The validity of ACT-PEP test scores for predicting academic performance of registered nurses in BSN programs.

PubMed

Yang, J C; Noble, J

1990-01-01

This study investigated the validity of three American College Testing-Proficiency Examination Program (ACT-PEP) tests (Maternal and Child Nursing, Psychiatric/Mental Health Nursing, Adult Nursing) for predicting the academic performance of registered nurses (RNs) enrolled in bachelor's degree BSN programs nationwide. This study also examined RN students' performance on the ACT-PEP tests by their demographic characteristics: student's age, sex, race, student status (full- or part-time), and employment status (full- or part-time). The total sample for the three tests comprised 2,600 students from eight institutions nationwide. The median correlation coefficients between the three ACT-PEP tests and the semester grade point averages ranged from .36 to .56. Median correlation coefficients increased over time, supporting the stability of ACT-PEP test scores for predicting academic performance over time. The relative importance of selected independent variables for predicting academic performance was also examined; the most important variable for predicting academic performance was typically the ACT-PEP test score. Across the institutions, student demographic characteristics did not contribute significantly to explaining academic performance, over and above ACT-PEP scores.

Using Differential Item Functioning Procedures to Explore Sources of Item Difficulty and Group Performance Characteristics.

ERIC Educational Resources Information Center

Scheuneman, Janice Dowd; Gerritz, Kalle

1990-01-01

Differential item functioning (DIF) methodology for revealing sources of item difficulty and performance characteristics of different groups was explored. A total of 150 Scholastic Aptitude Test items and 132 Graduate Record Examination general test items were analyzed. DIF was evaluated for males and females and Blacks and Whites. (SLD)

Parametric analysis of ATM solar array.

NASA Technical Reports Server (NTRS)

Singh, B. K.; Adkisson, W. B.

1973-01-01

The paper discusses the methods used for the calculation of ATM solar array performance characteristics and provides the parametric analysis of solar panels used in SKYLAB. To predict the solar array performance under conditions other than test conditions, a mathematical model has been developed. Four computer programs have been used to convert the solar simulator test data to the parametric curves. The first performs module summations, the second determines average solar cell characteristics which will cause a mathematical model to generate a curve matching the test data, the third is a polynomial fit program which determines the polynomial equations for the solar cell characteristics versus temperature, and the fourth program uses the polynomial coefficients generated by the polynomial curve fit program to generate the parametric data.

42 CFR 493.1253 - Standard: Establishment and verification of performance specifications.

Code of Federal Regulations, 2014 CFR

2014-10-01

... establish performance specifications for any test system used by the laboratory before April 24, 2003. (b)(1... approved test system must do the following before reporting patient test results: (i) Demonstrate that it... following performance characteristics: (A) Accuracy. (B) Precision. (C) Reportable range of test results for...

42 CFR 493.1253 - Standard: Establishment and verification of performance specifications.

Code of Federal Regulations, 2013 CFR

2013-10-01

... establish performance specifications for any test system used by the laboratory before April 24, 2003. (b)(1... approved test system must do the following before reporting patient test results: (i) Demonstrate that it... following performance characteristics: (A) Accuracy. (B) Precision. (C) Reportable range of test results for...

42 CFR 493.1253 - Standard: Establishment and verification of performance specifications.

Code of Federal Regulations, 2012 CFR

2012-10-01

... establish performance specifications for any test system used by the laboratory before April 24, 2003. (b)(1... approved test system must do the following before reporting patient test results: (i) Demonstrate that it... following performance characteristics: (A) Accuracy. (B) Precision. (C) Reportable range of test results for...

42 CFR 493.1253 - Standard: Establishment and verification of performance specifications.

Code of Federal Regulations, 2011 CFR

2011-10-01

... establish performance specifications for any test system used by the laboratory before April 24, 2003. (b)(1... approved test system must do the following before reporting patient test results: (i) Demonstrate that it... following performance characteristics: (A) Accuracy. (B) Precision. (C) Reportable range of test results for...

Strapdown gyro test program

NASA Technical Reports Server (NTRS)

Irvine, R. B.; Vanalstine, R.

1977-01-01

The power spectral noise characteristic performance of the Teledyne two-degree-of-freedom dry tuned gimbal gyroscope was determined. Tests were conducted using a current configuration SDG-5 gyro in conjunction with test equipment with minor modification. Long term bias stability tests were conducted as well as some first difference performance tests. The gyro, test equipment, and the tests performed are described. Results are presented.

Task 12 data dump (phase 2) OME integrated thrust chamber test report

NASA Technical Reports Server (NTRS)

Tobin, R. D.; Pauckert, R. P.

1974-01-01

The characteristics and performance of the orbit maneuvering engine for the space shuttle are discussed. Emphasis is placed on the regeneratively cooled thrust chamber of the engine. Tests were conducted to determine engine operating parameters during the start, shutdown, and restart. Characteristics of the integrated thrust chamber and the performance and thermal conditions for blowdown operation without supplementary boundary layer cooling were investigated. The results of the test program are presented.

Small passenger car transmission test; Chevrolet LUV transmission

NASA Technical Reports Server (NTRS)

Bujold, M. P.

1980-01-01

A 1978 Chevrolet LUV manual transmission tested per the applicable portions of a passenger car automatic transmission test code (SAE J65lb) which required drive performance, coast performance, and no load test conditions. Under these test conditions, the transmission attained maximum efficiencies in the upper ninety percent range for both drive performance tests and coast performance tests. The major results of this test (torque, speed, and efficiency curves) are presented. Graphs map the complete performance characteristics for the Chevrolet LUV transmission.

Small passenger car transmission test; Ford C4 transmission

NASA Technical Reports Server (NTRS)

Bujold, M. P.

1980-01-01

A 1979 Ford C4 automatic transmission was tested per a passenger car automatic transmission test code (SAE J651b) which required drive performance, coast performance, and no load test conditions. Under these test conditions, the transmission attained maximum efficiencies in the mid-eighty percent range for both drive performance tests and coast performance tests. The major results of this test (torque, speed, and efficiency curves) are presented. Graphs map the complete performance characteristics for the Ford C4 transmission.

Muscle contractile characteristics: relationship to high-intensity exercise.

PubMed

Morris, Martyn G; Dawes, Helen; Howells, Ken; Scott, Oona M; Cramp, Mary; Izadi, Hooshang

2010-09-01

We investigated the relationship between muscle contractile characteristics, collected using percutaneous electrical stimulation, and high-intensity exercise performance. Seventeen participants performed a muscle performance test for the calculation of rate of torque development (RTD), rate of relaxation (RR(1/2)), rate of fatigue and fatigue resistance. On a second visit the participants completed a Wingate cycle ergometer test with peak power, mean power, fatigue index and fatigue rate calculated. The muscle fatigue index related significantly to the WAnT fatigue index and fatigue rate (p < 0.01). The change in rate of torque development (%DeltaRTD) was also related significantly to the fatigue rate (W/s) during the WAnT. Subjects displaying the greatest reduction in RTD had the greatest fatigue rate during the WAnT and greater fatigue during the electrical stimulation protocol. There were no significant relationships between peak (r 0.36; p > 0.01) or mean power (r -0.11, p > 0.01) with any of the muscle performance measures. These findings demonstrate that muscle contractile characteristics, elicited during standardised in vivo electrical stimulation, relate to performance during a Wingate anaerobic test. They suggest that muscle contraction characteristics play an important role in high-intensity exercise performance and indicate that electrical stimulation protocols can be a useful additional tool to explore muscle contraction characteristics in relation to exercise performance and trainability.

Experimental Aerodynamic Characteristics of a Joined-wing Research Aircraft Configuration

NASA Technical Reports Server (NTRS)

Smith, Stephen C.; Stonum, Ronald K.

1989-01-01

A wind-tunnel test was conducted at Ames Research Center to measure the aerodynamic characteristics of a joined-wing research aircraft (JWRA). This aircraft was designed to utilize the fuselage and engines of the existing NASA AD-1 aircraft. The JWRA was designed to have removable outer wing panels to represent three different configurations with the interwing joint at different fractions of the wing span. A one-sixth-scale wind-tunnel model of all three configurations of the JWRA was tested in the Ames 12-Foot Pressure Wind Tunnel to measure aerodynamic performance, stability, and control characteristics. The results of these tests are presented. Longitudinal and lateral-directional characteristics were measured over an angle of attack range of -7 to 14 deg and over an angle of sideslip range of -5 to +2.5 deg at a Mach number of 0.35 and a Reynolds number of 2.2x10(6)/ft. Various combinations of deflected control surfaces were tested to measure the effectiveness and impact on stability of several control surface arrangements. In addition, the effects on stall and post-stall aerodynamic characteristics from small leading-edge devices called vortilons were measured. The results of these tests indicate that the JWRA had very good aerodynamic performance and acceptable stability and control throughout its flight envelope. The vortilons produced a profound improvement in the stall and post-stall characteristics with no measurable effects on cruise performance.

Testing of optical components to assure performance in a high-average-power environment

NASA Astrophysics Data System (ADS)

Chow, Robert; Taylor, John R.; Eickelberg, William K.; Primdahl, Keith A.

1997-11-01

Evaluation and testing of the optical components used in the atomic vapor laser isotope separation plant is critical for qualification of suppliers, developments of new optical multilayer designs and manufacturing processes, and assurance of performance in the production cycle. The range of specifications requires development of specialized test equipment and methods which are not routine or readily available in industry. Specifications are given on material characteristics such as index homogeneity, subsurface damage left after polishing, microscopic surface defects and contamination, coating absorption, and high average power laser damage. The approach to testing these performance characteristics and assuring the quality throughout the production cycle is described.

Evolution of Quality Assurance for Clinical Immunohistochemistry in the Era of Precision Medicine - Part 2: Immunohistochemistry Test Performance Characteristics.

PubMed

Torlakovic, Emina E; Cheung, Carol C; D'Arrigo, Corrado; Dietel, Manfred; Francis, Glenn D; Gilks, C Blake; Hall, Jacqueline A; Hornick, Jason L; Ibrahim, Merdol; Marchetti, Antonio; Miller, Keith; van Krieken, J Han; Nielsen, Soren; Swanson, Paul E; Vyberg, Mogens; Zhou, Xiaoge; Taylor, Clive R

2017-02-01

All laboratory tests have test performance characteristics (TPCs), whether or not they are explicitly known to the laboratorian or the pathologist. TPCs are thus also an integral characteristic of immunohistochemistry (IHC) tests and other in situ, cell-based molecular assays such as DNA or RNA in situ hybridization or aptamer-based testing. Because of their descriptive, in situ, cell-based nature, IHC tests have a limited repertoire of appropriate TPCs. Although only a few TPCs are relevant to IHC, proper selection of informative TPCs is nonetheless essential for the development of and adherence to appropriate quality assurance measures in the IHC laboratory. This paper describes the TPCs that are relevant to IHC testing and emphasizes the role of TPCs in the validation of IHC tests. This is part 2 of the 4-part series "Evolution of Quality Assurance for Clinical Immunohistochemistry in the Era of Precision Medicine."

Eddy Current Damper for Cryogenic Applications

NASA Astrophysics Data System (ADS)

Starin, Scott; Crosno, Fred

2002-09-01

This presentation considers the following topics: the need for cryogenic energy absorption, high speed damper characteristics, gearbox characteristics, composite assembly characteristics, performance tests, simulation models.

Computerized Adaptive Performance Evaluation.

DTIC Science & Technology

1980-02-01

based on classical psychological test theory, with the result that the obtained measurements ani statements of achievement or performance have... psychological aspects of the achievement testing environment. Results , C Applications of Item Characteristic Curve Models and Adaptive Testing Strategies ICC...of immediate knowledge of results and adaptive testing on ability test performance (Research Report 76-4). Minneapolis: Department of Psychology

Small passenger car transmission test: Mercury Lynx ATX transmission

NASA Technical Reports Server (NTRS)

Bujold, M. P.

1981-01-01

The testing of a Mercury Lynx automatic transmission is reported. The transmission was tested in accordance with a passenger car automatic transmission test code (SAE J65lb) which required drive performance, coast performance, and no load test conditions. Under these conditions, the transmission attained maximum efficiencies in the mid-ninety percent range both for drive performance test and coast performance tests. The torque, speed, and efficiency curves are presented, which provide the complete performance characteristics for the Mercury Lynx automatic transmission.

Genetic parameters for type classification of Nelore cattle on central performance tests at pasture in Brazil.

PubMed

Lima, Paulo Ricardo Martins; Paiva, Samuel Rezende; Cobuci, Jaime Araujo; Braccini Neto, José; Machado, Carlos Henrique Cavallari; McManus, Concepta

2013-10-01

The objective of this study was to characterize Nelore cattle on central performance tests in pasture, ranked by the visual classification method EPMURAS (structure, precocity, muscle, navel, breed, posture, and sexual characteristics), and to estimate genetic and phenotypic correlations between these parameters, including visual as well as production traits (initial and final weight on test, weight gain, and weight corrected for 550 days). The information used in the study was obtained on 21,032 Nelore bulls which were participants in the central performance test at pasture of the Brazilian Association for Zebu Breeders (ABCZ). Heritabilities obtained were from 0.19 to 0.50. Phenotypic correlations were positive from 0.70 to 0.97 between the weight traits, from 0.65 to 0.74 between visual characteristics, and from 0.29 to 0.47 between visual characteristics and weight traits. The genetic correlations were positive ranging from 0.80 to 0.98 between the characteristics of structure, precocity and musculature, from 0.13 to 0.64 between the growth characteristics, and from 0.41 to 0.97 between visual scores and weight gains. Heritability and genetic correlations indicate that the use of visual scores, along with the selection for growth characteristics, can bring positive results in selection of beef cattle for rearing on pasture.

James Webb Space Telescope Deployment Brushless DC Motor Characteristics Analysis

NASA Technical Reports Server (NTRS)

Tran, Ahn N.

2016-01-01

A DC motor's performance is usually characterized by a series of tests, which are conducted by pass/fail criteria. In most cases, these tests are adequate to address the performance characteristics under environmental and loading effects with some uncertainties and decent power/torque margins. However, if the motor performance requirement is very stringent, a better understanding of the motor characteristics is required. The purpose of this paper is to establish a standard way to extract the torque components of the brushless motor and gear box characteristics of a high gear ratio geared motor from the composite geared motor testing and motor parameter measurement. These torque components include motor magnetic detent torque, Coulomb torque, viscous torque, windage torque, and gear tooth sliding torque. The Aerospace Corp bearing torque model and MPB torque models are used to predict the Coulomb torque of the motor rotor bearings and to model the viscous components. Gear tooth sliding friction torque is derived from the dynamo geared motor test data. With these torque data, the geared motor mechanical efficiency can be estimated and provide the overall performance of the geared motor versus several motor operating parameters such as speed, temperature, applied current, and transmitted power.

Relationship between performance test and body composition/physical strength characteristic in sprint canoe and kayak paddlers

PubMed Central

Hamano, Saki; Ochi, Eisuke; Tsuchiya, Yosuke; Muramatsu, Erina; Suzukawa, Kazuhiro; Igawa, Shoji

2015-01-01

Objective Canoe sprint is divided into canoe and kayak. The difference between the two competitions is in physical performance. The aim of the present study was to compare and investigate the relationship between physical characteristics and fitness between the two canoe sprint competitors. Methods Subjects were 11 canoe paddlers (C) and 12 kayak paddlers (K). They underwent anthropometric characteristics, body composition and fitness tests, and 120 s all-out tests using a canoe and kayak ergometer. The unpaired t-test was used to test for significant differences between disciplines, while Pearson’s correlation coefficient was used to examine the association between each measurement item and the performance test. Results The age, height, body mass, body mass index, and total body fat were, C: 20.6±0.9 yr, 172.8±5.2 cm, 70.8±7.8 kg, 23.7±1.9, 14.4%±3.5%; and K: 19.7±1.2 yr, 172.8±5.3 cm, 69.5±7.8 kg, 23.2±2.1, 12.1%±3.6%, respectively. No significant differences were seen in any of the items for physical characteristics or fitness between C and K. A correlation analysis of performance tests and each measurement item revealed a positive correlation with low-speed isokinetic knee extension and flexion strength for C only (extension: r=0.761; flexion: r=0.784; P<0.01). In addition, performance tests were positively correlated with the circumference of arm (upper arm: r=0.876; forearm: r=0.820; P<0.01) and lower limb (thigh: r=0.781; calf: r=0.753; P<0.01) in C and with height (r=0.549, P<0.05), arm span (r=0.639, P<0.05), and leg length (r=0.621, P<0.01) in K. Conclusion We suggest that the factors correlating with the performance test differ depending on the competitions. PMID:26150737

Understanding protocol performance: impact of test performance.

PubMed

Turner, Robert G

2013-01-01

This is the second of two articles that examine the factors that determine protocol performance. The objective of these articles is to provide a general understanding of protocol performance that can be used to estimate performance, establish limits on performance, decide if a protocol is justified, and ultimately select a protocol. The first article was concerned with protocol criterion and test correlation. It demonstrated the advantages and disadvantages of different criterion when all tests had the same performance. It also examined the impact of increasing test correlation on protocol performance and the characteristics of the different criteria. To examine the impact on protocol performance when individual tests in a protocol have different performance. This is evaluated for different criteria and test correlations. The results of the two articles are combined and summarized. A mathematical model is used to calculate protocol performance for different protocol criteria and test correlations when there are small to large variations in the performance of individual tests in the protocol. The performance of the individual tests that make up a protocol has a significant impact on the performance of the protocol. As expected, the better the performance of the individual tests, the better the performance of the protocol. Many of the characteristics of the different criteria are relatively independent of the variation in the performance of the individual tests. However, increasing test variation degrades some criteria advantages and causes a new disadvantage to appear. This negative impact increases as test variation increases and as more tests are added to the protocol. Best protocol performance is obtained when individual tests are uncorrelated and have the same performance. In general, the greater the variation in the performance of tests in the protocol, the more detrimental this variation is to protocol performance. Since this negative impact is increased as more tests are added to the protocol, greater test variation indicates using fewer tests in the protocol. American Academy of Audiology.

Determination of tube-to-tube support interaction characteristics. [PWR

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

Haslinger, K.H.

Tube-to-tube support interaction characteristics were determined on a multi-span tube geometry representative of the hot-leg side of the C-E, System 80 steam generator design. Results will become input for an autoclave type wear test program on steam generator tubes, performed by Kraftwerk Union (KWU). Correlation of test data reported here with similar data obtained from the wear tests will be performed in an attempt to make predictions about the long-term fretting behavior of steam generator tubes.

Individual Characteristics and Unit Performance: A Review of Research and Methods

DTIC Science & Technology

1985-02-01

behavioral segments, improves performance. Simu- lation exercises , especially those employing new high-technology devices, provide surrogate...high-technology training simulation exercise MOB Military Occupational Specialty ORTT Operational Readiness Training Test-a field test REALTRAIN A...REAListic TRAINing simulation exercise SAM Surface-to-Air Missile SAT Scholastic Aptitude Test SQT Skill Qualification Test-an Army performance meas

How Accurate Is a Test Score?

ERIC Educational Resources Information Center

Doppelt, Jerome E.

1956-01-01

The standard error of measurement as a means for estimating the margin of error that should be allowed for in test scores is discussed. The true score measures the performance that is characteristic of the person tested; the variations, plus and minus, around the true score describe a characteristic of the test. When the standard deviation is used…

A Review of Standardized Tests of Nonverbal Oral and Speech Motor Performance in Children

ERIC Educational Resources Information Center

McCauley, Rebecca J.; Strand, Edythe A.

2008-01-01

Purpose: To review the content and psychometric characteristics of 6 published tests currently available to aid in the study, diagnosis, and treatment of motor speech disorders in children. Method: We compared the content of the 6 tests and critically evaluated the degree to which important psychometric characteristics support the tests' use for…

Job Characteristics, Work Involvement, and Job Performance of Public Servants

ERIC Educational Resources Information Center

Johari, Johanim; Yahya, Khulida Kirana

2016-01-01

Purpose: The primary purpose of this study is to assess the predicting role of job characteristics on job performance. Dimensions in the job characteristics construct are skill variety, task identity, task significance, autonomy and feedback. Further, work involvement is tested as a mediator in the hypothesized link. Design/methodology/approach: A…

Single Health System Adherence to 2012 Cervical Cancer Screening Guidelines at Extremes of Age and Posthysterectomy.

PubMed

Teoh, Deanna; Isaksson Vogel, Rachel; Hultman, Gretchen; Monu, Minnu; Downs, Levi; Geller, Melissa A; Le, Chap; Melton-Meaux, Genevieve; Kulasingam, Shalini

2017-03-01

To estimate the proportion of guideline nonadherent Pap tests in women aged younger than 21 years and older than 65 years and posthysterectomy in a single large health system. Secondary objectives were to describe temporal trends and patient and health care provider characteristics associated with screening in these groups. A retrospective cross-sectional chart review was performed at Fairview Health Services and University of Minnesota Physicians. Reasons for testing and patient and health care provider information were collected. Tests were designated as indicated or nonindicated per the 2012 cervical cancer screening guidelines. Point estimates and descriptive statistics were calculated. Patient and health care provider characteristics were compared between indicated and nonindicated groups using χ and Wilcoxon rank-sum tests. A total of 3,920 Pap tests were performed between September 9, 2012, and August 31, 2014. A total of 257 (51%; 95% confidence interval [CI] 46.1-54.9%) of tests in the younger than 21 years group, 536 (40%; 95% CI 37.7-43.1%) in the older than 65 years group, and 605 (29%; 95% CI 27.1-31.0%) in the posthysterectomy group were not indicated. White race in the older than 65 years group was the only patient characteristic associated with receipt of a nonindicated Pap test (P=.007). Health care provider characteristics associated with nonindicated Pap tests varied by screening group. Temporal trends showed a decrease in the proportion of nonindicated tests in the younger than 21 years group but an increase in the posthysterectomy group. For women aged younger than 21 years and older than 65 years and posthysterectomy, 35% of Pap tests performed in our health system were not guideline-adherent. There were no patient or health care provider characteristics associated with guideline nonadherent screening across all groups.

Determination of Functional Capabilities, the Level of Physical Performance and the State of Main Physiological Body Systems in the First Hours after the Accomplishment of Long-term Space Flights ("Field Test")

NASA Technical Reports Server (NTRS)

Kozlovskaya, Inesa; Tomilovskaya, Elena; Rukavishnikov, Ilya; Kitov, Vladimir; Reschke, Millard; Kofman, Igor

2014-01-01

Long-term stay in weightlessness is accompanied by alterations in the activity of main physiological body systems including sensory-motor, skeletal-muscular disturbances and cardiovascular deconditioning. However, up to now, there are no data on the state and level of functional performance of cosmonauts/astronauts directly after flight, nor are there data to help define the dynamic recovery of functional characteristics and work efficiency which are greatly needed to provide the safety and planning of their activity once they reach space objects. The Russian and American scientists are currently engaged in a joint experiment known as the "Field Test" with the goal of studying the functional performance and the state of main physiological body systems directly after landing and their temporal recovery dynamics. The functional performance is identified during the test by temporal characteristics of the movements of spatial translation, the stability of the vertical stance for 3.5 min, and the kinematic characteristics of walking - non-complicated and complicated. The following characteristics are identified as physiological characteristics of the test: a) orthostatic tolerance during stand test, b) back muscle tone; c) vertical stability - by characteristics of the correction responses to unexpected perturbations of the vertical stance, and d) support reactions during the performance of the full battery of tests. To date, a pilot version of the "Field Test" has been conducted with participation from four Russian cosmonauts. The results of studies have shown that in 1 - 5 hours after landing the functional abilities of the cosmonauts are considerably reduced. All the test movements at this time are considerably slower than preflight and the more complicated the task is, the greater significant reduction in orthostatic tolerance: during the first test that occurs 1 - 5 hours after landing. two of four cosmonauts declined to continue the task after the orthostatic test (one of them did not wear the anti-G suit "Centaurus" during testing). Blood pressure during moving out of prone posture to vertical stance in one of the cosmonauts and of sitting to standing position in the other dropped to the precollapse level. The results of the studies have confirmed the feasibility, the usefulness and the safety of conducting tests as close as possible to the landing. The program of "Field Test" experiment will be continued and extended.

Aerodynamic Performance of Hand Launch Glider

NASA Astrophysics Data System (ADS)

Koike, Masaru; Ishii, Mitsuru

In recent years Micro Air Vehicles (MAV) for disaster aerial video are developed vigorously. In order to improve aerodynamic performance of MAV wing performance in low Reynolds numbers (Re) need to be improved, but research on the theme are very rare. In category of Hand Launch Glider, a kind of model aircraft, glide performance are competed, as a result high performance airfoils in Re is around 20,000 are developed. Therefore for MAV's aerodynamic performance improvement airfoils of Hand Launch Gliders should be referred and aerodynamic characteristics of the airfoils desired to be studied. So in this research, aerodynamic characteristics of the gliders are measured in wind tunnel. And also consistency between wind tunnel test and glide test in calm air is examined to confirm reliability of wind tunnel test. Comparison of different airfoils and flow visualization are also performed.

47 CFR 2.1509 - Environmental and duration tests.

Code of Federal Regulations, 2011 CFR

2011-10-01

... above tests are to be performed on the same test unit. The tests in § 2.1509 (f) through (i) may be run... modulation characteristic tests in § 2.1513 of this part. Step (3) Perform the spectral tests in § 2.1515 of... extent possible for this test. (f) Float free and activation test. This test is required only for Class A...

Preliminary test results for Li-SOCl2 high-rate D cells

NASA Technical Reports Server (NTRS)

Bragg, Bobby J.; Johnson, Paul

1992-01-01

The performance and abuse characteristics of 55 D-size lithium-thionyl chloride (Li-SOCl2) cells are evaluated at relatively high rates. Results from the following tests are presented: shock test, vibration test, capacity performance, uninsulated short circuit, high temperature exposure, and overdischarge.

Preliminary test results for Li-SOCl2 high-rate D cells

NASA Astrophysics Data System (ADS)

Bragg, Bobby J.; Johnson, Paul

1992-02-01

The performance and abuse characteristics of 55 D-size lithium-thionyl chloride (Li-SOCl2) cells are evaluated at relatively high rates. Results from the following tests are presented: shock test, vibration test, capacity performance, uninsulated short circuit, high temperature exposure, and overdischarge.

Report on the State of Development, Availability, Evaluation, and Future use of Test Kits for the Measurement of Lead in Paint

EPA Science Inventory

The purpose of this issue paper is to address the availability and performance characteristics of portable lead test kits especially suited for lead in paint, procedures for evaluating the performance of these test kits, and the availability of performance evaluation (PE) materia...

Aerodynamics of High-Lift Configuration Civil Aircraft Model in JAXA

NASA Astrophysics Data System (ADS)

Yokokawa, Yuzuru; Murayama, Mitsuhiro; Ito, Takeshi; Yamamoto, Kazuomi

This paper presents basic aerodynamics and stall characteristics of the high-lift configuration aircraft model JSM (JAXA Standard Model). During research process of developing high-lift system design method, wind tunnel testing at JAXA 6.5m by 5.5m low-speed wind tunnel and Navier-Stokes computation on unstructured hybrid mesh were performed for a realistic configuration aircraft model equipped with high-lift devices, fuselage, nacelle-pylon, slat tracks and Flap Track Fairings (FTF), which was assumed 100 passenger class modern commercial transport aircraft. The testing and the computation aimed to understand flow physics and then to obtain some guidelines for designing a high performance high-lift system. As a result of the testing, Reynolds number effects within linear region and stall region were observed. Analysis of static pressure distribution and flow visualization gave the knowledge to understand the aerodynamic performance. CFD could capture the whole characteristics of basic aerodynamics and clarify flow mechanism which governs stall characteristics even for complicated geometry and its flow field. This collaborative work between wind tunnel testing and CFD is advantageous for improving or has improved the aerodynamic performance.

Exploring Academic Performance: Looking beyond Numerical Grades

ERIC Educational Resources Information Center

Martin Sanz, Noemy; Rodrigo, Inés G.; Izquierdo García, Cristina; Ajenjo Pastrana, Patricia

2017-01-01

Academic performance has always been associated to the evaluation tests results, which are those corresponding to student's IQ, and leaving aside other personal characteristics. Among such characteristics, the importance of emotional intelligence is worth highlighting (management, facilitation, understanding and perception), dimensions associated…

GROUND-WATER MODEL TESTING: SYSTEMATIC EVALUATION AND TESTING OF CODE FUNCTIONALITY AND PERFORMANCE

EPA Science Inventory

Effective use of ground-water simulation codes as management decision tools requires the establishment of their functionality, performance characteristics, and applicability to the problem at hand. This is accomplished through application of a systematic code-testing protocol and...

Rhythms of Mental Performance

ERIC Educational Resources Information Center

Valdez, Pablo; Reilly, Thomas; Waterhouse, Jim

2008-01-01

Cognitive performance is affected by an individual's characteristics and the environment, as well as by the nature of the task and the amount of practice at it. Mental performance tests range in complexity and include subjective estimates of mood, simple objective tests (reaction time), and measures of complex performance that require decisions to…

47 CFR 2.1513 - Measurements of modulation characteristics.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 1 2011-10-01 2011-10-01 false Measurements of modulation characteristics. 2.1513 Section 2.1513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS... Measurements of modulation characteristics. (a) Set-up. Test of modulation characteristics are to be performed...

47 CFR 2.1513 - Measurements of modulation characteristics.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Measurements of modulation characteristics. 2.1513 Section 2.1513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS... Measurements of modulation characteristics. (a) Set-up. Test of modulation characteristics are to be performed...

Frequency Characteristics of the MAGLEV Double-layered Propulsion Coil

NASA Astrophysics Data System (ADS)

Ema, Satoshi

The MAGLEV (magnetically levitated vehicle) is now well along in development testing at Yamanashi Test Line. The MAGLEV power source needs to supply a variable voltage and variable frequency to propulsion coils, which installed on outdoor guideway. The output voltage of the electric power converter contains many higher harmonics, which causes many troubles such as inductive interference. Accordingly, it is necessary to clarify the frequency characteristics of the propulsion coils and the power feeding circuit. In view of this situation, experiments and the theoretical analysis concerning the frequency characteristics of the propulsion coils with single-layer arrangement and the power feeding circuit at Miyazaki Test Line had been performed by the author. But the arrangement of the propulsion coils had been changed in Yamanashi Test Line from the single-layered coils to the double-layered coils for the stability of the super-conducting magnet on board. Thus, experiments and investigations concerning the frequency characteristics(resonance characteristics)of the propulsion coils with double-layer arrangement at Yamanashi Test Line have been performed but a theoretical analysis had not been done enough. A theoretical analysis was therefore done in this paper by applying the inverted L equivalent circuit with mutual inductance and capacitance to the propulsion coil, from which the positive and zero phase characteristics of the double-layered propulsion coils were analyzed.

Research on the Error Characteristics of a 110 kV Optical Voltage Transformer under Three Conditions: In the Laboratory, Off-Line in the Field and During On-Line Operation

PubMed Central

Xiao, Xia; Hu, Haoliang; Xu, Yan; Lei, Min; Xiong, Qianzhu

2016-01-01

Optical voltage transformers (OVTs) have been applied in power systems. When performing accuracy performance tests of OVTs large differences exist between the electromagnetic environment and the temperature variation in the laboratory and on-site. Therefore, OVTs may display different error characteristics under different conditions. In this paper, OVT prototypes with typical structures were selected to be tested for the error characteristics with the same testing equipment and testing method. The basic accuracy, the additional error caused by temperature and the adjacent phase in the laboratory, the accuracy in the field off-line, and the real-time monitoring error during on-line operation were tested. The error characteristics under the three conditions—laboratory, in the field off-line and during on-site operation—were compared and analyzed. The results showed that the effect of the transportation process, electromagnetic environment and the adjacent phase on the accuracy of OVTs could be ignored for level 0.2, but the error characteristics of OVTs are dependent on the environmental temperature and are sensitive to the temperature gradient. The temperature characteristics during on-line operation were significantly superior to those observed in the laboratory. PMID:27537895

Talent in Female Gymnastics: a Survival Analysis Based upon Performance Characteristics.

PubMed

Pion, J; Lenoir, M; Vandorpe, B; Segers, V

2015-11-01

This study investigated the link between the anthropometric, physical and motor characteristics assessed during talent identification and dropout in young female gymnasts. 3 cohorts of female gymnasts (n=243; 6-9 years) completed a test battery for talent identification. Performance-levels were monitored over 5 years of competition. Kaplan-Meier and Cox Proportional Hazards analyses were conducted to determine the survival rate and the characteristics that influence dropout respectively. Kaplan-Meier analysis indicated that only 18% of the female gymnasts that passed the baseline talent identification test survived at the highest competition level 5 years later. The Cox Proportional Hazards Model indicated that gymnasts with a score in the best quartile for a specific characteristic significantly increased chances of survival by 45-129%. These characteristics being: basic motor skills (129%), shoulder strength (96%), leg strength (53%) and 3 gross motor coordination items (45-73%). These results suggest that tests batteries commonly used for talent identification in young female gymnasts may also provide valuable insights into future dropout. Therefore, multidimensional test batteries deserve a prominent place in the selection process. The individual test results should encourage trainers to invest in an early development of basic physical and motor characteristics to prevent attrition. © Georg Thieme Verlag KG Stuttgart · New York.

Research on the Error Characteristics of a 110 kV Optical Voltage Transformer under Three Conditions: In the Laboratory, Off-Line in the Field and During On-Line Operation.

PubMed

Xiao, Xia; Hu, Haoliang; Xu, Yan; Lei, Min; Xiong, Qianzhu

2016-08-16

Optical voltage transformers (OVTs) have been applied in power systems. When performing accuracy performance tests of OVTs large differences exist between the electromagnetic environment and the temperature variation in the laboratory and on-site. Therefore, OVTs may display different error characteristics under different conditions. In this paper, OVT prototypes with typical structures were selected to be tested for the error characteristics with the same testing equipment and testing method. The basic accuracy, the additional error caused by temperature and the adjacent phase in the laboratory, the accuracy in the field off-line, and the real-time monitoring error during on-line operation were tested. The error characteristics under the three conditions-laboratory, in the field off-line and during on-site operation-were compared and analyzed. The results showed that the effect of the transportation process, electromagnetic environment and the adjacent phase on the accuracy of OVTs could be ignored for level 0.2, but the error characteristics of OVTs are dependent on the environmental temperature and are sensitive to the temperature gradient. The temperature characteristics during on-line operation were significantly superior to those observed in the laboratory.

Preliminary results of the mission profile life test of a 30 cm Hg bombardment thruster

NASA Technical Reports Server (NTRS)

Bechtel, R. T.; James, E. L.

1979-01-01

Long term tests were performed on a 30 cm Hg bombardment thruster and a power processing unit to determine lifetime characteristics. The thruster performance data and other operational characteristics taken at various times during the test segment are presented and evaluated with the life limiting mechanisms: discharge chamber erosion, deposition and spalling, external erosion, cathode degradation, and propellant isolator leakage. The control algorithms for thruster start up, steady state operation, throttle, detection and correction of off normal conditions, and shutdown are discussed.

Temperature-Dependent Characterization, Modeling, and Switching Speed-Limitation Analysis of Third-Generation 10-kV SiC MOSFET

DOE PAGES

Ji, Shiqi; Zheng, Sheng; Wang, Fei; ...

2017-07-06

The temperature-dependent characteristics of the third-generation 10-kV/20-A SiC MOSFET including the static characteristics and switching performance are carried out in this paper. The steady-state characteristics, including saturation current, output characteristics, antiparallel diode, and parasitic capacitance, are tested. Here, a double pulse test platform is constructed including a circuit breaker and gate drive with >10-kV insulation and also a hotplate under the device under test for temperature-dependent characterization during switching transients. The switching performance is tested under various load currents and gate resistances at a 7-kV dc-link voltage from 25 to 125 C and compared with previous 10-kV MOSFETs. A simplemore » behavioral model with its parameter extraction method is proposed to predict the temperature-dependent characteristics of the 10-kV SiC MOSFET. The switching speed limitations, including the reverse recovery of SiC MOSFET's body diode, overvoltage caused by stray inductance, crosstalk, heat sink, and electromagnetic interference to the control are discussed based on simulations and experimental results.« less

Temperature-Dependent Characterization, Modeling, and Switching Speed-Limitation Analysis of Third-Generation 10-kV SiC MOSFET

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

Ji, Shiqi; Zheng, Sheng; Wang, Fei

The temperature-dependent characteristics of the third-generation 10-kV/20-A SiC MOSFET including the static characteristics and switching performance are carried out in this paper. The steady-state characteristics, including saturation current, output characteristics, antiparallel diode, and parasitic capacitance, are tested. Here, a double pulse test platform is constructed including a circuit breaker and gate drive with >10-kV insulation and also a hotplate under the device under test for temperature-dependent characterization during switching transients. The switching performance is tested under various load currents and gate resistances at a 7-kV dc-link voltage from 25 to 125 C and compared with previous 10-kV MOSFETs. A simplemore » behavioral model with its parameter extraction method is proposed to predict the temperature-dependent characteristics of the 10-kV SiC MOSFET. The switching speed limitations, including the reverse recovery of SiC MOSFET's body diode, overvoltage caused by stray inductance, crosstalk, heat sink, and electromagnetic interference to the control are discussed based on simulations and experimental results.« less

SIRU utilization. Volume 1: Theory, development and test evaluation

NASA Technical Reports Server (NTRS)

Musoff, H.

1974-01-01

The theory, development, and test evaluations of the Strapdown Inertial Reference Unit (SIRU) are discussed. The statistical failure detection and isolation, single position calibration, and self alignment techniques are emphasized. Circuit diagrams of the system components are provided. Mathematical models are developed to show the performance characteristics of the subsystems. Specific areas of the utilization program are identified as: (1) error source propagation characteristics and (2) local level navigation performance demonstrations.

Health Behaviors and Standardized Test Scores: The Impact of School Health Climate on Performance

ERIC Educational Resources Information Center

Gunter, Whitney D.; Daly, Kevin

2013-01-01

Research has found that many characteristics are related to performance on standardized tests. Many of these are not necessarily "academic" attributes. One area of this research is on the connection between physical health or lifestyles and test performance. The research that exists in this area is often disconnected with each other and…

A descriptive-comparative study of performance characteristics in futsal players of different levels.

PubMed

Naser, Naser; Ali, Ajmol

2016-09-01

Despite the increasing popularity of futsal, there is little information on performance characteristics of players. We aimed to determine the validity and reliability of a futsal shooting test and to evaluate and compare performance characteristics of three futsal playing levels. Twenty-four males (n = 8 elite, n = 8 semi-elite, n = 8 social) completed two trials to examine the reliability of the Massey Futsal Shooting Test (MFST) and to compare various fitness characteristics between groups. MFST time taken (P = 0.010), shot speed (P < 0.001) and points scored per shot (P < 0.001) were better for elite relative to social players. Test-retest reliability was acceptable for all groups, but it was most repeatable in elite players. Loughborough Soccer Passing Test performance was better in elite relative to social players (P = 0.004). There were no differences in countermovement-jump height between groups. Elite players ran faster over 5 m than both semi-elite (P = 0.043) and social (P = 0.002) and faster than the social players through 10 m (P = 0.028) and 20 m (P = 0.026). Distance covered in the Futsal Intermittent Endurance Test was higher in elite relative to semi-elite (P = 0.005) and social (P < 0.001) groups. The MFST is a valid and reliable protocol to assess futsal shooting-skill performance; elite players have superior shooting and passing skill and have greater sprinting and intermittent-running ability.

Growth, reproductive performance, carcass characteristics and meat quality in F1 and F2 progenies of somatic cell-cloned pigs.

PubMed

Adachi, Noritaka; Yamaguchi, Daisuke; Watanabe, Akiyuki; Miura, Narumi; Sunaga, Seiji; Oishi, Hitoshi; Hashimoto, Michiko; Oishi, Takatsugu; Iwamoto, Masaki; Hanada, Hirofumi; Kubo, Masanori; Onishi, Akira

2014-04-24

The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production.

Growth, Reproductive Performance, Carcass Characteristics and Meat Quality in F1 and F2 Progenies of Somatic Cell-Cloned Pigs

PubMed Central

ADACHI, Noritaka; YAMAGUCHI, Daisuke; WATANABE, Akiyuki; MIURA, Narumi; SUNAGA, Seiji; OISHI, Hitoshi; HASHIMOTO, Michiko; OISHI, Takatsugu; IWAMOTO, Masaki; HANADA, Hirofumi; KUBO, Masanori; ONISHI, Akira

2014-01-01

The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production. PMID:24492641

A review of cryogenic testing performed by the thermochemical test branch, Manned Spacecraft Center in support of Apollo 13 and14

NASA Technical Reports Server (NTRS)

Propp, C. E.; Mcgee, J. M.

1971-01-01

The Apollo 13 anomaly provided considerable impetus for a variety of types of cryogenic and ignition tests. The logic of the various test program designs, the test techniques, and their final impact upon the investigation findings are described. In addition, several test programs initiated to determine the thermal performance and general performance characteristics of the redesigned Apollo 14 cryogenic storage system are presented.

Advanced Actuation Systems Development. Volume 2

DTIC Science & Technology

1989-08-01

and unloaded performance characteristics of a test specimen produced by General Dynamics Corporation as a feasibility model. The actuation system for...changing the camber of the test specimen is unique and was evaluated with a series of input/output measurements. The testing verified the general ...MAWS General ’rest Procedure........................................6 General Performance Measurements .................................... 10 Test

Assessment of a 40-kilowatt stirling engine for underground mining applications

NASA Technical Reports Server (NTRS)

Cairelli, J. E.; Kelm, G. G.; Slaby, J. G.

1982-01-01

An assessment of alternative power souces for underground mining applications was performed. A 40-kW Stirling research engine was tested to evaluate its performance and emission characteristics when operated with helium working gas and diesel fuel. The engine, the test facility, and the test procedures are described. Performance and emission data for the engine operating with helium working gas and diesel fuel are reported and compared with data obtained with hydrogen working gas and unleaded gasoline fuel. Helium diesel test results are compared with the characteristics of current diesel engines and other Stirling engines. External surface temperature data are also presented. Emission and temperature results are compared with the Federal requirements for diesel underground mine engines. The durability potential of Stirling engines is discussed on the basis of the experience gaind during the engine tests.

Validation of the LacTek test applied to spiked extracts of tissue samples: determination of performance characteristics.

PubMed

Mitchell, J M; Yee, A J; McNab, W B; Griffiths, M W; McEwen, S A

1999-01-01

LacTek tests are competitive enzyme-linked immunosorbent assays intended for rapid detection of antimicrobial residues in bovine milk. In this study, the LacTek test protocol was modified for use with extracts of bovine tissue to detect beta-lactam, tetracycline, and sulfamethazine residues. Test performance characteristics--precision, accuracy, ruggedness, practicability, and analytical specificity and sensitivity--were investigated. Results suggest that LacTek tests can be easily adapted to detect antimicrobial residues in extracts of lean ground beef. However, positive samples may not contain residues at violative concentrations (i.e., Canadian maximum residue limits), and therefore, additional analysis would be required for final confirmation and quantitation (e.g., chromatography).

Characteristics of Volcanic Soils in Landslide during the 2016 Kumamoto Earthquake, Japan

NASA Astrophysics Data System (ADS)

Hazarika, H.; Fukuoka, H.; Kokusho, T.; Sumartini, O.; Bhoopendra, D.

2017-12-01

There were many seismic subsidence, debris flows, landslides and slope failures, which occurred in Aso area due to the 2016 Kumamoto earthquake, Japan. This research aims to determine the failure mechanism of many mild slopes, and elucidate the strength characteristics of volcanic soils collected from the sites. A series of undrained static and cyclic triaxial tests, ring shear tests and direct shear tests were performed. Also, for further understanding of volcanic soils' material strength, X-ray powder diffraction analysis (XRD), X-ray fluorescence analysis (XRF), and Scanning electron microscope analysis (SEM) were performed. In this paper, preliminary results of the experimental testing program are discussed.

Learner Characteristics Predict Performance and Confidence in E-Learning: An Analysis of User Behavior and Self-Evaluation

ERIC Educational Resources Information Center

Jeske, Debora; Roßnagell, Christian Stamov; Backhaus, Joy

2014-01-01

We examined the role of learner characteristics as predictors of four aspects of e-learning performance, including knowledge test performance, learning confidence, learning efficiency, and navigational effectiveness. We used both self reports and log file records to compute the relevant statistics. Regression analyses showed that both need for…

Reverse bias voltage testing of 8 cm x 8cm silicon solar cells

NASA Technical Reports Server (NTRS)

Woike, T.; Stotlar, S.; Lungu, C.

1991-01-01

A study is described of the reverse I-V characteristics of the largest space qualified silicon solar cells currently available (8 x 8 cm) and of reverse bias voltage (RBV) testing performed on these cells. This study includes production grade cells, both with and without cover glass. These cells span the typical output range seen in production. Initial characteristics of these cells are measured at both 28 and 60 C. These measurements show weak correlation between cell output and reverse characteristics. Analysis is presented to determine the proper conditions for RBV stress to simulate shadowing effects on a particular array design. After performing the RBV stress the characteristics of the stressed cells are remeasured. The degradation in cell performance is highly variable which exacerbates cell mismatching over time. The effect of this degradation on array lifetime is also discussed. Generalization of these results to other array configurations is also presented.

Development of specification for the superpave simple performance tests (SPT).

DOT National Transportation Integrated Search

2009-05-16

This report describes the development and establishment of a proposed Simple Performance : Test (SPT) specification in order to contribute to the asphalt materials technology in the state of : Michigan. The properties and characteristic of materials,...

Performance, emissions, and physical characteristics of a rotating combustion aircraft engine

NASA Technical Reports Server (NTRS)

Berkowitz, M.; Hermes, W. L.; Mount, R. E.; Myers, D.

1976-01-01

The RC2-75, a liquid cooled two chamber rotary combustion engine (Wankel type), designed for aircraft use, was tested and representative baseline (212 KW, 285 BHP) performance and emissions characteristics established. The testing included running fuel/air mixture control curves and varied ignition timing to permit selection of desirable and practical settings for running wide open throttle curves, propeller load curves, variable manifold pressure curves covering cruise conditions, and EPA cycle operating points. Performance and emissions data were recorded for all of the points run. In addition to the test data, information required to characterize the engine and evaluate its performance in aircraft use is provided over a range from one half to twice its present power. The exhaust emissions results are compared to the 1980 EPA requirements. Standard day take-off brake specific fuel consumption is 356 g/KW-HR (.585 lb/BHP-HR) for the configuration tested.

Prechamber Compression-Ignition Engine Performance

NASA Technical Reports Server (NTRS)

Moore, Charles S; Collins, John H , Jr

1938-01-01

Single-cylinder compression-ignition engine tests were made to investigate the performance characteristics of prechamber type of cylinder head. Certain fundamental variables influencing engine performance -- clearance distribution, size, shape, and direction of the passage connecting the cylinder and prechamber, shape of prechamber, cylinder clearance, compression ratio, and boosting -- were independently tested. Results of motoring and of power tests, including several typical indicator cards, are presented.

Transfer function tests of the Joy longwall shearer

NASA Technical Reports Server (NTRS)

Fisher, P. H., Jr.

1978-01-01

A series of operational tests was performed on the Joy longwall shearer located at the Bureau of Mines in Bructon, Pennsylvania. The purpose of these tests was to determine the transfer function and operational characteristics of the system. These characteristics will be used to generate a simulation model of the longwall shearer used in the development of the closed-loop vertical control system.

An Investigation of the Gender Differential Performance on a High-Stakes Language Proficiency Test in Iran

ERIC Educational Resources Information Center

Karami, Hossein

2013-01-01

There has been a growing consensus among the educational measurement experts and psychometricians that test taker characteristics may unduly affect the performance on tests. This may lead to construct-irrelevant variance in the scores and thus render the test biased. Hence, it is incumbent on test developers and users alike to provide evidence…

A Multidimensional Perspective of College Readiness: Relating Student and School Characteristics to Performance on the ACT®. ACT Research Report Series 2015 (6)

ERIC Educational Resources Information Center

McNeish, Daniel M.; Radunzel, Justine; Sanchez, Edgar

2015-01-01

This study examined the contributions of students' noncognitive characteristics toward explaining performance on the ACT® test, over and above traditional predictors such as high school grade point average (HSGPA), coursework taken, and school characteristics. The sample consisted of 6,440 high school seniors from 4,541 schools who took the ACT in…

40 CFR Figure E-1 to Subpart E of... - Designation Testing Checklist

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Field Sampling Procedure (§ 53.30, .31, .34) Design Specification Tests Filter (L-6) Range of... Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II... Process or of Documented Evidence: Performance, Design or Application Spec. Corresponding to Sections of...

40 CFR Figure E-1 to Subpart E of... - Designation Testing Checklist

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Field Sampling Procedure (§ 53.30, .31, .34) Design Specification Tests Filter (L-6) Range of... Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II... Process or of Documented Evidence: Performance, Design or Application Spec. Corresponding to Sections of...

40 CFR Figure E-1 to Subpart E of... - Designation Testing Checklist

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Field Sampling Procedure (§ 53.30, .31, .34) Design Specification Tests Filter ( L-6) Range of... Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II... Process or of Documented Evidence: Performance, Design or Application Spec. Corresponding to Sections of...

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.

The Physical and Athletic Performance Characteristics of Division I Collegiate Female Soccer Players by Position.

PubMed

Lockie, Robert G; Moreno, Matthew R; Lazar, Adrina; Orjalo, Ashley J; Giuliano, Dominic V; Risso, Fabrice G; Davis, DeShaun L; Crelling, Jeff B; Lockwood, John R; Jalilvand, Farzad

2018-02-01

Lockie, RG, Moreno, MR, Lazar, A, Orjalo, AJ, Giuliano, DV, Risso, FG, Davis, DL, Crelling, JB, Lockwood, JR, and Jalilvand, F. The physical and athletic performance characteristics of Division I collegiate female soccer players by position. J Strength Cond Res 32(2): 334-343, 2018-Playing positions in soccer can exhibit different movement demands during a match, contributing to variations in physical and performance characteristics. National Collegiate Athletic Association (NCAA) soccer features different substitution rules when compared to FIFA-sanctioned matches, which could influence each players' characteristics. Therefore, this study determined the athletic performance characteristics of Division I female soccer players. Twenty-six players (3 goalkeepers; 8 defenders; 10 midfielders; 5 forwards) from the same squad completed assessments of: lower-body power (vertical and standing broad jump); linear (0-5, 0-10, 0-30 meter [m] sprint intervals) and change-of-direction (pro-agility shuttle; arrowhead change-of-direction speed test) speed; and soccer-specific fitness (Yo-Yo Intermittent Recovery Test [YYIRT] levels 1 and 2). Players were split into position groups, and a Kruskal-Wallis H test with post hoc pairwise analyses (p ≤ 0.05) calculated significant between-group differences. There were no differences in age, height, or body mass between the positions. Midfielders had a faster 0-5 m time compared with the defenders (p = 0.017) and the goalkeepers (p = 0.030). The defenders (p = 0.011) and midfielders (p = 0.013) covered a greater YYIRT2 distance compared with the goalkeepers. There were no other significant between-position differences. Overall, Division I collegiate female players from the same squad demonstrated similar characteristics as measured by soccer-specific performance tests, which could allow for flexibility in position assignments. However, a relatively homogenous squad could also indicate commonality in training prescription, particularly regarding acceleration and high-intensity running. Strength and conditioning coaches may have to consider the specific movement demands of individual positions when training these capacities.

Summary of directional divergence characteristics of several high performance aircraft configurations

NASA Technical Reports Server (NTRS)

Greer, H. D.

1972-01-01

The present paper summarizes the high-angle-of-attack characteristics of a number of high-performance aircraft as determined from model force tests and free-flight model tests and correlates these characteristics with the dynamic directional-stability parameter. This correlation shows that the dynamic directional-stability parameter correlates fairly well with directional divergence. Data are also presented to show the effect of some airframe modifications on the directional divergence potential of the configuration. These results show that leading-edge slates seem to be the most effective airframe modification for reducing or eliminating the directional divergence potential of aircraft with moderately swept wings.

SGC Tests for Influence of Material Composition on Compaction Characteristic of Asphalt Mixtures

PubMed Central

Chen, Qun

2013-01-01

Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes. PMID:23818830

SGC tests for influence of material composition on compaction characteristic of asphalt mixtures.

PubMed

Chen, Qun; Li, Yuzhi

2013-01-01

Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes.

Aerodynamic and propeller performance characteristics of a propfan-powered, semispan model

NASA Technical Reports Server (NTRS)

Levin, Alan D.; Smith, Ronald C.; Wood, Richard D.

1985-01-01

A semispan wing/body model with a powered propeller was tested to provide data on a total powerplant installation drag penalty of advanced propfan-powered aircraft. The test objectives were to determine the total power plant installation drag penalty on a representative propfan aircraft; to study the effect of configuration modifications on the installed powerplant drag; and to determine performance characteristics of an advanced design propeller which was mounted on a representative nacelle in the presence of a wing.

A study on the performance and emission characteristics of esterified pinnai oil tested in VCR engine.

PubMed

Ashok Kumar, T; Chandramouli, R; Mohanraj, T

2015-11-01

Biodiesel is a clean renewable fuel derived from vegetable oils and animal fats. It is biodegradable, oxygenated, non toxic and free from sulfur and aromatics. The biodiesel prepared from pinnai oil undergoes acid esterification followed by alkaline transesterification process. The fatty acid methyl esters components were identified using gas chromatography and compared with the standard properties. The properties of biodiesel are comparable with diesel. The yield of the biodiesel production depends upon the process parameters such as reaction temperature, pH, time duration and amount of catalyst. The yield of biodiesel by transesterification process was 73% at 55°C. This fuel was tested in a variable compression ratio engine with blend ratios of B10 and B20. During the test runs the compression ratio of the engine was varied from 15:1 to 18:1 and the torque is adjusted from zero to maximum value of 22Nm. The performance characteristics such as the brake thermal efficiency, brake specific energy consumption and exhaust gas temperature of the engine are analyzed. The combustion characteristics of biodiesel like ignition delay, combustion duration and maximum gas temperature and the emission characteristics are also analyzed. The performance characteristics, combustion characteristics and engine emission are effective in the variable compression ratio engine with biodiesel and it is compared with diesel. Copyright © 2015 Elsevier Inc. All rights reserved.

Experimental Evaluation of a Low Emissions High Performance Duct Burner for Variable Cycle Engines (VCE)

NASA Technical Reports Server (NTRS)

Lohmann, R. P.; Mador, R. J.

1979-01-01

An evaluation was conducted with a three stage Vorbix duct burner to determine the performance and emissions characteristics of the concept and to refine the configuration to provide acceptable durability and operational characteristics for its use in the variable cycle engine (VCE) testbed program. The tests were conducted at representative takeoff, transonic climb, and supersonic cruise inlet conditions for the VSCE-502B study engine. The test stand, the emissions sampling and analysis equipment, and the supporting flow visualization rigs are described. The performance parameters including the fuel-air ratio, the combustion efficiency/exit temperature, thrust efficiency, and gaseous emissions calculations are defined. The test procedures are reviewed and the results are discussed.

Protection of Conductive and Non-conductive Advanced Polymer-based Paints from Highly Aggressive Oxidative Environments

NASA Technical Reports Server (NTRS)

Gudimenko, Y.; Ng, R.; Iskanderova, Z.; Kleiman, J.; Grigorevsky, A.; Kiseleva, L.; Finckenor, M.; Edwards, D.

2005-01-01

Research has been continued to further improve the space durability of conductive and non-conductive polymer-based paints and of conductive thermal control paints for space applications. Efforts have been made to enhance the space durability and stability of functional Characteristics in ground-based space environment imitating conditions, using specially developed surface modification treatment. The results of surface modification of new conductive paints, including the ground-based testing in aggressive oxidative environments, such as atomic oxygen/UV and oxygen plasma, and performance evaluation are presented. Functional properties and performance characteristics, such as thermal optical properties (differential solar absorptance and thermal emittance representing the thermal optical performance of thermal control paints) and surface resistivity characteristics of pristine, surface modified, and tested materials were verified. Extensive surface analysis studies have been performed using complementary surface analyses including SEM/EDS and XPS. Test results revealed that the successfully treated materials exhibit reduced mass loss and no surface morphology change, thus indicating good protection from the severe oxidative environment. It was demonstrated that the developed surface modification treatment could be applied successfully to charge dissipative and conductive paints.

Combined effects of hydrazine exposure and endurance testing on solenoid-actuated valve performance

NASA Technical Reports Server (NTRS)

Hagler, R., Jr.

1974-01-01

Results are presented from a test program which was conducted to assess the capability of various solenoid-actuated valve design concepts to provide performance characteristics commensurate with long-duration (ten-year) missions to explore the outer planets. The valves were installed in a hydrazine flow test setup and periodically cycled during a nine-month test period under test conditions comparable to anticipated mission operating conditions. In situ valve performance was periodically determined, and leakage was continuously monitored.

Generic anthropometric and performance characteristics among elite adolescent boys in nine different sports.

PubMed

Pion, Johan; Segers, Veerle; Fransen, Job; Debuyck, Gijs; Deprez, Dieter; Haerens, Leen; Vaeyens, Roel; Philippaerts, Renaat; Lenoir, Matthieu

2015-01-01

The aim of the present study was to evaluate the Flemish Sports Compass (FSC), a non-sport-specific generic testing battery. It was hypothesised that a set of 22 tests would have sufficient discriminant power to allocate athletes to their own sport based on a unique combination of test scores. First, discriminant analyses were applied to the 22 tests of anthropometry, physical fitness and motor coordination in 141 boys under age 18 (16.1 ± 0.8 years) and post age at peak height velocity (maturity offset = 2.674 ± 0.926) from Flemish Top Sport Academies for badminton, basketball, gymnastics, handball, judo, soccer, table tennis, triathlon and volleyball. Second, nine sequential discriminant analyses were used to assess the ability of a set of relevant performance characteristics classifying participants and non-participants for the respective sports. Discriminant analyses resulted in a 96.4% correct classification of all participants for the nine different sports. When focusing on relevant performance characteristics, 80.1% to 97.2% of the total test sample was classified correctly within their respective disciplines. The discriminating characteristics were briefly the following: flexibility in gymnastics, explosive lower-limb strength in badminton and volleyball, speed and agility in badminton, judo, soccer and volleyball, upper-body strength in badminton, basketball and gymnastics, cardiorespiratory endurance in triathletes, dribbling skills in handball, basketball and soccer and overhead-throwing skills in badminton and volleyball. The generic talent characteristics of the FSC enable the distinction of adolescent boys according to their particular sport. Implications for talent programmes are discussed.

Establishment of key grid-connected performance index system for integrated PV-ES system

NASA Astrophysics Data System (ADS)

Li, Q.; Yuan, X. D.; Qi, Q.; Liu, H. M.

2016-08-01

In order to further promote integrated optimization operation of distributed new energy/ energy storage/ active load, this paper studies the integrated photovoltaic-energy storage (PV-ES) system which is connected with the distribution network, and analyzes typical structure and configuration selection for integrated PV-ES generation system. By combining practical grid- connected characteristics requirements and technology standard specification of photovoltaic generation system, this paper takes full account of energy storage system, and then proposes several new grid-connected performance indexes such as paralleled current sharing characteristic, parallel response consistency, adjusting characteristic, virtual moment of inertia characteristic, on- grid/off-grid switch characteristic, and so on. A comprehensive and feasible grid-connected performance index system is then established to support grid-connected performance testing on integrated PV-ES system.

JWST center of curvature test method and results

NASA Astrophysics Data System (ADS)

Saif, Babak; Chaney, David; Greenfield, Perry; Van Gorkom, Kyle; Brooks, Keira; Hack, Warren; Bluth, Marcel; Bluth, Josh; Sanders, James; Smith, Koby; Carey, Larkin; Chaung, Sze; Keski-Kuha, Ritva; Feinberg, Lee; Tournois, Severine; Smith, W. Scott; Kradinov, Vladimir

2017-09-01

The James Webb Space Telescope (JWST) recently saw the completion of the assembly process for the Optical Telescope Element and Integrated Science Instrument Module (OTIS). This integration effort was performed at Goddard Space Flight Center (GSFC) in Greenbelt, Maryland. In conjunction with this assembly process a series of vibration and acoustic tests were performed. To help assure the telescope's primary mirror was not adversely impacted by this environmental testing an optical center of curvature (CoC) test was performed to measure changes in the mirror's optical performance. The primary is a 6.5 meter diameter mirror consisting of 18 individual hexagonal segments. Each segment is an off-axis asphere. There are a total of three prescriptions repeated six times each. As part of the CoC test each segment was individually measured using a high-speed interferometer (HSI) designed and built specifically for this test. This interferometer is capable of characterizing both static and dynamic characteristics of the mirrors. The latter capability was used, with the aid of a vibration stinger applying a low-level input force, to measure the dynamic characteristic changes of the PM backplane structure. This paper describes the CoC test setup, an innovative alignment method, and both static and dynamic test results.

The Conceptual Design for a Fuel Assembly of a New Research Reactor

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

Ryu, J-S.; Cho, Y-G.; Yoon, D-B.

2004-10-06

A new Research Reactor (ARR) has been under design by KAERI since 2002. In this work, as a first step for the design of the fuel assembly of the ARR, the conceptual design has been carried out. The vibration characteristics of the tubular fuel model and the locking performance of the preliminary designed locking devices were investigated. In order to investigate the effects of the stiffener on the vibration characteristics of the tubular fuel, a modal analysis was performed for the finite element models of the tubular fuels with stiffeners and without stiffeners. The analysis results show that the vibrationmore » characteristics of the tubular fuel with stiffeners are better than those of the tubular fuel without stiffeners. To investigate the locking performance of the preliminary designed locking devices for the fuel assembly of the ARR, the elements of the locking devices were fabricated. Then the torsional resistance, fixing status and vibration characteristics of the locking devices were tested. The test results show that using the locking device with fins on the bottom guide can prevent the torsional motion of the fuel assembly, and that additional springs or guides on the top of the fuel assembly are needed to suppress the lateral motion of the fuel assembly. Based on the modal analysis and experimental results, the fuel assembly and locking devices of the ARR were designed and its prototype was fabricated. The locking performance, pressure drop characteristics and vibration characteristics of the newly designed fuel assembly will be tested in the near future.« less

Technique for Measuring Speed and Visual Motion Sensitivity in Lizards

ERIC Educational Resources Information Center

Woo, Kevin L.; Burke, Darren

2008-01-01

Testing sensory characteristics on herpetological species has been difficult due to a range of properties related to physiology, responsiveness, performance ability, and the type of reinforcer used. Using the Jacky lizard as a model, we outline a successfully established procedure in which to test the visual sensitivity to motion characteristics.…

Relationships Between Design Characteristics of Avionics Subsystems and Training Cost, Training Difficulty, and Job Performance. Final Report, Covering Activity from 1 July 1971 Through 1 September 1972.

ERIC Educational Resources Information Center

Lintz, Larry M.; And Others

A study investigated the relationship between avionics subsystem design characteristics and training time, training cost, and job performance. A list of design variables believed to affect training and job performance was established and supplemented with personnel variables, including aptitude test scores and the amount of training and…

Aeroelastic characteristics of the AH-64 bearingless tail rotor

NASA Technical Reports Server (NTRS)

Banerjee, D.

1988-01-01

The results of a wind tunnel test program to determine the performance loads and dynamic characteristics of the Composite Flexbeam Tail Rotor (CFTR) for the AH-64 Advanced Attack Helicopter are reported. The CFTR uses an elastomeric shear attachment of the flexbeam to the hub to provide soft-inplane S-mode and stiff-inplane C-mode configuration. The properties of the elastomer were selected for proper frequency placement and scale damping of the inplane S-mode. Kinematic pitch-lag coupling was introduced to provide the first cyclic inplane C-mode damping at high collective pitch. The CFTR was tested in a wind tunnel over the full slideslip envelop of the AH-64. It is found that the rotor was aeroelastically stable throughout the complete collective pitch range and up to rotor speeds of 1403 rpm. The dynamic characteristics of the rotor were found to be satisfactory at all pitch angles and rotor speeds of the tunnel tests. The design characteristics of the rotor which permit the high performance characteristics are discussed. Several schematic drawings and photographs of the rotor are provided.

Performance characteristics of proximity focused ultraviolet image converters

NASA Technical Reports Server (NTRS)

Williams, J. T.; Feibelman, W. A.

1973-01-01

Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for ultraviolet to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs - Te photocathodes, and P-11 phosphors on fiber optic output windows.

Performance characteristics of proximity focused ultraviolet image converters

NASA Technical Reports Server (NTRS)

Williams, J. T.; Feibelman, W. A.

1973-01-01

Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for UV to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs-Te photocathodes and P-11 phosphors on fiber optic output windows.

Gender and Learner Characteristics

ERIC Educational Resources Information Center

Hindal, Huda; Reid, Norman; Whitehead, Rex

2013-01-01

It is well established that girls and boys perform differently in traditional examinations in most countries. This study looks at a sample of 754 school students in Kuwait (aged about 13) and explores how boys and girls differ in the performance in a range of tests related to learner characteristics. The fundamental question is how boys and girls…

Characteristics of a 30-cm thruster operated with small hole accelerator grid ion optics

NASA Technical Reports Server (NTRS)

Vahrenkamp, R. P.

1976-01-01

Small hole accelerator grid ion optical systems have been tested as a possible means of improving 30-cm ion thruster performance. The effects of small hole grids on the critical aspects of thruster operation including discharge chamber performance, doubly-charged ion concentration, effluent beam characteristics, and plasma properties have been evaluated. In general, small hole accelerator grids are beneficial in improving thruster performance while maintaining low double ion ratios. However, extremely small accelerator aperture diameters tend to degrade beam divergence characteristics. A quantitative discussion of these advantages and disadvantages of small hole accelerator grids, as well as resulting variations in thruster operation characteristics, is presented.

Hospital ownership, decisions on supervisory board characteristics, and financial performance.

PubMed

Kuntz, Ludwig; Pulm, Jannis; Wittland, Michael

2016-01-01

Dynamic and complex transformations in the hospital market increase the relevance of good corporate governance. However, hospital performance and the characteristics of supervisory boards differ depending on ownership. The question therefore arises whether hospital owners can influence performance by addressing supervisory board characteristics. The objective of this study is to explain differences in the financial performance of hospitals with regard to ownership by studying the size and composition of supervisory boards. The AMADEUS database was used to collect information on hospital financial performance in 2009 and 2010. Business and quality reports, hospital websites, and data from health insurer were used to obtain information on hospital and board characteristics. The resulting sample consisted of 175 German hospital corporations. We utilized ANOVA and regression analysis to test a mediation hypothesis that investigated whether decisions regarding board size and composition were associated with financial performance and could explain performance differences. Financial performance and board size and composition depend on ownership. An increase in board size and greater politician participation were negatively associated with all five tested measures of financial performance. Furthermore, an increase in physician participation was positively associated with one dimension of financial performance, whereas one negative relationship was identified for nurse and economist participation. For clerics, no associations were found. Decisions concerning board size and composition are important as they relate to hospital financial performance. We contribute to existing research by showing that, in addition to board size and physician participation, the participation of other professionals can also influence financial performance.

A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research Aircraft

NASA Technical Reports Server (NTRS)

Quigley, H. C.; Innis, R. C.; Grossmith, S.

1974-01-01

The flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator test results; (3) to contribute to the development of criteria for design and operation of jet STOL transport aircraft; and (4) to provide a jet STOL transport aircraft for STOL systems research and development. Results obtained during the first 8 months of proof-of-concept flight testing of the aircraft in STOL configurations are reported. Included are a brief description of the aircraft, fan-jet engines, and systems; a discussion of the aerodynamic, stability and control, and STOL performance; and pilot opinion of the handling qualities and operational characteristics.

Development of advanced fuel cell system, phase 2

NASA Technical Reports Server (NTRS)

Handley, L. M.; Meyer, A. P.; Bell, W. F.

1973-01-01

A multiple task research and development program was performed to improve the weight, life, and performance characteristics of hydrogen-oxygen alkaline fuel cells for advanced power systems. Development and characterization of a very stable gold alloy catalyst was continued from Phase I of the program. A polymer material for fabrication of cell structural components was identified and its long term compatibility with the fuel cell environment was demonstrated in cell tests. Full scale partial cell stacks, with advanced design closed cycle evaporative coolers, were tested. The characteristics demonstrated in these tests verified the feasibility of developing the engineering model system concept into an advanced lightweight long life powerplant.

Investigation of the Effects of Facility Background Pressure on the Performance and Voltage-Current Characteristics of the High Voltage Hall Accelerator

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Huang, Wensheng; Haag, Thomas; Spektor, Rostislav

2014-01-01

The National Aeronautics and Space Administration (NASA) Science Mission Directorate In-Space Propulsion Technology office is sponsoring NASA Glenn Research Center to develop a 4 kW-class Hall thruster propulsion system for implementation in NASA science missions. A study was conducted to assess the impact of varying the facility background pressure on the High Voltage Hall Accelerator (HiVHAc) thruster performance and voltage-current characteristics. This present study evaluated the HiVHAc thruster performance in the lowest attainable background pressure condition at NASA GRC Vacuum Facility 5 to best simulate space-like conditions. Additional tests were performed at selected thruster operating conditions to investigate and elucidate the underlying physics that change during thruster operation at elevated facility background pressure. Tests were performed at background pressure conditions that are three and ten times higher than the lowest realized background pressure. Results indicated that the thruster discharge specific impulse and efficiency increased with elevated facility background pressure. The voltage-current profiles indicated a narrower stable operating region with increased background pressure. Experimental observations of the thruster operation indicated that increasing the facility background pressure shifted the ionization and acceleration zones upstream towards the thrusters anode. Future tests of the HiVHAc thruster are planned at background pressure conditions that are expected to be two to three times lower than what was achieved during this test campaign. These tests will not only assess the impact of reduced facility background pressure on thruster performance, voltage-current characteristics, and plume properties; but will also attempt to quantify the magnitude of the ionization.

Evaluation of wet tantalum capacitors after exposure to extended periods of ripple current, volume 1

NASA Technical Reports Server (NTRS)

Watson, G. W.; Lasharr, J. C.; Shumaker, M. J.

1974-01-01

The application of tantalum capacitors in the Viking Lander includes both dc voltage and ripple current electrical stress, high temperature during nonoperating times (sterilization), and high vibration and shock loads. The capacitors must survive these severe environments without any degradation if reliable performance is to be achieved. A test program was established to evaluate both wet-slug tantalum and wet-foil capacitors under conditions accurately duplicating actual Viking applications. Test results of the electrical performance characteristics during extended periods of ripple current, the characteristics of the internal silver migration as a function for extended periods of ripple current, and the existence of any memory characteristics are presented.

Evaluation of wet tantalum capacitors after exposure to extended periods of ripple current, volume 2

NASA Technical Reports Server (NTRS)

Ward, C. M.

1975-01-01

The application of tantalum capacitors in the Viking Lander includes dc voltage and ripple current electrical stress, high temperature during nonoperating times (sterilization), and high vibration and shock loads. The capacitors must survive these severe environments without any degradation if reliable performance is to be achieved. A test program was established to evaluate both wet-slug tantalum and wet-foil capacitors under conditions accurately duplicating actual Viking applications. Test results of the electrical performance characteristics during extended periods of ripple current, the characteristics of the internal silver migration as a function of extended periods of ripple current, and the existence of any memory characteristics are presented.

Aerodynamics of the Viggen 37 aircraft. Part 1: General characteristics at low speed

NASA Technical Reports Server (NTRS)

Karling, K.

1986-01-01

A description of the aerodynamics of the Viggen 37 and its performances, especially at low speeds is presented. The aerodynamic requirements for the design of the Viggen 37 aircraft are given, including the basic design, performance requirement, and aerodynamic characteristics, static and dynamic load test results and flight test results. The Viggen 37 aircraft is designed to be used for air attack, surveillance, pursuit, and training applications. It is shown that this aircraft is suitable for short runways, and has good maneuvering, acceleration, and climbing characteristics. The design objectives for this aircraft were met by utilizing the effect produced by the interference between two triangular wings, positioned in tandem.

Piezocone Penetration Testing Device

DOT National Transportation Integrated Search

2017-01-03

Hydraulic characteristics of soils can be estimated from piezocone penetration test (called PCPT hereinafter) by performing dissipation test or on-the-fly using advanced analytical techniques. This research report presents a method for fast estimatio...

SCPS-TP, TCP, and Rate-Based Protocol Evaluation. Revised

NASA Technical Reports Server (NTRS)

Tran, Diepchi T.; Lawas-Grodek, Frances J.; Dimond, Robert P.; Ivancic, William D.

2005-01-01

Tests were performed at Glenn Research Center to compare the performance of the Space Communications Protocol Standard Transport Protocol (SCPS TP, otherwise known as "TCP Tranquility") relative to other variants of TCP and to determine the implementation maturity level of these protocols, particularly for higher speeds. The testing was performed over reasonably high data rates of up to 100 Mbps with delays that are characteristic of near-planetary environments. The tests were run for a fixed packet size, but for variously errored environments. This report documents the testing performed to date.

Development of a morphing flap using shape memory alloy actuators: the aerodynamic characteristics of a morphing flap

NASA Astrophysics Data System (ADS)

Ko, Seung-Hee; Bae, Jae-Sung; Rho, Jin-Ho

2014-07-01

The discontinuous contour of a wing with conventional flaps diminishes the aerodynamic performance of an aircraft. A wing with a continuous contour does not experience extreme flow stream fluctuations during flight, and consequently has good aerodynamic characteristics. In this study, a morphing flap using shape memory alloy actuators is proposed, designed and fabricated, and its aerodynamic characteristics are investigated using aerodynamic analyses and wind tunnel tests. The ribs of the morphing flap are designed and fabricated with multiple elements joined together in a way that allows relative rotations of adjacent elements and forms a smooth contour of the morphing flap. The aerodynamic analyses of this multiple-element morphing-flap wing are performed using XFLR pro; its aerodynamic performance is compared with that of a mechanical-flap wing, and is measured through wind-tunnel tests.

Hydrodynamic air lubricated compliant surface bearing for an automotive gas turbine engine. 1: Journal bearing performance

NASA Technical Reports Server (NTRS)

Ruscitto, D.; Mccormick, J.; Gray, S.

1978-01-01

A 38.1 mm (1.5 inch) diameter Hydresil Compliant Surface Air Lubricated Journal Bearing was designed and tested to obtain bearing performance characteristics at both room temperature and 315 C (600 F). Testing was performed at various speeds up to 60,000 rpm with varying loads. Rotating sensors provided an opportunity to examine the film characteristics of the compliant surface bearing. In addition to providing minimum film thickness values and profiles, many other insights into bearing operation were gained such as the influence of bearing fabrication accuracy and the influence of smooth foil deflection between the bumps.

General practice variation in spirometry testing among patients receiving first-time prescriptions for medication targeting obstructive lung disease in Denmark: a population-based observational study

PubMed Central

2013-01-01

Background Spirometry testing is essential to confirm an obstructive lung disease, but studies have reported that a large proportion of patients diagnosed with COPD or asthma have no history of spirometry testing. Also, it has been shown that many patients are prescribed medication for obstructive lung disease without a relevant diagnosis or spirometry test registered. General practice characteristics have been reported to influence diagnosis and management of several chronic diseases. However, these findings are inconsistent, and it is uncertain whether practice characteristics influence spirometry testing among patients receiving medication for obstructive lung disease. The aim of this study was therefore to examine if practice characteristics are associated with spirometry testing among patients receiving first-time prescriptions for medication targeting obstructive lung disease. Methods A national register-based cohort study was performed. All patients over 18 years receiving first-time prescriptions for medication targeting obstructive lung disease in 2008 were identified and detailed patient-specific data on sociodemographic status and spirometry tests were extracted. Information on practice characteristics like number of doctors, number of patients per doctor, training practice status, as well as age and gender of the general practitioners was linked to each medication user. Results Partnership practices had a higher odds ratio (OR) of performing spirometry compared with single-handed practices (OR 1.24, CI 1.09-1.40). We found a significant association between increasing general practitioner age and decreasing spirometry testing. This tendency was most pronounced among partnership practices, where doctors over 65 years had the lowest odds of spirometry testing (OR 0.25, CI 0.10-0.61). Training practice status was significantly associated with spirometry testing among single-handed practices (OR 1.40, CI 1.10-1.79). Conclusion Some of the variation in spirometry testing among patients receiving first-time prescriptions for medication targeting obstructive lung disease was associated with practice characteristics. This variation in performance may indicate a potential for quality improvement. PMID:23923987

Performance Testing of Yardney Li-Ion Cells and Batteries in Support of Future NASA Missions

NASA Technical Reports Server (NTRS)

Smart, M. C.; Ratnakumar, B. V.; Whitcanack, L. D.; Puglia, F. J.; Santee, S.; Gitzendanner, R.

2009-01-01

NASA requires lightweight rechargeable batteries for future missions to Mars and the outer planets that are capable of operating over a wide range of temperatures, with high specific energy and energy densities. Due to the attractive performance characteristics, Li-ion batteries have been identified as the battery chemistry of choice for a number of future applications. For example, JPL is planning to launch another unmanned rover mission to the planet Mars. This mission, referred to as the Mars Science Laboratory (MSL), will involve the use of a rover that is much larger than the previously developed Spirit and Opportunity Rovers for the 2003 Mars Exploration Rover (MER) mission, that are currently still in operation on the surface of the planet after more than five years. Part of the reason that the MER rovers have operated so successfully, far exceeding the required mission duration of 90 sols, is that they possess robust Li-ion batteries, manufactured by Yardney Technical Products, which have demonstrated excellent life characteristics. Given the excellent performance characteristics displayed, similar Li-ion batteries have been projected to successfully meet the mission requirements of the up-coming MSL mission. In addition to future missions to Mars, Li-ion technology is attractive for a number of other future NASA applications which require high specific energy, rechargeable batteries. To ascertain the viability of using Li-ion batteries for these applications, a number of performance validation tests have been performed on both Yardney cells and batteries of various sizes. These tests include mission simulation tests, charge and discharge rate characterization testing, cycle life testing under various conditions, and storage testing.

Preliminary flight-test results of an advanced technology light twin-engine airplane /ATLIT/

NASA Technical Reports Server (NTRS)

Holmes, B. J.; Kohlman, D. L.; Crane, H. L.

1976-01-01

The present status and flight-test results are presented for the ATLIT airplane. The ATLIT is a Piper PA-34 Seneca I modified by the installation of new wings incorporating the GA(W)-1 (Whitcomb) airfoil, reduced wing area, roll-control spoilers, and full-span Fowler flaps. Flight-test results on stall and spoiler roll characteristics show good agreement with wind-tunnel data. Maximum power-off lift coefficients are greater than 3.0 with flaps deflected 37 deg. With flaps down, spoiler deflections can produce roll helix angles in excess of 0.11 rad. Flight testing is planned to document climb and cruise performance, and supercritical propeller performance and noise characteristics. The airplane is scheduled for testing in the NASA-Langley Research Center Full-Scale Tunnel.

Structural Model for the Effects of Environmental Elements on the Psychological Characteristics and Performance of the Employees of Manufacturing Systems

PubMed Central

Realyvásquez, Arturo; Maldonado-Macías, Aidé Aracely; García-Alcaraz, Jorge; Cortés-Robles, Guillermo; Blanco-Fernández, Julio

2016-01-01

This paper analyzes the effects of environmental elements on the psychological characteristics and performance of employees in manufacturing systems using structural equation modeling. Increasing the comprehension of these effects may help optimize manufacturing systems regarding their employees’ psychological characteristics and performance from a macroergonomic perspective. As the method, a new macroergonomic compatibility questionnaire (MCQ) was developed and statistically validated, and 158 respondents at four manufacture companies were considered. Noise, lighting and temperature, humidity and air quality (THAQ) were used as independent variables and psychological characteristics and employees’ performance as dependent variables. To propose and test the hypothetical causal model of significant relationships among the variables, a data analysis was deployed. Results found that the macroergonomic compatibility of environmental elements presents significant direct effects on employees’ psychological characteristics and either direct or indirect effects on the employees’ performance. THAQ had the highest direct and total effects on psychological characteristics. Regarding the direct and total effects on employees’ performance, the psychological characteristics presented the highest effects, followed by THAQ conditions. These results may help measure and optimize manufacturing systems’ performance by enhancing their macroergonomic compatibility and quality of life at work of the employees. PMID:26742054

Structural Model for the Effects of Environmental Elements on the Psychological Characteristics and Performance of the Employees of Manufacturing Systems.

PubMed

Realyvásquez, Arturo; Maldonado-Macías, Aidé Aracely; García-Alcaraz, Jorge; Cortés-Robles, Guillermo; Blanco-Fernández, Julio

2016-01-05

This paper analyzes the effects of environmental elements on the psychological characteristics and performance of employees in manufacturing systems using structural equation modeling. Increasing the comprehension of these effects may help optimize manufacturing systems regarding their employees' psychological characteristics and performance from a macroergonomic perspective. As the method, a new macroergonomic compatibility questionnaire (MCQ) was developed and statistically validated, and 158 respondents at four manufacture companies were considered. Noise, lighting and temperature, humidity and air quality (THAQ) were used as independent variables and psychological characteristics and employees' performance as dependent variables. To propose and test the hypothetical causal model of significant relationships among the variables, a data analysis was deployed. Results found that the macroergonomic compatibility of environmental elements presents significant direct effects on employees' psychological characteristics and either direct or indirect effects on the employees' performance. THAQ had the highest direct and total effects on psychological characteristics. Regarding the direct and total effects on employees' performance, the psychological characteristics presented the highest effects, followed by THAQ conditions. These results may help measure and optimize manufacturing systems' performance by enhancing their macroergonomic compatibility and quality of life at work of the employees.

Arcjet starting reliability - A multistart test on hydrogen/nitrogen mixtures

NASA Technical Reports Server (NTRS)

Haag, Thomas W.; Curran, Frank M.

1987-01-01

An arcjet starting reliability test was performed to investigate one feasibility issue in the use of arcjets on board a satellite for north-south stationkeeping. A 1 kW arcjet was run on hydrogen/nitrogen gas mixtures simulating decomposed hydrazine. A pulse width modulated power supply with an integral high voltage starting pulser was used for arc ignition and steady-state operation. The test was performed in four phases in order to determine if starting characteristics changed as a result of long term thruster operation. More than 300 successful starts were accumulated over an operating time of 18 hr. Overall results indicate that there is a link between starting characteristics and long term thruster operation; however, the large number of starts had no effect on steady-state performance.

Arcjet starting reliability: A multistart test on hydrogen/nitrogen mixtures

NASA Technical Reports Server (NTRS)

Haag, Thomas W.; Curran, Frank M.

1987-01-01

An arcjet starting reliability test was performed to investigate one feasibility issue in the use of arcjets onboard a satellite for north-south stationkeeping. A 1 kW arcjet was run on hydrogen/nitrogen gas mixtures simulating decomposed hydrazine. A pulse width modulated power supply with an integral high voltage starting pulser was used for arc ignition and steady-state operation. The test was performed in four phases in order to determine if starting characteristics changed as a result of long term thruster operation. More than 300 successful starts were accumulated over an operating time of 18 hrs. Overall results indicate that there is a link between starting characteristics and long term thruster operation; however, the large number of starts had no effect on steady-state performance.

Experimental and analytical comparison of flowfields in a 110 N (25 lbf) H2/O2 rocket

NASA Technical Reports Server (NTRS)

Reed, Brian D.; Penko, Paul F.; Schneider, Steven J.; Kim, Suk C.

1991-01-01

A gaseous hydrogen/gaseous oxygen 110 N (25 lbf) rocket was examined through the RPLUS code using the full Navier-Stokes equations with finite rate chemistry. Performance tests were conducted on the rocket in an altitude test facility. Preliminary parametric analyses were performed for a range of mixture ratios and fuel film cooling pcts. It is shown that the computed values of specific impulse and characteristic exhaust velocity follow the trend of the experimental data. Specific impulse computed by the code is lower than the comparable test values by about two to three percent. The computed characteristic exhaust velocity values are lower than the comparable test values by three to four pct. Thrust coefficients computed by the code are found to be within two pct. of the measured values. It is concluded that the discrepancy between computed and experimental performance values could not be attributed to experimental uncertainty.

Metering Characteristics of Carburetors

NASA Technical Reports Server (NTRS)

Tice, Percival S; Dickinson, H C

1919-01-01

Report presents the results of an extensive experimental investigation of the performance of different types of carburetors as effecting the maintenance under all conditions of correct ratio between the weights of fuel and air. It also gives a description of the Bureau of Standards carburetor test plant, test equipment and measuring instruments used to determine the metering characteristics of carburetors.

Do Associations Between Perceived Environmental and Individual Characteristics and Walking Limitations Depend on Lower Extremity Performance Level?

PubMed

Sakari, Ritva; Rantakokko, Merja; Portegijs, Erja; Iwarsson, Susanne; Sipilä, Sarianna; Viljanen, Anne; Rantanen, Taina

2017-06-01

The aim of this study was to analyze whether the associations between perceived environmental and individual characteristics and perceived walking limitations in older people differ between those with intact and those with poorer lower extremity performance. Persons aged 75 to 90 ( N = 834) participated in interviews and performance tests in their homes. Standard questionnaires were used to obtain walking difficulties; environmental barriers to and, facilitators of, mobility; and perceived individual hindrances to outdoor mobility. Lower extremity performance was tested using Short Physical Performance Battery (SPPB). Among those with poorer lower extremity performance, the likelihood for advanced walking limitations was, in particular, related to perceived poor safety in the environment, and among those with intact performance to perceived social issues, such as lack of company, as well as to long distances. The environmental correlates of walking limitations seem to depend on the level of lower extremity performance.

Video Games as Psychological Tests.

ERIC Educational Resources Information Center

Jones, Marshall B.

1984-01-01

Briefly describes the characteristics of video games and discusses some advantages and disadvantages of their use to measure individual abilities. Relevant research is cited in the areas of stabilization with practice, predictive testing, performance testing, testing under extreme conditions, testing brain-injured persons, and differential…

Relationship between performance variables and baseball ability in youth baseball players.

PubMed

Nakata, Hiroki; Nagami, Tomoyuki; Higuchi, Takatoshi; Sakamoto, Kiwako; Kanosue, Kazuyuki

2013-10-01

The present study investigated the relationship of performance variables and anthropometric measurements on baseball ability in 164 youth baseball players (age: 6.4-15.7 years). To evaluate their baseball performance, ball speeds in pitching and batting were recorded and kinetic energies of the pitched and hit balls were calculated. To record anthropometric and physical fitness characteristics, height and weight were measured and a battery of physical fitness tests covering standing long jump, side steps, sit-ups, 10-m sprint, trunk flexion, back strength, and grip strengths of both hands were conducted. The results of a multiple regression analysis revealed several significant predictors: age, body mass index (BMI), standing long jump, 10-m sprint, and grip strength for pitched ball kinetic energy and age, BMI, standing long jump, and back strength for hit ball kinetic energy. This study provides scientific evidence that relates certain specific physical performance tests and body characteristics with high achievement in the actual performance of pitching and batting. Youth players, their parents, coaches, and trainers would benefit by addressing these characteristics when planning training programs to improve the baseball performance of youth players.

Performance of alkaline battery cells used in emergency locator transmitters

NASA Technical Reports Server (NTRS)

Haynes, G. A.; Sokol, S.; Motley, W. R., III; Mcclelland, E. L.

1984-01-01

The characteristics of battery power supplies for emergency locator transmitters (ELT's) were investigated by testing alkaline zinc/manganese dioxide cells of the type typically used in ELT's. Cells from four manufacturers were tested. The cells were subjected to simulated environmental and load conditions representative of those required for survival and operation. Battery cell characteristics that may contribute to ELT malfunctions and limitations were evaluated. Experimental results from the battery cell study are discussed, and an evaluation of ELT performance while operating under a representative worst-case environmental condition is presented.

Free-flight investigation of the stability and control characteristics of a STOL model with an externally blown jet flap

NASA Technical Reports Server (NTRS)

Parlett, L. P.; Emerling, S. J.; Phelps, A. E., III

1974-01-01

The stability and control characteristics of a four-engine turbofan STOL transport model having an externally blown jet flap have been investigated by means of the flying-model technique in the Langley full-scale tunnel. The flight characteristics of the model were investigated under conditions of symmetric and asymmetric (one engine inoperative) thrust at lift coefficients up to 9.5 and 5.5, respectively. Static characteristics were studied by conventional power-on force tests over the flight-test angle-of-attack range including the stall. In addition to these tests, dynamic longitudinal and lateral stability calculations were performed for comparison with the flight-test results and for use in correlating the model results with STOL handling-qualities criteria.

49 CFR Appendix B to Part 238 - Test Methods and Performance Criteria for the Flammability and Smoke Emission Characteristics of...

Code of Federal Regulations, 2010 CFR

2010-10-01

..., etc.) shall be designed against acting as passageways for fire and smoke and representative... structural flooring assembly to perform as a barrier against under-vehicle fires. The fire resistance period... Flammability and Smoke Emission Characteristics of Materials Used in Passenger Cars and Locomotive Cabs B...

Inlet Performance Characteristics from Wind-Tunnel Tests of a 0.10-Scale Air-Induction System Model of the YF-108A Airplane at Mach Numbers of 2.50, 2.76, and 3.00

NASA Technical Reports Server (NTRS)

Blackaby, James R.; Lyman, E. Gene; Altermann, John A., III

1959-01-01

Inlet-performance and external-drag-coefficient characteristics are presented without analysis. Effects are shown of variations of fuselage boundary-layer diverter profile, bleed-surface porosity, bleed-exit area, and inlet ramp, and lip angle.

Physical performance characteristics of high-level female soccer players 12-21 years of age.

PubMed

Vescovi, J D; Rupf, R; Brown, T D; Marques, M C

2011-10-01

Performance assessment has become an invaluable component of monitoring player development and within talent identification programs in soccer, yet limited performance data are available for female soccer players across a wide age range. The aim of this study was to describe the physical performance characteristics of female soccer players ranging in age from 12 to 21 years. High-level female soccer players (n=414) were evaluated on linear sprinting (36.6 m with 9.1 m splits), countermovement jump (CMJ), and two agility tests. Separate one-way ANOVAs were used to compare performance characteristics between (1) each year of chronological age and (2) three age groups: 12-13 years, n=78, 14-17 years, n=223, and 18-21 years, n=113. Mean linear sprint speed over 9.1 m was similar across all chronological ages, however sprint speed over the final 9.1 m, CMJ height and agility scores improved until approximately 15-16 years. Outcomes from the group data indicated better performance on all tests for the 14-17-year-old group compared with the 12-13-year-old group. Additionally, sprint speed on the second and fourth 9.1 m splits and 36.6 m sprint speed as well as performance on the Illinois agility test was better in the 18-21-year-old group compared with the 14-17-year-old group. The findings from this study indicate that marked improvements of high intensity short duration work occur up until 15-16 years. Smaller gains in performance were observed beyond 16 years of age as evidenced by better performance on 36.6 m sprint speed, several sprint splits and the Illinois agility test in the college aged players (i.e., 18-21-year-old group). © 2010 John Wiley & Sons A/S.

RELATIONSHIP BETWEEN ISOKINETIC KNEE STRENGTH AND JUMP CHARACTERISTICS FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION.

PubMed

Laudner, Kevin; Evans, Daniel; Wong, Regan; Allen, Aaron; Kirsch, Tom; Long, Brian; Meister, Keith

2015-06-01

Clinicians are often challenged when making return-to-play decisions following anterior cruciate ligament reconstruction (ACL-R). Isokinetic strength and jump performance testing are common tools used to make this decision. Unfortunately, vertical jump performance standards have not been clearly established and many clinicians do not have access to isokinetic testing equipment. To establish normative jump and strength characteristics in ACL-R patients cleared by an orthopedic physician to return-to-play and to determine if relationships exist between knee isokinetic strength measurements and jump characteristics described using an electronic jump map system. Descriptive laboratory study. Thirty-three ACL-R patients who had been cleared to return to athletic competition participated in this study. Twenty-six of these ACL-R participants were also matched to 26 asymptomatic athletes based on sex, limb, height, and mass to determine isokinetic strength and jump characteristic differences between groups. Jump tests consisted of single leg vertical, double leg vertical, and a 4-jump single leg vertical jump assessed using an electronic jump mat system. Independent t-tests were used to determine differences between groups and multiple regression analyses were used to identify any relationships between jump performance and knee strength (p<0.05). The ACL-R group had lower vertical jump capabilities and some bilateral knee strength deficiencies compared to the matched control group. The ACL-R group also showed several moderate-to-strong positive relationships for both knee extension and flexion strength with several jump performance characteristics, such as single and double leg vertical jump height. The current results indicate that ACL-R patients present with several knee strength and vertical jump differences compared to a matched control group at the time of return-to-play. Also, ACL-R patient's performance on an electronic jump mat system is strongly related to isokinetic knee strength measures. 2b.

Anthropometric and physical performance characteristics of top-elite, elite and non-elite youth female team handball players.

PubMed

Moss, Samantha Louise; McWhannell, Nicola; Michalsik, Lars Bojsen; Twist, Craig

2015-01-01

In order to maximise the potential for success, developing nations need to produce superior systems to identify and develop talent, which requires comprehensive and up-to-date values on elite players. This study examined the anthropometric and physical characteristics of youth female team handball players (16.07 ± 1.30 years) in non-elite (n = 47), elite (n = 37) and top-elite players (n = 29). Anthropometric profiling included sum of eight skinfolds, body mass, stature, girths, breadths and somatotype. Performance tests included 20 m sprint, counter-movement jump, throwing velocity, repeated shuttle sprint and jump ability test, and Yo-Yo Intermittent Recovery Test Level 1. Youth top-elite players had greater body mass, lean mass, stature, limb girths and breadths than elite and non-elite players, while only stature and flexed arm were higher in elite compared to non-elite players (all P < 0.05). Sum of skinfolds and waist-to-hip ratio were similar between groups (P > 0.05). Top-elite performed better in most performance tests compared to both elite and non-elite players (P < 0.05), although maximal and repeated 10 m sprints were similar between playing standards (P > 0.05). Elite outperformed non-elite players only in throwing velocity. The findings reveal that non-elite players compare unfavourably to top-elite international European players in many anthropometric and performance characteristics, and differ in a few characteristics compared to elite European club team players. This study is useful for emerging team handball nations in improving talent identification processes.

Experimental test program for evaluation of solid lubricant coating as applied to compliant foil gas bearings to 315 deg C

NASA Technical Reports Server (NTRS)

Wagner, R. C.

1985-01-01

An experimental apparatus and test procedure was developed to compare the performance of two solid lubricant coatings for air lubricated compliant foil gas bearings in the temperature range of 25 to 315 C. Polyimide bonded additive (SBGC) were tested extensively for durability and frictional characteristics. A partial arc bearing constructed of Inconel X-750 was coated on the bore with one of these coatings. The foil was subjected to repeated start/stop cycles. Performance comparisons reveal that although both coatings survive thousands of start/stop cycles, only the PBGF coated bearing achieves the specified 9000 start/stops. There is enough wear on the SBGC coated bearing to warrant termination of the test prior to 9000 start/stop cycles due to coating failure. The frictional characteristics of the PBGF are better at the elevated temperatures than at lower temperatures; a marked increase in sliding friction occurs as the temperature decreases. The SBGC maintains relatively constant frictional characteristics independent of operating temperature.

Spread Spectrum Receiver Electromagnetic Interference (EMI) Test Guide

NASA Technical Reports Server (NTRS)

Wheeler, Mark L.

1998-01-01

This program consisted of: (1) a study to define appropriate EMI test guidelines and test methods for direct sequence (DS) spread spectrum receivers; and (2) preparation of a written test guide to document the recommended test methods. The scope of this test guide includes: (1) a discussion of generic DS receiver performance characteristics; (2) a summary of S-band TDRSS receiver operation; (3) a discussion of DS receiver EMI susceptibility mechanisms and characteristics; (4) a summary of military standard test guidelines; (5) recommended test approach and methods; and (6) general conclusions and recommendations for future studies in the area of spread spectrum receiver testing.

The development of an augmentor wing jet STOL research aircraft (modified C-8A). Volume 2: Analysis of contractor's flight test

NASA Technical Reports Server (NTRS)

Skavdahl, H.; Patterson, D. H.

1972-01-01

The initial flight test phase of the modified C-8A airplane was conducted. The primary objective of the testing was to establish the basic airworthiness of the research vehicle. This included verification of the structural design and evaluation of the aircraft's systems. Only a minimum amount of performance testing was scheduled; this has been used to provide a preliminary indication of the airplane's performance and flight characteristics for future flight planning. The testing included flutter and loads investigations up to the maximum design speed. The operational characteristics of all systems were assessed including hydraulics, environmental control system, air ducts, the vectoring conical nozzles, and the stability augmentation system (SAS). Approaches to stall were made at three primary flap settings: up, 30 deg and 65 deg, but full stalls were not scheduled. Minimum control speeds and maneuver margins were checked. All takeoffs and landings were conventional, and STOL performance was not scheduled during this phase of the evaluation.

A testing machine for dental air-turbine handpiece characteristics: free-running speed, stall torque, bearing resistance.

PubMed

Darvell, Brain W; Dyson, J E

2005-01-01

The measurement of performance characteristics of dental air turbine handpieces is of interest with respect to product comparisons, standards specifications and monitoring of bearing longevity in clinical service. Previously, however, bulky and expensive laboratory equipment was required. A portable test machine is described for determining three key characteristics of dental air-turbine handpieces: free-running speed, stall torque and bearing resistance. It relies on a special circuit design for performing a hardware integration of a force signal with respect to rotational position, independent of the rate at which the turbine is allowed to turn during both stall torque and bearing resistance measurements. Free-running speed without the introduction of any imbalance can be readily monitored. From the essential linear relationship between torque and speed, dynamic torque and, hence, power, can then be calculated. In order for these measurements to be performed routinely with the necessary precision of location on the test stage, a detailed procedure for ensuring proper gripping of the handpiece is described. The machine may be used to verify performance claims, standard compliance checks should this be established as appropriate, monitor deterioration with time and usage in the clinical environment and for laboratory investigation of design development.

Correction of Pressure Drop in Steam and Water System in Performance Test of Boiler

NASA Astrophysics Data System (ADS)

Liu, Jinglong; Zhao, Xianqiao; Hou, Fanjun; Wu, Xiaowu; Wang, Feng; Hu, Zhihong; Yang, Xinsen

2018-01-01

Steam and water pressure drop is one of the most important characteristics in the boiler performance test. As the measuring points are not in the guaranteed position and the test condition fluctuation exsits, the pressure drop test of steam and water system has the deviation of measuring point position and the deviation of test running parameter. In order to get accurate pressure drop of steam and water system, the corresponding correction should be carried out. This paper introduces the correction method of steam and water pressure drop in boiler performance test.

Experimental investigation of nonlinear characteristics of a smart fluid damper

NASA Astrophysics Data System (ADS)

Rahman, Mahmudur; Ong, Zhi Chao; Chong, Wen Tong; Julai, Sabariah; Ahamed, Raju

2018-05-01

Smart fluids, known as smart material, are used to form controllable dampers in vibration control applications. Magnetorheological(MR) fluid damper is a well-known smart fluid damper which has a reputation to provide high damping force with low-power input. However, the force/velocity of the MR damper is significantly nonlinear and proper characteristic analysis are required to be studied for optimal implementation in structural vibration control. In this study, an experimental investigation is carried out to test the damping characteristics of MR damper. Dynamic testing is performed with a long-stroke MR damper model no RD-80410-1 from Lord corporation on a universal testing machine(UTM). The force responses of MR damper are measured under different stroke lengths, velocities and current inputs and their performances are analyzed. This study will play a key role to implement MR damper in many structural vibration control applications.

Solar thermal upper stage technology demonstrator liquid hydrogen storage and feed system test program

NASA Astrophysics Data System (ADS)

Cady, E. C.

1997-01-01

The Solar Thermal Upper Stage Technology Demonstrator (STUSTD) Liquid Hydrogen Storage and Feed System (LHSFS) Test Program is described. The test program consists of two principal phases. First, an engineering characterization phase includes tests performed to demonstrate and understand the expected tank performance. This includes fill and drain; baseline heat leak; active Thermodynamic Vent System (TVS); and flow tests. After the LHSFS performance is understood and performance characteristics are determined, a 30 day mission simulation test will be conducted. This test will simulate a 30 day transfer mission from low earth orbit (LEO) to geosynchronous equatorial orbit (GEO). Mission performance predictions, based on the results of the engineering characterization tests, will be used to correlate the results of the 30 day mission simulation.

Effects of Pump-turbine S-shaped Characteristics on Transient Behaviours: Experimental Investigation

NASA Astrophysics Data System (ADS)

Zeng, Wei; Yang, Jiandong; Hu, Jinhong; Tang, Renbo

2017-05-01

A pumped storage stations model was set up and introduced in the previous paper. In the model station, the S-shaped characteristic curves was measured at the load rejection condition with the guide vanes stalling. Load rejection tests where guide-vane closed linearly were performed to validate the effect of the S-shaped characteristics on hydraulic transients. Load rejection experiments with different guide vane closing schemes were also performed to determine a suitable scheme considering the S-shaped characteristics. The condition of one pump turbine rejecting its load after another defined as one-after-another (OAA) load rejection was performed to validate the possibility of S-induced extreme draft tube pressure.

Evaluation of the Field Performance of ImmunoCard STAT!® Rapid Diagnostic Test for Rotavirus in Dadaab Refugee Camp and at the Kenya–Somalia Border

PubMed Central

Ope, Maurice; Nyoka, Raymond; Unshur, Ahmed; Oyier, Fredrick O.; Mowlid, Shafe A.; Owino, Brian; Ochieng, Steve B.; Okello, Charles I.; Montgomery, Joel M.; Wagacha, Burton; Galev, Aleksandar; Abdow, Abdikadir; Esona, Mathew D.; Tate, Jacqueline; Fitter, David; Cookson, Susan T.; Arunmozhi, Balajee; Marano, Nina

2017-01-01

Rotavirus commonly causes diarrhea in children, leading to hospitalization and even death. Rapid diagnostic tests are feasible alternatives for determining rotavirus outbreaks in refugee camps that have inadequate laboratory capacity. We evaluated the field performance of ImmunoCard STAT!® Rotavirus (ICS-RV) in Dadaab Refugee Camp and at the Kenya–Somalia border. From May to December 2014, we prospectively enrolled children aged < 5 years hospitalized with acute diarrhea, defined as ≥ 3 episodes of loose stool in 24 hours for < 7 days. Stool samples were collected and tested by trained surveillance clerks using ICS-RV per manufacturer's instructions. The field performance characteristics of ICS-RV were evaluated against the gold standard test, Premier™ Rotaclone® enzyme immunoassay. The operational characteristics were evaluated using World Health Organization (WHO) ASSURED criteria to determine whether ICS-RV is appropriate as a point-of-care test by administering a standard questionnaire and observing surveillance clerks performing the test. We enrolled 213 patients with a median age of 10 months (range = 1–48); 58.2% were male. A total of 71 (33.3%) and 60 (28.2%) patients tested positive for rotavirus infection by immunoassay and ICS-RV, respectively. The sensitivity, specificity, and positive and negative predictive values of ICS-RV compared with the immunoassay were 83.1% (95% confidence interval [CI] = 72.3–91.0), 99.3% (95% CI = 96.1–100), 98.3% (95% CI = 91.1–100), and 92.1% (95% CI = 86.6–95.5), respectively. The ICS-RV fulfilled the WHO ASSURED criteria for point-of-care testing. ICS-RV is a field-ready point-of-care test with good field performance and operational characteristics. It can be useful in determining rotavirus outbreaks in resource-limited settings. PMID:28719278

Evaluation of the Field Performance of ImmunoCard STAT!® Rapid Diagnostic Test for Rotavirus in Dadaab Refugee Camp and at the Kenya-Somalia Border.

PubMed

Ope, Maurice; Nyoka, Raymond; Unshur, Ahmed; Oyier, Fredrick O; Mowlid, Shafe A; Owino, Brian; Ochieng, Steve B; Okello, Charles I; Montgomery, Joel M; Wagacha, Burton; Galev, Aleksandar; Abdow, Abdikadir; Esona, Mathew D; Tate, Jacqueline; Fitter, David; Cookson, Susan T; Arunmozhi, Balajee; Marano, Nina

2017-06-01

AbstractRotavirus commonly causes diarrhea in children, leading to hospitalization and even death. Rapid diagnostic tests are feasible alternatives for determining rotavirus outbreaks in refugee camps that have inadequate laboratory capacity. We evaluated the field performance of ImmunoCard STAT! ® Rotavirus (ICS-RV) in Dadaab Refugee Camp and at the Kenya-Somalia border. From May to December 2014, we prospectively enrolled children aged < 5 years hospitalized with acute diarrhea, defined as ≥ 3 episodes of loose stool in 24 hours for < 7 days. Stool samples were collected and tested by trained surveillance clerks using ICS-RV per manufacturer's instructions. The field performance characteristics of ICS-RV were evaluated against the gold standard test, Premier ™ Rotaclone ® enzyme immunoassay. The operational characteristics were evaluated using World Health Organization (WHO) ASSURED criteria to determine whether ICS-RV is appropriate as a point-of-care test by administering a standard questionnaire and observing surveillance clerks performing the test. We enrolled 213 patients with a median age of 10 months (range = 1-48); 58.2% were male. A total of 71 (33.3%) and 60 (28.2%) patients tested positive for rotavirus infection by immunoassay and ICS-RV, respectively. The sensitivity, specificity, and positive and negative predictive values of ICS-RV compared with the immunoassay were 83.1% (95% confidence interval [CI] = 72.3-91.0), 99.3% (95% CI = 96.1-100), 98.3% (95% CI = 91.1-100), and 92.1% (95% CI = 86.6-95.5), respectively. The ICS-RV fulfilled the WHO ASSURED criteria for point-of-care testing. ICS-RV is a field-ready point-of-care test with good field performance and operational characteristics. It can be useful in determining rotavirus outbreaks in resource-limited settings.

A high-performance liquid chromatography method for the serotonin release assay is equivalent to the radioactive method.

PubMed

Sono-Koree, N K; Crist, R A; Frank, E L; Rodgers, G M; Smock, K J

2016-02-01

The serotonin release assay (SRA) is considered the gold standard laboratory test for heparin-induced thrombocytopenia (HIT). The historic SRA method uses platelets loaded with radiolabeled serotonin to evaluate platelet activation by HIT immune complexes. However, a nonradioactive method is desirable. We report the performance characteristics of a high-performance liquid chromatography (HPLC) SRA method. We validated the performance characteristics of an HPLC-SRA method, including correlation with a reference laboratory using the radioactive method. Serotonin released from reagent platelets was quantified by HPLC using fluorescent detection. Results were expressed as % release and classified as positive, negative, or indeterminate based on previously published cutoffs. Serum samples from 250 subjects with suspected HIT were tested in the HPLC-SRA and with the radioactive method. Concordant classifications were observed in 230 samples (92%). Sera from 41 healthy individuals tested negative. Between-run imprecision studies showed standard deviation of <6 (% release) for positive, weak positive, and negative serum pools. Stability studies demonstrated stability after two freeze-thaw cycles or up to a week of refrigeration. The HPLC-SRA has robust performance characteristics, equivalent to the historic radioactive method, but avoids the complexities of working with radioactivity. © 2015 John Wiley & Sons Ltd.

Performance of a vane driven-gear pump

NASA Technical Reports Server (NTRS)

Heald, R H

1921-01-01

Given here are the results of a test conducted in a wind tunnel on the performance of a vane-driven gear pump used to pump gasoline upward into a small tank located within the upper wing from which it flows by gravity to the engine carburetor. Information is given on the efficiency of the pump, the head resistance of the vanes, the performance and characteristics of the unit with and without housing about the vanes, the pump performance when motor driven, and resistance and power characteristics.

Building an Evaluation Scale using Item Response Theory.

PubMed

Lalor, John P; Wu, Hao; Yu, Hong

2016-11-01

Evaluation of NLP methods requires testing against a previously vetted gold-standard test set and reporting standard metrics (accuracy/precision/recall/F1). The current assumption is that all items in a given test set are equal with regards to difficulty and discriminating power. We propose Item Response Theory (IRT) from psychometrics as an alternative means for gold-standard test-set generation and NLP system evaluation. IRT is able to describe characteristics of individual items - their difficulty and discriminating power - and can account for these characteristics in its estimation of human intelligence or ability for an NLP task. In this paper, we demonstrate IRT by generating a gold-standard test set for Recognizing Textual Entailment. By collecting a large number of human responses and fitting our IRT model, we show that our IRT model compares NLP systems with the performance in a human population and is able to provide more insight into system performance than standard evaluation metrics. We show that a high accuracy score does not always imply a high IRT score, which depends on the item characteristics and the response pattern.

Building an Evaluation Scale using Item Response Theory

PubMed Central

Lalor, John P.; Wu, Hao; Yu, Hong

2016-01-01

Evaluation of NLP methods requires testing against a previously vetted gold-standard test set and reporting standard metrics (accuracy/precision/recall/F1). The current assumption is that all items in a given test set are equal with regards to difficulty and discriminating power. We propose Item Response Theory (IRT) from psychometrics as an alternative means for gold-standard test-set generation and NLP system evaluation. IRT is able to describe characteristics of individual items - their difficulty and discriminating power - and can account for these characteristics in its estimation of human intelligence or ability for an NLP task. In this paper, we demonstrate IRT by generating a gold-standard test set for Recognizing Textual Entailment. By collecting a large number of human responses and fitting our IRT model, we show that our IRT model compares NLP systems with the performance in a human population and is able to provide more insight into system performance than standard evaluation metrics. We show that a high accuracy score does not always imply a high IRT score, which depends on the item characteristics and the response pattern.1 PMID:28004039

Effect of Background Pressure on the Plasma Oscillation Characteristics of the HiVHAc Hall Thruster

NASA Technical Reports Server (NTRS)

Huang, Wensheng; Kamhawi, Hani; Lobbia, Robert B.; Brown, Daniel L.

2014-01-01

During a component compatibility test of the NASA HiVHAc Hall thruster, a number of plasma diagnostics were implemented to study the effect of varying facility background pressure on thruster operation. These diagnostics characterized the thruster performance, the plume, and the plasma oscillations in the thruster. Thruster performance and plume characteristics as functions of background pressure were previously published. This paper focuses on changes in the plasma oscillation characteristics with changing background pressure. The diagnostics used to study plasma oscillations include a high-speed camera and a set of high-speed Langmuir probes. The results show a rise in the oscillation frequency of the "breathing" mode with rising background pressure, which is hypothesized to be due to a shortening acceleration/ionization zone. An attempt is made to apply a simplified ingestion model to the data. The combined results are used to estimate the maximum acceptable background pressure for performance and wear testing.

Analysis and correlation of the test data from an advanced technology rotor system

NASA Technical Reports Server (NTRS)

Jepson, D.; Moffitt, R.; Hilzinger, K.; Bissell, J.

1983-01-01

Comparisons were made of the performance and blade vibratory loads characteristics for an advanced rotor system as predicted by analysis and as measured in a 1/5 scale model wind tunnel test, a full scale model wind tunnel test and flight test. The accuracy with which the various tools available at the various stages in the design/development process (analysis, model test etc.) could predict final characteristics as measured on the aircraft was determined. The accuracy of the analyses in predicting the effects of systematic tip planform variations investigated in the full scale wind tunnel test was evaluated.

Gender Differences in Physical Performance Characteristics of Elite Surfers.

PubMed

Parsonage, Joanna R; Secomb, Josh L; Tran, Tai T; Farley, Oliver R L; Nimphius, Sophia; Lundgren, Lina; Sheppard, Jeremy M

2017-09-01

Parsonage, JR, Secomb, JL, Tran, TT, Farley, ORL, Nimphius, S, Lundgren, L, and Sheppard, JM. Gender differences in physical performance characteristics of elite surfers. J Strength Cond Res 31(9): 2417-2422, 2017-The purpose of this study was to describe and compare the gender differences in physical performance characteristics of elite surfers. Twenty competitive female surfers (CFS) and 20 competitive male surfers (CMS) performed a battery of physical performance tests: squat jump (SJ), isometric midthigh pull (IMTP), 15-m sprint paddle, and 400-m endurance paddle during a single testing session. All performance measures were significantly different between CFS and CMS (p < 0.01). Specifically, CMS produced greater peak force production (28.5%) and jumped higher (27.7%) in the SJ and produced greater normalized peak force during the IMTP (18.9%) compared with CFS. For paddling performance, CMS were faster over 5, 10, and 15 m (12.4%, 9.7%, and 10.9%), possessed a higher peak paddling velocity (11.3%), and recorded faster paddle times over 400 m (11.8%). The results of this study suggest that CMS exhibit superior physical performance characteristics than CFS, in relation to both the lower and upper body. Strength and conditioning practitioners should therefore implement a structured and periodized program to facilitate strength qualities that underpin surfing performance for all participants, but as highlighted in the current investigation, female surfers may have a greater window for adaptation and therefore vast benefit of targeting their underdeveloped physical qualities.

Research on simulation system with the wide range and high-precision laser energy characteristics

NASA Astrophysics Data System (ADS)

Dong, Ke-yan; Lou, Yan; He, Jing-yi; Tong, Shou-feng; Jiang, Hui-lin

2012-10-01

The Hardware-in-the-loop(HWIL) simulation test is one of the important parts for the development and performance testing of semi-active laser-guided weapons. In order to obtain accurate results, the confidence level of the target environment should be provided for a high-seeker during the HWIL simulation test of semi-active laser-guided weapons, and one of the important simulation parameters is the laser energy characteristic. In this paper, based on the semi-active laser-guided weapon guidance principles, an important parameter of simulation of confidence which affects energy characteristics in performance test of HWIL simulation was analyzed. According to the principle of receiving the same energy by using HWIL simulation and in practical application, HWIL energy characteristics simulation systems with the crystal absorption structure was designed. And on this basis, the problems of optimal design of the optical system were also analyzed. The measured results show that the dynamic attenuation range of the system energy is greater than 50dB, the dynamic attenuation stability is less than 5%, and the maximum energy changing rate driven by the servo motor is greater than 20dB/s.

Arcjet thruster research and technology

NASA Technical Reports Server (NTRS)

Makel, Darby B.; Cann, Gordon L.

1988-01-01

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

Investigation of the Effects of Facility Background Pressure on the Performance and Voltage-Current Characteristics of the High Voltage Hall Accelerator

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Huang, Wensheng; Haag, Thomas; Spektor, Rostislav

2014-01-01

The National Aeronautics and Space Administration (NASA) Science Mission Directorate In-Space Propulsion Technology office is sponsoring NASA Glenn Research Center to develop a 4 kW-class Hall thruster propulsion system for implementation in NASA science missions. A study was conducted to assess the impact of varying the facility background pressure on the High Voltage Hall Accelerator (HiVHAc) thruster performance and voltage-current characteristics. This present study evaluated the HiVHAc thruster performance in the lowest attainable background pressure condition at NASA GRC Vacuum Facility 5 to best simulate space-like conditions. Additional tests were performed at selected thruster operating conditions to investigate and elucidate the underlying physics that change during thruster operation at elevated facility background pressure. Tests were performed at background pressure conditions that are three and ten times higher than the lowest realized background pressure. Results indicated that the thruster discharge specific impulse and efficiency increased with elevated facility background pressure. The voltage-current profiles indicated a narrower stable operating region with increased background pressure. Experimental observations of the thruster operation indicated that increasing the facility background pressure shifted the ionization and acceleration zones upstream towards the thruster's anode. Future tests of the HiVHAc thruster are planned at background pressure conditions that are expected to be two to three times lower than what was achieved during this test campaign. These tests will not only assess the impact of reduced facility background pressure on thruster performance, voltage-current characteristics, and plume properties; but will also attempt to quantify the magnitude of the ionization and acceleration zones upstream shifting as a function of increased background pressure.

Physiological and physical characteristics of elite dragon boat paddlers.

PubMed

Ho, Sarah R; Smith, Richard M; Chapman, Philip G; Sinclair, Peter J; Funato, Kazuo

2013-01-01

The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.

Life prediction and reliability assessment of lithium secondary batteries

NASA Astrophysics Data System (ADS)

Eom, Seung-Wook; Kim, Min-Kyu; Kim, Ick-Jun; Moon, Seong-In; Sun, Yang-Kook; Kim, Hyun-Soo

Reliability assessment of lithium secondary batteries was mainly considered. Shape parameter (β) and scale parameter (η) were calculated from experimental data based on cycle life test. We also examined safety characteristics of lithium secondary batteries. As proposed by IEC 62133 (2002), we had performed all of the safety/abuse tests such as 'mechanical abuse tests', 'environmental abuse tests', 'electrical abuse tests'. This paper describes the cycle life of lithium secondary batteries, FMEA (failure modes and effects analysis) and the safety/abuse tests we had performed.

Analysis on weathering characteristics of volcanic rocks in Dokdo, Korea based on accelerated weatehring experiments

NASA Astrophysics Data System (ADS)

Woo, Ik; Song, Won-Kyong; Kim, Bok-Chul; Kang, Jinseok

2010-05-01

Dokdo consists of small volcanic islands located in the southern part of the East Sea. Accelerated weathering tests was performed to examine the physico-mechanical characteristics of volcanic rocks in Dokdo. Rock core specimens of trachyandesite, andesitic dyke and ash tuff were prepared, and double soxhlet extractors(DSE) and peristatic pumps were used for accelerating the weathering processes. The DSE was designed to perform cyclic leaching tests for rock core specimen using distilled water at seventy degrees centigrade. The core specimens which are classified according to pre-test weathering grades placed in the lower part of the DSE, and periodically exposed to hot distilled water at every ninety minutes. On the other hand the peristatic pumps were utilized to induce leaching by distilled or brine water at normal temperature. The physico-mechanical property changes including rock surface appearance, microscopic structure and rock strength were analyzed with the results obtained from both experiments performed for 120 days. The conducted research in this study have shown that the methodologies of artificial weathering experiments have strong capability to understand the weathering characteristics of the rocks effectively.

X-48B Flight Test Progress Overview

NASA Technical Reports Server (NTRS)

Risch, Timoth K.; Cosentino, Gary B.; Regan, Christopher D.; Kisska, Michael; Princen, Norman

2009-01-01

The results of a series of 39 flight tests of the X-48B Low Speed Vehicle (LSV) performed at the NASA Dryden Flight Research Center from July 2007 through December 2008 are reported here. The goal of these tests is to evaluate the aerodynamic and controls and dynamics performance of the subscale LSV aircraft, eventually leading to the development of a control system for a full-scale vehicle. The X-48B LSV is an 8.5%-scale aircraft of a potential, full-scale Blended Wing Body (BWB) type aircraft and is flown remotely from a ground control station using a computerized flight control system located onboard the aircraft. The flight tests were the first two phases of a planned three-phase research program aimed at ascertaining the flying characteristics of this type of aircraft. The two test phases reported here are: 1) envelope expansion, during which the basic flying characteristics of the airplane were examined, and 2) parameter identification, stalls, and engine-out testing, during which further information on the aircraft performance was obtained and the airplane was tested to the limits of controlled flight. The third phase, departure limiter assaults, has yet to be performed. Flight tests in two different wing leading edge configurations (slats extended and slats retracted) as well as three weight and three center of gravity positions were conducted during each phase. Data gathered in the test program included measured airplane performance parameters such as speed, acceleration, and control surface deflections along with qualitative flying evaluations obtained from pilot and crew observations. Flight tests performed to-date indicate the aircraft exhibits good handling qualities and performance, consistent with pre-flight simulations.

Screening for cognitive dysfunction in Huntington's disease with the clock drawing test.

PubMed

Terwindt, Paul W; Hubers, Anna A M; Giltay, Erik J; van der Mast, Rose C; van Duijn, Erik

2016-09-01

The aim of the study is to investigate the performance of the clock drawing test as a screening tool for cognitive impairment in Huntington's disease (HD) mutation carriers. The performance of the clock drawing test was assessed in 65 mutation carriers using the Shulman and the Freund scoring systems. The mini-mental state examination, the Symbol Digit Modalities Test, the Verbal Fluency Test, and the Stroop tests were used as comparisons for the evaluation of cognitive functioning. Correlations of the clock drawing test with various cognitive tests (convergent validity), neuropsychiatric characteristics (divergent validity) and clinical characteristics were analysed using the Spearman's rank correlation coefficient. Receiver-operator characteristic analyses were performed for the clock drawing test against both the mini-mental state examination and against a composite variable for executive cognitive functioning to assess optimal cut-off scores. Inter-rater reliability was high for both the Shulman and Freund scoring systems (ICC = 0.95 and ICC = 0.90 respectively). The clock drawing tests showed moderate to high correlations with the composite variable for executive cognitive functioning (mean ρ = 0.75) and weaker correlations with the mini-mental state examination (mean ρ = 0.62). Mean sensitivity of the clock drawing tests was 0.82 and mean specificity was 0.79, whereas the mean positive predictive value was 0.66 and the mean negative predictive value was 0.87. The clock drawing test is a suitable screening instrument for cognitive dysfunction in HD, because it was shown to be accurate, particularly so with respect to executive cognitive functioning, and is easy and quick to use. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The association between physical characteristics of the ankle joint and the mobility performance in elderly people with type 2 diabetes mellitus.

PubMed

Ng, Thomas Ka-Wai; Lo, Sing-Kai; Cheing, Gladys Lai-Ying

2014-01-01

Previous studies showed that older adults with diabetes have a worse mobility performance as compared with those without diabetes. Studies also demonstrated that older adults with diabetes have weakened ankle muscle strength, reduced joint range in ankle dorsiflexion and worsened ankle joint proprioception as compared with control population. The purpose of the present study was to examine the relationship between the physical characteristics of the ankle joint and the mobility performance in older adults with type 2 diabetes. Older adults with type 2 diabetes (n=85) were recruited, and Timed Up and Go test (TUG) for mobility assessment was performed. Active ankle joint repositioning test was used for assessing the ankle joint proprioception sense; peak torque of ankle dorsiflexors and plantar flexors were tested by using a Cybex Norm dynamometer, and weight-bearing lunge test (WBLT) was used for assessing the stiffness of ankle dorsiflexion. Our results showed that age, body mass index (BMI), normalized peak torque of plantar flexors and dorsiflexors, active ankle joint repositioning test errors and the WBLT distance were significantly correlated with the TUG (all p<0.001). These ankle characteristics, together with the demographic data of the subjects, contributed 59.9% of the variance in the TUG by multiple regression analysis. Body mass, ankle plantar flexors strength and ankle joint proprioception are important factors contributing to the physical mobility of the older adults with type 2 diabetes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Thermal performance of MSFC hot air collectors under natural and simulated conditions

NASA Technical Reports Server (NTRS)

Shih, K., Sr.

1977-01-01

The procedures used and the results obtained from an evaluation test program conducted to determine the thermal performance and structural characteristics of selected MSFC--designed hot air collectors under both real and simulated environmental conditions are described. Five collectors were tested in the three phased program. A series of outdoor tests were conducted to determine stagnation temperatures on a typical bright day and to determine each collector's ability to withstand these temperatures. Two of the collectors experienced structural deformation sufficient to eliminate them from the remainder of the test program. A series of outdoor tests to evaluate the thermal performance of collector S/N 10 under certain test conditions were performed followed by a series of indoor tests to evaluate the thermal performance of the collector under closely controlled simulated conditions.

Development of an analytical method to predict helicopter main rotor performance in icing conditions

NASA Technical Reports Server (NTRS)

Britton, Randall K.

1992-01-01

Historically, certification of a helicopter for flight into known icing conditions was a problem. This is because of the current emphasis on flight testing for verification of system performance. Flight testing in icing conditions is difficult because, in addition to being dangerous and expensive, many times conditions which are sought after cannot be readily found in nature. The problem is compounded for helicopters because of their small range in comparison to many fixed wing aircraft. Thus, helicopters are forced to wait for conditions to occur in a certain region rather than seeking them out. These and other drawbacks to flight testing prompted extreme interest in developing validated alternatives to flight testing. One such alternative is theoretical prediction. It is desirable to have the ability to predict how a helicopter will perform when subjected to icing conditions. Herein, calculations are restricted to the main rotor, and are illustrated. The computational tool used to obtain performance is the lifting line analysis of B65. B65 incorporates experimental data into data banks in order to determine the section lift, drag, and moment characteristics of various airfoils at different Mach numbers and angles of attack. The local flow angle is calculated at user specified radial locations. This flow angle, along with the local Mach number is then cross referenced with the airfoil tables to obtain the local section characteristics. The local characteristics are then integrated together to obtain the entire rotor attributes. Once the clean performance is known, characterization of the type and shape of ice which accretes on the rotor blades is obtained using the analysis of LEWICE. The Interactive Boundary Layer (IBL) method then calculates the 2-D characteristics of the iced airfoil for input into the airfoil data bank of B65. Calculations are restricted to natural ice shedding and it is assumed that no de-icing takes place. Once the new lift, drag, and moment characteristics are known for the entire blade radius, this information is fed into B65, where the iced performance is then calculated.

Monothermal caloric screening test performance: a relative operating characteristic curve analysis.

PubMed

Murnane, Owen D; Akin, Faith W; Lynn, Susan G; Cyr, David G

2009-06-01

The objective of the present study was to evaluate the performance of the monothermal caloric screening test in a large sample of patients. A retrospective analysis of the medical records of 1002 consecutive patients who had undergone vestibular assessment at the Mayo Clinic during the years 1989 and 1990 was conducted. Patients with incomplete alternate binaural bithermal (ABB) caloric testing, congenital or periodic alternating nystagmus, or bilateral vestibular loss were excluded from the study. Clinical decision theory analyses (relative operating characteristic curves) were used to determine the accuracy with which the monothermal warm (MWST) and monothermal cool (MCST) caloric screening tests predicted the results of the ABB caloric test. Cumulative distributions were constructed as a function of the cutoff points for monothermal interear difference (IED) to select the cutoff point associated with any combination of true-positive and false-positive rates. Both MWST and MCST performed well above chance level. The test performance for the MWST was significantly better than that of the MCST for three of the four ABB gold standards. A 10% IED cutoff point for the MWST yielded a false-negative rate of either 1% (UW >or=25%) or 3% (UW >or=20%). The use of a 10% IED (UW >or=25%) for the MWST would have resulted in a 40% reduction (N = 294) in the number of ABB caloric tests performed on patients without a unilateral weakness. The results of this study indicated that the MWST decreases test time without sacrificing the sensitivity of the ABB caloric test.

Comparison of Three Screening Test Kits for G6PD Enzyme Deficiency: Implications for Its Use in the Radical Cure of Vivax Malaria in Remote and Resource-Poor Areas in the Philippines.

PubMed

Espino, Fe Esperanza; Bibit, Jo-Anne; Sornillo, Johanna Beulah; Tan, Alvin; von Seidlein, Lorenz; Ley, Benedikt

2016-01-01

We evaluated a battery of Glucose-6-Phosphate Dehydrogenase diagnostic point-of-care tests (PoC) to assess the most suitable product in terms of performance and operational characteristics for remote areas. Samples were collected in Puerto Princesa City, Palawan, Philippines and tested for G6PD deficiency with a fluorescent spot test (FST; Procedure 203, Trinity Biotech, Ireland), the semiquantitative WST8/1-methoxy PMS (WST; Dojindo, Japan) and the Carestart G6PD Rapid Diagnostic Test (CSG; AccessBio, USA). Results were compared to spectrophotometry (Procedure 345, Trinity Biotech, Ireland). Sensitivity and specificity were calculated for each test with cut-off activities of 10%, 20%, 30% and 60% of the adjusted male median. The adjusted male median was 270.5 IU/10(12) RBC. FST and WST were tested on 621 capillary blood samples, the CSG was tested on venous and capillary blood on 302 samples. At 30% G6PD activity, sensitivity for the FST was between 87.7% (95%CI: 76.8% to 93.9%) and 96.5% (95%CI: 87.9% to 99.5%) depending on definition of intermediate results; the WST was 84.2% (95%CI: 72.1% to 92.5%); and the CSG was between 68.8% (95%CI: 41.3% to 89.0%) and 93.8% (95%CI: 69.8% to 99.8%) when the test was performed on capillary or venous blood respectively. Sensitivity of FST and CSG (tested with venous blood) were comparable (p>0.05). The analysis of venous blood samples by the CSG yielded significantly higher results than FST and CSG performed on capillary blood (p<0.05). Sensitivity of the CSG varied depending on source of blood used (p<0.05). The operational characteristics of the CSG were superior to all other test formats. Performance and operational characteristics of the CSG performed on venous blood suggest the test to be a good alternative to the FST.

Comparison of Three Screening Test Kits for G6PD Enzyme Deficiency: Implications for Its Use in the Radical Cure of Vivax Malaria in Remote and Resource-Poor Areas in the Philippines

PubMed Central

Espino, Fe Esperanza; Sornillo, Johanna Beulah; Tan, Alvin; von Seidlein, Lorenz

2016-01-01

Objective We evaluated a battery of Glucose-6-Phosphate Dehydrogenase diagnostic point-of-care tests (PoC) to assess the most suitable product in terms of performance and operational characteristics for remote areas. Methods Samples were collected in Puerto Princesa City, Palawan, Philippines and tested for G6PD deficiency with a fluorescent spot test (FST; Procedure 203, Trinity Biotech, Ireland), the semiquantitative WST8/1-methoxy PMS (WST; Dojindo, Japan) and the Carestart G6PD Rapid Diagnostic Test (CSG; AccessBio, USA). Results were compared to spectrophotometry (Procedure 345, Trinity Biotech, Ireland). Sensitivity and specificity were calculated for each test with cut-off activities of 10%, 20%, 30% and 60% of the adjusted male median. Results The adjusted male median was 270.5 IU/1012 RBC. FST and WST were tested on 621 capillary blood samples, the CSG was tested on venous and capillary blood on 302 samples. At 30% G6PD activity, sensitivity for the FST was between 87.7% (95%CI: 76.8% to 93.9%) and 96.5% (95%CI: 87.9% to 99.5%) depending on definition of intermediate results; the WST was 84.2% (95%CI: 72.1% to 92.5%); and the CSG was between 68.8% (95%CI: 41.3% to 89.0%) and 93.8% (95%CI: 69.8% to 99.8%) when the test was performed on capillary or venous blood respectively. Sensitivity of FST and CSG (tested with venous blood) were comparable (p>0.05). The analysis of venous blood samples by the CSG yielded significantly higher results than FST and CSG performed on capillary blood (p<0.05). Sensitivity of the CSG varied depending on source of blood used (p<0.05). Conclusion The operational characteristics of the CSG were superior to all other test formats. Performance and operational characteristics of the CSG performed on venous blood suggest the test to be a good alternative to the FST. PMID:26849445

Design and demonstrate the performance of cryogenic components representative of space vehicles: Start basket liquid acquisition device performance analysis

NASA Technical Reports Server (NTRS)

1987-01-01

The objective was to design, fabricate and test an integrated cryogenic test article incorporating both fluid and thermal propellant management subsystems. A 2.2 m (87 in) diameter aluminum test tank was outfitted with multilayer insulation, helium purge system, low-conductive tank supports, thermodynamic vent system, liquid acquisition device and immersed outflow pump. Tests and analysis performed on the start basket liquid acquisition device and studies of the liquid retention characteristics of fine mesh screens are discussed.

Draft Plan to Develop Non-Intrusive Load Monitoring Test Protocols

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

Mayhorn, Ebony T.; Sullivan, Greg P.; Petersen, Joseph M.

2015-09-29

This document presents a Draft Plan proposed to develop a common test protocol that can be used to evaluate the performance requirements of Non-Intrusive Load Monitoring. Development on the test protocol will be focused on providing a consistent method that can be used to quantify and compare the performance characteristics of NILM products. Elements of the protocols include specifications for appliances to be used, metrics, instrumentation, and a procedure to simulate appliance behavior during tests. In addition, three priority use cases for NILM will be identified and their performance requirements will specified.

Field evaluation of the 22 rapid diagnostic tests for community management of malaria with artemisinin combination therapy in Cameroon.

PubMed

Ali, Innocent M; Bigoga, Jude D; Forsah, Dorothy A; Cho-Ngwa, Fidelis; Tchinda, Vivian; Moor, Vicky Ama; Fogako, Josephine; Nyongalema, Philomena; Nkoa, Theresa; Same-Ekobo, Albert; Mbede, Joseph; Fondjo, Etienne; Mbacham, Wilfred F; Leke, Rose G F

2016-01-20

All suspected cases of malaria should receive a diagnostic test prior to treatment with artemisinin-based combinations based on the new WHO malaria treatment guidelines. This study compared the accuracy and some operational characteristics of 22 different immunochromatographic antigen capture point-of- malaria tests (RDTs) in Cameroon to inform test procurement prior to deployment of artemisinin-based combinations for malaria treatment. One hundred human blood samples (50 positive and 50 negative) collected from consenting febrile patients in two health centres at Yaoundé were used for evaluation of the 22 RDTs categorized as "Pf Only" (9) or "Pf + PAN" (13) based on parasite antigen captured [histidine rich protein II (HRP2) or lactate dehydrogenase (pLDH) or aldolase]. RDTs were coded to blind technicians performing the tests. The sensitivity, specificity, and predictive values of the positive and negative tests (PPV and NPV) as well as the likelihood ratios were assessed. The reliability and some operational characteristics were determined as the mean values from two assessors, and the Cohen's kappa statistic was then used to compare agreement. Light microscopy was the referent. Of all RDTs tested, 94.2 % (21/22) had sensitivity values greater than 90% among which 14 (63.6%) were 'Pf + PAN' RDTs. The specificity was generally lower than the sensitivity for all RDTs and poorer for "Pf Only" RDTs. The predictive values and likelihood ratios were better for non-HRP2 analytes for "Pf + PAN" RDTs. The Kappa value for most of the tests obtained was around 67% (95% CI 50-69%), corresponding to a moderate agreement. Overall, 94.2% (21/22) of RDTs tested had accuracy within the range recommended by the WHO, while one performed poorly, below acceptable levels. Seven "Pf + PAN" and 3 "Pf Only" RDTs were selected for further assessment based on performance characteristics. Harmonizing RDT test presentation and procedures would prevent mistakes of test performance and interpretation.

40 CFR 53.64 - Test procedure: Static fractionator test.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Test procedure: Static fractionator test. 53.64 Section 53.64 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Performance Characteristics of Class II Equivalent Methods for PM2.5 § 53.64 Test procedure: Static...

40 CFR 53.64 - Test procedure: Static fractionator test.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Test procedure: Static fractionator test. 53.64 Section 53.64 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Performance Characteristics of Class II Equivalent Methods for PM2.5 § 53.64 Test procedure: Static...

Physical dimensions, torsional performance, bending properties, and metallurgical characteristics of rotary endodontic instruments. VI. Canal Master drills.

PubMed

Luebke, N H; Brantley, W A; Sabri, Z I; Luebke, F L; Lausten, L L

1995-05-01

A laboratory study was performed on machine-driven Canal Master drills to determine their physical dimensions, torsional performance, bending properties, and metallurgical characteristics in fracture. Physical dimensions were determined for each of the available sizes (#50 to #100) of Canal Master drills from the manufacturer that distributes these instruments in the United States. Samples were also tested in clockwise torsion using a Maillefer memocouple. Bending properties of cantilever specimens were measured with a Tinius Olsen stiffness tester. Bending fatigue testing was performed on a unique laboratory apparatus. Scanning electron microscope examination confirmed visual observations that the stainless steel Canal Master drills exhibited ductile torsional fracture. This study is part of a continuing investigation to establish standards for all machine-driven rotary endodontic instruments.

Characteristics of an Optical Delay Line for Radar Testing

DTIC Science & Technology

2016-04-12

MANUFACTURER PERFORMANCE MEASUREMENT ....................................... 2 3 NRL PERFORMANCE MEASUREMENT ...Third-Order-Intercept (TOI) ................... 7 3.4 Phase Noise Measurement ...MANUFACTURER PERFORMANCE MEASUREMENT Figures 3 to 5 are the Miteq’s FODL performance measured by the manufacturer prior to shipping the system to NRL

Computer modeling of heat pipe performance

NASA Technical Reports Server (NTRS)

Peterson, G. P.

1983-01-01

A parametric study of the defining equations which govern the steady state operational characteristics of the Grumman monogroove dual passage heat pipe is presented. These defining equations are combined to develop a mathematical model which describes and predicts the operational and performance capabilities of a specific heat pipe given the necessary physical characteristics and working fluid. Included is a brief review of the current literature, a discussion of the governing equations, and a description of both the mathematical and computer model. Final results of preliminary test runs of the model are presented and compared with experimental tests on actual prototypes.

Almond Test Body. [for microwave anechoic chambers

NASA Technical Reports Server (NTRS)

Dominek, Allen K. (Inventor); Wood, Richard M. (Inventor); Gilreath, Melvin C. (Inventor)

1989-01-01

The invention is an almond shaped test body for use in measuring the performance characteristics of microwave anechoic chambers and for use as a support for components undergoing radar cross-section measurements. The novel aspect of this invention is its shape, which produces a large dynamic scattered field over large angular regions making the almond valuable for verifying the performance of microwave anechoic chambers. As a component mount, the almond exhibits a low return that does not perturb the measurement of the component and it simulates the backscatter characteristics of the component as if over an infinite ground plane.

Development of advanced fuel cell system

NASA Technical Reports Server (NTRS)

Grevstad, P. E.

1972-01-01

Weight, life and performance characteristics optimization of hydrogen-oxygen fuel cell power systems were considered. A promising gold alloy cathode catalyst was identified and tested in a cell for 5,000 hours. The compatibility characteristics of candidate polymer structural materials were measured after exposure to electrolyte and water vapor for 8,000 hours. Lightweight cell designs were prepared and fabrication techniques to produce them were developed. Testing demonstrated that predicted performance was achieved. Lightweight components for passive product water removal and evaporative cooling of cells were demonstrated. Systems studies identified fuel cell powerplant concepts for meeting the requirements of advanced spacecraft.

Analysis and test of a 16-foot radial rib reflector developmental model

NASA Technical Reports Server (NTRS)

Birchenough, Shawn A.

1989-01-01

Analytical and experimental modal tests were performed to determine the vibrational characteristics of a 16-foot diameter radial rib reflector model. Single rib analyses and experimental tests provided preliminary information relating to the reflector. A finite element model predicted mode shapes and frequencies of the reflector. The analyses correlated well with the experimental tests, verifying the modeling method used. The results indicate that five related, characteristic mode shapes form a group. The frequencies of the modes are determined by the relative phase of the radial ribs.

Experimental and Numerical Analysis of Performance Discontinuity of a Pump-Turbine under Pumping Mode

NASA Astrophysics Data System (ADS)

Zhang, X.; Burgstaller, R.; Lai, X.; Gehrer, A.; Kefalas, A.; Pang, Y.

2016-11-01

The performance discontinuity of a pump-turbine under pumping mode is harmful to stable operation of units in hydropower station. In this paper, the performance discontinuity phenomenon of the pump-turbine was studied by means of experiment and numerical simulation. In the experiment, characteristics of the pump-turbine with different diffuser vane openings were tested in order to investigate the effect of pumping casing to the performance discontinuity. While other effects such as flow separation and rotating stall are known to have an effect on the discontinuity, the present studied test cases show that prerotation is the dominating effect for the instability, positions of the positive slope of characteristics are almost the same in different diffuser vane opening conditions. The impeller has principal effect to the performance discontinuity. In the numerical simulation, CFD analysis of tested pump-turbine has been done with k-ω and SST turbulence model. It is found that the position of performance curve discontinuity corresponds to flow recirculation at impeller inlet. Flow recirculation at impeller inlet is the cause of the discontinuity of characteristics curve. It is also found that the operating condition of occurrence of flow recirculation at impeller inlet is misestimated with k-ω and SST turbulence model. Furthermore, the original SST model has been modified. We predict the occurrence position of flow recirculation at impeller inlet correctly with the modified SST turbulence model, and it also can improve the prediction accuracy of the pump- turbine performance at the same time.

40 CFR 53.63 - Test procedure: Wind tunnel inlet aspiration test.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Test procedure: Wind tunnel inlet... Testing Performance Characteristics of Class II Equivalent Methods for PM2.5 § 53.63 Test procedure: Wind... extracts an ambient aerosol at elevated wind speeds. This wind tunnel test uses a single-sized, liquid...

Final report on testing of TOPAZ II unit Ya-21u: Output power characteristics and system capabilities

NASA Astrophysics Data System (ADS)

Luchau, David W.; Sinkevich, Valery G.; Wernsman, Bernard; Mulder, Daniel M.

1996-03-01

A final report on the output power characteristics and capabilities of the TOPAZ II Space Nuclear Power Unit Ya-21u is presented. Results showed that after a total of almost 8,000 hours of system testing in the U.S. and Russia, several emergency cooldowns, and three inadvertent air introductions to the interelectrode gap (IEG) that the TOPAZ II demonstrates the potential for providing reliable power in a space environment. Output power optimizations and system characteristics following a shock and vibration test are shown. These tests were performed using electrical heaters that simulate nuclear fuel heating. This paper will focus primarily on the changes in output power characteristics over the lifetime of Ya-21u. All U.S. testing was conducted at the Thermionic System Evaluation Test (TSET) Facility of the New Mexico Engineering Research Institute (NMERI) as a part of the TOPAZ International Program (TIP). TIP is managed by the Air Force Phillips Laboratory (PL) for the Ballistic Missile Defense Organization (BMDO).

Measures of accuracy and performance of diagnostic tests.

PubMed

Drobatz, Kenneth J

2009-05-01

Diagnostic tests are integral to the practice of veterinary cardiology, any other specialty, and general veterinary medicine. Developing and understanding diagnostic tests is one of the cornerstones of clinical research. This manuscript describes the diagnostic test properties including sensitivity, specificity, predictive value, likelihood ratio, receiver operating characteristic curve. Review of practical book chapters and standard statistics manuscripts. Diagnostics such as sensitivity, specificity, predictive value, likelihood ratio, and receiver operating characteristic curve are described and illustrated. Basic understanding of how diagnostic tests are developed and interpreted is essential in reviewing clinical scientific papers and understanding evidence based medicine.

Anthropometric and performance measures to study talent detection in youth volleyball.

PubMed

Melchiorri, Giovanni; Viero, Valerio; Triossi, Tamara; Annino, Giuseppe; Padua, Elvira; Tancredi, Virginia

2017-12-01

The aim of this work was to study anthropometric and performance measurements in 60 young male volleyball players (YV) and 60 youth not active in the sport (YNA) to assess which of these would be more useful to study the characteristics of potential performers. Eight measures to assess anthropometric characteristics, six performance measures and two tests for joint mobility were used. Also relative age and level of maturation were assessed. The anthropometric variables, relative age and level of maturation measured did not show statistically significant differences between groups. The YV and YNA groups showed differences in the performance measures. YV group was characterized by a better performance of the ability to repeat short sprints, of the upper limbs, abdominal muscles and lower limbs, with a medium effect size (Shuttle Running Test: 0.6; Push-Up: 0.5; Sit-Up: 0.4; counter movement jump: 0.4). These performance variables were very sensitive and specific: the SRT measurement had the best positive likelihood ratio that indicates the utility of the test in identifying type of players (YV and YNA). In talent detection in youth volleyball, in the 11-13 age range, performance variables should be preferred to anthropometric ones.

Spread Spectrum Receiver Electromagnetic Interference (EMI) Test Guide

NASA Technical Reports Server (NTRS)

Wheeler, M. L.

1998-01-01

The objective of this test guide is to document appropriate unit level test methods and techniques for the performance of EMI testing of Direct Sequence (DS) spread spectrum receivers. Consideration of EMI test methods tailored for spread spectrum receivers utilizing frequency spreading, techniques other than direct sequence (such as frequency hopping, frequency chirping, and various hybrid methods) is beyond the scope of this test guide development program and is not addressed as part of this document EMI test requirements for NASA programs are primarily developed based on the requirements contained in MIL-STD-46 1 D (or earlier revisions of MIL-STD-46 1). The corresponding test method guidelines for the MIL-STD-461 D tests are provided in MIL-STD-462D. These test methods are well documented with the exception of the receiver antenna port susceptibility tests (intermodulation, cross modulation, and rejection of undesired signals) which must be tailored to the specific type of receiver that is being tested. Thus, test methods addressed in this guide consist only of antenna port tests designed to evaluate receiver susceptibility characteristics. MIL-STD-462D should be referred for guidance pertaining to test methods for EMI tests other than the antenna port tests. The scope of this test guide includes: (1) a discussion of generic DS receiver performance characteristics; (2) a summary of S-band TDRSS receiver operation; (3) a discussion of DS receiver EMI susceptibility mechanisms and characteristics; (4) a summary of military standard test guidelines; (5) recommended test approach and methods; and (6) general conclusions and recommendations for future studies in the area of spread spectrum receiver testing.

Liquid Oxygen/Liquid Methane Integrated Propulsion System Test Bed

NASA Technical Reports Server (NTRS)

Flynn, Howard; Lusby, Brian; Villemarette, Mark

2011-01-01

In support of NASA?s Propulsion and Cryogenic Advanced Development (PCAD) project, a liquid oxygen (LO2)/liquid methane (LCH4) Integrated Propulsion System Test Bed (IPSTB) was designed and advanced to the Critical Design Review (CDR) stage at the Johnson Space Center. The IPSTB?s primary objectives are to study LO2/LCH4 propulsion system steady state and transient performance, operational characteristics and to validate fluid and thermal models of a LO2/LCH4 propulsion system for use in future flight design work. Two phase thermal and dynamic fluid flow models of the IPSTB were built to predict the system performance characteristics under a variety of operating modes and to aid in the overall system design work. While at ambient temperature and simulated altitude conditions at the White Sands Test Facility, the IPSTB and its approximately 600 channels of system instrumentation would be operated to perform a variety of integrated main engine and reaction control engine hot fire tests. The pressure, temperature, and flow rate data collected during this testing would then be used to validate the analytical models of the IPSTB?s thermal and dynamic fluid flow performance. An overview of the IPSTB design and analytical model development will be presented.

Performance testing of supercapacitors: Important issues and uncertainties

NASA Astrophysics Data System (ADS)

Zhao, Jingyuan; Gao, Yinghan; Burke, Andrew F.

2017-09-01

Supercapacitors are a promising technology for high power energy storage, which have been used in some industrial and vehicles applications. Hence, it is important that information concerning the performance of supercapacitors be detailed and reliable so system designers can make rational decisions regarding the selection of the energy storage components. This paper is concerned with important issues and uncertainties regarding the performance testing of supercapacitors. The effect of different test procedures on the measured characteristics of both commercial and prototype supercapacitors including hybrid supercapacitors have been studied. It was found that the test procedure has a relatively minor effect on the capacitance of carbon/carbon devices and a more significant effect on the capacitance of hybrid supercapacitors. The device characteristic with the greatest uncertainty is the resistance and subsequently the claimed power capability of the device. The energy density should be measured by performing constant power discharges between appropriate voltage limits. This is particularly important in the case of hybrid supercapacitors for which the energy density is rate dependent and the simple relationship E = ½CV2 does not yield accurate estimates of the energy stored. In general, most of the important issues for testing carbon/carbon devices become more serious for hybrid supercapacitors.

Estimation procedures to measure and monitor failure rates of components during thermal-vacuum testing

NASA Technical Reports Server (NTRS)

Williams, R. E.; Kruger, R.

1980-01-01

Estimation procedures are described for measuring component failure rates, for comparing the failure rates of two different groups of components, and for formulating confidence intervals for testing hypotheses (based on failure rates) that the two groups perform similarly or differently. Appendix A contains an example of an analysis in which these methods are applied to investigate the characteristics of two groups of spacecraft components. The estimation procedures are adaptable to system level testing and to monitoring failure characteristics in orbit.

Characteristics of Extrinsic Fabry-Perot Interferometric (EFPI) Fiber-Optic Strain Gages

NASA Technical Reports Server (NTRS)

Hare, David A.; Moore, Thomas C., Sr.

2000-01-01

The focus of this paper is a comparison of the strain-measuring characteristics of one type of commercially available fiber-optic strain sensor with the performance of conventional resistance strain gages. Fabry-Perot type fiber-optic strain sensors were selected for this testing program. Comparative testing is emphasized and includes load testing at room temperature with apparent strain characterization cryogenically and at elevated temperatures. The absolute accuracy of either of these types of strain gages is not addressed.

Subsonic Wind Tunnel Tests of the FBTV Configuration in Proximity of the B-52

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

Priebe, R.W.

1966-12-01

Wind tunnel tests were conducted on a .075 scale Sandia FBTV store model in an 8-foot transonic wind tunnel during December `66. These tests were performed to obtain longitudinal and lateral stability characteristics.

49 CFR 178.609 - Test requirements for packagings for infectious substances.

Code of Federal Regulations, 2010 CFR

2010-10-01

... paragraph (c), which, for test purposes, categorizes packagings according to their material characteristics... performance may be rapidly affected by moisture; plastics that may embrittle at low temperature; and other... the appropriate test. Table I—Tests Required Material of Outer packaging Fiberboard Plastics Other...

Laboratory- and field-based testing as predictors of skating performance in competitive-level female ice hockey.

PubMed

Henriksson, Tommy; Vescovi, Jason D; Fjellman-Wiklund, Anncristine; Gilenstam, Kajsa

2016-01-01

The purpose of this study was to examine whether field-based and/or laboratory-based assessments are valid tools for predicting key performance characteristics of skating in competitive-level female hockey players. Cross-sectional study. Twenty-three female ice hockey players aged 15-25 years (body mass: 66.1±6.3 kg; height: 169.5±5.5 cm), with 10.6±3.2 years playing experience volunteered to participate in the study. The field-based assessments included 20 m sprint, squat jump, countermovement jump, 30-second repeated jump test, standing long jump, single-leg standing long jump, 20 m shuttle run test, isometric leg pull, one-repetition maximum bench press, and one-repetition maximum squats. The laboratory-based assessments included body composition (dual energy X-ray absorptiometry), maximal aerobic power, and isokinetic strength (Biodex). The on-ice tests included agility cornering s-turn, cone agility skate, transition agility skate, and modified repeat skate sprint. Data were analyzed using stepwise multivariate linear regression analysis. Linear regression analysis was used to establish the relationship between key performance characteristics of skating and the predictor variables. Regression models (adj R (2)) for the on-ice variables ranged from 0.244 to 0.663 for the field-based assessments and from 0.136 to 0.420 for the laboratory-based assessments. Single-leg tests were the strongest predictors for key performance characteristics of skating. Single leg standing long jump alone explained 57.1%, 38.1%, and 29.1% of the variance in skating time during transition agility skate, agility cornering s-turn, and modified repeat skate sprint, respectively. Isokinetic peak torque in the quadriceps at 90° explained 42.0% and 32.2% of the variance in skating time during agility cornering s-turn and modified repeat skate sprint, respectively. Field-based assessments, particularly single-leg tests, are an adequate substitute to more expensive and time-consuming laboratory assessments if the purpose is to gain knowledge about key performance characteristics of skating.

Laboratory- and field-based testing as predictors of skating performance in competitive-level female ice hockey

PubMed Central

Henriksson, Tommy; Vescovi, Jason D; Fjellman-Wiklund, Anncristine; Gilenstam, Kajsa

2016-01-01

Objectives The purpose of this study was to examine whether field-based and/or laboratory-based assessments are valid tools for predicting key performance characteristics of skating in competitive-level female hockey players. Design Cross-sectional study. Methods Twenty-three female ice hockey players aged 15–25 years (body mass: 66.1±6.3 kg; height: 169.5±5.5 cm), with 10.6±3.2 years playing experience volunteered to participate in the study. The field-based assessments included 20 m sprint, squat jump, countermovement jump, 30-second repeated jump test, standing long jump, single-leg standing long jump, 20 m shuttle run test, isometric leg pull, one-repetition maximum bench press, and one-repetition maximum squats. The laboratory-based assessments included body composition (dual energy X-ray absorptiometry), maximal aerobic power, and isokinetic strength (Biodex). The on-ice tests included agility cornering s-turn, cone agility skate, transition agility skate, and modified repeat skate sprint. Data were analyzed using stepwise multivariate linear regression analysis. Linear regression analysis was used to establish the relationship between key performance characteristics of skating and the predictor variables. Results Regression models (adj R2) for the on-ice variables ranged from 0.244 to 0.663 for the field-based assessments and from 0.136 to 0.420 for the laboratory-based assessments. Single-leg tests were the strongest predictors for key performance characteristics of skating. Single leg standing long jump alone explained 57.1%, 38.1%, and 29.1% of the variance in skating time during transition agility skate, agility cornering s-turn, and modified repeat skate sprint, respectively. Isokinetic peak torque in the quadriceps at 90° explained 42.0% and 32.2% of the variance in skating time during agility cornering s-turn and modified repeat skate sprint, respectively. Conclusion Field-based assessments, particularly single-leg tests, are an adequate substitute to more expensive and time-consuming laboratory assessments if the purpose is to gain knowledge about key performance characteristics of skating. PMID:27574474

Experimental investigation on Performance and Emission Characteristics of J20, P20, N20 Biodiesel blends and Sound Characteristics of P20 Biodiesel blend Used in Single Cylinder Diesel Engine

NASA Astrophysics Data System (ADS)

rajasekar, R.; karthik, N.; Xavier, Goldwin

2017-05-01

Present work provides the effect of biodiesel blends and Sound Characteristics of P20 Biodiesel blend compared with Performance and emission Characteristics of diesel. Methods and analysis biodiesel blends was prepared by the Transesterification Process. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Research is mainly focused on pongamia oil. It was observed that a 20% Pongamia oil blends and its properties were similar to diesel. The results showed that 20% Pongamia oil blends gave better performance, less in noise and emission compared with ester of Jatropha and neem oil blends. Hence Pongamia blends can be used in existing diesel engine without compromising the engine performance.

Measuring more than we know? An examination of the motivational and situational influences in science achievement

NASA Astrophysics Data System (ADS)

Haydel, Angela Michelle

The purpose of this dissertation was to advance theoretical understanding about fit between the personal resources of individuals and the characteristics of science achievement tasks. Testing continues to be pervasive in schools, yet we know little about how students perceive tests and what they think and feel while they are actually working on test items. This study focused on both the personal (cognitive and motivational) and situational factors that may contribute to individual differences in achievement-related outcomes. 387 eighth grade students first completed a survey including measures of science achievement goals, capability beliefs, efficacy related to multiple-choice items and performance assessments, validity beliefs about multiple-choice items and performance assessments, and other perceptions of these item formats. Students then completed science achievement tests including multiple-choice items and two performance assessments. A sample of students was asked to verbalize both thoughts and feelings as they worked through the test items. These think-alouds were transcribed and coded for evidence of cognitive, metacognitive and motivational engagement. Following each test, all students completed measures of effort, mood, energy level and strategy use during testing. Students reported that performance assessments were more challenging, authentic, interesting and valid than multiple-choice tests. They also believed that comparisons between students were easier using multiple-choice items. Overall, students tried harder, felt better, had higher levels of energy and used more strategies while working on performance assessments. Findings suggested that performance assessments might be more congruent with a mastery achievement goal orientation, while multiple-choice tests might be more congruent with a performance achievement goal orientation. A variable-centered analytic approach including regression analyses provided information about how students, on average, who differed in terms of their teachers' ratings of their science ability, achievement goals, capability beliefs and experiences with science achievement tasks perceived, engaged in, and performed on multiple-choice items and performance assessments. Person-centered analyses provided information about the perceptions, engagement and performance of subgroups of individuals who had different motivational characteristics. Generally, students' personal goals and capability beliefs related more strongly to test perceptions, but not performance, while teacher ratings of ability and test-specific beliefs related to performance.

Altitude-Test-Chamber Investigation of the Endurance and Performance Characteristics of the J65-W-7 Engine at a Mach Number of 2.0

NASA Technical Reports Server (NTRS)

Biermann, A.E.; Braithwaite, Willis M.

1955-01-01

An investigation of the endurance characteristics, at high Mach number, of the J65-W-7 engine was made in an altitude chamber at the Lewis laboratory. The investigation was made to determine whether this engine can be operated at flight conditions of Mach 2 at 35,000-feet altitude (inlet temperature, 250 F) as a limited-service-life engine Failure of the seventh-stage aluminum compressor blades occurred in both engines tested and was attributed to insufficient strength of the blade fastenings at the elevated temperatures. For the conditions of these tests, the results showed that it is reasonable to expect 10 to 15 minutes of satisfactory engine operation before failure. The high temperatures and pressures imposed upon the compressor housing caused no permanent deformation. In general, the performance of the engines tested was only slightly affected by the high ram conditions of this investigation. There was no discernible depreciation of performance with time prior to failure.

Program for refan JT8D engine design, fabrication and test, phase 2

NASA Technical Reports Server (NTRS)

Glass, J. A.; Zimmerman, E. S.; Scaramella, V. M.

1975-01-01

The objective of the JT8D refan program was to design, fabricate, and test certifiable modifications of the JT8D engine which would reduce noise generated by JT8D powered aircraft. This was to be accomplished without affecting reliability and maintainability, at minimum retrofit cost, and with no performance penalty. The mechanical design, engine performance and stability characteristics at sea-level and altitude, and the engine noise characteristics of the test engines are documented. Results confirmed the structural integrity of the JT8D-109. Engine operation was stable throughout the airplane flight envelope. Fuel consumption of the test engines was higher than that required to meet the goal of no airplane performance penalty, but the causes were identified and corrected during a normal pre-certification engine development program. Compared to the baseline JT8D-109 engine, the acoustically treated JT8D-109 engine showed noise reductions of 6 PNdB at takeoff and 11 PNdB at a typical approach power setting.

15 CFR 16.2 - Description and goal of program.

Code of Federal Regulations, 2014 CFR

2014-01-01

... standardized test methods by which selected product performance characteristics can be measured; (2) Developing... voluntarily to test and label their products according to the selected or developed methods; and (4...

15 CFR 16.2 - Description and goal of program.

Code of Federal Regulations, 2013 CFR

2013-01-01

... standardized test methods by which selected product performance characteristics can be measured; (2) Developing... voluntarily to test and label their products according to the selected or developed methods; and (4...

15 CFR 16.2 - Description and goal of program.

Code of Federal Regulations, 2012 CFR

2012-01-01

... standardized test methods by which selected product performance characteristics can be measured; (2) Developing... voluntarily to test and label their products according to the selected or developed methods; and (4...

Performance of the Multi-Spectral Solar Telescope Array. III - Optical characteristics of the Ritchey-Chretien and Cassegrain telescopes

NASA Astrophysics Data System (ADS)

Hoover, Richard B.; Baker, Phillip C.; Hadaway, James B.; Johnson, R. B.; Peterson, Cynthia; Gabardi, David R.; Walker, Arthur B., Jr.; Lindblom, J. F.; Deforest, Craig; O'Neal, R. H.

1991-12-01

The Multi-Spectral Solar Telescope Array (MSSTA), which is a sounding-rocket-borne observatory for investigating the sun in the soft X-ray/EUV and FUV regimes of the electromagnetic spectrum, utilizes single reflection multilayer coated Herschelian telescopes for wavelengths below 100 A, and five doubly reflecting multilayer coated Ritchey-Chretien and two Cassegrain telescopes for selected wavelengths in the EUV region between 100 and 1000 A. The paper discusses the interferometric alignment, testing, focusing, visible light testing, and optical performance characteristics of the Ritchey-Chretien and Cassegrain telescopes of MSSTA. A schematic diagram of the MSSTA Ritchey-Chretien telescope is presented together with diagrams of the system autocollimation testing.

Test and evaluation of constant-flow devices for use in SSN AFFF proportioning systems. Interim report, January-May 1986

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

Williams, F.W.; Back, G.G.; Burns, R.E.

1986-11-04

Constant flow devices, which deliver a constant flow of liquid over a range of upstream and downstream pressures, have been suggested as an alternative to orifice plates for proportioning AFFF in SSN 21 fire-suppression systems. Operational and performance characteristics of two lightweight, inexpensive, commercially available constant-flow devices have significant advantages over orifice plates. Both models tested, however, showed performance degradation when subjected to simulated service conditions. A constant flow device with improved resistance to wear and to AFFF exposure is desirable. Since the constant-flow control devices tested improves proportioning efficiency but do not have optimum characteristics, investigation of improved devicesmore » or methods is recommended.« less

Dynamic Test Method Based on Strong Electromagnetic Pulse for Electromagnetic Shielding Materials with Field-Induced Insulator-Conductor Phase Transition

NASA Astrophysics Data System (ADS)

Wang, Yun; Zhao, Min; Wang, Qingguo

2018-01-01

In order to measure the pulse shielding performance of materials with the characteristic of field-induced insulator-conductor phase transition when materials are used for electromagnetic shielding, a dynamic test method was proposed based on a coaxial fixture. Experiment system was built by square pulse source, coaxial cable, coaxial fixture, attenuator, and oscilloscope and insulating components. S11 parameter of the test system was obtained, which suggested that the working frequency ranges from 300 KHz to 7.36 GHz. Insulating performance is good enough to avoid discharge between conductors when material samples is exposed in the strong electromagnetic pulse field up to 831 kV/m. This method is suitable for materials with annular shape, certain thickness and the characteristic of field-induced insulator-conductor phase transition to get their shielding performances of strong electromagnetic pulse.

Thermal performance of multilayer insulations. [gas evacuation characteristics of three selected multilayer insulation composites

NASA Technical Reports Server (NTRS)

Keller, C. W.; Cunnington, G. R.; Glassford, A. P.

1974-01-01

Experimental and analytical studies were conducted in order to extend previous knowledge of the thermal performance and gas evacuation characteristics of three selected multilayer insulation (MLI) composites. Flat plate calorimeter heat flux measurements were obtained for 20- and 80- shield specimens using three representative layer densities over boundary temperatures ranging from 39 K (70 R) to 389 K (700 R). Laboratory gas evacuation tests were performed on representative specimens of each MLI composite after initially purging them with helium, nitrogen, or argon gases. In these tests, the specimens were maintained at temperatures between 128 K (230 R) and 300 K (540 R). Based on the results of the laboratory-scale tests, a composite MLI system consisting of 112 unperforated, double-aluminized Mylar reflective shields and 113 water preconditioned silk net spacer pairs was fabricated and installed on a 1.22-m-(4-ft-) diameter calorimeter tank.

Rotor performance characteristics from an aeroacoustic helicopter wind-tunnel test program

NASA Technical Reports Server (NTRS)

Hoad, D. R.; Elliott, J. W.; Orie, N. M.

1986-01-01

An investigation of helicopter rotor noise at model scale was conducted in the Langley 4 by 7 meter tunnel. The program described was the first of a planned three-phase project whose purpose was to examine the characteristic noise mechanism involved in main rotor/tail rotor interaction noise. This first phase was conducted with a main rotor only, in order to identify the characteristic noise generated by only the main rotor. The aerodynamic operating conditions of the rotor system were defined during the test. The acoustic data were properly referenced.

Test and evaluation report for the Grumman-Olson Kurbwatt

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

Barnett, J.H.; Carter, C.L.; Metcalfe, J.K.

1982-01-01

This report documents the results obtained from tests performed on the Kurbwatt, an electric vehicle (EV) designed and constructed by Grumman Olson (a divison of Grumman Allied Industries, Inc.), between August 1981 and April 1982 at the Tennessee Valley Authority (TVA) Electric Vehicle Test Facility (EVTF) in Chattanooga, Tennessee. Data on vehicle physical characteristics and performance acquired during tests conducted under test track, dynamometer, and on-road conditions are presented along with descriptions of the vehicle and its components and information on the reliability of the vehicle during the test period. This testing was performed by TVA and was sponsored bymore » the Electric Power Research Institute (EPRI).« less

Current Performance Characteristics of NASA Langley Research Center's Cockpit Motion Base and Standardized Test Procedure for Future Performance Characterization

NASA Technical Reports Server (NTRS)

Cowen, Brandon; Stringer, Mary T.; Hutchinson, Brian K.; Davidson, Paul C.; Gupton, Lawrence E.

2014-01-01

This report documents the updated performance characteristics of NASA Langley Research Center's (LaRC) Cockpit Motion Base (CMB) after recent revisions that were made to its inner-loop, feedback control law. The modifications to the control law will be briefly described. The performance of the Cockpit Motion Facility (CMF) will be presented. A short graphical comparison to the previous control law can be found in the appendix of this report. The revised controller will be shown to yield reduced parasitic accelerations with respect to the previous controller. Metrics based on the AGARD Advisory Report No. 144 are used to assess the overall system performance due to its recent control algorithm modification. This report also documents the standardized simulator test procedure which can be used in the future to evaluate potential updates to the control law.

Fuel Economy and Exhaust Emissions Characteristics of a Diesel Vehicle : Results of the Prototype Volkswagen 1.5 Liter Turbocharged Rabbit Tests

DOT National Transportation Integrated Search

1981-01-01

Tests were performed on a prototyple Vokswagen (VW) Turbocharged (TC) Rabbit diesel vehicle on a chassis dynamometer. The vheicle was tested for fuel economy and emissions on the urban Federal test Procedure (FTP), Highway Fuel Economy Test (HFET), C...

Testing of molded high temperature plastic actuator road seals for use in advanced aircraft hydraulic systems

NASA Technical Reports Server (NTRS)

Waterman, A. W.; Huxford, R. L.; Nelson, W. G.

1976-01-01

Molded high temperature plastic first and second stage rod seal elements were evaluated in seal assemblies to determine performance characteristics. These characteristics were compared with the performance of machined seal elements. The 6.35 cm second stage Chevron seal assembly was tested using molded Chevrons fabricated from five molding materials. Impulse screening tests conducted over a range of 311 K to 478 K revealed thermal setting deficiencies in the aromatic polyimide molding materials. Seal elements fabricated from aromatic copolyester materials structurally failed during impulse cycle calibration. Endurance testing of 3.85 million cycles at 450 K using MIL-H-83283 fluid showed poorer seal performance with the unfilled aromatic polyimide material than had been attained with seals machined from Vespel SP-21 material. The 6.35 cm first stage step-cut compression loaded seal ring fabricated from copolyester injection molding material failed structurally during impulse cycle calibration. Molding of complex shape rod seals was shown to be a potentially controllable technique, but additional molding material property testing is recommended.

Flight Test of GL-1 Glider Half Scale Prototype

NASA Astrophysics Data System (ADS)

Fikri Zulkarnain, Muhammad; Fazlur Rahman, Muhammad; Luthfi Imam Nurhakim, Muhammad; Arifianto, Ony; Mulyanto, Taufiq

2018-04-01

GL-1 is a single-seat mid-performance glider, designed to be Indonesian National Glider. The Glider have been developing since 2014. The development produced a half scale prototype called BL-1, which had accomplished static test in 2016, then followed by first flight test at April 20th 2017, and second flight test at May 21st 2017. The purpose of the flight test was to obtain familiarization of the aircraft, aerodynamics characteristics and flow visualization, with data from flight recorded in FDR. The flight test resulted in two flights with total length of 21 minutes. The data from FDR and flight test documents extracted to analyze the characteristics and behavior of the aircraft during flight test. The aerodynamics characteristic was close to analytical results. The control was good; however, the effectiveness of control surface may need to be further analyzed. The result of the flight test will be used as a reference for further improvements and may need further testing.

Characteristics of the group of radiologists that benefits the most using Breast Screen Reader Assessment Strategy (BREAST)

NASA Astrophysics Data System (ADS)

Ganesan, A.; Alakhras, M.; Brennan, P. C.; Lee, W.; Tapia, K.; Mello-Thoms, C.

2018-03-01

Purpose: To determine the impact of Breast Screen Reader Assessment Strategy (BREAST) over time in improving radiologists' breast cancer detection performance, and to identify the group of radiologists that benefit the most by using BREAST as a training tool. Materials and Methods: Thirty-six radiologists who completed three case-sets offered by BREAST were included in this study. The case-sets were arranged in radiologists' chronological order of completion and five performance measures (sensitivity, specificity, location sensitivity, receiver operating characteristics area under the curve (ROC AUC) and jackknife alternative free-response receiver operating characteristic (JAFROC) figure-of-merit (FOM)), available from BREAST, were compared between case-sets to determine the level of improvement achieved. The radiologists were then grouped based on their characteristics and the above performance measures between the case-sets were compared. Paired t-tests or Wilcoxon signed-rank tests with statistical significance set at p < 0.05 were used to compare the performance measures. Results: Significant improvement was demonstrated in radiologists' case-set performance in terms of location sensitivity and JAFROC FOM over the years, and radiologists' location sensitivity and JAFROC FOM showed significant improvement irrespective of their characteristics. In terms of ROC AUC, significant improvement was shown for radiologists who were reading screen mammograms for more than 7 years and spent more than 9 hours per week reading mammograms. Conclusion: Engaging with case-sets appears to enhance radiologists' performance suggesting the important value of initiatives such as BREAST. However, such performance enhancement was not shown for everyone, highlighting the need to tailor the BREAST platform to benefit all radiologists.

Crashworthiness testing of Amtrak's traditional coach seat : safety of high-speed ground transportation systems

DOT National Transportation Integrated Search

1996-10-01

Tests have been conducted on Amtrak's traditional passenger seat to evaluate its performance under static and dynamic loading conditions. Quasi-static tests have been conducted to establish the load-deflection characteristics of the seat. Dynamic tes...

Analysis of the design and performance characteristics of pumpable roof supports

PubMed Central

Timothy, Batchler

2017-01-01

Pumpable roof supports are currently being used to provide a safe working environment for longwall mining. Because different pumpable supports are visually similar and installed fundamentally in the same manner as other supports, there is a tendency to believe they all perform the same way. However, there are several design parameters that can affect their performance, including the cementitious material properties and the bag construction practices that influence the degree of confinement provided. A full understanding of the impact of these design parameters is necessary to optimize the support application and to provide a foundation for making further improvements in the support performance. This paper evaluates the impact of various support design parameters by examining full-scale performance tests conducted using the National Institute for Occupational Safety and Health (NIOSH) Mine Roof Simulator (MRS) as part of manufacturers’ developmental and quality control testing. These tests were analyzed to identify correlations between the support design parameters and the resulting performance. Based on more than 160 tests over 7 years, quantifiable patterns were examined to assess the correlation between the support dimensions, cementitious material type, wire pitch, and single-wall vs. dual-walled bag designs to the support capacity, stiffness, load shedding events, and yield characteristics. PMID:28775910

Electrical Characterization of the RCA CDP1822SD Random Access Memory, Volume 1, Appendix a

NASA Technical Reports Server (NTRS)

Klute, A.

1979-01-01

Electrical characteristization tests were performed on 35 RCA CDP1822SD, 256-by-4-bit, CMOS, random access memories. The tests included three functional tests, AC and DC parametric tests, a series of schmoo plots, rise/fall time screening, and a data retention test. All tests were performed on an automated IC test system with temperatures controlled by a thermal airstream unit. All the functional tests, the data retention test, and the AC and DC parametric tests were performed at ambient temperatures of 25 C, -20 C, -55 C, 85 C, and 125 C. The schmoo plots were performed at ambient temperatures of 25 C, -55 C, and 125 C. The data retention test was performed at 25 C. Five devices failed one or more functional tests and four of these devices failed to meet the expected limits of a number of AC parametric tests. Some of the schmoo plots indicated a small degree of interaction between parameters.

40 CFR 53.42 - Generation of test atmospheres for wind tunnel tests.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Generation of test atmospheres for wind... Testing Performance Characteristics of Methods for PM10 § 53.42 Generation of test atmospheres for wind... particle delivery system shall consist of a blower system and a wind tunnel having a test section of...

40 CFR 53.42 - Generation of test atmospheres for wind tunnel tests.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Generation of test atmospheres for wind... Testing Performance Characteristics of Methods for PM10 § 53.42 Generation of test atmospheres for wind... particle delivery system shall consist of a blower system and a wind tunnel having a test section of...

Storm wave buoy equipped with micromechanical inertial unit: Results of development and testing

NASA Astrophysics Data System (ADS)

Gryazin, D. G.; Staroselcev, L. P.; Belova, O. O.; Gleb, K. A.

2017-07-01

The article describes the results of developing a wave buoy to measure the statistical characteristics of waves and the characteristics of directional spectra of three-dimensional waves. The device is designed for long-term measurements lasting up to a season, which can help solve problems in forecasting waves and preventing emergencies from wave impact on offshore platforms, hydraulic structures, and other marine facilities. The measuring unit involves triads of micromechanical gyroscopes, accelerometers, and a three-component magnetometer. A description of the device, results of laboratory research of its characteristics, and bench and full-scale tests are offered. It is noted that to assess the performance characteristics, comparative tests of the Storm wave buoy were conducted with a standard string wave probe installed on an offshore platform. It is shown that the characteristics and capabilities of the wave buoy make it possible to oust foreign devices from the domestic market.

Pavement performance testing : research implementation plan.

DOT National Transportation Integrated Search

2005-01-01

STATEMENT OF NEED: Validate effect of materials variables in the Superpave mix design system as : affects rutting and fatigue performance. : RESEARCH OBJECTIVES: 1. Determine the effect of aggregate characteristics and gradation and polymer modifier ...

Hydraulic Performance of Conflict Manholes

DOT National Transportation Integrated Search

1999-11-01

This report details a performance analysis of conflict junction boxes, employed when stormwater lines intersect utility conduits. A variety of configurations currently used by FDOT were tested and rated for turbulent loss characteristics. Special con...

Research on roadway performance and distress at low temperature.

DOT National Transportation Integrated Search

2012-06-01

This research project investigated the performance and damage characteristics of Nebraska roadways at low-temperature : conditions. To meet the research objective, laboratory tests were incorporated with mechanistic numerical modeling. The : three mo...

Is Higher Better? Determinants and Comparisons of Performance on the Major Field Test in Business

ERIC Educational Resources Information Center

Bielinska-Kwapisz, Agnieszka; Brown, F. William; Semenik, Richard

2012-01-01

Student performance on the Major Field Achievement Test in Business is an important benchmark for college of business programs. The authors' results indicate that such benchmarking can only be meaningful if certain student characteristics are taken into account. The differences in achievement between cohorts are explored in detail by separating…

Job characteristics, flow, and performance: the moderating role of conscientiousness.

PubMed

Demerouti, Evangelia

2006-07-01

The present article aims to show the importance of positive work-related experiences within occupational health psychology by examining the relationship between flow at work (i.e., absorption, work enjoyment, and intrinsic work motivation) and job performance. On the basis of the literature, it was hypothesized that (a) motivating job characteristics are positively related to flow at work and (b) conscientiousness moderates the relationship between flow and other ratings of (in-role and out-of-role) performance. The hypotheses were tested on a sample of 113 employees from several occupations. Results of moderated structural equation modeling analyses generally supported the hypotheses. Motivating job characteristics were predictive of flow, and flow predicted in-role and extra-role performance, for only conscientious employees.

Cryogenic Fracture Toughness Evaluation of an Investment Cast Al-Be Alloy for Structural Applications

NASA Technical Reports Server (NTRS)

Gamwell, W. R.; McGill, P. B.

2006-01-01

Aluminum-Beryllium metal matrix composite materials are useful due to their desirable performance characteristics for aerospace applications. Desirable characteristics of this material includes light-weight, dimensional stability, stiffness, good vibration damping characteristics, low coefficient of thermal expansion, and workability, This material is 3.5 times stiffer and 22% lighter than conventional aluminum alloys. electro-optical systems, advanced sensor and guidance components for flight and satellite systems, components for light-weight high-performance aircraft engines, and structural components for helicopters. Aluminum-beryllium materials are now available in the form of near net shape investment castings. In this materials properties characterization study, the cryogenic tensile and fracture properties of an investment casting alloy, Beralcast 363, were determined. Tensile testing was performed at 21 C (70 F), -73.3 C (-100 F), -195.5 C (-320 F) and -252.8 C (-423 F), and fracture (K(sub lc) and da/dN) testing was performed at -73.3 C (-100 F), -195.5 C (-320 F) and -252.8 C (-423 F). Their use is attractive for weight critical structural applications such as advanced

An active interference projector for the electro-optical test facility

NASA Astrophysics Data System (ADS)

Crowe, D. G.; Nowak, T. M.

1980-09-01

A projection system is described which can simulate emissions from flares, muzzle-flashes, shellbursts, and other emissive agents which may degrade the performance of electro-optical systems in the 0.5-15 micron spectral range. The simulation capability obtained will allow the apparent radiance and temporal characteristics of muzzleflashes and shellbursts to be mimicked at simulated ranges as close as 23 m within the Electro-Optical Test Facility. This demonstrates that tests of electro-optical system performance in the presence of interferers can be performed under laboratory conditions with higher repeatability and lower cost than field tests.

Test Program for Evaluation of Variable Frequency Power Conditioners

DOT National Transportation Integrated Search

1973-08-01

A test program is outlined for variable frequency power conditioners for 3-phase induction motors in vehicle propulsion applications. The Power Conditioner Unit (PCU) performance characteristics are discussed in some detail. Measurement methods, reco...

ARC-1964-AC-32744

NASA Image and Video Library

1964-06-19

XV-5A airplane installed in 40x80ft Subsonic Wind Tunnel at NASA Ames Research Center with Tom Mills. The propulsive lift system was tested to determine power-on performance characteristics in preparation for flight tests.

ARC-1901-AC-32746

NASA Image and Video Library

1964-06-19

XV-5A airplane installed in 40x80ft Subsonic Wind Tunnel at NASA Ames Research Center with Tom Mills. The propulsive lift system was tested to determine power-on performance characteristics in preparation for flight tests.

A procedure obtaining stiffnesses and masses of a structure from vibration modes and substructure static test data

NASA Technical Reports Server (NTRS)

Edighoffer, H. H.

1979-01-01

A component mode desynthesis procedure is developed for determining the unknown vibration characteristics of a structural component (i.e., a launch vehicle) given the vibration characteristics of a structural system composed of that component combined with a known one (i.e., a payload). At least one component static test has to be performed. These data are used in conjunction with the system measured frequencies and mode shapes to obtain the vibration characteristics of each component. The flight dynamics of an empty launch vehicle can be determined from measurements made on a vehicle/payload combination in conjunction with a static test on the payload.

Influence of Antioxidant Addition in Jatropha Biodiesel on the Performance, Combustion and Emission Characteristics of a DI Diesel Engine

NASA Astrophysics Data System (ADS)

Arockiasamy, Prabu; Ramachandran Bhagavathiammal, Anand

2018-04-01

An experimental investigation is conducted on a single-cylinder DI diesel engine, to evaluate the performance, combustion and emission characteristics of Jatropha biodiesel with the addition of antioxidants namely, Succinimide (C4H5NO2), N,N-Dimethyl p-phenylenediamine dihydrochloride (C8H14Cl2N2) and N-Phenyl- p-phenylenediamine (C6H5NHC6H4NH2) at 500, 1000 and 2000 ppm. The performance, combustion and emission characteristic tests are conducted at a constant speed of 1500 rpm, injection pressure of 215 bar, injection timing of 26° before top dead centre for the nine test fuels and the experimental results are compared with neat diesel and neat biodiesel as base fuels. The experimental results show that the addition of antioxidant in biodiesel suppresses the NO emission by quenching the OH radicals that are produced by the reaction of hydrocarbon radicals with molecular nitrogen. The maximum percentage reduction of NO emission by 5, 6 and 7% are observed for N-Phenyl- p-phenylenediamine, N,N-Dimethyl p-phenylenediamine dihydrochloride and Succinimide blended test fuels at 2000 ppm antioxidant addition with biodiesel.

Development of a non-tissue adherent neurosurgical patty and an ex vivo testing system to evaluate adherent characteristics.

PubMed

Kinoshita, Manabu; Taniguchi, Mai; Takagaki, Masatoshi; Seike, Nobuhisa; Hashimoto, Naoya; Yoshimine, Toshiki

2015-05-01

Neurosurgical patties are the most frequently used instruments during neurosurgical procedures, and their high performance is required to ensure safe operations. They must offer cushioning, water-absorbing, water-retaining, and non-tissue adherent characteristics. Here, the authors describe a revised neurosurgical patty that is superior in all respects to the conventional patty available in Japan. Patty characteristics were critically and scientifically evaluated using various in vitro assays. Moreover, a novel ex vivo evaluation system focusing on the adherent characteristics of the neurosurgical patty was developed. The proposed assay could provide benchmark data for comparing different neurosurgical patties, offering neurosurgeons objective data on the performance of patties. The newly developed patty was also evaluated in real neurosurgical settings and showed superb performance during various neurosurgical procedures.

Cooling characteristics of air cooled radial turbine blades

NASA Astrophysics Data System (ADS)

Sato, T.; Takeishi, K.; Matsuura, M.; Miyauchi, J.

The cooling design and the cooling characteristics of air cooled radial turbine wheels, which are designed for use with the gas generator turbine for the 400 horse power truck gas turbine engine, are presented. A high temperature and high speed test was performed under aerodynamically similar conditions to that of the prototype engine in order to confirm the metal temperature of the newly developed integrated casting wheels constructed of the superalloys INCO 713C. The test results compared with the analytical value, which was established on the basis of the results of the heat transfer test and the water flow test, are discussed.

Study of LTPP laboratory resilient modulus test data and response characteristics.

DOT National Transportation Integrated Search

2002-10-01

The resilient modulus of every unbound structural layer of the Long Term Pavement Performance (LTPP) Specific Pavement and : General Pavement Studies Test Sections is being measured in the laboratory using LTPP test protocol P46. A total of 2,014 : r...

40 CFR 53.58 - Operational field precision and blank test.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent... samplers are also subject to a test for possible deposition of particulate matter on inactive filters...

40 CFR 53.58 - Operational field precision and blank test.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROGRAMS (CONTINUED) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent... samplers are also subject to a test for possible deposition of particulate matter on inactive filters...

40 CFR 53.58 - Operational field precision and blank test.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent... samplers are also subject to a test for possible deposition of particulate matter on inactive filters...

40 CFR 53.58 - Operational field precision and blank test.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent... samplers are also subject to a test for possible deposition of particulate matter on inactive filters...

Status of the NOAO evaluation of the Hughes 20x64 Si:As impurity band conduction array. [for ground and space-based astronomy

NASA Technical Reports Server (NTRS)

Fowler, A. M.; Joyce, R. R.

1990-01-01

The Hughes 20 x 64 Si:As impurity band conduction arrays designed for ground-based and spaceborne astronomy observations is described together with experiments performed at NOAO to test these arrays. Special attention is given to the design and the characteristics of the test system and to the test methods. The initial tests on two columns of one array indicate that the array is easy to operate and performed satisfactorily.

Performance Characterization of the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) CCD Cameras

NASA Technical Reports Server (NTRS)

Joiner, Reyann; Kobayashi, Ken; Winebarger, Amy; Champey, Patrick

2014-01-01

The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a sounding rocket instrument which is currently being developed by NASA's Marshall Space Flight Center (MSFC) and the National Astronomical Observatory of Japan (NAOJ). The goal of this instrument is to observe and detect the Hanle effect in the scattered Lyman-Alpha UV (121.6nm) light emitted by the Sun's Chromosphere to make measurements of the magnetic field in this region. In order to make accurate measurements of this effect, the performance characteristics of the three on-board charge-coupled devices (CCDs) must meet certain requirements. These characteristics include: quantum efficiency, gain, dark current, noise, and linearity. Each of these must meet predetermined requirements in order to achieve satisfactory performance for the mission. The cameras must be able to operate with a gain of no greater than 2 e(-)/DN, a noise level less than 25e(-), a dark current level which is less than 10e(-)/pixel/s, and a residual nonlinearity of less than 1%. Determining these characteristics involves performing a series of tests with each of the cameras in a high vacuum environment. Here we present the methods and results of each of these performance tests for the CLASP flight cameras.

Expanded HIV Testing Strategy Leveraging the Electronic Medical Record Uncovers Undiagnosed Infection Among Hospitalized Patients.

PubMed

Felsen, Uriel R; Cunningham, Chinazo O; Heo, Moonseong; Futterman, Donna C; Weiss, Jeffrey M; Zingman, Barry S

2017-05-01

Routine HIV testing of hospitalized patients is recommended, but few strategies to expand testing in the hospital setting have been described. We assessed the impact of an electronic medical record (EMR) prompt on HIV testing for hospitalized patients. We performed a pre-post study at 3 hospitals in the Bronx, NY. We compared the proportion of admissions of patients 21-64 years old with an HIV test performed, characteristics of patients tested, and rate of new HIV diagnoses made by screening while an EMR prompt recommending HIV testing was inactive vs. active. The prompt appeared for patients with no previous HIV test or a high-risk diagnosis after their last HIV test. Among 36,610 admissions while the prompt was inactive, 9.5% had an HIV test performed. Among 18,943 admissions while the prompt was active, 21.8% had an HIV test performed. Admission while the prompt was active was associated with increased HIV testing among total admissions [adjusted odds ratio (aOR) 2.78, 95% confidence interval (CI): 2.62 to 2.96], those without a previous HIV test (aOR 4.03, 95% CI: 3.70 to 4.40), and those with a previous negative test (aOR 1.52, 95% CI: 1.37 to 1.68) (P < 0.0001 for all). Although the prompt was active, testing increased across all patient characteristics. New HIV diagnoses made by screening increased from 8.2/100,000 admissions to 37.0/100,000 admissions while the prompt was inactive and active, respectively (OR 4.51 95% CI: 1.17 to 17.45, P = 0.03). An EMR prompt for hospitalized patients was associated with a large increase in HIV testing, a diversification of patients tested, and an increase in diagnoses made by screening.

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

NASA Technical Reports Server (NTRS)

Fasching, W. A.

1980-01-01

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

Proposed acceptance, qualification, and characterization tests for thin-film PV modules

NASA Technical Reports Server (NTRS)

Waddington, D.; Mrig, L.; Deblasio, R.; Ross, R.

1988-01-01

Details of a proposed test program for PV thin-film modules which the Department of Energy has directed the Solar Energy Research Institute (SERI) to prepare are presented. Results of one of the characterization tests that SERI has performed are also presented. The objective is to establish a common approach to testing modules that will be acceptable to both users and manufacturers. The tests include acceptance, qualification, and characterization tests. Acceptance tests verify that randomly selected modules have similar characteristics. Qualification tests are based on accelerated test methods designed to simulate adverse conditions. Characterization tests provide data on performance in a predefined environment.

Kinanthropometric and performance characteristics of elite and non-elite female softball players.

PubMed

Singh, S; Singh, M; Rathi, B

2013-12-01

The purpose of the present study was to compare the kinanthropometric and performance characteristics of elite and non-elite female softball players. A total forty elite and non-elite level female softball players were selected from the different colleges affiliated to the Guru Nanak Dev University, Amritsar, for the present study. The height of subjects was measured by using the standard anthropometric rod. Weight was measured with portable weighing machine. Widths and diameters of body parts were measured by using digital caliper. Girths and lengths were taken with steel tape. Skinfold thickness measurements were taken using the Slimguide skinfold caliper. All subjects were also assessed for performance tests i.e. vertical jump, 50m sprint, medicine ball throw, 10×4m shuttle run and reaction time. Independent samples t-test reveals that elite female softball players were significantly taller (P<0.05) than the non- elite players. The elite female softball players also had significantly greater biacromial (P<0.05), bi- illiocristal (P<0.05) and bicondylar femur (P<0.05) diameters and forearm circumference (P<0.05) as compared to non-elite female softball players. The non-elite female softball players were found to have significantly greater thigh circumference (P<0.05), triceps (P<0.05) and subscapular (P<0.05) skinfold thicknesses than the elite female softball players. The non-elite players were also found to have significantly higher percentage body fat (P<0.05) than the elite players. In performance tests, the elite players were found to have significantly better reaction time (P<0.05), speed (P<0.05) and agility (P<0.05) as compared to non-elite female softball players. The elite female softball players had significantly greater kinanthropometric characteristics, body composition and performance characteristics than the non-elite female softball players.

Aerodynamic Characteristics of a 45 Degree Swept-wing Fighter-Airplane Model and Aerodynamic Loads on Adjacent Stores and Missiles at Mach Numbers of 1.57, 1.87, 2.16, and 2.53

NASA Technical Reports Server (NTRS)

Oehman, Waldo I; Turner, Kenneth L

1958-01-01

An investigation was performed in the Langley Unitary Plan wind tunnel to determine the aerodynamic characteristics of a model of a 450 swept-wing fighter airplane, and to determine the loads on attached stores and detached missiles in the presence of the model. Also included was a determination of aileron-spoiler effectiveness, aileron hinge moments, and the effects of wing modifications on model aerodynamic characteristics. Tests were performed at Mach numbers of 1.57, 1.87, 2.16, and 2.53. The Reynolds numbers for the tests, based on the mean aerodynamic chord of the wing, varied from about 0.9 x 10(exp 6) to 5 x 10(exp 6). The results are presented with minimum analysis.

MSG test report-steady-state heat transfer. [LMFBR

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

Harty, R.B.

This report documents the results of the Steady-State Heat Transfer Tests conducted on the AI Modular Steam Generator (MSG), at the Sodium Component Test Installation (SCTI) of the Liquid Metal Engineering Center. Heat transfer and pressure drop performance data are given along with current predictions of performance. Departure from nucleate boiling characteristics is given. A dispersed flow film boiling model, employing thermal nonequilibrium, was used to analyze data in the film boiling region.

Evaluation plan for space station network interface units

NASA Technical Reports Server (NTRS)

Weaver, Alfred C.

1990-01-01

Outlined here is a procedure for evaluating network interface units (NIUs) produced for the Space Station program. The procedures should be equally applicable to the data management system (DMS) testbed NIUs produced by Honeywell and IBM. The evaluation procedures are divided into four areas. Performance measurement tools are hardware and software that must be developed in order to evaluate NIU performance. Performance tests are a series of tests, each of which documents some specific characteristic of NIU and/or network performance. In general, these performance tests quantify the speed, capacity, latency, and reliability of message transmission under a wide variety of conditions. Functionality tests are a series of tests and code inspections that demonstrate the functionality of the particular subset of ISO protocols which have been implemented in a given NIU. Conformance tests are a series of tests which would expose whether or not selected features within the ISO protocols are present and interoperable.

Performance tests of a power-electronics converter for multi-megawatt wind turbines using a grid emulator

NASA Astrophysics Data System (ADS)

Rizqy Averous, Nurhan; Berthold, Anica; Schneider, Alexander; Schwimmbeck, Franz; Monti, Antonello; De Doncker, Rik W.

2016-09-01

A vast increase of wind turbines (WT) contribution in the modern electrical grids have led to the development of grid connection requirements. In contrast to the conventional test method, testing power-electronics converters for WT using a grid emulator at Center for Wind Power Drives (CWD) RWTH Aachen University offers more flexibility for conducting test scenarios. Further analysis on the performance of the device under test (DUT) is however required when testing with grid emulator since the characteristic of the grid emulator might influence the performance of the DUT. This paper focuses on the performance analysis of the DUT when tested using grid emulator. Beside the issue regarding the current harmonics, the performance during Fault Ride-Through (FRT) is discussed in detail. A power hardware in the loop setup is an attractive solution to conduct a comprehensive study on the interaction between the power-electronics converters and the electrical grids.

Fracture characteristics of structural aerospace alloys containing deep surface flaws. [aluminum-titanium alloys

NASA Technical Reports Server (NTRS)

Masters, J. N.; Bixler, W. D.; Finger, R. W.

1973-01-01

Conditions controlling the growth and fracture of deep surface flaws in aerospace alloys were investigated. Static fracture tests were performed on 7075-T651 and 2219-T87 aluminum, and 6Ai-4V STA titanium . Cyclic flaw growth tests were performed on the two latter alloys, and sustain load tests were performed on the titanium alloy. Both the cyclic and the sustain load tests were performed with and without a prior proof overload cycle to investigate possible growth retardation effects. Variables included in all test series were thickness, flaw depth-to-thickness ratio, and flaw shape. Results were analyzed and compared with previously developed data to determine the limits of applicability of available modified linear elastic fracture solutions.

King 2 2519 ATM residual gyros: Reestablishing 5 year life requirements

NASA Technical Reports Server (NTRS)

Kayal, B.; Carbocci, L. J.

1978-01-01

The technical expertise required to assess the condition of the residual ATM 2519 Singer gyros is discussed. Past build history records, past performance characteristics, and recommendations for particular tests (which were performed by NASA personnel) are summarized. Test results are analyzed. A study of motor performance data and recommendations concerning gyro spin bearing life was performed. A method of reestablishing potential reliability of the bearing for the 5-year life requirement of the power module is also included.

Effects of Optical Artifacts in a Laser-Based Spacecraft Navigation Sensor

NASA Technical Reports Server (NTRS)

LeCroy, Jerry E.; Howard, Richard T.; Hallmark, Dean S.

2007-01-01

Testing of the Advanced Video Guidance Sensor (AVGS) used for proximity operations navigation on the Orbital Express ASTRO spacecraft exposed several unanticipated imaging system artifacts and aberrations that required correction to meet critical navigation performance requirements. Mitigation actions are described for a number of system error sources, including lens aberration, optical train misalignment, laser speckle, target image defects, and detector nonlinearity/noise characteristics. Sensor test requirements and protocols are described, along with a summary of test results from sensor confidence tests and system performance testing.

Effects of Optical Artifacts in a Laser-Based Spacecraft Navigation Sensor

NASA Technical Reports Server (NTRS)

LeCroy, Jerry E.; Hallmark, Dean S.; Howard, Richard T.

2007-01-01

Testing Of the Advanced Video Guidance Sensor (AVGS) used for proximity operations navigation on the Orbital Express ASTRO spacecraft exposed several unanticipated imaging system artifacts and aberrations that required correction, to meet critical navigation performance requirements. Mitigation actions are described for a number of system error sources, including lens aberration, optical train misalignment, laser speckle, target image defects, and detector nonlinearity/noise characteristics. Sensor test requirements and protocols are described, along with a summary ,of test results from sensor confidence tests and system performance testing.

Realization of the D-15 Color Blindness Test System on PC

NASA Astrophysics Data System (ADS)

Ogawa, Tsuyoshi; Meguro, Mitsuhiko; Taguchi, Akira

Farnsworth D15 test is one of famous color blindness tests. The type of the color blindness and as well its severity can be known by this test. When we perform Farnsworth D15 test using a PC, we investigate the conditions (i.e., color temperature, gamma characteristic and luminance) for a monitor, experimentally.

Tests of commercial colour CMOS cameras for astronomical applications

NASA Astrophysics Data System (ADS)

Pokhvala, S. M.; Reshetnyk, V. M.; Zhilyaev, B. E.

2013-12-01

We present some results of testing commercial colour CMOS cameras for astronomical applications. Colour CMOS sensors allow to perform photometry in three filters simultaneously that gives a great advantage compared with monochrome CCD detectors. The Bayer BGR colour system realized in colour CMOS sensors is close to the astronomical Johnson BVR system. The basic camera characteristics: read noise (e^{-}/pix), thermal noise (e^{-}/pix/sec) and electronic gain (e^{-}/ADU) for the commercial digital camera Canon 5D MarkIII are presented. We give the same characteristics for the scientific high performance cooled CCD camera system ALTA E47. Comparing results for tests of Canon 5D MarkIII and CCD ALTA E47 show that present-day commercial colour CMOS cameras can seriously compete with the scientific CCD cameras in deep astronomical imaging.

Pollution reduction technology program small jet aircraft engines, phase 3

NASA Technical Reports Server (NTRS)

Bruce, T. W.; Davis, F. G.; Kuhn, T. E.; Mongia, H. C.

1981-01-01

A series of Model TFE731-2 engine tests were conducted with the Concept 2 variable geometry airblast fuel injector combustion system installed. The engine was tested to: (1) establish the emission levels over the selected points which comprise the Environmental Protection Agency Landing-Takeoff Cycle; (2) determine engine performance with the combustion system; and (3) evaulate the engine acceleration/deceleration characteristics. The hydrocarbon (HC), carbon monoxide (CO), and smoke goals were met. Oxides of nitrogen (NOx) were above the goal for the same configuration that met the other pollutant goals. The engine and combustor performance, as well as acceleration/deceleration characteristics, were acceptable. The Concept 3 staged combustor system was refined from earlier phase development and subjected to further rig refinement testing. The concept met all of the emissions goals.

Who Goes to Graduate School? Tracking 2003 ACT®-Tested High School Graduates for More than a Decade. ACT Research Report Series, 2015 (2)

ERIC Educational Resources Information Center

Mattern, Krista; Radunzel, Justine

2015-01-01

Many students who earn a bachelor's degree also aspire to earn a graduate degree. In this study, we examined student and institutional characteristics that are related to graduate school enrollment. Student characteristics included demographic characteristics; high school performance measures, coursework taken, and extracurricular activities;…

Wind tunnel tests of four flexible wing ultralight gliders

NASA Technical Reports Server (NTRS)

Ormiston, R. A.

1979-01-01

The aerodynamic lift, drag, and pitching moment characteristics of four full scale, flexible wing, ultralight gliders were measured in the settling chamber of a low speed wind tunnel. The gliders were tested over a wide range of angle of attack and at two different velocities. Particular attention was devoted to the lift and pitching moment behavior at low and negative angles of attack because of the potential loss of longitudinal stability of flexible wing gliders in this regime. The test results were used to estimate the performance and longitudinal control characteristics of the gliders.

Louisiana experimental base project : interim report No. 1.

DOT National Transportation Integrated Search

1979-11-01

The Louisiana Experimental Base Project is a research study evaluating the design/performance characteristics of three types of base courses as incorporated into comparable flexible pavement systems on a full-scale test road. Fourteen different test ...

OAO-3 end of mission power subsystem evaluation

NASA Technical Reports Server (NTRS)

Tasevoli, M.

1982-01-01

End of mission tests were performed on the OAO-3 power subsystem in three component areas: solar array, nickel-cadmium batteries and the On-Board Processor (OBP) power boost operation. Solar array evaluation consisted of analyzing array performance characteristics and comparing them to earlier flight data. Measured solar array degradation of 14.1 to 17.7% after 8 1/3 years is in good agreement with theortical radiation damage losses. Battery discharge characteristics were compared to results of laboratory life cycle tests performed on similar cells. Comparison of cell voltage profils reveals close correlation and confirms the validity of real time life cycle simulation. The successful operation of the system in the OBP/power boost regulation mode demonstrates the excellent life, reliability and greater system utilization of power subsystems using maximum power trackers.

Effect of Free Stream Turbulence on the Performance of a Marine Hydrokinetic Turbine

NASA Astrophysics Data System (ADS)

Vinod, Ashwin; Banerjee, Arindam

2015-11-01

The effects of controlled and elevated levels of free stream turbulence on the performance characteristics of a three bladed, constant chord, untwisted marine hydrokinetic turbine is tested experimentally. Controlled homogeneous free stream turbulence levels ranging from 3% to ~20% are achieved by employing an active grid turbulence generator that is placed at the entrance of the water channel test section and is equipped with motor controlled winglet shafts. In addition to free stream turbulence, various (turbine) operating conditions such as the free stream velocity and rotational speed are varied. A comparison of performance characteristics that includes the mean and standard deviations of the power coefficient (CP) , and thrust coefficient (CT) will be presented and compared to the case of a laminar free stream with FST levels <1%.

Performance and combustion characteristics of direct-injection stratified-charge rotary engines

NASA Technical Reports Server (NTRS)

Nguyen, Hung Lee

1987-01-01

Computer simulations of the direct-injection stratified-charge (DISC) Wankel engine have been used to calculate heat release rates and performance and efficiency characteristics of the 1007R engine. Engine pressure data have been used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine performance data are compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the Wankel engine with faster combustion, reduced leakage, higher compression ratio, and turbocharging is presented.

Analysis of the performance, emission and combustion characteristics of a turbocharged diesel engine fuelled with Jatropha curcas biodiesel-diesel blends using kernel-based extreme learning machine.

PubMed

Silitonga, Arridina Susan; Hassan, Masjuki Haji; Ong, Hwai Chyuan; Kusumo, Fitranto

2017-11-01

The purpose of this study is to investigate the performance, emission and combustion characteristics of a four-cylinder common-rail turbocharged diesel engine fuelled with Jatropha curcas biodiesel-diesel blends. A kernel-based extreme learning machine (KELM) model is developed in this study using MATLAB software in order to predict the performance, combustion and emission characteristics of the engine. To acquire the data for training and testing the KELM model, the engine speed was selected as the input parameter, whereas the performance, exhaust emissions and combustion characteristics were chosen as the output parameters of the KELM model. The performance, emissions and combustion characteristics predicted by the KELM model were validated by comparing the predicted data with the experimental data. The results show that the coefficient of determination of the parameters is within a range of 0.9805-0.9991 for both the KELM model and the experimental data. The mean absolute percentage error is within a range of 0.1259-2.3838. This study shows that KELM modelling is a useful technique in biodiesel production since it facilitates scientists and researchers to predict the performance, exhaust emissions and combustion characteristics of internal combustion engines with high accuracy.

Special Workshop: Kolsky/Split Hopkinson Pressure Bar Testing of Ceramics

DTIC Science & Technology

2006-09-01

merit) control armor performance and how these properties are controlled/ influenced by intrinsic (crystal structure, phase transitions, and single...reproducibility uncertainties (estimates of precision) could be quantified and also identify key parameters that should be controlled in SHPB/Kolsky testing...control performance? Are there figures of merit? How are the mechanical properties influenced by intrinsic and extrinsic material characteristics

Speech and Pause Characteristics in Multiple Sclerosis: A Preliminary Study of Speakers with High and Low Neuropsychological Test Performance

ERIC Educational Resources Information Center

Feenaughty, Lynda; Tjaden, Kris; Benedict, Ralph H. B.; Weinstock-Guttman, Bianca

2013-01-01

This preliminary study investigated how cognitive-linguistic status in multiple sclerosis (MS) is reflected in two speech tasks (i.e. oral reading, narrative) that differ in cognitive-linguistic demand. Twenty individuals with MS were selected to comprise High and Low performance groups based on clinical tests of executive function and information…

High subsonic flow tests of a parallel pipe followed by a large area ratio diffuser

NASA Technical Reports Server (NTRS)

Barna, P. S.

1975-01-01

Experiments were performed on a pilot model duct system in order to explore its aerodynamic characteristics. The model was scaled from a design projected for the high speed operation mode of the Aircraft Noise Reduction Laboratory. The test results show that the model performed satisfactorily and therefore the projected design will most likely meet the specifications.

Relationships between maximal strength of lower limb, anthropometric characteristics and fundamental explosive performance in handball players.

PubMed

Hermassi, Souhail; Chelly, Mohamed Souhaiel; Wagner, Herbert; Fieseler, Georg; Schulze, Stephan; Delank, Karl-Stefan; Shephard, Roy J; Schwesig, René

2018-02-14

 The purpose of this study was to examine relationships between lower body muscular strength, anthropometric characteristics and several measures of explosive performance in elite team-handball players.  22 male elite team-handball players (age: 19.1 ± 1.7 years) were studied during the competitive season. Standard anthropometric and body composition measures included body mass index, lower limb and thigh muscle volume, and body fat percentage. Maximal leg strength was determined by a one-repetition maximum (1-RM) half back-squat. Vertical jump performance was assessed using a squat jump (SJ) and a counter movement jump (CMJ). Repeated shuttle-sprint ability (RSA) was tested by 6 (2 × 15 m) shuttle sprints with 20 s of active recovery intervals. The best time in a single shuttle sprint (30m; RSA best ), fastest total time (RSA TT ) and RSA test performance decrement (RSA dec ) were recorded. Agility was measured using a modified T-half test (MAT). Throwing velocities of jump shooting and 3-step throwing were recorded by digital video camera.  The explained variance of 1-RM half-back-squats ranged from 0.2 % (RSA% Fatigue Index) to 70.1 % (CMJ). Four out of 8 variables (RSA Best Time, CMJ, SJ, throwing velocity of jump shoot) demonstrated an r 2  > 0.5. Jump performances seemed closely related to 1-RM half-back-squats. Furthermore, 1-RM half-back-squats were positively correlated with leg and thigh muscle volumes (r = 0.652, r = 0.768).  The anthropometric characteristics and some physical performance tests are closely related to the maximal strength performance of handball players. Coaches should focus on maximal strength training programs for the lower limbs when seeking improvements in the throwing velocity and jump performance of handball players. © Georg Thieme Verlag KG Stuttgart · New York.

Baseline experimental investigation of an electrohydrodynamically assisted heat pipe

NASA Technical Reports Server (NTRS)

Duncan, A. B.

1995-01-01

The increases in power demand and associated thermal management requirements of future space programs such as potential Lunar/Mars missions will require enhancing the operating efficiencies of thermal management devices. Currently, the use of electrohydrodynamically (EHD) assisted thermal control devices is under consideration as a potential method of increasing thermal management system capacity. The objectives of the currently described investigation included completing build-up of the EHD-Assisted Heat Pipe Test bed, developing test procedures for an experimental evaluation of the unassisted heat pipe, developing an analytical model capable of predicting the performance limits of the unassisted heat pipe, and obtaining experimental data which would define the performance characteristics of the unassisted heat pipe. The information obtained in the currently proposed study will be used in order to provide extensive comparisons with the EHD-assisted performance observations to be obtained during the continuing investigation of EHD-Assisted heat transfer devices. Through comparisons of the baseline test bed data and the EHD assisted test bed data, accurate insight into the performance enhancing characteristics of EHD augmentation may be obtained. This may lead to optimization, development, and implementation of EHD technology for future space programs.

Better diagnostic accuracy of neuropathy in obesity: A new challenge for neurologists.

PubMed

Callaghan, Brian C; Xia, Rong; Reynolds, Evan; Banerjee, Mousumi; Burant, Charles; Rothberg, Amy; Pop-Busui, Rodica; Villegas-Umana, Emily; Feldman, Eva L

2018-03-01

To determine the comparative diagnostic characteristics of neuropathy measures in an obese population. We recruited obese participants from the University of Michigan's Weight Management Program. Receiver operative characteristic analysis determined the area under the curve (AUC) of neuropathy measures for distal symmetric polyneuropathy (DSP), small fiber neuropathy (SFN), and cardiovascular autonomic neuropathy (CAN). The best test combinations were determined using stepwise and Score subset selection models. We enrolled 120 obese participants. For DSP, seven of 42 neuropathy measures (Utah Early Neuropathy Score (UENS, N = 62), Michigan Neuropathy Screening Instrument (MNSI) reduced combined index, MNSI examination, nerve fiber density (NFD) leg, tibial F response, MNSI questionnaire, peroneal distal motor latency) had AUCs ≥ 0.75. Three of 19 small fiber nerve measures for SFN (UENS, NFD leg, Sudoscan feet (N = 70)) and zero of 16 CAN measures had AUCs ≥ 0.75. Combinations of tests performed better than individual tests with AUCs of 0.82 for DSP (two parameters) and 0.84 for SFN (three parameters). Many neuropathy measures demonstrate good test performance for DSP in obese participants. Select few small fiber nerve measures performed well for SFN, and none for CAN. Specific combinations of tests should be used for research studies to maximize diagnostic performance in obese cohorts. Published by Elsevier B.V.

Multicenter Pivotal Clinical Trial of Urine Malaria Test for Rapid Diagnosis of Plasmodium falciparum Malaria

PubMed Central

Ezeigwe, Nnenna; Ntadom, Godwin; Oladosu, Oladipo O.; Rainwater-Loveth, Kaitlin; O'Meara, Wendy; Okpokoro, Evaezi; Brieger, William

2016-01-01

ABSTRACT The need to expand malaria diagnosis capabilities alongside policy requirements for mandatory testing before treatment motivates exploration of noninvasive rapid diagnostic tests (RDTs). We report the outcome of the first cross-sectional, single-blind clinical performance evaluation of a urine malaria test (UMT) for diagnosis of Plasmodium falciparum malaria in febrile patients. Matched urine and finger-prick blood samples from participants ≥2 years of age with fever (axillary temperature of ≥37.5°C) or with a history of fever in the preceding 48 h were tested with UMT and microscopy (as the gold standard). BinaxNOW (Pf and Pan versions) blood RDTs were done to assess relative performance. Urinalysis and rheumatoid factor (RF) tests were conducted to evaluate possible interference. Diagnostic performance characteristics were computed at 95% confidence intervals (CIs). Of 1,800 participants screened, 1,691 were enrolled; of these 566 (34%) were febrile, and 1,125 (66%) were afebrile. Among enrolled participants, 341 (20%) tested positive by microscopy, 419 (25%) were positive by UMT, 676 (40%) were positive by BinaxNOW Pf, and 368 (22%) were positive by BinaxNow Pan. UMT sensitivity among febrile patients (for whom the test was indicated) was 85%, and specificity was 84%. Among febrile children ≤5 years of age, UMT sensitivity was 93%, and specificity was 83%. The area under the receiver-operator characteristic curve (AUC) of UMT (0.84) was not significantly different from that of BinaxNOW Pf (0.86) or of BinaxNOW Pan (0.87), indicating that the tests do not differ in overall performance. Gender, seasons, and RF did not impact UMT performance. Leukocytes, hematuria, and urobilinogen concentrations in urine were associated with lower UMT specificities. UMT performance was comparable to that of the BinaxNOW Pf/Pan tests, making UMT a promising tool to expand malaria testing in public and private health care settings where there are challenges to blood-based malaria diagnosis testing. PMID:27847373

Space Shuttle Plume and Plume Impingement Study

NASA Technical Reports Server (NTRS)

Tevepaugh, J. A.; Penny, M. M.

1977-01-01

The extent of the influence of the propulsion system exhaust plumes on the vehicle performance and control characteristics is a complex function of vehicle geometry, propulsion system geometry, engine operating conditions and vehicle flight trajectory were investigated. Analytical support of the plume technology test program was directed at the two latter problem areas: (1) definition of the full-scale exhaust plume characteristics, (2) application of appropriate similarity parameters; and (3) analysis of wind tunnel test data. Verification of the two-phase plume and plume impingement models was directed toward the definition of the full-scale exhaust plume characteristics and the separation motor impingement problem.

Repeat GED[R] Tests Examinees: Who Persists and Who Passes? GED Testing Service [R]Research Studies, 2010-2

ERIC Educational Resources Information Center

Zhang, Jizhi; Patterson, Margaret Becker

2010-01-01

Like most high-stakes testing programs, the GED[R] testing program allows examinees who do not pass on the first attempt to retake the GED Tests. Studies and reports have described GED Tests candidates' characteristics and testing performance, but no study has targeted repeat examinees. A series of questions related to repeat examinees remains…

Test data report, low speed wind tunnel tests of a full scale lift/cruise-fan inlet, with engine, at high angles of attack

NASA Technical Reports Server (NTRS)

Shain, W. M.

1978-01-01

A low speed wind tunnel test of a fixed lip inlet with engine, was performed. The inlet was close coupled to a Hamilton Standard 1.4 meter, variable pitch fan driven by a lycoming T55-L-11A engine. Tests were conducted with various combinations of inlet angle of attack freestream velocities, and fan airflows. Data were recorded to define the inlet airflow separation boundaries, performance characteristics, and fan blade stresses. The test model, installation, instrumentation, test, data reduction and final data are described.

High Performance Concrete (HPC) bridge project for SR 43.

DOT National Transportation Integrated Search

2012-10-01

The objective of this research was to develop and test high performance concrete mixtures, made of locally available materials, having : durability characteristics that far exceed those of conventional concrete mixtures. Based on the results from the...

Comparison of body composition, heart rate variability, aerobic and anaerobic performance between competitive cyclists and triathletes

PubMed Central

Arslan, Erşan; Aras, Dicle

2016-01-01

[Purpose] The aim of this study was to compare the body composition, heart rate variability, and aerobic and anaerobic performance between competitive cyclists and triathletes. [Subjects] Six cyclists and eight triathletes with experience in competitions voluntarily participated in this study. [Methods] The subjects’ body composition was measured with an anthropometric tape and skinfold caliper. Maximal oxygen consumption and maximum heart rate were determined using the incremental treadmill test. Heart rate variability was measured by 7 min electrocardiographic recording. The Wingate test was conducted to determine anaerobic physical performance. [Results] There were significant differences in minimum power and relative minimum power between the triathletes and cyclists. Anthropometric characteristics and heart rate variability responses were similar among the triathletes and cyclists. However, triathletes had higher maximal oxygen consumption and lower resting heart rates. This study demonstrated that athletes in both sports have similar body composition and aerobic performance characteristics. PMID:27190476

Design and manufacture of wheels for a dual-mode (manned - automatic) lunar surface roving vehicle. Volume 2: Proposed test plan

NASA Technical Reports Server (NTRS)

1970-01-01

A developmental test plan for the wheel and wheel drive assembly of the dual-mode (manned/automated) lunar surface roving vehicle is presented. The tests cover performance, as well as critical environmental characteristics. Insofar as practical, the environmental conditions imposed will be in the sequence expected during the hardware's life from storage through the lunar mission. Test procedures are described for static load deflection and endurance tests. Soft soil tests to determine mobility characteristics including drawbar-pull and thrust vs slip, and motion resistance for various wheel loads are also discussed. Test designs for both ambient and thermal vacuum conditions are described. Facility, transducer, and instrumentation requirements are outlined.

A suite of phantom-based test methods for assessing image quality of photoacoustic tomography systems

NASA Astrophysics Data System (ADS)

Vogt, William C.; Jia, Congxian; Wear, Keith A.; Garra, Brian S.; Pfefer, T. Joshua

2017-03-01

As Photoacoustic Tomography (PAT) matures and undergoes clinical translation, objective performance test methods are needed to facilitate device development, regulatory clearance and clinical quality assurance. For mature medical imaging modalities such as CT, MRI, and ultrasound, tissue-mimicking phantoms are frequently incorporated into consensus standards for performance testing. A well-validated set of phantom-based test methods is needed for evaluating performance characteristics of PAT systems. To this end, we have constructed phantoms using a custom tissue-mimicking material based on PVC plastisol with tunable, biologically-relevant optical and acoustic properties. Each phantom is designed to enable quantitative assessment of one or more image quality characteristics including 3D spatial resolution, spatial measurement accuracy, ultrasound/PAT co-registration, uniformity, penetration depth, geometric distortion, sensitivity, and linearity. Phantoms contained targets including high-intensity point source targets and dye-filled tubes. This suite of phantoms was used to measure the dependence of performance of a custom PAT system (equipped with four interchangeable linear array transducers of varying design) on design parameters (e.g., center frequency, bandwidth, element geometry). Phantoms also allowed comparison of image artifacts, including surface-generated clutter and bandlimited sensing artifacts. Results showed that transducer design parameters create strong variations in performance including a trade-off between resolution and penetration depth, which could be quantified with our method. This study demonstrates the utility of phantom-based image quality testing in device performance assessment, which may guide development of consensus standards for PAT systems.

Predictors of retest effects in a longitudinal study of cognitive aging in a diverse community-based sample

PubMed Central

Gross, Alden L.; Benitez, Andreana; Shih, Regina; Bangen, Katherine J.; Glymour, M Maria M; Sachs, Bonnie; Sisco, Shannon; Skinner, Jeannine; Schneider, Brooke C.; Manly, Jennifer J.

2016-01-01

OBJECTIVE Better performance due to repeated testing can bias long-term trajectories of cognitive aging and correlates of change. We examined whether retest effects differ as a function of individual differences pertinent to cognitive aging: race/ethnicity, age, sex, language, years of education, and dementia risk factors including APOE ε4 status, baseline cognitive performance, and cardiovascular risk. METHOD We used data from the Washington Heights-Inwood Columbia Aging Project, a community-based cohort of older adults (n=4,073). We modeled cognitive change and retest effects in summary factors for general cognitive performance, memory, executive functioning, and language using multilevel models. Retest effects were parameterized in two ways, as improvement between the first and subsequent testings, and as the square root of the number of prior testings. We evaluated whether the retest effect differed by individual characteristics. RESULTS The mean retest effect for general cognitive performance was 0.60 standard deviations (95%CI: 0.46, 0.74), and was similar for memory, executive functioning, and language. Retest effects were greater for participants in the lowest quartile of cognitive performance, consistent with regression to the mean. Retest did not differ by other characteristics. CONCLUSIONS Retest effects are large in this community-based sample, but do not vary by demographic or dementia-related characteristics. Differential retest effects may not limit the generalizability of inferences across different groups in longitudinal research. PMID:26527240

Combustion-chamber Performance Characteristics of a Python Turbine-propeller Engine Investigated in Altitude Wind Tunnel

NASA Technical Reports Server (NTRS)

Campbell, Carl E

1951-01-01

Combustion-chamber performance characteristics of a Python turbine-propeller engine were determined from investigation of a complete engine over a range of engine speeds and shaft horsepowers at simulated altitudes. Results indicated the effect of engine operating conditions and altitude on combustion efficiency and combustion-chamber total pressure losses. Performance of this vaporizing type combustion chamber was also compared with several atomizing type combustion chambers. Over the range of test conditions investigated, combustion efficiency varied from approximately 0.95 to 0.99.

Do governance, equity characteristics, and venture capital nvolvement affect long-term wealth creation in U.S. health care and biotechnology IPOs?

PubMed

Williams, David R; Duncan, W Jack; Ginter, Peter M; Shewchuk, Richard M

2006-01-01

Agency theory remains the dominant means of examining governance issues and ownership characteristics related to large organizations. Research in these areas within large organizations has increased our understanding, yet little is known about the influence that these mechanisms and characteristics have had on IPO firm performance. This study tests an agency perspective that venture capital involvement, governance and equity characteristics affect health care and biotechnology IPO firm performance. Our results indicate that there is no correlation between these factors and health care and biotechnology IPO wealth creation. For these entrepreneurs, our findings suggest a contingent approach for the use of these mechanisms.

Specific smartphone usage and cognitive performance affect gait characteristics during free-living and treadmill walking.

PubMed

Niederer, Daniel; Bumann, Anke; Mühlhauser, Yvonne; Schmitt, Mareike; Wess, Katja; Engeroff, Tobias; Wilke, Jan; Vogt, Lutz; Banzer, Winfried

2018-05-01

Mobile phone tasks like texting, typing, and dialling during walking are known to impact gait characteristics. Beyond that, the effects of performing smartphone-typical actions like researching and taking self-portraits (selfie) on gait have not been investigated yet. We aimed to investigate the effects of smartphone usage on relevant gait characteristics and to reveal potential association of basic cognitive and walking plus smartphone dual-task abilities. Our cross-sectional, cross-over study on physically active, healthy participants was performed on two days, interrupted by a 24-h washout in between. Assessments were: 1) Cognitive testing battery consisting of the trail making test (TMT A and B) and the Stroop test 2) Treadmill walking under five smartphone usage conditions: no use (control condition), reading, dialling, internet searching and taking a selfie in randomized order. Kinematic and kinetic gait characteristics were assessed to estimate conditions influence. In our sample of 36 adults (24.6 ± 1 years, 23 female, 13 male), ANCOVAs followed by post-hoc t-tests revealed that smartphone usage impaired all tested gait characteristics: gait speed (decrease, all conditions): F = 54.7, p < 0.001; cadence (increase, all): F = 38.3, p < 0.001; double stride length (decrease, all): F = 33.8, p < 0.001; foot external rotation (increase during dialling, researching, selfie): F = 16.7, p < 0.001; stride length variability (increase): F = 11.7, p < 0.001; step width variability (increase): F = 5.3, p < 0.001; step width (Friedmann test and Wilcoxon Bonferroni-Holm-corrected post-hoc analyses, increase): Z = -2.3 to -2.9; p < 0.05); plantar pressure proportion (increase during reading and researching) (Z = -2.9; p < 0.01). The ability to keep usual gait quality during smartphone usage was systematically associated with the TMT B time regarding cadence and double stride length for reading (r = -0.37), dialling (r = -0.35) and taking a selfie (r = -0.34). Smartphone usage substantially impacts walking characteristics in most situations. Changes of gait patterns indicate higher cognitive loads and lower awareness. Copyright © 2018 Elsevier B.V. All rights reserved.

Performance Characteristics of 1977 Ford 300 CID Engine

DOT National Transportation Integrated Search

1980-02-01

Experimental data were obtained in dynamometer tests of a 1977 Ford 300 CID engine to determine fuel consumption and emissions (hydrocarbons, carbon monoxide, and oxides of Nitrogen) at steady-state engine operating modes. The objective of the test w...

Evaluation of the Shuttle GN&C during powered ascent flight phase. [Guidance Navigation and Control equipment system design and flight tests

NASA Technical Reports Server (NTRS)

Olson, L.; Sunkel, J. W.

1982-01-01

An overview of the ascent trajectory and GN&C (guidance, navigation, and control) system design is followed by a summary of flight test results for the ascent phase of STS-1. The most notable variance from nominal pre-flight predictions was the lofted trajectory observed in first stage due to an unanticipated shift in pitch aerodynamic characteristics from those predicted by wind tunnel tests. The GN&C systems performed as expected on STS-1 throughout powered flight. Following a discussion of the software constants changed for Flight 2 to provide adequate performance margin, a summary of test results from STS-2 and STS-3 is presented. Vehicle trajectory response and GN&C system behavior were very similar to STS-1. Ascent aerodynamic characteristics extracted from the first two test flights were included in the data base used to design the first stage steering and pitch trim profiles for STS-3.

Current Testing Capabilities at the NASA Ames Ballistic Ranges

NASA Technical Reports Server (NTRS)

Ramsey, Alvin; Tam, Tim; Bogdanoff, David; Gage, Peter

1999-01-01

Capabilities for designing and performing ballistic range tests at the NASA Ames Research Center are presented. Computational tools to assist in designing and developing ballistic range models and to predict the flight characteristics of these models are described. A CFD code modeling two-stage gun performance is available, allowing muzzle velocity, maximum projectile base pressure, and gun erosion to be predicted. Aerodynamic characteristics such as drag and stability can be obtained at speeds ranging from 0.2 km/s to 8 km/s. The composition and density of the test gas can be controlled, which allows for an assessment of Reynolds number and specific heat ratio effects under conditions that closely match those encountered during planetary entry. Pressure transducers have been installed in the gun breech to record the time history of the pressure during launch, and pressure transducers have also been installed in the walls of the range to measure sonic boom effects. To illustrate the testing capabilities of the Ames ballistic ranges, an overview of some of the recent tests is given.

Comparison of Thermal Performance Characteristics of Ammonia and Propylene Loop Heat Pipes

NASA Technical Reports Server (NTRS)

Kaya, Tarik; Baker, Charles; Ku, Jentung

2000-01-01

In this paper, experimental work performed on a breadboard Loop Heat Pipe (LHP) is presented. The test article was built by DCI for the Geoscience Laser Altimeter System (GLAS) instrument on the ICESat spacecraft. The thermal system requirements of GLAS have shown that ammonia cannot be used as the working fluid in this LHP because GLAS radiators could cool to well below the freezing point of ammonia. As a result, propylene was proposed as an alternative LHP working fluid since it has a lower freezing point than ammonia. Both working fluids were tested in the same LHP following a similar test plan in ambient conditions. The thermal performance characteristics of ammonia and propylene LHP's were then compared. In general, the propylene LHP required slightly less startup superheat 5nd less control heater power than the ammonia LHP, The thermal conductance values for the propylene LHP were also lower than the ammonia LHP. Later, the propylene LHP was tested in a thermal vacuum chamber. These tests demonstrated that propylene could meet the GLAS thermal design requirements. Design guidelines were proposed for the next flight-like Development Model (DM) LHP for thermal control of the GLAS instrument.

Performance test results of 80 K centrifugal compressor for helium refrigerator

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

Asakura, H.; Kato, D.; Saji, N.

1994-12-31

The authors have developed a completely oil-free compressor used for the highly reliable helium refrigeration system for a superconducting generator and carried out performance tests under actual condition. The compressor is designed to achieve a pressure ratio of 8 with only 4 stages by cooling the compressor inlet at 80 K with liquid nitrogen, thus acquiring high reliability of long-term maintenance-free operation together with the use of magnetic bearings for oil-free operation. The compressor at each stage is independently driven by a 25 kW built-in motor at the speed of 100,000 rpm, with the power supplied by a variable frequencymore » inverter. The performance test was carried out at each stage, by incorporating the compressor in the closed loop test equipment using helium gas. It was recognized from the test results that the specified pressure ratio of each stage was achieved at the speed below the rated one of 100,000 rpm. It was found that each stage of the compressor has a flat characteristics of adiabatic efficiency over the wide flow range. The mechanical rotation characteristics at low temperatures was also confirmed to be sufficiently stable.« less

Transparent superstrate terrestrial solar cell module

NASA Technical Reports Server (NTRS)

1977-01-01

The design, development, fabrication, and testing of the transparent solar cell module were examined. Cell performance and material process characteristics were determined by extensive tests and design modifications were made prior to preproduction fabrication. These tests included three cell submodules and two full size engineering modules. Along with hardware and test activity, engineering documentation was prepared and submitted.

Low-cost thin-film absorber/evaporator for an absorption chiller. Final report, May 1992-April 1993

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

Lowenstein, A.; Sibilia, M.

1993-04-01

The feasibility of making the absorber and evaporator of a small lithium-bromide absorption chiller from thin plastic films was studied. Tests were performed to measure (1) pressure limitations for a plastic thin-film heat exchanger, (2) flow pressure-drop characteristics, (3) air permeation rates across the plastic films, and (4) creep characteristics of the plastic films. Initial tests were performed on heat exchangers made of either low-density polyethylene (LDPE), high-density polyethylene (HDPE), or a LDPE/HDPE blend. While initial designs for the heat exchanger failed at internal pressures of only 5 to 6 psi, the final design could withstand pressures of 34 psi.

Test results of JPL LiSOCl sub 2 cells

NASA Technical Reports Server (NTRS)

Halpert, G.; Subbarao, S.; Dawson, S.; Ang, V.; Deligiannis, E.

1986-01-01

In the development of high rate Li-SO-Cl2 cells for various applications, the goal is to achieve 300 watt-hours per kilogram at the C/2 (5 amp) rate in a D cell configuration. The JPL role is to develop the understanding of the performance, life, and safety limiting characteristics in the cell and to transfer the technology to a manufacturer to produce a safe, high quality product in a reproducible manner. The approach taken to achieve the goals is divided into four subject areas: cathode processes and characteristics; chemical reactions and safety; cell design and assembly; and performance and abuse testing. The progress made in each of these areas is discussed.

Tests of two new polyurethane foam wheelchair tires.

PubMed

Gordon, J; Kauzlarich, J J; Thacker, J G

1989-01-01

The performance characteristics of four 24-inch wheelchair tires are considered; one pneumatic and three airless. Specifically, two new airless polyurethane foam tires (circular and tapered cross-section) were compared to both a molded polyisoprene tire and a rubber pneumatic tire. Rolling resistance, coefficient of static friction, spring rate, tire roll-off, impact absorption, wear resistance, and resistance to compression set were the characteristics considered for the basis of comparison. Although the pneumatic tire is preferred by many wheelchair users, the two new polyurethane foam tires were found to offer a performance similar to the high-pressure pneumatic tire. In addition, the foam tires are less expensive and lighter in weight than the other tires tested.

Experimental study of the seismic performance of L-shaped columns with 500 MPa steel bars.

PubMed

Wang, Tiecheng; Liu, Xiao; Zhao, Hailong

2014-01-01

Based on tests on six L-shaped RC columns with 500 MPa steel bars, the effect of axial compression ratios and stirrup spacing on failure mode, bearing capacity, displacement, and curvature ductility of the specimens is investigated. Test results show that specimens with lower axial load and large stirrup characteristic value (larger than about 0.35) are better at ductility and seismic performance, while specimens under high axial load or with a small stirrup characteristic value (less than about 0.35) are poorer at ductility; L-shaped columns with 500 MPa steel bars show better bearing capacity and ductility in comparison with specimens with HRB400 steel bars.

Viscoelastic properties of elastomeric materials for O-ring applications

NASA Technical Reports Server (NTRS)

Bower, Mark V.

1989-01-01

Redesign of the Space Shuttle Solid Rocket Booster necessitated re-evaluation of the material used in the field joint O-ring seals. This research project was established to determine the viscoelastic characteristics of five candidate materials. The five materials are: two fluorocarbon compounds, two nitrile compounds, and a silicon compound. The materials were tested in a uniaxial compression test to determine the characteristic relaxation functions. These tests were performed at five different temperatures. A master material curve was developed for each material from the experimental data. The results of this study are compared to tensile relaxation tests. Application of these results to the design analysis is discussed in detail.

Evaluation of the Langley 4- by 7-meter tunnel for propeller noise measurements

NASA Technical Reports Server (NTRS)

Block, P. J. W.; Gentry, G. L., Jr.

1984-01-01

An experimental and theoretical evaluation of the Langley 4- by 7- Meter Tunnel was conducted to determine its suitability for obtaining propeller noise data. The tunnel circuit and open test section are described. An experimental evaluation is performed using microphones placed in and on the tunnel floor. The reflection characteristics and background noise are determined. The predicted source (propeller) near-field/far-field boundary is given using a first-principles method. The effect of the tunnel-floor boundry layer on the noise from the propeller is also predicted. A propeller test stand used for part of his evaluation is also described. The measured propeller performance characteristics are compared with those obtained at a larger scale, and the effect of the test-section configuration on the propeller performance is examined. Finally, propeller noise measurements were obtained on an eight-bladed SR-2 propeller operating at angles of attack -8 deg, 0 deg, and 4.6 deg to give an indication of attainable signal-to-noise ratios.

Assessing sorbent injection mercury control effectiveness in flue gas streams

USGS Publications Warehouse

Carey, T.R.; Richardson, C.F.; Chang, R.; Meserole, F.B.; Rostam-Abadi, M.; Chen, S.

2000-01-01

One promising approach for removing mercury from coal-fired, utility flue gas involves the direct injection of mercury sorbents. Although this method has been effective at removing mercury in municipal waste incinerators, tests conducted to date on utility coal-fired boilers show that mercury removal is much more difficult in utility flue gas. EPRI is conducting research to investigate mercury removal using sorbents in this application. Bench-scale, pilot-scale, and field tests have been conducted to determine the ability of different sorbents to remove mercury in simulated and actual flue gas streams. This paper focuses on recent bench-scale and field test results evaluating the adsorption characteristics of activated carbon and fly ash and the use of these results to develop a predictive mercury removal model. Field tests with activated carbon show that adsorption characteristics measured in the lab agree reasonably well with characteristics measured in the field. However, more laboratory and field data will be needed to identify other gas phase components which may impact performance. This will allow laboratory tests to better simulate field conditions and provide improved estimates of sorbent performance for specific sites. In addition to activated carbon results, bench-scale and modeling results using fly ash are presented which suggest that certain fly ashes are capable of adsorbing mercury.

Grindability measurements on low-rank fuels. [Prediction of large pulverizer performance from small scale test equipment

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

Peipho, R.R.; Dougan, D.R.

1981-01-01

Experience has shown that the grinding characteristics of low rank coals are best determined by testing them in a pulverizer. Test results from a small MPS-32 Babcock and Wilcox pulverizer to predict large, full-scale pulverizer performance are presented. The MPS-32 apparatus, test procedure and evaluation of test results is described. The test data show that the Hardgrove apparatus and the ASTM test method must be used with great caution when considering low-rank fuels. The MPS-32 meets the needs for real-machine simulation but with some disadvantages. A smaller pulverizer is desirable. 1 ref.

Skidding Coefficients on an Alluvial Soil

Treesearch

W. N. Darwin

1965-01-01

The Southern Hardwoods Laboratory is studying the influence of ground conditions and load characteristics on the performance of skidding vehicles in southern bottom lands. The exploratory test was aimed at evaluating the effects of bark on skidding coefficients, but it also yielded information on other log characteristics and on effects of soil moisture.

Space shuttle orbit maneuvering engine

NASA Technical Reports Server (NTRS)

Pauckert, R. P.

1975-01-01

Data on the performance, stability, and thermal characteristics of an OME operating with an alternate injector configuration and with alternate propellants was obtained. The design, manufacturing, and operating characteristics of an electroformed, regeneratively cooled thrust chamber were also derived. Subscale and full scale tests provide data relating to off-design and transient operation.

High Ability and Learner Characteristics

ERIC Educational Resources Information Center

Hindal, Huda; Reid, Norman; Whitehead, Rex

2013-01-01

The outstandingly able learner has been conceptualised, in terms of test and examination performance, as the learner showing superior academic performance which is markedly better than that of peers and in ways regarded as of value by wider society. In Kuwait, such superior examination performance leads to a classification regarded as being…

Nuclear Cryogenic Propulsion Stage (NCPS) Fuel Element Testing in the Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

NASA Technical Reports Server (NTRS)

Emrich, William J., Jr.

2017-01-01

To support the on-going nuclear thermal propulsion effort, a state-of-the-art non nuclear experimental test setup has been constructed to evaluate the performance characteristics of candidate fuel element materials and geometries in representative environments. The facility to perform this testing is referred to as the Nuclear Thermal Rocket Element Environment Simulator (NTREES). Last year NTREES was successfully used to satisfy a testing milestone for the Nuclear Cryogenic Propulsion Stage (NCPS) project and met or exceeded all required objectives.

Measuring the performance of telephone-based disease surveillance systems in local health departments.

PubMed

Dausey, David J; Chandra, Anita; Schaefer, Agnes G; Bahney, Ben; Haviland, Amelia; Zakowski, Sarah; Lurie, Nicole

2008-09-01

We tested telephone-based disease surveillance systems in local health departments to identify system characteristics associated with consistent and timely responses to urgent case reports. We identified a stratified random sample of 74 health departments and conducted a series of unannounced tests of their telephone-based surveillance systems. We used regression analyses to identify system characteristics that predicted fast connection with an action officer (an appropriate public health professional). Optimal performance in consistently connecting callers with an action officer in 30 minutes or less was achieved by 31% of participating health departments. Reaching a live person upon dialing, regardless of who that person was, was the strongest predictor of optimal performance both in being connected with an action officer and in consistency of connection times. Health departments can achieve optimal performance in consistently connecting a caller with an action officer in 30 minutes or less and may improve performance by using a telephone-based disease surveillance system in which the phone is answered by a live person at all times.

Integrated Vehicle Ground Vibration Testing in Support of Launch Vehicle Loads and Controls Analysis

NASA Technical Reports Server (NTRS)

Askins, Bruce R.; Davis, Susan R.; Salyer, Blaine H.; Tuma, Margaret L.

2008-01-01

All structural systems possess a basic set of physical characteristics unique to that system. These unique physical characteristics include items such as mass distribution and damping. When specified, they allow engineers to understand and predict how a structural system behaves under given loading conditions and different methods of control. These physical properties of launch vehicles may be predicted by analysis or measured by certain types of tests. Generally, these properties are predicted by analysis during the design phase of a launch vehicle and then verified by testing before the vehicle becomes operational. A ground vibration test (GVT) is intended to measure by test the fundamental dynamic characteristics of launch vehicles during various phases of flight. During the series of tests, properties such as natural frequencies, mode shapes, and transfer functions are measured directly. These data will then be used to calibrate loads and control systems analysis models for verifying analyses of the launch vehicle. NASA manned launch vehicles have undergone ground vibration testing leading to the development of successful launch vehicles. A GVT was not performed on the inaugural launch of the unmanned Delta III which was lost during launch. Subsequent analyses indicated had a GVT been performed, it would have identified instability issues avoiding loss of the vehicle. This discussion will address GVT planning, set-up, execution and analyses, for the Saturn and Shuttle programs, and will also focus on the current and on-going planning for the Ares I and V Integrated Vehicle Ground Vibration Test (IVGVT).

Characteristics of Subcooled Liquid Methane During Passage Through a Spray-Bar Joule-Thompson Thermodynamic Vent System

NASA Technical Reports Server (NTRS)

Hastings, L. J.; Bolshinskiy, L. G.; Hedayat, A.; Schnell, A.

2011-01-01

NASA s Marshall Space Flight Center (MSFC) conducted liquid methane (LCH4) testing in November 2006 using the multipurpose hydrogen test bed (MHTB) outfitted with a spray-bar thermodynamic vent system (TVS). The basic objective was to identify any unusual or unique thermodynamic characteristics associated with subcooled LCH4 that should be considered in the design of space-based TVSs. Thirteen days of testing were performed with total tank heat loads ranging from 720 W to 420 W at a fill level of approximately 90%. During an updated evaluation of the data, it was noted that as the fluid passed through the Joule Thompson expansion, thermodynamic conditions consistent with the pervasive presence of metastability were indicated. This paper describes the observed thermodynamic conditions that correspond with metastability and effects on TVS performance.

Design, fabrication, test, qualification, and price analysis of third generation design solar cell modules

NASA Technical Reports Server (NTRS)

1981-01-01

The fabrication of solar cell modules is detailed with emphasis upon laminating and interconnecting the panels that hold the simicrystalline silicon cells. Design problems and enviromental tests are described as well as performance characteristics.

Runflat Testing

DTIC Science & Technology

2015-09-09

guidance and procedures for testing the performance characteristics of runflat tires as equipped on ground vehicles. 15. SUBJECT TERMS runflat... tire assembly tread life combat flat central tire inflation system (CTIS) 16. SECURITY CLASSIFICATION OF: 17. LIMITATION...3 3.4 Tire Assemblies ..................................................................... 3 3.5 Environmental

Performance Characteristics of 1977 General Motors 350 CID Engine

DOT National Transportation Integrated Search

1980-02-01

Experimental data were obtained in dynamometer tests of a 1977 GM 350 CID engine to determine fuel consumption and emissions (hydrocarbons, carbon monoxide, and oxides of nitrogen) at steady-state engine operating modes. The objective of the test was...

Performance Characteristics of 1977 American Motors 304 CID Engine

DOT National Transportation Integrated Search

1980-02-01

Experimental data were obtained in dynamometer tests of a 1977 AM 304 CID engine to determine fuel consumption and emissions (hydrocarbons, carbon monoxide, and oxides of nitrogen) at steady-state engine operating modes. The objective of the test was...

Performance characteristics of an isolated coannular plug nozzle at transonic speeds

NASA Technical Reports Server (NTRS)

Mercer, C. E.; Burley, J. R., II

1985-01-01

The Langley 16-Foot Transonic Tunnel was used to evaluate the performance characteristics of a coannular plug nozzle at static conditions (Mach number of 0) and at Mach numbers from 0.65 to 1.20. Jet total pressure ratio was varied from 1.0 (jet off) to 10.0. Thirty-seven configurations generated by the combination of three geometric variables - plug angle, shroud boattail length (fixed exit radius), and shroud extension length - were tested.

Fuel conservation evaluation of US Army helicopters. Part 5. Ah-1S flight testing. Final report, 31 July-21 September 1982

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

Todd, L.L.; Savage, R.T.; Vincent, R.L.

1983-01-01

The United States Army Aviation Engineering Flight Activity conducted level flight performance tests of the AH-1S (Prod) helicopter to provide data to determine the most fuel efficient operating conditions. Hot and cold weather test sites were used to extend the range of the advancing tip Mach number data to supplement existing AH-1S performance data. Preliminary analysis of non-dimensional data identifies the effects of compressibility on performance and shows a power penalty of as much as 6% at a high NR/theta. The power required characteristics determined by these tests can be combined with engine performance to determine the most fuel efficientmore » operating conditions.« less

Thermal Performance Comparison of Glass Microsphere and Perlite Insulation Systems for Liquid Hydrogen Storage Tanks

NASA Astrophysics Data System (ADS)

Sass, J. P.; Fesmire, J. E.; Nagy, Z. F.; Sojourner, S. J.; Morris, D. L.; Augustynowicz, S. D.

2008-03-01

A technology demonstration test project was conducted by the Cryogenics Test Laboratory at the Kennedy Space Center (KSC) to provide comparative thermal performance data for glass microspheres, referred to as bubbles, and perlite insulation for liquid hydrogen tank applications. Two identical 1/15th scale versions of the 3,200,000 liter spherical liquid hydrogen tanks at Launch Complex 39 at KSC were custom designed and built to serve as test articles for this test project. Evaporative (boil-off) calorimeter test protocols, including liquid nitrogen and liquid hydrogen, were established to provide tank test conditions characteristic of the large storage tanks that support the Space Shuttle launch operations. This paper provides comparative thermal performance test results for bubbles and perlite for a wide range of conditions. Thermal performance as a function of cryogenic commodity (nitrogen and hydrogen), vacuum pressure, insulation fill level, tank liquid level, and thermal cycles will be presented.

Thermodynamic performance testing of the orbiter flash evaporator system

NASA Technical Reports Server (NTRS)

Jaax, J. R.; Melgares, M. A.; Frahm, J. P.

1980-01-01

System level testing of the space shuttle orbiter's development flash evaporator system (FES) was performed in a thermal vacuum chamber capable of simulating ambient ascent, orbital, and entry temperature and pressure profiles. The test article included the evaporator assembly, high load and topping exhaust duct and nozzle assemblies, and feedwater supply assembly. Steady state and transient heat load, water pressure/temperature and ambient pressure/temperature profiles were imposed by especially designed supporting test hardware. Testing in 1978 verified evaporator and duct heater thermal design, determined FES performance boundaries, and assessed topping evaporator plume characteristics. Testing in 1979 combined the FES with the other systems in the orbiter active thermal control subsystem (ATCS). The FES met or exceeded all nominal and contingency performance requirements during operation with the integrated ATCS. During both tests stability problems were encountered during steady state operations which resulted in subsequent design changes to the water spray nozzle and valve plate assemblies.

X-38 V-132 Free Flight 2 (This is a video tape)

NASA Technical Reports Server (NTRS)

Bordano, Aldo J.

2000-01-01

Mr. Aldo Bordano will be presenting details of some of the JSC flight mechanics involvement in the X-38 testing program. Focus shall be on the parafoil system with regards its testing, performance analysis, and GN&C. An excellent example of a recent flight test at Dryden Flight Research Center shall be shown which portrays the system characteristics, sequencing, performance, and testing techniques. The intent is to inform the scientific and engineering communities about the developments in the X-38 parafoil program, as well as invite feedback on potential improvements in testing or systems.

Performance characteristics of the Cooper PC-9 centrifugal compressor

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

Foster, R.E.; Neely, R.F.

1988-06-30

Mathematical performance modeling of the PC-9 centrifugal compressor has been completed. Performance characteristics curves have never been obtained for them in test loops with the same degree of accuracy as for the uprated axial compressors and, consequently, computer modeling of the top cascade and purge cascades has been very difficult and of limited value. This compressor modeling work has been carried out in an attempt to generate data which would more accurately define the compressor's performance and would permit more accurate cascade modeling. A computer code, COMPAL, was used to mathematically model the PC-9 performance with variations in gas composition,more » flow ratios, pressure ratios, speed and temperature. The results of this effort, in the form of graphs, with information about the compressor and the code, are the subject of this report. Compressor characteristic curves are featured. 13 figs.« less

Analysis of the Shuttle Orbiter reinforced carbon-carbon oxidation protection system

NASA Technical Reports Server (NTRS)

Williams, S. D.; Curry, Donald M.; Chao, Dennis; Pham, Vuong T.

1994-01-01

Reusable, oxidation-protected reinforced carbon-carbon (RCC) has been successfully flown on all Shuttle Orbiter flights. Thermal testing of the silicon carbide-coated RCC to determine its oxidation characteristics has been performed in convective (plasma Arc-Jet) heating facilities. Surface sealant mass loss was characterized as a function of temperature and pressure. High-temperature testing was performed to develop coating recession correlations for predicting performance at the over-temperature flight conditions associated with abort trajectories. Methods for using these test data to establish multi-mission re-use (i.e., mission life) and single mission limits are presented.

Performance Characterization of the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) CCD Cameras

NASA Astrophysics Data System (ADS)

Joiner, R. K.; Kobayashi, K.; Winebarger, A. R.; Champey, P. R.

2014-12-01

The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a sounding rocket instrument which is currently being developed by NASA's Marshall Space Flight Center (MSFC) and the National Astronomical Observatory of Japan (NAOJ). The goal of this instrument is to observe and detect the Hanle effect in the scattered Lyman-Alpha UV (121.6nm) light emitted by the Sun's Chromosphere to make measurements of the magnetic field in this region. In order to make accurate measurements of this effect, the performance characteristics of the three on-board charge-coupled devices (CCDs) must meet certain requirements. These characteristics include: quantum efficiency, gain, dark current, noise, and linearity. Each of these must meet predetermined requirements in order to achieve satisfactory performance for the mission. The cameras must be able to operate with a gain of no greater than 2 e-/DN, a noise level less than 25e-, a dark current level which is less than 10e-/pixel/s, and a residual non-linearity of less than 1%. Determining these characteristics involves performing a series of tests with each of the cameras in a high vacuum environment. Here we present the methods and results of each of these performance tests for the CLASP flight cameras.

Impact of Breast Reader Assessment Strategy on mammographic radiologists' test reading performance.

PubMed

Suleiman, Wasfi I; Rawashdeh, Mohammad A; Lewis, Sarah J; McEntee, Mark F; Lee, Warwick; Tapia, Kriscia; Brennan, Patrick C

2016-06-01

The detection of breast cancer is somewhat limited by human factors, and thus there is a need to improve reader performance. This study assesses whether radiologists who regularly undertake the education in the form of the Breast Reader Assessment Strategy (BREAST) demonstrate any changes in mammography interpretation performance over time. In 2011, 2012 and 2013, 14 radiologists independently assessed a year-specific BREAST mammographic test-set. Radiologists read a different single test-set once each year, with each comprising 60 digital mammogram cases. Radiologists marked the location of suspected lesions without computer-aided diagnosis (CAD) and assigned a confidence rating of 2 for benign and 3-5 for malignant lesions. The mean sensitivity, specificity, location sensitivity, JAFROC FOM and ROC AUC were calculated. A Kruskal-Wallis test was used to compare the readings for the 14 radiologists across the 3 years. Wilcoxon signed rank test was used to assess comparison between pairs of years. Relationships between changes in performance and radiologist characteristics were examined using a Spearman's test. Significant increases were noted in mean sensitivity (P = 0.01), specificity (P = 0.01), location sensitivity (P = 0.001) and JAFROC FOM (P = 0.001) between 2011 and 2012. Between 2012 and 2013, significant improvements were noted in mean sensitivity (P = 0.003), specificity (P = 0.002), location sensitivity (P = 0.02), JAFROC FOM (P = 0.005) and ROC AUC (P = 0.008). No statistically significant correlations were shown between the levels of improvement and radiologists' characteristics. Radiologists' who undertake the BREAST programme demonstrate significant improvements in test-set performance during a 3-year period, highlighting the value of ongoing education through the use of test-set. © 2016 The Royal Australian and New Zealand College of Radiologists.

Performing a Large-Scale Modal Test on the B2 Stand Crane at NASA's Stennis Space Center

NASA Technical Reports Server (NTRS)

Stasiunas, Eric C.; Parks, Russel A.

2018-01-01

A modal test of NASA’s Space Launch System (SLS) Core Stage is scheduled to occur prior to propulsion system verification testing at the Stennis Space Center B2 test stand. A derrick crane with a 180-ft long boom, located at the top of the stand, will be used to suspend the Core Stage in order to achieve defined boundary conditions. During this suspended modal test, it is expected that dynamic coupling will occur between the crane and the Core Stage. Therefore, a separate modal test was performed on the B2 crane itself, in order to evaluate the varying dynamic characteristics and correlate math models of the crane. Performing a modal test on such a massive structure was challenging and required creative test setup and procedures, including implementing both AC and DC accelerometers, and performing both classical hammer and operational modal analysis. This paper describes the logistics required to perform this large-scale test, as well as details of the test setup, the modal test methods used, and an overview of the results.

Alkaline fuel cell performance investigation

NASA Technical Reports Server (NTRS)

Martin, R. E.; Manzo, M. A.

1988-01-01

An exploratory experimental fuel cell test program was conducted to investigate the performance characteristics of alkaline laboratory research electrodes. The objective of this work was to establish the effect of temperature, pressure, and concentration upon performance and evaluate candidate cathode configurations having the potential for improved performance. The performance characterization tests provided data to empirically establish the effect of temperature, pressure, and concentration upon performance for cell temperatures up to 300 F and reactant pressures up to 200 psia. Evaluation of five gold alloy cathode catalysts revealed that three doped gold alloys had more that two times the surface areas of reference cathodes and therefore offered the best potential for improved performance.

Alkaline fuel cell performance investigation

NASA Technical Reports Server (NTRS)

Martin, R. E.; Manzo, M. A.

1988-01-01

An exploratory experimental fuel cell test program was conducted to investigate the performance characteristics of alkaline laboratory research electrodes. The objective of this work was to establish the effect of temperature, pressure, and concentration upon performance and evaluate candidate cathode configurations having the potential for improved performance. The performance characterization tests provided data to empirically establish the effect of temperature, pressure, and concentration upon performance for cell temperatures up to 300 F and reactant pressures up to 200 psia. Evaluation of five gold alloy cathode catalysts revealed that three doped gold alloys had more than two times the surface areas of reference cathodes and therefore offered the best potential for improved performance.

A Flight Prediction for Performance of the SWAS Solar Array Deployment Mechanism

NASA Technical Reports Server (NTRS)

Seniderman, Gary; Daniel, Walter K.

1999-01-01

The focus of this paper is a comparison of ground-based solar array deployment tests with the on-orbit deployment. The discussion includes a summary of the mechanisms involved and the correlation of a dynamics model with ground based test results. Some of the unique characteristics of the mechanisms are explained through the analysis of force and angle data acquired from the test deployments. The correlated dynamics model is then used to predict the performance of the system in its flight application.

Performance Testing of a Photocatalytic Oxidation Module for Spacecraft Cabin Atmosphere Revitalization

NASA Technical Reports Server (NTRS)

Perry, Jay L.; Abney, Morgan B.; Frederick, Kenneth R.; Scott, Joseph P.; Kaiser, Mark; Seminara, Gary; Bershitsky, Alex

2011-01-01

Photocatalytic oxidation (PCO) is a candidate process technology for use in high volumetric flow rate trace contaminant control applications in sealed environments. The targeted application for PCO as applied to crewed spacecraft life support system architectures is summarized. Technical challenges characteristic of PCO are considered. Performance testing of a breadboard PCO reactor design for mineralizing polar organic compounds in a spacecraft cabin atmosphere is described. Test results are analyzed and compared to results reported in the literature for comparable PCO reactor designs.

Applying a social network analysis (SNA) approach to understanding radiologists' performance in reading mammograms

NASA Astrophysics Data System (ADS)

Tavakoli Taba, Seyedamir; Hossain, Liaquat; Heard, Robert; Brennan, Patrick; Lee, Warwick; Lewis, Sarah

2017-03-01

Rationale and objectives: Observer performance has been widely studied through examining the characteristics of individuals. Applying a systems perspective, while understanding of the system's output, requires a study of the interactions between observers. This research explains a mixed methods approach to applying a social network analysis (SNA), together with a more traditional approach of examining personal/ individual characteristics in understanding observer performance in mammography. Materials and Methods: Using social networks theories and measures in order to understand observer performance, we designed a social networks survey instrument for collecting personal and network data about observers involved in mammography performance studies. We present the results of a study by our group where 31 Australian breast radiologists originally reviewed 60 mammographic cases (comprising of 20 abnormal and 40 normal cases) and then completed an online questionnaire about their social networks and personal characteristics. A jackknife free response operating characteristic (JAFROC) method was used to measure performance of radiologists. JAFROC was tested against various personal and network measures to verify the theoretical model. Results: The results from this study suggest a strong association between social networks and observer performance for Australian radiologists. Network factors accounted for 48% of variance in observer performance, in comparison to 15.5% for the personal characteristics for this study group. Conclusion: This study suggest a strong new direction for research into improving observer performance. Future studies in observer performance should consider social networks' influence as part of their research paradigm, with equal or greater vigour than traditional constructs of personal characteristics.

Hypersonic research engine project. Phase 2: Preliminary report on the performance of the HRE/AIM at Mach 6

NASA Technical Reports Server (NTRS)

Sun, Y. H.; Sainio, W. C.

1975-01-01

Test results of the Aerothermodynamic Integration Model are presented. A program was initiated to develop a hydrogen-fueled research-oriented scramjet for operation between Mach 3 and 8. The primary objectives were to investigate the internal aerothermodynamic characteristics of the engine, to provide realistic design parameters for future hypersonic engine development as well as to evaluate the ground test facility and testing techniques. The engine was tested at the NASA hypersonic tunnel facility with synthetic air at Mach 5, 6, and 7. The hydrogen fuel was heated up to 1500 R prior to injection to simulate a regeneratively cooled system. The engine and component performance at Mach 6 is reported. Inlet performance compared very well both with theory and with subscale model tests. Combustor efficiencies up to 95 percent were attained at an equivalence ratio of unity. Nozzle performance was lower than expected. The overall engine performance was computed using two different methods. The performance was also compared with test data from other sources.

An Evaluation of Sharp Cut Cyclones for Sampling Diesel Particulate Matter Aerosol in the Presence of Respirable Dust

PubMed Central

Cauda, Emanuele; Sheehan, Maura; Gussman, Robert; Kenny, Lee; Volkwein, Jon

2015-01-01

Two prototype cyclones were the subjects of a comparative research campaign with a diesel particulate matter sampler (DPMS) that consists of a respirable cyclone combined with a downstream impactor. The DPMS is currently used in mining environments to separate dust from the diesel particulate matter and to avoid interferences in the analysis of integrated samples and direct-reading monitoring in occupational environments. The sampling characteristics of all three devices were compared using ammonium fluorescein, diesel, and coal dust aerosols. With solid spherical test aerosols at low particle loadings, the aerodynamic size-selection characteristics of all three devices were found to be similar, with 50% penetration efficiencies (d50) close to the design value of 0.8 µm, as required by the US Mine Safety and Health Administration for monitoring occupational exposure to diesel particulate matter in US mining operations. The prototype cyclones were shown to have ‘sharp cut’ size-selection characteristics that equaled or exceeded the sharpness of the DPMS. The penetration of diesel aerosols was optimal for all three samplers, while the results of the tests with coal dust induced the exclusion of one of the prototypes from subsequent testing. The sampling characteristics of the remaining prototype sharp cut cyclone (SCC) and the DPMS were tested with different loading of coal dust. While the characteristics of the SCC remained constant, the deposited respirable coal dust particles altered the size-selection performance of the currently used sampler. This study demonstrates that the SCC performed better overall than the DPMS. PMID:25060240

Hubble Space Telescope NiH2 six battery test

NASA Technical Reports Server (NTRS)

Whitt, Thomas H.; Lanier, J. Roy

1991-01-01

The primary objectives of the test are: (1) to get a better understanding of the operating characteristics of the NiH2 batteries in the Hubble Space Telescope (HST) Electric Power Subsystem (EPS) by simulating every aspect of the expected operating environment; (2) to determine the optimum charge level and charge scheme for the NiH2 batteries in the HST EPS; (3) to predict the performance of the actual HST EPS; (4) to observe the aging characteristics of the batteries; and (5) to test different EPS anomalies before experiencing the anomalies on the actual HST.

Aerodynamic Characteristics, Database Development and Flight Simulation of the X-34 Vehicle

NASA Technical Reports Server (NTRS)

Pamadi, Bandu N.; Brauckmann, Gregory J.; Ruth, Michael J.; Fuhrmann, Henri D.

2000-01-01

An overview of the aerodynamic characteristics, development of the preflight aerodynamic database and flight simulation of the NASA/Orbital X-34 vehicle is presented in this paper. To develop the aerodynamic database, wind tunnel tests from subsonic to hypersonic Mach numbers including ground effect tests at low subsonic speeds were conducted in various facilities at the NASA Langley Research Center. Where wind tunnel test data was not available, engineering level analysis is used to fill the gaps in the database. Using this aerodynamic data, simulations have been performed for typical design reference missions of the X-34 vehicle.

Performance evaluation of candidate space suit elements for the next generation orbital EMU

NASA Technical Reports Server (NTRS)

West, Philip R.; Trausch, Stephanie V.

1992-01-01

The AX-5 all metallic, multibearing technologies developed at the Ames Research Center and the Mk III fabric and metallic technologies developed at the Johnson Space Center were evaluated using the current Space Shuttle space suit technologies as a baseline. Manned evaluations were performed in the Weightless Environment Training Facility and KC-135 zero-gravity aircraft. Joint torque, range, cycle life, and environmental protection characteristics were analyzed during unmanned tests. Both numerical results and test subject comments on performance are presented.

ENVIRONMENTAL TECHNOLOGY VERIFICATION COATINGS AND COATING EQUIPMENT PROGRAM (ETV CCEP), FINAL TECHNOLOGY APPLICATIONS GROUP TAGNITE--TESTING AND QUALITY ASSURANCE PLAN (T/QAP)

EPA Science Inventory

The overall objective of the Environmental Testing and Verification Coatings and Coating Equipment Program is to verify pollution prevention and performance characteristics of coating technologies and make the results of the testing available to prospective coating technology use...

Effects of Selected Object Characteristics on Object Permanence Test Performance.

ERIC Educational Resources Information Center

Lingle, Kathleen M.; Lingle, John H.

A study was conducted to investigate the degree to which both object familiarity and motivational factors influence infants' search behavior in an object permanence test. Infants' search behavior for an unfamiliar test object was compared with search behavior for (a) an experientially familiar object that each infant had played with daily for a…

Predicting Stereotype Threat, Test Anxiety, and Cognitive Ability Test Performance: An Examination of Three Models

ERIC Educational Resources Information Center

Sawyer, Jr., Thomas P.; Hollis-Sawyer, Lisa A.

2005-01-01

As the classroom and workplace, among other contexts, become more diverse in their population characteristics, the need to be aware of specific factors impacting testing outcome issues correspondingly increases. The focus in this study, among other purposes, was to identify possible interactions between examinee's individual-difference…

Free-Spinning Tunnel Tests of a 1/24-Scale Model of the Grumman XTB3F-1 Airplane, TED No. NACA DE304

NASA Technical Reports Server (NTRS)

Berman, Theodore

1947-01-01

In accordance with a request of the Bureau of Aeronautics, Navy Department, tests were performed in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 1/24 scale model of the Grumman XTB3F-1 airplane. The airplane is a two-place, midwing torpedo bomber equipped with a tractor propeller and an auxiliary jet engine. The effect of control setting and movement on the erect and inverted spin and recovery characteristics of the model were determined for the normal loading. Brief tests with mass extended slightly along the fuselage were also made, however, in order to determine the effect of such a mass variation on elevator effectiveness. Tests were performed to determine the size of emergency spin-recovery tail and wing-tip parachutes required for satisfactory recovery by parachute action alone. The investigation also included emergency pilot-escape tests and tests to determine the rudder pedal and elevator stick forces necessary to move the rudder and elevator for recovery.

Performance Test of Laser Velocimeter System for the Langley 16-foot Transonic Tunnel

NASA Technical Reports Server (NTRS)

Meyers, J. F.; Hunter, W. W., Jr.; Reubush, D. E.; Nichols, C. E., Jr.; Hepner, T. E.; Lee, J. W.

1985-01-01

An investigation in the Langley 16-Foot Transonic Tunnel has been conducted in which a laser velocimeter was used to measure free-stream velocities from Mach 0.1 to 1.0 and the flow velocities along the stagnating streamline of a hemisphere-cylinder model at Mach 0.8 and 1.0. The flow velocity was also measured at Mach 1.0 along the line 0.533 model diameters below the model. These tests determined the performance characteristics of the dedicated two-component laser velocimeter at flow velocities up to Mach 1.0 and the effects of the wind tunnel environment on the particle-generating system and on the resulting size of the generated particles. To determine these characteristics, the measured particle velocities along the stagnating streamline at the two Mach numbers were compared with the theoretically predicted gas and particle velocities calculated using a transonic potential flow method. Through this comparison the mean detectable particle size (2.1 micron) along with the standard deviation of the detectable particles (0.76 micron) was determined; thus the performance characteristics of the laser velocimeter were established.

An interim report on the MCAT Essay Pilot Project.

PubMed

Koenig, J A; Mitchell, K J

1988-01-01

Results from four pilot administrations of the Medical College Admission Test essay question are reported. Analyses focused on (a) the performance characteristics of sample groups differentiated by gender, size of hometown, race/ethnicity, and dominant language; (b) the relationships between essay scores and academic/demographic characteristics; and (c) the reliability of one 45-minute versus two 30-minute essays. No differences were found for examinees grouped by gender and size of home community. Mean differences among the racial/ethnic groups were explained largely by reading level differences. Differences in essay performance by language group were large and unexplained by reading level differences. No relationship was found between the essay score and the academic/demographic characteristics. Reliability estimates for two 30-minute essays were higher than for one 45-minute essay; however, the 30-minute period yielded writing of poorer quality. Test-retest reliabilities for the 45-minute topics will remain the focus of future studies as will performance by examinees for whom English is a second language. The impact of the essay on the selection process will also be assessed.

Performance characteristics of NuVal and the Overall Nutritional Quality Index (ONQI).

PubMed

Katz, David L; Njike, Valentine Y; Rhee, Lauren Q; Reingold, Arthur; Ayoob, Keith T

2010-04-01

Improving diets has considerable potential to improve health, but progress in this area has been limited, and advice to increase fruit and vegetable intake has largely gone unheeded. Our objective was to test the performance characteristics of the Overall Nutritional Quality Index (ONQI), a tool designed to help improve dietary patterns one well-informed choice at a time. The ONQI was developed by a multidisciplinary group of nutrition and public health scientists independent of food industry interests and is the basis for the NuVal Nutritional Guidance System. Dietary guidelines, existing nutritional scoring systems, and other pertinent scientific literature were reviewed. An algorithm incorporating >30 entries that represent both micro- and macronutrient properties of foods, as well as weighting coefficients representing epidemiologic associations between nutrients and health outcomes, was developed and subjected to consumer research and testing of performance characteristics. ONQI and expert panel rankings correlated highly (R = 0.92, P < 0.001). In consumer testing, approximately 80% of >800 study participants indicated that the ONQI would influence their purchase intent. ONQI scoring distinguished the more-healthful DASH (Dietary Approaches to Stop Hypertension) diet (mean score: 46) from the typical American diet according to the National Health and Nutrition Examination Survey (NHANES) 2003-2006 (mean score: 26.5; P < 0.01). In linear regression analysis of the NHANES 2003-2006 populations (n = 15,900), the NuVal system was significantly associated with the Healthy Eating Index 2005 (P < 0.0001). Recently generated data from ongoing studies indicate favorable effects on purchase patterns and significant correlation with health outcomes in large cohorts of men and women followed for decades. NuVal offers universally applicable nutrition guidance that is independent of food industry interests and is supported by consumer research and scientific evaluation of its performance characteristics.

Fitness testing of tennis players: How valuable is it?

PubMed Central

Fernandez-Fernandez, Jaime; Ulbricht, Alexander; Ferrauti, Alexander

2014-01-01

In tennis, sport-specific technical skills are predominant factors, although a complex profile of physical performance factors is also required. The fitness test batteries assist in examining tennis players’ capabilities for performance at different levels in the laboratory as well as in the field, in the junior or elite level. While laboratory tests can be, and are, used to evaluate basic performance characteristics of athletes in most individual sports, in a more specific approach, field-based methods are better suited to the demands of complex intermittent sports like tennis. A regular test battery performed at different periods of the year allows to obtain an individual's performance profile, as well as the ability to prescribe individual training interventions. Thus, the aim of the present review was to describe and evaluate the different physical tests recommended and used by practitioners, sports scientists and institutions (national tennis federations). PMID:24668375

Effect of wing-tip dihedral on the longitudinal and lateral aerodynamic characteristics of a supersonic cruise configuration at subsonic speeds

NASA Technical Reports Server (NTRS)

Washburn, K. E.; Gloss, B. B.

1976-01-01

Force and moment data studies were conducted to determine the effect of wing-tip dihedral on the longitudinal and lateral aerodynamic characteristics of a supersonic cruise fighter configuration. Oil flow studies were also performed to investigate the model surface flow. Three models were tested: a flat (0 deg dihedral) wing tip, a dihedral, and an anhedral wing tip. The tests were conducted at the NASA Langley high-speed 7- by 10-foot wind tunnel.

A Generalized Simulation Model for a Typical Medical Treatment Facility Obstetrical Unit

DTIC Science & Technology

1993-03-01

not surprising. The medical center has a variety of specialized departments and clinics, each with unique characteristics . Studies performed for these...DRG relates a set of patient’s demographic, dia nostic, and therapeutic characteristics to the hospital’s resources they consume so!that each DRG is... epatient waiting dumanoa tbent wait Patient entle L&D Wxdl wait U (rood 0 . (Dewviy) v ’ Figure 3.5. Inpatient Testing Flowchart 3-9 4- 2 Outpatient testing

Improved, low cost inorganic-organic separators for rechargeable silver-zinc batteries

NASA Technical Reports Server (NTRS)

Sheibley, D. W.

1979-01-01

Several flexible, low-cost inorganic-organic separators with performance characteristics and cycle life equal to, or better than, the Lewis Research Center Astropower separator were developed. These new separators can be made on continuous-production equipment at about one-fourth the cost of the Astropower separator produced the same way. In test cells, these new separators demonstrate cycle life improvement, acceptable operating characteristics, and uniform current density. The various separator formulas, test cell construction, and data analysis are described.

Performance Testing of Yardney MCMB-LiNiCoAlO2 Lithium-ion Cells Possessing Electrolytes with Improved Safety Characteristics

NASA Technical Reports Server (NTRS)

Smart, Marshall C.; Whitcanack, Larry D.; Krause, Frederick C.; Hwang, Constanza; Bugga, Ratnakumar V.; Santee, Stuart; Puglia, Frank J.; Gitzendanner, Rob

2012-01-01

Many future NASA missions aimed at exploring the Moon and Mars require high specific energy rechargeable batteries that possess enhanced safety characteristics. There is also a strong desire to develop Li-ion batteries with improved safety characteristics for terrestrial applications, most notably for HEV and PHEV automotive applications. In previous work focused upon evaluating various potential flame retardant additives1, triphenyl phosphate (TPP)2 was observed to have the most desirable attributes, including good life characteristics and resilience to high voltage operation. We have employed a number of approaches in the design of promising TPP-based electrolytes with improved safety, including: (a) varying the flame retardant additive (FRA) content (from 5 to 15%), (b) the use of fluorinated co-solvents, (c) the use of additives to improve compatibility, and (c) the use of ester co-solvents to decrease the viscosity and increase the conductivity. In recent work, we have demonstrated a number of these electrolyte formulations to be compatible with a number of chemistries, including: MCMB carbon-LiNi0.8Co0.2O2, graphite-LiNi0.8Co0.15Al0.05O2, Li-Li(Li0.17Ni 0.25 Mn 0.58 )O2, Li-LiNiCoMnO2 and graphite- LiNiCoMnO2.3,4 In the current study, we have demonstrated the performance of a number of TPP-containing electrolytes in 7 Ah prototype MCMB-LiNiCoO2 cells. We will describe the results of a number of performance tests, including: a) 100% DOD cycle life testing at various temperatures, b) discharge rate characterization as a function of temperature, c) charge rate characterization as a function of temperature, and d) impedance as a function of temperature. In addition to displaying good life characteristics, being comparable to baseline chemistries, a number of cells were observed to provide good performance over a wide temperature range.

Job control and coworker support improve employee job performance.

PubMed

Nagami, Makiko; Tsutsumi, Akizumi; Tsuchiya, Masao; Morimoto, Kanehisa

2010-01-01

We examined the prospective association of psychosocial job characteristics with employee job performance among 777 full-time employees at a manufacturing company in Japan, using data from a one-year follow-up survey. Psychosocial job characteristics were measured by the Job Content Questionnaire in 2008; job performance was evaluated using the item from the World Mental Health Survey Instrument in 2008 and 2009. The association between psychosocial job characteristics and job performance was tested using multiple regression analysis, controlling for demographic variables, work status, average working hours per day, job type and job performance in 2008. Job control and coworker support in 2008 were positively related to job performance in 2009. Stratified analyses revealed that job control for staff and coworker support for managers were positively related to job performance in 2009. These associations were prominent among men; however, supervisor support in 2008 was negatively related to job performance in 2009 among men. Job demand was not significantly related to job performance. Our findings suggest that it is worthwhile to enhance employees' job control and provide a mutually supportive environment to ensure positive employee job performance.

Performing a Large-Scale Modal Test on the B2 Stand Crane at NASA's Stennis Space Center

NASA Technical Reports Server (NTRS)

Stasiunas, Eric C.; Parks, Russel A.; Sontag, Brendan D.

2018-01-01

A modal test of NASA's Space Launch System (SLS) Core Stage is scheduled to occur at the Stennis Space Center B2 test stand. A derrick crane with a 150-ft long boom, located at the top of the stand, will be used to suspend the Core Stage in order to achieve defined boundary conditions. During this suspended modal test, it is expected that dynamic coupling will occur between the crane and the Core Stage. Therefore, a separate modal test was performed on the B2 crane itself, in order to evaluate the varying dynamic characteristics and correlate math models of the crane. Performing a modal test on such a massive structure was challenging and required creative test setup and procedures, including implementing both AC and DC accelerometers, and performing both classical hammer and operational modal analysis. This paper describes the logistics required to perform this large-scale test, as well as details of the test setup, the modal test methods used, and an overview and application of the results.

Fractured reservoir characterization through injection, falloff, and flowback tests

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

Peng, C.P.; Singh, P.K.; Halvorsen, H.

1992-09-01

This paper presents the development of a multiphase pressure-transient-analysis technique for naturally fractured reservoirs and the analysis of a series of field tests performed to evaluate the water injection potential and the reservoir characteristics of a naturally fractured reservoir. These included step-rate, water-injectivity, pressure-falloff, and flowback tests. Through these tests, a description of the reservoir was obtained.

Patterns of Participation in Year 9 Academic Testing and Factors Predicting Absence on the Day of Test

ERIC Educational Resources Information Center

Wong, Janice W. Y.; O'Donnell, Melissa; Bayliss, Donna; Fletcher, Janet; Glauert, Rebecca

2017-01-01

Policies aiming to improve educational outcomes are typically based on academic testing data. However, such data only reflect the performance of students who completed the tests. It is possible that students who were absent have shared characteristics. The proportion of students absent out of all eligible school students and whether they have…

Separator development and testing of nickel-hydrogen cells

NASA Technical Reports Server (NTRS)

Gonzalez-Sanabria, O. D.; Manzo, M. A.

1984-01-01

The components, design, and operating characteristics of Ni-H2 cells batteries were improved. A separator development program was designed to develop a separator that is resistant to penetration by oxygen and loose active material from then nickel electrode, while retraining the required chemical and thermal stability, reservoir capability, and high ionic conductivity. The performance of the separators in terms of cell operating voltage was to at least match that of state-of-the-art separators while eliminating the separator problems. The separators were submitted to initial screening tests and those which successfully completed the tests were built into Ni-H2 cells for short term testing. The separators with the best performance are tested for long term performance and life.

The National Football League (NFL) combine: does normalized data better predict performance in the NFL draft?

PubMed

Robbins, Daniel W

2010-11-01

The objective of this study was to investigate the predictive ability of National Football League (NFL) combine physical test data to predict draft order over the years 2005-2009. The NFL combine provides a setting in which NFL personnel can evaluate top draft prospects. The predictive ability of combine data in its raw form and when normalized in both a ratio and allometric manner was examined for 17 positions. Data from 8 combine physical performance tests were correlated with draft order to determine the direction and strength of relationship between the various combine measures and draft order. Players invited to the combine and subsequently drafted in the same year (n = 1,155) were included in the study. The primary finding was that performance in the combine physical test battery, whether normalized or not, has little association with draft success. In terms of predicting draft order from outcomes of the 8 tests making up the combine battery, normalized data provided no advantage over raw data. Of the 8 performance measures investigated, straight sprint time and jumping ability seem to hold the most weight with NFL personnel responsible for draft decisions. The NFL should consider revising the combine test battery to reflect the physical characteristics it deems important. It may be that NFL teams are more interested in attributes other than the purely physical traits reflected in the combine test battery. Players with aspirations of entering the NFL may be well advised to develop mental and technical skills in addition to developing the physical characteristics necessary to optimize performance.

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

Rodriguez, J.R.; Ahrens, J.S.; Lowe, D.L.

Throughout the years, Sandia National Laboratories (SNL) has performed various laboratory evaluations of entry control devices, including biometric identity verifiers. The reports which resulted from this testing have been very well received by the physical security community. This same community now requires equally informative field study data. To meet this need we have conducted a field study in an effort to develop the tools and methods which our customers can use to translate laboratory data into operational field performance. The field testing described in this report was based on the Recognition Systems Inc.`s (RSI) model ID3D HandKey biometric verifier. Thismore » device was selected because it is referenced in DOE documents such as the Guide for Implementation of the DOE Standard Badge and is the de facto biometric standard for the DOE. The ID3D HandKey is currently being used at several DOE sites such as Hanford, Rocky Flats, Pantex, Savannah River, and Idaho Nuclear Engineering Laboratory. The ID3D HandKey was laboratory tested at SNL. It performed very well during this test, exhibiting an equal error point of 0.2 percent. The goals of the field test were to identify operational characteristics and design guidelines to help system engineers translate laboratory data into field performance. A secondary goal was to develop tools which could be used by others to evaluate system effectiveness or improve the performance of their systems. Operational characteristics were determined by installing a working system and studying its operation over a five month period. Throughout this test we developed tools which could be used by others to similarly gauge system effectiveness.« less

Design of piezoelectric probe for measurement of longitudinal and shear components of elastic wave

NASA Astrophysics Data System (ADS)

Aoyanagi, Masafumi; Wakatsuki, Naoto; Mizutani, Koichi; Ebihara, Tadashi

2017-07-01

We focus on ultrasonic probes for nondestructive tests and evaluation. Transient characteristics of probes are important for nondestructive tests such as the pulse echo method. We previously reported the principle of measurement using a piezoelectric probe with triaxial sensitivities. In the results, it was calculated that the probe could transmit and receive particle displacement which contains normal and tangential components. It was confirmed that the probe had sensitivities in triaxial directions. However, its performance in terms of frequency and transient characteristics has not been evaluated. The purpose of this study is to design a probe by changing its shape to obtain better performance. The transient characteristics of probes in longitudinal and shear driving were evaluated by the inverse Fourier transformation of frequency responses of longitudinal and shear components, using the two-dimensional finite element method. As a result, the sensitivities at the dips of frequency characteristics increased when using our probe compared with those measured using conventional probes in longitudinal and shear driving. Hence, the performance in terms of the frequency response was improved by more than 3 dB under the conditions in this simulation. Also, the pulse width of impulse response was decreased by half compared with that of probes with conventional shapes.

AGT 1500 Powerpack Improvement Project (M1 TMEPS). Volume 1

DTIC Science & Technology

1991-03-01

culminated in a one week evalUation of the ATR. This was due to funding and schedule constraints. Testing was concentrated on vehicle mobility performance...June 1990 with a one week vehicle demonstration at Milford Proving Grounds. The vehicle performed well but the mobility characteristics, most...all of the nonrecurring, recurring, engineering, data, system test and evaluation, and initial spares costs aplicable to each alternative. TMEPS as a

Performance validity testing in neuropsychology: a clinical guide, critical review, and update on a rapidly evolving literature.

PubMed

Lippa, Sara M

2018-04-01

Over the past two decades, there has been much research on measures of response bias and myriad measures have been validated in a variety of clinical and research samples. This critical review aims to guide clinicians through the use of performance validity tests (PVTs) from test selection and administration through test interpretation and feedback. Recommended cutoffs and relevant test operating characteristics are presented. Other important issues to consider during test selection, administration, interpretation, and feedback are discussed including order effects, coaching, impact on test data, and methods to combine measures and improve predictive power. When interpreting performance validity measures, neuropsychologists must use particular caution in cases of dementia, low intelligence, English as a second language/minority cultures, or low education. PVTs provide valuable information regarding response bias and, under the right circumstances, can provide excellent evidence of response bias. Only after consideration of the entire clinical picture, including validity test performance, can concrete determinations regarding the validity of test data be made.

Survey Definitions of Gout for Epidemiologic Studies: Comparison With Crystal Identification as the Gold Standard.

PubMed

Dalbeth, Nicola; Schumacher, H Ralph; Fransen, Jaap; Neogi, Tuhina; Jansen, Tim L; Brown, Melanie; Louthrenoo, Worawit; Vazquez-Mellado, Janitzia; Eliseev, Maxim; McCarthy, Geraldine; Stamp, Lisa K; Perez-Ruiz, Fernando; Sivera, Francisca; Ea, Hang-Korng; Gerritsen, Martijn; Scire, Carlo A; Cavagna, Lorenzo; Lin, Chingtsai; Chou, Yin-Yi; Tausche, Anne-Kathrin; da Rocha Castelar-Pinheiro, Geraldo; Janssen, Matthijs; Chen, Jiunn-Horng; Cimmino, Marco A; Uhlig, Till; Taylor, William J

2016-12-01

To identify the best-performing survey definition of gout from items commonly available in epidemiologic studies. Survey definitions of gout were identified from 34 epidemiologic studies contributing to the Global Urate Genetics Consortium (GUGC) genome-wide association study. Data from the Study for Updated Gout Classification Criteria (SUGAR) were randomly divided into development and test data sets. A data-driven case definition was formed using logistic regression in the development data set. This definition, along with definitions used in GUGC studies and the 2015 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) gout classification criteria were applied to the test data set, using monosodium urate crystal identification as the gold standard. For all tested GUGC definitions, the simple definition of "self-report of gout or urate-lowering therapy use" had the best test performance characteristics (sensitivity 82%, specificity 72%). The simple definition had similar performance to a SUGAR data-driven case definition with 5 weighted items: self-report, self-report of doctor diagnosis, colchicine use, urate-lowering therapy use, and hyperuricemia (sensitivity 87%, specificity 70%). Both of these definitions performed better than the 1977 American Rheumatism Association survey criteria (sensitivity 82%, specificity 67%). Of all tested definitions, the 2015 ACR/EULAR criteria had the best performance (sensitivity 92%, specificity 89%). A simple definition of "self-report of gout or urate-lowering therapy use" has the best test performance characteristics of existing definitions that use routinely available data. A more complex combination of features is more sensitive, but still lacks good specificity. If a more accurate case definition is required for a particular study, the 2015 ACR/EULAR gout classification criteria should be considered. © 2016, American College of Rheumatology.

The development and testing of a skin tear risk assessment tool.

PubMed

Newall, Nelly; Lewin, Gill F; Bulsara, Max K; Carville, Keryln J; Leslie, Gavin D; Roberts, Pam A

2017-02-01

The aim of the present study is to develop a reliable and valid skin tear risk assessment tool. The six characteristics identified in a previous case control study as constituting the best risk model for skin tear development were used to construct a risk assessment tool. The ability of the tool to predict skin tear development was then tested in a prospective study. Between August 2012 and September 2013, 1466 tertiary hospital patients were assessed at admission and followed up for 10 days to see if they developed a skin tear. The predictive validity of the tool was assessed using receiver operating characteristic (ROC) analysis. When the tool was found not to have performed as well as hoped, secondary analyses were performed to determine whether a potentially better performing risk model could be identified. The tool was found to have high sensitivity but low specificity and therefore have inadequate predictive validity. Secondary analysis of the combined data from this and the previous case control study identified an alternative better performing risk model. The tool developed and tested in this study was found to have inadequate predictive validity. The predictive validity of an alternative, more parsimonious model now needs to be tested. © 2015 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Development of monofilar rotor hub vibration absorber

NASA Technical Reports Server (NTRS)

Duh, J.; Miao, W.

1983-01-01

A design and ground test program was conducted to study the performance of the monofilar absorber for vibration reduction on a four-bladed helicopter. A monofilar is a centrifugal tuned two degree-of-freedom rotor hub absorber that provides force attenuation at two frequencies using the same dynamic mass. Linear and non-linear analyses of the coupled monofilar/airframe system were developed to study tuning and attenuation characteristics. Based on the analysis, a design was fabricated and impact bench tests verified the calculated non-rotating natural frequencies and mode shapes. Performance characteristics were measured using a rotating absorber test facility. These tests showed significant attenuation of fixed-system 4P hub motions due to 3P inplane rotating-system hub forces. In addition, detuning effects of the 3P monofilar modal response were small due to the nonlinearities and tuning pin slippage. However, attenuation of 4P hub motions due to 5P inplane hub forces was poor. The performance of the 5P monofilar modal response was degraded by torsional motion of the dynamic mass relative to the support arm which resulted in binding of the dynamic components. Analytical design studies were performed to evaluate this torsional motion problem. An alternative design is proposed which may alleviate the torsional motion of the dynamic mass.

Performance of lead-rubber and sliding bearings under different axial load and velocity conditions.

DOT National Transportation Integrated Search

2008-05-01

A series of tests on full scale devices for bridge application were completed. Two types of isolators were considered: lead-rubber bearings and sliding bearings. The main performance characteristics of these devices were already acquired through exte...

Fatigue tests of YBCO coated conductors

NASA Astrophysics Data System (ADS)

Bamba, S.; Tanaka, Y.; Ando, T.; Ueda, H.; Ishiyama, A.; Yamada, Y.; Shiohara, Y.

2008-02-01

In this paper, we report the fatigue characteristics of IBAD/PLD YBCO coated conductors. A YBCO coated conductor used in the superconducting coil of a SMES system is repeatedly subjected to mechanical tensile or compressive strain due to the Lorentz force during electrical charging or discharging. The superconducting characteristic of this conductor may deteriorate because of this cyclic strain. Therefore, it is necessary to investigate the effect of cyclic strain on the superconducting characteristics of YBCO coated conductors that have a laminated structure. We developed an experimental apparatus with a U-shaped sample holder in order to apply cyclic strain to the sample tape. This apparatus was used to perform the fatigue tests on YBCO coated conductors in liquid nitrogen in the absence of an external magnetic field. The strain cycles with the maximum strain epsilonmax (zero external strain → epsilonmax → zero external strain) were applied and repeated up to 5000 times, and the Ic measurements were performed at epsilonmax. Therefore, the application of cyclic strain with epsilonmax ranging from 0.3% to 0.5% did not result in any significant deterioration of the superconducting characteristics of the conductor.

Pumped storage system model and experimental investigations on S-induced issues during transients

NASA Astrophysics Data System (ADS)

Zeng, Wei; Yang, Jiandong; Hu, Jinhong

2017-06-01

Because of the important role of pumped storage stations in the peak regulation and frequency control of a power grid, pump turbines must rapidly switch between different operating modes, such as fast startup and load rejection. However, pump turbines go through the unstable S region in these transition processes, threatening the security and stability of the pumped storage station. This issue has mainly been investigated through numerical simulations, while field experiments generally involve high risks and are difficult to perform. Therefore, in this work, the model test method was employed to study S-induced security and stability issues for a pumped storage station in transition processes. First, a pumped storage system model was set up, including the piping system, model units, electrical control systems and measurement system. In this model, two pump turbines with different S-shaped characteristics were installed to determine the influence of S-shaped characteristics on transition processes. The model platform can be applied to simulate any hydraulic transition process that occurs in real power stations, such as load rejection, startup, and grid connection. On the experimental platform, the S-shaped characteristic curves were measured to be the basis of other experiments. Runaway experiments were performed to verify the impact of the S-shaped characteristics on the pump turbine runaway stability. Full load rejection tests were performed to validate the effect of the S-shaped characteristics on the water-hammer pressure. The condition of one pump turbine rejecting its load after another defined as one-after-another (OAA) load rejection was performed to validate the possibility of S-induced extreme draft tube pressure. Load rejection experiments with different guide vane closing schemes were performed to determine a suitable scheme to adapt the S-shaped characteristics. Through these experiments, the threats existing in the station were verified, the appropriate measures were summarized, and an important experimental basis for the safe and stable operation of a pumped storage station was provided.

Acquisition/expulsion system for earth orbital propulsion system study. Volume 3: Cryogenic test

NASA Technical Reports Server (NTRS)

1973-01-01

A ground test program was conducted to verify several of the design methods and techniques that were used in designing cryogenic acquisition/expulsion systems. The testing of a 63.5-cm diameter DSL subscale model was particularly significant. Under these tests, the operational characteristics of the DSL concept were verified using LH2 and LN2. Demonstration of the gas free liquid expulsion characteristics was accomplished by expelling LH2 under -1 g using both GH2 and GHe pressurization. Loading of the acquisition/expulsion device was successfully accomplished using LH2 and LN2. The liquid free vapor venting performance of the model was limited because of the thermal stratification under the -1 g test conditions.

A statistical assessment of differences and equivalences between genetically modified and reference plant varieties

PubMed Central

2011-01-01

Background Safety assessment of genetically modified organisms is currently often performed by comparative evaluation. However, natural variation of plant characteristics between commercial varieties is usually not considered explicitly in the statistical computations underlying the assessment. Results Statistical methods are described for the assessment of the difference between a genetically modified (GM) plant variety and a conventional non-GM counterpart, and for the assessment of the equivalence between the GM variety and a group of reference plant varieties which have a history of safe use. It is proposed to present the results of both difference and equivalence testing for all relevant plant characteristics simultaneously in one or a few graphs, as an aid for further interpretation in safety assessment. A procedure is suggested to derive equivalence limits from the observed results for the reference plant varieties using a specific implementation of the linear mixed model. Three different equivalence tests are defined to classify any result in one of four equivalence classes. The performance of the proposed methods is investigated by a simulation study, and the methods are illustrated on compositional data from a field study on maize grain. Conclusions A clear distinction of practical relevance is shown between difference and equivalence testing. The proposed tests are shown to have appropriate performance characteristics by simulation, and the proposed simultaneous graphical representation of results was found to be helpful for the interpretation of results from a practical field trial data set. PMID:21324199

Minimalist Running Shoes and Injury Risk Among United States Army Soldiers.

PubMed

Grier, Tyson; Canham-Chervak, Michelle; Bushman, Timothy; Anderson, Morgan; North, William; Jones, Bruce H

2016-06-01

Minimalist running shoes (MRS) are lightweight, are extremely flexible, and have little to no cushioning. It has been thought that MRS will enhance running performance and decrease injury risk. To compare physical characteristics, fitness performance, and injury risks associated with soldiers wearing MRS and those wearing traditional running shoes (TRS). Case series; Level of evidence, 4. Participants were men in a United States Army brigade (N = 1332). Physical characteristics and Army Physical Fitness Test data were obtained by survey. Fitness performance testing was administered at the brigade, and the types of footwear worn were identified by visual inspection. Shoe types were categorized into 2 groups: TRS (stability, cushioning, and motion control) and MRS. Injuries from the previous 12 months were obtained from the Defense Medical Surveillance System. A t test was used to determine mean differences between personal characteristics, training, and fitness performance metrics by shoe type. Hazard ratios and 95% CIs were calculated to determine injury risk by shoe type, controlling for other risk factors. A majority of soldiers wore cushioning shoes (57%), followed by stability shoes (24%), MRS (17%), and motion control shoes (2%). Soldiers wearing MRS were slightly younger than those wearing TRS (P < .01); performed more push-ups, sit-ups, and pull-ups (P < .01); and ran faster during the 2-mile run (P = .01). When other risk factors were controlled, there was no difference in injury risk for running shoe type between soldiers wearing MRS compared with TRS. Soldiers who chose to wear MRS were younger and had higher physical performance scores compared with soldiers wearing TRS. When these differences are controlled, use of MRS does not appear to be associated with higher or lower injury risk in this population. © 2016 The Author(s).

Experimental Study of the Seismic Performance of L-Shaped Columns with 500 MPa Steel Bars

PubMed Central

Wang, Tiecheng; Liu, Xiao; Zhao, Hailong

2014-01-01

Based on tests on six L-shaped RC columns with 500 MPa steel bars, the effect of axial compression ratios and stirrup spacing on failure mode, bearing capacity, displacement, and curvature ductility of the specimens is investigated. Test results show that specimens with lower axial load and large stirrup characteristic value (larger than about 0.35) are better at ductility and seismic performance, while specimens under high axial load or with a small stirrup characteristic value (less than about 0.35) are poorer at ductility; L-shaped columns with 500 MPa steel bars show better bearing capacity and ductility in comparison with specimens with HRB400 steel bars. PMID:24967420

16 CFR 1207.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... means members providing structural support to the assembled, installed slide. (5) Casual contact means...) Performance test means a test to measure the functional or structural characteristics of the slide and may... measurements of the slide's response to dynamic and static loads. (20) [Reserved] (21) Pinching hazard means...

Performance Demonstration of Mcmb-LiNiCoO2 Cells Containing Electrolytes Designed for Wide Operating Temperature Range

NASA Technical Reports Server (NTRS)

Smart, M. C.; Ratnakumar, B. V.; Whicanack, L. D.; Smith, K. A.; Santee, S.; Puglia, F. J.; Gitzendanner, R.

2009-01-01

With the intent of improving the performance of Li-ion cells over a wide operating temperature range, we have investigated the use of co-solvents to improve the properties of electrolyte formulations. In the current study, we have focused upon evaluating promising electrolytes which have been incorporated into large capacity (7 Ah) prototype Li-ion cells, fabricated by Yardney Technical Products, Inc. The electrolytes selected for performance evaluation include the use of a number of esters as co-solvents, including methyl propionate (MP), ethyl propionate (EP), ethyl butyrate (EB), propyl butyrate (PB), and 2,2,2-trifluoroethyl butyrate (TFEB). The performance of the prototype cells containing the ester-based electrolytes was compared with an extensive data base generated on cells containing previously developed all carbonate-based electrolytes. A number of performance tests were performed, including determining (i) the discharge rate capacity over a wide range of temperatures, (ii) the charge characteristics, (iii) the cycle life characteristics under various conditions, and (iv) the impedance characteristics.

Effect of Provider Experience on Clinician-Performed Ultrasonography for Hydronephrosis in Patients With Suspected Renal Colic

PubMed Central

Herbst, Meghan K.; Rosenberg, Graeme; Daniels, Brock; Gross, Cary P.; Singh, Dinesh; Molinaro, Annette M.; Luty, Seth; Moore, Christopher L.

2016-01-01

Study objective Hydronephrosis is readily visible on ultrasonography and is a strong predictor of ureteral stones, but ultrasonography is a user-dependent technology and the test characteristics of clinician-performed ultrasonography for hydronephrosis are incompletely characterized, as is the effect of ultrasound fellowship training on predictive accuracy. We seek to determine the test characteristics of ultrasonography for detecting hydronephrosis when performed by clinicians with a wide range of experience under conditions of direct patient care. Methods This was a prospective study of patients presenting to an academic medical center emergency department with suspected renal colic. Before computed tomography (CT) results, an emergency clinician performed bedside ultrasonography, recording the presence and degree of hydronephrosis. CT data were abstracted from the dictated radiology report by an investigator blinded to the bedside ultrasonographic results. Test characteristics of bedside ultrasonography for hydronephrosis were calculated with the CT scan as the reference standard, with test characteristics compared by clinician experience stratified into 4 levels: attending physicians with emergency ultrasound fellowship training, attending physicians without emergency ultrasound fellowship training, ultrasound experienced non–attending physician clinicians (at least 2 weeks of ultrasound training), and ultrasound inexperienced non–attending physician clinicians (physician assistants, nurse practitioners, off-service rotators, and first-year emergency medicine residents with fewer than 2 weeks of ultrasound training). Results There were 670 interpretable bedside ultrasonographic tests performed by 144 unique clinicians, 80.9% of which were performed by clinicians directly involved in the care of the patient. On CT, 47.5% of all subjects had hydronephrosis and 47.0% had a ureteral stone. Among all clinicians, ultrasonography had a sensitivity of 72.6% (95% confidence interval [CI] 65.4% to 78.9%), specificity of 73.3% (95% CI 66.1% to 79.4%), positive likelihood ratio of 2.72 (95% CI 2.25 to 3.27), and negative likelihood ratio of 0.37 (95% CI 0.31 to 0.44) for hydronephrosis, using hydronephrosis on CT as the criterion standard. Among attending physicians with fellowship training, ultrasonography had sensitivity of 92.7% (95% CI 83.8% to 96.9%), positive likelihood ratio of 4.97 (95% CI 2.90 to 8.51), and negative likelihood ratio of 0.08 (95% CI 0.03 to 0.23). Conclusion Overall, ultrasonography performed by emergency clinicians was moderately sensitive and specific for detection of hydronephrosis as seen on CT in patients with suspected renal colic. However, presence or absence of hydronephrosis as determined by emergency physicians with fellowship training in ultrasonography yielded more definitive test results. For clinicians without fellowship training, there was no significant difference between groups in the predictive accuracy of the application according to experience level. PMID:24630203

Effect of provider experience on clinician-performed ultrasonography for hydronephrosis in patients with suspected renal colic.

PubMed

Herbst, Meghan K; Rosenberg, Graeme; Daniels, Brock; Gross, Cary P; Singh, Dinesh; Molinaro, Annette M; Luty, Seth; Moore, Christopher L

2014-09-01

Hydronephrosis is readily visible on ultrasonography and is a strong predictor of ureteral stones, but ultrasonography is a user-dependent technology and the test characteristics of clinician-performed ultrasonography for hydronephrosis are incompletely characterized, as is the effect of ultrasound fellowship training on predictive accuracy. We seek to determine the test characteristics of ultrasonography for detecting hydronephrosis when performed by clinicians with a wide range of experience under conditions of direct patient care. This was a prospective study of patients presenting to an academic medical center emergency department with suspected renal colic. Before computed tomography (CT) results, an emergency clinician performed bedside ultrasonography, recording the presence and degree of hydronephrosis. CT data were abstracted from the dictated radiology report by an investigator blinded to the bedside ultrasonographic results. Test characteristics of bedside ultrasonography for hydronephrosis were calculated with the CT scan as the reference standard, with test characteristics compared by clinician experience stratified into 4 levels: attending physicians with emergency ultrasound fellowship training, attending physicians without emergency ultrasound fellowship training, ultrasound experienced non-attending physician clinicians (at least 2 weeks of ultrasound training), and ultrasound inexperienced non-attending physician clinicians (physician assistants, nurse practitioners, off-service rotators, and first-year emergency medicine residents with fewer than 2 weeks of ultrasound training). There were 670 interpretable bedside ultrasonographic tests performed by 144 unique clinicians, 80.9% of which were performed by clinicians directly involved in the care of the patient. On CT, 47.5% of all subjects had hydronephrosis and 47.0% had a ureteral stone. Among all clinicians, ultrasonography had a sensitivity of 72.6% (95% confidence interval [CI] 65.4% to 78.9%), specificity of 73.3% (95% CI 66.1% to 79.4%), positive likelihood ratio of 2.72 (95% CI 2.25 to 3.27), and negative likelihood ratio of 0.37 (95% CI 0.31 to 0.44) for hydronephrosis, using hydronephrosis on CT as the criterion standard. Among attending physicians with fellowship training, ultrasonography had sensitivity of 92.7% (95% CI 83.8% to 96.9%), positive likelihood ratio of 4.97 (95% CI 2.90 to 8.51), and negative likelihood ratio of 0.08 (95% CI 0.03 to 0.23). Overall, ultrasonography performed by emergency clinicians was moderately sensitive and specific for detection of hydronephrosis as seen on CT in patients with suspected renal colic. However, presence or absence of hydronephrosis as determined by emergency physicians with fellowship training in ultrasonography yielded more definitive test results. For clinicians without fellowship training, there was no significant difference between groups in the predictive accuracy of the application according to experience level. Copyright © 2014 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.

Parametric analyses of planned flowing uranium hexafluoride critical experiments

NASA Technical Reports Server (NTRS)

Rodgers, R. J.; Latham, T. S.

1976-01-01

Analytical investigations were conducted to determine preliminary design and operating characteristics of flowing uranium hexafluoride (UF6) gaseous nuclear reactor experiments in which a hybrid core configuration comprised of UF6 gas and a region of solid fuel will be employed. The investigations are part of a planned program to perform a series of experiments of increasing performance, culminating in an approximately 5 MW fissioning uranium plasma experiment. A preliminary design is described for an argon buffer gas confined, UF6 flow loop system for future use in flowing critical experiments. Initial calculations to estimate the operating characteristics of the gaseous fissioning UF6 in a confined flow test at a pressure of 4 atm, indicate temperature increases of approximately 100 and 1000 K in the UF6 may be obtained for total test power levels of 100 kW and 1 MW for test times of 320 and 32 sec, respectively.

Speech-discrimination scores modeled as a binomial variable.

PubMed

Thornton, A R; Raffin, M J

1978-09-01

Many studies have reported variability data for tests of speech discrimination, and the disparate results of these studies have not been given a simple explanation. Arguments over the relative merits of 25- vs 50-word tests have ignored the basic mathematical properties inherent in the use of percentage scores. The present study models performance on clinical tests of speech discrimination as a binomial variable. A binomial model was developed, and some of its characteristics were tested against data from 4120 scores obtained on the CID Auditory Test W-22. A table for determining significant deviations between scores was generated and compared to observed differences in half-list scores for the W-22 tests. Good agreement was found between predicted and observed values. Implications of the binomial characteristics of speech-discrimination scores are discussed.

Health Monitoring System for Composite Structures

NASA Technical Reports Server (NTRS)

Tang, S. S.; Riccardella, P. C.; Andrews, R. J.; Grady, J. E.; Mucciaradi, A. N.

1996-01-01

An automated system was developed to monitor the health status of composites. It uses the vibration characteristics of composites to identify a component's damage condition. The vibration responses are characterized by a set of signal features defined in the time, frequency and spatial domains. The identification of these changes in the vibration characteristics corresponding to different health conditions was performed using pattern recognition principles. This allows efficient data reduction and interpretation of vast amounts of information. Test components were manufactured from isogrid panels to evaluate performance of the monitoring system. The components were damaged by impact to simulate different health conditions. Free vibration response was induced by a tap test on the test components. The monitoring system was trained using these free vibration responses to identify three different health conditions. They are undamaged vs. damaged, damage location and damage zone size. High reliability in identifying the correct component health condition was achieved by the monitoring system.

HYDRA, a new tool for mechanical testing

NASA Technical Reports Server (NTRS)

Brinkmann, P. W.

1994-01-01

The introduction outlines the verification concept for programs of the European Space Agency (ESA). The role of the Agency in coordinating the activities of major European space test centers is summarized. Major test facilities of the environmental test center at ESTEC, the Space Research and Technology Center of ESA, are shown and their specific characteristics are highlighted with special emphasis on the 6-degree-of-freedom (6-DOF) hydraulic shaker. The specified performance characteristics for sine and transient tests are presented. Results of single-axis hardware tests and 6-DOF computer simulations are included. Efforts employed to protect payloads against accidental damage in case of malfunctions of the facility are listed. Finally the operational advantages of the facility, as well as the possible use of the HYDRA control system design for future applications are indicated.

Vertical Descent and Landing Tests of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane in Still Air, TED No. NACA DE 368

NASA Technical Reports Server (NTRS)

Smith, Charlee C., Jr.; Lovell, Powell M., Jr.

1954-01-01

An investigation is being conducted to determine the dynamic stability and control characteristics of a 0.13-scale flying model of Convair XFY-1 vertically rising airplane. This paper presents the results of flight and force tests to determine the stability and control characteristics of the model in vertical descent and landings in still air. The tests indicated that landings, including vertical descent from altitudes representing up to 400 feet for the full-scale airplane and at rates of descent up to 15 or 20 feet per second (full scale), can be performed satisfactorily. Sustained vertical descent in still air probably will be more difficult to perform because of large random trim changes that become greater as the descent velocity is increased. A slight steady head wind or cross wind might be sufficient to eliminate the random trim changes.

Magnetic materials selection for static inverter and converter transformers

NASA Technical Reports Server (NTRS)

Mclyman, C. W. T.

1971-01-01

Different magnetic alloys best suited for high-frequency and high-efficiency applications were comparatively investigated together with an investigation of each alloy's inherent characteristics. One of the characteristics in magnetic materials deterimental in transformer design is the residual flux density, which can be additive on turn-on and cause the transformer to saturate. Investigation of this problem led to the design of a transformer with a very low residual flux. Tests were performed to determine the dc and ac magnetic properties at 2400 Hz using square-wave excitation. These tests were performed on uncut cores, which were then cut for comparison of the gapped and ungapped magnetic properties. The optimum transformer was found to be that with the lowest residual flux and a small amount of air gap in the magnetic material. The data obtained from these tests are described, and the potential uses for the materials are discussed.

Development of the Coastal Zone Color Scanner for NIMBUS 7. Volume 2: Test and performance data, revision A

NASA Technical Reports Server (NTRS)

1979-01-01

The results of the Coastal Zone Color Scanner protoflight tests are examined in detail while some of the test results are evaluated with respect to expected performance. Performance characteristics examined include spectral response, signal to noise ratio as a function of radiance input, radiance response, the modulation transfer function, and the field of view and coregistration. The results of orbital sequence tests are also included. The in orbit performance or return of radiometric data in the six spectral bands is evaluated along with the data processing sequence necessary to derive the final data products. Examples of the raw data are given and the housekeeping or diagnostic data which provides information on the day to day health or status of the instrument are discussed.

Advance prototype silver ion water bactericide system

NASA Technical Reports Server (NTRS)

Jasionowski, W. J.; Allen, E. T.

1974-01-01

An advance prototype unit was designed and fabricated to treat anticipated fuel cell water. The unit is a single canister that contains a membrane-type prefilter and a silver bromide contacting bed. A seven day baseline simulated mission test was performed; the performance was satisfactory and the effluent water was within all specifications for potability. After random vibrations another seven day simulated mission test was performed, and results indicate that simulated launch vibrations have no effects on the design and performance of the advanced prototype. Bench tests and accelerated breadboard tests were conducted to define the characteristics of an upgraded model of the advance prototype unit which would have 30 days of operating capability. A preliminary design of a silver ion generator for the shuttle orbiter was also prepared.

The noncavitating performance and life of a small vane-type positive displacement pump in liquid hydrogen

NASA Technical Reports Server (NTRS)

Ulbricht, T. E.; Hemminger, J. A.

1986-01-01

The low flow rate and high head rise requirements of hydrogen/oxygen auxiliary propulsion systems make the application of centrifugal pumps difficult. Positive displacement pumps are well-suited for these flow conditions, but little is known about their performance and life characteristics in liquid hydrogen. An experimental and analytical investigation was conducted to determine the performance and life characteristics of a vane-type, positive displacement pump. In the experimental part of this effort, mass flow rate and shaft torque were determined as functions of shaft speed and pump pressure rise. Since liquid hydrogen offers little lubrication in a rubbing situation, pump life is an issue. During the life test, the pump was operated intermittently for 10 hr at the steady-state point of 0.074 lbm/sec (0.03 kg/sec) flow rate, 3000 psid (2.07 MPa) pressure rise, and 8000 rpm (838 rad/sec) shaft speed. Pump performance was monitored during the life test series and the results indicated no loss in performance. Material loss from the vanes was recorded and wear of the other components was documented. In the analytical part of this effort, a comprehensive pump performance analysis computer code, developed in-house, was used to predict pump performance. The results of the experimental investigation are presented and compared with the results of the analysis. Results of the life test are also presented.

Heat Rejection Systems Utilizing Composites and Heat Pipes: Design and Performance Testing

NASA Technical Reports Server (NTRS)

Jaworske, Donald A.; Beach, Duane E.; Sanzi, James L.

2007-01-01

Polymer matrix composites offer the promise of reducing the mass and increasing the performance of future heat rejection systems. With lifetimes for heat rejection systems reaching a decade or more in a micrometeoroid environment, use of multiple heat pipes for fault tolerant design is compelling. The combination of polymer matrix composites and heat pipes is of particular interest for heat rejection systems operating on the lunar surface. A technology development effort is under way to study the performance of two radiator demonstration units manufactured with different polymer matrix composite face sheet resin and bonding adhesives, along with different titanium-water heat pipe designs. Common to the two radiator demonstration units is the use of high thermal conductivity fibers in the face sheets and high thermal conductivity graphite saddles within a light weight aluminum honeycomb core. Testing of the radiator demonstration units included thermal vacuum exposure and thermal vacuum exposure with a simulated heat pipe failure. Steady state performance data were obtained at different operating temperatures to identify heat transfer and thermal resistance characteristics. Heat pipe failure was simulated by removing the input power from an individual heat pipe in order to identify the diminished performance characteristics of the entire panel after a micrometeoroid strike. Freeze-thaw performance was also of interest. This paper presents a summary of the two radiator demonstration units manufactured to support this technology development effort along with the thermal performance characteristics obtained to date. Future work will also be discussed.

Development of superconductor magnetic suspension and balance prototype facility for studying the feasibility of applying this technique to large scale aerodynamic testing

NASA Technical Reports Server (NTRS)

Zapata, R. N.; Humphris, R. R.; Henderson, K. C.

1975-01-01

The unique design and operational characteristics of a prototype magnetic suspension and balance facility which utilizes superconductor technology are described and discussed from the point of view of scalability to large sizes. The successful experimental demonstration of the feasibility of this new magnetic suspension concept of the University of Virginia, together with the success of the cryogenic wind-tunnel concept developed at Langley Research Center, appear to have finally opened the way to clean-tunnel, high-Re aerodynamic testing. Results of calculations corresponding to a two-step design extrapolation from the observed performance of the prototype magnetic suspension system to a system compatible with the projected cryogenic transonic research tunnel are presented to give an order-of-magnitude estimate of expected performance characteristics. Research areas where progress should lead to improved design and performance of large facilities are discussed.

High mobility high efficiency organic films based on pure organic materials

DOEpatents

Salzman, Rhonda F [Ann Arbor, MI; Forrest, Stephen R [Ann Arbor, MI

2009-01-27

A method of purifying small molecule organic material, performed as a series of operations beginning with a first sample of the organic small molecule material. The first step is to purify the organic small molecule material by thermal gradient sublimation. The second step is to test the purity of at least one sample from the purified organic small molecule material by spectroscopy. The third step is to repeat the first through third steps on the purified small molecule material if the spectroscopic testing reveals any peaks exceeding a threshold percentage of a magnitude of a characteristic peak of a target organic small molecule. The steps are performed at least twice. The threshold percentage is at most 10%. Preferably the threshold percentage is 5% and more preferably 2%. The threshold percentage may be selected based on the spectra of past samples that achieved target performance characteristics in finished devices.

Low speed and angle of attack effects on sonic and near-sonic inlets

NASA Technical Reports Server (NTRS)

Hickcox, T. E.; Lawrence, R. L.; Syberg, J.; Wiley, D. R.

1975-01-01

Tests of the Quiet, Clean Short-Haul Experimental Engine (QCSEE) were conducted to determine the effects of forward velocity and angle of attack on sonic and near-sonic inlet aerodynamic performance penalties and acoustic suppression characteristics. The tests demonstrate that translating centerbody and radial vane sonic inlets, and QCSEE high throat Mach number inlets, can be designed to operate effectively at forward speed and moderate angle of attack with good performance and noise suppression capability. The test equipment and procedures used in conducting the evaluation are described. Results of the tests are presented in tabular form.

SNAP-8 refractory boiler development program

NASA Technical Reports Server (NTRS)

Fuller, R. A.

1974-01-01

Performance and endurance tests of the SNAP-8, SN-1 refractory metal boiler are described. The tests were successful and indicated that the boiler heat transfer area could be reduced significantly primarily because of the wetting characteristics of mercury on tantalum in a contaminant-free environment. A continuous endurance test of more than 10,000 hours was conducted without noticeable change in the thermal performance of the boiler. A conclusion of the metallographic examination of the boiler following the endurance test was that expected boiler life would be of the order of 40,000 hours at observed corrosion rates.

Photovoltaic test and demonstration project. [residential energy program

NASA Technical Reports Server (NTRS)

Forestieri, A. F.; Brandhorst, H. W., Jr.; Deyo, J. N.

1976-01-01

The considered project consists of three subprojects related to applications, device performance and diagnostics, and endurance testing. The objectives of the applications subproject include the determination of the operating characteristics for a variety of photovoltaic conversion systems. A system test facility is being constructed in this connection and a prototype residence experiment is to be conducted. Market demand for solar cells is to be stimulated by demonstrating suitability of solar cells for specific near-term applications. Activities conducted in connection with device performance studies and diagnostics are also discussed along with developments in the area of endurance testing.

ARC-1964-AC-32745

NASA Image and Video Library

1964-09-19

XV-5A airplane installed in 40x80ft Subsonic Wind Tunnel at NASA Ames Research Center with Tom Mills. The propulsive lift system was tested to determine power-on performance characteristics in preparation for flight tests. Used in Memoiors of an Aeronautical Engineer, Flight Tests at Ames Research Center 1940-1970 NASA-SP-2002-4526 (Seth B. Anderson)

SMS/GOES cell and battery data analysis report

NASA Technical Reports Server (NTRS)

Armantrout, J. D.

1977-01-01

The nickel-cadmium battery design developed for the Synchronous Meteorological Satellite (SMS) and Geostationary Operational Environmental Satellite (GOES) provided background and guidelines for future development, manufacture, and application of spacecraft batteries. SMS/GOES battery design, development, qualification testing, acceptance testing, and life testing/mission performance characteristics were evaluated for correlation with battery cell manufacturing process variables.

Are RA patients from a non-endemic HCV population screened for HCV? A cross-sectional analysis of three different settings.

PubMed

Skinner-Taylor, Cassandra Michelle; Erhard-Ramírez, Alejandro; Garza-Elizondo, Mario Alberto; Esquivel-Valerio, Jorge Antonio; Abud-Mendoza, Carlos; Martínez-Martínez, Marco Ulises; Vega-Morales, David; Arana-Guajardo, Ana

In Mexico, other risk factors are associated with hepatitis C virus (HCV): prior heroin users, living alone, widower, and northern region residence. Rheumatoid arthritis (RA) patients are considered immunosuppressed and HCV testing is recommended before treatment. The aim of the study was to describe the characteristics of HCV testing in RA patients in three different medical care settings in a non-endemic area. A retrospective observational study was performed using medical records from 960 RA patients describing the indications for HCV testing. The test was performed in 28.6% and the HCV overall frequency was 0.36%. Population characteristics were not associated with an increased risk of HCV infection; therefore, anti-HCV positivity was low. The main reason for testing was before starting biological agents. Due to the low pre-test probability, testing for HCV infection should be personalized; i.e., according to disease prevalence in a particular geographical location and the individual risk factors. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Longitudinal Study of a Novel, Performance-based Measure of Everyday Functional Competence

DTIC Science & Technology

2014-04-01

longitudinal characteristics of the UPSA. Over the past year we have enrolled 25 subjects into our protocol. Of these 24 received the six week follow up... characteristics of the UPSA in these populations, including the severity of decline in this measure over time, the relationship of decline to cognitive...changes in order to determine the validity of the UPSA, and its technical psychometric characteristics (e.g., test-retest reliability). We will

Analysis of high vacuum systems using SINDA'85

NASA Technical Reports Server (NTRS)

Spivey, R. A.; Clanton, S. E.; Moore, J. D.

1993-01-01

The theory, algorithms, and test data correlation analysis of a math model developed to predict performance of the Space Station Freedom Vacuum Exhaust System are presented. The theory used to predict the flow characteristics of viscous, transition, and molecular flow is presented in detail. Development of user subroutines which predict the flow characteristics in conjunction with the SINDA'85/FLUINT analysis software are discussed. The resistance-capacitance network approach with application to vacuum system analysis is demonstrated and results from the model are correlated with test data. The model was developed to predict the performance of the Space Station Freedom Vacuum Exhaust System. However, the unique use of the user subroutines developed in this model and written into the SINDA'85/FLUINT thermal analysis model provides a powerful tool that can be used to predict the transient performance of vacuum systems and gas flow in tubes of virtually any geometry. This can be accomplished using a resistance-capacitance (R-C) method very similar to the methods used to perform thermal analyses.

A performance-based evaluation of chemically similar (carbonate) tempers from Late Prehistoric (AD 1200-1700) Ohio: Implications for human selection and production of ceramic technology

PubMed Central

Spurlock, Linda B.; Fisch, Michael

2018-01-01

Purpose This study was designed to assess the mechanical properties of two calcium carbonate tempers, limestone and burnt shell. These tempers have been previously compared, in separate studies, to silicate-based grit or sand temper and, relative to the latter, are assumed to possess similar mechanical properties. However, their simultaneous use at the Morrison Village site begs the question: do these two calcium carbonate tempers indeed possess similar mechanical properties? In order to assess their performance characteristics, a side-by-side controlled experimental test was conducted to determine the degree of similarity in providing increased vessel strength and toughness. Methods Standardized ceramic test samples were systematically prepared via a set, explicit protocol. An Instron Series IX universal testing machine configured with a four-point flexural test jig was used to perform a flexural strength test of the test samples. The Instron load and deflection data were used to calculate three values related to mechanical performance: peak load, modulus of rupture, and modulus of elasticity. Results All four comparative tests clearly show substantial differences in peak load, modulus of rupture, and modulus of elasticity. These differences are statistically significant for each performance attribute in every iteration of the experiment and as indicated by Mann-Whitney U Tests. Conclusions These results do not support the hypothesis that limestone and burnt shell offer the same performance characteristics. These results have implications for our understanding of prehistoric human selection of temper and the evolution of ceramic technology. Although both carbonate-based tempers are currently thought to offer the same benefits during the initial phase of pottery production, their contrasting post firing properties would have provided distinct benefits in different contexts. Future assessments of the Morrison Village ceramic assemblage should focus on residue analysis, or other functional indicators, to support or falsify this hypothesis. PMID:29579085

Verification of examination procedures in clinical laboratory for imprecision, trueness and diagnostic accuracy according to ISO 15189:2012: a pragmatic approach.

PubMed

Antonelli, Giorgia; Padoan, Andrea; Aita, Ada; Sciacovelli, Laura; Plebani, Mario

2017-08-28

Background The International Standard ISO 15189 is recognized as a valuable guide in ensuring high quality clinical laboratory services and promoting the harmonization of accreditation programmes in laboratory medicine. Examination procedures must be verified in order to guarantee that their performance characteristics are congruent with the intended scope of the test. The aim of the present study was to propose a practice model for implementing procedures employed for the verification of validated examination procedures already used for at least 2 years in our laboratory, in agreement with the ISO 15189 requirement at the Section 5.5.1.2. Methods In order to identify the operative procedure to be used, approved documents were identified, together with the definition of performance characteristics to be evaluated for the different methods; the examination procedures used in laboratory were analyzed and checked for performance specifications reported by manufacturers. Then, operative flow charts were identified to compare the laboratory performance characteristics with those declared by manufacturers. Results The choice of performance characteristics for verification was based on approved documents used as guidance, and the specific purpose tests undertaken, a consideration being made of: imprecision and trueness for quantitative methods; diagnostic accuracy for qualitative methods; imprecision together with diagnostic accuracy for semi-quantitative methods. Conclusions The described approach, balancing technological possibilities, risks and costs and assuring the compliance of the fundamental component of result accuracy, appears promising as an easily applicable and flexible procedure helping laboratories to comply with the ISO 15189 requirements.

Preclinical testing for aortic endovascular grafts: results of a Food and Drug Administration workshop.

PubMed

Abel, Dorothy B; Beebe, Hugh G; Dedashtian, Mark M; Morton, Michael C; Moynahan, Megan; Smith, Loius J; Weinberg, Steven L

2002-05-01

Since their introduction into clinical trials in the United States, endovascular aortic grafts have shown various types of problems. Although details of design and construction vary between different endovascular grafts and failure modes have had a variety of causes and clinical effects, the inability of preclinical testing to predict these failures remains common to all endovascular grafts. The need to improve preclinical testing in an attempt to reduce clinical device failures resulted in a Food and Drug Administration-sponsored workshop on endovascular graft preclinical testing held in Rockville, Md, from July 31 to August 1, 2001. FORMAT: The workshop was not designed as a consensus conference. Instead, it provided a forum for bringing stakeholders together to define problems and identify areas of agreement and disagreement. The workshop had 34 invited participants who represented device manufacturers, the medical community, the Food and Drug Administration, and testing facilities, and international attendance was more than 120 people. Discussion centered on: 1, defining the physiologic, anatomic, and morphologic characteristics of abdominal aortic aneurysms before and after endovascular graft treatment; 2, identifying the types of failures that have been observed clinically; and 3, determining which characteristics should be considered during preclinical modeling to better predict clinical performance. Attendees agreed to the need to better define and address anatomic characteristics and changes in the aneurysm after endograft treatment to optimize preclinical testing. Much discussion and little agreement occurred on the importance of flow-related forces on graft performance or the need or ability to define and model physiologic compliance during durability testing. The discussion and conclusions are summarized in this paper and are provided in detail at: http://www.fda.gov/cdrh/meetings/073101workshop.html. The workshop raised awareness of significant performance issues and the challenges of modeling the extremely variable and relatively undefined environment of abdominal aortic aneurysms. Through the interactive format of the workshop, participants identified areas of preclinical testing, device design, and aspects of the simulated environment that need further consideration.

Assessment of noise metrics for application to rotorcraft

NASA Astrophysics Data System (ADS)

McMullen, Andrew L.

It is anticipated that the use of rotorcraft passenger vehicles for shorter journeys will increase because their use can reduce the time between boarding and take-off. The characteristics of rotorcraft noise are very different to that of fixed wing aircraft. There can be strong tonal components, fluctuations that can also make the noise sound impulsive, and future rotorcraft may produce proportionally more low frequency noise content. Most metrics that are used today to predict noise impact on communities around airports (e.g., Ldn) are just functions of A-weighted sound pressure level. To build a better noise annoyance model that can be applied to assess impact of future and current rotorcraft, it is important to understand the perceived sound attributes and how they influence annoyance. A series of psychoacoustic tests were designed and performed to further our understanding of how rotorcraft sound characteristics affect annoyance as well as evaluate the applicability of existing noise metrics as predictors of annoyance due to rotorcraft noise. The effect of the method used to reproduce sounds in the psychoacoustics tests was also investigated, and so tests were conducted in the NASA Langley Exterior Effects Room using loudspeaker arrays to simulate flyovers and in a double walled sound booth using earphones for playback. A semantic differential test was performed, and analysis of subject responses showed the presence of several independent perceptual factors relating to: loudness, sharpness, roughness, tonality, and impulsiveness. A simulation method was developed to alter tonal components in existing rotorcraft flyover recordings to change the impulsiveness and tonality of the sounds. Flyover recordings and simulations with varied attributes were used as stimuli in an annoyance test. Results showed that EPNL and SELA performed well as predictors of annoyance, but outliers to generate trends have tonal related characteristics that could be contributing to annoyance. General trends in results were similar for both test environments, though differences were greater for the annoyance tests than the semantic differential tests.

2007 international meeting on Reduced Enrichment for Research and Test Reactors (RERTR). Abstracts and available papers presented at the meeting

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

NONE

2008-07-15

The Meeting papers discuss research and test reactor fuel performance, manufacturing and testing. Some of the main topics are: conversion from HEU to LEU in different reactors and corresponding problems and activities; flux performance and core lifetime analysis with HEU and LEU fuels; physics and safety characteristics; measurement of gamma field parameters in core with LEU fuel; nondestructive analysis of RERTR fuel; thermal hydraulic analysis; fuel interactions; transient analyses and thermal hydraulics for HEU and LEU cores; microstructure research reactor fuels; post irradiation analysis and performance; computer codes and other related problems.

Highway pavement performance test for colored thin anti-skidding layers

NASA Astrophysics Data System (ADS)

Gao, Wei; Cui, Wei; Xu, Ming

2018-03-01

Based on the actual service condition of highway pavement colored thin anti-skidding layers, with materials of color quartz sand and two-component acrylic resin as basis, we designed such tests as the bond strength, shearing strength, tear strength, fatigue performance and aggregate polished value, and included the freeze-thaw cycle and de-icing salt and other factors in the experiment, connecting with the climate characteristics of circumpolar latitude and low altitude in Heilongjiang province. Through the pavement performance test, it is confirmed that the colored thin anti-skidding layers can adapt to cold and humid climate conditions, and its physical mechanical properties are good.

A study on the flow characteristics of a direct drive turbine for energy conversion generation by experiment and CFD

NASA Astrophysics Data System (ADS)

Cho, Y. J.; Zullah, M. A.; Faizal, M.; Choi, Y. D.; Lee, Y. H.

2012-11-01

A variety of technologies has been proposed to capture the energy from waves. Some of the more promising designs are undergoing demonstration testing at commercial scales. Due to the complexity of most offshore wave energy devices and their motion response in different sea states, physical tank tests are common practice for WEC design. Full scale tests are also necessary, but are expensive and only considered once the design has been optimized. Computational Fluid Dynamics (CFD) is now recognized as an important complement to traditional physical testing techniques in offshore engineering. Once properly calibrated and validated to the problem, CFD offers a high density of test data and results in a reasonable timescale to assist with design changes and improvements to the device. The purpose of this study is to investigate the performance of a newly developed direct drive hydro turbine (DDT), which will be built in a caisson for extraction of wave energy. Experiments and CFD analysis are conducted to clarify the turbine performance and internal flow characteristics. The results show that commercial CFD code can be applied successfully to the simulation of the wave motion in the water tank. The performance of the turbine for wave energy converter is studied continuously for a ongoing project.

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

Chiappetta, R.F.

An explosive`s velocity of detonation (VOD), can be used to indicate a number of important characteristics regarding the product`s performance under specific field and test conditions. A number of new characteristic and transient VOD curves have been identified in the field, which can be used to evaluate explosive performance, control ground vibration amplitudes and frequencies, select the correct amount and type of stemming for use at the collar and in stem decks, eliminate explosive desensitization, evaluate primer performance, design air deck based blasts, evaluate contaminated explosives and to overcome post blast noxious fumes. Tests were conducted over a six yearmore » period in single and multi-hole blasts using laboratory and full scale blast environments. Explosives tested ranged from pure Emulsion to Anfo and various grades of Emulsion/Anfo blends. Field test parameters were; borehole diameter (1 1/2--30 inches), hole depths (10--120 feet), primer size (0.5--6.4 pounds) and the blast environment varied from soft, jelly-like tar sands to some of the hardest iron ore formations. Most tests were instrumented with an array of blast monitoring instrumentation systems consisting of continuous velocity of detonation recorders, high-speed 16 mm cameras, laser-surveying instrumentation and seismographs which were placed in the near and far fields.« less

Phase 2 program on ground test of refanned JT8D turbofan engines and nacelles for the 727 airplane. Volume 3: Ground tests

NASA Technical Reports Server (NTRS)

1975-01-01

The NASA Refan Program included full-scale performance and noise ground tests of both a current production (JT8D-15) and a refanned (JT8D-115) engine. A description of the two ground tests including detailed propulsion, noise, and structural test results is presented. The primary objectives of the total test program were comparison of JT8D-15 and JT8D-115 overall propulsion system performance and noise characteristics and determination of incremental component noise levels. Other objectives of the test program included: (1) determination of acoustic treatment effectiveness; (2) measurement of internal sound pressure levels; (3) measurement of inlet and exhaust hardware performance; (4) determination of center-engine surge margin; and (5) evaluation of certain structural characteristics associated with the 727 refan center-engine inlet duct and JT8D refan engine exhaust system. The JT8D-15 and -115 tests were conducted during September 1974 and January to March 1975, respectively. Analyses of the test data indicated that the JT8D-115, as compared to the JT8D-15, demonstrates a 12.5 percent to 13.2 percent reduction in static specific fuel consumption, and a reduction of 6 to 7 PNdB in a weighted average value of static tone corrected perceived noise level. Separated into noise components, a significant reduction was shown for the inlet fan, aft fan, exhaust duct flow, turbine, and jet noises. However, core noise was increased. Photographs of test stands and test equipment are shown.

Stage effects on stalling and recovery of a high-speed 10-stage axial-flow compressor

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

Copenhaver, W.W.

1988-01-01

Results of a high-speed 10-stage axial-flow compressor test involving overall compressor and individual stage performance while stalling and operating in quasi-steady rotating stall are described. Test procedures and data-acquisition methods used to obtain the dynamic stalling and quasi-steady in-stall data are explained. Unstalled and in-stall time-averaged data obtained from the compressor operating at five different shaft speeds and one off-schedule variable vane condition are presented. Effects of compressor speed and variable geometry on overall compressor in-stall pressure rise and hysteresis extent are illustrated through the use of quasi-steady-stage temperature rise and pressure-rise characteristics. Results indicate that individual stage performance duringmore » overall compressor rotating stall operation varies considerably throughout the length of the compressor. The measured high-speed 10-stage test compressor individual stage pressure and temperature characteristics were input into a stage-by-stage dynamic compressor performance model. Comparison of the model results and measured pressures provided the additional validation necessary to demonstrate the model's ability to predict high-speed multistage compressor stalling and in-stall performance.« less

Design, fabrication, testing and delivery of a solar collector

NASA Technical Reports Server (NTRS)

Sims, W. H.; Ballheim, R. W.; Bartley, S. M.; Smith, G. W.

1976-01-01

A two phase program encompassing the redesign and fabrication of a solar collector which is low in cost and aesthetically appealing is described. Phase one work reviewed the current collector design and developed a low-cost design based on specific design/performance/cost requirements. Throughout this phase selected collector component materials were evaluated by testing and by considering cost, installation, maintainability and durability. The resultant collector design was composed of an absorber plate, insulation, frame, cover, desiccant and sealant. In Phase two, three collector prototypes were fabricated and evaluated for both nonthermal and thermal characteristics. Tests included static load tests of covers, burst pressure tests of absorber plates, and tests for optical characteristics of selective absorber plate coatings. The three prototype collectors were shipped to Marshall Space Flight Center for use in their solar heating and cooling test facility.

Design philosophy of the Jet Propulsion Laboratory infrared detector test facility

NASA Technical Reports Server (NTRS)

Burns, R.; Blessinger, M. A.

1983-01-01

To support the development of advanced infrared remote sensing instrumentation using line and area arrays, a test facility has been developed to characterize the detectors. The necessary performance characteristics of the facility were defined by considering current and projected requirements for detector testing. The completed facility provides the desired level of detector testing capability as well as providing ease of human interaction.

40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

Code of Federal Regulations, 2012 CFR

2012-07-01

... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test day...

40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

Code of Federal Regulations, 2013 CFR

2013-07-01

... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test day...

40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

Code of Federal Regulations, 2014 CFR

2014-07-01

... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test day...

Evaluation program for secondary spacecraft cells

NASA Technical Reports Server (NTRS)

Christy, D. E.

1972-01-01

The life cycle test of secondary spacecraft electric cells is discussed. The purpose of the tests is to insure that all cells put into the life cycle test meet the required specifications. The evaluation program gathers statistical information concerning cell performance characteristics and limitations. Weaknesses in cell design which are discovered during the tests are reported to research facilities in order to increase the service life of the cells.

Accelerated life testing effects on CMOS microcircuit characteristics

NASA Technical Reports Server (NTRS)

1977-01-01

Accelerated life tests were performed on CMOS microcircuits to predict their long term reliability. The consistency of the CMOS microcircuit activation energy between the range of 125 C to 200 C and the range 200 C to 250 C was determined. Results indicate CMOS complexity and the amount of moisture detected inside the devices after testing influences time to failure of tested CMOS devices.

AeroValve Experimental Test Data Final Report

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

Noakes, Mark W.

This report documents the collection of experimental test data and presents performance characteristics for the AeroValve brand prototype pneumatic bidirectional solenoid valves tested at the Oak Ridge National Laboratory (ORNL) in July/August 2014 as part of a validation of AeroValve energy efficiency claims. The test stand and control programs were provided by AeroValve. All raw data and processing are included in the report attachments.

Bench-top validation testing of selected immunological and molecular Renibacterium salmoninarum diagnostic assays by comparison with quantitative bacteriological culture

USGS Publications Warehouse

Elliott, D.G.; Applegate, L.J.; Murray, A.L.; Purcell, M.K.; McKibben, C.L.

2013-01-01

No gold standard assay exhibiting error-free classification of results has been identified for detection of Renibacterium salmoninarum, the causative agent of salmonid bacterial kidney disease. Validation of diagnostic assays for R. salmoninarum has been hindered by its unique characteristics and biology, and difficulties in locating suitable populations of reference test animals. Infection status of fish in test populations is often unknown, and it is commonly assumed that the assay yielding the most positive results has the highest diagnostic accuracy, without consideration of misclassification of results. In this research, quantification of R. salmoninarum in samples by bacteriological culture provided a standardized measure of viable bacteria to evaluate analytical performance characteristics (sensitivity, specificity and repeatability) of non-culture assays in three matrices (phosphate-buffered saline, ovarian fluid and kidney tissue). Non-culture assays included polyclonal enzyme-linked immunosorbent assay (ELISA), direct smear fluorescent antibody technique (FAT), membrane-filtration FAT, nested polymerase chain reaction (nested PCR) and three real-time quantitative PCR assays. Injection challenge of specific pathogen-free Chinook salmon, Oncorhynchus tshawytscha (Walbaum), with R. salmoninarum was used to estimate diagnostic sensitivity and specificity. Results did not identify a single assay demonstrating the highest analytical and diagnostic performance characteristics, but revealed strengths and weaknesses of each test.

The Structure of Performance of a Sport Rock Climber

PubMed Central

Magiera, Artur; Roczniok, Robert; Maszczyk, Adam; Czuba, Miłosz; Kantyka, Joanna; Kurek, Piotr

2013-01-01

This study is a contribution to the discussion about the structure of performance of sport rock climbers. Because of the complex and multifaceted nature of this sport, multivariate statistics were applied in the study. The subjects included thirty experienced sport climbers. Forty three variables were scrutinised, namely somatic characteristics, specific physical fitness, coordination abilities, aerobic and anaerobic power, technical and tactical skills, mental characteristics, as well as 2 variables describing the climber’s performance in the OS (Max OS) and RP style (Max RP). The results show that for training effectiveness of advanced climbers to be thoroughly analysed and examined, tests assessing their physical, technical and mental characteristics are necessary. The three sets of variables used in this study explained the structure of performance similarly, but not identically (in 38, 33 and 25%, respectively). They were also complementary to around 30% of the variance. The overall performance capacity of a sport rock climber (Max OS and Max RP) was also evaluated in the study. The canonical weights of the dominant first canonical root were 0.554 and 0.512 for Max OS and Max RP, respectively. Despite the differences between the two styles of climbing, seven variables – the maximal relative strength of the fingers (canonical weight = 0.490), mental endurance (one of scales : The Formal Characteristics of Behaviour–Temperament Inventory (FCB–TI; Strelau and Zawadzki, 1995)) (−0.410), climbing technique (0.370), isometric endurance of the fingers (0.340), the number of errors in the complex reaction time test (−0.319), the ape index (−0.319) and oxygen uptake during arm work at the anaerobic threshold (0.254) were found to explain 77% of performance capacity common to the two styles. PMID:23717360

Performance of gas-lubricated nonconforming pivoted-pad journal bearings and a flexibly mounted spiral-groove thrust bearing

NASA Technical Reports Server (NTRS)

Ream, L. W.

1973-01-01

A test program was conducted to determine the performance characteristics of gas-lubricated nonconforming pivoted-pad journal bearings and a spiral-groove thrust bearing designed for the Brayton cycle rotating unit (BRU). Hydrostatic, hybrid (simultaneously hydrostatic and hydrodynamic), and hydrodynamic tests were conducted in argon gas at ambient pressure and temperature ranges representative of hydrostatic operation up to the 10.5-kWe BRU power-generating level. Performance of the gas lubricated bearings is presented, including hydrostatic gas flow rates, bearing clearances, bearing temperatures, and transient performance.

Performance of gas-lubricated cruciform-mounted tilting-pad journal bearings and a damped flexibly mounted spiral-groove thrust bearing

NASA Technical Reports Server (NTRS)

Ream, L. W.

1974-01-01

A test program was conducted to determine the performance characteristics of gas-lubricated cruciform-mounted tilting-pad journal bearings and a damped spiral-groove thrust bearing designed for the Brayton cycle rotating unit (BRU). Hydrostatic, hybrid (simultaneously hydrostatic and hydrodynamic), and hydrodynamic tests were conducted in argon gas at ambient pressure and temperature ranges representative of operation to the 10.5 kWe BRU power-generating level. Performance of the gas lubricated bearings is presented including hydrostatic gas flow rates, bearing clearances, bearing temperatures, and transient performance.

Long-term monitoring of experimental features, subtask 2 : Alexandria-Ashland highway (KY 9) pavement performance monitoring

DOT National Transportation Integrated Search

2000-06-01

Construction on the AA Highway began in late 1985 and was completed in late 1990. Prior to construction, 30 different test sections had been designed into the highway for evaluation. The test sections contain 23 different characteristic qualities and...

Statewide Physical Fitness Testing: A BIG Waist or a BIG Waste?

ERIC Educational Resources Information Center

Morrow, James R., Jr.; Ede, Alison

2009-01-01

Statewide physical fitness testing is gaining popularity in the United States because of increased childhood obesity levels, the relations between physical fitness and academic performance, and the hypothesized relations between adult characteristics and childhood physical activity, physical fitness, and health behaviors. Large-scale physical…

Properties of asphalt cement used in Virginia and their effects on pavement performance : interim report, task 1, evaluation of asphalt characteristics.

DOT National Transportation Integrated Search

1984-01-01

Results of usual tests for specification compliance and special tests to show viscosity-temperature susceptibility and ductility penetration relationships for asphalts supplied for use by the Virginia Department of Highways and Transportation in 1983...

40 CFR 53.52 - Leak check test.

Code of Federal Regulations, 2014 CFR

2014-07-01

... MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM 2.5 or PM 10-2.5 § 53.52... to include the facility, including components, instruments, operator controls, a written procedure...

Entry characteristics and performance in a Masters module in Tropical Medicine: a 5-year analysis.

PubMed

Weigel, R; Robinson, D; Stewart, M; Assinder, S

2016-06-01

Postgraduate courses can contribute to better-qualified personnel in resource-limited settings. We aimed to identify how entry characteristics of applicants predict performance in order to provide support measures early. We describe demographic data and end-of-module examination marks of medical doctors who enrolled in a first semester module of two one-year MSc programmes between 2010 and 2014. We used t-tests and one-way anova to compare, and post hoc tests to locate differences of mean marks between categories of entry characteristics in univariate analysis. After exclusion of collinear variables, multiple regression examined the effect of several characteristics in multivariable analysis. Eighty-nine students (47% male) with a mean age of 32 (SD 6.4) years who received their medical degree in the UK (19%), other European (22%), African (35%) or other countries (24%) attended the 3-months module. Their mean mark was 69.1% (SD 10.9). Medical graduates from UK universities achieved significantly higher mean marks than graduates from other countries. Students' age was significantly negatively correlated with the module mark. In multiple linear regression, place of medical degree (β = -0.44, P < 0.001) and time since graduation (β = -0.28, P = 0.007) were strongest predictors of performance, explaining 32% of the variation of mean marks. Students' performance substantially differs based on their entry criteria in this 1st semester module. Non-UK graduates and mature students might benefit from early support. © 2016 John Wiley & Sons Ltd.

Inverter performance comparison at PVUSA

NASA Astrophysics Data System (ADS)

Farmer, Brian K.; Stolte, Walter J.; Reyes, Antonio B.

1996-01-01

The paper is a summary of the Photovoltaics for Utility Scale Applications (PVUSA) Project's experience with procurement, testing, operation and maintenance of photovoltaic (PV) power conditioning units (PCUs) at the PVUSA Davis and Kerman sites. Brief descriptions of each of five different PCU models are included to explain tests and operational characteristics. A comparison of the PCUs' performances is presented, and conclusions are offered. Further details are in a forthcoming PVUSA report on PCUs and Power Quality [1].

Performance Characteristics of Lithium Ion Prototype Cells for 2003 Mars Sample Return Athena Rover

NASA Technical Reports Server (NTRS)

Ratnakumar, B. V.; Smart, M. C.; Ewell, R.; Surampudi, S.; Marsh, R. A.

2000-01-01

A viewgraph presentation outlines the mission objectives and power subsystem for the Mars Sample Return (MSR) Athena Rover. The NASA-DOD (depth of discharge) Interagency Li Ion program objectives are discussed. Evaluation tests performed at JPL are listed, and test results are shown for the Li-Ion cell initial capacity, charge/discharge capacity, voltage and ratio, specific energy, watt-hour efficiency, and cell voltage at various temperatures.

Survival of the fittest: implications of self-reliance and coping for leaders and team performance.

PubMed

Daus, C S; Joplin, J R

1999-01-01

Using a laboratory methodology, the authors sought to establish an association between self-reliance (based on attachment theory) and team performance and satisfaction. Three hypotheses (direct effect, mediator, and moderator) were tested. With a sample of 187 students, the authors compared leader self-reliance characteristics with group member self-reliance characteristics (group n = 50) as predictors of group performance and satisfaction. Only group member counterdependence was predictive of decreased performance. Further, the authors examined the possible mediating and moderating effects of coping on the self-reliance-group effectiveness relationships. Coping did not mediate the relationship but did operate as a significant moderator in some instances.

Traceable Calibration, Performance Metrics, and Uncertainty Estimates of Minirhizotron Digital Imagery for Fine-Root Measurements

PubMed Central

Roberti, Joshua A.; SanClements, Michael D.; Loescher, Henry W.; Ayres, Edward

2014-01-01

Even though fine-root turnover is a highly studied topic, it is often poorly understood as a result of uncertainties inherent in its sampling, e.g., quantifying spatial and temporal variability. While many methods exist to quantify fine-root turnover, use of minirhizotrons has increased over the last two decades, making sensor errors another source of uncertainty. Currently, no standardized methodology exists to test and compare minirhizotron camera capability, imagery, and performance. This paper presents a reproducible, laboratory-based method by which minirhizotron cameras can be tested and validated in a traceable manner. The performance of camera characteristics was identified and test criteria were developed: we quantified the precision of camera location for successive images, estimated the trueness and precision of each camera's ability to quantify root diameter and root color, and also assessed the influence of heat dissipation introduced by the minirhizotron cameras and electrical components. We report detailed and defensible metrology analyses that examine the performance of two commercially available minirhizotron cameras. These cameras performed differently with regard to the various test criteria and uncertainty analyses. We recommend a defensible metrology approach to quantify the performance of minirhizotron camera characteristics and determine sensor-related measurement uncertainties prior to field use. This approach is also extensible to other digital imagery technologies. In turn, these approaches facilitate a greater understanding of measurement uncertainties (signal-to-noise ratio) inherent in the camera performance and allow such uncertainties to be quantified and mitigated so that estimates of fine-root turnover can be more confidently quantified. PMID:25391023

Mechanical and wear characteristics of epoxy composites filled with industrial wastes: A comparative study

NASA Astrophysics Data System (ADS)

Purohit, A.; Satapathy, A.

2017-02-01

Use of industrial wastes, such as slag and sludge particles, as filler in polymers is not very common in the field of composite research. Therefore in this paper, a comparison of mechanical characteristics of epoxy based composites filled with LD sludge, BF slag and LD slag (wastes generated in iron and steel industries) were presented. A comparative study among these composites in regard to their dry sliding wear characteristics under similar test conditions was also included. Composites with different weight proportions (0, 5, 10, 15 and 20 wt.%) of LD sludge were fabricated by solution casting technique. Mechanical properties were evaluated as per ASTM test standards and sliding wear test was performed following a design of experiment approach based on Taguchi’s orthogonal array. The test results for epoxy-LD sludge composites were compared with those of epoxy-BF slag and epoxy-LD slag composites reported by previous investigators. The comparison reveals that epoxy filled with LD sludge exhibits superior mechanical and wear characteristics among the three types of composites considered in this study.

Association between older driver characteristics, on-road driving test performance, and crash liability.

PubMed

Keall, Michael D; Frith, William J

2004-06-01

From May 1999, a new system for licensing older drivers was introduced in New Zealand. It included a practical on-road driving test with expanded scope, to be completed every two years from the time the driver turns 80. The relationship between crashes and test performance needed to be studied to inform the debate regarding the testing system. The population studied was all drivers who entered this licensing system during its first three years of operation. They were defined as crash involved if they were involved in an injury crash during the two years following their first licensure under the new system. Logistic regression was used to describe the risk of crash involvement in terms of driving test performance and other driver characteristics. Each driving test failure was associated with a 33% increase in the odds of crash involvement (95% CI 14% to 55%), controlling for age, gender, minor traffic violations, and whether the older driver lived with another licensed driver or not. Minor traffic violations in the two years following the driving test were associated with twice the odds of crash involvement. These results suggest that the new on-road driving test does identify older driver behaviors or limitations that are related to crash liability. It is anticipated that the results presented here will provide essential information for discussing older driver licensing systems, whose impact will grow in importance as the population of drivers ages.

Assessment of burning characteristics of aircraft interior materials

NASA Technical Reports Server (NTRS)

Grand, A. F.; Valys, A. J.

1981-01-01

The performance of a series of seat cushion design constructions was compared based on their heat and smoke release characteristics. Tests were conducted in a room size calorimeter instrumented for measuring weight loss, rate of heat release, smoke and volatile decomposition products and the cumulative energy release. Baseline data were obtained from burn tests conducted on commercial airline salvage sets as a comparison with more advanced seat designs. A toxicological assessment of smoke and fire gases involved the exposure of test animals and their biological responses ascertained. Relative toxicological hazards of the combustion gases are discussed based on the animal response studies and the analysis of the combustion gases.

Microfog lubricant application system for advanced turbine engine components, phase 3. [wetting characteristics and deposit forming tendencies of lubricants

NASA Technical Reports Server (NTRS)

Petrucco, R. J.; Leonardi, S. J.

1973-01-01

The wetting characteristics and deposit forming tendencies of a series of lubricants were evaluated using a microfog jet delivery system to wet a flat heated rotating disc. The performances of the nine lubricants are discussed in terms of the various testing parameters which include temperature, disc speed and lubricant gas flow rates. Also discussed are the heat transfer characteristics of two of the lubricants on that same plane disc specimen. The wetting characteristics and heat transfer characteristics of one of the lubricants on a complex disc simulating bearing geometry are also discussed.

Whole bone mechanics and bone quality.

PubMed

Cole, Jacqueline H; van der Meulen, Marjolein C H

2011-08-01

The skeleton plays a critical structural role in bearing functional loads, and failure to do so results in fracture. As we evaluate new therapeutics and consider treatments to prevent skeletal fractures, understanding the basic mechanics underlying whole bone testing and the key principles and characteristics contributing to the structural strength of a bone is critical. We therefore asked: (1) How are whole bone mechanical tests performed and what are the key outcomes measured? (2) How do the intrinsic characteristics of bone tissue contribute to the mechanical properties of a whole bone? (3) What are the effects of extrinsic characteristics on whole bone mechanical behavior? (4) Do environmental factors affect whole bone mechanical properties? We conducted a PubMed search using specific search terms and limiting our included articles to those related to in vitro testing of whole bones. Basic solid mechanics concepts are summarized in the context of whole bone testing and the determinants of whole bone behavior. Whole bone mechanical tests measure structural stiffness and strength from load-deformation data. Whole bone stiffness and strength are a function of total bone mass and the tissue geometric distribution and material properties. Age, sex, genetics, diet, and activity contribute to bone structural performance and affect the incidence of skeletal fractures. Understanding and preventing skeletal fractures is clinically important. Laboratory tests of whole bone strength are currently the only measures for in vivo fracture prediction. In the future, combined imaging and engineering models may be able to predict whole bone strength noninvasively.

Predicting One Mile and Two Mile Run Performance from Physiological Measures.

ERIC Educational Resources Information Center

Sucec, A. A.

Twenty-three male distance runners between the ages of 16 and 23 who had achieved a ten-minute or better two-mile performance were tested to determine physical and physiological characteristics to be used in predictive research regarding running performance. Relative body fat ratio, metabolic data, and oxygen intake capability were among the…

A One System Integrated Approach to Simulant Selection for Hanford High Level Waste Mixing and Sampling Tests - 13342

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

Thien, Mike G.; Barnes, Steve M.

2013-07-01

The Hanford Tank Operations Contractor (TOC) and the Hanford Waste Treatment and Immobilization Plant (WTP) contractor are both engaged in demonstrating mixing, sampling, and transfer system capabilities using simulated Hanford High-Level Waste (HLW) formulations. This represents one of the largest remaining technical issues with the high-level waste treatment mission at Hanford. Previous testing has focused on very specific TOC or WTP test objectives and consequently the simulants were narrowly focused on those test needs. A key attribute in the Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 2010-2 is to ensure testing is performed with a simulant that represents the broadmore » spectrum of Hanford waste. The One System Integrated Project Team is a new joint TOC and WTP organization intended to ensure technical integration of specific TOC and WTP systems and testing. A new approach to simulant definition has been mutually developed that will meet both TOC and WTP test objectives for the delivery and receipt of HLW. The process used to identify critical simulant characteristics, incorporate lessons learned from previous testing, and identify specific simulant targets that ensure TOC and WTP testing addresses the broad spectrum of Hanford waste characteristics that are important to mixing, sampling, and transfer performance are described. (authors)« less

Safety characteristics of the lithium SO2 system

NASA Technical Reports Server (NTRS)

Watson, T.

1978-01-01

Extensive tests were conducted to quantitatively define the safety characteristics of high-rate SO2 multicell batteries under various discharge and temperature profiles, which closely simulated actual field-use conditions. The resulting behavior patters of the multicell batteries and the corrective action which can be implemented to minimize or prevent hazardous battery performance are briefly summarized.

Performance Characteristic Mems-Based IMUs for UAVs Navigation

NASA Astrophysics Data System (ADS)

Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

2015-08-01

Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

Time-Dependent Testing Evaluation and Modeling for Rubber Stopper Seal Performance.

PubMed

Zeng, Qingyu; Zhao, Xia

2018-01-01

Sufficient rubber stopper sealing performance throughout the entire sealed product life cycle is essential for maintaining container closure integrity in the parenteral packaging industry. However, prior publications have lacked systematic considerations for the time-dependent influence on sealing performance that results from the viscoelastic characteristics of the rubber stoppers. In this paper, we report results of an effort to study these effects by applying both compression stress relaxation testing and residual seal force testing for time-dependent experimental data collection. These experiments were followed by modeling fit calculations based on the Maxwell-Wiechert theory modified with the Kohlrausch-Williams-Watts stretched exponential function, resulting in a nonlinear, time-dependent sealing force model. By employing both testing evaluations and modeling calculations, an in-depth understanding of the time-dependent effects on rubber stopper sealing force was developed. Both testing and modeling data show good consistency, demonstrating that the sealing force decays exponentially over time and eventually levels off because of the viscoelastic nature of the rubber stoppers. The nonlinearity of stress relaxation derives from the viscoelastic characteristics of the rubber stoppers coupled with the large stopper compression deformation into restrained geometry conditions. The modeling fit with capability to handle actual testing data can be employed as a tool to calculate the compression stress relaxation and residual seal force throughout the entire sealed product life cycle. In addition to being time-dependent, stress relaxation is also experimentally shown to be temperature-dependent. The present work provides a new, integrated methodology framework and some fresh insights to the parenteral packaging industry for practically and proactively considering, designing, setting up, controlling, and managing stopper sealing performance throughout the entire sealed product life cycle. LAY ABSTRACT: Historical publications in the parenteral packaging industry have lacked systematic considerations for the time-dependent influence on the sealing performance that results from effects of viscoelastic characteristic of the rubber stoppers. This study applied compression stress relaxation testing and residual seal force testing for time-dependent experimental data collection. These experiments were followed by modeling fit calculations based on the Maxwell-Wiechert theory modified with the Kohlrausch-Williams-Watts stretched exponential function, resulting in a nonlinear, time-dependent sealing force model. Experimental and modeling data show good consistency, demonstrating that sealing force decays exponentially over time and eventually levels off. The nonlinearity of stress relaxation derives from the viscoelastic characteristics of the rubber stoppers coupled with the large stopper compression deformation into restrained geometry conditions. In addition to being time-dependent stress relaxation, it is also experimentally shown to be temperature-dependent. The present work provides a new, integrated methodology framework and some fresh insights to the industry for practically and proactively considering, designing, setting up, controlling, and managing of the stopper sealing performance throughout the entire sealed product life cycle. © PDA, Inc. 2018.

Performance Characterization of the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) CCD Cameras

NASA Technical Reports Server (NTRS)

Joiner, Reyann; Kobayashi, Ken; Winebarger, Amy; Champey, Patrick

2014-01-01

The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a sounding rocket instrument currently being developed by NASA's Marshall Space Flight Center (MSFC), the National Astronomical Observatory of Japan (NAOJ), and other partners. The goal of this instrument is to observe and detect the Hanle effect in the scattered Lyman-Alpha UV (121.6nm) light emitted by the Sun's chromosphere. The polarized spectrum imaged by the CCD cameras will capture information about the local magnetic field, allowing for measurements of magnetic strength and structure. In order to make accurate measurements of this effect, the performance characteristics of the three on- board charge-coupled devices (CCDs) must meet certain requirements. These characteristics include: quantum efficiency, gain, dark current, read noise, and linearity. Each of these must meet predetermined requirements in order to achieve satisfactory performance for the mission. The cameras must be able to operate with a gain of 2.0+/- 0.5 e--/DN, a read noise level less than 25e-, a dark current level which is less than 10e-/pixel/s, and a residual non- linearity of less than 1%. Determining these characteristics involves performing a series of tests with each of the cameras in a high vacuum environment. Here we present the methods and results of each of these performance tests for the CLASP flight cameras.

Relationship of Academic Job Involvement To Biographical Data, Personal Characteristics, and Academic Performance.

ERIC Educational Resources Information Center

Edwards, Jack E.; Waters, L. K.

1980-01-01

A job involvement measure adapted to reflect course involvement was unrelated to age, sex, class rank, and tested verbal ability. However, it was significantly and positively related to achievement motivation, locus of control, Protestant ethic attitudes, academic satisfaction, and performance. (Author/CP)

Spherical roller bearing analysis. SKF computer program SPHERBEAN. Volume 3: Program correlation with full scale hardware tests

NASA Technical Reports Server (NTRS)

Kleckner, R. J.; Rosenlieb, J. W.; Dyba, G.

1980-01-01

The results of a series of full scale hardware tests comparing predictions of the SPHERBEAN computer program with measured data are presented. The SPHERBEAN program predicts the thermomechanical performance characteristics of high speed lubricated double row spherical roller bearings. The degree of correlation between performance predicted by SPHERBEAN and measured data is demonstrated. Experimental and calculated performance data is compared over a range in speed up to 19,400 rpm (0.8 MDN) under pure radial, pure axial, and combined loads.

A simple bedside blood test (Fibrofast; FIB-5) is superior to FIB-4 index for the differentiation between non-significant and significant fibrosis in patients with chronic hepatitis C.

PubMed

Shiha, G; Seif, S; Eldesoky, A; Elbasiony, M; Soliman, R; Metwally, A; Zalata, K; Mikhail, N

2017-05-01

A simple non-invasive score (Fibrofast, FIB-5) was developed using five routine laboratory tests (ALT, AST, alkaline phosphatase, albumin and platelets count) for the detection of significant hepatic fibrosis in patients with chronic hepatitis C. The FIB-4 index is a non-invasive test for the assessment of liver fibrosis, and a score of ≤1.45 enables the correct identification of patients who have non-significant (F0-1) from significant fibrosis (F2-4), and could avoid liver biopsy. The aim of this study was to compare the performance characteristics of FIB-5 and FIB-4 to differentiate between non-significant and significant fibrosis. A cross-sectional study included 604 chronic HCV patients. All liver biopsies were scored using the METAVIR system. Both FIB-5 and FIB-4 scores were measured and the performance characteristics were calculated using the ROC curve. The performance characteristics of FIB-5 at ≥7.5 and FIB-4 at ≤1.45 for the differentiation between non-significant fibrosis and significant fibrosis were: specificity 94.4%, PPV 85.7%, and specificity 54.9%, PPV 55.7% respectively. FIB-5 score at the new cutoff is superior to FIB-4 index for the differentiation between non-significant and significant fibrosis.

Assessment of the pharmacodynamics of intranasal, intravenous and oral scopolamine

NASA Technical Reports Server (NTRS)

Tietze, Karen J.

1990-01-01

Space motion sickness is an important issue in the space medical sciences program. One of the objectives of the ongoing clinical experimental protocol Pharmacokinetics of Intranasal Scopolamine in Normal Subjects is to evaluate the pharmacodynamics of scopolamine using salivary flow rate and pH profiles and cognitive performance tests as pharmacodynamic parameters. Normal volunteers collected saliva and performed the NTI Multiresource Performance Battery tests at designed time intervals to establish control saliva flow rates, salivary pH profiles, and the characteristics of the learning curve for the performance program under normal conditions. In the clinical part of the study, saliva samples and performance test scores are collected from healthy nonsmoking subjects after receiving a single 0.4 mg dose of either intranasal, intravenous, or oral scopolamine.

Performance Characterization of a Microchannel Liquid/Liquid Heat Exchanger Throughout an Extended Duration Life Test

NASA Technical Reports Server (NTRS)

Sheth, Rubik B.; Stephan, Ryan A.; Hawkins-Reynolds Ebony

2011-01-01

Liquid/Liquid Heat Exchangers (L/L HX) are an integral portion of any spacecraft active thermal control system. For this study the X-38 L/L HX was used as a baseline. As detailed in a previous ICES manuscript, NASA paired with Pacific Northwest National Laboratory to develop a Microchannel L/L HX (MHX). This microchannel HX was designed to meet the same performance characteristics as the aforementioned X-38 HX. The as designed Microchannel HX has a 26% and 60% reduction in mass and volume, respectively. Due to the inherently smaller flow passages the design team was concerned about fouling affecting performance during extended missions. To address this concern, NASA has developed a test stand and is currently performing an 18 month life test on the MHX. This report will detail the up-to-date performance of the MHX during life testing.

Overview of 10 inch Diameter HTPB Hybrid Motor Testing with Liquid Oxygen at Stennis Space Center

NASA Technical Reports Server (NTRS)

Knowles, Timothy E.; Kearney, Darren; Roberts, Ryan

2005-01-01

To further explore the operation of hybrid rocket motors and to demonstrate the performance characteristics of the motor design Lockheed Martin funded research on a series of 10 inch diameter hybrid motors that produce less than 10 klbf sea level thrust. This test series was given the name "Hybrid Technology Test Program." These motors were fired in the existing test stand at the SSC E-3 complex Cell 1. The fuel and oxidizer for these 10 inch diameter motors are HTPB and LO2, respectively. The original goal of the testing was to verify that the predicted performance matched the actual performance of these 10 inch motors (ref. figure 1) and then confirm that the motors performed acceptably. For this element of testing horizontally fired hybrid motors will be tested using LO2 supplied from the existing facility 100 gallon LO2 tank that is pressurized with facility GN2. The thrust produced by the motor will be measured by a Lockheed Martin supplied load cell.

Engineering evaluation of SSME dynamic data from engine tests and SSV flights

NASA Technical Reports Server (NTRS)

1986-01-01

An engineering evaluation of dynamic data from SSME hot firing tests and SSV flights is summarized. The basic objective of the study is to provide analyses of vibration, strain and dynamic pressure measurements in support of MSFC performance and reliability improvement programs. A brief description of the SSME test program is given and a typical test evaluation cycle reviewed. Data banks generated to characterize SSME component dynamic characteristics are described and statistical analyses performed on these data base measurements are discussed. Analytical models applied to define the dynamic behavior of SSME components (such as turbopump bearing elements and the flight accelerometer safety cut-off system) are also summarized. Appendices are included to illustrate some typical tasks performed under this study.

Performance Evaluation of the International Space Station Flow Boiling and Condensation Experiment (FBCE) Test Facility

NASA Technical Reports Server (NTRS)

Hasan, Mohammad; Balasubramaniam, R.; Nahra, Henry; Mackey, Jeff; Hall, Nancy; Frankenfield, Bruce; Harpster, George; May, Rochelle; Mudawar, Issam; Kharangate, Chirag R.;

NASA Lewis and Ohio Company Hit Hole in One

NASA Technical Reports Server (NTRS)

1998-01-01

Ben Hogan Company's Golf Ball Division, which is based in Elyria, Ohio, had developed concepts and prototypes for new golf balls but was unable to determine exact performance characteristics. Specifically, the company's R&D department wanted to measure the spin rates of experimental golf balls. After the Golf Ball Division requested assistance, researchers and technicians from the NASA Lewis Research Center went to Elyria and conducted several days worth of tests. Ben Hogan is using the test results to improve the spin characteristics of a new ball it plans to introduce to the market.

Deep flaws in weldments of aluminum and titanium

NASA Technical Reports Server (NTRS)

Masters, J. N.; Engstrom, W. L.; Bixler, W. D.

1974-01-01

Surface flawed specimens of 2219-T87 and 6Al-4V STA titanium weldments were tested to determine static failure modes, failure strength, and fatigue flaw growth characteristics. Thicknesses selected for this study were purposely set at values where, for most test conditions, abrupt instability of the flaw at fracture would not be expected. Static tests for the aluminum weldments were performed at room, LN2 and LH2 temperatures. Titanium static tests for tests were performed at room and LH2 temperatures. Results of the static tests were used to plot curves relating initial flaw size to leakage- or failure-stresses (i.e. "failure" locus curves). Cyclic tests, for both materials, were then performed at room temperature, using initial flaws only slightly below the previously established failure locus for typical proof stress levels. Cyclic testing was performed on pairs of specimens, one with and one without a simulated proof test cycle. Comparisons were made then to determine the value and effect of proof testing as affected by the various variables of proof and operating stress, flaw shape, material thickness, and alloy.

FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS VOLUME III. FIELD EVALUATIONS

EPA Science Inventory

The report gives results of field tests conducted to determine the emission characteristics of a Babcock and Wilcox Circular burner and Dual Register burner (DRB). The field tests were performed at two utility boilers, generally comparable in design and size except for the burner...

Multi-Method Assessment of ADHD Characteristics in Preschool Children: Relations between Measures

ERIC Educational Resources Information Center

Sims, Darcey M.; Lonigan, Christopher J.

2012-01-01

Several forms of assessment tools, including behavioral rating scales and objective tests such as the Continuous Performance Test (CPT), can be used to measure inattentive and hyperactive/impulsive behaviors associated with Attention-Deficit/Hyperactivity Disorder (ADHD). However, research with school-age children has shown that the correlations…

40 CFR 53.52 - Leak check test.

Code of Federal Regulations, 2011 CFR

2011-07-01

... MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 § 53.52... to include the facility, including components, instruments, operator controls, a written procedure...

40 CFR 53.52 - Leak check test.

Code of Federal Regulations, 2012 CFR

2012-07-01

... MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 § 53.52... to include the facility, including components, instruments, operator controls, a written procedure...

40 CFR 53.52 - Leak check test.

Code of Federal Regulations, 2010 CFR

2010-07-01

... MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 § 53.52... to include the facility, including components, instruments, operator controls, a written procedure...

Correlation and evaluation of inplane stability characteristics for an advanced bearingless main rotor

NASA Technical Reports Server (NTRS)

Weller, W. H.

1983-01-01

A program of experimental and analytical research was performed to demonstrate the degree of correlation achieved between measured and computed rotor inplane stability characteristics. The experimental data were obtained from hover and wind tunnel tests of a scaled bearingless main rotor model. Both isolated rotor and free-hub conditions were tested. Test parameters included blade built-in cone and sweep angles; rotor inplane structural stiffness and damping; pitch link stiffness and location; and fuselage damping, inertia, and natural frequency. Analytical results for many test conditions were obtained. In addition, the analytical and experimental results were examined to ascertain the effects of the test parameters on rotor ground and air resonance stability. The results from this program are presented herein in tabular and graphical form.

Structural Test and Analysis of a Hybrid Inflatable Antenna

NASA Technical Reports Server (NTRS)

Gaspar, James L.; Mann, Troy; Sreekantamurthy, Tham; Behun, Vaughn

2007-01-01

NASA is developing ultra-lightweight structures technology for communication antennas for space missions. One of the research goals is to evaluate the structural characteristics of inflatable and rigidizable antennas through test and analysis. Being able to test and analyze the structural characteristics of a full scale antenna is important to enable the simulation of various mission scenarios to determine system performance in space. Recent work completed to evaluate a Hybrid Inflatable Antenna concept will be discussed. Tests were completed on a 2-m prototype to optimize its static shape and identify its modal dynamics that are important for analytical model validation. These test results were used to evaluate a preliminary finite element model of the antenna, and this model development and correlation activity is also described in the paper.

A 2000-Hour Durability Test of a 5-Centimeter Diameter Mercury Bombardment Ion Thruster

NASA Technical Reports Server (NTRS)

Nakanishi, S.; Finke, R. G.

1972-01-01

A 2000-hour durability test of a modified Hughes SIT-5 (Structurally Integrated Thruster, 5 cm) was conducted at the Lewis Research Center. The thruster operated with a translating screen thrust vector grid locked in position for 10 deg beam deflection. The test was essentially continuous except for seven stoppages of beam current. The neutralizer keeper voltage and thruster floating potential increased slightly with time. Performance profiles and maps of thruster characteristics were obtained at 453 and 2023 hours into the test. Overall efficiency was nearly constant at 31 - 32 percent, and operating characteristics were similar at both points in the test. A post-shutdown inspection showed negligible erosion damage to the accelerator and cathode baffle. Some erosion was found in the aperture of the neutralizer cathode.

Low speed wind tunnel test of a propulsive wing/canard concept in the STOL configuration. Volume 2: Test data

NASA Technical Reports Server (NTRS)

Stewart, V. R.

1987-01-01

A propulsive wind/canard model was tested at STOL operating conditions in the NASA Langley Research Center 4 x 7 meter wind tunnel. Longitudinal and lateral/directional aerodynamic characteristics were measured for various flap deflections, angles of attack and sideslip, and blowing coefficients. Testing was conducted for several model heights to determine ground proximity effects on the aerodynamic characteristics. Flow field surveys of local flow angles and velocities were performed behind both the canard and the wing. This is volume 2 of a 2 volume report. All of the test data in three appendices are presented. Appendix A presented tabulated six component force and moment data, Appendix B presents tabulated wing pressure coefficients, and Appendix C presents the flow field data.

Testing some major determinants for hospital innovation success.

PubMed

Caccia-Bava, Maria do Carmo; Guimaraes, Valerie C K; Guimaraes, Tor

2009-01-01

Hospitals have adopted new policies, methods and technologies to change their processes, improve services, and support other organizational changes necessary for better performance. The literature regarding the four major areas of strategic leadership, competitive intelligence, management of technology, and specific characteristics of the organization's change process propose their importance in successfully implementing organization innovation. While these factors may indeed be important to enhance hospital performance, the existing literature contains limited empirical evidence supporting their relationship to successfully implementing innovation in hospitals. This study aims to empirically test these relationships proposed in the literature by researchers in separate knowledge areas. A survey of 223 hospitals has been used to test an integrated model of these relationships. The response rate and the representativeness of the sample in terms of hospital size and geographical location were found satisfactory. The quality assurance/compliance managers for each hospital were the target respondents to questions, which require a corporate perspective while reducing the chance of bias for questions regarding top management leadership abilities. The results provide clear evidence about the importance of strategic leadership, competitive intelligence, management of technology, and specific characteristics of the hospital's change process to the hospitals success in implementing innovation. Given the importance of hospitals to change their processes, improve services, and support other organizational changes necessary for better performance, a great benefit is that the main factors for successful innovation have been brought together from scattered literature and tested among hospitals. Further, the items used for measuring the main constructs provide further insights into how hospital administrators should go about developing these areas within their organizations. This study is a first attempt at empirically testing the importance of strategic leadership, competitive intelligence, management of technology, and specific characteristics of the hospital's change process for the success of innovation efforts.

Evaluation of Data Retention and Imprint Characteristics of FRAMs Under Environmental Stresses for NASA Applications

NASA Technical Reports Server (NTRS)

Sharma, Ashok K.; Teverovsky, Alexander; Dowdy, Terry W.; Hamilton, Brett

2000-01-01

A major reliability issue for all advanced nonvolatile memory (NVM) technology devices including FRAMs (Ferroelectric random access memories) is the data retention characteristics over extended period of time, under environmental stresses and exposure to total ionizing dose (TID) radiation effects. For this testing, 256 Kb FRAMs in 28-pin plastic DIPS, rated for industrial grade temperature range of -40 C to +85 C, were procured. These are two-transistor, two-capacitor (2T-2C) design FRAMs. In addition to data retention characteristics, the parts were also evaluated for imprint failures, which are defined as the failure of cells to change from a "preferred" state, where it has been for a significant period of time to an opposite state (e.g., from 1 to 0, or 0 to 1). These 256 K FRAMs were subjected to scanning acoustic microscopy (C-SAM); 1,000 temperature cycles from -65 C to +150 C; high temperature aging at 150 C, 175 C, and 200 C for 1,000 hours; highly accelerated stress test (HAST) for 500 hours; 1,000 hours of operational life test at 125 C; and total ionizing dose radiation testing. As a preconditioning, 10 K read/write cycles were performed on all devices. Interim electrical measurements were performed throughout this characterization, including special imprint testing and final electrical testing. Some failures were observed during high temperature aging test at 200 C, during HAST testing, and during 1,000 hours of operational life at 125 C. The parts passed 10 Krad exposure, but began showing power supply current increases during the dose increment from 10 Krad to 30 Krad, and at 40 Krad severe data retention and parametric failures were observed. Failures from various environmental group testing are currently being analyzed.

Evaluation of Data Retention and Imprint Characteristics of FRAMs Under Environmental Stresses for NASA Applications

NASA Technical Reports Server (NTRS)

Sharma, Asbok K.; Teverovsky, Alexander; Dowdy, Terry W.; Hamilton, Brett

2002-01-01

A major reliability issue for all advanced nonvolatile memory (NVM) technology devices including FRAMs is the data retention characteristics over extended period of time, under environmental stresses and exposure to total ionizing dose (TID) radiation effects. For this testing, 256 Kb FRAMs in 28-pin plastic DIPS, rated for industrial grade temperature range of -40 C to +85 C, were procured. These are two-transistor, two-capacitor (2T-2C) design FRAMs. In addition to data retention characteristics, the parts were also evaluated for imprint failures, which are defined as the failure of cells to change from a "preferred" state, where it has been for a significant period of time to an opposite state (e.g., from 1 to 0, or 0 to 1). These 256 K FRAMs were subjected to scanning acoustic microscopy (C-SAM); 1,000 temperature cycles from -65 C to +150 C; high temperature aging at 150 C, 175 C, and 200 C for 1,000 hours; highly accelerated stress test (HAST) for 500 hours; 1,000 hours of operational life test at 125 C; and total ionizing dose radiation testing. As a preconditioning, 10 K read/write cycles were performed on all devices. Interim electrical measurements were performed throughout this characterization, including special imprint testing and final electrical testing. Some failures were observed during high temperature aging test at 200 C, during HAST testing, and during 1,000 hours of operational life at 125 C. The parts passed 10 Krad exposure, but began showing power supply current increases during the dose increment from 10 Krad to 30 Krad, and at 40 Krad severe data retention and parametric failures were observed. Failures from various environmental group testing are currently being analyzed.

A Systematic Review of the Reliability and Validity of Behavioural Tests Used to Assess Behavioural Characteristics Important in Working Dogs.

PubMed

Brady, Karen; Cracknell, Nina; Zulch, Helen; Mills, Daniel Simon

2018-01-01

Working dogs are selected based on predictions from tests that they will be able to perform specific tasks in often challenging environments. However, withdrawal from service in working dogs is still a big problem, bringing into question the reliability of the selection tests used to make these predictions. A systematic review was undertaken aimed at bringing together available information on the reliability and predictive validity of the assessment of behavioural characteristics used with working dogs to establish the quality of selection tests currently available for use to predict success in working dogs. The search procedures resulted in 16 papers meeting the criteria for inclusion. A large range of behaviour tests and parameters were used in the identified papers, and so behaviour tests and their underpinning constructs were grouped on the basis of their relationship with positive core affect (willingness to work, human-directed social behaviour, object-directed play tendencies) and negative core affect (human-directed aggression, approach withdrawal tendencies, sensitivity to aversives). We then examined the papers for reports of inter-rater reliability, within-session intra-rater reliability, test-retest validity and predictive validity. The review revealed a widespread lack of information relating to the reliability and validity of measures to assess behaviour and inconsistencies in terminologies, study parameters and indices of success. There is a need to standardise the reporting of these aspects of behavioural tests in order to improve the knowledge base of what characteristics are predictive of optimal performance in working dog roles, improving selection processes and reducing working dog redundancy. We suggest the use of a framework based on explaining the direct or indirect relationship of the test with core affect.

Turbopumps for cryogenic upper stage engines. [fabrication and evaluation of turbine pumps for liquid hydrogen and liquid oxygen

NASA Technical Reports Server (NTRS)

Zachary, A. T.; Csomor, A.; Tignac, L. L.

1973-01-01

Small, high-performance LO2 and LH2 turbopump assembly configurations were selected, detail designs were prepared and two of each unit were fabricated with each unit consisting of pump, turbine gas generator, and appropriate controls. Following fabrication, development testing was conducted on each type to demonstrate performance, durability, transient characteristics, and heat transfer under simulated altitude conditions. Following successful completion of development effort, the two LO2 turbopump units and one LH2 turbopump unit were acceptance tested as specified. Inspection of the units following development testing revealed no deleterious effects of testing. The test results of LO2 turbopump assembly testing correlated well with predicted performance while the LH2 turbopump test results, though generally consistent with predicted values, did show lower than anticipated developed head at the design point and in the high flow range of operation.

[Association between the characteristics of coordination development disorder and symptoms of attention deficit disorder with hyperactivity in children in the city of Manizales].

PubMed

Salamanca Duque, Luisa Matilde; Naranjo Aristizábal, María Mercedes; Castro Castro, Ángel Laban; Calle Jaramillo, Guillermo Andrés

2016-01-01

Developmental coordination disorder (DCD) in childhood is an important public health problem, which has important implications for different spheres of development: motor, cognitive, psychosocial and emotional. Therefore, the presence of comorbidity is common, along with other disorders in child development. This article presents a study that determines the association between DCD characteristics with attention deficit and hyperactivity disorder (ADHD) symptoms. To determine the association between DCD characteristics and ADHD symptoms in the city of Manizales, Colombia. Cross-sectional, descriptive and associative study, in a sample of 140 children aged 6-12, randomised in public and private institutions. A structured interview was conducted, along with the questionnaires MINIKID and Cuestionario para Trastorno del Desarrollo de la Coordinación (CTDC). A descriptive univariate analysis was performed on the the sociodemographic characteristics, as well as association tests with χ(2) test, and dependence level with φ coefficient. A statistically significant association was found between the CTDC characteristics with ADHD symptoms (φ=.452; P=.001). An association was found in the studied population between the CTDC characteristics and ADHD symptoms, indicating that children with difficulties in motor performance may also have attention difficulties and hyperactivity. Copyright © 2015 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Solar panel thermal cycling testing by solar simulation and infrared radiation methods

NASA Technical Reports Server (NTRS)

Nuss, H. E.

1980-01-01

For the solar panels of the European Space Agency (ESA) satellites OTS/MAROTS and ECS/MARECS the thermal cycling tests were performed by using solar simulation methods. The performance data of two different solar simulators used and the thermal test results are described. The solar simulation thermal cycling tests for the ECS/MARECS solar panels were carried out with the aid of a rotatable multipanel test rig by which simultaneous testing of three solar panels was possible. As an alternative thermal test method, the capability of an infrared radiation method was studied and infrared simulation tests for the ultralight panel and the INTELSAT 5 solar panels were performed. The setup and the characteristics of the infrared radiation unit using a quartz lamp array of approx. 15 sq and LN2-cooled shutter and the thermal test results are presented. The irradiation uniformity, the solar panel temperature distribution, temperature changing rates for both test methods are compared. Results indicate the infrared simulation is an effective solar panel thermal testing method.

Static internal performance of a two-dimensional convergent nozzle with thrust-vectoring capability up to 60 deg

NASA Technical Reports Server (NTRS)

Leavitt, L. D.

1985-01-01

An investigation was conducted at wind-off conditions in the static-test facility of the Langley 16-Foot Transonic Tunnel to determine the internal performance characteristics of a two-dimensional convergent nozzle with a thrust-vectoring capability up to 60 deg. Vectoring was accomplished by a downward rotation of a hinged upper convergent flap and a corresponding rotation of a center-pivoted lower convergent flap. The effects of geometric thrust-vector angle and upper-rotating-flap geometry on internal nozzle performance characteristics were investigated. Nozzle pressure ratio was varied from 1.0 (jet off) to approximately 5.0.

Performance characteristics of ambient temperature secondary lithium cells

NASA Technical Reports Server (NTRS)

Deligiannis, F.; Shen, D.; Subbarao, S.; Whitcanack, L.; Halpert, G.

1988-01-01

State of art ambient temperature secondary lithium cells were evaluated to determine their performance capability and limitations and to assess the present status of the technology of these cells. Li-MoS2, Li-NbSe3 and Li-TiS2 cells were evaluated for their charge/discharge characteristics, rate capability, and cycle life performance. The cells evaluated have a cycle life of 100-250 cycles at moderate discharge rates (C/5). The specific energy of these cells is between 50 and 100 Wh/Kg, depending upon the system. This paper describes the details of the cell designs, the test procedures, and the results of the evaluation studies.

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

PubMed

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

2017-09-01

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

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

PubMed Central

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

2017-01-01

Abstract Yamashita, D, Asakura, M, Ito, Y, Yamada, S, and Yamada, Y. Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455–2461, 2017—This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (>20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance. PMID:28052052

The Association Between Fall History and Physical Performance Tests in the Community-Dwelling Elderly: A Cross-Sectional Analysis.

PubMed

Kim, Jin Chul; Chon, Jinmann; Kim, Hee Sang; Lee, Jong Ha; Yoo, Seung Don; Kim, Dong Hwan; Lee, Seung Ah; Han, Yoo Jin; Lee, Hyun Seok; Lee, Bae Youl; Soh, Yun Soo; Won, Chang Won

2017-04-01

To evaluate the association between baseline characteristics, three physical performance tests and fall history in a sample of the elderly from Korean population. A total of 307 participants (mean age, 76.70±4.85 years) were categorized into one of two groups, i.e., fallers and non-fallers. Fifty-two participants who had reported falling unexpectedly at least once in the previous 12 months were assigned to the fallers group. Physical performance tests included Short Physical Performance Battery (SPPB), Berg Balance Scale (BBS), Timed Up and Go test. The differences between the two study groups were compared and we analyzed the correlations between fall histories and physical performance tests. SPPB demonstrated a significant association with fall history. Although the BBS total scores did not show statistical significance, two dynamic balance test items of BBS (B12 and B13) showed a significant association among fallers. This study suggests that SPPB and two dynamic balance test items of the BBS can be used in screening for risk of falls in an ambulatory elderly population.

Thermal-environmental testing of a 30-cm engineering model thruster

NASA Technical Reports Server (NTRS)

Mirtich, M. J.

1976-01-01

An experimental test program was carried out to document all 30-cm electron bombardment Hg ion bombardment thruster functions and characteristics over the thermal environment of several proposed missions. An engineering model thruster was placed in a thermal test facility equipped with -196 C walls and solar simulation. The thruster was cold soaked and exposed to simulated eclipses lasting in duration from 17 to 72 minutes. The thruster was operated at quarter, to full beam power in various thermal configurations which simulated multiple thruster operation, and was also exposed to 1 and 2 suns solar simulation. Thruster control characteristics and constraints; performance, including thrust magnitude and direction; and structural integrity were evaluated over the range of thermal environments tested.

Experimental evaluation of battery cells for space-based radar application

NASA Technical Reports Server (NTRS)

Maskell, Craig A.; Metcalfe, John R.

1994-01-01

A test program was conducted to characterize five space-quality nickel-hydrogen (NiH2) battery cells. A subset of those tests was also done on five commercial nickel-cadmium (NiCd) cells, for correlation to the characteristics of an Energy Storage Unit Simulator. The test program implemented the recommendations of a 1991 study, as reported to IECEC-92. The findings of the tests are summarized, and expected impacts on the performance of the electrical power system (EPS) of a large space-based radar (SBR) surveillance satellite are derived. The main characteristics examined and compared were terminal voltage (average and transient) and capacity through discharge, equivalent series resistance, derived inductance and capacitance, charge return efficiency, and inter-pulse charge effectiveness.

Thermal-environment testing of a 30-cm engineering model thruster

NASA Technical Reports Server (NTRS)

Mirtich, M. J.

1976-01-01

An experimental test program was carried out to document all 30-cm electron bombardment Hg ion bombardment thruster functions and characteristics over the thermal environment of several proposed missions. An engineering model thruster was placed in a thermal test facility equipped with -196 C walls and solar simulation. The thruster was cold soaked and exposed to simulated eclipses lasting in duration from 17 to 72 minutes. The thruster was operated at quarter, to full beam power in various thermal configurations which simulated multiple thruster operation, and was also exposed to 1 and 2 suns solar simulation. Thruster control characteristics and constraints; performance, including thrust magnitude and direction; and structural integrity were evaluated over the range of thermal environments tested.

Durability, Performance, and Emission of Diesel Engines Using Carbon Fiber Piston and Liner

NASA Technical Reports Server (NTRS)

Afify, E. M.; Roberts, W. L.

1999-01-01

This report summarizes the research conducted by NC State University in investigating the durability, performance and emission of a carbon fiber piston and liner in our single cylinder research Diesel engine. Both the piston and liner were supplied to NC State University by NASA LaRC and manufactured by C-CAT under a separate contract to NASA LaRC. The carbon-carbon material used to manufacture the piston and liner has significantly lower thermal conductivity, coefficient of thermal expansion, and superior strength characteristics at elevated temperatures when compared to conventional piston materials such as aluminum. The results of the carbon-carbon fiber piston testing were compared to a baseline configuration, which used a conventional aluminum piston in a steel liner. The parameters measured were the brake specific fuel consumption, ignition delay, frictional horsepower, volumetric efficiency, and durability characteristics of the two pistons. Testing was performed using a naturally aspirated Labeco Direct Injection single cylinder diesel engine. Two test cases were performed over a range of loads and speeds. The fixed test condition between the aluminum and carbon-carbon piston configurations was the brake mean effective pressure. The measured data was the fuel consumption rate, volumetric efficiency, load, speed, cylinder pressure, needle lift, and exhaust gas temperature. The cylinder pressure, and fuel consumption, exhaust gas temperature, and needle lift were recorded using a National Instruments DAQ board and a PC. All test cases used Diesel no. 2 for fuel.

Sodium-sulfur Cell Technology Flight Experiment (SSCT)

NASA Technical Reports Server (NTRS)

Halbach, Carl R.

1992-01-01

The sodium-sulfur battery is emerging as a prime high-temperature energy storage technology for space flight applications. A Na-S cell demonstration is planned for a 1995-96 NASA Space Shuttle flight which focuses on the microgravity effects on individual cells. The experiment is not optimized for battery performance as such. Rather, it maximizes the variety of operating conditions which the Na-S cell is capable of in a relatively short 5-day flight. The demonstration is designed to reveal the effects of microgravity by comparison with ground test control cells experiencing identical test conditions but with gravity. Specifically, limitations of transport dynamics and associated cell performance characteristics should be revealed. The Na-S Cell Technology Flight Experiment consists of three separate experiments designed to determine cell operating characteristics, detailed electrode kinetics and reactant distributions.

Uncertainty estimates of purity measurements based on current information: toward a "live validation" of purity methods.

PubMed

Apostol, Izydor; Kelner, Drew; Jiang, Xinzhao Grace; Huang, Gang; Wypych, Jette; Zhang, Xin; Gastwirt, Jessica; Chen, Kenneth; Fodor, Szilan; Hapuarachchi, Suminda; Meriage, Dave; Ye, Frank; Poppe, Leszek; Szpankowski, Wojciech

2012-12-01

To predict precision and other performance characteristics of chromatographic purity methods, which represent the most widely used form of analysis in the biopharmaceutical industry. We have conducted a comprehensive survey of purity methods, and show that all performance characteristics fall within narrow measurement ranges. This observation was used to develop a model called Uncertainty Based on Current Information (UBCI), which expresses these performance characteristics as a function of the signal and noise levels, hardware specifications, and software settings. We applied the UCBI model to assess the uncertainty of purity measurements, and compared the results to those from conventional qualification. We demonstrated that the UBCI model is suitable to dynamically assess method performance characteristics, based on information extracted from individual chromatograms. The model provides an opportunity for streamlining qualification and validation studies by implementing a "live validation" of test results utilizing UBCI as a concurrent assessment of measurement uncertainty. Therefore, UBCI can potentially mitigate the challenges associated with laborious conventional method validation and facilitates the introduction of more advanced analytical technologies during the method lifecycle.

Analytical Performance Characteristics of the Cepheid GeneXpert Ebola Assay for the Detection of Ebola Virus

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

Pinsky, Benjamin A.; Sahoo, Malaya K.; Sandlund, Johanna

The recently developed Xpert® Ebola Assay is a novel nucleic acid amplification test for simplified detection of Ebola virus (EBOV) in whole blood and buccal swab samples. The assay targets sequences in two EBOV genes, lowering the risk for new variants to escape detection in the test. The objective of this report is to present analytical characteristics of the Xpert® Ebola Assay on whole blood samples. Our study evaluated the assay’s analytical sensitivity, analytical specificity, inclusivity and exclusivity performance in whole blood specimens. EBOV RNA, inactivated EBOV, and infectious EBOV were used as targets. The dynamic range of the assay,more » the inactivation of virus, and specimen stability were also evaluated. The lower limit of detection (LoD) for the assay using inactivated virus was estimated to be 73 copies/mL (95% CI: 51–97 copies/mL). The LoD for infectious virus was estimated to be 1 plaque-forming unit/mL, and for RNA to be 232 copies/mL (95% CI 163–302 copies/mL). The assay correctly identified five different Ebola viruses, Yambuku-Mayinga, Makona-C07, Yambuku-Ecran, Gabon-Ilembe, and Kikwit-956210, and correctly excluded all non-EBOV isolates tested. The conditions used by Xpert® Ebola for inactivation of infectious virus reduced EBOV titer by ≥6 logs. In conclusion, we found the Xpert® Ebola Assay to have high analytical sensitivity and specificity for the detection of EBOV in whole blood. It offers ease of use, fast turnaround time, and remote monitoring. The test has an efficient viral inactivation protocol, fulfills inclusivity and exclusivity criteria, and has specimen stability characteristics consistent with the need for decentralized testing. The simplicity of the assay should enable testing in a wide variety of laboratory settings, including remote laboratories that are not capable of performing highly complex nucleic acid amplification tests, and during outbreaks where time to detection is critical.« less

Analytical Performance Characteristics of the Cepheid GeneXpert Ebola Assay for the Detection of Ebola Virus

DOE PAGES

Pinsky, Benjamin A.; Sahoo, Malaya K.; Sandlund, Johanna; ...

2015-11-12

The recently developed Xpert® Ebola Assay is a novel nucleic acid amplification test for simplified detection of Ebola virus (EBOV) in whole blood and buccal swab samples. The assay targets sequences in two EBOV genes, lowering the risk for new variants to escape detection in the test. The objective of this report is to present analytical characteristics of the Xpert® Ebola Assay on whole blood samples. Our study evaluated the assay’s analytical sensitivity, analytical specificity, inclusivity and exclusivity performance in whole blood specimens. EBOV RNA, inactivated EBOV, and infectious EBOV were used as targets. The dynamic range of the assay,more » the inactivation of virus, and specimen stability were also evaluated. The lower limit of detection (LoD) for the assay using inactivated virus was estimated to be 73 copies/mL (95% CI: 51–97 copies/mL). The LoD for infectious virus was estimated to be 1 plaque-forming unit/mL, and for RNA to be 232 copies/mL (95% CI 163–302 copies/mL). The assay correctly identified five different Ebola viruses, Yambuku-Mayinga, Makona-C07, Yambuku-Ecran, Gabon-Ilembe, and Kikwit-956210, and correctly excluded all non-EBOV isolates tested. The conditions used by Xpert® Ebola for inactivation of infectious virus reduced EBOV titer by ≥6 logs. In conclusion, we found the Xpert® Ebola Assay to have high analytical sensitivity and specificity for the detection of EBOV in whole blood. It offers ease of use, fast turnaround time, and remote monitoring. The test has an efficient viral inactivation protocol, fulfills inclusivity and exclusivity criteria, and has specimen stability characteristics consistent with the need for decentralized testing. The simplicity of the assay should enable testing in a wide variety of laboratory settings, including remote laboratories that are not capable of performing highly complex nucleic acid amplification tests, and during outbreaks where time to detection is critical.« less

Tests for the measurement of factor VII-activating protease (FSAP) activity and antigen levels in citrated plasma, their correlation to PCR testing, and utility for the detection of the Marburg I-polymorphism of FSAP.

PubMed

Stephan, Sina; Schwarz, Herbert; Borchert, Anja; Bussfeld, Delia; Quak, Elfriede; Simshaeuser-Knaub, Beate; Teigelkamp, Stefan; Behrens, Fritz; Vitzthum, Frank

2008-01-01

The single nucleotide Marburg I (MRI) polymorphism of the factor VII-activating protease (FSAP) gene, the prourokinase-activating activity of FSAP, and antigen levels of FSAP in plasma have been associated with incidence and progression of carotid stenosis and venous thromboembolism. However, more information on the extent of these associations, potential further ones, and respective clinical utilities remain to be determined. At present, testing is performed mainly by PCR assays based on probes or SYBR Green I. Some studies include testing for antigen levels of total FSAP and its ability to activate prourokinase. To test large cohorts, it is beneficial to rely on assays that are cost-effective, reliable, easy to use, rapid to perform, and that may eventually be automated. In addition, it appears advantageous to use functional tests or tests that determine antigen levels as they may relate more closely to the phenotype than the genotype does. Tests for the measurements of antigen levels of FSAP and its prourokinase-activating activity were improved and performance characteristics assessed. To determine the FSAP genotypes, an amplification created restriction site (ACRS) PCR test was developed. Key performance characteristics of the FSAP activity and antigen tests were as follows: measuring range: 350-1400 mPEU/mL and 1.8-120 ng/mL, total coefficients of variation (CV): 5%-20% and 5%-14%, within-run CV: 4%-11% and 2.3%-12%, and run-to-run CV: 2%-17% and 4.3%-8.3%, respectively. The ratio of the activity and antigen level of FSAP correctly identified the FSAP genotypes of 126 samples tested. The ACRS PCR test is useful for laboratories that do not have the equipment to perform probe or SYBR Green I based real-time PCR. Furthermore, the tests developed for the determination of FSAP activity and antigen levels are convenient for determining clinical correlations, even for large population studies. The ratio of activity and antigen level of FSAP appears to be a promising and efficient alternative to molecular diagnostic techniques to detect the MRI polymorphism of FSAP.

Contamination avoidance devices for poppet type shutoff valves

NASA Technical Reports Server (NTRS)

Endicott, D. L.

1972-01-01

The technology required to provide acceptable contamination damage avoidance characteristics for poppet type shutoff valves is discussed. Evaluation of the contamination avoidance characteristics of the basic 1T32095 propellant shutoff valve, the cycle life performance of these valves in an uncontaminated environment, and the effectiveness of various auxiliary contamination avoidance devices when used in conjunction with these poppet type valves are included. In addition, a secondary objective is to evaluate two methods of monitoring the performance of the test valves during actual operations using acoustical monitoring instrumentation.

APSA - A new generation of photovoltaic solar arrays

NASA Technical Reports Server (NTRS)

Stella, P. M.; Kurland, R. M.

1989-01-01

This paper provides details on the Advanced Photovoltaic Solar Array (APSA) wing design, fabrication, and testing. The impact of array size change on performance and mechanical characteristics is discussed. Projections for future performance enhancements that may be expected through the use of advanced solar cells presently under development are examined.

FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS. VOLUME I. DISTRIBUTED MIXING BURNER EVALUATION

EPA Science Inventory

The report gives results of a study in which NOx emissions and general combustion performance characteristics of four burners were evaluated under experimental furnace conditions. Of primary interest was the performance of a low NOx Distributed Mixing Burner (DMB), which was test...

Impact performance of two bamboo-based laminated composites

Treesearch

Huanrong Liu; Zehui Jiang; Zhengjun Sun; Yan Yan; Zhiyong Cai; Xiubiao Zhang

2017-01-01

The present work aims to determine the impact performance of two bamboo-based laminated composites [bamboo/poplar laminated composite (BPLC) and bamboo/ glass fiber laminated composite (BGFLC)] using lowvelocity impact tests by a drop tower. In addition, fracture characteristics were evaluated using computed tomography (CT). Results showed that BPLC presented better...

Learning Molecular Structures in a Tangible Augmented Reality Environment

ERIC Educational Resources Information Center

Asai, Kikuo; Takase, Norio

2011-01-01

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

Evaluation of long-term pavement performance and noise characteristics of the next generation concrete surface : final report.

DOT National Transportation Integrated Search

2014-01-01

This report documents the performance of the first Next Generation Concrete Surface (NGCS) built by the : Washington State Department of Transportation (WSDOT). A 1,500 foot test section was installed on the : eastbound lanes of I-82 near Sunnyside, ...

Hover and forward flight acoustics and performance of a small-scale helicopter rotor system

NASA Technical Reports Server (NTRS)

Kitaplioglu, C.; Shinoda, P.

1985-01-01

A 2.1-m diam., 1/6-scale model helicopter main rotor was tested in hover in the test section of the NASA Ames 40- by 80- Foot Wind Tunnel. Subsequently, it was tested in forward flight in the Ames 7- by 10-Foot Wind Tunnel. The primary objective of the tests was to obtain performance and noise data on a small-scale rotor at various thrust coefficients, tip Mach numbers, and, in the later case, various advance ratios, for comparisons with similar existing data on full-scale helicopter rotors. This comparison yielded a preliminary evaluation of the scaling of helicopter rotor performance and acoustic radiation in hover and in forward flight. Correlation between model-scale and full-scale performance and acoustics was quite good in hover. In forward flight, however, there were significant differences in both performance and acoustic characteristics. A secondary objective was to contribute to a data base that will permit the estimation of facility effects on acoustic testing.

Serological tests fail to discriminate dogs with visceral leishmaniasis that transmit Leishmania infantum to the vector Lutzomyia longipalpis.

PubMed

Mendonça, Ivete Lopes de; Batista, Joilson Ferreira; Werneck, Guilherme Loureiro; Soares, Maria Regiane Araújo; Costa, Dorcas Lamounier; Costa, Carlos Henrique Nery

2017-01-01

The control of reservoirs for Leishmania infantum -induced zoonotic visceral leishmaniasis requires the identification of dogs posing a population risk. Here, we assessed the performance of several assays to identify Lutzomyia longipalpis infectious dogs. We evaluated 99 dogs that were positive for visceral leishmaniasis based on parasite identification. Serological analyses were performed using an enzyme-linked immunosorbent assay, immunofluorescence antibody tests in 1:40 and 1:80 dilutions, rapid dual path platform tests, immunochromatographic assay with a recombinant rK39 antigen, fast agglutination screening tests, and direct agglutination tests. We also performed PCR to analyze peripheral blood and xenodiagnosis. Forty-six dogs infected at least one L. longipalpis specimen. Although the serological test sensitivities were above 85% for detecting L. longipalpis infectious dogs, none showed a satisfactory performance, as both specificity (0.06 to 13%) and the area under the receiver operating characteristic curve (45 to 53%) were low. The PCR results were also weak, with a sensitivity of 30%, specificity of 72%, and an area under the receiver operating characteristic curve of 51%. The infected L. longipalpis proportion was higher among asymptomatic dogs than symptomatic dogs. Among the symptomatic dogs, those with ulceration-free skin diseases were more infectious, with an odds ratio of 9.3 (confidence interval of 1.10 - 428.5). The larger the number of insects fed, the greater the detected infectiousness. Our study supports the imperative to develop novel technologies for identifying the infectious dogs that transmit L. infantum for the benefit of public health.

Toward earlier detection of choroidal neovascularization secondary to age-related macular degeneration: multicenter evaluation of a preferential hyperacuity perimeter designed as a home device.

PubMed

Loewenstein, Anat; Ferencz, Joseph R; Lang, Yaron; Yeshurun, Itamar; Pollack, Ayala; Siegal, Ruth; Lifshitz, Tova; Karp, Joseph; Roth, Daniel; Bronner, Guri; Brown, Justin; Mansour, Sam; Friedman, Scott; Michels, Mark; Johnston, Richards; Rapp, Moshe; Havilio, Moshe; Rafaeli, Omer; Manor, Yair

2010-01-01

The primary purpose of this study was to evaluate the ability of a home device preferential hyperacuity perimeter to discriminate between patients with choroidal neovascularization (CNV) and intermediate age-related macular degeneration (AMD), and the secondary purpose was to investigate the dependence of sensitivity on lesion characteristics. All participants were tested with the home device in an unsupervised mode. The first part of this work was retrospective using tests performed by patients with intermediate AMD and newly diagnosed CNV. In the second part, the classifier was prospectively challenged with tests performed by patients with intermediate AMD and newly diagnosed CNV. The dependence of sensitivity on lesion characteristics was estimated with tests performed by patients with CNV of both parts. In 66 eyes with CNV and 65 eyes with intermediate AMD, both sensitivity and specificity were 0.85. In the retrospective part (34 CNV and 43 intermediate AMD), sensitivity and specificity were 0.85 +/- 0.12 (95% confidence interval) and 0.84 +/- 0.11 (95% confidence interval), respectively. In the prospective part (32 CNV and 22 intermediate AMD), sensitivity and specificity were 0.84 +/- 0.13 (95% confidence interval) and 0.86 +/- 0.14 (95% confidence interval), respectively. Chi-square analysis showed no dependence of sensitivity on type (P = 0.44), location (P = 0.243), or size (P = 0.73) of the CNV lesions. A home device preferential hyperacuity perimeter has good sensitivity and specificity in discriminating between patients with newly diagnosed CNV and intermediate AMD. Sensitivity is not dependent on lesion characteristics.

Physical Performance in Elite Male and Female Team Handball Players.

PubMed

Wagner, Herbert; Fuchs, Patrick; Fusco, Andrea; Fuchs, Philip; Bell, W Jeffrey; Duvillard, Serge P

2018-06-12

Biological differences between men and women are well known; however, literature-addressing knowledge about the influence of sex to specific and general performance in team handball is almost nonexistent. Consequently, the aim of the study was to assess and compare specific and general physical performance in male and female elite team handball players, to determine if the differences are consequential for general compared to specific physical performance characteristics and the relationship between general and specific physical performance. Twelve male and ten female elite team handball players performed a game based performance test, upper- und lower-body strength and power tests, a sprinting test, and an incremental treadmill-running test. Significant differences (P<.05) between male and female players were found for peak oxygen uptake and total running time during the treadmill test, 30m sprinting time, leg extension strength, trunk and shoulder rotation torque, counter movement jump height as well as offense and defense time, ball velocity and jump height in the game based performance test. An interaction (sex × test) was found for time and oxygen uptake and except shoulder rotation torque and ball velocity in females, we found only a low relationship between specific and general physical performance. The results of the study revealed that male players are heavier, taller, faster, stronger, jump higher and have a better aerobic performance. However, female players performed relatively better in the team handball specific tests compared to the general tests. Our findings also suggest that female players should focus more on strength training.

Technical and investigative support for high density digital satellite recording systems

NASA Technical Reports Server (NTRS)

Schultz, R. A.

1982-01-01

Methods and results of examinations and tests conducted on magnetic recording tapes under consideration for a high density digital (HDDR) satellite recording system are described. The examinations and tests investigate the performance of tapes with respect to their physical, magnetic and electrical characteristics. The objective of the tests, the likely significance of typical results, and the importance of the characteristics under investigation to the application are included. Theoretical discussions of measurement methods are provided where appropriate. Methods and results are discussed; the results of some sections are tabulated together to facilitate their comparison. The conclusion of each test section relates the test results to their possible significance and attempts to correlate the results of that section with the results of other tests. Some of the sections analyze sources of error inherent in the measurement methods or relate the value of the information obtained to the objectives of the test or the overall purpose of the project.

Pendulum Swings in Educational Policymaking: The Effects of Organizational, School, Financial and Social Characteristics on Student Performance Outcomes in Michigan School Districts

ERIC Educational Resources Information Center

Dyson, Dana D.

2009-01-01

Reforms in American public education have not resolved the wide academic performance gap between students attending schools in poor, large, urban centers versus schools in wealthier areas. Aggregate performance outcomes on state achievement tests reveal that some school districts consistently outperform others, a few fluctuate over time but are…

A Theoretical Analysis of the Performance of Learning Disabled Students on the Woodcock-Johnson Psycho-Educational Battery.

ERIC Educational Resources Information Center

Shinn, Mark; And Others

Two studies were conducted to (1) analyze the subtest characteristics of the Woodcock-Johnson Psycho-Educational Battery, and (2) apply those results to an analysis of 50 fourth grade learning disabled (LD) students' performance on the Battery. Analyses indicated that the poorer performance of LD students on the Woodcock-Johnson Tests of Cognitive…

The Influence of Properties of the Test and Their Interactions with Reader Characteristics on Reading Comprehension: An Explanatory Item Response Study

ERIC Educational Resources Information Center

Kulesz, Paulina A.; Francis, David J.; Barnes, Marcia A.; Fletcher, Jack M.

2016-01-01

Component skills and discourse frameworks of reading have identified characteristics of readers and texts that influence comprehension. However, these 2 frameworks have not previously been integrated in a comprehensive and systematic way to explain performance on any standardized assessment of reading comprehension that is in widespread use across…

Accuracy and Variability of Item Parameter Estimates from Marginal Maximum a Posteriori Estimation and Bayesian Inference via Gibbs Samplers

ERIC Educational Resources Information Center

Wu, Yi-Fang

2015-01-01

Item response theory (IRT) uses a family of statistical models for estimating stable characteristics of items and examinees and defining how these characteristics interact in describing item and test performance. With a focus on the three-parameter logistic IRT (Birnbaum, 1968; Lord, 1980) model, the current study examines the accuracy and…

Pooled effect of injection pressure and turbulence inducer piston on performance, combustion, and emission characteristics of a DI diesel engine powered with biodiesel blend.

PubMed

Isaac JoshuaRamesh Lalvani, J; Parthasarathy, M; Dhinesh, B; Annamalai, K

2016-12-01

In this study, the effect of injection pressure on combustion, performance, and emission characteristics of a diesel engine powered with turbulence inducer piston was studied. Engine tests were executed using conventional diesel and 20% blend of adelfa biodiesel [A20]. The results acquired from renewable fuel A20 in the conventional engine showed reduction in brake thermal efficiency being the result of poor air fuel mixing characteristics and the higher viscosity of the tested fuel. This prompted further research aiming at the improvement of turbulence for better air fuel mixing by a novel turbulence inducer piston [TIP]. The investigation was carried out to study the combined effect of injection pressure and turbulence inducer piston. Considerable improvement in the emission characteristics like hydrocarbon, carbon monoxide, smoke was acheived as a result of optimised injection pressure. Nevertheless, the nitrogen oxide emissions were slightly higher than those of the conventional unmodified engine. The engine with turbulence inducer piston shows the scope for reducing the major pollution and thus ensures environmental safety. Copyright © 2015 Elsevier Inc. All rights reserved.

Ultraviolet radiation-blocking characteristics of contact lenses: relevance to eye protection for psoralen-sensitised patients.

PubMed

Anstey, A; Taylor, D; Chalmers, I; Ansari, E

1999-10-01

Nine brands of contact lens marketed as "UV protective" were tested for ultraviolet (UV) transmission in order to assess potential suitability for psoralen-sensitised patients. UV-transmission characteristics of hydrated lenses was tested with a Bentham monochromator spectro-radiometer system. All lenses showed minimal transmission loss in the visible band. The performance of the nine lenses was uniform for ultraviolet B radiation with negligible transmission, but showed variation in transmission for ultraviolet A radiation. None of the lenses complied with UV-transmission criteria used previously to assess UV-blocking spectacles. Only two lenses had UV-blocking characteristics which came close to the arbitrary criteria used. The performance of ordinary soft and hard lenses was very similar, with negligible blocking of UV radiation. None of the nine contact lenses marketed as "UV protective" excluded sufficient UVA to comply with criteria in current use to assess UV protection in spectacles for psoralen-sensitised patients. However, the improved UV-blocking characteristics of contact lenses identified in this paper compared to previous studies suggests that such a contact lens will soon become available. Meanwhile, contact lens-wearing systemically sensitised PUVA patients should continue to wear approved spectacles for eye protection whilst photosensitised with psoralen.

Multi-center evaluation of the cobas® Liat® Influenza A/B & RSV assay for rapid point of care diagnosis.

PubMed

Gibson, Jane; Schechter-Perkins, Elissa M; Mitchell, Patricia; Mace, Sharon; Tian, Yu; Williams, Kemi; Luo, Robert; Yen-Lieberman, Belinda

2017-10-01

Point of Care Testing (POCT) provides the capability for rapid laboratory test results in patient care environments where a traditional clinical laboratory is not available. POCTs have shorter turn-around times (TATs), they may be performed by non-laboratory personnel, and the need for transport time is eliminated. The Food and Drug Administration (FDA) recently granted Clinical Laboratory Improvements Amendment (CLIA) waiver status to the cobas ® Influenza A/B & RSV assay, a rapid, accurate point-of-care test for Influenza and respiratory syncytial virus (RSV) performed on the Liat ® System. The performance characteristics of this test were determined though a multi-site study consisting of different point of care testing environments. Prospectively collected Nasopharyngeal (NP) swabs from 1361 patients seen at 8 primary care clinics and 4 emergency departments (EDs) and 295 retrospectively identified specimens were tested for Influenza A/B and RSV on the cobas ® Liat ® platform. Performance characteristics were determined through comparison to ProFlu+, a laboratory-based PCR test for Influenza A/B and RSV (reference test). Discordant specimens were adjudicated following bi-directional sequencing. The cobas ® Influenza A/B and RSV assay showed sensitivities of 99.6%, 99.3%, and 96.8% for Influenza A, Influenza B, and RSV, respectively as determined from percent positive agreement (PPA) following comparison to the reference test. Sequencing confirmed cobas ® Influenza A/B and RSV results in 49.2% of reference test discordant specimens, while crossing threshold data suggest increased sensitivity compared to the reference test. The cobas ® Influenza A/B and RSV assay was found to be a rapid, sensitive POCT for the detection of these viruses, and provides laboratory-quality PCR-based diagnostic results in point of care settings. Copyright © 2017 Elsevier B.V. All rights reserved.

Testing and performance characteristics of a 1-kW free piston Stirling engine

NASA Technical Reports Server (NTRS)

Schreiber, J.

1983-01-01

A 1 kW single cylinder free piston Stirling engine, configured as a research engine, was tested with helium working gas. The engine features a posted displacer and dashpot load. The test results show the engine power output and efficiency to be lower than those observed during acceptance tests by the manufacturer. Engine tests results are presented for operation at the two heater head temperatures and with two regenerator porosities, along with flow test results for the heat exchangers.

Dynamic and Transient Performance of Turbofan/Turboshaft Convertible Engine With Variable Inlet Guide Vanes

NASA Technical Reports Server (NTRS)

McArdle, Jack G.; Barth, Richard L.; Wenzel, Leon M.; Biesiadny, Thomas J.

1996-01-01

A convertible engine called the CEST TF34, using the variable inlet guide vane method of power change, was tested on an outdoor stand at the NASA Lewis Research Center with a waterbrake dynamometer for the shaft load. A new digital electronic system, in conjunction with a modified standard TF34 hydromechanical fuel control, kept engine operation stable and safely within limits. All planned testing was completed successfully. Steady-state performance and acoustic characteristics were reported previously and are referenced. This report presents results of transient and dynamic tests. The transient tests measured engine response to several rapid changes in thrust and torque commands at constant fan (shaft) speed. Limited results from dynamic tests using the pseudorandom binary noise technique are also presented. Performance of the waterbrake dynamometer is discussed in an appendix.

Comparison of Test Stand and Helicopter Oil Cooler Bearing Condition Indicators

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.; Branning, Jeremy; Wade, Damiel R.; Bolander, Nathan

2010-01-01

The focus of this paper was to compare the performance of HUMS condition indicators (CI) when detecting a bearing fault in a test stand or on a helicopter. This study compared data from two sources: first, CI data collected from accelerometers installed on two UH-60 Black Hawk helicopters when oil cooler bearing faults occurred, along with data from helicopters with no bearing faults; and second, CI data that was collected from ten cooler bearings, healthy and faulted, that were removed from fielded helicopters and installed in a test stand. A method using Receiver Operating Characteristic (ROC) curves to compare CI performance was demonstrated. Results indicated the bearing energy CI responded differently for the helicopter and the test stand. Future research is required if test stand data is to be used validate condition indicator performance on a helicopter.

The effect of lizardite surface characteristics on pyrite flotation

NASA Astrophysics Data System (ADS)

Feng, Bo; Feng, Qiming; Lu, Yiping

2012-10-01

The effect of lizardite surface characteristics on pyrite flotation has been investigated through flotation tests, adsorption tests, zeta potential measurements, FTIR study, X-ray photoelectron spectroscopy (XPS) and sedimentation tests. The flotation results show that at pH value 9, where flotation of nickel sulfide ores is routinely performed, two kinds of lizardite samples (native lizardite and leached lizardite) have different effects on the flotation of pyrite. The native lizardite adheres to the surface of pyrite and reduces pyrite flotation recovery while the leached lizardite does not interfere with pyrite flotation. Infrared analyses and XPS tests illustrate that acid leaching changed the surface characteristics of lizardite mineral and the leached lizardite has less magnesium on its surface. It has been determined that the electro-kinetic behavior of lizardite aqueous suspensions is mainly a function of the Mg/Si atomic ratio on lizardite surface. So, the low isoelectric point observed in the leached sample has been linked to values of this ratio lower than that of the native lizardite.

ISO 15859 Propellant and Fluid Specifications: A Review and Comparison with Military and NASA Specifications

NASA Technical Reports Server (NTRS)

Greene, Ben; McClure, Mark B.; Baker, David L.

2006-01-01

This work presents an overview of the International Organization for Standardization (ISO) 15859 International Standard for Space Systems Fluid Characteristics, Sampling and Test Methods Parts 1 through 13 issued in June 2004. These standards establish requirements for fluid characteristics, sampling, and test methods for 13 fluids of concern to the propellant community and propellant characterization laboratories: oxygen, hydrogen, nitrogen, helium, nitrogen tetroxide, monomethylhydrazine, hydrazine, kerosene, argon, water, ammonia, carbon dioxide, and breathing air. A comparison of the fluid characteristics, sampling, and test methods required by the ISO standards to the current military and NASA specifications, which are in use at NASA facilities and elsewhere, is presented. Many ISO standards composition limits and other content agree with those found in the applicable parts of NASA SE-S-0073, NASA SSP 30573, military performance standards and details, and Compressed Gas Association (CGA) commodity specifications. The status of a current project managed at NASA Johnson Space Center White Sands Test Facility (WSTF) to rewrite these documents is discussed.

Solid state high resolution multi-spectral imager CCD test phase

NASA Technical Reports Server (NTRS)

1973-01-01

The program consisted of measuring the performance characteristics of charge coupled linear imaging devices, and a study defining a multispectral imaging system employing advanced solid state photodetection techniques.

A randomized comparison of laparoscopic, magnetically anchored, and flexible endoscopic cameras in performance and workload between laparoscopic and single-incision surgery.

PubMed

Arain, Nabeel A; Cadeddu, Jeffrey A; Best, Sara L; Roshek, Thomas; Chang, Victoria; Hogg, Deborah C; Bergs, Richard; Fernandez, Raul; Webb, Erin M; Scott, Daniel J

2012-04-01

This study aimed to evaluate the surgeon performance and workload of a next-generation magnetically anchored camera compared with laparoscopic and flexible endoscopic imaging systems for laparoscopic and single-site laparoscopy (SSL) settings. The cameras included a 5-mm 30° laparoscope (LAP), a magnetically anchored (MAGS) camera, and a flexible endoscope (ENDO). The three camera systems were evaluated using standardized optical characteristic tests. Each system was used in random order for visualization during performance of a standardized suturing task by four surgeons. Each participant performed three to five consecutive repetitions as a surgeon and also served as a camera driver for other surgeons. Ex vivo testing was conducted in a laparoscopic multiport and SSL layout using a box trainer. In vivo testing was performed only in the multiport configuration and used a previously validated live porcine Nissen model. Optical testing showed superior resolution for MAGS at 5 and 10 cm compared with LAP or ENDO. The field of view ranged from 39 to 99°. The depth of focus was almost three times greater for MAGS (6-270 mm) than for LAP (2-88 mm) or ENDO (1-93 mm). Both ex vivo and in vivo multiport combined surgeon performance was significantly better for LAP than for ENDO, but no significant differences were detected for MAGS. For multiport testing, workload ratings were significantly less ex vivo for LAP and MAGS than for ENDO and less in vivo for LAP than for MAGS or ENDO. For ex vivo SSL, no significant performance differences were detected, but camera drivers rated the workload significantly less for MAGS than for LAP or ENDO. The data suggest that the improved imaging element of the next-generation MAGS camera has optical and performance characteristics that meet or exceed those of the LAP or ENDO systems and that the MAGS camera may be especially useful for SSL. Further refinements of the MAGS camera are encouraged.

Factors related to performance effectiveness of dental nurse in primary care unit in the northeastern part of Thailand.

PubMed

Wijaranaphiti, Saowaluk; Krugkrunjit, Peera; Intaraprasong, Bhusita

2009-12-01

To investigate the relationships between job characteristics, motivation, role stress and performance effectiveness of dental nurses in primary care units in the northeastern part of Thailand. A explanatory cross-sectional study was conducted in 326 dental nurses who were working in 310 PCUs of 19 provinces, 220 amphurs in the northeastern part of Thailand were taken as the study samples. Data were collected by using questionnaires. Pearson's Product Moment Correlation was applied to test between job characteristic model, motivation, role stress and performance effectiveness. The analysis showed that there was no relationship between job characteristics model and performance effectiveness as performing dental task needed 'dealing with others' and 'task significance'. There was a positive relationship between motivation and performance effectiveness at a low level. Role stress was not related to performance effectiveness; however, when the dental nurse had more stress caused by role conflict internal standard, several roles and their performance effectiveness was reduced. From the research result, it is necessary to help construct networks of dental tasks and other public health tasks in obvious forms, for some feedback from agents. Work allocation should be precisely arranged and professional skill should be determined responsibility. Lastly, recruiting dental nurses with proper characteristics in primary care units in the northeastern part of Thailand is crucial as well.

How do task characteristics affect learning and performance? The roles of variably mapped and dynamic tasks.

PubMed

Macnamara, Brooke N; Frank, David J

2018-05-01

For well over a century, scientists have investigated individual differences in performance. The majority of studies have focused on either differences in practice, or differences in cognitive resources. However, the predictive ability of either practice or cognitive resources varies considerably across tasks. We are the first to examine task characteristics' impact on learning and performance in a complex task while controlling for other task characteristics. In 2 experiments we test key theoretical task characteristic thought to moderate the relationship between practice, cognitive resources, and performance. We devised a task where each of several key task characteristics can be manipulated independently. Participants played 5 rounds of a game similar to the popular tower defense videogame Plants vs. Zombies where both cognitive load and game characteristics were manipulated. In Experiment 1, participants either played a consistently mapped version-the stimuli and the associated meaning of their properties were constant across the 5 rounds-or played a variably mapped version-the stimuli and the associated meaning of their properties changed every few minutes. In Experiment 2, participants either played a static version-that is, turn taking with no time pressure-or played a dynamic version-that is, the stimuli moved regardless of participants' response rates. In Experiment 1, participants' accuracy and efficiency were substantially hindered in the variably mapped conditions. In Experiment 2, learning and performance accuracy were hindered in the dynamic conditions, especially when under cognitive load. Our results suggest that task characteristics impact the relative importance of cognitive resources and practice on predicting learning and performance. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A static investigation of several STOVL exhaust system concepts

NASA Technical Reports Server (NTRS)

Romine, B. M., Jr.; Meyer, B. E.; Re, R. J.

1989-01-01

A static cold flow scale model test was performed in order to determine the internal performance characteristics of various STOVL exhaust systems. All of the concepts considered included a vectorable cruise nozzle and a separate vectorable vertical thrust ventral nozzle mounted on the tailpipe. The two ventral nozzle configurations tested featured vectorable constant thickness cascade vanes for area control and improved performance during transition and vertical lift flight. The best transition performance was achieved using a butterfly door type ventral nozzle and a pitch vectoring 2DCD or axisymmetric cruise nozzle. The clamshell blocker type of ventral nozzle had reduced transition performance due to the choking of the tailpipe flow upstream of the cruise nozzle.

Wind-tunnel research comparing lateral control devices, particularly at high angles of attack XII : upper-surface ailerons on wings with split flaps

NASA Technical Reports Server (NTRS)

Weick, Fred E; Wenzinger, Carl J

1935-01-01

This report covers the twelfth of a series of tests conducted to compare different lateral control devices with particular reference to their effectiveness at high angles of attack. The present wind tunnel tests were made with two sizes of upper-surface ailerons on rectangular Clark Y wing models equipped with full span split flaps. The tests showed the effect of the upper-surface ailerons and of the split flaps on the general performance characteristics of the wings, and on the lateral controllability and stability characteristics. The results are compared with those for plain wings with ordinary ailerons of similar sizes.

Comparison of Theoretical and Experimental Heat-Transfer Characteristics of Bodies of Revolution at Supersonic Speeds

NASA Technical Reports Server (NTRS)

Scherrer, Richard

1951-01-01

An investigation of the three important factors that determine convective heat-transfer characteristics at supersonic speeds, location boundary-layer transition, recovery factor, and heat-transfer parameter has been performed at Mach numbers from 1.49 to 1.18. The bodies of revolution that were tested had, in most cases, laminar boundary layers, and the test results have been compared with available theory. Boundary-layer transition was found to be affected by heat transfer. Adding heat to a laminar boundary layer caused transition to move forward on the test body, while removing heat caused transition to move rearward. These experimental results and the implications of boundary-layer-stability theory are in qualitative agreement.

Flight test investigation of the vortex wake characteristics behind a Boeing 727 during two-segment and normal ILS approaches (A joint NASA/FAA report)

NASA Technical Reports Server (NTRS)

Barber, M. R.; Kurkowski, R. L.; Garodz, L. J.; Robinson, G. H.; Smith, H. J.; Jacobsen, R. A.; Stinnett, G. W., Jr.; Mcmurtry, T. C.; Tymczyszyn, J. J.; Devereaux, R. L.

1975-01-01

Flight tests were performed to evaluate the vortex wake characteristics of a Boeing 727 aircraft during conventional and two-segment instrument landing approaches. Smoke generators were used for vortex marking. The vortex was intentionally intercepted by a Lear Jet and a Piper Comanche aircraft. The vortex location during landing approach was measured using a system of phototheodolites. The tests showed that at a given separation distance there are no readily apparent differences in the upsets resulting from deliberate vortex encounters during the two types of approaches. The effect of the aircraft configuration on the extent and severity of the vortices is discussed.

Gender Differentiations of Some Anthropological Characteristics of Karate Players--Cadets.

PubMed

Jukić, Josefina

2015-07-01

The research was conducted with the aim of determining gender differentiations of some anthropological characteristics of male and female cadet karate players. To achieve this aim, a group of 10 morphological variables, ten motor tests, five situation motor test and six technical performance evaluation tests was applied. Two hundred and six competing players were measured, of which 105 male and 101 female. The examinees were divided according to weight categories (lower and higher weight categories). Based on the variance analysis and canon discrimination analysis a conclusion can be made: gender differentiations are most strongly expressed in morphological and basic motor area, and significantly less in the area of specific motor abilities and motor knowledge (technical efficiency).

Correlation of the Characteristics of Single-Cylinder and Flight Engines in Tests of High-Performance Fuels in an Air-Cooled Engine I : Cooling Characteristics

NASA Technical Reports Server (NTRS)

Wilson, Robert W.; Richard, Paul H.; Brown, Kenneth D.

1945-01-01

Variable charge-air flow, cooling-air pressure drop, and fuel-air ration investigations were conducted to determine the cooling characteristics of a full-scale air-cooled single cylinder on a CUE setup. The data are compared with similar data that were available for the same model multicylinder engine tested in flight in a four-engine airplane. The cylinder-head cooling correlations were the same for both the single-cylinder and the flight engine. The cooling correlations for the barrels differed slightly in that the barrel of the single-cylinder engine runs cooler than the barrel of te flight engine for the same head temperatures and engine conditions.

Low-speed aerodynamic characteristics of a 13 percent thick medium speed airfoil designed for general aviation applications

NASA Technical Reports Server (NTRS)

Mcghee, R. J.; Beasley, W. D.

1979-01-01

Wind tunnel tests were conducted to determine the low speed, two dimensional aerodynamic characteristics of a 13percent thick medium speed airfoil designed for general aviation applications. The results were compared with data for the 13 percent thick low speed airfoil. The tests were conducted over a Mach number range from 0.10 to 0.32, a chord Reynolds number range from 2.0 x 10 to the 6th power to 12.0 x 10 to the 6th power, and an angle of attack frange from about -8 deg to 10 deg. The objective of retaining good high-lift low speed characteristics for an airfoil designed to have good medium speed cruise performance was achieved.

[Correlation between demyelinating lesions and executive function decline in a sample of Mexican patients with multiple sclerosis].

PubMed

Aldrete Cortez, V R; Duriez-Sotelo, E; Carrillo-Mora, P; Pérez-Zuno, J A

2013-09-01

Multiple Sclerosis (MS) is characterised by several neurological symptoms including cognitive impairment, which has recently been the subject of considerable study. At present, evidence pointing to a correlation between lesion characteristics and specific cognitive impairment is not conclusive. To investigate the presence of a correlation between the characteristics of demyelinating lesions and performance of basic executive functions in a sample of MS patients. We included 21 adult patients with scores of 0 to 5 on the Kurtzke scale and no exacerbations of the disease in at least 3 months prior to the evaluation date. They completed the Stroop test and the Wisconsin Card Sorting Test (WCST). The location of the lesions was determined using magnetic resonance imaging (MRI) performed by a blinded expert in neuroimaging. Demyelinating lesions were more frequently located in the frontal and occipital lobes. The Stroop test showed that as cognitive demand increased on each of the sections in the test, reaction time and number of errors increased. On the WCST, 33.33% of patients registered as having moderate cognitive impairment. No correlation could be found between demyelinating lesion characteristics (location, size, and number) and patients' scores on the tests. Explanations of the causes of cognitive impairment in MS should examine a variety of biological, psychological, and social factors instead of focusing solely on demyelinating lesions. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Testing of lift/cruise fan exhaust deflector. [for a tip turbine lift fan in short takeoff aircraft

NASA Technical Reports Server (NTRS)

Schlundt, D. W.

1975-01-01

A lift/cruise exhaust deflector system for the LF336/A tip turbine lift fan was designed, built, and tested to determine the design and performance characteristics of a large-scale, single swivel nozzle thrust vectoring system. The exhaust deflector static testing was performed at the Ames Research Center outside static test stand facilities. The test hardware was installed on a hydraulic lift platform to permit both in and out of ground effect testing. The exhaust flow of the LF336/A lift fan was vectored from 0 degrees through 130 degrees during selected fan speeds to obtain performance at different operating conditions. The system was operated with and without flow vanes installed in the small radius bends to evaluate the system performance based on a proposed method of improving the internal flow losses. The program also included testing at different ground heights, to the nozzle exhaust plane, to obtain ground effect data, and the testing of two methods of thrust spoiling using a duct bypass door system and nozzle flap system.

Verification of performance specifications of a molecular test: cystic fibrosis carrier testing using the Luminex liquid bead array.

PubMed

Lacbawan, Felicitas L; Weck, Karen E; Kant, Jeffrey A; Feldman, Gerald L; Schrijver, Iris

2012-01-01

The number of clinical laboratories introducing various molecular tests to their existing test menu is continuously increasing. Prior to offering a US Food and Drug Administration-approved test, it is necessary that performance characteristics of the test, as claimed by the company, are verified before the assay is implemented in a clinical laboratory. To provide an example of the verification of a specific qualitative in vitro diagnostic test: cystic fibrosis carrier testing using the Luminex liquid bead array (Luminex Molecular Diagnostics, Inc, Toronto, Ontario). The approach used by an individual laboratory for verification of a US Food and Drug Administration-approved assay is described. Specific verification data are provided to highlight the stepwise verification approach undertaken by a clinical diagnostic laboratory. Protocols for verification of in vitro diagnostic assays may vary between laboratories. However, all laboratories must verify several specific performance specifications prior to implementation of such assays for clinical use. We provide an example of an approach used for verifying performance of an assay for cystic fibrosis carrier screening.