40 CFR 63.7515 - When must I conduct subsequent performance tests or fuel analyses?
Code of Federal Regulations, 2010 CFR
2010-07-01
... performance tests or fuel analyses? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL PROTECTION... Requirements § 63.7515 When must I conduct subsequent performance tests or fuel analyses? (a) You must conduct... previous performance test. (f) You must conduct a fuel analysis according to § 63.7521 for each type of...
40 CFR 63.7515 - When must I conduct subsequent performance tests or fuel analyses?
Code of Federal Regulations, 2011 CFR
2011-07-01
... performance tests or fuel analyses? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL PROTECTION... Requirements § 63.7515 When must I conduct subsequent performance tests or fuel analyses? (a) You must conduct... previous performance test. (f) You must conduct a fuel analysis according to § 63.7521 for each type of...
40 CFR 63.7515 - When must I conduct subsequent performance tests or fuel analyses?
Code of Federal Regulations, 2012 CFR
2012-07-01
... performance tests or fuel analyses? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL PROTECTION... Requirements § 63.7515 When must I conduct subsequent performance tests or fuel analyses? (a) You must conduct... previous performance test. (f) You must conduct a fuel analysis according to § 63.7521 for each type of...
40 CFR 63.7515 - When must I conduct subsequent performance tests, fuel analyses, or tune-ups?
Code of Federal Regulations, 2014 CFR
2014-07-01
... performance tests, fuel analyses, or tune-ups? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL..., fuel analyses, or tune-ups? (a) You must conduct all applicable performance tests according to § 63... performance tests and the associated fuel analyses within 60 days after the completion of the performance...
40 CFR 63.7515 - When must I conduct subsequent performance tests, fuel analyses, or tune-ups?
Code of Federal Regulations, 2013 CFR
2013-07-01
... performance tests, fuel analyses, or tune-ups? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL..., fuel analyses, or tune-ups? (a) You must conduct all applicable performance tests according to § 63... performance tests and the associated fuel analyses within 60 days after the completion of the performance...
40 CFR 63.7515 - When must I conduct subsequent performance tests, fuel analyses, or tune-ups?
Code of Federal Regulations, 2011 CFR
2011-07-01
... performance tests, fuel analyses, or tune-ups? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL... Compliance Requirements § 63.7515 When must I conduct subsequent performance tests, fuel analyses, or tune... and the associated initial fuel analyses within 90 days after the completion of the performance tests...
40 CFR 63.7515 - When must I conduct subsequent performance tests, fuel analyses, or tune-ups?
Code of Federal Regulations, 2012 CFR
2012-07-01
... performance tests, fuel analyses, or tune-ups? 63.7515 Section 63.7515 Protection of Environment ENVIRONMENTAL... Compliance Requirements § 63.7515 When must I conduct subsequent performance tests, fuel analyses, or tune... and the associated initial fuel analyses within 90 days after the completion of the performance tests...
40 CFR 63.11220 - When must I conduct subsequent performance tests or fuel analyses?
Code of Federal Regulations, 2014 CFR
2014-07-01
... performance tests or fuel analyses? 63.11220 Section 63.11220 Protection of Environment ENVIRONMENTAL... When must I conduct subsequent performance tests or fuel analyses? (a) If your boiler has a heat input... performance (stack) tests according to § 63.11212 on a triennial basis, except as specified in paragraphs (b...
40 CFR 63.11220 - When must I conduct subsequent performance tests or fuel analyses?
Code of Federal Regulations, 2013 CFR
2013-07-01
... performance tests or fuel analyses? 63.11220 Section 63.11220 Protection of Environment ENVIRONMENTAL... When must I conduct subsequent performance tests or fuel analyses? (a) If your boiler has a heat input... performance (stack) tests according to § 63.11212 on a triennial basis, except as specified in paragraphs (b...
The Validity of Conscientiousness Is Overestimated in the Prediction of Job Performance.
Kepes, Sven; McDaniel, Michael A
2015-01-01
Sensitivity analyses refer to investigations of the degree to which the results of a meta-analysis remain stable when conditions of the data or the analysis change. To the extent that results remain stable, one can refer to them as robust. Sensitivity analyses are rarely conducted in the organizational science literature. Despite conscientiousness being a valued predictor in employment selection, sensitivity analyses have not been conducted with respect to meta-analytic estimates of the correlation (i.e., validity) between conscientiousness and job performance. To address this deficiency, we reanalyzed the largest collection of conscientiousness validity data in the personnel selection literature and conducted a variety of sensitivity analyses. Publication bias analyses demonstrated that the validity of conscientiousness is moderately overestimated (by around 30%; a correlation difference of about .06). The misestimation of the validity appears to be due primarily to suppression of small effects sizes in the journal literature. These inflated validity estimates result in an overestimate of the dollar utility of personnel selection by millions of dollars and should be of considerable concern for organizations. The fields of management and applied psychology seldom conduct sensitivity analyses. Through the use of sensitivity analyses, this paper documents that the existing literature overestimates the validity of conscientiousness in the prediction of job performance. Our data show that effect sizes from journal articles are largely responsible for this overestimation.
The Validity of Conscientiousness Is Overestimated in the Prediction of Job Performance
2015-01-01
Introduction Sensitivity analyses refer to investigations of the degree to which the results of a meta-analysis remain stable when conditions of the data or the analysis change. To the extent that results remain stable, one can refer to them as robust. Sensitivity analyses are rarely conducted in the organizational science literature. Despite conscientiousness being a valued predictor in employment selection, sensitivity analyses have not been conducted with respect to meta-analytic estimates of the correlation (i.e., validity) between conscientiousness and job performance. Methods To address this deficiency, we reanalyzed the largest collection of conscientiousness validity data in the personnel selection literature and conducted a variety of sensitivity analyses. Results Publication bias analyses demonstrated that the validity of conscientiousness is moderately overestimated (by around 30%; a correlation difference of about .06). The misestimation of the validity appears to be due primarily to suppression of small effects sizes in the journal literature. These inflated validity estimates result in an overestimate of the dollar utility of personnel selection by millions of dollars and should be of considerable concern for organizations. Conclusion The fields of management and applied psychology seldom conduct sensitivity analyses. Through the use of sensitivity analyses, this paper documents that the existing literature overestimates the validity of conscientiousness in the prediction of job performance. Our data show that effect sizes from journal articles are largely responsible for this overestimation. PMID:26517553
Site-Specific Analyses for Demonstrating Compliance with 10 CFR 61 Performance Objectives - 12179
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grossman, C.J.; Esh, D.W.; Yadav, P.
2012-07-01
The U.S. Nuclear Regulatory Commission (NRC) is proposing to amend its regulations at 10 CFR Part 61 to require low-level radioactive waste disposal facilities to conduct site-specific analyses to demonstrate compliance with the performance objectives in Subpart C. The amendments would require licensees to conduct site-specific analyses for protection of the public and inadvertent intruders as well as analyses for long-lived waste. The amendments would ensure protection of public health and safety, while providing flexibility to demonstrate compliance with the performance objectives, for current and potential future waste streams. NRC staff intends to submit proposed rule language and associated regulatorymore » basis to the Commission for its approval in early 2012. The NRC staff also intends to develop associated guidance to accompany any proposed amendments. The guidance is intended to supplement existing low-level radioactive waste guidance on issues pertinent to conducting site-specific analyses to demonstrate compliance with the performance objectives. The guidance will facilitate implementation of the proposed amendments by licensees and assist competent regulatory authorities in reviewing the site-specific analyses. Specifically, the guidance provides staff recommendations on general considerations for the site-specific analyses, modeling issues for assessments to demonstrate compliance with the performance objectives including the performance assessment, intruder assessment, stability assessment, and analyses for long-lived waste. This paper describes the technical basis for changes to the rule language and the proposed guidance associated with implementation of the rule language. The NRC staff, per Commission direction, intends to propose amendments to 10 CFR Part 61 to require licensees to conduct site-specific analyses to demonstrate compliance with performance objectives for the protection of public health and the environment. The amendments would require a performance assessment to demonstrate protection of the general population from releases of radioactivity, an assessment to demonstrate protection of a potential inadvertent intruder, and a long-term analysis to assess how the design of the facility considers the potential radiological impacts associated with disposal of long-lived waste streams. Concurrently, the NRC staff intends to propose associated guidance to facilitate the implementation of the requirements to conduct site-specific analyses. In proposing these amendments to the regulation and associated guidance, the NRC staff has conducted extensive public outreach since 2009 including three public meetings and four briefings of the NRC's Advisory Committee on Reactor Safeguards. The NRC staff plans to submit the proposed amendments to the regulations to the Commission in early 2012. Subsequently, the proposed amendments and associated guidance would be published in the Federal Register for public comment pending approval of the proposed amendments to the regulations by the Commission. Following the public comment period, NRC staff plans to address public comments and revise, as necessary, the regulations and associated guidance before publishing a final rule, which is anticipated in 2013. (authors)« less
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-05
.... This draft document describes the quantitative analyses that are being conducted as part of the review... primary (health-based) CO NAAQS, the Agency is conducting qualitative and quantitative assessments... results, observations, and related uncertainties associated with the quantitative analyses performed. An...
10 CFR 850.40 - Performance feedback.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Performance feedback. (a) The responsible employer must conduct periodic analyses and assessments of... reporting data. (b) To ensure that information is available to maintain and improve all elements of the CBDPP continuously, the responsible employer must give results of periodic analyses and assessments to...
10 CFR 850.40 - Performance feedback.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Performance feedback. (a) The responsible employer must conduct periodic analyses and assessments of... reporting data. (b) To ensure that information is available to maintain and improve all elements of the CBDPP continuously, the responsible employer must give results of periodic analyses and assessments to...
10 CFR 850.40 - Performance feedback.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Performance feedback. (a) The responsible employer must conduct periodic analyses and assessments of... reporting data. (b) To ensure that information is available to maintain and improve all elements of the CBDPP continuously, the responsible employer must give results of periodic analyses and assessments to...
10 CFR 850.40 - Performance feedback.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Performance feedback. (a) The responsible employer must conduct periodic analyses and assessments of... reporting data. (b) To ensure that information is available to maintain and improve all elements of the CBDPP continuously, the responsible employer must give results of periodic analyses and assessments to...
10 CFR 850.40 - Performance feedback.
Code of Federal Regulations, 2013 CFR
2013-01-01
... Performance feedback. (a) The responsible employer must conduct periodic analyses and assessments of... reporting data. (b) To ensure that information is available to maintain and improve all elements of the CBDPP continuously, the responsible employer must give results of periodic analyses and assessments to...
40 CFR 63.11213 - What fuel analyses and procedures must I use for the performance tests?
Code of Federal Regulations, 2013 CFR
2013-07-01
... What fuel analyses and procedures must I use for the performance tests? (a) You must conduct fuel... approximately equal intervals during a test run period. (c) Determine the concentration of mercury in the fuel... 40 Protection of Environment 15 2013-07-01 2013-07-01 false What fuel analyses and procedures must...
40 CFR 63.11213 - What fuel analyses and procedures must I use for the performance tests?
Code of Federal Regulations, 2011 CFR
2011-07-01
... What fuel analyses and procedures must I use for the performance tests? (a) You must conduct fuel... approximately equal intervals during a test run period. (c) Determine the concentration of mercury in the fuel... 40 Protection of Environment 14 2011-07-01 2011-07-01 false What fuel analyses and procedures must...
40 CFR 63.11213 - What fuel analyses and procedures must I use for the performance tests?
Code of Federal Regulations, 2014 CFR
2014-07-01
... What fuel analyses and procedures must I use for the performance tests? (a) You must conduct fuel... approximately equal intervals during a test run period. (c) Determine the concentration of mercury in the fuel... 40 Protection of Environment 15 2014-07-01 2014-07-01 false What fuel analyses and procedures must...
40 CFR 63.11213 - What fuel analyses and procedures must I use for the performance tests?
Code of Federal Regulations, 2012 CFR
2012-07-01
... What fuel analyses and procedures must I use for the performance tests? (a) You must conduct fuel... approximately equal intervals during a test run period. (c) Determine the concentration of mercury in the fuel... 40 Protection of Environment 15 2012-07-01 2012-07-01 false What fuel analyses and procedures must...
Advanced blade tip seal system, volume 2
NASA Technical Reports Server (NTRS)
Zelahy, J. W.; Fairbanks, N. P.
1982-01-01
The results of the endurance and performance engine tests conducted on monocrystal/abrasive-tipped CF6-50 Stage 1 HPT blades fabricated in Task VII of MATE Project 3 are presented. Two engine tests are conducted. The endurance engine test is conducted for 1000 C cycles. The performance engine test is conducted on a variable cycle core engine. Posttest evaluation and analyses of the blades and shrouds included visual, dimensional, and destructive evaluations.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-03
... available under ADAMS accession number ML111040419, and the ``Technical Analysis Supporting Definition of... NUCLEAR REGULATORY COMMISSION 10 CFR Part 61 RIN 3150-AI92 [NRC-2011-0012] Site-Specific Analyses...-level radioactive waste disposal facilities to conduct site-specific analyses to demonstrate compliance...
Damage Tolerance Analysis of a Pressurized Liquid Oxygen Tank
NASA Technical Reports Server (NTRS)
Forth, Scott C.; Harvin, Stephen F.; Gregory, Peyton B.; Mason, Brian H.; Thompson, Joe E.; Hoffman, Eric K.
2006-01-01
A damage tolerance assessment was conducted of an 8,000 gallon pressurized Liquid Oxygen (LOX) tank. The LOX tank is constructed of a stainless steel pressure vessel enclosed by a thermal-insulating vacuum jacket. The vessel is pressurized to 2,250 psi with gaseous nitrogen resulting in both thermal and pressure stresses on the tank wall. Finite element analyses were performed on the tank to characterize the stresses from operation. Engineering material data was found from both the construction of the tank and the technical literature. An initial damage state was assumed based on records of a nondestructive inspection performed on the tank. The damage tolerance analyses were conducted using the NASGRO computer code. This paper contains the assumptions, and justifications, made for the input parameters to the damage tolerance analyses and the results of the damage tolerance analyses with a discussion on the operational safety of the LOX tank.
Network meta-analyses performed by contracting companies and commissioned by industry.
Schuit, Ewoud; Ioannidis, John Pa
2016-11-25
Industry commissions contracting companies to perform network meta-analysis for health technology assessment (HTA) and reimbursement submissions. Our objective was to estimate the number of network meta-analyses performed by consulting companies contracted by industry, to assess whether they were published, and to explore reasons for non-publication. We searched MEDLINE for network meta-analyses of randomized trials. Papers were included if they had authors affiliated with any contracting company. All identified contracting companies as well as additional ones from the list of the exhibitors at the International Society for Pharmacoeconomics and Outcomes Research, an annual meeting that representatives from many contracting companies attend and exhibit at, were surveyed regarding conduct and publication of network meta-analyses. In 162 of 822 (20%) network meta-analysis papers, authors were affiliated to 66 contracting companies. Another 36 contracting companies were identified by the exhibitors list. Three companies had no contact information and six merged with others, therefore 93 companies were contacted. Thirty seven out of ninety three (40%) companies responded, and 19 indicated that they had performed a total of 476 network meta-analyses, but only 102 (21%) papers were published. Thirteen companies that disclosed to have conducted 174 network meta-analyses (45 published) provided reasons for non-publication. Of the 129 still unpublished meta-analyses, for 40 there were plans for future publication, for 37 the sponsor did not allow publication, for 16 the contracting companies did not plan to publish the meta-analysis, for another 23 plans were unclear, and the remaining 13 were used as HTA submission. The protocol of the network meta-analysis was publically available from 11/162 (6.8%) network meta-analyses published by authors affiliated with contracting companies. There is a prolific sector of professional contracting companies that perform network meta-analyses. Industry commissions many network meta-analyses, but most are not registered before or published after analyses in the scientific literature. Mechanisms to improve publication rates of network meta-analysis commissioned by industry are warranted.
77 FR 4556 - Environmental Management Advisory Board
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-30
... activities, cost/ benefit analyses, program performance, human capital development, and contracts and... conduct of the Department's mission and to be in the public interest in connection with the performance of...
Recent evaluations of crack-opening-area in circumferentially cracked pipes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rahman, S.; Brust, F.; Ghadiali, N.
1997-04-01
Leak-before-break (LBB) analyses for circumferentially cracked pipes are currently being conducted in the nuclear industry to justify elimination of pipe whip restraints and jet shields which are present because of the expected dynamic effects from pipe rupture. The application of the LBB methodology frequently requires calculation of leak rates. The leak rates depend on the crack-opening area of the through-wall crack in the pipe. In addition to LBB analyses which assume a hypothetical flaw size, there is also interest in the integrity of actual leaking cracks corresponding to current leakage detection requirements in NRC Regulatory Guide 1.45, or for assessingmore » temporary repair of Class 2 and 3 pipes that have leaks as are being evaluated in ASME Section XI. The objectives of this study were to review, evaluate, and refine current predictive models for performing crack-opening-area analyses of circumferentially cracked pipes. The results from twenty-five full-scale pipe fracture experiments, conducted in the Degraded Piping Program, the International Piping Integrity Research Group Program, and the Short Cracks in Piping and Piping Welds Program, were used to verify the analytical models. Standard statistical analyses were performed to assess used to verify the analytical models. Standard statistical analyses were performed to assess quantitatively the accuracy of the predictive models. The evaluation also involved finite element analyses for determining the crack-opening profile often needed to perform leak-rate calculations.« less
Lim, Kelvin O.; Ardekani, Babak A.; Nierenberg, Jay; Butler, Pamela D.; Javitt, Daniel C.; Hoptman, Matthew J.
2007-01-01
Patients with schizophrenia show deficits in several neurocognitive domains. However, the relationship between white matter integrity and performance in these domains is poorly understood. The authors conducted neurocognitive testing and diffusion tensor imaging in 25 patients with schizophrenia. Performance was examined for tests of verbal declarative memory, attention, and executive function. Relationships between fractional anisotropy and cognitive performance were examined by using voxelwise correlational analyses. In each case, better performance on these tasks was associated with higher levels of fractional anisotropy in task-relevant regions. PMID:17074956
Analyses Relating to Pavement Material Characterizations and Their Effects......
DOT National Transportation Integrated Search
1998-01-01
This report presents the analysis conducted on relating pavement performance or response measures and design considerations to specific pavement layers utilizing data contained in the Long Term Pavement Performance Program National Information Manage...
Guide to reporting highway statistics
DOT National Transportation Integrated Search
1983-11-01
Previous analyses conducted by the Federal Highway Administration (FHWA) are used to project year-by-year economical impacts of changes in highway performance out to 1995. In the principal scenario examined, highway performance is allowed to deterior...
Analysis of spacecraft on-orbit anomalies and lifetimes
NASA Technical Reports Server (NTRS)
Bloomquist, C.; Graham, W.
1983-01-01
Analyses of the on-orbit performance of forty-four unmanned NASA spacecraft are presented. Included are detailed descriptions and classifications of over 600 anomalies; each anomalous incident represents one reported deviation from expected spacecraft performance. Charts depicting satellite lifetimes and the performance of their major subsystems are included. Engineering analyses to further investigate the kinds and frequencies of various classes of anomalies have been conducted. An improved method for charting spacecraft capability as a function of time on orbit is explored.
Rudnick, Paul A.; Clauser, Karl R.; Kilpatrick, Lisa E.; Tchekhovskoi, Dmitrii V.; Neta, Pedatsur; Blonder, Nikša; Billheimer, Dean D.; Blackman, Ronald K.; Bunk, David M.; Cardasis, Helene L.; Ham, Amy-Joan L.; Jaffe, Jacob D.; Kinsinger, Christopher R.; Mesri, Mehdi; Neubert, Thomas A.; Schilling, Birgit; Tabb, David L.; Tegeler, Tony J.; Vega-Montoto, Lorenzo; Variyath, Asokan Mulayath; Wang, Mu; Wang, Pei; Whiteaker, Jeffrey R.; Zimmerman, Lisa J.; Carr, Steven A.; Fisher, Susan J.; Gibson, Bradford W.; Paulovich, Amanda G.; Regnier, Fred E.; Rodriguez, Henry; Spiegelman, Cliff; Tempst, Paul; Liebler, Daniel C.; Stein, Stephen E.
2010-01-01
A major unmet need in LC-MS/MS-based proteomics analyses is a set of tools for quantitative assessment of system performance and evaluation of technical variability. Here we describe 46 system performance metrics for monitoring chromatographic performance, electrospray source stability, MS1 and MS2 signals, dynamic sampling of ions for MS/MS, and peptide identification. Applied to data sets from replicate LC-MS/MS analyses, these metrics displayed consistent, reasonable responses to controlled perturbations. The metrics typically displayed variations less than 10% and thus can reveal even subtle differences in performance of system components. Analyses of data from interlaboratory studies conducted under a common standard operating procedure identified outlier data and provided clues to specific causes. Moreover, interlaboratory variation reflected by the metrics indicates which system components vary the most between laboratories. Application of these metrics enables rational, quantitative quality assessment for proteomics and other LC-MS/MS analytical applications. PMID:19837981
DOT National Transportation Integrated Search
2005-03-16
Non-linear large deformation analyses have been conducted : to evaluate the performance of the cab car corner and collision : posts of the Federal Railroad Administration's (FRA) : sponsored state-of-the-art (SOA) end frame design and the : Bombardie...
CFD Predictions for Transonic Performance of the ERA Hybrid Wing-Body Configuration
NASA Technical Reports Server (NTRS)
Deere, Karen A.; Luckring, James M.; McMillin, S. Naomi; Flamm, Jeffrey D.; Roman, Dino
2016-01-01
A computational study was performed for a Hybrid Wing Body configuration that was focused at transonic cruise performance conditions. In the absence of experimental data, two fully independent computational fluid dynamics analyses were conducted to add confidence to the estimated transonic performance predictions. The primary analysis was performed by Boeing with the structured overset-mesh code OVERFLOW. The secondary analysis was performed by NASA Langley Research Center with the unstructured-mesh code USM3D. Both analyses were performed at full-scale flight conditions and included three configurations customary to drag buildup and interference analysis: a powered complete configuration, the configuration with the nacelle/pylon removed, and the powered nacelle in isolation. The results in this paper are focused primarily on transonic performance up to cruise and through drag rise. Comparisons between the CFD results were very good despite some minor geometric differences in the two analyses.
NASA Astrophysics Data System (ADS)
Farhat, I. A. H.; Gale, E.; Alpha, C.; Isakovic, A. F.
2017-07-01
Optimizing energy performance of Magnetic Tunnel Junctions (MTJs) is the key for embedding Spin Transfer Torque-Random Access Memory (STT-RAM) in low power circuits. Due to the complex interdependencies of the parameters and variables of the device operating energy, it is important to analyse parameters with most effective control of MTJ power. The impact of threshold current density, Jco , on the energy and the impact of HK on Jco are studied analytically, following the expressions that stem from Landau-Lifshitz-Gilbert-Slonczewski (LLGS-STT) model. In addition, the impact of other magnetic material parameters, such as Ms , and geometric parameters such as tfree and λ is discussed. Device modelling study was conducted to analyse the impact at the circuit level. Nano-magnetism simulation based on NMAGTM package was conducted to analyse the impact of controlling HK on the switching dynamics of the film.
41 CFR 60-3.7 - Use of other validity studies.
Code of Federal Regulations, 2014 CFR
2014-07-01
... study was conducted perform substantially the same major work behaviors, as shown by appropriate job analyses both on the job or group of jobs on which the validity study was performed and on the job for...
41 CFR 60-3.7 - Use of other validity studies.
Code of Federal Regulations, 2013 CFR
2013-07-01
... study was conducted perform substantially the same major work behaviors, as shown by appropriate job analyses both on the job or group of jobs on which the validity study was performed and on the job for...
Mueller, Monika; D'Addario, Maddalena; Egger, Matthias; Cevallos, Myriam; Dekkers, Olaf; Mugglin, Catrina; Scott, Pippa
2018-05-21
Systematic reviews and meta-analyses of observational studies are frequently performed, but no widely accepted guidance is available at present. We performed a systematic scoping review of published methodological recommendations on how to systematically review and meta-analyse observational studies. We searched online databases and websites and contacted experts in the field to locate potentially eligible articles. We included articles that provided any type of recommendation on how to conduct systematic reviews and meta-analyses of observational studies. We extracted and summarised recommendations on pre-defined key items: protocol development, research question, search strategy, study eligibility, data extraction, dealing with different study designs, risk of bias assessment, publication bias, heterogeneity, statistical analysis. We summarised recommendations by key item, identifying areas of agreement and disagreement as well as areas where recommendations were missing or scarce. The searches identified 2461 articles of which 93 were eligible. Many recommendations for reviews and meta-analyses of observational studies were transferred from guidance developed for reviews and meta-analyses of RCTs. Although there was substantial agreement in some methodological areas there was also considerable disagreement on how evidence synthesis of observational studies should be conducted. Conflicting recommendations were seen on topics such as the inclusion of different study designs in systematic reviews and meta-analyses, the use of quality scales to assess the risk of bias, and the choice of model (e.g. fixed vs. random effects) for meta-analysis. There is a need for sound methodological guidance on how to conduct systematic reviews and meta-analyses of observational studies, which critically considers areas in which there are conflicting recommendations.
ERIC Educational Resources Information Center
Carriere, Ronald A.; And Others
This report focuses on a set of supplemental analyses that were performed on portions of the Emergency School Aid Act (ESAA) evaluation data. The goal of these analyses was to explore additional relationships in the data that might help to inform program policy, to confirm and/or further explicate some of the findings reported earlier, and to put…
Information filtering via biased heat conduction.
Liu, Jian-Guo; Zhou, Tao; Guo, Qiang
2011-09-01
The process of heat conduction has recently found application in personalized recommendation [Zhou et al., Proc. Natl. Acad. Sci. USA 107, 4511 (2010)], which is of high diversity but low accuracy. By decreasing the temperatures of small-degree objects, we present an improved algorithm, called biased heat conduction, which could simultaneously enhance the accuracy and diversity. Extensive experimental analyses demonstrate that the accuracy on MovieLens, Netflix, and Delicious datasets could be improved by 43.5%, 55.4% and 19.2%, respectively, compared with the standard heat conduction algorithm and also the diversity is increased or approximately unchanged. Further statistical analyses suggest that the present algorithm could simultaneously identify users' mainstream and special tastes, resulting in better performance than the standard heat conduction algorithm. This work provides a creditable way for highly efficient information filtering.
Thermal finite-element analysis of space shuttle main engine turbine blade
NASA Technical Reports Server (NTRS)
Abdul-Aziz, Ali; Tong, Michael T.; Kaufman, Albert
1987-01-01
Finite-element, transient heat transfer analyses were performed for the first-stage blades of the space shuttle main engine (SSME) high-pressure fuel turbopump. The analyses were based on test engine data provided by Rocketdyne. Heat transfer coefficients were predicted by performing a boundary-layer analysis at steady-state conditions with the STAN5 boundary-layer code. Two different peak-temperature overshoots were evaluated for the startup transient. Cutoff transient conditions were also analyzed. A reduced gas temperature profile based on actual thermocouple data was also considered. Transient heat transfer analyses were conducted with the MARC finite-element computer code.
Basic Transportation Economics
NASA Technical Reports Server (NTRS)
Kneafsey, J. T.
1972-01-01
Transportation economics is an integral part of all transportation activities. Refined, detailed, and careful economic analyses consider conduct-performance methodology and the specifications of production, cost and demand functions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peace, Gerald; Goering, Timothy James; Miller, Mark Laverne
2007-01-01
A probabilistic performance assessment has been conducted to evaluate the fate and transport of radionuclides (americium-241, cesium-137, cobalt-60, plutonium-238, plutonium-239, radium-226, radon-222, strontium-90, thorium-232, tritium, uranium-238), heavy metals (lead and cadmium), and volatile organic compounds (VOCs) at the Mixed Waste Landfill (MWL). Probabilistic analyses were performed to quantify uncertainties inherent in the system and models for a 1,000-year period, and sensitivity analyses were performed to identify parameters and processes that were most important to the simulated performance metrics. Comparisons between simulated results and measured values at the MWL were made to gain confidence in the models and perform calibrations whenmore » data were available. In addition, long-term monitoring requirements and triggers were recommended based on the results of the quantified uncertainty and sensitivity analyses.« less
Evaluation of MARC for the analysis of rotating composite blades
NASA Technical Reports Server (NTRS)
Bartos, Karen F.; Ernst, Michael A.
1993-01-01
The suitability of the MARC code for the analysis of rotating composite blades was evaluated using a four-task process. A nonlinear displacement analysis and subsequent eigenvalue analysis were performed on a rotating spring mass system to ensure that displacement-dependent centrifugal forces were accounted for in the eigenvalue analysis. Normal modes analyses were conducted on isotropic plates with various degrees of twist to evaluate MARC's ability to handle blade twist. Normal modes analyses were conducted on flat composite plates to validate the newly developed coupled COBSTRAN-MARC methodology. Finally, normal modes analyses were conducted on four composite propfan blades that were designed, analyzed, and fabricated at NASA Lewis Research Center. Results were compared with experimental data. The research documented herein presents MARC as a viable tool for the analysis of rotating composite blades.
Evaluation of MARC for the analysis of rotating composite blades
NASA Astrophysics Data System (ADS)
Bartos, Karen F.; Ernst, Michael A.
1993-03-01
The suitability of the MARC code for the analysis of rotating composite blades was evaluated using a four-task process. A nonlinear displacement analysis and subsequent eigenvalue analysis were performed on a rotating spring mass system to ensure that displacement-dependent centrifugal forces were accounted for in the eigenvalue analysis. Normal modes analyses were conducted on isotropic plates with various degrees of twist to evaluate MARC's ability to handle blade twist. Normal modes analyses were conducted on flat composite plates to validate the newly developed coupled COBSTRAN-MARC methodology. Finally, normal modes analyses were conducted on four composite propfan blades that were designed, analyzed, and fabricated at NASA Lewis Research Center. Results were compared with experimental data. The research documented herein presents MARC as a viable tool for the analysis of rotating composite blades.
Recommendations for Improved Performance Appraisal in the Federal Sector
1986-01-01
camera-ready copy of a Participant’s Coursebook to be used in conducting sessions of the course, and (d) an evaluation instrument for use in obtaining...Timeliness and Availability of Departmental Statistics and Analyses Develop complete plans for conducting the 1990 census • Improve statistics on
Establishing Good Practices for Exposure–Response Analysis of Clinical Endpoints in Drug Development
Overgaard, RV; Ingwersen, SH; Tornøe, CW
2015-01-01
This tutorial aims at promoting good practices for exposure–response (E-R) analyses of clinical endpoints in drug development. The focus is on practical aspects of E-R analyses to assist modeling scientists with a process of performing such analyses in a consistent manner across individuals and projects and tailored to typical clinical drug development decisions. This includes general considerations for planning, conducting, and visualizing E-R analyses, and how these are linked to key questions. PMID:26535157
The paradox of intragroup conflict: a meta-analysis.
de Wit, Frank R C; Greer, Lindred L; Jehn, Karen A
2012-03-01
Since the meta-analysis by De Dreu and Weingart (2003b) on the effects of intragroup conflict on group outcomes, more than 80 new empirical studies of conflict have been conducted, often investigating more complex, moderated relationships between conflict and group outcomes, as well as new types of intragroup conflict, such as process conflict. To explore the trends in this new body of literature, we conducted a meta-analysis of 116 empirical studies of intragroup conflict (n = 8,880 groups) and its relationship with group outcomes. To address the heterogeneity across the studies included in the meta-analysis, we also investigated a number of moderating variables. Stable negative relationships were found between relationship and process conflict and group outcomes. In contrast to the results of De Dreu and Weingart, we did not find a strong and negative association between task conflict and group performance. Analyses of main effects as well as moderator analyses revealed a more complex picture. Task conflict and group performance were more positively related among studies where the association between task and relationship conflict was relatively weak, in studies conducted among top management teams rather than non-top management teams, and in studies where performance was measured in terms of financial performance or decision quality rather than overall performance.
Information filtering via biased heat conduction
NASA Astrophysics Data System (ADS)
Liu, Jian-Guo; Zhou, Tao; Guo, Qiang
2011-09-01
The process of heat conduction has recently found application in personalized recommendation [Zhou , Proc. Natl. Acad. Sci. USA PNASA60027-842410.1073/pnas.1000488107107, 4511 (2010)], which is of high diversity but low accuracy. By decreasing the temperatures of small-degree objects, we present an improved algorithm, called biased heat conduction, which could simultaneously enhance the accuracy and diversity. Extensive experimental analyses demonstrate that the accuracy on MovieLens, Netflix, and Delicious datasets could be improved by 43.5%, 55.4% and 19.2%, respectively, compared with the standard heat conduction algorithm and also the diversity is increased or approximately unchanged. Further statistical analyses suggest that the present algorithm could simultaneously identify users' mainstream and special tastes, resulting in better performance than the standard heat conduction algorithm. This work provides a creditable way for highly efficient information filtering.
Simulating Visual Attention Allocation of Pilots in an Advanced Cockpit Environment
NASA Technical Reports Server (NTRS)
Frische, F.; Osterloh, J.-P.; Luedtke, A.
2011-01-01
This paper describes the results of experiments conducted with human line pilots and a cognitive pilot model during interaction with a new 40 Flight Management System (FMS). The aim of these experiments was to gather human pilot behavior data in order to calibrate the behavior of the model. Human behavior is mainly triggered by visual perception. Thus, the main aspect was to setup a profile of human pilots' visual attention allocation in a cockpit environment containing the new FMS. We first performed statistical analyses of eye tracker data and then compared our results to common results of familiar analyses in standard cockpit environments. The comparison has shown a significant influence of the new system on the visual performance of human pilots. Further on, analyses of the pilot models' visual performance have been performed. A comparison to human pilots' visual performance revealed important improvement potentials.
Hart, Sara A; Petrill, Stephen A; Willcutt, Erik; Thompson, Lee A; Schatschneider, Christopher; Deater-Deckard, Kirby; Cutting, Laurie E
2010-11-01
Children with attention-deficit/hyperactivity disorder (ADHD) tend to perform more poorly on tests of reading and mathematical performance than their typical peers. Quantitative genetic analyses allow for a better understanding of the etiology of ADHD and reading and mathematics outcomes, by examining their common and unique genetic and environmental influences. Analyses were conducted on a sample 271 pairs of 10-year-old monozygotic and dizygotic twins drawn from the Western Reserve Reading and Mathematics Project. In general, the results suggested that the associations among ADHD symptoms, reading outcomes, and math outcomes were influenced by both general genetic and general shared-environment factors. The analyses also suggested significant independent genetic effects for ADHD symptoms. The results imply that differing etiological factors underlie the relationships among ADHD and reading and mathematics performance. It appears that both genetic and common family or school environments link ADHD with academic performance.
A profile of sports science research (1983-2003).
Williams, Stephen John; Kendall, Lawrence R
2007-08-01
A majority of sports science research is undertaken in universities and dedicated research centres, such as institutes of sport. Reviews of literature analysing and categorising research have been carried out, but categories identified have been limited to research design and data gathering techniques. Hence there is a need to include categories such as discipline, subjects and targeted sport. A study was conducted using document analysis method to gather data that described and categorised performance-based sports science research projects in Australian universities and institutes of sport. An instrument was designed that could be used by researchers to analyse and profile research in the area of sports science. The instrument contained six categories: targeted sport, primary study area, participant type, research setting, methodology and data gathering techniques. Research documents analysed consisted of 725 original unpublished research reports/theses. Results showed that over two-thirds of research projects were targeted to specific sports and, of this group, nearly half involved four sports: cycling, rowing, athletics and swimming. Overall, physiology was the most researched scientific discipline. The most frequently used research method was experimental design, and the most frequently used data gathering technique was physiological (performance) measures. Two-thirds of research was conducted in laboratory settings, and nearly half of the research was conducted with elite or sub-elite athletes as participants/subjects. The findings of this study provide an overall synopsis of performance-based sports science research conducted in Australia over the last 20 years, and should be of considerable importance in the ongoing development of sports science research policy in Australia.
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.
Effluent Monitoring Procedures: Basic Laboratory Skills. Staff Guide for Conducting the Course.
ERIC Educational Resources Information Center
Engel, William T.; And Others
This manual is designed for use by instructors who will have to teach others the basic laboratory skills needed to perform National Pollution Discharge Elimination System (NPDES) Analyses. It includes topics related to the presentation of training courses in which the NPDES analyses would be taught. These topics include: examples of course…
The Strategic Data Project's Strategic Performance Indicators
ERIC Educational Resources Information Center
Page, Lindsay C.; Fullerton, Jon; Bacher-Hicks, Andrew; Owens, Antoniya; Cohodes, Sarah R.; West, Martin R.; Glover, Sarah
2013-01-01
Strategic Performance Indicators (SPIs) are summary measures derived from parallel, descriptive analyses conducted across educational agencies. The SPIs are designed to inform agency management and efforts to improve student outcomes. We developed the SPIs to reveal patterns common across partner agencies, to highlight exceptions to those…
King, Robert; Parker, Simon; Mouzakis, Kon; Fletcher, Winston; Fitzgerald, Patrick
2007-11-01
The Integrated Task Modeling Environment (ITME) is a user-friendly software tool that has been developed to automatically recode low-level data into an empirical record of meaningful task performance. The present research investigated and validated the performance of the ITME software package by conducting complex simulation missions and comparing the task analyses produced by ITME with taskanalyses produced by experienced video analysts. A very high interrater reliability (> or = .94) existed between experienced video analysts and the ITME for the task analyses produced for each mission. The mean session time:analysis time ratio was 1:24 using video analysis techniques and 1:5 using the ITME. It was concluded that the ITME produced task analyses that were as reliable as those produced by experienced video analysts, and significantly reduced the time cost associated with these analyses.
Chen, Yi-Wen; Hunt, Michael A; Campbell, Kristin L; Peill, Kortni; Reid, W Darlene
2016-04-01
Many middle-aged and older persons have more than one chronic condition. Thus, it is important to synthesise the effectiveness of interventions across several comorbidities. The aim of this systematic review was to summarise current evidence regarding the effectiveness of Tai Chi in individuals with four common chronic conditions-cancer, osteoarthritis (OA), heart failure (HF) and chronic obstructive pulmonary disease (COPD). 4 databases (MEDLINE, EMBASE, CINAHL and SPORTDiscus) were searched for original articles. Two reviewers independently screened the titles and abstracts and then conducted full-text reviews, quality assessment and finally data abstraction. 33 studies met the inclusion criteria. Meta-analyses were performed on disease-specific symptoms, physiological outcomes and physical performance of each chronic condition. Subgroup analyses on disease-specific symptoms were conducted by categorising studies into subsets based on the type of comparison groups. Meta-analyses showed that Tai Chi improved or showed a tendency to improve physical performance outcomes, including 6-min walking distance (6MWD) and knee extensor strength, in most or all four chronic conditions. Tai Chi also improved disease-specific symptoms of pain and stiffness in OA. The results demonstrated a favourable effect or tendency of Tai Chi to improve physical performance and showed that this type of exercise could be performed by individuals with different chronic conditions, including COPD, HF and OA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Predictors of Neuropsychological Test Performance After Pediatric Traumatic Brain Injury
ERIC Educational Resources Information Center
Donders, Jacobus; Nesbit-Greene, Kelly
2004-01-01
The influence of neurological and demographic variables on neuropsychological test performance was examined in 100 9- to 16-year-old children with traumatic brain injury (TBI). Regression analyses were conducted to determine the relative contributions of coma, neuroimaging findings, ethnicity, socioeconomic status, and gender to variance in…
Scaling of Ion Thrusters to Low Power
NASA Technical Reports Server (NTRS)
Patterson, Michael J.; Grisnik, Stanley P.; Soulas, George C.
1998-01-01
Analyses were conducted to examine ion thruster scaling relationships in detail to determine performance limits, and lifetime expectations for thruster input power levels below 0.5 kW. This was motivated by mission analyses indicating the potential advantages of high performance, high specific impulse systems for small spacecraft. The design and development status of a 0.1-0.3 kW prototype small thruster and its components are discussed. Performance goals include thruster efficiencies on the order of 40% to 54% over a specific impulse range of 2000 to 3000 seconds, with a lifetime in excess of 8000 hours at full power. Thruster technologies required to achieve the performance and lifetime targets are identified.
Fire resistance properties of ceramic wool fiber reinforced intumescent coatings
NASA Astrophysics Data System (ADS)
Amir, N.; Othman, W. M. S. W.; Ahmad, F.
2015-07-01
This research studied the effects of varied weight percentage and length of ceramic wool fiber (CWF) reinforcement to fire retardant performance of epoxy-based intumescent coating. Ten formulations were developed using ammonium polyphosphate (APP), expandable graphite (EG), melamine (MEL) and boric acid (BA). The mixing was conducted in two stages; powdered materials were grinded in Rocklabs mortar grinder and epoxy-mixed using Caframo mixer at low speed mixing. The samples were applied on mild steel substrate and exposed to 500°C heat inside Carbolite electric furnace. The char expansion and its physical properties were observed. Scanning electron microscopy (SEM) analyses were conducted to inspect the fiber dispersion, fiber condition and the cell structure of both coatings and chars produced. Thermogravimetric analyses (TGA) were conducted to study the thermal properties of the coating such as degradation temperature and residual weight. Fire retardant performance was determined by measuring backside temperature of substrate in 1-hour, 1000°C Bunsen burner test according to UL 1709 fire regime. The results showed that intumescent coating reinforced with CWF produced better fire resistance performance. When compared to unreinforced coating, formulation S6-15 significantly reduced steel temperature at approximately 34.7% to around 175°C. However, higher fiber weight percentage had slightly decreased fire retardant performance of the coating.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Amir, N., E-mail: norlailiamir@petronas.com.my; Othman, W. M. S. W., E-mail: wamosa@gmail.com; Ahmad, F., E-mail: faizahmad@petronas.com.my
This research studied the effects of varied weight percentage and length of ceramic wool fiber (CWF) reinforcement to fire retardant performance of epoxy-based intumescent coating. Ten formulations were developed using ammonium polyphosphate (APP), expandable graphite (EG), melamine (MEL) and boric acid (BA). The mixing was conducted in two stages; powdered materials were grinded in Rocklabs mortar grinder and epoxy-mixed using Caframo mixer at low speed mixing. The samples were applied on mild steel substrate and exposed to 500°C heat inside Carbolite electric furnace. The char expansion and its physical properties were observed. Scanning electron microscopy (SEM) analyses were conducted tomore » inspect the fiber dispersion, fiber condition and the cell structure of both coatings and chars produced. Thermogravimetric analyses (TGA) were conducted to study the thermal properties of the coating such as degradation temperature and residual weight. Fire retardant performance was determined by measuring backside temperature of substrate in 1-hour, 1000°C Bunsen burner test according to UL 1709 fire regime. The results showed that intumescent coating reinforced with CWF produced better fire resistance performance. When compared to unreinforced coating, formulation S6-15 significantly reduced steel temperature at approximately 34.7% to around 175°C. However, higher fiber weight percentage had slightly decreased fire retardant performance of the coating.« less
ERIC Educational Resources Information Center
Fidalgo, Angel M.
2011-01-01
Mantel-Haenszel (MH) methods constitute one of the most popular nonparametric differential item functioning (DIF) detection procedures. GMHDIF has been developed to provide an easy-to-use program for conducting DIF analyses. Some of the advantages of this program are that (a) it performs two-stage DIF analyses in multiple groups simultaneously;…
ERIC Educational Resources Information Center
McKenney, Elizabeth L. W.; Waldron, Nancy; Conroy, Maureen
2013-01-01
This study describes the integrity with which 3 general education middle school teachers implemented functional analyses (FA) of appropriate behavior for students who typically engaged in disruption. A 4-step model consistent with behavioral consultation was used to support the assessment process. All analyses were conducted during ongoing…
Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Building Structures
Çelebi, Mehmet
1998-01-01
Several approaches are used to assess the performance of the built environment following an earthquake -- preliminary damage surveys conducted by professionals, detailed studies of individual structures, and statistical analyses of groups of structures. Reports of damage that are issued by many organizations immediately following an earthquake play a key role in directing subsequent detailed investigations. Detailed studies of individual structures and statistical analyses of groups of structures may be motivated by particularly good or bad performance during an earthquake. Beyond this, practicing engineers typically perform stress analyses to assess the performance of a particular structure to vibrational levels experienced during an earthquake. The levels may be determined from recorded or estimated ground motions; actual levels usually differ from design levels. If a structure has seismic instrumentation to record response data, the estimated and recorded response and behavior of the structure can be compared.
Review of nutritional screening and assessment tools and clinical outcomes in heart failure.
Lin, Hong; Zhang, Haifeng; Lin, Zheng; Li, Xinli; Kong, Xiangqin; Sun, Gouzhen
2016-09-01
Recent studies have suggested that undernutrition as defined using multidimensional nutritional evaluation tools may affect clinical outcomes in heart failure (HF). The evidence supporting this correlation is unclear. Therefore, we conducted this systematic review to critically appraise the use of multidimensional evaluation tools in the prediction of clinical outcomes in HF. We performed descriptive analyses of all identified articles involving qualitative analyses. We used STATA to conduct meta-analyses when at least three studies that tested the same type of nutritional assessment or screening tools and used the same outcome were identified. Sensitivity analyses were conducted to validate our positive results. We identified 17 articles with qualitative analyses and 11 with quantitative analysis after comprehensive literature searching and screening. We determined that the prevalence of malnutrition is high in HF (range 16-90 %), particularly in advanced and acute decompensated HF (approximate range 75-90 %). Undernutrition as identified by multidimensional evaluation tools may be significantly associated with hospitalization, length of stay and complications and is particularly strongly associated with high mortality. The meta-analysis revealed that compared with other tools, Mini Nutritional Assessment (MNA) scores were the strongest predictors of mortality in HF [HR (4.32, 95 % CI 2.30-8.11)]. Our results remained reliable after conducting sensitivity analyses. The prevalence of malnutrition is high in HF, particularly in advanced and acute decompensated HF. Moreover, undernutrition as identified by multidimensional evaluation tools is significantly associated with unfavourable prognoses and high mortality in HF.
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…
Nuclear thermal rocket nozzle testing and evaluation program
NASA Technical Reports Server (NTRS)
Davidian, Kenneth O.; Kacynski, Kenneth J.
1993-01-01
Performance characteristics of the Nuclear Thermal Rocket can be enhanced through the use of unconventional nozzles as part of the propulsion system. The Nuclear Thermal Rocket nozzle testing and evaluation program being conducted at the NASA Lewis is outlined and the advantages of a plug nozzle are described. A facility description, experimental designs and schematics are given. Results of pretest performance analyses show that high nozzle performance can be attained despite substantial nozzle length reduction through the use of plug nozzles as compared to a convergent-divergent nozzle. Pretest measurement uncertainty analyses indicate that specific impulse values are expected to be within + or - 1.17 pct.
Composite Materials for Thermal Energy Storage: Enhancing Performance through Microstructures
Ge, Zhiwei; Ye, Feng; Ding, Yulong
2014-01-01
Chemical incompatibility and low thermal conductivity issues of molten-salt-based thermal energy storage materials can be addressed by using microstructured composites. Using a eutectic mixture of lithium and sodium carbonates as molten salt, magnesium oxide as supporting material, and graphite as thermal conductivity enhancer, the microstructural development, chemical compatibility, thermal stability, thermal conductivity, and thermal energy storage performance of composite materials are investigated. The ceramic supporting material is essential for preventing salt leakage and hence provides a solution to the chemical incompatibility issue. The use of graphite gives a significant enhancement on the thermal conductivity of the composite. Analyses suggest that the experimentally observed microstructural development of the composite is associated with the wettability of the salt on the ceramic substrate and that on the thermal conduction enhancer. PMID:24591286
Behaviour of fractional loop delay zero crossing digital phase locked loop (FR-ZCDPLL)
NASA Astrophysics Data System (ADS)
Nasir, Qassim
2018-01-01
This article analyses the performance of the first-order zero crossing digital phase locked loops (FR-ZCDPLL) when fractional loop delay is added to loop. The non-linear dynamics of the loop is presented, analysed and examined through bifurcation behaviour. Numerical simulation of the loop is conducted to proof the mathematical analysis of the loop operation. The results of the loop simulation show that the proposed FR-ZCDPLL has enhanced the performance compared to the conventional zero crossing DPLL in terms of wider lock range, captured range and stable operation region. In addition, extensive experimental simulation was conducted to find the optimum loop parameters for different loop environmental conditions. The addition of the fractional loop delay network in the conventional loop also reduces the phase jitter and its variance especially when the signal-to-noise ratio is low.
TAP 2: A finite element program for thermal analysis of convectively cooled structures
NASA Technical Reports Server (NTRS)
Thornton, E. A.
1980-01-01
A finite element computer program (TAP 2) for steady-state and transient thermal analyses of convectively cooled structures is presented. The program has a finite element library of six elements: two conduction/convection elements to model heat transfer in a solid, two convection elements to model heat transfer in a fluid, and two integrated conduction/convection elements to represent combined heat transfer in tubular and plate/fin fluid passages. Nonlinear thermal analysis due to temperature-dependent thermal parameters is performed using the Newton-Raphson iteration method. Transient analyses are performed using an implicit Crank-Nicolson time integration scheme with consistent or lumped capacitance matrices as an option. Program output includes nodal temperatures and element heat fluxes. Pressure drops in fluid passages may be computed as an option. User instructions and sample problems are presented in appendixes.
Analysis of swimming performance: perceptions and practices of US-based swimming coaches.
Mooney, Robert; Corley, Gavin; Godfrey, Alan; Osborough, Conor; Newell, John; Quinlan, Leo Richard; ÓLaighin, Gearóid
2016-01-01
In elite swimming, a broad range of methods are used to assess performance, inform coaching practices and monitor athletic progression. The aim of this paper was to examine the performance analysis practices of swimming coaches and to explore the reasons behind the decisions that coaches take when analysing performance. Survey data were analysed from 298 Level 3 competitive swimming coaches (245 male, 53 female) based in the United States. Results were compiled to provide a generalised picture of practices and perceptions and to examine key emerging themes. It was found that a disparity exists between the importance swim coaches place on biomechanical analysis of swimming performance and the types of analyses that are actually conducted. Video-based methods are most frequently employed, with over 70% of coaches using these methods at least monthly, with analyses being mainly qualitative in nature rather than quantitative. Barriers to the more widespread use of quantitative biomechanical analysis in elite swimming environments were explored. Constraints include time, cost and availability of resources, but other factors such as sources of information on swimming performance and analysis and control over service provision are also discussed, with particular emphasis on video-based methods and emerging sensor-based technologies.
Monte Carlo simulations for generic granite repository studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chu, Shaoping; Lee, Joon H; Wang, Yifeng
In a collaborative study between Los Alamos National Laboratory (LANL) and Sandia National Laboratories (SNL) for the DOE-NE Office of Fuel Cycle Technologies Used Fuel Disposition (UFD) Campaign project, we have conducted preliminary system-level analyses to support the development of a long-term strategy for geologic disposal of high-level radioactive waste. A general modeling framework consisting of a near- and a far-field submodel for a granite GDSE was developed. A representative far-field transport model for a generic granite repository was merged with an integrated systems (GoldSim) near-field model. Integrated Monte Carlo model runs with the combined near- and farfield transport modelsmore » were performed, and the parameter sensitivities were evaluated for the combined system. In addition, a sub-set of radionuclides that are potentially important to repository performance were identified and evaluated for a series of model runs. The analyses were conducted with different waste inventory scenarios. Analyses were also conducted for different repository radionuelide release scenarios. While the results to date are for a generic granite repository, the work establishes the method to be used in the future to provide guidance on the development of strategy for long-term disposal of high-level radioactive waste in a granite repository.« less
Modified RS2101 rocket engine study program
NASA Technical Reports Server (NTRS)
1971-01-01
The purpose of the program is to perform design studies and analyses to determine the effects of incorporating a 60:1 expansion area ratio nozzle extension, extended firing time, and modified operating conditions and environments on the MM'71 rocket engine assembly. An injector-to-thrust chamber seal study was conducted to define potential solutions for leakage past this joint. The results and recommendations evolving from the engine thermal analyses, the injector-to-thrust chamber seal studies, and the nozzle extension joint stress analyses are presented.
Hart, Sara A.; Petrill, Stephen A.; Willcutt, Erik; Thompson, Lee A.; Schatschneider, Christopher; Deater-Deckard, Kirby; Cutting, Laurie E.
2013-01-01
Children with attention-deficit/hyperactivity disorder (ADHD) tend to perform more poorly on tests of reading and mathematical performance than their typical peers. Quantitative genetic analyses allow for a better understanding of the etiology of ADHD and reading and mathematics outcomes, by examining their common and unique genetic and environmental influences. Analyses were conducted on a sample 271 pairs of 10-year-old monozygotic and dizygotic twins drawn from the Western Reserve Reading and Mathematics Project. In general, the results suggested that the associations among ADHD symptoms, reading outcomes, and math outcomes were influenced by both general genetic and general shared-environment factors. The analyses also suggested significant independent genetic effects for ADHD symptoms. The results imply that differing etiological factors underlie the relationships among ADHD and reading and mathematics performance. It appears that both genetic and common family or school environments link ADHD with academic performance. PMID:20966487
Fuel tank integrity research : fuel tank analyses and test plans
DOT National Transportation Integrated Search
2013-04-15
The Federal Railroad Administrations Office of Research : and Development is conducting research into fuel tank : crashworthiness. Fuel tank research is being performed to : determine strategies for increasing the fuel tank impact : resistance to ...
Providing Relevance in Chemistry for Nursing Students
ERIC Educational Resources Information Center
Jones, Theodore H. D.
1976-01-01
Describes an introductory chemistry course for nurses in which students learn basic chemical principles by performing 12 chemical analyses that are routinely conducted on body fluids and listed on a patient's clinical laboratory chart. (MLH)
Applying U.S. EOP Analytical Justification Experience for VVER Plants in the Ukraine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Linn, Paul A.; Julian, Harold V.; Chapman, James R.
2002-07-01
The foundation for new Emergency Operating Instructions (EOIs) being developed at several plants in the Ukraine is the Westinghouse Owners Group (WOG) Emergency Response Guidelines (ERGs) developed in the U.S. The ERGs were chosen as a base for the new EOIs for several reasons. First the overall structure and format was adaptable to VVER Pressurized Water Reactor (PWR) designs. Second, the ERGs have served as a base for many plant EOIs in both the U.S. and internationally. Third, key information supporting the ERGs was available. This paper describes the method used at one of the Ukrainian plants to provide anmore » analytical justification for their EOIs. The method being employed by a second plant is very similar, differing only slightly in how it is implemented. The WOG ERG development program, which started shortly after the accident at Three Mile Island Unit 2, used many sources of technical information on plant and system transient response, which were available in support of the plant design and licensing efforts. In addition, operating experience from many operating PWR plants in the U.S. and around the world was used. For example, design basis accident (DBA) analyses, documented in a plant's Safety Analysis Report (SAR) and other design documents, had been performed by Nuclear Steam Supply System (NSSS) vendors, utilities, or the Architect/Engineer. All relevant sources were considered in the development of the ERGs. Limited Probabilistic Risk Assessment (PRA) analyses were available during that time period. When a technical basis for a recovery strategy and associated operator actions was not available, an analysis was defined and performed. In general, these analyses were performed on a generic basis, and addressed the different categories of design (e.g., number of reactor coolant loops and/or low/high pressure safety injection system design). U.S. Nuclear Power plants that were in the WOG program were responsible for implementing the generic ERGs. This required the utilities to review the generic analyses to ensure that they were applicable and to justify any deviations from the ERG methodology. Modern PRA analyses are similar to the analyses supporting the ERGs since they address multiple failures and assume better estimate or expected assumptions for equipment availability and operator performance. The process being employed by Ukrainian plants is similar to the WOG. That is, available analyses and operating experience are being reviewed and pertinent information extracted to assist in the analytical justification of the EOIs. This includes the use of recently updated PRA and DBA analyses, other 'original' design information and operating experience. A systematic review of the EOIs is being conducted to identify items requiring analytical justification. For each analysis identified, the specific purpose of the analysis is being documented. The analysis needs are then compared to the available analyses and operating experience. From this review, new analyses needed to justify the EOIs are developed, and a basis for using existing analyses is established. The work is being conducted in two phases. The first phase performs all of the reviews and assessments necessary to determine the new analyses required to justify the EOIs. In the second phase, these new analyses will be conducted and documented, and the EOI Analytical Justification (AJ) report will be written. (authors)« less
Sensitivity analysis of FeCrAl cladding and U3Si2 fuel under accident conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gamble, Kyle Allan Lawrence; Hales, Jason Dean
2016-08-01
The purpose of this milestone report is to highlight the results of sensitivity analyses performed on two accident tol- erant fuel concepts: U3Si2 fuel and FeCrAl cladding. The BISON fuel performance code under development at Idaho National Laboratory was coupled to Sandia National Laboratories’ DAKOTA software to perform the sensitivity analyses. Both Loss of Coolant (LOCA) and Station blackout (SBO) scenarios were analyzed using main effects studies. The results indicate that for FeCrAl cladding the input parameters with greatest influence on the output metrics of interest (fuel centerline temperature and cladding hoop strain) during the LOCA were the isotropic swellingmore » and fuel enrichment. For U3Si2 the important inputs were found to be the intergranular diffusion coefficient, specific heat, and fuel thermal conductivity. For the SBO scenario, Young’s modulus was found to be influential in FeCrAl in addition to the isotropic swelling and fuel enrichment. Contrarily to the LOCA case, the specific heat of U3Si2 was found to have no effect during the SBO. The intergranular diffusion coefficient and fuel thermal conductivity were still found to be of importance. The results of the sensitivity analyses have identified areas where further research is required including fission gas behavior in U3Si2 and irradiation swelling in FeCrAl. Moreover, the results highlight the need to perform the sensitivity analyses on full length fuel rods for SBO scenarios.« less
Structural tailoring of counter rotation propfans
NASA Technical Reports Server (NTRS)
Brown, Kenneth W.; Hopkins, D. A.
1989-01-01
The STAT program was designed for the optimization of single rotation, tractor propfan designs. New propfan designs, however, generally consist of two counter rotating propfan rotors. STAT is constructed to contain two levels of analysis. An interior loop, consisting of accurate, efficient approximate analyses, is used to perform the primary propfan optimization. Once an optimum design has been obtained, a series of refined analyses are conducted. These analyses, while too computer time expensive for the optimization loop, are of sufficient accuracy to validate the optimized design. Should the design prove to be unacceptable, provisions are made for recalibration of the approximate analyses, for subsequent reoptimization.
ERIC Educational Resources Information Center
Linn, Robert L.
The New Standards Project conducted a pilot test of a series of performance-based assessment tasks in mathematics and English language arts at Grades 4 and 8 in the spring of 1993. This paper reports the results of a series of generalizability analyses conducted for a subset of the 1993 pilot study data in mathematics. Generalizability analyses…
Neal, B; MacMahon, S
1999-01-01
Overviews (meta-analyses) of the major ongoing randomized trials of blood pressure lowering drugs will be conducted to determine the effects of: first, newer versus older classes of blood pressure lowering drugs in patients with hypertension; and second, blood pressure lowering treatments versus untreated or less treated control conditions in patient groups at high risk of cardiovascular events. The principal study outcomes are stroke, coronary heart disease, total cardiovascular events and total cardiovascular deaths. The overviews have been prospectively designed and will be conducted on individual patient data. The analyses will be conducted as a collaboration between the principal investigators of participating trials involving about 270,000 patients. Full data should be available in 2003, with the first round of analyses performed in 1999-2000. The combination of trial results should provide good statistical power to detect even modest differences between the effects on the main study outcomes.
McEwan, Desmond; Ruissen, Geralyn R.; Eys, Mark A.; Zumbo, Bruno D.; Beauchamp, Mark R.
2017-01-01
The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed. PMID:28085922
Composite materials for thermal energy storage: enhancing performance through microstructures.
Ge, Zhiwei; Ye, Feng; Ding, Yulong
2014-05-01
Chemical incompatibility and low thermal conductivity issues of molten-salt-based thermal energy storage materials can be addressed by using microstructured composites. Using a eutectic mixture of lithium and sodium carbonates as molten salt, magnesium oxide as supporting material, and graphite as thermal conductivity enhancer, the microstructural development, chemical compatibility, thermal stability, thermal conductivity, and thermal energy storage performance of composite materials are investigated. The ceramic supporting material is essential for preventing salt leakage and hence provides a solution to the chemical incompatibility issue. The use of graphite gives a significant enhancement on the thermal conductivity of the composite. Analyses suggest that the experimentally observed microstructural development of the composite is associated with the wettability of the salt on the ceramic substrate and that on the thermal conduction enhancer. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Warren, L.P.; Church, P.E.; Turtora, Michael
1996-01-01
Hydraulic conductivities of a sand and gravel aquifer were estimated by three methods: constant- head multiport-permeameter tests, grain-size analyses (with the Hazen approximation method), and slug tests. Sediment cores from 45 boreholes were undivided or divided into two or three vertical sections to estimate hydraulic conductivity based on permeameter tests and grain-size analyses. The cores were collected from depth intervals in the screened zone of the aquifer in each observation well. Slug tests were performed on 29 observation wells installed in the boreholes. Hydraulic conductivities of 35 sediment cores estimated by use of permeameter tests ranged from 0.9 to 86 meters per day, with a mean of 22.8 meters per day. Hydraulic conductivities of 45 sediment cores estimated by use of grain-size analyses ranged from 0.5 to 206 meters per day, with a mean of 40.7 meters per day. Hydraulic conductivities of aquifer material at 29 observation wells estimated by use of slug tests ranged from 0.6 to 79 meters per day, with a mean of 32.9 meters per day. The repeatability of estimated hydraulic conductivities were estimated to be within 30 percent for the permeameter method, 12 percent for the grain-size method, and 9.5 percent for the slug test method. Statistical tests determined that the medians of estimates resulting from the slug tests and grain-size analyses were not significantly different but were significantly higher than the median of estimates resulting from the permeameter tests. Because the permeameter test is the only method considered which estimates vertical hydraulic conductivity, the difference in estimates may be attributed to vertical or horizontal anisotropy. The difference in the average hydraulic conductivities estimated by use of each method was less than 55 percent when compared to the estimated hydraulic conductivity determined from an aquifer test conducted near the study area.
Hedin, Riley J; Umberham, Blake A; Detweiler, Byron N; Kollmorgen, Lauren; Vassar, Matt
2016-10-01
Systematic reviews and meta-analyses are used by clinicians to derive treatment guidelines and make resource allocation decisions in anesthesiology. One cause for concern with such reviews is the possibility that results from unpublished trials are not represented in the review findings or data synthesis. This problem, known as publication bias, results when studies reporting statistically nonsignificant findings are left unpublished and, therefore, not included in meta-analyses when estimating a pooled treatment effect. In turn, publication bias may lead to skewed results with overestimated effect sizes. The primary objective of this study is to determine the extent to which evaluations for publication bias are conducted by systematic reviewers in highly ranked anesthesiology journals and which practices reviewers use to mitigate publication bias. The secondary objective of this study is to conduct publication bias analyses on the meta-analyses that did not perform these assessments and examine the adjusted pooled effect estimates after accounting for publication bias. This study considered meta-analyses and systematic reviews from 5 peer-reviewed anesthesia journals from 2007 through 2015. A PubMed search was conducted, and full-text systematic reviews that fit inclusion criteria were downloaded and coded independently by 2 authors. Coding was then validated, and disagreements were settled by consensus. In total, 207 systematic reviews were included for analysis. In addition, publication bias evaluation was performed for 25 systematic reviews that did not do so originally. We used Egger regression, Duval and Tweedie trim and fill, and funnel plots for these analyses. Fifty-five percent (n = 114) of the reviews discussed publication bias, and 43% (n = 89) of the reviews evaluated publication bias. Funnel plots and Egger regression were the most common methods for evaluating publication bias. Publication bias was reported in 34 reviews (16%). Thirty-six of the 45 (80.0%) publication bias analyses indicated the presence of publication bias by trim and fill analysis, whereas Egger regression indicated publication bias in 23 of 45 (51.1%) analyses. The mean absolute percent difference between adjusted and observed point estimates was 15.5%, the median was 6.2%, and the range was 0% to 85.5%. Many of these reviews reported following published guidelines such as PRISMA or MOOSE, yet only half appropriately addressed publication bias in their reviews. Compared with previous research, our study found fewer reviews assessing publication bias and greater likelihood of publication bias among reviews not performing these evaluations.
RAM simulation model for SPH/RSV systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schryver, J.C.; Primm, A.H.; Nelson, S.C.
1995-12-31
The US Army`s Project Manager, Crusader is sponsoring the development of technologies that apply to the Self-Propelled Howitzer (SPH), formerly the Advanced Field Artillery System (AFAS), and Resupply Vehicle (RSV), formerly the Future Armored Resupply Vehicle (FARV), weapon system. Oak Ridge National Laboratory (ORNL) is currently performing developmental work in support of the SPH/PSV Crusader system. Supportive analyses of reliability, availability, and maintainability (RAM) aspects were also performed for the SPH/RSV effort. During FY 1994 and FY 1995 OPNL conducted a feasibility study to demonstrate the application of simulation modeling for RAM analysis of the Crusader system. Following completion ofmore » the feasibility study, a full-scale RAM simulation model of the Crusader system was developed for both the SPH and PSV. This report provides documentation for the simulation model as well as instructions in the proper execution and utilization of the model for the conduct of RAM analyses.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stillman, J. A.; Feldman, E. E.; Jaluvka, D.
This report contains the results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members in the Research and Test Reactor Department at the Argonne National Laboratory (ANL) and the MURR Facility. MURR LEU conversion is part of an overall effort to develop and qualify high-density fuel within the U.S. High Performance Research Reactor Conversion (USHPRR) program conducted by the U.S. Department of Energy National Nuclearmore » Security Administration’s Office of Material Management and Minimization (M 3).« less
Nuclear thermal rocket nozzle testing and evaluation program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davidian, K.O.; Kacynski, K.J.
Performance characteristics of the Nuclear Thermal Rocket can be enhanced through the use of unconventional nozzles as part of the propulsion system. In this report, the Nuclear Thermal Rocket nozzle testing and evaluation program being conducted at the NASA Lewis Research Center is outlined and the advantages of a plug nozzle are described. A facility description, experimental designs and schematics are given. Results of pretest performance analyses show that high nozzle performance can be attained despite substantial nozzle length reduction through the use of plug nozzles as compared to a convergent-divergent nozzle. Pretest measurement uncertainty analyses indicate that specific impulsemore » values are expected to be within plus or minus 1.17%.« less
ERIC Educational Resources Information Center
Agasisti, Tommaso; Haelermans, Carla
2016-01-01
This paper analyses the relationship between the public funding systems of higher education in Italy and the Netherlands and their universities' performances. Empirically, an efficiency analysis on 13 Dutch and 58 Italian public universities is conducted. The findings show that the relative efficiency of Italian and Dutch universities is strongly…
ERIC Educational Resources Information Center
Kieffer, Kevin M.; Schinka, John A.; Curtiss, Glenn
2004-01-01
This study examined the contributions of the 5-Factor Model (FFM; P. T. Costa & R. R. McCrae, 1992) and RIASEC (J. L. Holland, 1994) constructs of consistency, differentiation, and person-environment congruence in predicting job performance ratings in a large sample (N = 514) of employees. Hierarchical regression analyses conducted separately by…
The Politics of Desire and Possibility in Urban Playwriting: (Re)reading and (Re)writing the Script
ERIC Educational Resources Information Center
Winn, Maisha T.
2012-01-01
In this article, the author analyses scripts written by incarcerated girls in playwriting and performance workshops conducted in regional youth detention centres and performed by formerly incarcerated girls in a programme called "Girl Time" in an urban American southeastern city. Through a close reading and analysis of characters, plots…
ERIC Educational Resources Information Center
Carrera-Fernández, María Victoria; Lameiras-Fernández, María; Rodríguez-Castro, Yolanda
2018-01-01
The purpose of the present study was to analyse adolescents' perception of bullying and particularly of the ways intelligible masculinities and femininities are performed through violence in the framework of Queer Theory. We conducted a qualitative study using focus groups. The sample was composed of 93 Spanish adolescents (48 girls and 45 boys,…
Evaluating the interior thermal performance of mosques in the tropical environment
NASA Astrophysics Data System (ADS)
Nordin, N. I.; Misni, A.
2018-02-01
This study introduces the methodology applied in conducting data collection and data analysis. Data collection is the process of gathering and measuring information on targeted variables in an established systematic method. Qualitative and quantitative methods are combined in collecting data from government departments, site experiments and observation. Furthermore, analysing the indoor thermal performance data in the heritage and new mosques were used thermal monitoring tests, while validation will be made by meteorology data. Origin 8 version of the software is used to analyse all the data. Comparison techniques were applied to analyse several factors that influence the indoor thermal performance of mosques, namely building envelope include floor area, opening, and material used. Building orientation, location, surrounding vegetation and water elements are also recorded as supported building primary data. The comparison of primary data using these variables for four mosques include heritage and new buildings were revealed.
DOT National Transportation Integrated Search
2017-06-30
The ever-increasing processing speed and computational power of computers and simulation systems has led to correspondingly larger, more sophisticated representations of evacuation traffic processes. Today, micro-level analyses can be conducted for m...
Demonstration of using quieter pavement in Death Valley National Park
DOT National Transportation Integrated Search
2013-06-01
Death Valley National Park provided an environment that allowed a demonstration of : quieter pavement use. Sound measurements near the tire-pavement interface, near the : road, and in areas of frequent human use were conducted and analyses performed ...
Inlet Flow Valve Engine Analyses
NASA Technical Reports Server (NTRS)
Champagne, G. A.
2004-01-01
Pratt&Whitney, under Task Order 13 of the NASA Large Engine Technology (LET) Contract, conducted a study to determine the operating characteristics, performance and weights of Inlet Flow Valve (IFV) propulsion concepts for a Mach 2.4 High Speed Civil Transport (HSCT).
Two-dimensional model of a Space Station Freedom thermal energy storage canister
NASA Astrophysics Data System (ADS)
Kerslake, Thomas W.; Ibrahim, Mounir B.
1990-08-01
The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase change salt containment canister. A 2-D, axisymmetric finite difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions and forced convection in the heat engine working fluid. Void shape, location, growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between ground based canister performance (in l-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.
Two-dimensional model of a Space Station Freedom thermal energy storage canister
NASA Astrophysics Data System (ADS)
Kerslake, Thomas W.; Ibrahim, Mounir B.
The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase-change salt containment canister. A 2-D, axisymmetric finite-difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions, and forced convection in the heat engine working fluid. Void shape, location, and growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between groundbased canister performance (in 1-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.
Two-dimensional model of a Space Station Freedom thermal energy storage canister
NASA Technical Reports Server (NTRS)
Kerslake, Thomas W.; Ibrahim, Mounir B.
1990-01-01
The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase-change salt containment canister. A 2-D, axisymmetric finite-difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions, and forced convection in the heat engine working fluid. Void shape, location, and growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between groundbased canister performance (in 1-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.
Two-dimensional model of a Space Station Freedom thermal energy storage canister
NASA Technical Reports Server (NTRS)
Kerslake, Thomas W.; Ibrahim, Mounir B.
1990-01-01
The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase change salt containment canister. A 2-D, axisymmetric finite difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions and forced convection in the heat engine working fluid. Void shape, location, growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between ground based canister performance (in l-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.
The performance assessment of undergraduate students in physics laboratory by using guided inquiry
NASA Astrophysics Data System (ADS)
Mubarok, H.; Lutfiyah, A.; Kholiq, A.; Suprapto, N.; Putri, N. P.
2018-03-01
The performance assessment of basic physics experiment among undergraduate physics students which includes three stages: pre-laboratory, conducting experiment and final report was explored in this study. The research used a descriptive quantitative approach by utilizing guidebook of basic physics experiment. The findings showed that (1) the performance of pre-laboratory rate among undergraduate physics students in good category (average score = 77.55), which includes the ability of undergraduate physics students’ theory before they were doing the experiment. (2) The performance of conducting experiment was in good category (average score = 78.33). (3) While the performance of final report was in moderate category (average score = 73.73), with the biggest weakness at how to analyse and to discuss the data and writing the abstract.
Space Storable Propellant Performance Gas/Liquid Like-Doublet Injector Characterization
NASA Technical Reports Server (NTRS)
Falk, A. Y.
1972-01-01
A 30-month applied research program was conducted, encompassing an analytical, design, and experimental effort to relate injector design parameters to simultaneous attainment of high performance and component (injector/thrust chamber) compatibility for gas/liquid space-storable propellants. The gas/liquid propellant combination selected for study was FLOX (82.6% F2)/ambient temperature gaseous methane. The injector pattern characterized was the like-(self)-impinging doublet. Program effort was apportioned into four basic technical tasks: injector and thrust chamber design, injector and thrust chamber fabrication, performance evaluation testing, and data evaluation and reporting. Analytical parametric combustion analyses and cold flow distribution and atomization experiments were conducted with injector segment models to support design of injector/thrust chamber combinations for hot fire evaluation. Hot fire tests were conducted to: (1) optimize performance of the injector core elements, and (2) provide design criteria for the outer zone elements so that injector/thrust chamber compatibility could be achieved with only minimal performance losses.
Performance-based management and quality of work: an empirical assessment.
Falzon, Pierre; Nascimento, Adelaide; Gaudart, Corinne; Piney, Cécile; Dujarier, Marie-Anne; Germe, Jean-François
2012-01-01
In France, in the private sector as in the public sector, performance-based management tends to become a norm. Performance-based management is supposed to improve service quality, productivity and efficiency, transparency of allotted means and achieved results, and to better focus the activity of employees and of the whole organization. This text reports a study conducted for the French Ministry of Budget by a team of researchers in ergonomics, sociology and management science, in order to assess the impact of performance-based management on employees, on teams and on work organization. About 100 interviews were conducted with employees of all categories and 6 working groups were set up in order to discuss and validate or amend our first analyses. Results concern several aspects: workload and work intensification, indicators and performance management and the transformation of jobs induced by performance management.
Design considerations for a Space Shuttle Main Engine turbine blade made of single crystal material
NASA Technical Reports Server (NTRS)
Abdul-Aziz, A.; August, R.; Nagpal, V.
1993-01-01
Nonlinear finite-element structural analyses were performed on the first stage high-pressure fuel turbopump blade of the Space Shuttle Main Engine. The analyses examined the structural response and the dynamic characteristics at typical operating conditions. Single crystal material PWA-1480 was considered for the analyses. Structural response and the blade natural frequencies with respect to the crystal orientation were investigated. The analyses were conducted based on typical test stand engine cycle. Influence of combined thermal, aerodynamic, and centrifugal loadings was considered. Results obtained showed that the single crystal secondary orientation effects on the maximum principal stresses are not highly significant.
NASA Technical Reports Server (NTRS)
Eder, D.
1992-01-01
Parametric models were constructed for Earth-based laser powered electric orbit transfer from low Earth orbit to geosynchronous orbit. These models were used to carry out performance, cost/benefit, and sensitivity analyses of laser-powered transfer systems including end-to-end life cycle cost analyses for complete systems. Comparisons with conventional orbit transfer systems were made indicating large potential cost savings for laser-powered transfer. Approximate optimization was done to determine best parameter values for the systems. Orbit transfer flights simulations were conducted to explore effects of parameters not practical to model with a spreadsheet. The simulations considered view factors that determine when power can be transferred from ground stations to an orbit transfer vehicle and conducted sensitivity analyses for numbers of ground stations, Isp including dual-Isp transfers, and plane change profiles. Optimal steering laws were used for simultaneous altitude and plane change. Viewing geometry and low-thrust orbit raising were simultaneously simulated. A very preliminary investigation of relay mirrors was made.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laes, Denise; Eisinger, Chris; Morgan, Craig
2013-07-30
The purpose of this report is to provide a summary of individual local-scale CCS site characterization studies conducted in Colorado, New Mexico and Utah. These site- specific characterization analyses were performed as part of the “Characterization of Most Promising Sequestration Formations in the Rocky Mountain Region” (RMCCS) project. The primary objective of these local-scale analyses is to provide a basis for regional-scale characterization efforts within each state. Specifically, limits on time and funding will typically inhibit CCS projects from conducting high- resolution characterization of a state-sized region, but smaller (< 10,000 km{sup 2}) site analyses are usually possible, and suchmore » can provide insight regarding limiting factors for the regional-scale geology. For the RMCCS project, the outcomes of these local-scale studies provide a starting point for future local-scale site characterization efforts in the Rocky Mountain region.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-08
... analytical method using enzyme- linked immunosorbent assay (ELISA) analyses for the qualitative detection of... study conducted by an independent third party laboratory to evaluate the ELISA test kit's performance as...
DOT National Transportation Integrated Search
2017-06-01
Performance analyses of newly constructed linear BMPs in retaining stormwater run-off from 1 in. precipitation in : post-construction highway applications and urban areas were conducted using numerical simulations and field : observation. A series of...
ERIC Educational Resources Information Center
Tse, Chi-Shing; Altarriba, Jeanette
2012-01-01
By administering a Stroop task to college-student bilinguals varied in self-rated first- (L1) and second-language (L2) proficiency, the current study examined the effects of L1 and L2 proficiencies on selective attention performance. We conducted ex-Gaussian analyses to capture the modal and positive-tail components of participants' reaction time…
Smith, Andrew P
2005-08-01
There is a large literature on the effects of caffeine on performance. Most of the studies have been conducted in the laboratory and further information is required on the effects of caffeine consumption on performance and safety at work. The present studies aimed to determine whether the level of caffeine consumption influenced changes in alertness and performance over the working day. Secondary analyses of a large epidemiological database were also conducted to examine associations between caffeine consumption and cognitive failures and accidents at work. In the first study 110 volunteers, all of whom were regular caffeine consumers, rated their alertness and carried out a simple reaction time task before and after work on a Monday and Friday. Caffeine consumption during the day was recorded and volunteers were sub-divided into low and high consumers on the basis of a median split (220 mg/day). The second study involved secondary analyses of a database formed by combining the Bristol Stress and Health at Work and Cardiff Health and Safety at Work studies. In the first analyses associations between caffeine consumption and frequency of cognitive failures were examined in a sample of 1253 white-collar workers. The second set of analyses examined associations between caffeine consumption and accidents at work in a sample of 1555 workers who were especially at risk of having an accident. The results from the first study showed that those who consumed higher levels of caffeine reported significantly greater increases in alertness over the working day and a significantly smaller slowing of reaction time. The results from the second study demonstrated significant associations between caffeine consumption and fewer cognitive failures and accidents at work. After controlling for possible confounding factors it was found that higher caffeine consumption was associated with about half the risk of frequent/very frequent cognitive failures and a similar reduction in risk for accidents at work. Overall, the results from the three analyses show that caffeine consumption may have benefits for performance and safety at work. Copyright (c) 2005 John Wiley & Sons, Ltd.
Yu, Yao; Hu, Hao; Bohlender, Ryan J; Hu, Fulan; Chen, Jiun-Sheng; Holt, Carson; Fowler, Jerry; Guthery, Stephen L; Scheet, Paul; Hildebrandt, Michelle A T; Yandell, Mark; Huff, Chad D
2018-04-06
High-throughput sequencing data are increasingly being made available to the research community for secondary analyses, providing new opportunities for large-scale association studies. However, heterogeneity in target capture and sequencing technologies often introduce strong technological stratification biases that overwhelm subtle signals of association in studies of complex traits. Here, we introduce the Cross-Platform Association Toolkit, XPAT, which provides a suite of tools designed to support and conduct large-scale association studies with heterogeneous sequencing datasets. XPAT includes tools to support cross-platform aware variant calling, quality control filtering, gene-based association testing and rare variant effect size estimation. To evaluate the performance of XPAT, we conducted case-control association studies for three diseases, including 783 breast cancer cases, 272 ovarian cancer cases, 205 Crohn disease cases and 3507 shared controls (including 1722 females) using sequencing data from multiple sources. XPAT greatly reduced Type I error inflation in the case-control analyses, while replicating many previously identified disease-gene associations. We also show that association tests conducted with XPAT using cross-platform data have comparable performance to tests using matched platform data. XPAT enables new association studies that combine existing sequencing datasets to identify genetic loci associated with common diseases and other complex traits.
ERIC Educational Resources Information Center
Rasmusson, Maria; Åberg-Bengtsson, Lisbeth
2015-01-01
Data from a Swedish PISA-sample were used (1) to identify a digital reading factor, (2) to investigate gender differences in this factor (if found), and (3) to explore how computer game playing might relate to digital reading performance and gender. The analyses were conducted with structural equation modeling techniques. In addition to an overall…
Repeatability and uncertainty analyses of NASA/MSFC light gas gun test data
NASA Technical Reports Server (NTRS)
Schonberg, William P.; Cooper, David
1993-01-01
This Final Report presents an overview of the impact tests performed at NASA/MSFC in the time period 1985 to 1991 and the results of phenomena repeatability and data uncertainty studies performed using the information obtained from those tests. An analysis of the data from over 400 tests conducted between 1989 and 1991 was performed to generate a database to supplement the Hypervelocity Impact Damage Database developed under a previous effort.
Transportation systems analyses. Volume 2: Technical/programmatics
NASA Astrophysics Data System (ADS)
1993-05-01
The principal objective of this study is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform man delivery and return, cargo transfer, cargo delivery, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationships between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. This report documents the three principal transportation systems analyses (TSA) efforts during the period 7 November 92 - 6 May 93. The analyses are as follows: Mixed-Fleet (STS/ELV) strategies for SSF resupply; Transportation Systems Data Book - overview; and Operations Cost Model - overview/introduction.
Assessment of technical condition of concrete pavement by the example of district road
NASA Astrophysics Data System (ADS)
Linek, M.; Nita, P.; Żebrowski, W.; Wolka, P.
2018-05-01
The article presents the comprehensive assessment of concrete pavement condition. Analyses included the district road located in the swietokrzyskie province, used for 11 years. Comparative analyses were conducted twice. The first analysis was carried out after 9 years of pavement operation, in 2015. In order to assess the extent of pavement degradation, the tests were repeated in 2017. Within the scope of field research, the traffic intensity within the analysed road section was determined. Visual assessment of pavement condition was conducted, according to the guidelines included in SOSN-B. Visual assessment can be extended by ground-penetrating radar measurements which allow to provide comprehensive assessment of the occurred structure changes within its entire thickness and length. The assessment included also performance parameters, i.e. pavement regularity, surface roughness and texture. Extension of test results by the assessment of changes in internal structure of concrete composite and structure observations by means of Scanning Electron Microscope allow for the assessment of parameters of internal structure of hardened concrete. Supplementing the observations of internal structure by means of computed tomography scan provides comprehensive information of possible discontinuities and composite structure. According to the analysis of the obtained results, conclusions concerning the analysed pavement condition were reached. It was determined that the pavement is distinguished by high performance parameters, its condition is good and it does not require any repairs. Maintenance treatment was suggested in order to extend the period of proper operation of the analysed pavement.
NASA Astrophysics Data System (ADS)
Tanaka, Manabu; Takeda, Yasushi; Wakiya, Takeru; Wakamoto, Yuta; Harigaya, Kaori; Ito, Tatsunori; Tarao, Takashi; Kawakami, Hiroyoshi
2017-02-01
High-performance polymer electrolyte membranes (PEMs) with excellent proton conductivity, gas barrier property, and membrane stability are desired for future fuel cells. Here we report the development of PEMs based on our proposed new concept "Nanofiber Framework (NfF)." The NfF composite membranes composed of phytic acid-doped polybenzimidazole nanofibers (PBINf) and Nafion matrix show higher proton conductivity than the recast-Nafion membrane without nanofibers. A series of analyses reveal the formation of three-dimensional network nanostructures to conduct protons and water effectively through acid-condensed layers at the interface of PBINf and Nafion matrix. In addition, the NfF composite membrane achieves high gas barrier property and distinguished membrane stability. The fuel cell performance by the NfF composite membrane, which enables ultra-thin membranes with their thickness less than 5 μm, is superior to that by the recast-Nafion membrane, especially at low relative humidity. Such NfF-based high-performance PEM will be accomplished not only by the Nafion matrix used in this study but also by other polymer electrolyte matrices for future PEFCs.
Race and diurnal blood pressure patterns. A review and meta-analysis.
Profant, J; Dimsdale, J E
1999-05-01
Investigators have reported variable findings regarding the role of race in diurnal blood pressure patterns. We performed a review and meta-analysis of this literature to identify the overall effect of race on circadian blood pressure patterns. Eighteen studies involving 2852 participants were reviewed. Meta-analyses were conducted using effect sizes calculated from the data provided directly in the study reports. Separate meta-analyses were conducted on effect sizes for differences between blacks and whites in daytime and nighttime systolic and diastolic blood pressure and nocturnal dip in systolic and diastolic blood pressure. To evaluate discrepancies in findings from studies involving American versus non-American blacks, overall meta-analyses as well as within-subset meta-analyses of black/white differences were conducted for comparisons involving American and non-American blacks. Results of overall meta-analyses indicate that blacks experience higher levels of systolic and diastolic blood pressure, both at night and during the day. These differences were significantly greater at night than during the day (P<0.05). Results of within-subset analyses involving American blacks mirrored those for all black/white comparisons, except that the effect of race on nocturnal dip, ie, that American blacks experienced less of a dip in both systolic and diastolic blood pressure at night, was significant (P<0.05). In contrast, the effect of race on nocturnal dip was not significant for comparisons involving non-American blacks. These results suggest a consistent difference in the chronobiology of blood pressure, particularly in American blacks.
Orbital refill of propulsion vehicle tankage
NASA Technical Reports Server (NTRS)
Merino, F.; Risberg, J. A.; Hill, M.
1980-01-01
Techniques for orbital refueling of space based vehicles were developed and experimental programs to verify these techniques were identified. Orbital refueling operations were developed for two cryogenic orbital transfer vehicles (OTV's) and an Earth storable low thrust liquid propellant vehicle. Refueling operations were performed assuming an orbiter tanker for near term missions and an orbital depot. Analyses were conducted using liquid hydrogen and N2O4. The influence of a pressurization system and acquisition device on operations was also considered. Analyses showed that vehicle refill operations will be more difficult with a cryogen than with an earth storable. The major elements of a successful refill with cryogens include tank prechill and fill. Propellant quantities expended for tank prechill appear to to insignificant. Techniques were identified to avoid loss of liquid or excessive tank pressures during refill. It was determined that refill operations will be similar whether or not an orbiter tanker or orbital depot is available. Modeling analyses were performed for prechill and fill tests to be conducted assuming the Spacelab as a test bed, and a 1/10 scale model OTV (with LN2 as a test fluid) as an experimental package.
NASA Technical Reports Server (NTRS)
Guo, Liwen; Cardullo, Frank M.; Kelly, Lon C.
2007-01-01
This report summarizes the results of delay measurement and piloted performance tests that were conducted to assess the effectiveness of the adaptive compensator and the state space compensator for alleviating the phase distortion of transport delay in the visual system in the VMS at the NASA Langley Research Center. Piloted simulation tests were conducted to assess the effectiveness of two novel compensators in comparison to the McFarland predictor and the baseline system with no compensation. Thirteen pilots with heterogeneous flight experience executed straight-in and offset approaches, at various delay configurations, on a flight simulator where different predictors were applied to compensate for transport delay. The glideslope and touchdown errors, power spectral density of the pilot control inputs, NASA Task Load Index, and Cooper-Harper rating of the handling qualities were employed for the analyses. The overall analyses show that the adaptive predictor results in slightly poorer compensation for short added delay (up to 48 ms) and better compensation for long added delay (up to 192 ms) than the McFarland compensator. The analyses also show that the state space predictor is fairly superior for short delay and significantly superior for long delay than the McFarland compensator.
Evaluation of dredged material proposed for ocean disposal from Hudson River, New York
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gardiner, W.W.; Barrows, E.S.; Antrim, L.D.
1996-09-01
The Hudson River (Federal Project No. 41) was one of seven waterways that the U.S. Army Corps of Engineers-New York District (USACE-NYD) requested the Battelle Marine Sciences Laboratory (MSL) to sample and evaluate for dredging and disposal in March 1994. Sediment samples were collected from the Hudson River. Tests and analyses were conducted on Hudson River sediment core samples. The evaluation of proposed dredged material from the Hudson River included bulk sediment chemical analyses, chemical analyses of site water and elutriate, water-column and benthic acute toxicity tests, and bioaccumulation studies. Individual sediment core samples collected from Hudson River were analyzedmore » for grain size, moisture content, and total organic carbon (TOC). A composite sediment sample, representing the entire area proposed for dredging, was analyzed for bulk density, specific gravity, metals, chlorinated pesticides, polychlorinated biphenyl (PCB) congeners, polynuclear aromatic hydrocarbons (PAH), and 1,4-dichlorobenzene. Site water and elutriate water, prepared from the suspended-particulate phase (SPP) of Hudson River sediment, were analyzed for metals, pesticides, and PCBS. Water-column or SPP toxicity tests were performed with three species. Benthic acute toxicity tests were performed. Bioaccumulation tests were also conducted.« less
Anatomy of a Nanoscale Conduction Channel Reveals the Mechanism of a High-Performance Memristor
NASA Astrophysics Data System (ADS)
Miao, Feng; Strachan, John Paul; Yang, J. Joshua; Yi, Wei; Goldfarb, Ilan; Zhang, M.-X.; Torrezan, Antonio C.; Eschbach, Peter; Kelley, Ronald D.; Medeiros-Ribeiro, Gilberto; Williams, R. Stanley
2012-02-01
Two major challenges for resistance memory devices (memristors) based on conductivity changes in oxide materials are better performance and understanding of the microscopic picture of the switching. After researchers' relentless pursuit for years, tantalum oxide-based memristors have rapidly risen to be the top candidate, showing fast speed, high endurance and excellent scalability. While the microscopic picture of these devices remains obscure, by employing a precise method for locating and directly visualizing the conduction channel, here we observed a nanoscale channel consisting of an amorphous Ta(O) solid solution surrounded by crystalline Ta2O5. Structural and chemical analyses of the channel combined with temperature dependent transport measurements revealed a unique resistance switching mechanism: the modulation of the channel elemental composition, and thus the conductivity, by the cooperative influence of drift, diffusion and thermophoresis, which seem to enable the high switching performance observed. (Miao*, Strachan*, Yang* et al., Advanced Materials. DOI: 10.1002/adma201103379 (2011))
Cycle 0(CY1991) NLS trade studies and analyses report. Book 1: Structures and core vehicle
NASA Technical Reports Server (NTRS)
1992-01-01
This report (SR-1: Structures, Trades, and Analysis), documents the Core Tankage Trades and analyses performed in support of the National Launch System (NLS) Cycle 0 preliminary design activities. The report covers trades that were conducted on the Vehicle Assembly, Fwd Skirt, LO2 Tank, Intertank, LH2 Tank, and Aft Skirt of the NLS Core Tankage. For each trade study, a two page executive summary and the detail trade study are provided. The trade studies contain study results, recommended changes to the Cycle 0 Baselines, and suggested follow on tasks to be performed during Cycle 1.
Studies to assess the impact of nighttime work zone lighting on motorists.
DOT National Transportation Integrated Search
2013-05-01
This report describes the methodology and results of analyses performed to assess the impact of work zone lighting on motorists. Field studies were conducted to provide insight into how drivers eyes react to typical temporary work zone lighting co...
Analyses performed using the rigid pavement database in Texas.
DOT National Transportation Integrated Search
2004-04-01
This report is the fifth out of six reports prepared for Research Project 0-1778 TxDOT Rigid Pavement : Database, conducted by the Center for Transportation Research (CTR) of the University of Texas at Austin : and funded by the Texas Departmen...
Integrated vehicle-based safety systems : heavy-truck field operational test key findings report.
DOT National Transportation Integrated Search
2010-08-01
This document presents key findings from the heavy-truck field operational test conducted as : part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of : analyses performed by the University of Michigan Transporta...
Integrated vehicle-based safety systems light-vehicle field operational test key findings report.
DOT National Transportation Integrated Search
2011-01-01
This document presents key findings from the light-vehicle field operational test conducted as part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of analyses performed by the University of Michigan Transportati...
Integrated vehicle-based safety systems light-vehicle field operational test key findings report.
DOT National Transportation Integrated Search
2011-01-01
"This document presents key findings from the light-vehicle field operational test conducted as part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of analyses performed by the University of Michigan Transportat...
The Development and Use of a Flight Optimization System Model of a C-130E Transport Aircraft
NASA Technical Reports Server (NTRS)
Desch, Jeremy D.
1995-01-01
The Systems Analysis Branch at NASA Langley Research Center conducts a variety of aircraft design and analyses studies. These studies include the prediction of characteristics of a particular conceptual design, analyses of designs that already exist, and assessments of the impact of technology on current and future aircraft. The FLight OPtimization System (FLOPS) is a tool used for aircraft systems analysis and design. A baseline input model of a Lockheed C-130E was generated for the Flight Optimization System. This FLOPS model can be used to conduct design-trade studies and technology impact assessments. The input model was generated using standard input data such as basic geometries and mission specifications. All of the other data needed to determine the airplane performance is computed internally by FLOPS. The model was then calibrated to reproduce the actual airplane performance from flight test data. This allows a systems analyzer to change a specific item of geometry or mission definition in the FLOPS input file and evaluate the resulting change in performance from the output file. The baseline model of the C-130E was used to analyze the effects of implementing upper wing surface blowing on the airplane. This involved removing the turboprop engines that were on the C-130E and replacing them with turbofan engines. An investigation of the improvements in airplane performance with the new engines could be conducted within the Flight Optimization System. Although a thorough analysis was not completed, the impact of this change on basic mission performance was investigated.
Numerical simulation of unsteady free surface flow and dynamic performance for a Pelton turbine
NASA Astrophysics Data System (ADS)
Xiao, Y. X.; Cui, T.; Wang, Z. W.; Yan, Z. G.
2012-11-01
Different from the reaction turbines, the hydraulic performance of the Pelton turbine is dynamic due to the unsteady free surface flow in the rotating buckets in time and space. This paper aims to present the results of investigations conducted on the free surface flow in a Pelton turbine rotating buckets. The unsteady numerical simulations were performed with the CFX code by using the Realizable k-ε turbulence model coupling the two-phase flow volume of fluid method. The unsteady free surface flow patterns and torque varying with the bucket rotating were analysed. The predicted relative performance at five operating conditions was compared with the field test results. The study was also conducted the interactions between the bucket rear and the water jet.
Cyclic performance tests of Sn/MWCNT composite lithium ion battery anodes at different temperatures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tocoglu, U., E-mail: utocoglu@sakarya.edu.tr; Cevher, O.; Akbulut, H.
In this study tin-multi walled carbon nanotube (Sn-MWCNT) lithium ion battery anodes were produced and their electrochemical galvanostatic charge/discharge tests were conducted at various (25 °C, 35 °C, 50 °C) temperatures to determine the cyclic behaviors of anode at different temperatures. Anodes were produced via vacuum filtration and DC magnetron sputtering technique. Tin was sputtered onto buckypapers to form composite structure of anodes. SEM analysis was conducted to determine morphology of buckypapers and Sn-MWCNT composite anodes. Structural and phase analyses were conducted via X-ray diffraction and Raman Spectroscopy technique. CR2016 coin cells were assembled for electrochemical tests. Cyclic voltammetry testmore » were carried out to determine the reversibility of reactions between anodes and reference electrode between 0.01-2.0 V potential window. Galvanostatic charge/discharge tests were performed to determine cycle performance of anodes at different temperatures.« less
Video Games vs. Reading and School/Cognitive Performances: A Study on 27000 Middle School Teenagers
ERIC Educational Resources Information Center
Lieury, Alain; Lorant, Sonia; Trosseille, Bruno; Champault, Françoise; Vourc'h, Ronan
2016-01-01
Video games are a very common leisure activity among teenagers and the aim of this study is to analyse their relations with cognitive and school performances. This study is part of a broad survey, conducted on 27,000 French teenagers (14.5 years old) in middle school (9th grade). The survey contained both a questionnaire on leisure activities…
Orion Flight Performance Design Trades
NASA Technical Reports Server (NTRS)
Jackson, Mark C.; Straube, Timothy
2010-01-01
A significant portion of the Orion pre-PDR design effort has focused on balancing mass with performance. High level performance metrics include abort success rates, lunar surface coverage, landing accuracy and touchdown loads. These metrics may be converted to parameters that affect mass, such as ballast for stabilizing the abort vehicle, propellant to achieve increased lunar coverage or extended missions, or ballast to increase the lift-to-drag ratio to improve entry and landing performance. The Orion Flight Dynamics team was tasked to perform analyses to evaluate many of these trades. These analyses not only provide insight into the physics of each particular trade but, in aggregate, they illustrate the processes used by Orion to balance performance and mass margins, and thereby make design decisions. Lessons learned can be gleaned from a review of these studies which will be useful to other spacecraft system designers. These lessons fall into several categories, including: appropriate application of Monte Carlo analysis in design trades, managing margin in a highly mass-constrained environment, and the use of requirements to balance margin between subsystems and components. This paper provides a review of some of the trades and analyses conducted by the Flight Dynamics team, as well as systems engineering lessons learned.
CENTRIFUGAL VIBRATION TEST OF RC PILE FOUNDATION
NASA Astrophysics Data System (ADS)
Higuchi, Shunichi; Tsutsumiuchi, Takahiro; Otsuka, Rinna; Ito, Koji; Ejiri, Joji
It is necessary that nonlinear responses of structures are clarified by soil-structure interaction analysis for the purpose of evaluating the seismic performances of underground structure or foundation structure. In this research, centrifuge shake table tests of reinforced concrete pile foundation installed in the liquefied ground were conducted. Then, finite element analyses for the tests were conducted to confirm an applicability of the analytical method by comparing the experimental results and analytical results.
A Low Cost, Self Acting, Liquid Hydrogen Boil-Off Recovery System
NASA Technical Reports Server (NTRS)
Pelfrey, Joy W.; Sharp, Kirk V. (Technical Monitor)
2001-01-01
The purpose of this research was to develop a prototype liquid hydrogen boll-off recovery system. Perform analyses to finalize recovery system cycle, design detail components, fabricate hardware, and conduct sub-component, component, and system level tests leading to the delivery of a prototype system. The design point and off-design analyses identified cycle improvements to increase the robustness of the system by adding a by-pass heat exchanger. Based on the design, analysis, and testing conducted, the recovery system will liquefy 31% of the gaseous boil off from a liquid hydrogen storage tank. All components, including a high speed, miniature turbocompressor, were designed and manufacturing drawings were created. All hardware was fabricated and tests were conducted in air, helium, and hydrogen. Testing validated the design, except for the turbocompressor. A rotor-to-stator clearance issue was discovered as a result of a concentricity tolerance stack-up.
Predicting the seismic performance of typical R/C healthcare facilities: emphasis on hospitals
NASA Astrophysics Data System (ADS)
Bilgin, Huseyin; Frangu, Idlir
2017-09-01
Reinforced concrete (RC) type of buildings constitutes an important part of the current building stock in earthquake prone countries such as Albania. Seismic response of structures during a severe earthquake plays a vital role in the extent of structural damage and resulting injuries and losses. In this context, this study evaluates the expected performance of a five-story RC healthcare facility, representative of common practice in Albania, designed according to older codes. The design was based on the code requirements used in this region during the mid-1980s. Non-linear static and dynamic time history analyses were conducted on the structural model using the Zeus NL computer program. The dynamic time history analysis was conducted with a set of ground motions from real earthquakes. The building responses were estimated in global levels. FEMA 356 criteria were used to predict the seismic performance of the building. The structural response measures such as capacity curve and inter-story drift under the set of ground motions and pushover analyses results were compared and detailed seismic performance assessment was done. The main aim of this study is considering the application and methodology for the earthquake performance assessment of existing buildings. The seismic performance of the structural model varied significantly under different ground motions. Results indicate that case study building exhibit inadequate seismic performance under different seismic excitations. In addition, reasons for the poor performance of the building is discussed.
Side impact test and analyses of a DOT-111 tank car : final report.
DOT National Transportation Integrated Search
2015-10-01
Transportation Technology Center, Inc. conducted a side impact test on a DOT-111 tank car to evaluate the performance of the : tank car under dynamic impact conditions and to provide data for the verification and refinement of a computational model. ...
DOT National Transportation Integrated Search
2010-12-01
"This document presents the methodology and results from the heavy-truck field operational test conducted as part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of analyses performed by the University of Michiga...
DOT National Transportation Integrated Search
2010-12-01
"This document presents the methodology and results from the light-vehicle field operational test conducted as part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of analyses performed by the University of Michi...
CATREG SOFTWARE FOR CATEGORICAL REGRESSION ANALYSIS
CatReg is a computer program, written in the R (http://cran.r-project.org) programming language, to support the conduct of exposure-response analyses by toxicologists and health scientists. CatReg can be used to perform categorical regressi...
Innovativeness and the Organizational Attributes of Schools.
ERIC Educational Resources Information Center
Eidell, Terry L.; And Others
Five papers focus on the interrelated themes of school organization and innovation. They report on some preliminary analyses of field studies conducted during 1968 on such structural, sociocultural, and sociopsychological variables as division of labor, performance of organizational functions, decision making studies and processes, hierarchies of…
Guidelines for collection and field analysis of water-quality samples from streams in Texas
Wells, F.C.; Gibbons, W.J.; Dorsey, M.E.
1990-01-01
Analyses for unstable constituents or properties are by necessity performed in the field. This manual addresses analytical techniques and quality assurance for: (1) Water temperature; (2) specific conductance; (3) pH; (4) alkalinity; (5) dissolved oxygen; and (6) bacteria.
Emotional and cognitive effects of peer tutoring among secondary school mathematics students
NASA Astrophysics Data System (ADS)
Alegre Ansuategui, Francisco José; Moliner Miravet, Lidón
2017-11-01
This paper describes an experience of same-age peer tutoring conducted with 19 eighth-grade mathematics students in a secondary school in Castellon de la Plana (Spain). Three constructs were analysed before and after launching the program: academic performance, mathematics self-concept and attitude of solidarity. Students' perceptions of the method were also analysed. The quantitative data was gathered by means of a mathematics self-concept questionnaire, an attitude of solidarity questionnaire and the students' numerical ratings. A statistical analysis was performed using Student's t-test. The qualitative information was gathered by means of discussion groups and a field diary. This information was analysed using descriptive analysis and by categorizing the information. Results show statistically significant improvements in all the variables and the positive assessment of the experience and the interactions that took place between the students.
Computational Analyses of Offset Stream Nozzles for Noise Reduction
NASA Technical Reports Server (NTRS)
Dippold, Vance, III; Foster, Lancert; Wiese,Michael
2007-01-01
The Wind computational fluid dynamics code was used to perform a series of simulations on two offset stream nozzle concepts for jet noise reduction. The first concept used an S-duct to direct the secondary stream to the lower side of the nozzle. The second concept used vanes to turn the secondary flow downward. The analyses were completed in preparation of tests conducted in the NASA Glenn Research Center Aeroacoustic Propulsion Laboratory. The offset stream nozzles demonstrated good performance and reduced the amount of turbulence on the lower side of the jet plume. The computer analyses proved instrumental in guiding the development of the final test configurations and giving insight into the flow mechanics of offset stream nozzles. The computational predictions were compared with flowfield results from the jet rig testing and showed excellent agreement.
Residual Stresses and Critical Initial Flaw Size Analyses of Welds
NASA Technical Reports Server (NTRS)
Brust, Frederick W.; Raju, Ivatury, S.; Dawocke, David S.; Cheston, Derrick
2009-01-01
An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). A series of weld analyses are performed to determine the residual stresses in a critical region of the USS. Weld residual stresses both increase constraint and mean stress thereby having an important effect on the fatigue life. The purpose of the weld analyses was to model the weld process using a variety of sequences to determine the 'best' sequence in terms of weld residual stresses and distortions. The many factors examined in this study include weld design (single-V, double-V groove), weld sequence, boundary conditions, and material properties, among others. The results of this weld analysis are included with service loads to perform a fatigue and critical initial flaw size evaluation.
Lin, Dongxin; Ou, Qianting; Lin, Jialing; Peng, Yang; Yao, Zhenjiang
2017-04-01
Health care workers may potentially spread Staphylococcus aureus and methicillin-resistant S aureus (MRSA) to patients by contaminated high-touch items. We aimed to determine the pooled rates of S aureus and MRSA contamination and influencing factors. A literature search of the PubMed, ScienceDirect, Embase, Ovid, and Scopus databases was performed. Pooled contamination rates were determined using random effect models. Subgroup and meta-regression analyses were conducted to identify factors potentially influencing the rates of S aureus and MRSA contamination. Sensitivity and publication bias analyses were performed. Thirty-eight studies were included in the meta-analysis. The pooled contamination rates were 15.0% (95% confidence interval [CI], 9.8%-21.1%) for S aureus and 5.0% (95% CI, 2.7%-7.7%) for MRSA. The subgroup analyses indicated that the pooled rate of S aureus contamination was significantly higher for studies conducted in South America, in developing countries, and during 2010-2015. The pooled rate of MRSA contamination was significantly higher for studies conducted in Africa. The meta-regression analysis suggested that the pooled rate of S aureus contamination was lower for studies conducted in developed countries (odds ratio, 0.664; 95% CI, 0.509-0.867; P = .004). No bias was found in the publication of the rates of S aureus and MRSA contamination. S aureus and MRSA contamination statuses of high-touch items are worrisome and should be paid greater attention. Developing country status was a risk factor for S aureus contamination. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
No category specificity in Alzheimer's disease: a normal aging effect.
Moreno-Martínez, F Javier; Laws, Keith R
2008-07-01
The authors examined category effects on tasks of picture naming, naming to definition, and word-picture matching in 38 patients with Alzheimer's disease (AD) and 30 elderly controls. Each task was matched across category on all "nuisance" variables known to differ across domains. Standard analyses revealed significant category disadvantages for classifying living things in AD patients but also for elderly controls on each task. To overcome the ceiling effect in controls, the authors conducted 1,000 bootstrap analyses of covariance, with control performance as a difficulty index covariate. These covariate analyses eliminated the category effect in AD patients on all 3 tasks. Indeed, the authors report that control performance accounted for 64% (picture naming), 49% (naming to description), and 42% (word-picture matching) of variance in AD performance. This suggests that, although category effects in AD patients do not reflect intrinsic variables, the size and direction of the category effect are not different from those in elderly controls. PsycINFO Database Record (c) 2008 APA, all rights reserved.
Verster, Joris C; Roth, Thomas
2012-01-01
It is generally assumed that there are minimal gender differences in the safety and efficacy of central nervous system drugs, as is evidenced by men and women receiving the same drug dosage. There is, however, evidence that drugs may have a differential effect on performance in men and women, given reported differences in pharmacokinetics as well as the presence or absence and severity of adverse effects. It is especially important to verify whether gender differences in performance exist in case of activities that have potentially dangerous outcomes such as driving a car. This review summarizes the current scientific evidence on gender differences in driving performance after treatment with hypnotic drugs. A literature search was conducted to obtain all studies that conducted on-road driving tests to examine the effects hypnotic drugs on driving. Cross-references were checked and technical reports and raw data were obtained, if possible. Fourteen studies were evaluated. Many studies did not allow analyses of gender effects because only women were included. Others did not report data on gender analyses. Technical reports and additional data analyses revealed significant gender differences in driving performance the morning following bedtime administration of flurazepam (30 mg) and after middle-of-the-night administration of zolpidem (10 mg). No significant gender differences were found for ramelteon (8 mg), lormetazepam (1 and 2 mg), zaleplon (10 and 20 mg), and zopiclone (7.5 mg). Although the available data are limited, the results show that significant gender differences have been found for some drugs but not others. Therefore, in the future more research is needed to reveal potential gender differences and to determine what mediates them.
Sensitivity analyses of factors influencing CMAQ performance for fine particulate nitrate.
Shimadera, Hikari; Hayami, Hiroshi; Chatani, Satoru; Morino, Yu; Mori, Yasuaki; Morikawa, Tazuko; Yamaji, Kazuyo; Ohara, Toshimasa
2014-04-01
Improvement of air quality models is required so that they can be utilized to design effective control strategies for fine particulate matter (PM2.5). The Community Multiscale Air Quality modeling system was applied to the Greater Tokyo Area of Japan in winter 2010 and summer 2011. The model results were compared with observed concentrations of PM2.5 sulfate (SO4(2-)), nitrate (NO3(-)) and ammonium, and gaseous nitric acid (HNO3) and ammonia (NH3). The model approximately reproduced PM2.5 SO4(2-) concentration, but clearly overestimated PM2.5 NO3(-) concentration, which was attributed to overestimation of production of ammonium nitrate (NH4NO3). This study conducted sensitivity analyses of factors associated with the model performance for PM2.5 NO3(-) concentration, including temperature and relative humidity, emission of nitrogen oxides, seasonal variation of NH3 emission, HNO3 and NH3 dry deposition velocities, and heterogeneous reaction probability of dinitrogen pentoxide. Change in NH3 emission directly affected NH3 concentration, and substantially affected NH4NO3 concentration. Higher dry deposition velocities of HNO3 and NH3 led to substantial reductions of concentrations of the gaseous species and NH4NO3. Because uncertainties in NH3 emission and dry deposition processes are probably large, these processes may be key factors for improvement of the model performance for PM2.5 NO3(-). The Community Multiscale Air Quality modeling system clearly overestimated the concentration of fine particulate nitrate in the Greater Tokyo Area of Japan, which was attributed to overestimation of production of ammonium nitrate. Sensitivity analyses were conducted for factors associated with the model performance for nitrate. Ammonia emission and dry deposition of nitric acid and ammonia may be key factors for improvement of the model performance.
Final Report: Posttest Analysis of Omega II Optical Specimens
DOE Office of Scientific and Technical Information (OSTI.GOV)
Newlander, C D; Fisher, J H
Preliminary posttest analyses have been completed on optical specimens exposed during the Omega II test series conducted on 14 July 2006. The Omega Facility, located at the Laboratory for Laser Energetics (LLE) at the University of Rochester was used to produce X-ray environments through the interaction of intense pulsed laser radiation upon germanium-loaded silica aerogels. The optical specimen testing was supported by GH Systems through experiment design, pre- and post-test analyses, specimen acquisition, and overall technical experience. The test specimens were fabricated and characterized by Surface Optics Corporation (SOC), San Diego, CA and were simple protected gold coatings on silicamore » substrates. Six test specimens were exposed, five filtered with thin beryllium foil filters, and one unfiltered which was exposed directly to the raw environment. The experimental objectives were: (1) demonstrate that tests of optical specimens could be performed at the Omega facility; (2) evaluate the use and survivability of beryllium foil filters as a function of thickness; (3) obtain damage data on optical specimens which ranged from no damage to damage; (4) correlate existing thermal response models with the damage data; (5) evaluate the use of the direct raw environment upon the specimen response and the ability/desirability to conduct sensitive optical specimen tests using the raw environment; and (6) initiate the development of a protocol for performing optical coatings/mirror tests. This report documents the activities performed by GH Systems in evaluating and using the environments provided by LLNL, the PUFFTFT analyses performed using those environments, and the calculated results compared to the observed and measured posttest data.« less
Several approaches are available for evaluating adverse effects in near coastal ecosystems. These range from performing toxicity tests with individual organisms on water column and sediment samples to conducting macrofaunal compositional analyses on pelagic and benthic communiti...
Impact of Instructional Design on Virtual Teamwork
ERIC Educational Resources Information Center
Rawlings, Melody
2012-01-01
The purpose of this participatory action research study was to answer the following research question: How does online instructional design impact students' virtual teamwork performance? Through the lens of social constructivism, a qualitative, in-depth multi-case study design was utilized to conduct document analyses, observations, and student…
Black Female Community College Students' Satisfaction: A National Regression Analysis
ERIC Educational Resources Information Center
Strayhorn, Terrell L.; Johnson, Royel M.
2014-01-01
Data from the Community College Student Experiences Questionnaire were analyzed for a sample of 315 Black women attending community colleges. Specifically, we conducted multivariate analyses to assess the relationship between background traits, commitments, engagement, academic performance, and satisfaction for Black women at community colleges.…
Evaluation of the SafeLane overlay system for crash reduction on bridge deck surfaces.
DOT National Transportation Integrated Search
2010-03-01
The winter performance of the SafeLane commercial overlay system has been evaluated at four installations on : bridge decks in the state of Minnesota. The study was conducted over a period of a total of three years. Analyses : included mechanical ...
System Level RBDO for Military Ground Vehicles using High Performance Computing
2008-01-01
platform. Only the analyses that required more than 24 processors were conducted on the Onyx 350 due to the limited number of processors on the...optimization constraints varied. The queues set the number of processors and number of finite element code licenses available to the analyses. sgi ONYX ...3900: unix 24 MIPS R16000 PROCESSORS 4 IR2 GRAPHICS PIPES 4 IR3 GRAPHICS PIPES 24 GBYTES MEMORY 36 GBYTES LOCAL DISK SPACE sgi ONYX 350: unix 32 MIPS
Performance Improvement Through Indexing of Turbine Airfoils. Part 2; Numerical Simulation
NASA Technical Reports Server (NTRS)
Griffin, Lisa W.; Huber, Frank W.; Sharma, Om P.
1996-01-01
An experimental/analytical study has been conducted to determine the performance improvements achievable by circumferentially indexing succeeding rows of turbine stator airfoils. A series of tests was conducted to experimentally investigate stator wake clocking effects on the performance of the space shuttle main engine (SSME) alternate turbopump development (ATD) fuel turbine test article (TTA). The results from this study indicate that significant increases in stage efficiency can be attained through application of this airfoil clocking concept. Details of the experiment and its results are documented in part 1 of this paper. In order to gain insight into the mechanisms of the performance improvement, extensive computational fluid dynamics (CFD) simulations were executed. The subject of the present paper is the initial results from the CFD investigation of the configurations and conditions detailed in part 1 of the paper. To characterize the aerodynamic environments in the experimental test series, two-dimensional (2D), time accurate, multistage, viscous analyses were performed at the TTA midspan. Computational analyses for five different circumferential positions of the first stage stator have been completed. Details of the computational procedure and the results are presented. The analytical results verify the experimentally demonstrated performance improvement and are compared with data whenever possible. Predictions of time-averaged turbine efficiencies as well as gas conditions throughout the flow field are presented. An initial understanding of the turbine performance improvement mechanism based on the results from this investigation is described.
2015-01-01
We present and discuss philosophy and methodology of chaotic evolution that is theoretically supported by chaos theory. We introduce four chaotic systems, that is, logistic map, tent map, Gaussian map, and Hénon map, in a well-designed chaotic evolution algorithm framework to implement several chaotic evolution (CE) algorithms. By comparing our previous proposed CE algorithm with logistic map and two canonical differential evolution (DE) algorithms, we analyse and discuss optimization performance of CE algorithm. An investigation on the relationship between optimization capability of CE algorithm and distribution characteristic of chaotic system is conducted and analysed. From evaluation result, we find that distribution of chaotic system is an essential factor to influence optimization performance of CE algorithm. We propose a new interactive EC (IEC) algorithm, interactive chaotic evolution (ICE) that replaces fitness function with a real human in CE algorithm framework. There is a paired comparison-based mechanism behind CE search scheme in nature. A simulation experimental evaluation is conducted with a pseudo-IEC user to evaluate our proposed ICE algorithm. The evaluation result indicates that ICE algorithm can obtain a significant better performance than or the same performance as interactive DE. Some open topics on CE, ICE, fusion of these optimization techniques, algorithmic notation, and others are presented and discussed. PMID:25879067
Pei, Yan
2015-01-01
We present and discuss philosophy and methodology of chaotic evolution that is theoretically supported by chaos theory. We introduce four chaotic systems, that is, logistic map, tent map, Gaussian map, and Hénon map, in a well-designed chaotic evolution algorithm framework to implement several chaotic evolution (CE) algorithms. By comparing our previous proposed CE algorithm with logistic map and two canonical differential evolution (DE) algorithms, we analyse and discuss optimization performance of CE algorithm. An investigation on the relationship between optimization capability of CE algorithm and distribution characteristic of chaotic system is conducted and analysed. From evaluation result, we find that distribution of chaotic system is an essential factor to influence optimization performance of CE algorithm. We propose a new interactive EC (IEC) algorithm, interactive chaotic evolution (ICE) that replaces fitness function with a real human in CE algorithm framework. There is a paired comparison-based mechanism behind CE search scheme in nature. A simulation experimental evaluation is conducted with a pseudo-IEC user to evaluate our proposed ICE algorithm. The evaluation result indicates that ICE algorithm can obtain a significant better performance than or the same performance as interactive DE. Some open topics on CE, ICE, fusion of these optimization techniques, algorithmic notation, and others are presented and discussed.
Modular C3 Interface Analysis (Flexible Intraconnect). Volume 1, Part 1
1980-04-01
was prepared in parallel with a separate Flexible^ Intraconnect design definition study conducted by Hughes Aircraft Company under F19628-77-O-0261...reported herein consists of Task I, Task II, and Task III of Phase I of an on-going study being conducted by the Air Force to develop a Flexible...Intraconnect for tactical C^ tivity. equipment connec- As evidenced by the quantity of analyses performed and docu- mented during the period of this study
Altitude Investigation of Performance of Turbine-propeller Engine and Its Components
NASA Technical Reports Server (NTRS)
Wallner, Lewis E; Saari, Martin J
1950-01-01
An investigation was conducted on a turbine-propeller engine in the NACA Lewis altitude wind tunnel at altitudes from 5000 to 35,000 feet. The applicability of generalized parameters to turbine-propeller engine data, analyses of the compressor, the combustion chambers, and the turbine, and a study of the over-all engine performance are reported. Engine performance data obtained at sea-level static conditions could be used to predict static performance at altitudes up to 35,000 feet by use of the standard generalized parameters.
Imaging Performance Analysis of Simbol-X with Simulations
NASA Astrophysics Data System (ADS)
Chauvin, M.; Roques, J. P.
2009-05-01
Simbol-X is an X-Ray telescope operating in formation flight. It means that its optical performances will strongly depend on the drift of the two spacecrafts and its ability to measure these drifts for image reconstruction. We built a dynamical ray tracing code to study the impact of these parameters on the optical performance of Simbol-X (see Chauvin et al., these proceedings). Using the simulation tool we have developed, we have conducted detailed analyses of the impact of different parameters on the imaging performance of the Simbol-X telescope.
Quintana, Daniel S.
2015-01-01
Meta-analysis synthesizes a body of research investigating a common research question. Outcomes from meta-analyses provide a more objective and transparent summary of a research area than traditional narrative reviews. Moreover, they are often used to support research grant applications, guide clinical practice, and direct health policy. The aim of this article is to provide a practical and non-technical guide for psychological scientists that outlines the steps involved in planning and performing a meta-analysis of correlational datasets. I provide a supplementary R script to demonstrate each analytical step described in the paper, which is readily adaptable for researchers to use for their analyses. While the worked example is the analysis of a correlational dataset, the general meta-analytic process described in this paper is applicable for all types of effect sizes. I also emphasize the importance of meta-analysis protocols and pre-registration to improve transparency and help avoid unintended duplication. An improved understanding this tool will not only help scientists to conduct their own meta-analyses but also improve their evaluation of published meta-analyses. PMID:26500598
Quintana, Daniel S
2015-01-01
Meta-analysis synthesizes a body of research investigating a common research question. Outcomes from meta-analyses provide a more objective and transparent summary of a research area than traditional narrative reviews. Moreover, they are often used to support research grant applications, guide clinical practice, and direct health policy. The aim of this article is to provide a practical and non-technical guide for psychological scientists that outlines the steps involved in planning and performing a meta-analysis of correlational datasets. I provide a supplementary R script to demonstrate each analytical step described in the paper, which is readily adaptable for researchers to use for their analyses. While the worked example is the analysis of a correlational dataset, the general meta-analytic process described in this paper is applicable for all types of effect sizes. I also emphasize the importance of meta-analysis protocols and pre-registration to improve transparency and help avoid unintended duplication. An improved understanding this tool will not only help scientists to conduct their own meta-analyses but also improve their evaluation of published meta-analyses.
NASA Technical Reports Server (NTRS)
VanHeukelem, Laurie; Thomas, Crystal S.; Glibert, Patricia M.
2001-01-01
The need for accurate determination of chlorophyll a (chl a) is of interest for numerous reasons. From the need for ground-truth data for remote sensing to pigment detection for laboratory experimentation, it is essential to know the accuracy of the analyses and the factors potentially contributing to variability and error. Numerous methods and instrument techniques are currently employed in the analyses of chl a. These methods range from spectrophotometric quantification, to fluorometric analysis and determination by high performance liquid chromatography. Even within the application of HPLC techniques, methods vary. Here we provide the results of a comparison among methods and provide some guidance for improving the accuracy of these analyses. These results are based on a round-robin conducted among numerous investigators, including several in the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) and HyCODE Programs. Our purpose here is not to present the full results of the laboratory intercalibration; those results will be presented elsewhere. Rather, here we highlight some of the major factors that may contribute to the variability observed. Specifically, we aim to assess the comparability of chl a analyses performed by fluorometry and HPLC, and we identify several factors in the analyses which may contribute disproportionately to this variability.
Creatine Supplementation and Lower Limb Strength Performance: A Systematic Review and Meta-Analyses.
Lanhers, Charlotte; Pereira, Bruno; Naughton, Geraldine; Trousselard, Marion; Lesage, François-Xavier; Dutheil, Frédéric
2015-09-01
Creatine is the most widely used supplementation to increase strength performance. However, the few meta-analyses are more than 10 years old and suffer from inclusion bias such as the absence of randomization and placebo, the diversity of the inclusion criteria (aerobic/endurance, anaerobic/strength), no evaluation on specific muscles or group of muscles, and the considerable amount of conflicting results within the last decade. The objective of this systematic review was to evaluate meta-analyzed effects of creatine supplementation on lower limb strength performance. We conducted a systematic review and meta-analyses of all randomized controlled trials comparing creatine supplementation with a placebo, with strength performance of the lower limbs measured in exercises lasting less than 3 min. The search strategy used the keywords "creatine supplementation" and "performance". Dependent variables were creatine loading, total dose, duration, the time-intervals between baseline (T0) and the end of the supplementation (T1), as well as any training during supplementation. Independent variables were age, sex, and level of physical activity at baseline. We conducted meta-analyses at T1, and on changes between T0 and T1. Each meta-analysis was stratified within lower limb muscle groups and exercise tests. We included 60 studies (646 individuals in the creatine supplementation group and 651 controls). At T1, the effect size (ES) among stratification for squat and leg press were, respectively, 0.336 (95 % CI 0.047-0.625, p = 0.023) and 0.297 (95 % CI 0.098-0.496, p = 0.003). Overall quadriceps ES was 0.266 (95 % CI 0.150-0.381, p < 0.001). Global lower limb ES was 0.235 (95 % CI 0.125-0.346, p < 0.001). Meta-analysis on changes between T0 and T1 gave similar results. The meta-regression showed no links with characteristics of population or of supplementation, demonstrating the creatine efficacy effects, independent of all listed conditions. Creatine supplementation is effective in lower limb strength performance for exercise with a duration of less than 3 min, independent of population characteristic, training protocols, and supplementary doses and duration.
Aerocapture Performance Analysis of A Venus Exploration Mission
NASA Technical Reports Server (NTRS)
Starr, Brett R.; Westhelle, Carlos H.
2005-01-01
A performance analysis of a Discovery Class Venus Exploration Mission in which aerocapture is used to capture a spacecraft into a 300km polar orbit for a two year science mission has been conducted to quantify its performance. A preliminary performance assessment determined that a high heritage 70 sphere-cone rigid aeroshell with a 0.25 lift to drag ratio has adequate control authority to provide an entry flight path angle corridor large enough for the mission s aerocapture maneuver. A 114 kilograms per square meter ballistic coefficient reference vehicle was developed from the science requirements and the preliminary assessment s heating indicators and deceleration loads. Performance analyses were conducted for the reference vehicle and for sensitivity studies on vehicle ballistic coefficient and maximum bank rate. The performance analyses used a high fidelity flight simulation within a Monte Carlo executive to define the aerocapture heating environment and deceleration loads and to determine mission success statistics. The simulation utilized the Program to Optimize Simulated Trajectories (POST) that was modified to include Venus specific atmospheric and planet models, aerodynamic characteristics, and interplanetary trajectory models. In addition to Venus specific models, an autonomous guidance system, HYPAS, and a pseudo flight controller were incorporated in the simulation. The Monte Carlo analyses incorporated a reference set of approach trajectory delivery errors, aerodynamic uncertainties, and atmospheric density variations. The reference performance analysis determined the reference vehicle achieves 100% successful capture and has a 99.87% probability of attaining the science orbit with a 90 meters per second delta V budget for post aerocapture orbital adjustments. A ballistic coefficient trade study conducted with reference uncertainties determined that the 0.25 L/D vehicle can achieve 100% successful capture with a ballistic coefficient of 228 kilograms per square meter and that the increased ballistic coefficient increases post aerocapture V budget to 134 meters per second for a 99.87% probability of attaining the science orbit. A trade study on vehicle bank rate determined that the 0.25 L/D vehicle can achieve 100% successful capture when the maximum bank rate is decreased from 30 deg/s to 20 deg/s. The decreased bank rate increases post aerocapture delta V budget to 102 meters per second for a 99.87% probability of attaining the science orbit.
Exploring Reading Comprehension Skill Relationships through the G-DINA Model
ERIC Educational Resources Information Center
Chen, Huilin; Chen, Jinsong
2016-01-01
By analysing the test data of 1029 British secondary school students' performance on 20 Programme for International Student Assessment English reading items through the generalised deterministic input, noisy "and" gate (G-DINA) model, the study conducted two investigations on exploring the relationships among the five reading…
Efficiency Analysis of Public Universities in Thailand
ERIC Educational Resources Information Center
Kantabutra, Saranya; Tang, John C. S.
2010-01-01
This paper examines the performance of Thai public universities in terms of efficiency, using a non-parametric approach called data envelopment analysis. Two efficiency models, the teaching efficiency model and the research efficiency model, are developed and the analysis is conducted at the faculty level. Further statistical analyses are also…
CatReg Software for Categorical Regression Analysis (Jul 2012)
CatReg is a computer program, written in the R (http://cran.r-project.org) programming language, to support the conduct of exposure-response analyses by toxicologists and health scientists. CatReg can be used to perform categorical regressi...
CatReg Software for Categorical Regression Analysis (Nov 2006)
CatReg is a computer program, written in the R (http://cran.r-project.org) programming language, to support the conduct of exposure-response analyses by toxicologists and health scientists. CatReg can be used to perform categorical regressi...
CatReg Software for Categorical Regression Analysis (Feb 2011)
CatReg is a computer program, written in the R (http://cran.r-project.org) programming language, to support the conduct of exposure-response analyses by toxicologists and health scientists. CatReg can be used to perform categorical regressi...
Managing Instructor Training to Achieve Excellence.
ERIC Educational Resources Information Center
Norton, Robert E.
A group of concerned companies in the nuclear electric power industry formed the Electric Utility Instructor Training Consortium to train instructors in a cost-effective and time-efficient manner. The companies collaborated with the Ohio State University to (1) conduct job and task analyses; (2) develop performance-based instructor modules; (3)…
Accident Avoidance Skill Training and Performance Testing. Final Report.
ERIC Educational Resources Information Center
Hatterick, G. Richard; Barthurst, James R.
A two-phased study was conducted to determine the feasibility of training drivers to acquire skills needed to avoid critical conflict motor vehicle accidents, and to develop the procedures and materials necessary for such training. Basic data were derived from indepth accident investigations and task analyses of driver behavior. Principal…
The FAA's Approach to Quality Assurance in the Flight Safety Analysis of Launch and Reentry Vehicles
NASA Astrophysics Data System (ADS)
Murray, Daniel P.; Weil, Andre
2010-09-01
The U.S. Federal Aviation Administration(FAA) Office of Commercial Space Transportation’s safety mission is to ensure protection of the public, property, and the national security and foreign policy interests of the United States during commercial launch and reentry activities. As part of this mission, the FAA issues licenses to the operators of launch and reentry vehicles who successfully demonstrate compliance with FAA regulations. To meet these regulations, vehicle operators submit an application that contains, among other things, flight safety analyses of their proposed missions. In the process of evaluating these submitted analyses, the FAA often conducts its own independent analyses, using input data from the submitted license application. These analyses are conducted according to approved procedures using industry developed tools. To assist in achieving the highest levels of quality in these independent analyses, the FAA has developed a quality assurance program that consists of multiple levels of review. These reviews rely on the work of multiple teams, as well as additional, independently performed work of support contractors. This paper describes the FAA’s quality assurance process for flight safety analyses. Members of the commercial space industry may find that elements of this process can be easily applied to their own analyses, improving the quality of the material they submit to the FAA in their license applications.
Girman, Cynthia J; Faries, Douglas; Ryan, Patrick; Rotelli, Matt; Belger, Mark; Binkowitz, Bruce; O'Neill, Robert
2014-05-01
The use of healthcare databases for comparative effectiveness research (CER) is increasing exponentially despite its challenges. Researchers must understand their data source and whether outcomes, exposures and confounding factors are captured sufficiently to address the research question. They must also assess whether bias and confounding can be adequately minimized. Many study design characteristics may impact on the results; however, minimal if any sensitivity analyses are typically conducted, and those performed are post hoc. We propose pre-study steps for CER feasibility assessment and to identify sensitivity analyses that might be most important to pre-specify to help ensure that CER produces valid interpretable results.
Analysis of a Hybrid Wing Body Center Section Test Article
NASA Technical Reports Server (NTRS)
Wu, Hsi-Yung T.; Shaw, Peter; Przekop, Adam
2013-01-01
The hybrid wing body center section test article is an all-composite structure made of crown, floor, keel, bulkhead, and rib panels utilizing the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) design concept. The primary goal of this test article is to prove that PRSEUS components are capable of carrying combined loads that are representative of a hybrid wing body pressure cabin design regime. This paper summarizes the analytical approach, analysis results, and failure predictions of the test article. A global finite element model of composite panels, metallic fittings, mechanical fasteners, and the Combined Loads Test System (COLTS) test fixture was used to conduct linear structural strength and stability analyses to validate the specimen under the most critical combination of bending and pressure loading conditions found in the hybrid wing body pressure cabin. Local detail analyses were also performed at locations with high stress concentrations, at Tee-cap noodle interfaces with surrounding laminates, and at fastener locations with high bearing/bypass loads. Failure predictions for different composite and metallic failure modes were made, and nonlinear analyses were also performed to study the structural response of the test article under combined bending and pressure loading. This large-scale specimen test will be conducted at the COLTS facility at the NASA Langley Research Center.
Gaete, Jorge; Montero-Marin, Jesus; Rojas-Barahona, Cristian A.; Olivares, Esterbina; Araya, Ricardo
2016-01-01
School membership appears to be an important factor in explaining the relationship between students and schools, including school staff. School membership is associated with several school-related outcomes, such as academic performance and expectations. Most studies on school membership have been conducted in developed countries. The Psychological Sense of School Membership (PSSM) scale (18 items: 13 positively worded items, 5 negatively worded items) has been widely used to measure this construct, but no studies regarding its validity and reliability have been conducted in Spanish-speaking Latin American countries. This study investigates the psychometric properties, factor structure and reliability of this scale in a sample of 1250 early adolescents in Chile. Both exploratory and confirmatory factor analyses provide evidence of an excellent fit for a one-factor solution after removing the negatively worded items. The internal consistency of this new abbreviated version was 0.92. The association analyses demonstrated that high school membership was associated with better academic performance, stronger school bonding, a reduced likelihood of school misbehavior, and reduced likelihood of substance use. Analyses showed support for the reliability and validity of the PSSM among Chilean adolescents. PMID:27999554
Arsenic levels in drinking water and mortality of liver cancer in Taiwan.
Lin, Hung-Jung; Sung, Tzu-I; Chen, Chi-Yi; Guo, How-Ran
2013-11-15
The carcinogenic effect of arsenic is well documented, but epidemiologic data on liver cancer were limited. To evaluate the dose-response relationship between arsenic in drinking water and mortality of liver cancer, we conducted a study in 138 villages in the southwest coast area of Taiwan. We assessed arsenic levels in drinking water using data from a survey conducted by the government and reviewed death certificates from 1971 to 1990 to identify liver cancer cases. Using village as the unit, we conducted multi-variate regression analyses and then performed post hoc analyses to validate the findings. During the 20-year period, 802 male and 301 female mortality cases of liver cancer were identified. After adjusting for age, arsenic levels above 0.64 mg/L were associated with an increase in the liver cancer mortality in both genders, but no significant effect was observed for lower exposure categories. Post hoc analyses and a review of literature supported these findings. We concluded that exposures to high arsenic levels in drinking water are associated with the occurrence of liver cancer, but such an effect is not prominent at exposure levels lower than 0.64 mg/L. Copyright © 2013 Elsevier B.V. All rights reserved.
A Measure of Team Resilience: Developing the Resilience at Work Team Scale.
McEwen, Kathryn; Boyd, Carolyn M
2018-03-01
This study develops, and initial evaluates, a new measure of team-based resilience for use in research and practice. We conducted preliminary analyses, based on a cross-sectional sample of 344 employees nested within 31 teams. Seven dimensions were identified through exploratory and confirmatory factor analyses. The measure had high reliability and significant discrimination to indicate the presence of a unique team-based aspect of resilience that contributed to higher work engagement and higher self-rated team performance, over and above the effects of individual resilience. Multilevel analyses showed that team, but not individual, resilience predicted self-rated team performance. Practice implications include a need to focus on collective as well as individual behaviors in resilience-building. The measure provides a diagnostic instrument for teams and a scale to evaluate organizational interventions and research the relationship of resilience to other constructs.
Star 48 solid rocket motor nozzle analyses and instrumented firings
NASA Technical Reports Server (NTRS)
Porter, R. L.
1986-01-01
The analyses and testing performed by NASA in support of an expanded and improved nozzle design data base for use by the U.S. solid rocket motor industry is presented. A production nozzle with a history of one ground failure and two flight failures was selected for analyses and testing. The stress analysis was performed with the Champion computer code developed by the U.S. Navy. Several improvements were made to the code. Strain predictions were made and compared to test data. Two short duration motor firings were conducted with highly instrumented nozzles. The first nozzle had 58 thermocouples, 66 strain gages, and 8 bondline pressure measurements. The second nozzle had 59 thermocouples, 68 strain measurements, and 8 bondline pressure measurements. Most of this instrumentation was on the nonmetallic parts, and provided significantly more thermal and strain data on the nonmetallic components of a nozzle than has been accumulated in a solid rocket motor test to date.
Trust and team performance: A meta-analysis of main effects, moderators, and covariates.
De Jong, Bart A; Dirks, Kurt T; Gillespie, Nicole
2016-08-01
Cumulating evidence from 112 independent studies (N = 7,763 teams), we meta-analytically examine the fundamental questions of whether intrateam trust is positively related to team performance, and the conditions under which it is particularly important. We address these questions by analyzing the overall trust-performance relationship, assessing the robustness of this relationship by controlling for other relevant predictors and covariates, and examining how the strength of this relationship varies as a function of several moderating factors. Our findings confirm that intrateam trust is positively related to team performance, and has an above-average impact (ρ = .30). The covariate analyses show that this relationship holds after controlling for team trust in leader and past team performance, and across dimensions of trust (i.e., cognitive and affective). The moderator analyses indicate that the trust-performance relationship is contingent upon the level of task interdependence, authority differentiation, and skill differentiation in teams. Finally, we conducted preliminary analyses on several emerging issues in the literature regarding the conceptualization and measurement of trust and team performance (i.e., referent of intrateam trust, dimension of performance, performance objectivity). Together, our findings contribute to the literature by helping to (a) integrate the field of intrateam trust research, (b) resolve mixed findings regarding the trust-performance relationship, (c) overcome scholarly skepticism regarding the main effect of trust on team performance, and (d) identify the conditions under which trust is most important for team performance. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Comprehensive neurocognitive assessment of patients with anorexia nervosa.
Phillipou, Andrea; Gurvich, Caroline; Castle, David Jonathan; Abel, Larry Allen; Rossell, Susan Lee
2015-12-22
To utilise a comprehensive cognitive battery to gain a better understanding of cognitive performance in anorexia nervosa (AN). Twenty-six individuals with AN and 27 healthy control participants matched for age, gender and premorbid intelligence, participated in the study. A standard cognitive battery, the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery, was used to investigate performance on seven cognitive domains with the use of 10 different tasks: speed of processing [Brief Assessment Of Cognition In Schizophrenia: Symbol Coding, Category Fluency: Animal Naming (Fluency) and Trail Making Test: Part A], attention/vigilance [Continuous Performance Test - Identical Pairs (CPT-IP)], working memory [Wechsler Memory Scale (WMS(®)-III): Spatial Span, and Letter-Number Span (LNS)], verbal learning [Hopkins Verbal Learning Test - Revised], visual learning [Brief Visuospatial Memory Test - Revised], reasoning and problem solving [Neuropsychological Assessment Battery: Mazes], and social cognition [Mayer-Salovey-Caruso Emotional Intelligence Test: Managing Emotions]. Statistical analyses involved the use of multivariate and univariate analyses of variance. Analyses conducted on the cognitive domain scores revealed no overall significant difference between groups nor any interaction between group and domain score [F(1,45) = 0.73, P = 0.649]. Analyses conducted on each of the specific tasks within the cognitive domains revealed significantly slower reaction times for false alarm responses on the CPT-IP task in AN [F(1,51) = 12.80, P < 0.01, Cohen's d = 0.982] and a trend towards poorer performance in AN on the backward component of the WMS(®)-III Spatial Span task [F(1,51) = 5.88, P = 0.02, Cohen's d = -0.665]. The finding of slower reaction times of false alarm responses is, however, limited due to the small number of false alarm responses for either group. The findings are discussed in terms of poorer capacity to manipulate and process visuospatial material in AN.
Buckling Design and Analysis of a Payload Fairing One-Sixth Cylindrical Arc-Segment Panel
NASA Technical Reports Server (NTRS)
Kosareo, Daniel N.; Oliver, Stanley T.; Bednarcyk, Brett A.
2013-01-01
Design and analysis results are reported for a panel that is a 16th arc-segment of a full 33-ft diameter cylindrical barrel section of a payload fairing structure. Six such panels could be used to construct the fairing barrel, and, as such, compression buckling testing of a 16th arc-segment panel would serve as a validation test of the buckling analyses used to design the fairing panels. In this report, linear and nonlinear buckling analyses have been performed using finite element software for 16th arc-segment panels composed of aluminum honeycomb core with graphiteepoxy composite facesheets and an alternative fiber reinforced foam (FRF) composite sandwich design. The cross sections of both concepts were sized to represent realistic Space Launch Systems (SLS) Payload Fairing panels. Based on shell-based linear buckling analyses, smaller, more manageable buckling test panel dimensions were determined such that the panel would still be expected to buckle with a circumferential (as opposed to column-like) mode with significant separation between the first and second buckling modes. More detailed nonlinear buckling analyses were then conducted for honeycomb panels of various sizes using both Abaqus and ANSYS finite element codes, and for the smaller size panel, a solid-based finite element analysis was conducted. Finally, for the smaller size FRF panel, nonlinear buckling analysis was performed wherein geometric imperfections measured from an actual manufactured FRF were included. It was found that the measured imperfection did not significantly affect the panel's predicted buckling response
2016-11-18
researchers from the U.S. Army Research Institute of Environmental Medicine (USARIEM) designed and conducted a total of three web - administered job...USARIEM) and Human Performance Systems, Inc. designed three web -administered job analyses questionnaires JAQs to be completed by Army cavalry scouts and...responses from Soldiers in many Army MOSs. This may have affected the quality of some item responses. 3) This survey was web -administered, and
Low-thrust chemical propulsion system pump technology
NASA Technical Reports Server (NTRS)
Meadville, J. W.
1980-01-01
A study was conducted within the thrust range 450 to 9000 N (100 to 2000 pounds). Performance analyses were made on centrifugal, pitot, Barske, drag, Tesla, gear, piston, lobe, and vane pumps with liquid hydrogen, liquid methane, and liquid oxygen as propellants. Gaseous methane and hydrogen driven axial impulse turbines, vane expanders, piston expanders, and electric motors were studied as drivers. Data are presented on performance, sizes, weights, and estimated service lives and costs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cooke, Gary A.; Pestovich, John A.; Huber, Heinz J.
This report presents the results for solid phase characterization (SPC) of solid samples removed from tank 241-C-108 (C-108) on August 12-13,2012, using the off-riser sampler. Samples were received at the 222-S Laboratory on August 13 and were described and photographed. The SPC analyses that were performed include scanning electron microscopy (SEM) using the ASPEX(R)l scanning electron microscope, X-ray diffraction (XRD) using the Rigaku(R) 2 MiniFlex X-ray diffractometer, and polarized light microscopy (PLM) using the Nikon(R) 3 Eclipse Pol optical microscope. The SEM is equipped with an energy dispersive X-ray spectrometer (EDS) to provide chemical information. Gary A. Cooke conducted themore » SEM analysis, John A. Pestovich performed the XRD analysis, and Dr. Heinz J. Huber performed the PLM examination. The results of these analyses are presented here.« less
Discussion of Source Reconstruction Models Using 3D MCG Data
NASA Astrophysics Data System (ADS)
Melis, Massimo De; Uchikawa, Yoshinori
In this study we performed the source reconstruction of magnetocardiographic signals generated by the human heart activity to localize the site of origin of the heart activation. The localizations were performed in a four compartment model of the human volume conductor. The analyses were conducted on normal subjects and on a subject affected by the Wolff-Parkinson-White syndrome. Different models of the source activation were used to evaluate whether a general model of the current source can be applied in the study of the cardiac inverse problem. The data analyses were repeated using normal and vector component data of the MCG. The results show that a distributed source model has the better accuracy in performing the source reconstructions, and that 3D MCG data allow finding smaller differences between the different source models.
NASA Astrophysics Data System (ADS)
Fontana, S.; Amendola, R.; Chevalier, S.; Piccardo, P.; Caboche, G.; Viviani, M.; Molins, R.; Sennour, M.
One of challenges in improving the performance and cost-effectiveness of solid oxide fuel cells (SOFCs) is the development of suitable interconnect materials. Recent researches have enabled to decrease the operating temperature of the SOFC from 1000 to 800 °C. Chromia forming alloys are then among the best candidates for interconnects. However, low electronic conductivity and volatility of chromium oxide scale need to be solved to improve interconnect performances. In the field of high temperature oxidation of metals, it is well known that the addition of reactive element into alloys or as thin film coatings, improves their oxidation resistance at high temperature. The elements of beginning of the lanthanide group and yttrium are the most efficient. The goal of this study is to make reactive element oxides (La 2O 3, Nd 2O 3 and Y 2O 3) coatings by metal organic chemical vapour deposition (MOCVD) on Crofer 22 APU, AL 453 and Haynes 230 in order to form perovskite oxides which present a good conductivity at high temperature. The coatings were analysed after 100 h ageing at 800 °C in air under atmospheric pressure by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analyses, X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses. Area-specific resistance (ASR) was measured in air for the same times and temperature, using a sandwich technique with Pt paste for electrical contacts between surfaces. The ASR values for the best coating were estimated to be limited to 0.035 Ω cm 2, even after 40,000 h use.
NASA Astrophysics Data System (ADS)
Bowling, Shannon Raye
The aircraft maintenance industry is a complex system consisting of human and machine components, because of this; much emphasis has been placed on improving aircraft-inspection performance. One proven technique for improving inspection performance is the use of training. There are several strategies that have been implemented for training, one of which is feedforward information. The use of prior information (feedforward) is known to positively affect inspection performance. This information can consist of knowledge about defect characteristics (types, severity/criticality, and location) and the probability of occurrence. Although several studies have been conducted that demonstrate the usefulness of feedforward as a training strategy, there are certain research issues that need to be addressed. This study evaluates the effect of feedforward information in a simulated 3-dimensional environment by the use of virtual reality. A controlled study was conducted to evaluate the effectiveness of feedforward information in a simulated aircraft inspection environment. The study was conducted in two phases. The first phase evaluated the difference between general and detailed inspection at different pacing levels. The second phase evaluated the effect of feedforward information pertaining to severity, probability and location. Analyses of the results showed that subjects performing detailed inspection performed significantly better than while performing general inspection. Pacing also had the effect of reducing performance for both general and detailed inspection. The study also found that as the level of feedforward information increases, performance also increases. In addition to evaluating performance measures, the study also evaluated process and subjective measures. It was found that process measures such as number of fixation points, fixation groups, mean fixation duration, and percent area covered were all affected by the treatment levels. Analyses of the subjective measures also found a correlation between the perceived usefulness of feedforward information and the actual effect on performance. The study also examined the potential of virtual reality as a training tool and analyzed the effect different calculational algorithms have on determining various process measures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clauss, D.B.
A 1:6-scale model of a reinforced concrete containment building was pressurized incrementally to failure at a remote site at Sandia National Laboratories. The response of the model was recorded with more than 1000 channels of data (primarily strain and displacement measurements) at 37 discrete pressure levels. The primary objective of this test was to generate data that could be used to validate methods for predicting the performance of containment buildings subject to loads beyond their design basis. Extensive analyses were conducted before the test to predict the behavior of the model. Ten organizations in Europe and the US conducted independentmore » analyses of the model and contributed to a report on the pretest predictions. Predictions included structural response at certain predetermined locations in the model as well as capacity and failure mode. This report discusses comparisons between the pretest predictions and the experimental results. Posttest evaluations that were conducted to provide additional insight into the model behavior are also described. The significance of the analysis and testing of the 1:6-scale model to performance evaluations of actual containments subject to beyond design basis loads is also discussed. 70 refs., 428 figs., 24 tabs.« less
Thermal Characterization for a Modular 3-D Multichip Module
NASA Technical Reports Server (NTRS)
Fan, Mark S.; Plante, Jeannette; Shaw, Harry
2000-01-01
NASA Goddard Space Flight Center has designed a high-density modular 3-D multichip module (MCM) for future spaceflight use. This MCM features a complete modular structure, i.e., each stack can be removed from the package without damaging the structure. The interconnection to the PCB is through the Column Grid Array (CGA) technology. Because of its high-density nature, large power dissipation from multiple layers of circuitry is anticipated and CVD diamond films are used in the assembly for heat conduction enhancement. Since each stacked layer dissipates certain amount of heat, designing effective heat conduction paths through each stack and balancing the heat dissipation within each stack for optimal thermal performance become a challenging task. To effectively remove the dissipated heat from the package, extensive thermal analysis has been performed with finite element methods. Through these analyses, we are able to improve the thermal design and increase the total wattage of the package for maximum electrical performance. This paper provides details on the design-oriented thermal analysis and performance enhancement. It also addresses issues relating to contact thermal resistance between the diamond film and the metallic heat conduction paths.
Full-Scale Crash Tests and Analyses of Three High-Wing Single
NASA Technical Reports Server (NTRS)
Annett, Martin S.; Littell, Justin D.; Stimson, Chad M.; Jackson, Karen E.; Mason, Brian H.
2015-01-01
The NASA Emergency Locator Transmitter Survivability and Reliability (ELTSAR) project was initiated in 2014 to assess the crash performance standards for the next generation of ELT systems. Three Cessna 172 aircraft have been acquired to conduct crash testing at NASA Langley Research Center's Landing and Impact Research Facility. Testing is scheduled for the summer of 2015 and will simulate three crash conditions; a flare to stall while emergency landing, and two controlled flight into terrain scenarios. Instrumentation and video coverage, both onboard and external, will also provide valuable data of airframe response. Full-scale finite element analyses will be performed using two separate commercial explicit solvers. Calibration and validation of the models will be based on the airframe response under these varying crash conditions.
Disk flexibility effects on the rotordynamics of the SSME high pressure turbopumps
NASA Technical Reports Server (NTRS)
Flowers, George T.
1990-01-01
Rotordynamical analyses are typically performed using rigid disk models. Studies of rotor models in which the effects of disk flexibility were included indicate that it may be an important effect for many systems. This issue is addressed with respect to the Space Shuttle Main Engine high pressure turbopumps. Finite element analyses were performed for a simplified free-free flexible disk rotor models and the modes and frequencies compared to those of a rigid disk model. Equations were developed to account for disk flexibility in rotordynamical analysis. Simulation studies were conducted to assess the influence of disk flexibility on the HPOTP. Some recommendations are given as to the importance of disk flexibility and for how this project should proceed.
A systematic review of the association between family meals and adolescent risk outcomes.
Goldfarb, Samantha S; Tarver, Will L; Locher, Julie L; Preskitt, Julie; Sen, Bisakha
2015-10-01
To conduct a systematic review of the literature examining the relationship between family meals and adolescent health risk outcomes. We performed a systematic search of original empirical studies published between January 1990 and September 2013. Based on data from selected studies, we conducted logistic regression models to examine the correlates of reporting a protective association between frequent family meals and adolescent outcomes. Of the 254 analyses from 26 selected studies, most reported a significant association between family meals and the adolescent risk outcome-of-interest. However, model analyses which controlled for family connectedness variables, or used advanced empirical methods to account for family-level confounders, were less likely than unadjusted models to report significant relationships. The type of analysis conducted was significantly associated with the likelihood of finding a protective relationship between family meals and the adolescent outcome-of-interest, yet very few studies are using such methods in the literature. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Disentangling the Effects of Student Attitudes and Behaviors on Academic Performance
ERIC Educational Resources Information Center
Janssen, Susan; O'Brien, Maureen
2014-01-01
The interplay among motivation, ability, attitudes, behaviors, homework, and learning is unclear from previous research. We analyze data collected from 687 students enrolled in seven economics courses. A model explaining homework and exam scores is estimated, and separate analyses of ability and motivation groups are conducted. We find that…
Development and Validation of a Mathematics Anxiety Scale for Students
ERIC Educational Resources Information Center
Ko, Ho Kyoung; Yi, Hyun Sook
2011-01-01
This study developed and validated a Mathematics Anxiety Scale for Students (MASS) that can be used to measure the level of mathematics anxiety that students experience in school settings and help them overcome anxiety and perform better in mathematics achievement. We conducted a series of preliminary analyses and panel reviews to evaluate quality…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-17
... Agency, Research Triangle Park, North Carolina 27711; telephone number: (919) 541-5515; fax number: (919... for the EPA's regulations in title 40 of the CFR, after appearing in the Federal Register when... applicant must conduct the necessary research, perform the appropriate analyses and prepare the permit...
ERIC Educational Resources Information Center
Castejón, Alba; Zancajo, Adrián
2015-01-01
This article focuses on analysing the effect of educational differentiation policies of OECD educational systems on socioeconomically disadvantaged students, based on data from PISA 2009. The analysis is conducted on the basis of a definition of two subgroups of disadvantaged students: those that achieve high scores, and those obtaining scores…
Do They Know Their ABCs? Letter-Name Knowledge of Urban Preschoolers
ERIC Educational Resources Information Center
Edwards, Liesl
2012-01-01
This study analyzed the performance and growth in letter knowledge and letter identification skills of children across an academic year. Repeated measures analyses of variance were conducted on letter name knowledge measures administered at three time points for all participating children (N = 177) and seven time points for children (n = 106)…
Effect of Purification Procedures on DIF Analysis in IRTPRO
ERIC Educational Resources Information Center
Fikis, David R. J.; Oshima, T. C.
2017-01-01
Purification of the test has been a well-accepted procedure in enhancing the performance of tests for differential item functioning (DIF). As defined by Lord, purification requires reestimation of ability parameters after removing DIF items before conducting the final DIF analysis. IRTPRO 3 is a recently updated program for analyses in item…
The Impact of Teasing and Bullying on Schoolwide Academic Performance
ERIC Educational Resources Information Center
Lacey, Anna; Cornell, Dewey
2013-01-01
Hierarchical regression analyses conducted at the school level found that the perceived prevalence of teasing and bullying was predictive of schoolwide passing rates on state-mandated achievement testing used to meet No Child Left Behind requirements. These findings could not be attributed to the proportion of minority students in the school,…
Emotional and Cognitive Effects of Peer Tutoring among Secondary School Mathematics Students
ERIC Educational Resources Information Center
Alegre Ansuategui, Francisco José; Moliner Miravet, Lidón
2017-01-01
This paper describes an experience of same-age peer tutoring conducted with 19 eighth-grade mathematics students in a secondary school in Castellon de la Plana (Spain). Three constructs were analysed before and after launching the program: academic performance, mathematics self-concept and attitude of solidarity. Students' perceptions of the…
Improving Students' Attitudes toward Science Using Instructional Congruence
ERIC Educational Resources Information Center
Zain, Ahmad Nurulazam Md; Samsudin, Mohd Ali; Rohandi, Robertus; Jusoh, Azman
2010-01-01
The objective of this study was to improve students' attitudes toward science using instructional congruence. The study was conducted in Malaysia, in three low-performing secondary schools in the state of Penang. Data collected with an Attitudes in Science instrument were analysed using Rasch modeling. Qualitative data based on the reflections of…
Evaluation of the USDA Northeast Area-wide Tick Control Project by Meta-analysis
USDA-ARS?s Scientific Manuscript database
As part of the Northeast Area-wide Tick Control Project (NEATCP), meta-analyses were performed using pooled data on the extent of tick-vector control achieved through seven concurrent studies, conducted within five states, using USDA ‘4-Poster’ devices to deliver targeted-acaricide to white-tailed d...
The Workplace Literacy System Project (WLS). Final Performance Report.
ERIC Educational Resources Information Center
Poulton, Bruce R.
The Workplace Literacy System Project (WLS) prepared interactive CD-ROM discs containing about 50 hours of instruction and drill in basic skills presented within the context of the textile/apparel manufacturing industry. The project was conducted at a Sara Lee knit products plant in North Carolina. During the project, literacy task analyses were…
NASA Technical Reports Server (NTRS)
Sevart, F. D.; Patel, S. M.
1973-01-01
Testing and evaluation of a stability augmentation system for aircraft flight control were performed. The flutter suppression system and synthesis conducted on a scale model of a supersonic wing for a transport aircraft are discussed. Mechanization and testing of the leading and trailing edge surface actuation systems are described. The ride control system analyses for a 375,000 pound gross weight B-52E aircraft are presented. Analyses of the B-52E aircraft maneuver load control system are included.
Performance Analysis of Multilevel Parallel Applications on Shared Memory Architectures
NASA Technical Reports Server (NTRS)
Jost, Gabriele; Jin, Haoqiang; Labarta, Jesus; Gimenez, Judit; Caubet, Jordi; Biegel, Bryan A. (Technical Monitor)
2002-01-01
In this paper we describe how to apply powerful performance analysis techniques to understand the behavior of multilevel parallel applications. We use the Paraver/OMPItrace performance analysis system for our study. This system consists of two major components: The OMPItrace dynamic instrumentation mechanism, which allows the tracing of processes and threads and the Paraver graphical user interface for inspection and analyses of the generated traces. We describe how to use the system to conduct a detailed comparative study of a benchmark code implemented in five different programming paradigms applicable for shared memory
Orbit Transfer Vehicle (OTV) engine phase A study
NASA Technical Reports Server (NTRS)
Mellish, J. A.
1978-01-01
Requirements for the orbit transfer vehicle engine were examined. Engine performance/weight sensitivities, the effect of a service life of 300 start/shutdown cycles between overalls on the maximum engine operating pressure, and the sensitivity of the engine design point (i.e., thrust chamber pressure and nozzle area ratio) to the performance requirements specified are among the factors studied. Preliminary engine systems analyses were conducted on the stage combustion, expander, and gas generator engine cycles. Hydrogen and oxygen pump discharge pressure requirements are shown for various engine cycles. Performance of the engine cycles is compared.
Aeromechanics Analysis of a Compound Helicopter
NASA Technical Reports Server (NTRS)
Yeo, Hyeonsoo; Johnson, Wayne
2006-01-01
A design and aeromechanics investigation was conducted for a 100,000-lb compound helicopter with a single main rotor, which is to cruise at 250 knots at 4000 ft/95 deg F condition. Performance, stability, and control analyses were conducted with the comprehensive rotorcraft analysis CAMRAD II. Wind tunnel test measurements of the performance of the H-34 and UH-1D rotors at high advance ratio were compared with calculations to assess the accuracy of the analysis for the design of a high speed helicopter. In general, good correlation was obtained with the increase of drag coefficients in the reverse flow region. An assessment of various design parameters (disk loading, blade loading, wing loading) on the performance of the compound helicopter was made. Performance optimization was conducted to find the optimum twist, collective, tip speed, and taper using the comprehensive analysis. Blade twist was an important parameter on the aircraft performance and most of the benefit of slowing the rotor occurred at the initial 20 to 30% reduction of rotor tip speed. No stability issues were observed with the current design and the control derivatives did not change much with speed, but did exhibit significant coupling.
NASA Technical Reports Server (NTRS)
Ziff, Howard L; Rathert, George A; Gadeberg, Burnett L
1953-01-01
Standard air-to-air-gunnery tracking runs were conducted with F-51H, F8F-1, F-86A, and F-86E airplanes equipped with fixed gunsights. The tracking performances were documented over the normal operating range of altitude, Mach number, and normal acceleration factor for each airplane. The sources of error were studied by statistical analyses of the aim wander.
Calculations vs. measurements of remnant dose rates for SNS spent structures
NASA Astrophysics Data System (ADS)
Popova, I. I.; Gallmeier, F. X.; Trotter, S.; Dayton, M.
2018-06-01
Residual dose rate measurements were conducted on target vessel #13 and proton beam window #5 after extraction from their service locations. These measurements were used to verify calculation methods of radionuclide inventory assessment that are typically performed for nuclear waste characterization and transportation of these structures. Neutronics analyses for predicting residual dose rates were carried out using the transport code MCNPX and the transmutation code CINDER90. For transport analyses complex and rigorous geometry model of the structures and their surrounding are applied. The neutronics analyses were carried out using Bertini and CEM high energy physics models for simulating particles interaction. Obtained preliminary calculational results were analysed and compared to the measured dose rates and overall are showing good agreement with in 40% in average.
Structural evaluation of candidate designs for the large space telescope primary mirror
NASA Technical Reports Server (NTRS)
Soosaar, K.; Grin, R.; Furey, M.; Hamilton, J.
1975-01-01
Structural performance analyses were conducted on two candidate designs (Itek and Perkin-Elmer designs) for the large space telescope three-meter mirror. The mirror designs and the finite-element models used in the analyses evaluation are described. The results of the structural analyses for several different types of loading are presented in tabular and graphic forms. Several additional analyses are also reported: the evaluation of a mirror design concept proposed by the Boeing Co., a study of the global effects of local cell plate deflections, and an investigation of the fracture mechanics problems likely to occur with Cervit and ULE. Flexibility matrices were obtained for the Itek and Perkin-Elmer mirrors to be used in active figure control studies. Summary, conclusions, and recommendations are included.
Calculations vs. measurements of remnant dose rates for SNS spent structures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Popova, Irina I.; Gallmeier, Franz X.; Trotter, Steven M.
Residual dose rate measurements were conducted on target vessel #13 and proton beam window #5 after extraction from their service locations. These measurements were used to verify calculation methods of radionuclide inventory assessment that are typically performed for nuclear waste characterization and transportation of these structures. Neutronics analyses for predicting residual dose rates were carried out using the transport code MCNPX and the transmutation code CINDER90. For transport analyses complex and rigorous geometry model of the structures and their surrounding are applied. The neutronics analyses were carried out using Bertini and CEM high energy physics models for simulating particles interaction.more » Obtained preliminary calculational results were analysed and compared to the measured dose rates and overall are showing good agreement with in 40% in average.« less
Godínez-Alvarez, H; Morín, C; Rivera-Aguilar, V
2012-01-01
Information about the effects of biological soil crusts (BSC) on germination, seedling survival and growth of vascular plants is controversial because they can have positive, neutral or negative effects. This controversy may be because most studies conducted until now have just analysed one or two recruitment stages independently. To understand the BSC effects on vascular plants, it is necessary to consider each stage of the recruitment process and synthesise all this information. The goal of this study was twofold. First, we analyse germination, seedling survival and growth of three vascular plants (Agave marmorata, Prosopis laevigata and Neobuxbaumia tetetzo) on BSC (cyanobacteria and mixed crust) from a tropical desert region of south-central México. Second, we synthesise the information to determine the total effect of BSC on plant species performance. We conducted experiments under controlled conditions to evaluate the proportion of germinated seeds, proportion of surviving seedlings and seedling dry weight in BSC and bare soil. Results showed that BSC have different effects on germination, seedling survival and growth of plant species. Plant species performance was qualitatively higher on BSC than bare soil. The highest performance of A. marmorata and P. laevigata was observed on cyanobacteria and mixed crusts, respectively. The highest performance of N. tetetzo was on both crust types. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.
Edwards, Jerri D.; Ruva, Christine L.; O’Brien, Jennifer L.; Haley, Christine B.; Lister, Jennifer J.
2013-01-01
The purpose of these analyses was to examine mediators of the transfer of cognitive speed of processing training to improved everyday functional performance (Edwards, Wadley, Vance, Roenker, & Ball, 2005). Cognitive speed of processing and visual attention (as measured by the Useful Field of View Test; UFOV) were examined as mediators of training transfer. Secondary data analyses were conducted from the Staying Keen in Later Life (SKILL) study, a randomized cohort study including 126 community dwelling adults 63 to 87 years of age. In the SKILL study, participants were randomized to an active control group or cognitive speed of processing training (SOPT), a non-verbal, computerized intervention involving perceptual practice of visual tasks. Prior analyses found significant effects of training as measured by the UFOV and Timed Instrumental Activities of Daily Living (TIADL) Tests. Results from the present analyses indicate that speed of processing for a divided attention task significantly mediated the effect of SOPT on everyday performance (e.g., TIADL) in a multiple mediation model accounting for 91% of the variance. These findings suggest that everyday functional improvements found from SOPT are directly attributable to improved UFOV performance, speed of processing for divided attention in particular. Targeting divided attention in cognitive interventions may be important to positively affect everyday functioning among older adults. PMID:23066808
Characterization and effectiveness of pay-for-performance in ophthalmology: a systematic review.
Herbst, Tim; Emmert, Martin
2017-06-05
To identify, characterize and compare existing pay-for-performance approaches and their impact on the quality of care and efficiency in ophthalmology. A systematic evidence-based review was conducted. English, French and German written literature published between 2000 and 2015 were searched in the following databases: Medline (via PubMed), NCBI web site, Scopus, Web of Knowledge, Econlit and the Cochrane Library. Empirical as well as descriptive articles were included. Controlled clinical trials, meta-analyses, randomized controlled studies as well as observational studies were included as empirical articles. Systematic characterization of identified pay-for-performance approaches (P4P approaches) was conducted according to the "Model for Implementing and Monitoring Incentives for Quality" (MIMIQ). Methodological quality of empirical articles was assessed according to the Critical Appraisal Skills Programme (CASP) checklists. Overall, 13 relevant articles were included. Eleven articles were descriptive and two articles included empirical analyses. Based on these articles, four different pay-for-performance approaches implemented in the United States were identified. With regard to quality and incentive elements, systematic comparison showed numerous differences between P4P approaches. Empirical studies showed isolated cost or quality effects, while a simultaneous examination of these effects was missing. Research results show that experiences with pay-for-performance approaches in ophthalmology are limited. Identified approaches differ with regard to quality and incentive elements restricting comparability. Two empirical studies are insufficient to draw strong conclusions about the effectiveness and efficiency of these approaches.
Molecular characterization of dengue viruses isolated from patients in Central Java, Indonesia.
Kusmintarsih, Endang S; Hayati, Rahma F; Turnip, Oktaviani N; Yohan, Benediktus; Suryaningsih, Suhestri; Pratiknyo, Hery; Denis, Dionisius; Sasmono, R Tedjo
2017-10-19
Dengue is hyper-endemic in Indonesia. Purwokerto city in Central Java province is routinely ravaged by the disease. Despite the endemicity of dengue in this city, there is still no data on the virological aspects of dengue in the city. We conducted a molecular surveillance study of the circulating dengue viruses (DENV) in Purwokerto city to gain information on the virus origin, serotype and genotype distribution, and phylogenetic characteristics of DENV. A cross-sectional dengue molecular surveillance study was conducted in Purwokerto. Sera were collected from dengue-suspected patients attending three hospitals in the city. Diagnosis was performed using dengue NS1 antigen and IgG/IgM antibodies detection. DENV serotyping was performed using Simplexa Dengue real-time RT-PCR. Sequencing was conducted to obtain full-length DENV Envelope (E) gene sequences, which were then used in phylogenetic and genotypic analyses. Patients' clinical and demographic data were collected and analyzed. A total of 105 dengue-suspected patients' sera were collected, in which 80 (76.2%) were positive for IgM and/or IgG, and 57 (54.2%) were confirmed as dengue by NS1 antigen and/or DENV RNA detection using RT-PCR. Serotyping was successful for 47 isolates. All four serotypes circulated in the area with DENV-3 as the predominant serotype. Phylogenetic analyses grouped the isolates into Genotype I for DENV-1, Cosmopolitan genotype for DENV-2, and Genotype I and II for DENV-3 and -4, respectively. The analyses also revealed the close relatedness of Purwokerto isolates to other DENV strains from Indonesia and neighboring countries. We reveal the molecular and virological characteristics of DENV in Purwokerto, Banyumas regency, Central Java. The genotype and phylogenetic analyses indicate the endemicity of the circulating DENV in the city. Our serotype and genotype data provide references for future dengue molecular epidemiology studies and disease management in the region. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
A new statistical method for design and analyses of component tolerance
NASA Astrophysics Data System (ADS)
Movahedi, Mohammad Mehdi; Khounsiavash, Mohsen; Otadi, Mahmood; Mosleh, Maryam
2017-03-01
Tolerancing conducted by design engineers to meet customers' needs is a prerequisite for producing high-quality products. Engineers use handbooks to conduct tolerancing. While use of statistical methods for tolerancing is not something new, engineers often use known distributions, including the normal distribution. Yet, if the statistical distribution of the given variable is unknown, a new statistical method will be employed to design tolerance. In this paper, we use generalized lambda distribution for design and analyses component tolerance. We use percentile method (PM) to estimate the distribution parameters. The findings indicated that, when the distribution of the component data is unknown, the proposed method can be used to expedite the design of component tolerance. Moreover, in the case of assembled sets, more extensive tolerance for each component with the same target performance can be utilized.
Radioactive Waste Management Complex low-level waste radiological performance assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maheras, S.J.; Rood, A.S.; Magnuson, S.O.
This report documents the projected radiological dose impacts associated with the disposal of radioactive low-level waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. This radiological performance assessment was conducted to evaluate compliance with applicable radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the public and the environment. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses were made for both offsitemore » receptors and individuals inadvertently intruding onto the site after closure. In addition, uncertainty and sensitivity analyses were performed. The results of the analyses indicate compliance with established radiological criteria and provide reasonable assurance that public health and safety will be protected.« less
Li, Changwei; Bazzano, Lydia A.L.; Rao, Dabeeru C.; Hixson, James E.; He, Jiang; Gu, Dongfeng; Gu, Charles C.; Shimmin, Lawrence C.; Jaquish, Cashell E.; Schwander, Karen; Liu, De-Pei; Huang, Jianfeng; Lu, Fanghong; Cao, Jie; Chong, Shen; Lu, Xiangfeng; Kelly, Tanika N.
2016-01-01
We conducted a genome-wide linkage scan and positional association study to identify genes and variants influencing blood lipid levels among participants of the Genetic Epidemiology Network of Salt-Sensitivity (GenSalt) study. The GenSalt study was conducted among 1906 participants from 633 Han Chinese families. Lipids were measured from overnight fasting blood samples using standard methods. Multipoint quantitative trait genome-wide linkage scans were performed on the high-density lipoprotein, low-density lipoprotein, and log-transformed triglyceride phenotypes. Using dense panels of single nucleotide polymorphisms (SNPs), single-marker and gene-based association analyses were conducted to follow-up on promising linkage signals. Additive associations between each SNP and lipid phenotypes were tested using mixed linear regression models. Gene-based analyses were performed by combining P-values from single-marker analyses within each gene using the truncated product method (TPM). Significant associations were assessed for replication among 777 Asian participants of the Multi-ethnic Study of Atherosclerosis (MESA). Bonferroni correction was used to adjust for multiple testing. In the GenSalt study, suggestive linkage signals were identified at 2p11.2–2q12.1 [maximum multipoint LOD score (MML) = 2.18 at 2q11.2] and 11q24.3–11q25 (MML = 2.29 at 11q25) for the log-transformed triglyceride phenotype. Follow-up analyses of these two regions revealed gene-based associations of charged multivesicular body protein 3 (CHMP3), ring finger protein 103 (RNF103), AF4/FMR2 family, member 3 (AFF3), and neurotrimin (NTM ) with triglycerides (P = 4 × 10−4, 1.00 × 10−5, 2.00 × 10−5, and 1.00 × 10−7, respectively). Both the AFF3 and NTM triglyceride associations were replicated among MESA study participants (P = 1.00 × 10−7 and 8.00 × 10−5, respectively). Furthermore, NTM explained the linkage signal on chromosome 11. In conclusion, we identified novel genes associated with lipid phenotypes in linkage regions on chromosomes 2 and 11. PMID:25819087
Methods development for total organic carbon accountability
NASA Technical Reports Server (NTRS)
Benson, Brian L.; Kilgore, Melvin V., Jr.
1991-01-01
This report describes the efforts completed during the contract period beginning November 1, 1990 and ending April 30, 1991. Samples of product hygiene and potable water from WRT 3A were supplied by NASA/MSFC prior to contract award on July 24, 1990. Humidity condensate samples were supplied on August 3, 1990. During the course of this contract chemical analyses were performed on these samples to qualitatively determine specific components comprising, the measured organic carbon concentration. In addition, these samples and known standard solutions were used to identify and develop methodology useful to future comprehensive characterization of similar samples. Standard analyses including pH, conductivity, and total organic carbon (TOC) were conducted. Colorimetric and enzyme linked assays for total protein, bile acid, B-hydroxybutyric acid, methylene blue active substances (MBAS), urea nitrogen, ammonia, and glucose were also performed. Gas chromatographic procedures for non-volatile fatty acids and EPA priority pollutants were also performed. Liquid chromatography was used to screen for non-volatile, water soluble compounds not amenable to GC techniques. Methods development efforts were initiated to separate and quantitate certain chemical classes not classically analyzed in water and wastewater samples. These included carbohydrates, organic acids, and amino acids. Finally, efforts were initiated to identify useful concentration techniques to enhance detection limits and recovery of non-volatile, water soluble compounds.
Park, Jung-Keun
2016-12-01
Job hazard analyses were conducted to assess exposure to musculoskeletal disorder (MSD) risk factors in seven workers of three dry-cleaning establishments. In accordance with the Washington State Ergonomics Rule, the analyses were performed in two separate steps: (1) observation and checklist approaches were made to identify a "caution zone job" in the seven workers' pressing operations across the three shops; and (2) detailed posture and motion analyses were undertaken to determine a "MSD hazard" in one worker's operation using a video technique. One "caution zone job" was identified and it was the pressing operation job in which five physical risk factors were found in the pressing operations. The detailed analyses confirmed that one "MSD hazard", i.e., awkward posture in shoulders, was prevalent in the pressing operations of the three dry-cleaning facilities. It would be desirable to reduce MSD risk factors including awkward shoulder posture in the dry-cleaning industry.
Integrated NDE and FEM characterization of composite rotors
NASA Astrophysics Data System (ADS)
Abdul-Aziz, Ali; Baaklini, George Y.; Trudell, Jeffrey J.
2001-08-01
A structural assessment by integrating finite-element methods (FEM) and a nondestructive evaluation (NDE) of two flywheel rotor assemblies is presented. Composite rotor A is pancake like with a solid hub design, and composite rotor B is cylindrical with a hollow hub design. Detailed analyses under combined centrifugal and interference-fit loading are performed. Two- and three-dimensional stress analyses and two-dimensional fracture mechanics analyses are conducted. A comparison of the structural analysis results obtained with those extracted via NDE findings is reported. Contact effects due to press-fit conditions are evaluated. Stress results generated from the finite-element analyses were corroborated with the analytical solution. Cracks due to rotational loading up to 48 000 rpm for rotor A and 34 000 rpm for rotor B were successfully imaged with NDE and predicted with FEM and fracture mechanics analyses. A procedure that extends current structural analysis to a life prediction tool is also defined.
An Integrated NDE and FEM Characterization of Composite Rotors
NASA Technical Reports Server (NTRS)
Abdul-Aziz, Ali; Baaklini, George Y.; Trudell, Jeffrey J.
2000-01-01
A structural assessment by integrating finite-element methods (FEM) and a nondestructive evaluation (NDE) of two flywheel rotor assemblies is presented. Composite rotor A is pancake like with a solid hub design, and composite rotor B is cylindrical with a hollow hub design. Detailed analyses under combined centrifugal and interference-fit loading are performed. Two- and three-dimensional stress analyses and two-dimensional fracture mechanics analyses are conducted. A comparison of the structural analysis results obtained with those extracted via NDE findings is reported. Contact effects due to press-fit conditions are evaluated. Stress results generated from the finite-element analyses were corroborated with the analytical solution. Cracks due to rotational loading up to 49 000 rpm for rotor A and 34 000 rpm for rotor B were successfully imaged with NDE and predicted with FEM and fracture mechanics analyses. A procedure that extends current structural analysis to a life prediction tool is also defined.
Structural Analysis of Composite Flywheels: an Integrated NDE and FEM Approach
NASA Technical Reports Server (NTRS)
Abdul-Aziz, Ali; Baaklini, George; Trudell, Jeffrey
2001-01-01
A structural assessment by integrating finite-element methods (FEM) and a nondestructive evaluation (NDE) of two flywheel rotor assemblies is presented. Composite rotor A is pancake-like with a solid hub design, and composite rotor B is cylindrical with a hollow hub design. Detailed analyses under combined centrifugal and interference-fit loading are performed. Two- and three-dimensional stress analyses and two-dimensional fracture mechanics analyses are conducted. A comparison of the structural analysis results obtained with those extracted via NDE findings is reported. Contact effects due to press-fit conditions are evaluated. Stress results generated from the finite-element analyses were corroborated with the analytical solution. Cracks due to rotational loading up to 48,000 rpm for rotor A and 34,000 rpm for rotor B were successfully imaged with NDE and predicted with FEM and fracture mechanics analyses. A procedure that extends current structural analysis to a life prediction tool is also defined.
Wu, Xin Yin; Du, Xin Jian; Ho, Robin S T; Lee, Clarence C Y; Yip, Benjamin H K; Wong, Martin C S; Wong, Samuel Y S; Chung, Vincent C H
2017-02-01
Methodological quality of meta-analyses on hypertension treatments can affect treatment decision-making. The authors conducted a cross-sectional study to investigate the methodological quality of meta-analyses on hypertension treatments. One hundred and fifty-eight meta-analyses were identified. Overall, methodological quality was unsatisfactory in the following aspects: comprehensive reporting of financial support (1.9%), provision of included and excluded lists of studies (22.8%), inclusion of grey literature (27.2%), and inclusion of protocols (32.9%). The 126 non-Cochrane meta-analyses had poor performance on almost all the methodological items. Non-Cochrane meta-analyses focused on nonpharmacologic treatments were more likely to consider scientific quality of included studies when making conclusions. The 32 Cochrane meta-analyses generally had good methodological quality except for comprehensive reporting of the sources of support. These results highlight the need for cautious interpretation of these meta-analyses, especially among physicians and policy makers when guidelines are formulated. Future meta-analyses should pay attention to improving these methodological aspects. ©2016 Wiley Periodicals, Inc.
Inertial Sensor Based Analysis of Lie-to-Stand Transfers in Younger and Older Adults
Schwickert, Lars; Boos, Ronald; Klenk, Jochen; Bourke, Alan; Becker, Clemens; Zijlstra, Wiebren
2016-01-01
Many older adults lack the capacity to stand up again after a fall. Therefore, to analyse falls it is relevant to understand recovery patterns, including successful and failed attempts to get up from the floor in general. This study analysed different kinematic features of standing up from the floor. We used inertial sensors to describe the kinematics of lie-to-stand transfer patterns of younger and healthy older adults. Fourteen younger (20–50 years of age, 50% men) and 10 healthy older community dwellers (≥60 years; 50% men) conducted four lie-to-stand transfers from different initial lying postures. The analysed temporal, kinematic, and elliptic fitting complexity measures of transfer performance were significantly different between younger and older subjects (i.e., transfer duration, angular velocity (RMS), maximum vertical acceleration, maximum vertical velocity, smoothness, fluency, ellipse width, angle between ellipses). These results show the feasibility and potential of analysing kinematic features to describe the lie-to-stand transfer performance, to help design interventions and detection approaches to prevent long lies after falls. It is possible to describe age-related differences in lie-to-stand transfer performance using inertial sensors. The kinematic analysis remains to be tested on patterns after real-world falls. PMID:27529249
Systematic reviews: guidance relevant for studies of older people
Wilkinson, Tim; Dodds, Richard M.; Ioannidis, John P. A.
2017-01-01
Abstract Systematic reviews and meta-analyses are increasingly common. This article aims to provide guidance for people conducting systematic reviews relevant to the healthcare of older people. An awareness of these issues will also help people reading systematic reviews to determine whether the results will influence their clinical practice. It is essential that systematic reviews are performed by a team which includes the required technical and clinical expertise. Those performing reviews for the first time should ensure they have appropriate training and support. They must be planned and performed in a transparent and methodologically robust way: guidelines are available. The protocol should be written—and if possible published—before starting the review. Geriatricians will be interested in a table of baseline characteristics, which will help to determine if the studied samples or populations are similar to their patients. Reviews of studies of older people should consider how they will manage issues such as different age cut-offs; non-specific presentations; multiple predictors and outcomes; potential biases and confounders. Systematic reviews and meta-analyses may provide evidence to improve older people's care, or determine where new evidence is required. Newer methodologies, such as meta-analyses of individual level data, network meta-analyses and umbrella reviews, and realist synthesis, may improve the reliability and clinical utility of systematic reviews. PMID:28655142
Park, Douglas L; Coates, Scott; Brewer, Vickery A; Garber, Eric A E; Abouzied, Mohamed; Johnson, Kurt; Ritter, Bruce; McKenzie, Deborah
2005-01-01
Performance Tested Method multiple laboratory validations for the detection of peanut protein in 4 different food matrixes were conducted under the auspices of the AOAC Research Institute. In this blind study, 3 commercially available ELISA test kits were validated: Neogen Veratox for Peanut, R-Biopharm RIDASCREEN FAST Peanut, and Tepnel BioKits for Peanut Assay. The food matrixes used were breakfast cereal, cookies, ice cream, and milk chocolate spiked at 0 and 5 ppm peanut. Analyses of the samples were conducted by laboratories representing industry and international and U.S governmental agencies. All 3 commercial test kits successfully identified spiked and peanut-free samples. The validation study required 60 analyses on test samples at the target level 5 microg peanut/g food and 60 analyses at a peanut-free level, which was designed to ensure that the lower 95% confidence limit for the sensitivity and specificity would not be <90%. The probability that a test sample contains an allergen given a prevalence rate of 5% and a positive test result using a single test kit analysis with 95% sensitivity and 95% specificity, which was demonstrated for these test kits, would be 50%. When 2 test kits are run simultaneously on all samples, the probability becomes 95%. It is therefore recommended that all field samples be analyzed with at least 2 of the validated kits.
Hospital survey on patient safety culture: psychometric analysis on a Scottish sample.
Sarac, Cakil; Flin, Rhona; Mearns, Kathryn; Jackson, Jeanette
2011-10-01
To investigate the psychometric properties of the Hospital Survey on Patient Safety Culture on a Scottish NHS data set. The data were collected from 1969 clinical staff (estimated 22% response rate) from one acute hospital from each of seven Scottish Health boards. Using a split-half validation technique, the data were randomly split; an exploratory factor analysis was conducted on the calibration data set, and confirmatory factor analyses were conducted on the validation data set to investigate and check the original US model fit in a Scottish sample. Following the split-half validation technique, exploratory factor analysis results showed a 10-factor optimal measurement model. The confirmatory factor analyses were then performed to compare the model fit of two competing models (10-factor alternative model vs 12-factor original model). An S-B scaled χ(2) square difference test demonstrated that the original 12-factor model performed significantly better in a Scottish sample. Furthermore, reliability analyses of each component yielded satisfactory results. The mean scores on the climate dimensions in the Scottish sample were comparable with those found in other European countries. This study provided evidence that the original 12-factor structure of the Hospital Survey on Patient Safety Culture scale has been replicated in this Scottish sample. Therefore, no modifications are required to the original 12-factor model, which is suggested for use, since it would allow researchers the possibility of cross-national comparisons.
How to write a systematic review.
Harris, Joshua D; Quatman, Carmen E; Manring, M M; Siston, Robert A; Flanigan, David C
2014-11-01
The role of evidence-based medicine in sports medicine and orthopaedic surgery is rapidly growing. Systematic reviews and meta-analyses are also proliferating in the medical literature. To provide the outline necessary for a practitioner to properly understand and/or conduct a systematic review for publication in a sports medicine journal. Review. The steps of a successful systematic review include the following: identification of an unanswered answerable question; explicit definitions of the investigation's participant(s), intervention(s), comparison(s), and outcome(s); utilization of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines and PROSPERO registration; thorough systematic data extraction; and appropriate grading of the evidence and strength of the recommendations. An outline to understand and conduct a systematic review is provided, and the difference between meta-analyses and systematic reviews is described. The steps necessary to perform a systematic review are fully explained, including the study purpose, search methodology, data extraction, reporting of results, identification of bias, and reporting of the study's main findings. Systematic reviews or meta-analyses critically appraise and formally synthesize the best existing evidence to provide a statement of conclusion that answers specific clinical questions. Readers and reviewers, however, must recognize that the quality and strength of recommendations in a review are only as strong as the quality of studies that it analyzes. Thus, great care must be used in the interpretation of bias and extrapolation of the review's findings to translation to clinical practice. Without advanced education on the topic, the reader may follow the steps discussed herein to perform a systematic review. © 2013 The Author(s).
Hasan, Haroon; Muhammed, Taaha; Yu, Jennifer; Taguchi, Kelsi; Samargandi, Osama A; Howard, A Fuchsia; Lo, Andrea C; Olson, Robert; Goddard, Karen
2017-10-01
The objective of our study was to evaluate the methodological quality of systematic reviews and meta-analyses in Radiation Oncology. A systematic literature search was conducted for all eligible systematic reviews and meta-analyses in Radiation Oncology from 1966 to 2015. Methodological characteristics were abstracted from all works that satisfied the inclusion criteria and quality was assessed using the critical appraisal tool, AMSTAR. Regression analyses were performed to determine factors associated with a higher score of quality. Following exclusion based on a priori criteria, 410 studies (157 systematic reviews and 253 meta-analyses) satisfied the inclusion criteria. Meta-analyses were found to be of fair to good quality while systematic reviews were found to be of less than fair quality. Factors associated with higher scores of quality in the multivariable analysis were including primary studies consisting of randomized control trials, performing a meta-analysis, and applying a recommended guideline related to establishing a systematic review protocol and/or reporting. Systematic reviews and meta-analyses may introduce a high risk of bias if applied to inform decision-making based on AMSTAR. We recommend that decision-makers in Radiation Oncology scrutinize the methodological quality of systematic reviews and meta-analyses prior to assessing their utility to inform evidence-based medicine and researchers adhere to methodological standards outlined in validated guidelines when embarking on a systematic review. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Erickson, J. D.; Macdonald, R. B. (Principal Investigator)
1982-01-01
A "quick look" investigation of the initial LANDSAT-4, thematic mapper (TM) scene received from Goddard Space Flight Center was performed to gain early insight into the characteristics of TM data. The initial scene, containing only the first four bands of the seven bands recorded by the TM, was acquired over the Detroit, Michigan, area on July 20, 1982. It yielded abundant information for scientific investigation. A wide variety of studies were conducted to assess all aspects of TM data. They ranged from manual analyses of image products to detect obvious optical, electronic, or mechanical defects to detailed machine analyses of the digital data content for evaluation of spectral separability of vegetative/nonvegetative classes. These studies were applied to several segments extracted from the full scene. No attempt was made to perform end-to-end statistical evaluations. However, the output of these studies do identify a degree of positive performance from the TM and its potential for advancing state-of-the-art crop inventory and condition assessment technology.
Detonation Performance Analyses for Recent Energetic Molecules
NASA Astrophysics Data System (ADS)
Stiel, Leonard; Samuels, Philip; Spangler, Kimberly; Iwaniuk, Daniel; Cornell, Rodger; Baker, Ernest
2017-06-01
Detonation performance analyses were conducted for a number of evolving and potential high explosive materials. The calculations were completed for theoretical maximum densities of the explosives using the Jaguar thermo-chemical equation of state computer programs for performance evaluations and JWL/JWLB equations of state parameterizations. A number of recently synthesized materials were investigated for performance characterizations and comparisons to existing explosives, including TNT, RDX, HMX, and Cl-20. The analytic cylinder model was utilized to establish cylinder and Gurney velocities as functions of the radial expansions of the cylinder for each explosive. The densities and heats of formulation utilized in the calculations are primarily experimental values from Picatinny Arsenal and other sources. Several of the new materials considered were predicted to have enhanced detonation characteristics compared to conventional explosives. In order to confirm the accuracy of the Jaguar and analytic cylinder model results, available experimental detonation and Gurney velocities for representative energetic molecules and their formulations were compared with the corresponding calculated values. Close agreement was obtained with most of the data. Presently at NATO.
Space processing applications rocket project SPAR 4, engineering report
NASA Technical Reports Server (NTRS)
Reeves, F. (Compiler)
1980-01-01
The materials processing experiments in space, conducted on the SPAR 4 Black Brant VC rocket, are described and discussed. The SPAR 4 payload configuration, the rocket performance, and the flight sequence are reported. The results, analyses, and anomalies of the four experiments are discussed. The experiments conducted were the uniform dispersions of crystallization processing, the contained polycrstalline solidification in low gravity, the containerless processing of ferromagnetic materials, and the containerless processing technology. The instrumentation operations, payload power relay anomaly, relay postflight operational test, and relay postflight shock test are reported.
O'Reilly, Daria; Tarride, Jean-Eric; Goeree, Ron; Lokker, Cynthia; McKibbon, K Ann
2012-01-01
To conduct a systematic review and synthesis of the evidence surrounding the cost-effectiveness of health information technology (HIT) in the medication process. Peer-reviewed electronic databases and gray literature were searched to identify studies on HIT used to assist in the medication management process. Articles including an economic component were reviewed for further screening. For this review, full cost-effectiveness analyses, cost-utility analyses and cost-benefit analyses, as well as cost analyses, were eligible for inclusion and synthesis. The 31 studies included were heterogeneous with respect to the HIT evaluated, setting, and economic methods used. Thus the data could not be synthesized, and a narrative review was conducted. Most studies evaluated computer decision support systems in hospital settings in the USA, and only five of the studied performed full economic evaluations. Most studies merely provided cost data; however, useful economic data involves far more input. A full economic evaluation includes a full enumeration of the costs, synthesized with the outcomes of the intervention. The quality of the economic literature in this area is poor. A few studies found that HIT may offer cost advantages despite their increased acquisition costs. However, given the uncertainty that surrounds the costs and outcomes data, and limited study designs, it is difficult to reach any definitive conclusion as to whether the additional costs and benefits represent value for money. Sophisticated concurrent prospective economic evaluations need to be conducted to address whether HIT interventions in the medication management process are cost-effective.
The Examination of Teacher Burnout in Turkey: A Meta-Analysis
ERIC Educational Resources Information Center
Yorulmaz, Yilmaz Ilker; Altinkurt, Yahya
2018-01-01
The purpose of this study is to determine the effect of gender, marital status, subject matter, school type, educational status and seniority variables on teacher burnout. In this regard, a meta-analysis was conducted for the studies on teacher burnout in Turkey. The effect size analyses were performed with 100 studies for gender, 73 for marital…
Microfluidic platform for multiplexed detection in single cells and methods thereof
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Meiye; Singh, Anup K.
The present invention relates to a microfluidic device and platform configured to conduct multiplexed analysis within the device. In particular, the device allows multiple targets to be detected on a single-cell level. Also provided are methods of performing multiplexed analyses to detect one or more target nucleic acids, proteins, and post-translational modifications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-04-01
This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Point Lonely radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.
MOFA Software for the COBRA Toolbox
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griesemer, Marc; Navid, Ali
MOFA-COBRA is a software code for Matlab that performs Multi-Objective Flux Analysis (MOFA), a solving of linear programming problems. Teh leading software package for conducting different types of analyses using constrain-based models is the COBRA Toolbox for Matlab. MOFA-COBRA is an added tool for COBRA that solves multi-objective problems using a novel algorithm.
Computer Access and Computer Use for Science Performance of Racial and Linguistic Minority Students
ERIC Educational Resources Information Center
Chang, Mido; Kim, Sunha
2009-01-01
This study examined the effects of computer access and computer use on the science achievement of elementary school students, with focused attention on the effects for racial and linguistic minority students. The study used the Early Childhood Longitudinal Study (ECLS-K) database and conducted statistical analyses with proper weights and…
ERIC Educational Resources Information Center
McLaughlin, Daniel; Smorodin, Calla; Smorodin, Ted; Timms, Mike
A study was conducted to determine how the Career Preparation Assessment portfolio (CPA), tailored to be used in local school reform efforts, was implemented in 10 schools in 1998-99. The research was organized and reported using these four clusters of research questions: tailoring the CPA, implementation, student performance and assessment, and…
ERIC Educational Resources Information Center
Dillon, Frank; Worthington, Roger L.
2003-01-01
Five studies on the development of the Lesbian, Gay, and Bisexual Affirmative Counseling Self-Efficacy Inventory (LGB-CSI) were conducted. Exploratory and confirmatory factor analyses of an initial pool of 64 items yielded 5 factors that assess counselor self-efficacy to perform lesbian, gay, and bisexual (LGB) affirmative counseling behaviors…
ERIC Educational Resources Information Center
DuPaul, George J.; Eckert, Tanya L.; Vilardo, Brigid
2012-01-01
A meta-analysis evaluating the effects of school-based interventions for students with attention deficit hyperactivity disorder was conducted by examining 60 outcome studies between 1996 and 2010 that yielded 85 effect sizes. Separate analyses were performed for studies employing between-subjects, within- subjects, and single-subject experimental…
ERIC Educational Resources Information Center
Woolf, Katherine; Haq, Inam; McManus, I. Chris; Higham, Jenny; Dacre, Jane
2008-01-01
Evidence shows that medical students from Minority Ethnic (ME) backgrounds and male medical students underperform in undergraduate examinations. Our study confirmed these findings in first year clinical (year 3) medical students, and further explored this disparity in performance. We conducted a series of meta-analyses to measure the effects of…
Using SPEEDES to simulate the blue gene interconnect network
NASA Technical Reports Server (NTRS)
Springer, P.; Upchurch, E.
2003-01-01
JPL and the Center for Advanced Computer Architecture (CACR) is conducting application and simulation analyses of BG/L in order to establish a range of effectiveness for the Blue Gene/L MPP architecture in performing important classes of computations and to determine the design sensitivity of the global interconnect network in support of real world ASCI application execution.
Productivity of public hospitals in Nepal: a data envelopment analysis
Ashton, Toni
2017-01-01
Objectives Public hospitals in Nepal account for a major share of the total health budget. Therefore, questions are often asked about the performance of these hospitals. Existing measures of performance are limited to historical ratio analyses without any benchmarks. The objective of this study is to explore the trends in inputs, outputs and productivity changes in Nepalese public hospitals from 2011–2012 to 2013–2014. Setting and participants The study was conducted among 32 Nepalese public hospitals (23 district level and 9 higher level) for the three fiscal years from 2011–2012 to 2013–2014. Outcome measures First, basic ratio analyses were conducted for the input and output measures over the study years. Then, Malmquist productivity change scores were obtained using data envelopment analysis. Aggregated as well as separate analyses were conducted for district level and higher level hospitals. Results Real expenditures of the sampled hospitals declined over the 3-year period from an average of US$ 371 000 in year 1 to US$ 368 730 in year 2 and US$ 328680 in year 3. The average aggregated hospital outputs increased marginally from 8276 in 2011–2012 to 8613 in 2013–2014. The total factor productivity of the study hospitals declined by 6.9% annually from 2011–2012 to 2013–2014. Of the total 32 hospitals, productivity increased in only 12 (37.5%) hospitals and declined in the remaining 20 hospitals. The total factor productivity loss was influenced by a decline in technology change, despite an increase in efficiency. Conclusions In general, productivity of the study hospitals declined over the study period. Availability and accessibility of accurate, detailed and consistent measures of hospital inputs and outputs is a major challenge for this type of analysis. PMID:28729314
A Study of Testing Different Mandrels for Electroforming Nickel
NASA Astrophysics Data System (ADS)
Murrell, Alex D. G.
Material failure is a prevalent problem in all engineering industries, particularly aerospace and automotive. The demand high-performance materials is higher than ever. Nickel is a metal that is favoured greatly because of its ability to withstand harsh operating conditions such as corrosive environments and extreme temperatures. Nickel parts can be produced by electroforming, a unique process that requires a removable conductive mandrel. An electroplating apparatus was set up at Tennessee Technological University to deposit nickel onto these mandrels where different methods of removal would be explored. Various different mandrels - conductive and non-conductive - were tested by nickel electroplating in a Watts nickel bath to establish a firm testing procedure. The nickel coatings were retrieved where possible and were analysed with appropriate methods. It was found that tin was the best material to use for a substrate through performance ranking, and a conductive polycarbonate was the worst material choice for a substrate. The substrates that demonstrated the easiest method of removal were tin and wax. Different methods of increasing - and also inhibiting - conductivity were applied to various substrates, where it was found that the use of a conductive graphite paint was particularly beneficial to the plating potential of a substrate.
Vibro-acoustic performance of newly designed tram track structures
NASA Astrophysics Data System (ADS)
Haladin, Ivo; Lakušić, Stjepan; Ahac, Maja
2017-09-01
Rail vehicles in interaction with a railway structure induce vibrations that are propagating to surrounding structures and cause noise disturbance in the surrounding areas. Since tram tracks in urban areas often share the running surface with road vehicles one of top priorities is to achieve low maintenance and long lasting structure. Research conducted in scope of this paper gives an overview of newly designed tram track structures designated for use on Zagreb tram network and their performance in terms of noise and vibration mitigation. Research has been conducted on a 150 m long test section consisted of three tram track types: standard tram track structure commonly used on tram lines in Zagreb, optimized tram structure for better noise and vibration mitigation and a slab track with double sleepers embedded in a concrete slab, which presents an entirely new approach of tram track construction in Zagreb. Track has been instrumented with acceleration sensors, strain gauges and revision shafts for inspection. Relative deformations give an insight into track structure dynamic load distribution through the exploitation period. Further the paper describes vibro-acoustic measurements conducted at the test site. To evaluate the track performance from the vibro-acoustical standpoint, detailed analysis of track decay rate has been analysed. Opposed to measurement technique using impact hammer for track decay rate measurements, newly developed measuring technique using vehicle pass by vibrations as a source of excitation has been proposed and analysed. Paper gives overview of the method, it’s benefits compared to standard method of track decay rate measurements and method evaluation based on noise measurements of the vehicle pass by.
Analyses of Response-Stimulus Sequences in Descriptive Observations
ERIC Educational Resources Information Center
Samaha, Andrew L.; Vollmer, Timothy R.; Borrero, Carrie; Sloman, Kimberly; Pipkin, Claire St. Peter; Bourret, Jason
2009-01-01
Descriptive observations were conducted to record problem behavior displayed by participants and to record antecedents and consequences delivered by caregivers. Next, functional analyses were conducted to identify reinforcers for problem behavior. Then, using data from the descriptive observations, lag-sequential analyses were conducted to examine…
Performance testing and analyses of the VSC-17 ventilated concrete cask. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
McKinnon, M.A.; Dodge, R.E.; Schmitt, R.C.
1992-05-01
This document details performance test which was conducted on a Pacific Sierra Nuclear VSC-17 ventilated concrete storage cask configured for pressurized-water reactor (PWR) spent fuel. The performance test consisted of loading the VSC-17 cask with 17 canisters of consolidated PWR spent fuel from Virginia Power`s Surry and Florida Power & Light Turkey Point reactors. Cask surface, concrete, air channel surfaces, and fuel canister guide tube temperatures were measured, as were cask surface gamma and neutron dose rates. Testing was performed with vacuum, nitrogen, and helium backfill environments in a vertical cask orientation. Data on spent fuel integrity were also obtained.
Stepp, J.C.; Wong, I.; Whitney, J.; Quittmeyer, R.; Abrahamson, N.; Toro, G.; Young, S.R.; Coppersmith, K.; Savy, J.; Sullivan, T.
2001-01-01
Probabilistic seismic hazard analyses were conducted to estimate both ground motion and fault displacement hazards at the potential geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. The study is believed to be the largest and most comprehensive analyses ever conducted for ground-shaking hazard and is a first-of-a-kind assessment of probabilistic fault displacement hazard. The major emphasis of the study was on the quantification of epistemic uncertainty. Six teams of three experts performed seismic source and fault displacement evaluations, and seven individual experts provided ground motion evaluations. State-of-the-practice expert elicitation processes involving structured workshops, consensus identification of parameters and issues to be evaluated, common sharing of data and information, and open exchanges about the basis for preliminary interpretations were implemented. Ground-shaking hazard was computed for a hypothetical rock outcrop at -300 m, the depth of the potential waste emplacement drifts, at the designated design annual exceedance probabilities of 10-3 and 10-4. The fault displacement hazard was calculated at the design annual exceedance probabilities of 10-4 and 10-5.
Neyeloff, Jeruza L; Fuchs, Sandra C; Moreira, Leila B
2012-01-20
Meta-analyses are necessary to synthesize data obtained from primary research, and in many situations reviews of observational studies are the only available alternative. General purpose statistical packages can meta-analyze data, but usually require external macros or coding. Commercial specialist software is available, but may be expensive and focused in a particular type of primary data. Most available softwares have limitations in dealing with descriptive data, and the graphical display of summary statistics such as incidence and prevalence is unsatisfactory. Analyses can be conducted using Microsoft Excel, but there was no previous guide available. We constructed a step-by-step guide to perform a meta-analysis in a Microsoft Excel spreadsheet, using either fixed-effect or random-effects models. We have also developed a second spreadsheet capable of producing customized forest plots. It is possible to conduct a meta-analysis using only Microsoft Excel. More important, to our knowledge this is the first description of a method for producing a statistically adequate but graphically appealing forest plot summarizing descriptive data, using widely available software.
2012-01-01
Background Meta-analyses are necessary to synthesize data obtained from primary research, and in many situations reviews of observational studies are the only available alternative. General purpose statistical packages can meta-analyze data, but usually require external macros or coding. Commercial specialist software is available, but may be expensive and focused in a particular type of primary data. Most available softwares have limitations in dealing with descriptive data, and the graphical display of summary statistics such as incidence and prevalence is unsatisfactory. Analyses can be conducted using Microsoft Excel, but there was no previous guide available. Findings We constructed a step-by-step guide to perform a meta-analysis in a Microsoft Excel spreadsheet, using either fixed-effect or random-effects models. We have also developed a second spreadsheet capable of producing customized forest plots. Conclusions It is possible to conduct a meta-analysis using only Microsoft Excel. More important, to our knowledge this is the first description of a method for producing a statistically adequate but graphically appealing forest plot summarizing descriptive data, using widely available software. PMID:22264277
How individual participant data meta-analyses have influenced trial design, conduct, and analysis.
Tierney, Jayne F; Pignon, Jean-Pierre; Gueffyier, Francois; Clarke, Mike; Askie, Lisa; Vale, Claire L; Burdett, Sarah
2015-11-01
To demonstrate how individual participant data (IPD) meta-analyses have impacted directly on the design and conduct of trials and highlight other advantages IPD might offer. Potential examples of the impact of IPD meta-analyses on trials were identified at an international workshop, attended by individuals with experience in the conduct of IPD meta-analyses and knowledge of trials in their respective clinical areas. Experts in the field who did not attend were asked to provide any further examples. We then examined relevant trial protocols, publications, and Web sites to verify the impacts of the IPD meta-analyses. A subgroup of workshop attendees sought further examples and identified other aspects of trial design and conduct that may inform IPD meta-analyses. We identified 52 examples of IPD meta-analyses thought to have had a direct impact on the design or conduct of trials. After screening relevant trial protocols and publications, we identified 28 instances where IPD meta-analyses had clearly impacted on trials. They have influenced the selection of comparators and participants, sample size calculations, analysis and interpretation of subsequent trials, and the conduct and analysis of ongoing trials, sometimes in ways that would not possible with systematic reviews of aggregate data. We identified additional potential ways that IPD meta-analyses could be used to influence trials. IPD meta-analysis could be better used to inform the design, conduct, analysis, and interpretation of trials. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
How individual participant data meta-analyses have influenced trial design, conduct, and analysis
Tierney, Jayne F.; Pignon, Jean-Pierre; Gueffyier, Francois; Clarke, Mike; Askie, Lisa; Vale, Claire L.; Burdett, Sarah; Alderson, P.; Askie, L.; Bennett, D.; Burdett, S.; Clarke, M.; Dias, S.; Emberson, J.; Gueyffier, F.; Iorio, A.; Macleod, M.; Mol, B.W.; Moons, C.; Parmar, M.; Perera, R.; Phillips, R.; Pignon, J.P.; Rees, J.; Reitsma, H.; Riley, R.; Rovers, M.; Rydzewska, L.; Schmid, C.; Shepperd, S.; Stenning, S.; Stewart, L.; Tierney, J.; Tudur Smith, C.; Vale, C.; Welge, J.; White, I.; Whiteley, W.
2015-01-01
Objectives To demonstrate how individual participant data (IPD) meta-analyses have impacted directly on the design and conduct of trials and highlight other advantages IPD might offer. Study Design and Setting Potential examples of the impact of IPD meta-analyses on trials were identified at an international workshop, attended by individuals with experience in the conduct of IPD meta-analyses and knowledge of trials in their respective clinical areas. Experts in the field who did not attend were asked to provide any further examples. We then examined relevant trial protocols, publications, and Web sites to verify the impacts of the IPD meta-analyses. A subgroup of workshop attendees sought further examples and identified other aspects of trial design and conduct that may inform IPD meta-analyses. Results We identified 52 examples of IPD meta-analyses thought to have had a direct impact on the design or conduct of trials. After screening relevant trial protocols and publications, we identified 28 instances where IPD meta-analyses had clearly impacted on trials. They have influenced the selection of comparators and participants, sample size calculations, analysis and interpretation of subsequent trials, and the conduct and analysis of ongoing trials, sometimes in ways that would not possible with systematic reviews of aggregate data. We identified additional potential ways that IPD meta-analyses could be used to influence trials. Conclusions IPD meta-analysis could be better used to inform the design, conduct, analysis, and interpretation of trials. PMID:26186982
Faggion, Clovis Mariano; Wu, Yun-Chun; Scheidgen, Moritz; Tu, Yu-Kang
2015-01-01
Risk of bias (ROB) may threaten the internal validity of a clinical trial by distorting the magnitude of treatment effect estimates, although some conflicting information on this assumption exists. The objective of this study was evaluate the effect of ROB on the magnitude of treatment effect estimates in randomized controlled trials (RCTs) in periodontology and implant dentistry. A search for Cochrane systematic reviews (SRs), including meta-analyses of RCTs published in periodontology and implant dentistry fields, was performed in the Cochrane Library in September 2014. Random-effect meta-analyses were performed by grouping RCTs with different levels of ROBs in three domains (sequence generation, allocation concealment, and blinding of outcome assessment). To increase power and precision, only SRs with meta-analyses including at least 10 RCTs were included. Meta-regression was performed to investigate the association between ROB characteristics and the magnitudes of intervention effects in the meta-analyses. Of the 24 initially screened SRs, 21 SRs were excluded because they did not include at least 10 RCTs in the meta-analyses. Three SRs (two from periodontology field) generated information for conducting 27 meta-analyses. Meta-regression did not reveal significant differences in the relationship of the ROB level with the size of treatment effect estimates, although a trend for inflated estimates was observed in domains with unclear ROBs. In this sample of RCTs, high and (mainly) unclear risks of selection and detection biases did not seem to influence the size of treatment effect estimates, although several confounders might have influenced the strength of the association.
NASA Technical Reports Server (NTRS)
Latham, T. S.; Rodgers, R. J.
1972-01-01
Analytical studies were continued to identify the design and performance characteristics of a small-scale model of a nuclear light bulb unit cell suitable for testing in a nuclear furnace reactor. Emphasis was placed on calculating performance characteristics based on detailed radiant heat transfer analyses, on designing the test assembly for ease of insertion, connection, and withdrawal at the reactor test cell, and on determining instrumentation and test effluent handling requirements. In addition, a review of candidate test reactors for future nuclear light bulb in-reactor tests was conducted.
Advanced space program studies: Overall executive summary
NASA Technical Reports Server (NTRS)
Sitney, L. R.
1974-01-01
Studies were conducted to provide NASA with advanced planning analyses which relate integrated space program goals and options to credible technical capabilities, applications potential, and funding resources. The studies concentrated on the following subjects: (1) upper stage options for the space transportation system based on payload considerations, (2) space servicing and standardization of payloads, (3) payload operations, and (4) space transportation system economic analyses related to user charges and new space applications. A systems cost/performance model was developed to synthesize automated, unmanned spacecraft configurations based on the system requirements and a list of equipments at the assembly level.
Continuous performance task in ADHD: Is reaction time variability a key measure?
Levy, Florence; Pipingas, Andrew; Harris, Elizabeth V; Farrow, Maree; Silberstein, Richard B
2018-01-01
To compare the use of the Continuous Performance Task (CPT) reaction time variability (intraindividual variability or standard deviation of reaction time), as a measure of vigilance in attention-deficit hyperactivity disorder (ADHD), and stimulant medication response, utilizing a simple CPT X-task vs an A-X-task. Comparative analyses of two separate X-task vs A-X-task data sets, and subgroup analyses of performance on and off medication were conducted. The CPT X-task reaction time variability had a direct relationship to ADHD clinician severity ratings, unlike the CPT A-X-task. Variability in X-task performance was reduced by medication compared with the children's unmedicated performance, but this effect did not reach significance. When the coefficient of variation was applied, severity measures and medication response were significant for the X-task, but not for the A-X-task. The CPT-X-task is a useful clinical screening test for ADHD and medication response. In particular, reaction time variability is related to default mode interference. The A-X-task is less useful in this regard.
Baxter, Ruth; Taylor, Natalie; Kellar, Ian; Pye, Victoria; Mohammed, Mohammed A; Lawton, Rebecca
2018-02-16
The positive deviance approach seeks to identify and learn from exceptional performers. Although a framework exists to apply positive deviance within healthcare organisations, there is limited guidance to support its implementation. The approach has also rarely explored exceptional performance on broad outcomes, been implemented at ward level, or applied within the UK. This study develops and critically appraises a pragmatic method for identifying positively deviant wards using a routinely collected, broad measure of patient safety. A two-phased observational study was conducted. During phase 1, cross-sectional and temporal analyses of Safety Thermometer data were conducted to identify a discrete group of positively deviant wards that consistently demonstrated exceptional levels of safety. A group of matched comparison wards with above average performances were also identified. During phase 2, multidisciplinary staff and patients on the positively deviant and comparison wards completed surveys to explore whether their perceptions of safety supported the identification of positively deviant wards. 34 elderly medical wards within a northern region of England, UK. Multidisciplinary staff (n=161) and patients (n=188) clustered within nine positively deviant and comparison wards. Phase 1: A combination of analyses identified five positively deviant wards that performed best in the region, outperformed their organisation and performed consistently well over 12 months. Five above average matched comparator wards were also identified. Phase 2: Staff and patient perceptions of safety generally supported the identification of positively deviant wards using Safety Thermometer data, although patient perceptions of safety were less concordant with the routinely collected data. This study tentatively supports a pragmatic method of using routinely collected data to identify positively deviant elderly medical wards; however, it also highlights the various challenges that are faced when conducting the first stage of the positive deviance approach. UK Clinical Research Network Portfolio (reference-18050). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Taylor, Natalie; Kellar, Ian; Pye, Victoria; Mohammed, Mohammed A; Lawton, Rebecca
2018-01-01
Objective The positive deviance approach seeks to identify and learn from exceptional performers. Although a framework exists to apply positive deviance within healthcare organisations, there is limited guidance to support its implementation. The approach has also rarely explored exceptional performance on broad outcomes, been implemented at ward level, or applied within the UK. This study develops and critically appraises a pragmatic method for identifying positively deviant wards using a routinely collected, broad measure of patient safety. Design A two-phased observational study was conducted. During phase 1, cross-sectional and temporal analyses of Safety Thermometer data were conducted to identify a discrete group of positively deviant wards that consistently demonstrated exceptional levels of safety. A group of matched comparison wards with above average performances were also identified. During phase 2, multidisciplinary staff and patients on the positively deviant and comparison wards completed surveys to explore whether their perceptions of safety supported the identification of positively deviant wards. Setting 34 elderly medical wards within a northern region of England, UK. Participants Multidisciplinary staff (n=161) and patients (n=188) clustered within nine positively deviant and comparison wards. Results Phase 1: A combination of analyses identified five positively deviant wards that performed best in the region, outperformed their organisation and performed consistently well over 12 months. Five above average matched comparator wards were also identified. Phase 2: Staff and patient perceptions of safety generally supported the identification of positively deviant wards using Safety Thermometer data, although patient perceptions of safety were less concordant with the routinely collected data. Conclusions This study tentatively supports a pragmatic method of using routinely collected data to identify positively deviant elderly medical wards; however, it also highlights the various challenges that are faced when conducting the first stage of the positive deviance approach. Trial registration number UK Clinical Research Network Portfolio (reference-18050). PMID:29453303
NASA Technical Reports Server (NTRS)
Theologus, G. C.; Wheaton, G. R.; Mirabella, A.; Brahlek, R. E.
1973-01-01
A set of 36 relatively independent categories of human performance were identified. These categories encompass human performance in the cognitive, perceptual, and psychomotor areas, and include diagnostic measures and sensitive performance metrics. Then a prototype standardized test battery was constructed, and research was conducted to obtain information on the sensitivity of the tests to stress, the sensitivity of selected categories of performance degradation, the time course of stress effects on each of the selected tests, and the learning curves associated with each test. A research project utilizing a three factor partially repeated analysis of covariance design was conducted in which 60 male subjects were exposed to variations in noise level and quality during performance testing. Effects of randomly intermittent noise on performance of the reaction time tests were observed, but most of the other performance tests showed consistent stability. The results of 14 analyses of covariance of the data taken from the performance of the 60 subjects on the prototype standardized test battery provided information which will enable the final development and test of a standardized test battery and the associated development of differential sensitivity metrics and diagnostic classificatory system.
NASA Technical Reports Server (NTRS)
Zachary, A. T.
1973-01-01
Analysis and design of an optimum LO2/LH2, combustion topping cycle, 88,964 Newtons (20,000-pound) thrust, liquid rocket engine was conducted. The design selected is well suited to high-energy, upper-stage engine applications such as the Space Tug and embodies features directed toward optimization of vehicle performance. A configuration selection was conducted based on prior Air Force Contracts, and additional criteria for optimum stage performance. Following configuration selection, analyses and design of the major components and engine systems were conducted to sufficient depth to provide layout drawings suitable for subsequent detailing. In addition, engine packaging to a common interface and a retractable nozzle concept were defined. Alternative development plans and related costs were also established. The design embodies high-performance, low-weight, low NPSH requirements (saturated propellant inlet conditions at start), idle-mode operation, and autogenous pressurization. The design is the result of the significant past and current LO2/LH2 technology efforts of the NASA centers and the Air Force, as well as company-funded programs.
Edwards, Jerri D; Ruva, Christine L; O'Brien, Jennifer L; Haley, Christine B; Lister, Jennifer J
2013-06-01
The purpose of these analyses was to examine mediators of the transfer of cognitive speed of processing training to improved everyday functional performance (J. D. Edwards, V. G. Wadley,, D. E. Vance, D. L. Roenker, & K. K. Ball, 2005, The impact of speed of processing training on cognitive and everyday performance. Aging & Mental Health, 9, 262-271). Cognitive speed of processing and visual attention (as measured by the Useful Field of View Test; UFOV) were examined as mediators of training transfer. Secondary data analyses were conducted from the Staying Keen in Later Life (SKILL) study, a randomized cohort study including 126 community dwelling adults 63 to 87 years of age. In the SKILL study, participants were randomized to an active control group or cognitive speed of processing training (SOPT), a nonverbal, computerized intervention involving perceptual practice of visual tasks. Prior analyses found significant effects of training as measured by the UFOV and Timed Instrumental Activities of Daily Living (TIADL) Tests. Results from the present analyses indicate that speed of processing for a divided attention task significantly mediated the effect of SOPT on everyday performance (e.g., TIADL) in a multiple mediation model accounting for 91% of the variance. These findings suggest that everyday functional improvements found from SOPT are directly attributable to improved UFOV performance, speed of processing for divided attention in particular. Targeting divided attention in cognitive interventions may be important to positively affect everyday functioning among older adults. PsycINFO Database Record (c) 2013 APA, all rights reserved.
An evaluation of GTAW-P versus GTA welding of alloy 718
NASA Technical Reports Server (NTRS)
Gamwell, W. R.; Kurgan, C.; Malone, T. W.
1991-01-01
Mechanical properties were evaluated to determine statistically whether the pulsed current gas tungsten arc welding (GTAW-P) process produces welds in alloy 718 with room temperature structural performance equivalent to current Space Shuttle Main Engine (SSME) welds manufactured by the constant current GTAW-P process. Evaluations were conducted on two base metal lots, two filler metal lots, two heat input levels, and two welding processes. The material form was 0.125-inch (3.175-mm) alloy 718 sheet. Prior to welding, sheets were treated to either the ST or STA-1 condition. After welding, panels were left as welded or heat treated to the STA-1 condition, and weld beads were left intact or machined flush. Statistical analyses were performed on yield strength, ultimate tensile strength (UTS), and high cycle fatigue (HCF) properties for all the post welded material conditions. Analyses of variance were performed on the data to determine if there were any significant effects on UTS or HCF life due to variations in base metal, filler metal, heat input level, or welding process. Statistical analyses showed that the GTAW-P process does produce welds with room temperature structural performance equivalent to current SSME welds manufactured by the GTAW process, regardless of prior material condition or post welding condition.
Zander, Britta; Busse, Reinhard
2017-02-22
Adequate performance assessment benefits from the use of disaggregated data to allow a proper evaluation of health systems. Since routinely collected data are usually not disaggregated enough to allow stratified analyses of healthcare needs, utilisation, cost and quality across different sectors, international research projects could fill this gap by exploring means to data collection or even providing individual-level data. The aim of this paper is therefore to (1) study the availability and accessibility of relevant European-funded health projects, and (2) to analyse their contents and methodologies. The European Commission Public Health Projects Database and CORDIS were searched for eligible projects, which were then analysed by information openly available online. Overall, only a few of the 39 identified projects produced data useful for proper performance assessment, due to, for example, lacking available or accessible data, or poor linkage of health status to costs and patient experiences. Other problems were insufficient databases to identify projects and poor communication of project contents and results. A new approach is necessary to improve accessibility to and coverage of data on outcomes, quality and costs of health systems enabling decision-makers and health professionals to properly assess performance.
Wojtalik, Jessica A; Eack, Shaun M; Keshavan, Matcheri S
2013-01-10
The Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) is a key measure of social cognition in schizophrenia that has good psychometric properties and is recommended by the MATRICS committee. As a way to further investigate the validity of the MSCEIT, this study sought to examine the neurobiological correlates of MSCEIT performance in patients with early course schizophrenia. A total of 51 patients diagnosed with early course, stabilized schizophrenia or schizoaffective disorder completed structural magnetic resonance imaging (MRI) scans and the MSCEIT. Investigation of the associations between MSCEIT performance and gray matter morphology was examined by conducting voxel-based morphometry (VBM) analyses across hypothesized social-cognitive regions of interest using automated anatomical labeling in Statistical Parametric Mapping Software, version 5 (SPM5). All VBM analyses utilized general linear models examining gray matter density partitioned images, adjusting for demographic and illness-related confounds. VBM results were then followed up with confirmatory volumetric analyses. Patients with poorer overall and Facilitating, Understanding, and Managing Emotions subscale performances on the MSCEIT showed significantly reduced gray matter density in the left parahippocampal gyrus. Additionally, attenuated performance on the Facilitating and Managing Emotions subscales was significantly associated with reduced right posterior cingulate gray matter density. All associations observed between MSCEIT performance and gray matter density were supported with confirmatory gray matter volumetric analyses, with the exception of the association between the right posterior cingulate and the facilitation of emotions. These findings provide additional evidence for the MSCEIT as a valid social-cognitive measure by elucidating its correlates with neurobiological structures commonly implicated in emotion processing. These findings provide additional biological evidence supporting the use of the MSCEIT in cognitive enhancing clinical trials in schizophrenia. Copyright © 2012 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
French, Sean B.; Shuman, Robert
2012-04-17
The Los Alamos National Laboratory (LANL or the Laboratory) generates radioactive waste as a result of various activities. Operational or institutional waste is generated from a wide variety of research and development activities including nuclear weapons development, energy production, and medical research. Environmental restoration (ER), and decontamination and decommissioning (D and D) waste is generated as contaminated sites and facilities at LANL undergo cleanup or remediation. The majority of this waste is low-level radioactive waste (LLW) and is disposed of at the Technical Area 54 (TA-54), Area G disposal facility. U.S. Department of Energy (DOE) Order 435.1 (DOE, 2001) requiresmore » that radioactive waste be managed in a manner that protects public health and safety, and the environment. To comply with this order, DOE field sites must prepare and maintain site-specific radiological performance assessments for LLW disposal facilities that accept waste after September 26, 1988. Furthermore, sites are required to conduct composite analyses that account for the cumulative impacts of all waste that has been (or will be) disposed of at the facilities and other sources of radioactive material that may interact with the facilities. Revision 4 of the Area G performance assessment and composite analysis was issued in 2008 (LANL, 2008). These analyses estimate rates of radionuclide release from the waste disposed of at the facility, simulate the movement of radionuclides through the environment, and project potential radiation doses to humans for several on-site and off-site exposure scenarios. The assessments are based on existing site and disposal facility data and on assumptions about future rates and methods of waste disposal. The accuracy of the performance assessment and composite analysis depends upon the validity of the data used and assumptions made in conducting the analyses. If changes in these data and assumptions are significant, they may invalidate or call into question certain aspects of the analyses. For example, if the volumes and activities of waste disposed of during the remainder of the disposal facility's lifetime differ significantly from those projected, the doses projected by the analyses may no longer apply. DOE field sites are required to implement a performance assessment and composite analysis maintenance program. The purpose of this program is to ensure the continued applicability of the analyses through incremental improvement of the level of understanding of the disposal site and facility. Site personnel are required to conduct field and experimental work to reduce the uncertainty in the data and models used in the assessments. Furthermore, they are required to conduct periodic reviews of waste receipts, comparing them to projected waste disposal rates. The radiological inventory for Area G was updated in conjunction with Revision 4 of the performance assessment and composite analysis (Shuman, 2008). That effort used disposal records and other sources of information to estimate the quantities of radioactive waste that have been disposed of at Area G from 1959, the year the facility started receiving waste on a routine basis, through 2007. It also estimated the quantities of LLW that will require disposal from 2008 through 2044, the year in which it is assumed that disposal operations at Area G will cease. This report documents the fourth review of Area G disposal receipts since the inventory was updated and examines information for waste placed in the ground during fiscal years (FY) 2008 through 2011. The primary objective of the disposal receipt review is to ensure that the future waste inventory projections developed for the performance assessment and composite analysis are consistent with the actual types and quantities of waste being disposed of at Area G. Toward this end, the disposal data that are the subject of this review are used to update the future waste inventory projections for the disposal facility. These projections are compared to the future inventory projections that were developed for Revision 4 of the performance assessment and composite analysis. The approach used to characterize the FY 2008 through 2011 waste is generally the same as that used to characterize the inventory for the Revision 4 analyses (Shuman, 2008). This methodology is described in Section 2. The results of the disposal receipt review are presented in Section 3 and discussed in terms of their significance to the Area G analyses.« less
Estimated prevalence of halitosis: a systematic review and meta-regression analysis.
Silva, Manuela F; Leite, Fábio R M; Ferreira, Larissa B; Pola, Natália M; Scannapieco, Frank A; Demarco, Flávio F; Nascimento, Gustavo G
2018-01-01
This study aims to conduct a systematic review to determine the prevalence of halitosis in adolescents and adults. Electronic searches were performed using four different databases without restrictions: PubMed, Scopus, Web of Science, and SciELO. Population-based observational studies that provided data about the prevalence of halitosis in adolescents and adults were included. Additionally, meta-analyses, meta-regression, and sensitivity analyses were conducted to synthesize the evidence. A total of 584 articles were initially found and considered for title and abstract evaluation. Thirteen articles met inclusion criteria. The combined prevalence of halitosis was found to be 31.8% (95% CI 24.6-39.0%). Methodological aspects such as the year of publication and the socioeconomic status of the country where the study was conducted seemed to influence the prevalence of halitosis. Our results demonstrated that the estimated prevalence of halitosis was 31.8%, with high heterogeneity between studies. The results suggest a worldwide trend towards a rise in halitosis prevalence. Given the high prevalence of halitosis and its complex etiology, dental professionals should be aware of their roles in halitosis prevention and treatment.
Heat Transfer Issues in Finite Element Analysis of Bounding Accidents in PPCS Models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pampin, R.; Karditsas, P.J.
2005-05-15
Modelling of temperature excursions in structures of conceptual power plants during hypothetical worst-case accidents has been performed within the European Power Plant Conceptual Study (PPCS). A new, 3D finite elements (FE) based tool, coupling the different calculations to the same tokamak geometry, has been extensively used to conduct the neutron transport, activation and thermal analyses for all PPCS plant models. During a total loss of cooling, the usual assumption for the bounding accident, passive removal of the decay heat from activated materials depends on conduction and radiation heat exchange between components. This paper presents and discusses results obtained during themore » PPCS bounding accident thermal analyses, examining the following issues: (a) radiation heat exchange between the inner surfaces of the tokamak, (b) the presence of air within the cryostat volume, and the heat flow arising from the circulation pattern provided by temperature differences between various parts, and (c) the thermal conductivity of pebble beds, and its degradation due to exposure to neutron irradiation, affecting the heat transfer capability and thermal response of a blanket based on these components.« less
Factors Affecting Success in the Professional Entry Exam for Accountants in Brazil
ERIC Educational Resources Information Center
Lima Rodrigues, Lúcia; Pinho, Carlos; Bugarim, Maria Clara; Craig, Russell; Machado, Diego
2018-01-01
This paper explores factors that have affected the success of candidates in the professional entry exam conducted by Brazil's Federal Council of Accounting. We analyse results of 18,948 candidates who sat for the exam in 2012, using a logistic regression model and the key indicators used by government to monitor the performance of higher education…
ERIC Educational Resources Information Center
Pereira, Maria A.
2011-01-01
This study examined the strength and the direction of the relationships between student (i.e., socioeconomic status, attendance, and gender) and school variables (i.e., formative assessment usage and ASI classification) found in the extant literature to influence student achievement in language arts and mathematics. Analyses were conducted using…
Using Peer Assessment to Evaluate Teamwork from a Multidisciplinary Perspective
ERIC Educational Resources Information Center
Planas-Lladó, Anna; Feliu, Lidia; Castro, Francesc; Fraguell, Rosa Maria; Arbat, Gerard; Pujol, Joan; Suñol, Joan Josep; Daunis-i-Estadella, Pepus
2018-01-01
This article analyses the use of peer evaluation as a tool for evaluating teamwork and students' perceptions of this type of evaluation. A study was conducted of six subjects included on five degree courses at the University of Girona. In all of these subjects, students carried out a team activity, evaluated the performance of the team and the…
Sulfur Oxides Risk and Exposure Assessment Planning ...
In conducting risk/exposure assessments for the Sulfur Oxides NAAQS review, EPA will first develop a draft Scope and Methods Plan which will describe the proposed scope of the quantitative and qualitative analyses to be performed and the tools/methods that may be employed Provide opportunity for CASAC feedback on EPA's plans for the risk and exposure assessment for the Sulfur Oxides NAAQS review
ERIC Educational Resources Information Center
Dogan, Mustafa
2010-01-01
This study explores Turkish primary mathematics trainee teachers' attitudes to computer and technology. A survey was conducted with a self constructed questionnaire. Piloting, factor and reliability ([alpha] = 0.94) analyses were performed. The final version of the questionnaire has three parts with a total of 48 questions including a Likert type…
ERIC Educational Resources Information Center
Colom, Roberto; Shih, Pei Chun
2004-01-01
A study was conducted in which 226 participants performed 12 tests, 6 thought to reflect verbal, quantitative, and spatial working memory (WM), and 6 of crystallized (Gc), fluid (Gf), and spatial (Gv) cognitive abilities. Confirmatory factor analyses (CFAs) were computed to test the unitary nature of the WM system. Six primary latent factors were…
Tse, Chi-Shing; Yap, Melvin J; Chan, Yuen-Lai; Sze, Wei Ping; Shaoul, Cyrus; Lin, Dan
2017-08-01
Using a megastudy approach, we developed a database of lexical variables and lexical decision reaction times and accuracy rates for more than 25,000 traditional Chinese two-character compound words. Each word was responded to by about 33 native Cantonese speakers in Hong Kong. This resource provides a valuable adjunct to influential mega-databases, such as the Chinese single-character, English, French, and Dutch Lexicon Projects. Three analyses were conducted to illustrate the potential uses of the database. First, we compared the proportion of variance in lexical decision performance accounted for by six word frequency measures and established that the best predictor was Cai and Brysbaert's (PLoS One, 5, e10729, 2010) contextual diversity subtitle frequency. Second, we ran virtual replications of three previously published lexical decision experiments and found convergence between the original experiments and the present megastudy. Finally, we conducted item-level regression analyses to examine the effects of theoretically important lexical variables in our normative data. This is the first publicly available large-scale repository of behavioral responses pertaining to Chinese two-character compound word processing, which should be of substantial interest to psychologists, linguists, and other researchers.
Boschetti, Mirco; Nutini, Francesco; Manfron, Giacinto; Brivio, Pietro Alessandro; Nelson, Andrew
2014-01-01
Identifying managed flooding in paddy fields is commonly used in remote sensing to detect rice. Such flooding, followed by rapid vegetation growth, is a reliable indicator to discriminate rice. Spectral indices (SIs) are often used to perform this task. However, little work has been done on determining which spectral combination in the form of Normalised Difference Spectral Indices (NDSIs) is most appropriate for surface water detection or which thresholds are most robust to separate water from other surfaces in operational contexts. To address this, we conducted analyses on satellite and field spectral data from an agronomic experiment as well as on real farming situations with different soil and plant conditions. Firstly, we review and select NDSIs proposed in the literature, including a new combination of visible and shortwave infrared bands. Secondly, we analyse spectroradiometric field data and satellite data to evaluate mixed pixel effects. Thirdly, we analyse MODIS data and Landsat data at four sites in Europe and Asia to assess NDSI performance in real-world conditions. Finally, we test the performance of the NDSIs on MODIS temporal profiles in the four sites. We also compared the NDSIs against a combined index previously used for agronomic flood detection. Analyses suggest that NDSIs using MODIS bands 4 and 7, 1 and 7, 4 and 6 or 1 and 6 perform best. A common threshold for each NDSI across all sites was more appropriate than locally adaptive thresholds. In general, NDSIs that use band 7 have a negligible increase in Commission Error over those that use band 6 but are more sensitive to water presence in mixed land cover conditions typical of moderate spatial resolution analyses. The best performing NDSI is comparable to the combined index but with less variability in performance across sites, suggesting a more succinct and robust flood detection method. PMID:24586381
Li, Li; Nguyen, Kim-Huong; Comans, Tracy; Scuffham, Paul
2018-04-01
Several utility-based instruments have been applied in cost-utility analysis to assess health state values for people with dementia. Nevertheless, concerns and uncertainty regarding their performance for people with dementia have been raised. To assess the performance of available utility-based instruments for people with dementia by comparing their psychometric properties and to explore factors that cause variations in the reported health state values generated from those instruments by conducting meta-regression analyses. A literature search was conducted and psychometric properties were synthesized to demonstrate the overall performance of each instrument. When available, health state values and variables such as the type of instrument and cognitive impairment levels were extracted from each article. A meta-regression analysis was undertaken and available covariates were included in the models. A total of 64 studies providing preference-based values were identified and included. The EuroQol five-dimension questionnaire demonstrated the best combination of feasibility, reliability, and validity. Meta-regression analyses suggested that significant differences exist between instruments, type of respondents, and mode of administration and the variations in estimated utility values had influences on incremental quality-adjusted life-year calculation. This review finds that the EuroQol five-dimension questionnaire is the most valid utility-based instrument for people with dementia, but should be replaced by others under certain circumstances. Although no utility estimates were reported in the article, the meta-regression analyses that examined variations in utility estimates produced by different instruments impact on cost-utility analysis, potentially altering the decision-making process in some circumstances. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Loads and Performance Data from a Wind-Tunnel Test of Generic Model Helicopter Rotor Blades
NASA Technical Reports Server (NTRS)
Yeager, William T., Jr.; Wilbur, Matthew L.
2005-01-01
An investigation was conducted in the NASA Langley Transonic Dynamics Tunnel to acquire data for use in assessing the ability of current and future comprehensive analyses to predict helicopter rotating-system and fixed-system vibratory loads. The investigation was conducted with a generic model helicopter rotor system using blades with rectangular planform, no built-in twist, uniform radial distribution of mass and stiffnesses, and a NACA 0012 airfoil section. Rotor performance data, as well as mean and vibratory components of blade bending and torsion moments, fixed-system forces and moments, and pitch link loads were obtained at advance ratios up to 0.35 for various combinations of rotor shaft angle-of-attack and collective pitch. The data are presented without analysis.
Spatial Analysis of Rice Blast in China at Three Different Scales.
Guo, Fangfang; Chen, Xinglong; Lu, Minghong; Yang, Li; Wang, Shi Wei; Wu, Bo Ming
2018-05-22
In this study, spatial analyses were conducted at three different scales to better understand the epidemiology of rice blast, a major rice disease caused by Magnaporthe oryzae. At regional scale, across the major rice production regions in China, rice blast incidence was monitored on 101 dates at 193 stations from June 10 th to Sep. 10 th during 2009-2014, and surveyed in 143 fields in September, 2016; at county scale, 3 surveys were done covering 1-5 counties in 2015-2016; and at field scale, blast was evaluated in 6 fields in 2015-2016. Spatial cluster and hot spot analyses were conducted in GIS on the geographical pattern of the disease at regional scale, and geostatistical analysis performed at all the three scales. Cluster and hot spot analyses revealed that high-disease areas were clustered in mountainous areas in China. Geostatistical analyses detected spatial dependence of blast incidence with influence ranges of 399 to 1080 km at regional scale, and 5 to 10 m at field scale, but not at county scale. The spatial patterns at different scales might be determined by inherent properties of rice blast and environmental driving forces, and findings from this study provide helpful information to sampling and management of rice blast.
Training Residential Staff to Conduct Trial-Based Functional Analyses
ERIC Educational Resources Information Center
Lambert, Joseph M.; Bloom, Sarah E.; Kunnavatana, S. Shanun; Collins, Shawnee D.; Clay, Casey J.
2013-01-01
We taught 6 supervisors of a residential service provider for adults with developmental disabilities to train 9 house managers to conduct trial-based functional analyses. Effects of the training were evaluated with a nonconcurrent multiple baseline. Results suggest that house managers can be trained to conduct trial-based functional analyses with…
Officer Career Development: Longitudinal Sample--Fiscal Year 1982
1991-10-01
Those that wish to access the database to conduct additional analyses, link it to or combine it with other databases, enlarge the database for the...link it to or combine it with other databases, enlarge the database for the conduct of trend analyses, etc., will find this data dictionary an...analyses, link it to or combine it with other databases, enlarge the database for the conduct of trend analyses, etc., will find this data dictionary
Development of the PROMIS nicotine dependence item banks.
Shadel, William G; Edelen, Maria Orlando; Tucker, Joan S; Stucky, Brian D; Hansen, Mark; Cai, Li
2014-09-01
Nicotine dependence is a core construct important for understanding cigarette smoking and smoking cessation behavior. This article describes analyses conducted to develop and evaluate item banks for assessing nicotine dependence among daily and nondaily smokers. Using data from a sample of daily (N = 4,201) and nondaily (N =1,183) smokers, we conducted a series of item factor analyses, item response theory analyses, and differential item functioning analyses (according to gender, age, and race/ethnicity) to arrive at a unidimensional set of nicotine dependence items for daily and nondaily smokers. We also evaluated performance of short forms (SFs) and computer adaptive tests (CATs) to efficiently assess dependence. A total of 32 items were included in the Nicotine Dependence item banks; 22 items are common across daily and nondaily smokers, 5 are unique to daily smokers, and 5 are unique to nondaily smokers. For both daily and nondaily smokers, the Nicotine Dependence item banks are strongly unidimensional, highly reliable (reliability = 0.97 and 0.97, respectively), and perform similarly across gender, age, and race/ethnicity groups. SFs common to daily and nondaily smokers consist of 8 and 4 items (reliability = 0.91 and 0.81, respectively). Results from simulated CATs showed that dependence can be assessed with very good precision for most respondents using fewer than 6 items adaptively selected from the item banks. Nicotine dependence on cigarettes can be assessed on the basis of these item banks via one of the SFs, by using CATs, or through a tailored set of items selected for a specific research purpose. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Development of the PROMIS negative psychosocial expectancies of smoking item banks.
Stucky, Brian D; Edelen, Maria Orlando; Tucker, Joan S; Shadel, William G; Cerully, Jennifer; Kuhfeld, Megan; Hansen, Mark; Cai, Li
2014-09-01
Negative psychosocial expectancies of smoking include aspects of social disapproval and disappointment in oneself. This paper describes analyses conducted to develop and evaluate item banks for assessing psychosocial expectancies among daily and nondaily smokers. Using data from a sample of daily (N = 4,201) and nondaily (N =1,183) smokers, we conducted a series of item factor analyses, item response theory analyses, and differential item functioning analyses (according to gender, age, and race/ethnicity) to arrive at a unidimensional set of psychosocial expectancies items for daily and nondaily smokers. We also evaluated performance of short forms (SFs) and computer adaptive tests (CATs) to efficiently assess psychosocial expectancies. A total of 21 items were included in the Psychosocial Expectancies item banks: 14 items are common across daily and nondaily smokers, 6 are unique to daily, and 1 is unique to nondaily. For both daily and nondaily smokers, the Psychosocial Expectancies item banks are strongly unidimensional, highly reliable (reliability = 0.95 and 0.93, respectively), and perform similarly across gender, age, and race/ethnicity groups. A SF common to daily and nondaily smokers consists of 6 items (reliability = 0.85). Results from simulated CATs showed that, on average, fewer than 8 items are needed to assess psychosocial expectancies with adequate precision when using the item banks. Psychosocial expectancies of smoking can be assessed on the basis of these item banks via the SF, by using CAT, or through a tailored set of items selected for a specific research purpose. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Hardy, Bruce L.; Kay, Marvin; Marks, Anthony E.; Monigal, Katherine
2001-01-01
Stone tools are often the most abundant type of cultural remains at Paleolithic sites, yet their function is often poorly understood. Investigations of stone tool function, including microscopic use-wear and residue analyses, were performed on a sample of artifacts from the Paleolithic sites of Starosele (40,000–80,000 years BP) and Buran Kaya III (32,000–37,000 years BP). The Middle Paleolithic levels at Starosele exhibit a typical variant of the local Micoquian Industry. The artifacts from Buran Kaya III most closely resemble an Early Streletskayan Industry associated with the early Upper Paleolithic. The results of the functional analyses suggest that hominids at both sites were exploiting woody and starchy plant material as well as birds and mammals. Both sites show evidence of hafting of a wide variety of tools and the possible use of projectile or thrusting spears. These analyses were performed by using two different techniques conducted by independent researchers. Combined residue and use-wear analyses suggest that both the Upper Paleolithic and Middle Paleolithic hominids at these sites were broad-based foragers capable of exploiting a wide range of resources. PMID:11535837
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1993-08-01
Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume of the 1992 PA contains results of uncertainty and sensitivity analyses with respect to migration of gas and brine from the undisturbed repository. Additional information about the 1992 PA is provided in other volumes. Volume 1 containsmore » an overview of WIPP PA and results of a preliminary comparison with 40 CFR 191, Subpart B. Volume 2 describes the technical basis for the performance assessment, including descriptions of the linked computational models used in the Monte Carlo analyses. Volume 3 contains the reference data base and values for input parameters used in consequence and probability modeling. Volume 4 contains uncertainty and sensitivity analyses with respect to the EPA`s Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Finally, guidance derived from the entire 1992 PA is presented in Volume 6. Results of the 1992 uncertainty and sensitivity analyses indicate that, conditional on the modeling assumptions and the assigned parameter-value distributions, the most important parameters for which uncertainty has the potential to affect gas and brine migration from the undisturbed repository are: initial liquid saturation in the waste, anhydrite permeability, biodegradation-reaction stoichiometry, gas-generation rates for both corrosion and biodegradation under inundated conditions, and the permeability of the long-term shaft seal.« less
NASA Technical Reports Server (NTRS)
Hulka, J. R.; Jones, G. W.
2010-01-01
Liquid rocket engines using oxygen and methane propellants are being considered by the National Aeronautics and Space Administration (NASA) for in-space vehicles. This propellant combination has not been previously used in a flight-qualified engine system, so limited test data and analysis results are available at this stage of early development. NASA has funded several hardware-oriented activities with oxygen and methane propellants over the past several years with the Propulsion and Cryogenic Advanced Development (PCAD) project, under the Exploration Technology Development Program. As part of this effort, the NASA Marshall Space Flight Center has conducted combustion, performance, and combustion stability analyses of several of the configurations. This paper summarizes the analyses of combustion and performance as a follow-up to a paper published in the 2008 JANNAF/LPS meeting. Combustion stability analyses are presented in a separate paper. The current paper includes test and analysis results of coaxial element injectors using liquid oxygen and liquid methane or gaseous methane propellants. Several thrust chamber configurations have been modeled, including thrust chambers with multi-element swirl coax element injectors tested at the NASA MSFC, and a uni-element chamber with shear and swirl coax injectors tested at The Pennsylvania State University. Configurations were modeled with two one-dimensional liquid rocket combustion analysis codes, the Rocket Combustor Interaction Design and Analysis (ROCCID), and the Coaxial Injector Combustion Model (CICM). Significant effort was applied to show how these codes can be used to model combustion and performance with oxygen/methane propellants a priori, and what anchoring or calibrating features need to be applied or developed in the future. This paper describes the test hardware configurations, presents the results of all the analyses, and compares the results from the two analytical methods
Yesilbag, D; Eren, M; Agel, H; Kovanlikaya, A; Balci, F
2011-08-01
1. The current study was conducted to evaluate the effects of dietary supplementation with vitamin E (as alpha-tocopherol acetate), dried rosemary leaves and rosemary volatile oil on the performance, meat quality (measured as sensory variables, pH, colour, malondialdehyde (MDA) level, and bacteria count) and serum superoxide dismutase (SOD) activity in broilers fed on maize-soybean meal based diets. 2. A total of 800 broiler chicks were randomly allocated to 8 dietary treatments, which were set up with 1 control group and 7 experimental groups. The control group (VitE1) was given a basal diet including 50 mg/kg alpha-tocopherol acetate, while the experimental groups were given 5 x 7 g/kg rosemary plant (R1), 8 x 6 g/kg plant (R2), 11 x 5 g/kg plant (R3), 100 mg/kg plant oil (RO1), 150 mg/kg plant oil (RO2), 200 mg/kg plant oil (RO3) or 200 mg/kg alpha-tocopherol acetate (VitE2). 3. Although there were no statistical differences observed for feed consumption, other performance variables including live weight gain, feed efficiency and carcase yield were significantly affected. The addition of rosemary volatile oil had more effect on the performance variables than did the rosemary plant itself. 4. As a measure of meat shelf life, TBA analyses were performed on the meat samples on d 1, 3 and 5 after culling. Meat MDA levels of groups fed diets with rosemary and rosemary volatile oil were significantly lower than that of groups fed diets containing alpha-tocopherol acetate alone. 5. Significant differences were also seen between the control and experimental groups for meat colour and meat pH values as well as for sensory analyses. 6. Microbiological analyses conducted at the end of the experiment showed that E. coli counts were significantly reduced in meat samples from the experimental groups. 7. In conclusion, dietary supplementation with rosemary and its volatile oil improved broiler meat quality. Moreover growth performance was positively affected by the rosemary volatile oil supplementations.
Systematic reviews: guidance relevant for studies of older people.
Shenkin, Susan D; Harrison, Jennifer K; Wilkinson, Tim; Dodds, Richard M; Ioannidis, John P A
2017-09-01
Systematic reviews and meta-analyses are increasingly common. This article aims to provide guidance for people conducting systematic reviews relevant to the healthcare of older people. An awareness of these issues will also help people reading systematic reviews to determine whether the results will influence their clinical practice. It is essential that systematic reviews are performed by a team which includes the required technical and clinical expertise. Those performing reviews for the first time should ensure they have appropriate training and support. They must be planned and performed in a transparent and methodologically robust way: guidelines are available. The protocol should be written-and if possible published-before starting the review. Geriatricians will be interested in a table of baseline characteristics, which will help to determine if the studied samples or populations are similar to their patients. Reviews of studies of older people should consider how they will manage issues such as different age cut-offs; non-specific presentations; multiple predictors and outcomes; potential biases and confounders. Systematic reviews and meta-analyses may provide evidence to improve older people's care, or determine where new evidence is required. Newer methodologies, such as meta-analyses of individual level data, network meta-analyses and umbrella reviews, and realist synthesis, may improve the reliability and clinical utility of systematic reviews. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.
NASA Astrophysics Data System (ADS)
Belkerk, B. E.; Soussou, M. A.; Carette, M.; Djouadi, M. A.; Scudeller, Y.
2012-07-01
This paper reports the ultra-fast transient hot-strip (THS) technique for determining the thermal conductivity of thin films and coatings of materials on substrates. The film thicknesses can vary between 10 nm and more than 10 µm. Precise measurement of thermal conductivity was performed with an experimental device generating ultra-short electrical pulses, and subsequent temperature increases were electrically measured on nanosecond and microsecond time scales. The electrical pulses were applied within metallized micro-strips patterned on the sample films and the temperature increases were analysed within time periods selected in the window [100 ns-10 µs]. The thermal conductivity of the films was extracted from the time-dependent thermal impedance of the samples derived from a three-dimensional heat diffusion model. The technique is described and its performance demonstrated on different materials covering a large thermal conductivity range. Experiments were carried out on bulk Si and thin films of amorphous SiO2 and crystallized aluminum nitride (AlN). The present approach can assess film thermal resistances as low as 10-8 K m2 W-1 with a precision of about 10%. This has never been attained before with the THS technique.
Evolution of thermo-physical properties and annealing of fast neutron irradiated boron carbide
NASA Astrophysics Data System (ADS)
Gosset, Dominique; Kryger, Bernard; Bonal, Jean-Pierre; Verdeau, Caroline; Froment, Karine
2018-03-01
Boron carbide is widely used as a neutron absorber in most nuclear reactors, in particular in fast neutron ones. The irradiation leads to a large helium production (up to 1022/cm3) together with a strong decrease of the thermal conductivity. In this paper, we have performed thermal diffusivity measurements and X-ray diffraction analyses on boron carbide samples coming from control rods of the French Phenix LMFBR reactor. The burnups range from 1021 to 8.1021/cm3. We first confirm the strong decrease of the thermal conductivity at the low burnup, together with high microstructural modifications: swelling, large micro-strains, high defects density, and disordered-like material conductivity. We observe the microstructural parameters are highly anisotropic, with high micro-strains and flattened coherent diffracting domains along the (00l) direction of the hexagonal structure. Performing heat treatments up to high temperature (2200 °C) allows us to observe the material thermal conductivity and microstructure restoration. It then appears the thermal conductivity healing is correlated to the micro-strain relaxation. We then assume the defects responsible for most of the damage are the helium bubbles and the associated stress fields.
A decision model for cost effective design of biomass based green energy supply chains.
Yılmaz Balaman, Şebnem; Selim, Hasan
2015-09-01
The core driver of this study is to deal with the design of anaerobic digestion based biomass to energy supply chains in a cost effective manner. In this concern, a decision model is developed. The model is based on fuzzy multi objective decision making in order to simultaneously optimize multiple economic objectives and tackle the inherent uncertainties in the parameters and decision makers' aspiration levels for the goals. The viability of the decision model is explored with computational experiments on a real-world biomass to energy supply chain and further analyses are performed to observe the effects of different conditions. To this aim, scenario analyses are conducted to investigate the effects of energy crop utilization and operational costs on supply chain structure and performance measures. Copyright © 2015 Elsevier Ltd. All rights reserved.
Effects of heat-treatment and explosive brisance on fragmentation of high strength steel
NASA Astrophysics Data System (ADS)
Stolken, James; Kumar, Mukul; Gold, Vladimir; Baker, Ernest; Lawrence Livermore Nationa Laboratory Collaboration; Armament Research Development; Eng Collaboration
2011-06-01
Tubes of AISI-4340 steel were heat-treated to three distinct microstructures resulting in nominal hardness values of 25 Rc, 38 Rc and 48 Rc. The specimens were then explosively fragmented using TNT and PETN. The experiments were conducted in a contained firing facility with high fragment collection efficiency. Statistical analyses of recovered fragments were performed. Fragment rank-order statistics and generalized goodness-of-fit tests were used to characterize the fragment mass distributions. These analyses indicated significant interaction effects between the heat-treatment (and the resulting microstructure) and the explosive brisance. The role of the microstructure in relation to the yield-strength and toughness will also be discussed. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
Skordis-Worrall, Jolene; Manandhar, Dharma S.; Strachan, Daniel; Morrison, Joanna; Saville, Naomi; Osrin, David; Tumbahangphe, Kirti M.; Costello, Anthony; Heys, Michelle
2018-01-01
Women’s groups practicing participatory learning and action (PLA) in rural areas have been shown to improve maternal and newborn survival in low-income countries, but the pathways from intervention to impact remain unclear. We assessed the long-term impact of a PLA intervention in rural Nepal on women’s agency in the household. In 2014, we conducted a follow-up study to a cluster randomised controlled trial on the impact of PLA women’s groups from 2001–2003. Agency was measured using the Relative Autonomy Index (RAI) and its subdomains. Multi-level regression analyses were performed adjusting for baseline socio-demographic characteristics. We additionally adjusted for potential exposure to subsequent PLA groups based on women’s pregnancy status and conduct of PLA groups in areas of residence. Sensitivity analyses were performed using two alternative measures of agency. We analysed outcomes for 4030 mothers (66% of the cohort) who survived and were recruited to follow-up at mean age 39.6 years. Across a wide range of model specifications, we found no association between exposure to the original PLA intervention with women’s agency in the household approximately 11.5 years later. Subsequent exposure to PLA groups was not associated with greater agency in the household at follow-up, but some specifications found evidence for reduced agency. Household agency may be a prerequisite for actualising the benefits of PLA groups rather than a consequence. PMID:29758071
The Child Adolescent Bullying Scale (CABS): Psychometric evaluation of a new measure.
Strout, Tania D; Vessey, Judith A; DiFazio, Rachel L; Ludlow, Larry H
2018-06-01
While youth bullying is a significant public health problem, healthcare providers have been limited in their ability to identify bullied youths due to the lack of a reliable, and valid instrument appropriate for use in clinical settings. We conducted a multisite study to evaluate the psychometric properties of a new 22-item instrument for assessing youths' experiences of being bullied, the Child Adolescent Bullying Scale (CABS). The 20 items summed to produce the measure's score were evaluated here. Diagnostic performance was assessed through evaluation of sensitivity, specificity, predictive values, and area under receiver operating characteristic (AUROC) curve. A sample of 352 youths from diverse racial, ethnic, and geographic backgrounds (188 female, 159 male, 5 transgender, sample mean age 13.5 years) were recruited from two clinical sites. Participants completed the CABS and existing youth bullying measures. Analyses grounded in classical test theory, including assessments of reliability and validity, item analyses, and principal components analysis, were conducted. The diagnostic performance and test characteristics of the CABS were also evaluated. The CABS is comprised of one component, accounting for 67% of observed variance. Analyses established evidence of internal consistency reliability (Cronbach's α = 0.97), construct and convergent validity. Sensitivity was 84%, specificity was 65%, and the AUROC curve was 0.74 (95% CI: 0.69-0.80). Findings suggest that the CABS holds promise as a reliable, valid tool for healthcare provider use in screening for bullying exposure in the clinical setting. © 2018 Wiley Periodicals, Inc.
Escobar, Gabriel J; Baker, Jennifer M; Turk, Benjamin J; Draper, David; Liu, Vincent; Kipnis, Patricia
2017-01-01
This article is not a traditional research report. It describes how conducting a specific set of benchmarking analyses led us to broader reflections on hospital benchmarking. We reexamined an issue that has received far less attention from researchers than in the past: How variations in the hospital admission threshold might affect hospital rankings. Considering this threshold made us reconsider what benchmarking is and what future benchmarking studies might be like. Although we recognize that some of our assertions are speculative, they are based on our reading of the literature and previous and ongoing data analyses being conducted in our research unit. We describe the benchmarking analyses that led to these reflections. The Centers for Medicare and Medicaid Services' Hospital Compare Web site includes data on fee-for-service Medicare beneficiaries but does not control for severity of illness, which requires physiologic data now available in most electronic medical records.To address this limitation, we compared hospital processes and outcomes among Kaiser Permanente Northern California's (KPNC) Medicare Advantage beneficiaries and non-KPNC California Medicare beneficiaries between 2009 and 2010. We assigned a simulated severity of illness measure to each record and explored the effect of having the additional information on outcomes. We found that if the admission severity of illness in non-KPNC hospitals increased, KPNC hospitals' mortality performance would appear worse; conversely, if admission severity at non-KPNC hospitals' decreased, KPNC hospitals' performance would appear better. Future hospital benchmarking should consider the impact of variation in admission thresholds.
Tarride, Jean-Eric; Goeree, Ron; Lokker, Cynthia; McKibbon, K Ann
2011-01-01
Objective To conduct a systematic review and synthesis of the evidence surrounding the cost-effectiveness of health information technology (HIT) in the medication process. Materials and methods Peer-reviewed electronic databases and gray literature were searched to identify studies on HIT used to assist in the medication management process. Articles including an economic component were reviewed for further screening. For this review, full cost-effectiveness analyses, cost-utility analyses and cost-benefit analyses, as well as cost analyses, were eligible for inclusion and synthesis. Results The 31 studies included were heterogeneous with respect to the HIT evaluated, setting, and economic methods used. Thus the data could not be synthesized, and a narrative review was conducted. Most studies evaluated computer decision support systems in hospital settings in the USA, and only five of the studied performed full economic evaluations. Discussion Most studies merely provided cost data; however, useful economic data involves far more input. A full economic evaluation includes a full enumeration of the costs, synthesized with the outcomes of the intervention. Conclusion The quality of the economic literature in this area is poor. A few studies found that HIT may offer cost advantages despite their increased acquisition costs. However, given the uncertainty that surrounds the costs and outcomes data, and limited study designs, it is difficult to reach any definitive conclusion as to whether the additional costs and benefits represent value for money. Sophisticated concurrent prospective economic evaluations need to be conducted to address whether HIT interventions in the medication management process are cost-effective. PMID:21984590
Dong, Qing; Liu, Hua; Yang, Daren; Zhang, Yunyan
2017-05-01
Investigators have explored the association between diabetes mellitus and arthritis for a long time; however, there are uncertainties and inconsistencies among various studies. In this study, we tried to explore the relationship between diabetes mellitus and the overall risk of arthritis, as well as the potential modifiers for this relationship. We conducted a comprehensive literature search through PubMed and identified 36 eligible studies. The overall analyses, subgroup analyses, as well as sensitivity analyses, were conducted to illustrate the association between diabetes mellitus and arthritis. Study quality was evaluated using the Newcastle-Ottawa Quality Assessment Scale. All statistical analyses were conducted using STATA SE version 13.0. In our study, 36 eligible studies were identified and involved in the meta-analysis. The overall association between diabetes mellitus and arthritis is 1.61 (95% confidence interval [CI]: 1.14-2.28, P = .007). The association exists only in nongouty arthritis, where we observed the estimated odds ratio (OR) 1.33 (95% CI: 1.05-1.67, P < .001). The opposite point estimates from different types of diabetes may indicate possible different associations for type I (OR: 0.98, 95% CI: 0.18-5.39, P = .985) or type II diabetes (OR: 1.28, 95% CI: 0.88-1.84, P = .194). Diabetes mellitus performs more likely as a comorbidity of arthritis rather than a risk factor; however, more studies will be helpful to increase the confidence of identifying the association between diabetes and arthritis.
NASA Astrophysics Data System (ADS)
Kahveci, Ajda; Kahveci, Murat; Mansour, Nasser; Alarfaj, Maher Mohammed
2017-06-01
Teachers play a key role in moving reform-based science education practices into the classroom. Based on research that emphasizes the importance of teachers' affective states, this study aimed to explore the constructs pedagogical discontentment, science teaching self-efficacy, intentions to reform, and their correlations. Also, it aimed to provide empirical evidence in light of a previously proposed theoretical model while focusing on an entirely new context in Middle East. Data were collected in Saudi Arabia with a total of randomly selected 994 science teachers, 656 of whom were females and 338 were males. To collect the data, the Arabic versions of the Science Teachers' Pedagogical Discontentment scale, the Science Teaching Efficacy Beliefs Instrument and the Intentions to Reform Science Teaching scale were developed. For assuring the validity of the instruments in a non-Western context, rigorous cross-cultural validations procedures were followed. Factor analyses were conducted for construct validation and descriptive statistical analyses were performed including frequency distributions and normality checks. Univariate analyses of variance were run to explore statistically significant differences between groups of teachers. Cross-tabulation and correlation analyses were conducted to explore relationships. The findings suggest effect of teacher characteristics such as age and professional development program attendance on the affective states. The results demonstrate that teachers who attended a relatively higher number of programs had lower level of intentions to reform raising issues regarding the conduct and outcomes of professional development. Some of the findings concerning interrelationships among the three constructs challenge and serve to expand the previously proposed theoretical model.
Rongeat, Carine; Reddy, M Anji; Witter, Raiker; Fichtner, Maximilian
2014-02-12
Batteries based on a fluoride shuttle (fluoride ion battery, FIB) can theoretically provide high energy densities and can thus be considered as an interesting alternative to Li-ion batteries. Large improvements are still needed regarding their actual performance, in particular for the ionic conductivity of the solid electrolyte. At the current state of the art, two types of fluoride families can be considered for electrolyte applications: alkaline-earth fluorides having a fluorite-type structure and rare-earth fluorides having a tysonite-type structure. As regard to the latter, high ionic conductivities have been reported for doped LaF3 single crystals. However, polycrystalline materials would be easier to implement in a FIB due to practical reasons in the cell manufacturing. Hence, we have analyzed in detail the ionic conductivity of La(1-y)Ba(y)F(3-y) (0 ≤ y ≤ 0.15) solid solutions prepared by ball milling. The combination of DC and AC conductivity analyses provides a better understanding of the conduction mechanism in tysonite-type fluorides with a blocking effect of the grain boundaries. Heat treatment of the electrolyte material was performed and leads to an improvement of the ionic conductivity. This confirms the detrimental effect of grain boundaries and opens new route for the development of solid electrolytes for FIB with high ionic conductivities.
IN SITU FIELD TESTING OF PROCESSES
DOE Office of Scientific and Technical Information (OSTI.GOV)
J.S.Y. YANG
2004-11-08
The purpose of this scientific analysis report is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts and surface-based boreholes through unsaturated zone (UZ) tuff rock units. In situ testing, monitoring, and associated laboratory studies are conducted to directly assess and evaluate the waste emplacement environment and the natural barriers to radionuclide transport at Yucca Mountain. This scientific analysis report supports and provides data to UZ flow and transport model reports, which in turn contribute to the Total System Performance Assessment (TSPA) of Yucca Mountain, an important document for the license applicationmore » (LA). The objectives of ambient field-testing activities are described in Section 1.1. This report is the third revision (REV 03), which supercedes REV 02. The scientific analysis of data for inputs to model calibration and validation as documented in REV 02 were developed in accordance with the Technical Work Plan (TWP) ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (BSC 2004 [DIRS 167969]). This revision was developed in accordance with the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.4) for better integrated, consistent, transparent, traceable, and more complete documentation in this scientific analysis report and associated UZ flow and transport model reports. No additional testing or analyses were performed as part of this revision. The list of relevant acceptance criteria is provided by ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654]), Table 3-1. Additional deviations from the TWP regarding the features, events, and processes (FEPs) list are discussed in Section 1.3. Documentation in this report includes descriptions of how, and under what conditions, the tests were conducted. The descriptions and analyses provide data useful for refining and confirming the understanding of flow, drift seepage, and transport processes in the UZ. The UZ testing activities included measurement of permeability distribution, quantification of the seepage of water into the drifts, evaluation of fracture-matrix interaction, study of flow along faults, testing of flow and transport between drifts, characterization of hydrologic heterogeneity along drifts, estimation of drying effects on the rock surrounding the drifts due to ventilation, monitoring of moisture conditions in open and sealed drifts, and determination of the degree of minimum construction water migration below drift. These field tests were conducted in two underground drifts at Yucca Mountain, the Exploratory Studies Facility (ESF) drift, and the cross-drift for Enhanced Characterization of the Repository Block (ECRB), as described in Section 1.2. Samples collected in boreholes and underground drifts have been used for additional hydrochemical and isotopic analyses for additional understanding of the UZ setting. The UZ transport tests conducted at the nearby Busted Butte site (see Figure 1-4) are also described in this scientific analysis report.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bucknor, Matthew; Hu, Rui; Lisowski, Darius
2016-04-17
The Reactor Cavity Cooling System (RCCS) is an important passive safety system being incorporated into the overall safety strategy for high temperature advanced reactor concepts such as the High Temperature Gas- Cooled Reactors (HTGR). The Natural Convection Shutdown Heat Removal Test Facility (NSTF) at Argonne National Laboratory (Argonne) reflects a 1/2-scale model of the primary features of one conceptual air-cooled RCCS design. The project conducts ex-vessel, passive heat removal experiments in support of Department of Energy Office of Nuclear Energy’s Advanced Reactor Technology (ART) program, while also generating data for code validation purposes. While experiments are being conducted at themore » NSTF to evaluate the feasibility of the passive RCCS, parallel modeling and simulation efforts are ongoing to support the design, fabrication, and operation of these natural convection systems. Both system-level and high fidelity computational fluid dynamics (CFD) analyses were performed to gain a complete understanding of the complex flow and heat transfer phenomena in natural convection systems. This paper provides a summary of the RELAP5-3D NSTF model development efforts and provides comparisons between simulation results and experimental data from the NSTF. Overall, the simulation results compared favorably to the experimental data, however, further analyses need to be conducted to investigate any identified differences.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-24
... methodological issues that arise in the use of meta-analyses to evaluate safety risks, followed by a discussion... design, conduct and use of meta-analysis. Although many external stakeholders conduct meta-analyses, FDA... meeting. FDA expects that this meeting will build upon prior stakeholder feedback on the design, conduct...
Rheological Analysis of Live and Dead Microalgae Suspensions
NASA Astrophysics Data System (ADS)
Song, Young Seok; Kang, Chul; Jeong, Jiwon; Kim, Kyu-Oh; Lim, Eunju
2018-04-01
We investigate the rheological properties of microalgae suspensions that are currently being used in various applications. Two kinds of microalgae, chlorella and Synechococcus, were used for preparation of the suspensions, and their rheological characteristics were analyzed experimentally. In order to evaluate the viability of algae, we performed live and dead tests using trypan blue staining assays. Morphological analyses for the algae were conducted using a scanning electron microscope (SEM) and an optical microscope (OP). We examined the viscoelastic behavior of the live and the dead algae suspensions by performing dynamic oscillatory shear tests.
NASA Technical Reports Server (NTRS)
Mellish, J. A.
1979-01-01
The performance optimization of expander cycle engines at vacuum thrust levels of 10K, 15K, and 20K lb is discussed. The optimization is conducted for a maximum engine length with an extendible nozzle in the retracted position of 60 inches and an engine mixture ratio of 6.0:1. The thrust chamber geometry and cycle analyses are documented. In addition, the sensitivity of a recommended baseline expander cycle to component performance variations is determined and chilldown/start propellant consumptions are estimated.
2011-02-11
on TF39 engines, which are typically used for C-5 Galaxy aircraft; T56 engines, which are typically used for C-130 aircraft; and fuel accessories on...conducting separate cost-benefit analyses for the TF39 and T56 engine maintenance work. Under Air Force guidance for depot-level source-of-repair selection...Force has not developed specific risk mitigation plans for the TF39 or T56 engines because it is still assessing how the work will be performed
Performance of a 1-micron, 1-joule Coherent Launch Site Atmospheric Wind Sounder
NASA Technical Reports Server (NTRS)
Hawley, James G.; Targ, Russell; Bruner, Richard; Henderson, Sammy W.; Hale, Charles P.; Vetorino, Steven; Lee, R. W.; Harper, Scott; Khan, Tayyab
1992-01-01
The paper describes the design and performance of the Coherent Launch Site Atmospheric Wind Sounder (CLAWS), which is a test and demonstration program designed for monitoring winds with a solid-state lidar in real time for the launch site vehicle guidance and control application. Analyses were conducted to trade off CO2 (9.11- and 10.6-microns), Ho:YAG (2.09 microns), and Nd:YAG (1.06-micron) laser-based lidars. The measurements set a new altitude record (26 km) for coherent wind measurements in the stratosphere.
[Difficulties in learning mathematics].
Rebollo, M A; Rodríguez, A L
2006-02-13
To discuss our concern for some aspects of mathematics learning disorders related to the nomenclature employed and their diagnosis; these aspects refer to the term 'dyscalculia' and to its diagnosis (especially syndromatic diagnosis). We also intend to propose a classification that could help to define the terminology. Lastly we are going to consider the different aspects of diagnosis and to determine which of them are indispensable in the diagnosis of primary and secondary disorders. As far as the nomenclature is concerned, we refer to the term 'dyscalculia'. The origins of the term are analysed along with the reasons why it should not be used in children with difficulties in learning mathematics. We propose a classification and denominations for the different types that should undoubtedly be discussed. With respect to the diagnosis, several problems related to the syndromatic diagnosis are considered, since in our country there are no standardised tests with which to study performance in arithmetic and geometry. This means that criterion reference tests are conducted to try to establish current and potential performance. At this stage of the diagnosis pedagogical and psychological studies must be conducted. The important factors with regard to the topographical and aetiological diagnoses are prior knowledge, results from the studies that have been carried out and findings from imaging studies. The importance of a genetic study must be defined in the aetiological diagnosis. We propose a nomenclature to replace the term 'dyscalculia'. Standardised tests are needed for the diagnosis. The need to establish current and potential performance is hierarchized. With regard to the topographical diagnosis, we highlight the need for more information about geometry, and in aetiological studies the analyses must be conducted with greater numbers of children.
Trajectory-based heating analysis for the European Space Agency/Rosetta Earth Return Vehicle
NASA Technical Reports Server (NTRS)
Henline, William D.; Tauber, Michael E.
1994-01-01
A coupled, trajectory-based flowfield and material thermal-response analysis is presented for the European Space Agency proposed Rosetta comet nucleus sample return vehicle. The probe returns to earth along a hyperbolic trajectory with an entry velocity of 16.5 km/s and requires an ablative heat shield on the forebody. Combined radiative and convective ablating flowfield analyses were performed for the significant heating portion of the shallow ballistic entry trajectory. Both quasisteady ablation and fully transient analyses were performed for a heat shield composed of carbon-phenolic ablative material. Quasisteady analysis was performed using the two-dimensional axisymmetric codes RASLE and BLIMPK. Transient computational results were obtained from the one-dimensional ablation/conduction code CMA. Results are presented for heating, temperature, and ablation rate distributions over the probe forebody for various trajectory points. Comparison of transient and quasisteady results indicates that, for the heating pulse encountered by this probe, the quasisteady approach is conservative from the standpoint of predicted surface recession.
Structural dynamics of shroudless, hollow fan blades with composite in-lays
NASA Technical Reports Server (NTRS)
Aiello, R. A.; Hirschbein, M. S.; Chamis, C. C.
1982-01-01
Structural and dynamic analyses are presented for a shroudless, hollow titanium fan blade proposed for future use in aircraft turbine engines. The blade was modeled and analyzed using the composite blade structural analysis computer program (COBSTRAN); an integrated program consisting of mesh generators, composite mechanics codes, NASTRAN, and pre- and post-processors. Vibration and impact analyses are presented. The vibration analysis was conducted with COBSTRAN. Results show the effect of the centrifugal force field on frequencies, twist, and blade camber. Bird impact analysis was performed with the multi-mode blade impact computer program. This program uses the geometric model and modal analysis from the COBSTRAN vibration analysis to determine the gross impact response of the fan blades to bird strikes. The structural performance of this blade is also compared to a blade of similar design but with composite in-lays on the outer surface. Results show that the composite in-lays can be selected (designed) to substantially modify the mechanical performance of the shroudless, hollow fan blade.
Mohammad Shiri, Hamid; Ehsani, Ali; Jalali Khales, Mina
2017-11-01
A novel electrosynthetic method was introduced to synthesize of Sm 2 O 3 nanoparticles and furthermore, for improving the electrochemical performance of conductive polymer, hybrid POAP/Sm 2 O 3 films have then been fabricated by POAP electropolymerization in the presence of Sm 2 O 3 nanoparticles as active electrodes for electrochemical supercapacitors. The structure, morphology, chemical composition of Sm 2 O 3 nanoparticles was examined. Surface and electrochemical analyses have been used for characterization of Sm 2 O 3 and POAP/Sm 2 O 3 composite films. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. The supercapacity behavior of the composite film was attributed to the (i) high active surface area of the composite, (ii) charge transfer along the polymer chain due to the conjugation form of the polymer and finally (iii) synergism effect between conductive polymer and Sm 2 O 3 nanoparticles. Copyright © 2017 Elsevier Inc. All rights reserved.
A computer program for geochemical analysis of acid-rain and other low-ionic-strength, acidic waters
Johnsson, P.A.; Lord, D.G.
1987-01-01
ARCHEM, a computer program written in FORTRAN 77, is designed primarily for use in the routine geochemical interpretation of low-ionic-strength, acidic waters. On the basis of chemical analyses of the water, and either laboratory or field determinations of pH, temperature, and dissolved oxygen, the program calculates the equilibrium distribution of major inorganic aqueous species and of inorganic aluminum complexes. The concentration of the organic anion is estimated from the dissolved organic concentration. Ionic ferrous iron is calculated from the dissolved oxygen concentration. Ionic balances and comparisons of computed with measured specific conductances are performed as checks on the analytical accuracy of chemical analyses. ARCHEM may be tailored easily to fit different sampling protocols, and may be run on multiple sample analyses. (Author 's abstract)
Faggion, Clovis Mariano; Wu, Yun-Chun; Scheidgen, Moritz; Tu, Yu-Kang
2015-01-01
Background Risk of bias (ROB) may threaten the internal validity of a clinical trial by distorting the magnitude of treatment effect estimates, although some conflicting information on this assumption exists. Objective The objective of this study was evaluate the effect of ROB on the magnitude of treatment effect estimates in randomized controlled trials (RCTs) in periodontology and implant dentistry. Methods A search for Cochrane systematic reviews (SRs), including meta-analyses of RCTs published in periodontology and implant dentistry fields, was performed in the Cochrane Library in September 2014. Random-effect meta-analyses were performed by grouping RCTs with different levels of ROBs in three domains (sequence generation, allocation concealment, and blinding of outcome assessment). To increase power and precision, only SRs with meta-analyses including at least 10 RCTs were included. Meta-regression was performed to investigate the association between ROB characteristics and the magnitudes of intervention effects in the meta-analyses. Results Of the 24 initially screened SRs, 21 SRs were excluded because they did not include at least 10 RCTs in the meta-analyses. Three SRs (two from periodontology field) generated information for conducting 27 meta-analyses. Meta-regression did not reveal significant differences in the relationship of the ROB level with the size of treatment effect estimates, although a trend for inflated estimates was observed in domains with unclear ROBs. Conclusion In this sample of RCTs, high and (mainly) unclear risks of selection and detection biases did not seem to influence the size of treatment effect estimates, although several confounders might have influenced the strength of the association. PMID:26422698
NASA Technical Reports Server (NTRS)
Soulas, George C.; Patterson, Michael J.; Herman, Daniel A.
2009-01-01
The NASA s Evolutionary Xenon Thruster (NEXT) program is developing the next-generation ion propulsion system with significant enhancements beyond the state-of-the-art in ion propulsion to provide future NASA science missions with enhanced mission capabilities at a low total development cost. As part of a comprehensive thruster service life assessment utilizing both testing and analyses, a Long-Duration Test (LDT) was initiated to verify the NEXT propellant throughput capability to a qualification-level of 450 kg, 1.5 times the anticipated throughput requirement of 300 kg from mission analyses conducted utilizing the NEXT propulsion system. The LDT is being conducted with a modified, flight-representative NEXT engineering model ion thruster, designated EM3. As of June 25, 2008, the thruster has accumulated 16,550 h of operation: the first 13,042 h at the thruster full-input-power of 6.9 kW with 3.52 A beam current and 1800 V beam power supply voltage. Operation since 13,042 h, i.e., the most recent 3,508 h, has been at an input power of 4.7 kW with 3.52 A beam current and 1180 V beam power supply voltage. The thruster has processed 337 kg of xenon (Xe) surpassing the NSTAR propellant throughput demonstrated during the extended life testing of the Deep Space 1 flight spare ion thruster. The NEXT LDT has demonstrated a total impulse of 13.3 106 N s; the highest total impulse ever demonstrated by an ion thruster. Thruster performance tests are conducted periodically over the entire NEXT throttle table with input power ranging 0.5 to 6.9 kW. Thruster performance parameters including thrust, input power, specific impulse, and thruster efficiency have been nominal with little variation to date. This paper presents the performance of the NEXT LDT to date with emphasis on performance variations following throttling of the thruster to the new operating condition and comparison of performance to the NSTAR extended life test.
ERIC Educational Resources Information Center
Ronnlund, Michael; Nilsson, Lars-Goran.
2009-01-01
The study examined the extent to which time-related gains in cognitive performance, so-called Flynn effects, generalize across sub-factors of episodic memory (recall and recognition) and semantic memory (knowledge and fluency). We conducted time-sequential analyses of data drawn from the Betula prospective cohort study, involving four age-matched…
THE EPA and NSF verified the performance of the ClorTec Model MC100 System under the EPA's ETV program. The concentrated hypochlorite generator stream from the treatment system underwent a twice-daily analysis from 3/8-4/6/00. The chlorine analyses were conducted onsite in United...
Al-26 losses from weathered chondrites
NASA Technical Reports Server (NTRS)
Herzog, G. F.; Cressy, P. J., Jr.
1976-01-01
Analysis of Al-26 and noble gases were conducted in a study of samples of two heavily weathered meteorites. The analyses were performed in accordance with procedures described by Cressy (1970) and by Herzog and Cressy (1974). The analytic data are presented in tables. Evidence is presented which implicates weathering as the most probable cause of the observed variation of Al-26 and the rare gas contents.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-04-15
This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Oliktok Point radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.
ERIC Educational Resources Information Center
King, Keith A.; Merianos, Ashley L.; Vidourek, Rebecca A.; Oluwoye, Oladunni A.
2017-01-01
The study purpose was to examine the relationship between sports participation and recent alcohol and past-year alcohol use among students. A secondary data analysis of the PRIDE survey (N = 37,616) was performed. A series of chi-square analyses and odds ratios were conducted. Results indicated sports participation reduced the odds for past-year…
Mammographic Breast Density in a Cohort of Medically Underserved Women
2012-10-01
training, faculty from MMC and VUMC will conduct a case-control study of mammographic breast density to investigate its’ association with obesity and...hormones and growth factors, 4) to perform statistical analyses to determine the associations between obesity and insulin resistance and mammographic...on obesity and insulin resistance as they relate to mammographic breast density. We hypothesize that: 1) obesity and insulin resistance, defined
ERIC Educational Resources Information Center
Kaljee, Linda M.; Green, Mackenzie S.; Zhan, Min; Riel, Rosemary; Lerdboon, Porntip; Lostutter, Ty W.; Tho, Le Huu; Luong, Vo Van; Minh, Truong Tan
2011-01-01
A randomly selected cross-sectional survey was conducted with 880 youth (16 to 24 years) in Nha Trang City to assess relationships between alcohol consumption and sexual behaviors. A timeline followback method was employed. Chi-square, generalized logit modeling and logistic regression analyses were performed. Of the sample, 78.2% male and 56.1%…
ERIC Educational Resources Information Center
Seal, David Wyatt; Belcher, Lisa; Morrow, Kathleen; Eldridge, Gloria; Binson, Diane; Kacanek, Deborah; Margolis, Andrew D.; McAuliffe, Tim; Simms, Rodney
2004-01-01
The article describes men's perceptions of and experience with substance use and sexual behavior during incarceration. Grounded theory content analyses were performed on qualitative interviews conducted with 80 men, aged 18 to 29, in four U.S. states. Participants believed that drugs were easily available in prison. Half reported using substances,…
Houck, Darby A; Kraeutler, Matthew J; Schuette, Hayden B; McCarty, Eric C; Bravman, Jonathan T
2017-10-01
Previous meta-analyses have been conducted to compare outcomes of early versus delayed motion after rotator cuff repair. To conduct a systematic review of overlapping meta-analyses comparing early versus delayed motion rehabilitation protocols after rotator cuff repair to determine which meta-analyses provide the best available evidence. Systematic review. A systematic review was performed by searching PubMed and Cochrane Library databases. Search terms included "rotator cuff repair," "early passive motion," "immobilization," "rehabilitation protocol," and "meta-analysis." Results were reviewed to determine study eligibility. Patient outcomes and structural healing were extracted from these meta-analyses. Meta-analysis quality was assessed using the Oxman-Guyatt and Quality of Reporting of Meta-analyses (QUOROM) systems. The Jadad decision algorithm was then used to determine which meta-analyses provided the best level of evidence. Seven meta-analyses containing a total of 5896 patients met the eligibility criteria (1 Level I evidence, 4 Level II evidence, 2 Level III evidence). None of these meta-analyses found immobilization to be superior to early motion; however, most studies suggested that early motion would increase range of motion (ROM), thereby reducing time of recovery. Three of these studies suggested that tear size contributed to the choice of rehabilitation to ensure proper healing of the shoulder. A study by Chan et al in 2014 received the highest QUOROM and Oxman-Guyatt scores, and therefore this meta-analysis appeared to have the highest level of evidence. Additionally, a study by Riboh and Garrigues in 2014 was selected as the highest quality study in this systematic review according to the Jadad decision algorithm. The current, best available evidence suggests that early motion improves ROM after rotator cuff repair but increases the risk of rotator cuff retear. Lower quality meta-analyses indicate that tear size may provide a better strategy in determining the correct rehabilitation protocol.
NASA Astrophysics Data System (ADS)
Nakamura, D.; Altarawneh, M. M.; Takeyama, S.
2018-03-01
A contactless measurement system of electrical conductivity was developed for application under pulsed high magnetic fields over 100 T by using a self-resonant-type, high-frequency circuit. Electromagnetic fields in the circuit were numerically analysed by the finite element method, to show how the resonant power spectra of the circuit depends on the electrical conductivity of a sample set on the probe-coil. The performance was examined using a high-temperature cuprate superconductor, La2-x Sr x CuO4, in magnetic fields up to 102 T with a high frequency of close to 800 MHz. As a result, the upper critical field could be determined with a good signal-to-noise ratio.
Toh, Sengwee; Gagne, Joshua J; Rassen, Jeremy A; Fireman, Bruce H; Kulldorff, Martin; Brown, Jeffrey S
2013-08-01
A distributed research network (DRN) of electronic health care databases, in which data reside behind the firewall of each data partner, can support a wide range of comparative effectiveness research (CER) activities. An essential component of a fully functional DRN is the capability to perform robust statistical analyses to produce valid, actionable evidence without compromising patient privacy, data security, or proprietary interests. We describe the strengths and limitations of different confounding adjustment approaches that can be considered in observational CER studies conducted within DRNs, and the theoretical and practical issues to consider when selecting among them in various study settings. Several methods can be used to adjust for multiple confounders simultaneously, either as individual covariates or as confounder summary scores (eg, propensity scores and disease risk scores), including: (1) centralized analysis of patient-level data, (2) case-centered logistic regression of risk set data, (3) stratified or matched analysis of aggregated data, (4) distributed regression analysis, and (5) meta-analysis of site-specific effect estimates. These methods require different granularities of information be shared across sites and afford investigators different levels of analytic flexibility. DRNs are growing in use and sharing of highly detailed patient-level information is not always feasible in DRNs. Methods that incorporate confounder summary scores allow investigators to adjust for a large number of confounding factors without the need to transfer potentially identifiable information in DRNs. They have the potential to let investigators perform many analyses traditionally conducted through a centralized dataset with detailed patient-level information.
Viscous Design of TCA Configuration
NASA Technical Reports Server (NTRS)
Krist, Steven E.; Bauer, Steven X. S.; Campbell, Richard L.
1999-01-01
The goal in this effort is to redesign the baseline TCA configuration for improved performance at both supersonic and transonic cruise. Viscous analyses are conducted with OVERFLOW, a Navier-Stokes code for overset grids, using PEGSUS to compute the interpolations between overset grids. Viscous designs are conducted with OVERDISC, a script which couples OVERFLOW with the Constrained Direct Iterative Surface Curvature (CDISC) inverse design method. The successful execution of any computational fluid dynamics (CFD) based aerodynamic design method for complex configurations requires an efficient method for regenerating the computational grids to account for modifications to the configuration shape. The first section of this presentation deals with the automated regridding procedure used to generate overset grids for the fuselage/wing/diverter/nacelle configurations analysed in this effort. The second section outlines the procedures utilized to conduct OVERDISC inverse designs. The third section briefly covers the work conducted by Dick Campbell, in which a dual-point design at Mach 2.4 and 0.9 was attempted using OVERDISC; the initial configuration from which this design effort was started is an early version of the optimized shape for the TCA configuration developed by the Boeing Commercial Airplane Group (BCAG), which eventually evolved into the NCV design. The final section presents results from application of the Natural Flow Wing design philosophy to the TCA configuration.
Broughton, Mary C.; Davidson, Jane W.
2014-01-01
Self-reflective performance review and expert evaluation are features of Western music performance practice. While music is usually the focus, visual information provided by performing musicians’ expressive bodily behaviors communicates expressiveness to musically trained and untrained observers. Yet, within a seemingly homogenous group, such as one of musically trained individuals, diversity of experience exists. Individual differences potentially affect perception of the subtleties of expressive performance, and performers’ effective communication of their expressive intentions. This study aimed to compare self- and other expert musicians’ perception of expressive bodily behaviors observed in marimba performance. We hypothesized that analyses of expressive bodily behaviors differ between expert musicians according to their specialist motor expertise and familiarity with the music. Two professional percussionists and experienced marimba players, and one professional classical singer took part in the study. Participants independently conducted Laban effort-shape analysis – proposing that intentions manifest in bodily activity are understood through shared embodied processes – of a marimbists’ expressive bodily behaviors in an audio-visual performance recording. For one percussionist, this was a self-reflective analysis. The work was unfamiliar to the other percussionist and singer. Perception of the performer’s expressive bodily behaviors appeared to differ according to participants’ individual instrumental or vocal motor expertise, and familiarity with the music. Furthermore, individual type of motor experience appeared to direct participants’ attention in approaching the analyses. Findings support forward and inverse perception–action models, and embodied cognitive theory. Implications offer scientific rigor and artistic interest for how performance practitioners can reflectively analyze performance to improve expressive communication. PMID:25400601
Aerocapture Performance Analysis for a Neptune-Triton Exploration Mission
NASA Technical Reports Server (NTRS)
Starr, Brett R.; Westhelle, Carlos H.; Masciarelli, James P.
2004-01-01
A systems analysis has been conducted for a Neptune-Triton Exploration Mission in which aerocapture is used to capture a spacecraft at Neptune. Aerocapture uses aerodynamic drag instead of propulsion to decelerate from the interplanetary approach trajectory to a captured orbit during a single pass through the atmosphere. After capture, propulsion is used to move the spacecraft from the initial captured orbit to the desired science orbit. A preliminary assessment identified that a spacecraft with a lift to drag ratio of 0.8 was required for aerocapture. Performance analyses of the 0.8 L/D vehicle were performed using a high fidelity flight simulation within a Monte Carlo executive to determine mission success statistics. The simulation was the Program to Optimize Simulated Trajectories (POST) modified to include Neptune specific atmospheric and planet models, spacecraft aerodynamic characteristics, and interplanetary trajectory models. To these were added autonomous guidance and pseudo flight controller models. The Monte Carlo analyses incorporated approach trajectory delivery errors, aerodynamic characteristics uncertainties, and atmospheric density variations. Monte Carlo analyses were performed for a reference set of uncertainties and sets of uncertainties modified to produce increased and reduced atmospheric variability. For the reference uncertainties, the 0.8 L/D flatbottom ellipsled vehicle achieves 100% successful capture and has a 99.87 probability of attaining the science orbit with a 360 m/s V budget for apoapsis and periapsis adjustment. Monte Carlo analyses were also performed for a guidance system that modulates both bank angle and angle of attack with the reference set of uncertainties. An alpha and bank modulation guidance system reduces the 99.87 percentile DELTA V 173 m/s (48%) to 187 m/s for the reference set of uncertainties.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlsbad Field Office
The Performance Demonstration Program (PDP) for headspace gases distributes blind audit samples in a gas matrix for analysis of volatile organic compounds (VOCs). Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardousmore » Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility’s compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document. Participating measurement facilities must analyze PDP samples using the same procedures used for routine waste characterization analyses of WIPP samples.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlsbad Field Office
The Performance Demonstration Program (PDP) for headspace gases distributes sample gases of volatile organic compounds (VOCs) for analysis. Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issuedmore » by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility’s compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document. Participating measurement facilities must analyze PDP samples using the same procedures used for routine waste characterization analyses of WIPP samples.« less
Lu, Sara A; Wickens, Christopher D; Prinet, Julie C; Hutchins, Shaun D; Sarter, Nadine; Sebok, Angelia
2013-08-01
The aim of this study was to integrate empirical data showing the effects of interrupting task modality on the performance of an ongoing visual-manual task and the interrupting task itself. The goal is to support interruption management and the design of multimodal interfaces. Multimodal interfaces have been proposed as a promising means to support interruption management.To ensure the effectiveness of this approach, their design needs to be based on an analysis of empirical data concerning the effectiveness of individual and redundant channels of information presentation. Three meta-analyses were conducted to contrast performance on an ongoing visual task and interrupting tasks as a function of interrupting task modality (auditory vs. tactile, auditory vs. visual, and single modality vs. redundant auditory-visual). In total, 68 studies were included and six moderator variables were considered. The main findings from the meta-analyses are that response times are faster for tactile interrupting tasks in case of low-urgency messages.Accuracy is higher with tactile interrupting tasks for low-complexity signals but higher with auditory interrupting tasks for high-complexity signals. Redundant auditory-visual combinations are preferable for communication tasks during high workload and with a small visual angle of separation. The three meta-analyses contribute to the knowledge base in multimodal information processing and design. They highlight the importance of moderator variables in predicting the effects of interruption task modality on ongoing and interrupting task performance. The findings from this research will help inform the design of multimodal interfaces in data-rich, event-driven domains.
Pericardial Fat is Associated With Atrial Conduction: The Framingham Heart Study
Friedman, Daniel J.; Wang, Na; Meigs, James B.; Hoffmann, Udo; Massaro, Joseph M.; Fox, Caroline S.; Magnani, Jared W.
2014-01-01
Background Obesity is associated with altered atrial electrophysiology and a prominent risk factor for atrial fibrillation. Body mass index, the most widely used adiposity measure, has been related to atrial electrical remodeling. We tested the hypothesis that pericardial fat is independently associated with electrocardiographic measures of atrial conduction. Methods and Results We performed a cross‐sectional analysis of 1946 Framingham Heart Study participants (45% women) to determine the relation between pericardial fat and atrial conduction as measured by P wave indices (PWI): PR interval, P wave duration (P‐duration), P wave amplitude (P‐amplitude), P wave area (P‐area), and P wave terminal force (P‐terminal). We performed sex‐stratified linear regression analyses adjusted for relevant clinical variables and ectopic fat depots. Each 1‐SD increase in pericardial fat was significantly associated with PR interval (β=1.7 ms, P=0.049), P‐duration (β=2.3 ms, P<0.001), and P‐terminal (β=297 μV·ms, P<0.001) among women; and P‐duration (β=1.2 ms, P=0.002), P‐amplitude (β=−2.5 μV, P<0. 001), and P‐terminal (β=160 μV·ms, P=0.002) among men. Among both sexes, pericardial fat was significantly associated with P‐duration in analyses additionally adjusting for visceral fat or intrathoracic fat; a similar but non‐significant trend existed with P‐terminal. Among women, pericardial fat was significantly associated with P wave area after adjustment for visceral and intrathoracic fat. Conclusions Pericardial fat is associated with atrial conduction as quantified by PWI, even with adjustment for extracardiac fat depots. Further studies are warranted to identify the mechanisms through which pericardial fat may modify atrial electrophysiology and promote subsequent risk for arrhythmogenesis. PMID:24595189
OMEGA: A NEW COLD X-RAY SIMULATION FACILITY FOR THE EVALUATION OF OPTICAL COATINGS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fisher, J H; Newlander, C D; Fournier, K B
We report on recent progress for the development of a new cold X-ray optical test capability using the Omega Facility located at the Laboratory for Laser Energetics (LLE) at the University of Rochester. These tests were done on the 30 kJ OMEGA laser at the Laboratory for Laser Energetics (LLE) at the University of Rochester, Rochester, NY. We conducted a six-shot series called OMEGA II on 14 July 2006 in one eight-hour day (supported by the Defense Threat Reduction Agency). The initial testing was performed using simple protected gold optical coatings on fused silica substrates. PUFFTFT analyses were completed andmore » the specimen's thermal lateral stress and transverse stress conditions were calculated and interpreted. No major anomalies were detected. Comparison of the pre- and posttest reflective measurements coupled with the TFCALC analyses proved invaluable in guiding the analyses and interpreting the observed damage. The Omega facility is a high quality facility for performing evaluation of optical coatings and coupons and provides experience for the development of future National Ignition Facility (NIF) testing.« less
Analyzing Big Data in Psychology: A Split/Analyze/Meta-Analyze Approach
Cheung, Mike W.-L.; Jak, Suzanne
2016-01-01
Big data is a field that has traditionally been dominated by disciplines such as computer science and business, where mainly data-driven analyses have been performed. Psychology, a discipline in which a strong emphasis is placed on behavioral theories and empirical research, has the potential to contribute greatly to the big data movement. However, one challenge to psychologists—and probably the most crucial one—is that most researchers may not have the necessary programming and computational skills to analyze big data. In this study we argue that psychologists can also conduct big data research and that, rather than trying to acquire new programming and computational skills, they should focus on their strengths, such as performing psychometric analyses and testing theories using multivariate analyses to explain phenomena. We propose a split/analyze/meta-analyze approach that allows psychologists to easily analyze big data. Two real datasets are used to demonstrate the proposed procedures in R. A new research agenda related to the analysis of big data in psychology is outlined at the end of the study. PMID:27242639
Analyzing Big Data in Psychology: A Split/Analyze/Meta-Analyze Approach.
Cheung, Mike W-L; Jak, Suzanne
2016-01-01
Big data is a field that has traditionally been dominated by disciplines such as computer science and business, where mainly data-driven analyses have been performed. Psychology, a discipline in which a strong emphasis is placed on behavioral theories and empirical research, has the potential to contribute greatly to the big data movement. However, one challenge to psychologists-and probably the most crucial one-is that most researchers may not have the necessary programming and computational skills to analyze big data. In this study we argue that psychologists can also conduct big data research and that, rather than trying to acquire new programming and computational skills, they should focus on their strengths, such as performing psychometric analyses and testing theories using multivariate analyses to explain phenomena. We propose a split/analyze/meta-analyze approach that allows psychologists to easily analyze big data. Two real datasets are used to demonstrate the proposed procedures in R. A new research agenda related to the analysis of big data in psychology is outlined at the end of the study.
BASIC Programming In Water And Wastewater Analysis
NASA Technical Reports Server (NTRS)
Dreschel, Thomas
1988-01-01
Collection of computer programs assembled for use in water-analysis laboratories. First program calculates quality-control parameters used in routine water analysis. Second calculates line of best fit for standard concentrations and absorbances entered. Third calculates specific conductance from conductivity measurement and temperature at which measurement taken. Fourth calculates any one of four types of residue measured in water. Fifth, sixth, and seventh calculate results of titrations commonly performed on water samples. Eighth converts measurements, to actual dissolved-oxygen concentration using oxygen-saturation values for fresh and salt water. Ninth and tenth perform calculations of two other common titrimetric analyses. Eleventh calculates oil and grease residue from water sample. Last two use spectro-photometric measurements of absorbance at different wavelengths and residue measurements. Programs included in collection written for Hewlett-Packard 2647F in H-P BASIC.
Moretti, Laura; Di Mascio, Paola; Bellagamba, Simona
2017-06-16
The attention to sustainability-related issues has grown fast in recent decades. The experience gained with these themes reveals the importance of considering this topic in the construction industry, which represents an important sector throughout the world. This work consists on conducting a multicriteria analysis of four cement powders, with the objective of calculating and analysing the environmental, human health and socio-economic effects of their production processes. The economic, technical, environmental and safety performances of the examined powders result from official, both internal and public, documents prepared by the producers. The Analytic Hierarchy Process permitted to consider several indicators (i.e., environmental, human health related and socio-economic parameters) and to conduct comprehensive and unbiased analyses which gave the best, most sustainable cement powder. As assumed in this study, the contribution of each considered parameter to the overall sustainability has a different incidence, therefore the procedure could be used to support on-going sustainability efforts under different conditions. The results also prove that it is not appropriate to regard only one parameter to identify the 'best' cement powder, but several impact categories should be considered and analysed if there is an interest for pursuing different, often conflicting interests.
Powell, Sarah R.; Fuchs, Lynn S.
2014-01-01
According to national mathematics standards, algebra instruction should begin at kindergarten and continue through elementary school. Most often, teachers address algebra in the elementary grades with problems related to solving equations or understanding functions. With 789 2nd- grade students, we administered (a) measures of calculations and word problems in the fall and (b) an assessment of pre-algebraic reasoning, with items that assessed solving equations and functions, in the spring. Based on the calculation and word-problem measures, we placed 148 students into 1 of 4 difficulty status categories: typically performing, calculation difficulty, word-problem difficulty, or difficulty with calculations and word problems. Analyses of variance were conducted on the 148 students; path analytic mediation analyses were conducted on the larger sample of 789 students. Across analyses, results corroborated the finding that word-problem difficulty is more strongly associated with difficulty with pre-algebraic reasoning. As an indicator of later algebra difficulty, word-problem difficulty may be a more useful predictor than calculation difficulty, and students with word-problem difficulty may require a different level of algebraic reasoning intervention than students with calculation difficulty. PMID:25309044
Transportation systems analyses: Volume 1: Executive Summary
NASA Astrophysics Data System (ADS)
1993-05-01
The principal objective of this study is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform man delivery and return, cargo transfer, cargo delivery, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationships between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. This executive summary of the transportation systems analyses (TSM) semi-annual report addresses the SSF logistics resupply. Our analysis parallels the ongoing NASA SSF redesign effort. Therefore, there could be no SSF design to drive our logistics analysis. Consequently, the analysis attempted to bound the reasonable SSF design possibilities (and the subsequent transportation implications). No other strategy really exists until after a final decision is rendered on the SSF configuration.
Does Question Structure Affect Exam Performance in the Geosciences?
NASA Astrophysics Data System (ADS)
Day, E. A.; D'Arcy, M. K.; Craig, L.; Streule, M. J.; Passmore, E.; Irving, J. C. E.
2015-12-01
The jump to university level exams can be challenging for some students, often resulting in poor marks, which may be detrimental to their confidence and ultimately affect their overall degree class. Previous studies have found that question structure can have a strong impact on the performance of students in college level exams (see Gibson et al., 2015, for a discussion of its impact on physics undergraduates). Here, we investigate the effect of question structure on the exam results of geology and geophysics undergraduate students. Specifically, we analyse the performance of students in questions that have a 'scaffolded' framework and compare them to their performance in open-ended questions and coursework. We also investigate if observed differences in exam performance are correlated with the educational background and gender of students, amongst other factors. It is important for all students to be able to access their degree courses, no matter what their backgrounds may be. Broadening participation in the geosciences relies on removing systematic barriers to achievement. Therefore we recommend that exams are either structured with scaffolding in questions at lower levels, or students are explicitly prepared for this transition. We also recommend that longitudinal studies of exam performance are conducted within individual departments, and this work outlines one approach to analysing performance data.
Evaluation of MPLM Design and Mission 6A Coupled Loads Analyses
NASA Technical Reports Server (NTRS)
Bookout, Paul S.; Ricks, Ed
1999-01-01
Through the development of a space shuttle payload, there are usually several coupled loads analyses (CLA) performed: preliminary design, critical design, final design and verification loads analysis (VLA). A final design CLA is the last analysis conducted prior to model delivery to the shuttle program for the VLA. The finite element models used in the final design CLA and the VLA are test verified dynamic math models. Mission 6A is the first of many flights of the Multi-Purpose Logistics Module (MPLM). The MPLM was developed by Alenia Spazio S.p.A. (an Italian aerospace company) and houses the International Standard Payload Racks (ISPR) for transportation to the space station in the shuttle. Marshall Space Flight Center (MSFC), the payload integrator of the MPLM for Mission 6A, performed the final design CLA using the M6.OZC shuttle data for liftoff and landing conditions using the proper shuttle cargo manifest. Alenia performed the preliminary and critical design CLAs for the development of the MPLM. However, these CLAs did not use the current Mission 6A cargo manifest. An evaluation of the preliminary and critical design performed by Alenia and the final design performed by MSFC is presented.
Probability of Failure Analysis Standards and Guidelines for Expendable Launch Vehicles
NASA Astrophysics Data System (ADS)
Wilde, Paul D.; Morse, Elisabeth L.; Rosati, Paul; Cather, Corey
2013-09-01
Recognizing the central importance of probability of failure estimates to ensuring public safety for launches, the Federal Aviation Administration (FAA), Office of Commercial Space Transportation (AST), the National Aeronautics and Space Administration (NASA), and U.S. Air Force (USAF), through the Common Standards Working Group (CSWG), developed a guide for conducting valid probability of failure (POF) analyses for expendable launch vehicles (ELV), with an emphasis on POF analysis for new ELVs. A probability of failure analysis for an ELV produces estimates of the likelihood of occurrence of potentially hazardous events, which are critical inputs to launch risk analysis of debris, toxic, or explosive hazards. This guide is intended to document a framework for POF analyses commonly accepted in the US, and should be useful to anyone who performs or evaluates launch risk analyses for new ELVs. The CSWG guidelines provide performance standards and definitions of key terms, and are being revised to address allocation to flight times and vehicle response modes. The POF performance standard allows a launch operator to employ alternative, potentially innovative methodologies so long as the results satisfy the performance standard. Current POF analysis practice at US ranges includes multiple methodologies described in the guidelines as accepted methods, but not necessarily the only methods available to demonstrate compliance with the performance standard. The guidelines include illustrative examples for each POF analysis method, which are intended to illustrate an acceptable level of fidelity for ELV POF analyses used to ensure public safety. The focus is on providing guiding principles rather than "recipe lists." Independent reviews of these guidelines were performed to assess their logic, completeness, accuracy, self- consistency, consistency with risk analysis practices, use of available information, and ease of applicability. The independent reviews confirmed the general validity of the performance standard approach and suggested potential updates to improve the accuracy each of the example methods, especially to address reliability growth.
Gudlaugsdottir, Katrin; Andrews, James
2017-01-01
Objective Our objective was to evaluate quality of conduct and reporting of published systematic reviews and meta-analyses in paediatric surgery. We also aimed to identify characteristics predictive of review quality. Background Systematic reviews summarise evidence by combining sources, but are potentially prone to bias. To counter this, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was published to aid in reporting. Similarly, the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) measurement tool was designed to appraise methodology. The paediatric surgical literature has seen an increasing number of reviews over the past decade, but quality has not been evaluated. Methods Adhering to PRISMA guidelines, we performed a systematic review with a priori design to identify systematic reviews and meta-analyses of interventions in paediatric surgery. From 01/2010 to 06/2016, we searched: MEDLINE, EMBASE, Cochrane, Centre for Reviews and Dissemination, Web of Science, Google Scholar, reference lists and journals. Two reviewers independently selected studies and extracted data. We assessed conduct and reporting using AMSTAR and PRISMA. Scores were calculated as the sum of reported items. We also extracted author, journal and article characteristics, and used them in exploratory analysis to determine which variables predict quality. Results 112 articles fulfilled eligibility criteria (53 systematic reviews; 59 meta-analyses). Overall, 68% AMSTAR and 56.8% PRISMA items were reported adequately. Poorest scores were identified with regards a priori design, inclusion of structured summaries, including the grey literature, citing excluded articles and evaluating bias. 13 reviews were pre-registered and 6 in PRISMA-endorsing journals. The following predicted quality in univariate analysis:, word count, Cochrane review, journal h-index, impact factor, journal endorses PRISMA, PRISMA adherence suggested in author guidance, article mentions PRISMA, review includes comparison of interventions and review registration. The latter three variables were significant in multivariate regression. Conclusions There are gaps in the conduct and reporting of systematic reviews in paediatric surgery. More endorsement by journals of the PRISMA guideline may improve review quality, and the dissemination of reliable evidence to paediatric clinicians. PMID:28384296
Analysis and Verification of HET 1 m Mirror Deflections Due to Edge Sensor Loading
NASA Technical Reports Server (NTRS)
Stallcup, Michael A.; Whitaker, Ann F. (Technical Monitor)
2001-01-01
The ninety-one 1 m mirror segments which comprise the McDonald Observatory Hobby Eberly Telescope (HET) primary mirror have been observed to drift out of alignment in an unpredictable manner in response to time variant temperature deviations. A Segment Alignment Maintenance System (SAMS) is being developed to detect and correct this segment-to-segment drift using sensors mounted at the edges of the mirror segments. However, the segments were not originally designed to carry the weight of edge sensors. Thus, analyses and tests were conducted as part of the SAMS design to estimate the magnitude and shape of the edge sensor induced deformations as well as the resultant optical performance. Interferometric testing of a 26 m radius of curvature HET mirror segment was performed at the Marshall Space Flight Center using several load conditions to verify the finite element analyses.
Doping control analysis at the Rio 2016 Olympic and Paralympic Games.
Pereira, Henrique Marcelo Gualberto; Sardela, Vinicius Figueiredo; Padilha, Monica Costa; Mirotti, Luciana; Casilli, Alessandro; de Oliveira, Fabio Azamor; de Albuquerque Cavalcanti, Gustavo; Rodrigues, Lucas Martins Lisandro; de Araujo, Amanda Lessa Dutra; Levy, Rachel Santos; Teixeira, Pedro Antonio Castelo; de Oliveira, Felipe Alves Gomes; Duarte, Ana Carolina Giordani; Carneiro, Ana Carolina Dudenhoeffer; Evaristo, Joseph Albert Medeiros; Dos Santos, Gustavo Ramalho Cardoso; da Costa, Giovanni Carlo Verissimo; de Lima Castro, Fernando; Nogueira, Fabio Cesar Sousa; Scalco, Fernanda Bertão; Pizzatti, Luciana; de Aquino Neto, Francisco Radler
2017-11-01
This paper summarises the results obtained from the doping control analyses performed during the Summer XXXI Olympic Games (August 3-21, 2016) and the XV Paralympic Games (September 7-18, 2016). The analyses of all doping control samples were performed at the Brazilian Doping Control Laboratory (LBCD), a World Anti-Doping Agency (WADA)-accredited laboratory located in Rio de Janeiro, Brazil. A new facility at Rio de Janeiro Federal University (UFRJ) was built and fully operated by over 700 professionals, including Brazilian and international scientists, administrative staff, and volunteers. For the Olympic Games, 4913 samples were analysed. In 29 specimens, the presence of a prohibited substance was confirmed, resulting in adverse analytical findings (AAFs). For the Paralympic Games, 1687 samples were analysed, 12 of which were reported as AAFs. For both events, 82.8% of the samples were urine, and 17.2% were blood samples. In total, more than 31 000 analytical procedures were conducted. New WADA technical documents were fully implemented; consequently, state-of-the-art analytical toxicology instrumentation and strategies were applied during the Games, including different types of mass spectrometry (MS) analysers, peptide, and protein detection strategies, endogenous steroid profile measurements, and blood analysis. This enormous investment yielded one of the largest Olympic legacies in Brazil and South America. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Rognoni, Carla; Tarricone, Rosanna
2017-01-10
Intermittent catheterisation is the method of choice for the management of bladder dysfunctions. Different urinary catheters are available, but there is conflicting evidence on which type of catheter is best. The present study provides an objective evaluation of the clinical effectiveness of different subsets of urinary catheters. A systematic literature review was performed for published RCTs regarding hydrophilic coated and PVC (standard) catheters for intermittent catheterisation. Separate meta-analyses were conducted to combine data on frequencies of urinary tract infections (UTIs) and haematuria. Two separate analyses were performed, including or excluding reused standard catheters. Seven studies were eligible for inclusion in the review. The meta-analyses exploring UTI frequencies showed a lower risk ratio associated with hydrophilic catheters in comparison to standard ones (RR = 0.84; 95% CI, 0.75-0.94; p = 0.003). Results for the "reuse" scenario were consistent with the ones related to "single-use" scenario in terms of frequency of UTIs. The meta-analyses exploring haematuria were not able to demonstrate any statistically significant difference between hydrophilic catheters in comparison to standard ones. The findings confirm previously reported benefits of hydrophilic catheters but a broader evaluation that takes into account also patient preferences, compliance of therapy, quality of life and costs would be needed to assess the economic sustainability of these advanced devices.
NASA Technical Reports Server (NTRS)
Annett, Martin S.; Polanco, Michael A.
2010-01-01
A full-scale crash test of an MD-500 helicopter was conducted in December 2009 at NASA Langley's Landing and Impact Research facility (LandIR). The MD-500 helicopter was fitted with a composite honeycomb Deployable Energy Absorber (DEA) and tested under vertical and horizontal impact velocities of 26-ft/sec and 40-ft/sec, respectively. The objectives of the test were to evaluate the performance of the DEA concept under realistic crash conditions and to generate test data for validation of a system integrated finite element model. In preparation for the full-scale crash test, a series of sub-scale and MD-500 mass simulator tests was conducted to evaluate the impact performances of various components, including a new crush tube and the DEA blocks. Parameters defined within the system integrated finite element model were determined from these tests. The objective of this paper is to summarize the finite element models developed and analyses performed, beginning with pre-test predictions and continuing through post-test validation.
LS-DYNA Analysis of a Full-Scale Helicopter Crash Test
NASA Technical Reports Server (NTRS)
Annett, Martin S.
2010-01-01
A full-scale crash test of an MD-500 helicopter was conducted in December 2009 at NASA Langley's Landing and Impact Research facility (LandIR). The MD-500 helicopter was fitted with a composite honeycomb Deployable Energy Absorber (DEA) and tested under vertical and horizontal impact velocities of 26 ft/sec and 40 ft/sec, respectively. The objectives of the test were to evaluate the performance of the DEA concept under realistic crash conditions and to generate test data for validation of a system integrated LS-DYNA finite element model. In preparation for the full-scale crash test, a series of sub-scale and MD-500 mass simulator tests was conducted to evaluate the impact performances of various components, including a new crush tube and the DEA blocks. Parameters defined within the system integrated finite element model were determined from these tests. The objective of this paper is to summarize the finite element models developed and analyses performed, beginning with pre-test and continuing through post test validation.
Seismic performance for vertical geometric irregularity frame structures
NASA Astrophysics Data System (ADS)
Ismail, R.; Mahmud, N. A.; Ishak, I. S.
2018-04-01
This research highlights the result of vertical geometric irregularity frame structures. The aid of finite element analysis software, LUSAS was used to analyse seismic performance by focusing particularly on type of irregular frame on the differences in height floors and continued in the middle of the building. Malaysia’s building structures were affected once the earthquake took place in the neighbouring country such as Indonesia (Sumatera Island). In Malaysia, concrete is widely used in building construction and limited tension resistance to prevent it. Analysing structural behavior with horizontal and vertical static load is commonly analyses by using the Plane Frame Analysis. The case study of this research is to determine the stress and displacement in the seismic response under this type of irregular frame structures. This study is based on seven-storey building of Clinical Training Centre located in Sungai Buloh, Selayang, Selangor. Since the largest earthquake occurs in Acheh, Indonesia on December 26, 2004, the data was recorded and used in conducting this research. The result of stress and displacement using IMPlus seismic analysis in LUSAS Modeller Software under the seismic response of a formwork frame system states that the building is safe to withstand the ground and in good condition under the variation of seismic performance.
Thermal-Structural Analysis of PICA Tiles for Solar Tower Test
NASA Technical Reports Server (NTRS)
Agrawal, Parul; Empey, Daniel M.; Squire, Thomas H.
2009-01-01
Thermal protection materials used in spacecraft heatshields are subjected to severe thermal and mechanical loading environments during re-entry into earth atmosphere. In order to investigate the reliability of PICA tiles in the presence of high thermal gradients as well as mechanical loads, the authors designed and conducted solar-tower tests. This paper presents the design and analysis work for this tests series. Coupled non-linear thermal-mechanical finite element analyses was conducted to estimate in-depth temperature distribution and stress contours for various cases. The first set of analyses performed on isolated PICA tile showed that stresses generated during the tests were below the PICA allowable limit and should not lead to any catastrophic failure during the test. The tests results were consistent with analytical predictions. The temperature distribution and magnitude of the measured strains were also consistent with predicted values. The second test series is designed to test the arrayed PICA tiles with various gap-filler materials. A nonlinear contact method is used to model the complex geometry with various tiles. The analyses for these coupons predict the stress contours in PICA and inside gap fillers. Suitable mechanical loads for this architecture will be predicted, which can be applied during the test to exceed the allowable limits and demonstrate failure modes. Thermocouple and strain-gauge data obtained from the solar tower tests will be used for subsequent analyses and validation of FEM models.
Features of Computer-Based Decision Aids: Systematic Review, Thematic Synthesis, and Meta-Analyses.
Syrowatka, Ania; Krömker, Dörthe; Meguerditchian, Ari N; Tamblyn, Robyn
2016-01-26
Patient information and education, such as decision aids, are gradually moving toward online, computer-based environments. Considerable research has been conducted to guide content and presentation of decision aids. However, given the relatively new shift to computer-based support, little attention has been given to how multimedia and interactivity can improve upon paper-based decision aids. The first objective of this review was to summarize published literature into a proposed classification of features that have been integrated into computer-based decision aids. Building on this classification, the second objective was to assess whether integration of specific features was associated with higher-quality decision making. Relevant studies were located by searching MEDLINE, Embase, CINAHL, and CENTRAL databases. The review identified studies that evaluated computer-based decision aids for adults faced with preference-sensitive medical decisions and reported quality of decision-making outcomes. A thematic synthesis was conducted to develop the classification of features. Subsequently, meta-analyses were conducted based on standardized mean differences (SMD) from randomized controlled trials (RCTs) that reported knowledge or decisional conflict. Further subgroup analyses compared pooled SMDs for decision aids that incorporated a specific feature to other computer-based decision aids that did not incorporate the feature, to assess whether specific features improved quality of decision making. Of 3541 unique publications, 58 studies met the target criteria and were included in the thematic synthesis. The synthesis identified six features: content control, tailoring, patient narratives, explicit values clarification, feedback, and social support. A subset of 26 RCTs from the thematic synthesis was used to conduct the meta-analyses. As expected, computer-based decision aids performed better than usual care or alternative aids; however, some features performed better than others. Integration of content control improved quality of decision making (SMD 0.59 vs 0.23 for knowledge; SMD 0.39 vs 0.29 for decisional conflict). In contrast, tailoring reduced quality of decision making (SMD 0.40 vs 0.71 for knowledge; SMD 0.25 vs 0.52 for decisional conflict). Similarly, patient narratives also reduced quality of decision making (SMD 0.43 vs 0.65 for knowledge; SMD 0.17 vs 0.46 for decisional conflict). Results were varied for different types of explicit values clarification, feedback, and social support. Integration of media rich or interactive features into computer-based decision aids can improve quality of preference-sensitive decision making. However, this is an emerging field with limited evidence to guide use. The systematic review and thematic synthesis identified features that have been integrated into available computer-based decision aids, in an effort to facilitate reporting of these features and to promote integration of such features into decision aids. The meta-analyses and associated subgroup analyses provide preliminary evidence to support integration of specific features into future decision aids. Further research can focus on clarifying independent contributions of specific features through experimental designs and refining the designs of features to improve effectiveness.
NASA Technical Reports Server (NTRS)
Taylor, W. W. L.
1979-01-01
Shuttle charging is discussed and two analyses of shuttle charging are performed. The first predicts the effective collecting area of a wire grid, biased with the respect to the potential of the magnetoplasma surrounding it. The second predicts the intensity of broadband electromagnetic noise that is emitted when surface electrostatic discharges occur between the beta cloth and the wire grid sewn on it.
NASA Astrophysics Data System (ADS)
Blanco, J.; Salas, Y.; Jiménez, C.; Pineda, Y.; Bustamante, A.
2017-12-01
In some Engineering fields, we need that conductive materials have a mechanic performance and specific electrical for that they maintain conditions or corrosive attack if they are in the environment or if they are closed structure. The stainless steels have an inert film on their surface and it has the function to act in contrast to external agents who generates the corrosion, especially for stings, spoiling the film until to fail. We found a solution taking into account the electrical performance and the anticorrosive; into the process we put recovering of specific oxides on, stainless steel using the method of sputtering with Unbalanced Magnetron, (UBM) varying the oxygen in the reactive environment. The coating obtained had a thickness one micron approximately and we saw on serious structural uniformity [1]. The corrosion resistance was evaluated through the potentiodynamics polarization and electrochemical spectroscopy impedance in NACL according to the standard. The cathode protection is the most important method employed for the corrosion prevention of metallic structures in the soil or immersed on the water. The electrical resistivity was evaluated with the four points methods and it showed a behaviour of diode type in some substrates with a threshold potential in several volts. We noticed a simple resistance solution when it was analysed in the Nyquist graphics whit the Electrochemical Impedance Spectroscopy technique. With on equivalent circuit, for this reason we determinate a variation in the corrosion speed in almost two orders of magnitude when we analysed the potentiodynamics curve by Tafel approximation. The data obtained and analysed show that this type of surface modification maintains the conductivity condition at the interface, improving the resistance in relation whit the corrosion of these elements where the recovering allowed the ionic flow wished for overcoming threshold voltage, acting as an insulator in different cases.
Productivity of public hospitals in Nepal: a data envelopment analysis.
Silwal, Pushkar Raj; Ashton, Toni
2017-07-20
Public hospitals in Nepal account for a major share of the total health budget. Therefore, questions are often asked about the performance of these hospitals. Existing measures of performance are limited to historical ratio analyses without any benchmarks. The objective of this study is to explore the trends in inputs, outputs and productivity changes in Nepalese public hospitals from 2011-2012 to 2013-2014. The study was conducted among 32 Nepalese public hospitals (23 district level and 9 higher level) for the three fiscal years from 2011-2012 to 2013-2014. First, basic ratio analyses were conducted for the input and output measures over the study years. Then, Malmquist productivity change scores were obtained using data envelopment analysis. Aggregated as well as separate analyses were conducted for district level and higher level hospitals. Real expenditures of the sampled hospitals declined over the 3-year period from an average of US$ 371 000 in year 1 to US$ 368 730 in year 2 and US$ 328680 in year 3. The average aggregated hospital outputs increased marginally from 8276 in 2011-2012 to 8613 in 2013-2014. The total factor productivity of the study hospitals declined by 6.9% annually from 2011-2012 to 2013-2014. Of the total 32 hospitals, productivity increased in only 12 (37.5%) hospitals and declined in the remaining 20 hospitals. The total factor productivity loss was influenced by a decline in technology change, despite an increase in efficiency. In general, productivity of the study hospitals declined over the study period. Availability and accessibility of accurate, detailed and consistent measures of hospital inputs and outputs is a major challenge for this type of analysis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Koster, Geert; Bekema, Hanneke J; Wetterslev, Jørn; Gluud, Christian; Keus, Frederik; van der Horst, Iwan C C
2016-09-01
Milrinone is an inotrope widely used for treatment of cardiac failure. Because previous meta-analyses had methodological flaws, we decided to conduct a systematic review of the effect of milrinone in critically ill adult patients with cardiac dysfunction. This systematic review was performed according to The Cochrane Handbook for Systematic Reviews of Interventions. Searches were conducted until November 2015. Patients with cardiac dysfunction were included. The primary outcome was serious adverse events (SAE) including mortality at maximum follow-up. The risk of bias was evaluated and trial sequential analyses were conducted. The quality of evidence was assessed by the Grading of Recommendations Assessment, Development and Evaluation criteria. A total of 31 randomised clinical trials fulfilled the inclusion criteria, of which 16 provided data for our analyses. All trials were at high risk of bias, and none reported the primary composite outcome SAE. Fourteen trials with 1611 randomised patients reported mortality data at maximum follow-up (RR 0.96; 95% confidence interval 0.76-1.21). Milrinone did not significantly affect other patient-centred outcomes. All analyses displayed statistical and/or clinical heterogeneity of patients, interventions, comparators, outcomes, and/or settings and all featured missing data. The current evidence on the use of milrinone in critically ill adult patients with cardiac dysfunction suffers from considerable risks of both bias and random error and demonstrates no benefits. The use of milrinone for the treatment of critically ill patients with cardiac dysfunction can be neither recommended nor refuted. Future randomised clinical trials need to be sufficiently large and designed to have low risk of bias.
Grosso, Giuseppe; Micek, Agnieszka; Godos, Justyna; Pajak, Andrzej; Sciacca, Salvatore; Bes-Rastrollo, Maira; Galvano, Fabio; Martinez-Gonzalez, Miguel A
2017-08-17
To perform a dose-response meta-analysis of prospective cohort studies investigating the association between long-term coffee intake and risk of hypertension. An online systematic search of studies published up to November 2016 was performed. Linear and non-linear dose-response meta-analyses were conducted; potential evidence of heterogeneity, publication bias, and confounding effect of selected variables were investigated through sensitivity and meta-regression analyses. Seven cohorts including 205,349 individuals and 44,120 cases of hypertension were included. In the non-linear analysis, there was a 9% significant decreased risk of hypertension per seven cups of coffee a day, while, in the linear dose-response association, there was a 1% decreased risk of hypertension for each additional cup of coffee per day. Among subgroups, there were significant inverse associations for females, caffeinated coffee, and studies conducted in the US with longer follow-up. Analysis of potential confounders revealed that smoking-related variables weakened the strength of association between coffee consumption and risk of hypertension. Increased coffee consumption is associated with a modest decrease in risk of hypertension in prospective cohort studies. Smoking status is a potential effect modifier on the association between coffee consumption and risk of hypertension.
Teis, Rachel; Allen, Jyai; Lee, Nigel; Kildea, Sue
2017-02-01
No study has tested a Crisis Resource Management prompt on resuscitation performance. We conducted a feasibility, unblinded, parallel-group, randomised controlled trial at one Australian paediatric hospital (June-September 2014). Eligible participants were any doctor, nurse, or nurse manager who would normally be involved in a Medical Emergency Team simulation. The unit of block randomisation was one of six scenarios (3 control:3 intervention) with or without a verbal prompt. The primary outcomes tested the feasibility and utility of the intervention and data collection tools. The secondary outcomes measured resuscitation quality and team performance. Data were analysed from six resuscitation scenarios (n=49 participants); three control groups (n=25) and three intervention groups (n=24). The ability to measure all data items on the data collection tools was hindered by problems with the recording devices both in the mannequins and the video camera. For a pilot study, greater training for the prompt role and pre-briefing participants about assessment of their cardio-pulmonary resuscitation quality should be undertaken. Data could be analysed in real time with independent video analysis to validate findings. Two cameras would strengthen reliability of the methods. Copyright © 2016 College of Emergency Nursing Australasia. Published by Elsevier Ltd. All rights reserved.
Contamination of commercial cane sugars by some organic acids and some inorganic anions.
Wojtczak, Maciej; Antczak, Aneta; Lisik, Krystyna
2013-01-01
The aim of the paper was the identification and the quantitative evaluation of the following inorganic anions: chloride, phosphate, nitrate, nitrite, sulphate and the following organic acids: lactic, acetic, formic, malic and citric in commercial "unrefined" brown cane sugars and in cane raw sugars. The determination was carried out by high performance anion exchange chromatography with conductivity detector HPAEC-CD. The conducted analyses have shown that the content of some inorganic anions and organic acids in cane sugars may be an important criterion of the quality of commercial "unrefined" brown cane sugars. Copyright © 2012 Elsevier Ltd. All rights reserved.
Chemical Analysis and Water Recovery Testing of Shuttle-Mir Humidity Condensate
NASA Technical Reports Server (NTRS)
Mudgett, Paul D.; Straub, John E., II; Schultz, John R.; Sauer, Richard L.; Williams, David E.; Bobe, L. S.; Novikov, V. M.; Andreichouk, P. O.; Protasov, N. N.
1999-01-01
Humidity condensate collected and processed in-flight is an important component of a space station drinking water supply. Water recovery systems in general are designed to handle finite concentrations of specific chemical components. Previous analyses of condensate derived from spacecraft and ground sources showed considerable variation in composition. Consequently, an investigation was conducted to collect condensate on the Shuttle while the vehicle was docked to Mir, and return the condensate to Earth for testing. This scenario emulates an early ISS configuration during a Shuttle docking, because the atmospheres intermix during docking and the condensate composition should reflect that. During the STS-89 and STS-91 flights, a total volume of 50 liters of condensate was collected and returned. Inorganic and organic chemical analyses were performed on aliquots of the fluid. Tests using the actual condensate were then conducted with scaled-down elements of the Russian condensate recovery system to determine the quality of water produced. The composition and test results are described, and implications for ISS are discussed.
Qiu, Xing; Hu, Rui; Wu, Zhixin
2014-01-01
Normalization procedures are widely used in high-throughput genomic data analyses to remove various technological noise and variations. They are known to have profound impact to the subsequent gene differential expression analysis. Although there has been some research in evaluating different normalization procedures, few attempts have been made to systematically evaluate the gene detection performances of normalization procedures from the bias-variance trade-off point of view, especially with strong gene differentiation effects and large sample size. In this paper, we conduct a thorough study to evaluate the effects of normalization procedures combined with several commonly used statistical tests and MTPs under different configurations of effect size and sample size. We conduct theoretical evaluation based on a random effect model, as well as simulation and biological data analyses to verify the results. Based on our findings, we provide some practical guidance for selecting a suitable normalization procedure under different scenarios. PMID:24941114
Murphy, Jennifer C.; Farmer, James; Layton, Alice
2016-06-13
The U.S. Geological Survey, in cooperation with the Tennessee Duck River Development Agency, monitored water quality at several locations in the upper Duck River watershed between October 2007 and September 2010. Discrete water samples collected at 24 sites in the watershed were analyzed for water quality, and Escherichia coli (E. coli) and enterococci concentrations. Additional analyses, including the determination of anthropogenic-organic compounds, bacterial concentration of resuspended sediment, and bacterial-source tracking, were performed at a subset of sites. Continuous monitoring of streamflow, turbidity, and specific conductance was conducted at seven sites; a subset of sites also was monitored for water temperature and dissolved oxygen concentration. Multiple-regression models were developed to predict instantaneous E. coli concentrations and loads at sites with continuous monitoring. This data collection effort, along with the E. coli models and predictions, support analyses of the relations among land use, bacteria source and transport, and basin hydrology in the upper Duck River watershed.
FEM investigation of concrete silos damaged and reinforced externally with CFRP
NASA Astrophysics Data System (ADS)
Kermiche, Sihem; Boussaid, Ouzine; Redjel, Bachir; Amirat, Abdelaziz
2018-03-01
The present work investigates the reinforcement of concrete wheat-grain silos under initial damage. The reinforcement is achieved by mounting bands of carbon fiber reinforced polymer (CFRP) on the external walls of the silo. 4 modes of reinforcement are adapted according to the width of the band, the gap between two bands, the height of reinforcement and the number of layers achieved through banding. Analytical analyses were conducted using the Reimbert method and the Eurocode 1 Part 4 method, as well as numerically through the finite element software Abaqus. Results show that the normal pressure reaches a peak value when approaching the silo hopper. Initial damage in a concrete silo was first determined using a 3D geometrical model, while the damage analyses were conducted to optimize the CFRP reinforcement by mounting 2 CFRP bands close together above and below the cylinder-hopper joint. Increasing the number of banding layers could produce better performance as the damage was slightly decreased from 0.161 to 0.152 for 1 and 4 layers respectively.
A Systematic Review of the Cost-Effectiveness of Biologics for Ulcerative Colitis.
Stawowczyk, Ewa; Kawalec, Paweł
2018-04-01
Ulcerative colitis (UC) is a chronic autoimmune inflammation of the colon. The condition significantly decreases quality of life and generates a substantial economic burden for healthcare payers, patients and the society in which they live. Some patients require chronic pharmacotherapy, and access to novel biologic drugs might be crucial for long-term remission. The analyses of cost-effectiveness for biologic drugs are necessary to assess their efficiency and provide the best available drugs to patients. Our aim was to collect and assess the quality of economic analyses carried out for biologic agents used in the treatment of UC, as well as to summarize evidence on the drivers of cost-effectiveness and evaluate the transferability and generalizability of conclusions. A systematic database review was conducted using MEDLINE (via PubMed), EMBASE, Cost-Effectiveness Analysis Registry and CRD0. Both authors independently reviewed the identified articles to determine their eligibility for final review. Hand searching of references in collected papers was also performed to find any relevant articles. The reporting quality of economic analyses included was evaluated by two reviewers using the International Society of Pharmacoeconomics and Outcomes Research (ISPOR) Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement checklist. We reviewed the sensitivity analyses in cost-effectiveness analyses to identify the variables that may have changed the conclusions of the study. Key drivers of cost-effectiveness were selected by identifying uncertain parameters that caused the highest change of the results of the analyses compared with base-case results. Of the 576 identified records, 87 were excluded as duplicates and 16 studies were included in the final review; evaluations for Canada, the UK and Poland were mostly performed. The majority of the evaluations revealed were performed for infliximab (approximately 75% of total volume); however, some assessments were also performed for adalimumab (50%) and golimumab (31%). Only three analyses were conducted for vedolizumab, whereas no relevant studies were found for etrolizumab and tofacitinib. The reporting quality of the included economic analyses was assessed as high, with an average score of 21 points per 24 maximum possible (range 14-23 points according to the ISPOR CHEERS statement checklist). In the case of most analyses, quality-adjusted life-years were used as a clinical outcome, and endpoints such as remission, response and mucosal healing were less common. The higher clinical effectiveness (based on response rates) of biological treatment over non-biological treatments was presented in revealed analyses. The incremental cost-utility ratios for biologics, compared with standard care, varied significantly between the studies and ranged from US$36,309 to US$456,979. The lowest value was obtained for infliximab and the highest for the treatment scheme including infliximab 5 mg/kg and infliximab 10 mg/kg + adalimumab. The change of utility weights and clinical parameters had the most significant influence on the results of the analysis; the variable related to surgery was the least sensitive. Limited data on the cost-effectiveness of UC therapy were identified. In the majority of studies, the lack of cost-effectiveness was revealed for biologics, which was associated with their high costs. Clinical outcomes are transferable to other countries and could be generalized; however, cost inputs are country-specific and therefore limit the transferability and generalizability of conclusions. The key drivers and variables that showed the greatest effect on the analysis results were utility weights and clinical parameters.
Tanaka, Haruka; Ogata, Soshiro; Omura, Kayoko; Honda, Chika; Kamide, Kei; Hayakawa, Kazuo
2016-03-01
The aim of this study was to investigate the association between subjective memory complaints (SMCs) and depressive symptoms, with and without adjustment for genetic and family environmental factors. We conducted a cross-sectional study using twins and measured SMCs and depressive symptoms as outcomes and explanatory variables, respectively. First, we performed regression analyses using generalized estimating equations to investigate the associations between SMCs and depressive symptoms without adjustment for genetic and family environmental factors (individual-level analyses). We then performed regression analyses for within-pair differences using monozygotic (MZ) and dizygotic (DZ) twin pairs and MZ twin pairs to investigate these associations with adjustment for genetic and family environmental factors by subtracting the values of one twin from those of co-twin variables (within-pair level analyses). Therefore, differences between the associations at individual- and within-pair level analyses suggested confounding by genetic factors. We included 556 twins aged ≥ 20 years. In the individual-level analyses, SMCs were significantly associated with depressive symptoms in both males and females [standardized coefficients: males, 0.23 (95% CI 0.08-0.38); females, 0.35 (95% CI 0.23-0.46)]. In the within-pair level analyses using MZ and same-sex DZ twin pairs, SMCs were significantly associated with depressive symptoms. In the within-pair level analyses using the MZ twin pairs, SMCs were significantly associated with depressive symptoms [standardized coefficients: males, 0.32 (95% CI 0.08-0.56); females, 0.24 (95% CI 0.13-0.42)]. This study suggested that SMCs were significantly associated with depressive symptoms after adjustment for genetic and family environmental factors.
NASA Technical Reports Server (NTRS)
Jeng, Frank F.
2007-01-01
Development of analysis guidelines for Exploration Life Support (ELS) technology tests was completed. The guidelines were developed based on analysis experiences gained from supporting Environmental Control and Life Support System (ECLSS) technology development in air revitalization systems and water recovery systems. Analyses are vital during all three phases of the ELS technology test: pre-test, during test and post test. Pre-test analyses of a test system help define hardware components, predict system and component performances, required test duration, sampling frequencies of operation parameters, etc. Analyses conducted during tests could verify the consistency of all the measurements and the performance of the test system. Post test analyses are an essential part of the test task. Results of post test analyses are an important factor in judging whether the technology development is a successful one. In addition, development of a rigorous model for a test system is an important objective of any new technology development. Test data analyses, especially post test data analyses, serve to verify the model. Test analyses have supported development of many ECLSS technologies. Some test analysis tasks in ECLSS technology development are listed in the Appendix. To have effective analysis support for ECLSS technology tests, analysis guidelines would be a useful tool. These test guidelines were developed based on experiences gained through previous analysis support of various ECLSS technology tests. A comment on analysis from an experienced NASA ECLSS manager (1) follows: "Bad analysis was one that bent the test to prove that the analysis was right to begin with. Good analysis was one that directed where the testing should go and also bridged the gap between the reality of the test facility and what was expected on orbit."
Complementary therapies for peripheral arterial disease: systematic review.
Pittler, Max H; Ernst, Edzard
2005-07-01
While peripheral arterial disease (PAD) affects a considerable proportion of patients in the primary care setting, there is a high level of use of complementary treatment options. The aim was to assess the effectiveness of any type of complementary therapy for peripheral arterial disease. A systematic review was performed. Literature searches were conducted on Medline, Embase, Amed, and the Cochrane Library until December 2004. Hand-searches of medical journals and bibliographies were conducted. There were no restrictions regarding the language of publication. The screening of studies, selection, data extraction, the assessment of methodologic quality and validation were performed independently by the two reviewers. Data from randomized controlled trials, and systematic reviews and meta-analyses, which based their findings on the results of randomized controlled trials were included. Seven systematic reviews and meta-analyses and three additional randomized controlled trials met the inclusion criteria and were reviewed. The evidence relates to acupuncture, biofeedback, chelation therapy, CO(2)-applications and the dietary supplements Allium sativum (garlic), Ginkgo biloba (ginkgo), omega-3 fatty acids, padma 28 and Vitamin E. Most studies included only patients with peripheral arterial disease in Fontaine stage II (intermittent claudication). The reviewed RCTs, systematic reviews and meta-analyses which based their findings on the results of RCTs suggest that G. biloba is effective compared with placebo for patients with intermittent claudication. Evidence also suggests that padma 28 is effective for intermittent claudication, although more data are required to confirm these findings. For all other complementary treatment options there is no evidence beyond reasonable doubt to suggest effectiveness for patients with peripheral arterial disease.
Xu, X-H; Xiong, D-H; Liu, X-G; Guo, Y; Chen, Y; Zhao, J; Recker, R R; Deng, H-W
2010-01-01
This study was conducted to test whether there exists an association between vitamin D-binding protein (DBP) gene and compression strength index (CSI) phenotype. Candidate gene association analyses were conducted in total sample, male subgroup, and female subgroup, respectively. Two single-nucleotide polymorphisms (SNPs) with significant association results were found in males, suggesting the importance of DBP gene polymorphisms on the variation in CSI especially in Caucasian males. CSI of the femoral neck (FN) is a newly developed phenotype integrating information about bone size, body size, and bone mineral density. It is considered to have the potential to improve the performance of risk assessment for hip fractures because it is based on a combination of phenotypic traits influencing hip fractures rather than a single trait. CSI is under moderate genetic determination (with a heritability of approximately 44% found in this study), but the relevant genetic study is still rather scarce. Based on the known physiological role of DBP in bone biology and the relatively high heritability of CSI, we tested 12 SNPs of the DBP gene for association with CSI variation in 405 Caucasian nuclear families comprising 1,873 subjects from the Midwestern US. Association analyses were performed in the total sample, male and female subgroups, respectively. Significant associations with CSI were found with two SNPs (rs222029, P = 0.0019; rs222020, P = 0.0042) for the male subgroup. Haplotype-based association tests corroborated the single-SNP results. Our findings suggest that the DBP gene might be one of the genetic factors influencing CSI phenotype in Caucasians, especially in males.
Escobar, Gabriel J; Baker, Jennifer M; Turk, Benjamin J; Draper, David; Liu, Vincent; Kipnis, Patricia
2017-01-01
Introduction This article is not a traditional research report. It describes how conducting a specific set of benchmarking analyses led us to broader reflections on hospital benchmarking. We reexamined an issue that has received far less attention from researchers than in the past: How variations in the hospital admission threshold might affect hospital rankings. Considering this threshold made us reconsider what benchmarking is and what future benchmarking studies might be like. Although we recognize that some of our assertions are speculative, they are based on our reading of the literature and previous and ongoing data analyses being conducted in our research unit. We describe the benchmarking analyses that led to these reflections. Objectives The Centers for Medicare and Medicaid Services’ Hospital Compare Web site includes data on fee-for-service Medicare beneficiaries but does not control for severity of illness, which requires physiologic data now available in most electronic medical records. To address this limitation, we compared hospital processes and outcomes among Kaiser Permanente Northern California’s (KPNC) Medicare Advantage beneficiaries and non-KPNC California Medicare beneficiaries between 2009 and 2010. Methods We assigned a simulated severity of illness measure to each record and explored the effect of having the additional information on outcomes. Results We found that if the admission severity of illness in non-KPNC hospitals increased, KPNC hospitals’ mortality performance would appear worse; conversely, if admission severity at non-KPNC hospitals’ decreased, KPNC hospitals’ performance would appear better. Conclusion Future hospital benchmarking should consider the impact of variation in admission thresholds. PMID:29035176
Key results of battery performance and life tests at Argonne National Laboratory
NASA Astrophysics Data System (ADS)
Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.
1991-12-01
Advanced battery technology evaluations are performed under simulated electric vehicle operating conditions at Argonne National Laboratory's & Diagnostic Laboratory (ADL). The ADL provide a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1991 on twelve single cells and eight 3- to 360-cell modules that encompass six battery technologies (Na/S, Li/MS, Ni/MH, Zn/Br, Ni/Fe, and Pb-Acid). These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division. The results measure progress in battery R & D programs, compare battery technologies, and provide basic data for modeling and continuing R & D to battery users, developers, and program managers.
Evaluation of risk factors for perforated peptic ulcer.
Yamamoto, Kazuki; Takahashi, Osamu; Arioka, Hiroko; Kobayashi, Daiki
2018-02-15
The aim of this study was to evaluate the prediction factors for perforated peptic ulcer (PPU). At St. Luke's International Hospital in Tokyo, Japan, a case control study was performed between August 2004 and March 2016. All patients diagnosed with PPU were included. As control subjects, patients with age, sex and date of CT scan corresponding to those of the PPU subjects were included in the study at a proportion of 2 controls for every PPU subject. All data such as past medical histories, physical findings, and laboratory data were collected through chart reviews. Univariate analyses and multivariate analyses with logistic regression were conducted, and receiver operating characteristic curves (ROCs) were calculated to show validity. Sensitivity analyses were performed to confirm results using a stepwise method and conditional logistic regression. A total of 408 patients were included in this study; 136 were a group of patients with PPU, and 272 were a control group. Univariate analysis showed statistical significance in many categories. Four different models of multivariate analyses were conducted, and significant differences were found for muscular defense and a history of peptic ulcer disease (PUD) in all models. The conditional forced-entry analysis of muscular defense showed an odds ratio (OR) of 23.8 (95% confidence interval [CI]: 5.70-100.0), and the analysis of PUD history showed an OR of 6.40 (95% CI: 1.13-36.2). The sensitivity analysis showed consistent results, with an OR of 23.8-366.2 for muscular defense and an OR of 3.67-7.81 for PUD history. The area under the curve (AUC) of all models was high enough to confirm the results. However, anticoagulants, known risk factors for PUD, did not increase the risk for PPU in our study. The conditional forced-entry analysis of anticoagulant use showed an OR of 0.85 (95% CI: 0.03-22.3). The evaluation of prediction factors and development of a prediction rule for PPU may help our decision making in performing a CT scan for patients with acute abdominal pain.
de Almeida Santana, Carla Caroliny; Farah, Breno Quintella; de Azevedo, Liane Beretta; Hill, James O; Gunnarsdottir, Thrudur; Botero, João Paulo; do Prado, Edna Cristina; do Prado, Wagner Luiz
2017-05-01
Obesity has been associated with poor academic achievement, while cardiorespiratory fitness (CRF) has been linked to academic success. To investigate whether CRF is associated with academic performance in Brazilian students, independently of body mass index (BMI), fatness and socioeconomic status (SES). 392 5th and 6th grade students (193 girls) (12.11 ± 0.75 years old) were evaluated in 2012. Skinfold thickness measures were performed, and students were classified according to BMI-percentile. CRF was estimated by a 20-meter shuttle run test, and academic achievement by standardized math and Portuguese tests. Multiple linear regression analyses were conducted to explore the association between academic performance and CRF, adjusted for SES, skinfold thickness or BMI-percentile. Among girls CRF was associated with higher academic achievement in math (β = 0.146;p = .003) and Portuguese (β = 0.129;p = .004) in crude and adjusted analyses. No significant association was found among boys. BMI was not associated with overall academic performance. There was a weak negative association between skinfold thickness and performance in mathematics in boys (β =- 0.030;p = .04), but not in girls. The results highlight the importance of maintaining high fitness levels in girls throughout adolescence a period commonly associated with reductions in physical activity levels and CRF.
Caffeine, cognitive failures and health in a non-working community sample.
Smith, Andrew P
2009-01-01
Most studies of the effects of caffeine on performance have been conducted in the laboratory and further information is required on the real-life effects of caffeine consumption on cognition. In addition, possible effects of caffeine consumption on a range of health outcomes should also be assessed in these studies to enable cost-benefit analyses to be conducted. Secondary analyses of a large epidemiological database (N = 3223 non-working participants, 57% female, with a mean age of 49.6 years, range 17-92 years) were conducted to examine associations between caffeine consumption (mean caffeine consumption was 140 mg/day, range 0-1800 mg) and cognitive failures (errors of memory, attention and action) in a non-working sample. Associations between caffeine consumption and physical and mental health problems were also examined. The study involved secondary analyses of a database formed by combining the Bristol Stress and Health at Work and Cardiff Health and Safety at Work studies. Associations between caffeine consumption and frequency of cognitive failures and health outcomes were examined in a sample of non-workers. After controlling for possible confounding factors significant associations between caffeine consumption and fewer cognitive failures were observed. Initial analyses suggested that many health variables were associated with regular level of caffeine consumption. However, most of the significant effects of caffeine disappeared when demographic and lifestyle factors were controlled for. Consumption of caffeine was, however, associated with a reduced risk of depression. These effects were also observed in separate analyses examining the source of the caffeine (coffee and tea). Overall, the results show that caffeine consumption may benefit cognitive functioning in a non-working population. This confirms earlier findings from working samples. This beneficial effect of caffeine was not associated with negative health consequences. Indeed, consumption of caffeine was found to be associated with a reduced risk of depression.
Alexander, Dominik D; Miller, Paige E; Van Elswyk, Mary E; Kuratko, Connye N; Bylsma, Lauren C
2017-01-01
To conduct meta-analyses of randomized controlled trials (RCTs) to estimate the effect of eicosapentaenoic and docosahexaenoic acid (EPA+DHA) on coronary heart disease (CHD), and to conduct meta-analyses of prospective cohort studies to estimate the association between EPA+DHA intake and CHD risk. A systematic literature search of Ovid/Medline, PubMed, Embase, and the Cochrane Library from January 1, 1947, to November 2, 2015, was conducted; 18 RCTs and 16 prospective cohort studies examining EPA+DHA from foods or supplements and CHD, including myocardial infarction, sudden cardiac death, coronary death, and angina, were identified. Random-effects meta-analysis models were used to generate summary relative risk estimates (SRREs) and 95% CIs. Heterogeneity was examined in subgroup and sensitivity analyses and by meta-regression. Dose-response was evaluated in stratified dose or intake analyses. Publication bias assessments were performed. Among RCTs, there was a nonstatistically significant reduction in CHD risk with EPA+DHA provision (SRRE=0.94; 95% CI, 0.85-1.05). Subgroup analyses of data from RCTs indicated a statistically significant CHD risk reduction with EPA+DHA provision among higher-risk populations, including participants with elevated triglyceride levels (SRRE=0.84; 95% CI, 0.72-0.98) and elevated low-density lipoprotein cholesterol (SRRE=0.86; 95% CI, 0.76-0.98). Meta-analysis of data from prospective cohort studies resulted in a statistically significant SRRE of 0.82 (95% CI, 0.74-0.92) for higher intakes of EPA+DHA and risk of any CHD event. Results indicate that EPA+DHA may be associated with reducing CHD risk, with a greater benefit observed among higher-risk populations in RCTs. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
Thermal analysis of underground power cable system
NASA Astrophysics Data System (ADS)
Rerak, Monika; Ocłoń, Paweł
2017-10-01
The paper presents the application of Finite Element Method in thermal analysis of underground power cable system. The computations were performed for power cables buried in-line in the ground at a depth of 2 meters. The developed mathematical model allows determining the two-dimensional temperature distribution in the soil, thermal backfill and power cables. The simulations studied the effect of soil and cable backfill thermal conductivity on the maximum temperature of the cable conductor. Also, the effect of cable diameter on the temperature of cable core was studied. Numerical analyses were performed based on a program written in MATLAB.
NASA Astrophysics Data System (ADS)
Rizvi, Zarghaam Haider; Shrestha, Dinesh; Sattari, Amir S.; Wuttke, Frank
2018-02-01
Macroscopic parameters such as effective thermal conductivity (ETC) is an important parameter which is affected by micro and meso level behaviour of particulate materials, and has been extensively examined in the past decades. In this paper, a new lattice based numerical model is developed to predict the ETC of sand and modified high thermal backfill material for energy transportation used for underground power cables. 2D and 3D simulations are performed to analyse and detect differences resulting from model simplification. The thermal conductivity of the granular mixture is determined numerically considering the volume and the shape of the each constituting portion. The new numerical method is validated with transient needle measurements and the existing theoretical and semi empirical models for thermal conductivity prediction sand and the modified backfill material for dry condition. The numerical prediction and the measured values are in agreement to a large extent.
Acoustic dipole radiation model for magnetoacoustic tomography with magnetic induction
NASA Astrophysics Data System (ADS)
Li, Yi-Ling; Ma, Qing-Yu; Zhang, Dong; Xia, Rong-Min
2011-08-01
An acoustic dipole radiation model for magnetoacoustic tomography with magnetic induction (MAT-MI) is proposed, based on the analyses of one-dimensional tissue vibration, three-dimensional acoustic dipole radiation and acoustic waveform detection with a planar piston transducer. The collected waveforms provide information about the conductivity boundaries in various vibration intensities and phases due to the acoustic dipole radiation pattern. Combined with the simplified back projection algorithm, the conductivity configuration of the measured layer in terms of shape and size can be reconstructed with obvious border stripes. The numerical simulation is performed for a two-layer cylindrical phantom model and it is also verified by the experimental results of MAT-MI for a tissue-like sample phantom. The proposed model suggests a potential application of conductivity differentiation and provides a universal basis for the further study of conductivity reconstruction for MAT-MI.
NASA Technical Reports Server (NTRS)
Stephens, Chad; Kennedy, Kellie; Napoli, Nicholas; Demas, Matthew; Barnes, Laura; Crook, Brenda; Williams, Ralph; Last, Mary Carolyn; Schutte, Paul
2017-01-01
Human-autonomous systems have the potential to mitigate pilot cognitive impairment and improve aviation safety. A research team at NASA Langley conducted an experiment to study the impact of mild normobaric hypoxia induction on aircraft pilot performance and psychophysiological state. A within-subjects design involved non-hypoxic and hypoxic exposures while performing three 10-minute tasks. Results indicated the effect of 15,000 feet simulated altitude did not induce significant performance decrement but did produce increase in perceived workload. Analyses of psychophysiological responses evince the potential of biomarkers for hypoxia onset. This study represents on-going work at NASA intending to add to the current knowledge of psychophysiologically-based input to automation to increase aviation safety. Analyses involving coupling across physiological systems and wavelet transforms of cortical activity revealed patterns that can discern between the simulated altitude conditions. Specifically, multivariate entropy of ECG/Respiration components were found to be significant predictors (p< 0.02) of hypoxia. Furthermore, in EEG, there was a significant decrease in mid-level beta (15.19-18.37Hz) during the hypoxic condition in thirteen of sixteen sites across the scalp. Task performance was not appreciably impacted by the effect of 15,000 feet simulated altitude. Analyses of psychophysiological responses evince the potential of biomarkers for mild hypoxia onset.The potential for identifying shifts in underlying cortical and physiological systems could serve as a means to identify the onset of deteriorated cognitive state. Enabling such assessment in future flightdecks could permit increasingly autonomous systems-supported operations. Augmenting human operator through assessment of cognitive impairment has the potential to further improve operator performance and mitigate human error in safety critical contexts. This study represents ongoing work at NASA intending to add to the current knowledge of psychophysiologically-based input to automation to increase aviation safety.
Conduct problems trajectories and psychosocial outcomes: a systematic review and meta-analysis.
Bevilacqua, Leonardo; Hale, Daniel; Barker, Edward D; Viner, Russell
2017-10-06
There is increasing evidence that youth who follow the early onset persistent (EOP), adolescent-onset (AO) and childhood-limited (CL) trajectories of conduct problems show varying patterns of health, mental health, educational, and social outcomes in adulthood. However, there has been no systematic review and meta-analysis on outcomes associated with different conduct problems trajectories. We systematically reviewed the literature of longitudinal studies considering outcomes of three conduct problems trajectories: EOP, AO, and CL compared with individuals with low levels of conduct problems (low). We performed a series of meta-analyses comparing each trajectory to the low group for eight different outcomes in early adulthood or later. Thirteen studies met our inclusion criteria. Outcomes were mental health (depression), cannabis use, alcohol use, self-reported aggression, official records of antisocial behaviour, poor general health, poor education, and poor employment. Overall, EOP individuals showed significant higher risk of poor outcome followed by AO individuals, CL individuals, and finally participants in the low group. All conduct problems trajectories showed higher risk of poor psychosocial outcomes compared to the low group, but the magnitude of risk differed across trajectories, with a general trend for the EOP to perform significantly worse, followed by the AO and CL. Early intervention is recommended across domains to maximise likelihood of desistance from antisocial behaviour and improvement on several psychosocial outcomes.
Use of safety management practices for improving project performance.
Cheng, Eddie W L; Kelly, Stephen; Ryan, Neal
2015-01-01
Although site safety has long been a key research topic in the construction field, there is a lack of literature studying safety management practices (SMPs). The current research, therefore, aims to test the effect of SMPs on project performance. An empirical study was conducted in Hong Kong and the data collected were analysed with multiple regression analysis. Results suggest that 3 of the 15 SMPs, which were 'safety committee at project/site level', 'written safety policy', and 'safety training scheme' explained the variance in project performance significantly. Discussion about the impact of these three SMPs on construction was provided. Assuring safe construction should be an integral part of a construction project plan.
Using the stepladder technique to facilitate the performance of audioconferencing groups.
Rogelberg, Steven G; O'Connor, Matthew S; Sederburg, Matthew
2002-10-01
Organizational workforces are becoming increasingly dispersed. To facilitate communications among individuals or groups of people located in a number of different locations, teleconferencing technologies, such as audioconferencing, have been developed. The authors examined whether a structural group intervention, the stepladder technique, can facilitate the task performance of 4-person groups (n = 52) when using audioconferencing. Consistent with research conducted on face-to-face groups, the stepladder technique was found to facilitate the decision-making performance of groups interacting via audioconference. The authors postulated that certain structural elements of the stepladder technique compensate for obstacles inherent in nonvisual communications. Supplementary analyses examined best member influence and the existence of order of entry effects into the stepladder process.
Developments in REDES: The rocket engine design expert system
NASA Technical Reports Server (NTRS)
Davidian, Kenneth O.
1990-01-01
The Rocket Engine Design Expert System (REDES) is being developed at the NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP, a nozzle design program named RAO, a regenerative cooling channel performance evaluation code named RTE, and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES is built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.
Developments in REDES: The Rocket Engine Design Expert System
NASA Technical Reports Server (NTRS)
Davidian, Kenneth O.
1990-01-01
The Rocket Engine Design Expert System (REDES) was developed at NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP; a nozzle design program named RAO; a regenerative cooling channel performance evaluation code named RTE; and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES was built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
This report was prepared at the request of the Lawrence Livermore Laboratory (LLL) to provide background information for analyzing soil-structure interaction by the frequency-independent impedance function approach. LLL is conducting such analyses as part of its seismic review of selected operating plants under the Systematic Evaluation Program for the US Nuclear Regulatory Commission. The analytical background and basic assumptionsof the impedance function theory are briefly reviewed, and the role of radiation damping in soil-structure interaction analysis is discussed. The validity of modeling soil-structure interaction by using frequency-independent functions is evaluated based on data from several field tests. Finally, the recommendedmore » procedures for performing soil-structure interaction analyses are discussed with emphasis on the modal superposition method.« less
Kohlmann, Alexander; Kipps, Thomas J; Rassenti, Laura Z; Downing, James R; Shurtleff, Sheila A; Mills, Ken I; Gilkes, Amanda F; Hofmann, Wolf-Karsten; Basso, Giuseppe; Dell’Orto, Marta Campo; Foà, Robin; Chiaretti, Sabina; De Vos, John; Rauhut, Sonja; Papenhausen, Peter R; Hernández, Jesus M; Lumbreras, Eva; Yeoh, Allen E; Koay, Evelyn S; Li, Rachel; Liu, Wei-min; Williams, Paul M; Wieczorek, Lothar; Haferlach, Torsten
2008-01-01
Gene expression profiling has the potential to enhance current methods for the diagnosis of haematological malignancies. Here, we present data on 204 analyses from an international standardization programme that was conducted in 11 laboratories as a prephase to the Microarray Innovations in LEukemia (MILE) study. Each laboratory prepared two cell line samples, together with three replicate leukaemia patient lysates in two distinct stages: (i) a 5-d course of protocol training, and (ii) independent proficiency testing. Unsupervised, supervised, and r2 correlation analyses demonstrated that microarray analysis can be performed with remarkably high intra-laboratory reproducibility and with comparable quality and reliability. PMID:18573112
Battery testing at Argonne National Laboratory
NASA Astrophysics Data System (ADS)
Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.
Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis & Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, in a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during FY-92 on both single cells and multi-cell modules that encompass six battery technologies (Na/S, Li/FeS, Ni/Metal-Hydride, Ni/Zn, Ni/Cd, Ni/Fe). These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most promising R&D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R&D programs, a comparison of battery technologies, and basic data for modeling.
NASA Astrophysics Data System (ADS)
Kosch, M.; Nielsen, E.
Two bi-static VHF radar systems STARE and SABRE have been employed to estimate ionospheric electric field distributions in the geomagnetic latitude range 61 1 - 69 3 degrees over Scandinavia corresponding to the global Region 2 current system 173 days of data from all four radars have been analysed during the period 1982 to 1986 The average magnetic field-aligned currents have been computed as a function of the Kp and Ae indices using an empirical model of ionospheric Pedersen and Hall conductance taking into account conductance gradients The divergence of horizontal Pedersen currents and Hall conductance gradients have approximately the same importance for generating the Region 2 field-aligned currents Pedersen conductance gradients have a significant modifying effect A case study of field-aligned currents has been performed using the STARE radar system to obtain the instantaneous ionospheric electric field distribution in the vicinity of an auroral arc The instantaneous Hall conductance was estimated from the Scandinavian Magnetometer Array This study clearly shows that even for quiet steady state geomagnetic conditions conductance gradients are important modifiers of magnetic field-aligned currents
Gressier, Florence; Porcelli, Stefano; Calati, Raffaella; Serretti, Alessandro
2016-02-01
Clozapine (CLZ) is the prototype atypical antipsychotic and it has many advantages over other antipsychotic drugs. Several data suggest that both CLZ response and induced weight gain are strongly determined by genetic variability. However, results remain mainly inconclusive. We aim to review the literature data about pharmacogenetics studies on CLZ efficacy, focusing on pharmacodynamic genes. Further, we performed meta-analyses on response when at least three studies for each polymorphism were available. Sensitivity analyses were conducted on Caucasian population when feasible. Electronic literature search was performed to identify pertinent studies published until May 2014 using PubMed, ISI Web of Knowledge and PsycINFO databases. For meta-analyses, data were entered and analyzed through RevMan version 5.2 using a random-effect model. Our literature search yielded 9266 articles on CLZ; among these, we identified 59 pertinent pharmacogenetic studies. Genotype data were retrieved for 14 polymorphisms in 9 genes. Among these, we had available data from at least three independent samples for 8 SNPs in 6 genes to perform meta-analyses: DRD2 rs1799732, DRD3 rs6280, HTR2A rs6313, rs6311, rs6314, HTR2C rs6318, HTR3A rs1062613, TNFa rs1800629. Although literature review provided conflicting results, in meta-analyses three genetic variants within serotonin genes resulted associated to CLZ response: rs6313 and rs6314 within HTR2A gene and rs1062613 within HT3A gene. On the other hand, no clear finding emerged for CLZ-induced weight gain. Our results suggest a possible serotonergic modulation of CLZ clinical response. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.
Geothermal reservoir simulation of hot sedimentary aquifer system using FEFLOW®
NASA Astrophysics Data System (ADS)
Nur Hidayat, Hardi; Gala Permana, Maximillian
2017-12-01
The study presents the simulation of hot sedimentary aquifer for geothermal utilization. Hot sedimentary aquifer (HSA) is a conduction-dominated hydrothermal play type utilizing deep aquifer, which is heated by near normal heat flow. One of the examples of HSA is Bavarian Molasse Basin in South Germany. This system typically uses doublet wells: an injection and production well. The simulation was run for 3650 days of simulation time. The technical feasibility and performance are analysed in regards to the extracted energy from this concept. Several parameters are compared to determine the model performance. Parameters such as reservoir characteristics, temperature information and well information are defined. Several assumptions are also defined to simplify the simulation process. The main results of the simulation are heat period budget or total extracted heat energy, and heat rate budget or heat production rate. Qualitative approaches for sensitivity analysis are conducted by using five parameters in which assigned lower and higher value scenarios.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-22
... parties. DOE is planning to conduct in-depth technical analyses in the following areas: (1) Engineering..., analyses, and processes it anticipates using to determine whether to amend energy conservation standards... impacts, and (10) regulatory impacts. DOE will also conduct several other analyses that support those...
Boström, Ingrid M; Nyman, Görel C; Lord, Peter E; Häggström, Jens; Jones, Bernt E V; Bohlin, Henrik P
2002-05-01
To investigate effects of IV administered carprofen on indices of renal function and results of serum biochemical and hematologic analyses in dogs anesthetized with acepromazine-thiopentone-isoflurane that had low blood pressure during anesthesia. 6 healthy Beagles. A randomized crossover study was conducted, using the following treatments: saline (0.9% NaCl solution)-saline, saline-carprofen, and carprofen-saline. Saline (0.08 ml/kg) and carprofen (4 mg/kg) were administered IV. The first treatment was administered 30 minutes before induction of anesthesia and immediately before administration of acepromazine (0.1 mg/kg, IM). Anesthesia was induced with thiopentone (25 mg/ml, IV) and maintained with inspired isoflurane (2% in oxygen). The second treatment was administered 30 minutes after onset of inhalation anesthesia. Blood gases, circulation, and ventilation were monitored. Renal function was assessed by glomerular filtration rate (GFR), using scintigraphy, serum biochemical analyses, and urinalysis. Hematologic analysis was performed. Statistical analysis was conducted, using ANOVA or Friedman ANOVA. Values did not differ significantly among the 3 treatments. For all treatments, sedation and anesthesia caused changes in results of serum biochemical and hematologic analyses, a decrease in mean arterial blood pressure to 65 mm Hg, an increase of 115 pmol/L in angiotensin II concentration, and an increase of 100 seconds in time required to reach maximum activity counts during scintigraphy. Carprofen administered IV before or during anesthesia did not cause detectable significant adverse effects on renal function or results of serum biochemical and hematologic analyses in healthy Beagles with low blood pressure during anesthesia.
Testing search strategies for systematic reviews in the Medline literature database through PubMed.
Volpato, Enilze S N; Betini, Marluci; El Dib, Regina
2014-04-01
A high-quality electronic search is essential in ensuring accuracy and completeness in retrieved records for the conducting of a systematic review. We analysed the available sample of search strategies to identify the best method for searching in Medline through PubMed, considering the use or not of parenthesis, double quotation marks, truncation and use of a simple search or search history. In our cross-sectional study of search strategies, we selected and analysed the available searches performed during evidence-based medicine classes and in systematic reviews conducted in the Botucatu Medical School, UNESP, Brazil. We analysed 120 search strategies. With regard to the use of phrase searches with parenthesis, there was no difference between the results with and without parenthesis and simple searches or search history tools in 100% of the sample analysed (P = 1.0). The number of results retrieved by the searches analysed was smaller using double quotations marks and using truncation compared with the standard strategy (P = 0.04 and P = 0.08, respectively). There is no need to use phrase-searching parenthesis to retrieve studies; however, we recommend the use of double quotation marks when an investigator attempts to retrieve articles in which a term appears to be exactly the same as what was proposed in the search form. Furthermore, we do not recommend the use of truncation in search strategies in the Medline via PubMed. Although the results of simple searches or search history tools were the same, we recommend using the latter.
Tellegen, Cassandra L; Sanders, Matthew R
2013-05-01
This systematic review and meta-analysis evaluated the treatment effects of a behavioral family intervention, Stepping Stones Triple P (SSTP) for parents of children with disabilities. SSTP is a system of five intervention levels of increasing intensity and narrowing population reach. Twelve studies, including a total of 659 families, met eligibility criteria. Studies needed to have evaluated SSTP, be written in English or German, contribute original data, and have sufficient data for analyses. No restrictions were placed on study design. A series of meta-analyses were performed for seven different outcome categories. Analyses were conducted on the combination of all four levels of SSTP for which evidence exists (Levels 2-5), and were also conducted separately for each level of SSTP. Significant moderate effect sizes were found for all levels of SSTP for reducing child problems, the primary outcome of interest. On secondary outcomes, significant overall effect sizes were found for parenting styles, parenting satisfaction and efficacy, parental adjustment, parental relationship, and observed child behaviors. No significant treatment effects were found for observed parenting behaviors. Moderator analyses showed no significant differences in effect sizes across the levels of SSTP intervention, with the exception of child observations. Risk of bias within and across studies was assessed. Analyses suggested that publication bias and selective reporting bias were not likely to have heavily influenced the findings. The overall evidence base supported the effectiveness of SSTP as an intervention for improving child and parent outcomes in families of children with disabilities. Limitations and future research directions are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
Experimental measurement of the plasma conductivity of Z93 and Z93P thermal control paint
NASA Technical Reports Server (NTRS)
Hillard, G. Barry
1993-01-01
Two samples each of Z93 and Z93P thermal control paint were exposed to a simulated space environment in a plasma chamber. The samples were biased through a series of voltages ranging from -200 volts to +300 volts and electron and ion currents measured. By comparing the currents to those of pure metal samples of the same size and shape, the conductivity of the samples was calculated. Measured conductivity was dependent on the bias potential in all cases. For Z93P, conductivity was approximately constant over much of the bias range and we find a value of 0.5 micro-mhos per square meter for both electron and ion current. For Z93, the dependence on bias was much more pronounced but conductivity can be said to be approximately one order of magnitude larger. In addition to presenting these results, this report documents all of the experimental data as well as the statistical analyses performed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dong, Lihua; Cui, Jingkun; Tang, Fengjiao
Purpose: Studies of the association between ataxia telangiectasia–mutated (ATM) gene polymorphisms and acute radiation injuries are often small in sample size, and the results are inconsistent. We conducted the first meta-analysis to provide a systematic review of published findings. Methods and Materials: Publications were identified by searching PubMed up to April 25, 2014. Primary meta-analysis was performed for all acute radiation injuries, and subgroup meta-analyses were based on clinical endpoint. The influence of sample size and radiation injury incidence on genetic effects was estimated in sensitivity analyses. Power calculations were also conducted. Results: The meta-analysis was conducted on the ATMmore » polymorphism rs1801516, including 5 studies with 1588 participants. For all studies, the cut-off for differentiating cases from controls was grade 2 acute radiation injuries. The primary meta-analysis showed a significant association with overall acute radiation injuries (allelic model: odds ratio = 1.33, 95% confidence interval: 1.04-1.71). Subgroup analyses detected an association between the rs1801516 polymorphism and a significant increase in urinary and lower gastrointestinal injuries and an increase in skin injury that was not statistically significant. There was no between-study heterogeneity in any meta-analyses. In the sensitivity analyses, small studies did not show larger effects than large studies. In addition, studies with high incidence of acute radiation injuries showed larger effects than studies with low incidence. Power calculations revealed that the statistical power of the primary meta-analysis was borderline, whereas there was adequate power for the subgroup analysis of studies with high incidence of acute radiation injuries. Conclusions: Our meta-analysis showed a consistency of the results from the overall and subgroup analyses. We also showed that the genetic effect of the rs1801516 polymorphism on acute radiation injuries was dependent on the incidence of the injury. These support the evidence of an association between the rs1801516 polymorphism and acute radiation injuries, encouraging further research of this topic.« less
Prol, Fabricio S; Camargo, Paulo O; Muella, Marcio T A H
2017-01-01
The incomplete geometrical coverage of the Global Navigation Satellite System (GNSS) makes the ionospheric tomographic system an ill-conditioned problem for ionospheric imaging. In order to detect the principal limitations of the ill-conditioned tomographic solutions, numerical simulations of the ionosphere are under constant investigation. In this paper, we show an investigation of the accuracy of Algebraic Reconstruction Technique (ART) and Multiplicative ART (MART) for performing tomographic reconstruction of Chapman profiles using a simulated optimum scenario of GNSS signals tracked by ground-based receivers. Chapman functions were used to represent the ionospheric morphology and a set of analyses was conducted to assess ART and MART performance for estimating the Total Electron Content (TEC) and parameters that describes the Chapman function. The results showed that MART performed better in the reconstruction of the electron density peak and ART gave a better representation for estimating TEC and the shape of the ionosphere. Since we used an optimum scenario of the GNSS signals, the analyses indicate the intrinsic problems that may occur with ART and MART to recover valuable information for many applications of Telecommunication, Spatial Geodesy and Space Weather.
Pedroza, Claudia; Han, Weilu; Thanh Truong, Van Thi; Green, Charles; Tyson, Jon E
2018-01-01
One of the main advantages of Bayesian analyses of clinical trials is their ability to formally incorporate skepticism about large treatment effects through the use of informative priors. We conducted a simulation study to assess the performance of informative normal, Student- t, and beta distributions in estimating relative risk (RR) or odds ratio (OR) for binary outcomes. Simulation scenarios varied the prior standard deviation (SD; level of skepticism of large treatment effects), outcome rate in the control group, true treatment effect, and sample size. We compared the priors with regards to bias, mean squared error (MSE), and coverage of 95% credible intervals. Simulation results show that the prior SD influenced the posterior to a greater degree than the particular distributional form of the prior. For RR, priors with a 95% interval of 0.50-2.0 performed well in terms of bias, MSE, and coverage under most scenarios. For OR, priors with a wider 95% interval of 0.23-4.35 had good performance. We recommend the use of informative priors that exclude implausibly large treatment effects in analyses of clinical trials, particularly for major outcomes such as mortality.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Karmi, S.; Madden, J.; Borsetti, R.
1996-01-05
This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Barter Island radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Karmi, S.
1996-02-19
This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Point Barrow radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frazier, William; Baur, Gary
2015-11-03
The 1998 Interim Long-Term Surveillance Plan for the Cheney Disposal Site Near Grand Junction, Colorado, requires annual monitoring to assess the performance of the disposal cell. Monitoring wells 0731, 0732 and 0733 were sampled as specified in the plan. Sampling and analyses were conducted in accordance with Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites.
2009-09-01
demonstrate competence” ( Jones , 2006). Most organizations conduct performance management for their employees with actions such as, setting goals...take the 14 form of comprehensive questionnaires, SWOT analyses or diagnostic models and include a comparison of results to various best practices...procnet.pica.army.mil/ Jones , R. (2006). CIDA Organizational Assessment Guide. Retrieved on March 1, 2009 from: http://www.acdi-cida.gc.ca/CIDAWEB
Cost and Training Effectiveness Analysis Performance Guide
1980-07-23
U8 tämat^iimiäimmm .. ·•· THIS DOCUMENT IS BEST QUALITY AVAILABLE. THE COPY FURNISHED TO DTIC CONTAINED A SIGNIFICANT NUMBER OF PAGES WHICH...Effectiveness Analyses (CTEA). It provides strategies for planning the CTEA and provides illustrative methods to be adapted to the particular data...Resolution D. Strategies for Conducting the CTEA E. Summary III Process Procedures A. Generation of Task List 1. DIVAD Gun 2. Improved Hawk vHawk PIP
Ares I-X Upper Stage Simulator Residual Stress Analysis
NASA Technical Reports Server (NTRS)
Raju, Ivatury S.; Brust, Frederick W.; Phillips, Dawn R.; Cheston, Derrick
2008-01-01
The structural analyses described in the present report were performed in support of the NASA Engineering and Safety Center (NESC) Critical Initial Flaw Size (CIFS) assessment for the Ares I-X Upper Stage Simulator (USS) common shell segment. An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). The Ares system of space launch vehicles is the US National Aeronautics and Space Administration s plan for replacement of the aging space shuttle. The new Ares space launch system is somewhat of a combination of the space shuttle system and the Saturn launch vehicles used prior to the shuttle. Here, a series of weld analyses are performed to determine the residual stresses in a critical region of the USS. Weld residual stresses both increase constraint and mean stress thereby having an important effect on fatigue and fracture life. The results of this effort served as one of the critical load inputs required to perform a CIFS assessment of the same segment.
Numerical investigation of performance of vane-type propellant management device by VOF methods
NASA Astrophysics Data System (ADS)
Liu, J. T.; Zhou, C.; Wu, Y. L.; Zhuang, B. T.; Li, Y.
2015-01-01
The orbital propellant management performance of the vane-type tank is so important for the propellant system and it determines the lifetime of the satellite. The propellant in the tank can be extruded by helium gas. To study the two phase distribution in the vane-type surface tension tank and the capability of the vane-type propellant management device (PMD), a large volume vane-type surface tension tank is analysed using 3-D unsteady numerical simulations. VOF methods are used to analyse the location of the interface of the two phase. Performances of the propellant acquisition vanes and propellant refillable reservoir in the tank are investigated. The flow conductivity of the propellant acquisition vanes and the liquid storage capacity of propellant refillable reservoir can be affected by the value of the gravity and the volume of the propellant in the tank. To avoid the large resistance causing by surface tension in an outflow of a small hole, the design of the vanes in a propellant refillable reservoir should have suitable space.
Steady-State Thermal-Hydraulics Analyses for the Conversion of BR2 to Low Enriched Uranium Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Licht, J.; Bergeron, A.; Dionne, B.
The code PLTEMP/ANL version 4.2 was used to perform the steady-state thermal-hydraulic analyses of the BR2 research reactor for conversion from Highly-Enriched to Low Enriched Uranium fuel (HEU and LEU, respectively). Calculations were performed to evaluate different fuel assemblies with respect to the onset of nucleate boiling (ONB), flow instability (FI), critical heat flux (CHF) and fuel temperature at beginning of cycle conditions. The fuel assemblies were characteristic of fresh fuel (0% burnup), highest heat flux (16% burnup), highest power (32% burnup) and highest burnup (46% burnup). Results show that the high heat flux fuel element is limiting for ONB,more » FI, and CHF, for both HEU and LEU fuel, but that the high power fuel element produces similar margin in a few cases. The maximum fuel temperature similarly occurs in both the high heat flux and high power fuel assemblies for both HEU and LEU fuel. A sensitivity study was also performed to evaluate the variation in fuel temperature due to uncertainties in the thermal conductivity degradation associated with burnup.« less
Integrated Flight Performance Analysis of a Launch Abort System Concept
NASA Technical Reports Server (NTRS)
Tartabini, Paul V.
2007-01-01
This paper describes initial flight performance analyses conducted early in the Orion Project to support concept feasibility studies for the Crew Exploration Vehicle s Launch Abort System (LAS). Key performance requirements that significantly affect abort capability are presented. These requirements have implications on sizing the Abort Motor, tailoring its thrust profile to meet escape requirements for both launch pad and high drag/high dynamic pressure ascent aborts. Additional performance considerations are provided for the Attitude Control Motor, a key element of the Orion LAS design that eliminates the need for ballast and provides performance robustness over a passive control approach. Finally, performance of the LAS jettison function is discussed, along with implications on Jettison Motor sizing and the timing of the jettison event during a nominal mission. These studies provide an initial understanding of LAS performance that will continue to evolve as the Orion design is matured.
Developmental fMRI study of episodic verbal memory encoding in children.
Maril, A; Davis, P E; Koo, J J; Reggev, N; Zuckerman, M; Ehrenfeld, L; Mulkern, R V; Waber, D P; Rivkin, M J
2010-12-07
Understanding the maturation and organization of cognitive function in the brain is a central objective of both child neurology and developmental cognitive neuroscience. This study focuses on episodic memory encoding of verbal information by children, a cognitive domain not previously studied using fMRI. Children from 7 to 19 years of age were scanned at 1.5-T field strength using event-related fMRI while performing a novel verbal memory encoding paradigm in which words were incidentally encoded. A subsequent memory analysis was performed. SPM2 was utilized for whole brain and region-of-interest analyses of data. Both whole-sample intragroup analyses and intergroup analyses of the sample divided into 2 subgroups by age were conducted. Importantly, behavioral memory performance was equal across the age range of children studied. Encoding-related activation in the left hippocampus and bilateral basal ganglia declined as age increased. In addition, while robust blood oxygen level-dependent signal was found in left prefrontal cortex with task performance, no encoding-related age-modulated prefrontal activation was observed in either hemisphere. These data are consistent with a developmental pattern of verbal memory encoding function in which left hippocampal and bilateral basal ganglionic activations are more robust earlier in childhood but then decline with age. No encoding-related activation was found in prefrontal cortex which may relate to this region's recognized delay in biologic maturation in humans. These data represent the first fMRI demonstration of verbal encoding function in children and are relevant developmentally and clinically.
NASA Astrophysics Data System (ADS)
Dong, Leng; Chen, Yan; Dias, Sarah; Stone, William; Dias, Joseph; Rout, John; Gale, Alastair G.
2017-03-01
Visual search techniques and FROC analysis have been widely used in radiology to understand medical image perceptual behaviour and diagnostic performance. The potential of exploiting the advantages of both methodologies is of great interest to medical researchers. In this study, eye tracking data of eight dental practitioners was investigated. The visual search measures and their analyses are considered here. Each participant interpreted 20 dental radiographs which were chosen by an expert dental radiologist. Various eye movement measurements were obtained based on image area of interest (AOI) information. FROC analysis was then carried out by using these eye movement measurements as a direct input source. The performance of FROC methods using different input parameters was tested. The results showed that there were significant differences in FROC measures, based on eye movement data, between groups with different experience levels. Namely, the area under the curve (AUC) score evidenced higher values for experienced group for the measurements of fixation and dwell time. Also, positive correlations were found for AUC scores between the eye movement data conducted FROC and rating based FROC. FROC analysis using eye movement measurements as input variables can act as a potential performance indicator to deliver assessment in medical imaging interpretation and assess training procedures. Visual search data analyses lead to new ways of combining eye movement data and FROC methods to provide an alternative dimension to assess performance and visual search behaviour in the area of medical imaging perceptual tasks.
Nonlinear soil parameter effects on dynamic embedment of offshore pipeline on soft clay
NASA Astrophysics Data System (ADS)
Yu, Su Young; Choi, Han Suk; Lee, Seung Keon; Park, Kyu-Sik; Kim, Do Kyun
2015-06-01
In this paper, the effects of nonlinear soft clay on dynamic embedment of offshore pipeline were investigated. Seabed embedment by pipe-soil interactions has impacts on the structural boundary conditions for various subsea structures such as pipeline, riser, pile, and many other systems. A number of studies have been performed to estimate real soil behavior, but their estimation of seabed embedment has not been fully identified and there are still many uncertainties. In this regards, comparison of embedment between field survey and existing empirical models has been performed to identify uncertainties and investigate the effect of nonlinear soil parameter on dynamic embedment. From the comparison, it is found that the dynamic embedment with installation effects based on nonlinear soil model have an influence on seabed embedment. Therefore, the pipe embedment under dynamic condition by nonlinear parameters of soil models was investigated by Dynamic Embedment Factor (DEF) concept, which is defined as the ratio of the dynamic and static embedment of pipeline, in order to overcome the gap between field embedment and currently used empirical and numerical formula. Although DEF through various researches is suggested, its range is too wide and it does not consider dynamic laying effect. It is difficult to find critical parameters that are affecting to the embedment result. Therefore, the study on dynamic embedment factor by soft clay parameters of nonlinear soil model was conducted and the sensitivity analyses about parameters of nonlinear soil model were performed as well. The tendency on dynamic embedment factor was found by conducting numerical analyses using OrcaFlex software. It is found that DEF was influenced by shear strength gradient than other factors. The obtained results will be useful to understand the pipe embedment on soft clay seabed for applying offshore pipeline designs such as on-bottom stability and free span analyses.
Cloud-based bioinformatics workflow platform for large-scale next-generation sequencing analyses
Liu, Bo; Madduri, Ravi K; Sotomayor, Borja; Chard, Kyle; Lacinski, Lukasz; Dave, Utpal J; Li, Jianqiang; Liu, Chunchen; Foster, Ian T
2014-01-01
Due to the upcoming data deluge of genome data, the need for storing and processing large-scale genome data, easy access to biomedical analyses tools, efficient data sharing and retrieval has presented significant challenges. The variability in data volume results in variable computing and storage requirements, therefore biomedical researchers are pursuing more reliable, dynamic and convenient methods for conducting sequencing analyses. This paper proposes a Cloud-based bioinformatics workflow platform for large-scale next-generation sequencing analyses, which enables reliable and highly scalable execution of sequencing analyses workflows in a fully automated manner. Our platform extends the existing Galaxy workflow system by adding data management capabilities for transferring large quantities of data efficiently and reliably (via Globus Transfer), domain-specific analyses tools preconfigured for immediate use by researchers (via user-specific tools integration), automatic deployment on Cloud for on-demand resource allocation and pay-as-you-go pricing (via Globus Provision), a Cloud provisioning tool for auto-scaling (via HTCondor scheduler), and the support for validating the correctness of workflows (via semantic verification tools). Two bioinformatics workflow use cases as well as performance evaluation are presented to validate the feasibility of the proposed approach. PMID:24462600
Cloud-based bioinformatics workflow platform for large-scale next-generation sequencing analyses.
Liu, Bo; Madduri, Ravi K; Sotomayor, Borja; Chard, Kyle; Lacinski, Lukasz; Dave, Utpal J; Li, Jianqiang; Liu, Chunchen; Foster, Ian T
2014-06-01
Due to the upcoming data deluge of genome data, the need for storing and processing large-scale genome data, easy access to biomedical analyses tools, efficient data sharing and retrieval has presented significant challenges. The variability in data volume results in variable computing and storage requirements, therefore biomedical researchers are pursuing more reliable, dynamic and convenient methods for conducting sequencing analyses. This paper proposes a Cloud-based bioinformatics workflow platform for large-scale next-generation sequencing analyses, which enables reliable and highly scalable execution of sequencing analyses workflows in a fully automated manner. Our platform extends the existing Galaxy workflow system by adding data management capabilities for transferring large quantities of data efficiently and reliably (via Globus Transfer), domain-specific analyses tools preconfigured for immediate use by researchers (via user-specific tools integration), automatic deployment on Cloud for on-demand resource allocation and pay-as-you-go pricing (via Globus Provision), a Cloud provisioning tool for auto-scaling (via HTCondor scheduler), and the support for validating the correctness of workflows (via semantic verification tools). Two bioinformatics workflow use cases as well as performance evaluation are presented to validate the feasibility of the proposed approach. Copyright © 2014 Elsevier Inc. All rights reserved.
The relative age effect among elite youth competitive swimmers.
Costa, Aldo M; Marques, Mário C; Louro, Hugo; Ferreira, Sandra S; Marinho, Daniel A
2013-01-01
The aim of this study was to analyse the relative age effect (RAE) in competitive swimming. The best 50 Portuguese swimmers (12- to 18-year-olds) for the main individual swimming pool events of both genders were considered. Analysis was conducted on 7813 swimming event participants, taking account of respective swimmer birth dates and the Fédération Internationale de Natation points gained. Differences in the distribution of birth dates by quarter year were determined using the Chi-square. A one-way analysis of variance ANOVA was used to test for differences measured in points between individuals by quarterly birth year intervals. A two-way analysis of variance ANOVA was also conducted to test the interaction between gender and seasonal birth date with regard to performance. The results show an inequitable distribution (p<0.01) of birth dates by quarter for almost all age groups and both genders. However, the distribution of birth dates by quarter for each considered swim event shows that RAE seems to exist only for 12-year-old females and 12- to 15-year-old males. Analysing mean swimming performance, post-hoc results (p<0.01) show no consistency in RAE. Higher performance occurs among older swimmers only in 100 m butterfly (female 1998, 1st≠2nd quarter, p=0.003). The results also show no interaction between gender and seasonal birth date (p<0.01). Findings of this study show that a higher number of swimmers, particular males, are born in the first two quarters of the year, although there is mostly no effect of seasonal birth date on performance differences within the top 50 swimmers.
Bylow, Kathryn; Hemmerich, Joshua; Mohile, Supriya G.; Stadler, Walter M.; Sajid, Saleha; Dale, William
2010-01-01
Objectives Early androgen deprivation therapy (ADT) has no proven survival advantage in older men with biochemical recurrence (BCR) of prostate cancer (PCa), and it may contribute to geriatric frailty; we tested this hypothesis. Methods We conducted a case-control study of men aged 60+ with BCR on ADT (n=63) versus PCa survivors without recurrence (n=71). Frailty prevalence, “obese” frailty, Short Physical Performance Battery (SPPB) scores and falls were compared. An exploratory analysis of frailty biomarkers (CRP, ESR, hemoglobin, albumin, and total cholesterol) was performed. Summary statistics, univariate and multivariate regression analyses were conducted. Results More patients on ADT were obese (BMI >30; 46.2% vs. 20.6%; p=0.03). There were no statistical differences in SPPB (p=0.41) or frailty (p=0.20). Using a proposed “obese” frailty criteria, 8.7% in ADT group were frail and 56.5% were “prefrail”, compared with 2.9% and 48.8% of controls (p=0.02). Falls in the last year were higher in ADT group (14.3% vs. 2.8%; p=0.02). In analyses controlling for age, clinical characteristics, and comorbidities, the ADT group trended toward significance for “obese” frailty (p = 0.14) and falls (OR = 4.74, p = 0.11). Comorbidity significantly increased the likelihood of “obese” frailty (p=0.01) and falls (OR 2.02, p = 0.01). Conclusions Men with BCR on ADT are frailer using proposed modified “obese” frailty criteria. They may have lower performance status and more falls. A larger, prospective trial is necessary to establish a causal link between ADT use and progression of frailty and disability. PMID:21269665
NASA Astrophysics Data System (ADS)
Hudson, Ross D.; Treagust, David F.
2013-04-01
Background . This study developed from observations of apparent achievement differences between male and female chemistry performances in a state university entrance examination. Male students performed more strongly than female students, especially in higher scores. Apart from the gender of the students, two other important factors that might influence student performance were format of questions (short-answer or multiple-choice) and type of questions (recall or application). Purpose The research question addressed in this study was: Is there a relationship between performance in state university entrance examinations in chemistry and school chemistry examinations and student gender, format of questions - multiple-choice or short-answer, and conceptual level - recall or application? Sample The two sources of data were: (1) secondary analyses of five consecutive years' data published by the examining authority of chemistry examinations, and (2) tests conducted with 192 students which provided information about all aspects of the three variables (question format, question type and gender) under consideration. Design and methods Both sources of data were analysed using ANOVA to compare means for the variables under consideration and the statistical significance of any differences. The data from the tests were also analysed using Rasch analysis to determine differences in gender performance. Results When overall mean data are considered, both male and female students performed better on multiple-choice questions and recall questions than on short-answer questions and application questions, respectively. When overall mean data are considered, male students outperformed female students in both the university entrance and school tests, particularly in the higher scores. When data were analysed with Rasch, there was no statistically significant difference in performance between males and females of equal ability. Conclusions Both male and female students generally perform better on multiple-choice questions than they do on short-answer questions. However, when the questions are matched in terms of difficulty (using Rasch analysis), the differences in performance between multiple-choice and short-answer are quite small. Rasch analysis showed that there was little difference in performance between males and females of equal ability. This study shows that a simple face-value score analysis of relative student performance - in this case, in chemistry - can be deceptive unless the actual abilities of the students concerned, as measured by a tool such as Rasch, are taken into consideration before reaching any conclusion.
Performance of the National Tuberculosis Control Program in the post conflict Liberia.
Desta, Kassaye Tekie; Masango, T E; Nkosi, Zerish Zethu
2018-01-01
Tuberculosis is a major public health problem in Liberia. According to the World Health Organization (WHO), the incidence of tuberculosis in Liberia is significantly increasing from year to year. However, little is known about the performance of the programme and the challenges after the 14 years of civil war which ended in 2003.The purpose of the study was to evaluate the performance of the TB programme of Liberia. The study utilised mixed research design; both quantitative and qualitative methods were used in this study conducted from 2013 to 2014. For the quantitative part of the study, a questionnaire, laboratory performance and eleven years TB programme data (2003-2013) were used. For the performance of tuberculosis laboratory testing, all the 107 functional tuberculosis microscopy centers in Liberia were included. For the qualitative part of the study, an interview of 10 informants and two focus group discussions (FGDs) were also conducted, each comprising of eight people. Themes and subthemes emerged from the two FGDs. Data was analysed in line with the Donabedian model. Quantitative findings were analysed and presented using both descriptive and inferential statistics. The study findings pointed out that there was overall improvement in the performance of the tuberculosis control programme in Liberia from 2003 to 2013. The percentage of cured patients was 60% in 2005 and 62% in 2013. Percentage of treatment completed was 16% in 2005 and 21% in 2013. The case detection rate was 57% and treatment success rate 80% in 2013. The default rate was 11% in 2013. Of the 139 participants, 120 (86%) completed TB treatment while 19 (14%) did not. Between 2003 and 2013, the National Leprosy and Tuberculosis Control Programme (NLTCP) succeeded in restoring the TB services and improving some of the TB treatment outcomes including the Directly observed treatment short courses(DOTS) coverage. Despite these improvements, the TB treatment, laboratory services and human resource capacity lagged behind. The TB programme of Liberia needs to develop new strategies to address its challenges.
Field Quality from Tolerance Stack-up In R&D Quadrupoles for the Advanced Photon Source Upgrade
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, J.; Jaski, M.; Dejus, R.
2016-10-01
The Advanced Photon Source (APS) at Argonne National Laboratory (ANL) is considering upgrading the current double-bend, 7-GeV, 3rd generation storage ring to a 6-GeV, 4th generation storage ring with a Multibend Achromat (MBA) lattice. In this study, a novel method is proposed to determine fabrication and assembly tolerances through a combination of magnetic and mechanical tolerance analyses. Mechanical tolerance stackup analyses using Teamcenter Variation Analysis are carried out to determine the part and assembly level fabrication tolerances. Finite element analyses using OPERA are conducted to estimate the effect of fabrication and assembly errors on the magnetic field of a quadrupolemore » magnet and to determine the allowable tolerances to achieve the desired magnetic performance. Finally, results of measurements in R&D quadrupole prototypes are compared with the analysis results.« less
Moretti, Laura; Di Mascio, Paola; Bellagamba, Simona
2017-01-01
The attention to sustainability-related issues has grown fast in recent decades. The experience gained with these themes reveals the importance of considering this topic in the construction industry, which represents an important sector throughout the world. This work consists on conducting a multicriteria analysis of four cement powders, with the objective of calculating and analysing the environmental, human health and socio-economic effects of their production processes. The economic, technical, environmental and safety performances of the examined powders result from official, both internal and public, documents prepared by the producers. The Analytic Hierarchy Process permitted to consider several indicators (i.e., environmental, human health related and socio-economic parameters) and to conduct comprehensive and unbiased analyses which gave the best, most sustainable cement powder. As assumed in this study, the contribution of each considered parameter to the overall sustainability has a different incidence, therefore the procedure could be used to support on-going sustainability efforts under different conditions. The results also prove that it is not appropriate to regard only one parameter to identify the ‘best’ cement powder, but several impact categories should be considered and analysed if there is an interest for pursuing different, often conflicting interests. PMID:28621754
Associations Between Driving Performance and Engaging in Secondary Tasks: A Systematic Review
Ferdinand, Alva O.
2014-01-01
We conducted a systematic review and meta-analysis of the literature examining the relationship between driving performance and engaging in secondary tasks. We extracted data from abstracts of 206 empirical articles published between 1968 and 2012 and developed a logistic regression model to identify correlates of a detrimental relationship between secondary tasks and driving performance. Of 350 analyses, 80% reported finding a detrimental relationship. Studies using experimental designs were 37% less likely to report a detrimental relationship (P = .014). Studies examining mobile phone use while driving were 16% more likely to find such a relationship (P = .009). Quasi-experiments can better determine the effects of secondary tasks on driving performance and consequently serve to inform policymakers interested in reducing distracted driving and increasing roadway safety. PMID:24432925
Trujillo, Macarena; Bon, Jose; Berjano, Enrique
2017-09-01
(1) To analyse rehydration, thermal convection and increased electrical conductivity as the three phenomena which distinguish the performance of internally cooled electrodes (IC) and internally cooled wet (ICW) electrodes during radiofrequency ablation (RFA), (2) Implement a RFA computer model with an ICW which includes these phenomena and (3) Assess their relative influence on the thermal and electrical tissue response and on the coagulation zone size. A 12-min RFA in liver was modelled using an ICW electrode (17 G, 3 cm tip) by an impedance-control pulsing protocol with a constant current of 1.5 A. A model of an IC electrode was used to compare the ICW electrode performance and the computational results with the experimental results. Rehydration and increased electrical conductivity were responsible for an increase in coagulation zone size and a delay (or absence) in the occurrence of abrupt increases in electrical impedance (roll-off). While the increased electrical conductivity had a remarkable effect on enlarging the coagulation zone (an increase of 0.74 cm for differences in electrical conductivity of 0.31 S/m), rehydration considerably affected the delay in roll-off, which, in fact, was absent with a sufficiently high rehydration level. In contrast, thermal convection had an insignificant effect for the flow rates considered (0.05 and 1 mL/min). Computer results suggest that rehydration and increased electrical conductivity were mainly responsible for the absence of roll-off and increased size of the coagulation zone, respectively, and in combination allow the thermal and electrical performance of ICW electrodes to be modelled during RFA.
Performance and life evaluation of advanced battery technologies for electric vehicle applications
NASA Astrophysics Data System (ADS)
Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.
Advanced battery technology evaluations are performed under simulated electric vehicle (EV) operating conditions at the Argonne Analysis and Diagnostic Laboratory (ADL). The ADL provides a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1990 on nine single cells and fifteen 3- to 360-cell modules that encompass six technologies: (Na/S, Zn/Br, Ni/Fe, Ni/Cd, Ni-metal hydride, and lead-acid). These evaluations were performed for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers an interim measure of the progress being made in battery R and D programs, a comparison of battery technologies, and a source of basic data for modelling and continuing R and D.
Constitutive modeling for isotropic materials (HOST)
NASA Technical Reports Server (NTRS)
Lindholm, U. S.; Chan, K. S.; Bodner, S. R.; Weber, R. M.; Walker, K. P.; Cassenti, B. N.
1985-01-01
This report presents the results of the second year of work on a problem which is part of the NASA HOST Program. Its goals are: (1) to develop and validate unified constitutive models for isotropic materials, and (2) to demonstrate their usefulness for structural analyses of hot section components of gas turbine engines. The unified models selected for development and evaluation are that of Bodner-Partom and Walker. For model evaluation purposes, a large constitutive data base is generated for a B1900 + Hf alloy by performing uniaxial tensile, creep, cyclic, stress relation, and thermomechanical fatigue (TMF) tests as well as biaxial (tension/torsion) tests under proportional and nonproportional loading over a wide range of strain rates and temperatures. Systematic approaches for evaluating material constants from a small subset of the data base are developed. Correlations of the uniaxial and biaxial tests data with the theories of Bodner-Partom and Walker are performed to establish the accuracy, range of applicability, and integability of the models. Both models are implemented in the MARC finite element computer code and used for TMF analyses. Benchmark notch round experiments are conducted and the results compared with finite-element analyses using the MARC code and the Walker model.
Challenges and opportunities in analysing students modelling
NASA Astrophysics Data System (ADS)
Blanco-Anaya, Paloma; Justi, Rosária; Díaz de Bustamante, Joaquín
2017-02-01
Modelling-based teaching activities have been designed and analysed from distinct theoretical perspectives. In this paper, we use one of them - the model of modelling diagram (MMD) - as an analytical tool in a regular classroom context. This paper examines the challenges that arise when the MMD is used as an analytical tool to characterise the modelling process experienced by students working in small groups aiming at creating and testing a model of a sedimentary basin from the information provided. The study was conducted in a regular Biology and Geology classroom (16-17 years old students). Data was collected through video recording of the classes, along with written reports and the material models made by each group. The results show the complexity of adapting MMD at two levels: the group modelling and the actual requirements for the activity. Our main challenges were to gather the modelling process of each individual and the group, as well as to identify, from students' speech, which stage of modelling they were performing at a given time. When facing such challenges, we propose some changes in the MMD so that it can be properly used to analyse students performing modelling activities in groups.
Harris, Joshua D; Brand, Jefferson C; Cote, Mark P; Dhawan, Aman
2017-08-01
Within the health care environment, there has been a recent and appropriate trend towards emphasizing the value of care provision. Reduced cost and higher quality improve the value of care. Quality is a challenging, heterogeneous, variably defined concept. At the core of quality is the patient's outcome, quantified by a vast assortment of subjective and objective outcome measures. There has been a recent evolution towards evidence-based medicine in health care, clearly elucidating the role of high-quality evidence across groups of patients and studies. Synthetic studies, such as systematic reviews and meta-analyses, are at the top of the evidence-based medicine hierarchy. Thus, these investigations may be the best potential source of guiding diagnostic, therapeutic, prognostic, and economic medical decision making. Systematic reviews critically appraise and synthesize the best available evidence to provide a conclusion statement (a "take-home point") in response to a specific answerable clinical question. A meta-analysis uses statistical methods to quantitatively combine data from single studies. Meta-analyses should be performed with high methodological quality homogenous studies (Level I or II) or evidence randomized studies, to minimize confounding variable bias. When it is known that the literature is inadequate or a recent systematic review has already been performed with a demonstration of insufficient data, then a new systematic review does not add anything meaningful to the literature. PROSPERO registration and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines assist authors in the design and conduct of systematic reviews and should always be used. Complete transparency of the conduct of the review permits reproducibility and improves fidelity of the conclusions. Pooling of data from overly dissimilar investigations should be avoided. This particularly applies to Level IV evidence, that is, noncomparative investigations. With proper technique, systematic reviews and meta-analyses have the potential to be powerful investigations that efficiently assist clinicians in decision making. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
Heat deposition analysis for the High Flux Isotope Reactor’s HEU and LEU core models
Davidson, Eva E.; Betzler, Benjamin R.; Chandler, David; ...
2017-08-01
The High Flux Isotope Reactor at Oak Ridge National Laboratory is an 85 MW th pressurized light-water-cooled and -moderated flux-trap type research reactor. The reactor is used to conduct numerous experiments, advancing various scientific and engineering disciplines. As part of an ongoing program sponsored by the US Department of Energy National Nuclear Security Administration Office of Material Management and Minimization, studies are being performed to assess the feasibility of converting the reactor’s highly enriched uranium fuel to low-enriched uranium fuel. To support this conversion project, reference models with representative experiment target loading and explicit fuel plate representation were developed andmore » benchmarked for both fuels to (1) allow for consistent comparison between designs for both fuel types and (2) assess the potential impact of low-enriched uranium conversion. These high-fidelity models were used to conduct heat deposition analyses at the beginning and end of the reactor cycle and are presented herein. This article (1) discusses the High Flux Isotope Reactor models developed to facilitate detailed heat deposition analyses of the reactor’s highly enriched and low-enriched uranium cores, (2) examines the computational approach for performing heat deposition analysis, which includes a discussion on the methodology for calculating the amount of energy released per fission, heating rates, power and volumetric heating rates, and (3) provides results calculated throughout various regions of the highly enriched and low-enriched uranium core at the beginning and end of the reactor cycle. These are the first detailed high-fidelity heat deposition analyses for the High Flux Isotope Reactor’s highly enriched and low-enriched core models with explicit fuel plate representation. Lastly, these analyses are used to compare heat distributions obtained for both fuel designs at the beginning and end of the reactor cycle, and they are essential for enabling comprehensive thermal hydraulics and safety analyses that require detailed estimates of the heat source within all of the reactor’s fuel element regions.« less
O'Brien, Kelly K; Tynan, Anne-Marie; Nixon, Stephanie A; Glazier, Richard H
2017-04-12
HIV is increasingly considered a chronic illness. More individuals are living longer and aging with the health-related consequences associated with HIV and multi-morbidity. Exercise is a self-management approach that can promote health for people aging with HIV. We examined the safety and effectiveness of progressive resistive exercise (PRE) interventions on immunological, virological, cardiorespiratory, strength, weight, body composition, and psychological outcomes in adults living with HIV. We conducted a systematic review using the Cochrane Collaboration protocol. Searching databases up to April 2013, we included randomized controlled trials that compared PRE with no exercise or another intervention performed at least three times per week for at least four weeks with adults living with HIV. Two reviewers independently determined study eligibility. We extracted data from included studies and assessed risk of bias using the Cochrane Collaboration risk of bias tool. Meta-analyses were conducted using random effects models with Review Manager (RevMan) computer software. Twenty studies met inclusion criteria (n = 764 participants at study completion); the majority of participants were men (77%) taking antiretroviral therapy (14/20 included studies). Exercise interventions included PRE alone (8 studies) or a combination of resistive and aerobic exercise (12 studies) ranging from 6 to 52 weeks in duration. Thirty-four meta-analyses were performed. Results demonstrated statistically significant improvements in cardiorespiratory status (maximum oxygen consumption, exercise time), strength (chest press, knee flexion), weight, and body composition (arm and thigh girth, leg muscle area) among exercisers versus non-exercisers. We found no significant differences in change in CD4 count and viral load. We were unable to perform meta-analyses for psychological outcomes however results from individual studies demonstrated improvements in health-related quality of life with exercisers compared with non-exercisers. Performing progressive resistive exercise (PRE) or a combination of resistive and aerobic exercise at least three times per week for at least six weeks is safe and can lead to improvements in cardiorespiratory fitness, strength, weight, and body composition for adults with HIV. Exercise may be considered a safe and beneficial for enhancing the health of medically stable adults aging with HIV.
Optimum Design of a Compound Helicopter
NASA Technical Reports Server (NTRS)
Yeo, Hyeonsoo; Johnson, Wayne
2006-01-01
A design and aeromechanics investigation was conducted for a 100,000-lb compound helicopter with a single main rotor, which is to cruise at 250 knots at 4000 ft/95 deg F condition. Performance, stability, and control analyses were conducted with the comprehensive rotorcraft analysis CAMRAD II. Wind tunnel test measurements of the performance of the H-34 and UH-1D rotors at high advance ratio were compared with calculations to assess the accuracy of the analysis for the design of a high speed helicopter. In general, good correlation was obtained when an increase of drag coefficients in the reverse flow region was implemented. An assessment of various design parameters (disk loading, blade loading, wing loading) on the performance of the compound helicopter was conducted. Lower wing loading (larger wing area) and higher blade loading (smaller blade chord) increased aircraft lift-to-drag ratio. However, disk loading has a small influence on aircraft lift-to-drag ratio. A rotor parametric study showed that most of the benefit of slowing the rotor occurred at the initial 20 to 30% reduction of the advancing blade tip Mach number. No stability issues were observed with the current design. Control derivatives did not change significantly with speed, but the did exhibit significant coupling.
NASA Technical Reports Server (NTRS)
Jeng, Frank F.; Lafuse, Sharon; Smith, Frederick D.; Lu, Sao-Dung; Knox, James C.; Campbell, Mellssa L.; Scull, Timothy D.; Green Steve
2010-01-01
A tool has been developed by the Sabatier Team for analyzing/optimizing CO2 removal assembly, CO2 compressor size, its operation logic, water generation from Sabatier, utilization of CO2 from crew metabolic output, and Hz from oxygen generation assembly. Tests had been conducted using CDRA/Simulation compressor set-up at MSFC in 2003. Analysis of test data has validated CO2 desorption rate profile, CO2 compressor performance, CO2 recovery and CO2 vacuum vent in CDRA desorption. Optimizing the compressor size and compressor operation logic for an integrated closed air revitalization system Is being conducted by the Sabatier Team.
Macleod, Catriona; Chiweshe, Malvern; Mavuso, Jabulile
2016-04-01
Taking a feminist health psychology approach, we conducted a systematic review of published research on abortion featured in PsycINFO over a 7-year period. We analysed the 39 articles included in the review in terms of countries in which the research was conducted, types of research, issues covered, the way the research was framed and main findings. Despite 97 per cent of abortions performed in Africa being classifiable as unsafe, there has been no engagement in knowledge production about abortion in Africa from psychologists, outside of South Africa. Given this, we outline the implications of the current knowledge base for feminism, psychology and feminist health psychology in Africa.
Gusarov, A A
2010-01-01
The author substantiates the necessity to prepare new "Rules for the organization and conduction of forensic biological examination and studies by the State Forensic Examination Boards of the Russian Federation". Their long-term absence of the reviewed document has negatively influenced the quality of work of these facilities. The structure and contents of the three previous versions of the Rules for the study of material evidence (1934, 1956, and 1996) are analysed. The structure of the new variant is designed to optimize the work of forensic medical examination bureaus and the performance of relevant studies.
Icing Test Results on an Advanced Two-Dimensional High-Lift Multi-Element Airfoil
NASA Technical Reports Server (NTRS)
Shin, Jaiwon; Wilcox, Peter; Chin, Vincent; Sheldon, David
1994-01-01
An experimental study has been conducted to investigate ice accretions on a high-lift, multi-element airfoil in the Icing Research Tunnel at the NASA Lewis Research Center. The airfoil is representative of an advanced transport wing design. The experimental work was conducted as part of a cooperative program between McDonnell Douglas Aerospace and the NASA Lewis Research Center to improve current understanding of ice accretion characteristics on the multi-element airfoil. The experimental effort also provided ice shapes for future aerodynamic tests at flight Reynolds numbers to ascertain high-lift performance effects. Ice shapes documented for a landing configuration over a variety of icing conditions are presented along with analyses.
Phylogenetic comparative methods complement discriminant function analysis in ecomorphology.
Barr, W Andrew; Scott, Robert S
2014-04-01
In ecomorphology, Discriminant Function Analysis (DFA) has been used as evidence for the presence of functional links between morphometric variables and ecological categories. Here we conduct simulations of characters containing phylogenetic signal to explore the performance of DFA under a variety of conditions. Characters were simulated using a phylogeny of extant antelope species from known habitats. Characters were modeled with no biomechanical relationship to the habitat category; the only sources of variation were body mass, phylogenetic signal, or random "noise." DFA on the discriminability of habitat categories was performed using subsets of the simulated characters, and Phylogenetic Generalized Least Squares (PGLS) was performed for each character. Analyses were repeated with randomized habitat assignments. When simulated characters lacked phylogenetic signal and/or habitat assignments were random, <5.6% of DFAs and <8.26% of PGLS analyses were significant. When characters contained phylogenetic signal and actual habitats were used, 33.27 to 45.07% of DFAs and <13.09% of PGLS analyses were significant. False Discovery Rate (FDR) corrections for multiple PGLS analyses reduced the rate of significance to <4.64%. In all cases using actual habitats and characters with phylogenetic signal, correct classification rates of DFAs exceeded random chance. In simulations involving phylogenetic signal in both predictor variables and predicted categories, PGLS with FDR was rarely significant, while DFA often was. In short, DFA offered no indication that differences between categories might be explained by phylogenetic signal, while PGLS did. As such, PGLS provides a valuable tool for testing the functional hypotheses at the heart of ecomorphology. Copyright © 2013 Wiley Periodicals, Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Milani, Gabriele, E-mail: milani@stru.polimi.it; Valente, Marco, E-mail: milani@stru.polimi.it
2014-10-06
This study presents some results of a comprehensive numerical analysis on three masonry churches damaged by the recent Emilia-Romagna (Italy) seismic events occurred in May 2012. The numerical study comprises: (a) pushover analyses conducted with a commercial code, standard nonlinear material models and two different horizontal load distributions; (b) FE kinematic limit analyses performed using a non-commercial software based on a preliminary homogenization of the masonry materials and a subsequent limit analysis with triangular elements and interfaces; (c) kinematic limit analyses conducted in agreement with the Italian code and based on the a-priori assumption of preassigned failure mechanisms, where themore » masonry material is considered unable to withstand tensile stresses. All models are capable of giving information on the active failure mechanism and the base shear at failure, which, if properly made non-dimensional with the weight of the structure, gives also an indication of the horizontal peak ground acceleration causing the collapse of the church. The results obtained from all three models indicate that the collapse is usually due to the activation of partial mechanisms (apse, façade, lateral walls, etc.). Moreover the horizontal peak ground acceleration associated to the collapse is largely lower than that required in that seismic zone by the Italian code for ordinary buildings. These outcomes highlight that structural upgrading interventions would be extremely beneficial for the considerable reduction of the seismic vulnerability of such kind of historical structures.« less
Heat transport through atomic contacts.
Mosso, Nico; Drechsler, Ute; Menges, Fabian; Nirmalraj, Peter; Karg, Siegfried; Riel, Heike; Gotsmann, Bernd
2017-05-01
Heat transport and dissipation at the nanoscale severely limit the scaling of high-performance electronic devices and circuits. Metallic atomic junctions serve as model systems to probe electrical and thermal transport down to the atomic level as well as quantum effects that occur in one-dimensional (1D) systems. Whereas charge transport in atomic junctions has been studied intensively in the past two decades, heat transport remains poorly characterized because it requires the combination of a high sensitivity to small heat fluxes and the formation of stable atomic contacts. Here we report heat-transfer measurements through atomic junctions and analyse the thermal conductance of single-atom gold contacts at room temperature. Simultaneous measurements of charge and heat transport reveal the proportionality of electrical and thermal conductance, quantized with the respective conductance quanta. This constitutes a verification of the Wiedemann-Franz law at the atomic scale.
Study of temperature dependent electrical properties of Se80-xTe20Bix (x = 0, 3, 6) glasses
NASA Astrophysics Data System (ADS)
Deepika, Singh, Hukum
2018-05-01
This paper reports the variation in electrical properties of Se80-xTe20Bix (x = 0, 3, 6) glasses studied at different temperatures. The amorphous samples were prepared using the melt quenching method and the electrical measurements were performed on Keithley Electrometer in the temperature ranging from 298-373 K. The I-V characteristics were noted at different temperatures and the data obtained was analysed to get dc electrical conductivity and activation energy of electrical conduction. Further, Mott's 3D VRH model has been applied to obtain density of states, hopping range and hopping energy at different temperatures. The obtained results show that dc electrical conductivity increases with increase in Bi composition in Se-Te system. These compositions also show close agreement to Mott's VRH model.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simbeck, D.J.
1993-12-31
Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected August 14 from Poplar Creek Miles 6.0 and 4.3 was conducted from August 24--September 2, 1993. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments. Attachments to this report include: Chain of custody form -- original;more » Toxicity test bench sheets and statistical analyses; and Ammonia analysis request and results.« less
ANALYSES OF RESPONSE–STIMULUS SEQUENCES IN DESCRIPTIVE OBSERVATIONS
Samaha, Andrew L; Vollmer, Timothy R; Borrero, Carrie; Sloman, Kimberly; Pipkin, Claire St. Peter; Bourret, Jason
2009-01-01
Descriptive observations were conducted to record problem behavior displayed by participants and to record antecedents and consequences delivered by caregivers. Next, functional analyses were conducted to identify reinforcers for problem behavior. Then, using data from the descriptive observations, lag-sequential analyses were conducted to examine changes in the probability of environmental events across time in relation to occurrences of problem behavior. The results of the lag-sequential analyses were interpreted in light of the results of functional analyses. Results suggested that events identified as reinforcers in a functional analysis followed behavior in idiosyncratic ways: after a range of delays and frequencies. Thus, it is possible that naturally occurring reinforcement contingencies are arranged in ways different from those typically evaluated in applied research. Further, these complex response–stimulus relations can be represented by lag-sequential analyses. However, limitations to the lag-sequential analysis are evident. PMID:19949537
The Needs Analysis in Self-Concept Module Development
ERIC Educational Resources Information Center
Yusop, Yusni Mohamad; Sumari, Melati; Mohamed, Fatanah; Said, Shahriza; Azeez, Mohd Ibrahim K.; Jamil, Mohd Ridhuan Mohd
2015-01-01
This research studies needs analyses conducted to examine the need for a self-concept module. Two types of analyses had been conducted; content analysis and experts' consensus. Content analysis was conducted to explore the issues of self-concept from the theory and literature perspective. Later, needs analysis had also been carried out to observe…
LOD score exclusion analyses for candidate genes using random population samples.
Deng, H W; Li, J; Recker, R R
2001-05-01
While extensive analyses have been conducted to test for, no formal analyses have been conducted to test against, the importance of candidate genes with random population samples. We develop a LOD score approach for exclusion analyses of candidate genes with random population samples. Under this approach, specific genetic effects and inheritance models at candidate genes can be analysed and if a LOD score is < or = - 2.0, the locus can be excluded from having an effect larger than that specified. Computer simulations show that, with sample sizes often employed in association studies, this approach has high power to exclude a gene from having moderate genetic effects. In contrast to regular association analyses, population admixture will not affect the robustness of our analyses; in fact, it renders our analyses more conservative and thus any significant exclusion result is robust. Our exclusion analysis complements association analysis for candidate genes in random population samples and is parallel to the exclusion mapping analyses that may be conducted in linkage analyses with pedigrees or relative pairs. The usefulness of the approach is demonstrated by an application to test the importance of vitamin D receptor and estrogen receptor genes underlying the differential risk to osteoporotic fractures.
NASA Astrophysics Data System (ADS)
Hafner, J.; Uckert, G.; Graef, F.; Hoffmann, H.; Kimaro, A. A.; Sererya, O.; Sieber, S.
2018-02-01
In Tanzania, a majority of rural residents cook using firewood-based three-stone-fire stoves. In this study, quantitative performance differences between technologically advanced improved cooking stoves and three-stone-fire stoves are analysed. We test the performance of improved cooking stoves and three-stone-fire stoves using local cooks, foods, and fuels, in the semi-arid region of Dodoma in Tanzania. We used the cooking protocol of the Controlled Cooking Test following a two-pot test design. The findings of the study suggest that improved cooking stoves use less firewood and less time than three-stone-fire stoves to conduct a predefined cooking task. In total, 40 households were assessed and ask to complete two different cooking tasks: (1) a fast cooking meal (rice and vegetables) and (2) a slow cooking meal (beans and rice). For cooking task 1, the results show a significant reduction in firewood consumption of 37.1% by improved cooking stoves compared to traditional three-stone-fire stoves; for cooking task 2 a reduction of 15.6% is found. In addition, it was found that the time needed to conduct cooking tasks 1 and 2 was significantly reduced by 26.8% and 22.8% respectively, when improved cooking stoves were used instead of three-stone-fire-stoves. We observed that the villagers altered the initial improved cooking stove design, resulting in the so-called modified improved cooking stove. In an additional Controlled Cooking Test, we conducted cooking task 3: a very fast cooking meal (maize flour and vegetables) within 32 households. Significant changes between the initial and modified improved cooking stoves regarding firewood and time consumption were not detected. However, analyses show that both firewood and time consumption during cooking was reduced when large amounts (for 6-7 household members) of food were prepared instead of small amounts (for 2-3 household members).
Xu, X.-H.; Xiong, D.-H.; Liu, X.-G.; Guo, Y.; Chen, Y.; Zhao, J.; Recker, R. R.; Deng, H.-W.
2010-01-01
Summary This study was conducted to test whether there exists an association between vitamin D-binding protein (DBP) gene and compression strength index (CSI) phenotype. Candidate gene association analyses were conducted in total sample, male subgroup, and female subgroup, respectively. Two single-nucleotide polymorphisms (SNPs) with significant association results were found in males, suggesting the importance of DBP gene polymorphisms on the variation in CSI especially in Caucasian males. Introduction CSI of the femoral neck (FN) is a newly developed phenotype integrating information about bone size, body size, and bone mineral density. It is considered to have the potential to improve the performance of risk assessment for hip fractures because it is based on a combination of phenotypic traits influencing hip fractures rather than a single trait. CSI is under moderate genetic determination (with a heritability of ~44% found in this study), but the relevant genetic study is still rather scarce. Methods Based on the known physiological role of DBP in bone biology and the relatively high heritability of CSI, we tested 12 SNPs of the DBP gene for association with CSI variation in 405 Caucasian nuclear families comprising 1,873 subjects from the Midwestern US. Association analyses were performed in the total sample, male and female subgroups, respectively. Results Significant associations with CSI were found with two SNPs (rs222029, P=0.0019; rs222020, P=0.0042) for the male subgroup. Haplotype-based association tests corroborated the single-SNP results. Conclusions Our findings suggest that the DBP gene might be one of the genetic factors influencing CSI phenotype in Caucasians, especially in males. PMID:19543766
Seismic response and damage detection analyses of an instrumented steel moment-framed building
Rodgers, J.E.; Celebi, M.
2006-01-01
The seismic performance of steel moment-framed buildings has been of particular interest since brittle fractures were discovered at the beam-column connections in a number of buildings following the M 6.7 Northridge earthquake of January 17, 1994. A case study of the seismic behavior of an extensively instrumented 13-story steel moment frame building located in the greater Los Angeles area of California is described herein. Response studies using frequency domain, joint time-frequency, system identification, and simple damage detection analyses are performed using an extensive strong motion dataset dating from 1971 to the present, supported by engineering drawings and results of postearthquake inspections. These studies show that the building's response is more complex than would be expected from its highly symmetrical geometry. The response is characterized by low damping in the fundamental mode, larger accelerations in the middle and lower stories than at the roof and base, extended periods of vibration after the cessation of strong input shaking, beating in the response, elliptical particle motion, and significant torsion during strong shaking at the top of the concrete piers which extend from the basement to the second floor. The analyses conducted indicate that the response of the structure was elastic in all recorded earthquakes to date, including Northridge. Also, several simple damage detection methods employed did not indicate any structural damage or connection fractures. The combination of a large, real structure and low instrumentation density precluded the application of many recently proposed advanced damage detection methods in this case study. Overall, however, the findings of this study are consistent with the limited code-compliant postearthquake intrusive inspections conducted after the Northridge earthquake, which found no connection fractures or other structural damage. ?? ASCE.
Chiastra, Claudio; Wu, Wei; Dickerhoff, Benjamin; Aleiou, Ali; Dubini, Gabriele; Otake, Hiromasa; Migliavacca, Francesco; LaDisa, John F
2016-07-26
The optimal stenting technique for coronary artery bifurcations is still debated. With additional advances computational simulations can soon be used to compare stent designs or strategies based on verified structural and hemodynamics results in order to identify the optimal solution for each individual's anatomy. In this study, patient-specific simulations of stent deployment were performed for 2 cases to replicate the complete procedure conducted by interventional cardiologists. Subsequent computational fluid dynamics (CFD) analyses were conducted to quantify hemodynamic quantities linked to restenosis. Patient-specific pre-operative models of coronary bifurcations were reconstructed from CT angiography and optical coherence tomography (OCT). Plaque location and composition were estimated from OCT and assigned to models, and structural simulations were performed in Abaqus. Artery geometries after virtual stent expansion of Xience Prime or Nobori stents created in SolidWorks were compared to post-operative geometry from OCT and CT before being extracted and used for CFD simulations in SimVascular. Inflow boundary conditions based on body surface area, and downstream vascular resistances and capacitances were applied at branches to mimic physiology. Artery geometries obtained after virtual expansion were in good agreement with those reconstructed from patient images. Quantitative comparison of the distance between reconstructed and post-stent geometries revealed a maximum difference in area of 20.4%. Adverse indices of wall shear stress were more pronounced for thicker Nobori stents in both patients. These findings verify structural analyses of stent expansion, introduce a workflow to combine software packages for solid and fluid mechanics analysis, and underscore important stent design features from prior idealized studies. The proposed approach may ultimately be useful in determining an optimal choice of stent and position for each patient. Copyright © 2015 Elsevier Ltd. All rights reserved.
Predicting the reading skill of Japanese children.
Ogino, Tatsuya; Hanafusa, Kaoru; Morooka, Teruko; Takeuchi, Akihito; Oka, Makio; Ohtsuka, Yoko
2017-02-01
To clarify cognitive processes underlining the development of reading in children speaking Japanese as their first language, we examined relationships between performances of cognitive tasks in the preschool period and later reading abilities. Ninety-one normally developing preschoolers (41 girls and 50 boys; 5years 4months to 6years 4months, mean 5years 10months) participated as subjects. We conducted seven cognitive tasks including phonological awareness tasks, naming tasks, and working memory tasks in the preschool period. In terms of reading tasks, the hiragana naming task was administered in the preschool period; the reading times, which is a composite score of the monomoraic syllable reading task, the word and the non-word reading tasks, and the single sentence reading task, was evaluated in first and second grade; and the kanji reading task (naming task) was tested in second grade. Raven's colored progressive matrices and picture vocabulary test revised were also conducted in first grade. Correlation analyses between task scores and stepwise multiple regression analyses were implemented. Tasks tapping phonological awareness, lexical access, and verbal working memory showed significant correlations with reading tasks. In the multiple regression analyses the performances in the verbal working memory task played a key role in predicting character naming task scores (the hiragana naming task and the kanji reading task) while the digit naming task was an important predictor of reading times. Unexpectedly, the role of phonological (mora) awareness was modest among children speaking Japanese. Cognitive functions including phonological awareness, digit naming, and verbal working memory (especially the latter two) were involved in the development of reading skills of children speaking Japanese. Copyright © 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Thermophysical parameters from laboratory measurements and tests in borehole heat exchangers
NASA Astrophysics Data System (ADS)
Pacetti, Chiara; Giuli, Gabriele; Invernizzi, Chiara; Chiozzi, Paolo; Verdoya, Massimo
2017-04-01
Besides the type of thermal regime, the performance of borehole heat exchangers relies on the overall thermal resistance of the borehole. This parameter strongly depends on the underground thermal conductivity, which accounts for most of the heat that can be extracted. The geometric configuration and the increase of thermal conductivity of the grout filling back the bore can yield a non-negligible enhancement in thermal performances. In this paper, we present a study on a pilot geothermal plant consisting of two borehole heat exchangers, 95 m deep and 9 m apart. Laboratory and in situ tests were carried out with the aim of investigating underground thermal properties, mechanisms of heat transfer and thermal characteristics of the filling grouts. Samples of grouting materials were analysed in the lab for assessing the thermal conductivity. An attempt to improve the thermal conductivity was made by doping grouts with alumina. Results showed that alumina large concentrations can increase the thermal conductivity by 25-30%. The in situ experiments included thermal logs under conditions of thermal equilibrium and thermal response tests (TRTs). The analysis of the temperature-depth profiles, based on the mass and energy balance in permeable horizons with uniform thermo-hydraulic and steady-state conditions, revealed that the underground thermal regime is dominated by conduction. TRTs were performed by injecting a constant heat rate per unit length into the boreholes for 60-90 hours. After TRTs, the temperature drop off (TDO) was recorded at 20-m-depth intervals for one week in both holes. The TRT time series were interpreted according to the classical model of the infinite line source (ILS), to infer the underground thermal conductivity. The TDO records allowed the inference of the underground thermal properties variation with depth. The results of thermal conductivity inferred with the ILS method are consistent with the values obtained from the TDO analysis.
Wu, Wei-Sheng; Jhou, Meng-Jhun
2017-01-13
Missing value imputation is important for microarray data analyses because microarray data with missing values would significantly degrade the performance of the downstream analyses. Although many microarray missing value imputation algorithms have been developed, an objective and comprehensive performance comparison framework is still lacking. To solve this problem, we previously proposed a framework which can perform a comprehensive performance comparison of different existing algorithms. Also the performance of a new algorithm can be evaluated by our performance comparison framework. However, constructing our framework is not an easy task for the interested researchers. To save researchers' time and efforts, here we present an easy-to-use web tool named MVIAeval (Missing Value Imputation Algorithm evaluator) which implements our performance comparison framework. MVIAeval provides a user-friendly interface allowing users to upload the R code of their new algorithm and select (i) the test datasets among 20 benchmark microarray (time series and non-time series) datasets, (ii) the compared algorithms among 12 existing algorithms, (iii) the performance indices from three existing ones, (iv) the comprehensive performance scores from two possible choices, and (v) the number of simulation runs. The comprehensive performance comparison results are then generated and shown as both figures and tables. MVIAeval is a useful tool for researchers to easily conduct a comprehensive and objective performance evaluation of their newly developed missing value imputation algorithm for microarray data or any data which can be represented as a matrix form (e.g. NGS data or proteomics data). Thus, MVIAeval will greatly expedite the progress in the research of missing value imputation algorithms.
Features of Computer-Based Decision Aids: Systematic Review, Thematic Synthesis, and Meta-Analyses
Krömker, Dörthe; Meguerditchian, Ari N; Tamblyn, Robyn
2016-01-01
Background Patient information and education, such as decision aids, are gradually moving toward online, computer-based environments. Considerable research has been conducted to guide content and presentation of decision aids. However, given the relatively new shift to computer-based support, little attention has been given to how multimedia and interactivity can improve upon paper-based decision aids. Objective The first objective of this review was to summarize published literature into a proposed classification of features that have been integrated into computer-based decision aids. Building on this classification, the second objective was to assess whether integration of specific features was associated with higher-quality decision making. Methods Relevant studies were located by searching MEDLINE, Embase, CINAHL, and CENTRAL databases. The review identified studies that evaluated computer-based decision aids for adults faced with preference-sensitive medical decisions and reported quality of decision-making outcomes. A thematic synthesis was conducted to develop the classification of features. Subsequently, meta-analyses were conducted based on standardized mean differences (SMD) from randomized controlled trials (RCTs) that reported knowledge or decisional conflict. Further subgroup analyses compared pooled SMDs for decision aids that incorporated a specific feature to other computer-based decision aids that did not incorporate the feature, to assess whether specific features improved quality of decision making. Results Of 3541 unique publications, 58 studies met the target criteria and were included in the thematic synthesis. The synthesis identified six features: content control, tailoring, patient narratives, explicit values clarification, feedback, and social support. A subset of 26 RCTs from the thematic synthesis was used to conduct the meta-analyses. As expected, computer-based decision aids performed better than usual care or alternative aids; however, some features performed better than others. Integration of content control improved quality of decision making (SMD 0.59 vs 0.23 for knowledge; SMD 0.39 vs 0.29 for decisional conflict). In contrast, tailoring reduced quality of decision making (SMD 0.40 vs 0.71 for knowledge; SMD 0.25 vs 0.52 for decisional conflict). Similarly, patient narratives also reduced quality of decision making (SMD 0.43 vs 0.65 for knowledge; SMD 0.17 vs 0.46 for decisional conflict). Results were varied for different types of explicit values clarification, feedback, and social support. Conclusions Integration of media rich or interactive features into computer-based decision aids can improve quality of preference-sensitive decision making. However, this is an emerging field with limited evidence to guide use. The systematic review and thematic synthesis identified features that have been integrated into available computer-based decision aids, in an effort to facilitate reporting of these features and to promote integration of such features into decision aids. The meta-analyses and associated subgroup analyses provide preliminary evidence to support integration of specific features into future decision aids. Further research can focus on clarifying independent contributions of specific features through experimental designs and refining the designs of features to improve effectiveness. PMID:26813512
Is cognitive adaptation training (CAT) compensatory, restorative, or both?
Fredrick, Megan M; Mintz, Jim; Roberts, David L; Maples, Natalie J; Sarkar, Sonali; Li, Xueying; Velligan, Dawn I
2015-08-01
Cognitive adaptation training (CAT) is a psychosocial treatment incorporating environmental supports including signs, checklists to bypass the cognitive deficits of schizophrenia. Our objective was to examine the association between CAT, functional outcomes, and cognitive test performance (cognition). The two research questions were as follows: 1) Does cognition mediate the effect of CAT intervention on functional outcome? 2) Does CAT impact cognitive test performance? A total of 120 participants with schizophrenia were randomized to one of three treatments: 1) CAT (weekly for 9months; monthly thereafter), 2) generic environmental supports (given to participants on clinic visits to promote adaptive behavior), or 3) treatment as usual (TAU). Assessments of cognition and functional outcome were conducted at baseline, 9 and 24months. Mediation analyses and mixed effects regression were conducted. Mediation analyses revealed that during the initial 9months, the direct path from treatment group to functional outcome on the primary measure was positive and highly significant. CAT significantly improved functional outcome compared to the other treatments. However, paths involving cognition were negligible. There was no evidence that cognition mediated improvement in functional outcomes. At 24months, cognition improved more in CAT compared to other treatment groups. The test for cognition mediating improvement in functional outcomes was not significant at this time point. However, improvement in functional outcome led to better performance on cognitive testing. We concluded that improvement in cognition is not a necessary condition for improvement in functional outcome and that greater engagement in functional behavior has a positive impact on cognition. Copyright © 2015 Elsevier B.V. All rights reserved.
Volumetric neuroimage analysis extensions for the MIPAV software package.
Bazin, Pierre-Louis; Cuzzocreo, Jennifer L; Yassa, Michael A; Gandler, William; McAuliffe, Matthew J; Bassett, Susan S; Pham, Dzung L
2007-09-15
We describe a new collection of publicly available software tools for performing quantitative neuroimage analysis. The tools perform semi-automatic brain extraction, tissue classification, Talairach alignment, and atlas-based measurements within a user-friendly graphical environment. They are implemented as plug-ins for MIPAV, a freely available medical image processing software package from the National Institutes of Health. Because the plug-ins and MIPAV are implemented in Java, both can be utilized on nearly any operating system platform. In addition to the software plug-ins, we have also released a digital version of the Talairach atlas that can be used to perform regional volumetric analyses. Several studies are conducted applying the new tools to simulated and real neuroimaging data sets.
Data Availability in Appliance Standards and Labeling Program Development and Evaluation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Romankiewicz, John; Khanna, Nina; Vine, Edward
2013-05-01
In this report, we describe the necessary data inputs for both standards development and program evaluation and perform an initial assessment of the availability and uncertainty of those data inputs in China. For standards development, we find that China and its standards and labeling program administrators currently has access to the basic market and technical data needed for conducting market and technology assessment and technological and economic analyses. Some data, such as shipments data, is readily available from the China Energy Label product registration database while the availability of other data, including average unit energy consumption, prices and design options,more » needs improvement. Unlike some other countries such as the United States, most of the necessary data for conducting standards development analyses are not publicly available or compiled in a consolidated data source. In addition, improved data on design and efficiency options as well as cost data (e.g., manufacturing costs, mark-ups, production and product use-phase costs) – key inputs to several technoeconomic analyses – are particularly in need given China’s unconsolidated manufacturing industry. For program evaluation, we find that while China can conduct simple savings evaluations on its incentive programs with the data it currently has available from the Ministry of Finance – the program administrator, the savings estimates produced by such an evaluation will carry high uncertainty. As such, China could benefit from an increase in surveying and metering in the next one to three years to decrease the uncertainty surrounding key data points such as unit energy savings and free ridership.« less
NASA-UVA light aerospace alloy and structures technology program
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Stoner, Glenn E.; Swanson, Robert E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.
1990-01-01
The objective of the Light Aerospace Alloy and Structures Technology Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and associated thermal gradient structures. Individual technical objectives are established for each project. Efforts aim to produce basic understanding of material behavior, monolithic and composite alloys, processing methods, solid and mechanics analyses, measurement advances, and a pool of educated graduate students. Progress is reported for 11 areas of study.
2000-06-01
completed over AOC 57 at the former Fort Devens in Ayer, MA. Geophysical work was conducted in two...data generated from chemical analyses performed on soil samples collected during the 1995 AOC 57 , 63AX, and 69W Remedial Investigations at Fort Devens ...pg/g W0059621.T80/1 9144-03 continued TABLE D-1 SUMMARY OF ANALYTICAL PARAMETERS AOC 57 , 63AX, AND 69W REMEDIAL INVESTIGATION FORT DEVENS
Attention-training with children from socioeconomically disadvantaged backgrounds in Cape Town.
Schrieff-Elson, Leigh E; Ockhuizen, Ju-Reyn H; During, Genevieve; Thomas, Kevin G F
2017-09-01
Attention is a core process underlying competence in higher-order cognitive abilities. Previous research suggests that healthy children from low socioeconomic status (SES) backgrounds perform poorly, relative to those from higher SES backgrounds, on tasks assessing attentional abilities. In this pilot study, we investigated the effects of an attention-training intervention on task performance in low-SES children. We conducted a quasi-controlled trial with stratified randomisation, using a pre-test/ post-test design. Participants were low-SES children aged 7-13 years. Each was assigned to either an intervention group, a play control group, or a test-only control group (n = 5 per group). We implemented a ten-week manualised cognitive rehabilitation program, Pay Attention!, administering standardised tests of attention, working memory, and inhibition before and after the intervention. Between- and within-group analyses and Reliable Change Index statistics evaluated differences in scores from pre- to post-intervention. Analyses detected no notable between-group differences at either pre- or post-intervention testing. However, on tests of selective attention, attentional control, and inhibition, there were significant within-group and positive individual reliable changes exclusive to the intervention-group participants. Given the variability in our findings, more research needs be conducted with a larger sample to determine, with greater rigour, the efficacy of the intervention within samples of healthy children from low-SES backgrounds.
Fach, S; Dierkes, C
2011-01-01
The focus in this work was on subsoil infiltration of stormwater from parking lots. With regard to operation, reduced infiltration performance due to clogging and pollutants in seepage, which may contribute to contaminate groundwater, are of interest. The experimental investigation covered a pervious pavement with a subjacent infiltration trench draining an impervious area of 2 ha. In order to consider seasonal effects on the infiltration performance, the hydraulic conductivity was measured tri-monthly during monitoring with a mobile sprinkling unit. To assess natural deposits jointing, road bed, gravel of infiltration trenches and subsoil were analysed prior to commencement of monitoring for heavy metals, polycyclic aromatic and mineral oil type hydrocarbons. Furthermore, from 22 storm events, water samples of rainfall, surface runoff, seepage and ground water were analysed with regard to the above mentioned pollutants. The study showed that the material used for the joints had a major impact on the initial as well as the final infiltration rates. Due to its poor hydraulic conductivity, limestone gravel should not be used as jointing. Furthermore, it is recommended that materials for the infiltration facilities are ensured free of any contaminants prior to construction. Polycyclic aromatic and mineral oil type hydrocarbons were, with the exception of surface runoff, below detection limits. Heavy metal concentrations of groundwater were with the exception of lead (because of high background concentrations), below the permissible limits.
Large eddy simulation and direct numerical simulation of high speed turbulent reacting flows
NASA Technical Reports Server (NTRS)
Adumitroaie, V.; Frankel, S. H.; Madnia, C. K.; Givi, P.
1993-01-01
The objective of this research is to make use of Large Eddy Simulation (LES) and Direct Numerical Simulation (DNS) for the computational analyses of high speed reacting flows. Our efforts in the first phase of this research conducted within the past three years have been directed in several issues pertaining to intricate physics of turbulent reacting flows. In our previous 5 semi-annual reports submitted to NASA LaRC, as well as several technical papers in archival journals, the results of our investigations have been fully described. In this progress report which is different in format as compared to our previous documents, we focus only on the issue of LES. The reason for doing so is that LES is the primary issue of interest to our Technical Monitor and that our other findings were needed to support the activities conducted under this prime issue. The outcomes of our related investigations, nevertheless, are included in the appendices accompanying this report. The relevance of the materials in these appendices are, therefore, discussed only briefly within the body of the report. Here, results are presented of a priori and a posterior analyses for validity assessments of assumed Probability Density Function (PDF) methods as potential subgrid scale (SGS) closures for LES of turbulent reacting flows. Simple non-premixed reacting systems involving an isothermal reaction of the type A + B yields Products under both chemical equilibrium and non-equilibrium conditions are considered. A priori analyses are conducted of a homogeneous box flow, and a spatially developing planar mixing layer to investigate the performance of the Pearson Family of PDF's as SGS models. A posteriori analyses are conducted of the mixing layer using a hybrid one-equation Smagorinsky/PDF SGS closure. The Smagorinsky closure augmented by the solution of the subgrid turbulent kinetic energy (TKE) equation is employed to account for hydrodynamic fluctuations, and the PDF is employed for modeling the effects of scalar fluctuations. The implementation of the model requires the knowledge of the local values of the first two SGS moments. These are provided by additional modeled transport equations. In both a priori and a posteriori analyses, the predicted results are appraised by comparison with subgrid averaged results generated by DNS. Based on these results, the paths to be followed in future investigations are identified.
Lightning Effects in the Payload Changeout Room
NASA Technical Reports Server (NTRS)
Thomas, Garland L.; Fisher, Franklin A.; Collier, Richard S.; Medelius, Pedro J.
1997-01-01
Analytical and empirical studies have been performed to provide better understanding of the electromagnetic environment inside the Payload Changeout Room and Orbiter payload bay resulting from lightning strikes to the launch pad lightning protection system. The analytical studies consisted of physical and mathematical modeling of the pad structure and the Payload Changeout Room. Empirical testing was performed using a lightning simulator to simulate controlled (8 kA) lightning strikes to the catenary wire lightning protection system. In addition to the analyses and testing listed above, an analysis of the configuration with the vehicle present was conducted, in lieu of testing, by the Finite Difference, Time Domain method.
NASA Technical Reports Server (NTRS)
1972-01-01
The results are reported of additional studies which were conducted to supplement conclusions drawn in the MSC Mission Report and analyses which were not completed in time to meet the Mission Report dealine. A detailed evaluation of the Abort Guidance System sensor assembly and results from the investigation of the X gyro loop anomaly are included. Further evidence is presented substantiating the excellent LM IMU performance obtained from preliminary indications. A detailed study is presented of the procedural changes implemented on Apollo 16 to diminish the number and duration of interruptions to the CSM DAP attitude maneuver during P20 Option 5 operations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
French, Sean B.; Stauffer, Philip H.; Birdsell, Kay H.
As a condition to the disposal authorization statement issued to Los Alamos National Laboratory (LANL or the Laboratory) on March 17, 2010, a comprehensive performance assessment and composite analysis maintenance program must be implemented for the Technical Area 54, Area G disposal facility. Annual determinations of the adequacy of the performance assessment and composite analysis (PA/CA) are to be conducted under the maintenance program to ensure that the conclusions reached by those analyses continue to be valid. This report summarizes the results of the fiscal year (FY) 2015 annual review for Area G.
Low lattice thermal conductivity and good thermoelectric performance of cinnabar
NASA Astrophysics Data System (ADS)
Zhao, Yinchang; Dai, Zhenhong; Lian, Chao; Zeng, Shuming; Li, Geng; Ni, Jun; Meng, Sheng
2017-11-01
Based on the combination of first-principles calculations, Boltzmann transport equation, and electron-phonon interaction (EPI), we investigate the thermal and electronic transport properties of crystalline cinnabar (α -HgS ). The calculated lattice thermal conductivity κL is remarkably low, e.g., 0.60 Wm-1K-1 at 300 K , which is about 30 % of the value for the typical thermoelectric material PbTe. Via taking fully into account the k dependence of the electron relaxation time computed from the EPI matrix, the accurate numerical results of thermopower S , electrical conductivity σ , and electronic thermal conductivity κE are obtained. The calculated power factor S2σ is relatively high while the value of κE is negligible, which, together with the fairly low κL, leads to a good thermoelectric performance in the n -type doped α -HgS , with the figure of merit z T even exceeding 1.4. Our analyses reveal that (i) the large weighted phase space and the quite low phonon group velocity result in the low κL, (ii) the presence of flat band around the Fermi level combined with the large band gap causes the high S , and (iii) the small electron linewidths of the conduction band lead to a large relaxation time and thus a relatively high σ . These results support that α -HgS is a potential candidate for thermoelectric applications.
Structural Fluctuation and Thermophysical Properties of Molten II-VI Compounds
NASA Technical Reports Server (NTRS)
2003-01-01
The objectives of the project is to conduct ground-based experimental and theoretical research on the structural fluctuations and thermophysical properties of molten II-VI compounds to enhance the basic understanding of the existing flight experiments in microgravity materials science programs and to study the fundamental heterophase fluctuations phenomena in these melts by: 1) Conducting neutron scattering analysis and measuring quantitatively the relevant thermophysical properties of the II-VI melts such as viscosity, electrical conductivity, thermal diffusivity and density as well as the relaxation characteristics of these properties to advance the understanding of the structural properties and the relaxation phenomena in these melts and 2) Performing theoretical analyses on the melt systems to interpret the experimental results. All the facilities required for the experimental measurements have been procured, installed and tested. A relaxation phenomenon, which shows a slow drift of the measured thermal conductivity toward the equilibrium value after cooling of the sample, was observed for the first time. An apparatus based on the transient torque induced by a rotating magnetic field has been developed to determine the viscosity and electrical conductivity of semiconducting liquids. Viscosity measurements on molten tellurium showed similar relaxation behavior as the measured diffusivity. Neutron scattering experiments were performed on the HgTe and HgZnTe melts and the results on pair distribution showed better resolution than previous reported.
Space-based solar power conversion and delivery systems study. Volume 2: Engineering analysis
NASA Technical Reports Server (NTRS)
1977-01-01
The technical and economic feasibility of Satellite Solar Power Systems was studied with emphasis on the analysis and definition of an integrated strawman configuration concept, from which credible cost data could be estimated. Specifically, system concepts for each of the major subprogram areas were formulated, analyzed, and iterated to the degree necessary for establishing an overall, workable baseline system design. Cost data were estimated for the baseline and used to conduct economic analyses. The baseline concept selected was a 5-GW crystal silicon truss-type photovoltaic configuration, which represented the most mature concept available. The overall results and major findings, and the results of technical analyses performed during the final phase of the study efforts are reported.
Web-Based Integrated Research Environment for Aerodynamic Analyses and Design
NASA Astrophysics Data System (ADS)
Ahn, Jae Wan; Kim, Jin-Ho; Kim, Chongam; Cho, Jung-Hyun; Hur, Cinyoung; Kim, Yoonhee; Kang, Sang-Hyun; Kim, Byungsoo; Moon, Jong Bae; Cho, Kum Won
e-AIRS[1,2], an abbreviation of ‘e-Science Aerospace Integrated Research System,' is a virtual organization designed to support aerodynamic flow analyses in aerospace engineering using the e-Science environment. As the first step toward a virtual aerospace engineering organization, e-AIRS intends to give a full support of aerodynamic research process. Currently, e-AIRS can handle both the computational and experimental aerodynamic research on the e-Science infrastructure. In detail, users can conduct a full CFD (Computational Fluid Dynamics) research process, request wind tunnel experiment, perform comparative analysis between computational prediction and experimental measurement, and finally, collaborate with other researchers using the web portal. The present paper describes those services and the internal architecture of the e-AIRS system.
Spaceflight-induced Bone Loss: Is there a Risk for Accelerated Osteoporosis after Return?
NASA Technical Reports Server (NTRS)
Sibonga, Jean
2008-01-01
The evidence-to to-date suggests that the rapid rate of site-specific bone loss in space, due to the unbalanced stimulation of bone resorption, may predispose crew members to irreversible changes in bone structure and microarchitecture. No analyses conducted in the postflight period to assess microarchitectural changes. There is no complete analysis of skeletal recovery in the postflight period to evaluate the structural changes that accompany increases in DXA aBMD. Postflight analyses based upon QCT scans performed on limited crew members indicate reductions in hip bone strength and incomplete recovery at 1 year. No recovery of trabecular vBMD after 1 year return (HRP IWG). Time course of bone loss in space unknown.
The art and science of rotary wing data correlation
NASA Technical Reports Server (NTRS)
Drees, J. M.
1976-01-01
This paper presents an overview of the correlation of helicopter rotor performance and loads data from various tests and analyses. Information is included from U.S. Army-sponsored tests conducted by Bell Helicopter Company for free-flight full-scale tests in the NASA-Ames 40 x 80 wind tunnel, one-fifth scale tests in the NASA-Langley Transonic Dynamics Tunnel, and small-scale tests of a rotor in air. These test data are compared with each other, where appropriate, and with calculated results. Typical examples illustrate the state of the art for correlation and indicate anomalies encountered. It is concluded that a procedure using theoretical analyses to aid in interpretation and evaluation of test results is essential to developing a science of correlation.
Analysis of the STS-126 Flow Control Valve Structural-Acoustic Coupling Failure
NASA Technical Reports Server (NTRS)
Jones, Trevor M.; Larko, Jeffrey M.; McNelis, Mark E.
2010-01-01
During the Space Transportation System mission STS-126, one of the main engine's flow control valves incurred an unexpected failure. A section of the valve broke off during liftoff. It is theorized that an acoustic mode of the flowing fuel, coupled with a structural mode of the valve, causing a high cycle fatigue failure. This report documents the analysis efforts conducted in an attempt to verify this theory. Hand calculations, computational fluid dynamics, and finite element methods are all implemented and analyses are performed using steady-state methods in addition to transient analysis methods. The conclusion of the analyses is that there is a critical acoustic mode that aligns with a structural mode of the valve
Thermal Impact of Fasteners in High-Performance Wood-Framed Walls: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christensen, D.
2011-01-01
Buildings are heavy consumers of energy, and residential building design is rapidly addressing topics to maximize energy conservation en route to net-zero energy consumption. Annual energy analysis of a building informs the choice among disparate energy measures, for cost, durability, occupant comfort, and whole-house energy use. Physics-based and empirical models of elements of a building are used in such analyses. High-performance wood-framed walls enable builders to construct homes that use much less than 40% of the energy consumed by similar homes built to minimum code. Modeling for these walls has considered physical features such as framing factor, insulation and framingmore » properties, roughness and convective effects, and air leakage. The thermal effects of fasteners used to construct these walls have not been fully evaluated, even though their thermal conductivity is orders of magnitudes higher than that of other building materials. Drywall screws and siding nails are considered in this finite element thermal conductivity analysis of wall sections that represent wood-framed walls that are often used in high-performance homes. Nails and screws reduce even the best walls' insulating performance by approximately 3% and become increasingly significant as the framing factor increases.« less
Simulating the Impact Response of Three Full-Scale Crash Tests of Cessna 172 Aircraft
NASA Technical Reports Server (NTRS)
Jackson, Karen E.; Fasanella, Edwin L.; Littell, Justin D.; Annett, Martin S.; Stimson, Chad M.
2017-01-01
During the summer of 2015, a series of three full-scale crash tests were performed at the Landing and Impact Research Facility located at NASA Langley Research Center of Cessna 172 aircraft. The first test (Test 1) represented a flare-to-stall emergency or hard landing onto a rigid surface. The second test (Test 2) represented a controlled-flight- into-terrain (CFIT) with a nose down pitch attitude of the aircraft, which impacted onto soft soil. The third test (Test 3) also represented a CFIT with a nose up pitch attitude of the aircraft, which resulted in a tail strike condition. Test 3 was also conducted onto soft soil. These crash tests were performed for the purpose of evaluating the performance of Emergency Locator Transmitters and to generate impact test data for model calibration. Finite element models were generated and impact analyses were conducted to simulate the three impact conditions using the commercial nonlinear, transient dynamic finite element code, LS-DYNA®. The objective of this paper is to summarize test-analysis results for the three full-scale crash tests.
Descriptive and Experimental Analyses of Potential Precursors to Problem Behavior
Borrero, Carrie S.W; Borrero, John C
2008-01-01
We conducted descriptive observations of severe problem behavior for 2 individuals with autism to identify precursors to problem behavior. Several comparative probability analyses were conducted in addition to lag-sequential analyses using the descriptive data. Results of the descriptive analyses showed that the probability of the potential precursor was greater given problem behavior compared to the unconditional probability of the potential precursor. Results of the lag-sequential analyses showed a marked increase in the probability of a potential precursor in the 1-s intervals immediately preceding an instance of problem behavior, and that the probability of problem behavior was highest in the 1-s intervals immediately following an instance of the precursor. We then conducted separate functional analyses of problem behavior and the precursor to identify respective operant functions. Results of the functional analyses showed that both problem behavior and the precursor served the same operant functions. These results replicate prior experimental analyses on the relation between problem behavior and precursors and extend prior research by illustrating a quantitative method to identify precursors to more severe problem behavior. PMID:18468281
(Boiling water reactor (BWR) CORA experiments)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ott, L.J.
To participate in the 1990 CORA Workshop at Kernforschungszentrum Karlsruhe (KfK) GmbH, Karlsruhe, FRG, on October 1--4, and to participate in detailed discussions on October 5 with the KfK CORA Boiling Water Reactor (BWR) experiments. The traveler attended the 1990 CORA Workshop at KfK, FRG. Participation included the presentation of a paper on work performed by the Boiling Water Reactor Core Melt Progression Phenomena Program at Oak Ridge National Laboratory (ORNL) on posttest analyses of CORA BWR experiments. The Statement of Work (November 1989) for the BWR Core Melt Progression Phenomena Program provides for pretest and posttest analyses of themore » BWR CORA experiments performed at KfK. Additionally, it is intended that ORNL personnel participate in the planning process for future CORA BWR experiments. For these purposes, meetings were held with KfK staff to discuss such topics as (1) experimental test schedule, (2) BWR test conduct, (3) perceived BWR experimental needs, and (4) KfK operational staff needs with respect to ORNL support. 19 refs.« less
Bearing tester data compilation, analysis, and reporting and bearing math modeling
NASA Technical Reports Server (NTRS)
1986-01-01
A test condition data base was developed for the Bearing and Seal Materials Tester (BSMT) program which permits rapid retrieval of test data for trend analysis and evaluation. A model was developed for the Space shuttle Main Engine (SSME) Liquid Oxygen (LOX) turbopump shaft/bearing system. The model was used to perform parametric analyses to determine the sensitivity of bearing operating characteristics and temperatures to variations in: axial preload, contact friction, coolant flow and subcooling, heat transfer coefficients, outer race misalignments, and outer race to isolator clearances. The bearing program ADORE (Advanced Dynamics of Rolling Elements) was installed on the UNIVAC 1100/80 computer system and is operational. ADORE is an advanced FORTRAN computer program for the real time simulation of the dynamic performance of rolling bearings. A model of the 57 mm turbine-end bearing is currently being checked out. Analyses were conducted to estimate flow work energy for several flow diverter configurations and coolant flow rates for the LOX BSMT.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lindberg, Michael J.
2010-09-28
Between October 14, 2009 and February 22, 2010 sediment samples were received from 100-BC Decision Unit for geochemical studies. This is an analytical data report for sediments received from CHPRC at the 100 BC 5 OU. The analyses for this project were performed at the 325 building located in the 300 Area of the Hanford Site. The analyses were performed according to Pacific Northwest National Laboratory (PNNL) approved procedures and/or nationally recognized test procedures. The data sets include the sample identification numbers, analytical results, estimated quantification limits (EQL), and quality control data. The preparatory and analytical quality control requirements, calibrationmore » requirements, acceptance criteria, and failure actions are defined in the on-line QA plan 'Conducting Analytical Work in Support of Regulatory Programs' (CAW). This QA plan implements the Hanford Analytical Services Quality Assurance Requirements Documents (HASQARD) for PNNL.« less
NASA Technical Reports Server (NTRS)
Putnam, T. W.; Burcham, F. W., Jr.; Andries, M. G.; Kelly, J. B.
1985-01-01
The NASA highly integrated digital electronic control (HIDEC) program is structured to conduct flight research into the benefits of integrating an aircraft flight control system with the engine control system. A brief description of the HIDEC system installed on an F-15 aircraft is provided. The adaptive engine control system (ADECS) mode is described in detail, together with simulation results and analyses that show the significant excess thrust improvements achievable with the ADECS mode. It was found that this increased thrust capability is accompanied by reduced fan stall margin and can be realized during flight conditions where engine face distortion is low. The results of analyses and simulations also show that engine thrust response is improved and that fuel consumption can be reduced. Although the performance benefits that accrue because of airframe and engine control integration are being demonstrated on an F-15 aircraft, the principles are applicable to advanced aircraft such as the advanced tactical fighter and advanced tactical aircraft.
Ramirez-Campillo, Rodrigo; Alvarez, Cristian; Gentil, Paulo; Loturco, Irineu; Sanchez-Sanchez, Javier; Izquierdo, Mikel; Moran, Jason; Nakamura, Fabio Y; Chaabene, Helmi; Granacher, Urs
2018-03-22
To compare the effects of short-term (i.e., 7 week) plyometric training applied before (PJT-B) or after (PJT-A) soccer practice on components of physical fitness in young soccer players, a single-blind randomized controlled trial was conducted. Post-pubertal boys aged 17.0±0.5 years were allocated to three groups: PJT-B (n=12), PJT-A (n=14), and control (CON; n=12). The outcome measures included tests to evaluate 20-m speed, standing long jump [SLJ], squat jump [SJ], countermovement jump [CMJ], and drop jump [DJ], 20-m multistage shuttle running speed [MSSRT], and Illinois change of direction speed [ICODT]. While the CON performed soccer-specific training, the PJT-A and PJT-B groups conducted the same soccer-specific sessions but replaced ∼11% of their time with plyometric training. The PJT-B group performed plyometric exercises after a warm-up program, and the PJT-A group conducted plyometric exercises ∼10 minutes after the completion of soccer training. Analyses of variance (ANOVAs) were used to detect differences between groups in all variables for pre- and post-training tests. Main effects of time (all p<.01; d=0.19-0.79) and group x time interactions (all p<.05; d=0.17-0.76) were observed for all examined variables. Post hoc analyses revealed significant increases in the PJT-B group (SLJ: 9.4%, d=1.7; CMJ: 11.2%, d=0.75; 20-m MSSRT: 9.0%, d=0.77) and the PJT-A group (SLJ: 3.1%, d=0.7; CMJ: 4.9%, d=0.27; 20-m MSSRT: 9.0%, d=0.76). Post hoc analyses also revealed significant increases in the PJT-B group (20-m speed: -7.4%, d=0.75; 20-cm DJ reactive strength index: 19.1%, d=1.4; SJ: 6.3%, d=0.44; ICODT results: -4.2%, d=1.1). In general, our study revealed that plyometric training is effective in improving measures of physical fitness in young male soccer players when combined with regular soccer training. More specifically, larger training induced effects on physical fitness were registered if plyometric training was conducted prior to soccer specific training.
Missing value imputation for microarray data: a comprehensive comparison study and a web tool.
Chiu, Chia-Chun; Chan, Shih-Yao; Wang, Chung-Ching; Wu, Wei-Sheng
2013-01-01
Microarray data are usually peppered with missing values due to various reasons. However, most of the downstream analyses for microarray data require complete datasets. Therefore, accurate algorithms for missing value estimation are needed for improving the performance of microarray data analyses. Although many algorithms have been developed, there are many debates on the selection of the optimal algorithm. The studies about the performance comparison of different algorithms are still incomprehensive, especially in the number of benchmark datasets used, the number of algorithms compared, the rounds of simulation conducted, and the performance measures used. In this paper, we performed a comprehensive comparison by using (I) thirteen datasets, (II) nine algorithms, (III) 110 independent runs of simulation, and (IV) three types of measures to evaluate the performance of each imputation algorithm fairly. First, the effects of different types of microarray datasets on the performance of each imputation algorithm were evaluated. Second, we discussed whether the datasets from different species have different impact on the performance of different algorithms. To assess the performance of each algorithm fairly, all evaluations were performed using three types of measures. Our results indicate that the performance of an imputation algorithm mainly depends on the type of a dataset but not on the species where the samples come from. In addition to the statistical measure, two other measures with biological meanings are useful to reflect the impact of missing value imputation on the downstream data analyses. Our study suggests that local-least-squares-based methods are good choices to handle missing values for most of the microarray datasets. In this work, we carried out a comprehensive comparison of the algorithms for microarray missing value imputation. Based on such a comprehensive comparison, researchers could choose the optimal algorithm for their datasets easily. Moreover, new imputation algorithms could be compared with the existing algorithms using this comparison strategy as a standard protocol. In addition, to assist researchers in dealing with missing values easily, we built a web-based and easy-to-use imputation tool, MissVIA (http://cosbi.ee.ncku.edu.tw/MissVIA), which supports many imputation algorithms. Once users upload a real microarray dataset and choose the imputation algorithms, MissVIA will determine the optimal algorithm for the users' data through a series of simulations, and then the imputed results can be downloaded for the downstream data analyses.
Sanders, Gillian D; Neumann, Peter J; Basu, Anirban; Brock, Dan W; Feeny, David; Krahn, Murray; Kuntz, Karen M; Meltzer, David O; Owens, Douglas K; Prosser, Lisa A; Salomon, Joshua A; Sculpher, Mark J; Trikalinos, Thomas A; Russell, Louise B; Siegel, Joanna E; Ganiats, Theodore G
2016-09-13
Since publication of the report by the Panel on Cost-Effectiveness in Health and Medicine in 1996, researchers have advanced the methods of cost-effectiveness analysis, and policy makers have experimented with its application. The need to deliver health care efficiently and the importance of using analytic techniques to understand the clinical and economic consequences of strategies to improve health have increased in recent years. To review the state of the field and provide recommendations to improve the quality of cost-effectiveness analyses. The intended audiences include researchers, government policy makers, public health officials, health care administrators, payers, businesses, clinicians, patients, and consumers. In 2012, the Second Panel on Cost-Effectiveness in Health and Medicine was formed and included 2 co-chairs, 13 members, and 3 additional members of a leadership group. These members were selected on the basis of their experience in the field to provide broad expertise in the design, conduct, and use of cost-effectiveness analyses. Over the next 3.5 years, the panel developed recommendations by consensus. These recommendations were then reviewed by invited external reviewers and through a public posting process. The concept of a "reference case" and a set of standard methodological practices that all cost-effectiveness analyses should follow to improve quality and comparability are recommended. All cost-effectiveness analyses should report 2 reference case analyses: one based on a health care sector perspective and another based on a societal perspective. The use of an "impact inventory," which is a structured table that contains consequences (both inside and outside the formal health care sector), intended to clarify the scope and boundaries of the 2 reference case analyses is also recommended. This special communication reviews these recommendations and others concerning the estimation of the consequences of interventions, the valuation of health outcomes, and the reporting of cost-effectiveness analyses. The Second Panel reviewed the current status of the field of cost-effectiveness analysis and developed a new set of recommendations. Major changes include the recommendation to perform analyses from 2 reference case perspectives and to provide an impact inventory to clarify included consequences.
Hydraulic Conductivity Measurements Barrow 2014
Katie McKnight; Tim Kneafsey; Craig Ulrich; Jil Geller
2015-02-22
Six individual ice cores were collected from Barrow Environmental Observatory in Barrow, Alaska, in May of 2013 as part of the Next Generation Ecosystem Experiment (NGEE). Each core was drilled from a different location at varying depths. A few days after drilling, the cores were stored in coolers packed with dry ice and flown to Lawrence Berkeley National Laboratory (LBNL) in Berkeley, CA. 3-dimensional images of the cores were constructed using a medical X-ray computed tomography (CT) scanner at 120kV. Hydraulic conductivity samples were extracted from these cores at LBNL Richmond Field Station in Richmond, CA, in February 2014 by cutting 5 to 8 inch segments using a chop saw. Samples were packed individually and stored at freezing temperatures to minimize any changes in structure or loss of ice content prior to analysis. Hydraulic conductivity was determined through falling head tests using a permeameter [ELE International, Model #: K-770B]. After approximately 12 hours of thaw, initial falling head tests were performed. Two to four measurements were collected on each sample and collection stopped when the applied head load exceeded 25% change from the original load. Analyses were performed between 2 to 3 times for each sample. The final hydraulic conductivity calculations were computed using methodology of Das et al., 1985.
Ikeda, Hiroshi; Furukawa, Hisataka
2015-04-01
cThis study examined the interactive effect of management by group goals and job interdependence on employee's activities in terms of task and contextual performance. A survey was conducted among 140 Japanese employees. Results indicated that management by group goals was related only to contextual performance. Job interdependence, however, had a direct effect on both task and contextual performance. Moreover, moderated regression analyses revealed that for work groups requiring higher interdependence among employees, management by group goals had a positive relation to contextual performance but not to task performance. When interdependence was not necessarily required, however, management by group goals had no relation to contextual performance and even negatively impacted task performance, respectively. These results show that management by group goals affects task and contextual performance, and that this effect is moderated by job interdependence. This provides a theoretical extension as well as a practical application to the setting and management of group goals.
MEGALEX: A megastudy of visual and auditory word recognition.
Ferrand, Ludovic; Méot, Alain; Spinelli, Elsa; New, Boris; Pallier, Christophe; Bonin, Patrick; Dufau, Stéphane; Mathôt, Sebastiaan; Grainger, Jonathan
2018-06-01
Using the megastudy approach, we report a new database (MEGALEX) of visual and auditory lexical decision times and accuracy rates for tens of thousands of words. We collected visual lexical decision data for 28,466 French words and the same number of pseudowords, and auditory lexical decision data for 17,876 French words and the same number of pseudowords (synthesized tokens were used for the auditory modality). This constitutes the first large-scale database for auditory lexical decision, and the first database to enable a direct comparison of word recognition in different modalities. Different regression analyses were conducted to illustrate potential ways to exploit this megastudy database. First, we compared the proportions of variance accounted for by five word frequency measures. Second, we conducted item-level regression analyses to examine the relative importance of the lexical variables influencing performance in the different modalities (visual and auditory). Finally, we compared the similarities and differences between the two modalities. All data are freely available on our website ( https://sedufau.shinyapps.io/megalex/ ) and are searchable at www.lexique.org , inside the Open Lexique search engine.
Enhanced ionization efficiency in TIMS analyses of plutonium and americium using porous ion emitters
Baruzzini, Matthew L.; Hall, Howard L.; Watrous, Matthew G.; ...
2016-12-05
Investigations of enhanced sample utilization in thermal ionization mass spectrometry (TIMS) using porous ion emitter (PIE) techniques for the analyses of trace quantities of americium and plutonium were performed. Repeat ionization efficiency (i.e., the ratio of ions detected to atoms loaded on the filament) measurements were conducted on sample sizes ranging from 10–100 pg for americium and 1–100 pg for plutonium using PIE and traditional (i.e., a single, zone-refined rhenium, flat filament ribbon with a carbon ionization enhancer) TIMS filament sources. When compared to traditional filaments, PIEs exhibited an average boost in ionization efficiency of ~550% for plutonium and ~1100%more » for americium. A maximum average efficiency of 1.09% was observed at a 1 pg plutonium sample loading using PIEs. Supplementary trials were conducted using newly developed platinum PIEs to analyze 10 pg mass loadings of plutonium. As a result, platinum PIEs exhibited an additional ~134% boost in ion yield over standard PIEs and ~736% over traditional filaments at the same sample loading level.« less
Stuper-Szablewska, Kinga; Rogoziński, Tomasz; Perkowski, Juliusz
2017-06-27
Wood compounds, especially sterols, are connected with the level of contamination with microscopic fungi. Within this study, tests were conducted on wood dust samples collected at various work stations in a pine and birch timber conversion plant. Their contamination with mycobiota was measured as the concentration of ergosterol (ERG) by ultra performance liquid chromatography (UPLC). Another aim of this study was to assess the effect of contamination with microscopic fungi on the sterol contents in wood dusts. Analyses were conducted on five sterols: desmosterol, cholesterol, lanosterol, stigmasterol, and β-sitosterol using UPLC and their presence was confirmed using gas chromatography/mass spectrometry (GC/MS). The results of chemical analyses showed the greatest contamination with mycobiota in birch wood dust. We also observed varied contents of individual sterols depending on the wood dust type. Their highest concentration was detected in birch dust. The discriminant analysis covering all tested compounds as predictors showed complete separation of all tested wood dust types. The greatest discriminatory power was found for stigmasterol, desmosterol, and ergosterol.
NASA Astrophysics Data System (ADS)
Payrastre, Olivier; Bourgin, François; Lebouc, Laurent; Le Bihan, Guillaume; Gaume, Eric
2017-04-01
The October 2015 flash-floods in south eastern France caused more than twenty fatalities, high damages and large economic losses in high density urban areas of the Mediterranean coast, including the cities of Mandelieu-La Napoule, Cannes and Antibes. Following a post event survey and preliminary analyses conducted within the framework of the Hymex project, we set up an entire simulation chain at the regional scale to better understand this outstanding event. Rainfall-runoff simulations, inundation mapping and a first estimation of the impacts are conducted following the approach developed and successfully applied for two large flash-flood events in two different French regions (Gard in 2002 and Var in 2010) by Le Bihan (2016). A distributed rainfall-runoff model applied at high resolution for the whole area - including numerous small ungauged basins - is used to feed a semi-automatic hydraulic approach (Cartino method) applied along the river network - including small tributaries. Estimation of the impacts is then performed based on the delineation of the flooded areas and geographic databases identifying buildings and population at risk.
NASA Technical Reports Server (NTRS)
Rivera, Jose A., Jr.
1989-01-01
An experimental and analytical study was conducted at Mach 0.7 to investigate the effects of spanwise curvature on flutter. Two series of rectangular planform wings of aspect ration 1.5 and curvature ranging from zero (uncurved) to 1.04/ft were flutter tested in the NASA Langley Transonic Dynamics Tunnel (TDT). One series consisted of models with a NACA 65 A010 airfoil section and the other of flat plate cross section models. Flutter analyses were conducted for correlation with the experimental results by using structural finite element methods to perform vibration analysis and two aerodynamic theories to obtain unsteady aerodynamic load calculations. The experimental results showed that for one series of models the flutter dynamic pressure increased significantly with curvature while for the other series of models the flutter dynamic pressure decreased with curvature. The flutter analyses, which generally predicted the experimental results, indicated that the difference in behavior of the two series of models was primarily due to differences in their structural properties.
NASA Astrophysics Data System (ADS)
Toyoshima, Morio; Takenaka, Hideki; Shoji, Yozo; Takayama, Yoshihisa; Koyama, Yoshisada; Kunimori, Hiroo
2012-05-01
Bi-directional ground-to-satellite laser communication experiments were successfully performed between the optical ground station developed by the National Institute of Information and Communications Technology (NICT), located in Koganei City in suburban Tokyo, and a low earth orbit (LEO) satellite, the "Kirari" Optical Inter-orbit Communications Engineering Test Satellite (OICETS). The experiments were conducted in cooperation with the Japan Aerospace Exploration Agency (JAXA), and called the Kirari Optical communication Demonstration Experiments with the NICT optical ground station (or KODEN). The ground-to-OICETS laser communication experiment was the first in-orbit demonstration involving the LEO satellite. The laser communication experiment was conducted since March 2006. The polarization characteristics of an artificial laser source in space, such as Stokes parameters, and the degree of polarization were measured through space-to-ground atmospheric transmission paths, which results contribute to the link estimation for quantum key distribution via space and provide the potential for enhancements in quantum cryptography on a global scale in the future. The Phase-5 experiment, international laser communications experiments were also successfully conducted with four optical ground stations located in the United States, Spain, Germany, and Japan from April 2009 to September 2009. The purpose of the Phase-5 experiment was to establish OICETS-to-ground laser communication links from the different optical ground stations and the statistical analyses such as the normalized power, scintillation index, probability density function, auto-covariance function, and power spectral density were performed. Thus the applicability of the satellite laser communications was demonstrated, aiming not only for geostationary earth orbit-LEO links but also for ground-to-LEO optical links. This paper presents the results of the KODEN experiments and mainly introduces the common analyses among the different optical ground stations.
Evaluation of a respiratory symptom diary for clinical studies of idiopathic pulmonary fibrosis.
Bacci, Elizabeth Dansie; O'Quinn, Sean; Leidy, Nancy Kline; Murray, Lindsey; Vernon, Margaret
2018-01-01
There are no validated patient diaries for evaluating respiratory symptoms in idiopathic pulmonary fibrosis (IPF). To evaluate the performance properties of the chronic obstructive pulmonary disease (COPD) Evaluating Respiratory Symptoms™ (E-RS™: COPD) measure in patients with IPF. Concept elicitation and cognitive interviews were conducted with IPF patients to evaluate content validity, including comprehensiveness, relevance, and interpretability of E-RS™ items in this patient population. Secondary analyses of IPF clinical study data were performed to evaluate the scoring structure of the tool. With modifications, reliability, validity, and responsiveness of the instrument (E-RS™: IPF) were evaluated. Qualitative interviews (n = 30) were conducted. During the elicitation interviews (n = 20), concept saturation for IPF respiratory symptoms was achieved; all respiratory symptoms covered by the E-RS™ were endorsed by ≥ 30% of the sample. During cognitive interviews (n = 10), all participants found the items interpretable and relevant. Factor analyses conducted via secondary analysis of IPF clinical study data identified no total score and four symptom scales: Chest, Breathlessness, Cough, and Sputum. Reliability of each scale was high (internal consistency [α] >0.85); 2-day reproducibility (ICC >0.88). Validity was supported through significant (P < 0.0001) relationships with the St. George's Respiratory Questionnaire (SGRQ), the University of California, San Diego Shortness of Breath Questionnaire (UCSD-SOBQ), and other variables. The scales were responsive to change when evaluated using SGRQ Symptoms, UCSD-SOBQ, and Patient Global Impression of Change as anchors (P < 0.01 to P < 0.0001). The E-RS™: IPF is a valid, reliable, and responsive tool for evaluating respiratory symptoms in patients with IPF. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Results of advanced battery technology evaluations for electric vehicle applications
NASA Astrophysics Data System (ADS)
Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.
1992-10-01
Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis and Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, in a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during 1991-1992 on both single cells and multi-cell modules that encompass eight battery technologies (Na/S, Li/MS (M=metal), Ni/MH, Ni/Cd, Ni/Zn, Ni/Fe, Zn/Br, and Pb-acid). These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most-promising R&D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R&D programs, a comparison of battery technologies, and basic data for modeling.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tournier, J.; El-Genk, M.S.; Huang, L.
1999-01-01
The Institute of Space and Nuclear Power Studies at the University of New Mexico has developed a computer simulation of cylindrical geometry alkali metal thermal-to-electric converter cells using a standard Fortran 77 computer code. The objective and use of this code was to compare the experimental measurements with computer simulations, upgrade the model as appropriate, and conduct investigations of various methods to improve the design and performance of the devices for improved efficiency, durability, and longer operational lifetime. The Institute of Space and Nuclear Power Studies participated in vacuum testing of PX series alkali metal thermal-to-electric converter cells and developedmore » the alkali metal thermal-to-electric converter Performance Evaluation and Analysis Model. This computer model consisted of a sodium pressure loss model, a cell electrochemical and electric model, and a radiation/conduction heat transfer model. The code closely predicted the operation and performance of a wide variety of PX series cells which led to suggestions for improvements to both lifetime and performance. The code provides valuable insight into the operation of the cell, predicts parameters of components within the cell, and is a useful tool for predicting both the transient and steady state performance of systems of cells.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tournier, J.; El-Genk, M.S.; Huang, L.
1999-01-01
The Institute of Space and Nuclear Power Studies at the University of New Mexico has developed a computer simulation of cylindrical geometry alkali metal thermal-to-electric converter cells using a standard Fortran 77 computer code. The objective and use of this code was to compare the experimental measurements with computer simulations, upgrade the model as appropriate, and conduct investigations of various methods to improve the design and performance of the devices for improved efficiency, durability, and longer operational lifetime. The Institute of Space and Nuclear Power Studies participated in vacuum testing of PX series alkali metal thermal-to-electric converter cells and developedmore » the alkali metal thermal-to-electric converter Performance Evaluation and Analysis Model. This computer model consisted of a sodium pressure loss model, a cell electrochemical and electric model, and a radiation/conduction heat transfer model. The code closely predicted the operation and performance of a wide variety of PX series cells which led to suggestions for improvements to both lifetime and performance. The code provides valuable insight into the operation of the cell, predicts parameters of components within the cell, and is a useful tool for predicting both the transient and steady state performance of systems of cells.« less
NASA Technical Reports Server (NTRS)
Englar, Robert J.; Willie, F. Scott; Lee, Warren J.
1999-01-01
In the Task I portion of this NASA research grant, configuration development and experimental investigations have been conducted on a series of pneumatic high-lift and control surface devices applied to a generic High Speed Civil Transport (HSCT) model configuration to determine their potential for improved aerodynamic performance, plus stability and control of higher performance aircraft. These investigations were intended to optimize pneumatic lift and drag performance; provide adequate control and longitudinal stability; reduce separation flowfields at high angle of attack; increase takeoff/climbout lift-to-drag ratios; and reduce system complexity and weight. Experimental aerodynamic evaluations were performed on a semi-span HSCT generic model with improved fuselage fineness ratio and with interchangeable plain flaps, blown flaps, pneumatic Circulation Control Wing (CCW) high-lift configurations, plain and blown canards, a novel Circulation Control (CC) cylinder blown canard, and a clean cruise wing for reference. Conventional tail power was also investigated for longitudinal trim capability. Also evaluated was unsteady pulsed blowing of the wing high-lift system to determine if reduced pulsed mass flow rates and blowing requirements could be made to yield the same lift as that resulting from steady-state blowing. Depending on the pulsing frequency applied, reduced mass flow rates were indeed found able to provide lift augmentation at lesser blowing values than for the steady conditions. Significant improvements in the aerodynamic characteristics leading to improved performance and stability/control were identified, and the various components were compared to evaluate the pneumatic potential of each. Aerodynamic results were provided to the Georgia Tech Aerospace System Design Lab. to conduct the companion system analyses and feasibility study (Task 2) of theses concepts applied to an operational advanced HSCT aircraft. Results and conclusions from these experimental evaluations are presented herein, as are recommendations for further development and follow-on investigations. Also provided as an Appendix for reference are the basic results from the previous pneumatic HSCT investigations.
Hagger, Martin S; Chan, Derwin K C; Protogerou, Cleo; Chatzisarantis, Nikos L D
2016-08-01
Synthesizing research on social cognitive theories applied to health behavior is an important step in the development of an evidence base of psychological factors as targets for effective behavioral interventions. However, few meta-analyses of research on social cognitive theories in health contexts have conducted simultaneous tests of theoretically-stipulated pattern effects using path analysis. We argue that conducting path analyses of meta-analytic effects among constructs from social cognitive theories is important to test nomological validity, account for mediation effects, and evaluate unique effects of theory constructs independent of past behavior. We illustrate our points by conducting new analyses of two meta-analyses of a popular theory applied to health behaviors, the theory of planned behavior. We conducted meta-analytic path analyses of the theory in two behavioral contexts (alcohol and dietary behaviors) using data from the primary studies included in the original meta-analyses augmented to include intercorrelations among constructs and relations with past behavior missing from the original analysis. Findings supported the nomological validity of the theory and its hypotheses for both behaviors, confirmed important model processes through mediation analysis, demonstrated the attenuating effect of past behavior on theory relations, and provided estimates of the unique effects of theory constructs independent of past behavior. Our analysis illustrates the importance of conducting a simultaneous test of theory-stipulated effects in meta-analyses of social cognitive theories applied to health behavior. We recommend researchers adopt this analytic procedure when synthesizing evidence across primary tests of social cognitive theories in health. Copyright © 2016 Elsevier Inc. All rights reserved.
How Big of a Problem is Analytic Error in Secondary Analyses of Survey Data?
West, Brady T; Sakshaug, Joseph W; Aurelien, Guy Alain S
2016-01-01
Secondary analyses of survey data collected from large probability samples of persons or establishments further scientific progress in many fields. The complex design features of these samples improve data collection efficiency, but also require analysts to account for these features when conducting analysis. Unfortunately, many secondary analysts from fields outside of statistics, biostatistics, and survey methodology do not have adequate training in this area, and as a result may apply incorrect statistical methods when analyzing these survey data sets. This in turn could lead to the publication of incorrect inferences based on the survey data that effectively negate the resources dedicated to these surveys. In this article, we build on the results of a preliminary meta-analysis of 100 peer-reviewed journal articles presenting analyses of data from a variety of national health surveys, which suggested that analytic errors may be extremely prevalent in these types of investigations. We first perform a meta-analysis of a stratified random sample of 145 additional research products analyzing survey data from the Scientists and Engineers Statistical Data System (SESTAT), which describes features of the U.S. Science and Engineering workforce, and examine trends in the prevalence of analytic error across the decades used to stratify the sample. We once again find that analytic errors appear to be quite prevalent in these studies. Next, we present several example analyses of real SESTAT data, and demonstrate that a failure to perform these analyses correctly can result in substantially biased estimates with standard errors that do not adequately reflect complex sample design features. Collectively, the results of this investigation suggest that reviewers of this type of research need to pay much closer attention to the analytic methods employed by researchers attempting to publish or present secondary analyses of survey data.
How Big of a Problem is Analytic Error in Secondary Analyses of Survey Data?
West, Brady T.; Sakshaug, Joseph W.; Aurelien, Guy Alain S.
2016-01-01
Secondary analyses of survey data collected from large probability samples of persons or establishments further scientific progress in many fields. The complex design features of these samples improve data collection efficiency, but also require analysts to account for these features when conducting analysis. Unfortunately, many secondary analysts from fields outside of statistics, biostatistics, and survey methodology do not have adequate training in this area, and as a result may apply incorrect statistical methods when analyzing these survey data sets. This in turn could lead to the publication of incorrect inferences based on the survey data that effectively negate the resources dedicated to these surveys. In this article, we build on the results of a preliminary meta-analysis of 100 peer-reviewed journal articles presenting analyses of data from a variety of national health surveys, which suggested that analytic errors may be extremely prevalent in these types of investigations. We first perform a meta-analysis of a stratified random sample of 145 additional research products analyzing survey data from the Scientists and Engineers Statistical Data System (SESTAT), which describes features of the U.S. Science and Engineering workforce, and examine trends in the prevalence of analytic error across the decades used to stratify the sample. We once again find that analytic errors appear to be quite prevalent in these studies. Next, we present several example analyses of real SESTAT data, and demonstrate that a failure to perform these analyses correctly can result in substantially biased estimates with standard errors that do not adequately reflect complex sample design features. Collectively, the results of this investigation suggest that reviewers of this type of research need to pay much closer attention to the analytic methods employed by researchers attempting to publish or present secondary analyses of survey data. PMID:27355817
EVALUATIONS ON ASR DAMAGE OF CONCRETE STRUCTURE AND ITS STRUCTURAL PERFORMANCE
NASA Astrophysics Data System (ADS)
Ueda, Naoshi; Nakamura, Hikaru; Kunieda, Minoru; Maeno, Hirofumi; Morishit, Noriaki; Asai, Hiroshi
In this paper, experiments and finite element analyses were conducted in order to evaluate effects of ASR on structural performance of RC and PC structures. From the experimental results, it was confirmed that the ASR expansion was affected by the restraint of reinforcement and the magnitude of prestress. The material properties of concrete damaged by ASR had anisotropic characteristics depending on the degree of ASR expansion. Therefore, when the structural performance of RC and PC structures were evaluated by using the material properties of core concrete, the direction and place where cylinder specimens were cored should be considered. On the other hand, by means of proposed analytical method, ASR expansion behaviors of RC and PC beams and changing of their structural performance were evaluated. As the results, it was confirmed that PC structure had much advantage comparing with RC structure regarding the structural performance under ASR damage because of restraint by prestress against the ASR.
Hui, Siu-kuen Azor; Grandner, Michael A.
2015-01-01
Objective To examine the relationships between employees’ trouble sleeping and absenteeism, work performance, and healthcare expenditures over a two year period. Methods Utilizing the Kansas State employee wellness program (EWP) dataset from 2008–2009, multinomial logistic regression analyses were conducted with trouble sleeping as the predictor and absenteeism, work performance, and healthcare costs as the outcomes. Results EWP participants (N=11,698 in 2008; 5,636 followed up in 2009) who had higher levels of sleep disturbance were more likely to be absent from work (all p < 0.0005), have lower work performance ratings (all p < 0.0005), and have higher healthcare costs (p < 0.0005). Longitudinally, more trouble sleeping was significantly related to negative changes in all outcomes. Conclusions Employees’ trouble sleeping, even at a sub-clinical level, negatively impacts on work attendance, work performance, and healthcare costs. PMID:26461857
Hui, Siu-kuen Azor; Grandner, Michael A
2015-10-01
To examine the relationships between employees' trouble sleeping and absenteeism, work performance, and health care expenditures over a 2-year period. Utilizing the Kansas State employee wellness program (EWP) data set from 2008 to 2009, multinomial logistic regression analyses were conducted with trouble sleeping as the predictor and absenteeism, work performance, and health care costs as the outcomes. EWP participants (N = 11,698 in 2008; 5636 followed up in 2009) who had higher levels of sleep disturbance were more likely to be absent from work (all P < 0.0005), have lower work performance ratings (all P < 0.0005), and have higher health care costs (P < 0.0005). Longitudinally, more trouble sleeping was significantly related to negative changes in all outcomes. Employees' trouble sleeping, even at a subclinical level, negatively impacts on work attendance, work performance, and health care costs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simbeck, D.J.
1993-12-31
Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Toxicity testing of copper sulfate reference toxicant was conducted from May 12--21, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed an LC{sub 50} value of 1.12 mg Cu/L which is lower than the value of 2.02 mg Cu/L obtained inmore » a previous test. Too few tests have been conducted with copper as the toxicant to determine a normal range of values. Attachments to this report include: Toxicity test bench sheets and statistical analyses; Copper analysis request and results; and Personnel training documentation.« less
Radioactive Waste Management Complex performance assessment: Draft
DOE Office of Scientific and Technical Information (OSTI.GOV)
Case, M.J.; Maheras, S.J.; McKenzie-Carter, M.A.
1990-06-01
A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Resultsmore » of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations.« less
Carbon Nanotubes as FET Channel: Analog Design Optimization considering CNT Parameter Variability
NASA Astrophysics Data System (ADS)
Samar Ansari, Mohd.; Tripathi, S. K.
2017-08-01
Carbon nanotubes (CNTs), both single-walled as well as multi-walled, have been employed in a plethora of applications pertinent to semiconductor materials and devices including, but not limited to, biotechnology, material science, nanoelectronics and nano-electro mechanical systems (NEMS). The Carbon Nanotube Field Effect Transistor (CNFET) is one such electronic device which effectively utilizes CNTs to achieve a boost in the channel conduction thereby yielding superior performance over standard MOSFETs. This paper explores the effects of variability in CNT physical parameters viz. nanotube diameter, pitch, and number of CNT in the transistor channel, on the performance of a chosen analog circuit. It is further shown that from the analyses performed, an optimal design of the CNFETs can be derived for optimizing the performance of the analog circuit as per a given specification set.
Results of the Excreta Bioassay Quality Control Program for April 1, 2009 through March 31, 2010
DOE Office of Scientific and Technical Information (OSTI.GOV)
Antonio, Cheryl L.
2012-07-19
A total of 58 urine samples and 10 fecal samples were submitted during the report period (April 1, 2009 through March 31, 2010) to General Engineering Laboratories, South Carolina by the Hanford Internal Dosimetry Program (IDP) to check the accuracy, precision, and detection levels of their analyses. Urine analyses for Sr, 238Pu, 239Pu, 241Am, 243Am 235U, 238U, elemental uranium and fecal analyses for 241Am, 238Pu and 239Pu were tested this year as well as four tissue samples for 238Pu, 239Pu, 241Am and 241Pu. The number of QC urine samples submitted during the report period represented 1.3% of the total samplesmore » submitted. In addition to the samples provided by IDP, GEL was also required to conduct their own QC program, and submit the results of analyses to IDP. About 33% of the analyses processed by GEL during the third year of this contract were quality control samples. GEL tested the performance of 21 radioisotopes, all of which met or exceeded the specifications in the Statement of Work within statistical uncertainty (Table 4).« less
Results of The Excreta Bioassay Quality Control Program For April 1, 2010 Through March 31, 2011
DOE Office of Scientific and Technical Information (OSTI.GOV)
Antonio, Cheryl L.
2012-07-19
A total of 76 urine samples and 10 spiked fecal samples were submitted during the report period (April 1, 2010 through March 31, 2011) to GEL Laboratories, LLC in South Carolina by the Hanford Internal Dosimetry Program (IDP) to check the accuracy, precision, and detection levels of their analyses. Urine analyses for 14C, Sr, for 238Pu, 239Pu, 241Am, 243Am, 235U, 238U, 238U-mass and fecal analyses for 241Am, 238Pu and 239Pu were tested this year. The number of QC urine samples submitted during the report period represented 1.1% of the total samples submitted. In addition to the samples provided by IDP,more » GEL was also required to conduct their own QC program, and submit the results of analyses to IDP. About 31% of the analyses processed by GEL during the first year of contract 112512 were quality control samples. GEL tested the performance of 23 radioisotopes, all of which met or exceeded the specifications in the Statement of Work within statistical uncertainty except the slightly elevated relative bias for 243,244Cm (Table 4).« less
Effectiveness of Light Sources on In-Office Dental Bleaching: A Systematic Review and Meta-Analyses.
SoutoMaior, J R; de Moraes, Sld; Lemos, Caa; Vasconcelos, Bc do E; Montes, Majr; Pellizzer, E P
2018-06-12
A systematic review and meta-analyses were performed to evaluate the efficacy of tooth color change and sensitivity of teeth following in-office bleaching with and without light gel activation in adult patients. This review was registered at PROSPERO (CRD 42017060574) and is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Electronic systematic searches of PubMed/MEDLINE, Web of Science, and the Cochrane Library were conducted for published articles. Only randomized clinical trials among adults that compared in-office bleaching with and without light activation with the same bleaching gel concentrations were selected. The outcomes were tooth color change and tooth sensitivity prevalence and intensity. Twenty-three articles from 1054 data sources met the eligibility criteria. After title and abstract screening, 39 studies remained. Sixteen studies were further excluded. Twenty-three studies remained for qualitative analyses and 20 for meta-analyses of primary and secondary outcomes. No significant differences in tooth color change or tooth sensitivity incidence were found between the compared groups; however, tooth sensitivity intensity decreased when light sources were applied. The use of light sources for in-office bleaching is not imperative to achieve esthetic clinical results.