nervous system (ANS) response features. Alarm performance was modeled using overnight BG profiles recorded previously on 98 T1DM volunteers. These data included the corresponding ANS response features detected by HypoMon (AiMedics Pty. Ltd.) systems. CGMS data and alarms were simulated by applying a probabilistic model to these overnight BG profiles. The probabilistic model developed used a mean response delay of 7.1 minutes, measurement error offsets on each sample of +/- standard deviation (SD) = 4.5 mg/dl (0.25 mmol/liter), and vertical shifts (calibration offsets) of +/- SD = 19.8 mg/dl (1.1 mmol/liter). Modeling produced 90 to 100 simulated measurements per patient. Alarm systems for all analyses were optimized on a training set of 46 patients and evaluated on the test set of 56 patients. The split between the sets was based on enrollment dates. Optimization was based on detection accuracy but not time to detection for these analyses. The contribution of this form of data fusion to hypoglycemia alarm performance was evaluated by comparing the performance of the trained CGMS and fused data algorithms on the test set under the same evaluation conditions. The simulated addition of HypoMon data produced an improvement in CGMS hypoglycemia alarm performance of 10% at equal specificity. Sensitivity improved from 87% (CGMS as stand-alone measurement) to 97% for the enhanced alarm system. Specificity was maintained constant at 85%. Positive predictive values on the test set improved from 61 to 66% with negative predictive values improving from 96 to 99%. These enhancements were stable within sensitivity analyses. Sensitivity analyses also suggested larger performance increases at lower CGMS alarm performance levels. Autonomic nervous system response features provide complementary information suitable for fusion with CGMS data to enhance nocturnal hypoglycemia alarms. 2010 Diabetes Technology Society.

Space station ECLSS integration analysis: Simplified General Cluster Systems Model, ECLS System Assessment Program enhancements

NASA Technical Reports Server (NTRS)

Ferguson, R. E.

1985-01-01

The data base verification of the ECLS Systems Assessment Program (ESAP) was documented and changes made to enhance the flexibility of the water recovery subsystem simulations are given. All changes which were made to the data base values are described and the software enhancements performed. The refined model documented herein constitutes the submittal of the General Cluster Systems Model. A source listing of the current version of ESAP is provided in Appendix A.

A Hybrid Actuation System Demonstrating Significantly Enhanced Electromechanical Performance

NASA Technical Reports Server (NTRS)

Su, Ji; Xu, Tian-Bing; Zhang, Shujun; Shrout, Thomas R.; Zhang, Qiming

2004-01-01

A hybrid actuation system (HYBAS) utilizing advantages of a combination of electromechanical responses of an electroactive polymer (EAP), an electrostrictive copolymer, and an electroactive ceramic single crystal, PZN-PT single crystal, has been developed. The system employs the contribution of the actuation elements cooperatively and exhibits a significantly enhanced electromechanical performance compared to the performances of the device made of each constituting material, the electroactive polymer or the ceramic single crystal, individually. The theoretical modeling of the performances of the HYBAS is in good agreement with experimental observation. The consistence between the theoretical modeling and experimental test make the design concept an effective route for the development of high performance actuating devices for many applications. The theoretical modeling, fabrication of the HYBAS and the initial experimental results will be presented and discussed.

Optical design applications for enhanced illumination performance

NASA Astrophysics Data System (ADS)

Gilray, Carl; Lewin, Ian

1995-08-01

Nonimaging optical design techniques have been applied in the illumination industry for many years. Recently however, powerful software has been developed which allows accurate simulation and optimization of illumination devices. Wide experience has been obtained in using such design techniques for practical situations. These include automotive lighting where safety is of greatest importance, commercial lighting systems designed for energy efficiency, and numerous specialized applications. This presentation will discuss the performance requirements of a variety of illumination devices. It will further cover design methodology and present a variety of examples of practical applications for enhanced system performance.

Enhanced digital mapping project : final report

DOT National Transportation Integrated Search

2004-11-19

The Enhanced Digital Map Project (EDMap) was a three-year effort launched in April 2001 to develop a range of digital map database enhancements that enable or improve the performance of driver assistance systems currently under development or conside...

Real-time Enhancement, Registration, and Fusion for a Multi-Sensor Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.

2006-01-01

Over the last few years NASA Langley Research Center (LaRC) has been developing an Enhanced Vision System (EVS) to aid pilots while flying in poor visibility conditions. The EVS captures imagery using two infrared video cameras. The cameras are placed in an enclosure that is mounted and flown forward-looking underneath the NASA LaRC ARIES 757 aircraft. The data streams from the cameras are processed in real-time and displayed on monitors on-board the aircraft. With proper processing the camera system can provide better-than- human-observed imagery particularly during poor visibility conditions. However, to obtain this goal requires several different stages of processing including enhancement, registration, and fusion, and specialized processing hardware for real-time performance. We are using a real-time implementation of the Retinex algorithm for image enhancement, affine transformations for registration, and weighted sums to perform fusion. All of the algorithms are executed on a single TI DM642 digital signal processor (DSP) clocked at 720 MHz. The image processing components were added to the EVS system, tested, and demonstrated during flight tests in August and September of 2005. In this paper we briefly discuss the EVS image processing hardware and algorithms. We then discuss implementation issues and show examples of the results obtained during flight tests. Keywords: enhanced vision system, image enhancement, retinex, digital signal processing, sensor fusion

CAREER DEVELOPMENT

EPA Science Inventory

The Baltimore Summit Project on Career Development/PERFORMS Enhancement/360 Evaluations for All has made some progress. We have identified the fact that we cannot change the current Pass/Fail PERFORMS system to a tiered system. The current pass/fail system does not have a mechani...

Throughput of Coded Optical CDMA Systems with AND Detectors

NASA Astrophysics Data System (ADS)

Memon, Kehkashan A.; Umrani, Fahim A.; Umrani, A. W.; Umrani, Naveed A.

2012-09-01

Conventional detection techniques used in optical code-division multiple access (OCDMA) systems are not optimal and result in poor bit error rate performance. This paper analyzes the coded performance of optical CDMA systems with AND detectors for enhanced throughput efficiencies and improved error rate performance. The results show that the use of AND detectors significantly improve the performance of an optical channel.

Enhanced terahertz imaging system performance analysis and design tool for concealed weapon identification

NASA Astrophysics Data System (ADS)

Murrill, Steven R.; Franck, Charmaine C.; Espinola, Richard L.; Petkie, Douglas T.; De Lucia, Frank C.; Jacobs, Eddie L.

2011-11-01

The U.S. Army Research Laboratory (ARL) and the U.S. Army Night Vision and Electronic Sensors Directorate (NVESD) have developed a terahertz-band imaging system performance model/tool for detection and identification of concealed weaponry. The details of the MATLAB-based model which accounts for the effects of all critical sensor and display components, and for the effects of atmospheric attenuation, concealment material attenuation, and active illumination, were reported on at the 2005 SPIE Europe Security & Defence Symposium (Brugge). An advanced version of the base model that accounts for both the dramatic impact that target and background orientation can have on target observability as related to specular and Lambertian reflections captured by an active-illumination-based imaging system, and for the impact of target and background thermal emission, was reported on at the 2007 SPIE Defense and Security Symposium (Orlando). This paper will provide a comprehensive review of an enhanced, user-friendly, Windows-executable, terahertz-band imaging system performance analysis and design tool that now includes additional features such as a MODTRAN-based atmospheric attenuation calculator and advanced system architecture configuration inputs that allow for straightforward performance analysis of active or passive systems based on scanning (single- or line-array detector element(s)) or staring (focal-plane-array detector elements) imaging architectures. This newly enhanced THz imaging system design tool is an extension of the advanced THz imaging system performance model that was developed under the Defense Advanced Research Project Agency's (DARPA) Terahertz Imaging Focal-Plane Technology (TIFT) program. This paper will also provide example system component (active-illumination source and detector) trade-study analyses using the new features of this user-friendly THz imaging system performance analysis and design tool.

Performance optimization of spectral amplitude coding OCDMA system using new enhanced multi diagonal code

NASA Astrophysics Data System (ADS)

Imtiaz, Waqas A.; Ilyas, M.; Khan, Yousaf

2016-11-01

This paper propose a new code to optimize the performance of spectral amplitude coding-optical code division multiple access (SAC-OCDMA) system. The unique two-matrix structure of the proposed enhanced multi diagonal (EMD) code and effective correlation properties, between intended and interfering subscribers, significantly elevates the performance of SAC-OCDMA system by negating multiple access interference (MAI) and associated phase induce intensity noise (PIIN). Performance of SAC-OCDMA system based on the proposed code is thoroughly analyzed for two detection techniques through analytic and simulation analysis by referring to bit error rate (BER), signal to noise ratio (SNR) and eye patterns at the receiving end. It is shown that EMD code while using SDD technique provides high transmission capacity, reduces the receiver complexity, and provides better performance as compared to complementary subtraction detection (CSD) technique. Furthermore, analysis shows that, for a minimum acceptable BER of 10-9 , the proposed system supports 64 subscribers at data rates of up to 2 Gbps for both up-down link transmission.

The development of a performance-enhancing additive for vapor-compression heat pumps

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

Grzyll, L.R.; Scaringe, R.P.; Gottschlich, J.M.

1997-12-31

This paper describes the testing results of a vapor-compression heat pump operating with HFC-134a refrigerant and a performance-enhancing additive. Preliminary bench-top testing of this additive, when added to polyolester (POE) lubricant and HFC-134a refrigerant, showed surprising enhancements to system COP. To further investigate this finding, the authors designed and fabricated a vapor-compression heat pump test stand for the 3--5 ton range. The authors investigated the effect of different concentrations of this additive on various system performance parameters such as cooling capacity, compressor power requirement, pressure ratio, compressor pressure difference, compressor isentropic efficiency, refrigerant flow rate, and heat exchanger performance. Themore » authors investigated various heat source and heat sink conditions to simulate air-conditioning and heat pump operating conditions. To investigate the effect of this additive on compressor lubrication and life, the authors performed compressor life tests (with scroll and reciprocating compressors), and had lubrication wear tests performed with various concentrations of the additive in the POE lubricant.« less

Operator performance-enhancing technologies to improve safety. A US DOT safety initiative for meeting the human-centered systems challenge.

DOT National Transportation Integrated Search

1999-11-01

The program implements DOT Human Factors Coordinating Committee (HFCC) recommendations for a coordinated Departmental Human Factors Research Program to advance the human-centered systems approach for enhancing transportation safety. Human error is a ...

Analysis of Selected Enhancements to the En Route Central Computing Complex

DOT National Transportation Integrated Search

1981-09-01

This report analyzes selected hardware enhancements that could improve the performance of the 9020 computer systems, which are used to provide en route air traffic control services. These enhancements could be implemented quickly, would be relatively...

Enhanced acoustic sensing through wave compression and pressure amplification in anisotropic metamaterials.

PubMed

Chen, Yongyao; Liu, Haijun; Reilly, Michael; Bae, Hyungdae; Yu, Miao

2014-10-15

Acoustic sensors play an important role in many areas, such as homeland security, navigation, communication, health care and industry. However, the fundamental pressure detection limit hinders the performance of current acoustic sensing technologies. Here, through analytical, numerical and experimental studies, we show that anisotropic acoustic metamaterials can be designed to have strong wave compression effect that renders direct amplification of pressure fields in metamaterials. This enables a sensing mechanism that can help overcome the detection limit of conventional acoustic sensing systems. We further demonstrate a metamaterial-enhanced acoustic sensing system that achieves more than 20 dB signal-to-noise enhancement (over an order of magnitude enhancement in detection limit). With this system, weak acoustic pulse signals overwhelmed by the noise are successfully recovered. This work opens up new vistas for the development of metamaterial-based acoustic sensors with improved performance and functionalities that are highly desirable for many applications.

Improving the recognition of fingerprint biometric system using enhanced image fusion

NASA Astrophysics Data System (ADS)

Alsharif, Salim; El-Saba, Aed; Stripathi, Reshma

2010-04-01

Fingerprints recognition systems have been widely used by financial institutions, law enforcement, border control, visa issuing, just to mention few. Biometric identifiers can be counterfeited, but considered more reliable and secure compared to traditional ID cards or personal passwords methods. Fingerprint pattern fusion improves the performance of a fingerprint recognition system in terms of accuracy and security. This paper presents digital enhancement and fusion approaches that improve the biometric of the fingerprint recognition system. It is a two-step approach. In the first step raw fingerprint images are enhanced using high-frequency-emphasis filtering (HFEF). The second step is a simple linear fusion process between the raw images and the HFEF ones. It is shown that the proposed approach increases the verification and identification of the fingerprint biometric recognition system, where any improvement is justified using the correlation performance metrics of the matching algorithm.

Enhancements for a Dynamic Data Warehousing and Mining System for Large-scale HSCB Data

DTIC Science & Technology

2016-05-27

Page | 1 . . . . . . . . . . . . . . . . . . . Intelligent Automation Incorporated Enhancements for a Dynamic Data...301.294.4241, osavas@i-a-i.com) 1 Work Performed within This Reporting Period .................................................... 2 1.1 Top K User and...5 3 Work to be Performed in the Next Reporting Period

First Toronto Conference on Database Users. Systems that Enhance User Performance.

ERIC Educational Resources Information Center

Doszkocs, Tamas E.; Toliver, David

1987-01-01

The first of two papers discusses natural language searching as a user performance enhancement tool, focusing on artificial intelligence applications for information retrieval and problems with natural language processing. The second presents a conceptual framework for further development and future design of front ends to online bibliographic…

Enhanced Vision for All-Weather Operations Under NextGen

NASA Technical Reports Server (NTRS)

Bailey, Randall E.; Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Kramer, Lynda J.; Williams, Steven P.

2010-01-01

Recent research in Synthetic/Enhanced Vision technology is analyzed with respect to existing Category II/III performance and certification guidance. The goal is to start the development of performance-based vision systems technology requirements to support future all-weather operations and the NextGen goal of Equivalent Visual Operations. This work shows that existing criteria to operate in Category III weather and visibility are not directly applicable since, unlike today, the primary reference for maneuvering the airplane is based on what the pilot sees visually through the "vision system." New criteria are consequently needed. Several possible criteria are discussed, but more importantly, the factors associated with landing system performance using automatic and manual landings are delineated.

Visual enhancements in pick-and-place tasks: Human operators controlling a simulated cylindrical manipulator

NASA Technical Reports Server (NTRS)

Kim, Won S.; Tendick, Frank; Stark, Lawrence

1989-01-01

A teleoperation simulator was constructed with vector display system, joysticks, and a simulated cylindrical manipulator, in order to quantitatively evaluate various display conditions. The first of two experiments conducted investigated the effects of perspective parameter variations on human operators' pick-and-place performance, using a monoscopic perspective display. The second experiment involved visual enhancements of the monoscopic perspective display, by adding a grid and reference lines, by comparison with visual enhancements of a stereoscopic display; results indicate that stereoscopy generally permits superior pick-and-place performance, but that monoscopy nevertheless allows equivalent performance when defined with appropriate perspective parameter values and adequate visual enhancements.

Miniature Loop Heat Pipe with Multiple Evaporators for Thermal Control of Small Spacecraft

NASA Technical Reports Server (NTRS)

Ku, Jentung; Ottenstein, Laura; Douglas, Denya; Pauken, Michael; Birur, Gajanana

2005-01-01

This paper presents an advanced miniature heat transport system for thermal control of small spacecraft. The thermal system consists of a loop heat pipe (LHP) with multiple evaporators and multiple deployable radiators for heat transfer, and variable emittance coatings on the radiators for performance enhancement. Thermoelectric coolers are used to control the loop operating temperature. The thermal system combines the functions of variable conductance heat pipes, thermal switches, thermal diodes, and the state-of-the-art LHPs into a single integrated thermal system. It retains all the performance characteristics of state-of-the-art LHPs and offers additional advantages to enhance the functionality, performance, versatility, and reliability of the system. Steady state and transient analytical models have been developed, and scaling criteria have also been established. A breadboard unit has been built for functional testing in laboratory and thermal vacuum environments. Experimental results show excellent performance of the thermal system and correlate very well with theoretical predictions.

Brief non-symbolic, approximate number practice enhances subsequent exact symbolic arithmetic in children

PubMed Central

Spelke, Elizabeth S.

2014-01-01

Recent research reveals a link between individual differences in mathematics achievement and performance on tasks that activate the approximate number system (ANS): a primitive cognitive system shared by diverse animal species and by humans of all ages. Here we used a brief experimental paradigm to test one causal hypothesis suggested by this relationship: activation of the ANS may enhance children's performance of symbolic arithmetic. Over 2 experiments, children who briefly practiced tasks that engaged primitive approximate numerical quantities performed better on subsequent exact, symbolic arithmetic problems than did children given other tasks involving comparison and manipulation of non-numerical magnitudes (brightness and length). The practice effect appeared specific to mathematics, as no differences between groups were observed on a comparable sentence completion task. These results move beyond correlational research and provide evidence that the exercise of non-symbolic numerical processes can enhance children's performance of symbolic mathematics. PMID:24462713

An enhanced MMW and SMMW/THz imaging system performance prediction and analysis tool for concealed weapon detection and pilotage obstacle avoidance

NASA Astrophysics Data System (ADS)

Murrill, Steven R.; Jacobs, Eddie L.; Franck, Charmaine C.; Petkie, Douglas T.; De Lucia, Frank C.

2015-10-01

The U.S. Army Research Laboratory (ARL) has continued to develop and enhance a millimeter-wave (MMW) and submillimeter- wave (SMMW)/terahertz (THz)-band imaging system performance prediction and analysis tool for both the detection and identification of concealed weaponry, and for pilotage obstacle avoidance. The details of the MATLAB-based model which accounts for the effects of all critical sensor and display components, for the effects of atmospheric attenuation, concealment material attenuation, and active illumination, were reported on at the 2005 SPIE Europe Security and Defence Symposium (Brugge). An advanced version of the base model that accounts for both the dramatic impact that target and background orientation can have on target observability as related to specular and Lambertian reflections captured by an active-illumination-based imaging system, and for the impact of target and background thermal emission, was reported on at the 2007 SPIE Defense and Security Symposium (Orlando). Further development of this tool that includes a MODTRAN-based atmospheric attenuation calculator and advanced system architecture configuration inputs that allow for straightforward performance analysis of active or passive systems based on scanning (single- or line-array detector element(s)) or staring (focal-plane-array detector elements) imaging architectures was reported on at the 2011 SPIE Europe Security and Defence Symposium (Prague). This paper provides a comprehensive review of a newly enhanced MMW and SMMW/THz imaging system analysis and design tool that now includes an improved noise sub-model for more accurate and reliable performance predictions, the capability to account for postcapture image contrast enhancement, and the capability to account for concealment material backscatter with active-illumination- based systems. Present plans for additional expansion of the model's predictive capabilities are also outlined.

The Most Important Languages Today.

ERIC Educational Resources Information Center

Graduating Engineer, 1985

1985-01-01

Lists and describes seven languages (COBOL, FORTRAN, BASIC, PASCAL, C, ADA, and LISP), pointing out that familiarity with one or more will enhance employability. Also lists and describes four operating systems (MSDOS, UNIX, MVS, and VAXX/VMS), indicating that knowledge of these systems will further enhance employability or on-the-job performance.…

Enhancing Student Performance in First-Semester General Chemistry Using Active Feedback through the World Wide Web

ERIC Educational Resources Information Center

Chambers, Kent A.; Blake, Bob

2007-01-01

The World Wide Web recently launched a new interactive feedback system for the instructors, so that can better understanding about their students and their problems. The feedback, in combination with tailored lectures is expected to enhance student performance in the first semester of general chemistry.

Optimal Battery Sizing in Photovoltaic Based Distributed Generation Using Enhanced Opposition-Based Firefly Algorithm for Voltage Rise Mitigation

PubMed Central

Wong, Ling Ai; Shareef, Hussain; Mohamed, Azah; Ibrahim, Ahmad Asrul

2014-01-01

This paper presents the application of enhanced opposition-based firefly algorithm in obtaining the optimal battery energy storage systems (BESS) sizing in photovoltaic generation integrated radial distribution network in order to mitigate the voltage rise problem. Initially, the performance of the original firefly algorithm is enhanced by utilizing the opposition-based learning and introducing inertia weight. After evaluating the performance of the enhanced opposition-based firefly algorithm (EOFA) with fifteen benchmark functions, it is then adopted to determine the optimal size for BESS. Two optimization processes are conducted where the first optimization aims to obtain the optimal battery output power on hourly basis and the second optimization aims to obtain the optimal BESS capacity by considering the state of charge constraint of BESS. The effectiveness of the proposed method is validated by applying the algorithm to the 69-bus distribution system and by comparing the performance of EOFA with conventional firefly algorithm and gravitational search algorithm. Results show that EOFA has the best performance comparatively in terms of mitigating the voltage rise problem. PMID:25054184

Optimal battery sizing in photovoltaic based distributed generation using enhanced opposition-based firefly algorithm for voltage rise mitigation.

PubMed

Wong, Ling Ai; Shareef, Hussain; Mohamed, Azah; Ibrahim, Ahmad Asrul

2014-01-01

This paper presents the application of enhanced opposition-based firefly algorithm in obtaining the optimal battery energy storage systems (BESS) sizing in photovoltaic generation integrated radial distribution network in order to mitigate the voltage rise problem. Initially, the performance of the original firefly algorithm is enhanced by utilizing the opposition-based learning and introducing inertia weight. After evaluating the performance of the enhanced opposition-based firefly algorithm (EOFA) with fifteen benchmark functions, it is then adopted to determine the optimal size for BESS. Two optimization processes are conducted where the first optimization aims to obtain the optimal battery output power on hourly basis and the second optimization aims to obtain the optimal BESS capacity by considering the state of charge constraint of BESS. The effectiveness of the proposed method is validated by applying the algorithm to the 69-bus distribution system and by comparing the performance of EOFA with conventional firefly algorithm and gravitational search algorithm. Results show that EOFA has the best performance comparatively in terms of mitigating the voltage rise problem.

Integration of Mobile AR Technology in Performance Assessment

ERIC Educational Resources Information Center

Kuo-Hung, Chao; Kuo-En, Chang; Chung-Hsien, Lan; Kinshuk; Yao-Ting, Sung

2016-01-01

This study was aimed at exploring how to use augmented reality (AR) technology to enhance the effect of performance assessment (PA). A mobile AR performance assessment system (MARPAS) was developed by integrating AR technology to reduce the limitations in observation and assessment during PA. This system includes three modules: Authentication, AR…

Aircraft Engine-Monitoring System And Display

NASA Technical Reports Server (NTRS)

Abbott, Terence S.; Person, Lee H., Jr.

1992-01-01

Proposed Engine Health Monitoring System and Display (EHMSD) provides enhanced means for pilot to control and monitor performances of engines. Processes raw sensor data into information meaningful to pilot. Provides graphical information about performance capabilities, current performance, and operational conditions in components or subsystems of engines. Provides means to control engine thrust directly and innovative means to monitor performance of engine system rapidly and reliably. Features reduce pilot workload and increase operational safety.

Implementation of Enhanced Propulsion Control Modes for Emergency Flight Operation

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.; Chin, Jeffrey C.; May, Ryan D.; Litt, Jonathan S.; Guo, Ten-Huei

2011-01-01

Aircraft engines can be effective actuators to help pilots avert or recover from emergency situations. Emergency control modes are being developed to enhance the engines performance to increase the probability of recovery under these circumstances. This paper discusses a proposed implementation of an architecture that requests emergency propulsion control modes, allowing the engines to deliver additional performance in emergency situations while still ensuring a specified safety level. In order to determine the appropriate level of engine performance enhancement, information regarding the current emergency scenario (including severity) and current engine health must be known. This enables the engine to operate beyond its nominal range while minimizing overall risk to the aircraft. In this architecture, the flight controller is responsible for determining the severity of the event and the level of engine risk that is acceptable, while the engine controller is responsible for delivering the desired performance within the specified risk range. A control mode selector specifies an appropriate situation-specific enhanced mode, which the engine controller then implements. The enhanced control modes described in this paper provide additional engine thrust or response capabilities through the modification of gains, limits, and the control algorithm, but increase the risk of engine failure. The modifications made to the engine controller to enable the use of the enhanced control modes are described, as are the interaction between the various subsystems and importantly, the interaction between the flight controller/pilot and the propulsion control system. Simulation results demonstrate how the system responds to requests for enhanced operation and the corresponding increase in performance.

Characteristics and Echogenicity of Clinical Ultrasound Contrast Agents: An In Vitro and In Vivo Comparison Study.

PubMed

Hyvelin, Jean-Marc; Gaud, Emmanuel; Costa, Maria; Helbert, Alexandre; Bussat, Philippe; Bettinger, Thierry; Frinking, Peter

2017-05-01

To compare physicochemical characteristics and in vitro and in vivo contrast-enhanced ultrasound imaging performance of 3 commercially available ultrasound contrast agents: SonoVue (Bracco Imaging SpA, Colleretto Giacosa, Italy; also marketed as Lumason in the USA), Definity (Lantheus Medical Imaging, North Billerica, MA) and Optison (GE Healthcare AS, Oslo, Norway). Physicochemical characteristics were measured with a Multisizer Coulter Counter (Beckman Coulter, Fullerton, CA). Two ultrasound systems (Aplio 500; Toshiba Medical Systems Corp, Tochigi-ken, Japan; and Logiq E9; GE Healthcare, Little Chalfont, England) were used with different transducers. Contrast enhancement was measured in vitro by dose-ranging measurements using a custom-built beaker setup; in vivo imaging performances were compared in pigs (heart and liver) and rabbits (liver). Quantitative analyses were performed with VueBox quantification software (Bracco Suisse SA, Plan-les-Ouates, Switzerland). Measured physicochemical characteristics were in agreement with those provided by the manufacturers. In vitro data demonstrated that the performance of SonoVue was similar to or better than that of Definity but superior to Optison (normalized scattered power 2- to 10-fold higher with SonoVue). Similar results were obtained in vivo, although the duration of enhancement in the pig heart was longer for SonoVue compared to Definity, and quantitative analysis revealed higher enhancement for SonoVue (1.5-fold increase). For liver imaging, SonoVue and Definity showed similar contrast enhancement and duration of enhancement, but compared to Optison, both peak enhancement and duration of enhancement were superior for SonoVue (up to 2-fold increase). Imaging performance of SonoVue was similar to or slightly better than that of Definity, but it was superior to Optison for the conditions used in this study. © 2017 by the American Institute of Ultrasound in Medicine.

Computer-Mediated Training Tools to Enhance Joint Task Force Cognitive Leadership Skills

DTIC Science & Technology

2007-04-01

University); and 5d. TASK NUMBER Barclay Lewis (American Systems) 5e. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ...ple G am ing Platform D ecisive A ction for Training ..................................................... 43 6. Perform ance M etrics...Figure 15: Automated Performance Measurement System ................................................................... 48 iv COMPUTER-MEDIATED TRAINING

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).

Phase-shifting point diffraction interferometer focus-aid enhanced mask

DOEpatents

Naulleau, Patrick

2000-01-01

A phase-shifting point diffraction interferometer system (PS/PDI) employing a PS/PDI mask that includes a PDI focus aid is provided. The PDI focus aid mask includes a large or secondary reference pinhole that is slightly displaced from the true or primary reference pinhole. The secondary pinhole provides a larger capture tolerance for interferometrically performing fine focus. With the focus-aid enhanced mask, conventional methods such as the knife-edge test can be used to perform an initial (or rough) focus and the secondary (large) pinhole is used to perform interferometric fine focus. Once the system is well focused, high accuracy interferometry can be performed using the primary (small) pinhole.

Brief report: the relationship between visual acuity, the embedded figures test and systemizing in autism spectrum disorders.

PubMed

Brosnan, Mark J; Gwilliam, Lucy R; Walker, Ian

2012-11-01

Enhanced performance upon the Embedded Figures Test (EFT) in individuals with autism spectrum disorder (ASD) has informed psychological theories of the non-social aspects that characterise ASD. The Extreme Male Brain theory of autism proposes that enhanced visual acuity underpins greater attention to detail (assessed by the EFT) which is a prerequisite for Systemizing. To date, however, no study has empirically examined these relationships. 13 males with ASD and 13 male controls were assessed upon tasks argued to reflect these levels of processing. The ASD group were found to have significantly greater visual acuity, EFT performance and Systemizing ability than the control group. However, regression analysis revealed that the strongest relationship was between visual acuity and EFT performance.

Enhancement mechanisms of short-time aerobic digestion for waste activated sludge in the presence of cocoamidopropyl betaine.

PubMed

Xia, Siqing; Zhou, Yun; Eustance, Everett; Zhang, Zhiqiang

2017-10-18

Cocoamidopropyl betaine (CAPB), which is a biodegradable ampholytic surfactant, has recently been found to dramatically enhance the aerobic digestion of waste activated sludge (WAS) in short-time aerobic digestion (STAD) systems. Therefore, it is important to understand the mechanisms in which CAPB enhances WAS aerobic digestion performance. Results showed that CAPB could dramatically enhance the solubilization of soluble proteins (PN), polysaccharides (PS), nucleic acids (NA) and humic-like substances (HS) in the STAD system within the initial 2 h. Then PN, PS and NA gradually decreased, while HS showed only minor decease. In addition, CAPB increased the proportion of low MW fractions (<20 kDa) from 4.22% to 39.4%, which are more biodegradable. Specific oxygen uptake rates and dehydrogenase enzyme activity results indicated that CAPB markedly improved the aerobic microorganism activities. Microbial community analyses and principle coordinate analyses (PCoA) revealed that CAPB increased the proportion of some functional microorganisms, including Proteobacteria, Planctomycetales, Acinetobacter, Pseudomonas and Aeromonas. The changes driven by CAPB could explain the enhanced performance of the STAD system for WAS aerobic treatment.

Acceptability of quality reporting and pay for performance among primary health centers in Lebanon.

PubMed

Saleh, Shadi S; Alameddine, Mohamad S; Natafgi, Nabil M

2013-01-01

Primary health care (PHC) is emphasized as the cornerstone of any health care system. Enhancing PHC performance is considered a strategy to enhance effective and equitable access to care. This study assesses the acceptability of and factors associated with quality reporting among PHC centers (PHCCs) in Lebanon. The managers of 132 Lebanese Ministry of Health PHCCs were surveyed using a cross-sectional design. Managers' willingness to report quality, participate in comparative quality assessments, and endorse pay-for-performance schemes was evaluated. Collected data were matched to the infrastructural characteristics and services database. Seventy-six percent of managers responded to the questionnaire, 93 percent of whom were willing to report clinical performance. Most expressed strong support for peer-performance comparison and pay-for-performance schemes. Willingness to report was negatively associated with the religious affiliation of centers and presence of health care facilities in the catchment area and favorably associated with use of information systems and the size of population served. The great willingness of PHCC managers to employ quality-enhancing initiatives flags a policy priority for PHC stakeholders to strengthen PHCC infrastructure and to enable reporting in an easy, standardized, and systematic way. Enhancing equity necessitates education and empowerment of managers in remote areas and those managing religiously affiliated centers.

MMW radar enhanced vision systems: the Helicopter Autonomous Landing System (HALS) and Radar-Enhanced Vision System (REVS) are rotary and fixed wing enhanced flight vision systems that enable safe flight operations in degraded visual environments

NASA Astrophysics Data System (ADS)

Cross, Jack; Schneider, John; Cariani, Pete

2013-05-01

Sierra Nevada Corporation (SNC) has developed rotary and fixed wing millimeter wave radar enhanced vision systems. The Helicopter Autonomous Landing System (HALS) is a rotary-wing enhanced vision system that enables multi-ship landing, takeoff, and enroute flight in Degraded Visual Environments (DVE). HALS has been successfully flight tested in a variety of scenarios, from brown-out DVE landings, to enroute flight over mountainous terrain, to wire/cable detection during low-level flight. The Radar Enhanced Vision Systems (REVS) is a fixed-wing Enhanced Flight Vision System (EFVS) undergoing prototype development testing. Both systems are based on a fast-scanning, threedimensional 94 GHz radar that produces real-time terrain and obstacle imagery. The radar imagery is fused with synthetic imagery of the surrounding terrain to form a long-range, wide field-of-view display. A symbology overlay is added to provide aircraft state information and, for HALS, approach and landing command guidance cuing. The combination of see-through imagery and symbology provides the key information a pilot needs to perform safe flight operations in DVE conditions. This paper discusses the HALS and REVS systems and technology, presents imagery, and summarizes the recent flight test results.

FELIN: tailored optronics and systems solutions for dismounted combat

NASA Astrophysics Data System (ADS)

Milcent, A. M.

2009-05-01

The FELIN French modernization program for dismounted combat provides the Armies with info-centric systems which dramatically enhance the performances of the soldier and the platoon. Sagem now has available a portfolio of various equipments, providing C4I, data and voice digital communication, and enhanced vision for day and night operations, through compact high performance electro-optics. The FELIN system provides the infantryman with a high-tech integrated and modular system which increases significantly their detection, recognition, identification capabilities, their situation awareness and information sharing, and this in any dismounted close combat situation. Among the key technologies used in this system, infrared and intensified vision provide a significant improvement in capability, observation performance and protection of the ground soldiers. This paper presents in detail the developed equipments, with an emphasis on lessons learned from the technical and operational feedback from dismounted close combat field tests.

Enhanced pid vs model predictive control applied to bldc motor

NASA Astrophysics Data System (ADS)

Gaya, M. S.; Muhammad, Auwal; Aliyu Abdulkadir, Rabiu; Salim, S. N. S.; Madugu, I. S.; Tijjani, Aminu; Aminu Yusuf, Lukman; Dauda Umar, Ibrahim; Khairi, M. T. M.

2018-01-01

BrushLess Direct Current (BLDC) motor is a multivariable and highly complex nonlinear system. Variation of internal parameter values with environment or reference signal increases the difficulty in controlling the BLDC effectively. Advanced control strategies (like model predictive control) often have to be integrated to satisfy the control desires. Enhancing or proper tuning of a conventional algorithm results in achieving the desired performance. This paper presents a performance comparison of Enhanced PID and Model Predictive Control (MPC) applied to brushless direct current motor. The simulation results demonstrated that the PSO-PID is slightly better than the PID and MPC in tracking the trajectory of the reference signal. The proposed scheme could be useful algorithms for the system.

Enhancements for a Dynamic Data Warehousing and Mining System for Large-Scale Human Social Cultural Behavioral (HSBC) Data

DTIC Science & Technology

2016-09-26

Intelligent Automation Incorporated Enhancements for a Dynamic Data Warehousing and Mining ...Enhancements for a Dynamic Data Warehousing and Mining System for N00014-16-P-3014 Large-Scale Human Social Cultural Behavioral (HSBC) Data 5b. GRANT NUMBER...Representative Media Gallery View. We perform Scraawl’s NER algorithm to the text associated with YouTube post, which classifies the named entities into

Thermophotovoltaic energy generation

DOEpatents

Celanovic, Ivan; Chan, Walker; Bermel, Peter; Yeng, Adrian Y. X.; Marton, Christopher; Ghebrebrhan, Michael; Araghchini, Mohammad; Jensen, Klavs F.; Soljacic, Marin; Joannopoulos, John D.; Johnson, Steven G.; Pilawa-Podgurski, Robert; Fisher, Peter

2015-08-25

Inventive systems and methods for the generation of energy using thermophotovoltaic cells are described. Also described are systems and methods for selectively emitting electromagnetic radiation from an emitter for use in thermophotovoltaic energy generation systems. In at least some of the inventive energy generation systems and methods, a voltage applied to the thermophotovoltaic cell (e.g., to enhance the power produced by the cell) can be adjusted to enhance system performance. Certain embodiments of the systems and methods described herein can be used to generate energy relatively efficiently.

A portable W-band radar system for enhancement of infrared vision in fire fighting operations

NASA Astrophysics Data System (ADS)

Klenner, Mathias; Zech, Christian; Hülsmann, Axel; Kühn, Jutta; Schlechtweg, Michael; Hahmann, Konstantin; Kleiner, Bernhard; Ulrich, Michael; Ambacher, Oliver

2016-10-01

In this paper, we present a millimeter wave radar system which will enhance the performance of infrared cameras used for fire-fighting applications. The radar module is compact and lightweight such that the system can be combined with inertial sensors and integrated in a hand-held infrared camera. This allows for precise distance measurements in harsh environmental conditions, such as tunnel or industrial fires, where optical sensors are unreliable or fail. We discuss the design of the RF front-end, the antenna and a quasi-optical lens for beam shaping as well as signal processing and demonstrate the performance of the system by in situ measurements in a smoke filled environment.

Performance enhancement of optical code-division multiple-access systems using transposed modified Walsh code

NASA Astrophysics Data System (ADS)

Sikder, Somali; Ghosh, Shila

2018-02-01

This paper presents the construction of unipolar transposed modified Walsh code (TMWC) and analysis of its performance in optical code-division multiple-access (OCDMA) systems. Specifically, the signal-to-noise ratio, bit error rate (BER), cardinality, and spectral efficiency were investigated. The theoretical analysis demonstrated that the wavelength-hopping time-spreading system using TMWC was robust against multiple-access interference and more spectrally efficient than systems using other existing OCDMA codes. In particular, the spectral efficiency was calculated to be 1.0370 when TMWC of weight 3 was employed. The BER and eye pattern for the designed TMWC were also successfully obtained using OptiSystem simulation software. The results indicate that the proposed code design is promising for enhancing network capacity.

Analysis of Risk Compensation Behavior on Night Vision Enhancement System

NASA Astrophysics Data System (ADS)

Hiraoka, Toshihiro; Masui, Junya; Nishikawa, Seimei

Advanced driver assistance systems (ADAS) such as a forward obstacle collision warning system (FOCWS) and a night vision enhancement system (NVES) aim to decrease driver's mental workload and enhance vehicle safety by provision of useful information to support driver's perception process and judgment process. On the other hand, the risk homeostasis theory (RHT) cautions that an enhanced safety and a reduced risk would cause a risk compensation behavior such as increasing the vehicle velocity. Therefore, the present paper performed the driving simulator experiments to discuss dependence on the NVES and emergence of the risk compensation behavior. Moreover, we verified the side-effects of spontaneous behavioral adaptation derived from the presentation of the fuel-consumption meter on the risk compensation behavior.

Evaluation of the Physiological Challenges in Extreme Environments: Implications for Enhanced Training, Operational Performance and Sex-Specific Responses

DTIC Science & Technology

2016-10-01

Operational Performance and Sex -Specific Responses PRINCIPAL INVESTIGATOR: Brent C. Ruby CONTRACTING ORGANIZATION: The University of Montana System...Environments: Implications for Enhanced Training, Operational Performance and Sex -Specific Responses 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-2-0075...mitochondrial gene responses were not altered by altitude stress. Moreover, there were no differences across sex . While prior research has clearly

Differentiation of Enhancing Glioma and Primary Central Nervous System Lymphoma by Texture-Based Machine Learning.

PubMed

Alcaide-Leon, P; Dufort, P; Geraldo, A F; Alshafai, L; Maralani, P J; Spears, J; Bharatha, A

2017-06-01

Accurate preoperative differentiation of primary central nervous system lymphoma and enhancing glioma is essential to avoid unnecessary neurosurgical resection in patients with primary central nervous system lymphoma. The purpose of the study was to evaluate the diagnostic performance of a machine-learning algorithm by using texture analysis of contrast-enhanced T1-weighted images for differentiation of primary central nervous system lymphoma and enhancing glioma. Seventy-one adult patients with enhancing gliomas and 35 adult patients with primary central nervous system lymphomas were included. The tumors were manually contoured on contrast-enhanced T1WI, and the resulting volumes of interest were mined for textural features and subjected to a support vector machine-based machine-learning protocol. Three readers classified the tumors independently on contrast-enhanced T1WI. Areas under the receiver operating characteristic curves were estimated for each reader and for the support vector machine classifier. A noninferiority test for diagnostic accuracy based on paired areas under the receiver operating characteristic curve was performed with a noninferiority margin of 0.15. The mean areas under the receiver operating characteristic curve were 0.877 (95% CI, 0.798-0.955) for the support vector machine classifier; 0.878 (95% CI, 0.807-0.949) for reader 1; 0.899 (95% CI, 0.833-0.966) for reader 2; and 0.845 (95% CI, 0.757-0.933) for reader 3. The mean area under the receiver operating characteristic curve of the support vector machine classifier was significantly noninferior to the mean area under the curve of reader 1 ( P = .021), reader 2 ( P = .035), and reader 3 ( P = .007). Support vector machine classification based on textural features of contrast-enhanced T1WI is noninferior to expert human evaluation in the differentiation of primary central nervous system lymphoma and enhancing glioma. © 2017 by American Journal of Neuroradiology.

A Proposed Study Program for the Enhancement of Performance of Clocks in the DCS Timing system.

DTIC Science & Technology

1982-08-31

INTRODUCTION This technical note presents a proposed program of test and analysis with 𔃾 a goal of using prediction techniques to enhance the...future digital DCS and methods of satisfying them so that the reader will understand: (1) what is needed from this program to enhance the performance...over a number of years, using both simulation and analysis , have recommended that all major nodes of the DCS be referenced to Coordinated Universal Time

A radar data processing and enhancement system

NASA Technical Reports Server (NTRS)

Anderson, K. F.; Wrin, J. W.; James, R.

1986-01-01

This report describes the space position data processing system of the NASA Western Aeronautical Test Range. The system is installed at the Dryden Flight Research Facility of NASA Ames Research Center. This operational radar data system (RADATS) provides simultaneous data processing for multiple data inputs and tracking and antenna pointing outputs while performing real-time monitoring, control, and data enhancement functions. Experience in support of the space shuttle and aeronautical flight research missions is described, as well as the automated calibration and configuration functions of the system.

Iterative channel decoding of FEC-based multiple-description codes.

PubMed

Chang, Seok-Ho; Cosman, Pamela C; Milstein, Laurence B

2012-03-01

Multiple description coding has been receiving attention as a robust transmission framework for multimedia services. This paper studies the iterative decoding of FEC-based multiple description codes. The proposed decoding algorithms take advantage of the error detection capability of Reed-Solomon (RS) erasure codes. The information of correctly decoded RS codewords is exploited to enhance the error correction capability of the Viterbi algorithm at the next iteration of decoding. In the proposed algorithm, an intradescription interleaver is synergistically combined with the iterative decoder. The interleaver does not affect the performance of noniterative decoding but greatly enhances the performance when the system is iteratively decoded. We also address the optimal allocation of RS parity symbols for unequal error protection. For the optimal allocation in iterative decoding, we derive mathematical equations from which the probability distributions of description erasures can be generated in a simple way. The performance of the algorithm is evaluated over an orthogonal frequency-division multiplexing system. The results show that the performance of the multiple description codes is significantly enhanced.

Finite wordlength implementation of a megachannel digital spectrum analyzer

NASA Technical Reports Server (NTRS)

Satorius, E. H.; Grimm, M. J.; Zimmerman, G. A.; Wilck, H. C.

1986-01-01

The results of an extensive system analysis of the megachannel spectrum analyzer currently being developed for use in various applications of the Deep Space Network are presented. The intent of this analysis is to quantify the effects of digital quantization errors on system performance. The results of this analysis provide useful guidelines for choosing various system design parameters to enhance system performance.

Performance assessment of an onboard monitoring system for CMV drivers : a field operational test : research brief.

DOT National Transportation Integrated Search

2016-11-01

The primary goal of an onboard monitoring system (OBMS) is to enhance driver performance and safety. OBMSs are employed with the expectation that feedback provided concurrently (via flashing feedback lights in the vehicle) and cumulatively (via coach...

Aircraft Engine On-Line Diagnostics Through Dual-Channel Sensor Measurements: Development of an Enhanced System

NASA Technical Reports Server (NTRS)

Kobayashi, Takahisa; Simon, Donald L.

2008-01-01

In this paper, an enhanced on-line diagnostic system which utilizes dual-channel sensor measurements is developed for the aircraft engine application. The enhanced system is composed of a nonlinear on-board engine model (NOBEM), the hybrid Kalman filter (HKF) algorithm, and fault detection and isolation (FDI) logic. The NOBEM provides the analytical third channel against which the dual-channel measurements are compared. The NOBEM is further utilized as part of the HKF algorithm which estimates measured engine parameters. Engine parameters obtained from the dual-channel measurements, the NOBEM, and the HKF are compared against each other. When the discrepancy among the signals exceeds a tolerance level, the FDI logic determines the cause of discrepancy. Through this approach, the enhanced system achieves the following objectives: 1) anomaly detection, 2) component fault detection, and 3) sensor fault detection and isolation. The performance of the enhanced system is evaluated in a simulation environment using faults in sensors and components, and it is compared to an existing baseline system.

Real-time Enhancement, Registration, and Fusion for an Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.

2006-01-01

Over the last few years NASA Langley Research Center (LaRC) has been developing an Enhanced Vision System (EVS) to aid pilots while flying in poor visibility conditions. The EVS captures imagery using two infrared video cameras. The cameras are placed in an enclosure that is mounted and flown forward-looking underneath the NASA LaRC ARIES 757 aircraft. The data streams from the cameras are processed in real-time and displayed on monitors on-board the aircraft. With proper processing the camera system can provide better-than-human-observed imagery particularly during poor visibility conditions. However, to obtain this goal requires several different stages of processing including enhancement, registration, and fusion, and specialized processing hardware for real-time performance. We are using a real-time implementation of the Retinex algorithm for image enhancement, affine transformations for registration, and weighted sums to perform fusion. All of the algorithms are executed on a single TI DM642 digital signal processor (DSP) clocked at 720 MHz. The image processing components were added to the EVS system, tested, and demonstrated during flight tests in August and September of 2005. In this paper we briefly discuss the EVS image processing hardware and algorithms. We then discuss implementation issues and show examples of the results obtained during flight tests.

Sensor Networking Testbed with IEEE 1451 Compatibility and Network Performance Monitoring

NASA Technical Reports Server (NTRS)

Gurkan, Deniz; Yuan, X.; Benhaddou, D.; Figueroa, F.; Morris, Jonathan

2007-01-01

Design and implementation of a testbed for testing and verifying IEEE 1451-compatible sensor systems with network performance monitoring is of significant importance. The performance parameters measurement as well as decision support systems implementation will enhance the understanding of sensor systems with plug-and-play capabilities. The paper will present the design aspects for such a testbed environment under development at University of Houston in collaboration with NASA Stennis Space Center - SSST (Smart Sensor System Testbed).

A new rate-dependent model for high-frequency tracking performance enhancement of piezoactuator system

NASA Astrophysics Data System (ADS)

Tian, Lizhi; Xiong, Zhenhua; Wu, Jianhua; Ding, Han

2017-05-01

Feedforward-feedback control is widely used in motion control of piezoactuator systems. Due to the phase lag caused by incomplete dynamics compensation, the performance of the composite controller is greatly limited at high frequency. This paper proposes a new rate-dependent model to improve the high-frequency tracking performance by reducing dynamics compensation error. The rate-dependent model is designed as a function of the input and input variation rate to describe the input-output relationship of the residual system dynamics which mainly performs as phase lag in a wide frequency band. Then the direct inversion of the proposed rate-dependent model is used to compensate the residual system dynamics. Using the proposed rate-dependent model as feedforward term, the open loop performance can be improved significantly at medium-high frequency. Then, combining the with feedback controller, the composite controller can provide enhanced close loop performance from low frequency to high frequency. At the frequency of 1 Hz, the proposed controller presents the same performance as previous methods. However, at the frequency of 900 Hz, the tracking error is reduced to be 30.7% of the decoupled approach.

DDDAS for space applications

NASA Astrophysics Data System (ADS)

Blasch, Erik; Pham, Khanh D.; Shen, Dan; Chen, Genshe

2018-05-01

The dynamic data-driven applications systems (DDDAS) paradigm is meant to inject measurements into the execution model for enhanced systems performance. One area off interest in DDDAS is for space situation awareness (SSA). For SSA, data is collected about the space environment to determine object motions, environments, and model updates. Dynamically coupling between the data and models enhances the capabilities of each system by complementing models with data for system control, execution, and sensor management. The paper overviews some of the recent developments in SSA made possible from DDDAS techniques which are for object detection, resident space object tracking, atmospheric models for enhanced sensing, cyber protection, and information management.

Evaluation of alternative phase change materials for energy storage in solar dynamic applications

NASA Technical Reports Server (NTRS)

Crane, R. A.; Dustin, M. O.

1988-01-01

The performance of fluoride salt and metallic thermal energy storage materials are compared in terms of basic performance as applied to solar dynamic power generation. Specific performance considerations include uniformity of cycle inlet temperature, peak cavity temperature, TES utilization, and system weights. Also investigated were means of enhancing the thermal conductivity of the salts and its effect on the system performance.

Performance assessment in brain-computer interface-based augmentative and alternative communication

PubMed Central

2013-01-01

A large number of incommensurable metrics are currently used to report the performance of brain-computer interfaces (BCI) used for augmentative and alterative communication (AAC). The lack of standard metrics precludes the comparison of different BCI-based AAC systems, hindering rapid growth and development of this technology. This paper presents a review of the metrics that have been used to report performance of BCIs used for AAC from January 2005 to January 2012. We distinguish between Level 1 metrics used to report performance at the output of the BCI Control Module, which translates brain signals into logical control output, and Level 2 metrics at the Selection Enhancement Module, which translates logical control to semantic control. We recommend that: (1) the commensurate metrics Mutual Information or Information Transfer Rate (ITR) be used to report Level 1 BCI performance, as these metrics represent information throughput, which is of interest in BCIs for AAC; 2) the BCI-Utility metric be used to report Level 2 BCI performance, as it is capable of handling all current methods of improving BCI performance; (3) these metrics should be supplemented by information specific to each unique BCI configuration; and (4) studies involving Selection Enhancement Modules should report performance at both Level 1 and Level 2 in the BCI system. Following these recommendations will enable efficient comparison between both BCI Control and Selection Enhancement Modules, accelerating research and development of BCI-based AAC systems. PMID:23680020

Improvements in magnetic bearing performance for flywheel energy storage

NASA Technical Reports Server (NTRS)

Plant, David P.; Anand, Davinder K.; Kirk, James A.; Calomeris, Anthony J.; Romero, Robert L.

1988-01-01

The paper considers the development of a 500-Watt-hour magnetically suspended flywheel stack energy storage system. The work includes hardware testing results from a stack flywheel energy storage system, improvements in the area of noncontacting displacement transducers, and performance enhancements of magnetic bearings. Experimental results show that a stack flywheel energy storage system is feasible technology.

Improving rural emergency medical services (EMS) through transportation system enhancements.

DOT National Transportation Integrated Search

2014-05-01

Improved emergency medical services (EMS) will impact traffic safety and public health in rural : communities. Better planned, designed, and operated roadway networks that connect hospitals with : communities in need will enhance EMS performance. To ...

An effective one-dimensional anisotropic fingerprint enhancement algorithm

NASA Astrophysics Data System (ADS)

Ye, Zhendong; Xie, Mei

2012-01-01

Fingerprint identification is one of the most important biometric technologies. The performance of the minutiae extraction and the speed of the fingerprint verification system rely heavily on the quality of the input fingerprint images, so the enhancement of the low fingerprint is a critical and difficult step in a fingerprint verification system. In this paper we proposed an effective algorithm for fingerprint enhancement. Firstly we use normalization algorithm to reduce the variations in gray level values along ridges and valleys. Then we utilize the structure tensor approach to estimate each pixel of the fingerprint orientations. At last we propose a novel algorithm which combines the advantages of onedimensional Gabor filtering method and anisotropic method to enhance the fingerprint in recoverable region. The proposed algorithm has been evaluated on the database of Fingerprint Verification Competition 2004, and the results show that our algorithm performs within less time.

An effective one-dimensional anisotropic fingerprint enhancement algorithm

NASA Astrophysics Data System (ADS)

Ye, Zhendong; Xie, Mei

2011-12-01

Fingerprint identification is one of the most important biometric technologies. The performance of the minutiae extraction and the speed of the fingerprint verification system rely heavily on the quality of the input fingerprint images, so the enhancement of the low fingerprint is a critical and difficult step in a fingerprint verification system. In this paper we proposed an effective algorithm for fingerprint enhancement. Firstly we use normalization algorithm to reduce the variations in gray level values along ridges and valleys. Then we utilize the structure tensor approach to estimate each pixel of the fingerprint orientations. At last we propose a novel algorithm which combines the advantages of onedimensional Gabor filtering method and anisotropic method to enhance the fingerprint in recoverable region. The proposed algorithm has been evaluated on the database of Fingerprint Verification Competition 2004, and the results show that our algorithm performs within less time.

Resolution enhancement using simultaneous couple illumination

NASA Astrophysics Data System (ADS)

Hussain, Anwar; Martínez Fuentes, José Luis

2016-10-01

A super-resolution technique based on structured illumination created by a liquid crystal on silicon spatial light modulator (LCOS-SLM) is presented. Single and simultaneous pairs of tilted beams are generated to illuminate a target object. Resolution enhancement of an optical 4f system is demonstrated by using numerical simulations. The resulting intensity images are recorded at a charged couple device (CCD) and stored in the computer memory for further processing. One dimension enhancement can be performed with only 15 images. Two dimensional complete improvement requires 153 different images. The resolution of the optical system is extended three times compared to the band limited system.

Computational Models of Human Performance: Validation of Memory and Procedural Representation in Advanced Air/Ground Simulation

NASA Technical Reports Server (NTRS)

Corker, Kevin M.; Labacqz, J. Victor (Technical Monitor)

1997-01-01

The Man-Machine Interaction Design and Analysis System (MIDAS) under joint U.S. Army and NASA cooperative is intended to assist designers of complex human/automation systems in successfully incorporating human performance capabilities and limitations into decision and action support systems. MIDAS is a computational representation of multiple human operators, selected perceptual, cognitive, and physical functions of those operators, and the physical/functional representation of the equipment with which they operate. MIDAS has been used as an integrated predictive framework for the investigation of human/machine systems, particularly in situations with high demands on the operators. We have extended the human performance models to include representation of both human operators and intelligent aiding systems in flight management, and air traffic service. The focus of this development is to predict human performance in response to aiding system developed to identify aircraft conflict and to assist in the shared authority for resolution. The demands of this application requires representation of many intelligent agents sharing world-models, coordinating action/intention, and cooperative scheduling of goals and action in an somewhat unpredictable world of operations. In recent applications to airborne systems development, MIDAS has demonstrated an ability to predict flight crew decision-making and procedural behavior when interacting with automated flight management systems and Air Traffic Control. In this paper, we describe two enhancements to MIDAS. The first involves the addition of working memory in the form of an articulatory buffer for verbal communication protocols and a visuo-spatial buffer for communications via digital datalink. The second enhancement is a representation of multiple operators working as a team. This enhanced model was used to predict the performance of human flight crews and their level of compliance with commercial aviation communication procedures. We show how the data produced by MIDAS compares with flight crew performance data from full mission simulations. Finally, we discuss the use of these features to study communication issues connected with aircraft-based separation assurance.

Using Internet Technologies To Enhance Training.

ERIC Educational Resources Information Center

Pollock, Carl; Masters, Robert

1997-01-01

Describes how to use Internet technologies to create an intranet, or an online training database system, for improving company communications, effectiveness, and job performance. Topics include technology and performance; educating managers and key decision makers; creating a graphic model of the training system; and fitting into the existing…

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

NASA Astrophysics Data System (ADS)

Nayar, Priya; Singh, Bhim; Mishra, Sukumar

2017-08-01

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

Ensemble LUT classification for degraded document enhancement

NASA Astrophysics Data System (ADS)

Obafemi-Ajayi, Tayo; Agam, Gady; Frieder, Ophir

2008-01-01

The fast evolution of scanning and computing technologies have led to the creation of large collections of scanned paper documents. Examples of such collections include historical collections, legal depositories, medical archives, and business archives. Moreover, in many situations such as legal litigation and security investigations scanned collections are being used to facilitate systematic exploration of the data. It is almost always the case that scanned documents suffer from some form of degradation. Large degradations make documents hard to read and substantially deteriorate the performance of automated document processing systems. Enhancement of degraded document images is normally performed assuming global degradation models. When the degradation is large, global degradation models do not perform well. In contrast, we propose to estimate local degradation models and use them in enhancing degraded document images. Using a semi-automated enhancement system we have labeled a subset of the Frieder diaries collection.1 This labeled subset was then used to train an ensemble classifier. The component classifiers are based on lookup tables (LUT) in conjunction with the approximated nearest neighbor algorithm. The resulting algorithm is highly effcient. Experimental evaluation results are provided using the Frieder diaries collection.1

Use and Protection of GPS Sidelobe Signals for Enhanced Navigation Performance in High Earth Orbit

NASA Technical Reports Server (NTRS)

Parker, Joel J. K.; Valdez, Jennifer E.; Bauer, Frank H.; Moreau, Michael C.

2016-01-01

GPS (Global Positioning System) Space Service Volume (SSV) signal environment is from 3,000-36,000 kilometers altitude. Current SSV specifications only capture performance provided by signals transmitted within 23.5(L1) or 26(L2-L5) off-nadir angle. Recent on-orbit data lessons learned show significant PNT (Positioning, Navigation and Timing) performance improvements when the full aggregate signal is used. Numerous military civil operational missions in High Geosynchronous Earth Orbit (HEOGEO) utilize the full signal to enhance vehicle PNT performance

Performance Improvement Assuming Complexity

ERIC Educational Resources Information Center

Rowland, Gordon

2007-01-01

Individual performers, work teams, and organizations may be considered complex adaptive systems, while most current human performance technologies appear to assume simple determinism. This article explores the apparent mismatch and speculates on future efforts to enhance performance if complexity rather than simplicity is assumed. Included are…

Nanostructure enhanced ionic transport in fullerene reinforced solid polymer electrolytes.

PubMed

Sun, Che-Nan; Zawodzinski, Thomas A; Tenhaeff, Wyatt E; Ren, Fei; Keum, Jong Kahk; Bi, Sheng; Li, Dawen; Ahn, Suk-Kyun; Hong, Kunlun; Rondinone, Adam J; Carrillo, Jan-Michael Y; Do, Changwoo; Sumpter, Bobby G; Chen, Jihua

2015-03-28

Solid polymer electrolytes, such as polyethylene oxide (PEO) based systems, have the potential to replace liquid electrolytes in secondary lithium batteries with flexible, safe, and mechanically robust designs. Previously reported PEO nanocomposite electrolytes routinely use metal oxide nanoparticles that are often 5-10 nm in diameter or larger. The mechanism of those oxide particle-based polymer nanocomposite electrolytes is under debate and the ion transport performance of these systems is still to be improved. Herein we report a 6-fold ion conductivity enhancement in PEO/lithium bis(trifluoromethanesulfonyl) imide (LiTFSI)-based solid electrolytes upon the addition of fullerene derivatives. The observed conductivity improvement correlates with nanometer-scale fullerene crystallite formation, reduced crystallinities of both the (PEO)6:LiTFSI phase and pure PEO, as well as a significantly larger PEO free volume. This improved performance is further interpreted by enhanced decoupling between ion transport and polymer segmental motion, as well as optimized permittivity and conductivity in bulk and grain boundaries. This study suggests that nanoparticle induced morphological changes, in a system with fullerene nanoparticles and no Lewis acidic sites, play critical roles in their ion conductivity enhancement. The marriage of fullerene derivatives and solid polymer electrolytes opens up significant opportunities in designing next-generation solid polymer electrolytes with improved performance.

Investigation of fiber dispersion impairment in 400GbE discrete multi-tone system for reach enhancement up to 40 km

NASA Astrophysics Data System (ADS)

Okabe, Ryo; Tanaka, Toshiki; Nishihara, Masato; Kai, Yutaka; Takahara, Tomoo; Chen, Hao; Yan, Weizhen; Tao, Zhenning; Rasmussen, Jens C.

2015-01-01

Discrete multi-tone (DMT) technology is an attractive modulation technique for short reach optical transmission system. One of the main factors that limit system performance is fiber dispersion, which is strongly influenced by the chirp characteristics of transmitters. We investigated the fiber dispersion impairment in a 400GbE (4 × 116.1-Gb/s) DMT system on LAN-WDM grid for reach enhancement up to 40 km through experiments and numerical simulations.

The short-term stress response - Mother nature's mechanism for enhancing protection and performance under conditions of threat, challenge, and opportunity.

PubMed

Dhabhar, Firdaus S

2018-03-26

Our group has proposed that in contrast to chronic stress that can have harmful effects, the short-term (fight-or-flight) stress response (lasting for minutes to hours) is nature's fundamental survival mechanism that enhances protection and performance under conditions involving threat/challenge/opportunity. Short-term stress enhances innate/primary, adaptive/secondary, vaccine-induced, and anti-tumor immune responses, and post-surgical recovery. Mechanisms and mediators include stress hormones, dendritic cell, neutrophil, macrophage, and lymphocyte trafficking/function and local/systemic chemokine and cytokine production. Short-term stress may also enhance mental/cognitive and physical performance through effects on brain, musculo-skeletal, and cardiovascular function, reappraisal of threat/anxiety, and training-induced stress-optimization. Therefore, short-term stress psychology/physiology could be harnessed to enhance immuno-protection, as well as mental and physical performance. This review aims to provide a conceptual framework and targets for further investigation of mechanisms and conditions under which the protective/adaptive aspects of short-term stress/exercise can be optimized/harnessed, and for developing pharmacological/biobehavioral interventions to enhance health/healing, and mental/cognitive/physical performance. Copyright © 2018 Elsevier Inc. All rights reserved.

Laser systems for the combustion research facility - Diana

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

Miller, C.K.; Lavasek, J.W.; Jones, E.D.

1982-03-01

A 5-Joule/pulse, 1.8-..mu..s-pulse-width, 10-ppS flashlamp-pumped tunable-dye-laser system, called Diana, has been built for use in experiments to be performed at the Combustion Research Facility, Sandia National Laboratories, Livermore. Design specifications for the system and details of construction are described, and it is noted that performance of the laser meets or exceeds all design criteria. Areas for further performance improvements are discussed, and updates are suggested to enhance system usefulness.

Performance Evaluation of Single Sideband Radio over Fiber System through Modulation Index Enhancement

NASA Astrophysics Data System (ADS)

Chen, Xiaogang; Hu, Xizhen; Huang, Dexiu

2014-09-01

The transmission performance of single sideband (SSB) radio over fiber (RoF) system is evaluated through tuning the modulation index of Mach-Zehnder modulator, two different data modulation schemes and the influence of fiber dispersion are considered. The quantitative simulation results validate that there exist an optimum modulation index, and the system performance could be improved if the data signal is modulated on only optical carrier or sidebands.

Enhanced performance of a filter-sensor system.

PubMed

Sasaki, Isao; Josowicz, Mira; Janata, Jirí; Glezer, Ari

2006-06-01

In this paper are addressed two important, but seemingly unrelated issues: long term performance of a gas sensing array and performance of an air purification unit. It is shown that when considered together, the system can be regarded as a "smart filter". The enhancement is achieved by periodic differential sampling and measurement of the "upstream" and "downstream" gases of a filter. The correctly functioning filter supplies the "zero gas" from the downstream for the continuous sensor baseline correction. A key element in this scheme is the synthetic jet that delivers well-defined pulses of the two gases. The deterioration of the performance of the "smart filter" can be diagnosed from the response pattern of the sensor. The approach has been demonstrated on removal/sensing of ammonia gas from air.

Effect of sludge retention time on continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.

PubMed

Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

2016-11-01

The effect of sludge retention time (SRT) on the continuous-flow system with enhanced biological phosphorus removal (EBPR) granules at different COD loading was investigated during the operation of more than 220days. And the results showed that when the system operated at long SRT (30days) and low COD loading (200mg·L(-1)), it could maintain excellent performance. However, long SRT and high COD loading (300mg·L(-1)) deteriorated the settling ability of granules and the performance of system and resulted in the overgrowth of filamentous bacteria. Meanwhile, the transformation of poly-β-hydroxyalkanoates (PHAs) and glycogen in metabolism process was inhibited. Moreover, the results of pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading and long SRT. The PAOs specious of Candidatus_Accumlibater and system performance increased obviously when the SRT was reduced to 20days at high COD loading. Copyright © 2016 Elsevier Ltd. All rights reserved.

IMIS: Integrated Maintenance Information System. A maintenance information delivery concept

NASA Technical Reports Server (NTRS)

Vonholle, Joseph C.

1987-01-01

The Integrated Maintenance Information System (IMIS) will optimize the use of available manpower, enhance technical performance, improve training, and reduce the support equipment and documentation needed for deployment. It will serve as the technician's single, integrated source of all the technical information required to perform modern aircraft maintenance.

Standard Hardware Acquisition and Reliability Program's (SHARP's) efforts in incorporating fiber optic interconnects into standard electronic module (SEM) connectors

NASA Astrophysics Data System (ADS)

Riggs, William R.

1994-05-01

SHARP is a Navy wide logistics technology development effort aimed at reducing the acquisition costs, support costs, and risks of military electronic weapon systems while increasing the performance capability, reliability, maintainability, and readiness of these systems. Lower life cycle costs for electronic hardware are achieved through technology transition, standardization, and reliability enhancement to improve system affordability and availability as well as enhancing fleet modernization. Advanced technology is transferred into the fleet through hardware specifications for weapon system building blocks of standard electronic modules, standard power systems, and standard electronic systems. The product lines are all defined with respect to their size, weight, I/O, environmental performance, and operational performance. This method of defining the standard is very conducive to inserting new technologies into systems using the standard hardware. This is the approach taken thus far in inserting photonic technologies into SHARP hardware. All of the efforts have been related to module packaging; i.e. interconnects, component packaging, and module developments. Fiber optic interconnects are discussed in this paper.

An accurate evaluation of the performance of asynchronous DS-CDMA systems with zero-correlation-zone coding in Rayleigh fading

NASA Astrophysics Data System (ADS)

Walker, Ernest; Chen, Xinjia; Cooper, Reginald L.

2010-04-01

An arbitrarily accurate approach is used to determine the bit-error rate (BER) performance for generalized asynchronous DS-CDMA systems, in Gaussian noise with Raleigh fading. In this paper, and the sequel, new theoretical work has been contributed which substantially enhances existing performance analysis formulations. Major contributions include: substantial computational complexity reduction, including a priori BER accuracy bounding; an analytical approach that facilitates performance evaluation for systems with arbitrary spectral spreading distributions, with non-uniform transmission delay distributions. Using prior results, augmented by these enhancements, a generalized DS-CDMA system model is constructed and used to evaluated the BER performance, in a variety of scenarios. In this paper, the generalized system modeling was used to evaluate the performance of both Walsh- Hadamard (WH) and Walsh-Hadamard-seeded zero-correlation-zone (WH-ZCZ) coding. The selection of these codes was informed by the observation that WH codes contain N spectral spreading values (0 to N - 1), one for each code sequence; while WH-ZCZ codes contain only two spectral spreading values (N/2 - 1,N/2); where N is the sequence length in chips. Since these codes span the spectral spreading range for DS-CDMA coding, by invoking an induction argument, the generalization of the system model is sufficiently supported. The results in this paper, and the sequel, support the claim that an arbitrary accurate performance analysis for DS-CDMA systems can be evaluated over the full range of binary coding, with minimal computational complexity.

Advanced composite structural concepts and materials technologies for primary aircraft structures: Advanced material concepts

NASA Technical Reports Server (NTRS)

Lau, Kreisler S. Y.; Landis, Abraham L.; Chow, Andrea W.; Hamlin, Richard D.

1993-01-01

To achieve acceptable performance and long-term durability at elevated temperatures (350 to 600 F) for high-speed transport systems, further improvements of the high-performance matrix materials will be necessary to achieve very long-term (60,000-120,000 service hours) retention of mechanical properties and damage tolerance. This report emphasizes isoimide modification as a complementary technique to semi-interpenetrating polymer networks (SIPN's) to achieve greater processibility, better curing dynamics, and possibly enhanced thermo-mechanical properties in composites. A key result is the demonstration of enhanced processibility of isoimide-modified linear and thermo-setting polyimide systems.

Primary lithium battery technology and its application to NASA missions

NASA Technical Reports Server (NTRS)

Frank, H. A.

1979-01-01

A description is given of the components, overall cell reactions, and performance characteristics of promising new ambient temperature lithium primary systems based on the Li-V205, Li-SO2, and Li-SOC12 couples. Development status of these systems is described in regard to availability and uncertainties in the areas of safety and selected performance characteristics. Studies show that use of lithium batteries would enhance a variety of missions and applications by decreasing power sytems weight and thereby increasing payload weight. In addition, the lithium batteries could enhance cost effectiveness of the missions.

Enhanced fault-tolerant quantum computing in d-level systems.

PubMed

Campbell, Earl T

2014-12-05

Error-correcting codes protect quantum information and form the basis of fault-tolerant quantum computing. Leading proposals for fault-tolerant quantum computation require codes with an exceedingly rare property, a transversal non-Clifford gate. Codes with the desired property are presented for d-level qudit systems with prime d. The codes use n=d-1 qudits and can detect up to ∼d/3 errors. We quantify the performance of these codes for one approach to quantum computation known as magic-state distillation. Unlike prior work, we find performance is always enhanced by increasing d.

Enhanced Component Performance Study. Emergency Diesel Generators 1998–2013

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

Schroeder, John Alton

2014-11-01

This report presents an enhanced performance evaluation of emergency diesel generators (EDGs) at U.S. commercial nuclear power plants. This report evaluates component performance over time using Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES) data from 1998 through 2013 and maintenance unavailability (UA) performance data using Mitigating Systems Performance Index (MSPI) Basis Document data from 2002 through 2013. The objective is to present an analysis of factors that could influence the system and component trends in addition to annual performance trends of failure rates and probabilities. The factors analyzed for the EDG component are the differences in failuresmore » between all demands and actual unplanned engineered safety feature (ESF) demands, differences among manufacturers, and differences among EDG ratings. Statistical analyses of these differences are performed and results showing whether pooling is acceptable across these factors. In addition, engineering analyses were performed with respect to time period and failure mode. The factors analyzed are: sub-component, failure cause, detection method, recovery, manufacturer, and EDG rating.« less

Assessment of the Impact of Smart Board Technology System Use on Student Learning, Satisfaction, and Performance

ERIC Educational Resources Information Center

Warnock, Stuart H.; Boykin, Nancy J.; Tung, Wei Chih

2011-01-01

Literature on educational technology touts its potential for enhancing student outcomes such as learning, satisfaction, and performance. But are these benefits universal and do they apply to all applications and/or forms of educational technology? This study focuses on one such system, the Smart Board Technology System (SBTS) and the impact its…

Comparison of a brain-based adaptive system and a manual adaptable system for invoking automation.

PubMed

Bailey, Nathan R; Scerbo, Mark W; Freeman, Frederick G; Mikulka, Peter J; Scott, Lorissa A

2006-01-01

Two experiments are presented examining adaptive and adaptable methods for invoking automation. Empirical investigations of adaptive automation have focused on methods used to invoke automation or on automation-related performance implications. However, no research has addressed whether performance benefits associated with brain-based systems exceed those in which users have control over task allocations. Participants performed monitoring and resource management tasks as well as a tracking task that shifted between automatic and manual modes. In the first experiment, participants worked with an adaptive system that used their electroencephalographic signals to switch the tracking task between automatic and manual modes. Participants were also divided between high- and low-reliability conditions for the system-monitoring task as well as high- and low-complacency potential. For the second experiment, participants operated an adaptable system that gave them manual control over task allocations. Results indicated increased situation awareness (SA) of gauge instrument settings for individuals high in complacency potential using the adaptive system. In addition, participants who had control over automation performed more poorly on the resource management task and reported higher levels of workload. A comparison between systems also revealed enhanced SA of gauge instrument settings and decreased workload in the adaptive condition. The present results suggest that brain-based adaptive automation systems may enhance perceptual level SA while reducing mental workload relative to systems requiring user-initiated control. Potential applications include automated systems for which operator monitoring performance and high-workload conditions are of concern.

Neural network-based systems for handprint OCR applications.

PubMed

Ganis, M D; Wilson, C L; Blue, J L

1998-01-01

Over the last five years or so, neural network (NN)-based approaches have been steadily gaining performance and popularity for a wide range of optical character recognition (OCR) problems, from isolated digit recognition to handprint recognition. We present an NN classification scheme based on an enhanced multilayer perceptron (MLP) and describe an end-to-end system for form-based handprint OCR applications designed by the National Institute of Standards and Technology (NIST) Visual Image Processing Group. The enhancements to the MLP are based on (i) neuron activations functions that reduce the occurrences of singular Jacobians; (ii) successive regularization to constrain the volume of the weight space; and (iii) Boltzmann pruning to constrain the dimension of the weight space. Performance characterization studies of NN systems evaluated at the first OCR systems conference and the NIST form-based handprint recognition system are also summarized.

DSN system performance test software

NASA Technical Reports Server (NTRS)

Martin, M.

1978-01-01

The system performance test software is currently being modified to include additional capabilities and enhancements. Additional software programs are currently being developed for the Command Store and Forward System and the Automatic Total Recall System. The test executive is the main program. It controls the input and output of the individual test programs by routing data blocks and operator directives to those programs. It also processes data block dump requests from the operator.

Performance and cost improvements in the display control module for DVE

NASA Astrophysics Data System (ADS)

Thomas, J.; Lorimer, S.,

2009-05-01

The DCM for the Drivers Vision Enhancer system is the display part of a relatively low cost IR imaging system for land-vehicles. Recent changes to operational needs, associated with asymmetrical warfare have added daytime operations to the uses for this mature system. This paper will discuss cost/performance tradeoffs and provide thoughts for "DVE of the future" in light of these new operational needs for the system.

Improving human object recognition performance using video enhancement techniques

NASA Astrophysics Data System (ADS)

Whitman, Lucy S.; Lewis, Colin; Oakley, John P.

2004-12-01

Atmospheric scattering causes significant degradation in the quality of video images, particularly when imaging over long distances. The principle problem is the reduction in contrast due to scattered light. It is known that when the scattering particles are not too large compared with the imaging wavelength (i.e. Mie scattering) then high spatial resolution information may be contained within a low-contrast image. Unfortunately this information is not easily perceived by a human observer, particularly when using a standard video monitor. A secondary problem is the difficulty of achieving a sharp focus since automatic focus techniques tend to fail in such conditions. Recently several commercial colour video processing systems have become available. These systems use various techniques to improve image quality in low contrast conditions whilst retaining colour content. These systems produce improvements in subjective image quality in some situations, particularly in conditions of haze and light fog. There is also some evidence that video enhancement leads to improved ATR performance when used as a pre-processing stage. Psychological literature indicates that low contrast levels generally lead to a reduction in the performance of human observers in carrying out simple visual tasks. The aim of this paper is to present the results of an empirical study on object recognition in adverse viewing conditions. The chosen visual task was vehicle number plate recognition at long ranges (500 m and beyond). Two different commercial video enhancement systems are evaluated using the same protocol. The results show an increase in effective range with some differences between the different enhancement systems.

Baseline Testing of the Ultracapacitor Enhanced Photovoltaic Power Station

NASA Technical Reports Server (NTRS)

Eichenberg, Dennis J.; Kolacz, John S.; Tavernelli, Paul F.

2001-01-01

The NASA John H. Glenn Research Center is developing an advanced ultracapacitor enhanced photovoltaic power station. Goals of this effort include maximizing photovoltaic power generation efficiency and extending the life of photovoltaic energy storage systems. Unique aspects of the power station include the use of a solar tracker, and ultracapacitors for energy storage. The photovoltaic power station is seen as a way to provide electric power in remote locations that would otherwise not have electric power, provide independence form utility systems, reduce pollution, reduce fossil fuel consumption, and reduce operating costs. The work was done under the Hybrid Power Management (HPM) Program, which includes the Hybrid Electric Transit Bus (HETB), and the E-Bike. The power station complements the E-Bike extremely well in that it permits the charging of the vehicle batteries in remote locations. Other applications include scientific research and medical power sources in isolated regions. The power station is an inexpensive approach to advance the state of the art in power technology in a practical application. The project transfers space technology to terrestrial use via nontraditional partners, and provides power system data valuable for future space applications. A description of the ultracapacitor enhanced power station, the results of performance testing and future power station development plans is the subject of this report. The report concludes that the ultracapacitor enhanced power station provides excellent performance, and that the implementation of ultracapacitors in the power system can provide significant performance improvements.

System performance enhancement with pre-distorted OOFDM signal waveforms in DM/DD systems.

PubMed

Sánchez, C; Ortega, B; Capmany, J

2014-03-24

In this work we propose a pre-distortion technique for the mitigation of the nonlinear distortion present in directly modulated/detected OOFDM systems and explore the system performance achieved under varying system parameters. Simulation results show that the proposed pre-distortion technique efficiently mitigates the nonlinear distortion, achieving transmission information rates around 40 Gbits/s and 18.5 Gbits/s over 40 km and 100 km of single mode fiber links, respectively, under optimum operating conditions. Moreover, the proposed pre-distortion technique can potentially provide higher system performance to that obtained with nonlinear equalization at the receiver.

The use of medical quality indices as a performance-enhancement tool for community clinics.

PubMed

Elhayany, A

2001-12-01

One of the most important issues for a country, its population and doctors is the effective use of its health system. The extensive variation in doctors' performance leads to a tremendous waste of resources. To combat this, and at the same time ensure that medical quality plays a role when making decisions on interventions, it is essential to equip doctors and clinic directors with information on the quality of the medical care they are providing. In order to assist clinic directors in maintaining medical quality, Clalit Health Services has developed comparative medical indices enabling doctors to compare their performance to that of their colleagues, as well as to the standard and their performance over time. The development of an index to evaluate the quality of medical treatment offered in clinics provides doctors and the health system with an essential tool to lessen the existing variation among doctors and to enhance and evaluate performance.

Optimization of a Small-Scale Engine Using Plasma Enhanced Ignition

DTIC Science & Technology

2013-03-01

PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT...systems were tested in the small engine and their effects on engine performance determined through comparison with a regular spark discharge (thermal...pulse plasma discharge system purchased from Plasmatronics LLC. Air fuel ratio (λ units are used in this report) sweeps were performed at several

Application of shape memory alloy (SMA) spars for aircraft maneuver enhancement

NASA Astrophysics Data System (ADS)

Nam, Changho; Chattopadhyay, Aditi; Kim, Youdan

2002-07-01

Modern combat aircraft are required to achieve aggressive maneuverability and high agility performance, while maintaining handling qualities over a wide range of flight conditions. Recently, a new adaptive-structural concept called variable stiffness spar is proposed in order to increase the maneuverability of the flexible aircraft. The variable stiffness spar controls wing torsional stiffness to enhance roll performance in the complete flight envelope. However, variable stiffness spar requires the mechanical actuation system in order to rotate the Variable stiffness spar during flight. The mechanical actuation system to rotate variable stiffness spar may cause an additional weight increase. In this paper, we will apply Shape Memory Alloy (SMA) spars for aeroelastic performance enhancement. In order to explore the potential of SMA spar design, roll performance of the composite smart wings will be investigated using ASTROS. Parametric study will be conducted to investigate the SMA spar effects by changing the spar locations and geometry. The results show that with activation of the SMA spar, the roll effectiveness can be increased up to 61% compared with the baseline model.

Development of optimized techniques and requirements for computer enhancement of structural weld radiographs. Volume 1: Technical report

NASA Technical Reports Server (NTRS)

Adams, J. R.; Hawley, S. W.; Peterson, G. R.; Salinger, S. S.; Workman, R. A.

1971-01-01

A hardware and software specification covering requirements for the computer enhancement of structural weld radiographs was considered. Three scanning systems were used to digitize more than 15 weld radiographs. The performance of these systems was evaluated by determining modulation transfer functions and noise characteristics. Enhancement techniques were developed and applied to the digitized radiographs. The scanning parameters of spot size and spacing and film density were studied to optimize the information content of the digital representation of the image.

Biofilm formation and microbial community analysis of the simulated river bioreactor for contaminated source water remediation.

PubMed

Xu, Xiang-Yang; Feng, Li-Juan; Zhu, Liang; Xu, Jing; Ding, Wei; Qi, Han-Ying

2012-06-01

The start-up pattern of biofilm remediation system affects the biofilm characteristics and operating performances. The objective of this study was to evaluate the performances of the contaminated source water remediation systems with different start-up patterns in view of the pollutants removal performances and microbial community succession. The operating performances of four lab-scale simulated river biofilm reactors were examined which employed different start-up methods (natural enrichment and artificial enhancement via discharging sediment with influent velocity gradient increase) and different bio-fillers (Elastic filler and AquaMats® ecobase). At the same time, the microbial communities of the bioreactors in different phases were analyzed by polymerase chain reaction, denaturing gradient gel electrophoresis, and sequencing. The pollutants removal performances became stable in the four reactors after 2 months' operation, with ammonia nitrogen and permanganate index (COD(Mn)) removal efficiencies of 84.41-94.21% and 69.66-76.60%, respectively. The biomass of mature biofilm was higher in the bioreactors by artificial enhancement than that by natural enrichment. Microbial community analysis indicated that elastic filler could enrich mature biofilm faster than AquaMats®. The heterotrophic bacteria diversity of biofilm decreased by artificial enhancement, which favored the ammonia-oxidizing bacteria (AOB) developing on the bio-fillers. Furthermore, Nitrosomonas- and Nitrosospira-like AOB coexisted in the biofilm, and Pseudomonas sp., Sphaerotilus sp., Janthinobacterium sp., Corynebacterium aurimucosum were dominant in the oligotrophic niche. Artificial enhancement via the combination of sediment discharging and influent velocity gradient increasing could enhance the biofilm formation and autotrophic AOB enrichment in oligotrophic niche.

Boundary Conditions of the High-Investment Human Resource Systems-Small-Firm Labor Productivity Relationship

ERIC Educational Resources Information Center

Chadwick, Clint; Way, Sean A.; Kerr, Gerry; Thacker, James W.

2013-01-01

Although a few published, multiindustry, firm-level, empirical studies have linked systems of high-investment or high-performance human resource management practices to enhanced small-firm performance, this stream of strategic human resource management research is underdeveloped and equivocal. Accordingly, in this study, we use a sample of…

Enhanced performance of microbial fuel cell with a bacteria/multi-walled carbon nanotube hybrid biofilm

NASA Astrophysics Data System (ADS)

Zhang, Peng; Liu, Jia; Qu, Youpeng; Zhang, Jian; Zhong, Yingjuan; Feng, Yujie

2017-09-01

The biofilm on the anode of a microbial fuel cell (MFC) is a vital component in system, and its formation and characteristic determines the performance of the system. In this study, a bacteria/Multi-Walled Carbon Nanotube (MWCNT) hybrid biofilm is fabricated by effectively inserting the MWCNTs into the anode biofilm via an adsorption-filtration method. This hybrid biofilm has been demonstrated to be an efficient structure for improving an anode biofilm performance. Electrochemical impedance spectroscopy (EIS) results show that the hybrid biofilm takes advantage of the conductivity and structure of MWCNT to enhance the electron transfer and substrate diffusion of the biofilm. With this hybrid biofilm, the current density, power density and coulombic efficiency are increased by 46.2%, 58.8% and 84.6%, respectively, relative to naturally grown biofilm. Furthermore, the start-up time is reduced by 53.8% compared with naturally grown biofilm. The perturbation test demonstrates that this type of hybrid biofilm exhibits strong adsorption ability and enhances the biofilm's resistance to a sudden change of substrate concentration. The superior performance of the hybrid biofilm with MWCNT ;nanowire; matrix compared with naturally grown biofilm demonstrates its great potential for boosting the performance of MFCs.

ASSESSMENT OF A WIND TURBINE INTELLIGENT CONTROLLER FOR ENHANCED ENERGY PRODUCTION AND POLLUTION REDUCTION

EPA Science Inventory

This study assessed the enhanced energy production which is possible when variable-speed wind turbines are electronically controlled by an intelligent controller for efficiency optimization and performance improvement. The control system consists of three fuzzy- logic controllers...

Pervious concrete research facility : winter performance and enhancement of pollutants removal.

DOT National Transportation Integrated Search

2013-12-01

The purpose of the current study was to design and test a porous medium that can potentially be applied in : pervious pavement systems. The principle goals were to identify a material capable of enhancing the PAH : sorption capacity, thereby mitigati...

Propulsion Health Monitoring for Enhanced Safety

NASA Technical Reports Server (NTRS)

Butz, Mark G.; Rodriguez, Hector M.

2003-01-01

This report presents the results of the NASA contract Propulsion System Health Management for Enhanced Safety performed by General Electric Aircraft Engines (GE AE), General Electric Global Research (GE GR), and Pennsylvania State University Applied Research Laboratory (PSU ARL) under the NASA Aviation Safety Program. This activity supports the overall goal of enhanced civil aviation safety through a reduction in the occurrence of safety-significant propulsion system malfunctions. Specific objectives are to develop and demonstrate vibration diagnostics techniques for the on-line detection of turbine rotor disk cracks, and model-based fault tolerant control techniques for the prevention and mitigation of in-flight engine shutdown, surge/stall, and flameout events. The disk crack detection work was performed by GE GR which focused on a radial-mode vibration monitoring technique, and PSU ARL which focused on a torsional-mode vibration monitoring technique. GE AE performed the Model-Based Fault Tolerant Control work which focused on the development of analytical techniques for detecting, isolating, and accommodating gas-path faults.

A Review: Enhanced Anodes of Li/Na-Ion Batteries Based on Yolk-Shell Structured Nanomaterials

NASA Astrophysics Data System (ADS)

Wu, Cuo; Tong, Xin; Ai, Yuanfei; Liu, De-Sheng; Yu, Peng; Wu, Jiang; Wang, Zhiming M.

2018-09-01

Lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk-shell (YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail. [Figure not available: see fulltext.

Using Intelligent Simulation to Enhance Human Performance in Aircraft Maintenance

NASA Technical Reports Server (NTRS)

Johnson, William B.; Norton, Jeffrey E.

1992-01-01

Human factors research and development investigates the capabilities and limitations of the human within a system. Of the many variables affecting human performance in the aviation maintenance system, training is among the most important. The advent of advanced technology hardware and software has created intelligent training simulations. This paper describes one advanced technology training system under development for the Federal Aviation Administration.

Effective Team Support: From Task and Cognitive Modeling to Software Agents for Time-Critical Complex Work Environments

NASA Technical Reports Server (NTRS)

Remington, Roger W. (Technical Monitor); John, Bonnie E.; Sycara, Katia

2005-01-01

The purpose of this research contract was to perform multidisciplinary research between CMU psychologists, computer scientists and NASA researchers to design a next generation collaborative system to support a team of human experts and intelligent agents. To achieve robust performance enhancement of such a system, we had proposed to perform task and cognitive modeling to thoroughly understand the impact technology makes on the organization and on key individual personnel. Guided by cognitively-inspired requirements, we would then develop software agents that support the human team in decision making, information filtering, information distribution and integration to enhance team situational awareness. During the period covered by this final report, we made substantial progress in completing a system for empirical data collection, cognitive modeling, and the building of software agents to support a team's tasks, and in running experiments for the collection of baseline data.

Applications of Endothermic Reaction Technology to the High Speed Civil Transport

NASA Technical Reports Server (NTRS)

Glickstein, Marvin R.; Spadaccini, Louis J.

1998-01-01

The success of strategies for controlling emissions and enhancing performance in High Speed Research applications may be Increased by more effective utilization of the heat sink afforded by the fuel in the vehicle thermal management system. This study quantifies the potential benefits associated with the use of supercritical preheating and endothermic cracking of let fuel prior to combustion to enhance the thermal management capabilities of the propulsion systems in the High Speed Civil Transport (HSCT). A fuel-cooled thermal management system, consisting of plate-fin heat exchangers and a small auxiliary compressor, is defined for the HSCT, Integrated with the engine, and an assessment of the effect on engine performance, weight, and operating cost is performed. The analysis indicates significant savings due a projected improvement in fuel economy, and the potential for additional benefit if the cycle is modified to take full advantage of all the heat sink available in the fuel.

Duplicate and Conquer: Multiple Homologs of PHOSPHORUS-STARVATION TOLERANCE1 Enhance Phosphorus Acquisition and Sorghum Performance on Low-Phosphorus Soils1[C][W][OPEN

PubMed Central

Hufnagel, Barbara; de Sousa, Sylvia M.; Assis, Lidianne; Guimaraes, Claudia T.; Leiser, Willmar; Azevedo, Gabriel C.; Negri, Barbara; Larson, Brandon G.; Shaff, Jon E.; Pastina, Maria Marta; Barros, Beatriz A.; Weltzien, Eva; Rattunde, Henry Frederick W.; Viana, Joao H.; Clark, Randy T.; Falcão, Alexandre; Gazaffi, Rodrigo; Garcia, Antonio Augusto F.; Schaffert, Robert E.; Kochian, Leon V.; Magalhaes, Jurandir V.

2014-01-01

Low soil phosphorus (P) availability is a major constraint for crop production in tropical regions. The rice (Oryza sativa) protein kinase, PHOSPHORUS-STARVATION TOLERANCE1 (OsPSTOL1), was previously shown to enhance P acquisition and grain yield in rice under P deficiency. We investigated the role of homologs of OsPSTOL1 in sorghum (Sorghum bicolor) performance under low P. Association mapping was undertaken in two sorghum association panels phenotyped for P uptake, root system morphology and architecture in hydroponics and grain yield and biomass accumulation under low-P conditions, in Brazil and/or in Mali. Root length and root surface area were positively correlated with grain yield under low P in the soil, emphasizing the importance of P acquisition efficiency in sorghum adaptation to low-P availability. SbPSTOL1 alleles reducing root diameter were associated with enhanced P uptake under low P in hydroponics, whereas Sb03g006765 and Sb03g0031680 alleles increasing root surface area also increased grain yield in a low-P soil. SbPSTOL1 genes colocalized with quantitative trait loci for traits underlying root morphology and dry weight accumulation under low P via linkage mapping. Consistent allelic effects for enhanced sorghum performance under low P between association panels, including enhanced grain yield under low P in the soil in Brazil, point toward a relatively stable role for Sb03g006765 across genetic backgrounds and environmental conditions. This study indicates that multiple SbPSTOL1 genes have a more general role in the root system, not only enhancing root morphology traits but also changing root system architecture, which leads to grain yield gain under low-P availability in the soil. PMID:25189534

Research on the enhancement of biological nitrogen removal at low temperatures from ammonium-rich wastewater by the bio-electrocoagulation technology in lab-scale systems, pilot-scale systems and a full-scale industrial wastewater treatment plant.

PubMed

Li, Liang; Qian, Guangsheng; Ye, Linlin; Hu, Xiaomin; Yu, Xin; Lyu, Weijian

2018-09-01

In cold areas, nitrogen removal performance of wastewater treatment plants (WWTP) declines greatly in winter. This paper systematically describes the enhancement effect of a periodic reverse electrocoagulation technology on biological nitrogen removal at low temperatures. The study showed that in the lab-scale systems, the electrocoagulation technology improved the biomass amount, enzyme activity and the amount of nitrogen removal bacteria (Nitrosomonas, Nitrobacter, Paracoccus, Thauera and Enterobacter). This enhanced nitrification and denitrification of activated sludge at low temperatures. In the pilot-scale systems, the electrocoagulation technology increased the relative abundance of cold-adapted microorganisms (Luteimonas and Trueperaceae) at low temperatures. In a full-scale industrial WWTP, comparison of data from winter 2015 and winter 2016 showed that effluent chemical oxygen demand (COD), NH 4 + -N, and NO 3 - -N reduced by 10.37, 3.84, and 136.43 t, respectively, throughout the winter, after installation of electrocoagulation devices. These results suggest that the electrocoagulation technology is able to improve the performance of activated sludge under low-temperature conditions. This technology provides a new way for upgrading of the performance of WWTPs in cold areas. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identification of siRNA delivery enhancers by a chemical library screen.

PubMed

Gilleron, Jerome; Paramasivam, Prasath; Zeigerer, Anja; Querbes, William; Marsico, Giovanni; Andree, Cordula; Seifert, Sarah; Amaya, Pablo; Stöter, Martin; Koteliansky, Victor; Waldmann, Herbert; Fitzgerald, Kevin; Kalaidzidis, Yannis; Akinc, Akin; Maier, Martin A; Manoharan, Muthiah; Bickle, Marc; Zerial, Marino

2015-09-18

Most delivery systems for small interfering RNA therapeutics depend on endocytosis and release from endo-lysosomal compartments. One approach to improve delivery is to identify small molecules enhancing these steps. It is unclear to what extent such enhancers can be universally applied to different delivery systems and cell types. Here, we performed a compound library screen on two well-established siRNA delivery systems, lipid nanoparticles and cholesterol conjugated-siRNAs. We identified fifty-one enhancers improving gene silencing 2-5 fold. Strikingly, most enhancers displayed specificity for one delivery system only. By a combination of quantitative fluorescence and electron microscopy we found that the enhancers substantially differed in their mechanism of action, increasing either endocytic uptake or release of siRNAs from endosomes. Furthermore, they acted either on the delivery system itself or the cell, by modulating the endocytic system via distinct mechanisms. Interestingly, several compounds displayed activity on different cell types. As proof of principle, we showed that one compound enhanced siRNA delivery in primary endothelial cells in vitro and in the endocardium in the mouse heart. This study suggests that a pharmacological approach can improve the delivery of siRNAs in a system-specific fashion, by exploiting distinct mechanisms and acting upon multiple cell types. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Spread spectrum time-resolved diffuse optical measurement system for enhanced sensitivity in detecting human brain activity

NASA Astrophysics Data System (ADS)

Mehta, Kalpesh; Hasnain, Ali; Zhou, Xiaowei; Luo, Jianwen; Penney, Trevor B.; Chen, Nanguang

2017-04-01

Diffuse optical spectroscopy (DOS) and imaging methods have been widely applied to noninvasive detection of brain activity. We have designed and implemented a low cost, portable, real-time one-channel time-resolved DOS system for neuroscience studies. Phantom experiments were carried out to test the performance of the system. We further conducted preliminary human experiments and demonstrated that enhanced sensitivity in detecting neural activity in the cortex could be achieved by the use of late arriving photons.

Synthetic and Enhanced Vision Systems for NextGen (SEVS) Simulation and Flight Test Performance Evaluation

NASA Technical Reports Server (NTRS)

Shelton, Kevin J.; Kramer, Lynda J.; Ellis,Kyle K.; Rehfeld, Sherri A.

2012-01-01

The Synthetic and Enhanced Vision Systems for NextGen (SEVS) simulation and flight tests are jointly sponsored by NASA's Aviation Safety Program, Vehicle Systems Safety Technology project and the Federal Aviation Administration (FAA). The flight tests were conducted by a team of Honeywell, Gulfstream Aerospace Corporation and NASA personnel with the goal of obtaining pilot-in-the-loop test data for flight validation, verification, and demonstration of selected SEVS operational and system-level performance capabilities. Nine test flights (38 flight hours) were conducted over the summer and fall of 2011. The evaluations were flown in Gulfstream.s G450 flight test aircraft outfitted with the SEVS technology under very low visibility instrument meteorological conditions. Evaluation pilots flew 108 approaches in low visibility weather conditions (600 ft to 2400 ft visibility) into various airports from Louisiana to Maine. In-situ flight performance and subjective workload and acceptability data were collected in collaboration with ground simulation studies at LaRC.s Research Flight Deck simulator.

Effect of Thermoelectric Cooling (TEC) module and the water flow heatsink on Photovoltaic (PV) panel performance

NASA Astrophysics Data System (ADS)

Amelia, A. R.; Jusoh, MA; Shamira Idris, Ida

2017-11-01

Photovoltaic (PV) panel suffers in low conversion efficiency of the output performance affected by the elevated operating temperature of the PV panel. It is important to keep the PV panel to operate at low temperature. To address this issue, this paper proposes the cooling system using thermoelectric cooling (TEC) and water block heatsink for enhancing the PV panel output performance. These both types cooling system were designed located on the back side of the PV panel to cool down the operating temperature of the PV panel. To evaluate the function for the existing cooling systems, the experiment was subsequently performed for PV panel without and with different design of the cooling system in outdoor weather conditions. By comparing the experimental results, it is concluded that by the hybrid cooling system which combining TEC module and the water block heatsink could improve the output performance of the PV panel. By the reduction temperature of the PV panel by 16.04 %, the average output power of the PV panel has been boosted up from 8.59 W to 9.03 W. In short, the output power of the PV panel was enhanced by the reduction of the operating temperature of the PV panel.

The role of privacy protection in healthcare information systems adoption.

PubMed

Hsu, Chien-Lung; Lee, Ming-Ren; Su, Chien-Hui

2013-10-01

Privacy protection is an important issue and challenge in healthcare information systems (HISs). Recently, some privacy-enhanced HISs are proposed. Users' privacy perception, intention, and attitude might affect the adoption of such systems. This paper aims to propose a privacy-enhanced HIS framework and investigate the role of privacy protection in HISs adoption. In the proposed framework, privacy protection, access control, and secure transmission modules are designed to enhance the privacy protection of a HIS. An experimental privacy-enhanced HIS is also implemented. Furthermore, we proposed a research model extending the unified theory of acceptance and use of technology by considering perceived security and information security literacy and then investigate user adoption of a privacy-enhanced HIS. The experimental results and analyses showed that user adoption of a privacy-enhanced HIS is directly affected by social influence, performance expectancy, facilitating conditions, and perceived security. Perceived security has a mediating effect between information security literacy and user adoption. This study proposes several implications for research and practice to improve designing, development, and promotion of a good healthcare information system with privacy protection.

Utilizing a Trauma Systems Approach to Benchmark and Improve Combat Casualty Care

DTIC Science & Technology

2010-07-01

modern battlefield utilizing evidence - based medicine . The development of injury care benchmarks enhanced the evolution of the combat casualty care performance improvement process within the trauma system.

Miss-distance indicator for tank main guns

NASA Astrophysics Data System (ADS)

Bornstein, Jonathan A.; Hillis, David B.

1996-06-01

Tank main gun systems must possess extremely high levels of accuracy to perform successfully in battle. Under some circumstances, the first round fired in an engagement may miss the intended target, and it becomes necessary to rapidly correct fire. A breadboard automatic miss-distance indicator system was previously developed to assist in this process. The system, which would be mounted on a 'wingman' tank, consists of a charged-coupled device (CCD) camera and computer-based image-processing system, coupled with a separate infrared sensor to detect muzzle flash. For the system to be successfully employed with current generation tanks, it must be reliable, be relatively low cost, and respond rapidly maintaining current firing rates. Recently, the original indicator system was developed further in an effort to assist in achieving these goals. Efforts have focused primarily upon enhanced image-processing algorithms, both to improve system reliability and to reduce processing requirements. Intelligent application of newly refined trajectory models has permitted examination of reduced areas of interest and enhanced rejection of false alarms, significantly improving system performance.

Performance Enhancement of Radial Distributed System with Distributed Generators by Reconfiguration Using Binary Firefly Algorithm

NASA Astrophysics Data System (ADS)

Rajalakshmi, N.; Padma Subramanian, D.; Thamizhavel, K.

2015-03-01

The extent of real power loss and voltage deviation associated with overloaded feeders in radial distribution system can be reduced by reconfiguration. Reconfiguration is normally achieved by changing the open/closed state of tie/sectionalizing switches. Finding optimal switch combination is a complicated problem as there are many switching combinations possible in a distribution system. Hence optimization techniques are finding greater importance in reducing the complexity of reconfiguration problem. This paper presents the application of firefly algorithm (FA) for optimal reconfiguration of radial distribution system with distributed generators (DG). The algorithm is tested on IEEE 33 bus system installed with DGs and the results are compared with binary genetic algorithm. It is found that binary FA is more effective than binary genetic algorithm in achieving real power loss reduction and improving voltage profile and hence enhancing the performance of radial distribution system. Results are found to be optimum when DGs are added to the test system, which proved the impact of DGs on distribution system.

Healthtrak(tm): Technology Enhanced Human Interface to the Computerized Patient Record

DTIC Science & Technology

2002-07-01

and/or findings contained in this report are those of the author( s ) and should not be construed as an official Department of the Army position...34: Technology Enhanced Human Interface to the DAMDI17-02-C-0032 Computerized Patient Record 6. AUTHOR( S ) Azad M. Madni, Ph.D. Doctor Weiwen Lin Carla...C. Madni 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Intelligent Systems Technology, Incorporated

Foveal Processing Under Concurrent Peripheral Load in Profoundly Deaf Adults

PubMed Central

2016-01-01

Development of the visual system typically proceeds in concert with the development of audition. One result is that the visual system of profoundly deaf individuals differs from that of those with typical auditory systems. While past research has suggested deaf people have enhanced attention in the visual periphery, it is still unclear whether or not this enhancement entails deficits in central vision. Profoundly deaf and typically hearing adults were administered a variant of the useful field of view task that independently assessed performance on concurrent central and peripheral tasks. Identification of a foveated target was impaired by a concurrent selective peripheral attention task, more so in profoundly deaf adults than in the typically hearing. Previous findings of enhanced performance on the peripheral task were not replicated. These data are discussed in terms of flexible allocation of spatial attention targeted towards perceived task demands, and support a modified “division of labor” hypothesis whereby attentional resources co-opted to process peripheral space result in reduced resources in the central visual field. PMID:26657078

A novel computerized surgeon-machine interface for robot-assisted laser phonomicrosurgery.

PubMed

Mattos, Leonardo S; Deshpande, Nikhil; Barresi, Giacinto; Guastini, Luca; Peretti, Giorgio

2014-08-01

To introduce a novel computerized surgical system for improved usability, intuitiveness, accuracy, and controllability in robot-assisted laser phonomicrosurgery. Pilot technology assessment. The novel system was developed involving a newly designed motorized laser micromanipulator, a touch-screen display, and a graphics stylus. The system allows the control of a CO2 laser through interaction between the stylus and the live video of the surgical area. This empowers the stylus with the ability to have actual effect on the surgical site. Surgical enhancements afforded by this system were established through a pilot technology assessment using randomized trials comparing its performance with a state-of-the-art laser microsurgery system. Resident surgeons and medical students were chosen as subjects in performing sets of trajectory-following exercises. Image processing-based techniques were used for an objective performance assessment. A System Usability Scale-based questionnaire was used for the qualitative assessment. The computerized interface demonstrated superiority in usability, accuracy, and controllability over the state-of-the-art system. Significant ease of use and learning experienced by the subjects were demonstrated by the usability score assigned to the two compared interfaces: computerized interface = 83.96% versus state-of-the-art = 68.02%. The objective analysis showed a significant enhancement in accuracy and controllability: computerized interface = 90.02% versus state-of-the-art = 75.59%. The novel system significantly enhances the accuracy, usability, and controllability in laser phonomicrosurgery. The design provides an opportunity to improve the ergonomics and safety of current surgical setups. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Mass enhancement versus Stoner enhancement in strongly correlated metallic perovskites: LaNiO3 and LaCuO3

NASA Astrophysics Data System (ADS)

Zhou, J.-S.; Marshall, L. G.; Goodenough, J. B.

2014-06-01

Measurements of physical properties, including transport and magnetic properties, specific heat, and thermal conductivity, have been performed on high-quality samples of LaNiO3 and LaCuO3 synthesized under high pressure. Some measurements, such as thermoelectric power and magnetic susceptibility, have been made under high pressure. The availability of a complete set of data enables a side-by-side comparison between these two narrowband systems. We have demonstrated unambiguously the mass enhancement due to electron-electron correlations in both systems relative to the recent density functional theory results. Correlations in these narrowband systems also enhance the magnetic susceptibility. Ferromagnetic spin fluctuations give rise to a strong Stoner enhancement in the magnetic susceptibility in the quarter-filled LaNiO3. Although we are able to tune the bandwidth by either chemical substitutions or by applying hydrostatic pressure on LaNiO3, the Stoner enhancement does not lead to the Stoner instability.

Enhancing the Performance of Medical Implant Communication Systems through Cooperative Diversity

PubMed Central

Hegyi, Barnabás; Levendovszky, János

2010-01-01

Battery-operated medical implants—such as pacemakers or cardioverter-defibrillators—have already been widely used in practical telemedicine and telecare applications. However, no solution has yet been found to mitigate the effect of the fading that the in-body to off-body communication channel is subject to. In this paper, we reveal and assess the potential of cooperative diversity to combat fading—hence to improve system performance—in medical implant communication systems. In the particular cooperative communication scenario we consider, multiple cooperating receiver units are installed across the room accommodating the patient with a medical implant inside his/her body. Our investigations have shown that the application of cooperative diversity is a promising approach to enhance the performance of medical implant communication systems in various aspects such as implant lifetime and communication link reliability. PMID:20379346

Artificial Neural Identification and LMI Transformation for Model Reduction-Based Control of the Buck Switch-Mode Regulator

NASA Astrophysics Data System (ADS)

Al-Rabadi, Anas N.

2009-10-01

This research introduces a new method of intelligent control for the control of the Buck converter using newly developed small signal model of the pulse width modulation (PWM) switch. The new method uses supervised neural network to estimate certain parameters of the transformed system matrix [Ã]. Then, a numerical algorithm used in robust control called linear matrix inequality (LMI) optimization technique is used to determine the permutation matrix [P] so that a complete system transformation {[B˜], [C˜], [Ẽ]} is possible. The transformed model is then reduced using the method of singular perturbation, and state feedback control is applied to enhance system performance. The experimental results show that the new control methodology simplifies the model in the Buck converter and thus uses a simpler controller that produces the desired system response for performance enhancement.

Enhanced optical design by distortion control

NASA Astrophysics Data System (ADS)

Thibault, Simon; Gauvin, Jonny; Doucet, Michel; Wang, Min

2005-09-01

The control of optical distortion is useful for the design of a variety of optical system. The most popular is the F-theta lens used in laser scanning system to produce a constant scan velocity across the image plane. Many authors have designed during the last 20 years distortion control corrector. Today, many challenging digital imaging system can use distortion the enhanced their imaging capability. A well know example is a reversed telephoto type, if the barrel distortion is increased instead of being corrected; the result is a so-called Fish-eye lens. However, if we control the barrel distortion instead of only increasing it, the resulting system can have enhanced imaging capability. This paper will present some lens design and real system examples that clearly demonstrate how the distortion control can improve the system performances such as resolution. We present innovative optical system which increases the resolution in the field of view of interest to meet the needs of specific applications. One critical issue when we designed using distortion is the optimization management. Like most challenging lens design, the automatic optimization is less reliable. Proper management keeps the lens design within the correct range, which is critical for optimal performance (size, cost, manufacturability). Many lens design presented tailor a custom merit function and approach.

Systematic Self-Regulation of the Neural System Essential for Peak Performance and Wellbeing.

ERIC Educational Resources Information Center

Cassel, Russell N.

1985-01-01

Balance and harmony within one's neural system is dynamic and changing, and restoring that balance is essential for peak performance. With a minimum amount of training individuals are able to restore this delicate balance and thereby enhance their own wellbeing. Autogenic feedback training has been demonstrated to be an effective means for…

Mission Assessment of the Faraday Accelerator with Radio-frequency Assisted Discharge (FARAD)

NASA Technical Reports Server (NTRS)

Dankanich, John W.; Polzin, Kurt A.

2008-01-01

Pulsed inductive thrusters have typically been considered for future, high-power, missions requiring nuclear electric propulsion. These high-power systems, while promising equivalent or improved performance over state-of-the-art propulsion systems, presently have no planned missions for which they are well suited. The ability to efficiently operate an inductive thruster at lower energy and power levels may provide inductive thrusters near term applicability and mission pull. The Faraday Accelerator with Radio-frequency Assisted Discharge concept demonstrated potential for a high-efficiency, low-energy pulsed inductive thruster. The added benefits of energy recapture and/or pulse compression are shown to enhance the performance of the pulsed inductive propulsion system, yielding a system that con compete with and potentially outperform current state-of-the-art electric propulsion technologies. These enhancements lead to mission-level benefits associated with the use of a pulsed inductive thruster. Analyses of low-power near to mid-term missions and higher power far-term missions are undertaken to compare the performance of pulsed inductive thrusters with that delivered by state-of-the-art and development-level electric propulsion systems.

The athlete biological passport: ticket to a fair Commonwealth Games.

PubMed

Bucknall, Vittoria; Rehman, Haroon; Bassindale, Thomas; Clement, Rhys Ge

2014-08-01

In summer 2014, the world watched as Glasgow hosted the 2014 Commonwealth Games and athletes pushed the boundaries of human performance. Sport has developed into a multi-billion pound industry leading to the development of a 'win at any cost' mentality in some individuals. The abuse of performance-enhancing drugs has developed into a sophisticated arms race between those unfairly enhancing performance and those wishing to preserve the dignity of sport and the health of the competitors. The challenge for the Commonwealth games organising committee was to ensure that competition remained fair and that athletes were kept safe. The athlete biological passport is a system implemented by the World Anti-Doping Agency directed towards enhancing the identification of those athletes accountable for the misuse of performance-enhancing substances. This article exemplifies which drugs are currently being exploited and how the athlete biological passport has evolved to improve their detection. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Role of fin material and nanofluid in performance enhancement of automobile radiator

NASA Astrophysics Data System (ADS)

Jadar, Raju; Shashishekar, K. S.; Channa Keshava Naik, N.

2018-04-01

An effective cooling system can avoid engine and its components from overheating and helps in achieving optimum engine performance. This work deals with the fabrication and performance evaluation of an automobile radiator with i) Aluminum fins and ii) Al-MWCNT fins using 0.1 w/v% f-MWCNT nanofluid. F-MWCNT nanoparticles in the base fluid improves the rate of heat transfer in an automobile radiator integrated with Al-MWCNT fins. The enhancement of heat transfer mainly depends on the quantity of F-MWCNT nanoparticles added to the host fluid. During the study it was found that at a low weight by volume concentration of nanofluid the heat transfer enhancement of 8% was achieved using Al-MWCNT fins compared to base fluid.

Iris segmentation using an edge detector based on fuzzy sets theory and cellular learning automata.

PubMed

Ghanizadeh, Afshin; Abarghouei, Amir Atapour; Sinaie, Saman; Saad, Puteh; Shamsuddin, Siti Mariyam

2011-07-01

Iris-based biometric systems identify individuals based on the characteristics of their iris, since they are proven to remain unique for a long time. An iris recognition system includes four phases, the most important of which is preprocessing in which the iris segmentation is performed. The accuracy of an iris biometric system critically depends on the segmentation system. In this paper, an iris segmentation system using edge detection techniques and Hough transforms is presented. The newly proposed edge detection system enhances the performance of the segmentation in a way that it performs much more efficiently than the other conventional iris segmentation methods.

An assessment of a film enhancement system for use in a radiation therapy department.

PubMed

Solowsky, E L; Reinstein, L E; Meek, A G

1990-01-01

The clinical uses of a radiotherapy film enhancement system are explored. The primary functions of the system are to improve the quality of poorly exposed simulator and portal films, and to perform comparisons between the two films to determine whether patient or block positioning errors are present. Other features include: the production of inexpensive, high quality hardcopy images of simulation films and initial portal films for chart documentation, the capacity to overlay lateral simulation films with sagittal MRI films to aid in field design, and a mode to zoom in on individual CT or MRI images and enlarge them for video display during chart rounds or instructional sessions. This commercially available system is comprised of a microcomputer, frame grabber, CCD camera with zoom lens, and a high-resolution thermal printer. The user-friendly software is menu driven and utilizes both keyboard and track ball to perform its functions. At the heart of the software is a very fast Adaptive Histogram Equalization (AHE) routine, which enhances and improves the readability of most portal films. The system has been evaluated for several disease sites, and its advantages and limitations will be presented.

Live Yeast and Yeast Cell Wall Supplements Enhance Immune Function and Performance in Food-Producing Livestock: A Review †,‡

PubMed Central

Broadway, Paul R.; Carroll, Jeffery A.; Burdick Sanchez, Nicole C.

2015-01-01

More livestock producers are seeking natural alternatives to antibiotics and antimicrobials, and searching for supplements to enhance growth performance, and general animal health and well-being. Some of the compounds currently being utilized and studied are live yeast and yeast-based products derived from the strain Saccharomyces cerevisiae. These products have been reported to have positive effects both directly and indirectly on the immune system and its subsequent biomarkers, thereby mitigating negative effects associated with stress and disease. These yeast-based products have also been reported to simultaneously enhance growth and performance by enhancing dry matter intake (DMI) and average daily gain (ADG) perhaps through the establishment of a healthy gastrointestinal tract. These products may be especially useful in times of potential stress such as during birth, weaning, early lactation, and during the receiving period at the feedlot. Overall, yeast supplements appear to possess the ability to improve animal health and metabolism while decreasing morbidity, thereby enhancing profitability of these animals. PMID:27682097

Simulation-based evaluation of an in-vehicle smart situation awareness enhancement system.

PubMed

Gregoriades, Andreas; Sutcliffe, Alistair

2018-07-01

Situation awareness (SA) constitutes a critical factor in road safety, strongly related to accidents. This paper describes the evaluation of a proposed SA enhancement system (SAES) that exploits augmented reality through a head-up display (HUD). Two SAES designs were evaluation (information rich vs. minimal information) using a custom-made simulator and the Situation Awareness Global Assessment Technique with performance and EEG measures. The paper describes the process of assessing the SA of drivers using the SAES, through a series of experiments with participants in a Cave Automatic Virtual Environment. The effectiveness of the SAES was tested in a within-group research design. The results showed that the information rich (radar-style display) was superior to the minimal (arrow hazard indicator) design and that both SAES improved drivers' SA and performance compared to the control (no HUD) design. Practitioner Summary: Even though driver situation awareness is considered as one of the leading causes of road accidents, little has been done to enhance it. The current study demonstrates the positive effect of a proposed situation awareness enhancement system on driver situation awareness, through an experiment using virtual prototyping in a simulator.

Early experiences of endoscopic procedures in general surgery assisted by a computer-enhanced surgical system.

PubMed

Hashizume, M; Shimada, M; Tomikawa, M; Ikeda, Y; Takahashi, I; Abe, R; Koga, F; Gotoh, N; Konishi, K; Maehara, S; Sugimachi, K

2002-08-01

We performed a variety of complete total endoscopic general surgical procedures, including colon resection, distal gastrectomy, and splenectomy, successfully with the assistance of the da Vinci computer-enhanced surgical system. The robotic system allowed us to manipulate the endoscopic instruments as effectively as during open surgery. It enhanced visualization of both the operative field and precision of the necessary techniques, as well as being less stressful for the endoscopic operating team. This technological innovation can therefore help surgeons overcome many of the difficulties associated with the endoscopic approach and thus has the potential to enable more precise, safer, and more minimally invasive surgery in the future.

Going Boldly Beyond: Progress on NASA's Space Launch System

NASA Technical Reports Server (NTRS)

Singer, Jody; Crumbly, Chris

2013-01-01

NASA's Space Launch System is implementing an evolvable configuration approach to system development in a resource-constrained era. Legacy systems enable non-traditional development funding and contribute to sustainability and affordability. Limited simultaneous developments reduce cost and schedule risk. Phased approach to advanced booster development enables innovation and competition, incrementally demonstrating affordability and performance enhancements. Advanced boosters will provide performance for the most capable heavy lift launcher in history, enabling unprecedented space exploration benefiting all of humanity.

Performance measures to assess resiliency and efficiency of transit systems.

DOT National Transportation Integrated Search

2017-03-01

Transit agencies are interested in assessing the short-, mid-, and long-term performance of their infrastructure with the : objective of enhancing resiliency and efficiency. This report addresses three distinct aspects of New Jerseys Transit Syste...

A novel double loop control model design for chemical unstable processes.

PubMed

Cong, Er-Ding; Hu, Ming-Hui; Tu, Shan-Tung; Xuan, Fu-Zhen; Shao, Hui-He

2014-03-01

In this manuscript, based on Smith predictor control scheme for unstable process in industry, an improved double loop control model is proposed for chemical unstable processes. Inner loop is to stabilize integrating the unstable process and transform the original process to first-order plus pure dead-time dynamic stable process. Outer loop is to enhance the performance of set point response. Disturbance controller is designed to enhance the performance of disturbance response. The improved control system is simple with exact physical meaning. The characteristic equation is easy to realize stabilization. Three controllers are separately design in the improved scheme. It is easy to design each controller and good control performance for the respective closed-loop transfer function separately. The robust stability of the proposed control scheme is analyzed. Finally, case studies illustrate that the improved method can give better system performance than existing design methods. © 2013 ISA Published by ISA All rights reserved.

Modeling the Hydrologic Processes of a Permeable Pavement System

EPA Science Inventory

A permeable pavement system can capture stormwater to reduce runoff volume and flow rate, improve onsite groundwater recharge, and enhance pollutant controls within the site. A new unit process model for evaluating the hydrologic performance of a permeable pavement system has be...

Preliminary MIPCC Enhanced F-4 and F-15 Performance Characteristics for a First Stage Reusable Launch Vehicle

NASA Technical Reports Server (NTRS)

Kloesel, Kurt J.

2013-01-01

Performance increases in turbojet engines can theoretically be achieved through Mass Injection Pre-Compressor Cooling (MIPCC), a process involving injecting water or oxidizer or both into an afterburning turbojet engine. The injection of water results in pre-compressor cooling, allowing the propulsion system to operate at high altitudes and Mach numbers. In this way, a MIPCC-enhanced turbojet engine could be used to power the first stage of a reusable launch vehicle or be integrated into an existing aircraft that could launch a 100-lbm payload to a reference 100-nm altitude orbit at 28 deg inclination. The two possible candidates for MIPCC flight demonstration that are evaluated in this study are the F-4 Phantom II airplane and the F-15 Eagle airplane (both of McDonnell Douglas, now The Boeing Company, Chicago, Illinois), powered by two General Electric Company (Fairfield, Connecticut) J79 engines and two Pratt & Whitney (East Hartford, Connecticut) F100-PW-100 engines, respectively. This paper presents a conceptual discussion of the theoretical performance of each of these aircraft using MIPCC propulsion techniques. Trajectory studies were completed with the Optimal Trajectories by Implicit Simulation (OTIS) software (NASA Glenn Research Center, Cleveland, Ohio) for a standard F-4 airplane and a standard F-15 airplane. Standard aircraft simulation models were constructed, and the thrust in each was altered in accordance with estimated MIPCC performance characteristics. The MIPCC and production aircraft model results were then reviewed to assess the feasibility of a MIPCC-enhanced propulsion system for use as a first-stage reusable launch vehicle; it was determined that the MIPCC-enhanced F-15 model showed a significant performance advantage over the MIPCC-enhanced F-4 model.

The Effect of Online Systems Analysis Training on Aerospace Industry Business Performance: A Qualitative Study

ERIC Educational Resources Information Center

Burk, Erlan

2012-01-01

Aerospace companies needed additional research on technology-based training to verify expectations when enhancing human capital through online systems analysis training. The research for online systems analysis training provided aerospace companies a means to verify expectations for systems analysis technology-based training on business…

Multimedia Security System for Security and Medical Applications

ERIC Educational Resources Information Center

Zhou, Yicong

2010-01-01

This dissertation introduces a new multimedia security system for the performance of object recognition and multimedia encryption in security and medical applications. The system embeds an enhancement and multimedia encryption process into the traditional recognition system in order to improve the efficiency and accuracy of object detection and…

Charging and Discharging Processes of Thermal Energy Storage System Using Phase change materials

NASA Astrophysics Data System (ADS)

Kanimozhi, B., Dr.; Harish, Kasilanka; Sai Tarun, Bellamkonda; Saty Sainath Reddy, Pogaku; Sai Sujeeth, Padakandla

2017-05-01

The objective of the study is to investigate the thermal characteristics of charging and discharge processes of fabricated thermal energy storage system using Phase change materials. Experiments were performed with phase change materials in which a storage tank have designed and developed to enhance the heat transfer rate from the solar tank to the PCM storage tank. The enhancement of heat transfer can be done by using a number of copper tubes in the fabricated storage tank. This storage tank can hold or conserve heat energy for a much longer time than the conventional water storage system. Performance evaluations of experimental results during charging and discharging processes of paraffin wax have discussed. In which heat absorption and heat rejection have been calculated with various flow rate.

Improving control and estimation for distributed parameter systems utilizing mobile actuator-sensor network.

PubMed

Mu, Wenying; Cui, Baotong; Li, Wen; Jiang, Zhengxian

2014-07-01

This paper proposes a scheme for non-collocated moving actuating and sensing devices which is unitized for improving performance in distributed parameter systems. By Lyapunov stability theorem, each moving actuator/sensor agent velocity is obtained. To enhance state estimation of a spatially distributes process, two kinds of filters with consensus terms which penalize the disagreement of the estimates are considered. Both filters can result in the well-posedness of the collective dynamics of state errors and can converge to the plant state. Numerical simulations demonstrate that the effectiveness of such a moving actuator-sensor network in enhancing system performance and the consensus filters converge faster to the plant state when consensus terms are included. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Enhanced TCAS 2/CDTI traffic Sensor digital simulation model and program description

NASA Technical Reports Server (NTRS)

Goka, T.

1984-01-01

Digital simulation models of enhanced TCAS 2/CDTI traffic sensors are developed, based on actual or projected operational and performance characteristics. Two enhanced Traffic (or Threat) Alert and Collision Avoidance Systems are considered. A digital simulation program is developed in FORTRAN. The program contains an executive with a semireal time batch processing capability. The simulation program can be interfaced with other modules with a minimum requirement. Both the traffic sensor and CAS logic modules are validated by means of extensive simulation runs. Selected validation cases are discussed in detail, and capabilities and limitations of the actual and simulated systems are noted. The TCAS systems are not specifically intended for Cockpit Display of Traffic Information (CDTI) applications. These systems are sufficiently general to allow implementation of CDTI functions within the real systems' constraints.

Enhanced efficiency fertilizers: Effects on agronomic performance of corn in Iowa

USDA-ARS?s Scientific Manuscript database

Management of N in corn (Zea mays L.) production systems attempts to increase crop yields and minimize environment impact. This study evaluated enhanced efficiency fertilizers (EEFs) compared to their non-EEF forms on grain yield and corn biomass at the beginning of the grain-filling period, leaf ch...

Relationships between core factors of knowledge management in hospital nursing organisations and outcomes of nursing performance.

PubMed

Lee, Eun Ju; Kim, Hong Soon; Kim, Hye Young

2014-12-01

The study was conducted to investigate the levels of implementation of knowledge management and outcomes of nursing performance, to examine the relationships between core knowledge management factors and nursing performance outcomes and to identify core knowledge management factors affecting these outcomes. Effective knowledge management is very important to achieve strong organisational performance. The success or failure of knowledge management depends on how effectively an organisation's members share and use their knowledge. Because knowledge management plays a key role in enhancing nursing performance, identifying the core factors and investigating the level of knowledge management in a given hospital are priorities to ensure a high quality of nursing for patients. The study employed a descriptive research procedure. The study sample consisted of 192 nurses registered in three large healthcare organisations in South Korea. The variables demographic characteristics, implementation of core knowledge management factors and outcomes of nursing performance were examined and analysed in this study. The relationships between the core knowledge management factors and outcomes of nursing performance as well as the factors affecting the performance outcomes were investigated. A knowledge-sharing culture and organisational learning were found to be core factors affecting nursing performance. The study results provide basic data that can be used to formulate effective knowledge management strategies for enhancing nursing performance in hospital nursing organisations. In particular, prioritising the adoption of a knowledge-sharing culture and organisational learning in knowledge management systems might be one method for organisations to more effectively manage their knowledge resources and thus to enhance the outcomes of nursing performance and achieve greater business competitiveness. The study results can contribute to the development of effective and efficient knowledge management systems and strategies for enhancing knowledge-sharing culture and organisational learning that can improve both the productivity and competitiveness of healthcare organisations. © 2014 John Wiley & Sons Ltd.

Application and Evaluation of Control Modes for Risk-Based Engine Performance Enhancements

NASA Technical Reports Server (NTRS)

Liu, Yuan; Litt, Jonathan S.; Sowers, T. Shane; Owen, A. Karl (Compiler); Guo, Ten-Huei

2014-01-01

The engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the increased risk of failure. Accordingly, control modes were developed to improve the maximum thrust output and responsiveness of a generic high-bypass turbofan engine. The algorithms were designed such that the enhanced performance would always constitute an elevation in failure risk to a consistent predefined likelihood. This paper presents an application of these risk-based control modes to a combined engine/aircraft model. Through computer and piloted simulation tests, the aim is to present a notional implementation of these modes, evaluate their effects on a generic airframe, and demonstrate their usefulness during emergency flight situations. Results show that minimal control effort is required to compensate for the changes in flight dynamics due to control mode activation. The benefits gained from enhanced engine performance for various runway incursion scenarios are investigated. Finally, the control modes are shown to protect against potential instabilities during propulsion-only flight where all aircraft control surfaces are inoperable.

Whole body heat stress increases motor cortical excitability and skill acquisition in humans

PubMed Central

Littmann, Andrew E.; Shields, Richard K.

2015-01-01

Objective Vigorous systemic exercise stimulates a cascade of molecular and cellular processes that enhance central nervous system (CNS) plasticity and performance. The influence of heat stress on CNS performance and learning is novel. We designed two experiments to determine whether passive heat stress 1) facilitated motor cortex excitability and 2) improved motor task acquisition compared to no heat stress. Methods Motor evoked potentials (MEPs) from the first dorsal interosseus (FDI) were collected before and after 30 minutes of heat stress at 73° C. A second cohort of subjects performed a motor learning task using the FDI either following heat or the no heat condition. Results Heat stress increased heart rate to 65% of age-predicted maximum. After heat, mean resting MEP amplitude increased 48% (P < 0.05). MEP stimulus-response amplitudes did not differ according to stimulus intensity. In the second experiment, heat stress caused a significant decrease in absolute and variable error (p < 0.05) during a novel movement task using the FDI. Conclusions Passive environmental heat stress 1) increases motor cortical excitability, and 2) enhances performance in a motor skill acquisition task. Significance Controlled heat stress may prime the CNS to enhance motor skill acquisition during rehabilitation. PMID:26616546

Application and Evaluation of Control Modes for Risk-Based Engine Performance Enhancements

NASA Technical Reports Server (NTRS)

Liu, Yuan; Litt, Jonathan S.; Sowers, T. Shane; Owen, A. Karl; Guo, Ten-Huei

2015-01-01

The engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the increased risk of failure. Accordingly, control modes were developed to improve the maximum thrust output and responsiveness of a generic high-bypass turbofan engine. The algorithms were designed such that the enhanced performance would always constitute an elevation in failure risk to a consistent predefined likelihood. This paper presents an application of these risk-based control modes to a combined engine/aircraft model. Through computer and piloted simulation tests, the aim is to present a notional implementation of these modes, evaluate their effects on a generic airframe, and demonstrate their usefulness during emergency flight situations. Results show that minimal control effort is required to compensate for the changes in flight dynamics due to control mode activation. The benefits gained from enhanced engine performance for various runway incursion scenarios are investigated. Finally, the control modes are shown to protect against potential instabilities during propulsion-only flight where all aircraft control surfaces are inoperable.

Dynamic State Estimation for Multi-Machine Power System by Unscented Kalman Filter With Enhanced Numerical Stability

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

Qi, Junjian; Sun, Kai; Wang, Jianhui

In this paper, in order to enhance the numerical stability of the unscented Kalman filter (UKF) used for power system dynamic state estimation, a new UKF with guaranteed positive semidifinite estimation error covariance (UKFGPS) is proposed and compared with five existing approaches, including UKFschol, UKF-kappa, UKFmodified, UKF-Delta Q, and the squareroot UKF (SRUKF). These methods and the extended Kalman filter (EKF) are tested by performing dynamic state estimation on WSCC 3-machine 9-bus system and NPCC 48-machine 140-bus system. For WSCC system, all methods obtain good estimates. However, for NPCC system, both EKF and the classic UKF fail. It is foundmore » that UKFschol, UKF-kappa, and UKF-Delta Q do not work well in some estimations while UKFGPS works well in most cases. UKFmodified and SRUKF can always work well, indicating their better scalability mainly due to the enhanced numerical stability.« less

Investigation of self-adaptive LED surgical lighting based on entropy contrast enhancing method

NASA Astrophysics Data System (ADS)

Liu, Peng; Wang, Huihui; Zhang, Yaqin; Shen, Junfei; Wu, Rengmao; Zheng, Zhenrong; Li, Haifeng; Liu, Xu

2014-05-01

Investigation was performed to explore the possibility of enhancing contrast by varying the spectral distribution (SPD) of the surgical lighting. The illumination scenes with different SPDs were generated by the combination of a self-adaptive white light optimization method and the LED ceiling system, the images of biological sample are taken by a CCD camera and then processed by an 'Entropy' based contrast evaluation model which is proposed specific for surgery occasion. Compared with the neutral white LED based and traditional algorithm based image enhancing methods, the illumination based enhancing method turns out a better performance in contrast enhancing and improves the average contrast value about 9% and 6%, respectively. This low cost method is simple, practicable, and thus may provide an alternative solution for the expensive visual facility medical instruments.

Review on Applications of NanoFluids used in Vapour Compression Refrigeration System for Cop Enhancement

NASA Astrophysics Data System (ADS)

Veera Raghavalu, K.; Govindha Rasu, N.

2018-03-01

The present research paper focuses on the use of Nano additive refrigerants in vapor compression refrigeration system (VCRS) because of their amazing development during Thermo Physical along with heat transfer potential to improve the coefficient of performance (COP) and reliability of refrigeration system. Furthermore, challenges and future instructions of performance enhancement of VCRS using Nano additive refrigerants were presented. Lubricant oil is essential in the entire vapour compression refrigeration systems, mostly for the efficient function of the compressor. But, some assign of the oil is entire the cycle oil circulates with the refrigerant. Presently, an assortment of investigation is going on in the field of the Nano-particles like metals, oxides, carbon Nano-tubes or carbides. Nano-lubricants are unique type of Nano-fluids which are varieties of Nano-particles, lubricants and have a wide variety in the fields of refrigeration systems. This paper, has been done on the application of Nano-particles balanced in lubricating oils of refrigerating systems are reviewed. The aim of this investigation is to study and find which type of lubricant oil works better with Nano-particles in the area of refrigeration. From the review of literature, it has been observed that Nano-particles mixed with mineral oil gives enhanced results than polyolester (POE) oil.

Test bed experiments for various telerobotic system characteristics and configurations

NASA Technical Reports Server (NTRS)

Duffie, Neil A.; Wiker, Steven F.; Zik, John J.

1990-01-01

Dexterous manipulation and grasping in telerobotic systems depends on the integration of high-performance sensors, displays, actuators and controls into systems in which careful consideration has been given to human perception and tolerance. Research underway at the Wisconsin Center for Space Automation and Robotics (WCSAR) has the objective of enhancing the performance of these systems and their components, and quantifying the effects of the many electrical, mechanical, control, and human factors that affect their performance. This will lead to a fundamental understanding of performance issues which will in turn allow designers to evaluate sensor, actuator, display, and control technologies with respect to generic measures of dexterous performance. As part of this effort, an experimental test bed was developed which has telerobotic components with exceptionally high fidelity in master/slave operation. A Telerobotic Performance Analysis System has also been developed which allows performance to be determined for various system configurations and electro-mechanical characteristics. Both this performance analysis system and test bed experiments are described.

Study on Enhancement Principle and Stabilization for the Luminol-H2O2-HRP Chemiluminescence System

PubMed Central

Yang, Lihua; Jin, Maojun; Du, Pengfei; Chen, Ge; Zhang, Chan; Wang, Jian; Jin, Fen; Shao, Hua; She, Yongxin; Wang, Shanshan; Zheng, Lufei; Wang, Jing

2015-01-01

A luminol-H2O2-HRP chemiluminescence system with high relative luminescent intensity (RLU) and long stabilization time was investigated. First, the comparative study on the enhancement effect of ten compounds as enhancers to the luminol-H2O2-HRP chemiluminescence system was carried out, and the results showed that 4-(imidazol-1-yl)phenol (4-IMP), 4-iodophenol (4-IOP), 4-bromophenol (4-BOP) and 4-hydroxy-4’-iodobiphenyl (HIOP) had the best performance. Based on the experiment, the four enhancers were dissolved in acetone, acetonitrile, methanol, and dimethylformamide (DMF) with various concentrations, the results indicated that 4-IMP, 4-IOP, 4-BOP and HIOP dissolved in DMF with the concentrations of 0.2%, 3.2%, 1.6% and 3.2% could get the highest RLU values. Subsequently, the influences of pH, ionic strength, HRP, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol on the stabilization of the luminol-H2O2-HRP chemiluminescence system were studied, and we found that pH value, ionic strength, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol have little influence on luminescent stabilization, while HRP has a great influence. In different ranges of HRP concentration, different enhancers should be selected. When the concentration is within the range of 0~6 ng/mL, 4-IMP should be selected. When the concentration of HRP ranges from 6 to 25ng/mL, 4-IOP was the best choice. And when the concentration is within the range of 25~80 ng/mL, HIOP should be selected as the enhancer. Finally, the three well-performing chemiluminescent enhanced solutions (CESs) have been further optimized according to the three enhancers (4-IMP, 4-IOP and HIOP) in their utilized HRP concentration ranges. PMID:26154162

Study on Enhancement Principle and Stabilization for the Luminol-H2O2-HRP Chemiluminescence System.

PubMed

Yang, Lihua; Jin, Maojun; Du, Pengfei; Chen, Ge; Zhang, Chan; Wang, Jian; Jin, Fen; Shao, Hua; She, Yongxin; Wang, Shanshan; Zheng, Lufei; Wang, Jing

2015-01-01

A luminol-H2O2-HRP chemiluminescence system with high relative luminescent intensity (RLU) and long stabilization time was investigated. First, the comparative study on the enhancement effect of ten compounds as enhancers to the luminol-H2O2-HRP chemiluminescence system was carried out, and the results showed that 4-(imidazol-1-yl)phenol (4-IMP), 4-iodophenol (4-IOP), 4-bromophenol (4-BOP) and 4-hydroxy-4'-iodobiphenyl (HIOP) had the best performance. Based on the experiment, the four enhancers were dissolved in acetone, acetonitrile, methanol, and dimethylformamide (DMF) with various concentrations, the results indicated that 4-IMP, 4-IOP, 4-BOP and HIOP dissolved in DMF with the concentrations of 0.2%, 3.2%, 1.6% and 3.2% could get the highest RLU values. Subsequently, the influences of pH, ionic strength, HRP, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol on the stabilization of the luminol-H2O2-HRP chemiluminescence system were studied, and we found that pH value, ionic strength, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol have little influence on luminescent stabilization, while HRP has a great influence. In different ranges of HRP concentration, different enhancers should be selected. When the concentration is within the range of 0~6 ng/mL, 4-IMP should be selected. When the concentration of HRP ranges from 6 to 25 ng/mL, 4-IOP was the best choice. And when the concentration is within the range of 25~80 ng/mL, HIOP should be selected as the enhancer. Finally, the three well-performing chemiluminescent enhanced solutions (CESs) have been further optimized according to the three enhancers (4-IMP, 4-IOP and HIOP) in their utilized HRP concentration ranges.

Performance measures to assess resiliency and efficiency of transit systems [research brief].

DOT National Transportation Integrated Search

2017-03-01

Transit agencies, like other transportation agencies, are interested in assessing the short-, mid-, and long-term performance of their infrastructure with the objectives of making better decisions that will enhance resiliency and efficiency. This rep...

Radar tracking with an interacting multiple model and probabilistic data association filter for civil aviation applications.

PubMed

Jan, Shau-Shiun; Kao, Yu-Chun

2013-05-17

The current trend of the civil aviation technology is to modernize the legacy air traffic control (ATC) system that is mainly supported by many ground based navigation aids to be the new air traffic management (ATM) system that is enabled by global positioning system (GPS) technology. Due to the low receiving power of GPS signal, it is a major concern to aviation authorities that the operation of the ATM system might experience service interruption when the GPS signal is jammed by either intentional or unintentional radio-frequency interference. To maintain the normal operation of the ATM system during the period of GPS outage, the use of the current radar system is proposed in this paper. However, the tracking performance of the current radar system could not meet the required performance of the ATM system, and an enhanced tracking algorithm, the interacting multiple model and probabilistic data association filter (IMMPDAF), is therefore developed to support the navigation and surveillance services of the ATM system. The conventional radar tracking algorithm, the nearest neighbor Kalman filter (NNKF), is used as the baseline to evaluate the proposed radar tracking algorithm, and the real flight data is used to validate the IMMPDAF algorithm. As shown in the results, the proposed IMMPDAF algorithm could enhance the tracking performance of the current aviation radar system and meets the required performance of the new ATM system. Thus, the current radar system with the IMMPDAF algorithm could be used as an alternative system to continue aviation navigation and surveillance services of the ATM system during GPS outage periods.

Radar Tracking with an Interacting Multiple Model and Probabilistic Data Association Filter for Civil Aviation Applications

PubMed Central

Jan, Shau-Shiun; Kao, Yu-Chun

2013-01-01

The current trend of the civil aviation technology is to modernize the legacy air traffic control (ATC) system that is mainly supported by many ground based navigation aids to be the new air traffic management (ATM) system that is enabled by global positioning system (GPS) technology. Due to the low receiving power of GPS signal, it is a major concern to aviation authorities that the operation of the ATM system might experience service interruption when the GPS signal is jammed by either intentional or unintentional radio-frequency interference. To maintain the normal operation of the ATM system during the period of GPS outage, the use of the current radar system is proposed in this paper. However, the tracking performance of the current radar system could not meet the required performance of the ATM system, and an enhanced tracking algorithm, the interacting multiple model and probabilistic data association filter (IMMPDAF), is therefore developed to support the navigation and surveillance services of the ATM system. The conventional radar tracking algorithm, the nearest neighbor Kalman filter (NNKF), is used as the baseline to evaluate the proposed radar tracking algorithm, and the real flight data is used to validate the IMMPDAF algorithm. As shown in the results, the proposed IMMPDAF algorithm could enhance the tracking performance of the current aviation radar system and meets the required performance of the new ATM system. Thus, the current radar system with the IMMPDAF algorithm could be used as an alternative system to continue aviation navigation and surveillance services of the ATM system during GPS outage periods. PMID:23686142

AlliedSignal driver's viewer enhancement (DVE) for paramilitary and commercial applications

NASA Astrophysics Data System (ADS)

Emanuel, Michael; Caron, Hubert; Kovacevic, Branislav; Faina-Cherkaoui, Marcela; Wrobel, Leslie; Turcotte, Gilles

1999-07-01

AlliedSignal Driver's Viewer Enhancement (DVE) system is a thermal imager using a 320 X 240 uncooled microbolometer array. This high performance system was initially developed for military combat and tactical wheeled vehicles. It features a very small sensor head remotely mounted from the display, control and processing module. The sensor head has a modular design and is being adapted to various commercial applications such as truck and car-driving aid, using specifically designed low cost optics. Tradeoffs in the system design, system features and test results are discussed in this paper. A short video shows footage of the DVE system while driving at night.

Problem reporting management system performance simulation

NASA Technical Reports Server (NTRS)

Vannatta, David S.

1993-01-01

This paper proposes the Problem Reporting Management System (PRMS) model as an effective discrete simulation tool that determines the risks involved during the development phase of a Trouble Tracking Reporting Data Base replacement system. The model considers the type of equipment and networks which will be used in the replacement system as well as varying user loads, size of the database, and expected operational availability. The paper discusses the dynamics, stability, and application of the PRMS and addresses suggested concepts to enhance the service performance and enrich them.

Implementation and Performance of a GPS/INS Tightly Coupled Assisted PLL Architecture Using MEMS Inertial Sensors

PubMed Central

Tawk, Youssef; Tomé, Phillip; Botteron, Cyril; Stebler, Yannick; Farine, Pierre-André

2014-01-01

The use of global navigation satellite system receivers for navigation still presents many challenges in urban canyon and indoor environments, where satellite availability is typically reduced and received signals are attenuated. To improve the navigation performance in such environments, several enhancement methods can be implemented. For instance, external aid provided through coupling with other sensors has proven to contribute substantially to enhancing navigation performance and robustness. Within this context, coupling a very simple GPS receiver with an Inertial Navigation System (INS) based on low-cost micro-electro-mechanical systems (MEMS) inertial sensors is considered in this paper. In particular, we propose a GPS/INS Tightly Coupled Assisted PLL (TCAPLL) architecture, and present most of the associated challenges that need to be addressed when dealing with very-low-performance MEMS inertial sensors. In addition, we propose a data monitoring system in charge of checking the quality of the measurement flow in the architecture. The implementation of the TCAPLL is discussed in detail, and its performance under different scenarios is assessed. Finally, the architecture is evaluated through a test campaign using a vehicle that is driven in urban environments, with the purpose of highlighting the pros and cons of combining MEMS inertial sensors with GPS over GPS alone. PMID:24569773

Applications of nano and smart materials in renewable energy production and storage devices

NASA Astrophysics Data System (ADS)

Ghasemi-Nejhad, Mehrdad N.

2015-03-01

This paper presents development of renewable energy production and storage devices employing nanomaterials and smart materials. The use of carbon nanotubes (CNTs) and graphene nanosheets (GNS) to improve the performance and durability of wind turbine and wave rotor blades will be explained. While GNS are primary used for the performance enhancement of the resin system called Nanoresin, CNT Nanoforests and Nanofilms are used to improve the performance of fiber systems in high-performance Nanocomposites. In addition, the use of CNTs and piezo-nanofibers will be explained as the health monitoring and smart systems within the composites. A self-healing mechanism will also be explained within the composites using these materials. Next the use of CNTs as gas diffusion layers and CNTs combined with in-situ generated platinum nanoparticles as catalyst layers will be explained to improve the performance, efficiency, and durability of proton exchange membrane fuel cells while reducing their costs, weight, and size. In addition, the use of CNTs and GNSs to improve the efficiency and performance of polymer solar cells will be explained. Finally, the use of CNTs and GNSs to enhance the performance, efficiency, and durability of batteries and supercapacitors while reducing their costs, weight, and size will be discussed.

An application of the Multi-Purpose System Simulation /MPSS/ model to the Monitor and Control Display System /MACDS/ at the National Aeronautics and Space Administration /NASA/ Goddard Space Flight Center /GSFC/

NASA Technical Reports Server (NTRS)

Mill, F. W.; Krebs, G. N.; Strauss, E. S.

1976-01-01

The Multi-Purpose System Simulator (MPSS) model was used to investigate the current and projected performance of the Monitor and Control Display System (MACDS) at the Goddard Space Flight Center in processing and displaying launch data adequately. MACDS consists of two interconnected mini-computers with associated terminal input and display output equipment and a disk-stored data base. Three configurations of MACDS were evaluated via MPSS and their performances ascertained. First, the current version of MACDS was found inadequate to handle projected launch data loads because of unacceptable data backlogging. Second, the current MACDS hardware with enhanced software was capable of handling two times the anticipated data loads. Third, an up-graded hardware ensemble combined with the enhanced software was capable of handling four times the anticipated data loads.

Overview of the U.S. DOE Accident Tolerant Fuel Development Program

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

Jon Carmack; Frank Goldner; Shannon M. Bragg-Sitton

2013-09-01

The United States Fuel Cycle Research and Development Advanced Fuels Campaign has been given the responsibility to conduct research and development on enhanced accident tolerant fuels with the goal of performing a lead test assembly or lead test rod irradiation in a commercial reactor by 2022. The Advanced Fuels Campaign has defined fuels with enhanced accident tolerance as those that, in comparison with the standard UO2-Zircaloy system currently used by the nuclear industry, can tolerate loss of active cooling in the reactor core for a considerably longer time period (depending on the LWR system and accident scenario) while maintaining ormore » improving the fuel performance during normal operations and operational transients, as well as design-basis and beyond design-basis events. This paper provides an overview of the FCRD Accident Tolerant Fuel program. The ATF attributes will be presented and discussed. Attributes identified as potentially important to enhance accident tolerance include reduced hydrogen generation (resulting from cladding oxidation), enhanced fission product retention under severe accident conditions, reduced cladding reaction with high-temperature steam, and improved fuel-cladding interaction for enhanced performance under extreme conditions. To demonstrate the enhanced accident tolerance of candidate fuel designs, metrics must be developed and evaluated using a combination of design features for a given LWR design, potential improvements to that design, and the design of an advanced fuel/cladding system. The aforementioned attributes provide qualitative guidance for parameters that will be considered for fuels with enhanced accident tolerance. It may be unnecessary to improve in all attributes and it is likely that some attributes or combination of attributes provide meaningful gains in accident tolerance, while others may provide only marginal benefits. Thus, an initial step in program implementation will be the development of quantitative metrics. A companion paper in these proceedings provides an update on the status of establishing these quantitative metrics for accident tolerant LWR fuel.1 The United States FCRD Advanced Fuels Campaign has embarked on an aggressive schedule for development of enhanced accident tolerant LWR fuels. The goal of developing such a fuel system that can be deployed in the U.S. LWR fleet in the next 10 to 20 years supports the sustainability of clean nuclear power generation in the United States.« less

Development of task network models of human performance in microgravity

NASA Technical Reports Server (NTRS)

Diaz, Manuel F.; Adam, Susan

1992-01-01

This paper discusses the utility of task-network modeling for quantifying human performance variability in microgravity. The data are gathered for: (1) improving current methodologies for assessing human performance and workload in the operational space environment; (2) developing tools for assessing alternative system designs; and (3) developing an integrated set of methodologies for the evaluation of performance degradation during extended duration spaceflight. The evaluation entailed an analysis of the Remote Manipulator System payload-grapple task performed on many shuttle missions. Task-network modeling can be used as a tool for assessing and enhancing human performance in man-machine systems, particularly for modeling long-duration manned spaceflight. Task-network modeling can be directed toward improving system efficiency by increasing the understanding of basic capabilities of the human component in the system and the factors that influence these capabilities.

Final Project Report: Data Locality Enhancement of Dynamic Simulations for Exascale Computing

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

Shen, Xipeng

The goal of this project is to develop a set of techniques and software tools to enhance the matching between memory accesses in dynamic simulations and the prominent features of modern and future manycore systems, alleviating the memory performance issues for exascale computing. In the first three years, the PI and his group have achieves some significant progress towards the goal, producing a set of novel techniques for improving the memory performance and data locality in manycore systems, yielding 18 conference and workshop papers and 4 journal papers and graduating 6 Ph.Ds. This report summarizes the research results of thismore » project through that period.« less

High-precision radiometric tracking for planetary approach and encounter in the inner solar system

NASA Technical Reports Server (NTRS)

Christensen, C. S.; Thurman, S. W.; Davidson, J. M.; Finger, M. H.; Folkner, W. M.

1989-01-01

The benefits of improved radiometric tracking data have been studied for planetary approach within the inner Solar System using the Mars Rover Sample Return trajectory as a model. It was found that the benefit of improved data to approach and encounter navigation was highly dependent on the a priori uncertainties assumed for several non-estimated parameters, including those for frame-tie, Earth orientation, troposphere delay, and station locations. With these errors at their current levels, navigational performance was found to be insensitive to enhancements in data accuracy. However, when expected improvements in these errors are modeled, performance with current-accuracy data significantly improves, with substantial further improvements possible with enhancements in data accuracy.

Enhancing team-sport athlete performance: is altitude training relevant?

PubMed

Billaut, François; Gore, Christopher J; Aughey, Robert J

2012-09-01

Field-based team sport matches are composed of short, high-intensity efforts, interspersed with intervals of rest or submaximal exercise, repeated over a period of 60-120 minutes. Matches may also be played at moderate altitude where the lower oxygen partial pressure exerts a detrimental effect on performance. To enhance run-based performance, team-sport athletes use varied training strategies focusing on different aspects of team-sport physiology, including aerobic, sprint, repeated-sprint and resistance training. Interestingly, 'altitude' training (i.e. living and/or training in O(2)-reduced environments) has only been empirically employed by athletes and coaches to improve the basic characteristics of speed and endurance necessary to excel in team sports. Hypoxia, as an additional stimulus to training, is typically used by endurance athletes to enhance performance at sea level and to prepare for competition at altitude. Several approaches have evolved in the last few decades, which are known to enhance aerobic power and, thus, endurance performance. Altitude training can also promote an increased anaerobic fitness, and may enhance sprint capacity. Therefore, altitude training may confer potentially-beneficial adaptations to team-sport athletes, which have been overlooked in contemporary sport physiology research. Here, we review the current knowledge on the established benefits of altitude training on physiological systems relevant to team-sport performance, and conclude that current evidence supports implementation of altitude training modalities to enhance match physical performances at both sea level and altitude. We hope that this will guide the practice of many athletes and stimulate future research to better refine training programmes.

Performance Enhancement of MC-CDMA System through Novel Sensitive Bit Algorithm Aided Turbo Multi User Detection

PubMed Central

Kumaravel, Rasadurai; Narayanaswamy, Kumaratharan

2015-01-01

Multi carrier code division multiple access (MC-CDMA) system is a promising multi carrier modulation (MCM) technique for high data rate wireless communication over frequency selective fading channels. MC-CDMA system is a combination of code division multiple access (CDMA) and orthogonal frequency division multiplexing (OFDM). The OFDM parts reduce multipath fading and inter symbol interference (ISI) and the CDMA part increases spectrum utilization. Advantages of this technique are its robustness in case of multipath propagation and improve security with the minimize ISI. Nevertheless, due to the loss of orthogonality at the receiver in a mobile environment, the multiple access interference (MAI) appears. The MAI is one of the factors that degrade the bit error rate (BER) performance of MC-CDMA system. The multiuser detection (MUD) and turbo coding are the two dominant techniques for enhancing the performance of the MC-CDMA systems in terms of BER as a solution of overcome to MAI effects. In this paper a low complexity iterative soft sensitive bits algorithm (SBA) aided logarithmic-Maximum a-Posteriori algorithm (Log MAP) based turbo MUD is proposed. Simulation results show that the proposed method provides better BER performance with low complexity decoding, by mitigating the detrimental effects of MAI. PMID:25714917

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

Metal-air cell with performance enhancing additive

DOEpatents

Friesen, Cody A; Buttry, Daniel

2015-11-10

Systems and methods drawn to an electrochemical cell comprising a low temperature ionic liquid comprising positive ions and negative ions and a performance enhancing additive added to the low temperature ionic liquid. The additive dissolves in the ionic liquid to form cations, which are coordinated with one or more negative ions forming ion complexes. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. The ion complexes improve oxygen reduction thermodynamics and/or kinetics relative to the ionic liquid without the additive.

Advanced Fuels Campaign FY 2015 Accomplishments Report

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

Braase, Lori Ann; Carmack, William Jonathan

2015-10-29

The mission of the Advanced Fuels Campaign (AFC) is to perform research, development, and demonstration (RD&D) activities for advanced fuel forms (including cladding) to enhance the performance and safety of the nation’s current and future reactors; enhance proliferation resistance of nuclear fuel; effectively utilize nuclear energy resources; and address the longer-term waste management challenges. This report is a compilation of technical accomplishment summaries for FY-15. Emphasis is on advanced accident-tolerant LWR fuel systems, advanced transmutation fuels technologies, and capability development.

Performance Enhancement by Threshold Level Control of a Receiver in WDM-PON System with Manchester Coded Downstream and NRZ Upstream Re-Modulation

NASA Astrophysics Data System (ADS)

Kim, Bong Kyu; Chung, Hwan Seok; Chang, Sun Hyok; Park, Sangjo

We propose and demonstrate a scheme enhancing the performance of optical access networks with Manchester coded downstream and re-modulated NRZ coded upstream. It is achieved by threshold level control of a limiting amplifier at a receiver, and the minimum sensitivity of upstream is significantly improved for the re-modulation scheme with 5Gb/s Manchester coded downstream and 2.488Gb/s NRZ upstream data rates.

Enhanced aerobic degradation of 4-chlorophenol with iron-nickel nanoparticles

NASA Astrophysics Data System (ADS)

Shen, Wenjuan; Mu, Yi; Wang, Bingning; Ai, Zhihui; Zhang, Lizhi

2017-01-01

In this study, we demonstrate that the bimetallic iron-nickel nanoparticles (nZVIN) possessed an enhanced performance in comparison with nanoscale zero-valent iron (nZVI) on aerobic degradation of 4-chlorophenol (4-CP). The 4-CP degradation rate constant in the aerobic nZVIN process (nZVIN/Air) was 5 times that in the classic nZVI counterpart system (nZVI/Air). Both reactive oxygen species measurement and inhibition experimental results suggested that hydroxyl radicals were the major active species contributed to aerobic 4-CP degradation with nZVI, on contrast, superoxide radicals predominated the 4-CP degradation in the nZVIN/Air process. High performance liquid chromatography and gas chromatography-mass spectrometer analysis indicated the intermediates of the nZVI/Air system were p-benzoquinone and hydroquinone, which were resulted from the bond cleavage between the chlorine and carbon atom in the benzene ring by hydroxyl radicals. However, the primary intermediates of 4-CP found in the nZVIN/Air system were phenol via the direct dechlorination by superoxide radicals, accompanying with the formation of chloride ions. On the base of experimental results, a superoxide radicals mediated enhancing mechanism was proposed for the aerobic degradation of 4-CP in the nZVIN/Air system. This study provides new insight into the role of bimetallic nickel on enhancing removal of organic pollutants with nZVI.

Polyethersulfone - barium chloride blend ultrafiltration membranes for dye removal studies

NASA Astrophysics Data System (ADS)

Rambabu, K.; Srivatsan, N.; Gurumoorthy, Anand V. P.

2017-11-01

A series of Polyethersulfone (PES) - barium chloride (BaCl2) blend ultra filtration membrane was developed by varying the BaCl2 concentration in the dope solution. Prepared membranes were subjected to membrane characterization and their performance was studied through dye rejection tests. Morphological studies through SEM and AFM showed that the composite membranes exhibited differences in morphologies, porosities and properties due to the BaCl2 addition as compared with pristine PES membrane. Addition of the inorganic modifier enhanced the hydrophilicity and water permeability of the blend membrane system. Polymer enhanced ultrafiltration of dye solutions showed that the proposed blend system had better performance in terms of flux and rejection efficiency than the pure polymer membrane. The performance of the 2 wt% BaCl2 blend membrane was more promising for application to real time dye wastewater studies.

Computer-enhanced laparoscopic training system (CELTS): bridging the gap.

PubMed

Stylopoulos, N; Cotin, S; Maithel, S K; Ottensmeye, M; Jackson, P G; Bardsley, R S; Neumann, P F; Rattner, D W; Dawson, S L

2004-05-01

There is a large and growing gap between the need for better surgical training methodologies and the systems currently available for such training. In an effort to bridge this gap and overcome the disadvantages of the training simulators now in use, we developed the Computer-Enhanced Laparoscopic Training System (CELTS). CELTS is a computer-based system capable of tracking the motion of laparoscopic instruments and providing feedback about performance in real time. CELTS consists of a mechanical interface, a customizable set of tasks, and an Internet-based software interface. The special cognitive and psychomotor skills a laparoscopic surgeon should master were explicitly defined and transformed into quantitative metrics based on kinematics analysis theory. A single global standardized and task-independent scoring system utilizing a z-score statistic was developed. Validation exercises were performed. The scoring system clearly revealed a gap between experts and trainees, irrespective of the task performed; none of the trainees obtained a score above the threshold that distinguishes the two groups. Moreover, CELTS provided educational feedback by identifying the key factors that contributed to the overall score. Among the defined metrics, depth perception, smoothness of motion, instrument orientation, and the outcome of the task are major indicators of performance and key parameters that distinguish experts from trainees. Time and path length alone, which are the most commonly used metrics in currently available systems, are not considered good indicators of performance. CELTS is a novel and standardized skills trainer that combines the advantages of computer simulation with the features of the traditional and popular training boxes. CELTS can easily be used with a wide array of tasks and ensures comparability across different training conditions. This report further shows that a set of appropriate and clinically relevant performance metrics can be defined and a standardized scoring system can be designed.

40 CFR 141.718 - Treatment performance toolbox components.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for.... (a) Combined filter performance. Systems using conventional filtration treatment or direct filtration... the criteria in this paragraph. Combined filter effluent (CFE) turbidity must be less than or equal to...

40 CFR 141.718 - Treatment performance toolbox components.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for.... (a) Combined filter performance. Systems using conventional filtration treatment or direct filtration... the criteria in this paragraph. Combined filter effluent (CFE) turbidity must be less than or equal to...

40 CFR 141.718 - Treatment performance toolbox components.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for.... (a) Combined filter performance. Systems using conventional filtration treatment or direct filtration... the criteria in this paragraph. Combined filter effluent (CFE) turbidity must be less than or equal to...

77 FR 58814 - Privacy Act of 1974 System of Records Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-24

... revises the description of the system and enhancements to more broadly cover the Commission's market oversight, and market, risk and financial surveillance activities. The data covered by this expanded system includes records required to monitor the commodity futures and swaps markets, perform various mission...

75 FR 77305 - Security-Based Swap Data Repository Registration, Duties, and Core Principles

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-10

... authorities can access and analyze the data from secure, central locations to better monitor for systemic risk... authorities information to help limit systemic risk and by promoting stability through enhanced transparency...) performing market surveillance, prudential supervision, and macroprudential (systemic risk) supervision; and...

Evaluation of a prospective scoring system designed for a multicenter breast MR imaging screening study.

PubMed

Warren, Ruth M L; Thompson, Deborah; Pointon, Linda J; Hoff, Rebecca; Gilbert, Fiona J; Padhani, Anwar R; Easton, Douglas F; Lakhani, Sunil R; Leach, Martin O

2006-06-01

To evaluate prospectively the accuracy of a lesion classification system designed for use in a magnetic resonance (MR) imaging high-breast-cancer-risk screening study. All participating patients provided written informed consent. Ethics committee approval was obtained. The results of 1541 contrast material-enhanced breast MR imaging examinations were analyzed; 1441 screening examinations were performed in 638 women aged 24-51 years at high risk for breast cancer, and 100 examinations were performed in 100 women aged 23-81 years. Lesion analysis was performed in 991 breasts, which were divided into design (491 breasts) and testing (500 breasts) sets. The reference standard was histologic analysis of biopsy samples, fine-needle aspiration cytology, or minimal follow-up of 24 months. The scoring system involved the use of five features: morphology (MOR), pattern of enhancement (POE), percentage of maximal focal enhancement (PMFE), maximal signal intensity-time ratio (MITR), and pattern of contrast material washout (POCW). The system was evaluated by means of (a) assessment of interreader agreement, as expressed in kappa statistics, for 315 breasts in which both readers analyzed the same lesion, (b) assessment of the diagnostic accuracy of the scored components with receiver operating characteristic curve analysis, and (c) logistic regression analysis to determine which components of the scoring system were critical to the final score. A new simplified scoring system developed with the design set was applied to the testing set. There was moderate reader agreement regarding overall lesion outcome (ie, malignant, suspicious, or benign) (kappa=0.58) and less agreement regarding the scored components. The area under the receiver operating characteristic curve (AUC) for the overall lesion score, 0.88, was higher than the AUC for any one component. The components MOR, POE, and POCW yielded the best overall result. PMFE and MITR did not contribute to diagnostic utility. Applying a simplified scoring system to the testing set yielded a nonsignificantly (P=.2) higher AUC than did applying the original scoring system (sensitivity, 84%; specificity, 86.0%). Good diagnostic accuracy can be achieved by using simple qualitative descriptors of lesion enhancement, including POCW. In the context of screening, quantitative enhancement parameters appear to be less useful for lesion characterization. Copyright (c) RSNA, 2006.

Efficient Residue to Binary Conversion Based on a Modified Flexible Moduli Set

NASA Astrophysics Data System (ADS)

Molahosseini, Amir Sabbagh

2011-09-01

The Residue Number System (RNS) is a non-weighted number system which can perform addition (subtraction) and multiplication on residues without carry-propagation; resulting in high-speed hardware implementations of computation systems. The problem of converting residue numbers to equivalent binary weighted form has been attracted a lot of research for many years. Recently, some researchers proposed using flexible moduli sets instead of previous traditional moduli sets to enhance the performance of residue to binary converters. This paper introduces the modified flexible moduli set {22p+k. 22p+1, 2p+1, 2p-1} which is achieved from the flexible set {2p+k, 22p+1, 2p+1, 2p-1} by enhancing modulo 2p+k. Next, new Chinese remainder theorem-1 is used to design simple and efficient residue to binary converter for this modified set with better performance than the converter of the moduli set {2p+k, 22p+1, 2p+1, 2p-1}.

New functional biocarriers for enhancing the performance of a hybrid moving bed biofilm reactor-membrane bioreactor system.

PubMed

Deng, Lijuan; Guo, Wenshan; Ngo, Huu Hao; Zhang, Xinbo; Wang, Xiaochang C; Zhang, Qionghua; Chen, Rong

2016-05-01

In this study, new sponge modified plastic carriers for moving bed biofilm reactor (MBBR) was developed. The performance and membrane fouling behavior of a hybrid MBBR-membrane bioreactor (MBBR-MBR) system were also evaluated. Comparing to the MBBR with plastic carriers (MBBR), the MBBR with sponge modified biocarriers (S-MBBR) showed better effluent quality and enhanced nutrient removal at HRTs of 12h and 6h. Regarding fouling issue of the hybrid systems, soluble microbial products (SMP) of the MBR unit greatly influenced membrane fouling. The sponge modified biocarriers could lower the levels of SMP in mixed liquor and extracellular polymeric substances in activated sludge, thereby mitigating cake layer and pore blocking resistances of the membrane. The reduced SMP and biopolymer clusters in membrane cake layer were also observed. The results demonstrated that the sponge modified biocarriers were capable of improving overall MBBR performance and substantially alleviated membrane fouling of the subsequent MBR unit. Copyright © 2016 Elsevier Ltd. All rights reserved.

Demonstrating real-time feedback that enhances the performance of measurement sequence with cat states in a cavity

NASA Astrophysics Data System (ADS)

Ofek, N.; Petrenko, A.; Liu, Y.; Vlastakis, B.; Sun, L.; Leghtas, Z.; Heeres, R.; Sliwa, K. M.; Mirrahimi, M.; Jiang, L.; Devoret, M. H.; Schoelkopf, R. J.

2015-03-01

Real-time feedback offers not just the convenience of streamlined data acquisition, but is an essential element in any quantum computational architecture that requires branching based on measurement outcomes. State-preparation, mitigating the effects of qubit decoherence, and recording the trajectories of quantum systems are just a few of the many potential applications of real-time feedback. Photon number parity measurements of cat states in superconducting resonators are a particularly useful platform for demonstrating the clear advantages of having sophisticated feedback schemes to enhance the performance a proposed error-correction protocol [Leghtas et.al. PRL 2013]. In a cQED architecture, where a transmon qubit is coupled to two superconducting cavities, we present a field-programmable gate array (FPGA) device capable of making decisions and calculations with latency times far shorter than the lifetimes of any of the system's constituents. This level of performance opens the door to realizing many complex, previously unfeasible, experiments in superconducting qubit systems.

Development of new two-dimensional spectral/spatial code based on dynamic cyclic shift code for OCDMA system

NASA Astrophysics Data System (ADS)

Jellali, Nabiha; Najjar, Monia; Ferchichi, Moez; Rezig, Houria

2017-07-01

In this paper, a new two-dimensional spectral/spatial codes family, named two dimensional dynamic cyclic shift codes (2D-DCS) is introduced. The 2D-DCS codes are derived from the dynamic cyclic shift code for the spectral and spatial coding. The proposed system can fully eliminate the multiple access interference (MAI) by using the MAI cancellation property. The effect of shot noise, phase-induced intensity noise and thermal noise are used to analyze the code performance. In comparison with existing two dimensional (2D) codes, such as 2D perfect difference (2D-PD), 2D Extended Enhanced Double Weight (2D-Extended-EDW) and 2D hybrid (2D-FCC/MDW) codes, the numerical results show that our proposed codes have the best performance. By keeping the same code length and increasing the spatial code, the performance of our 2D-DCS system is enhanced: it provides higher data rates while using lower transmitted power and a smaller spectral width.

Acoustic Test Characterization of Melamine Foam for Usage in NASA's Payload Fairing Acoustic Attenuation Systems

NASA Technical Reports Server (NTRS)

Hughes, William O.; McNelis, Anne M.; McNelis, Mark E.

2014-01-01

The external acoustic liftoff levels predicted for NASA's future heavy lift launch vehicles are expected to be significantly higher than the environment created by today's commercial launch vehicles. This creates a need to develop an improved acoustic attenuation system for future NASA payload fairings. NASA Glenn Research Center initiated an acoustic test series to characterize the acoustic performance of melamine foam, with and without various acoustic enhancements. This testing was denoted as NEMFAT, which stands for NESC Enhanced Melamine Foam Acoustic Test, and is the subject of this paper. Both absorption and transmission loss testing of numerous foam configurations were performed at the Riverbank Acoustical Laboratory in July 2013. The NEMFAT test data provides an initial acoustic characterization and database of melamine foam for NASA. Because of its acoustic performance and lighter mass relative to fiberglass blankets, melamine foam is being strongly considered for use in the acoustic attenuation systems of NASA's future launch vehicles.

Performance Evaluation of a Data Validation System

NASA Technical Reports Server (NTRS)

Wong, Edmond (Technical Monitor); Sowers, T. Shane; Santi, L. Michael; Bickford, Randall L.

2005-01-01

Online data validation is a performance-enhancing component of modern control and health management systems. It is essential that performance of the data validation system be verified prior to its use in a control and health management system. A new Data Qualification and Validation (DQV) Test-bed application was developed to provide a systematic test environment for this performance verification. The DQV Test-bed was used to evaluate a model-based data validation package known as the Data Quality Validation Studio (DQVS). DQVS was employed as the primary data validation component of a rocket engine health management (EHM) system developed under NASA's NGLT (Next Generation Launch Technology) program. In this paper, the DQVS and DQV Test-bed software applications are described, and the DQV Test-bed verification procedure for this EHM system application is presented. Test-bed results are summarized and implications for EHM system performance improvements are discussed.

Invasive Species Forecasting System: A Decision Support Tool for the U.S. Geological Survey: FY 2005 Benchmarking Report v.1.6

NASA Technical Reports Server (NTRS)

Stohlgren, Tom; Schnase, John; Morisette, Jeffrey; Most, Neal; Sheffner, Ed; Hutchinson, Charles; Drake, Sam; Van Leeuwen, Willem; Kaupp, Verne

2005-01-01

The National Institute of Invasive Species Science (NIISS), through collaboration with NASA's Goddard Space Flight Center (GSFC), recently began incorporating NASA observations and predictive modeling tools to fulfill its mission. These enhancements, labeled collectively as the Invasive Species Forecasting System (ISFS), are now in place in the NIISS in their initial state (V1.0). The ISFS is the primary decision support tool of the NIISS for the management and control of invasive species on Department of Interior and adjacent lands. The ISFS is the backbone for a unique information services line-of-business for the NIISS, and it provides the means for delivering advanced decision support capabilities to a wide range of management applications. This report describes the operational characteristics of the ISFS, a decision support tool of the United States Geological Survey (USGS). Recent enhancements to the performance of the ISFS, attained through the integration of observations, models, and systems engineering from the NASA are benchmarked; i.e., described quantitatively and evaluated in relation to the performance of the USGS system before incorporation of the NASA enhancements. This report benchmarks Version 1.0 of the ISFS.

Providing haptic feedback in robot-assisted minimally invasive surgery: a direct optical force-sensing solution for haptic rendering of deformable bodies.

PubMed

Ehrampoosh, Shervin; Dave, Mohit; Kia, Michael A; Rablau, Corneliu; Zadeh, Mehrdad H

2013-01-01

This paper presents an enhanced haptic-enabled master-slave teleoperation system which can be used to provide force feedback to surgeons in minimally invasive surgery (MIS). One of the research goals was to develop a combined-control architecture framework that included both direct force reflection (DFR) and position-error-based (PEB) control strategies. To achieve this goal, it was essential to measure accurately the direct contact forces between deformable bodies and a robotic tool tip. To measure the forces at a surgical tool tip and enhance the performance of the teleoperation system, an optical force sensor was designed, prototyped, and added to a robot manipulator. The enhanced teleoperation architecture was formulated by developing mathematical models for the optical force sensor, the extended slave robot manipulator, and the combined-control strategy. Human factor studies were also conducted to (a) examine experimentally the performance of the enhanced teleoperation system with the optical force sensor, and (b) study human haptic perception during the identification of remote object deformability. The first experiment was carried out to discriminate deformability of objects when human subjects were in direct contact with deformable objects by means of a laparoscopic tool. The control parameters were then tuned based on the results of this experiment using a gain-scheduling method. The second experiment was conducted to study the effectiveness of the force feedback provided through the enhanced teleoperation system. The results show that the force feedback increased the ability of subjects to correctly identify materials of different deformable types. In addition, the virtual force feedback provided by the teleoperation system comes close to the real force feedback experienced in direct MIS. The experimental results provide design guidelines for choosing and validating the control architecture and the optical force sensor.

Combined peak-to-average power ratio reduction and physical layer security enhancement in optical orthogonal frequency division multiplexing visible-light communication systems

NASA Astrophysics Data System (ADS)

Wang, Zhongpeng; Chen, Shoufa

2016-07-01

A physical encryption scheme for discrete Hartley transform (DHT) precoded orthogonal frequency division multiplexing (OFDM) visible-light communication (VLC) systems using frequency domain chaos scrambling is proposed. In the scheme, the chaos scrambling, which is generated by a modified logistic mapping, is utilized to enhance the physical layer of security, and the DHT precoding is employed to reduce of OFDM signal for OFDM-based VLC. The influence of chaos scrambling on peak-to-average power ratio (PAPR) and bit error rate (BER) of systems is studied. The experimental simulation results prove the efficiency of the proposed encryption method for DHT-precoded, OFDM-based VLC systems. Furthermore, the influence of the proposed encryption to the PAPR and BER of systems is evaluated. The experimental results show that the proposed security scheme can protect the DHT-precoded, OFDM-based VLC from eavesdroppers, while keeping the good BER performance of DHT-precoded systems. The BER performance of the encrypted and DHT-precoded system is almost the same as that of the conventional DHT-precoded system without encryption.

Tightly-Coupled Integration of Multi-GNSS Single-Frequency RTK and MEMS-IMU for Enhanced Positioning Performance

PubMed Central

Li, Tuan; Zhang, Hongping; Niu, Xiaoji; Gao, Zhouzheng

2017-01-01

Dual-frequency Global Positioning System (GPS) Real-time Kinematics (RTK) has been proven in the past few years to be a reliable and efficient technique to obtain high accuracy positioning. However, there are still challenges for GPS single-frequency RTK, such as low reliability and ambiguity resolution (AR) success rate, especially in kinematic environments. Recently, multi-Global Navigation Satellite System (multi-GNSS) has been applied to enhance the RTK performance in terms of availability and reliability of AR. In order to further enhance the multi-GNSS single-frequency RTK performance in terms of reliability, continuity and accuracy, a low-cost micro-electro-mechanical system (MEMS) inertial measurement unit (IMU) is adopted in this contribution. We tightly integrate the single-frequency GPS/BeiDou/GLONASS and MEMS-IMU through the extended Kalman filter (EKF), which directly fuses the ambiguity-fixed double-differenced (DD) carrier phase observables and IMU data. A field vehicular test was carried out to evaluate the impacts of the multi-GNSS and IMU on the AR and positioning performance in different system configurations. Test results indicate that the empirical success rate of single-epoch AR for the tightly-coupled single-frequency multi-GNSS RTK/INS integration is over 99% even at an elevation cut-off angle of 40°, and the corresponding position time series is much more stable in comparison with the GPS solution. Besides, GNSS outage simulations show that continuous positioning with certain accuracy is possible due to the INS bridging capability when GNSS positioning is not available. PMID:29077070

Tightly-Coupled Integration of Multi-GNSS Single-Frequency RTK and MEMS-IMU for Enhanced Positioning Performance.

PubMed

Li, Tuan; Zhang, Hongping; Niu, Xiaoji; Gao, Zhouzheng

2017-10-27

Dual-frequency Global Positioning System (GPS) Real-time Kinematics (RTK) has been proven in the past few years to be a reliable and efficient technique to obtain high accuracy positioning. However, there are still challenges for GPS single-frequency RTK, such as low reliability and ambiguity resolution (AR) success rate, especially in kinematic environments. Recently, multi-Global Navigation Satellite System (multi-GNSS) has been applied to enhance the RTK performance in terms of availability and reliability of AR. In order to further enhance the multi-GNSS single-frequency RTK performance in terms of reliability, continuity and accuracy, a low-cost micro-electro-mechanical system (MEMS) inertial measurement unit (IMU) is adopted in this contribution. We tightly integrate the single-frequency GPS/BeiDou/GLONASS and MEMS-IMU through the extended Kalman filter (EKF), which directly fuses the ambiguity-fixed double-differenced (DD) carrier phase observables and IMU data. A field vehicular test was carried out to evaluate the impacts of the multi-GNSS and IMU on the AR and positioning performance in different system configurations. Test results indicate that the empirical success rate of single-epoch AR for the tightly-coupled single-frequency multi-GNSS RTK/INS integration is over 99% even at an elevation cut-off angle of 40°, and the corresponding position time series is much more stable in comparison with the GPS solution. Besides, GNSS outage simulations show that continuous positioning with certain accuracy is possible due to the INS bridging capability when GNSS positioning is not available.

Flexible photonic payload for broadband telecom satellites: from concepts to system demonstrators

NASA Astrophysics Data System (ADS)

Sotom, M.; Aveline, M.; Barbaste, R.; Benazet, B.; Le Kernec, A.; Magnaval, J.; Picq, M.

2017-09-01

In the last decade, Thales Alenia Space has put significant research effort in photonic technologies for satellite applications, with the objective to provide telecom payload systems with enhanced functionality, higher performance and lower costs.

Raman-based system for DNA sequencing-mapping and other separations

DOEpatents

Vo-Dinh, Tuan

1994-01-01

DNA sequencing and mapping are performed by using a Raman spectrometer with a surface enhanced Raman scattering (SERS) substrate to enhance the Raman signal. A SERS label is attached to a DNA fragment and then analyzed with the Raman spectrometer to identify the DNA fragment according to characteristics of the Raman spectrum generated.

ETV, LT2 and You: How the Environmental Technology Verification Program Can Assist with the Long Term 2 Enhanced Surface Water Treatment Rule

EPA Science Inventory

The Environmental Technology Verification (ETV) Drinking Water Systems (DWS) Center has verified the performance of treatment technologies that may be used by communities in meeting the newly promulgated (2006) U.S. Environmental Protection Agency (USEPA) Long Term 2 Enhanced Sur...

A novel method for real-time edge-enhancement and its application to pattern recognition

NASA Astrophysics Data System (ADS)

Ge, Huayong; Bai, Enjian; Fan, Hong

2010-11-01

The coupling gain coefficient g is redefined and deduced based on coupling theory, the variant of coupling gain coefficient g for different ΓL and r is analyzed. A new optical system is proposed for image edge-enhancement. It recycles the back signal to amplify the edge signal, which has the advantages of high throughput efficiency and brightness. The optical system is designed and built, and the edge-enhanced image of hand bone is captured electronically by CCD camera. The principle of optical correlation is demonstrated, 3-D correlation distribution of letter H with and without edge-enhancement is simulated, the discrimination capability Iac and the full-width at half maximum intensity (FWHM) are compared for two kinds of correlators. The analysis shows that edge-enhancement preprocessing can improve the performance of correlator effectively.

[A modified speech enhancement algorithm for electronic cochlear implant and its digital signal processing realization].

PubMed

Wang, Yulin; Tian, Xuelong

2014-08-01

In order to improve the speech quality and auditory perceptiveness of electronic cochlear implant under strong noise background, a speech enhancement system used for electronic cochlear implant front-end was constructed. Taking digital signal processing (DSP) as the core, the system combines its multi-channel buffered serial port (McBSP) data transmission channel with extended audio interface chip TLV320AIC10, so speech signal acquisition and output with high speed are realized. Meanwhile, due to the traditional speech enhancement method which has the problems as bad adaptability, slow convergence speed and big steady-state error, versiera function and de-correlation principle were used to improve the existing adaptive filtering algorithm, which effectively enhanced the quality of voice communications. Test results verified the stability of the system and the de-noising performance of the algorithm, and it also proved that they could provide clearer speech signals for the deaf or tinnitus patients.

An ecological vegetation-activated sludge process (V-ASP) for decentralized wastewater treatment: system development, treatment performance, and mathematical modeling.

PubMed

Yuan, Jiajia; Dong, Wenyi; Sun, Feiyun; Li, Pu; Zhao, Ke

2016-05-01

An environment-friendly decentralized wastewater treatment process that is comprised of activated sludge process (ASP) and wetland vegetation, named as vegetation-activated sludge process (V-ASP), was developed for decentralized wastewater treatment. The long-term experimental results evidenced that the vegetation sequencing batch reactor (V-SBR) process had consistently stable higher removal efficiencies of organic substances and nutrients from domestic wastewater compared with traditional sequencing batch reactor (SBR). The vegetation allocated into V-SBR system could not only remove nutrients through its vegetation transpiration ratio but also provide great surface area for microorganism activity enhancement. This high vegetation transpiration ratio enhanced nutrients removal effectiveness from wastewater mainly by flux enhancement, oxygen and substrate transportation acceleration, and vegetation respiration stimulation. A mathematical model based on ASM2d was successfully established by involving the specific function of vegetation to simulate system performance. The simulation results on the influence of operational parameters on V-ASP treatment effectiveness demonstrated that V-SBR had a high resistance to seasonal temperature fluctuations and influent loading shocking.

Foveal Processing Under Concurrent Peripheral Load in Profoundly Deaf Adults.

PubMed

Dye, Matthew W G

2016-04-01

Development of the visual system typically proceeds in concert with the development of audition. One result is that the visual system of profoundly deaf individuals differs from that of those with typical auditory systems. While past research has suggested deaf people have enhanced attention in the visual periphery, it is still unclear whether or not this enhancement entails deficits in central vision. Profoundly deaf and typically hearing adults were administered a variant of the useful field of view task that independently assessed performance on concurrent central and peripheral tasks. Identification of a foveated target was impaired by a concurrent selective peripheral attention task, more so in profoundly deaf adults than in the typically hearing. Previous findings of enhanced performance on the peripheral task were not replicated. These data are discussed in terms of flexible allocation of spatial attention targeted towards perceived task demands, and support a modified "division of labor" hypothesis whereby attentional resources co-opted to process peripheral space result in reduced resources in the central visual field. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Performance assessment of small-package-class nonintrusive inspection systems

NASA Astrophysics Data System (ADS)

Spradling, Michael L.; Hyatt, Roger

1997-02-01

The DoD Counterdrug Technology Development Program has addressed the development and demonstration of technology to enhance nonintrusive inspection of small packages such as passenger baggage, commercially delivered parcels, and breakbulk cargo items. Within the past year they have supported several small package-class nonintrusive inspection system performance assessment activities. All performance assessment programs involved the use of a red/blue team concept and were conducted in accordance with approved assessment protocols. This paper presents a discussion related to the systematic performance assessment of small package-class nonintrusive inspection technologies, including transmission, backscatter and computed tomography x-ray imaging, and protocol-related considerations for the assessment of these systems.

Quality Management and Key Performance Indicators in Oncologic Esophageal Surgery.

PubMed

Gockel, Ines; Ahlbrand, Constantin Johannes; Arras, Michael; Schreiber, Elke Maria; Lang, Hauke

2015-12-01

Ranking systems and comparisons of quality and performance indicators will be of increasing relevance for complex "high-risk" procedures such as esophageal cancer surgery. The identification of evidence-based standards relevant for key performance indicators in esophageal surgery is essential for establishing monitoring systems and furthermore a requirement to enhance treatment quality. In the course of this review, we analyze the key performance indicators case volume, radicality of resection, and postoperative morbidity and mortality, leading to continuous quality improvement. Ranking systems established on this basis will gain increased relevance in highly complex procedures within the national and international comparison and furthermore improve the treatment of patients with esophageal carcinoma.

Metrics for the technical performance evaluation of light water reactor accident-tolerant fuel

DOE PAGES

Bragg-Sitton, Shannon M.; Todosow, Michael; Montgomery, Robert; ...

2017-03-26

The safe, reliable, and economic operation of the nation’s nuclear power reactor fleet has always been a top priority for the nuclear industry. Continual improvement of technology, including advanced materials and nuclear fuels, remains central to the industry’s success. Enhancing the accident tolerance of light water reactors (LWRs) became a topic of serious discussion following the 2011 Great East Japan Earthquake, resulting tsunami, and subsequent damage to the Fukushima Daiichi nuclear power plant complex. The overall goal for the development of accident-tolerant fuel (ATF) for LWRs is to identify alternative fuel system technologies to further enhance the safety, competitiveness, andmore » economics of commercial nuclear power. Designed for use in the current fleet of commercial LWRs or in reactor concepts with design certifications (GEN-III+), fuels with enhanced accident tolerance would endure loss of active cooling in the reactor core for a considerably longer period of time than the current fuel system while maintaining or improving performance during normal operations. The complex multiphysics behavior of LWR nuclear fuel in the integrated reactor system makes defining specific material or design improvements difficult; as such, establishing desirable performance attributes is critical in guiding the design and development of fuels and cladding with enhanced accident tolerance. Research and development of ATF in the United States is conducted under the U.S. Department of Energy (DOE) Fuel Cycle Research and Development Advanced Fuels Campaign. The DOE is sponsoring multiple teams to develop ATF concepts within multiple national laboratories, universities, and the nuclear industry. Concepts under investigation offer both evolutionary and revolutionary changes to the current nuclear fuel system. This study summarizes the technical evaluation methodology proposed in the United States to aid in the optimization and prioritization of candidate ATF designs.« less

Updated Heliostorm Warning Mission: Enhancements Based on New Technology

NASA Technical Reports Server (NTRS)

Young, Roy M.

2007-01-01

The Heliostorm (also referred to as Geostorm) mission has been regarded as the best choice for the first application of solar sail technology. The objective of Heliostorm is to obtain data from an orbit station slightly displaced from the ecliptic at or nearer to the Sun than 0.98 AU, which places it twice as close to the sun as Earth's natural L1 point at 0.993 AU. The maintenance of such an orbit location would require prohibitive amounts of propellants using chemical or electric propulsion systems; however, a solar sailcraft is ideally suited for this purpose because it relies solely on the propulsive force from photons for orbit maintenance. Heliostorm has been the subject of several mission studies over the past decade, with the most complete study conducted in 1999 in conjunction with a proposed New Millennium Program (NMP) Space Technology 5 (ST-5) flight opportunity. Recently, over a two and one-half year period dating from 2003 through 2005, NASA's In-Space Propulsion Technology Program (ISTP) matured solar sail technology from laboratory components to full systems, demonstrated in as relevant a space environment as could feasibly be simulated on the ground. Work under this program has yielded promising results for enhanced Heliostorm mission performance. This enhanced performance is achievable principally through reductions in the sail areal density. These reductions are realized through the use of lower linear mass density booms, a thinner sail membrane, and increased sail area. Advancements in sailcraft vehicle system design also offer potential mass reductions and hence improved performance. This paper will present the preliminary results of an updated Heliostorm mission design study including the enhancements incorporated during the design, development, analysis and testing of the system ground demonstrator.

A novel implantable catheter system with transcutaneous port for intermittent convection-enhanced delivery of carboplatin for recurrent glioblastoma.

PubMed

Barua, Neil U; Hopkins, Kirsten; Woolley, Max; O'Sullivan, Stephen; Harrison, Rob; Edwards, Richard J; Bienemann, Alison S; Wyatt, Marcella J; Arshad, Azeem; Gill, Steven S

2016-01-01

Inadequate penetration of the blood-brain barrier (BBB) by systemically administered chemotherapies including carboplatin is implicated in their failure to improve prognosis for patients with glioblastoma. Convection-enhanced delivery (CED) of carboplatin has the potential to improve outcomes by facilitating bypass of the BBB. We report the first use of an implantable CED system incorporating a novel transcutaneous bone-anchored port (TBAP) for intermittent CED of carboplatin in a patient with recurrent glioblastoma. The CED catheter system was implanted using a robot-assisted surgical method. Catheter targeting accuracy was verified by performing intra-operative O-arm imaging. The TBAP was implanted using a skin-flap dermatome technique modeled on bone-anchored hearing aid surgery. Repeated infusions were performed by attaching a needle administration set to the TBAP. Drug distribution was monitored with serial real-time T2-weighted magnetic resonance imaging (MRI). All catheters were implanted to within 1.5 mm of their planned target. Intermittent infusions of carboplatin were performed on three consecutive days and repeated after one month without the need for further surgical intervention. Infused volumes of 27.9 ml per day were well tolerated, with the exception of a single seizure episode. Follow-up MRI at eight weeks demonstrated a significant reduction in the volume of tumor enhancement from 42.6 ml to 24.6 ml, and was associated with stability of the patient's clinical condition. Reduction in the volume of tumor enhancement indicates that intermittent CED of carboplatin has the potential to improve outcomes in glioblastoma. The novel technology described in this report make intermittent CED infusion regimes an achievable treatment strategy.

Updated Heliostorm Warning Mission: Enhancements Based on New Technology

NASA Technical Reports Server (NTRS)

Young, Roy M.

2007-01-01

The Heliostorm (also referred to as Geostorm) mission has been regarded as the best choice for the first application of solar sail technology. The objective of Heliostorm is to obtain data from an orbit station slightly displaced from the ecliptic at or nearer to the Sun than 0.98 AU, which places it twice as dose to the sun as Earth's natural L1 point at 0.993 AU. The maintenance of such an orbit location would require prohibitive amounts of propellants using chemical or electric propulsion systems; however, a solar sailcraft is ideally suited for this purpose because it relies solely on the propulsive force from photons for orbit maintenance. Heliostorm has been the subject of several mission studies over the past decade, with the most complete study conducted in 1999 in conjunction with a proposed New Millennium Program (NMP) Space Technology 5 (ST-5) flight opportunity. Recently, over a two and one-half year period dating from 2003 through 2005, NASA's In-Space Propulsion Technology Program (ISTP) matured solar sail technology from laboratory components to full systems, demonstrated in as relevant a space environment as could feasibly be simulated on the ground. Work under this program has yielded promising results for enhanced Heliostorm mission performance. This enhanced performance is achievable principally through reductions in the sail areal density. These reductions are realized through the use of lower linear mass density booms, a thinner sail membrane, and increased sail area. Advancements in sailcraft vehicle system design also offer potential mass reductions and hence improved performance. This paper will present the preliminary results of an updated Heliostorm mission design study including the enhancements incorporated during the design, development, analysis and testing of the system ground demonstrator.

An Analysis of Performance-Based Funding Policies and Recommendations for the Florida College System

ERIC Educational Resources Information Center

Balog, Scott E.

2016-01-01

Nearly 30 states have adopted or are transitioning to performance-based funding programs for community colleges that allocate funding based on institutional performance according to defined metrics. While embraced by state lawmakers and promoted by outside advocacy groups as a method to improve student outcomes, enhance accountability and ensure…

Various on-chip sensors with microfluidics for biological applications.

PubMed

Lee, Hun; Xu, Linfeng; Koh, Domin; Nyayapathi, Nikhila; Oh, Kwang W

2014-09-12

In this paper, we review recent advances in on-chip sensors integrated with microfluidics for biological applications. Since the 1990s, much research has concentrated on developing a sensing system using optical phenomena such as surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS) to improve the sensitivity of the device. The sensing performance can be significantly enhanced with the use of microfluidic chips to provide effective liquid manipulation and greater flexibility. We describe an optical image sensor with a simpler platform for better performance over a larger field of view (FOV) and greater depth of field (DOF). As a new trend, we review consumer electronics such as smart phones, tablets, Google glasses, etc. which are being incorporated in point-of-care (POC) testing systems. In addition, we discuss in detail the current optical sensing system integrated with a microfluidic chip.

Landsat-7 Enhanced Thematic Mapper plus radiometric calibration

USGS Publications Warehouse

Markham, B.L.; Boncyk, Wayne C.; Helder, D.L.; Barker, J.L.

1997-01-01

Landsat-7 is currently being built and tested for launch in 1998. The Enhanced Thematic Mapper Plus (ETM+) sensor for Landsat-7, a derivative of the highly successful Thematic Mapper (TM) sensors on Landsats 4 and 5, and the Landsat-7 ground system are being built to provide enhanced radiometric calibration performance. In addition, regular vicarious calibration campaigns are being planned to provide additional information for calibration of the ETM+ instrument. The primary upgrades to the instrument include the addition of two solar calibrators: the full aperture solar calibrator, a deployable diffuser, and the partial aperture solar calibrator, a passive device that allows the ETM+ to image the sun. The ground processing incorporates for the first time an off-line facility, the Image Assessment System (IAS), to perform calibration, evaluation and analysis. Within the IAS, processing capabilities include radiometric artifact characterization and correction, radiometric calibration from the multiple calibrator sources, inclusion of results from vicarious calibration and statistical trending of calibration data to improve calibration estimation. The Landsat Product Generation System, the portion of the ground system responsible for producing calibrated products, will incorporate the radiometric artifact correction algorithms and will use the calibration information generated by the IAS. This calibration information will also be supplied to ground processing systems throughout the world.

MetAlign 3.0: performance enhancement by efficient use of advances in computer hardware.

PubMed

Lommen, Arjen; Kools, Harrie J

2012-08-01

A new, multi-threaded version of the GC-MS and LC-MS data processing software, metAlign, has been developed which is able to utilize multiple cores on one PC. This new version was tested using three different multi-core PCs with different operating systems. The performance of noise reduction, baseline correction and peak-picking was 8-19 fold faster compared to the previous version on a single core machine from 2008. The alignment was 5-10 fold faster. Factors influencing the performance enhancement are discussed. Our observations show that performance scales with the increase in processor core numbers we currently see in consumer PC hardware development.

Enhanced Internet firewall design using stateful filters final report

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

Hutchins, J.A.; Simons, R.W.

1997-08-01

The current state-of-the-art in firewall design provides a lot of security for company networks, but normally at the expense of performance and/or functionality. Sandia researched a new approach to firewall design which incorporates a highly stateful approach, allowing much more flexibility for protocol checking and manipulation while retaining performance. A prototype system was built and multiple protocol policy modules implemented to test the concept. The resulting system, though implemented on a low-power workstation, performed almost at the same performance as Sandia`s current firewall.

Recent Enhancements to the National Transonic Facility

NASA Technical Reports Server (NTRS)

Kilgore, W. A.; Balakrishna, S.; Bobbitt, C. W.; Underwood, P.

2003-01-01

The National Transonic Facility continues to make enhancements to provide quality data in a safe, efficient and cost effective method for aerodynamic ground testing. Recent enhancements discussed in this paper include the restoration of reliability and improved performance of the heat exchanger systems resulting in the expansion of the NTF air operations envelope. Additionally, results are presented from a continued effort to reduce model dynamics through the use of a new stiffer balance and sting

Investigation of kinetics of MOCVD systems

NASA Astrophysics Data System (ADS)

Anderson, Timothy J.

1991-12-01

Several issues related to epitaxy of III-V semiconductors by hydride VPE and MOCVD were investigated. A complex chemical equilibrium analysis was performed in order to investigate the controllability of hydride VPE. The critical control parameters for the deposition of InGaAsP Lattice matched to InP are deposition temperature, system pressure, Group III Molar Ratio, Group V Molar Ratio. An experimental characterization of the Ga and In source reactors was accomplished. A MOCVD System was constructed for the deposition of AlGaAs. An investigation was performed to determine the controlling parameters of laser-enhanced deposition of GaAs and AlGaAs using an argon ion laser. Enhancement of deposition was observed when the system was operated in the reaction limited regime. The use of a Ga/In alloy source was studied for the deposition of GaInAs by the Hydride method. The system was used to produce state-of-the-art P-I-N photo-detectors.

FUZZY LOGIC BASED INTELLIGENT CONTROL OF A VARIABLE SPEED CAGE MACHINE WIND GENERATION SYSTEM

EPA Science Inventory

The paper describes a variable-speed wind generation system where fuzzy logic principles are used to optimize efficiency and enhance performance control. A squirrel cage induction generator feeds the power to a double-sided pulse width modulated converter system which either pump...

Learning Management System with Prediction Model and Course-Content Recommendation Module

ERIC Educational Resources Information Center

Evale, Digna S.

2017-01-01

Aim/Purpose: This study is an attempt to enhance the existing learning management systems today through the integration of technology, particularly with educational data mining and recommendation systems. Background: It utilized five-year historical data to find patterns for predicting student performance in Java Programming to generate…

The enhanced longevity and liver targetability of Paclitaxel by hybrid liposomes encapsulating Paclitaxel-conjugated gold nanoparticles.

PubMed

Bao, Quan-Ying; Zhang, Ning; Geng, Dong-Dong; Xue, Jing-Wei; Merritt, Mackenzie; Zhang, Can; Ding, Ya

2014-12-30

Organic and inorganic drug delivery systems both demonstrate their own advantages and challenges in practical applications. Combining these two drug delivery strategies in one system is expected to solve their current issues and achieve desirable functions. In this paper, gold nanoparticles (GNPs) and liposomes have been chosen as the model systems to construct a hybrid system and investigate its performance for the tumor therapy of Paclitaxel (PTX). The thiol-terminated polyethylene glycol (PEG400)-PTX derivative has been covalently modified on the surface of GNPs, followed by the encapsulation of PTX-conjugated GNPs (PTX-PEG400@GNPs) in liposomes. The hybrid liposomes solve the solubility and stability problems of gold conjugates and show high drug loading capacity. In vitro PTX release from the hybrid system maintains the similar sustained behavior demonstrated in its conjugates. Under the protection of a biocompatible liposome shell, encapsulated PTX shows enhanced circulation longevity and liver targetability compared to Taxol(®) and PTX-PEG400@GNPs suspension in the pharmacokinetic and biodistribution studies. These indicate that encapsulating drug-conjugated inorganic nanoparticles inside organic carriers maintains the superiority of both vehicles and improves the performance of hybrid systems. Although these attributes of hybrid liposomes lead to a better therapeutic capacity in a murine liver cancer model than that of the comparison groups, it shows no significant difference from Taxol(®) and conjugate suspension. This result could be due to the delayed and sustained drug release from the system. However, it indicates the promising potential for these hybrid liposomes will allow further construction of a compound preparation with improved performance that is based on their enhanced longevity and liver targetability of Paclitaxel. Copyright © 2014 Elsevier B.V. All rights reserved.

Performance and reliability enhancement of linear coolers

NASA Astrophysics Data System (ADS)

Mai, M.; Rühlich, I.; Schreiter, A.; Zehner, S.

2010-04-01

Highest efficiency states a crucial requirement for modern tactical IR cryocooling systems. For enhancement of overall efficiency, AIM cryocooler designs where reassessed considering all relevant loss mechanisms and associated components. Performed investigation was based on state-of-the-art simulation software featuring magnet circuitry analysis as well as computational fluid dynamics (CFD) to realistically replicate thermodynamic interactions. As a result, an improved design for AIM linear coolers could be derived. This paper gives an overview on performance enhancement activities and major results. An additional key-requirement for cryocoolers is reliability. In recent time, AIM has introduced linear coolers with full Flexure Bearing suspension on both ends of the driving mechanism incorporating Moving Magnet piston drive. In conjunction with a Pulse-Tube coldfinger these coolers are capable of meeting MTTF's (Mean Time To Failure) in excess of 50,000 hours offering superior reliability for space applications. Ongoing development also focuses on reliability enhancement, deriving space technology into tactical solutions combining both, excelling specific performance with space like reliability. Concerned publication will summarize the progress of this reliability program and give further prospect.

Contribution of variable-speed pump hydro storage for power system dynamic performance

NASA Astrophysics Data System (ADS)

Silva, B.; Moreira, C.

2017-04-01

This paper presents the study of variable-speed Pump Storage Powerplant (PSP) in the Portuguese power system. It evaluates the progressive integration in three major locations and compares the power system performance following a severe fault event with consequent disconnection of non-Fault Ride-through (FRT) compliant Wind Farms (WF). To achieve such objective, a frequency responsive model was developed in PSS/E and was further used to substitute existing fixed-speed PSP. The results allow identifying a clear enhancement on the power system performance by the presence of frequency responsive variable-speed PSP, especially for the scenario presented, with high level of renewables integration.

Performance evaluation of stereo endoscopic imaging system incorporating TFT-LCD.

PubMed

Song, C-G; Park, S-K

2005-01-01

This paper presents a 3D endoscopic video system designed to improve visualization and enhance the ability of the surgeon to perform delicate endoscopic surgery. In a comparison of the polarized and electric shutter-type stereo imaging systems, the former was found to be superior in terms of both accuracy and speed for knot-tying and for the loop pass test. The results of our experiments show that the proposed 3D endoscopic system has a sufficiently wide viewing angle and zone for multi-viewing, and that it provides better image quality and more stable optical performance compared with the electric shutter-type.

NASA Runway Incursion Prevention System (RIPS) Dallas-Fort Worth Demonstration Performance Analysis

NASA Technical Reports Server (NTRS)

Cassell, Rick; Evers, Carl; Esche, Jeff; Sleep, Benjamin; Jones, Denise R. (Technical Monitor)

2002-01-01

NASA's Aviation Safety Program Synthetic Vision System project conducted a Runway Incursion Prevention System (RIPS) flight test at the Dallas-Fort Worth International Airport in October 2000. The RIPS research system includes advanced displays, airport surveillance system, data links, positioning system, and alerting algorithms to provide pilots with enhanced situational awareness, supplemental guidance cues, a real-time display of traffic information, and warnings of runway incursions. This report describes the aircraft and ground based runway incursion alerting systems and traffic positioning systems (Automatic Dependent Surveillance - Broadcast (ADS-B) and Traffic Information Service - Broadcast (TIS-B)). A performance analysis of these systems is also presented.

Molecular dynamics coupled with a virtual system for effective conformational sampling.

PubMed

Hayami, Tomonori; Kasahara, Kota; Nakamura, Haruki; Higo, Junichi

2018-07-15

An enhanced conformational sampling method is proposed: virtual-system coupled canonical molecular dynamics (VcMD). Although VcMD enhances sampling along a reaction coordinate, this method is free from estimation of a canonical distribution function along the reaction coordinate. This method introduces a virtual system that does not necessarily obey a physical law. To enhance sampling the virtual system couples with a molecular system to be studied. Resultant snapshots produce a canonical ensemble. This method was applied to a system consisting of two short peptides in an explicit solvent. Conventional molecular dynamics simulation, which is ten times longer than VcMD, was performed along with adaptive umbrella sampling. Free-energy landscapes computed from the three simulations mutually converged well. The VcMD provided quicker association/dissociation motions of peptides than the conventional molecular dynamics did. The VcMD method is applicable to various complicated systems because of its methodological simplicity. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Exploration of GPS to enhance the safe transport of hazardous materials

DOT National Transportation Integrated Search

1997-12-01

The report (1) documents a set of requirements for the performance of location systems that utilize the Global Positioning System (GPS), (2) identifies potential uses of GPS in hazardous materials transport, (3) develops service descriptions for the ...

Institutional and Economic Determinants of Public Health System Performance

PubMed Central

Mays, Glen P.; McHugh, Megan C.; Shim, Kyumin; Perry, Natalie; Lenaway, Dennis; Halverson, Paul K.; Moonesinghe, Ramal

2006-01-01

Objectives. Although a growing body of evidence demonstrates that availability and quality of essential public health services vary widely across communities, relatively little is known about the factors that give rise to these variations. We examined the association of institutional, financial, and community characteristics of local public health delivery systems and the performance of essential services. Methods. Performance measures were collected from local public health systems in 7 states and combined with secondary data sources. Multivariate, linear, and nonlinear regression models were used to estimate associations between system characteristics and the performance of essential services. Results. Performance varied significantly with the size, financial resources, and organizational structure of local public health systems, with some public health services appearing more sensitive to these characteristics than others. Staffing levels and community characteristics also appeared to be related to the performance of selected services. Conclusions. Reconfiguring the organization and financing of public health systems in some communities—such as through consolidation and enhanced intergovernmental coordination—may hold promise for improving the performance of essential services. PMID:16449584

The use of energy drinks, dietary supplements, and prescription medications by United States college students to enhance athletic performance.

PubMed

Hoyte, Christopher O; Albert, Donald; Heard, Kennon J

2013-06-01

While the use of performance enhancing substances by professional, collegiate, and Olympic athletes is well described, the rate of use in the general population is not well studied. We explored the use of energy drinks, dietary supplements, and prescription medications for the enhancement of athletic performance among college students using an ongoing survey system. We conducted a multi-round online questionnaire collecting data from self-identified students at two-year colleges, four-year colleges, online courses, or technical schools at least part-time during the specified sampling period. The sample is obtained through the use of a survey panel company in which respondents voluntarily register. Survey data were collected from December, 2010 through August, 2011. Subjects who reported participating in athletics were asked if they used any of the following substances to enhance athletic performance (1) energy drinks (2) dietary supplements (3) prescription medications within the last year. Data were analyzed from October, 2011 through January, 2012. There were 462 college students who responded to the survey reporting they participate in sports at various levels. Of these, 397 (85.9 %) responded that within the last year they used energy drinks, dietary supplements, or prescription medications to enhance athletic performance. Energy drinks had the highest prevalence (80.1 %), followed by dietary supplements (64.1 %) and prescription medications (53.3 %). Use was most prevalent amongst intercollegiate athletes (89.4 %) followed by club (88.5 %) and intermural (82.1 %) participants. The vast majority of survey respondents reported using energy drinks, dietary supplements, and prescription medications within the last year for athletic performance enhancement.

Cleaning Insertions and Collimation Challenges

NASA Astrophysics Data System (ADS)

Redaelli, S.; Appleby, R. B.; Bertarelli, A.; Bruce, R.; Jowett, J. M.; Lechner, A.; Losito, R.

High-performance collimation systems are essential for operating efficiently modern hadron machine with large beam intensities. In particular, at the LHC the collimation system ensures a clean disposal of beam halos in the superconducting environment. The challenges of the HL-LHC study pose various demanding requests for beam collimation. In this paper we review the present collimation system and its performance during the LHC Run 1 in 2010-2013. Various collimation solutions under study to address the HL-LHC requirements are then reviewed, identifying the main upgrade baseline and pointing out advanced collimation concept for further enhancement of the performance.

Z-scheme Ag3PO4/POM/GO heterojunction with enhanced photocatalytic performance for degradation and water splitting.

PubMed

Liu, Guodong; Zhao, Xinfu; Zhang, Jian; Liu, Shaojie; Sha, Jingquan

2018-05-01

To develop solar light-driven photocatalysts with high activity and structural stability, Ag3PO4/POM/GO heterojunction has been successfully prepared by a facile method at room temperature. Ag3PO4/POM/GO shows remarkably enhanced activity and stability for photocatalytic degradation and H2 production from water-splitting under simulated solar light. The degradation rate of Ag3PO4/POM/GO is 1.8 times and 1.2 times those of Ag3PO4 and Ag3PO4/POMs, respectively. H2 production using Ag3PO4/POM/GO is 2.0 times that of Ag3PO4/GO. The enhanced photocatalytic performance of Ag3PO4/POM/GO is attributed to the increased surface area, electronegativity and structure stability. The Z-scheme system of Ag3PO4/POM/GO effectively promotes charge separation, resulting in enhanced photocatalytic performance under simulated solar light.

Preliminary MIPCC Enhanced F-4 and F-15 Preformance Characteristics for a First Stage Reusable Launch Vehicle

NASA Technical Reports Server (NTRS)

Kloesel, Kurt J.; Clark, Casie M.

2013-01-01

Performance increases in turbojet engines can theoretically be achieved through Mass Injection Pre-Compressor Cooling (MIPCC), a process involving injecting water or oxidizer or both into an afterburning turbojet engine. The injection of water results in pre-compressor cooling, allowing the propulsion system to operate at high altitudes and Mach numbers. In this way, a MIPCC-enhanced turbojet engine could be used to power the first stage of a reusable launch vehicle or be integrated into an existing aircraft that could launch a 100-lbm payload to a reference 100-nm altitude orbit at 28 deg inclination. The two possible candidates for MIPCC flight demonstration that are evaluated in this study are the F-4 Phantom II airplane and the F-15 Eagle airplane (both of McDonnell Douglas, now The Boeing Company, Chicago, Illinois), powered by two General Electric Company (Fairfield, Connecticut) J79 engines and two Pratt & Whitney (East Hartford, Connecticut) F100-PW-100 engines, respectively. This paper presents a conceptual discussion of the theoretical performance of each of these aircraft using MIPCC propulsion techniques. Trajectory studies were completed with the Optimal Trajectories by Implicit Simulation (OTIS) software (NASA Glenn Research Center, Cleveland, Ohio) for a standard F-4 airplane and a standard F-15 airplane. Standard aircraft simulation models were constructed, and the thrust in each was altered in accordance with estimated MIPCC performance characteristics. The MIPCC and production aircraft model results were then reviewed to assess the feasibility of a MIPCC-enhanced propulsion system for use as a first-stage reusable launch vehicle; it was determined that the MIPCC-enhanced F-15 model showed a significant performance advantage over the MIPCC-enhanced F-4 model.

Automated inspection of hot steel slabs

DOEpatents

Martin, R.J.

1985-12-24

The disclosure relates to a real time digital image enhancement system for performing the image enhancement segmentation processing required for a real time automated system for detecting and classifying surface imperfections in hot steel slabs. The system provides for simultaneous execution of edge detection processing and intensity threshold processing in parallel on the same image data produced by a sensor device such as a scanning camera. The results of each process are utilized to validate the results of the other process and a resulting image is generated that contains only corresponding segmentation that is produced by both processes. 5 figs.

Automated inspection of hot steel slabs

DOEpatents

Martin, Ronald J.

1985-01-01

The disclosure relates to a real time digital image enhancement system for performing the image enhancement segmentation processing required for a real time automated system for detecting and classifying surface imperfections in hot steel slabs. The system provides for simultaneous execution of edge detection processing and intensity threshold processing in parallel on the same image data produced by a sensor device such as a scanning camera. The results of each process are utilized to validate the results of the other process and a resulting image is generated that contains only corresponding segmentation that is produced by both processes.

Systems level test and simulation for photonic processing systems

NASA Astrophysics Data System (ADS)

Erteza, I. A.; Stalker, K. T.

1995-08-01

Photonic technology is growing in importance throughout DOD. Programs have been underway in each of the Services to demonstrate the ability of photonics to enhance current electronic performance in several prototype systems, such as the Navy's SLQ-32 radar warning receiver, the Army's multi-role survivable radar and the phased array radar controller for the Airborne Warning and Control System (AWACS) upgrade. Little, though, is known about radiation effects; the component studies do not furnish the information needed to predict overall system performance in a radiation environment. To date, no comprehensive test and analysis program has been conducted to evaluate sensitivity of overall system performance to the radiation environment. The goal of this program is to relate component level effects to system level performance through modeling and testing of a selected optical processing system, and to help direct component testing to items which can directly and adversely affect overall system performance. This report gives a broad overview of the project, highlighting key results.

Active Tailoring of Lift Distribution to Enhance Cruise Performance

NASA Technical Reports Server (NTRS)

Flamm, Jeffrey D. (Technical Monitor); Pfeiffer, Neal J.; Christians, Joel G.

2005-01-01

During Phase I of this project, Raytheon Aircraft Company (RAC) has analytically and experimentally evaluated key components of a system that could be implemented for active tailoring of wing lift distribution using low-drag, trailing-edge modifications. Simple systems such as those studied by RAC could be used to enhance the cruise performance of a business jet configuration over a range of typical flight conditions. The trailing-edge modifications focus on simple, deployable mechanisms comprised of extendable small flap panels over portions of the span that could be used to subtly but positively optimize the lift and drag characteristics. The report includes results from low speed wind tunnel testing of the trailing-edge devices, descriptions of potential mechanisms for automation, and an assessment of the technology.

PERVAPORATION SEPARATION IMPROVEMENTS VIA FRACTIONAL CONDENSATION (DEPHLEGMATION): IMPACT OF DEPHLEGMATOR DESIGN ON PERFORMANCE

EPA Science Inventory

Traditionally, pervaporation systems have been operated using a total condenser to deliver the final permeate liquid product. Over the past two years, we have investigated the use of a condensation process called "dephlegmation" to enhance the separation performance of pervapora...

New approach to enhance and evaluate the performance of vehicle-infrastructure integration and its communication systems, final report.

DOT National Transportation Integrated Search

2010-09-01

Initial research studied the use of wireless local area networks (WLAN) protocols in Inter-Vehicle Communications : (IVC) environments. The protocols performance was evaluated in terms of measuring throughput, jitter time and : delay time. This re...

Web-based integrated public healthcare information system of Korea: development and performance.

PubMed

Ryu, Seewon; Park, Minsu; Lee, Jaegook; Kim, Sung-Soo; Han, Bum Soo; Mo, Kyoung Chun; Lee, Hyung Seok

2013-12-01

The Web-based integrated public healthcare information system (PHIS) of Korea was planned and developed from 2005 to 2010, and it is being used in 3,501 regional health organizations. This paper introduces and discusses development and performance of the system. We reviewed and examined documents about the development process and performance of the newly integrated PHIS. The resources we analyzed the national plan for public healthcare, information strategy for PHIS, usage and performance reports of the system. The integrated PHIS included 19 functional business areas, 47 detailed health programs, and 48 inter-organizational tasks. The new PHIS improved the efficiency and effectiveness of the business process and inter-organizational business, and enhanced user satisfaction. Economic benefits were obtained from five categories: labor, health education and monitoring, clinical information management, administration and civil service, and system maintenance. The system was certified by a patent from the Korean Intellectual Property Office and accredited as an ISO 9001. It was also reviewed and received preliminary comments about its originality, advancement, and business applicability from the Patent Cooperation Treaty. It has been found to enhance the quality of policy decision-making about regional healthcare at the self-governing local government level. PHIS, a Web-based integrated system, has contributed to the improvement of regional healthcare services of Korea. However, when it comes to an appropriate evolution, the needs and changing environments of community-level healthcare service and IT infrastructure should be analyzed properly in advance.

Web-Based Integrated Public Healthcare Information System of Korea: Development and Performance

PubMed Central

Park, Minsu; Lee, Jaegook; Kim, Sung-Soo; Han, Bum Soo; Mo, Kyoung Chun; Lee, Hyung Seok

2013-01-01

Objectives The Web-based integrated public healthcare information system (PHIS) of Korea was planned and developed from 2005 to 2010, and it is being used in 3,501 regional health organizations. This paper introduces and discusses development and performance of the system. Methods We reviewed and examined documents about the development process and performance of the newly integrated PHIS. The resources we analyzed the national plan for public healthcare, information strategy for PHIS, usage and performance reports of the system. Results The integrated PHIS included 19 functional business areas, 47 detailed health programs, and 48 inter-organizational tasks. The new PHIS improved the efficiency and effectiveness of the business process and inter-organizational business, and enhanced user satisfaction. Economic benefits were obtained from five categories: labor, health education and monitoring, clinical information management, administration and civil service, and system maintenance. The system was certified by a patent from the Korean Intellectual Property Office and accredited as an ISO 9001. It was also reviewed and received preliminary comments about its originality, advancement, and business applicability from the Patent Cooperation Treaty. It has been found to enhance the quality of policy decision-making about regional healthcare at the self-governing local government level. Conclusions PHIS, a Web-based integrated system, has contributed to the improvement of regional healthcare services of Korea. However, when it comes to an appropriate evolution, the needs and changing environments of community-level healthcare service and IT infrastructure should be analyzed properly in advance. PMID:24523997

Extended-Kalman-filter-based regenerative and friction blended braking control for electric vehicle equipped with axle motor considering damping and elastic properties of electric powertrain

NASA Astrophysics Data System (ADS)

Lv, Chen; Zhang, Junzhi; Li, Yutong

2014-11-01

Because of the damping and elastic properties of an electrified powertrain, the regenerative brake of an electric vehicle (EV) is very different from a conventional friction brake with respect to the system dynamics. The flexibility of an electric drivetrain would have a negative effect on the blended brake control performance. In this study, models of the powertrain system of an electric car equipped with an axle motor are developed. Based on these models, the transfer characteristics of the motor torque in the driveline and its effect on blended braking control performance are analysed. To further enhance a vehicle's brake performance and energy efficiency, blended braking control algorithms with compensation for the powertrain flexibility are proposed using an extended Kalman filter. These algorithms are simulated under normal deceleration braking. The results show that the brake performance and blended braking control accuracy of the vehicle are significantly enhanced by the newly proposed algorithms.

Performance evaluation of the insurance companies based on AHP

NASA Astrophysics Data System (ADS)

Lu, Manhong; Zhu, Kunping

2018-04-01

With the entry of foreign capital, China's insurance industry is under increasing pressure of competition. The performance of a company is the external manifestation of its comprehensive strength. Therefore, the establishment of a scientific evaluation system is of practical significance for the insurance companies. In this paper, based on the financial and non-financial indicators of the companies, the performance evaluation system is constructed by means of the analytic hierarchy process (AHP). In the system, the weights of the indicators which represent the impact on the performance of the companies will be calculated by the process. The evaluation system is beneficial for the companies to realize their own strengths and weaknesses, so as to take steps to enhance the core competitiveness of the companies.

Effective Team Support: From Modeling to Software Agents

NASA Technical Reports Server (NTRS)

Remington, Roger W. (Technical Monitor); John, Bonnie; Sycara, Katia

2003-01-01

The purpose of this research contract was to perform multidisciplinary research between CMU psychologists, computer scientists and engineers and NASA researchers to design a next generation collaborative system to support a team of human experts and intelligent agents. To achieve robust performance enhancement of such a system, we had proposed to perform task and cognitive modeling to thoroughly understand the impact technology makes on the organization and on key individual personnel. Guided by cognitively-inspired requirements, we would then develop software agents that support the human team in decision making, information filtering, information distribution and integration to enhance team situational awareness. During the period covered by this final report, we made substantial progress in modeling infrastructure and task infrastructure. Work is continuing under a different contract to complete empirical data collection, cognitive modeling, and the building of software agents to support the teams task.

Optimizing raid performance with cache

NASA Technical Reports Server (NTRS)

Bouzari, Alex

1994-01-01

We live in a world of increasingly complex applications and operating systems. Information is increasing at a mind-boggling rate. The consolidation of text, voice, and imaging represents an even greater challenge for our information systems. Which forced us to address three important questions: Where do we store all this information? How do we access it? And, how do we protect it against the threat of loss or damage? Introduced in the 1980s, RAID (Redundant Arrays of Independent Disks) represents a cost-effective solution to the needs of the information age. While fulfilling expectations for high storage, and reliability, RAID is sometimes subject to criticisms in the area of performance. However, there are design elements that can significantly enhance performance. They can be subdivided into two areas: (1) RAID levels or basic architecture. And, (2) enhancement schemes such as intelligent caching, support of tagged command queuing, and use of SCSI-2 Fast and Wide features.

Heart rate variability interventions for concussion and rehabilitation

PubMed Central

Conder, Robert L.; Conder, Alanna A.

2014-01-01

The study of heart rate variability (HRV) has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain). It is well-established that lack of HRV implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal HRV has been associated with good cardiovascular health, autonomic nervous system (ANS) control, emotional regulation, and enhanced neurocognitive processing. In addition to health benefits, optimal HRV has been shown to improve neurocognitive performance by enhancing focus, visual acuity and readiness, and by promoting emotional regulation needed for peak performance. In concussed athletes and soldiers, concussions not only alter brain connectivity, but also alter cardiac functioning and impair cardiovascular performance upon exertion. Altered sympathetic and parasympathetic balance in the ANS has been postulated as a critical factor in refractory post concussive syndrome (PCS). This article will review both the pathological aspects of reduced HRV on athletic performance, as well as the cardiovascular and cerebrovascular components of concussion and PCS. Additionally, this article will review interventions with HRV biofeedback (HRV BFB) training as a promising and underutilized treatment for sports and military-related concussion. Finally, this article will review research and promising case studies pertaining to use of HRV BFB for enhancement of cognition and performance, with applicability to concussion rehabilitation. PMID:25165461

Heart rate variability interventions for concussion and rehabilitation.

PubMed

Conder, Robert L; Conder, Alanna A

2014-01-01

The study of heart rate variability (HRV) has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain). It is well-established that lack of HRV implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal HRV has been associated with good cardiovascular health, autonomic nervous system (ANS) control, emotional regulation, and enhanced neurocognitive processing. In addition to health benefits, optimal HRV has been shown to improve neurocognitive performance by enhancing focus, visual acuity and readiness, and by promoting emotional regulation needed for peak performance. In concussed athletes and soldiers, concussions not only alter brain connectivity, but also alter cardiac functioning and impair cardiovascular performance upon exertion. Altered sympathetic and parasympathetic balance in the ANS has been postulated as a critical factor in refractory post concussive syndrome (PCS). This article will review both the pathological aspects of reduced HRV on athletic performance, as well as the cardiovascular and cerebrovascular components of concussion and PCS. Additionally, this article will review interventions with HRV biofeedback (HRV BFB) training as a promising and underutilized treatment for sports and military-related concussion. Finally, this article will review research and promising case studies pertaining to use of HRV BFB for enhancement of cognition and performance, with applicability to concussion rehabilitation.

Optimal diabatic dynamics of Majorana-based quantum gates

NASA Astrophysics Data System (ADS)

Rahmani, Armin; Seradjeh, Babak; Franz, Marcel

2017-08-01

In topological quantum computing, unitary operations on qubits are performed by adiabatic braiding of non-Abelian quasiparticles, such as Majorana zero modes, and are protected from local environmental perturbations. In the adiabatic regime, with timescales set by the inverse gap of the system, the errors can be made arbitrarily small by performing the process more slowly. To enhance the performance of quantum information processing with Majorana zero modes, we apply the theory of optimal control to the diabatic dynamics of Majorana-based qubits. While we sacrifice complete topological protection, we impose constraints on the optimal protocol to take advantage of the nonlocal nature of topological information and increase the robustness of our gates. By using the Pontryagin's maximum principle, we show that robust equivalent gates to perfect adiabatic braiding can be implemented in finite times through optimal pulses. In our implementation, modifications to the device Hamiltonian are avoided. Focusing on thermally isolated systems, we study the effects of calibration errors and external white and 1 /f (pink) noise on Majorana-based gates. While a noise-induced antiadiabatic behavior, where a slower process creates more diabatic excitations, prohibits indefinite enhancement of the robustness of the adiabatic scheme, our fast optimal protocols exhibit remarkable stability to noise and have the potential to significantly enhance the practical performance of Majorana-based information processing.

Whole body heat stress increases motor cortical excitability and skill acquisition in humans.

PubMed

Littmann, Andrew E; Shields, Richard K

2016-02-01

Vigorous systemic exercise stimulates a cascade of molecular and cellular processes that enhance central nervous system (CNS) plasticity and performance. The influence of heat stress on CNS performance and learning is novel. We designed two experiments to determine whether passive heat stress (1) facilitated motor cortex excitability and (2) improved motor task acquisition compared to no heat stress. Motor evoked potentials (MEPs) from the first dorsal interosseus (FDI) were collected before and after 30 min of heat stress at 73 °C. A second cohort of subjects performed a motor learning task using the FDI either following heat or the no heat condition. Heat stress increased heart rate to 65% of age-predicted maximum. After heat, mean resting MEP amplitude increased 48% (p<0.05). MEP stimulus-response amplitudes did not differ according to stimulus intensity. In the second experiment, heat stress caused a significant decrease in absolute and variable error (p<0.05) during a novel movement task using the FDI. Passive environmental heat stress (1) increases motor cortical excitability, and (2) enhances performance in a motor skill acquisition task. Controlled heat stress may prime the CNS to enhance motor skill acquisition during rehabilitation. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Bilateral Impedance Control For Telemanipulators

NASA Technical Reports Server (NTRS)

Moore, Christopher L.

1993-01-01

Telemanipulator system includes master robot manipulated by human operator, and slave robot performing tasks at remote location. Two robots electronically coupled so slave robot moves in response to commands from master robot. Teleoperation greatly enhanced if forces acting on slave robot fed back to operator, giving operator feeling he or she manipulates remote environment directly. Main advantage of bilateral impedance control: enables arbitrary specification of desired performance characteristics for telemanipulator system. Relationship between force and position modulated at both ends of system to suit requirements of task.

Performance indicators for the efficiency analysis of urban drainage systems.

PubMed

Artina, S; Becciu, G; Maglionico, M; Paoletti, A; Sanfilippo, U

2005-01-01

Performance indicators implemented in a decision support system (DSS) for the technical, managerial and economic evaluation of urban drainage systems (UDS), called MOMA FD, are presented. Several kinds of information are collected and processed by MOMA FD to evaluate both present situation and future scenarios of development and enhancement. Particular interest is focused on the evaluation of the environmental impact, which is considered a very relevant factor in the decision making process to identify the priorities for UDS improvements.

When bad stress goes good: increased threat reactivity predicts improved category learning performance.

PubMed

Ell, Shawn W; Cosley, Brandon; McCoy, Shannon K

2011-02-01

The way in which we respond to everyday stressors can have a profound impact on cognitive functioning. Maladaptive stress responses in particular are generally associated with impaired cognitive performance. We argue, however, that the cognitive system mediating task performance is also a critical determinant of the stress-cognition relationship. Consistent with this prediction, we observed that stress reactivity consistent with a maladaptive, threat response differentially predicted performance on two categorization tasks. Increased threat reactivity predicted enhanced performance on an information-integration task (i.e., learning is thought to depend upon a procedural-based memory system), and a (nonsignificant) trend for impaired performance on a rule-based task (i.e., learning is thought to depend upon a hypothesis-testing system). These data suggest that it is critical to consider both variability in the stress response and variability in the cognitive system mediating task performance in order to fully understand the stress-cognition relationship.

An augmented-reality edge enhancement application for Google Glass.

PubMed

Hwang, Alex D; Peli, Eli

2014-08-01

Google Glass provides a platform that can be easily extended to include a vision enhancement tool. We have implemented an augmented vision system on Glass, which overlays enhanced edge information over the wearer's real-world view, to provide contrast-improved central vision to the Glass wearers. The enhanced central vision can be naturally integrated with scanning. Google Glass' camera lens distortions were corrected by using an image warping. Because the camera and virtual display are horizontally separated by 16 mm, and the camera aiming and virtual display projection angle are off by 10°, the warped camera image had to go through a series of three-dimensional transformations to minimize parallax errors before the final projection to the Glass' see-through virtual display. All image processes were implemented to achieve near real-time performance. The impacts of the contrast enhancements were measured for three normal-vision subjects, with and without a diffuser film to simulate vision loss. For all three subjects, significantly improved contrast sensitivity was achieved when the subjects used the edge enhancements with a diffuser film. The performance boost is limited by the Glass camera's performance. The authors assume that this accounts for why performance improvements were observed only with the diffuser filter condition (simulating low vision). Improvements were measured with simulated visual impairments. With the benefit of see-through augmented reality edge enhancement, natural visual scanning process is possible and suggests that the device may provide better visual function in a cosmetically and ergonomically attractive format for patients with macular degeneration.

Raman-based system for DNA sequencing-mapping and other separations

DOEpatents

Vo-Dinh, T.

1994-04-26

DNA sequencing and mapping are performed by using a Raman spectrometer with a surface enhanced Raman scattering (SERS) substrate to enhance the Raman signal. A SERS label is attached to a DNA fragment and then analyzed with the Raman spectrometer to identify the DNA fragment according to characteristics of the Raman spectrum generated. 11 figures.

Assessing performance enhancing tools: experiences with the open performance review and appraisal system (OPRAS) and expectations towards payment for performance (P4P) in the public health sector in Tanzania.

PubMed

Songstad, Nils Gunnar; Lindkvist, Ida; Moland, Karen Marie; Chimhutu, Victor; Blystad, Astrid

2012-09-10

Health workers' motivation is a key determinant of the quality of health services, and poor motivation has been found to be an obstacle to service delivery in many low-income countries. In order to increase the quality of service delivery in the public sector in Tanzania, the Open Performance Review and Appraisal System (OPRAS) has been implemented, and a new results-based payment system, Payment for performance (P4P) is introduced in the health sector. This article addresses health workers' experiences with OPRAS, expectations towards P4P and how lessons learned from OPRAS can assist in the implementation of P4P. The broader aim is to generate knowledge on health workers' motivation in low-income contexts. A qualitative study design has been employed to elicit data on health worker motivation at a general level and in relation to OPRAS and P4P in particular. Focus group discussions (FGDs) and in-depth interviews (IDIs) have been conducted with nursing staff, clinicians and administrators in the public health sector in a rural district in Tanzania. The study has an ethnographic backdrop based on earlier long-term fieldwork in Tanzania. Health workers evaluated OPRAS and P4P in terms of the benefits experienced or expected from complying with the tools. The study found a general reluctance towards OPRAS as health workers did not see OPRAS as leading to financial gains nor did it provide feedback on performance. Great expectations were expressed towards P4P due to its prospects of topping up salaries, but the links between the two performance enhancing tools were unclear. Health workers respond to performance enhancing tools based on whether the tools are found appropriate or yield any tangible benefits. The importance placed on salary and allowances forms the setting in which OPRAS operates. The expected addition to the salary through P4P has created a vigorous discourse among health workers attesting to the importance of the salary for motivation. Lessons learned from OPRAS can be utilized in the implementation of P4P and can enhance our knowledge on motivation and performance in the health services in low-income contexts such as Tanzania.

Assessing performance enhancing tools: experiences with the open performance review and appraisal system (OPRAS) and expectations towards payment for performance (P4P) in the public health sector in Tanzania

PubMed Central

2012-01-01

Background Health workers’ motivation is a key determinant of the quality of health services, and poor motivation has been found to be an obstacle to service delivery in many low-income countries. In order to increase the quality of service delivery in the public sector in Tanzania, the Open Performance Review and Appraisal System (OPRAS) has been implemented, and a new results-based payment system, Payment for performance (P4P) is introduced in the health sector. This article addresses health workers’ experiences with OPRAS, expectations towards P4P and how lessons learned from OPRAS can assist in the implementation of P4P. The broader aim is to generate knowledge on health workers’ motivation in low-income contexts. Methods A qualitative study design has been employed to elicit data on health worker motivation at a general level and in relation to OPRAS and P4P in particular. Focus group discussions (FGDs) and in-depth interviews (IDIs) have been conducted with nursing staff, clinicians and administrators in the public health sector in a rural district in Tanzania. The study has an ethnographic backdrop based on earlier long-term fieldwork in Tanzania. Results Health workers evaluated OPRAS and P4P in terms of the benefits experienced or expected from complying with the tools. The study found a general reluctance towards OPRAS as health workers did not see OPRAS as leading to financial gains nor did it provide feedback on performance. Great expectations were expressed towards P4P due to its prospects of topping up salaries, but the links between the two performance enhancing tools were unclear. Conclusions Health workers respond to performance enhancing tools based on whether the tools are found appropriate or yield any tangible benefits. The importance placed on salary and allowances forms the setting in which OPRAS operates. The expected addition to the salary through P4P has created a vigorous discourse among health workers attesting to the importance of the salary for motivation. Lessons learned from OPRAS can be utilized in the implementation of P4P and can enhance our knowledge on motivation and performance in the health services in low-income contexts such as Tanzania. PMID:22963317

Virtual fixtures as tools to enhance operator performance in telepresence environments

NASA Astrophysics Data System (ADS)

Rosenberg, Louis B.

1993-12-01

This paper introduces the notion of virtual fixtures for use in telepresence systems and presents an empirical study which demonstrates that such virtual fixtures can greatly enhance operator performance within remote environments. Just as tools and fixtures in the real world can enhance human performance by guiding manual operations, providing localizing references, and reducing the mental processing required to perform a task, virtual fixtures are computer generated percepts overlaid on top of the reflection of a remote workspace which can provide similar benefits. Like a ruler guiding a pencil in a real manipulation task, a virtual fixture overlaid on top of a remote workspace can act to reduce the mental processing required to perform a task, limit the workload of certain sensory modalities, and most of all allow precision and performance to exceed natural human abilities. Because such perceptual overlays are virtual constructions they can be diverse in modality, abstract in form, and custom tailored to individual task or user needs. This study investigates the potential of virtual fixtures by implementing simple combinations of haptic and auditory sensations as perceptual overlays during a standardized telemanipulation task.

Improving Rural Emergency Medical Services (EMS) through transportation system enhancements Phase II : project brief.

DOT National Transportation Integrated Search

2015-12-01

This study used the National EMS Information System (NEMSIS) South Dakota data to develop datadriven performance metrics for EMS. Researchers used the data for three tasks: geospatial analysis of EMS events, optimization of station locations, and ser...

Department of Revenue > Administrative Services

Science.gov Websites

implementation of process improvement and performance measurement systems that enhance the quality, productivity , certification, RSA's (Reimbursable Service Agreements), budget preparation, travel accounting, and professional

M855A1 Enhanced Performance Round (EPR) Media Day

DTIC Science & Technology

2011-05-04

Distribution is unlimited. Other requests shall be referred to the Office of the Project Manager for Maneuver Ammunition Systems, ATTN: SFAE-AMO-MAS- SETI ... SETI ,Picatinny,NJ,07806-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S...the Project Manager for Maneuver Ammunition Systems, ATTN: SFAE- AMO-MAS- SETI , Picatinny, NJ Distribution Statement A: Approved for Public Release

Space tug point design study. Volume 2: Operations, performance and requirements

NASA Technical Reports Server (NTRS)

1973-01-01

A design study to determine the configuration and characteristics of a space tug was conducted. Among the subjects analyzed in the study are: (1) flight and ground operations, (2) vehicle flight performance and performance enhancement techniques, (3) flight requirements, (4) basic design criteria, and (5) functional and procedural interface requirements between the tug and other systems.

The Resilience of the "Corporate" in Post-Corporate Teacher Appraisal: A Case Study from Mauritius

ERIC Educational Resources Information Center

Luchoomun, Dharmadeo

2007-01-01

This article seeks to replace the traditional and authoritative staff appraisal at a case-study school by a concept of performance management depicted as the performance enhancement and peer appraisal of teachers. It is achieved by elaborating an open system of performance management where teachers are empowered within the existing vertical…

A design for a new catalog manager and associated file management for the Land Analysis System (LAS)

NASA Technical Reports Server (NTRS)

Greenhagen, Cheryl

1986-01-01

Due to the larger number of different types of files used in an image processing system, a mechanism for file management beyond the bounds of typical operating systems is necessary. The Transportable Applications Executive (TAE) Catalog Manager was written to meet this need. Land Analysis System (LAS) users at the EROS Data Center (EDC) encountered some problems in using the TAE catalog manager, including catalog corruption, networking difficulties, and lack of a reliable tape storage and retrieval capability. These problems, coupled with the complexity of the TAE catalog manager, led to the decision to design a new file management system for LAS, tailored to the needs of the EDC user community. This design effort, which addressed catalog management, label services, associated data management, and enhancements to LAS applications, is described. The new file management design will provide many benefits including improved system integration, increased flexibility, enhanced reliability, enhanced portability, improved performance, and improved maintainability.

Performance enhancement for audio-visual speaker identification using dynamic facial muscle model.

PubMed

Asadpour, Vahid; Towhidkhah, Farzad; Homayounpour, Mohammad Mehdi

2006-10-01

Science of human identification using physiological characteristics or biometry has been of great concern in security systems. However, robust multimodal identification systems based on audio-visual information has not been thoroughly investigated yet. Therefore, the aim of this work to propose a model-based feature extraction method which employs physiological characteristics of facial muscles producing lip movements. This approach adopts the intrinsic properties of muscles such as viscosity, elasticity, and mass which are extracted from the dynamic lip model. These parameters are exclusively dependent on the neuro-muscular properties of speaker; consequently, imitation of valid speakers could be reduced to a large extent. These parameters are applied to a hidden Markov model (HMM) audio-visual identification system. In this work, a combination of audio and video features has been employed by adopting a multistream pseudo-synchronized HMM training method. Noise robust audio features such as Mel-frequency cepstral coefficients (MFCC), spectral subtraction (SS), and relative spectra perceptual linear prediction (J-RASTA-PLP) have been used to evaluate the performance of the multimodal system once efficient audio feature extraction methods have been utilized. The superior performance of the proposed system is demonstrated on a large multispeaker database of continuously spoken digits, along with a sentence that is phonetically rich. To evaluate the robustness of algorithms, some experiments were performed on genetically identical twins. Furthermore, changes in speaker voice were simulated with drug inhalation tests. In 3 dB signal to noise ratio (SNR), the dynamic muscle model improved the identification rate of the audio-visual system from 91 to 98%. Results on identical twins revealed that there was an apparent improvement on the performance for the dynamic muscle model-based system, in which the identification rate of the audio-visual system was enhanced from 87 to 96%.

Microwave remote plasma enhanced-atomic layer deposition system with multicusp confinement chamber

NASA Astrophysics Data System (ADS)

Dechana, A.; Thamboon, P.; Boonyawan, D.

2014-10-01

A microwave remote Plasma Enhanced-Atomic Layer Deposition system with multicusp confinement chamber is established at the Plasma and Beam Physics research facilities, Chiang Mai, Thailand. The system produces highly-reactive plasma species in order to enhance the deposition process of thin films. The addition of the multicusp magnetic fields further improves the plasma density and uniformity in the reaction chamber. Thus, the system is more favorable to temperature-sensitive substrates when heating becomes unwanted. Furthermore, the remote-plasma feature, which is generated via microwave power source, offers tunability of the plasma properties separately from the process. As a result, the system provides high flexibility in choice of materials and design experiments, particularly for low-temperature applications. Performance evaluations of the system were carried on coating experiments of Al2O3 layers onto a silicon wafer. The plasma characteristics in the chamber will be described. The resulted Al2O3 films—analyzed by Rutherford Backscattering Spectrometry in channeling mode and by X-ray Photoelectron Spectroscopy techniques—will be discussed.

Microwave remote plasma enhanced-atomic layer deposition system with multicusp confinement chamber.

PubMed

Dechana, A; Thamboon, P; Boonyawan, D

2014-10-01

A microwave remote Plasma Enhanced-Atomic Layer Deposition system with multicusp confinement chamber is established at the Plasma and Beam Physics research facilities, Chiang Mai, Thailand. The system produces highly-reactive plasma species in order to enhance the deposition process of thin films. The addition of the multicusp magnetic fields further improves the plasma density and uniformity in the reaction chamber. Thus, the system is more favorable to temperature-sensitive substrates when heating becomes unwanted. Furthermore, the remote-plasma feature, which is generated via microwave power source, offers tunability of the plasma properties separately from the process. As a result, the system provides high flexibility in choice of materials and design experiments, particularly for low-temperature applications. Performance evaluations of the system were carried on coating experiments of Al2O3 layers onto a silicon wafer. The plasma characteristics in the chamber will be described. The resulted Al2O3 films-analyzed by Rutherford Backscattering Spectrometry in channeling mode and by X-ray Photoelectron Spectroscopy techniques-will be discussed.

YUCSA: A CLIPS expert database system to monitor academic performance

NASA Technical Reports Server (NTRS)

Toptsis, Anestis A.; Ho, Frankie; Leindekar, Milton; Foon, Debra Low; Carbonaro, Mike

1991-01-01

The York University CLIPS Student Administrator (YUCSA), an expert database system implemented in C Language Integrated Processing System (CLIPS), for monitoring the academic performance of undergraduate students at York University, is discussed. The expert system component in the system has already been implemented for two major departments, and it is under testing and enhancement for more departments. Also, more elaborate user interfaces are under development. We describe the design and implementation of the system, problems encountered, and immediate future plans. The system has excellent maintainability and it is very efficient, taking less than one minute to complete an assessment of one student.

Atomic layer deposition of TiO2 shells on MoO3 nanobelts allowing enhanced lithium storage performance.

PubMed

Xie, Sanmu; Cao, Daxian; She, Yiyi; Wang, Hongkang; Shi, Jian-Wen; Leung, Micheal K H; Niu, Chunming

2018-06-26

Atomic layer deposition (ALD) of TiO2 shells on MoO3 nanobelts (denote as TiO2@MoO3) is realized using a home-made ALD system, which allows a controllable hydrolysis reaction of TiCl4-H2O on an atomic scale. When used as an anode material for lithium ion batteries, the TiO2@MoO3 electrode demonstrates much enhanced lithium storage performance including higher specific capacity, better cycling stability and rate capability.

An Integrated Design and Development System for Graphics Simulation.

ERIC Educational Resources Information Center

Richardson, J. Jeffrey

In the training of maintenance and operations technicians, three enhancements to a basic, straightforward, fixed-sequence simulation system can be useful. The primary advantage of the resultant system is that the principal object of simulation is the task to be performed, which includes both the planning knowledge and the equipment actions…

Enhancing Combat Survivability of Existing Unmanned Aircraft Systems

DTIC Science & Technology

2008-12-01

EL/K-1861 ...........................................................30 Figure 15. RQ-4 Global Hawk Communications Architecture Showing Various...ELINT Electronic Intelligence ESM Electronic Support Measures EW Electronic Warfare EO Electro-Optics FLIR Forward Looking Infrared GPS Global ...system performance (speed, altitude, maneuverability, and agility) reduces susceptibility through system design. The RQ-4 Global Hawk is designed to fly

Improving Student Learning: A Strategic Planning Framework for an Integrated Student Information System in Charlotte-Mecklenburg Schools

ERIC Educational Resources Information Center

Ngoma, Sylvester

2010-01-01

There is growing recognition that an electronic Student Information System (SIS) affects student learning. Given the strategic importance of SIS in supporting school administration and enhancing student performance, school districts are increasingly interested in acquiring the most effective and efficient Student Information Systems for their…

Teacher and School Leader Effectiveness: Lessons Learned from High-Performing Systems. Issue Brief

ERIC Educational Resources Information Center

Alliance for Excellent Education, 2011

2011-01-01

In an effort to find best practices in enhancing teacher effectiveness, the Alliance for Excellent Education (Alliance) and the Stanford Center for Opportunity Policy in Education (SCOPE) looked abroad at education systems that appear to have well-developed and effective systems for recruiting, preparing, developing, and retaining teachers and…

High security chaotic multiple access scheme for visible light communication systems with advanced encryption standard interleaving

NASA Astrophysics Data System (ADS)

Qiu, Junchao; Zhang, Lin; Li, Diyang; Liu, Xingcheng

2016-06-01

Chaotic sequences can be applied to realize multiple user access and improve the system security for a visible light communication (VLC) system. However, since the map patterns of chaotic sequences are usually well known, eavesdroppers can possibly derive the key parameters of chaotic sequences and subsequently retrieve the information. We design an advanced encryption standard (AES) interleaving aided multiple user access scheme to enhance the security of a chaotic code division multiple access-based visible light communication (C-CDMA-VLC) system. We propose to spread the information with chaotic sequences, and then the spread information is interleaved by an AES algorithm and transmitted over VLC channels. Since the computation complexity of performing inverse operations to deinterleave the information is high, the eavesdroppers in a high speed VLC system cannot retrieve the information in real time; thus, the system security will be enhanced. Moreover, we build a mathematical model for the AES-aided VLC system and derive the theoretical information leakage to analyze the system security. The simulations are performed over VLC channels, and the results demonstrate the effectiveness and high security of our presented AES interleaving aided chaotic CDMA-VLC system.

System-Level Radiation Hardening

NASA Technical Reports Server (NTRS)

Ladbury, Ray

2014-01-01

Although system-level radiation hardening can enable the use of high-performance components and enhance the capabilities of a spacecraft, hardening techniques can be costly and can compromise the very performance designers sought from the high-performance components. Moreover, such techniques often result in a complicated design, especially if several complex commercial microcircuits are used, each posing its own hardening challenges. The latter risk is particularly acute for Commercial-Off-The-Shelf components since high-performance parts (e.g. double-data-rate synchronous dynamic random access memories - DDR SDRAMs) may require other high-performance commercial parts (e.g. processors) to support their operation. For these reasons, it is essential that system-level radiation hardening be a coordinated effort, from setting requirements through testing up to and including validation.

Solar-powered compression-enhanced ejector air conditioner

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

Sokolov, M.; Hershgal, D.

1993-09-01

This article is an extension of an earlier investigation into the possibility of adaptation of the ejector refrigeration cycle to solar air-conditioning. In a previous work the ejector cycle has been proven a viable option only for a limited number of cases. These include systems with combined (heating, cooling, and hot water supply) loads where means for obtaining low condensing temperature are available. The purpose of this work is to extend the applicability of such systems by enhancing their efficiency and thereby improving their economical attractiveness. This is done by introducing the compression enhanced ejector system in which mechanical (rathermore » than thermal) energy is used to boost the pressure of the secondary stream into the ejector, Such a boost improves the performance of the whole system. Similar to the conventional ejector, the compression-enhanced ejector system utilizes practically the same hardware for solar heating during the winter and for solar cooling during the summer. Thus, it is capable of providing a year-round space air-conditioning. Optimization of the best combination in which the solar and refrigeration systems combine through the vapor generator working temperature is also presented.« less

Various On-Chip Sensors with Microfluidics for Biological Applications

PubMed Central

Lee, Hun; Xu, Linfeng; Koh, Domin; Nyayapathi, Nikhila; Oh, Kwang W.

2014-01-01

In this paper, we review recent advances in on-chip sensors integrated with microfluidics for biological applications. Since the 1990s, much research has concentrated on developing a sensing system using optical phenomena such as surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS) to improve the sensitivity of the device. The sensing performance can be significantly enhanced with the use of microfluidic chips to provide effective liquid manipulation and greater flexibility. We describe an optical image sensor with a simpler platform for better performance over a larger field of view (FOV) and greater depth of field (DOF). As a new trend, we review consumer electronics such as smart phones, tablets, Google glasses, etc. which are being incorporated in point-of-care (POC) testing systems. In addition, we discuss in detail the current optical sensing system integrated with a microfluidic chip. PMID:25222033

GUIDANCE DOCUMENT ON IMPLEMENTATION OF THE ...

EPA Pesticide Factsheets

The Agreement in Principle for the Stage 2 M-DBP Federal Advisory Committee contains a list of treatment processes and management practices for water systems to use in meeting additional Cryptosporidium treatment requirements under the LT2ESWTR. This list, termed the microbial toolbox, includes watershed control programs, alternative intake locations, pretreatment processes, additional filtration barriers, inactivation technologies, and enhanced plant performance. The intent of the microbial toolbox is to provide water systems with broad flexibility in selecting cost-effective LT2ESWTR compliance strategies. Moreover, the toolbox allows systems that currently provide additional pathogen barriers or that can demonstrate enhanced performance to receive additional Cryptosporidium treatment credit. Provide guidance to utilities with surface water supplies and to state drinking water programs on the use of different treatment technologies to reduce the level of Cryptosporidium in drinking water. Technologies included in the guidance manual may be used to achieve compliance with the requirements of the LT2ESWTR.

An on-line equivalent system identification scheme for adaptive control. Ph.D. Thesis - Stanford Univ.

NASA Technical Reports Server (NTRS)

Sliwa, S. M.

1984-01-01

A prime obstacle to the widespread use of adaptive control is the degradation of performance and possible instability resulting from the presence of unmodeled dynamics. The approach taken is to explicitly include the unstructured model uncertainty in the output error identification algorithm. The order of the compensator is successively increased by including identified modes. During this model building stage, heuristic rules are used to test for convergence prior to designing compensators. Additionally, the recursive identification algorithm as extended to multi-input, multi-output systems. Enhancements were also made to reduce the computational burden of an algorithm for obtaining minimal state space realizations from the inexact, multivariate transfer functions which result from the identification process. A number of potential adaptive control applications for this approach are illustrated using computer simulations. Results indicated that when speed of adaptation and plant stability are not critical, the proposed schemes converge to enhance system performance.

Stimulation-Based Control of Dynamic Brain Networks

PubMed Central

Pasqualetti, Fabio; Gu, Shi; Cieslak, Matthew

2016-01-01

The ability to modulate brain states using targeted stimulation is increasingly being employed to treat neurological disorders and to enhance human performance. Despite the growing interest in brain stimulation as a form of neuromodulation, much remains unknown about the network-level impact of these focal perturbations. To study the system wide impact of regional stimulation, we employ a data-driven computational model of nonlinear brain dynamics to systematically explore the effects of targeted stimulation. Validating predictions from network control theory, we uncover the relationship between regional controllability and the focal versus global impact of stimulation, and we relate these findings to differences in the underlying network architecture. Finally, by mapping brain regions to cognitive systems, we observe that the default mode system imparts large global change despite being highly constrained by structural connectivity. This work forms an important step towards the development of personalized stimulation protocols for medical treatment or performance enhancement. PMID:27611328

A CDMA system implementation with dimming control for visible light communication

NASA Astrophysics Data System (ADS)

Chen, Danyang; Wang, Jianping; Jin, Jianli; Lu, Huimin; Feng, Lifang

2018-04-01

Visible light communication (VLC), using solid-state lightings to transmit information, has become a complement technology to wireless radio communication. As a realistic multiple access scheme for VLC system, code division multiple access (CDMA) has attracted more and more attentions in recent years. In this paper, we address and implement an improved CDMA scheme for VLC system. The simulation results reveal that the improved CDMA scheme not only supports multi-users' transmission but also maintains dimming value at about 50% and enhances the system efficiency. It can also realize the flexible dimming control by adjusting some parameters of system structure, which rarely affects the system BER performance. A real-time experimental VLC system with improved CDMA scheme is performed based on field programmable gate array (FPGA), reaching a good BER performance.

Location-Enhanced Activity Recognition in Indoor Environments Using Off the Shelf Smart Watch Technology and BLE Beacons.

PubMed

Filippoupolitis, Avgoustinos; Oliff, William; Takand, Babak; Loukas, George

2017-05-27

Activity recognition in indoor spaces benefits context awareness and improves the efficiency of applications related to personalised health monitoring, building energy management, security and safety. The majority of activity recognition frameworks, however, employ a network of specialised building sensors or a network of body-worn sensors. As this approach suffers with respect to practicality, we propose the use of commercial off-the-shelf devices. In this work, we design and evaluate an activity recognition system composed of a smart watch, which is enhanced with location information coming from Bluetooth Low Energy (BLE) beacons. We evaluate the performance of this approach for a variety of activities performed in an indoor laboratory environment, using four supervised machine learning algorithms. Our experimental results indicate that our location-enhanced activity recognition system is able to reach a classification accuracy ranging from 92% to 100%, while without location information classification accuracy it can drop to as low as 50% in some cases, depending on the window size chosen for data segmentation.

Integrated health management and control of complex dynamical systems

NASA Astrophysics Data System (ADS)

Tolani, Devendra K.

2005-11-01

A comprehensive control and health management strategy for human-engineered complex dynamical systems is formulated for achieving high performance and reliability over a wide range of operation. Results from diverse research areas such as Probabilistic Robust Control (PRC), Damage Mitigating/Life Extending Control (DMC), Discrete Event Supervisory (DES) Control, Symbolic Time Series Analysis (STSA) and Health and Usage Monitoring System (HUMS) have been employed to achieve this goal. Continuous-domain control modules at the lower level are synthesized by PRC and DMC theories, whereas the upper-level supervision is based on DES control theory. In the PRC approach, by allowing different levels of risk under different flight conditions, the control system can achieve the desired trade off between stability robustness and nominal performance. In the DMC approach, component damage is incorporated in the control law to reduce the damage rate for enhanced structural durability. The DES controller monitors the system performance and, based on the mission requirements (e.g., performance metrics and level of damage mitigation), switches among various lower-level controllers. The core idea is to design a framework where the DES controller at the upper-level, mimics human intelligence and makes appropriate decisions to satisfy mission requirements, enhance system performance and structural durability. Recently developed tools in STSA have been used for anomaly detection and failure prognosis. The DMC deals with the usage monitoring or operational control part of health management, where as the issue of health monitoring is addressed by the anomaly detection tools. The proposed decision and control architecture has been validated on two test-beds, simulating the operations of rotorcraft dynamics and aircraft propulsion.

Role of self-sufficiency, productivity and diversification on the economic sustainability of farming systems with autochthonous sheep breeds in less favoured areas in Southern Europe.

PubMed

Ripoll-Bosch, R; Joy, M; Bernués, A

2014-08-01

Traditional mixed livestock cereal- and pasture-based sheep farming systems in Europe are threatened by intensification and specialisation processes. However, the intensification process does not always yield improved economic results or efficiency. This study involved a group of farmers that raised an autochthonous sheep breed (Ojinegra de Teruel) in an unfavourable area of North-East Spain. This study aimed to typify the farms and elucidate the existing links between economic performance and certain sustainability indicators (i.e. productivity, self-sufficiency and diversification). Information was obtained through direct interviews with 30 farms (73% of the farmers belonging to the breeders association). Interviews were conducted in 2009 and involved 32 indicators regarding farm structure, management and economic performance. With a principal component analysis, three factors were obtained explaining 77.9% of the original variance. This factors were named as inputs/self-sufficiency, which included the use of on-farm feeds, the amount of variable costs per ewe and economic performance; productivity, which included lamb productivity and economic autonomy; and productive orientation, which included the degree of specialisation in production. A cluster analysis identified the following four groups of farms: high-input intensive system; low-input self-sufficient system; specialised livestock system; and diversified crops-livestock system. In conclusion, despite the large variability between and within groups, the following factors that explain the economic profitability of farms were identified: (i) high feed self-sufficiency and low variable costs enhance the economic performance (per labour unit) of the farms; (ii) animal productivity reduces subsidy dependence, but does not necessarily imply better economic performance; and (iii) diversity of production enhances farm flexibility, but is not related to economic performance.

Cryogen-free heterodyne-enhanced mid-infrared Faraday rotation spectrometer

PubMed Central

Wang, Yin; Nikodem, Michal; Wysocki, Gerard

2013-01-01

A new detection method for Faraday rotation spectra of paramagnetic molecular species is presented. Near shot-noise limited performance in the mid-infrared is demonstrated using a heterodyne enhanced Faraday rotation spectroscopy (H-FRS) system without any cryogenic cooling. Theoretical analysis is performed to estimate the ultimate sensitivity to polarization rotation for both heterodyne and conventional FRS. Sensing of nitric oxide (NO) has been performed with an H-FRS system based on thermoelectrically cooled 5.24 μm quantum cascade laser (QCL) and a mercury-cadmium-telluride photodetector. The QCL relative intensity noise that dominates at low frequencies is largely avoided by performing the heterodyne detection in radio frequency range. H-FRS exhibits a total noise level of only 3.7 times the fundamental shot noise. The achieved sensitivity to polarization rotation of 1.8 × 10−8 rad/Hz1/2 is only 5.6 times higher than the ultimate theoretical sensitivity limit estimated for this system. The path- and bandwidth-normalized NO detection limit of 3.1 ppbv-m/Hz1/2 was achieved using the R(17/2) transition of NO at 1906.73 cm−1. PMID:23388967

Is More Better? - Night Vision Enhancement System's Pedestrian Warning Modes and Older Drivers.

PubMed

Brown, Timothy; He, Yefei; Roe, Cheryl; Schnell, Thomas

2010-01-01

Pedestrian fatalities as a result of vehicle collisions are much more likely to happen at night than during day time. Poor visibility due to darkness is believed to be one of the causes for the higher vehicle collision rate at night. Existing studies have shown that night vision enhancement systems (NVES) may improve recognition distance, but may increase drivers' workload. The use of automatic warnings (AW) may help minimize workload, improve performance, and increase safety. In this study, we used a driving simulator to examine performance differences of a NVES with six different configurations of warning cues, including: visual, auditory, tactile, auditory and visual, tactile and visual, and no warning. Older drivers between the ages of 65 and 74 participated in the study. An analysis based on the distance to pedestrian threat at the onset of braking response revealed that tactile and auditory warnings performed the best, while visual warnings performed the worst. When tactile or auditory warnings were presented in combination with visual warning, their effectiveness decreased. This result demonstrated that, contrary to general sense regarding warning systems, multi-modal warnings involving visual cues degraded the effectiveness of NVES for older drivers.

Dietary thiols in exercise: oxidative stress defence, exercise performance, and adaptation.

PubMed

McLeay, Yanita; Stannard, Stephen; Houltham, Stuart; Starck, Carlene

2017-01-01

Endurance athletes are susceptible to cellular damage initiated by excessive levels of aerobic exercise-produced reactive oxygen species (ROS). Whilst ROS can contribute to the onset of fatigue, there is increasing evidence that they play a crucial role in exercise adaptations. The use of antioxidant supplements such as vitamin C and E in athletes is common; however, their ability to enhance performance and facilitate recovery is controversial, with many studies suggesting a blunting of training adaptations with supplementation. The up-regulation of endogenous antioxidant systems brought about by exercise training allows for greater tolerance to subsequent ROS, thus, athletes may benefit from increasing these systems through dietary thiol donors. Recent work has shown supplementation with a cysteine donor (N-acetylcysteine; NAC) improves antioxidant capacity by augmenting glutathione levels and reducing markers of oxidative stress, as well as ergogenic potential through association with delayed fatigue in numerous experimental models. However, the use of this, and other thiol donors may have adverse physiological effects. A recent discovery for the use of a thiol donor food source, keratin, to potentially enhance endogenous antioxidants may have important implications for endurance athletes hoping to enhance performance and recovery without blunting training adaptations.

Improvement of signal to noise ratio of time domain mutliplexing fiber Bragg grating sensor network with Golay complementary codes

NASA Astrophysics Data System (ADS)

Elgaud, M. M.; Zan, M. S. D.; Abushagur, A. G.; Bakar, A. Ashrif A.

2017-07-01

This paper reports the employment of autocorrelation properties of Golay complementary codes (GCC) to enhance the performance of the time domain multiplexing fiber Bragg grating (TDM-FBG) sensing network. By encoding the light from laser with a stream of non-return-to-zero (NRZ) form of GCC and launching it into the sensing area that consists of the FBG sensors, we have found that the FBG signals can be decoded correctly with the autocorrelation calculations, confirming the successful demonstration of coded TDM-FBG sensor network. OptiGrating and OptiSystem simulators were used to design customized FBG sensors and perform the coded TDM-FBG sensor simulations, respectively. Results have substantiated the theoretical dependence of SNR enhancement on the code length of GCC, where the maximum SNR improvement of about 9 dB is achievable with the use of 256 bits of GCC compared to that of 4 bits case. Furthermore, the GCC has also extended the strain exposure up to 30% higher compared to the maximum of the conventional single pulse case. The employment of GCC in the TDM-FBG sensor system provides overall performance enhancement over the conventional single pulse case, under the same conditions.

Thomas D. Foust, Ph.D, P.E. | NREL

Science.gov Websites

-June 1997 Mechanical Systems Engineer, Nuclear Energy Program, DOE, August 1990-August 1992 Test Production," Science (2007) Heat Exchanger Performance Enhancement Methodologies, DOE Technical Report Separation Systems for Bioenergy Separations," presented at 24th Symposium on Biotechnology for Fuels

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

NASA Astrophysics Data System (ADS)

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

2018-06-01

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

Physical and digital simulations for IVA robotics

NASA Technical Reports Server (NTRS)

Hinman, Elaine; Workman, Gary L.

1992-01-01

Space based materials processing experiments can be enhanced through the use of IVA robotic systems. A program to determine requirements for the implementation of robotic systems in a microgravity environment and to develop some preliminary concepts for acceleration control of small, lightweight arms has been initiated with the development of physical and digital simulation capabilities. The physical simulation facilities incorporate a robotic workcell containing a Zymark Zymate II robot instrumented for acceleration measurements, which is able to perform materials transfer functions while flying on NASA's KC-135 aircraft during parabolic manuevers to simulate reduced gravity. Measurements of accelerations occurring during the reduced gravity periods will be used to characterize impacts of robotic accelerations in a microgravity environment in space. Digital simulations are being performed with TREETOPS, a NASA developed software package which is used for the dynamic analysis of systems with a tree topology. Extensive use of both simulation tools will enable the design of robotic systems with enhanced acceleration control for use in the space manufacturing environment.

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

NASA Astrophysics Data System (ADS)

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

2018-03-01

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

Real-time in-flight engine performance and health monitoring techniques for flight research application

NASA Technical Reports Server (NTRS)

Ray, Ronald J.; Hicks, John W.; Wichman, Keith D.

1991-01-01

Procedures for real time evaluation of the inflight health and performance of gas turbine engines and related systems were developed to enhance flight test safety and productivity. These techniques include the monitoring of the engine, the engine control system, thrust vectoring control system health, and the detection of engine stalls. Real time performance techniques were developed for the determination and display of inflight thrust and for aeroperformance drag polars. These new methods were successfully shown on various research aircraft at NASA-Dryden. The capability of NASA's Western Aeronautical Test Range and the advanced data acquisition systems were key factors for implementation and real time display of these methods.

Enhancing effects of nicotine and impairing effects of scopolamine on distinct aspects of performance in computerized attention and working memory tasks in marmoset monkeys.

PubMed

Spinelli, Simona; Ballard, Theresa; Feldon, Joram; Higgins, Guy A; Pryce, Christopher R

2006-08-01

With the CAmbridge Neuropsychological Test Automated Battery (CANTAB), computerized neuropsychological tasks can be presented on a touch-sensitive computer screen, and this system has been used to assess cognitive processes in neuropsychiatric patients, healthy volunteers, and species of non-human primate, primarily the rhesus macaque and common marmoset. Recently, we reported that the common marmoset, a small-bodied primate, can be trained to a high and stable level of performance on the CANTAB five-choice serial reaction time (5-CSRT) task of attention, and a novel task of working memory, the concurrent delayed match-to-position (CDMP) task. Here, in order to increase understanding of the specific cognitive demands of these tasks and the importance of acetylcholine to their performance, the effects of systemic delivery of the muscarinic receptor antagonist scopolamine and the nicotinic receptor agonist nicotine were studied. In the 5-CSRT task, nicotine enhanced performance in terms of increased sustained attention, whilst scopolamine led to increased omissions despite a high level of orientation to the correct stimulus location. In the CDMP task, scopolamine impaired performance at two stages of the task that differ moderately in terms of memory retention load but both of which are likely to require working memory, including interference-coping, abilities. Nicotine tended to enhance performance at the long-delay stage specifically but only against a background of relatively low baseline performance. These data are consistent with a dissociation of the roles of muscarinic and nicotinic cholinergic receptors in the regulation of both sustained attention and working memory in primates.

RDD-100 and the systems engineering process

NASA Technical Reports Server (NTRS)

Averill, Robert D.

1994-01-01

An effective systems engineering approach applied through the project life cycle can help Langley produce a better product. This paper demonstrates how an enhanced systems engineering process for in-house flight projects assures that each system will achieve its goals with quality performance and within planned budgets and schedules. This paper also describes how the systems engineering process can be used in combination with available software tools.

C3 generic workstation: Performance metrics and applications

NASA Technical Reports Server (NTRS)

Eddy, Douglas R.

1988-01-01

The large number of integrated dependent measures available on a command, control, and communications (C3) generic workstation under development are described. In this system, embedded communications tasks will manipulate workload to assess the effects of performance-enhancing drugs (sleep aids and decongestants), work/rest cycles, biocybernetics, and decision support systems on performance. Task performance accuracy and latency will be event coded for correlation with other measures of voice stress and physiological functioning. Sessions will be videotaped to score non-verbal communications. Physiological recordings include spectral analysis of EEG, ECG, vagal tone, and EOG. Subjective measurements include SWAT, fatigue, POMS and specialized self-report scales. The system will be used primarily to evaluate the effects on performance of drugs, work/rest cycles, and biocybernetic concepts. Performance assessment algorithms will also be developed, including those used with small teams. This system provides a tool for integrating and synchronizing behavioral and psychophysiological measures in a complex decision-making environment.

Very low cost real time histogram-based contrast enhancer utilizing fixed-point DSP processing

NASA Astrophysics Data System (ADS)

McCaffrey, Nathaniel J.; Pantuso, Francis P.

1998-03-01

A real time contrast enhancement system utilizing histogram- based algorithms has been developed to operate on standard composite video signals. This low-cost DSP based system is designed with fixed-point algorithms and an off-chip look up table (LUT) to reduce the cost considerably over other contemporary approaches. This paper describes several real- time contrast enhancing systems advanced at the Sarnoff Corporation for high-speed visible and infrared cameras. The fixed-point enhancer was derived from these high performance cameras. The enhancer digitizes analog video and spatially subsamples the stream to qualify the scene's luminance. Simultaneously, the video is streamed through a LUT that has been programmed with the previous calculation. Reducing division operations by subsampling reduces calculation- cycles and also allows the processor to be used with cameras of nominal resolutions. All values are written to the LUT during blanking so no frames are lost. The enhancer measures 13 cm X 6.4 cm X 3.2 cm, operates off 9 VAC and consumes 12 W. This processor is small and inexpensive enough to be mounted with field deployed security cameras and can be used for surveillance, video forensics and real- time medical imaging.

Performance and stability analysis of gas-injection enhanced natural circulation in heavy-liquid-metal-cooled systems

NASA Astrophysics Data System (ADS)

Yoo, Yeon-Jong

The purpose of this study is to investigate the performance and stability of the gas-injection enhanced natural circulation in heavy-liquid-metal-cooled systems. The target system is STAR-LM, which is a 400-MWt-class advanced lead-cooled fast reactor under development by Argonne National Laboratory and Oregon State University. The primary loop of STAR-LM relies on natural circulation to eliminate main circulation pumps for enhancement of passive safety. To significantly increase the natural circulation flow rate for the incorporation of potential future power uprates, the injection of noncondensable gas into the coolant above the core is envisioned ("gas lift pump"). Reliance upon gas-injection enhanced natural circulation raises the concern of flow instability due to the relatively high temperature change in the reactor core and the two-phase flow condition in the riser. For this study, the one-dimensional flow field equations were applied to each flow section and the mixture models of two-phase flow, i.e., both the homogeneous and drift-flux equilibrium models were used in the two-phase region of the riser. For the stability analysis, the linear perturbation technique based on the frequency-domain approach was used by employing the Nyquist stability criterion and a numerical root search method. It has been shown that the thermal power of the STAR-LM natural circulation system could be increased from 400 up to 1152 MW with gas injection under the limiting void fraction of 0.30 and limiting coolant velocity of 2.0 m/s from the steady-state performance analysis. As the result of the linear stability analysis, it has turned out that the STAR-LM natural circulation system would be stable even with gas injection. In addition, through the parametric study, it has been found that the thermal inertia effects of solid structures such as fuel rod and heat exchanger tube should be considered in the stability analysis model. The results of this study will be a part of the optimized stable design of the gas-injection enhanced natural circulation of STAR-LM with substantially improved power level and economical competitiveness. Furthermore, combined with the parametric study, this research could contribute a guideline for the design of other similar heavy-liquid-metal-cooled natural circulation systems with gas injection.

Enhanced photoelectrochemical performance of TiO2 nanotube arrays with coexisted Pt nanoparticles and Co-Pi cocatalysts

NASA Astrophysics Data System (ADS)

Li, Yanfang; Cao, Chang; Xie, Xinxin; Zhang, Li; Lin, Shiwei

2018-04-01

Highly-ordered TiO2 nanotube arrays (TNTAs) were prepared by electrochemical anodization. Cobalt-phosphate (Co-Pi) film fabricated by electrodeposition and Pt nanoparticles (Pt NPs) fabricated by photochemical reduction were decorated onto TNTAs to enhance the photoelectrochemical (PEC) performance together. The photocurrent density of the TNTAs/Co-Pi/Pt photoelectrode could reach 0.185 mA/cm2 at 1.23 V versus reversible hydrogen electrode under UV lamp illumination (1 mW/cm2), which is 2.65 times compared to that of the pure TNTAs photoelectrode. Electrochemistry impedance spectroscopy and Mott-Schottky analysis were conducted to explore the reasons for the enhancement of the PEC performance. Pt NPs could promote the reduction of Co(Ⅳ)-oxo intermediate to Co(II) or Co(Ⅲ) which facilitated the charge transfer in the PEC performance. The result provides a promising guideline to design a simple and efficient photoelectrode for the PEC water-splitting system.

PIPER: Performance Insight for Programmers and Exascale Runtimes: Guiding the Development of the Exascale Software Stack

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

Mellor-Crummey, John

The PIPER project set out to develop methodologies and software for measurement, analysis, attribution, and presentation of performance data for extreme-scale systems. Goals of the project were to support analysis of massive multi-scale parallelism, heterogeneous architectures, multi-faceted performance concerns, and to support both post-mortem performance analysis to identify program features that contribute to problematic performance and on-line performance analysis to drive adaptation. This final report summarizes the research and development activity at Rice University as part of the PIPER project. Producing a complete suite of performance tools for exascale platforms during the course of this project was impossible since bothmore » hardware and software for exascale systems is still a moving target. For that reason, the project focused broadly on the development of new techniques for measurement and analysis of performance on modern parallel architectures, enhancements to HPCToolkit’s software infrastructure to support our research goals or use on sophisticated applications, engaging developers of multithreaded runtimes to explore how support for tools should be integrated into their designs, engaging operating system developers with feature requests for enhanced monitoring support, engaging vendors with requests that they add hardware measure- ment capabilities and software interfaces needed by tools as they design new components of HPC platforms including processors, accelerators and networks, and finally collaborations with partners interested in using HPCToolkit to analyze and tune scalable parallel applications.« less

A Distributed Ambient Intelligence Based Multi-Agent System for Alzheimer Health Care

NASA Astrophysics Data System (ADS)

Tapia, Dante I.; RodríGuez, Sara; Corchado, Juan M.

This chapter presents ALZ-MAS (Alzheimer multi-agent system), an ambient intelligence (AmI)-based multi-agent system aimed at enhancing the assistance and health care for Alzheimer patients. The system makes use of several context-aware technologies that allow it to automatically obtain information from users and the environment in an evenly distributed way, focusing on the characteristics of ubiquity, awareness, intelligence, mobility, etc., all of which are concepts defined by AmI. ALZ-MAS makes use of a services oriented multi-agent architecture, called flexible user and services oriented multi-agent architecture, to distribute resources and enhance its performance. It is demonstrated that a SOA approach is adequate to build distributed and highly dynamic AmI-based multi-agent systems.

Reliability enhancement of common module systems

NASA Astrophysics Data System (ADS)

Schellenberger, Gisbert; Ruehlich, Ingo; Korf, Herbert; Petrie, Juergen J.; Muenter, Rolf

2004-08-01

Several thousands of 1st Gen IR Systems operated by Integral Stirling Cooler HD1033 are still in service worldwide. Replacing the HD 1033 Stirling by a Linear Drive Cooler will result in a significant reliability enhancement of these IR system of about a factor of three. These attempts had been unsuccessful in the past due to excessive EMI noise induced by the linear cooler compressor. So a main goal for such a development is the elimination of various EMI distortions in the IR system by EMI filtering and shielding. Additionally, the synchronization of the cooler power to the predominant scanning frequency of the IR system significantly improves the image quality. Technical details of the solution, MTTF data and performance data are described in detail.

Power system security enhancement through direct non-disruptive load control

NASA Astrophysics Data System (ADS)

Ramanathan, Badri Narayanan

The transition to a competitive market structure raises significant concerns regarding reliability of the power grid. A need to build tools for security assessment that produce operating limit boundaries for both static and dynamic contingencies is recognized. Besides, an increase in overall uncertainty in operating conditions makes corrective actions at times ineffective leaving the system vulnerable to instability. The tools that are in place for stability enhancement are mostly corrective and suffer from lack of robustness to operating condition changes. They often pose serious coordination challenges. With deregulation, there have also been ownership and responsibility issues associated with stability controls. However, the changing utility business model and the developments in enabling technologies such as two-way communication, metering, and control open up several new possibilities for power system security enhancement. This research proposes preventive modulation of selected loads through direct control for power system security enhancement. Two main contributions of this research are the following: development of an analysis framework and two conceptually different analysis approaches for load modulation to enhance oscillatory stability, and the development and study of algorithms for real-time modulation of thermostatic loads. The underlying analysis framework is based on the Structured Singular Value (SSV or mu) theory. Based on the above framework, two fundamentally different approaches towards analysis of the amount of load modulation for desired stability performance have been developed. Both the approaches have been tested on two different test systems: CIGRE Nordic test system and an equivalent of the Western Electric Coordinating Council test system. This research also develops algorithms for real-time modulation of thermostatic loads that use the results of the analysis. In line with some recent load management programs executed by utilities, two different algorithms based on dynamic programming are proposed for air-conditioner loads, while a decision-tree based algorithm is proposed for water-heater loads. An optimization framework has been developed employing the above algorithms. Monte Carlo simulations have been performed using this framework with the objective of studying the impact of different parameters and constraints on the effectiveness as well as the effect of control. The conclusions drawn from this research strongly advocate direct load control for stability enhancement from the perspectives of robustness and coordination, as well as economic viability and the developments towards availability of the institutional framework for load participation in providing system reliability services.

A Pirate's Life: A Model and a Metaphor for Learning.

ERIC Educational Resources Information Center

Solomon, David L.

2002-01-01

Discusses various ways in which context may be interpreted to enhance learning and performance; illustrates domains of learning using a hockey team as an example; and suggests implications for learning, performance, and instructional design. Highlights include an ecological systems model; and examples of individual development, team learning, and…

Thermodynamic analysis of a new dual evaporator CO2 transcritical refrigeration cycle

NASA Astrophysics Data System (ADS)

Abdellaoui, Ezzaalouni Yathreb; Kairouani, Lakdar Kairouani

2017-03-01

In this work, a new dual-evaporator CO2 transcritical refrigeration cycle with two ejectors is proposed. In this new system, we proposed to recover the lost energy of condensation coming off the gas cooler and operate the refrigeration cycle ejector free and enhance the system performance and obtain dual-temperature refrigeration simultaneously. The effects of some key parameters on the thermodynamic performance of the modified cycle are theoretically investigated based on energetic and exergetic analysis. The simulation results for the modified cycle indicate more effective system performance improvement than the single ejector in the CO2 vapor compression cycle using ejector as an expander ranging up to 46%. The exergetic analysis for this system is made. The performance characteristics of the proposed cycle show its promise in dual-evaporator refrigeration system.

Aircraft Flight Envelope Determination using Upset Detection and Physical Modeling Methods

NASA Technical Reports Server (NTRS)

Keller, Jeffrey D.; McKillip, Robert M. Jr.; Kim, Singwan

2009-01-01

The development of flight control systems to enhance aircraft safety during periods of vehicle impairment or degraded operations has been the focus of extensive work in recent years. Conditions adversely affecting aircraft flight operations and safety may result from a number of causes, including environmental disturbances, degraded flight operations, and aerodynamic upsets. To enhance the effectiveness of adaptive and envelope limiting controls systems, it is desirable to examine methods for identifying the occurrence of anomalous conditions and for assessing the impact of these conditions on the aircraft operational limits. This paper describes initial work performed toward this end, examining the use of fault detection methods applied to the aircraft for aerodynamic performance degradation identification and model-based methods for envelope prediction. Results are presented in which a model-based fault detection filter is applied to the identification of aircraft control surface and stall departure failures/upsets. This application is supported by a distributed loading aerodynamics formulation for the flight dynamics system reference model. Extensions for estimating the flight envelope due to generalized aerodynamic performance degradation are also described.

Brief Report: The Relationship between Visual Acuity, the Embedded Figures Test and Systemizing in Autism Spectrum Disorders

ERIC Educational Resources Information Center

Brosnan, Mark J.; Gwilliam, Lucy R.; Walker, Ian

2012-01-01

Enhanced performance upon the Embedded Figures Test (EFT) in individuals with autism spectrum disorder (ASD) has informed psychological theories of the non-social aspects that characterise ASD. The Extreme Male Brain theory of autism proposes that enhanced visual acuity underpins greater attention to detail (assessed by the EFT) which is a…

Multi-Image Registration for an Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn; Rahman, Zia-Ur; Jobson, Daniel; Woodell, Glenn

2002-01-01

An Enhanced Vision System (EVS) utilizing multi-sensor image fusion is currently under development at the NASA Langley Research Center. The EVS will provide enhanced images of the flight environment to assist pilots in poor visibility conditions. Multi-spectral images obtained from a short wave infrared (SWIR), a long wave infrared (LWIR), and a color visible band CCD camera, are enhanced and fused using the Retinex algorithm. The images from the different sensors do not have a uniform data structure: the three sensors not only operate at different wavelengths, but they also have different spatial resolutions, optical fields of view (FOV), and bore-sighting inaccuracies. Thus, in order to perform image fusion, the images must first be co-registered. Image registration is the task of aligning images taken at different times, from different sensors, or from different viewpoints, so that all corresponding points in the images match. In this paper, we present two methods for registering multiple multi-spectral images. The first method performs registration using sensor specifications to match the FOVs and resolutions directly through image resampling. In the second method, registration is obtained through geometric correction based on a spatial transformation defined by user selected control points and regression analysis.

Indocyanine green fluorescence-guided parathyroidectomy for primary hyperparathyroidism.

PubMed

DeLong, Jonathan C; Ward, Erin P; Lwin, Thinzar M; Brumund, Kevin T; Kelly, Kaitlyn J; Horgan, Santiago; Bouvet, Michael

2018-02-01

Our aim was to evaluate the ease and utility of using indocyanine green fluorescence angiography for intraoperative localization of the parathyroid glands. Indocyanine green fluorescence angiography was performed during 60 parathyroidectomies for primary hyperparathyroidism during a 22-month period. Indocyanine green was administered intravenously to guide operative navigation using a commercially available fluorescence imaging system. Video files were graded by 3 independent surgeons for strength of enhancement using an adapted numeric scoring system. There were 46 (77%) female patients and 14 (23%) male patients whose ages ranged from 17 to 87 (average 60) years old. Of the 60 patients, 43 (71.6%) showed strong enhancement, 13 (21.7%) demonstrated mild to moderate vascular enhancement, and 4 (6.7%) exhibited little or no vascular enhancement. Of the 54 patients who had a preoperative sestamibi scan, a parathyroid adenoma was identified in 36, while 18 failed to localize. Of the 18 patients who failed to localize, all 18 patients (100%) had an adenoma that fluoresced on indocyanine green imaging. The operations were performed safely with minimal blood loss and short operative times. Indocyanine green angiography has the potential to assist surgeons in identifying parathyroid glands rapidly with minimal risk. Copyright © 2017 Elsevier Inc. All rights reserved.

Mass transport enhancement in redox flow batteries with corrugated fluidic networks

NASA Astrophysics Data System (ADS)

Lisboa, Kleber Marques; Marschewski, Julian; Ebejer, Neil; Ruch, Patrick; Cotta, Renato Machado; Michel, Bruno; Poulikakos, Dimos

2017-08-01

We propose a facile, novel concept of mass transfer enhancement in flow batteries based on electrolyte guidance in rationally designed corrugated channel systems. The proposed fluidic networks employ periodic throttling of the flow to optimally deflect the electrolytes into the porous electrode, targeting enhancement of the electrolyte-electrode interaction. Theoretical analysis is conducted with channels in the form of trapezoidal waves, confirming and detailing the mass transport enhancement mechanism. In dilute concentration experiments with an alkaline quinone redox chemistry, a scaling of the limiting current with Re0.74 is identified, which compares favourably against the Re0.33 scaling typical of diffusion-limited laminar processes. Experimental IR-corrected polarization curves are presented for high concentration conditions, and a significant performance improvement is observed with the narrowing of the nozzles. The adverse effects of periodic throttling on the pumping power are compared with the benefits in terms of power density, and an improvement of up to 102% in net power density is obtained in comparison with the flow-by case employing straight parallel channels. The proposed novel concept of corrugated fluidic networks comes with facile fabrication and contributes to the improvement of the transport characteristics and overall performance of redox flow battery systems.

Assessing the Impact of Development Disruptions and Dependencies in Analysis of Alternatives of System-of-Systems

DTIC Science & Technology

2012-12-31

WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Purdue University,West Lafayette,IN,47907 8. PERFORMING ORGANIZATION REPORT...operational independence, yet, must work cohesively to achieve an overarching set of capabilities. Current guidelines set forth by the Department of Defense...architectures; these methods will be further matured and enhanced in follow-up research work under RT-44. 15. SUBJECT TERMS 16. SECURITY

Sea wind parameters retrieval using Y-configured Doppler navigation system data. Performance and accuracy

NASA Astrophysics Data System (ADS)

Khachaturian, A. B.; Nekrasov, A. V.; Bogachev, M. I.

2018-05-01

The authors report the results of the computer simulations of the performance and accuracy of the sea wind speed and direction retrieval. The analyzed measurements over the sea surface are made by the airborne microwave Doppler navigation system (DNS) with three Y-configured beams operated as a scatterometer enhancing its functionality. Single- and double-stage wind measurement procedures are proposed and recommendations for their implementation are described.

Mapping brain functional alterations in betel-quid chewers using resting-state fMRI and network analysis.

PubMed

Weng, Jun-Cheng; Chou, Yu-Syuan; Huang, Guo-Joe; Tyan, Yeu-Sheng; Ho, Ming-Chou

2018-04-01

The World Health Organization regards betel quid (BQ) as a human carcinogen, and DSM-IV and ICD-10 dependence symptoms may develop with its heavy use. BQ's possible effects of an enhanced reward system and disrupted inhibitory control may increase the likelihood of habitual substance use. The current study aimed to employ resting-state fMRI to examine the hypothesized enhanced reward system (e.g., the basal forebrain system) and disrupted inhibitory control (e.g., the prefrontal system) in BQ chewers. The current study recruited three groups of 48 male participants: 16 BQ chewers, 15 tobacco- and alcohol-user controls, and 17 healthy controls. We used functional connectivity (FC), mean fractional amplitude of low-frequency fluctuations (mfALFF), and mean regional homogeneity (mReHo) to evaluate functional alternations in BQ chewers. Graph theoretical analysis (GTA) and network-based statistical (NBS) analysis were also performed to identify the functional network differences among the three groups. Our hypothesis was partially supported: the enhanced reward system for the BQ chewers (e.g., habitual drug-seeking behavior) was supported; however, their inhibitory control was relatively preserved. In addition, we reported that the BQ chewers may have enhanced visuospatial processing and decreased local segregation. The current results (showing an enhanced reward system in the chewers) provided the clinicians with important insight for the future development of an effective abstinence treatment.

Experimental Studies on the Effect of Enhanced Thermal Conductivity of SiC+Water Nanofluid in the Performance of Small Scale Solar Parabolic Dish Receiver

NASA Astrophysics Data System (ADS)

Rajendran, D. R.; Sundaram, E. Ganapathy; Jawahar, P.

In this experimental study, exergy efficiencies of water and SiC+water nanofluid, prepared from 50nm particle size and 1% of volume fraction were compared based on the effect of thermal conductivities by a dish reflector receiver system. The average temperature difference between the receiver walls and heat transfer fluids have been studied to understand the thermal performance of the system with respect to the important properties of thermal conductivities and specific heat capacities. The enhanced thermal conductivity of 0.800115W/mK with the Keff/Kb ratio of 1.1759 was determined by the Koo and Kleinstreuer correlation which is considering both the Maxwell correlation and Brownian motion. The attained higher average exergy efficiencies for water and SiC+water nanofluid are 21.08% and 37.06.%, respectively with the enhanced nanofluid exergy efficiency of 75.80% than that of water at the flow rate of 0.5lpm. The result also shows that the system with SiC+water nanofluid produced higher exergy efficiency, because the rates of energy and exergy carried by the nanofluid are 0.2378kW and 0.7593kW higher than that of water for all the flow rates except at 0.2lpm, due to the enhanced thermal conductivity of the nanofluid.

The benefits of cholinergic enhancement during perceptual learning are long-lasting

PubMed Central

Rokem, Ariel; Silver, Michael A.

2013-01-01

The neurotransmitter acetylcholine (ACh) regulates many aspects of cognition, including attention and memory. Previous research in animal models has shown that plasticity in sensory systems often depends on the behavioral relevance of a stimulus and/or task. However, experimentally increasing ACh release in the cortex can result in experience-dependent plasticity, even in the absence of behavioral relevance. In humans, the pharmacological enhancement of ACh transmission by administration of the cholinesterase inhibitor donepezil during performance of a perceptual task increases the magnitude of perceptual learning (PL) and its specificity to physical parameters of the stimuli used for training. Behavioral effects of PL have previously been shown to persist for many months. In the present study, we tested whether enhancement of PL by donepezil is also long-lasting. Healthy human subjects were trained on a motion direction discrimination task during cholinergic enhancement, and follow-up testing was performed 5–15 months after the end of training and without additional drug administration. Increases in performance associated with training under donepezil were evident in follow-up retesting, indicating that cholinergic enhancement has beneficial long-term effects on PL. These findings suggest that cholinergic enhancement of training procedures used to treat clinical disorders should improve long-term outcomes of these procedures. PMID:23755006

Diagnosing Parkinson's Diseases Using Fuzzy Neural System

PubMed Central

Abiyev, Rahib H.; Abizade, Sanan

2016-01-01

This study presents the design of the recognition system that will discriminate between healthy people and people with Parkinson's disease. A diagnosing of Parkinson's diseases is performed using fusion of the fuzzy system and neural networks. The structure and learning algorithms of the proposed fuzzy neural system (FNS) are presented. The approach described in this paper allows enhancing the capability of the designed system and efficiently distinguishing healthy individuals. It was proved through simulation of the system that has been performed using data obtained from UCI machine learning repository. A comparative study was carried out and the simulation results demonstrated that the proposed fuzzy neural system improves the recognition rate of the designed system. PMID:26881009

Time-varying delays compensation algorithm for powertrain active damping of an electrified vehicle equipped with an axle motor during regenerative braking

NASA Astrophysics Data System (ADS)

Zhang, Junzhi; Li, Yutong; Lv, Chen; Gou, Jinfang; Yuan, Ye

2017-03-01

The flexibility of the electrified powertrain system elicits a negative effect upon the cooperative control performance between regenerative and hydraulic braking and the active damping control performance. Meanwhile, the connections among sensors, controllers, and actuators are realized via network communication, i.e., controller area network (CAN), that introduces time-varying delays and deteriorates the control performances of the closed-loop control systems. As such, the goal of this paper is to develop a control algorithm to cope with all these challenges. To this end, the models of the stochastic network induced time-varying delays, based on a real in-vehicle network topology and on a flexible electrified powertrain, were firstly built. In order to further enhance the control performances of active damping and cooperative control of regenerative and hydraulic braking, the time-varying delays compensation algorithm for the electrified powertrain active damping during regenerative braking was developed based on a predictive scheme. The augmented system is constructed and the H∞ performance is analyzed. Based on this analysis, the control gains are derived by solving a nonlinear minimization problem. The simulations and hardware-in-loop (HIL) tests were carried out to validate the effectiveness of the developed algorithm. The test results show that the active damping and cooperative control performances are enhanced significantly.

Design of the computerized 3D endoscopic imaging system for delicate endoscopic surgery.

PubMed

Song, Chul-Gyu; Kang, Jin U

2011-02-01

This paper describes a 3D endoscopic video system designed to improve visualization and enhance the ability of the surgeon to perform delicate endoscopic surgery. In a comparison of the polarized and conventional electric shutter-type stereo imaging systems, the former was found to be superior in terms of both accuracy and speed for suturing and for the loop pass test. Among the groups performing loop passing and suturing, there was no significant difference in the task performance between the 2D and 3D modes, however, suturing was performed 15% (p < 0.05) faster in 3D mode by both groups. The results of our experiments show that the proposed 3D endoscopic system has a sufficiently wide viewing angle and zone for multi-viewing.

Enhancing the performance of coherent OTDR systems with polarization diversity complementary codes.

PubMed

Dorize, Christian; Awwad, Elie

2018-05-14

Monitoring the optical phase change in a fiber enables a wide range of applications where fast phase variations are induced by acoustic signals or by vibrations in general. However, the quality of the estimated fiber response strongly depends on the method used to modulate the light sent to the fiber and capture the variations of the optical field. In this paper, we show that distributed optical fiber sensing systems can advantageously exploit techniques from the telecommunication domain, as those used in coherent optical transmission, to enhance their performance in detecting mechanical events, while jointly offering a simpler setup than widespread pulse-cloning or spectral-sweep based schemes with acousto-optic modulators. We periodically capture an overall fiber Jones matrix estimate thanks to a novel probing technique using two mutually orthogonal complementary (Golay) pairs of binary sequences applied simultaneously in phase and quadrature on two orthogonal polarization states. A perfect channel response estimation of the sensor array is achieved, subject to conditions detailed in the paper, thus enhancing the sensitivity and bandwidth of coherent ϕ-OTDR systems. High sensitivity, linear response, and bandwidth coverage up to 18 kHz are demonstrated with a sensor array composed of 10 fiber Bragg gratings (FBGs).

Enhancing the performance of coherent OTDR systems with polarization diversity complementary codes

NASA Astrophysics Data System (ADS)

Dorize, Christian; Awwad, Elie

2018-05-01

Monitoring the optical phase change in a fiber enables a wide range of applications where fast phase variations are induced by acoustic signals or vibrations in general. However, the quality of the estimated fiber response strongly depends on the method used to modulate the light sent to the fiber and capture the variations of the optical field. In this paper, we show that distributed optical fiber sensing systems can advantageously exploit techniques from the telecommunication domain, as those used in coherent optical transmission, to enhance their performance in detecting mechanical events, while jointly offering a simpler setup than widespread pulse-cloning or spectral-sweep based schemes with acousto-optic modulators. We periodically capture an overall fiber Jones matrix estimate thanks to a novel probing technique using two mutually orthogonal complementary (Golay) pairs of binary sequences applied simultaneously in phase and quadrature on two orthogonal polarization states. A perfect channel response estimation of the sensor array is achieved, subject to conditions detailed in the paper, thus enhancing the sensitivity and bandwidth of coherent phase-OTDR systems. High sensitivity, linear response, and bandwidth coverage up to 18 kHz are demonstrated with a sensor array composed of 10 fiber Bragg gratings (FBGs).

Synthesis of BiVO4-GO-PVDF nanocomposite: An excellent, newly designed material for high photocatalytic activity towards organic dye degradation by tuning band gap energies

NASA Astrophysics Data System (ADS)

Biswas, Md Rokon Ud Dowla; Oh, Won-Chun

2018-06-01

BiVO4-GO-PVDF (PVDF = Polyvinylidene Difluoride) photocatalyst is successfully synthesized by ultrasonication method and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques. Morphology of BiVO4-GO-PVDF looks like a human embryo embedded inside an amniotic sac. Photocatalytic performance of BiVO4-GO-PVDF for decolorization of methylene blue is investigated. BiVO4-GO-PVDF system reveals enhanced photocatalytic activity degradation of methylene blue (MB), Rhodamine B (RhB) & Safranin-O (SO) in water under visible light irradiation as compared to the pure BiVO4 catalyst, BiVO4 & PTFE decorated on the graphene sheet. The experimental result reveals that the covering of graphene sheets in this composite catalyst enhances photocatalytic performance under visible light. This enhanced activity is mainly attributed to effective quenching of the photogenerated electron-hole pairs confirmed by photoluminescence spectra. Trapping experiments of radicals and holes were conducted to detect reactive species generated in the photocatalytic system, experimental results revealed that direct hole oxidation reaction is obviously dominant during photocatalytic reactions on the BiVO4-GO-PVDF system.

Enhancing light-harvesting power with coherent vibrational interactions: A quantum heat engine picture

NASA Astrophysics Data System (ADS)

Killoran, N.; Huelga, S. F.; Plenio, M. B.

2015-10-01

Recent evidence suggests that quantum effects may have functional importance in biological light-harvesting systems. Along with delocalized electronic excitations, it is now suspected that quantum coherent interactions with certain near-resonant vibrations may contribute to light-harvesting performance. However, the actual quantum advantage offered by such coherent vibrational interactions has not yet been established. We investigate a quantum design principle, whereby coherent exchange of single energy quanta between electronic and vibrational degrees of freedom can enhance a light-harvesting system's power above what is possible by thermal mechanisms alone. We present a prototype quantum heat engine which cleanly illustrates this quantum design principle and quantifies its quantum advantage using thermodynamic measures of performance. We also demonstrate the principle's relevance in parameter regimes connected to natural light-harvesting structures.

Buffered coscheduling for parallel programming and enhanced fault tolerance

DOEpatents

Petrini, Fabrizio [Los Alamos, NM; Feng, Wu-chun [Los Alamos, NM

2006-01-31

A computer implemented method schedules processor jobs on a network of parallel machine processors or distributed system processors. Control information communications generated by each process performed by each processor during a defined time interval is accumulated in buffers, where adjacent time intervals are separated by strobe intervals for a global exchange of control information. A global exchange of the control information communications at the end of each defined time interval is performed during an intervening strobe interval so that each processor is informed by all of the other processors of the number of incoming jobs to be received by each processor in a subsequent time interval. The buffered coscheduling method of this invention also enhances the fault tolerance of a network of parallel machine processors or distributed system processors

Method and apparatus for enhancing reactor air-cooling system performance

DOEpatents

Hunsbedt, Anstein

1996-01-01

An enhanced decay heat removal system for removing heat from the inert gas-filled gap space between the reactor vessel and the containment vessel of a liquid metal-cooled nuclear reactor. Multiple cooling ducts in flow communication with the inert gas-filled gap space are incorporated to provide multiple flow paths for the inert gas to circulate to heat exchangers which remove heat from the inert gas, thereby introducing natural convection flows in the inert gas. The inert gas in turn absorbs heat directly from the reactor vessel by natural convection heat transfer.

Ceramic membrane ultrafiltration of natural surface water with ultrasound enhanced backwashing.

PubMed

Boley, A; Narasimhan, K; Kieninger, M; Müller, W-R

2010-01-01

Ultrafiltration membrane cleaning with ultrasound enhanced backwashing was investigated with two ceramic membrane systems in parallel. One of them was subjected to ultrasound during backwashing, the other acted as a reference system. The feed water was directly taken from a creek with a sedimentation process as only pre-treatment. The cleaning performance was improved with ultrasound but after 3 weeks of operation damages occurred on the membranes. These effects were studied with online measurements of flux, trans-membrane-pressure and temperature, but also with integrity tests, turbidity measurements and visual examination.

A tool to enhance occupational therapy reasoning from ICF perspective: The Hasselt Occupational Performance Profile (H-OPP).

PubMed

Ghysels, R; Vanroye, E; Westhovens, M; Spooren, A

2017-03-01

In order to enhance occupational therapy reasoning in clinical practice, different elements such as client-centred approach, evidence-based care and interdisciplinary work should be taken into account, but is a challenge. To describe the development of the digital Hasselt Occupational Performance Profile (H-OPP © ) that enhances occupational therapy reasoning from ICF perspective. A participative qualitative design was used to create the H-OPP © in an iterative way in which occupational therapy lectures, ICF experts, students and occupational therapists in the field were involved. After linking occupational therapy terminology to the ICF, different stages of the H-OPP were identified and elaborated with main features: generating an occupational performance profile based on inventarization of problems and possibilities, formulating an occupational performance diagnosis and enabling to create an intervention plan. In all stages, both the perspectives of the client and the occupational therapist were taken into account. To increase practical use, the tool was further elaborated and digitalized. The H-OPP © is a digital coach that guides and facilitates professional reasoning in (novice) occupational therapists. It augments involvement of the client system. Furthermore, it enhances interdisciplinary communication and evidence-based care.

Autonomic Nervous System in Paralympic Athletes with Spinal Cord Injury.

PubMed

Walter, Matthias; Krassioukov, Andrei V

2018-05-01

Individuals sustaining a spinal cord injury (SCI) frequently suffer from sensorimotor and autonomic impairment. Damage to the autonomic nervous system results in cardiovascular, respiratory, bladder, bowel, and sexual dysfunctions, as well as temperature dysregulation. These complications not only impede quality of life, but also affect athletic performance of individuals with SCI. This article summarizes existing evidence on how damage to the spinal cord affects the autonomic nervous system and impacts the performance in athletes with SCI. Also discussed are frequently used performance-enhancing strategies, with a special focus on their legal aspect and implication on the athletes' health. Copyright © 2018 Elsevier Inc. All rights reserved.

Enhanced Energy Localization in Hyperthermia Treatment Based on Hybrid Electromagnetic and Ultrasonic System: Proof of Concept with Numerical Simulations.

PubMed

Nizam-Uddin, N; Elshafiey, Ibrahim

2017-01-01

This paper proposes a hybrid hyperthermia treatment system, utilizing two noninvasive modalities for treating brain tumors. The proposed system depends on focusing electromagnetic (EM) and ultrasound (US) energies. The EM hyperthermia subsystem enhances energy localization by incorporating a multichannel wideband setting and coherent-phased-array technique. A genetic algorithm based optimization tool is developed to enhance the specific absorption rate (SAR) distribution by reducing hotspots and maximizing energy deposition at tumor regions. The treatment performance is also enhanced by augmenting an ultrasonic subsystem to allow focused energy deposition into deep tumors. The therapeutic faculty of ultrasonic energy is assessed by examining the control of mechanical alignment of transducer array elements. A time reversal (TR) approach is then investigated to address challenges in energy focus in both subsystems. Simulation results of the synergetic effect of both modalities assuming a simplified model of human head phantom demonstrate the feasibility of the proposed hybrid technique as a noninvasive tool for thermal treatment of brain tumors.

Enhanced Energy Localization in Hyperthermia Treatment Based on Hybrid Electromagnetic and Ultrasonic System: Proof of Concept with Numerical Simulations

PubMed Central

Elshafiey, Ibrahim

2017-01-01

This paper proposes a hybrid hyperthermia treatment system, utilizing two noninvasive modalities for treating brain tumors. The proposed system depends on focusing electromagnetic (EM) and ultrasound (US) energies. The EM hyperthermia subsystem enhances energy localization by incorporating a multichannel wideband setting and coherent-phased-array technique. A genetic algorithm based optimization tool is developed to enhance the specific absorption rate (SAR) distribution by reducing hotspots and maximizing energy deposition at tumor regions. The treatment performance is also enhanced by augmenting an ultrasonic subsystem to allow focused energy deposition into deep tumors. The therapeutic faculty of ultrasonic energy is assessed by examining the control of mechanical alignment of transducer array elements. A time reversal (TR) approach is then investigated to address challenges in energy focus in both subsystems. Simulation results of the synergetic effect of both modalities assuming a simplified model of human head phantom demonstrate the feasibility of the proposed hybrid technique as a noninvasive tool for thermal treatment of brain tumors. PMID:28840125

The Smart Power Lab at the Energy Systems Integration Facility

ScienceCinema

Christensen, Dane; Sparn, Bethany; Hannegan, Brian

2018-05-11

Watch how NREL researchers are using the Smart Power Laboratory at the Energy Systems Integration Facility (ESIF) to develop technologies that will help the "smart homes" of the future perform efficiently and communicate effectively with the electricity grid while enhancing occupants' comfort and convenience.

The Smart Power Lab at the Energy Systems Integration Facility

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

Christensen, Dane; Sparn, Bethany; Hannegan, Brian

Watch how NREL researchers are using the Smart Power Laboratory at the Energy Systems Integration Facility (ESIF) to develop technologies that will help the "smart homes" of the future perform efficiently and communicate effectively with the electricity grid while enhancing occupants' comfort and convenience.

Close-form expression of one-tap normalized LMS carrier phase recovery in optical communication systems

NASA Astrophysics Data System (ADS)

Xu, Tianhua; Jacobsen, Gunnar; Popov, Sergei; Li, Jie; Liu, Tiegen; Zhang, Yimo

2016-10-01

The performance of long-haul high speed coherent optical fiber communication systems is significantly degraded by the laser phase noise and the equalization enhanced phase noise (EEPN). In this paper, the analysis of the one-tap normalized least-mean-square (LMS) carrier phase recovery (CPR) is carried out and the close-form expression is investigated for quadrature phase shift keying (QPSK) coherent optical fiber communication systems, in compensating both laser phase noise and equalization enhanced phase noise. Numerical simulations have also been implemented to verify the theoretical analysis. It is found that the one-tap normalized least-mean-square algorithm gives the same analytical expression for predicting CPR bit-error-rate (BER) floors as the traditional differential carrier phase recovery, when both the laser phase noise and the equalization enhanced phase noise are taken into account.

ISACS-DOC: Monitoring and Diagnostic System for AKARI and HINODE

NASA Astrophysics Data System (ADS)

Mizutani, Mitsue; Hirose, Toshinori; Takaki, Ryoji; Honda, Hideyuki

ISACS-DOC (Intelligent Satellite Control Software-DOCtor), which is an automatic monitoring and diagnostic system for scientific satellites or spacecraft, aims to rapidly and accurately capture important changes and sign of anomaly during daily satellite operations. After three systems for deep space missions, the new generation of ISACS-DOC with a higher speed processing performance had been developed for the satellites in earth orbit, AKARI and HINODE. This paper reports on the newest ISACS-DOC about enhanced functions, operating status, and an approach to create standards to build and keep up the knowledge data base. Continuous enhancements through the actual operations are the advantage of ISACS-DOC.

The ILLIAC IV memory system: Current status and future possibilities

NASA Technical Reports Server (NTRS)

Stevenson, D. K.

1978-01-01

The future needs of researchers who will use the Illiac were examined and the requirements they will place on the memory system were evaluated. Various alternatives to replacing critical memory components were considered with regard to cost, risk, system impact, software requirements, and implementation schedules. The current system, its performance and status, and the limitations it places on possible enhancements are discussed as well as the planned enhancements to the Illiac processor. After a brief technology survey, different implementations are presented for each system memory component. Three different memory systems are proposed to meet the identified needs of the Illiac user community. These three alternatives differ considerably with respect to storage capacity and accessing capabilities, but they all offer significant improvements over the current system. The proposed systems and their relative merits are analyzed.

Considerations in development of expert systems for real-time space applications

NASA Technical Reports Server (NTRS)

Murugesan, S.

1988-01-01

Over the years, demand on space systems has increased tremendously and this trend will continue for the near future. Enhanced capabilities of space systems, however, can only be met with increased complexity and sophistication of onboard and ground systems. Artificial Intelligence and expert system techniques have great potential in space applications. Expert systems could facilitate autonomous decision making, improve in-orbit fault diagnosis and repair, enhance performance and reduce reliance on ground support. However, real-time expert systems, unlike conventional off-line consultative systems, have to satisfy certain special stringent requirements before they could be used for onboard space applications. Challenging and interesting new environments are faced while developing expert system space applications. This paper discusses the special characteristics, requirements and typical life cycle issues for onboard expert systems. Further, it also describes considerations in design, development, and implementation which are particularly important to real-time expert systems for space applications.

Demonstration of an Enhanced Vertical Magnetic Gradient System for UXO

DTIC Science & Technology

2008-12-01

fluxgate magnetometers , data recording console, laser altimeter, and acoustic altimeters were tested to ensure proper operation and performance. The VG...Simultaneous Electromagnetic Induction and Magnetometer System WAA wide area assessment ACKNOWLEDGEMENTS We wish to express our sincere...sensors. The benefits of vertical gradient (VG) configurations in magnetometer systems are common knowledge, and these configurations are routinely

Development of a Diagnostic and Remedial Learning System Based on an Enhanced Concept--Effect Model

ERIC Educational Resources Information Center

Panjaburees, Patcharin; Triampo, Wannapong; Hwang, Gwo-Jen; Chuedoung, Meechoke; Triampo, Darapond

2013-01-01

With the rapid advances in computer technology during recent years, researchers have demonstrated the pivotal influences of computer-assisted diagnostic systems on student learning performance improvement. This research aims to develop a Diagnostic and Remedial Learning System (DRLS) for an algebra course in a Thai lower secondary school context…

Using computer graphics to enhance astronaut and systems safety

NASA Technical Reports Server (NTRS)

Brown, J. W.

1985-01-01

Computer graphics is being employed at the NASA Johnson Space Center as a tool to perform rapid, efficient and economical analyses for man-machine integration, flight operations development and systems engineering. The Operator Station Design System (OSDS), a computer-based facility featuring a highly flexible and versatile interactive software package, PLAID, is described. This unique evaluation tool, with its expanding data base of Space Shuttle elements, various payloads, experiments, crew equipment and man models, supports a multitude of technical evaluations, including spacecraft and workstation layout, definition of astronaut visual access, flight techniques development, cargo integration and crew training. As OSDS is being applied to the Space Shuttle, Orbiter payloads (including the European Space Agency's Spacelab) and future space vehicles and stations, astronaut and systems safety are being enhanced. Typical OSDS examples are presented. By performing physical and operational evaluations during early conceptual phases. supporting systems verification for flight readiness, and applying its capabilities to real-time mission support, the OSDS provides the wherewithal to satisfy a growing need of the current and future space programs for efficient, economical analyses.

β-Cyclodextrin associated polymeric systems: Rheology, flow behavior in porous media and enhanced heavy oil recovery performance.

PubMed

Wei, Bing

2015-12-10

This proof of concept research evaluates an approach to improve the enhanced heavy oil recovery performance of conventional polymers. Three associated polymeric systems, based on hydrolyzed polyacrylamide, xanthan gum, and a novel hydrophobic copolymer, were proposed in this work. The results of the theoretically rheology study indicate that these systems offer superior viscoelasticity and pronounced shear-thinning behavior due to the "interlocking effect". As a result of the surfactant collaboration, the dynamic interfacial tension between oil and polymer solution can be reduced by two orders of magnitude. Sandpack flooding tests demonstrated the capacity of the developed systems in mobility control during propagating in porous media, and the adsorption behavior was represented by the thickness of the adsorbed layer. The relationship between microscopic efficiency and capillary number indicated that the associated systems can significantly reduce the residual oil saturation due to the synergistic effect of the mobility reduction and surface activity, and the overall recovery efficiency was raised by 2-20% OOIP compared to the baseline polymers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Integrated, automated revenue management for managed care contracts.

PubMed

Burckhart, Kent

2002-04-01

Faced with increasing managed care penetration and declining net revenue in recent years, healthcare providers increasingly are emphasizing revenue management. To streamline processes and reduce costs in this area, many healthcare providers have implemented or are considering automated contract management systems. When selecting such a system, healthcare financial managers should make certain that the system can interface with both patient-accounting and decision-support systems of the organization. This integration enhances a healthcare provider's financial viability by providing integrated revenue-management capabilities to analyze projected performance of proposed managed care contracts and actual performance of existing contracts.

An expert system that performs a satellite station keepimg maneuver

NASA Technical Reports Server (NTRS)

Linesbrowning, M. Kate; Stone, John L., Jr.

1987-01-01

The development and characteristics of a prototype expert system, Expert System for Satellite Orbit Control (ESSOC), capable of providing real-time spacecraft system analysis and command generation for a geostationary satellite are described. The ESSOC recommends appropriate commands that reflect both the changing spacecraft condition and previous procedural action. An internal knowledge base stores satellite status information and is updated with processed spacecraft telemetry. Procedural structure data are encoded in production rules. Structural methods of knowledge acquisition and the design and performance-enhancing techniques that enable ESSOC to operate in real time are also considered.

System Construction of the Stilbene Compact Neutron Scatter Camera

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

Goldsmith, John E. M.; Gerling, Mark D.; Brennan, James S.

This report documents the construction of a stilbene-crystal-based compact neutron scatter camera. This system is essentially identical to the MINER (Mobile Imager of Neutrons for Emergency Responders) system previously built and deployed under DNN R&D funding,1 but with the liquid scintillator in the detection cells replaced by stilbene crystals. The availability of these two systems for side-by-side performance comparisons will enable us to unambiguously identify the performance enhancements provided by the stilbene crystals, which have only recently become commercially available in the large size required (3” diameter, 3” deep).

Oxidation catalyst

DOEpatents

Ceyer, Sylvia T.; Lahr, David L.

2010-11-09

The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

An Augmented-Reality Edge Enhancement Application for Google Glass

PubMed Central

Hwang, Alex D.; Peli, Eli

2014-01-01

Purpose Google Glass provides a platform that can be easily extended to include a vision enhancement tool. We have implemented an augmented vision system on Glass, which overlays enhanced edge information over the wearer’s real world view, to provide contrast-improved central vision to the Glass wearers. The enhanced central vision can be naturally integrated with scanning. Methods Goggle Glass’s camera lens distortions were corrected by using an image warping. Since the camera and virtual display are horizontally separated by 16mm, and the camera aiming and virtual display projection angle are off by 10°, the warped camera image had to go through a series of 3D transformations to minimize parallax errors before the final projection to the Glass’ see-through virtual display. All image processes were implemented to achieve near real-time performance. The impacts of the contrast enhancements were measured for three normal vision subjects, with and without a diffuser film to simulate vision loss. Results For all three subjects, significantly improved contrast sensitivity was achieved when the subjects used the edge enhancements with a diffuser film. The performance boost is limited by the Glass camera’s performance. The authors assume this accounts for why performance improvements were observed only with the diffuser filter condition (simulating low vision). Conclusions Improvements were measured with simulated visual impairments. With the benefit of see-through augmented reality edge enhancement, natural visual scanning process is possible, and suggests that the device may provide better visual function in a cosmetically and ergonomically attractive format for patients with macular degeneration. PMID:24978871

A generalized time-frequency subtraction method for robust speech enhancement based on wavelet filter banks modeling of human auditory system.

PubMed

Shao, Yu; Chang, Chip-Hong

2007-08-01

We present a new speech enhancement scheme for a single-microphone system to meet the demand for quality noise reduction algorithms capable of operating at a very low signal-to-noise ratio. A psychoacoustic model is incorporated into the generalized perceptual wavelet denoising method to reduce the residual noise and improve the intelligibility of speech. The proposed method is a generalized time-frequency subtraction algorithm, which advantageously exploits the wavelet multirate signal representation to preserve the critical transient information. Simultaneous masking and temporal masking of the human auditory system are modeled by the perceptual wavelet packet transform via the frequency and temporal localization of speech components. The wavelet coefficients are used to calculate the Bark spreading energy and temporal spreading energy, from which a time-frequency masking threshold is deduced to adaptively adjust the subtraction parameters of the proposed method. An unvoiced speech enhancement algorithm is also integrated into the system to improve the intelligibility of speech. Through rigorous objective and subjective evaluations, it is shown that the proposed speech enhancement system is capable of reducing noise with little speech degradation in adverse noise environments and the overall performance is superior to several competitive methods.

Man-Machine Interaction Design and Analysis System (MIDAS): Memory Representation and Procedural Implications for Airborne Communication Modalities

NASA Technical Reports Server (NTRS)

Corker, Kevin M.; Pisanich, Gregory M.; Lebacqz, Victor (Technical Monitor)

1996-01-01

The Man-Machine Interaction Design and Analysis System (MIDAS) has been under development for the past ten years through a joint US Army and NASA cooperative agreement. MIDAS represents multiple human operators and selected perceptual, cognitive, and physical functions of those operators as they interact with simulated systems. MIDAS has been used as an integrated predictive framework for the investigation of human/machine systems, particularly in situations with high demands on the operators. Specific examples include: nuclear power plant crew simulation, military helicopter flight crew response, and police force emergency dispatch. In recent applications to airborne systems development, MIDAS has demonstrated an ability to predict flight crew decision-making and procedural behavior when interacting with automated flight management systems and Air Traffic Control. In this paper we describe two enhancements to MIDAS. The first involves the addition of working memory in the form of an articulatory buffer for verbal communication protocols and a visuo-spatial buffer for communications via digital datalink. The second enhancement is a representation of multiple operators working as a team. This enhanced model was used to predict the performance of human flight crews and their level of compliance with commercial aviation communication procedures. We show how the data produced by MIDAS compares with flight crew performance data from full mission simulations. Finally, we discuss the use of these features to study communications issues connected with aircraft-based separation assurance.

Evaluation of a stereoscopic camera-based three-dimensional viewing workstation for ophthalmic surgery.

PubMed

Bhadri, Prashant R; Rowley, Adrian P; Khurana, Rahul N; Deboer, Charles M; Kerns, Ralph M; Chong, Lawrence P; Humayun, Mark S

2007-05-01

To evaluate the effectiveness of a prototype stereoscopic camera-based viewing system (Digital Microsurgical Workstation, three-dimensional (3D) Vision Systems, Irvine, California, USA) for anterior and posterior segment ophthalmic surgery. Institutional-based prospective study. Anterior and posterior segment surgeons performed designated standardized tasks on porcine eyes after training on prosthetic plastic eyes. Both anterior and posterior segment surgeons were able to complete tasks requiring minimal or moderate stereoscopic viewing. The results indicate that the system provides improved ergonomics. Improvements in key viewing performance areas would further enhance the value over a conventional operating microscope. The performance of the prototype system is not at par with the planned commercial system. With continued development of this technology, the three- dimensional system may be a novel viewing system in ophthalmic surgery with improved ergonomics with respect to traditional microscopic viewing.

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

Chevallier, J.J.; Quetier, F.P.; Marshall, D.W.

Sedco Forex has developed an integrated computer system to enhance the technical performance of the company at various operational levels and to increase the understanding and knowledge of the drill crews. This paper describes the system and how it is used for recording and processing drilling data at the rig site, for associated technical analyses, and for well design, planning, and drilling performance studies at the operational centers. Some capabilities related to the statistical analysis of the company's operational records are also described, and future development of rig computing systems for drilling applications and management tasks is discussed.

Phased array performance evaluation with photoelastic visualization

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

Ginzel, Robert; Dao, Gavin

2014-02-18

New instrumentation and a widening range of phased array transducer options are affording the industry a greater potential. Visualization of the complex wave components using the photoelastic system can greatly enhance understanding of the generated signals. Diffraction, mode conversion and wave front interaction, together with beam forming for linear, sectorial and matrix arrays, will be viewed using the photoelastic system. Beam focus and steering performance will be shown with a range of embedded and surface targets within glass samples. This paper will present principles and sound field images using this visualization system.

Portable wireless neurofeedback system of EEG alpha rhythm enhances memory.

PubMed

Wei, Ting-Ying; Chang, Da-Wei; Liu, You-De; Liu, Chen-Wei; Young, Chung-Ping; Liang, Sheng-Fu; Shaw, Fu-Zen

2017-11-13

Effect of neurofeedback training (NFT) on enhancement of cognitive function or amelioration of clinical symptoms is inconclusive. The trainability of brain rhythm using a neurofeedback system is uncertainty because various experimental designs are used in previous studies. The current study aimed to develop a portable wireless NFT system for alpha rhythm and to validate effect of the NFT system on memory with a sham-controlled group. The proposed system contained an EEG signal analysis device and a smartphone with wireless Bluetooth low-energy technology. Instantaneous 1-s EEG power and contiguous 5-min EEG power throughout the training were developed as feedback information. The training performance and its progression were kept to boost usability of our device. Participants were blinded and randomly assigned into either the control group receiving random 4-Hz power or Alpha group receiving 8-12-Hz power. Working memory and episodic memory were assessed by the backward digital span task and word-pair task, respectively. The portable neurofeedback system had advantages of a tiny size and long-term recording and demonstrated trainability of alpha rhythm in terms of significant increase of power and duration of 8-12 Hz. Moreover, accuracies of the backward digital span task and word-pair task showed significant enhancement in the Alpha group after training compared to the control group. Our tiny portable device demonstrated success trainability of alpha rhythm and enhanced two kinds of memories. The present study suggest that the portable neurofeedback system provides an alternative intervention for memory enhancement.

Analysis of a front suspension system for UniART FSAE car using FEA

NASA Astrophysics Data System (ADS)

Zaidie, M. N. A.; Hashim, M. S. M.; Tasyrif, M.; Basha, M. H.; Ibrahim, I.; Kamaruddin, N. S.; Shahriman, A. B.

2017-10-01

In recent years, many research works from institutions that participated in Formula SAE had highlighted on suspension systems. The aim is to improve the system in term of performance and robustness. However, every suspension system for a racing car is tailored to the car itself. Thus, this paper proposes a new design for front suspension system for UniART FSAE car. The new design was than being compared to the previous suspension system for enhancement. The analysis covered in this paper based on several conditions such as braking, cornering and bumping condition and was carried out using finite element analysis. Each main component for the suspension system such as lower arm, upper arm and knuckle has been analysed in term of strength and performance. From the results, the proposed new design of the suspension system has improved in term of strength and performance compared to the previous suspension system.

Recent Science and Engineering Results with the Laser Guidestar Adaptive Optics System at Lick Observatory

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

Gavel, D T; Gates, E; Max, C

2002-10-17

The Lick Observatory laser guide star adaptive optics system has undergone continual improvement and testing as it is being integrated as a facility science instrument on the Shane 3 meter telescope. Both Natural Guide Star (NGS) and Laser Guide Star (LGS) modes are now used in science observing programs. We report on system performance results as derived from data taken on both science and engineering nights and also describe the newly developed on-line techniques for seeing and system performance characterization. We also describe the future enhancements to the Lick system that will enable additional science goals such as long-exposure spectroscopy.

Enhancing the Design Process for Complex Space Systems through Early Integration of Risk and Variable-Fidelity Modeling

NASA Technical Reports Server (NTRS)

Mavris, Dimitri; Osburg, Jan

2005-01-01

An important enabler of the new national Vision for Space Exploration is the ability to rapidly and efficiently develop optimized concepts for the manifold future space missions that this effort calls for. The design of such complex systems requires a tight integration of all the engineering disciplines involved, in an environment that fosters interaction and collaboration. The research performed under this grant explored areas where the space systems design process can be enhanced: by integrating risk models into the early stages of the design process, and by including rapid-turnaround variable-fidelity tools for key disciplines. Enabling early assessment of mission risk will allow designers to perform trades between risk and design performance during the initial design space exploration. Entry into planetary atmospheres will require an increased emphasis of the critical disciplines of aero- and thermodynamics. This necessitates the pulling forward of EDL disciplinary expertise into the early stage of the design process. Radiation can have a large potential impact on overall mission designs, in particular for the planned nuclear-powered robotic missions under Project Prometheus and for long-duration manned missions to the Moon, Mars and beyond under Project Constellation. This requires that radiation and associated risk and hazards be assessed and mitigated at the earliest stages of the design process. Hence, RPS is another discipline needed to enhance the engineering competencies of conceptual design teams. Researchers collaborated closely with NASA experts in those disciplines, and in overall space systems design, at Langley Research Center and at the Jet Propulsion Laboratory. This report documents the results of this initial effort.

Using Electronic Assessment Systems to Enhance Instruction

ERIC Educational Resources Information Center

Domagala, Jospeh F.

2017-01-01

Teachers in the classroom need to be able to modify instruction in a meaningful way that helps students to improve academically. School districts provide electronic assessment data which helps teachers identify areas for improvement within their instruction. Electronic performance assessment systems can be an effective means of assisting schools…

FUZZY LOGIC BASED INTELLIGENT CONTROL OF A VARIABLE SPEED CAGE MACHINE WIND GENERATION SYSTEM

EPA Science Inventory

The report gives results of a demonstration of the successful application of fuzzy logic to enhance the performance and control of a variable-speed wind generation system. A squirrel cage induction generator feeds the power to either a double-sided pulse-width modulation converte...

System Models and Aging: A Driving Example.

ERIC Educational Resources Information Center

Melichar, Joseph F.

Chronological age is a marker in time but it fails to measure accurately the performance or behavioral characteristics of individuals. This paper models the complexity of aging by using a system model and a human function paradigm. These models help facilitate representation of older adults, integrate research agendas, and enhance remediative…

Complex Teacher Evaluation Systems Can Produce Negative Perceptions

ERIC Educational Resources Information Center

Schumacher, Gary

2010-01-01

The purpose of this study was to determine teacher perceptions of the impact on instructional practice when using a complex, standards-based performance evaluation system. The study used expectancy theory to investigate teacher expectancy (did they believe they could enhance their practice to the identified program standards?), instrumentality…

Visual Systems for Teleconferencing: Telewriting, Televideo, and Facsimile.

ERIC Educational Resources Information Center

Olgren, Christine

Telewriting, televideo, and facsimile systems are new forms of teleconferencing which can transmit a variety of graphic and pictorial information on voice-grade telephone lines. All of the equipment employs solid-state circuitry to enhance performance and to exploit the limitations of a narrowband channel. Telewriters range from simple…

Enhancing the Internet of Things Architecture with Flow Semantics

ERIC Educational Resources Information Center

DeSerranno, Allen Ronald

2017-01-01

Internet of Things ("IoT") systems are complex, asynchronous solutions often comprised of various software and hardware components developed in isolation of each other. These components function with different degrees of reliability and performance over an inherently unreliable network, the Internet. Many IoT systems are developed within…

Smart Homes and Buildings Research at the Energy Systems Integration Facility

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

Christensen, Dane; Sparn, Bethany; Hannegan, Bryan

Watch how NREL researchers are using the unique capabilities of the Energy Systems Integration Facility (ESIF) to develop technologies that will help the “smart” homes and buildings of the future perform efficiently and communicate effectively with the electricity grid while enhancing occupants' comfort and convenience.

The Influence of Cultural Factors on Trust in Automation

ERIC Educational Resources Information Center

Chien, Shih-Yi James

2016-01-01

Human interaction with automation is a complex process that requires both skilled operators and complex system designs to effectively enhance overall performance. Although automation has successfully managed complex systems throughout the world for over half a century, inappropriate reliance on automation can still occur, such as the recent…

Development of nanostructured antireflection coatings for infrared technologies and applications

NASA Astrophysics Data System (ADS)

Pethuraja, Gopal G.; Zeller, John W.; Welser, Roger E.; Efstathiadis, Harry; Haldar, Pradeep; Wijewarnasuriya, Priyalal S.; Dhar, Nibir K.; Sood, Ashok K.

2017-09-01

Infrared (IR) sensing technologies and systems operating from the near-infrared (NIR) to long-wave infrared (LWIR) spectra are being developed for a variety of defense and commercial systems applications. Reflection losses affecting a significant portion of the incident signal limits the performance of IR sensing systems. One of the critical technologies that will overcome this limitation and enhance the performance of IR sensing systems is the development of advanced antireflection (AR) coatings. Magnolia is actively involved in the development and advancement of ultrahigh performance AR coatings for a wide variety of defense and commercial applications. Ultrahigh performance nanostructured AR coatings have been demonstrated for UV to LWIR spectral bands using various substrates. The AR coatings enhance the optical transmission through optical components and devices by significantly minimizing reflection losses, a substantial improvement over conventional thin-film AR coating technologies. Nanostructured AR coatings are fabricated using a tunable self-assembly process on substrates that are transparent for a given spectrum of interest ranging from UV to LWIR. The nanostructured multilayer structures have been designed, developed and optimized for various optoelectronic applications. The optical properties of the AR-coated optical components and sensor substrates have been measured and fine-tuned to achieve a predicted high level of performance of the coatings. In this paper, we review our latest work on high quality nanostructure-based AR coatings, including recent efforts towards the development of nanostructured AR coatings on IR-transparent substrates.

Development of a HIV-1 Virus Detection System Based on Nanotechnology.

PubMed

Lee, Jin-Ho; Oh, Byung-Keun; Choi, Jeong-Woo

2015-04-27

Development of a sensitive and selective detection system for pathogenic viral agents is essential for medical healthcare from diagnostics to therapeutics. However, conventional detection systems are time consuming, resource-intensive and tedious to perform. Hence, the demand for sensitive and selective detection system for virus are highly increasing. To attain this aim, different aspects and techniques have been applied to develop virus sensor with improved sensitivity and selectivity. Here, among those aspects and techniques, this article reviews HIV virus particle detection systems incorporated with nanotechnology to enhance the sensitivity. This review mainly focused on four different detection system including vertically configured electrical detection based on scanning tunneling microscopy (STM), electrochemical detection based on direct electron transfer in virus, optical detection system based on localized surface plasmon resonance (LSPR) and surface enhanced Raman spectroscopy (SERS) using plasmonic nanoparticle.

Effects of Noise-Induced Coherence on the Performance of Quantum Absorption Refrigerators

NASA Astrophysics Data System (ADS)

Holubec, Viktor; Novotný, Tomáš

2018-05-01

We study two models of quantum absorption refrigerators with the main focus on discerning the role of noise-induced coherence on their thermodynamic performance. Analogously to the previous studies on quantum heat engines, we find the increase in the cooling power due to the mechanism of noise-induced coherence. We formulate conditions imposed on the microscopic parameters of the models under which they can be equivalently described by classical stochastic processes and compare the performance of the two classes of fridges (effectively classical vs. truly quantum). We find that the enhanced performance is observed already for the effectively classical systems, with no significant qualitative change in the quantum cases, which suggests that the noise-induced-coherence-enhancement mechanism is caused by static interference phenomena.

Electric-field enhanced performance in catalysis and solid-state devices involving gases

DOEpatents

Blackburn, Bryan M.; Wachsman, Eric D.; Van Assche, IV, Frederick Martin

2015-05-19

Electrode configurations for electric-field enhanced performance in catalysis and solid-state devices involving gases are provided. According to an embodiment, electric-field electrodes can be incorporated in devices such as gas sensors and fuel cells to shape an electric field provided with respect to sensing electrodes for the gas sensors and surfaces of the fuel cells. The shaped electric fields can alter surface dynamics, system thermodynamics, reaction kinetics, and adsorption/desorption processes. In one embodiment, ring-shaped electric-field electrodes can be provided around sensing electrodes of a planar gas sensor.

Metrics for the National SCADA Test Bed Program

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

Craig, Philip A.; Mortensen, J.; Dagle, Jeffery E.

2008-12-05

The U.S. Department of Energy Office of Electricity Delivery and Energy Reliability (DOE-OE) National SCADA Test Bed (NSTB) Program is providing valuable inputs into the electric industry by performing topical research and development (R&D) to secure next generation and legacy control systems. In addition, the program conducts vulnerability and risk analysis, develops tools, and performs industry liaison, outreach and awareness activities. These activities will enhance the secure and reliable delivery of energy for the United States. This report will describe metrics that could be utilized to provide feedback to help enhance the effectiveness of the NSTB Program.

Study on the application of NASA energy management techniques for control of a terrestrial solar water heating system

NASA Technical Reports Server (NTRS)

Swanson, T. D.; Ollendorf, S.

1979-01-01

This paper addresses the potential for enhanced solar system performance through sophisticated control of the collector loop flow rate. Computer simulations utilizing the TRNSYS solar energy program were performed to study the relative effect on system performance of eight specific control algorithms. Six of these control algorithms are of the proportional type: two are concave exponentials, two are simple linear functions, and two are convex exponentials. These six functions are typical of what might be expected from future, more advanced, controllers. The other two algorithms are of the on/off type and are thus typical of existing control devices. Results of extensive computer simulations utilizing actual weather data indicate that proportional control does not significantly improve system performance. However, it is shown that thermal stratification in the liquid storage tank may significantly improve performance.

EROS Data Center Landsat digital enhancement techniques and imagery availability

USGS Publications Warehouse

Rohde, Wayne G.; Lo, Jinn Kai; Pohl, Russell A.

1978-01-01

The US Geological Survey's EROS Data Center (EDC) is experimenting with the production of digitally enhanced Landsat imagery. Advanced digital image processing techniques are used to perform geometric and radiometric corrections and to perform contrast and edge enhancements. The enhanced image product is produced from digitally preprocessed Landsat computer compatible tapes (CCTs) on a laser beam film recording system. Landsat CCT data have several geometric distortions which are corrected when NASA produces the standard film products. When producing film images from CCT's, geometric correction of the data is required. The EDC Digital Image Enhancement System (EDIES) compensates for geometric distortions introduced by Earth's rotation, variable line length, non-uniform mirror scan velocity, and detector misregistration. Radiometric anomalies such as bad data lines and striping are common to many Landsat film products and are also in the CCT data. Bad data lines or line segments with more than 150 contiguous bad pixels are corrected by inserting data from the previous line in place of the bad data. Striping, caused by variations in detector gain and offset, is removed with a destriping algorithm applied after digitally enhancing the data. Image enhancement is performed by applying a linear contrast stretch and an edge enhancement algorithm. The linear contrast enhancement algorithm is designed to expand digitally the full range of useful data recorded on the CCT over the range of 256 digital counts. This minimizes the effect of atmospheric scattering and saturates the relative brightness of highly reflecting features such as clouds or snow. It is the intent that no meaningful terrain data are eliminated by the digital processing. The edge enhancement algorithm is designed to enhance boundaries between terrain features that exhibit subtle differences in brightness values along edges of features. After the digital data have been processed, data for each Landsat band are recorded on black-and-white film with a laser beam film recorder (LBR). The LBR corrects for aspect ratio distortions as the digital data are recorded on the recording film over a preselected density range. Positive transparencies of MSS bands 4, 5, and 7 produced by the LBR are used to make color composite transparencies. Color film positives are made photographically from first generation black-and-white products generated on the LBR.

Visualizing feasible operating ranges within tissue engineering systems using a "windows of operation" approach: a perfusion-scaffold bioreactor case study.

PubMed

McCoy, Ryan J; O'Brien, Fergal J

2012-12-01

Tissue engineering approaches to developing functional substitutes are often highly complex, multivariate systems where many aspects of the biomaterials, bio-regulatory factors or cell sources may be controlled in an effort to enhance tissue formation. Furthermore, success is based on multiple performance criteria reflecting both the quantity and quality of the tissue produced. Managing the trade-offs between different performance criteria is a challenge. A "windows of operation" tool that graphically represents feasible operating spaces to achieve user-defined levels of performance has previously been described by researchers in the bio-processing industry. This paper demonstrates the value of "windows of operation" to the tissue engineering field using a perfusion-scaffold bioreactor system as a case study. In our laboratory, perfusion bioreactor systems are utilized in the context of bone tissue engineering to enhance the osteogenic differentiation of cell-seeded scaffolds. A key challenge of such perfusion bioreactor systems is to maximize the induction of osteogenesis but minimize cell detachment from the scaffold. Two key operating variables that influence these performance criteria are the mean scaffold pore size and flow-rate. Using cyclooxygenase-2 and osteopontin gene expression levels as surrogate indicators of osteogenesis, we employed the "windows of operation" methodology to rapidly identify feasible operating ranges for the mean scaffold pore size and flow-rate that achieved user-defined levels of performance for cell detachment and differentiation. Incorporation of such tools into the tissue engineer's armory will hopefully yield a greater understanding of the highly complex systems used and help aid decision making in future translation of products from the bench top to the market place. Copyright © 2012 Wiley Periodicals, Inc.

Penetration enhancer-containing vesicles (PEVs) as carriers for cutaneous delivery of minoxidil: in vitro evaluation of drug permeation by infrared spectroscopy.

PubMed

Mura, Simona; Manconi, Maria; Fadda, Anna Maria; Sala, Maria Chiara; Perricci, Jacopo; Pini, Elena; Sinico, Chiara

2013-01-01

Recently, we carried out a research on new liposomal systems prepared by using in their composition a few penetration enhancers which differ for chemical structure and physicochemical properties. The penetration enhancer-containing vesicles (PEVs) were prepared by using soy lecithin and different amounts of three penetration enhancers, 2-(2-ethoxyethoxy) ethanol (Transcutol(®)), capryl-caproyl macrogol 8-glyceride (Labrasol(®)), and cineole.To study the influence of the PEVs on (trans)dermal delivery of minoxidil, in vitro diffusion experiments were performed through new born pig skin and the results were compared with that obtained applying the vesicular system without enhancer (control) after pretreatment of the skin with the various enhancers. In this study, Fourier transform infrared spectroscopy (FTIR), attenuated total reflectance FTIR (ATR-FTIR) and FTIR imaging were used to evaluate the effective penetration of minoxidil in the skin layers and to discover the influence of the enhancer on the drug topical delivery. These analytical studies allowed us to characterize the drug formulations and to evaluate the vesicle distribution into the skin. Recorded spectra confirmed that the vesicle formulations with penetration enhancers promoted drug deposition into the skin.

Biometrics in Government, Post-9/11: Advancing Science, Enhancing Operations

DTIC Science & Technology

2008-08-01

responsibilities include advising the President in policy formulation and budget development on all questions in which S&T are important elements; articulating the...group of approximately 30 individuals from government, industry, and academia were in a hotel conference room in Orlando, Fla., at a Biometric...of a set of usability guidelines for biometric systems that enhance performance (throughput and quality), improve user satisfaction and acceptance

Enhanced Raman scattering in porous silicon grating.

PubMed

Wang, Jiajia; Jia, Zhenhong; Lv, Changwu

2018-03-19

The enhancement of Raman signal on monocrystalline silicon gratings with varying groove depths and on porous silicon grating were studied for a highly sensitive surface enhanced Raman scattering (SERS) response. In the experiment conducted, porous silicon gratings were fabricated. Silver nanoparticles (Ag NPs) were then deposited on the porous silicon grating to enhance the Raman signal of the detective objects. Results show that the enhancement of Raman signal on silicon grating improved when groove depth increased. The enhanced performance of Raman signal on porous silicon grating was also further improved. The Rhodamine SERS response based on Ag NPs/ porous silicon grating substrates was enhanced relative to the SERS response on Ag NPs/ porous silicon substrates. Ag NPs / porous silicon grating SERS substrate system achieved a highly sensitive SERS response due to the coupling of various Raman enhancement factors.

Development and Validation of Performance Assessment Tools for Interprofessional Communication and Teamwork (PACT)

ERIC Educational Resources Information Center

Chiu, Chia-Ju

2014-01-01

Background: Medical errors caused by breakdowns in teamwork and interprofessional communication contribute to many deaths in the United States each year. Team Strategies and Tools to Enhance Performance and Patient Safety (TeamSTEPPS®) is an evidence-based teamwork system developed to improve communication and teamwork skills among health care…

Tracking and Data Relay Satellite System (TDRSS) navigation with DSN radio metric data

NASA Technical Reports Server (NTRS)

Ellis, J.

1981-01-01

The use of DSN radiometric data for enhancing the orbit determination capability for TDRS is examined. Results of a formal covariance analysis are presented which establish the nominal TDRS navigation performance and assess the performance improvement based on augmenting the nominal TDRS data strategy with radiometric data from DSN sites.

Compact Deep-Space Optical Communications Transceiver

NASA Technical Reports Server (NTRS)

Roberts, W. Thomas; Charles, Jeffrey R.

2009-01-01

Deep space optical communication transceivers must be very efficient receivers and transmitters of optical communication signals. For deep space missions, communication systems require high performance well beyond the scope of mere power efficiency, demanding maximum performance in relation to the precious and limited mass, volume, and power allocated. This paper describes the opto-mechanical design of a compact, efficient, functional brassboard deep space transceiver that is capable of achieving megabyte-per-second rates at Mars ranges. The special features embodied to enhance the system operability and functionality, and to reduce the mass and volume of the system are detailed. System tests and performance characteristics are described in detail. Finally, lessons learned in the implementation of the brassboard design and suggestions for improvements appropriate for a flight prototype are covered.

Internal Flow Simulation of Enhanced Performance Solid Rocket Booster for the Space Transportation System

NASA Technical Reports Server (NTRS)

Ahmad, Rashid A.; McCool, Alex (Technical Monitor)

2001-01-01

An enhanced performance solid rocket booster concept for the space shuttle system has been proposed. The concept booster will have strong commonality with the existing, proven, reliable four-segment Space Shuttle Reusable Solid Rocket Motors (RSRM) with individual component design (nozzle, insulator, etc.) optimized for a five-segment configuration. Increased performance is desirable to further enhance safety/reliability and/or increase payload capability. Performance increase will be achieved by adding a fifth propellant segment to the current four-segment booster and opening the throat to accommodate the increased mass flow while maintaining current pressure levels. One development concept under consideration is the static test of a "standard" RSRM with a fifth propellant segment inserted and appropriate minimum motor modifications. Feasibility studies are being conducted to assess the potential for any significant departure in component performance/loading from the well-characterized RSRM. An area of concern is the aft motor (submerged nozzle inlet, aft dome, etc.) where the altered internal flow resulting from the performance enhancing features (25% increase in mass flow rate, higher Mach numbers, modified subsonic nozzle contour) may result in increased component erosion and char. To assess this issue and to define the minimum design changes required to successfully static test a fifth segment RSRM engineering test motor, internal flow studies have been initiated. Internal aero-thermal environments were quantified in terms of conventional convective heating and discrete phase alumina particle impact/concentration and accretion calculations via Computational Fluid Dynamics (CFD) simulation. Two sets of comparative CFD simulations of the RSRM and the five-segment (IBM) concept motor were conducted with CFD commercial code FLUENT. The first simulation involved a two-dimensional axi-symmetric model of the full motor, initial grain RSRM. The second set of analyses included three-dimensional models of the RSRM and FSM aft motors with four-degree vectored nozzles.

Fusion solution for soldier wearable gunfire detection systems

NASA Astrophysics Data System (ADS)

Cakiades, George; Desai, Sachi; Deligeorges, Socrates; Buckland, Bruce E.; George, Jemin

2012-06-01

Currently existing acoustic based Gunfire Detection Systems (GDS) such as soldier wearable, vehicle mounted, and fixed site devices provide enemy detection and localization capabilities to the user. However, the solution to the problem of portability versus performance tradeoff remains elusive. The Data Fusion Module (DFM), described herein, is a sensor/platform agnostic software supplemental tool that addresses this tradeoff problem by leveraging existing soldier networks to enhance GDS performance across a Tactical Combat Unit (TCU). The DFM software enhances performance by leveraging all available acoustic GDS information across the TCU synergistically to calculate highly accurate solutions more consistently than any individual GDS in the TCU. The networked sensor architecture provides additional capabilities addressing the multiple shooter/fire-fight problems in addition to sniper detection/localization. The addition of the fusion solution to the overall Size, Weight and Power & Cost (SWaP&C) is zero to negligible. At the end of the first-year effort, the DFM integrated sensor network's performance was impressive showing improvements upwards of 50% in comparison to a single sensor solution. Further improvements are expected when the networked sensor architecture created in this effort is fully exploited.

Benchmarks for Enhanced Network Performance: Hands-On Testing of Operating System Solutions to Identify the Optimal Application Server Platform for the Graduate School of Business and Public Policy

DTIC Science & Technology

2010-09-01

for Applied Mathematics. Kennedy, R. C. (2009a). Clocking Windows netbook performance. Retrieved on 08/14/2010, from http...podcasts.infoworld.com/d/hardware/clocking-windows- netbook -performance-883?_kip_ipx=1177119066-1281460794 Kennedy, R. C. (2009b). OfficeBench 7: A cool new way to

Review of Aircraft Engine Fan Noise Reduction

NASA Technical Reports Server (NTRS)

VanZante, Dale

2008-01-01

Aircraft turbofan engines incorporate multiple technologies to enhance performance and durability while reducing noise emissions. Both careful aerodynamic design of the fan and proper installation of the fan into the system are requirements for achieving the performance and acoustic objectives. The design and installation characteristics of high performance aircraft engine fans will be discussed along with some lessons learned that may be applicable to spaceflight fan applications.

Performance evaluation of the time delay digital tanlock loop architectures

NASA Astrophysics Data System (ADS)

Al-Kharji Al-Ali, Omar; Anani, Nader; Al-Qutayri, Mahmoud; Al-Araji, Saleh; Ponnapalli, Prasad

2016-01-01

This article presents the architectures, theoretical analyses and testing results of modified time delay digital tanlock loop (TDTLs) system. The modifications to the original TDTL architecture were introduced to overcome some of the limitations of the original TDTL and to enhance the overall performance of the particular systems. The limitations addressed in this article include the non-linearity of the phase detector, the restricted width of the locking range and the overall system acquisition speed. Each of the modified architectures was tested by subjecting the system to sudden positive and negative frequency steps and comparing its response with that of the original TDTL. In addition, the performance of all the architectures was evaluated under noise-free as well as noisy environments. The extensive simulation results using MATLAB/SIMULINK demonstrate that the new architectures overcome the limitations they addressed and the overall results confirmed significant improvements in performance compared to the conventional TDTL system.

Beyond feedback control: the interactive use of performance management systems. Implications for process innovation in Italian healthcare organizations.

PubMed

Demartini, Chiara; Mella, Piero

2014-01-01

This paper shows how the use of performance management systems affects managers' perception of satisfaction, the effectiveness of the control system and the performance related to process innovation. An exploratory empirical research has been conducted on 85 managers operating in Italian healthcare organizations. Empirical findings put forward that the interactive--as opposed to diagnostic--use of performance management systems enhances managerial satisfaction with the control system and managerial perception of effectiveness. The present study then showed that it is not the control itself that is an obstacle to innovation in organizations in general (and in health organizations in particular) but the diagnostic use of the control mechanisms, which impedes the interaction between the control personnel and those subject to the control. Finally, this paper addresses managerial implications and further research avenues. Copyright © 2013 John Wiley & Sons, Ltd.

Active imaging systems to perform the strategic surveillance of an aircraft environment in bad weather conditions

NASA Astrophysics Data System (ADS)

Riviere, Nicolas; Hespel, Laurent; Ceolato, Romain; Drouet, Florence

2011-11-01

Onera, the French Aerospace Lab, develops and models active imaging systems to understand the relevant physical phenomena impacting on their performances. As a consequence, efforts have been done both on the propagation of a pulse through the atmosphere (scintillation and turbulence effects) and, on target geometries and their surface properties (radiometric and speckle effects). But these imaging systems must operate at night in all ambient illuminations and weather conditions in order to perform the strategic surveillance of the environment for various worldwide operations or to perform the enhanced navigation of an aircraft. Onera has implemented codes for 2D and 3D laser imaging systems. As we aim to image a scene even in the presence of rain, snow, fog or haze, Onera introduces such meteorological effects in these numerical models and compares simulated images with measurements provided by commercial imaging systems.

Microwave remote plasma enhanced-atomic layer deposition system with multicusp confinement chamber

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

Dechana, A.; Thamboon, P.; Boonyawan, D., E-mail: dheerawan.b@cmu.ac.th

A microwave remote Plasma Enhanced-Atomic Layer Deposition system with multicusp confinement chamber is established at the Plasma and Beam Physics research facilities, Chiang Mai, Thailand. The system produces highly-reactive plasma species in order to enhance the deposition process of thin films. The addition of the multicusp magnetic fields further improves the plasma density and uniformity in the reaction chamber. Thus, the system is more favorable to temperature-sensitive substrates when heating becomes unwanted. Furthermore, the remote-plasma feature, which is generated via microwave power source, offers tunability of the plasma properties separately from the process. As a result, the system provides highmore » flexibility in choice of materials and design experiments, particularly for low-temperature applications. Performance evaluations of the system were carried on coating experiments of Al{sub 2}O{sub 3} layers onto a silicon wafer. The plasma characteristics in the chamber will be described. The resulted Al{sub 2}O{sub 3} films—analyzed by Rutherford Backscattering Spectrometry in channeling mode and by X-ray Photoelectron Spectroscopy techniques—will be discussed.« less

Improved removal performance and mechanism investigation of papermaking wastewater treatment using manganese enhanced Fenton reaction.

PubMed

Wang, Yingcai; Wang, Can; Shi, Shuai; Fang, Shuai

2018-06-01

The effects of Mn(II) on Fenton system to treat papermaking wastewater and the mechanism of Mn(II) enhanced Fenton reaction were investigated in this study. The chemical oxygen demand (COD) removal efficiency was enhanced in the presence of Mn(II), which increased by 19% compared with that of the Fenton system alone. The pseudo-first order reaction kinetic rate constant of Mn(II)/Fenton system was 2.11 times higher than that of Fenton system. 67%-81% COD were removed with the increasing Mn(II) concentration from 0 to 0.8 g/L. COD removal efficiency was also enhanced in a wider pH range (3-7), which indicated the operation parameters of Fenton technology could be broadened to a milder condition. The study of the mechanism showed that Mn(II) participated in the oxidation and coagulation stages in Fenton system. In the oxidation stage, Mn(II) promotes the production of HO 2 •/ O 2 • - , then HO 2 •/ O 2 • - reacts with Fe(III) to accelerate the formation of Fe(II), and finally accelerates the production of HO•. Meantime MnMnO 3 and Fe(OH) 3 forms in the coagulation stage, facilitating the removal of suspended substances and a large amount of COD, which enhances the overall COD removal of papermaking wastewater. This study provided a detailed mechanism to improve practical applications of Fenton technology.

Data management system advanced development

NASA Technical Reports Server (NTRS)

Douglas, Katherine; Humphries, Terry

1990-01-01

The Data Management System (DMS) Advanced Development task provides for the development of concepts, new tools, DMS services, and for the testing of the Space Station DMS hardware and software. It also provides for the development of techniques capable of determining the effects of system changes/enhancements, additions of new technology, and/or hardware and software growth on system performance. This paper will address the built-in characteristics which will support network monitoring requirements in the design of the evolving DMS network implementation, functional and performance requirements for a real-time, multiprogramming, multiprocessor operating system, and the possible use of advanced development techniques such as expert systems and artificial intelligence tools in the DMS design.

Hierarchical Ada robot programming system (HARPS)- A complete and working telerobot control system based on the NASREM model

NASA Technical Reports Server (NTRS)

Leake, Stephen; Green, Tom; Cofer, Sue; Sauerwein, Tim

1989-01-01

HARPS is a telerobot control system that can perform some simple but useful tasks. This capability is demonstrated by performing the ORU exchange demonstration. HARPS is based on NASREM (NASA Standard Reference Model). All software is developed in Ada, and the project incorporates a number of different CASE (computer-aided software engineering) tools. NASREM was found to be a valid and useful model for building a telerobot control system. Its hierarchical and distributed structure creates a natural and logical flow for implementing large complex robust control systems. The ability of Ada to create and enforce abstraction enhanced the implementation of such control systems.

Cavity Enhanced Spectrometer performance assessment for greenhouse gas dry mole fraction measurement in humid air.

NASA Astrophysics Data System (ADS)

Laurent, Olivier; Yver Kwok, Camille; Guemri, Ali; Philippon, Carole; Rivier, Leonard; Ramonet, Michel

2017-04-01

Due to the high variability of the water vapor content in the atmosphere, the mole fraction of trace gas such as greenhouse gas (GHG) in the atmosphere is usually presented as mole fraction in dry air. In consequence, the first technology used for GHG measurement, gas chromatography or non-dispersive infra-red spectroscopy, required to dry the air sample prior to analysis at a dew point lower than -50°C. The emergence of new GHG analyzers using infrared Enhanced Cavity Spectroscopy which measure the water vapor content in the air sample, allows providing the dry mole fraction of GHG without any drying system upstream by applying appropriate correction of the water vapor effects (dilution, pressure broadening…). In the framework of ICOS, a European research infrastructure aiming to provide harmonized high precision data for advanced research on carbon cycle and GHG budgets over Europe, the Metrology Lab of the Atmosphere Thematic Centre (ATC), located at LSCE in France, is mainly dedicated to elaborating measurement protocols and evaluating performance of GHG analyzers. Among the different tests conducted to characterize the metrological performance, the Metrology Lab focuses on the water vapor correction to apply on the GHG measurement. Most of the analyzers tested at the Metrology Lab are based on Cavity Enhanced Spectroscopy measuring the ICOS mandatory species, CO2, CH4 and CO. This presentation presents the results of the performance assessment of the manufacturer built-in water vapor correction and the possible improvement. Thanks to the large number of instrument tested, the presentation provides a performance overview of the GHG analyzers deployed in the ICOS atmospheric station network. Finally the performance of the water vapor correction will be discussed in regard of the performance obtained by using a drying system.

Combined Dynamic Time Warping with Multiple Sensors for 3D Gesture Recognition

PubMed Central

2017-01-01

Cyber-physical systems, which closely integrate physical systems and humans, can be applied to a wider range of applications through user movement analysis. In three-dimensional (3D) gesture recognition, multiple sensors are required to recognize various natural gestures. Several studies have been undertaken in the field of gesture recognition; however, gesture recognition was conducted based on data captured from various independent sensors, which rendered the capture and combination of real-time data complicated. In this study, a 3D gesture recognition method using combined information obtained from multiple sensors is proposed. The proposed method can robustly perform gesture recognition regardless of a user’s location and movement directions by providing viewpoint-weighted values and/or motion-weighted values. In the proposed method, the viewpoint-weighted dynamic time warping with multiple sensors has enhanced performance by preventing joint measurement errors and noise due to sensor measurement tolerance, which has resulted in the enhancement of recognition performance by comparing multiple joint sequences effectively. PMID:28817094

A simulation evaluation of the engine monitoring and control system display

NASA Technical Reports Server (NTRS)

Abbott, Terence S.

1990-01-01

The Engine Monitoring and Control System (E-MACS) display is a new concept for an engine instrument display, the purpose of which is to provide an enhanced means for a pilot to control and monitor aircraft engine performance. It provides graphically-presented information about performance capabilities, current performance, and engine component or subsystem operational conditions relative to nominal conditions. The concept was evaluated by sixteen pilot-subjects against a traditional, state-of-the-art electronic engine display format. The results of this evaluation showed a substantial pilot preference for the E-MACS display relative to the traditional display. The results of the failure detection portion of the evaluation showed a 100 percent detection rate for the E-MACS display relative to a 57 percent rate for the traditional display. From these results, it is concluded that by providing this type of information in the cockpit, a reduction in pilot workload and an enhanced ability for detecting degraded or off-nominal conditions is probable, thus leading to an increase in operational safety.

NASA Research Announcement Phase 1 Report and Phase 2 Proposal for the Development of a Power Assisted Space Suit Glove Assembly

NASA Technical Reports Server (NTRS)

Cadogan, Dave; Lingo, Bob

1996-01-01

In July of 1996, ILC Dover was awarded Phase 1 of a contract for NASA to develop a prototype Power Assisted Space Suit glove to enhance the performance of astronauts during Extra-Vehicular Activity (EVA). This report summarizes the work performed to date on Phase 1, and details the work to be conducted on Phase 2 of the program. Phase 1 of the program consisted of research and review of related technical sources, concept brainstorming, baseline design development, modeling and analysis, component mock-up testing, and test data analysis. ILC worked in conjunction with the University of Maryland's Space Systems Laboratory (SSL) to develop the power assisted glove. Phase 2 activities will focus on the design maturation and the manufacture of a working prototype system. The prototype will be tested and evaluated in conjunction with existing space suit glove technology to determine the performance enhancement anticipated with the implementation of the power assisted joint technology in space suit gloves.

Combined Dynamic Time Warping with Multiple Sensors for 3D Gesture Recognition.

PubMed

Choi, Hyo-Rim; Kim, TaeYong

2017-08-17

Cyber-physical systems, which closely integrate physical systems and humans, can be applied to a wider range of applications through user movement analysis. In three-dimensional (3D) gesture recognition, multiple sensors are required to recognize various natural gestures. Several studies have been undertaken in the field of gesture recognition; however, gesture recognition was conducted based on data captured from various independent sensors, which rendered the capture and combination of real-time data complicated. In this study, a 3D gesture recognition method using combined information obtained from multiple sensors is proposed. The proposed method can robustly perform gesture recognition regardless of a user's location and movement directions by providing viewpoint-weighted values and/or motion-weighted values. In the proposed method, the viewpoint-weighted dynamic time warping with multiple sensors has enhanced performance by preventing joint measurement errors and noise due to sensor measurement tolerance, which has resulted in the enhancement of recognition performance by comparing multiple joint sequences effectively.

A randomized controlled study to evaluate the role of video-based coaching in training laparoscopic skills.

PubMed

Singh, Pritam; Aggarwal, Rajesh; Tahir, Muaaz; Pucher, Philip H; Darzi, Ara

2015-05-01

This study evaluates whether video-based coaching can enhance laparoscopic surgical skills performance. Many professions utilize coaching to improve performance. The sports industry employs video analysis to maximize improvement from every performance. Laparoscopic novices were baseline tested and then trained on a validated virtual reality (VR) laparoscopic cholecystectomy (LC) curriculum. After competence, subjects were randomized on a 1:1 ratio and each performed 5 VRLCs. After each LC, intervention group subjects received video-based coaching by a surgeon, utilizing an adaptation of the GROW (Goals, Reality, Options, Wrap-up) coaching model. Control subjects viewed online surgical lectures. All subjects then performed 2 porcine LCs. Performance was assessed by blinded video review using validated global rating scales. Twenty subjects were recruited. No significant differences were observed between groups in baseline performance and in VRLC1. For each subsequent repetition, intervention subjects significantly outperformed controls on all global rating scales. Interventions outperformed controls in porcine LC1 [Global Operative Assessment of Laparoscopic Skills: (20.5 vs 15.5; P = 0.011), Objective Structured Assessment of Technical Skills: (21.5vs 14.5; P = 0.001), and Operative Performance Rating System: (26 vs 19.5; P = 0.001)] and porcine LC2 [Global Operative Assessment of Laparoscopic Skills: (28 vs 17.5; P = 0.005), Objective Structured Assessment of Technical Skills: (30 vs 16.5; P < 0.001), and Operative Performance Rating System: (36 vs 21; P = 0.004)]. Intervention subjects took significantly longer than controls in porcine LC1 (2920 vs 2004 seconds; P = 0.009) and LC2 (2297 vs 1683; P = 0.003). Despite equivalent exposure to practical laparoscopic skills training, video-based coaching enhanced the quality of laparoscopic surgical performance on both VR and porcine LCs, although at the expense of increased time. Video-based coaching is a feasible method of maximizing performance enhancement from every clinical exposure.

Enhancement/upgrade of Engine Structures Technology Best Estimator (EST/BEST) Software System

NASA Technical Reports Server (NTRS)

Shah, Ashwin

2003-01-01

This report describes the work performed during the contract period and the capabilities included in the EST/BEST software system. The developed EST/BEST software system includes the integrated NESSUS, IPACS, COBSTRAN, and ALCCA computer codes required to perform the engine cycle mission and component structural analysis. Also, the interactive input generator for NESSUS, IPACS, and COBSTRAN computer codes have been developed and integrated with the EST/BEST software system. The input generator allows the user to create input from scratch as well as edit existing input files interactively. Since it has been integrated with the EST/BEST software system, it enables the user to modify EST/BEST generated files and perform the analysis to evaluate the benefits. Appendix A gives details of how to use the newly added features in the EST/BEST software system.

CT urography of urinary diversions with enhanced CT digital radiography: preliminary experience.

PubMed

Sudakoff, Gary S; Guralnick, Michael; Langenstroer, Peter; Foley, W Dennis; Cihlar, Krista L; Shakespear, Jonathan S; See, William A

2005-01-01

The purpose of this study was to determine if 3D-rendered CT urography (CTU) depicts both normal and abnormal findings in patients with urinary diversions and if the addition of contrast-enhanced CT digital radiography (CTDR) improves opacification of the urinary collecting system. Thirty CTU and contrast-enhanced CTDR examinations were performed in 24 patients who underwent cystectomy for bladder cancer. Indications for evaluation included hematuria, tumor surveillance, or suspected diversion malfunction. All examinations were evaluated without knowledge of the stage or grade of a patient's tumor and were compared with the clinical records. Opacification of the urinary collecting system was evaluated with 3D CTU alone, contrast-enhanced CTDR alone, and combined CTU and CTDR. Nine abnormalities were identified including distal ureteral strictures (n = 4), vascular compression of the mid left ureter (n = 1), scarring of the mid right pole infundibulum (n = 1), bilateral hydronephrosis and hydroureter (n = 1), urinary reservoir calculus (n = 1), and tumor recurrence invading the afferent limb of the neobladder (n = 1). Eight of the nine detected abnormalities were surgically or pathologically confirmed. All abnormalities were identified on all three imaging techniques but were best seen on 3D CTU and enhanced CTDR images. Incomplete opacification of the urinary collecting system occurred in 17 patients with CTU alone, 12 patients with contrast-enhanced CTDR alone, and nine patients with combined CTU and contrast-enhanced CTDR. Compared with CTU alone, the combined technique of 3D CTU and contrast-enhanced CTDR improved opacification by a statistically significant difference (p = 0.037). CTU with 3D rendering can accurately depict both normal and abnormal postoperative findings in patients with urinary diversions. Adding enhanced CTDR can improve visualization of the urinary collecting system.

Guiding Principles for Stabilization and Reconstruction

DTIC Science & Technology

2009-01-01

of justice that conform with interna- tional human rights standards, and a system exists to ensure equal and effective application of the law...legisla- tive performance.434 A strong committee system that enhances lawmaking, oversight, and representation is a typical feature in effective ...transparency, and effectiveness when developing a bank- ing system . In the early stages, focus on creating a relevant, transparent, and effective

Process Time Refinement for Reusable Launch Vehicle Regeneration Modeling

DTIC Science & Technology

2008-03-01

predicted to fail, or have failed. 3) Augmenting existing space systems with redundant or additional capability to enhance space system performance or...Canopies, External Tanks/Pods/Pylon Ejectors , Armament Bay Doors, Missile Launchers, Wing and Fuselage Center Line Racks, Bomb Bay Release...Systems Test 04583 Thrust Maintenance Operation 04584 Silo Door Operation 04650 Initial Build-up-Recovery Vehicle (RV) 147 04610 Nondestructive

The Impact of Organismal Innovation on Functional and Ecological Diversification.

PubMed

Wainwright, Peter C; Price, Samantha A

2016-09-01

Innovations in organismal functional morphology are thought to be a major force in shaping evolutionary patterns, with the potential to drive adaptive radiation and influence the evolutionary prospects for lineages. But the evolutionary consequences of innovation are diverse and usually do not result in adaptive radiation. What factors shape the macroevolutionary impact of innovations? We assert that little is known in general about the macroevolutionary outcomes associated with functional innovations and we discuss a framework for studying biological innovations in an evolutionary context. Innovations are novel functional mechanisms that enhance organismal performance. The ubiquity of trade-offs in functional systems means that enhanced performance on one axis often occurs at the expense of performance on another axis, such that many innovations result in an exchange of performance capabilities, rather than an expansion. Innovations may open up new resources for exploitation but their consequences for functional and ecological diversification depend heavily on the adaptive landscape around these novel resources. As an example of a broader program that we imagine, we survey five feeding innovations in labrid fishes, an exceptionally successful and ecologically diverse group of reef fishes, and explore their impact on the rate of evolution of jaw functional morphology. All of the innovations provide performance enhancements and result in changes in patterns of resource use, but most are not associated with subsequent functional diversification or substantial ecological diversification. Because selection acts on a specific performance enhancement and not on the evolutionary potential of an innovation, the enhancement of diversity may be highly serendipitous. The macroevolutionary potential of innovations depends critically on the interaction between the performance enhancement and the ecological opportunity that is exposed. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Enhanced CAH dechlorination in a low permeability, variably-saturated medium

USGS Publications Warehouse

Martin, J.P.; Sorenson, K.S.; Peterson, L.N.; Brennan, R.A.; Werth, C.J.; Sanford, R.A.; Bures, G.H.; Taylor, C.J.; ,

2002-01-01

An innovative pilot-scale field test was performed to enhance the anaerobic reductive dechlorination (ARD) of chlorinated aliphatic hydrocarbons (CAHs) in a low permeability, variably-saturated formation. The selected technology combines the use of a hydraulic fracturing (fracking) technique with enhanced bioremediation through the creation of highly-permeable sand- and electron donor-filled fractures in the low permeability matrix. Chitin was selected as the electron donor because of its unique properties as a polymeric organic material and based on the results of lab studies that indicated its ability to support ARD. The distribution and impact of chitin- and sand-filled fractures to the system was evaluated using hydrologic, geophysical, and geochemical parameters. The results indicate that, where distributed, chitin favorably impacted redox conditions and supported enhanced ARD of CAHs. These results indicate that this technology may be a viable and cost-effective approach for remediation of low-permeability, variably saturated systems.

Understanding patient safety performance and educational needs using the 'Safety-II' approach for complex systems.

PubMed

McNab, Duncan; Bowie, Paul; Morrison, Jill; Ross, Alastair

2016-11-01

Participation in projects to improve patient safety is a key component of general practice (GP) specialty training, appraisal and revalidation. Patient safety training priorities for GPs at all career stages are described in the Royal College of General Practitioners' curriculum. Current methods that are taught and employed to improve safety often use a 'find-and-fix' approach to identify components of a system (including humans) where performance could be improved. However, the complex interactions and inter-dependence between components in healthcare systems mean that cause and effect are not always linked in a predictable manner. The Safety-II approach has been proposed as a new way to understand how safety is achieved in complex systems that may improve quality and safety initiatives and enhance GP and trainee curriculum coverage. Safety-II aims to maximise the number of events with a successful outcome by exploring everyday work. Work-as-done often differs from work-as-imagined in protocols and guidelines and various ways to achieve success, dependent on work conditions, may be possible. Traditional approaches to improve the quality and safety of care often aim to constrain variability but understanding and managing variability may be a more beneficial approach. The application of a Safety-II approach to incident investigation, quality improvement projects, prospective analysis of risk in systems and performance indicators may offer improved insight into system performance leading to more effective change. The way forward may be to combine the Safety-II approach with 'traditional' methods to enhance patient safety training, outcomes and curriculum coverage.

Enhanced bioremediation of BTEX using immobilized nutrients: Field demonstration and monitoring

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

Borden, R.C.; Goin, R.T.; Kao, C.M.

1996-12-01

A permeable barrier system was developed for controlling the migration of dissolved contaminant plumes in ground water. The barrier system consisted of a line of closely spaced wells installed perpendicular to the contaminant plume. Each well contained concrete briquets that released oxygen and nitrate at a controlled rate, enhancing the aerobic biodegradation of dissolved hydrocarbons in the downgradient aquifer. A full scale permeable barrier system was constructed at a gasoline-spill site near Leland, NC. Initially, increased dissolved oxygen and decreased benzene, toluene, ethylbenzene, and xylene isomer (BTEX) concentrations in the downgradient aquifer indicated that oxygen released from the remediation wellsmore » was enhancing biodegradation. Field tracer tests and soil analyses performed at the conclusion of the project indicated that the aquifer in the vicinity of the remediation wells was being clogged by precipitation from iron minerals.« less

Analysis of a concentric-tube robot design and feasibility for endoscopic deployment

NASA Astrophysics Data System (ADS)

Ponten, Ryan; Black, Caroline B.; Russ, Andrew J.; Rucker, D. Caleb

2017-03-01

An intraluminal endoscopic approach is desirable for most colonoscopic procedures and is growing in favor for other surgeries as tools are enhanced. Flexible robotic manipulators could further enhance the dexterity and precision of commercial endoscopic systems. In this paper, we explore the capabilities of concentric tube robots to work as tool manipulators at the tip of a colonoscope to perform endoscopic submucousal dissection (ESD) and endoscopic full thickness resection (EFTR). We provide an overview of the kinematic modeling of these manipulators, a design of a prototype manipulator and the transmission actuation system. Our analysis examines the workspace and stiffness of these manipulators being controlled at the tip of a colonoscope. We compare the results to reported surgical requirements and propose solutions for enhancing their effectiveness including notching tubes with a larger Young's Modulus. We also determine the resolution and accuracy of the actuation system.

Job design, employment practices and well-being: a systematic review of intervention studies.

PubMed

Daniels, Kevin; Gedikli, Cigdem; Watson, David; Semkina, Antonina; Vaughn, Oluwafunmilayo

2017-09-01

There is inconsistent evidence that deliberate attempts to improve job design realise improvements in well-being. We investigated the role of other employment practices, either as instruments for job redesign or as instruments that augment job redesign. Our primary outcome was well-being. Where studies also assessed performance, we considered performance as an outcome. We reviewed 33 intervention studies. We found that well-being and performance may be improved by: training workers to improve their own jobs; training coupled with job redesign; and system wide approaches that simultaneously enhance job design and a range of other employment practices. We found insufficient evidence to make any firm conclusions concerning the effects of training managers in job redesign and that participatory approaches to improving job design have mixed effects. Successful implementation of interventions was associated with worker involvement and engagement with interventions, managerial commitment to interventions and integration of interventions with other organisational systems. Practitioner Summary: Improvements in well-being and performance may be associated with system-wide approaches that simultaneously enhance job design, introduce a range of other employment practices and focus on worker welfare. Training may have a role in initiating job redesign or augmenting the effects of job design on well-being.

INTEGRATED INS/GPS NAVIGATION FROM A POPULAR PERSPECTIVE

DOT National Transportation Integrated Search

2002-02-13

Inertial navigation, blended with other navigation aids Global Positioning System (GPS) in particular, has gained significance due to enhanced navigation and inertial reference performance and dissimilarity for fault tolerance and anti-jamming. Relat...

Structural dynamic interaction with solar tracking control for evolutionary Space Station concepts

NASA Technical Reports Server (NTRS)

Lim, Tae W.; Cooper, Paul A.; Ayers, J. Kirk

1992-01-01

The sun tracking control system design of the Solar Alpha Rotary Joint (SARJ) and the interaction of the control system with the flexible structure of Space Station Freedom (SSF) evolutionary concepts are addressed. The significant components of the space station pertaining to the SARJ control are described and the tracking control system design is presented. Finite element models representing two evolutionary concepts, enhanced operations capability (EOC) and extended operations capability (XOC), are employed to evaluate the influence of low frequency flexible structure on the control system design and performance. The design variables of the control system are synthesized using a constrained optimization technique to meet design requirements, to provide a given level of control system stability margin, and to achieve the most responsive tracking performance. The resulting SARJ control system design and performance of the EOC and XOC configurations are presented and compared to those of the SSF configuration. Performance limitations caused by the low frequency of the dominant flexible mode are discussed.

Comparison of display enhancement with intelligent decision-aiding

NASA Technical Reports Server (NTRS)

Kirlik, Alex; Markert, Wendy J.; Kossack, Merrick

1992-01-01

Currently, two main approaches exist for improving the human-machine interface component of a system in order to improve overall system performance, display enhancement and intelligent decision aiding. Each of these two approaches has its own set of advantages and disadvantages, as well as introduce its own set of additional performance problems. These characteristics should help identify which types of problem situations and domains are better aided by which type of strategy. The characteristic issues are described of these two decision aiding strategies. Then differences in expert and novice decision making are described in order to help determine whether a particular strategy may be better for a particular type of user. Finally, research is outlined to compare and contrast the two technologies, as well as to examine the interaction effects introduced by the different skill levels and the different methods for training operators.

Contribution of prior semantic knowledge to new episodic learning in amnesia.

PubMed

Kan, Irene P; Alexander, Michael P; Verfaellie, Mieke

2009-05-01

We evaluated whether prior semantic knowledge would enhance episodic learning in amnesia. Subjects studied prices that are either congruent or incongruent with prior price knowledge for grocery and household items and then performed a forced-choice recognition test for the studied prices. Consistent with a previous report, healthy controls' performance was enhanced by price knowledge congruency; however, only a subset of amnesic patients experienced the same benefit. Whereas patients with relatively intact semantic systems, as measured by an anatomical measure (i.e., lesion involvement of anterior and lateral temporal lobes), experienced a significant congruency benefit, patients with compromised semantic systems did not experience a congruency benefit. Our findings suggest that when prior knowledge structures are intact, they can support acquisition of new episodic information by providing frameworks into which such information can be incorporated.

Heterogeneous concurrent computing with exportable services

NASA Technical Reports Server (NTRS)

Sunderam, Vaidy

1995-01-01

Heterogeneous concurrent computing, based on the traditional process-oriented model, is approaching its functionality and performance limits. An alternative paradigm, based on the concept of services, supporting data driven computation, and built on a lightweight process infrastructure, is proposed to enhance the functional capabilities and the operational efficiency of heterogeneous network-based concurrent computing. TPVM is an experimental prototype system supporting exportable services, thread-based computation, and remote memory operations that is built as an extension of and an enhancement to the PVM concurrent computing system. TPVM offers a significantly different computing paradigm for network-based computing, while maintaining a close resemblance to the conventional PVM model in the interest of compatibility and ease of transition Preliminary experiences have demonstrated that the TPVM framework presents a natural yet powerful concurrent programming interface, while being capable of delivering performance improvements of upto thirty percent.

BiCuSeO Thermoelectrics: An Update on Recent Progress and Perspective

PubMed Central

Zhang, Xiaoxuan; Chang, Cheng; Zhou, Yiming; Zhao, Li-Dong

2017-01-01

A BiCuSeO system has been reported as a promising thermoelectric material and has attracted great attention in the thermoelectric community since 2010. Recently, several remarkable studies have been reported and the ZT of BiCuSeO was pushed to a higher level. It motivates us to systematically summarize the recent reports on the BiCuSeO system. In this short review, we start with several attempts to optimize thermoelectric properties of BiCuSeO. Then, we introduce several opinions to explore the origins of low thermal conductivity for BiCuSeO. Several approaches to enhance thermoelectric performance are also summarized, including modulation doping, introducing dual-vacancies, and dual-doping, etc. At last, we propose some possible strategies for enhancing thermoelectric performance of BiCuSeO in future research. PMID:28772557

Enhanced two phase flow in heat transfer systems

DOEpatents

Tegrotenhuis, Ward E; Humble, Paul H; Lavender, Curt A; Caldwell, Dustin D

2013-12-03

A family of structures and designs for use in devices such as heat exchangers so as to allow for enhanced performance in heat exchangers smaller and lighter weight than other existing devices. These structures provide flow paths for liquid and vapor and are generally open. In some embodiments of the invention, these structures can also provide secondary heat transfer as well. In an evaporate heat exchanger, the inclusion of these structures and devices enhance the heat transfer coefficient of the evaporation phase change process with comparable or lower pressure drop.

Giant Enhancement of Small Photoluminescent Signals on Glass Surfaces Covered by Self-Assembled Silver Nanorings.

PubMed

Sousanis, A; Poulopoulos, P; Karoutsos, V; Trachylis, D; Politis, C

2017-02-01

Self-assembled nanostructures with the shape of nanospheres or nanorings were formed after annealing of ultrathin Ag films grown on glass, in a furnace with air at 460 °C. Intense localized surface plasmon resonances were recorded for these nanostructures with maxima at the green-blue light. The surface became functional in terms of enhancing the weak photoluminescence of glass between 2–400 times. This system provides an easy way of enhancing the photoluminescence emission of initially low performance materials.

Low-temperature, ultrahigh-vacuum tip-enhanced Raman spectroscopy combined with molecular beam epitaxy for in situ two-dimensional materials' studies

NASA Astrophysics Data System (ADS)

Sheng, Shaoxiang; Li, Wenbin; Gou, Jian; Cheng, Peng; Chen, Lan; Wu, Kehui

2018-05-01

Tip-enhanced Raman spectroscopy (TERS), which combines scanning probe microscopy with the Raman spectroscopy, is capable to access the local structure and chemical information simultaneously. However, the application of ambient TERS is limited by the unstable and poorly controllable experimental conditions. Here, we designed a high performance TERS system based on a low-temperature ultrahigh-vacuum scanning tunneling microscope (LT-UHV-STM) and combined with a molecular beam epitaxy (MBE) system. It can be used for growing two-dimensional (2D) materials and for in situ STM and TERS characterization. Using a 2D silicene sheet on the Ag(111) surface as a model system, we achieved an unprecedented 109 Raman single enhancement factor in combination with a TERS spatial resolution down to 0.5 nm. The results show that TERS combined with a MBE system can be a powerful tool to study low dimensional materials and surface science.

MEMS Using SOI Substrate

NASA Technical Reports Server (NTRS)

Tang, Tony K.

1999-01-01

At NASA, the focus for smaller, less costly missions has given impetus for the development of microspacecraft. MicroElectroMechanical System (MEMS) technology advances in the area of sensor, propulsion systems, and instruments, make the notion of a specialized microspacecraft feasible in the immediate future. Similar to the micro-electronics revolution,the emerging MEMS technology offers the integration of recent advances in micromachining and nanofabrication techniques with microelectronics in a mass-producible format,is viewed as the next step in device and instrument miniaturization. MEMS technology offers the potential of enabling or enhancing NASA missions in a variety of ways. This new technology allows the miniaturization of components and systems, where the primary benefit is a reduction in size, mass and power. MEMS technology also provides new capabilities and enhanced performance, where the most significant impact is in performance, regardless of system size. Finally,with the availability of mass-produced, miniature MEMS instrumentation comes the opportunity to rethink our fundamental measurement paradigms. It is now possible to expand our horizons from a single instrument perspective to one involving multi-node distributed systems. In the distributed systems and missions, a new system in which the functionality is enabled through a multiplicity of elements. Further in the future, the integration of electronics, photonics, and micromechanical functionalities into "instruments-on-a-chip" will provide the ultimate size, cost, function, and performance advantage. In this presentation, I will discuss recent development, requirement, and applications of various MEMS technologies and devices for space applications.

Enhanced Engine Control for Emergency Operation

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.

2012-01-01

C-MAPSS40k engine simulation has been developed and is available to the public. The authenticity of the engine performance and controller enabled the development of realistic enhanced control modes through controller modification alone. Use of enhanced control modes improved stability and control of an impaired aircraft. - Fast Response is useful for manual manipulation of the throttles - Use of Fast Response improved stability as part of a yaw rate feedback system. - Use of Overthrust shortened takeoff distance, but was generally useful in flight, too. Initial lack of pilot familiarity resulted in discomfort, especially with yaw rate feedback, but that was the only drawback, overall the pilot found the enhanced modes very helpful.

A Risk Management Architecture for Emergency Integrated Aircraft Control

NASA Technical Reports Server (NTRS)

McGlynn, Gregory E.; Litt, Jonathan S.; Lemon, Kimberly A.; Csank, Jeffrey T.

2011-01-01

Enhanced engine operation--operation that is beyond normal limits--has the potential to improve the adaptability and safety of aircraft in emergency situations. Intelligent use of enhanced engine operation to improve the handling qualities of the aircraft requires sophisticated risk estimation techniques and a risk management system that spans the flight and propulsion controllers. In this paper, an architecture that weighs the risks of the emergency and of possible engine performance enhancements to reduce overall risk to the aircraft is described. Two examples of emergency situations are presented to demonstrate the interaction between the flight and propulsion controllers to facilitate the enhanced operation.

Technology evaluation report: SITE (Superfund Innovative Technology Evaluation) program demonstration test. The American Combustion Pyretron Thermal Destruction System at the US EPA's (Environmental Protection Agency's) combustion research facility

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

Waterland, L.; Lee, J.W.

1989-04-01

A series of demonstration tests of the American Combustion, Inc., Thermal Destruction System was performed under the SITE program. This oxygen-enhanced combustion system was retrofit to the rotary-kiln incinerator at EPA's Combustion Research Facility. The system's performance was tested firing contaminated soil from the Stringfellow Superfund Site, both alone and mixed with a coal tar waste (KO87). Comparative performance with conventional incinerator operation was also tested. Compliance with the incinerator performance standards of 99.99% principal organic hazardous constituents (POHC) destruction and removal efficiency and particulate emissions of less than 180 mg/dscm at 7% O2 was measured for all tests. Themore » Pyretron system was capable of in-compliance performance at double the mixed waste feedrate and at a 60% increase in batch waste charge mass than possible with conventional incineration. Scrubber blowdown and kiln ash contained no detectable levels of any of the POHCs chosen.« less

Numerical Evaluation of an Ejector-Enhanced Resonant Pulse Combustor with a Poppet Inlet Valve and a Converging Exhaust Nozzle

NASA Technical Reports Server (NTRS)

Yungster, Shaye; Paxson, Daniel E.; Perkins, Hugh D.

2016-01-01

A computational investigation of a pressure-gain combustor system for gas turbine applications is presented. The system consists of a valved pulse combustor and an ejector, housed within a shroud. The study focuses on two enhancements to previous models, related to the valve and ejector components. First, a new poppet inlet valve system is investigated, replacing the previously used reed valve configuration. Secondly, a new computational approach to approximating the effects of choked turbine inlet guide vanes present immediately downstream of the Ejector-Enhanced Resonant Pulse Combustor (EERPC) is investigated. Instead of specifying a back pressure at the EERPC exit boundary (as was done in previous studies) the new model adds a converging-diverging (CD) nozzle at the exit of the EERPC. The throat area of the CD nozzle can be adjusted to obtain the desired back pressure level and total mass flow rate. The results presented indicate that the new poppet valve configuration performs nearly as well as the original reed valve system, and that the addition of the CD nozzle is an effective method to approximate the exit boundary effects of a turbine present downstream of the EERPC. Furthermore, it is shown that the more acoustically reflective boundary imposed by a nozzle as compared to a constant pressure surface does not significantly affect operation or performance.

Location-Enhanced Activity Recognition in Indoor Environments Using Off the Shelf Smart Watch Technology and BLE Beacons

PubMed Central

Filippoupolitis, Avgoustinos; Oliff, William; Takand, Babak; Loukas, George

2017-01-01

Activity recognition in indoor spaces benefits context awareness and improves the efficiency of applications related to personalised health monitoring, building energy management, security and safety. The majority of activity recognition frameworks, however, employ a network of specialised building sensors or a network of body-worn sensors. As this approach suffers with respect to practicality, we propose the use of commercial off-the-shelf devices. In this work, we design and evaluate an activity recognition system composed of a smart watch, which is enhanced with location information coming from Bluetooth Low Energy (BLE) beacons. We evaluate the performance of this approach for a variety of activities performed in an indoor laboratory environment, using four supervised machine learning algorithms. Our experimental results indicate that our location-enhanced activity recognition system is able to reach a classification accuracy ranging from 92% to 100%, while without location information classification accuracy it can drop to as low as 50% in some cases, depending on the window size chosen for data segmentation. PMID:28555022

Enhanced Performance of Community Health Service Centers during Medical Reforms in Pudong New District of Shanghai, China: A Longitudinal Survey.

PubMed

Sun, Xiaoming; Li, Yanting; Liu, Shanshan; Lou, Jiquan; Ding, Ye; Liang, Hong; Gu, Jianjun; Jing, Yuan; Fu, Hua; Zhang, Yimin

2015-01-01

The performance of community health service centers (CHSCs) has not been well monitored and analysed since China's latest community health reforms in 2009. The aim of the current investigation was to evaluate the performing trends of the CHSCs and to analyze the main factors that could affect the performance in Pudong new district of Shanghai, China. A regional performance assessment indicator system was applied to the evaluation of Pudong CHSCs' performance from 2011 to 2013. All of the data were sorted out by a panel, and analyzed using descriptive statistics and a generalized estimating equation model. We found that the overall performance increased annually, with a growing number of CHSCs achieving high scores. Significant differences were observed in institutional management, public health services, basic medical services and comprehensive satisfaction during the period of three years. However, we found no differences in the service scores of Chinese traditional medicine (CTM). The investigation also demonstrated that the key factors affecting performance were the location, information system level, family GP program and medical association program rather than the size of the center. However, the medical association participation appeared to have a significant negative effect on performance. It can be concluded from the three-year investigation that the overall performance was improved, but that it could have been further enhanced, especially in institutional management and basic medical service; therefore, it is imperative that CHSCs undertake approaches such as optimizing the resource allocation and utilization, reinforcing the establishment of the information system level, extending the family GP program to more local communities, and promoting the medical association initiative.

Development of mpi_EPIC model for global agroecosystem modeling

DOE PAGES

Kang, Shujiang; Wang, Dali; Jeff A. Nichols; ...

2014-12-31

Models that address policy-maker concerns about multi-scale effects of food and bioenergy production systems are computationally demanding. We integrated the message passing interface algorithm into the process-based EPIC model to accelerate computation of ecosystem effects. Simulation performance was further enhanced by applying the Vampir framework. When this enhanced mpi_EPIC model was tested, total execution time for a global 30-year simulation of a switchgrass cropping system was shortened to less than 0.5 hours on a supercomputer. The results illustrate that mpi_EPIC using parallel design can balance simulation workloads and facilitate large-scale, high-resolution analysis of agricultural production systems, management alternatives and environmentalmore » effects.« less

MSFC Skylab Apollo Telescope Mount summary mission report

NASA Technical Reports Server (NTRS)

Morse, A. R.

1974-01-01

A summary of the Apollo Telescope Mount (ATM) performance during the 8.5-month Skylab mission is presented. A brief description of each ATM system, system performance summaries, discussion of all significant ATM anomalies which occurred during the Skylab mission, and, in an appendix, a summary of the Skylab ATM Calibration Rocket Project (CALROC) are provided. The text is supplemented and amplified by photographs, drawings, curves, and tables. The report shows that the ATM not only met, but exceeded premission performance criteria, and that participation of man in space for this scientific investigation greatly enhanced the quality and quantity of the data attained.

Assessment of three different software systems in the evaluation of dynamic MRI of the breast.

PubMed

Kurz, K D; Steinhaus, D; Klar, V; Cohnen, M; Wittsack, H J; Saleh, A; Mödder, U; Blondin, D

2009-02-01

The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ("CADstream" and "3TP") and one self-developed software system ("Mammatool"). Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. "CADstream" showed the best score on subjective quality criteria. "3TP" showed the lowest number of false-positive results. "Mammatool" produced the lowest number of benign tissues indicated with parametric overlay. All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable.

Advanced Earth-to-orbit propulsion technology program overview: Impact of civil space technology initiative

NASA Technical Reports Server (NTRS)

Stephenson, Frank W., Jr.

1988-01-01

The NASA Earth-to-Orbit (ETO) Propulsion Technology Program is dedicated to advancing rocket engine technologies for the development of fully reusable engine systems that will enable space transportation systems to achieve low cost, routine access to space. The program addresses technology advancements in the areas of engine life extension/prediction, performance enhancements, reduced ground operations costs, and in-flight fault tolerant engine operations. The primary objective is to acquire increased knowledge and understanding of rocket engine chemical and physical processes in order to evolve more realistic analytical simulations of engine internal environments, to derive more accurate predictions of steady and unsteady loads, and using improved structural analyses, to more accurately predict component life and performance, and finally to identify and verify more durable advanced design concepts. In addition, efforts were focused on engine diagnostic needs and advances that would allow integrated health monitoring systems to be developed for enhanced maintainability, automated servicing, inspection, and checkout, and ultimately, in-flight fault tolerant engine operations.

Cardinality enhancement utilizing Sequential Algorithm (SeQ) code in OCDMA system

NASA Astrophysics Data System (ADS)

Fazlina, C. A. S.; Rashidi, C. B. M.; Rahman, A. K.; Aljunid, S. A.

2017-11-01

Optical Code Division Multiple Access (OCDMA) has been important with increasing demand for high capacity and speed for communication in optical networks because of OCDMA technique high efficiency that can be achieved, hence fibre bandwidth is fully used. In this paper we will focus on Sequential Algorithm (SeQ) code with AND detection technique using Optisystem design tool. The result revealed SeQ code capable to eliminate Multiple Access Interference (MAI) and improve Bit Error Rate (BER), Phase Induced Intensity Noise (PIIN) and orthogonally between users in the system. From the results, SeQ shows good performance of BER and capable to accommodate 190 numbers of simultaneous users contrast with existing code. Thus, SeQ code have enhanced the system about 36% and 111% of FCC and DCS code. In addition, SeQ have good BER performance 10-25 at 155 Mbps in comparison with 622 Mbps, 1 Gbps and 2 Gbps bit rate. From the plot graph, 155 Mbps bit rate is suitable enough speed for FTTH and LAN networks. Resolution can be made based on the superior performance of SeQ code. Thus, these codes will give an opportunity in OCDMA system for better quality of service in an optical access network for future generation's usage

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.

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

Method and apparatus for enhancing reactor air-cooling system performance

DOEpatents

Hunsbedt, A.

1996-03-12

An enhanced decay heat removal system is disclosed for removing heat from the inert gas-filled gap space between the reactor vessel and the containment vessel of a liquid metal-cooled nuclear reactor. Multiple cooling ducts in flow communication with the inert gas-filled gap space are incorporated to provide multiple flow paths for the inert gas to circulate to heat exchangers which remove heat from the inert gas, thereby introducing natural convection flows in the inert gas. The inert gas in turn absorbs heat directly from the reactor vessel by natural convection heat transfer. 6 figs.

The Impacts of Changes to Nevada’s Net Metering Policy on the Financial Performance and Adoption of Distributed Photovoltaics

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

Gagnon, Pieter; Sigrin, Ben; Gleason, Mike

Net energy metering (NEM) is a billing mechanism that has historically compensated owners of distributed generation systems at retail rates for any electricity that they export back to the grid rather than consume on-site. NEM can significantly enhance the financial performance of distributed generation systems from the owner’s perspective. The following analysis was designed to illustrate the potential impact of NEM policy and tariff changes implemented in early 2016 in Nevada.

SoC: Une Nouvelle Approche de l’Amelioration des Performances des Systemes pour Combattre les Problemes de Disponibilite a Long Terme (SoC: A New Approach to Enhance System Performances and to Combat the Long-Term Availability Issue)

DTIC Science & Technology

2001-01-01

cin~tique Properties»> ou o IP »>. En fait, ces IP ne sont rien (exemple : un missile en vol libre ). Meme si on peut d’autres que des composants sur...probablement pas radicalement le problkme peuvent soit achet~s soit &tre issus de conceptions au niveau des composants 6lectroniques. pr&c~dentes. Les

Impaired Memory Retrieval Correlates with Individual Differences in Cortisol Response but Not Autonomic Response

ERIC Educational Resources Information Center

Tranel, Daniel; Adolphs, Ralph; Buchanan, Tony W.

2006-01-01

Stress can enhance or impair memory performance. Both cortisol release and sympathetic nervous system responses have been implicated in these differential effects. Here we investigated how memory retrieval might be affected by stress-induced cortisol release, independently of sympathetic nervous system stress responses. Thirty-two healthy…

Smart Homes and Buildings Research at the Energy Systems Integration Facility

ScienceCinema

Christensen, Dane; Sparn, Bethany; Hannegan, Bryan

2018-01-16

Watch how NREL researchers are using the unique capabilities of the Energy Systems Integration Facility (ESIF) to develop technologies that will help the “smart” homes and buildings of the future perform efficiently and communicate effectively with the electricity grid while enhancing occupants' comfort and convenience.

76 FR 8278 - Special Conditions: Gulfstream Model GVI Airplane; Enhanced Flight Vision System

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-14

... detected by infrared sensors can be much different from that detected by natural pilot vision. On a dark... by many imaging infrared systems. On the other hand, contrasting colors in visual wavelengths may be... of the EFVS image and the level of EFVS infrared sensor performance could depend significantly on...

Understanding Usefulness in Human-Computer Interaction to Enhance User Experience Evaluation

ERIC Educational Resources Information Center

MacDonald, Craig Matthew

2012-01-01

The concept of usefulness has implicitly played a pivotal role in evaluation research, but the meaning of usefulness has changed over time from system reliability to user performance and learnability/ease of use for non-experts. Despite massive technical and social changes, usability remains the "gold standard" for system evaluation.…

Principals' Instructional Leadership within a Teacher Performance Appraisal System: Enhancing Students' Academic Success

ERIC Educational Resources Information Center

Ovando, Martha N.; Ramirez, Alfredo, Jr.

2007-01-01

The purpose of this study was to identify principals' instructional leadership actions within a comprehensive teacher evaluation system in successful schools rated as recognized or exemplary by the accountability measures in place. The study followed a multiple case study approach. Participants included six school administrators within the same…

Application of expert systems in project management decision aiding

NASA Technical Reports Server (NTRS)

Harris, Regina; Shaffer, Steven; Stokes, James; Goldstein, David

1987-01-01

The feasibility of developing an expert systems-based project management decision aid to enhance the performance of NASA project managers was assessed. The research effort included extensive literature reviews in the areas of project management, project management decision aiding, expert systems technology, and human-computer interface engineering. Literature reviews were augmented by focused interviews with NASA managers. Time estimation for project scheduling was identified as the target activity for decision augmentation, and a design was developed for an Integrated NASA System for Intelligent Time Estimation (INSITE). The proposed INSITE design was judged feasible with a low level of risk. A partial proof-of-concept experiment was performed and was successful. Specific conclusions drawn from the research and analyses are included. The INSITE concept is potentially applicable in any management sphere, commercial or government, where time estimation is required for project scheduling. As project scheduling is a nearly universal management activity, the range of possibilities is considerable. The INSITE concept also holds potential for enhancing other management tasks, especially in areas such as cost estimation, where estimation-by-analogy is already a proven method.

Enhancing performance of LCoS-SLM as adaptive optics by using computer-generated holograms modulation software

NASA Astrophysics Data System (ADS)

Tsai, Chun-Wei; Lyu, Bo-Han; Wang, Chen; Hung, Cheng-Chieh

2017-05-01

We have already developed multi-function and easy-to-use modulation software that was based on LabVIEW system. There are mainly four functions in this modulation software, such as computer generated holograms (CGH) generation, CGH reconstruction, image trimming, and special phase distribution. Based on the above development of CGH modulation software, we could enhance the performance of liquid crystal on silicon - spatial light modulator (LCoSSLM) as similar as the diffractive optical element (DOE) and use it on various adaptive optics (AO) applications. Through the development of special phase distribution, we are going to use the LCoS-SLM with CGH modulation software into AO technology, such as optical microscope system. When the LCOS-SLM panel is integrated in an optical microscope system, it could be placed on the illumination path or on the image forming path. However, LCOS-SLM provides a program-controllable liquid crystal array for optical microscope. It dynamically changes the amplitude or phase of light and gives the obvious advantage, "Flexibility", to the system

Simultaneous radiofrequency (RF) heating and magnetic resonance (MR) thermal mapping using an intravascular MR imaging/RF heating system.

PubMed

Qiu, Bensheng; El-Sharkawy, Abdel-Monem; Paliwal, Vaishali; Karmarkar, Parag; Gao, Fabao; Atalar, Ergin; Yang, Xiaoming

2005-07-01

Previous studies have confirmed the possibility of using an intravascular MR imaging guidewire (MRIG) as a heating source to enhance vascular gene transfection/expression. This motivated us to develop a new intravascular system that can perform MR imaging, radiofrequncy (RF) heating, and MR temperature monitoring simultaneously in an MR scanner. To validate this concept, a series of mathematical simulations of RF power loss along a 0.032-inch MRIG and RF energy spatial distribution were performed to determine the optimum RF heating frequency. Then, an RF generator/amplifier and a filter box were built. The possibility for simultaneous RF heating and MR thermal mapping of the system was confirmed in vitro using a phantom, and the obtained thermal mapping profile was compared with the simulated RF power distribution. Subsequently, the feasibility of simultaneous RF heating and temperature monitoring was successfully validated in vivo in the aorta of living rabbits. This MR imaging/RF heating system offers a potential tool for intravascular MR-mediated, RF-enhanced vascular gene therapy.

Emergency Locator Transmitter Survivability and Reliability Study

NASA Technical Reports Server (NTRS)

Stimson, Chad M.; Littell, Justin D.; Mazzuca, Lisa M.; Foster, Anthony W.; Theodorakos, George J.

2017-01-01

A comprehensive study of Emergency Locator Transmitter (ELT) performance was conducted over a three year period concluding in 2016 in support of the Search and Rescue (SAR) Mission Office at National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC). The study began with a review of reported performance cited in a collection of works published as early as 1980 as well as analysis of a focused set of contemporary aviation crash reports. Based on initial research findings, a series of subscale and fullscale system tests were performed at NASA Langley Research Center (LaRC) with the goals of investigating ELT system failure modes and developing recommended improvements to the Radio Technical Commission for Aeronautics (RTCA) Minimum Operational Performance Specification (MOPS) that will result in improved system performance. Enhanced performance of ELT systems in aviation accidents will reduce unnecessary loss of human life and make SAR operations safer and less costly by reducing the amount of time required to locate accident sites.

Developments in the design, analysis, and fabrication of advanced technology transmission elements

NASA Technical Reports Server (NTRS)

Drago, R. J.; Lenski, J. W., Jr.

1982-01-01

Over the last decade, the presently reported proprietary development program for the reduction of helicopter drive system weight and cost and the enhancement of reliability and survivability has produced high speed roller bearings, resin-matrix composite rotor shafts and transmission housings, gear/bearing/shaft system integrations, photoelastic investigation methods for gear tooth strength, and the automatic generation of complex FEM models for gear/shaft systems. After describing the design features and performance capabilities of the hardware developed, attention is given to the prospective benefits to be derived from application of these technologies, with emphasis on the relationship between helicopter drive system performance and cost.

NEXT Ion Propulsion System Development Status and Capabilities

NASA Technical Reports Server (NTRS)

Patterson, Michael J.; Benson, Scott W.

2008-01-01

NASA s Evolutionary Xenon Thruster (NEXT) project is developing next generation ion propulsion technologies to provide future NASA science missions with enhanced mission performance benefit at a low total development cost. The objective of the NEXT project is to advance next generation ion propulsion technology by producing engineering model system components, validating these through qualification-level and integrated system testing, and ensuring preparedness for transitioning to flight system development. As NASA s Evolutionary Xenon Thruster technology program completes advanced development activities, it is advantageous to review the existing technology capabilities of the system under development. This paper describes the NEXT ion propulsion system development status, characteristics and performance. A review of mission analyses results conducted to date using the NEXT system is also provided.

Cancer Care Ontario and integrated cancer programs: portrait of a performance management system and lessons learned.

PubMed

Cheng, Siu Mee; Thompson, Leslee J

2006-01-01

A performance management system has been implemented by Cancer Care Ontario (CCO). This system allows for the monitoring and management of 11 integrated cancer programs (ICPs) across the Province of Ontario. The system comprises of four elements: reporting frequency, reporting requirements, review meetings and accountability and continuous improvement activities. CCO and the ICPs have recently completed quarterly performance review exercises for the last two quarters of the fiscal year 2004-2005. The purpose of this paper is to address some of the key lessons learned. The paper provides an outline of the CCO performance management system. These lessons included: data must be valid and reliable; performance management requires commitments from both parties in the performance review exercises; streamlining performance reporting is beneficial; technology infrastructure which allows for cohesive management of data is vital for a sustainable performance management system; performance indicators need to stand up to scrutiny by both parties; and providing comparative data across the province is valuable. Critical success factors which would help to ensure a successful performance management system include: corporate engagement from various parts of an organization in the review exercises; desire to focus on performance improvement and avoidance of blaming; and strong data management systems. The performance management system is a practical and sustainable system that allows for performance improvement of cancer care services. It can be a vital tool to enhance accountability within the health care system. The paper demonstrates that the performance management system supports accountability in the cancer care system for Ontario, and reflects the principles of the provincial governments commitment to continuous improvement of healthcare.

Enhancing the Retrieval Effectiveness of Large Information Systems. Final Report for the Period 1 June 1975-31 December 1976.

ERIC Educational Resources Information Center

Becker, David S.; Pyrce, Sharon R.

The goal of this project was to find ways of enhancing the efficiency of searching machine readable data bases. Ways are sought to transfer to the computer some of the tasks that are normally performed by the user, i.e., to further automate information retrieval. Four experiments were conducted to test the feasibility of a sequential processing…

A holistic approach to movement education in sport and fitness: a systems based model.

PubMed

Polsgrove, Myles Jay

2012-01-01

The typical model used by movement professionals to enhance performance relies on the notion that a linear increase in load results in steady and progressive gains, whereby, the greater the effort, the greater the gains in performance. Traditional approaches to movement progression typically rely on the proper sequencing of extrinsically based activities to facilitate the individual in reaching performance objectives. However, physical rehabilitation or physical performance rarely progresses in such a linear fashion; instead they tend to evolve non-linearly and rather unpredictably. A dynamic system can be described as an entity that self-organizes into increasingly complex forms. Applying this view to the human body, practitioners could facilitate non-linear performance gains through a systems based programming approach. Utilizing a dynamic systems view, the Holistic Approach to Movement Education (HADME) is a model designed to optimize performance by accounting for non-linear and self-organizing traits associated with human movement. In this model, gains in performance occur through advancing individual perspectives and through optimizing sub-system performance. This inward shift of the focus of performance creates a sharper self-awareness and may lead to more optimal movements. Copyright © 2011 Elsevier Ltd. All rights reserved.

Myths and realities of electronics maintenance.

PubMed

Harris, Douglas H

2008-06-01

The author presents and discusses discoveries and developments contributing to enhanced electronics maintenance performance. This body of research is viewed from the vantage point of Nick Bond's 1970 Ely Award-winning article in Human Factors, "Some Persistent Myths About Military Electronics Maintenance." Bond identified a set of myths and summarized research that not only produced information and techniques leading to demonstrably improved maintenance performance but also exploded many unfounded beliefs that were commonly held before the research had been conducted and the findings disseminated. The period from 1964 through 1986, as reflected by publications in the journal, was a productive period of research that led to greater understanding of human factors in electronics maintenance and to numerous advances that contributed, ultimately, to more effective maintenance performance. Technological advances, combined with what we learned about maintenance performance, have substantially reduced the maintenance burden and enhanced the maintenance of electronic systems. Some of the principal lessons learned from this research on electronics maintenance apply to understanding the effects of equipment complexity, providing an optimal role for automation, designing more appropriate on-the-job training, and enhancing troubleshooting skills.

Revolutionary Design for Astronaut Exploration — Beyond the Bio-Suit System

NASA Astrophysics Data System (ADS)

Newman, Dava J.; Canina, Marita; Trotti, Guillermo L.

2007-01-01

The Bio-Suit System is designed to revolutionize human space exploration by providing enhanced astronaut extravehicular activity (EVA) locomotion and performance based on the concepts of a `second skin' capability. The novel Bio-Suit concept provides an overall exploration system realized through symbiotic relationships between a suite of advanced technologies, creative design, human modeling and analysis, and new mission operations techniques. By working at the intersection of engineering, design, life sciences and operations, new emergent capabilities and interrelationships result for applications to space missions, medical rehabilitation, and extreme sports activities. In many respects, the Bio-Suit System mimics Nature (biomimetics). For example, the second skin is capable of augmenting our biological skin by providing mechanical counter-pressure. We have designed and tested prototypes that prove mechanical counter-pressure feasibility. The `epidermis' of our second skin suit is patterned from 3D laser scans that incorporate human skin strain field maps for maximum mobility and natural movements, while requiring minimum energy expenditure for exploration tasks. We provide a technology roadmap for future design, pressure production and technology investments for the Bio-Suit System. Woven into the second skin are active materials to enhance human performance as well as to provide necessary performance metrics (i.e., energy expenditure). Wearable technologies will be embedded throughout the Bio-Suit System to place the explorer in an information-rich environment enabling real-time mission planning, prediction, and visualization. The Bio-Suit System concept augments human capabilities by coupling human and robotic abilities into a hybrid of the two, to the point where the explorer is hardly aware of the boundary between innate human performance and robotic activities.

Self-microemulsifying smaller molecular volume oil (Capmul MCM) using non-ionic surfactants: a delivery system for poorly water-soluble drug.

PubMed

Bandivadeka, Mithun Mohanraor; Pancholi, Shyam Sundar; Kaul-Ghanekar, Ruchika; Choudhari, Amit; Koppikar, Soumya

2012-07-01

The main purpose of this work is to formulate self-microemulsifying drug delivery system (SMEDDS) using smaller molecular oil with Atorvastatin calcium as a model drug. Solubility of the selected drug was accessed in oils and surfactants. Percent transmittance (%T) test study was performed to identify the efficient self-microemulsifying formulations. Those formulations which showed higher value for %T were evaluated for droplet size, polydispersity index, ζ potential, refractive index and cloud point measurement. Effect of drug loading on droplet size, increasing dilution in different media, thermodynamic stability and in vitro dissolution was performed to observe the performance of the selected formulation. Further cytotoxicity and permeation enhancement studies were carried out on Caco2 cell lines. Of all the oils accessed for drug solubility, Capmul MCM showed higher solubility capacity for Atorvastatin calcium. Capmul MCM was better microemulsified using combination of Tween 20 and Labrasol surfactant. Droplet size was as low as 86.93 nm with polydispersity index and ζ potential at 0.195 ± 0.011 and -7.27 ± 3.11 mV respectively. The selected undiluted formulation showed refractive index values ranging from 1.40 to 1.47 indicating the isotropicity of the formulation. The selected formulation was robust to dilution in different media and thermodynamically stable. Dissolution profile was enhanced for the selected drug as compared to marketed formulation with t85% and DE values at 10 min and 80.15 respectively. Also cytotoxicity measurement showed minimum effect with good permeation enhancing capacity. Thus our study demonstrates the use of smaller molecular oil (Capmul MCM) for developing self-microemulsifying drug delivery system for better in vitro and in vivo performance.

Virtual Reality and Computer-Enhanced Training Devices Equally Improve Laparoscopic Surgical Skill in Novices

PubMed Central

Kanumuri, Prathima; Ganai, Sabha; Wohaibi, Eyad M.; Bush, Ronald W.; Grow, Daniel R.

2008-01-01

Background: The study aim was to compare the effectiveness of virtual reality and computer-enhanced video-scopic training devices for training novice surgeons in complex laparoscopic skills. Methods: Third-year medical students received instruction on laparoscopic intracorporeal suturing and knot tying and then underwent a pretraining assessment of the task using a live porcine model. Students were then randomized to objectives-based training on either the virtual reality (n=8) or computer-enhanced (n=8) training devices for 4 weeks, after which the assessment was repeated. Results: Posttraining performance had improved compared with pretraining performance in both task completion rate (94% versus 18%; P<0.001*) and time [181±58 (SD) versus 292±24*]. Performance of the 2 groups was comparable before and after training. Of the subjects, 88% thought that haptic cues were important in simulators. Both groups agreed that their respective training systems were effective teaching tools, but computer-enhanced device trainees were more likely to rate their training as representative of reality (P<0.01). Conclusions: Training on virtual reality and computer-enhanced devices had equivalent effects on skills improvement in novices. Despite the perception that haptic feedback is important in laparoscopic simulation training, its absence in the virtual reality device did not impede acquisition of skill. PMID:18765042

Workload Characterization of CFD Applications Using Partial Differential Equation Solvers

NASA Technical Reports Server (NTRS)

Waheed, Abdul; Yan, Jerry; Saini, Subhash (Technical Monitor)

1998-01-01

Workload characterization is used for modeling and evaluating of computing systems at different levels of detail. We present workload characterization for a class of Computational Fluid Dynamics (CFD) applications that solve Partial Differential Equations (PDEs). This workload characterization focuses on three high performance computing platforms: SGI Origin2000, EBM SP-2, a cluster of Intel Pentium Pro bases PCs. We execute extensive measurement-based experiments on these platforms to gather statistics of system resource usage, which results in workload characterization. Our workload characterization approach yields a coarse-grain resource utilization behavior that is being applied for performance modeling and evaluation of distributed high performance metacomputing systems. In addition, this study enhances our understanding of interactions between PDE solver workloads and high performance computing platforms and is useful for tuning these applications.

MO-E-217A-01: Contrast-Enhanced Spectral Mammography - Physical Aspects and QA.

PubMed

Yaffe, M; Hill, M

2012-06-01

To describe the current state of dual energy contrast-enhanced digital mammography, to discuss those aspects of its operation that require evaluation or monitoring and to propose elements of a program for quality assurance of such systems. The principles of dual-energy contrast imaging will be discussed and tools and techniques for assessment of performance will be described. Many of the elements affecting image quality and dose performance in digital mammography (eg noise, system linearity, consistency of x-ray output and detector performance, artifacts) remain important. In addition, the ability to register images can influence the resultant image quality. The maintenance of breast compression thickness during the imaging procedure and calibration of the system to allow quantification of iodine in the breast represent new challenges to quality assurance. CESM provides a means of acquiring new information regarding tumor angiogenesis and may reveal some cancers that will not be detectable on digital mammography. It may also better demonstrate the extent of disease. The medical physicist must understand the dependence of image quality on physical factors. Implementation of a relevant QA program will be required if the promise of this new modality is to be delivered. © 2012 American Association of Physicists in Medicine.

Using Clickers to Improve Student Engagement and Performance in an Introductory Biochemistry Class

ERIC Educational Resources Information Center

Addison, Stephen; Wright, Adrienne; Milner, Rachel

2009-01-01

As part of ongoing efforts to enhance teaching practices in a large-class introductory biochemistry course, we have recently tested the effects of using a student response system (clickers) on student exam performances and engagement with the course material. We found no measurable difference in class mean composite examination score for students…

Hierarchical Discrete Event Supervisory Control of Aircraft Propulsion Systems

NASA Technical Reports Server (NTRS)

Yasar, Murat; Tolani, Devendra; Ray, Asok; Shah, Neerav; Litt, Jonathan S.

2004-01-01

This paper presents a hierarchical application of Discrete Event Supervisory (DES) control theory for intelligent decision and control of a twin-engine aircraft propulsion system. A dual layer hierarchical DES controller is designed to supervise and coordinate the operation of two engines of the propulsion system. The two engines are individually controlled to achieve enhanced performance and reliability, necessary for fulfilling the mission objectives. Each engine is operated under a continuously varying control system that maintains the specified performance and a local discrete-event supervisor for condition monitoring and life extending control. A global upper level DES controller is designed for load balancing and overall health management of the propulsion system.

High-performance sub-terahertz transmission imaging system for food inspection

PubMed Central

Ok, Gyeongsik; Park, Kisang; Chun, Hyang Sook; Chang, Hyun-Joo; Lee, Nari; Choi, Sung-Wook

2015-01-01

Unlike X-ray systems, a terahertz imaging system can distinguish low-density materials in a food matrix. For applying this technique to food inspection, imaging resolution and acquisition speed ought to be simultaneously enhanced. Therefore, we have developed the first continuous-wave sub-terahertz transmission imaging system with a polygonal mirror. Using an f-theta lens and a polygonal mirror, beam scanning is performed over a range of 150 mm. For obtaining transmission images, the line-beam is incorporated with sample translation. The imaging system demonstrates that a pattern with 2.83 mm line-width at 210 GHz can be identified with a scanning speed of 80 mm/s. PMID:26137392

Communication and control in an integrated manufacturing system

NASA Technical Reports Server (NTRS)

Shin, Kang G.; Throne, Robert D.; Muthuswamy, Yogesh K.

1987-01-01

Typically, components in a manufacturing system are all centrally controlled. Due to possible communication bottlenecking, unreliability, and inflexibility caused by using a centralized controller, a new concept of system integration called an Integrated Multi-Robot System (IMRS) was developed. The IMRS can be viewed as a distributed real time system. Some of the current research issues being examined to extend the framework of the IMRS to meet its performance goals are presented. These issues include the use of communication coprocessors to enhance performance, the distribution of tasks and the methods of providing fault tolerance in the IMRS. An application example of real time collision detection, as it relates to the IMRS concept, is also presented and discussed.

Performance measures for arterial traffic signal systems.

DOT National Transportation Integrated Search

2009-05-01

This project was conducted to investigate new concepts, new tools and emerging technologies directed at enhancing traffic operations and safety on signalized urban arterials that operate under saturated conditions. McFarland Boulevard, a six-lane urb...

Spinoff 2011

NASA Technical Reports Server (NTRS)

2012-01-01

Topics include: Bioreactors Drive Advances in Tissue Engineering; Tooling Techniques Enhance Medical Imaging; Ventilator Technologies Sustain Critically Injured Patients; Protein Innovations Advance Drug Treatments, Skin Care; Mass Analyzers Facilitate Research on Addiction; Frameworks Coordinate Scientific Data Management; Cameras Improve Navigation for Pilots, Drivers; Integrated Design Tools Reduce Risk, Cost; Advisory Systems Save Time, Fuel for Airlines; Modeling Programs Increase Aircraft Design Safety; Fly-by-Wire Systems Enable Safer, More Efficient Flight; Modified Fittings Enhance Industrial Safety; Simulation Tools Model Icing for Aircraft Design; Information Systems Coordinate Emergency Management; Imaging Systems Provide Maps for U.S. Soldiers; High-Pressure Systems Suppress Fires in Seconds; Alloy-Enhanced Fans Maintain Fresh Air in Tunnels; Control Algorithms Charge Batteries Faster; Software Programs Derive Measurements from Photographs; Retrofits Convert Gas Vehicles into Hybrids; NASA Missions Inspire Online Video Games; Monitors Track Vital Signs for Fitness and Safety; Thermal Components Boost Performance of HVAC Systems; World Wind Tools Reveal Environmental Change; Analyzers Measure Greenhouse Gasses, Airborne Pollutants; Remediation Technologies Eliminate Contaminants; Receivers Gather Data for Climate, Weather Prediction; Coating Processes Boost Performance of Solar Cells; Analyzers Provide Water Security in Space and on Earth; Catalyst Substrates Remove Contaminants, Produce Fuel; Rocket Engine Innovations Advance Clean Energy; Technologies Render Views of Earth for Virtual Navigation; Content Platforms Meet Data Storage, Retrieval Needs; Tools Ensure Reliability of Critical Software; Electronic Handbooks Simplify Process Management; Software Innovations Speed Scientific Computing; Controller Chips Preserve Microprocessor Function; Nanotube Production Devices Expand Research Capabilities; Custom Machines Advance Composite Manufacturing; Polyimide Foams Offer Superior Insulation; Beam Steering Devices Reduce Payload Weight; Models Support Energy-Saving Microwave Technologies; Materials Advance Chemical Propulsion Technology; and High-Temperature Coatings Offer Energy Savings.

Interacting with target tracking algorithms in a gaze-enhanced motion video analysis system

NASA Astrophysics Data System (ADS)

Hild, Jutta; Krüger, Wolfgang; Heinze, Norbert; Peinsipp-Byma, Elisabeth; Beyerer, Jürgen

2016-05-01

Motion video analysis is a challenging task, particularly if real-time analysis is required. It is therefore an important issue how to provide suitable assistance for the human operator. Given that the use of customized video analysis systems is more and more established, one supporting measure is to provide system functions which perform subtasks of the analysis. Recent progress in the development of automated image exploitation algorithms allow, e.g., real-time moving target tracking. Another supporting measure is to provide a user interface which strives to reduce the perceptual, cognitive and motor load of the human operator for example by incorporating the operator's visual focus of attention. A gaze-enhanced user interface is able to help here. This work extends prior work on automated target recognition, segmentation, and tracking algorithms as well as about the benefits of a gaze-enhanced user interface for interaction with moving targets. We also propose a prototypical system design aiming to combine both the qualities of the human observer's perception and the automated algorithms in order to improve the overall performance of a real-time video analysis system. In this contribution, we address two novel issues analyzing gaze-based interaction with target tracking algorithms. The first issue extends the gaze-based triggering of a target tracking process, e.g., investigating how to best relaunch in the case of track loss. The second issue addresses the initialization of tracking algorithms without motion segmentation where the operator has to provide the system with the object's image region in order to start the tracking algorithm.

Controlled motion in an elastic world. Research project: Manipulation strategies for massive space payloads

NASA Technical Reports Server (NTRS)

Book, Wayne J.

1992-01-01

The flexibility of the drives and structures of controlled motion systems are presented as an obstacle to be overcome in the design of high performance motion systems, particularly manipulator arms. The task and the measure of performance to be applied determine the technology appropriate to overcome this obstacle. Included in the technologies proposed are control algorithms (feedback and feed forward), passive damping enhancement, operational strategies, and structural design. Modeling of the distributed, nonlinear system is difficult, and alternative approaches are discussed. The author presents personal perspectives on the history, status, and future directions in this area.

Creating and indexing teaching files from free-text patient reports.

PubMed Central

Johnson, D. B.; Chu, W. W.; Dionisio, J. D.; Taira, R. K.; Kangarloo, H.

1999-01-01

Teaching files based on real patient data can enhance the education of students, staff and other colleagues. Although information retrieval system can index free-text documents using keywords, these systems do not work well where content bearing terms (e.g., anatomy descriptions) frequently appears. This paper describes a system that uses multi-word indexing terms to provide access to free-text patient reports. The utilization of multi-word indexing allows better modeling of the content of medical reports, thus improving retrieval performance. The method used to select indexing terms as well as early evaluation of retrieval performance is discussed. PMID:10566473

Enhanced performance of the Westinghouse Series 1000 Mobile Satellite Telephone System

NASA Technical Reports Server (NTRS)

Martinson, Richard E.

1995-01-01

The Westinghouse Series 1000 Mobile Satellite Telephone System is designed for land mobile, maritime, and fixed site land applications. The product currently operates on the Optus Mobilesat system in Australia and will operate on American Mobile Satellite Corporation's (AMSC) Skycell service in the U.S. and TMI Communications' (TMIC) MSAT service in Canada. The architecture allows the same transceiver electronics to be used for diverse mobile applications. Advanced antenna designs have made land mobile satellite communications a reality. This paper details the unique high performance product and its configuration for the vehicle mounted land mobile application.

Determination of washout performance of various monochrome displays under simulated flight ambient and solar lighting conditions

NASA Technical Reports Server (NTRS)

Batson, Vernon M.; Robertson, James B.; Parrish, Russell V.

1990-01-01

The aircraft cockpit ambient lighting simulation system (ACALSS) has been developed to study display readability and associated pilot/vehicle performance effects in a part-task simulator cockpit. In the study reported here, the ACALSS was used to determine the illumination levels at which subjects lose the ability to maintain aircraft states when using three display technologies as display media for primary flight displays: a standard monochrome EL (electroluminescent) flat-panel, a laboratory-class monochrome CRT, and an enhanced-brightness EL flat-panel. The multivariate statistical technique of modified profile analysis was used to test for performance differences between display devices as functions of illumination levels. The standard monochrome EL flat-panel display began to washout after the 2500 foot-candle level of illumination. The monochrome CRT began to washout after the 5500 foot-candle level of illumination. No performance decrements by increased illumination up to the 12,000 foot-candle level were found for the enhanced-brightness EL flat-panel display. What was not anticipated was that half the subjects would subjectively prefer the CRT over the enhanced-brightness EL, even though their performance errors would have indicated the opposite.

Making Health System Performance Measurement Useful to Policy Makers: Aligning Strategies, Measurement and Local Health System Accountability in Ontario

PubMed Central

Veillard, Jeremy; Huynh, Tai; Ardal, Sten; Kadandale, Sowmya; Klazinga, Niek S.; Brown, Adalsteinn D.

2010-01-01

This study examined the experience of the Ontario Ministry of Health and Long-Term Care in enhancing its stewardship and performance management role by developing a health system strategy map and a strategy-based scorecard through a process of policy reviews and expert consultations, and linking them to accountability agreements. An evaluation of the implementation and of the effects of the policy intervention has been carried out through direct policy observation over three years, document analysis, interviews with decision-makers and systematic discussion of findings with other authors and external reviewers. Cascading strategies at health and local health system levels were identified, and a core set of health system and local health system performance indicators was selected and incorporated into accountability agreements with the Local Health Integration Networks. despite the persistence of such challenges as measurement limitations and lack of systematic linkage to decision-making processes, these activities helped to strengthen substantially the ministry's performance management function. PMID:21286268

Performance of a system of reservoirs on futuristic front

NASA Astrophysics Data System (ADS)

Saha, Satabdi; Roy, Debasri; Mazumdar, Asis

2017-10-01

Application of simulation model HEC-5 to analyze the performance of the DVC Reservoir System (a multipurpose system with a network of five reservoirs and one barrage) on the river Damodar in Eastern India in meeting projected future demand as well as controlling flood for synthetically generated future scenario is addressed here with a view to develop an appropriate strategy for its operation. Thomas-Fiering model (based on Markov autoregressive model) has been adopted for generation of synthetic scenario (monthly streamflow series) and subsequently downscaling of modeled monthly streamflow to daily values was carried out. The performance of the system (analysed on seasonal basis) in terms of `Performance Indices' (viz., both quantity based reliability and time based reliability, mean daily deficit, average failure period, resilience and maximum vulnerability indices) for the projected scenario with enhanced demand turned out to be poor compared to that for historical scenario. However, judicious adoption of resource enhancement (marginal reallocation of reservoir storage capacity) and demand management strategy (curtailment of projected high water requirements and trading off between demands) was found to be a viable option for improvement of the performance of the reservoir system appreciably [improvement being (1-51 %), (2-35 %), (16-96 %), (25-50 %), (8-36 %) and (12-30 %) for the indices viz., quantity based reliability, time based reliability, mean daily deficit, average failure period, resilience and maximum vulnerability, respectively] compared to that with normal storage and projected demand. Again, 100 % reliability for flood control for current as well as future synthetically generated scenarios was noted. The results from the study would assist concerned authority in successful operation of reservoirs in the context of growing demand and dwindling resource.

Performance of the CELSS Antarctic Analog Project (CAAP) Crop Production System

NASA Technical Reports Server (NTRS)

Bubenheim, David L.; Flynn, Michael T.; Bates, Maynard; Schlick, Greg; Kliss, Mark (Technical Monitor)

1998-01-01

Regenerative life support systems potentially offer a level of self-sufficiency and a concomitant decrease in logistics and associated costs in support of space exploration and habitation missions. Current state-of-the-art in plant based, regenerative life support requires resources in excess of resource allocations proposed for candidate mission scenarios. Feasibility thresholds have been identified for candidate exploration missions. The goal of this paper is to review recent advances in performance achieved in the CELSS Antarctic Analog Project (CAAP) in light of likely resource constraints. A prototype CAAP crop production chamber has been constructed and operated at the Ames Research Center. The chamber includes a number of unique hardware and software components focused on attempts to increase production efficiency, increase energy efficiency, and control the flow of energy and mass through the system to achieve enhanced performance efficiency. Both single crop, batch production, and continuous cultivation of mixed crops Product ion scenarios have been completed. The crop productivity as well as engineering performance of the chamber will be described. For each scenario, energy required and partitioned for lighting, cooling, pumps, fans, etc. is quantified. Crop production and the resulting lighting efficiency and energy conversion efficiencies are presented. In the mixed-crop scenario, with up to 25 different crops under cultivation, 17 sq m of crop area provided a mean of 515 g edible biomass per day (83% of the approximately 620 g required for one person). Lighting efficiency (moles on photons kWh-1) approached 4 and the conversion efficiency of light energy to biomass was greatly enhanced compared with conventional growing systems. Engineering and biological performance achieved place plant-based life support systems at the threshold of feasibility.

Continued Development of Expert System Tools for NPSS Engine Diagnostics

NASA Technical Reports Server (NTRS)

Lewandowski, Henry

1996-01-01

The objectives of this grant were to work with previously developed NPSS (Numerical Propulsion System Simulation) tools and enhance their functionality; explore similar AI systems; and work with the High Performance Computing Communication (HPCC) K-12 program. Activities for this reporting period are briefly summarized and a paper addressing the implementation, monitoring and zooming in a distributed jet engine simulation is included as an attachment.

Infrared sensors and systems for enhanced vision/autonomous landing applications

NASA Technical Reports Server (NTRS)

Kerr, J. Richard

1993-01-01

There exists a large body of data spanning more than two decades, regarding the ability of infrared imagers to 'see' through fog, i.e., in Category III weather conditions. Much of this data is anecdotal, highly specialized, and/or proprietary. In order to determine the efficacy and cost effectiveness of these sensors under a variety of climatic/weather conditions, there is a need for systematic data spanning a significant range of slant-path scenarios. These data should include simultaneous video recordings at visible, midwave (3-5 microns), and longwave (8-12 microns) wavelengths, with airborne weather pods that include the capability of determining the fog droplet size distributions. Existing data tend to show that infrared is more effective than would be expected from analysis and modeling. It is particularly more effective for inland (radiation) fog as compared to coastal (advection) fog, although both of these archetypes are oversimplifications. In addition, as would be expected from droplet size vs wavelength considerations, longwave outperforms midwave, in many cases by very substantial margins. Longwave also benefits from the higher level of available thermal energy at ambient temperatures. The principal attraction of midwave sensors is that staring focal plane technology is available at attractive cost-performance levels. However, longwave technology such as that developed at FLIR Systems, Inc. (FSI), has achieved high performance in small, economical, reliable imagers utilizing serial-parallel scanning techniques. In addition, FSI has developed dual-waveband systems particularly suited for enhanced vision flight testing. These systems include a substantial, embedded processing capability which can perform video-rate image enhancement and multisensor fusion. This is achieved with proprietary algorithms and includes such operations as real-time histograms, convolutions, and fast Fourier transforms.

Imaging Performance of a Handheld Ultrasound System With Real-Time Computer-Aided Detection of Lumbar Spine Anatomy: A Feasibility Study.

PubMed

Tiouririne, Mohamed; Dixon, Adam J; Mauldin, F William; Scalzo, David; Krishnaraj, Arun

2017-08-01

The aim of this study was to evaluate the imaging performance of a handheld ultrasound system and the accuracy of an automated lumbar spine computer-aided detection (CAD) algorithm in the spines of human subjects. This study was approved by the institutional review board of the University of Virginia. The authors designed a handheld ultrasound system with enhanced bone image quality and fully automated CAD of lumbar spine anatomy. The imaging performance was evaluated by imaging the lumbar spines of 68 volunteers with body mass index between 18.5 and 48 kg/m. The accuracy, sensitivity, and specificity of the lumbar spine CAD algorithm were assessed by comparing the algorithm's results to ground-truth segmentations of neuraxial anatomy provided by radiologists. The lumbar spine CAD algorithm detected the epidural space with a sensitivity of 94.2% (95% confidence interval [CI], 85.1%-98.1%) and a specificity of 85.5% (95% CI, 81.7%-88.6%) and measured its depth with an error of approximately ±0.5 cm compared with measurements obtained manually from the 2-dimensional ultrasound images. The spine midline was detected with a sensitivity of 93.9% (95% CI, 85.8%-97.7%) and specificity of 91.3% (95% CI, 83.6%-96.9%), and its lateral position within the ultrasound image was measured with an error of approximately ±0.3 cm. The bone enhancement imaging mode produced images with 5.1- to 10-fold enhanced bone contrast when compared with a comparable handheld ultrasound imaging system. The results of this study demonstrate the feasibility of CAD for assisting with real-time interpretation of ultrasound images of the lumbar spine at the bedside.

Differentiation of rodent behavioral phenotypes and methylphenidate action in sustained and flexible attention tasks.

PubMed

Chu, Richard; Shumsky, Jed; Waterhouse, Barry D

2016-06-15

Methyphenidate (MPH) is the primary drug treatment of choice for ADHD. It is also frequently used off-label as a cognitive enhancer by otherwise healthy individuals from all age groups and walks of life. Military personnel, students, and health professionals use MPH illicitly to increase attention and improve workplace performance over extended periods of work activity. Despite the frequency of its use, the efficacy of MPH to enhance cognitive function across individuals and in a variety of circumstances is not well characterized. We sought to better understand MPH׳s cognitive enhancing properties in two different rodent models of attention. We found that MPH could enhance performance in a sustained attention task, but that its effects in this test were subject dependent. More specifically, MPH increased attention in low baseline performing rats but had little to no effect on high performing rats. MPH exerted a similar subject specific effect in a test of flexible attention, i.e. the attention set shifting task. In this test MPH increased behavioral flexibility in animals with poor flexibility but impaired performance in more flexible animals. Overall, our results indicate that the effects of MPH are subject-specific and depend on the baseline level of performance. Furthermore, good performance in in the sustained attention task was correlated with good performance in the flexible attention task; i.e. animals with better vigilance exhibited greater behavioral flexibility. The findings are discussed in terms of potential neurobiological substrates, in particular noradrenergic mechanisms, that might underlie subject specific performance and subject specific responses to MPH. This article is part of a Special Issue entitled SI: Noradrenergic System. Copyright © 2016 Elsevier B.V. All rights reserved.

Fix These First: How the World's Leading Companies Point the Way Toward High Reliability in the Military Health System.

PubMed

Beauvais, Brad; Richter, Jason; Brezinski, Paul

The 2014 Military Health System Review calls for healthcare system leaders to implement effective strategies used by other high-performing organizations. The authors state, " the [military health system] MHS can create an optimal healthcare environment that focuses on continuous quality improvement where every patient receives safe, high-quality care at all times" (Military Health System, 2014, p. 1). Although aspirational, the document does not specify how a highly reliable health system is developed or what systemic factors are necessary to sustain highly reliable performance. Our work seeks to address this gap and provide guidance to MHS leaders regarding how high-performing organizations develop exceptional levels of performance.The authors' expectation is that military medicine will draw on these lessons to enhance leadership, develop exceptional organizational cultures, onboard and engage employees, build customer loyalty, and improve quality of care. Leaders from other segments of the healthcare field likely will find this study valuable given the size of the military healthcare system (9.6 million beneficiaries), the United States' steady progression toward population-based health, and the increasing need for highly reliable systems and performance.

Technological Advances in Interventions to Enhance Post-Stroke Gait

PubMed Central

Sheffler, Lynne R.; Chae, John

2012-01-01

Synopsis This article provides a comprehensive review of specific rehabilitation interventions used to enhance hemiparetic gait following stroke. Neurologic rehabilitation interventions may be either therapeutic resulting in enhanced motor recovery or compensatory whereby assistance or substitution for neurological deficits results in improved functional performance. Included in this review are lower extremity functional electrical stimulation (FES), body-weight supported treadmill training (BWSTT), and lower extremity robotic-assisted gait training. These post-stroke gait training therapies are predicated on activity-dependent neuroplasticity which is the concept that cortical reorganization following central nervous system injury may be induced by repetitive, skilled, and cognitively engaging active movement. All three interventions have been trialed extensively in both research and clinical settings to demonstrate a positive effect on various gait parameters and measures of walking performance. However, more evidence is necessary to determine if specific technology-enhanced gait training methods are superior to conventional gait training methods. This review provides an overview of evidence-based research which supports the efficacy of these three interventions to improve gait, as well as provide perspective on future developments to enhance post-stroke gait in neurologic rehabilitation. PMID:23598265

Implementation of an Embedded Web Server Application for Wireless Control of Brain Computer Interface Based Home Environments.

PubMed

Aydın, Eda Akman; Bay, Ömer Faruk; Güler, İnan

2016-01-01

Brain Computer Interface (BCI) based environment control systems could facilitate life of people with neuromuscular diseases, reduces dependence on their caregivers, and improves their quality of life. As well as easy usage, low-cost, and robust system performance, mobility is an important functionality expected from a practical BCI system in real life. In this study, in order to enhance users' mobility, we propose internet based wireless communication between BCI system and home environment. We designed and implemented a prototype of an embedded low-cost, low power, easy to use web server which is employed in internet based wireless control of a BCI based home environment. The embedded web server provides remote access to the environmental control module through BCI and web interfaces. While the proposed system offers to BCI users enhanced mobility, it also provides remote control of the home environment by caregivers as well as the individuals in initial stages of neuromuscular disease. The input of BCI system is P300 potentials. We used Region Based Paradigm (RBP) as stimulus interface. Performance of the BCI system is evaluated on data recorded from 8 non-disabled subjects. The experimental results indicate that the proposed web server enables internet based wireless control of electrical home appliances successfully through BCIs.

Unravelling networks in local public health policymaking in three European countries - a systems analysis.

PubMed

Spitters, Hilde P E M; Lau, Cathrine J; Sandu, Petru; Quanjel, Marcel; Dulf, Diana; Glümer, Charlotte; van Oers, Hans A M; van de Goor, Ien A M

2017-02-03

Facilitating and enhancing interaction between stakeholders involved in the policymaking process to stimulate collaboration and use of evidence, is important to foster the development of effective Health Enhancing Physical Activity (HEPA) policies. Performing an analysis of real-world policymaking processes will help reveal the complexity of a network of stakeholders. Therefore, the main objectives were to unravel the stakeholder network in the policy process by conducting three systems analyses, and to increase insight into the similarities and differences in the policy processes of these European country cases. A systems analysis of the local HEPA policymaking process was performed in three European countries involved in the 'REsearch into POlicy to enhance Physical Activity' (REPOPA) project, resulting in three schematic models showing the main stakeholders and their relationships. The models were used to compare the systems, focusing on implications with respect to collaboration and use of evidence in local HEPA policymaking. Policy documents and relevant webpages were examined and main stakeholders were interviewed. The systems analysis in each country identified the main stakeholders involved and their position and relations in the policymaking process. The Netherlands and Denmark were the most similar and both differed most from Romania, especially at the level of accountability of the local public authorities for local HEPA policymaking. The categories of driving forces underlying the relations between stakeholders were formal relations, informal interaction and knowledge exchange. A systems analysis providing detailed descriptions of positions and relations in the stakeholder network in local level HEPA policymaking is rather unique in this area. The analyses are useful when a need arises for increased interaction, collaboration and use of knowledge between stakeholders in the local HEPA network, as they provide an overview of the stakeholders involved and their mutual relations. This information can be an important starting point to enhance the uptake of evidence and build more effective public health policies.

Pilot-in-the-Loop Evaluation of a Yaw Rate to Throttle Feedback Control with Enhanced Engine Response

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.; Guo, Ten-Huei; Sowers, T. Shane; Chicatelli, Amy K.; Fulton, Christopher E.; May, Ryan D.; Owen, A. Karl

2012-01-01

This paper describes the implementation and evaluation of a yaw rate to throttle feedback system designed to replace a damaged rudder. It can act as a Dutch roll damper and as a means to facilitate pilot input for crosswind landings. Enhanced propulsion control modes were implemented to increase responsiveness and thrust level of the engine, which impact flight dynamics and performance. Piloted evaluations were performed to determine the capability of the engines to substitute for the rudder function under emergency conditions. The results showed that this type of implementation is beneficial, but the engines' capability to replace the rudder is limited.

Laser development for optimal helicopter obstacle warning system LADAR performance

NASA Astrophysics Data System (ADS)

Yaniv, A.; Krupkin, V.; Abitbol, A.; Stern, J.; Lurie, E.; German, A.; Solomonovich, S.; Lubashitz, B.; Harel, Y.; Engart, S.; Shimoni, Y.; Hezy, S.; Biltz, S.; Kaminetsky, E.; Goldberg, A.; Chocron, J.; Zuntz, N.; Zajdman, A.

2005-04-01

Low lying obstacles present immediate danger to both military and civilian helicopters performing low-altitude flight missions. A LADAR obstacle detection system is the natural solution for enhancing helicopter safety and improving the pilot situation awareness. Elop is currently developing an advanced Surveillance and Warning Obstacle Ranging and Display (SWORD) system for the Israeli Air Force. Several key factors and new concepts have contributed to system optimization. These include an adaptive FOV, data memorization, autonomous obstacle detection and warning algorithms and the use of an agile laser transmitter. In the present work we describe the laser design and performance and discuss some of the experimental results. Our eye-safe laser is characterized by its pulse energy, repetition rate and pulse length agility. By dynamically controlling these parameters, we are able to locally optimize the system"s obstacle detection range and scan density in accordance with the helicopter instantaneous maneuver.

Performance evaluation of FSO system using wavelength and time diversity over malaga turbulence channel with pointing errors

NASA Astrophysics Data System (ADS)

Balaji, K. A.; Prabu, K.

2018-03-01

There is an immense demand for high bandwidth and high data rate systems, which is fulfilled by wireless optical communication or free space optics (FSO). Hence FSO gained a pivotal role in research which has a added advantage of both cost-effective and licence free huge bandwidth. Unfortunately the optical signal in free space suffers from irradiance and phase fluctuations due to atmospheric turbulence and pointing errors which deteriorates the signal and degrades the performance of communication system over longer distance which is undesirable. In this paper, we have considered polarization shift keying (POLSK) system applied with wavelength and time diversity technique over Malaga(M)distribution to mitigate turbulence induced fading. We derived closed form mathematical expressions for estimating the systems outage probability and average bit error rate (BER). Ultimately from the results we can infer that wavelength and time diversity schemes enhances these systems performance.

Development of a solar-powered residential air conditioner: System optimization preliminary specification

NASA Technical Reports Server (NTRS)

Rousseau, J.; Hwang, K. C.

1975-01-01

Investigations aimed at the optimization of a baseline Rankine cycle solar powered air conditioner and the development of a preliminary system specification were conducted. Efforts encompassed the following: (1) investigations of the use of recuperators/regenerators to enhance the performance of the baseline system, (2) development of an off-design computer program for system performance prediction, (3) optimization of the turbocompressor design to cover a broad range of conditions and permit operation at low heat source water temperatures, (4) generation of parametric data describing system performance (COP and capacity), (5) development and evaluation of candidate system augmentation concepts and selection of the optimum approach, (6) generation of auxiliary power requirement data, (7) development of a complete solar collector-thermal storage-air conditioner computer program, (8) evaluation of the baseline Rankine air conditioner over a five day period simulating the NASA solar house operation, and (9) evaluation of the air conditioner as a heat pump.

Receiver operating characteristic for a spectrogram correlator-based humpback whale detector-classifier.

PubMed

Abbot, Ted A; Premus, Vincent E; Abbot, Philip A; Mayer, Owen A

2012-09-01

This paper presents recent experimental results and a discussion of system enhancements made to the real-time autonomous humpback whale detector-classifier algorithm first presented by Abbot et al. [J. Acoust. Soc. Am. 127, 2894-2903 (2010)]. In February 2010, a second-generation system was deployed in an experiment conducted off of leeward Kauai during which 26 h of humpback vocalizations were recorded via sonobuoy and processed in real time. These data have been analyzed along with 40 h of humpbacks-absent data collected from the same location during July-August 2009. The extensive whales-absent data set in particular has enabled the quantification of system false alarm rates and the measurement of receiver operating characteristic curves. The performance impact of three enhancements incorporated into the second-generation system are discussed, including (1) a method to eliminate redundancy in the kernel library, (2) increased use of contextual analysis, and (3) the augmentation of the training data with more recent humpback vocalizations. It will be shown that the performance of the real-time system was improved to yield a probability of correct classification of 0.93 and a probability of false alarm of 0.004 over the 66 h of independent test data.

Thiolated polycarbophil/glutathione: defining its potential as a permeation enhancer for oral drug administration in comparison to sodium caprate.

PubMed

Perera, Glen; Barthelmes, Jan; Vetter, Anja; Krieg, Christof; Uhlschmied, Cindy; Bonn, Günther K; Bernkop-Schnürch, Andreas

2011-08-01

Thiolated polyacrylates were shown to be permeation enhancers with notable potential. The aim of this study was to evaluate the permeation enhancing properties of a thiolated polycarbophil/glutathione (PCP-Cys/GSH) system for oral drug application in comparison to a well-established permeation enhancer, namely sodium caprate. In vitro permeation studies were conducted in Ussing-type chambers with sodium fluoresceine (NaFlu) and fluoresceine isothiocyanate labeled dextran (molecular mass 4 kDa; FD4) as model compounds. Bioavailability studies were carried out in Sprague Dawley rats with various formulations. Moreover, cytotoxic effects of both permeation enhancers were compared. Permeation enhancement ratios of 1% sodium caprate were found to be 3.0 (FD4) and 2.3 (NaFlu), whereas 1% PCP-Cys/0.5% GSH displayed enhancement ratios of 2.4 and 2.2. Both excipients performed at a similar level in vivo. Sodium caprate solutions increased oral bioavailability 2.2-fold (FD4) and 2.3-fold (NaFlu), while PCP-Cys hydrogels led to a 3.2-fold and 2.2-fold enhancement. Cell viability experiments revealed a significantly higher tolerance of Caco-2 cells towards 0.5% PCP-Cys (81% survival) compared to 0.5% sodium caprate (5%). As PCP-Cys is not absorbed from mucosal membranes due to its comparatively high molecular mass, systemic side-effects can be excluded. In conclusion, both systems displayed a similar potency for permeation enhancement of hydrophilic compounds. However, PCP-Cys seems to be less harmful to cultured cells.