Pilot Field Test Study

NASA Technical Reports Server (NTRS)

Sherriff, Abigail

2015-01-01

The Field Test study is currently in full swing, preceded by the successful completion of the Pilot Field Test study that paved the way for collecting data on the astronauts in the medical tent in Kazakhstan. Abigail Sherriff worked alongside Logan Dobbe on one Field Test aspect to determine foot clearance over obstacles (5cm, 10cm, and 15cm) using APDM Inc. Internal Measurement Units (IMU) worn by the astronauts. They created a program to accurately calculate foot clearance using the accelerometer, magnetometer, and gyroscope data with the IMUs attached to the top of the shoes. To validate the functionality of their program, they completed a successful study on test subjects performing various tasks in an optical motion studio, considered a gold standard in biomechanics research. Future work will include further validation and expanding the program to include other analyses.

Field assessment of balance in 10 to 14 year old children, reproducibility and validity of the Nintendo Wii board.

PubMed

Larsen, Lisbeth Runge; Jørgensen, Martin Grønbech; Junge, Tina; Juul-Kristensen, Birgit; Wedderkopp, Niels

2014-06-10

Because body proportions in childhood are different to those in adulthood, children have a relatively higher centre of mass location. This biomechanical difference and the fact that children's movements have not yet fully matured result in different sway performances in children and adults. When assessing static balance, it is essential to use objective, sensitive tools, and these types of measurement have previously been performed in laboratory settings. However, the emergence of technologies like the Nintendo Wii Board (NWB) might allow balance assessment in field settings. As the NWB has only been validated and tested for reproducibility in adults, the purpose of this study was to examine reproducibility and validity of the NWB in a field setting, in a population of children. Fifty-four 10-14 year-olds from the CHAMPS-Study DK performed four different balance tests: bilateral stance with eyes open (1), unilateral stance on dominant (2) and non-dominant leg (3) with eyes open, and bilateral stance with eyes closed (4). Three rounds of the four tests were completed with the NWB and with a force platform (AMTI). To assess reproducibility, an intra-day test-retest design was applied with a two-hour break between sessions. Bland-Altman plots supplemented by Minimum Detectable Change (MDC) and concordance correlation coefficient (CCC) demonstrated satisfactory reproducibility for the NWB and the AMTI (MDC: 26.3-28.2%, CCC: 0.76-0.86) using Centre Of Pressure path Length as measurement parameter. Bland-Altman plots demonstrated satisfactory concurrent validity between the NWB and the AMTI, supplemented by satisfactory CCC in all tests (CCC: 0.74-0.87). The ranges of the limits of agreement in the validity study were comparable to the limits of agreement of the reproducibility study. Both NWB and AMTI have satisfactory reproducibility for testing static balance in a population of children. Concurrent validity of NWB compared with AMTI was satisfactory. Furthermore, the results from the concurrent validity study were comparable to the reproducibility results of the NWB and the AMTI. Thus, NWB has the potential to replace the AMTI in field settings in studies including children. Future studies are needed to examine intra-subject variability and to test the predictive validity of NWB.

Field assessment of balance in 10 to 14 year old children, reproducibility and validity of the Nintendo Wii board

PubMed Central

2014-01-01

Background Because body proportions in childhood are different to those in adulthood, children have a relatively higher centre of mass location. This biomechanical difference and the fact that children’s movements have not yet fully matured result in different sway performances in children and adults. When assessing static balance, it is essential to use objective, sensitive tools, and these types of measurement have previously been performed in laboratory settings. However, the emergence of technologies like the Nintendo Wii Board (NWB) might allow balance assessment in field settings. As the NWB has only been validated and tested for reproducibility in adults, the purpose of this study was to examine reproducibility and validity of the NWB in a field setting, in a population of children. Methods Fifty-four 10–14 year-olds from the CHAMPS-Study DK performed four different balance tests: bilateral stance with eyes open (1), unilateral stance on dominant (2) and non-dominant leg (3) with eyes open, and bilateral stance with eyes closed (4). Three rounds of the four tests were completed with the NWB and with a force platform (AMTI). To assess reproducibility, an intra-day test-retest design was applied with a two-hour break between sessions. Results Bland-Altman plots supplemented by Minimum Detectable Change (MDC) and concordance correlation coefficient (CCC) demonstrated satisfactory reproducibility for the NWB and the AMTI (MDC: 26.3-28.2%, CCC: 0.76-0.86) using Centre Of Pressure path Length as measurement parameter. Bland-Altman plots demonstrated satisfactory concurrent validity between the NWB and the AMTI, supplemented by satisfactory CCC in all tests (CCC: 0.74-0.87). The ranges of the limits of agreement in the validity study were comparable to the limits of agreement of the reproducibility study. Conclusion Both NWB and AMTI have satisfactory reproducibility for testing static balance in a population of children. Concurrent validity of NWB compared with AMTI was satisfactory. Furthermore, the results from the concurrent validity study were comparable to the reproducibility results of the NWB and the AMTI. Thus, NWB has the potential to replace the AMTI in field settings in studies including children. Future studies are needed to examine intra-subject variability and to test the predictive validity of NWB. PMID:24913461

Toward Development of a Stochastic Wake Model: Validation Using LES and Turbine Loads

DOE PAGES

Moon, Jae; Manuel, Lance; Churchfield, Matthew; ...

2017-12-28

Wind turbines within an array do not experience free-stream undisturbed flow fields. Rather, the flow fields on internal turbines are influenced by wakes generated by upwind unit and exhibit different dynamic characteristics relative to the free stream. The International Electrotechnical Commission (IEC) standard 61400-1 for the design of wind turbines only considers a deterministic wake model for the design of a wind plant. This study is focused on the development of a stochastic model for waked wind fields. First, high-fidelity physics-based waked wind velocity fields are generated using Large-Eddy Simulation (LES). Stochastic characteristics of these LES waked wind velocity field,more » including mean and turbulence components, are analyzed. Wake-related mean and turbulence field-related parameters are then estimated for use with a stochastic model, using Multivariate Multiple Linear Regression (MMLR) with the LES data. To validate the simulated wind fields based on the stochastic model, wind turbine tower and blade loads are generated using aeroelastic simulation for utility-scale wind turbine models and compared with those based directly on the LES inflow. The study's overall objective is to offer efficient and validated stochastic approaches that are computationally tractable for assessing the performance and loads of turbines operating in wakes.« less

Toward Development of a Stochastic Wake Model: Validation Using LES and Turbine Loads

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

Moon, Jae; Manuel, Lance; Churchfield, Matthew

Wind turbines within an array do not experience free-stream undisturbed flow fields. Rather, the flow fields on internal turbines are influenced by wakes generated by upwind unit and exhibit different dynamic characteristics relative to the free stream. The International Electrotechnical Commission (IEC) standard 61400-1 for the design of wind turbines only considers a deterministic wake model for the design of a wind plant. This study is focused on the development of a stochastic model for waked wind fields. First, high-fidelity physics-based waked wind velocity fields are generated using Large-Eddy Simulation (LES). Stochastic characteristics of these LES waked wind velocity field,more » including mean and turbulence components, are analyzed. Wake-related mean and turbulence field-related parameters are then estimated for use with a stochastic model, using Multivariate Multiple Linear Regression (MMLR) with the LES data. To validate the simulated wind fields based on the stochastic model, wind turbine tower and blade loads are generated using aeroelastic simulation for utility-scale wind turbine models and compared with those based directly on the LES inflow. The study's overall objective is to offer efficient and validated stochastic approaches that are computationally tractable for assessing the performance and loads of turbines operating in wakes.« less

A study in the founding of applied behavior analysis through its publications.

PubMed

Morris, Edward K; Altus, Deborah E; Smith, Nathaniel G

2013-01-01

This article reports a study of the founding of applied behavior analysis through its publications. Our methods included hand searches of sources (e.g., journals, reference lists), search terms (i.e., early, applied, behavioral, research, literature), inclusion criteria (e.g., the field's applied dimension), and (d) challenges to their face and content validity. Our results were 36 articles published between 1959 and 1967 that we organized into 4 groups: 12 in 3 programs of research and 24 others. Our discussion addresses (a) limitations in our method (e.g., the completeness of our search), (b) challenges to the validity of our methods and results (e.g., convergent validity), and (c) priority claims about the field's founding. We conclude that the claims are irresolvable because identification of the founding publications depends significantly on methods and because the field's founding was an evolutionary process. We close with suggestions for future research.

A Study in the Founding of Applied Behavior Analysis Through Its Publications

PubMed Central

Morris, Edward K.; Altus, Deborah E.; Smith, Nathaniel G.

2013-01-01

This article reports a study of the founding of applied behavior analysis through its publications. Our methods included hand searches of sources (e.g., journals, reference lists), search terms (i.e., early, applied, behavioral, research, literature), inclusion criteria (e.g., the field's applied dimension), and (d) challenges to their face and content validity. Our results were 36 articles published between 1959 and 1967 that we organized into 4 groups: 12 in 3 programs of research and 24 others. Our discussion addresses (a) limitations in our method (e.g., the completeness of our search), (b) challenges to the validity of our methods and results (e.g., convergent validity), and (c) priority claims about the field's founding. We conclude that the claims are irresolvable because identification of the founding publications depends significantly on methods and because the field's founding was an evolutionary process. We close with suggestions for future research. PMID:25729133

Comparison of on-site field measured inorganic arsenic in rice with laboratory measurements using a field deployable method: Method validation.

PubMed

Mlangeni, Angstone Thembachako; Vecchi, Valeria; Norton, Gareth J; Raab, Andrea; Krupp, Eva M; Feldmann, Joerg

2018-10-15

A commercial arsenic field kit designed to measure inorganic arsenic (iAs) in water was modified into a field deployable method (FDM) to measure iAs in rice. While the method has been validated to give precise and accurate results in the laboratory, its on-site field performance has not been evaluated. This study was designed to test the method on-site in Malawi in order to evaluate its accuracy and precision in determination of iAs on-site by comparing with a validated reference method and giving original data on inorganic arsenic in Malawian rice and rice-based products. The method was validated by using the established laboratory-based HPLC-ICPMS. Statistical tests indicated there were no significant differences between on-site and laboratory iAs measurements determined using the FDM (p = 0.263, ά = 0.05) and between on-site measurements and measurements determined using HPLC-ICP-MS (p = 0.299, ά = 0.05). This method allows quick (within 1 h) and efficient screening of rice containing iAs concentrations on-site. Copyright © 2018 Elsevier Ltd. All rights reserved.

GOSAT validation out standing in the field: A case study of satellite validation using the SSEC Portable Atmospheric Research Center (SPARC)

NASA Astrophysics Data System (ADS)

Wagner, T. J.; Borg, L. A.; Feltz, M.; Gero, P. J.; Knuteson, R. O.; Olson, E.

2016-12-01

The Space Science and Engineering Center (SSEC) at the University of Wisconsin-Madison has developed the SSEC Portable Atmospheric Research Center (SPARC), a mobile 11 m trailer that houses numerous in situ and ground-based remote sensing instruments. Available instrumentation includes the Atmospheric Emitted Radiance Interferometer (AERI), a hyperspectral infrared radiometer from which trace gas concentrations and profiles of temperature and water vapor can be retrieved; the High Spectral Resolution Lidar (HSRL), a multichannel lidar capable of directly retrieving profiles of optical depth and backscatter depolarization; and a Doppler lidar wind profiler. The remote instrumentation suite is complemented by surface meteorology observations and a radiosonde ground station. Collectively, these instruments enable SPARC to participate in a wide variety of field studies, including meteorological field experiments and ground-based satellite calibration and validation studies. In August 2016, SPARC traveled to the Chequamegon National Forest in northern Wisconsin for a two week long deployment alongside the WLEF-TV tower. This 447 m tower houses long-term observations of thermodynamic and atmospheric composition at multiple heights, enabling studies of phenomena like atmospheric/land surface interactions and carbon uptake. During this deployment, SPARC launched radiosondes coincident with clear-sky overpasses of the Greenhouse gases Observing SATellite (GOSAT). Thermodynamic profiles from the radiosondes and AERI combined with the trace gas observations from the tower were used to validate the GOSAT observations of carbon dioxide and methane. The on-site presence of SPARC allowed for better characterization of the environment and greater observational certainty than was possible with the tower alone. Examples from this particular validation study as well as a discussion of how SPARC can contribute to other satellite calibration and validation investigations will be presented.

Collection of LAI and FPAR Data Over The Terra Core Sites

NASA Technical Reports Server (NTRS)

Myneni, Ranga B.; Knjazihhin, J.; Tian, Y.; Wang, Y.

2001-01-01

The objective of our effort was to collect and archive data on LAI (leaf area index) and FPAR (Fraction of Photosynthetically active Radiation absorbed by vegetation) at the EOS Core validation sites as well as to validate and evaluate global fields of LAI and FPAR derived from atmospherically corrected MODIS (Moderate Resolution Imaging Spectrometer) surface reflectance data by comparing these fields with the EOS Core validation data set. The above has been accomplished by: (a) the participation in selected field campaigns within the EOS Validation Program; (b) the processing of the collected data so that suitable comparison between field measurements and the MODIS LAI/FPAR fields can be made; (c) the comparison of the MODAS LAI/FRAM fields with the EOS Terra Core validation data set.

Validation of an Evaluation Model for Learning Management Systems

ERIC Educational Resources Information Center

Kim, S. W.; Lee, M. G.

2008-01-01

This study aims to validate a model for evaluating learning management systems (LMS) used in e-learning fields. A survey of 163 e-learning experts, regarding 81 validation items developed through literature review, was used to ascertain the importance of the criteria. A concise list of explanatory constructs, including two principle factors, was…

Assessing the Validity of an Annual Survey for Measuring Principal Leadership Practice

ERIC Educational Resources Information Center

Camburn, Eric M.; Huff, Jason T.; Goldring, Ellen B.; May, Henry

2010-01-01

Because research has shown that principals' practices can significantly impact teaching and learning in their schools through multiple avenues, it is critical to understand the validity of tools that measure principal practice. While the field has relied heavily on self-report surveys, little is known about their validity. This study compares…

Estimating the spatial distribution of field-applied mushroom compost in the Brandywine-Christina River Basin using multispectral remote sensing

NASA Astrophysics Data System (ADS)

Moxey, Kelsey A.

The world's greatest concentration of mushroom farms is settled within the Brandywine-Christina River Basin in Chester County in southeastern Pennsylvania. This industry produces a nutrient-rich byproduct known as spent mushroom compost, which has been traditionally applied to local farm fields as an organic fertilizer and soil amendment. While mushroom compost has beneficial properties, the possible over-application to farm fields could potentially degrade stream water quality. The goal of this study was to estimate the spatial extent and intensity of field-applied mushroom compost. We applied a remote sensing approach using Landsat multispectral imagery. We utilized the soil line technique, using the red and near-infrared bands, to estimate differences in soil wetness as a result of increased soil organic matter content from mushroom compost. We validated soil wetness estimates by examining the spectral response of references sites. We performed a second independent validation analysis using expert knowledge from agricultural extension agents. Our results showed that the soil line based wetness index worked well. The spectral validation illustrated that compost changes the spectral response of soil because of changes in wetness. The independent expert validation analysis produced a strong significant correlation between our remotely-sensed wetness estimates and the empirical ratings of compost application intensities. Overall, the methodology produced realistic spatial distributions of field-applied compost application intensities across the study area. These spatial distributions will be used for follow-up studies to assess the effect of spent mushroom compost on stream water quality.

Culture Training: Validation Evidence for the Culture Assimilator.

ERIC Educational Resources Information Center

Mitchell, Terence R.; And Others

The culture assimilator, a programed self-instructional approach to culture training, is described and a series of laboratory experiments and field studies validating the culture assimilator are reviewed. These studies show that the culture assimilator is an effective method of decreasing some of the stress experienced when one works with people…

Criterion-Related Validity of the Distance- and Time-Based Walk/Run Field Tests for Estimating Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis.

PubMed

Mayorga-Vega, Daniel; Bocanegra-Parrilla, Raúl; Ornelas, Martha; Viciana, Jesús

2016-01-01

The main purpose of the present meta-analysis was to examine the criterion-related validity of the distance- and time-based walk/run tests for estimating cardiorespiratory fitness among apparently healthy children and adults. Relevant studies were searched from seven electronic bibliographic databases up to August 2015 and through other sources. The Hunter-Schmidt's psychometric meta-analysis approach was conducted to estimate the population criterion-related validity of the following walk/run tests: 5,000 m, 3 miles, 2 miles, 3,000 m, 1.5 miles, 1 mile, 1,000 m, ½ mile, 600 m, 600 yd, ¼ mile, 15 min, 12 min, 9 min, and 6 min. From the 123 included studies, a total of 200 correlation values were analyzed. The overall results showed that the criterion-related validity of the walk/run tests for estimating maximum oxygen uptake ranged from low to moderate (rp = 0.42-0.79), with the 1.5 mile (rp = 0.79, 0.73-0.85) and 12 min walk/run tests (rp = 0.78, 0.72-0.83) having the higher criterion-related validity for distance- and time-based field tests, respectively. The present meta-analysis also showed that sex, age and maximum oxygen uptake level do not seem to affect the criterion-related validity of the walk/run tests. When the evaluation of an individual's maximum oxygen uptake attained during a laboratory test is not feasible, the 1.5 mile and 12 min walk/run tests represent useful alternatives for estimating cardiorespiratory fitness. As in the assessment with any physical fitness field test, evaluators must be aware that the performance score of the walk/run field tests is simply an estimation and not a direct measure of cardiorespiratory fitness.

Multivariate statistical assessment of predictors of firefighters' muscular and aerobic work capacity.

PubMed

Lindberg, Ann-Sofie; Oksa, Juha; Antti, Henrik; Malm, Christer

2015-01-01

Physical capacity has previously been deemed important for firefighters physical work capacity, and aerobic fitness, muscular strength, and muscular endurance are the most frequently investigated parameters of importance. Traditionally, bivariate and multivariate linear regression statistics have been used to study relationships between physical capacities and work capacities among firefighters. An alternative way to handle datasets consisting of numerous correlated variables is to use multivariate projection analyses, such as Orthogonal Projection to Latent Structures. The first aim of the present study was to evaluate the prediction and predictive power of field and laboratory tests, respectively, on firefighters' physical work capacity on selected work tasks. Also, to study if valid predictions could be achieved without anthropometric data. The second aim was to externally validate selected models. The third aim was to validate selected models on firefighters' and on civilians'. A total of 38 (26 men and 12 women) + 90 (38 men and 52 women) subjects were included in the models and the external validation, respectively. The best prediction (R2) and predictive power (Q2) of Stairs, Pulling, Demolition, Terrain, and Rescue work capacities included field tests (R2 = 0.73 to 0.84, Q2 = 0.68 to 0.82). The best external validation was for Stairs work capacity (R2 = 0.80) and worst for Demolition work capacity (R2 = 0.40). In conclusion, field and laboratory tests could equally well predict physical work capacities for firefighting work tasks, and models excluding anthropometric data were valid. The predictive power was satisfactory for all included work tasks except Demolition.

Measuring Stakeholder Participation in Evaluation: An Empirical Validation of the Participatory Evaluation Measurement Instrument (PEMI)

ERIC Educational Resources Information Center

Daigneault, Pierre-Marc; Jacob, Steve; Tremblay, Joel

2012-01-01

Background: Stakeholder participation is an important trend in the field of program evaluation. Although a few measurement instruments have been proposed, they either have not been empirically validated or do not cover the full content of the concept. Objectives: This study consists of a first empirical validation of a measurement instrument that…

Using GLEAMS to Select Environmental Windows for Herbicide Application in Forests

Treesearch

M.C. Smith; J.L. Michael; W.G. Koisel; D.G. Nealy

1994-01-01

Observed herbicide runoff and groundwater data from a pine-release herbicide application study near Gainesville, Florida were used to validate the GLEAMS model hydrology and pesticide component for forest application. The study revealed that model simulations agreed relatively well with the field data for the one-year study. Following validation, a modified version of...

Initial design and performance of the near surface unmanned aircraft system sensor suite in support of the GOES-R field campaign

NASA Astrophysics Data System (ADS)

Pearlman, Aaron J.; Padula, Francis; Shao, Xi; Cao, Changyong; Goodman, Steven J.

2016-09-01

One of the main objectives of the Geostationary Operational Environmental Satellite R-Series (GOES-R) field campaign is to validate the SI traceability of the Advanced Baseline Imager. The campaign plans include a feasibility demonstration study for new near surface unmanned aircraft system (UAS) measurement capability that is being developed to meet the challenges of validating geostationary sensors. We report our progress in developing our initial systems by presenting the design and preliminary characterization results of the sensor suite. The design takes advantage of off-the-shelf technologies and fiber-based optical components to make hemispheric directional measurements from a UAS. The characterization results - including laboratory measurements of temperature effects and polarization sensitivity - are used to refine the radiometric uncertainty budget towards meeting the validation objectives for the campaign. These systems will foster improved validation capabilities for the GOES-R field campaign and other next generation satellite systems.

Field validation of secondary data sources: a novel measure of representativity applied to a Canadian food outlet database.

PubMed

Clary, Christelle M; Kestens, Yan

2013-06-19

Validation studies of secondary datasets used to characterize neighborhood food businesses generally evaluate how accurately the database represents the true situation on the ground. Depending on the research objectives, the characterization of the business environment may tolerate some inaccuracies (e.g. minor imprecisions in location or errors in business names). Furthermore, if the number of false negatives (FNs) and false positives (FPs) is balanced within a given area, one could argue that the database still provides a "fair" representation of existing resources in this area. Yet, traditional validation measures do not relax matching criteria, and treat FNs and FPs independently. Through the field validation of food businesses found in a Canadian database, this paper proposes alternative criteria for validity. Field validation of the 2010 Enhanced Points of Interest (EPOI) database (DMTI Spatial®) was performed in 2011 in 12 census tracts (CTs) in Montreal, Canada. Some 410 food outlets were extracted from the database and 484 were observed in the field. First, traditional measures of sensitivity and positive predictive value (PPV) accounting for every single mismatch between the field and the database were computed. Second, relaxed measures of sensitivity and PPV that tolerate mismatches in business names or slight imprecisions in location were assessed. A novel measure of representativity that further allows for compensation between FNs and FPs within the same business category and area was proposed. Representativity was computed at CT level as ((TPs +|FPs-FNs|)/(TPs+FNs)), with TPs meaning true positives, and |FPs-FNs| being the absolute value of the difference between the number of FNs and the number of FPs within each outlet category. The EPOI database had a "moderate" capacity to detect an outlet present in the field (sensitivity: 54.5%) or to list only the outlets that actually existed in the field (PPV: 64.4%). Relaxed measures of sensitivity and PPV were respectively 65.5% and 77.3%. The representativity of the EPOI database was 77.7%. The novel measure of representativity might serve as an alternative to traditional validity measures, and could be more appropriate in certain situations, depending on the nature and scale of the research question.

Scaling field data to calibrate and validate moderate spatial resolution remote sensing models

USGS Publications Warehouse

Baccini, A.; Friedl, M.A.; Woodcock, C.E.; Zhu, Z.

2007-01-01

Validation and calibration are essential components of nearly all remote sensing-based studies. In both cases, ground measurements are collected and then related to the remote sensing observations or model results. In many situations, and particularly in studies that use moderate resolution remote sensing, a mismatch exists between the sensor's field of view and the scale at which in situ measurements are collected. The use of in situ measurements for model calibration and validation, therefore, requires a robust and defensible method to spatially aggregate ground measurements to the scale at which the remotely sensed data are acquired. This paper examines this challenge and specifically considers two different approaches for aggregating field measurements to match the spatial resolution of moderate spatial resolution remote sensing data: (a) landscape stratification; and (b) averaging of fine spatial resolution maps. The results show that an empirically estimated stratification based on a regression tree method provides a statistically defensible and operational basis for performing this type of procedure. 

Validation of an Instrument to Measure Students' Motivation and Self-Regulation towards Technology Learning

ERIC Educational Resources Information Center

Liou, Pey-Yan; Kuo, Pei-Jung

2014-01-01

Background: Few studies have examined students' attitudinal perceptions of technology. There is no appropriate instrument to measure senior high school students' motivation and self-regulation toward technology learning among the current existing instruments in the field of technology education. Purpose: The present study is to validate an…

Groundwater Model Validation

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

Ahmed E. Hassan

2006-01-24

Models have an inherent uncertainty. The difficulty in fully characterizing the subsurface environment makes uncertainty an integral component of groundwater flow and transport models, which dictates the need for continuous monitoring and improvement. Building and sustaining confidence in closure decisions and monitoring networks based on models of subsurface conditions require developing confidence in the models through an iterative process. The definition of model validation is postulated as a confidence building and long-term iterative process (Hassan, 2004a). Model validation should be viewed as a process not an end result. Following Hassan (2004b), an approach is proposed for the validation process ofmore » stochastic groundwater models. The approach is briefly summarized herein and detailed analyses of acceptance criteria for stochastic realizations and of using validation data to reduce input parameter uncertainty are presented and applied to two case studies. During the validation process for stochastic models, a question arises as to the sufficiency of the number of acceptable model realizations (in terms of conformity with validation data). Using a hierarchical approach to make this determination is proposed. This approach is based on computing five measures or metrics and following a decision tree to determine if a sufficient number of realizations attain satisfactory scores regarding how they represent the field data used for calibration (old) and used for validation (new). The first two of these measures are applied to hypothetical scenarios using the first case study and assuming field data consistent with the model or significantly different from the model results. In both cases it is shown how the two measures would lead to the appropriate decision about the model performance. Standard statistical tests are used to evaluate these measures with the results indicating they are appropriate measures for evaluating model realizations. The use of validation data to constrain model input parameters is shown for the second case study using a Bayesian approach known as Markov Chain Monte Carlo. The approach shows a great potential to be helpful in the validation process and in incorporating prior knowledge with new field data to derive posterior distributions for both model input and output.« less

DIETARY EXPOSURES OF YOUNG CHILDREN, PART II: FIELD STUDY

EPA Science Inventory

A small, pilot field study was conducted to determine the adequacy of protocols for dietary exposure measurements. Samples were collected to estimate the amount of pesticides transferred from contaminated surfaces or hands to foods of young children and to validate a dietary mod...

Simulation study on combination of GRACE monthly gravity field solutions

NASA Astrophysics Data System (ADS)

Jean, Yoomin; Meyer, Ulrich; Jäggi, Adrian

2016-04-01

The GRACE monthly gravity fields from different processing centers are combined in the frame of the project EGSIEM. This combination is done on solution level first to define weights which will be used for a combination on normal equation level. The applied weights are based on the deviation of the individual gravity fields from the arithmetic mean of all involved gravity fields. This kind of weighting scheme relies on the assumption that the true gravity field is close to the arithmetic mean of the involved individual gravity fields. However, the arithmetic mean can be affected by systematic errors in individual gravity fields, which consequently results in inappropriate weights. For the future operational scientific combination service of GRACE monthly gravity fields, it is necessary to examine the validity of the weighting scheme also in possible extreme cases. To investigate this, we make a simulation study on the combination of gravity fields. Firstly, we show how a deviated gravity field can affect the combined solution in terms of signal and noise in the spatial domain. We also show the impact of systematic errors in individual gravity fields on the resulting combined solution. Then, we investigate whether the weighting scheme still works in the presence of outliers. The result of this simulation study will be useful to understand and validate the weighting scheme applied to the combination of the monthly gravity fields.

76 FR 28664 - Method 301-Field Validation of Pollutant Measurement Methods From Various Waste Media

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-18

... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 63 [OAR-2004-0080, FRL-9306-8] RIN 2060-AF00 Method 301--Field Validation of Pollutant Measurement Methods From Various Waste Media AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This action amends EPA's Method 301, Field Validation...

Validity and Reliability of Field-Based Measures for Assessing Movement Skill Competency in Lifelong Physical Activities: A Systematic Review.

PubMed

Hulteen, Ryan M; Lander, Natalie J; Morgan, Philip J; Barnett, Lisa M; Robertson, Samuel J; Lubans, David R

2015-10-01

It has been suggested that young people should develop competence in a variety of 'lifelong physical activities' to ensure that they can be active across the lifespan. The primary aim of this systematic review is to report the methodological properties, validity, reliability, and test duration of field-based measures that assess movement skill competency in lifelong physical activities. A secondary aim was to clearly define those characteristics unique to lifelong physical activities. A search of four electronic databases (Scopus, SPORTDiscus, ProQuest, and PubMed) was conducted between June 2014 and April 2015 with no date restrictions. Studies addressing the validity and/or reliability of lifelong physical activity tests were reviewed. Included articles were required to assess lifelong physical activities using process-oriented measures, as well as report either one type of validity or reliability. Assessment criteria for methodological quality were adapted from a checklist used in a previous review of sport skill outcome assessments. Movement skill assessments for eight different lifelong physical activities (badminton, cycling, dance, golf, racquetball, resistance training, swimming, and tennis) in 17 studies were identified for inclusion. Methodological quality, validity, reliability, and test duration (time to assess a single participant), for each article were assessed. Moderate to excellent reliability results were found in 16 of 17 studies, with 71% reporting inter-rater reliability and 41% reporting intra-rater reliability. Only four studies in this review reported test-retest reliability. Ten studies reported validity results; content validity was cited in 41% of these studies. Construct validity was reported in 24% of studies, while criterion validity was only reported in 12% of studies. Numerous assessments for lifelong physical activities may exist, yet only assessments for eight lifelong physical activities were included in this review. Generalizability of results may be more applicable if more heterogeneous samples are used in future research. Moderate to excellent levels of inter- and intra-rater reliability were reported in the majority of studies. However, future work should look to establish test-retest reliability. Validity was less commonly reported than reliability, and further types of validity other than content validity need to be established in future research. Specifically, predictive validity of 'lifelong physical activity' movement skill competency is needed to support the assertion that such activities provide the foundation for a lifetime of activity.

MLS Multipath Studies. Phase 3. Volume I. Overview and Propagation Model Validation/Refinement Studies.

DTIC Science & Technology

1979-04-25

Airport (Bedford, MA ) and Ft. Devens, MA. (2) validation of the models for building reflections based on elevation field measurements at JFK airport and...angles. 2-60 III. BUILDING REFLECTIONS A. Van Measurements at John F. Kennedy (JFK) International Airport, New York Figure 3-1 shows a map of JFK airport with

Field validation of the dnph method for aldehydes and ketones. Final report

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

Workman, G.S.; Steger, J.L.

1996-04-01

A stationary source emission test method for selected aldehydes and ketones has been validated. The method employs a sampling train with impingers containing 2,4-dinitrophenylhydrazine (DNPH) to derivatize the analytes. The resulting hydrazones are recovered and analyzed by high performance liquid chromatography. Nine analytes were studied; the method was validated for formaldehyde, acetaldehyde, propionaldehyde, acetophenone and isophorone. Acrolein, menthyl ethyl ketone, menthyl isobutyl ketone, and quinone did not meet the validation criteria. The study employed the validation techniques described in EPA method 301, which uses train spiking to determine bias, and collocated sampling trains to determine precision. The studies were carriedmore » out at a plywood veneer dryer and a polyester manufacturing plant.« less

Predictive validity of the Biomedical Admissions Test: an evaluation and case study.

PubMed

McManus, I C; Ferguson, Eamonn; Wakeford, Richard; Powis, David; James, David

2011-01-01

There has been an increase in the use of pre-admission selection tests for medicine. Such tests need to show good psychometric properties. Here, we use a paper by Emery and Bell [2009. The predictive validity of the Biomedical Admissions Test for pre-clinical examination performance. Med Educ 43:557-564] as a case study to evaluate and comment on the reporting of psychometric data in the field of medical student selection (and the comments apply to many papers in the field). We highlight pitfalls when reliability data are not presented, how simple zero-order associations can lead to inaccurate conclusions about the predictive validity of a test, and how biases need to be explored and reported. We show with BMAT that it is the knowledge part of the test which does all the predictive work. We show that without evidence of incremental validity it is difficult to assess the value of any selection tests for medicine.

Developing Statistical Physics Course Handout on Distribution Function Materials Based on Science, Technology, Engineering, and Mathematics

NASA Astrophysics Data System (ADS)

Riandry, M. A.; Ismet, I.; Akhsan, H.

2017-09-01

This study aims to produce a valid and practical statistical physics course handout on distribution function materials based on STEM. Rowntree development model is used to produce this handout. The model consists of three stages: planning, development and evaluation stages. In this study, the evaluation stage used Tessmer formative evaluation. It consists of 5 stages: self-evaluation, expert review, one-to-one evaluation, small group evaluation and field test stages. However, the handout is limited to be tested on validity and practicality aspects, so the field test stage is not implemented. The data collection technique used walkthroughs and questionnaires. Subjects of this study are students of 6th and 8th semester of academic year 2016/2017 Physics Education Study Program of Sriwijaya University. The average result of expert review is 87.31% (very valid category). One-to-one evaluation obtained the average result is 89.42%. The result of small group evaluation is 85.92%. From one-to-one and small group evaluation stages, averagestudent response to this handout is 87,67% (very practical category). Based on the results of the study, it can be concluded that the handout is valid and practical.

Measuring and Enhancing Creativity

ERIC Educational Resources Information Center

Mahboub, Kamyar C.; Portillo, Margaret B.; Liu, Yinhui; Chandraratna, Susantha

2004-01-01

The purpose of this study was to assess ways by which creativity may be enhanced in a design-oriented course. In order to demonstrate the validity of the approach, a statistically based study was employed. Additionally, the experiment was replicated in two design-oriented fields at the University of Kentucky. These fields were civil engineering…

What Do HPT Consultants Do for Performance Analysis?

ERIC Educational Resources Information Center

Kang, Sung

2017-01-01

This study was conducted to contribute to the field of Human Performance Technology (HPT) through the validation of the performance analysis process of the International Society for Performance Improvement (ISPI) HPT model, the most representative and frequently utilized process model in the HPT field. The study was conducted using content…

Surface Wave Dynamics in the Coastal Zone

DTIC Science & Technology

2014-09-30

also collected from the Duck measurement site, operated by the USACE Field Research Facility at Duck , North Carolina. The collection and validation...similar analysis for 10 storm periods using wave data collected at Duck , North Carolina. The preparations consist of creating a dedicated unstructured...validated in the Southern North Sea and Duck validation studies. The shallow water source terms for wave breaking and triad interactions are being

The western Mediterranean Sea: An area for a regional validation for TOPEX/Poseidon and a field for geophysical and oceanographic studies

NASA Technical Reports Server (NTRS)

Barlier, Francois; Balmino, G.; Boucher, Claude; Willis, P.; Biancale, R.; Menard, Yves; Vincent, P.; Bethoux, J. P.; Exertier, P.; Pierron, F.

1991-01-01

The research project has two kinds of objectives. The first is focused on the regional validation of the altimeter, orbit, and mean sea surface; it will be performed in close cooperation with the local validation performed at Lampedusa/Lampione (Italy). The second deals with the geophysical and oceanographic research of interest in this area.

Evaluation of nucleus segmentation in digital pathology images through large scale image synthesis

NASA Astrophysics Data System (ADS)

Zhou, Naiyun; Yu, Xiaxia; Zhao, Tianhao; Wen, Si; Wang, Fusheng; Zhu, Wei; Kurc, Tahsin; Tannenbaum, Allen; Saltz, Joel; Gao, Yi

2017-03-01

Digital histopathology images with more than 1 Gigapixel are drawing more and more attention in clinical, biomedical research, and computer vision fields. Among the multiple observable features spanning multiple scales in the pathology images, the nuclear morphology is one of the central criteria for diagnosis and grading. As a result it is also the mostly studied target in image computing. Large amount of research papers have devoted to the problem of extracting nuclei from digital pathology images, which is the foundation of any further correlation study. However, the validation and evaluation of nucleus extraction have yet been formulated rigorously and systematically. Some researches report a human verified segmentation with thousands of nuclei, whereas a single whole slide image may contain up to million. The main obstacle lies in the difficulty of obtaining such a large number of validated nuclei, which is essentially an impossible task for pathologist. We propose a systematic validation and evaluation approach based on large scale image synthesis. This could facilitate a more quantitatively validated study for current and future histopathology image analysis field.

Water vapour correction of the daily 1 km AVHRR global land dataset: Part I validation and use of the Water Vapour input field

USGS Publications Warehouse

DeFelice, Thomas P.; Lloyd, D.; Meyer, D.J.; Baltzer, T. T.; Piraina, P.

2003-01-01

An atmospheric correction algorithm developed for the 1 km Advanced Very High Resolution Radiometer (AVHRR) global land dataset was modified to include a near real-time total column water vapour data input field to account for the natural variability of atmospheric water vapour. The real-time data input field used for this study is the Television and Infrared Observational Satellite (TIROS) Operational Vertical Sounder (TOVS) Pathfinder A global total column water vapour dataset. It was validated prior to its use in the AVHRR atmospheric correction process using two North American AVHRR scenes, namely 13 June and 28 November 1996. The validation results are consistent with those reported by others and entail a comparison between TOVS, radiosonde, experimental sounding, microwave radiometer, and data from a hand-held sunphotometer. The use of this data layer as input to the AVHRR atmospheric correction process is discussed.

Field validation of secondary data sources: a novel measure of representativity applied to a Canadian food outlet database

PubMed Central

2013-01-01

Background Validation studies of secondary datasets used to characterize neighborhood food businesses generally evaluate how accurately the database represents the true situation on the ground. Depending on the research objectives, the characterization of the business environment may tolerate some inaccuracies (e.g. minor imprecisions in location or errors in business names). Furthermore, if the number of false negatives (FNs) and false positives (FPs) is balanced within a given area, one could argue that the database still provides a “fair” representation of existing resources in this area. Yet, traditional validation measures do not relax matching criteria, and treat FNs and FPs independently. Through the field validation of food businesses found in a Canadian database, this paper proposes alternative criteria for validity. Methods Field validation of the 2010 Enhanced Points of Interest (EPOI) database (DMTI Spatial®) was performed in 2011 in 12 census tracts (CTs) in Montreal, Canada. Some 410 food outlets were extracted from the database and 484 were observed in the field. First, traditional measures of sensitivity and positive predictive value (PPV) accounting for every single mismatch between the field and the database were computed. Second, relaxed measures of sensitivity and PPV that tolerate mismatches in business names or slight imprecisions in location were assessed. A novel measure of representativity that further allows for compensation between FNs and FPs within the same business category and area was proposed. Representativity was computed at CT level as ((TPs +|FPs-FNs|)/(TPs+FNs)), with TPs meaning true positives, and |FPs-FNs| being the absolute value of the difference between the number of FNs and the number of FPs within each outlet category. Results The EPOI database had a "moderate" capacity to detect an outlet present in the field (sensitivity: 54.5%) or to list only the outlets that actually existed in the field (PPV: 64.4%). Relaxed measures of sensitivity and PPV were respectively 65.5% and 77.3%. The representativity of the EPOI database was 77.7%. Conclusions The novel measure of representativity might serve as an alternative to traditional validity measures, and could be more appropriate in certain situations, depending on the nature and scale of the research question. PMID:23782570

Validation and Application of the ReaxFF Reactive Force Field to Hydrocarbon Oxidation Kinetics

DTIC Science & Technology

2016-06-23

AFRL-AFOSR-VA-TR-2016-0278 Validation and application of the ReaxFF reactive force field to hydrocarbon oxidation kinetics Adrianus Van Duin...application of the ReaxFF reactive force field to hydrocarbon oxidation kinetics 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-14-1-0355 5c.  PROGRAM...Chenoweth Dec14 Validation and application of the ReaxFF reactive force field to hydrocarbon oxidation kinetics DISTRIBUTION A: Distribution approved for

Criterion-Related Validity of the Distance- and Time-Based Walk/Run Field Tests for Estimating Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis

PubMed Central

Mayorga-Vega, Daniel; Bocanegra-Parrilla, Raúl; Ornelas, Martha; Viciana, Jesús

2016-01-01

Objectives The main purpose of the present meta-analysis was to examine the criterion-related validity of the distance- and time-based walk/run tests for estimating cardiorespiratory fitness among apparently healthy children and adults. Materials and Methods Relevant studies were searched from seven electronic bibliographic databases up to August 2015 and through other sources. The Hunter-Schmidt’s psychometric meta-analysis approach was conducted to estimate the population criterion-related validity of the following walk/run tests: 5,000 m, 3 miles, 2 miles, 3,000 m, 1.5 miles, 1 mile, 1,000 m, ½ mile, 600 m, 600 yd, ¼ mile, 15 min, 12 min, 9 min, and 6 min. Results From the 123 included studies, a total of 200 correlation values were analyzed. The overall results showed that the criterion-related validity of the walk/run tests for estimating maximum oxygen uptake ranged from low to moderate (rp = 0.42–0.79), with the 1.5 mile (rp = 0.79, 0.73–0.85) and 12 min walk/run tests (rp = 0.78, 0.72–0.83) having the higher criterion-related validity for distance- and time-based field tests, respectively. The present meta-analysis also showed that sex, age and maximum oxygen uptake level do not seem to affect the criterion-related validity of the walk/run tests. Conclusions When the evaluation of an individual’s maximum oxygen uptake attained during a laboratory test is not feasible, the 1.5 mile and 12 min walk/run tests represent useful alternatives for estimating cardiorespiratory fitness. As in the assessment with any physical fitness field test, evaluators must be aware that the performance score of the walk/run field tests is simply an estimation and not a direct measure of cardiorespiratory fitness. PMID:26987118

Reliability and Validity of the PAQ-C Questionnaire to Assess Physical Activity in Children

ERIC Educational Resources Information Center

Benítez-Porres, Javier; López-Fernández, Iván; Raya, Juan Francisco; Álvarez Carnero, Sabrina; Alvero-Cruz, José Ramón; Álvarez Carnero, Elvis

2016-01-01

Background: Physical activity (PA) assessment by questionnaire is a cornerstone in the field of sport epidemiology studies. The Physical Activity Questionnaire for Children (PAQ-C) has been used widely to assess PA in healthy school populations. The aim of this study was to evaluate the reliability and validity of the PAQ-C questionnaire in…

Beam dynamics validation of the Halbach Technology FFAG Cell for Cornell-BNL Energy Recovery Linac

NASA Astrophysics Data System (ADS)

Méot, F.; Tsoupas, N.; Brooks, S.; Trbojevic, D.

2018-07-01

The Cornell-BNL Electron Test Accelerator (CBETA), a 150 MeV energy recovery linac (ERL) now in construction at Cornell, employs a fixed-field alternating gradient optics return loop: a single beam line comprised of FFAG cells, which accepts four recirculated energies. CBETA FFAG cell uses Halbach permanent magnet technology, its design studies have covered an extended period of time supported by extensive particle dynamics simulations using computed 3-D field map models. This approach is discussed, and illustrated here, based on the final stage in these beam dynamics studies, namely the validation of a ultimate, optimized design of the Halbach cell.

Validation of the standardized field sobriety test battery at BACs below 0.10 percent

DOT National Transportation Integrated Search

1998-08-01

This study evaluated the accuracy of the National Highway Traffic Safety Administration's (NHTSA's) Standardized Field Sobriety Test (SFST) battery to assist officers in making arrest decisions for Driving While Intoxicated (DWI) at blood alcohol con...

Establishing the Test-Retest Reliability & Concurrent Validity for the Repeat Ice Skating Test (RIST) in Adolescent Male Ice Hockey Players

ERIC Educational Resources Information Center

Power, Allan; Faught, Brent E.; Przysucha, Eryk; McPherson, Moira; Montelpare, William

2012-01-01

In this study the authors examine the test-retest reliability and concurrent validity of the Repeat Ice Skating Test (RIST). This was an on-ice field anaerobic test that measured average peak power and was validated with 3 anaerobic lab tests: (a) vertical jump, (b) the Margaria-Kalamen stair test, and (c) the Wingate Anaerobic Test. The…

The Electromagnetic Field for a PEC Wedge Over a Grounded Dielectric Slab: 1. Formulation and Validation

NASA Astrophysics Data System (ADS)

Daniele, Vito G.; Lombardi, Guido; Zich, Rodolfo S.

2017-12-01

Complex scattering problems are often made by composite structures where wedges and penetrable substrates may interact at near field. In this paper (Part 1) together with its companion paper (Part 2) we study the canonical problem constituted of a Perfectly Electrically Conducting (PEC) wedge lying on a grounded dielectric slab with a comprehensive mathematical model based on the application of the Generalized Wiener-Hopf Technique (GWHT) with the help of equivalent circuital representations for linear homogenous regions (angular and layered regions). The proposed procedure is valid for the general case, and the papers focus on E-polarization. The solution is obtained using analytical and semianalytical approaches that reduce the Wiener-Hopf factorization to integral equations. Several numerical test cases validate the proposed method. The scope of Part 1 is to present the method and its validation applied to the problem. The companion paper Part 2 focuses on the properties of the solution, and it presents physical and engineering insights as Geometrical Theory of Diffraction (GTD)/Uniform Theory of Diffraction(UTD) coefficients, total far fields, modal fields, and excitation of surface and leaky waves for different kinds of source. The structure is of interest in antenna technologies and electromagnetic compatibility (tip on a substrate with guiding and antenna properties).

Development and Validation of Children's Responsible Environmental Behavior Scale

ERIC Educational Resources Information Center

Erdogan, Mehmet; Ok, Ahmet; Marcinkowski, Thomas Joseph

2012-01-01

Though environmentally responsible behavior (ERB) has been a focus of many studies in the field of environmental education, very few scales have been developed to assess children's ERB. In this regard, this article focuses on the development and validation of Children's Responsible Environmental Behavior Scale (CREBS) and also reports the…

Behavioral and Emotional Rating Scale: Two Studies of Convergent Validity

ERIC Educational Resources Information Center

Trout, Alexandra L.; Ryan, Joseph B.; La Vigne, Steven P.; Epstein, Michael H.

2003-01-01

As the field of mental health services shifts its focus to early intervention, the need to develop valid and reliable measures of young children's behavioral functioning is clear. Traditional assessment instruments have focused on deficits, problems, and pathologies to the exclusion of strengths and competencies. However, assessing child strengths…

Monte Carlo modeling of a 6 and 18 MV Varian Clinac medical accelerator for in-field and out-of-field dose calculations: development and validation

PubMed Central

Bednarz, Bryan; Xu, X George

2012-01-01

There is a serious and growing concern about the increased risk of radiation-induced second cancers and late tissue injuries associated with radiation treatment. To better understand and to more accurately quantify non-target organ doses due to scatter and leakage radiation from medical accelerators, a detailed Monte Carlo model of the medical linear accelerator is needed. This paper describes the development and validation of a detailed accelerator model of the Varian Clinac operating at 6 and 18 MV beam energies. Over 100 accelerator components have been defined and integrated using the Monte Carlo code MCNPX. A series of in-field and out-of-field dose validation studies were performed. In-field dose distributions calculated using the accelerator models were tuned to match measurement data that are considered the de facto ‘gold standard’ for the Varian Clinac accelerator provided by the manufacturer. Field sizes of 4 cm × 4 cm, 10 cm × 10 cm, 20 cm × 20 cm and 40 cm × 40 cm were considered. The local difference between calculated and measured dose on the percent depth dose curve was less than 2% for all locations. The local difference between calculated and measured dose on the dose profile curve was less than 2% in the plateau region and less than 2 mm in the penumbra region for all locations. Out-of-field dose profiles were calculated and compared to measurement data for both beam energies for field sizes of 4 cm × 4 cm, 10 cm × 10 cm and 20 cm × 20 cm. For all field sizes considered in this study, the average local difference between calculated and measured dose for the 6 and 18 MV beams was 14 and 16%, respectively. In addition, a method for determining neutron contamination in the 18 MV operating model was validated by comparing calculated in-air neutron fluence with reported calculations and measurements. The average difference between calculated and measured neutron fluence was 20%. As one of the most detailed accelerator models for both in-field and out-of-field dose calculations, the model will be combined with anatomically realistic computational patient phantoms into a computational framework to calculate non-target organ doses to patients from various radiation treatment plans. PMID:19141879

On Pfaffian Random Point Fields

NASA Astrophysics Data System (ADS)

Kargin, V.

2014-02-01

We study Pfaffian random point fields by using the Moore-Dyson quaternion determinants. First, we give sufficient conditions that ensure that a self-dual quaternion kernel defines a valid random point field, and then we prove a CLT for Pfaffian point fields. The proofs are based on a new quaternion extension of the Cauchy-Binet determinantal identity. In addition, we derive the Fredholm determinantal formulas for the Pfaffian point fields which use the quaternion determinant.

Crystal Plasticity Model Validation Using Combined High-Energy Diffraction Microscopy Data for a Ti-7Al Specimen

DOE PAGES

Turner, Todd J.; Shade, Paul A.; Bernier, Joel V.; ...

2016-11-18

High-Energy Diffraction Microscopy (HEDM) is a 3-d x-ray characterization method that is uniquely suited to measuring the evolving micromechanical state and microstructure of polycrystalline materials during in situ processing. The near-field and far-field configurations provide complementary information; orientation maps computed from the near-field measurements provide grain morphologies, while the high angular resolution of the far-field measurements provide intergranular strain tensors. The ability to measure these data during deformation in situ makes HEDM an ideal tool for validating micro-mechanical deformation models that make their predictions at the scale of individual grains. Crystal Plasticity Finite Element Models (CPFEM) are one such classmore » of micro-mechanical models. While there have been extensive studies validating homogenized CPFEM response at a macroscopic level, a lack of detailed data measured at the level of the microstructure has hindered more stringent model validation efforts. We utilize an HEDM dataset from an alphatitanium alloy (Ti-7Al), collected at the Advanced Photon Source, Argonne National Laboratory, under in situ tensile deformation. The initial microstructure of the central slab of the gage section, measured via near-field HEDM, is used to inform a CPFEM model. The predicted intergranular stresses for 39 internal grains are then directly compared to data from 4 far-field measurements taken between ~4% and ~80% of the macroscopic yield strength. In conclusion, the intergranular stresses from the CPFEM model and far-field HEDM measurements up to incipient yield are shown to be in good agreement, and implications for application of such an integrated computational/experimental approach to phenomena such as fatigue and crack propagation is discussed.« less

Conducting field studies for testing pesticide leaching models

USGS Publications Warehouse

Smith, Charles N.; Parrish, Rudolph S.; Brown, David S.

1990-01-01

A variety of predictive models are being applied to evaluate the transport and transformation of pesticides in the environment. These include well known models such as the Pesticide Root Zone Model (PRZM), the Risk of Unsaturated-Saturated Transport and Transformation Interactions for Chemical Concentrations Model (RUSTIC) and the Groundwater Loading Effects of Agricultural Management Systems Model (GLEAMS). The potentially large impacts of using these models as tools for developing pesticide management strategies and regulatory decisions necessitates development of sound model validation protocols. This paper offers guidance on many of the theoretical and practical problems encountered in the design and implementation of field-scale model validation studies. Recommendations are provided for site selection and characterization, test compound selection, data needs, measurement techniques, statistical design considerations and sampling techniques. A strategy is provided for quantitatively testing models using field measurements.

Assessment protocols of maximum oxygen consumption in young people with Down syndrome--a review.

PubMed

Seron, Bruna Barboza; Greguol, Márcia

2014-03-01

Maximum oxygen consumption is considered the gold standard measure of cardiorespiratory fitness. Young people with Down syndrome (DS) present low values of this indicator compared to their peers without disabilities and to young people with an intellectual disability but without DS. The use of reliable and valid assessment methods provides more reliable results for the diagnosis of cardiorespiratory fitness and the response of this variable to exercise. The aim of the present study was to review the literature on the assessment protocols used to measure maximum oxygen consumption in children and adolescents with Down syndrome giving emphasis to the protocols used, the validation process and their feasibility. The search was carried out in eight electronic databases--Scopus, Medline-Pubmed, Web of science, SportDiscus, Cinhal, Academic Search Premier, Scielo, and Lilacs. The inclusion criteria were: (a) articles which assessed VO2peak and/or VO2max (independent of the validation method), (b) samples composed of children and/or adolescents with Down syndrome, (c) participants of up to 20 years old, and (d) studies performed after 1990. Fifteen studies were selected and, of these, 11 measured the VO2peak using tests performed in a laboratory, 2 used field tests and the remaining 2 used both laboratory and field tests. The majority of the selected studies used maximal tests and conducted familiarization sessions. All the studies took into account the clinical conditions that could hamper testing or endanger the individuals. However, a large number of studies used tests which had not been specifically validated for the evaluated population. Finally, the search emphasized the small number of studies which use field tests to evaluate oxygen consumption. Copyright © 2013 Elsevier Ltd. All rights reserved.

Validity of field expedient devices to assess core temperature during exercise in the cold.

PubMed

Bagley, James R; Judelson, Daniel A; Spiering, Barry A; Beam, William C; Bartolini, J Albert; Washburn, Brian V; Carney, Keven R; Muñoz, Colleen X; Yeargin, Susan W; Casa, Douglas J

2011-12-01

Exposure to cold environments affects human performance and physiological function. Major medical organizations recommend rectal temperature (TREC) to evaluate core body temperature (TcORE) during exercise in the cold; however, other field expedient devices claim to measure TCORE. The purpose of this study was to determine if field expedient devices provide valid measures of TcRE during rest and exercise in the cold. Participants included 13 men and 12 women (age = 24 +/- 3 yr, height = 170.7 +/- 10.6 cm, mass = 73.4 +/- 16.7 kg, body fat = 18 +/- 7%) who reported being healthy and at least recreationally active. During 150 min of cold exposure, subjects sequentially rested for 30 min, cycled for 90 min (heart rate = 120-140 bpm), and rested for an additional 30 min. Investigators compared aural (T(AUR)), expensive axillary (T(AXLe)), inexpensive axillary (T(AXLi)), forehead (T(FOR)), gastrointestinal (T(GI)), expensive oral (T(ORLe)), inexpensive oral (T(ORLi)), and temporal (T(TEM)) temperatures to T(REc) every 15 min. Researchers used mean difference between each device and T(REC) (i.e., mean bias) as the primary criterion for validity. T(AUR), T(AXLe), T(AXLi), T(FOR), TORLe, T(ORLi), and TTEM provided significantly lower measures compared to T(REC) and fell below our validity criterion. T(GI) significantly exceeded T(REC) at three of eleven time points, but no significant difference existed between mean T(REC) and T(GI) across time. Only T(GI) achieved our validity criterion and compared favorably to T(REC). T(GI) offers a valid measurement with which to assess T(CORE) during rest and exercise in the cold; athletic trainers, mountain rescuers, and military medical personnel should avoid other field expedient devices in similar conditions.

Validation of a pulsed electric field process to pasteurize strawberry puree

USDA-ARS?s Scientific Manuscript database

An inexpensive data acquisition method was developed to validate the exact number and shape of the pulses applied during pulsed electric fields (PEF) processing. The novel validation method was evaluated in conjunction with developing a pasteurization PEF process for strawberry puree. Both buffered...

Exploring the Validity of a Second Language Intercultural Pragmatics Assessment Tool

ERIC Educational Resources Information Center

Timpe-Laughlin, Veronika; Choi, Ikkyu

2017-01-01

Pragmatics has been a key component of language competence frameworks. While the majority of second/foreign language (L2) pragmatics tests have targeted productive skills, the assessment of receptive pragmatic skills remains a developing field. This study explores validation evidence for a test of receptive L2 pragmatic ability called the American…

An empirical assessment of validation practices for molecular classifiers

PubMed Central

Castaldi, Peter J.; Dahabreh, Issa J.

2011-01-01

Proposed molecular classifiers may be overfit to idiosyncrasies of noisy genomic and proteomic data. Cross-validation methods are often used to obtain estimates of classification accuracy, but both simulations and case studies suggest that, when inappropriate methods are used, bias may ensue. Bias can be bypassed and generalizability can be tested by external (independent) validation. We evaluated 35 studies that have reported on external validation of a molecular classifier. We extracted information on study design and methodological features, and compared the performance of molecular classifiers in internal cross-validation versus external validation for 28 studies where both had been performed. We demonstrate that the majority of studies pursued cross-validation practices that are likely to overestimate classifier performance. Most studies were markedly underpowered to detect a 20% decrease in sensitivity or specificity between internal cross-validation and external validation [median power was 36% (IQR, 21–61%) and 29% (IQR, 15–65%), respectively]. The median reported classification performance for sensitivity and specificity was 94% and 98%, respectively, in cross-validation and 88% and 81% for independent validation. The relative diagnostic odds ratio was 3.26 (95% CI 2.04–5.21) for cross-validation versus independent validation. Finally, we reviewed all studies (n = 758) which cited those in our study sample, and identified only one instance of additional subsequent independent validation of these classifiers. In conclusion, these results document that many cross-validation practices employed in the literature are potentially biased and genuine progress in this field will require adoption of routine external validation of molecular classifiers, preferably in much larger studies than in current practice. PMID:21300697

A Florida validation study of the Standardized Field Sobriety Test (S.F.S.T.) battery

DOT National Transportation Integrated Search

1997-01-01

During the years 1975 - 1981, a battery of field sobriety tests was developed under funding by the National Highway Traffic Safety Administration (NHTSA), U.S. Department of Transportation (Burns and Moskowitz, 1977; Tharp, Burns, and Moskowitz, 1981...

Commissioning and validation of COMPASS system for VMAT patient specific quality assurance

NASA Astrophysics Data System (ADS)

Pimthong, J.; Kakanaporn, C.; Tuntipumiamorn, L.; Laojunun, P.; Iampongpaiboon, P.

2016-03-01

Pre-treatment patient specific quality assurance (QA) of advanced treatment techniques such as volumetric modulated arc therapy (VMAT) is one of important QA in radiotherapy. The fast and reliable dosimetric device is required. The objective of this study is to commission and validate the performance of COMPASS system for dose verification of VMAT technique. The COMPASS system is composed of an array of ionization detectors (MatriXX) mounted to the gantry using a custom holder and software for the analysis and visualization of QA results. We validated the COMPASS software for basic and advanced clinical application. For the basic clinical study, the simple open field in various field sizes were validated in homogeneous phantom. And the advanced clinical application, the fifteen prostate and fifteen nasopharyngeal cancers VMAT plans were chosen to study. The treatment plans were measured by the MatriXX. The doses and dose-volume histograms (DVHs) reconstructed from the fluence measurements were compared to the TPS calculated plans. And also, the doses and DVHs computed using collapsed cone convolution (CCC) Algorithm were compared with Eclipse TPS calculated plans using Analytical Anisotropic Algorithm (AAA) that according to dose specified in ICRU 83 for PTV.

The use of MR B+1 imaging for validation of FDTD electromagnetic simulations of human anatomies.

PubMed

Van den Berg, Cornelis A T; Bartels, Lambertus W; van den Bergen, Bob; Kroeze, Hugo; de Leeuw, Astrid A C; Van de Kamer, Jeroen B; Lagendijk, Jan J W

2006-10-07

In this study, MR B(+)(1) imaging is employed to experimentally verify the validity of FDTD simulations of electromagnetic field patterns in human anatomies. Measurements and FDTD simulations of the B(+)(1) field induced by a 3 T MR body coil in a human corpse were performed. It was found that MR B(+)(1) imaging is a sensitive method to measure the radiofrequency (RF) magnetic field inside a human anatomy with a precision of approximately 3.5%. A good correlation was found between the B(+)(1) measurements and FDTD simulations. The measured B(+)(1) pattern for a human pelvis consisted of a global, diagonal modulation pattern plus local B(+)(1) heterogeneties. It is believed that these local B(+)(1) field variations are the result of peaks in the induced electric currents, which could not be resolved by the FDTD simulations on a 5 mm(3) simulation grid. The findings from this study demonstrate that B(+)(1) imaging is a valuable experimental technique to gain more knowledge about the dielectric interaction of RF fields with the human anatomy.

Psychometric properties of the Chinese-version Quality of Nursing Work Life Scale.

PubMed

Lee, Ya-Wen; Dai, Yu-Tzu; McCreary, Linda L; Yao, Grace; Brooks, Beth A

2014-09-01

In this study, we developed and tested the psychometric properties of the Chinese-version Quality of Nursing Work Life Scale along seven subscales: supportive milieu with security and professional recognition, work arrangement and workload, work/home life balance, head nurse's/supervisor's management style, teamwork and communication, nursing staffing and patient care, and milieu of respect and autonomy. An instrument-development procedure with three phases was conducted in seven hospitals in 2010-2011. Phase I comprised translation and the cultural-adaptation process, phase II comprised a pilot study, and phase III comprised a field-testing process. Purposive sampling was used in the pilot study (n = 150) and the large field study (n = 1254). Five new items were added, and 85.7% of the original items were retained in the 41 item Chinese version. Principal component analysis revealed that a model accounted for 56.6% of the variance with acceptable internal consistency, concurrent validity, and discriminant validity. This study gave evidence of reliability and validity of the 41 item Chinese-version Quality of Nursing Work Life Scale. © 2014 Wiley Publishing Asia Pty Ltd.

Guiding Development Based Approach Practicum Vertebrates Taxonomy Scientific Study Program for Students of Biology Education

NASA Astrophysics Data System (ADS)

Arieska, M.; Syamsurizal, S.; Sumarmin, R.

2018-04-01

Students having difficulty in identifying and describing the vertebrate animals as well as less skilled in science process as practical. Increased expertise in scientific skills, one of which is through practical activities using practical guidance based on scientific approach. This study aims to produce practical guidance vertebrate taxonomy for biology education students PGRI STKIP West Sumatra valid. This study uses a model of Plomp development consisting of three phases: the initial investigation, floating or prototype stage, and the stage of assessment. Data collection instruments used in this study is a validation sheet guiding practicum. Data were analyzed descriptively based on data obtained from the field. The result of the development of practical guidance vertebrate taxonomic validity value of 3.22 is obtained with very valid category. Research and development has produced a practical guide based vertebrate taxonomic scientific approach very valid.

Validation of the Functional Assessment of Chronic Illness Therapy-Spiritual Well-being (FACIT-Sp12) on French Old People.

PubMed

Agli, Océane; Bailly, Nathalie; Ferrand, Claude

2017-04-01

The study aimed to develop a French version of the Functional Assessment of Chronic Illness Therapy-Spiritual Well-being short version (FACIT-Sp12), in order to provide a self-reported measure for French people in the field of gerontology. The study involving 63 nursing home residents was conducted to evaluate the construct validity, reliability, and convergence validity of the FACIT-Sp12. A confirmatory factor analysis corroborated a three-factor model (Meaning, Peace and Faith) with modifications for two items, also valid among people with cognitive impairment. Subscales showed good internal consistency and are correlated with quality of life and depression. In conclusion, the validated French version is an suitable instrument to study the maintenance and promotion of quality of life in the elderly.

Validation of a motor activity system by a robotically controlled vehicle and using standard reference compounds.

PubMed

Patterson, John P; Markgraf, Carrie G; Cirino, Maria; Bass, Alan S

2005-01-01

A series of experiments were undertaken to evaluate the accuracy, precision, specificity, and sensitivity of an automated, infrared photo beam-based open field motor activity system, the MotorMonitor v. 4.01, Hamilton-Kinder, LLC, for use in a good laboratory practices (GLP) Safety Pharmacology laboratory. This evaluation consisted of two phases: (1) system validation, employing known inputs using the EM-100 Controller Photo Beam Validation System, a robotically controlled vehicle representing a rodent and (2) biologic validation, employing groups of rats treated with the standard pharmacologic agents diazepam or D-amphetamine. The MotorMonitor's parameters that described the open-field activity of a subject were: basic movements, total distance, fine movements, x/y horizontal ambulations, rearing, and total rest time. These measurements were evaluated over a number of zones within each enclosure. System validation with the EM-100 Controller Photo Beam Validation System showed that all the parameters accurately and precisely measured what they were intended to measure, with the exception of fine movements and x/y ambulations. Biologic validation using the central nervous system depressant diazepam at 1, 2, or 5 mg/kg, i.p. produced the expected dose-dependent reduction in rat motor activity. In contrast, the central nervous system stimulant D-amphetamine produced the expected increases in rat motor activity at 0.1 and 1 mg/kg, i.p, demonstrating the specificity and sensitivity of the system. Taken together, these studies of the accuracy, precision, specificity, and sensitivity show the importance of both system and biologic validation in the evaluation of an automated open field motor activity system for use in a GLP compliant laboratory.

Validation of learning style measures: implications for medical education practice.

PubMed

Chapman, Dane M; Calhoun, Judith G

2006-06-01

It is unclear which learners would most benefit from the more individualised, student-structured, interactive approaches characteristic of problem-based and computer-assisted learning. The validity of learning style measures is uncertain, and there is no unifying learning style construct identified to predict such learners. This study was conducted to validate learning style constructs and to identify the learners most likely to benefit from problem-based and computer-assisted curricula. Using a cross-sectional design, 3 established learning style inventories were administered to 97 post-Year 2 medical students. Cognitive personality was measured by the Group Embedded Figures Test, information processing by the Learning Styles Inventory, and instructional preference by the Learning Preference Inventory. The 11 subscales from the 3 inventories were factor-analysed to identify common learning constructs and to verify construct validity. Concurrent validity was determined by intercorrelations of the 11 subscales. A total of 94 pre-clinical medical students completed all 3 inventories. Five meaningful learning style constructs were derived from the 11 subscales: student- versus teacher-structured learning; concrete versus abstract learning; passive versus active learning; individual versus group learning, and field-dependence versus field-independence. The concurrent validity of 10 of 11 subscales was supported by correlation analysis. Medical students most likely to thrive in a problem-based or computer-assisted learning environment would be expected to score highly on abstract, active and individual learning constructs and would be more field-independent. Learning style measures were validated in a medical student population and learning constructs were established for identifying learners who would most likely benefit from a problem-based or computer-assisted curriculum.

Multiscale GPS tomography during COPS: validation and applications

NASA Astrophysics Data System (ADS)

Champollion, Cédric; Flamant, Cyrille; Masson, Frédéric; Gégout, Pascal; Boniface, Karen; Richard, Evelyne

2010-05-01

Accurate 3D description of the water vapour field is of interest for process studies such as convection initiation. None of the current techniques (LIDAR, satellite, radio soundings, GPS) can provide an all weather continuous 3D field of moisture. The combination of GPS tomography with radio-soundings (and/or LIDAR) has been used for such process studies using both advantages of vertically resolved soundings and high temporal density of GPS measurements. GPS tomography has been used at short scale (10 km horizontal resolution but in a 50 km² area) for process studies such as the ESCOMPTE experiment (Bastin et al., 2005) and at larger scale (50 km horizontal resolution) during IHOP_2002. But no extensive statistical validation has been done so far. The overarching goal of the COPS field experiment is to advance the quality of forecasts of orographically induced convective precipitation by four-dimensional observations and modeling of its life cycle for identifying the physical and chemical processes responsible for deficiencies in QPF over low-mountain regions. During the COPS field experiment, a GPS network of about 100 GPS stations has been continuously operating during three months in an area of 500 km² in the East of France (Vosges Mountains) and West of Germany (Black Forest). If the mean spacing between the GPS is about 50 km, an East-West GPS profile with a density of about 10 km is dedicated to high resolution tomography. One major goal of the GPS COPS experiment is to validate the GPS tomography with different spatial resolutions. Validation is based on additional radio-soundings and airborne / ground-based LIDAR measurement. The number and the high quality of vertically resolved water vapor observations give an unique data set for GPS tomography validation. Numerous tests have been done on real data to show the type water vapor structures that can be imaging by GPS tomography depending of the assimilation of additional data (radio soundings), the resolution of the tomography grid and the density of GPS network. Finally some applications to different cases studies will be shortly presented.

Beam dynamics validation of the Halbach Technology FFAG Cell for Cornell-BNL Energy Recovery Linac

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

Meot, Francois; Tsoupas, N.; Brooks, S.

The Cornell-BNL Electron Test Accelerator (CBETA), a 150 MeV energy recovery linac (ERL) now in construction at Cornell, employs a fixed-field alternating gradient optics return loop: a single beam line comprised of FFAG cells, which accepts four recirculated energies. CBETA FFAG cell uses Halbach permanent magnet technology, its design studies have covered an extended period of time supported by extensive particle dynamics simulations using computed 3-D field map models. As a result, this approach is discussed, and illustrated here, based on the final stage in these beam dynamics studies, namely the validation of a ultimate, optimized design of the Halbachmore » cell.« less

Beam dynamics validation of the Halbach Technology FFAG Cell for Cornell-BNL Energy Recovery Linac

DOE PAGES

Meot, Francois; Tsoupas, N.; Brooks, S.; ...

2018-04-16

The Cornell-BNL Electron Test Accelerator (CBETA), a 150 MeV energy recovery linac (ERL) now in construction at Cornell, employs a fixed-field alternating gradient optics return loop: a single beam line comprised of FFAG cells, which accepts four recirculated energies. CBETA FFAG cell uses Halbach permanent magnet technology, its design studies have covered an extended period of time supported by extensive particle dynamics simulations using computed 3-D field map models. As a result, this approach is discussed, and illustrated here, based on the final stage in these beam dynamics studies, namely the validation of a ultimate, optimized design of the Halbachmore » cell.« less

Development and validation of an anti-N3 indirect immunofluorescent antibody test to be used as a companion diagnostic test in the framework of a "DIVA" vaccination strategy for avian influenza infections in poultry.

PubMed

Cattoli, Giovanni; Milani, Adelaide; Bettini, Francesca; Serena Beato, Maria; Mancin, Marzia; Terregino, Calogero; Capua, Ilaria

2006-04-01

Avian influenza (AI) infections have become of growing importance both for animal and human health. Vaccination has become a recommended tool to support eradication efforts and limit the economic losses caused by this disease. The "DIVA" system, using a vaccine containing a heterologous neuraminidase to the field virus, has been shown to be an effective tool in increasing the resistance of birds to field challenge, preventing clinical signs and reducing viral shedding in the environment. The companion diagnostic test to the vaccine, however, has been only partially validated in the field against one subtype of neuraminidase (N1). The present paper presents the results of a full laboratory and field validation of the diagnostic test developed to detect antibodies to the N3 subtype of AI in vaccinated and unvaccinated chickens and turkeys. Antibody kinetic studies conducted in the laboratory have shown that antibodies to the N protein may be detected earlier than antibodies to the haemagglutinin. The data derived from this extensive validation trial indicate the excellent capability of this assay in detecting the presence of active AI infection at an early stage in both unvaccinated and vaccinated birds and the lack of interference with vaccine-induced antibodies.

Bioindicators of contaminant exposure and effect in aquatic and terrestrial monitoring

USGS Publications Warehouse

Melancon, Mark J.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

2003-01-01

Bioindicators of contaminant exposure presently used in environmental monitoring arc discussed. Some have been extensively field-validated and arc already in routine application. Included are (1) inhibition of brain or blood cholinesterase by anticholinesterase pesticides, (2) induction of hepatic microsomal cytochromes P450 by chemicals such as PAHs and PCBs, (3) reproductive problems such as terata and eggshell thinning, and (4) aberrations of hemoglobin synthesis, including the effects of lead and of certain chlorinated hydrocarbons. Many studies on DNA damage and of histopathological effects, particularly in the form of tumors, have already been completed. There are presently numerous other opportunities for field validation. Bile metabolites of contaminants in fish reveal exposure to contaminants that might otherwise be difficult to detect or quantify. Bile analysis is beginning to be extended to species other than fishes. Assessment of oxidative damage and immune competence appear to be valuable biomarkers. needing only additional field validation for wider use. The use of metallothioneins as biomarkers depends on the development of convenient, inexpensive methodology that provides information not available from measurements of metal ions. The use of stress proteins as biomarkers depends on development of convenient, inexpensive methodology and field validation. Gene arrays and proteomics hold promise as bioindicators for contaminant exposure or effect, particularly because of the large amount of data that could be generated, but they still need extensive development and testing.

A ferrofluid based energy harvester: Computational modeling, analysis, and experimental validation

NASA Astrophysics Data System (ADS)

Liu, Qi; Alazemi, Saad F.; Daqaq, Mohammed F.; Li, Gang

2018-03-01

A computational model is described and implemented in this work to analyze the performance of a ferrofluid based electromagnetic energy harvester. The energy harvester converts ambient vibratory energy into an electromotive force through a sloshing motion of a ferrofluid. The computational model solves the coupled Maxwell's equations and Navier-Stokes equations for the dynamic behavior of the magnetic field and fluid motion. The model is validated against experimental results for eight different configurations of the system. The validated model is then employed to study the underlying mechanisms that determine the electromotive force of the energy harvester. Furthermore, computational analysis is performed to test the effect of several modeling aspects, such as three-dimensional effect, surface tension, and type of the ferrofluid-magnetic field coupling on the accuracy of the model prediction.

Field Validation of Food Service Listings: A Comparison of Commercial and Online Geographic Information System Databases

PubMed Central

Seliske, Laura; Pickett, William; Bates, Rebecca; Janssen, Ian

2012-01-01

Many studies examining the food retail environment rely on geographic information system (GIS) databases for location information. The purpose of this study was to validate information provided by two GIS databases, comparing the positional accuracy of food service places within a 1 km circular buffer surrounding 34 schools in Ontario, Canada. A commercial database (InfoCanada) and an online database (Yellow Pages) provided the addresses of food service places. Actual locations were measured using a global positioning system (GPS) device. The InfoCanada and Yellow Pages GIS databases provided the locations for 973 and 675 food service places, respectively. Overall, 749 (77.1%) and 595 (88.2%) of these were located in the field. The online database had a higher proportion of food service places found in the field. The GIS locations of 25% of the food service places were located within approximately 15 m of their actual location, 50% were within 25 m, and 75% were within 50 m. This validation study provided a detailed assessment of errors in the measurement of the location of food service places in the two databases. The location information was more accurate for the online database, however, when matching criteria were more conservative, there were no observed differences in error between the databases. PMID:23066385

Field validation of food service listings: a comparison of commercial and online geographic information system databases.

PubMed

Seliske, Laura; Pickett, William; Bates, Rebecca; Janssen, Ian

2012-08-01

Many studies examining the food retail environment rely on geographic information system (GIS) databases for location information. The purpose of this study was to validate information provided by two GIS databases, comparing the positional accuracy of food service places within a 1 km circular buffer surrounding 34 schools in Ontario, Canada. A commercial database (InfoCanada) and an online database (Yellow Pages) provided the addresses of food service places. Actual locations were measured using a global positioning system (GPS) device. The InfoCanada and Yellow Pages GIS databases provided the locations for 973 and 675 food service places, respectively. Overall, 749 (77.1%) and 595 (88.2%) of these were located in the field. The online database had a higher proportion of food service places found in the field. The GIS locations of 25% of the food service places were located within approximately 15 m of their actual location, 50% were within 25 m, and 75% were within 50 m. This validation study provided a detailed assessment of errors in the measurement of the location of food service places in the two databases. The location information was more accurate for the online database, however, when matching criteria were more conservative, there were no observed differences in error between the databases.

Current progress in patient-specific modeling

PubMed Central

2010-01-01

We present a survey of recent advancements in the emerging field of patient-specific modeling (PSM). Researchers in this field are currently simulating a wide variety of tissue and organ dynamics to address challenges in various clinical domains. The majority of this research employs three-dimensional, image-based modeling techniques. Recent PSM publications mostly represent feasibility or preliminary validation studies on modeling technologies, and these systems will require further clinical validation and usability testing before they can become a standard of care. We anticipate that with further testing and research, PSM-derived technologies will eventually become valuable, versatile clinical tools. PMID:19955236

Molecular hydrodynamics: Vortex formation and sound wave propagation

DOE PAGES

Han, Kyeong Hwan; Kim, Changho; Talkner, Peter; ...

2018-01-14

In the present study, quantitative feasibility tests of the hydrodynamic description of a two-dimensional fluid at the molecular level are performed, both with respect to length and time scales. Using high-resolution fluid velocity data obtained from extensive molecular dynamics simulations, we computed the transverse and longitudinal components of the velocity field by the Helmholtz decomposition and compared them with those obtained from the linearized Navier-Stokes (LNS) equations with time-dependent transport coefficients. By investigating the vortex dynamics and the sound wave propagation in terms of these field components, we confirm the validity of the LNS description for times comparable to ormore » larger than several mean collision times. The LNS description still reproduces the transverse velocity field accurately at smaller times, but it fails to predict characteristic patterns of molecular origin visible in the longitudinal velocity field. Based on these observations, we validate the main assumptions of the mode-coupling approach. The assumption that the velocity autocorrelation function can be expressed in terms of the fluid velocity field and the tagged particle distribution is found to be remarkably accurate even for times comparable to or smaller than the mean collision time. This suggests that the hydrodynamic-mode description remains valid down to the molecular scale.« less

Molecular hydrodynamics: Vortex formation and sound wave propagation

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

Han, Kyeong Hwan; Kim, Changho; Talkner, Peter

In the present study, quantitative feasibility tests of the hydrodynamic description of a two-dimensional fluid at the molecular level are performed, both with respect to length and time scales. Using high-resolution fluid velocity data obtained from extensive molecular dynamics simulations, we computed the transverse and longitudinal components of the velocity field by the Helmholtz decomposition and compared them with those obtained from the linearized Navier-Stokes (LNS) equations with time-dependent transport coefficients. By investigating the vortex dynamics and the sound wave propagation in terms of these field components, we confirm the validity of the LNS description for times comparable to ormore » larger than several mean collision times. The LNS description still reproduces the transverse velocity field accurately at smaller times, but it fails to predict characteristic patterns of molecular origin visible in the longitudinal velocity field. Based on these observations, we validate the main assumptions of the mode-coupling approach. The assumption that the velocity autocorrelation function can be expressed in terms of the fluid velocity field and the tagged particle distribution is found to be remarkably accurate even for times comparable to or smaller than the mean collision time. This suggests that the hydrodynamic-mode description remains valid down to the molecular scale.« less

Three DIBELS Tasks vs. Three Informal Reading/Spelling Tasks: A Comparison of Predictive Validity

ERIC Educational Resources Information Center

Morris, Darrell; Trathen, Woodrow; Perney, Jan; Gill, Tom; Schlagal, Robert; Ward, Devery; Frye, Elizabeth M.

2017-01-01

Within a developmental framework, this study compared the predictive validity of three DIBELS tasks (phoneme segmentation fluency [PSF], nonsense word fluency [NWF], and oral reading fluency [ORF]) with that of three alternative tasks drawn from the field of reading (phonemic spelling [phSPEL], word recognition-timed [WR-t], and graded passage…

Field-scale moisture estimates using COSMOS sensors: a validation study with temporary networks and leaf-area-indices

USDA-ARS?s Scientific Manuscript database

The Cosmic-ray Soil Moisture Observing System (COSMOS) is a new and innovative method for estimating surface and near surface soil moisture at large (~700 m) scales. This system accounts for liquid water within its measurement volume. Many of the sites used in the early validation of the system had...

A Replication of the Internal Validity Structure of Three Major Teaching Rating Scales

ERIC Educational Resources Information Center

Peters, Scott J.; Pereira, Nielsen

2017-01-01

Even as the importance of replication research has become more widely understood, the field of gifted education is almost completely devoid of replication studies. An area in which replication is a particular problem is in student identification research, since instrument validity is a necessary prerequisite for any sound psychometric decision. To…

Predictive Validity and Impact of CAEP Standard 3.2: Results from One Master's-Level Teacher Preparation Program

ERIC Educational Resources Information Center

Evans, Carla M.

2017-01-01

This study investigates the predictive validity and policy impact of Council for Accreditation of Educator Preparation minimum admission requirements in Standard 3.2 on teacher preparation programs (TPPs), their applicants, and the broader field of educator preparation. Undergraduate grade point average (GPA) and Graduate Record Examination (GRE)…

Development and Field Test of the Multiple Intelligences Learning Instruction Congruency Impact Scale

ERIC Educational Resources Information Center

Peifer, Nancy

2012-01-01

The purpose of this study was to contribute to the academic discussion regarding the validity of Multiple Intelligences (MI) theory through focusing on the validity of an important construct embedded in the theory, that of congruence between instructional style and preferred MI style for optimal learning. Currently there is insufficient empirical…

Development of a Self-Efficacy Scale toward Piano Lessons

ERIC Educational Resources Information Center

Kurtuldu, M. Kayhan; Bulut, Damla

2017-01-01

This study aimed to develop a valid and reliable scale to determine students' levels of self-efficacy toward piano lessons. The sample consisted of 456 university-level piano students enrolled in Music Education programs. Experts in language and the field of music were consulted to establish content validity of the items included in the scalar…

Developing and Validating Field Measurement Scales for Absorptive Capacity and Experienced Community of Practice

ERIC Educational Resources Information Center

Cadiz, David; Sawyer, John E.; Griffith, Terri L.

2009-01-01

Research on knowledge transfer in organizations has been hampered by the lack of tools yielding valid scores for studying critical constructs in concert. The authors developed survey measures of absorptive capacity (the ability to transform new knowledge into usable knowledge) and experienced community of practice (the extent to which a person is…

"Is There an Equal (Amount of) Juice?" Exploring the Repeated Question Effect in Conservation through Conversation

ERIC Educational Resources Information Center

Baucal, Aleksandar; Arcidiacono, Francesco; Budjevac, Nevena

2013-01-01

The aim of this paper is to highlight and discuss advantages and constraints of different methods applied within the field of children's thinking studies, through the test of the repeated question hypothesis validity, using the conservation of liquid task. In our perspective, the Piagetian interview is an ecologically valid context for…

Validation of Metagenomic Next-Generation Sequencing Tests for Universal Pathogen Detection.

PubMed

Schlaberg, Robert; Chiu, Charles Y; Miller, Steve; Procop, Gary W; Weinstock, George

2017-06-01

- Metagenomic sequencing can be used for detection of any pathogens using unbiased, shotgun next-generation sequencing (NGS), without the need for sequence-specific amplification. Proof-of-concept has been demonstrated in infectious disease outbreaks of unknown causes and in patients with suspected infections but negative results for conventional tests. Metagenomic NGS tests hold great promise to improve infectious disease diagnostics, especially in immunocompromised and critically ill patients. - To discuss challenges and provide example solutions for validating metagenomic pathogen detection tests in clinical laboratories. A summary of current regulatory requirements, largely based on prior guidance for NGS testing in constitutional genetics and oncology, is provided. - Examples from 2 separate validation studies are provided for steps from assay design, and validation of wet bench and bioinformatics protocols, to quality control and assurance. - Although laboratory and data analysis workflows are still complex, metagenomic NGS tests for infectious diseases are increasingly being validated in clinical laboratories. Many parallels exist to NGS tests in other fields. Nevertheless, specimen preparation, rapidly evolving data analysis algorithms, and incomplete reference sequence databases are idiosyncratic to the field of microbiology and often overlooked.

Probabilistic approach of resource assessment in Kerinci geothermal field using numerical simulation coupling with monte carlo simulation

NASA Astrophysics Data System (ADS)

Hidayat, Iki; Sutopo; Pratama, Heru Berian

2017-12-01

The Kerinci geothermal field is one phase liquid reservoir system in the Kerinci District, western part of Jambi Province. In this field, there are geothermal prospects that identified by the heat source up flow inside a National Park area. Kerinci field was planned to develop 1×55 MWe by Pertamina Geothermal Energy. To define reservoir characterization, the numerical simulation of Kerinci field is developed by using TOUGH2 software with information from conceptual model. The pressure and temperature profile well data of KRC-B1 are validated with simulation data to reach natural state condition. The result of the validation is suitable matching. Based on natural state simulation, the resource assessment of Kerinci geothermal field is estimated by using Monte Carlo simulation with the result P10-P50-P90 are 49.4 MW, 64.3 MW and 82.4 MW respectively. This paper is the first study of resource assessment that has been estimated successfully in Kerinci Geothermal Field using numerical simulation coupling with Monte carlo simulation.

Validation of an inertial measurement unit for the measurement of jump count and height.

PubMed

MacDonald, Kerry; Bahr, Roald; Baltich, Jennifer; Whittaker, Jackie L; Meeuwisse, Willem H

2017-05-01

To validate the use of an inertial measurement unit (IMU) for the collection of total jump count and assess the validity of an IMU for the measurement of jump height against 3-D motion analysis. Cross sectional validation study. 3D motion-capture laboratory and field based settings. Thirteen elite adolescent volleyball players. Participants performed structured drills, played a 4 set volleyball match and performed twelve counter movement jumps. Jump counts from structured drills and match play were validated against visual count from recorded video. Jump height during the counter movement jumps was validated against concurrent 3-D motion-capture data. The IMU device captured more total jumps (1032) than visual inspection (977) during match play. During structured practice, device jump count sensitivity was strong (96.8%) while specificity was perfect (100%). The IMU underestimated jump height compared to 3D motion-capture with mean differences for maximal and submaximal jumps of 2.5 cm (95%CI: 1.3 to 3.8) and 4.1 cm (3.1-5.1), respectively. The IMU offers a valid measuring tool for jump count. Although the IMU underestimates maximal and submaximal jump height, our findings demonstrate its practical utility for field-based measurement of jump load. Copyright © 2016 Elsevier Ltd. All rights reserved.

Coaxial cable sensors and sensing instrument for crack detection in bridge structures--phase I : field qualification/validation planning.

DOT National Transportation Integrated Search

2009-11-01

The objectives of this study are to pre-test analyze a decommissioned reinforced concrete (RC) bridge that is selected in consultation with the New York State Department of Transportation (NYSDOT), and design and plan the field tests of the bridge fo...

Comprehensive Cocurricular Support Promotes Persistence of Community College STEM Students

ERIC Educational Resources Information Center

Shadduck, Peggy

2017-01-01

Despite good career prospects in science, technology, engineering, and mathematics (STEM) fields, persistence of students in STEM fields of study at the community college and transfer to universities to pursue STEM majors is often quite low. Theories of persistence emphasize the importance of engagement, integration, validation, and financial…

Modeling the Effects of Conservation Tillage on Water Quality at the Field Scale

USDA-ARS?s Scientific Manuscript database

The development and application of predictive tools to quantitatively assess the effects of tillage and related management activities should be carefully tested against high quality field data. This study reports on: 1) the calibration and validation of the Root Zone Water Quality Model (RZWQM) to a...

Emotion in Teaching and Learning: Development and Validation of the Classroom Emotions Scale

ERIC Educational Resources Information Center

Titsworth, Scott; Quinlan, Margaret M.; Mazer, Joseph P.

2010-01-01

Although scholars from across the field of communication have highlighted the importance of emotion in interpersonal relationships, persuasive messages, and organizations, the topic has yet to receive systematic attention from scholars who study classroom communication. Using interdisciplinary literature from communication and other fields as a…

SU-F-T-369: Validation of Monte-Carlo Beam Model for a Range of Small Fields in Heterogeneous Medium - A Measurement Based Study

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

Karthikeyan, N; Bharathiya University, Coimbatore, Tamilnadu; Ganesh, KM

Purpose: To validate the Monaco montecorlo beam model for a range of small field in the heterogeneous medium. Methods: A in-house phantom with three different medium of Foam, PMMA and derlin resembling the densities of lung, soft tissue, and bone was used for the study. The field sizes of 8, 16, 24, 32 and 48mm were studied for the validation of montecarlo algorithm using 0.01cc volume ionchamber and gafchromic films. The 6MV photon beam from Elekta Beam modulator was used with 100cm SAD setup. The outputs were measured at the depth of 5, 10 and 20mm in every second mediummore » with 3cm buildup of first medium for the interface of lung-bone, lung-soft tissue, soft tissue-bone, bone-lung and soft tissue-lung. Similarly, the 2D dose analysis with gamma criteria of 2%2mm were done at the same depths using gafchromic film. For all the measurements 10.4×10.4cm were taken as reference to which the other field sizes were compared. Monaco TPSv.3.20 was used to calculate the dose distribution for all the simulated measurement setups. Results: The average maximum difference among the field sizes of 8, 16, 24, 32 and 48mm at the depth of 5mm in second medium with the interface of lung-bone, lung-soft tissue, soft tissue-bone, bone-lung and soft tissue-lung were observed as 1.29±0.14%, 0.49±0.16%, 0.87±0.23%, 0.92±0.11%, 1.01±0.19% respectively. The minimum and maximum variation of dose among different materials for the smallest field size of 8mm were observed as 0.23% and 1.67% respectively. The 2D analysis showed the average gamma passing of 98.9±0.5%. The calculated two-tailed P-value were showed insignificance with values of 0.562 and 0.452 for both ionchamber and film measurements. Conclusion: The accuracy of dose calculation for the small fields in Monaco Montecarlo TPS algorithm was validated in different inhomogeneous medium and found the results were well correlated with measurement data.« less

Environmental Validation of Legionella Control in a VHA Facility Water System.

PubMed

Jinadatha, Chetan; Stock, Eileen M; Miller, Steve E; McCoy, William F

2018-03-01

OBJECTIVES We conducted this study to determine what sample volume, concentration, and limit of detection (LOD) are adequate for environmental validation of Legionella control. We also sought to determine whether time required to obtain culture results can be reduced compared to spread-plate culture method. We also assessed whether polymerase chain reaction (PCR) and in-field total heterotrophic aerobic bacteria (THAB) counts are reliable indicators of Legionella in water samples from buildings. DESIGN Comparative Legionella screening and diagnostics study for environmental validation of a healthcare building water system. SETTING Veterans Health Administration (VHA) facility water system in central Texas. METHODS We analyzed 50 water samples (26 hot, 24 cold) from 40 sinks and 10 showers using spread-plate cultures (International Standards Organization [ISO] 11731) on samples shipped overnight to the analytical lab. In-field, on-site cultures were obtained using the PVT (Phigenics Validation Test) culture dipslide-format sampler. A PCR assay for genus-level Legionella was performed on every sample. RESULTS No practical differences regardless of sample volume filtered were observed. Larger sample volumes yielded more detections of Legionella. No statistically significant differences at the 1 colony-forming unit (CFU)/mL or 10 CFU/mL LOD were observed. Approximately 75% less time was required when cultures were started in the field. The PCR results provided an early warning, which was confirmed by spread-plate cultures. The THAB results did not correlate with Legionella status. CONCLUSIONS For environmental validation at this facility, we confirmed that (1) 100 mL sample volumes were adequate, (2) 10× concentrations were adequate, (3) 10 CFU/mL LOD was adequate, (4) in-field cultures reliably reduced time to get results by 75%, (5) PCR provided a reliable early warning, and (6) THAB was not predictive of Legionella results. Infect Control Hosp Epidemiol 2018;39:259-266.

The creation and validation of an instrument to measure school STEM Culture

NASA Astrophysics Data System (ADS)

White, Christopher

Although current research exists on school culture, there is a gap in the literature on specialized aspects of culture such as STEM Culture defined as the beliefs, values, practices, resources, and challenges in STEM fields (Science, Technology, Engineering and Mathematics) within a school. The objective of this study was to create a valid and reliable instrument, the STEM Culture Assessment Tool (STEM-CAT), that measures this cultural aspect based on a survey of stakeholder groups within the school community and use empirical data to support the use of this instrument to measure STEM Culture. Items were created and face validity was determined through a focus group and expert review before a pilot study was conducted to determine reliability of the items. Once items were determined reliable, the survey was given to eight high schools and results were correlated to the percentage of seniors who self-reported whether they intend to pursue STEM fields upon graduation. The results of this study indicate further need for research to determine how the STEM-CAT correlates to STEM culture due to some inconsistencies with the dependent variable in this study. Future research could be done correlating the results of the STEM-CAT with participation in Advanced Placement science and mathematics, SAT/ACT scores in science and mathematics or the number of students who actually pursue STEM fields rather than a prediction halfway through the 12th grade.

Motion-induced eddy current thermography for high-speed inspection

NASA Astrophysics Data System (ADS)

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

2017-08-01

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

3D-quantitative structure-activity relationship studies on benzothiadiazepine hydroxamates as inhibitors of tumor necrosis factor-alpha converting enzyme.

PubMed

Murumkar, Prashant R; Giridhar, Rajani; Yadav, Mange Ram

2008-04-01

A set of 29 benzothiadiazepine hydroxamates having selective tumor necrosis factor-alpha converting enzyme inhibitory activity were used to compare the quality and predictive power of 3D-quantitative structure-activity relationship, comparative molecular field analysis, and comparative molecular similarity indices models for the atom-based, centroid/atom-based, data-based, and docked conformer-based alignment. Removal of two outliers from the initial training set of molecules improved the predictivity of models. Among the 3D-quantitative structure-activity relationship models developed using the above four alignments, the database alignment provided the optimal predictive comparative molecular field analysis model for the training set with cross-validated r(2) (q(2)) = 0.510, non-cross-validated r(2) = 0.972, standard error of estimates (s) = 0.098, and F = 215.44 and the optimal comparative molecular similarity indices model with cross-validated r(2) (q(2)) = 0.556, non-cross-validated r(2) = 0.946, standard error of estimates (s) = 0.163, and F = 99.785. These models also showed the best test set prediction for six compounds with predictive r(2) values of 0.460 and 0.535, respectively. The contour maps obtained from 3D-quantitative structure-activity relationship studies were appraised for activity trends for the molecules analyzed. The comparative molecular similarity indices models exhibited good external predictivity as compared with that of comparative molecular field analysis models. The data generated from the present study helped us to further design and report some novel and potent tumor necrosis factor-alpha converting enzyme inhibitors.

Validation of a Previously Developed Geospatial Model That Predicts the Prevalence of Listeria monocytogenes in New York State Produce Fields

PubMed Central

Weller, Daniel; Shiwakoti, Suvash; Bergholz, Peter; Grohn, Yrjo; Wiedmann, Martin

2015-01-01

Technological advancements, particularly in the field of geographic information systems (GIS), have made it possible to predict the likelihood of foodborne pathogen contamination in produce production environments using geospatial models. Yet, few studies have examined the validity and robustness of such models. This study was performed to test and refine the rules associated with a previously developed geospatial model that predicts the prevalence of Listeria monocytogenes in produce farms in New York State (NYS). Produce fields for each of four enrolled produce farms were categorized into areas of high or low predicted L. monocytogenes prevalence using rules based on a field's available water storage (AWS) and its proximity to water, impervious cover, and pastures. Drag swabs (n = 1,056) were collected from plots assigned to each risk category. Logistic regression, which tested the ability of each rule to accurately predict the prevalence of L. monocytogenes, validated the rules based on water and pasture. Samples collected near water (odds ratio [OR], 3.0) and pasture (OR, 2.9) showed a significantly increased likelihood of L. monocytogenes isolation compared to that for samples collected far from water and pasture. Generalized linear mixed models identified additional land cover factors associated with an increased likelihood of L. monocytogenes isolation, such as proximity to wetlands. These findings validated a subset of previously developed rules that predict L. monocytogenes prevalence in produce production environments. This suggests that GIS and geospatial models can be used to accurately predict L. monocytogenes prevalence on farms and can be used prospectively to minimize the risk of preharvest contamination of produce. PMID:26590280

Tobacco Use Prevention for the Young (TUPY-S): Development, Validity and Reliability of an Interactive Multimedia Strategy from the Adolescents’ Perspective in Malaysia

PubMed Central

Zin, Faridah Mohd; Hillaluddin, Azlin Hilma; Mustaffa, Jamaludin

2017-01-01

Objective: This study aims to develop, validate and determine the reliability of an interactive multimedia strategy to prevent tobacco use among the young (TUPY-S) from an adolescents’ perspective. Methods: A descriptive study design was utilized. A modular instruction guideline by Russel (1974) was followed in the entire process, comprising a feasibility study, a review of existing modules, specification of the objectives, identification of the construct criterion items, learner analysis and entry behavior specification, establishment of the sequence instruction and media selection, a tryout with students and a field test. Result: Feasibility was agreed among the researchers and the school authorities. Culturally suitable rigorously developed tobacco use preventive strategies delivered using information technology (IT) are lacking in the literature. The objective of TUPY-S is to prevent tobacco use among adolescents living in Malaysia. Identified construct criterion items include knowledge, attitude, intention to use, self-efficacy, and refusal skill. The target population was early adolescents belonging to generation-Z. Content was developed from the adolescents’ perspective and delivered using IT in Malay language. Content validity, assessed by six experts in the field and module development, was good at 86%. The students’ tryout showed satisfactory face validity subjectively and objectively (85.5%) and high alpha Cronbach reliability (0.91). Conclusion: TUPY-S was confirmed to suit early adolescents of the current generation living in Malaysia. It demonstrated good content validity among the experts, satisfactory face validity and reliability among the target population. TUPY-S is ready to be evaluated for its effectiveness among early adolescents. PMID:28612599

The Servant Leadership Survey: Development and Validation of a Multidimensional Measure.

PubMed

van Dierendonck, Dirk; Nuijten, Inge

2011-09-01

PURPOSE: The purpose of this paper is to describe the development and validation of a multi-dimensional instrument to measure servant leadership. DESIGN/METHODOLOGY/APPROACH: Based on an extensive literature review and expert judgment, 99 items were formulated. In three steps, using eight samples totaling 1571 persons from The Netherlands and the UK with a diverse occupational background, a combined exploratory and confirmatory factor analysis approach was used. This was followed by an analysis of the criterion-related validity. FINDINGS: The final result is an eight-dimensional measure of 30 items: the eight dimensions being: standing back, forgiveness, courage, empowerment, accountability, authenticity, humility, and stewardship. The internal consistency of the subscales is good. The results show that the Servant Leadership Survey (SLS) has convergent validity with other leadership measures, and also adds unique elements to the leadership field. Evidence for criterion-related validity came from studies relating the eight dimensions to well-being and performance. IMPLICATIONS: With this survey, a valid and reliable instrument to measure the essential elements of servant leadership has been introduced. ORIGINALITY/VALUE: The SLS is the first measure where the underlying factor structure was developed and confirmed across several field studies in two countries. It can be used in future studies to test the underlying premises of servant leadership theory. The SLS provides a clear picture of the key servant leadership qualities and shows where improvements can be made on the individual and organizational level; as such, it may also offer a valuable starting point for training and leadership development.

Risk perception and information processing: the development and validation of a questionnaire to assess self-reported information processing.

PubMed

Smerecnik, Chris M R; Mesters, Ilse; Candel, Math J J M; De Vries, Hein; De Vries, Nanne K

2012-01-01

The role of information processing in understanding people's responses to risk information has recently received substantial attention. One limitation of this research concerns the unavailability of a validated questionnaire of information processing. This article presents two studies in which we describe the development and validation of the Information-Processing Questionnaire to meet that need. Study 1 describes the development and initial validation of the questionnaire. Participants were randomized to either a systematic processing or a heuristic processing condition after which they completed a manipulation check and the initial 15-item questionnaire and again two weeks later. The questionnaire was subjected to factor reliability and validity analyses on both measurement times for purposes of cross-validation of the results. A two-factor solution was observed representing a systematic processing and a heuristic processing subscale. The resulting scale showed good reliability and validity, with the systematic condition scoring significantly higher on the systematic subscale and the heuristic processing condition significantly higher on the heuristic subscale. Study 2 sought to further validate the questionnaire in a field study. Results of the second study corresponded with those of Study 1 and provided further evidence of the validity of the Information-Processing Questionnaire. The availability of this information-processing scale will be a valuable asset for future research and may provide researchers with new research opportunities. © 2011 Society for Risk Analysis.

An Engineering Method of Civil Jet Requirements Validation Based on Requirements Project Principle

NASA Astrophysics Data System (ADS)

Wang, Yue; Gao, Dan; Mao, Xuming

2018-03-01

A method of requirements validation is developed and defined to meet the needs of civil jet requirements validation in product development. Based on requirements project principle, this method will not affect the conventional design elements, and can effectively connect the requirements with design. It realizes the modern civil jet development concept, which is “requirement is the origin, design is the basis”. So far, the method has been successfully applied in civil jet aircraft development in China. Taking takeoff field length as an example, the validation process and the validation method of the requirements are detailed introduced in the study, with the hope of providing the experiences to other civil jet product design.

Independent validation of Swarm Level 2 magnetic field products and `Quick Look' for Level 1b data

NASA Astrophysics Data System (ADS)

Beggan, Ciarán D.; Macmillan, Susan; Hamilton, Brian; Thomson, Alan W. P.

2013-11-01

Magnetic field models are produced on behalf of the European Space Agency (ESA) by an independent scientific consortium known as the Swarm Satellite Constellation Application and Research Facility (SCARF), through the Level 2 Processor (L2PS). The consortium primarily produces magnetic field models for the core, lithosphere, ionosphere and magnetosphere. Typically, for each magnetic product, two magnetic field models are produced in separate chains using complementary data selection and processing techniques. Hence, the magnetic field models from the complementary processing chains will be similar but not identical. The final step in the overall L2PS therefore involves inspection and validation of the magnetic field models against each other and against data from (semi-) independent sources (e.g. ground observatories). We describe the validation steps for each magnetic field product and the comparison against independent datasets, and we show examples of the output of the validation. In addition, the L2PS also produces a daily set of `Quick Look' output graphics and statistics to monitor the overall quality of Level 1b data issued by ESA. We describe the outputs of the `Quick Look' chain.

Experimental Study of Impinging Jets Flow-Fields

DTIC Science & Technology

2016-07-27

1 Grant # N000141410830 Experimental Study of Impinging Jet Flow-Fields Final Report for Period: Jun 15, 2014 – Jun 14, 2016 PI: Dennis K...impinging jet model in the absence of any jet heating. The results of the computations had been compared with the experimental data produced in the...of the validity of the computations, and also of the experimental approach. Figure 12a. Initial single

Evidences of Validity of a Scale for Mapping Professional as Defining Competences and Performance by Brazilian Tutors

ERIC Educational Resources Information Center

Coelho, Francisco Antonio, Jr.; Ferreira, Rodrigo Rezende; Paschoal, Tatiane; Faiad, Cristiane; Meneses, Paulo Murce

2015-01-01

The purpose of this study was twofold: to assess evidences of construct validity of the Brazilian Scale of Tutors Competences in the field of Open and Distance Learning and to examine if variables such as professional experience, perception of the student´s learning performance and prior experience influence the development of technical and…

Psychometric Properties of Eating Disorder Instruments in Black and White Young Women: Internal Consistency, Temporal Stability, and Validity

ERIC Educational Resources Information Center

Bardone-Cone, Anna M.; Boyd, Clarissa A.

2007-01-01

Most of the major instruments in the eating disorder field have documented psychometric support only in predominantly White samples. The current study examined the internal consistency, temporal stability, and convergent and discriminant validity of a variety of eating disorder measures in Black (n = 97) and White (n = 179) female undergraduates.…

Integrating the Analysis of Mental Operations into Multilevel Models to Validate an Assessment of Higher Education Students' Competency in Business and Economics

ERIC Educational Resources Information Center

Brückner, Sebastian; Pellegrino, James W.

2016-01-01

The Standards for Educational and Psychological Testing indicate that validation of assessments should include analyses of participants' response processes. However, such analyses typically are conducted only to supplement quantitative field studies with qualitative data, and seldom are such data connected to quantitative data on student or item…

Initial Validation of the Chinese Quality of Life Questionnaire-Intellectual Disabilities (CQOL-ID): A Cultural Perspective

ERIC Educational Resources Information Center

Wong, P. K. S.; Wong, D. F. K.; Schalock, R. L.; Chou, Y-C.

2011-01-01

Background: In the field of intellectual disabilities (ID), the quality of life concept has been developing rapidly in Chinese societies including Hong Kong, mainland China and Taiwan. However, there is a lack of locally validated instruments to measure the quality of life of people with ID. The study reported in this paper attempted to validate…

Examining Underlying Relationships between the Supports Intensity Scale-Adult Version and the Supports Intensity Scale-Children's Version

ERIC Educational Resources Information Center

Seo, Hyojeong; Wehmeyer, Michael L.; Shogren, Karrie A.; Hughes, Carolyn; Thompson, James R.; Little, Todd D.; Palmer, Susan B.

2017-01-01

Given the growing importance of support needs assessment in the field of intellectual disability, it is imperative to develop assessments of support needs whose scores and inferences demonstrate reliability and validity. The purpose of this study was to examine the criterion validity of scores on the "Supports Intensity Scale-Children's…

Standardization of Distant Intercessory Prayer for Research on Health and Well-Being

ERIC Educational Resources Information Center

Parkinson, Kathleen Elizabeth

2007-01-01

In recent years, distant (remote) intercessory prayer has been put up against the scientific method of research. Studies are few, variable, and tend to be nongeneralizable. Lack of construct validity of the variable prayer is one of the weaknesses that opens up the research to valid critique and scrutiny. The belief that research in this field is…

Studying Sexual Aggression: A Review of the Evolution and Validity of Laboratory Paradigms

PubMed Central

Davis, Kelly Cue; George, William H.; Nagayama Hall, Gordon C.; Parrott, Dominic J.; Tharp, Andra Teten; Stappenbeck, Cynthia A.

2018-01-01

Objective Researchers have endeavored for decades to develop and implement experimental assessments of sexual aggression and its precursors to capitalize on the many scientific advantages offered by laboratory experiments, such as rigorous control of key variables and identification of causal relationships. The purpose of this review is to provide an overview of and commentary on the evolution of these laboratory-based methods. Conclusions To date, two primary types of sexual aggression laboratory studies have been developed: those that involve behavioral analogues of sexual aggression and those that assess postulated precursors to sexually aggressive behavior. Although the study of sexual aggression in the laboratory is fraught with methodological challenges, validity concerns, and ethical considerations, advances in the field have resulted in greater methodological rigor, more precise dependent measures, and improved experimental validity, reliability, and realism. Because highly effective sexual aggression prevention strategies remain elusive, continued laboratory-based investigation of sexual aggression coupled with translation of critical findings to the development and modification of sexual aggression prevention programs remains an important task for the field. PMID:29675289

All-sky photogrammetry techniques to georeference a cloud field

NASA Astrophysics Data System (ADS)

Crispel, Pierre; Roberts, Gregory

2018-01-01

In this study, we present a novel method of identifying and geolocalizing cloud field elements from a portable all-sky camera stereo network based on the ground and oriented towards zenith. The methodology is mainly based on stereophotogrammetry which is a 3-D reconstruction technique based on triangulation from corresponding stereo pixels in rectified images. In cases where clouds are horizontally separated, identifying individual positions is performed with segmentation techniques based on hue filtering and contour detection algorithms. Macroscopic cloud field characteristics such as cloud layer base heights and velocity fields are also deduced. In addition, the methodology is fitted to the context of measurement campaigns which impose simplicity of implementation, auto-calibration, and portability. Camera internal geometry models are achieved a priori in the laboratory and validated to ensure a certain accuracy in the peripheral parts of the all-sky image. Then, stereophotogrammetry with dense 3-D reconstruction is applied with cameras spaced 150 m apart for two validation cases. The first validation case is carried out with cumulus clouds having a cloud base height at 1500 m a.g.l. The second validation case is carried out with two cloud layers: a cumulus fractus layer with a base height at 1000 m a.g.l. and an altocumulus stratiformis layer with a base height of 2300 m a.g.l. Velocity fields at cloud base are computed by tracking image rectangular patterns through successive shots. The height uncertainty is estimated by comparison with a Vaisala CL31 ceilometer located on the site. The uncertainty on the horizontal coordinates and on the velocity field are theoretically quantified by using the experimental uncertainties of the cloud base height and camera orientation. In the first cumulus case, segmentation of the image is performed to identify individuals clouds in the cloud field and determine the horizontal positions of the cloud centers.

Assessments on GOCE-based Gravity Field Model Comparisons with Terrestrial Data Using Wavelet Decomposition and Spectral Enhancement Approaches

NASA Astrophysics Data System (ADS)

Erol, Serdar; Serkan Isık, Mustafa; Erol, Bihter

2016-04-01

The recent Earth gravity field satellite missions data lead significant improvement in Global Geopotential Models in terms of both accuracy and resolution. However the improvement in accuracy is not the same everywhere in the Earth and therefore quantifying the level of improvement locally is necessary using the independent data. The validations of the level-3 products from the gravity field satellite missions, independently from the estimation procedures of these products, are possible using various arbitrary data sets, as such the terrestrial gravity observations, astrogeodetic vertical deflections, GPS/leveling data, the stationary sea surface topography. Quantifying the quality of the gravity field functionals via recent products has significant importance for determination of the regional geoid modeling, base on the satellite and terrestrial data fusion with an optimal algorithm, beside the statistical reporting the improvement rates depending on spatial location. In the validations, the errors and the systematic differences between the data and varying spectral content of the compared signals should be considered in order to have comparable results. In this manner this study compares the performance of Wavelet decomposition and spectral enhancement techniques in validation of the GOCE/GRACE based Earth gravity field models using GPS/leveling and terrestrial gravity data in Turkey. The terrestrial validation data are filtered using Wavelet decomposition technique and the numerical results from varying levels of decomposition are compared with the results which are derived using the spectral enhancement approach with contribution of an ultra-high resolution Earth gravity field model. The tests include the GO-DIR-R5, GO-TIM-R5, GOCO05S, EIGEN-6C4 and EGM2008 global models. The conclusion discuss the superiority and drawbacks of both concepts as well as reporting the performance of tested gravity field models with an estimate of their contribution to modeling the geoid in Turkish territory.

Coaxial cable sensors and sensing instrument for crack detection in bridge structures--phase I : field qualification/validation planning : final report.

DOT National Transportation Integrated Search

2009-11-06

The objectives of this study are to pre-test analyze a decommissioned RC bridge that is selected in consultation : with New York State Department of Transportation (NYSDOT), and design and plan the field tests of the bridge : for the performance qual...

Adaptations of the Saker-Solomons test: simple, reliable colorimetric field assays for chloroquine and its metabolites in urine.

PubMed

Mount, D L; Nahlen, B L; Patchen, L C; Churchill, F C

1989-01-01

Two field-adapted colorimetric methods for measuring the antimalarial drug chloroquine in urine are described. Both are modifications of the method of Saker and Solomons for screening urine for phencyclidine and other drugs of abuse, using the colour reagent tetrabromophenolphthalein ethyl ester. One method is semiquantitative, detecting the presence of chloroquine (Cq) and its metabolites in urine with a 1 microgram/ml detection limit; it is more sensitive and reliable than the commonly used Dill-Glazko method and is as easy to apply in the field. The second method uses a hand-held, battery-operated filter photometer to quantify Cq and its metabolites with a 2 microgram/ml detection limit and a linear range up to 8 micrograms/ml. The first method was validated in the field using a published quantitative colorimetric method and samples from a malaria study in Nigeria. The second method was validated in the laboratory against high-performance liquid chromatographic results on paired samples from the Nigerian study. Both methods may be used in remote locations where malaria is endemic and no electricity is available.

Systematic review and proposal of a field-based physical fitness-test battery in preschool children: the PREFIT battery.

PubMed

Ortega, Francisco B; Cadenas-Sánchez, Cristina; Sánchez-Delgado, Guillermo; Mora-González, José; Martínez-Téllez, Borja; Artero, Enrique G; Castro-Piñero, Jose; Labayen, Idoia; Chillón, Palma; Löf, Marie; Ruiz, Jonatan R

2015-04-01

Physical fitness is a powerful health marker in childhood and adolescence, and it is reasonable to think that it might be just as important in younger children, i.e. preschoolers. At the moment, researchers, clinicians and sport practitioners do not have enough information about which fitness tests are more reliable, valid and informative from the health point of view to be implemented in preschool children. Our aim was to systematically review the studies conducted in preschool children using field-based fitness tests, and examine their (1) reliability, (2) validity, and (3) relationship with health outcomes. Our ultimate goal was to propose a field-based physical fitness-test battery to be used in preschool children. PubMed and Web of Science. Studies conducted in healthy preschool children that included field-based fitness tests. When using PubMed, we included Medical Subject Heading (MeSH) terms to enhance the power of the search. A set of fitness-related terms were combined with 'child, preschool' [MeSH]. The same strategy and terms were used for Web of Science (except for the MeSH option). Since no previous reviews with a similar aim were identified, we searched for all articles published up to 1 April 2014 (no starting date). A total of 2,109 articles were identified, of which 22 articles were finally selected for this review. Most studies focused on reliability of the fitness tests (n = 21, 96%), while very few focused on validity (0 criterion-related validity and 4 (18%) convergent validity) or relationship with health outcomes (0 longitudinal and 1 (5%) cross-sectional study). Motor fitness, particularly balance, was the most studied fitness component, while cardiorespiratory fitness was the least studied. After analyzing the information retrieved in the current systematic review about fitness testing in preschool children, we propose the PREFIT battery, field-based FITness testing in PREschool children. The PREFIT battery is composed of the following tests: the 20 m shuttle-run test for assessing cardiorespiratory fitness, the handgrip-strength and the standing long-jump tests for assessing musculoskeletal fitness, and the 4 × 10 m shuttle run and the one-leg-stance tests for assessing motor fitness, i.e. speed/agility and balance, respectively. The rationale for the selection of each of the tests included in the PREFIT battery is provided in this review, as well as directions for future research. Levels of evidence based on quality assessment of selected studies could not be constructed due to the limited number of studies identified for each test. The present systematic review has identified a need for further research on the validity of fitness tests in preschool children, as well as on their relationship with health. Due to this limited information, the PREFIT battery hereby proposed is based on the output of the current systematic review in preschool children, together with existing evidence in older children and adolescents. While we wait for more evidence to be accumulated in preschool children, the PREFIT battery hereby proposed is a useful tool for assessing physical fitness in children aged 3-5 years.

Empirical scaling laws for coronal heating

NASA Technical Reports Server (NTRS)

Golub, L.

1983-01-01

The origins and uses of scaling laws in studies of stellar outer atmospheres are reviewed with particular emphasis on the properties of coronal loops. Some evidence is presented for a fundamental structuring of the solar corona and the thermodynamics of scaling laws are discussed. It is found that magnetic field-related scaling laws can be obtained by relating coronal pressure, temperature, and magnetic field strength. Available data validate this method. Some parameters of the theory, however, must be treated as adjustable, and it is considered necessary to examine data from other stars in order to determine the validity of the parameters. Using detailed observational data, the applicability of single loop models is examined.

Physical activity measurement instruments for children with cerebral palsy: a systematic review.

PubMed

Capio, Catherine M; Sit, Cindy H P; Abernethy, Bruce; Rotor, Esmerita R

2010-10-01

this paper is a systematic review of physical activity measurement instruments for field-based studies involving children with cerebral palsy (CP). database searches using PubMed Central, MEDLINE, CINAHL Plus, PsycINFO, EMBASE, Cochrane Library, and PEDro located 12 research papers, identifying seven instruments that met the inclusion criteria of (1) having been developed for children aged 0 to 18 years, (2) having been used to evaluate a physical activity dimension, and (3) having been used in a field-based study involving children with CP. The instruments reviewed were the Activities Scale for Kids - Performance version (ASKp), the Canada Fitness Survey, the Children's Assessment of Participation and Enjoyment/Preferences for Activities of Children (CAPE/PAC), the Compendium of Physical Activities, the Physical Activity Questionnaire - Adolescents (PAQ-A), StepWatch, and the Uptimer. Second-round searches yielded 11 more papers, providing reliability and validity evidence for the instruments. the instruments measure physical activity frequency, mode, domain, and duration. Although most instruments demonstrated adequate reliability and validity, only the ASKp and CAPE/PAC have established reliability and validity for children with physical disabilities; the Uptimer has established concurrent validity. No instrument measuring intensity in free-living has been validated or found reliable for children with CP. the findings suggest that further studies are needed to examine the methodological properties of physical activity measurement in children with CP. Combining subjective and objective instruments is recommended to achieve better understanding of physical activity participation.

RELIABILITY AND VALIDITY OF A BIOMECHANICALLY BASED ANALYSIS METHOD FOR THE TENNIS SERVE

PubMed Central

Kibler, W. Ben; Lamborn, Leah; Smith, Belinda J.; English, Tony; Jacobs, Cale; Uhl, Tim L.

2017-01-01

Background An observational tennis serve analysis (OTSA) tool was developed using previously established body positions from three-dimensional kinematic motion analysis studies. These positions, defined as nodes, have been associated with efficient force production and minimal joint loading. However, the tool has yet to be examined scientifically. Purpose The primary purpose of this investigation was to determine the inter-observer reliability for each node between two health care professionals (HCPs) that developed the OTSA, and secondarily to investigate the validity of the OTSA. Methods Two separate studies were performed to meet these objectives. An inter-observer reliability study preceded the validity study by examining 28 videos of players serving. Two HCPs graded each video and scored the presence or absence of obtaining each node. Discriminant validity was determined in 33 tennis players using video taped records of three first serves. Serve mechanics were graded using the OSTA and categorized players into those with good ( ≥ 5) and poor ( ≤ 4) mechanics. Participants performed a series of field tests to evaluate trunk flexibility, lower extremity and trunk power, and dynamic balance. Results The group with good mechanics demonstrated greater backward trunk flexibility (p=0.02), greater rotational power (p=0.02), and higher single leg countermovement jump (p=0.05). Reliability of the OTSA ranged from K = 0.36-1.0, with the majority of all the nodes displaying substantial reliability (K>0.61). Conclusion This study provides HCPs with a valid and reliable field tool used to assess serve mechanics. Physical characteristics of trunk mobility and power appear to discriminate serve mechanics between players. Future intervention studies are needed to determine if improvement in physical function contribute to improved serve mechanics. Level of Evidence 3 PMID:28593098

Development of assessment instruments to measure critical thinking skills

NASA Astrophysics Data System (ADS)

Sumarni, W.; Supardi, K. I.; Widiarti, N.

2018-04-01

Assessment instruments that is commonly used in the school generally have not been orientated on critical thinking skills. The purpose of this research is to develop assessment instruments to measure critical thinking skills, to test validity, reliability, and practicality. This type of research is Research and Development. There are two stages on the preface step, which are field study and literacy study. On the development steps, there some parts, which are 1) instrument construction, 2) expert validity, 3) limited scale tryout and 4) narrow scale try-out. The developed assessment instrument are analysis essay and problem solving. Instruments were declared valid, reliable and practical.

Critical validation studies of neurofeedback.

PubMed

Gruzelier, John; Egner, Tobias

2005-01-01

The field of neurofeedback training has proceeded largely without validation. In this article the authors review studies directed at validating sensory motor rhythm, beta and alpha-theta protocols for improving attention, memory, and music performance in healthy participants. Importantly, benefits were demonstrable with cognitive and neurophysiologic measures that were predicted on the basis of regression models of learning to enhance sensory motor rhythm and beta activity. The first evidence of operant control over the alpha-theta ratio is provided, together with remarkable improvements in artistic aspects of music performance equivalent to two class grades in conservatory students. These are initial steps in providing a much needed scientific basis to neurofeedback.

Bigfoot Field Manual

NASA Astrophysics Data System (ADS)

Campbell, J. L.; Burrows, S.; Gower, S. T.; Cohen, W. B.

1999-09-01

The BigFoot Project is funded by the Earth Science Enterprise to collect and organize data to be used in the EOS Validation Program. The data collected by the BigFoot Project are unique in being ground-based observations coincident with satellite overpasses. In addition to collecting data, the BigFoot project will develop and test new algorithms for scaling point measurements to the same spatial scales as the EOS satellite products. This BigFoot Field Manual Mill be used to achieve completeness and consistency of data collected at four initial BigFoot sites and at future sites that may collect similar validation data. Therefore, validation datasets submitted to the ORNL DAAC that have been compiled in a manner consistent with the field manual will be especially valuable in the validation program.

Characterization of shrubland ecosystem components as continuous fields in the northwest United States

USGS Publications Warehouse

Xian, George Z.; Homer, Collin G.; Rigge, Matthew B.; Shi, Hua; Meyer, Debbie

2015-01-01

Accurate and consistent estimates of shrubland ecosystem components are crucial to a better understanding of ecosystem conditions in arid and semiarid lands. An innovative approach was developed by integrating multiple sources of information to quantify shrubland components as continuous field products within the National Land Cover Database (NLCD). The approach consists of several procedures including field sample collections, high-resolution mapping of shrubland components using WorldView-2 imagery and regression tree models, Landsat 8 radiometric balancing and phenological mosaicking, medium resolution estimates of shrubland components following different climate zones using Landsat 8 phenological mosaics and regression tree models, and product validation. Fractional covers of nine shrubland components were estimated: annual herbaceous, bare ground, big sagebrush, herbaceous, litter, sagebrush, shrub, sagebrush height, and shrub height. Our study area included the footprint of six Landsat 8 scenes in the northwestern United States. Results show that most components have relatively significant correlations with validation data, have small normalized root mean square errors, and correspond well with expected ecological gradients. While some uncertainties remain with height estimates, the model formulated in this study provides a cross-validated, unbiased, and cost effective approach to quantify shrubland components at a regional scale and advances knowledge of horizontal and vertical variability of these components.

Validation of Field Methods to Assess Body Fat Percentage in Elite Youth Soccer Players.

PubMed

Munguia-Izquierdo, Diego; Suarez-Arrones, Luis; Di Salvo, Valter; Paredes-Hernandez, Victor; Alcazar, Julian; Ara, Ignacio; Kreider, Richard; Mendez-Villanueva, Alberto

2018-05-01

This study determined the most effective field method for quantifying body fat percentage in male elite youth soccer players and developed prediction equations based on anthropometric variables. Forty-four male elite-standard youth soccer players aged 16.3-18.0 years underwent body fat percentage assessments, including bioelectrical impedance analysis and the calculation of various skinfold-based prediction equations. Dual X-ray absorptiometry provided a criterion measure of body fat percentage. Correlation coefficients, bias, limits of agreement, and differences were used as validity measures, and regression analyses were used to develop soccer-specific prediction equations. The equations from Sarria et al. (1998) and Durnin & Rahaman (1967) reached very large correlations and the lowest biases, and they reached neither the practically worthwhile difference nor the substantial difference between methods. The new youth soccer-specific skinfold equation included a combination of triceps and supraspinale skinfolds. None of the practical methods compared in this study are adequate for estimating body fat percentage in male elite youth soccer players, except for the equations from Sarria et al. (1998) and Durnin & Rahaman (1967). The new youth soccer-specific equation calculated in this investigation is the only field method specifically developed and validated in elite male players, and it shows potentially good predictive power. © Georg Thieme Verlag KG Stuttgart · New York.

Development of the Assessment of Belief Conflict in Relationship-14 (ABCR-14).

PubMed

Kyougoku, Makoto; Teraoka, Mutsumi; Masuda, Noriko; Ooura, Mariko; Abe, Yasushi

2015-01-01

Nurses and other healthcare workers frequently experience belief conflict, one of the most important, new stress-related problems in both academic and clinical fields. In this study, using a sample of 1,683 nursing practitioners, we developed The Assessment of Belief Conflict in Relationship-14 (ABCR-14), a new scale that assesses belief conflict in the healthcare field. Standard psychometric procedures were used to develop and test the scale, including a qualitative framework concept and item-pool development, item reduction, and scale development. We analyzed the psychometric properties of ABCR-14 according to entropy, polyserial correlation coefficient, exploratory factor analysis, confirmatory factor analysis, average variance extracted, Cronbach's alpha, Pearson product-moment correlation coefficient, and multidimensional item response theory (MIRT). The results of the analysis supported a three-factor model consisting of 14 items. The validity and reliability of ABCR-14 was suggested by evidence from high construct validity, structural validity, hypothesis testing, internal consistency reliability, and concurrent validity. The result of the MIRT offered strong support for good item response of item slope parameters and difficulty parameters. However, the ABCR-14 Likert scale might need to be explored from the MIRT point of view. Yet, as mentioned above, there is sufficient evidence to support that ABCR-14 has high validity and reliability. The ABCR-14 demonstrates good psychometric properties for nursing belief conflict. Further studies are recommended to confirm its application in clinical practice.

Introducing the VISAGE project - Visualization for Integrated Satellite, Airborne, and Ground-based data Exploration

NASA Astrophysics Data System (ADS)

Gatlin, P. N.; Conover, H.; Berendes, T.; Maskey, M.; Naeger, A. R.; Wingo, S. M.

2017-12-01

A key component of NASA's Earth observation system is its field experiments, for intensive observation of particular weather phenomena, or for ground validation of satellite observations. These experiments collect data from a wide variety of airborne and ground-based instruments, on different spatial and temporal scales, often in unique formats. The field data are often used with high volume satellite observations that have very different spatial and temporal coverage. The challenges inherent in working with such diverse datasets make it difficult for scientists to rapidly collect and analyze the data for physical process studies and validation of satellite algorithms. The newly-funded VISAGE project will address these issues by combining and extending nascent efforts to provide on-line data fusion, exploration, analysis and delivery capabilities. A key building block is the Field Campaign Explorer (FCX), which allows users to examine data collected during field campaigns and simplifies data acquisition for event-based research. VISAGE will extend FCX's capabilities beyond interactive visualization and exploration of coincident datasets, to provide interrogation of data values and basic analyses such as ratios and differences between data fields. The project will also incorporate new, higher level fused and aggregated analysis products from the System for Integrating Multi-platform data to Build the Atmospheric column (SIMBA), which combines satellite and ground-based observations into a common gridded atmospheric column data product; and the Validation Network (VN), which compiles a nationwide database of coincident ground- and satellite-based radar measurements of precipitation for larger scale scientific analysis. The VISAGE proof-of-concept will target "golden cases" from Global Precipitation Measurement Ground Validation campaigns. This presentation will introduce the VISAGE project, initial accomplishments and near term plans.

Generating Vegetation Leaf Area Index Earth System Data Record from Multiple Sensors. Part 2; Implementation, Analysis and Validation

NASA Technical Reports Server (NTRS)

Ganguly, Sangram; Samanta, Arindam; Schull, Mitchell A.; Shabanov, Nikolay V.; Milesi, Cristina; Nemani, Ramajrushna R,; Knyazikhin, Yuri; Myneni, Ranga B.

2008-01-01

The evaluation of a new global monthly leaf area index (LAI) data set for the period July 1981 to December 2006 derived from AVHRR Normalized Difference Vegetation Index (NDVI) data is described. The physically based algorithm is detailed in the first of the two part series. Here, the implementation, production and evaluation of the data set are described. The data set is evaluated both by direct comparisons to ground data and indirectly through inter-comparisons with similar data sets. This indirect validation showed satisfactory agreement with existing LAI products, importantly MODIS, at a range of spatial scales, and significant correlations with key climate variables in areas where temperature and precipitation limit plant growth. The data set successfully reproduced well-documented spatio-temporal trends and inter-annual variations in vegetation activity in the northern latitudes and semi-arid tropics. Comparison with plot scale field measurements over homogeneous vegetation patches indicated a 7% underestimation when all major vegetation types are taken into account. The error in mean values obtained from distributions of AVHRR LAI and high-resolution field LAI maps for different biomes is within 0.5 LAI for six out of the ten selected sites. These validation exercises though limited by the amount of field data, and thus less than comprehensive, indicated satisfactory agreement between the LAI product and field measurements. Overall, the intercomparison with short-term LAI data sets, evaluation of long term trends with known variations in climate variables, and validation with field measurements together build confidence in the utility of this new 26 year LAI record for long term vegetation monitoring and modeling studies.

Predicting implementation from organizational readiness for change: a study protocol

PubMed Central

2011-01-01

Background There is widespread interest in measuring organizational readiness to implement evidence-based practices in clinical care. However, there are a number of challenges to validating organizational measures, including inferential bias arising from the halo effect and method bias - two threats to validity that, while well-documented by organizational scholars, are often ignored in health services research. We describe a protocol to comprehensively assess the psychometric properties of a previously developed survey, the Organizational Readiness to Change Assessment. Objectives Our objective is to conduct a comprehensive assessment of the psychometric properties of the Organizational Readiness to Change Assessment incorporating methods specifically to address threats from halo effect and method bias. Methods and Design We will conduct three sets of analyses using longitudinal, secondary data from four partner projects, each testing interventions to improve the implementation of an evidence-based clinical practice. Partner projects field the Organizational Readiness to Change Assessment at baseline (n = 208 respondents; 53 facilities), and prospectively assesses the degree to which the evidence-based practice is implemented. We will conduct predictive and concurrent validities using hierarchical linear modeling and multivariate regression, respectively. For predictive validity, the outcome is the change from baseline to follow-up in the use of the evidence-based practice. We will use intra-class correlations derived from hierarchical linear models to assess inter-rater reliability. Two partner projects will also field measures of job satisfaction for convergent and discriminant validity analyses, and will field Organizational Readiness to Change Assessment measures at follow-up for concurrent validity (n = 158 respondents; 33 facilities). Convergent and discriminant validities will test associations between organizational readiness and different aspects of job satisfaction: satisfaction with leadership, which should be highly correlated with readiness, versus satisfaction with salary, which should be less correlated with readiness. Content validity will be assessed using an expert panel and modified Delphi technique. Discussion We propose a comprehensive protocol for validating a survey instrument for assessing organizational readiness to change that specifically addresses key threats of bias related to halo effect, method bias and questions of construct validity that often go unexplored in research using measures of organizational constructs. PMID:21777479

How feasible is remote 3D dosimetry for MR guided Radiation Therapy (MRgRT)?

NASA Astrophysics Data System (ADS)

Mein, S.; Rankine, L.; Miles, D.; Juang, T.; Cai, B.; Curcuru, A.; Mutic, S.; Fenoli, J.; Adamovics, J.; Li, H.; Oldham, M.

2017-05-01

To develop and apply a remote dosimetry protocol with PRESAGE® radiochromic plastic and optical-CT readout in the validation of MRI guided radiation therapy (MRgRT) treatments (MRIdian® by ViewRay®). Through multi-institutional collaboration we performed PRESAGE® dosimetry studies in 4ml cuvettes to investigate dose-response linearity, MR-compatibility, and energy-independence. An open calibration field and symmetrical 3-field plans were delivered to 10cm diameter PRESAGE® to examine percent depth dose and response uniformity under a magnetic field. Evidence of non-linear dose response led to a large volume PRESAGE® study where small corrections were developed for temporally- and spatially-dependent behaviors observed between irradiation and delayed readout. TG-119 plans were created in the MRIdian® TPS and then delivered to 14.5cm 2kg PRESAGE® dosimeters. Through the domestic investigation of an off-site MRgRT system, a refined 3D remote dosimetry protocol is presented capable of validation of advanced MRgRT radiation treatments.

Ocean Optics Protocols for Satellite Ocean Color Sensor Validation. Volume 4; Inherent Optical Properties: Instruments, Characterizations, Field Measurements and Data Analysis Protocols; Revised

NASA Technical Reports Server (NTRS)

Mueller, J. L. (Editor); Fargion, Giuletta S. (Editor); McClain, Charles R. (Editor); Pegau, Scott; Zaneveld, J. Ronald V.; Mitchell, B. Gregg; Kahru, Mati; Wieland, John; Stramska, Malgorzat

2003-01-01

This document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. The document is organized into 6 separate volumes as Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4. Volume I: Introduction, Background and Conventions; Volume II: Instrument Specifications, Characterization and Calibration; Volume III: Radiometric Measurements and Data Analysis Methods; Volume IV: Inherent Optical Properties: Instruments, Characterization, Field Measurements and Data Analysis Protocols; Volume V: Biogeochemical and Bio-Optical Measurements and Data Analysis Methods; Volume VI: Special Topics in Ocean Optics Protocols and Appendices. The earlier version of Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 3 (Mueller and Fargion 2002, Volumes 1 and 2) is entirely superseded by the six volumes of Revision 4 listed above.

Development and Validation of Search Filters to Identify Articles on Family Medicine in Online Medical Databases

PubMed Central

Pols, David H.J.; Bramer, Wichor M.; Bindels, Patrick J.E.; van de Laar, Floris A.; Bohnen, Arthur M.

2015-01-01

Physicians and researchers in the field of family medicine often need to find relevant articles in online medical databases for a variety of reasons. Because a search filter may help improve the efficiency and quality of such searches, we aimed to develop and validate search filters to identify research studies of relevance to family medicine. Using a new and objective method for search filter development, we developed and validated 2 search filters for family medicine. The sensitive filter had a sensitivity of 96.8% and a specificity of 74.9%. The specific filter had a specificity of 97.4% and a sensitivity of 90.3%. Our new filters should aid literature searches in the family medicine field. The sensitive filter may help researchers conducting systematic reviews, whereas the specific filter may help family physicians find answers to clinical questions at the point of care when time is limited. PMID:26195683

Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4, Volume IV: Inherent Optical Properties: Instruments, Characterizations, Field Measurements and Data Analysis Protocols

NASA Technical Reports Server (NTRS)

Mueller, J. L.; Fargion, G. S.; McClain, C. R. (Editor); Pegau, S.; Zanefeld, J. R. V.; Mitchell, B. G.; Kahru, M.; Wieland, J.; Stramska, M.

2003-01-01

This document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparision and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. The document is organized into 6 separate volumes as Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4. Volume I: Introduction, Background, and Conventions; Volume II: Instrument Specifications, Characterization and Calibration; Volume III: Radiometric Measurements and Data Analysis Methods; Volume IV: Inherent Optical Properties: Instruments, Characterization, Field Measurements and Data Analysis Protocols; Volume V: Biogeochemical and Bio-Optical Measurements and Data Analysis Methods; Volume VI: Special Topics in Ocean Optics Protocols and Appendices. The earlier version of Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 3 is entirely superseded by the six volumes of Revision 4 listed above.

Validity of Selected Lab and Field Tests of Physical Working Capacity.

ERIC Educational Resources Information Center

Burke, Edmund J.

The validity of selected lab and field tests of physical working capacity was investigated. Forty-four male college students were administered a series of lab and field tests of physical working capacity. Lab tests include a test of maximum oxygen uptake, the PWC 170 test, the Harvard Step Test, the Progressive Pulse Ratio Test, Margaria Test of…

Toward the Development and Validation of a Career Coach Competency Model

ERIC Educational Resources Information Center

Hatala, John-Paul; Hisey, Lee

2011-01-01

The career coaching profession is a dynamic field that has grown over the last decade. However, there exists a limitation to this field's development, as there is no universally accepted definition or empirically based competencies. There were three phases to the study. In the first phase, a conceptual model was developed that highlights four…

The Definition and Measurement of Small Military Unit Team Functions. Final Report, July 1980-October 1981.

ERIC Educational Resources Information Center

Shiflett, Samuel; And Others

A study was undertaken to improve the measurement of small team performance within the Army. A provisional taxonomy of team-level performance functions was field-validated; criteria and measures of the functions were developed; and their reliability was examined. The provisional taxonomy, used for observing Army field training exercises, was used…

A validation study of a rapid field-based rating system for discriminating among flow permanence classes of headwater streams in South Carolina

EPA Science Inventory

Rapid field-based protocols for classifying flow permanence of headwater streams are needed to inform timely regulatory decisions. Such an existing method was developed for and has been used in North Carolina since 1997. The method uses ordinal scoring of 26 geomorphology, hydr...

Prototype of NASA's Global Precipitation Measurement Mission Ground Validation System

NASA Technical Reports Server (NTRS)

Schwaller, M. R.; Morris, K. R.; Petersen, W. A.

2007-01-01

NASA is developing a Ground Validation System (GVS) as one of its contributions to the Global Precipitation Mission (GPM). The GPM GVS provides an independent means for evaluation, diagnosis, and ultimately improvement of GPM spaceborne measurements and precipitation products. NASA's GPM GVS consists of three elements: field campaigns/physical validation, direct network validation, and modeling and simulation. The GVS prototype of direct network validation compares Tropical Rainfall Measuring Mission (TRMM) satellite-borne radar data to similar measurements from the U.S. national network of operational weather radars. A prototype field campaign has also been conducted; modeling and simulation prototypes are under consideration.

Assessing the significance of pedobarographic signals using random field theory.

PubMed

Pataky, Todd C

2008-08-07

Traditional pedobarographic statistical analyses are conducted over discrete regions. Recent studies have demonstrated that regionalization can corrupt pedobarographic field data through conflation when arbitrary dividing lines inappropriately delineate smooth field processes. An alternative is to register images such that homologous structures optimally overlap and then conduct statistical tests at each pixel to generate statistical parametric maps (SPMs). The significance of SPM processes may be assessed within the framework of random field theory (RFT). RFT is ideally suited to pedobarographic image analysis because its fundamental data unit is a lattice sampling of a smooth and continuous spatial field. To correct for the vast number of multiple comparisons inherent in such data, recent pedobarographic studies have employed a Bonferroni correction to retain a constant family-wise error rate. This approach unfortunately neglects the spatial correlation of neighbouring pixels, so provides an overly conservative (albeit valid) statistical threshold. RFT generally relaxes the threshold depending on field smoothness and on the geometry of the search area, but it also provides a framework for assigning p values to suprathreshold clusters based on their spatial extent. The current paper provides an overview of basic RFT concepts and uses simulated and experimental data to validate both RFT-relevant field smoothness estimations and RFT predictions regarding the topological characteristics of random pedobarographic fields. Finally, previously published experimental data are re-analysed using RFT inference procedures to demonstrate how RFT yields easily understandable statistical results that may be incorporated into routine clinical and laboratory analyses.

A unified approach to validation, reliability, and education study design for surgical technical skills training.

PubMed

Sweet, Robert M; Hananel, David; Lawrenz, Frances

2010-02-01

To present modern educational psychology theory and apply these concepts to validity and reliability of surgical skills training and assessment. In a series of cross-disciplinary meetings, we applied a unified approach of behavioral science principles and theory to medical technical skills education given the recent advances in the theories in the field of behavioral psychology and statistics. While validation of the individual simulation tools is important, it is only one piece of a multimodal curriculum that in and of itself deserves examination and study. We propose concurrent validation throughout the design of simulation-based curriculum rather than once it is complete. We embrace the concept that validity and curriculum development are interdependent, ongoing processes that are never truly complete. Individual predictive, construct, content, and face validity aspects should not be considered separately but as interdependent and complementary toward an end application. Such an approach could help guide our acceptance and appropriate application of these exciting new training and assessment tools for technical skills training in medicine.

Theoretical validation for changing magnetic fields of systems of permanent magnets of drum separators

NASA Astrophysics Data System (ADS)

Lozovaya, S. Y.; Lozovoy, N. M.; Okunev, A. N.

2018-03-01

This article is devoted to the theoretical validation of the change in magnetic fields created by the permanent magnet systems of the drum separators. In the article, using the example of a magnetic separator for enrichment of highly magnetic ores, the method of analytical calculation of the magnetic fields of systems of permanent magnets based on the Biot-Savart-Laplace law, the equivalent solenoid method, and the superposition principle of fields is considered.

Reproducibility of studies on text mining for citation screening in systematic reviews: Evaluation and checklist.

PubMed

Olorisade, Babatunde Kazeem; Brereton, Pearl; Andras, Peter

2017-09-01

Independent validation of published scientific results through study replication is a pre-condition for accepting the validity of such results. In computation research, full replication is often unrealistic for independent results validation, therefore, study reproduction has been justified as the minimum acceptable standard to evaluate the validity of scientific claims. The application of text mining techniques to citation screening in the context of systematic literature reviews is a relatively young and growing computational field with high relevance for software engineering, medical research and other fields. However, there is little work so far on reproduction studies in the field. In this paper, we investigate the reproducibility of studies in this area based on information contained in published articles and we propose reporting guidelines that could improve reproducibility. The study was approached in two ways. Initially we attempted to reproduce results from six studies, which were based on the same raw dataset. Then, based on this experience, we identified steps considered essential to successful reproduction of text mining experiments and characterized them to measure how reproducible is a study given the information provided on these steps. 33 articles were systematically assessed for reproducibility using this approach. Our work revealed that it is currently difficult if not impossible to independently reproduce the results published in any of the studies investigated. The lack of information about the datasets used limits reproducibility of about 80% of the studies assessed. Also, information about the machine learning algorithms is inadequate in about 27% of the papers. On the plus side, the third party software tools used are mostly free and available. The reproducibility potential of most of the studies can be significantly improved if more attention is paid to information provided on the datasets used, how they were partitioned and utilized, and how any randomization was controlled. We introduce a checklist of information that needs to be provided in order to ensure that a published study can be reproduced. Copyright © 2017 Elsevier Inc. All rights reserved.

Chemometric and biological validation of a capillary electrophoresis metabolomic experiment of Schistosoma mansoni infection in mice.

PubMed

Garcia-Perez, Isabel; Angulo, Santiago; Utzinger, Jürg; Holmes, Elaine; Legido-Quigley, Cristina; Barbas, Coral

2010-07-01

Metabonomic and metabolomic studies are increasingly utilized for biomarker identification in different fields, including biology of infection. The confluence of improved analytical platforms and the availability of powerful multivariate analysis software have rendered the multiparameter profiles generated by these omics platforms a user-friendly alternative to the established analysis methods where the quality and practice of a procedure is well defined. However, unlike traditional assays, validation methods for these new multivariate profiling tools have yet to be established. We propose a validation for models obtained by CE fingerprinting of urine from mice infected with the blood fluke Schistosoma mansoni. We have analysed urine samples from two sets of mice infected in an inter-laboratory experiment where different infection methods and animal husbandry procedures were employed in order to establish the core biological response to a S. mansoni infection. CE data were analysed using principal component analysis. Validation of the scores consisted of permutation scrambling (100 repetitions) and a manual validation method, using a third of the samples (not included in the model) as a test or prediction set. The validation yielded 100% specificity and 100% sensitivity, demonstrating the robustness of these models with respect to deciphering metabolic perturbations in the mouse due to a S. mansoni infection. A total of 20 metabolites across the two experiments were identified that significantly discriminated between S. mansoni-infected and noninfected control samples. Only one of these metabolites, allantoin, was identified as manifesting different behaviour in the two experiments. This study shows the reproducibility of CE-based metabolic profiling methods for disease characterization and screening and highlights the importance of much needed validation strategies in the emerging field of metabolomics.

Field validation of a drive-by bridge inspection system with wireless BWIM + NDE devices : final report.

DOT National Transportation Integrated Search

2016-09-01

In this project, researchers developed and performed field validation of a wireless structural sensing system for a variety of bridge response measurements, including strain, acceleration, and displacement. The research team used the wireless strain ...

Developing workshop module of realistic mathematics education: Follow-up workshop

NASA Astrophysics Data System (ADS)

Palupi, E. L. W.; Khabibah, S.

2018-01-01

Realistic Mathematics Education (RME) is a learning approach which fits the aim of the curriculum. The success of RME in teaching mathematics concepts, triggering students’ interest in mathematics and teaching high order thinking skills to the students will make teachers start to learn RME. Hence, RME workshop is often offered and done. This study applied development model proposed by Plomp. Based on the study by RME team, there are three kinds of RME workshop: start-up workshop, follow-up workshop, and quality boost. However, there is no standardized or validated module which is used in that workshops. This study aims to develop a module of RME follow-up workshop which is valid and can be used. Plopm’s developmental model includes materials analysis, design, realization, implementation, and evaluation. Based on the validation, the developed module is valid. While field test shows that the module can be used effectively.

Aircraft Wake Vortex Spacing System (AVOSS) Performance Update and Validation Study

NASA Technical Reports Server (NTRS)

Rutishauser, David K.; OConnor, Cornelius J.

2001-01-01

An analysis has been performed on data generated from the two most recent field deployments of the Aircraft Wake VOrtex Spacing System (AVOSS). The AVOSS provides reduced aircraft spacing criteria for wake vortex avoidance as compared to the FAA spacing applied under Instrument Flight Rules (IFR). Several field deployments culminating in a system demonstration at Dallas Fort Worth (DFW) International Airport in the summer of 2000 were successful in showing a sound operational concept and the system's potential to provide a significant benefit to airport operations. For DFW, a predicted average throughput increase of 6% was observed. This increase implies 6 or 7 more aircraft on the ground in a one-hour period for DFW operations. Several studies of performance correlations to system configuration options, design options, and system inputs are also reported. The studies focus on the validation performance of the system.

Ethical issues in field research: balancing competing values.

PubMed

O'Neill, P

1990-04-01

An ethical issue becomes a dilemma when the psychologist is pulled in different directions by competing values. This paper will focus on the conflict between experimental and ethical values inherent in field research. The problem has special significance in community psychology, which gives priority to studying, in natural settings, those affected by social problems. An example is given of research that required observation of family interaction in the homes of convicted child abusers. The case demonstrates that the value of ecological validity often conflicts with the need to protect privacy and obtain uncoerced consent. Other ethical constraints, including the duty to report lawbreaking and to protect the public from harm, may threaten research validity.

SIMBIOS Normalized Water-Leaving Radiance Calibration and Validation: Sensor Response, Atmospheric Corrections, Stray Light and Sun Glint. Chapter 14

NASA Technical Reports Server (NTRS)

Mueller, James L.

2001-01-01

This Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) contract supports acquisition of match up radiometric and bio-optical data for validation of Sea-Viewing Wide Field-of-view Sensor (SeaWiFS) and other ocean color satellites, and evaluation of uncertainty budgets and protocols for in situ measurements of normalized water leaving radiances.

How Attitudes towards Statistics Courses and the Field of Statistics Predicts Statistics Anxiety among Undergraduate Social Science Majors: A Validation of the Statistical Anxiety Scale

ERIC Educational Resources Information Center

O'Bryant, Monique J.

2017-01-01

The aim of this study was to validate an instrument that can be used by instructors or social scientist who are interested in evaluating statistics anxiety. The psychometric properties of the English version of the Statistical Anxiety Scale (SAS) was examined through a confirmatory factor analysis of scores from a sample of 323 undergraduate…

The methodological quality of diagnostic test accuracy studies for musculoskeletal conditions can be improved.

PubMed

Henschke, Nicholas; Keuerleber, Julia; Ferreira, Manuela; Maher, Christopher G; Verhagen, Arianne P

2014-04-01

To provide an overview of reporting and methodological quality in diagnostic test accuracy (DTA) studies in the musculoskeletal field and evaluate the use of the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. A literature review identified all systematic reviews that evaluated the accuracy of clinical tests to diagnose musculoskeletal conditions and used the QUADAS checklist. Two authors screened all identified reviews and extracted data on the target condition, index tests, reference standard, included studies, and QUADAS items. A descriptive analysis of the QUADAS checklist was performed, along with Rasch analysis to examine the construct validity and internal reliability. A total of 19 systematic reviews were included, which provided data on individual items of the QUADAS checklist for 392 DTA studies. In the musculoskeletal field, uninterpretable or intermediate test results are commonly not reported, with 175 (45%) studies scoring "no" to this item. The proportion of studies fulfilling certain items varied from 22% (item 11) to 91% (item 3). The interrater reliability of the QUADAS checklist was good and Rasch analysis showed excellent construct validity and internal consistency. This overview identified areas where the reporting and performance of diagnostic studies within the musculoskeletal field can be improved. Copyright © 2014 Elsevier Inc. All rights reserved.

MODELS FOR SUBMARINE OUTFALL - VALIDATION AND PREDICTION UNCERTAINTIES

EPA Science Inventory

This address reports on some efforts to verify and validate dilution models, including those found in Visual Plumes. This is done in the context of problem experience: a range of problems, including different pollutants such as bacteria; scales, including near-field and far-field...

Validation of a low field Rheo-NMR instrument and application to shear-induced migration of suspended non-colloidal particles in Couette flow

NASA Astrophysics Data System (ADS)

Colbourne, A. A.; Blythe, T. W.; Barua, R.; Lovett, S.; Mitchell, J.; Sederman, A. J.; Gladden, L. F.

2018-01-01

Nuclear magnetic resonance rheology (Rheo-NMR) is a valuable tool for studying the transport of suspended non-colloidal particles, important in many commercial processes. The Rheo-NMR imaging technique directly and quantitatively measures fluid displacement as a function of radial position. However, the high field magnets typically used in these experiments are unsuitable for the industrial environment and significantly hinder the measurement of shear stress. We introduce a low field Rheo-NMR instrument (1 H resonance frequency of 10.7MHz), which is portable and suitable as a process monitoring tool. This system is applied to the measurement of steady-state velocity profiles of a Newtonian carrier fluid suspending neutrally-buoyant non-colloidal particles at a range of concentrations. The large particle size (diameter > 200 μm) in the system studied requires a wide-gap Couette geometry and the local rheology was expected to be controlled by shear-induced particle migration. The low-field results are validated against high field Rheo-NMR measurements of consistent samples at matched shear rates. Additionally, it is demonstrated that existing models for particle migration fail to adequately describe the solid volume fractions measured in these systems, highlighting the need for improvement. The low field implementation of Rheo-NMR is complementary to shear stress rheology, such that the two techniques could be combined in a single instrument.

from the Adolescents’ Perspective in Malaysia

PubMed

Mohd Zin, Faridah; Hillaluddin, Azlin Hilma; Mustaffa, Jamaludin

2017-05-01

Objective: This study aims to develop, validate and determine the reliability of an interactive multimedia strategy to prevent tobacco use among the young (TUPY-S) from an adolescents’ perspective. Methods: A descriptive study design was utilized. A modular instruction guideline by Russel (1974) was followed in the entire process, comprising a feasibility study, a review of existing modules, specification of the objectives, identification of the construct criterion items, learner analysis and entry behavior specification, establishment of the sequence instruction and media selection, a tryout with students and a field test. Result: Feasibility was agreed among the researchers and the school authorities. Culturally suitable rigorously developed tobacco use preventive strategies delivered using information technology (IT) are lacking in the literature. The objective of TUPY-S is to prevent tobacco use among adolescents living in Malaysia. Identified construct criterion items include knowledge, attitude, intention to use, self-efficacy, and refusal skill. The target population was early adolescents belonging to generation-Z. Content was developed from the adolescents’ perspective and delivered using IT in Malay language. Content validity, assessed by six experts in the field and module development, was good at 86%. The students’ tryout showed satisfactory face validity subjectively and objectively (85.5%) and high alpha Cronbach reliability (0.91). Conclusion: TUPY-S was confirmed to suit early adolescents of the current generation living in Malaysia. It demonstrated good content validity among the experts, satisfactory face validity and reliability among the target population. TUPY-S is ready to be evaluated for its effectiveness among early adolescents. Creative Commons Attribution License

Extended effective field theory of inflation

NASA Astrophysics Data System (ADS)

Ashoorioon, Amjad; Casadio, Roberto; Cicoli, Michele; Geshnizjani, Ghazal; Kim, Hyung J.

2018-02-01

We present a general framework where the effective field theory of single field inflation is extended by the inclusion of operators with mass dimension 3 and 4 in the unitary gauge. These higher dimensional operators introduce quartic and sextic corrections to the dispersion relation. We study the regime of validity of this extended effective field theory of inflation and the effect of these higher dimensional operators on CMB observables associated with scalar perturbations, such as the speed of sound, the amplitude of the power spectrum and the tensor-to-scalar ratio. Tensor perturbations remain instead, unaltered.

Select Methodology for Validating Advanced Satellite Measurement Systems

NASA Technical Reports Server (NTRS)

Larar, Allen M.; Zhou, Daniel K.; Liu, Xi; Smith, William L.

2008-01-01

Advanced satellite sensors are tasked with improving global measurements of the Earth's atmosphere, clouds, and surface to enable enhancements in weather prediction, climate monitoring capability, and environmental change detection. Measurement system validation is crucial to achieving this goal and maximizing research and operational utility of resultant data. Field campaigns including satellite under-flights with well calibrated FTS sensors aboard high-altitude aircraft are an essential part of the validation task. This presentation focuses on an overview of validation methodology developed for assessment of high spectral resolution infrared systems, and includes results of preliminary studies performed to investigate the performance of the Infrared Atmospheric Sounding Interferometer (IASI) instrument aboard the MetOp-A satellite.

Development of an Instrument to Measure Preservice Teachers' Technology Skills, Technology Beliefs, and Technology Barriers

ERIC Educational Resources Information Center

Brush, Thomas; Glazewski, Krista D.; Hew, Khe Foon

2008-01-01

The purpose of this study was to develop and field-test the Technology Skills, Beliefs, and Barriers scale and to determine its validity and reliability for use with preservice teachers. Data were collected from 176 preservice teachers enrolled in a field-based teacher education program located at a major Southwestern university in the United…

Determinants of Success on the ETS Business Major Field Exam for Students in an Undergraduate Multisite Regional University Business Program

ERIC Educational Resources Information Center

Bagamery, Bruce D.; Lasik, John J.; Nixon, Don R.

2005-01-01

Extending previous studies, the authors examined a larger set of variables to identify predictors of student performance on the Educational Testing Service Major Field Exam in Business, which has been shown to be an externally valid measure of student learning outcomes. Significant predictors include gender, whether students took the SAT, and…

Examining Organizational Learning in Schools: The Role of Psychological Safety, Experimentation, and Leadership that Reinforces Learning

ERIC Educational Resources Information Center

Higgins, Monica; Ishimaru, Ann; Holcombe, Rebecca; Fowler, Amy

2012-01-01

This study draws upon theory and methods from the field of organizational behavior to examine organizational learning (OL) in the context of a large urban US school district. We build upon prior literature on OL from the field of organizational behavior to introduce and validate three subscales that assess key dimensions of organizational learning…

COMPUTERIZED EXPERT SYSTEM FOR EVALUATION OF AUTOMATED VISUAL FIELDS FROM THE ISCHEMIC OPTIC NEUROPATHY DECOMPRESSION TRIAL: METHODS, BASELINE FIELDS, AND SIX-MONTH LONGITUDINAL FOLLOW-UP

PubMed Central

Feldon, Steven E

2004-01-01

ABSTRACT Purpose To validate a computerized expert system evaluating visual fields in a prospective clinical trial, the Ischemic Optic Neuropathy Decompression Trial (IONDT). To identify the pattern and within-pattern severity of field defects for study eyes at baseline and 6-month follow-up. Design Humphrey visual field (HVF) change was used as the outcome measure for a prospective, randomized, multi-center trial to test the null hypothesis that optic nerve sheath decompression was ineffective in treating nonarteritic anterior ischemic optic neuropathy and to ascertain the natural history of the disease. Methods An expert panel established criteria for the type and severity of visual field defects. Using these criteria, a rule-based computerized expert system interpreted HVF from baseline and 6-month visits for patients randomized to surgery or careful follow-up and for patients who were not randomized. Results A computerized expert system was devised and validated. The system was then used to analyze HVFs. The pattern of defects found at baseline for patients randomized to surgery did not differ from that of patients randomized to careful follow-up. The most common pattern of defect was a superior and inferior arcuate with central scotoma for randomized eyes (19.2%) and a superior and inferior arcuate for nonrandomized eyes (30.6%). Field patterns at 6 months and baseline were not different. For randomized study eyes, the superior altitudinal defects improved (P = .03), as did the inferior altitudinal defects (P = .01). For nonrandomized study eyes, only the inferior altitudinal defects improved (P = .02). No treatment effect was noted. Conclusions A novel rule-based expert system successfully interpreted visual field defects at baseline of eyes enrolled in the IONDT. PMID:15747764

Academic and Nonacademic Validating Agents on Latinas Mathematics and Science Self Concept A Quantitative Study Utilizing the High School Longitudinal Study of 2009

NASA Astrophysics Data System (ADS)

Garza, Jennifer M.

The purpose of this study is to inform and further the discussion of academic (i.e. teachers and school counselors) and non-academic (i.e. parents, family, friends, etc.) validating agents on Latina students' mathematics and science self-concepts. This study found a relationship between Latina students' interactions with academic and non-academic validating agents and their math and science self-concept at the K-12 level. Through the review of the literature the researcher addresses identifiable factors and strategies that inform the field of education in the areas of validation theory, family characteristics, and access to STEM fields for Latina students. The researcher used an established instrument designed, administered, and validated through the National Center for Education Statistics (NCES). For purposes of this study, a categorical subset of participants who self-identified as being a Latina student was used. As a result, the total subset number in this study was N=1,882. To determine if academic and non-academic validating agents had an observable statistically significant relationship with Latina students' math and science self-concept, a series of one-way ANOVAs were calculated to compare differences in students' math and science self-concept based on academic and non-academic validating agents for the weighted sample of Latinas for the HLS:09 survey. A path analysis was also employed to assess the factors involved in Latina students' math and science self-concepts. The findings are consistent with previous research involving the influence that academic and non-academic validating agents have on the math and science self-concept of Latina students. The results indicated that students who had teachers that believed in the students, regardless of family background, social economic status or home environment influences had higher math and science self concepts than those who did not. Similarly, it was found that students who had counselors that set high standards of learning and believed that all students could do well had higher math and science self concept than those who did not. Students who had parents that encouraged and discussed taking more math and science courses had higher math and science self concepts than those who did not.

FIELD VALIDATION OF A SHEEPSHEAD MINNOW ESTROGEN-RESPONSIVE CDNA MACROARRAY

EPA Science Inventory

Hemmer, Michael J., Iris Knoebl, Becky L. Hemmer, Patrick Larkin, Peggy S. Harris and Nancy D. Denslow. In press. Field Validation of a Sheepshead Minnow Estrogen-Responsive cDNA Macroarray (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portl...

On the validity of cosmic no-hair conjecture in an anisotropic inationary model

NASA Astrophysics Data System (ADS)

Do, Tuan Q.

2018-05-01

We will present main results of our recent investigations on the validity of cosmic no-hair conjecture proposed by Hawking and his colleagues long time ago in the framework of an anisotropic inflationary model proposed by Kanno, Soda, and Watanabe. As a result, we will show that the cosmic no-hair conjecture seems to be generally violated in the Kanno-Soda- Watanabe model for both canonical and non-canonical scalar fields due to the existence of a non-trivial coupling term between scalar and electromagnetic fields. However, we will also show that the validity of the cosmic no-hair conjecture will be ensured once a unusual scalar field called the phantom field, whose kinetic energy term is negative definite, is introduced into the Kanno-Soda-Watanabe model.

Modeling aspects of human memory for scientific study.

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

Caudell, Thomas P.; Watson, Patrick; McDaniel, Mark A.

Working with leading experts in the field of cognitive neuroscience and computational intelligence, SNL has developed a computational architecture that represents neurocognitive mechanisms associated with how humans remember experiences in their past. The architecture represents how knowledge is organized and updated through information from individual experiences (episodes) via the cortical-hippocampal declarative memory system. We compared the simulated behavioral characteristics with those of humans measured under well established experimental standards, controlling for unmodeled aspects of human processing, such as perception. We used this knowledge to create robust simulations of & human memory behaviors that should help move the scientific community closermore » to understanding how humans remember information. These behaviors were experimentally validated against actual human subjects, which was published. An important outcome of the validation process will be the joining of specific experimental testing procedures from the field of neuroscience with computational representations from the field of cognitive modeling and simulation.« less

Development of the Assessment of Belief Conflict in Relationship-14 (ABCR-14)

PubMed Central

Kyougoku, Makoto; Teraoka, Mutsumi; Masuda, Noriko; Ooura, Mariko; Abe, Yasushi

2015-01-01

Purpose Nurses and other healthcare workers frequently experience belief conflict, one of the most important, new stress-related problems in both academic and clinical fields. Methods In this study, using a sample of 1,683 nursing practitioners, we developed The Assessment of Belief Conflict in Relationship-14 (ABCR-14), a new scale that assesses belief conflict in the healthcare field. Standard psychometric procedures were used to develop and test the scale, including a qualitative framework concept and item-pool development, item reduction, and scale development. We analyzed the psychometric properties of ABCR-14 according to entropy, polyserial correlation coefficient, exploratory factor analysis, confirmatory factor analysis, average variance extracted, Cronbach’s alpha, Pearson product-moment correlation coefficient, and multidimensional item response theory (MIRT). Results The results of the analysis supported a three-factor model consisting of 14 items. The validity and reliability of ABCR-14 was suggested by evidence from high construct validity, structural validity, hypothesis testing, internal consistency reliability, and concurrent validity. The result of the MIRT offered strong support for good item response of item slope parameters and difficulty parameters. However, the ABCR-14 Likert scale might need to be explored from the MIRT point of view. Yet, as mentioned above, there is sufficient evidence to support that ABCR-14 has high validity and reliability. Conclusion The ABCR-14 demonstrates good psychometric properties for nursing belief conflict. Further studies are recommended to confirm its application in clinical practice. PMID:26247356

Validation of an incremental field test for the direct assessment of peak oxygen uptake in wheelchair-dependent athletes.

PubMed

Vinet, A; Bernard, P L; Poulain, M; Varray, A; Le Gallais, D; Micallef, J P

1996-05-01

The aim of this study was to validate an incremental field test performed by wheelchair-dependent (WD) athletes. Nine male paraplegic subjects (mean age 28.9 +/- 4.2 years) performed an incremental field test (FT) and a comparable laboratory test (LT) with their own usual wheelchairs. Both tests started with an initial speed of 4 km.hr(-1) and increased by increments of 1 km.hr(-1) every minute until volitional exhaustion. The FT was an adapted Léger and Boucher test (ALBT) and was conducted on a 400 m tartan field marked-off every 50 m with pylons. Ventilatory data were collected every 15 s using a portable telemetric system (Cosmed K2, JFB International, Italy). The LT was performed on an adapted treadmill (Sopur, Germany) and ventilatory data were collected every minute using a breath-by-breath automated system (CPX, Medical Graphics, MN, USA). The LT and the FT were not significantly different for duration (8 min 50 +/- 1 min 24 vs 9 min 55 +/- 29 s), percentage of maximal heart rate (HR, 86.2 +/- 3.9 vs 89.7 +/- 5.3%), maximal minute ventilation (VE, 101.6 +/- 28.5 vs 96.8 +/- 28.2 1.min(-1)) and peak oxygen uptake (VO2 peak, 39.7 + 7.3 vs 36.1 + 5.8 ml.kg(-1).min(-1) assessed with the CPX and the K2, respectively. We concluded that the FT proposed in the present study is a valid test for direct VO2 peak assessment in wheelchair athletes using a portable VO2 telemetric system. Nonetheless, the Léger and Mercier model equation did not accurately predict VO2 max and further investigation is needed to determine a valid VO2 max prediction equation for these subjects during the FT.

Utilization of Airborne and in Situ Data Obtained in SGP99, SMEX02, CLASIC and SMAPVEX08 Field Campaigns for SMAP Soil Moisture Algorithm Development and Validation

NASA Technical Reports Server (NTRS)

Colliander, Andreas; Chan, Steven; Yueh, Simon; Cosh, Michael; Bindlish, Rajat; Jackson, Tom; Njoku, Eni

2010-01-01

Field experiment data sets that include coincident remote sensing measurements and in situ sampling will be valuable in the development and validation of the soil moisture algorithms of the NASA's future SMAP (Soil Moisture Active and Passive) mission. This paper presents an overview of the field experiment data collected from SGP99, SMEX02, CLASIC and SMAPVEX08 campaigns. Common in these campaigns were observations of the airborne PALS (Passive and Active L- and S-band) instrument, which was developed to acquire radar and radiometer measurements at low frequencies. The combined set of the PALS measurements and ground truth obtained from all these campaigns was under study. The investigation shows that the data set contains a range of soil moisture values collected under a limited number of conditions. The quality of both PALS and ground truth data meets the needs of the SMAP algorithm development and validation. The data set has already made significant impact on the science behind SMAP mission. The areas where complementing of the data would be most beneficial are also discussed.

MR-based measurements and simulations of the magnetic field created by a realistic transcranial magnetic stimulation (TMS) coil and stimulator.

PubMed

Mandija, Stefano; Petrov, Petar I; Neggers, Sebastian F W; Luijten, Peter R; van den Berg, Cornelis A T

2016-11-01

Transcranial magnetic stimulation (TMS) is an emerging technique that allows non-invasive neurostimulation. However, the correct validation of electromagnetic models of typical TMS coils and the correct assessment of the incident TMS field (B TMS ) produced by standard TMS stimulators are still lacking. Such a validation can be performed by mapping B TMS produced by a realistic TMS setup. In this study, we show that MRI can provide precise quantification of the magnetic field produced by a realistic TMS coil and a clinically used TMS stimulator in the region in which neurostimulation occurs. Measurements of the phase accumulation created by TMS pulses applied during a tailored MR sequence were performed in a phantom. Dedicated hardware was developed to synchronize a typical, clinically used, TMS setup with a 3-T MR scanner. For comparison purposes, electromagnetic simulations of B TMS were performed. MR-based measurements allow the mapping and quantification of B TMS starting 2.5 cm from the TMS coil. For closer regions, the intra-voxel dephasing induced by B TMS prohibits TMS field measurements. For 1% TMS output, the maximum measured value was ~0.1 mT. Simulations reflect quantitatively the experimental data. These measurements can be used to validate electromagnetic models of TMS coils, to guide TMS coil positioning, and for dosimetry and quality assessment of concurrent TMS-MRI studies without the need for crude methods, such as motor threshold, for stimulation dose determination. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluation of a multiplex PCR to identify and serotype Actinobacillus pleuropneumoniae serovars 1, 5, 7, 12 and 15.

PubMed

Turni, C; Singh, R; Schembri, M A; Blackall, P J

2014-10-01

The aim of this study was to validate a multiplex PCR for the species identification and serotyping of Actinobacillus pleuropneumoniae serovars 1, 5, 7, 12 and 15. All 15 reference strains and 411 field isolates (394 from Australia, 11 from Indonesia, five from Mexico and one from New Zealand) of A. pleuropneumoniae were tested with the multiplex PCR. The specificity of this multiplex PCR was validated on 26 non-A. pleuropneumoniae species. The multiplex PCR gave the expected results with all 15 serovar reference strains and agreed with conventional serotyping for all field isolates from serovars 1 (n = 46), 5 (n = 81), 7 (n = 80), 12 (n = 16) and serovar 15 (n = 117). In addition, a species-specific product was amplified in the multiplex PCR with all 411 A. pleuropneumoniae field isolates. Of 25 nontypeable field isolates only two did not yield a serovar-specific band in the multiplex PCR. This multiplex PCR for serovars 1, 5, 7, 12 and 15 is species specific and capable of serotyping isolates from diverse locations. Significance and impact of the study: A multiplex PCR that can recognize serovars 1, 5, 7, 12 and 15 of A. pleuropneumoniae was developed and validated. This novel diagnostic tool will enable frontline laboratories to provide key information (the serovar) to guide targeted prevention and control programmes for porcine pleuropneumonia, a serious economic disease of pigs. The previous technology, traditional serotyping, is typically provided by specialized reference laboratories, limiting the capacity to respond to this key disease. © 2014 The Society for Applied Microbiology.

Model Validation Against The Modelers’ Data Archive

DTIC Science & Technology

2014-08-01

completion of the planned Jack Rabbit 2 field trials. The relevant task for the effort addressed here is Task 4 of the current Interagency Agreement, as...readily simulates the Prairie Grass sulfur dioxide plumes. Also, Jack Rabbit II field trials are set to be completed during FY16. Once these data are...available, they will also be used to validate the combined models. This validation may prove to be more useful, as the Jack Rabbit II will release

Absolute, pressure-dependent validation of a calibration-free, airborne laser hygrometer transfer standard (SEALDH-II) from 5 to 1200 ppmv using a metrological humidity generator

NASA Astrophysics Data System (ADS)

Buchholz, Bernhard; Ebert, Volker

2018-01-01

Highly accurate water vapor measurements are indispensable for understanding a variety of scientific questions as well as industrial processes. While in metrology water vapor concentrations can be defined, generated, and measured with relative uncertainties in the single percentage range, field-deployable airborne instruments deviate even under quasistatic laboratory conditions up to 10-20 %. The novel SEALDH-II hygrometer, a calibration-free, tuneable diode laser spectrometer, bridges this gap by implementing a new holistic concept to achieve higher accuracy levels in the field. We present in this paper the absolute validation of SEALDH-II at a traceable humidity generator during 23 days of permanent operation at 15 different H2O mole fraction levels between 5 and 1200 ppmv. At each mole fraction level, we studied the pressure dependence at six different gas pressures between 65 and 950 hPa. Further, we describe the setup for this metrological validation, the challenges to overcome when assessing water vapor measurements on a high accuracy level, and the comparison results. With this validation, SEALDH-II is the first airborne, metrologically validated humidity transfer standard which links several scientific airborne and laboratory measurement campaigns to the international metrological water vapor scale.

The relationship between human field motion and preferred visible wavelengths.

PubMed

Benedict, S C; Burge, J M

1990-01-01

The purpose of this study was to investigate the relationship between human field motion and preferred visible wavelengths. The study was based on the principle of resonancy from Rogers' science of unitary human beings; 201 subjects were tested using a modified version of Ference's human field motion test (HFMT). Two matrices of color were projected to provide an environment for the measurement of preferred visible wavelengths. There was no statistically significant relationship (r = 0.0387, p = 0.293) between scores on the human field motion test and preferred visible wavelengths as measured in nanometers. The Rogerian concept of accelerated human field rhythms being coordinate with higher frequency environment patterns was not supported in this study. Questions concerning the validity of the HFMT were expressed and were based upon the ambiguity of the terminology of the instrument and the lack of understanding of the concepts used to describe human field motion. Recommendations include the use of other methods to study Rogers' framework, and the development of other instrumentation to measure human field motion.

A validity generalization procedure to test relations between intrinsic and extrinsic motivation and influence tactics.

PubMed

Barbuto, John E; Moss, Jennifer A

2006-08-01

The relations of intrinsic and extrinsic motivation with use of consultative, legitimating, and pressure influence tactics were examined using validity generalization procedures. 5 to 7 field studies with cumulative samples exceeding 800 were used to test each relationship. Significance was found for relation between agents' intrinsic motivation and their use of consultative influence tactics and agents' extrinsic motivation and their use of legitimating influence tactics.

Steps in the design, development and formative evaluation of obesity prevention-related behavior change trials.

PubMed

Baranowski, Tom; Cerin, Ester; Baranowski, Janice

2009-01-21

Obesity prevention interventions through dietary and physical activity change have generally not been effective. Limitations on possible program effectiveness are herein identified at every step in the mediating variable model, a generic conceptual framework for understanding how interventions may promote behavior change. To minimize these problems, and thereby enhance likely intervention effectiveness, four sequential types of formative studies are proposed: targeted behavior validation, targeted mediator validation, intervention procedure validation, and pilot feasibility intervention. Implementing these studies would establish the relationships at each step in the mediating variable model, thereby maximizing the likelihood that an intervention would work and its effects would be detected. Building consensus among researchers, funding agencies, and journal editors on distinct intervention development studies should avoid identified limitations and move the field forward.

Steps in the design, development and formative evaluation of obesity prevention-related behavior change trials

PubMed Central

Baranowski, Tom; Cerin, Ester; Baranowski, Janice

2009-01-01

Obesity prevention interventions through dietary and physical activity change have generally not been effective. Limitations on possible program effectiveness are herein identified at every step in the mediating variable model, a generic conceptual framework for understanding how interventions may promote behavior change. To minimize these problems, and thereby enhance likely intervention effectiveness, four sequential types of formative studies are proposed: targeted behavior validation, targeted mediator validation, intervention procedure validation, and pilot feasibility intervention. Implementing these studies would establish the relationships at each step in the mediating variable model, thereby maximizing the likelihood that an intervention would work and its effects would be detected. Building consensus among researchers, funding agencies, and journal editors on distinct intervention development studies should avoid identified limitations and move the field forward. PMID:19159476

Field Validation of the Los Angeles Motor Scale as a Tool for Paramedic Assessment of Stroke Severity.

PubMed

Kim, Joon-Tae; Chung, Pil-Wook; Starkman, Sidney; Sanossian, Nerses; Stratton, Samuel J; Eckstein, Marc; Pratt, Frank D; Conwit, Robin; Liebeskind, David S; Sharma, Latisha; Restrepo, Lucas; Tenser, May-Kim; Valdes-Sueiras, Miguel; Gornbein, Jeffrey; Hamilton, Scott; Saver, Jeffrey L

2017-02-01

The Los Angeles Motor Scale (LAMS) is a 3-item, 0- to 10-point motor stroke-deficit scale developed for prehospital use. We assessed the convergent, divergent, and predictive validity of the LAMS when performed by paramedics in the field at multiple sites in a large and diverse geographic region. We analyzed early assessment and outcome data prospectively gathered in the FAST-MAG trial (Field Administration of Stroke Therapy-Magnesium phase 3) among patients with acute cerebrovascular disease (cerebral ischemia and intracranial hemorrhage) within 2 hours of onset, transported by 315 ambulances to 60 receiving hospitals. Among 1632 acute cerebrovascular disease patients (age 70±13 years, male 57.5%), time from onset to prehospital LAMS was median 30 minutes (interquartile range 20-50), onset to early postarrival (EPA) LAMS was 145 minutes (interquartile range 119-180), and onset to EPA National Institutes of Health Stroke Scale was 150 minutes (interquartile range 120-180). Between the prehospital and EPA assessments, LAMS scores were stable in 40.5%, improved in 37.6%, and worsened in 21.9%. In tests of convergent validity, against the EPA National Institutes of Health Stroke Scale, correlations were r=0.49 for the prehospital LAMS and r=0.89 for the EPA LAMS. Prehospital LAMS scores did diverge from the prehospital Glasgow Coma Scale, r=-0.22. Predictive accuracy (adjusted C statistics) for nondisabled 3-month outcome was as follows: prehospital LAMS, 0.76 (95% confidence interval 0.74-0.78); EPA LAMS, 0.85 (95% confidence interval 0.83-0.87); and EPA National Institutes of Health Stroke Scale, 0.87 (95% confidence interval 0.85-0.88). In this multicenter, prospective, prehospital study, the LAMS showed good to excellent convergent, divergent, and predictive validity, further establishing it as a validated instrument to characterize stroke severity in the field. © 2017 American Heart Association, Inc.

Development and field validation of a regional, management-scale habitat model: A koala Phascolarctos cinereus case study.

PubMed

Law, Bradley; Caccamo, Gabriele; Roe, Paul; Truskinger, Anthony; Brassil, Traecey; Gonsalves, Leroy; McConville, Anna; Stanton, Matthew

2017-09-01

Species distribution models have great potential to efficiently guide management for threatened species, especially for those that are rare or cryptic. We used MaxEnt to develop a regional-scale model for the koala Phascolarctos cinereus at a resolution (250 m) that could be used to guide management. To ensure the model was fit for purpose, we placed emphasis on validating the model using independently-collected field data. We reduced substantial spatial clustering of records in coastal urban areas using a 2-km spatial filter and by modeling separately two subregions separated by the 500-m elevational contour. A bias file was prepared that accounted for variable survey effort. Frequency of wildfire, soil type, floristics and elevation had the highest relative contribution to the model, while a number of other variables made minor contributions. The model was effective in discriminating different habitat suitability classes when compared with koala records not used in modeling. We validated the MaxEnt model at 65 ground-truth sites using independent data on koala occupancy (acoustic sampling) and habitat quality (browse tree availability). Koala bellows ( n  = 276) were analyzed in an occupancy modeling framework, while site habitat quality was indexed based on browse trees. Field validation demonstrated a linear increase in koala occupancy with higher modeled habitat suitability at ground-truth sites. Similarly, a site habitat quality index at ground-truth sites was correlated positively with modeled habitat suitability. The MaxEnt model provided a better fit to estimated koala occupancy than the site-based habitat quality index, probably because many variables were considered simultaneously by the model rather than just browse species. The positive relationship of the model with both site occupancy and habitat quality indicates that the model is fit for application at relevant management scales. Field-validated models of similar resolution would assist in guiding management of conservation-dependent species.

Malaria surveys using rapid diagnostic tests and validation of results using post hoc quantification of Plasmodium falciparum histidine-rich protein 2.

PubMed

Plucinski, Mateusz; Dimbu, Rafael; Candrinho, Baltazar; Colborn, James; Badiane, Aida; Ndiaye, Daouda; Mace, Kimberly; Chang, Michelle; Lemoine, Jean F; Halsey, Eric S; Barnwell, John W; Udhayakumar, Venkatachalam; Aidoo, Michael; Rogier, Eric

2017-11-07

Rapid diagnostic test (RDT) positivity is supplanting microscopy as the standard measure of malaria burden at the population level. However, there is currently no standard for externally validating RDT results from field surveys. Individuals' blood concentration of the Plasmodium falciparum histidine rich protein 2 (HRP2) protein were compared to results of HRP2-detecting RDTs in participants from field surveys in Angola, Mozambique, Haiti, and Senegal. A logistic regression model was used to estimate the HRP2 concentrations corresponding to the 50 and 90% level of detection (LOD) specific for each survey. There was a sigmoidal dose-response relationship between HRP2 concentration and RDT positivity for all surveys. Variation was noted in estimates for field RDT sensitivity, with the 50% LOD ranging between 0.076 and 6.1 ng/mL and the 90% LOD ranging between 1.1 and 53 ng/mL. Surveys conducted in two different provinces of Angola using the same brand of RDT and same study methodology showed a threefold difference in LOD. Measures of malaria prevalence estimated using population RDT positivity should be interpreted in the context of potentially large variation in RDT LODs between, and even within, surveys. Surveys based on RDT positivity would benefit from external validation of field RDT results by comparing RDT positivity and antigen concentration.

Validation of Satellite Retrieved Land Surface Variables

NASA Technical Reports Server (NTRS)

Lakshmi, Venkataraman; Susskind, Joel

1999-01-01

The effective use of satellite observations of the land surface is limited by the lack of high spatial resolution ground data sets for validation of satellite products. Recent large scale field experiments include FIFE, HAPEX-Sahel and BOREAS which provide us with data sets that have large spatial coverage and long time coverage. It is the objective of this paper to characterize the difference between the satellite estimates and the ground observations. This study and others along similar lines will help us in utilization of satellite retrieved data in large scale modeling studies.

Oxygen uptake during functional activities after stroke—Reliability and validity of a portable ergospirometry system

PubMed Central

Brurok, Berit; Tjønna, Arnt Erik; Tørhaug, Tom; Askim, Torunn

2017-01-01

Background People with stroke have a low peak aerobic capacity and experience increased effort during performance of daily activities. The purpose of this study was to examine test-retest reliability of a portable ergospirometry system in people with stroke during performance of functional activities in a field-test. Secondary aims were to examine the proportion of oxygen consumed during the field-test in relation to the peak-test and to analyse the correlation between the oxygen uptake during the field-test and peak-test in order to support the validity of the field-test. Methods With simultaneous measurement of oxygen consumption, participants performed a standardized field-test consisting of five activities; walking over ground, stair walking, stepping over obstacles, walking slalom between cones and from a standing position lifting objects from one height to another. All activities were performed in self-selected speed. Prior to the field-test, a peak aerobic capacity test was performed. The field-test was repeated minimum 2 and maximum 14 days between the tests. ICC2,1 and Bland Altman tests (Limits of Agreement, LoA) were used to analyse test-retest reliability. Results In total 31 participants (39% women, mean (SD) age 54.5 (12.7) years and 21.1 (14.3) months’ post-stroke) were included. The ICC2,1 was ≥ 0.80 for absolute V̇O2, relative V̇O2, minute ventilation, CO2, respiratory exchange ratio, heart rate and Borgs rating of perceived exertion. ICC2,1 for total time to complete the field-test was 0.99. Mean difference in steady state V̇O2 during Test 1 and Test 2 was -0.40 (2.12) The LoAs were -3.75 and 4.51. Participants spent 60.7% of their V̇O2peak performing functional activities. Correlation between field-test and peak-test was 0.689, p = 0.001 for absolute and 0.733, p = 0.001 for relative V̇O2. Conclusions This study presents first evidence on reliability of oxygen uptake during performance of functional activities after stroke, showing very good test-retest reliability. The secondary analysis showed that the amount of energy spent during the field-test relative to the peak-test was high and the correlation between the two test was good, supporting the validity of this method. PMID:29065164

Comparisons of measured and calculated potential magnetic fields. [in solar corona

NASA Technical Reports Server (NTRS)

Hagyard, M. J.; Teuber, D.

1978-01-01

Photospheric line-of-sight and transverse-magnetic-field data obtained, with a vector magnetograph system for an isolated sunspot are described. A study of the linear polarization patterns and of the calculated transverse field lines indicates that the magnetic field of the region is very nearly potential. The H-alpha fibril structures of this region as seen in high-resolution photographs corroborate this conclusion. Consequently, a potential-field calculation is described using the measured line-of-sight fields together with assumed Neumann boundary conditions; both are necessary and sufficient for a unique solution. The computed transverse fields are then compared with the measured transverse fields to verify the potential-field model and assumed boundary values. The implications of these comparisons for the validity of magnetic-field extrapolations using potential theory are discussed.

Instruments to assess patients with rotator cuff pathology: a systematic review of measurement properties.

PubMed

Longo, Umile Giuseppe; Saris, Daniël; Poolman, Rudolf W; Berton, Alessandra; Denaro, Vincenzo

2012-10-01

The aims of this study were to obtain an overview of the methodological quality of studies on the measurement properties of rotator cuff questionnaires and to describe how well various aspects of the design and statistical analyses of studies on measurement properties are performed. A systematic review of published studies on the measurement properties of rotator cuff questionnaires was performed. Two investigators independently rated the quality of the studies using the Consensus-based Standards for the selection of health Measurement Instruments checklist. This checklist was developed in an international Delphi consensus study. Sixteen studies were included, in which two measurement instruments were evaluated, namely the Western Ontario Rotator Cuff Index and the Rotator Cuff Quality-of-Life Measure. The methodological quality of the included studies was adequate on some properties (construct validity, reliability, responsiveness, internal consistency, and translation) but need to be improved on other aspects. The most important methodological aspects that need to be developed are as follows: measurement error, content validity, structural validity, cross-cultural validity, criterion validity, and interpretability. Considering the importance of adequate measurement properties, it is concluded that, in the field of rotator cuff pathology, there is room for improvement in the methodological quality of studies measurement properties. II.

Mindful attention and awareness: relationships with psychopathology and emotion regulation.

PubMed

Gregório, Sónia; Pinto-Gouveia, José

2013-01-01

The growing interest in mindfulness from the scientific community has originated several self-report measures of this psychological construct. The Mindful Attention and Awareness Scale (MAAS) is a self-report measure of mindfulness at a trait-level. This paper aims at exploring MAAS psychometric characteristics and validating it for the Portuguese population. The first two studies replicate some of the original author's statistical procedures in two different samples from the Portuguese general community population, in particular confirmatory factor analyses. Results from both analyses confirmed the scale single-factor structure and indicated a very good reliability. Moreover, cross-validation statistics showed that this single-factor structure is valid for different respondents from the general community population. In the third study the Portuguese version of the MAAS was found to have good convergent and discriminant validities. Overall the findings support the psychometric validity of the Portuguese version of MAAS and suggest this is a reliable self-report measure of trait-mindfulness, a central construct in Clinical Psychology research and intervention fields.

Predicting Military Recruiter Effectiveness: A Literature Review

DTIC Science & Technology

1987-04-01

employing commanding officer nominations and/or supervisor ratings as criteria for success in recruiting. Wollack and KiDnis (1960). Commanding officer...ratings can be used to predict field recruiter performance. The authors attribute the failure to predict field recruiter performance to the...Time to Complete -12 -27 -5 -09 5. MC 431 Completion/ Failure 08 Studies 1. Cross-validities obtained via rMonte Carlo procedure by Borman, Toquam

Results from SMAP Validation Experiments 2015 and 2016

NASA Astrophysics Data System (ADS)

Colliander, A.; Jackson, T. J.; Cosh, M. H.; Misra, S.; Crow, W.; Powers, J.; Wood, E. F.; Mohanty, B.; Judge, J.; Drewry, D.; McNairn, H.; Bullock, P.; Berg, A. A.; Magagi, R.; O'Neill, P. E.; Yueh, S. H.

2017-12-01

NASA's Soil Moisture Active Passive (SMAP) mission was launched in January 2015. The objective of the mission is global mapping of soil moisture and freeze/thaw state. Well-characterized sites with calibrated in situ soil moisture measurements are used to determine the quality of the soil moisture data products; these sites are designated as core validation sites (CVS). To support the CVS-based validation, airborne field experiments are used to provide high-fidelity validation data and to improve the SMAP retrieval algorithms. The SMAP project and NASA coordinated airborne field experiments at three CVS locations in 2015 and 2016. SMAP Validation Experiment 2015 (SMAPVEX15) was conducted around the Walnut Gulch CVS in Arizona in August, 2015. SMAPVEX16 was conducted at the South Fork CVS in Iowa and Carman CVS in Manitoba, Canada from May to August 2016. The airborne PALS (Passive Active L-band Sensor) instrument mapped all experiment areas several times resulting in 30 coincidental measurements with SMAP. The experiments included intensive ground sampling regime consisting of manual sampling and augmentation of the CVS soil moisture measurements with temporary networks of soil moisture sensors. Analyses using the data from these experiments have produced various results regarding the SMAP validation and related science questions. The SMAPVEX15 data set has been used for calibration of a hyper-resolution model for soil moisture product validation; development of a multi-scale parameterization approach for surface roughness, and validation of disaggregation of SMAP soil moisture with optical thermal signal. The SMAPVEX16 data set has been already used for studying the spatial upscaling within a pixel with highly heterogeneous soil texture distribution; for understanding the process of radiative transfer at plot scale in relation to field scale and SMAP footprint scale over highly heterogeneous vegetation distribution; for testing a data fusion based soil moisture downscaling approach; and for investigating soil moisture impact on estimation of vegetation fluorescence from airborne measurements. The presentation will describe the collected data and showcase some of the most important results achieved so far.

Validation of reference genes for quantitative RT-PCR studies of gene expression in perennial ryegrass (Lolium perenne L.)

PubMed Central

2010-01-01

Background Perennial ryegrass (Lolium perenne L.) is an important pasture and turf crop. Biotechniques such as gene expression studies are being employed to improve traits in this temperate grass. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) is among the best methods available for determining changes in gene expression. Before analysis of target gene expression, it is essential to select an appropriate normalisation strategy to control for non-specific variation between samples. Reference genes that have stable expression at different biological and physiological states can be effectively used for normalisation; however, their expression stability must be validated before use. Results Existing Serial Analysis of Gene Expression data were queried to identify six moderately expressed genes that had relatively stable gene expression throughout the year. These six candidate reference genes (eukaryotic elongation factor 1 alpha, eEF1A; TAT-binding protein homolog 1, TBP-1; eukaryotic translation initiation factor 4 alpha, eIF4A; YT521-B-like protein family protein, YT521-B; histone 3, H3; ubiquitin-conjugating enzyme, E2) were validated for qRT-PCR normalisation in 442 diverse perennial ryegrass (Lolium perenne L.) samples sourced from field- and laboratory-grown plants under a wide range of experimental conditions. Eukaryotic EF1A is encoded by members of a multigene family exhibiting differential expression and necessitated the expression analysis of different eEF1A encoding genes; a highly expressed eEF1A (h), a moderately, but stably expressed eEF1A (s), and combined expression of multigene eEF1A (m). NormFinder identified eEF1A (s) and YT521-B as the best combination of two genes for normalisation of gene expression data in perennial ryegrass following different defoliation management in the field. Conclusions This study is unique in the magnitude of samples tested with the inclusion of numerous field-grown samples, helping pave the way to conduct gene expression studies in perennial biomass crops under field-conditions. From our study several stably expressed reference genes have been validated. This provides useful candidates for reference gene selection in perennial ryegrass under conditions other than those tested here. PMID:20089196

Hygrothermal Material Properties for Soils in Building Science

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

Kehrer, Manfred; Pallin, Simon B.

2017-01-01

Hygrothermal performance of soils coupled to buildings is complicated because of the dearth of information on soil properties. However they are important when numerical simulation of coupled heat and moisture transport for below-grade building components are performed as their temperature and moisture content has an influence on the durability of the below-grade building component. Soils can be classified by soil texture. According to the Unified Soil Classification System (USCA), 12 different soils can be defined on the basis of three soil components: clay, sand, and silt. This study shows how existing material properties for typical American soils can be transferredmore » and used for the calculation of the coupled heat and moisture transport of building components in contact with soil. Furthermore a thermal validation with field measurements under known boundary conditions is part of this study, too. Field measurements for soil temperature and moisture content for two specified soils are carried out right now under known boundary conditions. As these field measurements are not finished yet, the full hygrothermal validation is still missing« less

Application and Testing the Reliability and Validity of a Modified Version of Herek's Attitudes Toward Lesbians and Gay Men Scale in China

PubMed Central

Yu, Yong; Xiang, Ying

2011-01-01

The present study was the first attempt to test the reliability and validity of Herek's Attitudes Toward Lesbians and Gay Men Scale (ATLG; Herek, 1988) in the Chinese population. Participants (n = 2,391 for the field trials and n = 200 for test–retest reliability) were asked to complete the translated, slightly modified version of the ATLG. The resulting ATLG has a two-dimensional factor structure as well as good validity and reliability in the Chinese culture. ATLG scores followed distinct patterns according sex and level of education that were consistent with previous studies in other populations. The significance of these findings in Chinese culture is discussed. PMID:21294029

Design of shared instruments to utilize simulated gravities generated by a large-gradient, high-field superconducting magnet.

PubMed

Wang, Y; Yin, D C; Liu, Y M; Shi, J Z; Lu, H M; Shi, Z H; Qian, A R; Shang, P

2011-03-01

A high-field superconducting magnet can provide both high-magnetic fields and large-field gradients, which can be used as a special environment for research or practical applications in materials processing, life science studies, physical and chemical reactions, etc. To make full use of a superconducting magnet, shared instruments (the operating platform, sample holders, temperature controller, and observation system) must be prepared as prerequisites. This paper introduces the design of a set of sample holders and a temperature controller in detail with an emphasis on validating the performance of the force and temperature sensors in the high-magnetic field.

Design of shared instruments to utilize simulated gravities generated by a large-gradient, high-field superconducting magnet

NASA Astrophysics Data System (ADS)

Wang, Y.; Yin, D. C.; Liu, Y. M.; Shi, J. Z.; Lu, H. M.; Shi, Z. H.; Qian, A. R.; Shang, P.

2011-03-01

A high-field superconducting magnet can provide both high-magnetic fields and large-field gradients, which can be used as a special environment for research or practical applications in materials processing, life science studies, physical and chemical reactions, etc. To make full use of a superconducting magnet, shared instruments (the operating platform, sample holders, temperature controller, and observation system) must be prepared as prerequisites. This paper introduces the design of a set of sample holders and a temperature controller in detail with an emphasis on validating the performance of the force and temperature sensors in the high-magnetic field.

Geoelectric monitoring at the Boulder magnetic observatory

USGS Publications Warehouse

Blum, Cletus; White, Tim; Sauter, Edward A.; Stewart, Duff; Bedrosian, Paul A.; Love, Jeffrey J.

2017-01-01

Despite its importance to a range of applied and fundamental studies, and obvious parallels to a robust network of magnetic-field observatories, long-term geoelectric field monitoring is rarely performed. The installation of a new geoelectric monitoring system at the Boulder magnetic observatory of the US Geological Survey is summarized. Data from the system are expected, among other things, to be used for testing and validating algorithms for mapping North American geoelectric fields. An example time series of recorded electric and magnetic fields during a modest magnetic storm is presented. Based on our experience, we additionally present operational aspects of a successful geoelectric field monitoring system.

Bigfoot Field Manual, Version 2.1

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

Campbell, J.L.; Burrows, S.; Gower, S.T.

1999-09-01

The BigFoot Project is funded by the Earth Science Enterprise to collect and organize data to be used in the National Aeronautics and Space Administration's Earth Observing System (EOS) Validation Program. The data collected by the BigFoot Project are unique in being ground-based observations coincident with satellite overpasses. In addition to collecting data, the BigFoot project will develop and test new algorithms for scaling point measurements to the same spatial scales as the EOS satellite products. This BigFoot Field Manual will be used to achieve completeness and consistency of data collected at four initial BigFoot sites and at future sitesmore » that may collect similar validation data. Therefore, validation datasets submitted to the Oak Ridge National Laboratory Distributed Active Archive Center that have been compiled in a manner consistent with the field manual will be especially valuable in the validation program.« less

Development and practical implications of the Exercise Resourcefulness Inventory.

PubMed

Fast, Hilary V; Kennett, Deborah J

2015-05-01

To determine the validity and reliability of the Exercise Resourcefulness Inventory (ERI) designed to assess the self-regulatory strategies used to promote regular exercise. In Study 1, the inventory's relationship with other established scales in the exercise behavior change field was examined. In Study 2, the test-retest reliability and predictive validity of the ERI was established by having participants from Study 1 complete the inventory a second time. Internal consistency, and convergent, discriminant, and concurrent validity were supported in both studies. The test-retest correlation of the ERI was .80. As well, participants scoring higher on the ERI in Study 1 were more likely to be at a higher stage of change in Study 2, and greater increases in exercise resourcefulness over time were predictive of advancement to higher stages of change. ERI is a reliable and valid measure to assess the self-regulatory strategies used to promote regular exercise. Facilitators may want to tailor exercise programs for individuals scoring lower in resourcefulness to prevent them from relapsing. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Development and validation of a treatment planning model for magnetic nanoparticle hyperthermia cancer therapy

NASA Astrophysics Data System (ADS)

Stigliano, Robert Vincent

The use of magnetic nanoparticles (mNPs) to induce local hyperthermia has been emerging in recent years as a promising cancer therapy, in both a stand-alone and combination treatment setting, including surgery radiation and chemotherapy. The mNP solution can be injected either directly into the tumor, or administered intravenously. Studies have shown that some cancer cells associate with, internalize, and aggregate mNPs more preferentially than normal cells, with and without antibody targeting. Once the mNPs are delivered inside the cells, a low frequency (30-300kHz) alternating electromagnetic field is used to activate the mNPs. The nanoparticles absorb the applied field and provide localized heat generation at nano-micron scales. Treatment planning models have been shown to improve treatment efficacy in radiation therapy by limiting normal tissue damage while maximizing dose to the tumor. To date, there does not exist a clinical treatment planning model for magnetic nanoparticle hyperthermia which is robust, validated, and commercially available. The focus of this research is on the development and experimental validation of a treatment planning model, consisting of a coupled electromagnetic and thermal model that predicts dynamic thermal distributions during treatment. When allowed to incubate, the mNPs are often sequestered by cancer cells and packed into endosomes. The proximity of the mNPs has a strong influence on their ability to heat due to interparticle magnetic interaction effects. A model of mNP heating which takes into account the effects of magnetic interaction was developed, and validated against experimental data. An animal study in mice was conducted to determine the effects of mNP solution injection duration and PEGylation on macroscale mNP distribution within the tumor, in order to further inform the treatment planning model and future experimental technique. In clinical applications, a critical limiting factor for the maximum applied field is the heating caused by eddy currents, which are induced in the noncancerous tissue. Phantom studies were conducted to validate the ability of the model to accurately predict eddy current heating in the case of zero blood perfusion, and preliminary data was collected to show the validity of the model in live mice to incorporate blood perfusion.

Development and Validation of Search Filters to Identify Articles on Family Medicine in Online Medical Databases.

PubMed

Pols, David H J; Bramer, Wichor M; Bindels, Patrick J E; van de Laar, Floris A; Bohnen, Arthur M

2015-01-01

Physicians and researchers in the field of family medicine often need to find relevant articles in online medical databases for a variety of reasons. Because a search filter may help improve the efficiency and quality of such searches, we aimed to develop and validate search filters to identify research studies of relevance to family medicine. Using a new and objective method for search filter development, we developed and validated 2 search filters for family medicine. The sensitive filter had a sensitivity of 96.8% and a specificity of 74.9%. The specific filter had a specificity of 97.4% and a sensitivity of 90.3%. Our new filters should aid literature searches in the family medicine field. The sensitive filter may help researchers conducting systematic reviews, whereas the specific filter may help family physicians find answers to clinical questions at the point of care when time is limited. © 2015 Annals of Family Medicine, Inc.

Infrared imaging - A validation technique for computational fluid dynamics codes used in STOVL applications

NASA Technical Reports Server (NTRS)

Hardman, R. R.; Mahan, J. R.; Smith, M. H.; Gelhausen, P. A.; Van Dalsem, W. R.

1991-01-01

The need for a validation technique for computational fluid dynamics (CFD) codes in STOVL applications has led to research efforts to apply infrared thermal imaging techniques to visualize gaseous flow fields. Specifically, a heated, free-jet test facility was constructed. The gaseous flow field of the jet exhaust was characterized using an infrared imaging technique in the 2 to 5.6 micron wavelength band as well as conventional pitot tube and thermocouple methods. These infrared images are compared to computer-generated images using the equations of radiative exchange based on the temperature distribution in the jet exhaust measured with the thermocouple traverses. Temperature and velocity measurement techniques, infrared imaging, and the computer model of the infrared imaging technique are presented and discussed. From the study, it is concluded that infrared imaging techniques coupled with the radiative exchange equations applied to CFD models are a valid method to qualitatively verify CFD codes used in STOVL applications.

LADO as a Language Test: Issues of Validity

ERIC Educational Resources Information Center

McNamara, Tim; Van Den Hazelkamp, Carolien; Verrips, Maaike

2016-01-01

This article brings together the theoretical field of language testing and the practical field of language analysis for the determination of the origin of asylum seekers. It considers what it would mean to think of language analysis as a form of language test, subject to the same validity constraints, and proposes a research agenda.

Finding Kids with Special Needs: the Background, Development, Field Test and Validation.

ERIC Educational Resources Information Center

Resource Management Systems, Inc., Carmel, CA.

Described are the development of "Findings Kids with Special Needs" (FKSN), a instrument to identify children's learning problems and gifted students; results of field testing with 24,825 children, kindergarten through grade 8, in 110 schools; and validation procedures. Discussed is test construction, including incorporation of 12…

Validation techniques for fault emulation of SRAM-based FPGAs

DOE PAGES

Quinn, Heather; Wirthlin, Michael

2015-08-07

A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA inmore » a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this study we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.« less

How much detail is needed in modeling a transcranial magnetic stimulation figure-8 coil: Measurements and brain simulations

PubMed Central

Mandija, Stefano; Sommer, Iris E. C.; van den Berg, Cornelis A. T.; Neggers, Sebastiaan F. W.

2017-01-01

Background Despite TMS wide adoption, its spatial and temporal patterns of neuronal effects are not well understood. Although progress has been made in predicting induced currents in the brain using realistic finite element models (FEM), there is little consensus on how a magnetic field of a typical TMS coil should be modeled. Empirical validation of such models is limited and subject to several limitations. Methods We evaluate and empirically validate models of a figure-of-eight TMS coil that are commonly used in published modeling studies, of increasing complexity: simple circular coil model; coil with in-plane spiral winding turns; and finally one with stacked spiral winding turns. We will assess the electric fields induced by all 3 coil models in the motor cortex using a computer FEM model. Biot-Savart models of discretized wires were used to approximate the 3 coil models of increasing complexity. We use a tailored MR based phase mapping technique to get a full 3D validation of the incident magnetic field induced in a cylindrical phantom by our TMS coil. FEM based simulations on a meshed 3D brain model consisting of five tissues types were performed, using two orthogonal coil orientations. Results Substantial differences in the induced currents are observed, both theoretically and empirically, between highly idealized coils and coils with correctly modeled spiral winding turns. Thickness of the coil winding turns affect minimally the induced electric field, and it does not influence the predicted activation. Conclusion TMS coil models used in FEM simulations should include in-plane coil geometry in order to make reliable predictions of the incident field. Modeling the in-plane coil geometry is important to correctly simulate the induced electric field and to correctly make reliable predictions of neuronal activation PMID:28640923

Guidelines for Reporting Case Studies on Extracorporeal Treatments in Poisonings: Methodology

PubMed Central

Lavergne, Valéry; Ouellet, Georges; Bouchard, Josée; Galvao, Tais; Kielstein, Jan T; Roberts, Darren M; Kanji, Salmaan; Mowry, James B; Calello, Diane P; Hoffman, Robert S; Gosselin, Sophie; Nolin, Thomas D; Goldfarb, David S; Burdmann, Emmanuel A; Dargan, Paul I; Decker, Brian Scott; Hoegberg, Lotte C; Maclaren, Robert; Megarbane, Bruno; Sowinski, Kevin M; Yates, Christopher; Mactier, Robert; Wiegand, Timothy; Ghannoum, Marc

2014-01-01

A literature review performed by the EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup highlighted deficiencies in the existing literature, especially the reporting of case studies. Although general reporting guidelines exist for case studies, there are none in the specific field of extracorporeal treatments in toxicology. Our goal was to construct and propose a checklist that systematically outlines the minimum essential items to be reported in a case study of poisoned patients undergoing extracorporeal treatments. Through a modified two-round Delphi technique, panelists (mostly chosen from the EXTRIP workgroup) were asked to vote on the pertinence of a set of items to identify those considered minimally essential for reporting complete and accurate case reports. Furthermore, independent raters validated the clarity of each selected items between each round of voting. All case reports containing data on extracorporeal treatments in poisoning published in Medline in 2011 were reviewed during the external validation rounds. Twenty-one panelists (20 from the EXTRIP workgroup and an invited expert on pharmacology reporting guidelines) participated in the modified Delphi technique. This group included journal editors and experts in nephrology, clinical toxicology, critical care medicine, emergency medicine, and clinical pharmacology. Three independent raters participated in the validation rounds. Panelists voted on a total of 144 items in the first round and 137 items in the second round, with response rates of 96.3% and 98.3%, respectively. Twenty case reports were evaluated at each validation round and the independent raters' response rate was 99.6% and 98.8% per validation round. The final checklist consists of 114 items considered essential for case study reporting. This methodology of alternate voting and external validation rounds was useful in developing the first reporting guideline for case studies in the field of extracorporeal treatments in poisoning. We believe that this guideline will improve the completeness and transparency of published case reports and that the systematic aggregation of information from case reports may provide early signals of effectiveness and/or harm, thereby improving healthcare decision-making. PMID:24890576

Use of psi(alpha)-ETOs in the unified treatment of electronic attraction, electric field and electric field gradient multicenter integrals of screened Coulomb potentials over Slater orbitals.

PubMed

Guseinov, Israfil

2004-02-01

In this study, using complete orthonormal sets of Psi(alpha)-ETOs (where alpha=1, 0, -1, -2, ...) introduced by the author, a large number of series expansion formulae for the multicenter electronic attraction (EA), electric field (EF) and electric field gradient (EFG) integrals of the Yukawa-like screened Coulomb potentials (SCPs) is presented through the new central and noncentral potentials and the overlap integrals with the same screening constants. The final results obtained are valid for arbitrary locations of STOs and their parameters.

Field evaluation of modified asphalt binder guidelines : [brief].

DOT National Transportation Integrated Search

2014-04-01

This project assessed the suitability of Wisconsins asphalt binder modification guidelines. It follows up on a previous Wisconsin Highway Research Program (WHRP) study (0092-03-13) which served as an initial step towards validating WisDOTs asph...

Communication Problems in Requirements Engineering: A Field Study

NASA Technical Reports Server (NTRS)

Al-Rawas, Amer; Easterbrook, Steve

1996-01-01

The requirements engineering phase of software development projects is characterized by the intensity and importance of communication activities. During this phase, the various stakeholders must be able to communicate their requirements to the analysts, and the analysts need to be able to communicate the specifications they generate back to the stakeholders for validation. This paper describes a field investigation into the problems of communication between disparate communities involved in the requirements specification activities. The results of this study are discussed in terms of their relation to three major communication barriers: (1) ineffectiveness of the current communication channels; (2) restrictions on expressiveness imposed by notations; and (3) social and organizational barriers. The results confirm that organizational and social issues have great influence on the effectiveness of communication. They also show that in general, end-users find the notations used by software practitioners to model their requirements difficult to understand and validate.

Influence of magnetic field configuration on magnetohydrodynamic waves in Earth's core

NASA Astrophysics Data System (ADS)

Knezek, Nicholas; Buffett, Bruce

2018-04-01

We develop a numerical model to study magnetohydrodynamic waves in a thin layer of stratified fluid near the surface of Earth's core. Past studies have been limited to using simple background magnetic field configurations. However, the choice of field distribution can dramatically affect the structure and frequency of the waves. To permit a more general treatment of background magnetic field and layer stratification, we combine finite volume and Fourier methods to describe the wave motions. We validate our model by comparisons to previous studies and examine the influence of background magnetic field configuration on two types of magnetohydrodynamic waves. We show that the structure of zonal Magnetic-Archimedes-Coriolis (MAC) waves for a dipole background field is unstable to small perturbations of the field strength in the equatorial region. Modifications to the wave structures are computed for a range of field configurations. In addition, we show that non-zonal MAC waves are trapped near the equator for realistic magnetic field distributions, and that their latitudinal extent depends upon the distribution of magnetic field strength at the CMB.

Are secondary data sources on the neighbourhood food environment accurate? Case-study in Glasgow, UK.

PubMed

Cummins, Steven; Macintyre, Sally

2009-12-01

To assess the validity of a publicly available list of food stores through field observations of their existence, in order to contribute to research on neighbourhood food environments and health. All multiple-owned supermarkets, and a 1 in 8 sample of other food outlets, listed in 1997 and 2007 in the public register of food premises held by Glasgow City Council, Scotland, were visited to establish whether they were trading as foodstores. Postcode sectors in which foodstores were located were classified into least, middling and most deprived neighbourhoods. In total, 325 listed foodstores were visited in 1997 and 508 in 2007. Of these 87% and 88%, respectively, were trading as foodstores. There was a very slight gradient in validity by deprivation, with validity higher in least deprived neighbourhoods, though this was not statistically significant. There was reasonable, but not perfect, agreement between the list of food premises and field observations, with nearly 1 in 9 of sampled foodstores not present on the ground. Since the use of inaccurate secondary data sources may affect estimates of relationships between the neighbourhood food environment and health, further work is required to establish the validity of such data in different contexts.

Testing the Accuracy of Data-driven MHD Simulations of Active Region Evolution and Eruption

NASA Astrophysics Data System (ADS)

Leake, J. E.; Linton, M.; Schuck, P. W.

2017-12-01

Models for the evolution of the solar coronal magnetic field are vital for understanding solar activity, yet the best measurements of the magnetic field lie at the photosphere, necessitating the recent development of coronal models which are "data-driven" at the photosphere. Using magnetohydrodynamic simulations of active region formation and our recently created validation framework we investigate the source of errors in data-driven models that use surface measurements of the magnetic field, and derived MHD quantities, to model the coronal magnetic field. The primary sources of errors in these studies are the temporal and spatial resolution of the surface measurements. We will discuss the implications of theses studies for accurately modeling the build up and release of coronal magnetic energy based on photospheric magnetic field observations.

Experimental Identification of Electric Field Excitation Mechanisms in a Structural Transition of Tokamak Plasmas

PubMed Central

Kobayashi, T.; Itoh, K.; Ido, T.; Kamiya, K.; Itoh, S.-I.; Miura, Y.; Nagashima, Y.; Fujisawa, A.; Inagaki, S.; Ida, K.; Hoshino, K.

2016-01-01

Self-regulation between structure and turbulence, which is a fundamental process in the complex system, has been widely regarded as one of the central issues in modern physics. A typical example of that in magnetically confined plasmas is the Low confinement mode to High confinement mode (L-H) transition, which is intensely studied for more than thirty years since it provides a confinement improvement necessary for the realization of the fusion reactor. An essential issue in the L-H transition physics is the mechanism of the abrupt “radial” electric field generation in toroidal plasmas. To date, several models for the L-H transition have been proposed but the systematic experimental validation is still challenging. Here we report the systematic and quantitative model validations of the radial electric field excitation mechanism for the first time, using a data set of the turbulence and the radial electric field having a high spatiotemporal resolution. Examining time derivative of Poisson’s equation, the sum of the loss-cone loss current and the neoclassical bulk viscosity current is found to behave as the experimentally observed radial current that excites the radial electric field within a few factors of magnitude. PMID:27489128

Validation and Parameter Sensitivity Tests for Reconstructing Swell Field Based on an Ensemble Kalman Filter

PubMed Central

Wang, Xuan; Tandeo, Pierre; Fablet, Ronan; Husson, Romain; Guan, Lei; Chen, Ge

2016-01-01

The swell propagation model built on geometric optics is known to work well when simulating radiated swells from a far located storm. Based on this simple approximation, satellites have acquired plenty of large samples on basin-traversing swells induced by fierce storms situated in mid-latitudes. How to routinely reconstruct swell fields with these irregularly sampled observations from space via known swell propagation principle requires more examination. In this study, we apply 3-h interval pseudo SAR observations in the ensemble Kalman filter (EnKF) to reconstruct a swell field in ocean basin, and compare it with buoy swell partitions and polynomial regression results. As validated against in situ measurements, EnKF works well in terms of spatial–temporal consistency in far-field swell propagation scenarios. Using this framework, we further address the influence of EnKF parameters, and perform a sensitivity analysis to evaluate estimations made under different sets of parameters. Such analysis is of key interest with respect to future multiple-source routinely recorded swell field data. Satellite-derived swell data can serve as a valuable complementary dataset to in situ or wave re-analysis datasets. PMID:27898005

Field analysis for explosives: TNT and RDX

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

Elcoate, W.; Mapes, J.

The EPA has listed as hazardous many of the compounds used in the production of ammunitions and other explosive ordnance. The contamination of soil with TNT (2,4,6-trinitrotoluene), the major component of many munitions formulations and to a lesser degree RDX (hexhydro-1,3,5-trinitro-1,3,5-trizine) is a significant problem at many ammunition manufacturing facilities, depots, and ordnance disposal sites. Field test kits for explosives TNT and RDX (hexhydro-1,3,5-trinitro-1,3,5-triazine) were developed based on the methods of T.F. Jenkins and M.E. Walsh and T.F Jenkins. EnSys Environmental Products, Inc. with technical support from T.F. Jenkins took the original TNT procedure, modified it for easier field use,more » performed validation studies to ensure that it met or exceeded the method specifications for both the T.F. Jenkins and SW-846 methods, and developed an easy to use test format for the field testing of TNT. The RDX procedure has gone through the development cycle and is presently in the field validation phase. This paper describes the test protocol and performance characteristics of the TNT test procedure.« less

Field Demonstration and Validation of a New Device for Measuring Groundwater and Perchlorate Fluxes at IHDIV-NSWC, Indian Head, MD

DTIC Science & Technology

2006-07-01

in bioremediation (such as lactate, citrate, benzoate , phenols, etc). Site Study Objectives • demonstrate and validate the PFM as an innovative...contaminants and alcohol tracers. However, organic acids (e.g., benzoate ) can be used as the PFM resident racers. We modified zeolites and GAC with a...bioremediation (such as lactate, citrate, benzoate , phenols, etc). 1.2. Objectives of the Demonstration The specific objectives of this

Modelling the impacts of reoccurring fires in tropical savannahs using Biome-BGC.

NASA Astrophysics Data System (ADS)

Fletcher, Charlotte; Petritsch, Richard; Pietsch, Stephan

2010-05-01

Fires are a dominant feature of tropical savannahs and have occurred throughout history by natural as well as human-induced means. These fires have a profound influence on the landscape in terms of flux dynamics and vegetative species composition. This study attempts to understand the impacts of fire regimes on flux dynamics and vegetation composition in savannahs using the Biome-BGC model. The Batéké Plateau, Gabon - an area of savannah grasslands in the Congo basin, serves as a case-study. To achieve model validation for savannahs, data sets from stands with differing levels of past burning are used. It is hypothesised that the field measurements from those stands with lower-levels of past burning will correlate with the Biome-BGC model output, meaning that the model is validated for the savannah excluding fire regimes. However, in reality, fire is frequent in the savannah. Data on past fire events are available from the Moderate Resolution Imaging Spectroradiometer (MODIS) to provide the fire regimes of the model. As the field data-driven measurements of the burnt stands are influenced by fire in the savannah, this will therefore result in a Biome-BGC model validated for the impacts of fire on savannah ecology. The validated model can then be used to predict the savannah's flux dynamics under the fire scenarios expected with climate and/or human impact change.

Incremental Validity of Useful Field of View Subtests for the Prediction of Instrumental Activities of Daily Living

PubMed Central

Aust, Frederik; Edwards, Jerri D.

2015-01-01

Introduction The Useful Field of View Test (UFOV®) is a cognitive measure that predicts older adults’ ability to perform a range of everyday activities. However, little is known about the individual contribution of each subtest to these predictions and the underlying constructs of UFOV performance remain a topic of debate. Method We investigated the incremental validity of UFOV subtests for the prediction of Instrumental Activities of Daily Living (IADL) performance in two independent datasets, the SKILL (n = 828) and ACTIVE (n = 2426) studies. We, then, explored the cognitive and visual abilities assessed by UFOV using a range of neuropsychological and vision tests administered in the SKILL study. Results In the four subtest variant of UFOV, only subtests 2 and 3 consistently made independent contributions to the prediction of IADL performance across three different behavioral measures. In all cases, the incremental validity of UFOV subtests 1 and 4 was negligible. Furthermore, we found that UFOV was related to processing speed, general non-speeded cognition, and visual function; the omission of subtests 1 and 4 from the test score did not affect these associations. Conclusions UFOV subtests 1 and 4 appear to be of limited use to predict IADL and possibly other everyday activities. Future experimental research should investigate if shortening the UFOV by omitting these subtests is a reliable and valid assessment approach. PMID:26782018

Assessment of physical activity with the Computer Science and Applications, Inc., accelerometer: laboratory versus field validation.

PubMed

Nichols, J F; Morgan, C G; Chabot, L E; Sallis, J F; Calfas, K J

2000-03-01

Our purpose was to compare the validity of the Computer Science and Applications, (CSA) Inc., accelerometer in laboratory and field settings and establish CSA count ranges for light, moderate, and vigorous physical activity. Validity was determined in 60 adults during treadmill exercise, using oxygen consumption (VO2) as the criterion measure, while 30 adults walked and jogged outdoors on a 400-m track. The relationship between CSA counts and VO2 was linear (R2 = .89 SEE = 3.72 ml.kg-1.min-1), as was the relationship between velocity and counts in the field (R2 = .89, SEE = 0.89 mi.hr-1). However, significant differences were found (p < .05) between laboratory and field measures of CSA counts for light and vigorous intensity. We conclude that the CSA can be used to quantify walking and jogging outdoors on level ground; however, laboratory equations may not be appropriate for use in field settings, particularly for light and vigorous activity.

Hybrid particle-field molecular dynamics simulation for polyelectrolyte systems.

PubMed

Zhu, You-Liang; Lu, Zhong-Yuan; Milano, Giuseppe; Shi, An-Chang; Sun, Zhao-Yan

2016-04-14

To achieve simulations on large spatial and temporal scales with high molecular chemical specificity, a hybrid particle-field method was proposed recently. This method is developed by combining molecular dynamics and self-consistent field theory (MD-SCF). The MD-SCF method has been validated by successfully predicting the experimentally observable properties of several systems. Here we propose an efficient scheme for the inclusion of electrostatic interactions in the MD-SCF framework. In this scheme, charged molecules are interacting with the external fields that are self-consistently determined from the charge densities. This method is validated by comparing the structural properties of polyelectrolytes in solution obtained from the MD-SCF and particle-based simulations. Moreover, taking PMMA-b-PEO and LiCF3SO3 as examples, the enhancement of immiscibility between the ion-dissolving block and the inert block by doping lithium salts into the copolymer is examined by using the MD-SCF method. By employing GPU-acceleration, the high performance of the MD-SCF method with explicit treatment of electrostatics facilitates the simulation study of many problems involving polyelectrolytes.

Simulation of gaseous pollutant dispersion around an isolated building using the k-ω SST (shear stress transport) turbulence model.

PubMed

Yu, Hesheng; Thé, Jesse

2017-05-01

The dispersion of gaseous pollutant around buildings is complex due to complex turbulence features such as flow detachment and zones of high shear. Computational fluid dynamics (CFD) models are one of the most promising tools to describe the pollutant distribution in the near field of buildings. Reynolds-averaged Navier-Stokes (RANS) models are the most commonly used CFD techniques to address turbulence transport of the pollutant. This research work studies the use of [Formula: see text] closure model for the gas dispersion around a building by fully resolving the viscous sublayer for the first time. The performance of standard [Formula: see text] model is also included for comparison, along with results of an extensively validated Gaussian dispersion model, the U.S. Environmental Protection Agency (EPA) AERMOD (American Meteorological Society/U.S. Environmental Protection Agency Regulatory Model). This study's CFD models apply the standard [Formula: see text] and the [Formula: see text] turbulence models to obtain wind flow field. A passive concentration transport equation is then calculated based on the resolved flow field to simulate the distribution of pollutant concentrations. The resultant simulation of both wind flow and concentration fields are validated rigorously by extensive data using multiple validation metrics. The wind flow field can be acceptably modeled by the [Formula: see text] model. However, the [Formula: see text] model fails to simulate the gas dispersion. The [Formula: see text] model outperforms [Formula: see text] in both flow and dispersion simulations, with higher hit rates for dimensionless velocity components and higher "factor of 2" of observations (FAC2) for normalized concentration. All these validation metrics of [Formula: see text] model pass the quality assurance criteria recommended by The Association of German Engineers (Verein Deutscher Ingenieure, VDI) guideline. Furthermore, these metrics are better than or the same as those in the literature. Comparison between the performances of [Formula: see text] and AERMOD shows that the CFD simulation is superior to Gaussian-type model for pollutant dispersion in the near wake of obstacles. AERMOD can perform as a screening tool for near-field gas dispersion due to its expeditious calculation and the ability to handle complicated cases. The utilization of [Formula: see text] to simulate gaseous pollutant dispersion around an isolated building is appropriate and is expected to be suitable for complex urban environment. Multiple validation metrics of [Formula: see text] turbulence model in CFD quantitatively indicated that this turbulence model was appropriate for the simulation of gas dispersion around buildings. CFD is, therefore, an attractive alternative to wind tunnel for modeling gas dispersion in urban environment due to its excellent performance, and lower cost.

Contributions of poroelastic-wave potentials to seismoelectromagnetic wavefields and validity of the quasi-static calculation: a view from a borehole model

NASA Astrophysics Data System (ADS)

Guan, Wei; Shi, Peng; Hu, Hengshan

2018-01-01

In this study, we theoretically analyse the contributions of the four poroelastic-wave potentials to seismoelectromagnetic (SEM) wavefields, verify the validity of the quasi-static calculation of the electric field and provide a method to calculate the magnetic field by using the curl-free electric field. Calculations show that both the fast and slow P waves and the SH and SV waves have non-negligible contributions to the SEM fields. The S waves have indirect contribution to the electric field through the EM conversion from the magnetic field, although the direct contribution due to streaming current is negligible if EM wavenumbers are much smaller than those of the S waves. The P waves have indirect contribution to the magnetic field through EM conversion from the electric field, although the direct contribution is absent. The quasi-static calculation of the electric field is practicable since it is normally satisfied in reality that the EM wavenumbers are much smaller than those of poroelastic waves. While the direct contribution of the S waves and the higher-order EM conversions are ignored, the first-order EM conversion from the S-wave-induced magnetic field is reserved through the continuity of the electric-current density. To calculate the magnetic field on this basis, we separate the quasi-static electric field into a rotational and an irrotational part. The magnetic-field solutions are derived through Hertz vectors in which the coefficients of the magnetic Hertz vector are determined from the magnetic-field continuities and those of the electric Hertz vector originate from the irrotational part of the quasi-static electric field.

Evaluating Mixed Research Studies: A Mixed Methods Approach

ERIC Educational Resources Information Center

Leech, Nancy L.; Dellinger, Amy B.; Brannagan, Kim B.; Tanaka, Hideyuki

2010-01-01

The purpose of this article is to demonstrate application of a new framework, the validation framework (VF), to assist researchers in evaluating mixed research studies. Based on an earlier work by Dellinger and Leech, a description of the VF is delineated. Using the VF, three studies from education, health care, and counseling fields are…

Research Areas in Adult and Continuing Education

ERIC Educational Resources Information Center

Zawacki-Richter, Olaf; Röbken, Heinke; Ehrenspeck-Kolasa, Yvonne; von Ossietzky, Carl

2014-01-01

This study builds upon a Delphi study carried out by Zawacki-Richter (2009) which posited a validated classification of research areas in the special area of distance education. We now replicate the study for the broader field of adult and continuing education (ACE). The aims of this paper are: firstly, to develop a categorisation of research…

Acoustic characterization of high intensity focused ultrasound fields generated from a transmitter with a large aperture

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

Chen, Tao; Fan, Tingbo; Jiangsu Province Institute for Medical Equipment Testing, Nanjing 210012

Prediction and measurement of the acoustic field emitted from a high intensity focused ultrasound (HIFU) is essential for the accurate ultrasonic treatment. In this study, the acoustic field generated from a strongly focused HIFU transmitter was characterized by a combined experiment and simulation method. The spheroidal beam equation (SBE) was utilized to describe the nonlinear sound propagation. The curve of the source pressure amplitude versus voltage excitation was determined by fitting the measured ratio of the second harmonic to the fundamental component of the focal waveform to the simulation result; finally, the acoustic pressure field generated by the strongly focusedmore » HIFU transmitter was predicted by using the SBE model. A commercial fiber optic probe hydrophone was utilized to measure the acoustic pressure field generated from a 1.1 MHz HIFU transmitter with a large half aperture angle of 30°. The maximum measured peak-to-peak pressure was up to 72 MPa. The validity of this combined approach was confirmed by the comparison between the measured results and the calculated ones. The results indicate that the current approach might be useful to describe the HIFU field. The results also suggest that this method is not valid for low excitations owing to low sensitivity of the second harmonic.« less

Development of Chemistry Triangle Oriented Module on Topic of Reaction Rate for Senior High School Level Grade XI Chemistry Learning.

NASA Astrophysics Data System (ADS)

Sari, D. R.; Hardeli; Bayharti

2018-04-01

This study aims to produce chemistry triangle oriented module on topic of reaction rate, and to reveal the validity and practicality level of the generated module. The type of research used is EducationalDesign Research (EDR) with development model is Plompmodel. This model consists of three phases, which are preliminary research, prototyping phase, and assessment phase. The instrument used in this research is questionnaire validity and practicality. The data of the research were analyzed by using Kappa Cohen formula. The chemistry triangle oriented module validation sheet was given to 5 validators consisting of 3 chemistry lecturers and 2 high school chemistry teachers, while the practicality sheet was given to 2 chemistry teachers, 6 students of SMAN 10 Padang grade XII MIA 5 on the small groupevaluation and 25 students of SMAN 10 Padang grade XII MIA 6 on the field test. Based on the questionnaire validity analysis, the validity level of the module is very high with the value of kappa moment 0.87. The level of practicality based on teacher questionnaire response is very high category with a kappa moment value 0.96. Based on the questionnaire of student responses on small group evaluation, the level of practicality is very high category with a kappa moment 0.81, and the practicality is very high category with kappa moment value 0.83 based on questionnaire of student response on field test.

The Effects of Magnetic Nozzle Configurations on Plasma Thrusters

NASA Technical Reports Server (NTRS)

Turchi, P. J.

1997-01-01

Over the course of eight years, the Ohio State University has performed research in support of electric propulsion development efforts at the NASA Lewis Research Center, Cleveland, OH. This research has been largely devoted to plasma propulsion systems including MagnetoPlasmaDynamic (MPD) thrusters with externally-applied, solenoidal magnetic fields, hollow cathodes, and Pulsed Plasma Microthrusters (PPT's). Both experimental and theoretical work has been performed, as documented in four master's theses, two doctoral dissertations, and numerous technical papers. The present document is the final report for the grant period 5 December 1987 to 31 December 1995, and summarizes all activities. Detailed discussions of each area of activity are provided in appendices: Appendix 1 - Experimental studies of magnetic nozzle effects on plasma thrusters; Appendix 2 - Numerical modeling of applied-field MPD thrusters; Appendix 3 - Theoretical and experimental studies of hollow cathodes; and Appendix 4 -Theoretical, numerical and experimental studies of pulsed plasma thrusters. Especially notable results include the efficacy of using a solenoidal magnetic field downstream of a plasma thruster to collimate the exhaust flow, the development of a new understanding of applied-field MPD thrusters (based on experimentally-validated results from state-of-the art, numerical simulation) leading to predictions of improved performance, an experimentally-validated, first-principles model for orificed, hollow-cathode behavior, and the first time-dependent, two-dimensional calculations of ablation-fed, pulsed plasma thrusters.

A systematic review on the quality, validity and usefulness of current cost-effectiveness studies for treatments of neovascular age-related macular degeneration.

PubMed

Elshout, Mari; Webers, Carroll A B; van der Reis, Margriet I; Schouten, Jan S A G

2018-06-04

Ophthalmologists increasingly depend on new drugs to advance their treatment options. These options are limited by restraints on reimbursements for new and expensive drugs. These restraints are put in place through health policy decisions based on cost-effectiveness analyses (CEA). Cost-effectiveness analyses need to be valid and of good quality to support correct decisions to create new treatment opportunities. In this study, we report the quality, validity and usefulness of CEAs for therapies for nAMD. A systematic review in PubMed, EMBASE and Cochrane was performed to include CEAs. Quality and validity assessment was based on current general quality criteria and on elements that are specific to the field of ophthalmology. Forty-eight CEAs were included in the review. Forty-four CEAs did not meet four basic model quality and validity criteria specific to CEAs in the field of ophthalmology (both eyes analysed instead of one; a time horizon extending beyond 4 years; extrapolating VA and treatment intervals beyond trial data realistically; and including the costs of low-vision). Four CEAs aligned with the quality and validity criteria. In two of these CEAs bevacizumab as-needed (PRN) was more cost-effective than bevacizumab monthly; aflibercept (VIEW); or ranibizumab monthly or PRN. In two CEAs, ranibizumab (PRN or treat and extent) was dominant over aflibercept. In two other CEAs, aflibercept was either more cost-effective or dominant over ranibizumab monthly or PRN. Two of the CEAs of sufficient quality and validity show that bevacizumab PRN is the most cost-effective treatment. Comparing ranibizumab and aflibercept, either treatment can be more cost-effective depending on the assumptions used for drug prices and treatment frequencies. The majority of the published CEAs are of insufficient quality and validity. They wrongly inform decision-makers at the cost of opportunities for ophthalmologists to treat patients. As such, they may negatively influence overall patient outcomes and societal costs. For future ophthalmic treatments, CEAs need to be improved and only published when they are of sufficient quality and validity. © 2018 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Validation of DESS as a DNA Preservation Method for the Detection of Strongyloides spp. in Canine Feces.

PubMed

Beknazarova, Meruyert; Millsteed, Shelby; Robertson, Gemma; Whiley, Harriet; Ross, Kirstin

2017-06-09

Strongyloides stercoralis is a gastrointestinal parasitic nematode with a life cycle that includes free-living and parasitic forms. For both clinical (diagnostic) and environmental evaluation, it is important that we can detect Strongyloides spp. in both human and non-human fecal samples. Real-time PCR is the most feasible method for detecting the parasite in both clinical and environmental samples that have been preserved. However, one of the biggest challenges with PCR detection is DNA degradation during the postage time from rural and remote areas to the laboratory. This study included a laboratory assessment and field validation of DESS (dimethyl sulfoxide, disodium EDTA, and saturated NaCl) preservation of Strongyloides spp. DNA in fecal samples. The laboratory study investigated the capacity of 1:1 and 1:3 sample to DESS ratios to preserve Strongyloides ratti in spike canine feces. It was found that both ratios of DESS significantly prevented DNA degradation compared to the untreated sample. This method was then validated by applying it to the field-collected canine feces and detecting Strongyloides DNA using PCR. A total of 37 canine feces samples were collected and preserved in the 1:3 ratio (sample: DESS) and of these, 17 were positive for Strongyloides spp. The study shows that both 1:1 and 1:3 sample to DESS ratios were able to preserve the Strongyloides spp. DNA in canine feces samples stored at room temperature for up to 56 days. This DESS preservation method presents the most applicable and feasible method for the Strongyloides DNA preservation in field-collected feces.

Initial validation of two opiate craving questionnaires the obsessive compulsive drug use scale and the desires for drug questionnaire.

PubMed

Franken, Ingmar H A; Hendriksa, Vincent M; van den Brink, Wim

2002-01-01

In the present study, the factor structure, internal consistency, and the concurrent validity of two heroin craving questionnaires are examined. The Desires for Drug Questionnaire (DDQ) measures three factors: desire and intention, negative reinforcement, and control. The Obsessive Compulsive Drug Use Scale (OCDUS) also measures three factors: thoughts about heroin and interference, desire and control, and resistance to thoughts and intention. Subjects were 102 Dutch patients who were currently in treatment for drug dependency. All proposed scales have good reliability and concurrent validity. Implementation of these instruments in both clinical and research field is advocated.

Validation of a Measure of Family Resilience among Iraq and Afghanistan Veterans.

PubMed

Finley, Erin P; Pugh, Mary Jo; Palmer, Raymond F

2016-01-01

Although interactions within veterans' families may support or inhibit resilient coping to stress and trauma across the deployment cycle, research on family resilience has been hampered by the lack of a brief assessment. Using a three-stage mixed-method study, we developed and conducted preliminary validation of a measure of family resilience tailored for Iraq and Afghanistan veterans (IAV), the Family Resilience Scale for Veterans (FRS-V) , which was field-tested using a survey of 151 IAV. Our findings indicate the resulting 6-item measure shows strong initial reliability and validity and support the application of existing models of family resilience in this population.

Validation of a Measure of Family Resilience among Iraq and Afghanistan Veterans

PubMed Central

Finley, Erin P.; Pugh, Mary Jo; Palmer, Raymond F.

2016-01-01

Although interactions within veterans’ families may support or inhibit resilient coping to stress and trauma across the deployment cycle, research on family resilience has been hampered by the lack of a brief assessment. Using a three-stage mixed-method study, we developed and conducted preliminary validation of a measure of family resilience tailored for Iraq and Afghanistan veterans (IAV), the Family Resilience Scale for Veterans (FRS-V), which was field-tested using a survey of 151 IAV. Our findings indicate the resulting 6-item measure shows strong initial reliability and validity and support the application of existing models of family resilience in this population. PMID:28168094

A systematic review of the reliability and validity of discrete choice experiments in valuing non-market environmental goods.

PubMed

Rakotonarivo, O Sarobidy; Schaafsma, Marije; Hockley, Neal

2016-12-01

While discrete choice experiments (DCEs) are increasingly used in the field of environmental valuation, they remain controversial because of their hypothetical nature and the contested reliability and validity of their results. We systematically reviewed evidence on the validity and reliability of environmental DCEs from the past thirteen years (Jan 2003-February 2016). 107 articles met our inclusion criteria. These studies provide limited and mixed evidence of the reliability and validity of DCE. Valuation results were susceptible to small changes in survey design in 45% of outcomes reporting reliability measures. DCE results were generally consistent with those of other stated preference techniques (convergent validity), but hypothetical bias was common. Evidence supporting theoretical validity (consistency with assumptions of rational choice theory) was limited. In content validity tests, 2-90% of respondents protested against a feature of the survey, and a considerable proportion found DCEs to be incomprehensible or inconsequential (17-40% and 10-62% respectively). DCE remains useful for non-market valuation, but its results should be used with caution. Given the sparse and inconclusive evidence base, we recommend that tests of reliability and validity are more routinely integrated into DCE studies and suggest how this might be achieved. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Validation of the Land-Surface Energy Budget and Planetary Boundary Layer for Several Intensive field Experiments

NASA Technical Reports Server (NTRS)

Bosilovich, Michael G.; Schubert, Siegfried; Molod, Andrea; Houser, Paul R.

1999-01-01

Land-surface processes in a data assimilation system influence the lower troposphere and must be properly represented. With the recent incorporation of the Mosaic Land-surface Model (LSM) into the GEOS Data Assimilation System (DAS), the detailed land-surface processes require strict validation. While global data sources can identify large-scale systematic biases at the monthly timescale, the diurnal cycle is difficult to validate. Moreover, global data sets rarely include variables such as evaporation, sensible heat and soil water. Intensive field experiments, on the other hand, can provide high temporal resolution energy budget and vertical profile data for sufficiently long periods, without global coverage. Here, we evaluate the GEOS DAS against several intensive field experiments. The field experiments are First ISLSCP Field Experiment (FIFE, Kansas, summer 1987), Cabauw (as used in PILPS, Netherlands, summer 1987), Atmospheric Radiation Measurement (ARM, Southern Great Plains, winter and summer 1998) and the Surface Heat Budget of the Arctic Ocean (SHEBA, Arctic ice sheet, winter and summer 1998). The sites provide complete surface energy budget data for periods of at least one year, and some periods of vertical profiles. This comparison provides a detailed validation of the Mosaic LSM within the GEOS DAS for a variety of climatologic and geographic conditions.

Kinematics, influence functions and field quantities for disturbance propagation from moving disturbance sources

NASA Technical Reports Server (NTRS)

Das, A.

1984-01-01

A unified method is presented for deriving the influence functions of moving singularities which determine the field quantities in aerodynamics and aeroacoustics. The moving singularities comprise volume and surface distributions having arbitrary orientations in space and to the trajectory. Hence one generally valid formula for the influence functions which reveal some universal relationships and remarkable properties in the disturbance fields. The derivations used are completely consistent with the physical processes in the propagation field, such that treatment renders new descriptions for some standard concepts. The treatment is uniformly valid for subsonic and supersonic Mach numbers.

Early Childhood Special Education and Early Intervention Personnel Preparation Standards of the Division for Early Childhood: Field Validation

ERIC Educational Resources Information Center

Cochran, Deborah C.; Gallagher, Peggy A.; Stayton, Vicki D.; Dinnebeil, Laurie A.; Lifter, Karin; Chandler, Lynette K.; Christensen, Kimberly A.

2012-01-01

Results of the field validation survey of the revised initial and new advanced Council for Exceptional Children (CEC) Division for Early Childhood (DEC) early childhood special education (ECSE)/early intervention (EI) personnel standards are presented. Personnel standards are used as part of educational accountability systems and in teacher…

The Fast Scattering Code (FSC): Validation Studies and Program Guidelines

NASA Technical Reports Server (NTRS)

Tinetti, Ana F.; Dunn, Mark H.

2011-01-01

The Fast Scattering Code (FSC) is a frequency domain noise prediction program developed at the NASA Langley Research Center (LaRC) to simulate the acoustic field produced by the interaction of known, time harmonic incident sound with bodies of arbitrary shape and surface impedance immersed in a potential flow. The code uses the equivalent source method (ESM) to solve an exterior 3-D Helmholtz boundary value problem (BVP) by expanding the scattered acoustic pressure field into a series of point sources distributed on a fictitious surface placed inside the actual scatterer. This work provides additional code validation studies and illustrates the range of code parameters that produce accurate results with minimal computational costs. Systematic noise prediction studies are presented in which monopole generated incident sound is scattered by simple geometric shapes - spheres (acoustically hard and soft surfaces), oblate spheroids, flat disk, and flat plates with various edge topologies. Comparisons between FSC simulations and analytical results and experimental data are presented.

Breath-collection device for delayed breath-alcohol analysis

DOT National Transportation Integrated Search

1980-12-01

The report includes the details of a study to develop, evaluate, and validate a breath collection device (BCD) for delayed breath-alcohol analysis. Primary applications of the BCD include collection of breath-alcohol samples for field surveys or for ...

Field study evaluation of cepstrum coefficient speech analysis for fatigue in aviation cabin crew.

DOT National Transportation Integrated Search

2013-10-01

Impaired neurobehavioral performance induced by fatigue may compromise safety in 24-hr operational : environmentssuch as aviation. As such, non-invasive, reliable, and valid methods of objectively detecting : compromised performance capacity in opera...

Validating soil denitrification models based on laboratory N_{2} and N_{2}O fluxes and underlying processes derived by stable isotope approaches

NASA Astrophysics Data System (ADS)

Well, Reinhard; Böttcher, Jürgen; Butterbach-Bahl, Klaus; Dannenmann, Michael; Deppe, Marianna; Dittert, Klaus; Dörsch, Peter; Horn, Marcus; Ippisch, Olaf; Mikutta, Robert; Müller, Carsten; Müller, Christoph; Senbayram, Mehmet; Vogel, Hans-Jörg; Wrage-Mönnig, Nicole

2016-04-01

Robust denitrification data suitable to validate soil N2 fluxes in denitrification models are scarce due to methodical limitations and the extreme spatio-temporal heterogeneity of denitrification in soils. Numerical models have become essential tools to predict denitrification at different scales. Model performance could either be tested for total gaseous flux (NO + N2O + N2), individual denitrification products (e.g. N2O and/or NO) or for the effect of denitrification factors (e.g. C-availability, respiration, diffusivity, anaerobic volume, etc.). While there are numerous examples for validating N2O fluxes, there are neither robust field data of N2 fluxes nor sufficiently resolved measurements of control factors used as state variables in the models. To the best of our knowledge there has been only one published validation of modelled soil N2 flux by now, using a laboratory data set to validate an ecosystem model. Hence there is a need for validation data at both, the mesocosm and the field scale including validation of individual denitrification controls. Here we present the concept for collecting model validation data which is be part of the DFG-research unit "Denitrification in Agricultural Soils: Integrated Control and Modelling at Various Scales (DASIM)" starting this year. We will use novel approaches including analysis of stable isotopes, microbial communities, pores structure and organic matter fractions to provide denitrification data sets comprising as much detail on activity and regulation as possible as a basis to validate existing and calibrate new denitrification models that are applied and/or developed by DASIM subprojects. The basic idea is to simulate "field-like" conditions as far as possible in an automated mesocosm system without plants in order to mimic processes in the soil parts not significantly influenced by the rhizosphere (rhizosphere soils are studied by other DASIM projects). Hence, to allow model testing in a wide range of conditions, denitrification control factors will be varied in the initial settings (pore volume, plant residues, mineral N, pH) but also over time, where moisture, temperature, and mineral N will be manipulated according to typical time patterns in the field. This will be realized by including precipitation events, fertilization (via irrigation), drainage (via water potential) and temperature in the course of incubations. Moreover, oxygen concentration will be varied to simulate anaerobic events. These data will be used to calibrate the newly to develop DASIM models as well as existing denitrification models. One goal of DASIM is to create a public data base as a joint basis for model testing by denitrification modellers. Therefore we invite contributions of suitable data-sets from the scientific community. Requirements will be briefly outlined.

Experimental Pressure Measurements on Hydropower Turbine Runners

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

Harding, Samuel F.; Richmond, Marshall C.

The range of hydrodynamic operating conditions to which the turbine is exposed results in significant pressure fluctuations on both the pressure and suction sides of the blades. Understanding these dynamic pressures has a range of applications. Structurally, the resulting dynamic loads are significant in understanding the design life and maintenance schedule of the bearing, shafts and runner components. The pulsing pressures have also been seen to have a detrimental effect on the surface condition of the blades. Biologically, the pressure gradients and pressure extremes are the primary driver of barotrauma for fish passing through hydroturbines. Improvements in computational fluid dynamicsmore » (CFD) can be used to simulate such unsteady pressures in the regions of concern. High frequency model scale and prototype measurements of pressures at the blade are important in the validation of these models. Experimental characterization of pressure fields over hydroturbine blades has been demonstrated by a number of studies which using multiple pressure transducers to map the pressure contours on the runner blades. These have been performed at both model and prototype scales, often to validate computational models of the pressure and flow fields over the blades. This report provides a review of existing studies in which the blade pressure was measured in situ. The report assesses the technology for both model and prototype scale testing. The details of the primary studies in this field are reported and used to inform the types of hardware required for similar experiments based on the Ice Harbor Dam owned by the US Corps of Engineers on the Snake River, WA, USA. Such a study would be used to validate the CFD performed for the BioPA.« less

Validating the WRF-Chem model for wind energy applications using High Resolution Doppler Lidar data from a Utah 2012 field campaign

NASA Astrophysics Data System (ADS)

Mitchell, M. J.; Pichugina, Y. L.; Banta, R. M.

2015-12-01

Models are important tools for assessing potential of wind energy sites, but the accuracy of these projections has not been properly validated. In this study, High Resolution Doppler Lidar (HRDL) data obtained with high temporal and spatial resolution at heights of modern turbine rotors were compared to output from the WRF-chem model in order to help improve the performance of the model in producing accurate wind forecasts for the industry. HRDL data were collected from January 23-March 1, 2012 during the Uintah Basin Winter Ozone Study (UBWOS) field campaign. A model validation method was based on the qualitative comparison of the wind field images, time-series analysis and statistical analysis of the observed and modeled wind speed and direction, both for case studies and for the whole experiment. To compare the WRF-chem model output to the HRDL observations, the model heights and forecast times were interpolated to match the observed times and heights. Then, time-height cross-sections of the HRDL and WRF-Chem wind speed and directions were plotted to select case studies. Cross-sections of the differences between the observed and forecasted wind speed and directions were also plotted to visually analyze the model performance in different wind flow conditions. A statistical analysis includes the calculation of vertical profiles and time series of bias, correlation coefficient, root mean squared error, and coefficient of determination between two datasets. The results from this analysis reveals where and when the model typically struggles in forecasting winds at heights of modern turbine rotors so that in the future the model can be improved for the industry.

Measuring Neighborhood Walkable Environments: A Comparison of Three Approaches

PubMed Central

Chiang, Yen-Cheng; Sullivan, William; Larsen, Linda

2017-01-01

Multiple studies have revealed the impact of walkable environments on physical activity. Scholars attach considerable importance to leisure and health-related walking. Recent studies have used Google Street View as an instrument to assess city streets and walkable environments; however, no study has compared the validity of Google Street View assessments of walkable environment attributes to assessments made by local residents and compiled from field visits. In this study, we involved nearby residents and compared the extent to which Google Street View assessments of the walkable environment correlated with assessments from local residents and with field visits. We determined the assessment approaches (local resident or field visit assessments) that exhibited the highest agreement with Google Street View. One city with relatively high-quality walkable environments and one city with relatively low-quality walkable environments were examined, and three neighborhoods from each city were surveyed. Participants in each neighborhood used one of three approaches to assess the walkability of the environment: 15 local residents assessed the environment using a map, 15 participants made a field visit to assess the environment, and 15 participants used Google Street View to assess the environment, yielding a total of 90 valid samples for the two cities. Findings revealed that the three approaches to assessing neighborhood walkability were highly correlated for traffic safety, aesthetics, sidewalk quality, and physical barriers. Compared with assessments from participants making field visits, assessments by local residents were more highly correlated with Google Street View assessments. Google Street View provides a more convenient, low-cost, efficient, and safe approach to assess neighborhood walkability. The results of this study may facilitate future large-scale walkable environment surveys, effectively reduce expenses, and improve survey efficiency. PMID:28587186

Insight into the structural requirements of proton pump inhibitors based on CoMFA and CoMSIA studies.

PubMed

Nayana, M Ravi Shashi; Sekhar, Y Nataraja; Nandyala, Haritha; Muttineni, Ravikumar; Bairy, Santosh Kumar; Singh, Kriti; Mahmood, S K

2008-10-01

In the present study, a series of 179 quinoline and quinazoline heterocyclic analogues exhibiting inhibitory activity against Gastric (H+/K+)-ATPase were investigated using the comparative molecular field analysis (CoMFA) and comparative molecular similarity indices (CoMSIA) methods. Both the models exhibited good correlation between the calculated 3D-QSAR fields and the observed biological activity for the respective training set compounds. The most optimal CoMFA and CoMSIA models yielded significant leave-one-out cross-validation coefficient, q(2) of 0.777, 0.744 and conventional cross-validation coefficient, r(2) of 0.927, 0.914 respectively. The predictive ability of generated models was tested on a set of 52 compounds having broad range of activity. CoMFA and CoMSIA yielded predicted activities for test set compounds with r(pred)(2) of 0.893 and 0.917 respectively. These validation tests not only revealed the robustness of the models but also demonstrated that for our models r(pred)(2) based on the mean activity of test set compounds can accurately estimate external predictivity. The factors affecting activity were analyzed carefully according to standard coefficient contour maps of steric, electrostatic, hydrophobic, acceptor and donor fields derived from the CoMFA and CoMSIA. These contour plots identified several key features which explain the wide range of activities. The results obtained from models offer important structural insight into designing novel peptic-ulcer inhibitors prior to their synthesis.

The Use of Virtual Reality in the Study of People's Responses to Violent Incidents.

PubMed

Rovira, Aitor; Swapp, David; Spanlang, Bernhard; Slater, Mel

2009-01-01

This paper reviews experimental methods for the study of the responses of people to violence in digital media, and in particular considers the issues of internal validity and ecological validity or generalisability of results to events in the real world. Experimental methods typically involve a significant level of abstraction from reality, with participants required to carry out tasks that are far removed from violence in real life, and hence their ecological validity is questionable. On the other hand studies based on field data, while having ecological validity, cannot control multiple confounding variables that may have an impact on observed results, so that their internal validity is questionable. It is argued that immersive virtual reality may provide a unification of these two approaches. Since people tend to respond realistically to situations and events that occur in virtual reality, and since virtual reality simulations can be completely controlled for experimental purposes, studies of responses to violence within virtual reality are likely to have both ecological and internal validity. This depends on a property that we call 'plausibility' - including the fidelity of the depicted situation with prior knowledge and expectations. We illustrate this with data from a previously published experiment, a virtual reprise of Stanley Milgram's 1960s obedience experiment, and also with pilot data from a new study being developed that looks at bystander responses to violent incidents.

The Use of Virtual Reality in the Study of People's Responses to Violent Incidents

PubMed Central

Rovira, Aitor; Swapp, David; Spanlang, Bernhard; Slater, Mel

2009-01-01

This paper reviews experimental methods for the study of the responses of people to violence in digital media, and in particular considers the issues of internal validity and ecological validity or generalisability of results to events in the real world. Experimental methods typically involve a significant level of abstraction from reality, with participants required to carry out tasks that are far removed from violence in real life, and hence their ecological validity is questionable. On the other hand studies based on field data, while having ecological validity, cannot control multiple confounding variables that may have an impact on observed results, so that their internal validity is questionable. It is argued that immersive virtual reality may provide a unification of these two approaches. Since people tend to respond realistically to situations and events that occur in virtual reality, and since virtual reality simulations can be completely controlled for experimental purposes, studies of responses to violence within virtual reality are likely to have both ecological and internal validity. This depends on a property that we call ‘plausibility’ – including the fidelity of the depicted situation with prior knowledge and expectations. We illustrate this with data from a previously published experiment, a virtual reprise of Stanley Milgram's 1960s obedience experiment, and also with pilot data from a new study being developed that looks at bystander responses to violent incidents. PMID:20076762

Discriminant Analysis of Defective and Non-Defective Field Pea (Pisum sativum L.) into Broad Market Grades Based on Digital Image Features.

PubMed

McDonald, Linda S; Panozzo, Joseph F; Salisbury, Phillip A; Ford, Rebecca

2016-01-01

Field peas (Pisum sativum L.) are generally traded based on seed appearance, which subjectively defines broad market-grades. In this study, we developed an objective Linear Discriminant Analysis (LDA) model to classify market grades of field peas based on seed colour, shape and size traits extracted from digital images. Seeds were imaged in a high-throughput system consisting of a camera and laser positioned over a conveyor belt. Six colour intensity digital images were captured (under 405, 470, 530, 590, 660 and 850nm light) for each seed, and surface height was measured at each pixel by laser. Colour, shape and size traits were compiled across all seed in each sample to determine the median trait values. Defective and non-defective seed samples were used to calibrate and validate the model. Colour components were sufficient to correctly classify all non-defective seed samples into correct market grades. Defective samples required a combination of colour, shape and size traits to achieve 87% and 77% accuracy in market grade classification of calibration and validation sample-sets respectively. Following these results, we used the same colour, shape and size traits to develop an LDA model which correctly classified over 97% of all validation samples as defective or non-defective.

Discriminant Analysis of Defective and Non-Defective Field Pea (Pisum sativum L.) into Broad Market Grades Based on Digital Image Features

PubMed Central

McDonald, Linda S.; Panozzo, Joseph F.; Salisbury, Phillip A.; Ford, Rebecca

2016-01-01

Field peas (Pisum sativum L.) are generally traded based on seed appearance, which subjectively defines broad market-grades. In this study, we developed an objective Linear Discriminant Analysis (LDA) model to classify market grades of field peas based on seed colour, shape and size traits extracted from digital images. Seeds were imaged in a high-throughput system consisting of a camera and laser positioned over a conveyor belt. Six colour intensity digital images were captured (under 405, 470, 530, 590, 660 and 850nm light) for each seed, and surface height was measured at each pixel by laser. Colour, shape and size traits were compiled across all seed in each sample to determine the median trait values. Defective and non-defective seed samples were used to calibrate and validate the model. Colour components were sufficient to correctly classify all non-defective seed samples into correct market grades. Defective samples required a combination of colour, shape and size traits to achieve 87% and 77% accuracy in market grade classification of calibration and validation sample-sets respectively. Following these results, we used the same colour, shape and size traits to develop an LDA model which correctly classified over 97% of all validation samples as defective or non-defective. PMID:27176469

Fear of cancer recurrence: a systematic literature review of self-report measures.

PubMed

Thewes, Belinda; Butow, Phillis; Zachariae, Robert; Christensen, Soren; Simard, Sébastien; Gotay, Carolyn

2012-06-01

Prior research has shown that many cancer survivors experience ongoing fears of cancer recurrence (FCR) and that this chronic uncertainty of health status during and after cancer treatment can be a significant psychological burden. The field of research on FCR is an emerging area of investigation in the cancer survivorship literature, and several standardised instruments for its assessment have been developed. This review aims to identify all available FCR-specific questionnaires and subscales and critically appraise their properties. A systematic review was undertaken to identify instruments measuring FCR. Relevant studies were identified via Medline (1950-2010), CINAHL (1982-2010), PsycINFO (1967-2010) and AMED (1985-2010) databases, reference lists of articles and reviews, grey literature databases and consultation with experts in the field. The Medical Outcomes Trust criteria were used to examine the psychometric properties of the questionnaires. A total of 20 relevant multi-item measures were identified. The majority of instruments have demonstrated reliability and preliminary evidence of validity. Relatively few brief measures (2-10 items) were found to have comprehensive validation and reliability data available. Several valid and reliable longer measures (>10 items) are available. Three have developed short forms that may prove useful as screening tools. This analysis indicated that further refinement and validation of existing instruments is required. Valid and reliable instruments are needed for both research and clinical care. Copyright © 2011 John Wiley & Sons, Ltd.

Identification and Validation of ESP Teacher Competencies: A Research Design

ERIC Educational Resources Information Center

Venkatraman, G.; Prema, P.

2013-01-01

The paper presents the research design used for identifying and validating a set of competencies required of ESP (English for Specific Purposes) teachers. The identification of the competencies and the three-stage validation process are also discussed. The observation of classes of ESP teachers for field-testing the validated competencies and…

Reliability, validity and administrative burden of the community reintegration of injured service members computer adaptive test (CRIS-CAT)".

PubMed

Resnik, Linda; Borgia, Matthew; Ni, Pensheng; Pirraglia, Paul A; Jette, Alan

2012-09-17

The Computer Adaptive Test version of the Community Reintegration of Injured Service Members measure (CRIS-CAT) consists of three scales measuring Extent of, Perceived Limitations in, and Satisfaction with community integration. The CRIS-CAT was developed using item response theory methods. The purposes of this study were to assess the reliability, concurrent, known group and predictive validity and respondent burden of the CRIS-CAT.The CRIS-CAT was developed using item response theory methods. The purposes of this study were to assess the reliability, concurrent, known group and predictive validity and respondent burden of the CRIS-CAT. This was a three-part study that included a 1) a cross-sectional field study of 517 homeless, employed, and Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Veterans; who completed all items in the CRIS item set, 2) a cohort study with one year follow-up study of 135 OEF/OIF Veterans, and 3) a 50-person study of CRIS-CAT administration. Conditional reliability of simulated CAT scores was calculated from the field study data, and concurrent validity and known group validity were examined using Pearson product correlations and ANOVAs. Data from the cohort were used to examine the ability of the CRIS-CAT to predict key one year outcomes. Data from the CRIS-CAT administration study were used to calculate ICC (2,1) minimum detectable change (MDC), and average number of items used during CAT administration. Reliability scores for all scales were above 0.75, but decreased at both ends of the score continuum. CRIS-CAT scores were correlated with concurrent validity indicators and differed significantly between the three Veteran groups (P < .001). The odds of having any Emergency Room visits were reduced for Veterans with better CRIS-CAT scores (Extent, Perceived Satisfaction respectively: OR = 0.94, 0.93, 0.95; P < .05). CRIS-CAT scores were predictive of SF-12 physical and mental health related quality of life scores at the 1 year follow-up. Scales had ICCs >0.9. MDCs were 5.9, 6.2, and 3.6, respectively for Extent, Perceived and Satisfaction subscales. Number of items (mn, SD) administered at Visit 1 were 14.6 (3.8) 10.9 (2.7) and 10.4 (1.7) respectively for Extent, Perceived and Satisfaction subscales. The CRIS-CAT demonstrated sound measurement properties including reliability, construct, known group and predictive validity, and it was administered with minimal respondent burden. These findings support the use of this measure in assessing community reintegration.

Large-scale experimental technology with remote sensing in land surface hydrology and meteorology

NASA Technical Reports Server (NTRS)

Brutsaert, Wilfried; Schmugge, Thomas J.; Sellers, Piers J.; Hall, Forrest G.

1988-01-01

Two field experiments to study atmospheric and land surface processes and their interactions are summarized. The Hydrologic-Atmospheric Pilot Experiment, which tested techniques for measuring evaporation, soil moisture storage, and runoff at scales of about 100 km, was conducted over a 100 X 100 km area in France from mid-1985 to early 1987. The first International Satellite Land Surface Climatology Program field experiment was conducted in 1987 to develop and use relationships between current satellite measurements and hydrologic, climatic, and biophysical variables at the earth's surface and to validate these relationships with ground truth. This experiment also validated surface parameterization methods for simulation models that describe surface processes from the scale of vegetation leaves up to scales appropriate to satellite remote sensing.

Acquisition and Analysis of NASA Ames Sunphotometer Measurements during SAGE III Validation Campaigns and other Tropospheric and Stratospheric Research Missions

NASA Technical Reports Server (NTRS)

Livingston, John M.

2004-01-01

NASA Cooperative Agreement NCC2-1251 provided funding from April 2001 through December 2003 for Mr. John Livingston of SRI International to collaborate with NASA Ames Research Center scientists and engineers in the acquisition and analysis of airborne sunphotometer measurements during various atmospheric field studies. Mr. Livingston participated in instrument calibrations at Mauna Loa Observatory, pre-mission hardware and software preparations, acquisition and analysis of sunphotometer measurements during the missions, and post-mission analysis of data and reporting of scientific findings. The atmospheric field missions included the spring 2001 Intensive of the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia), the Asian Dust Above Monterey-2003 (ADAM-2003) experiment, and the winter 2003 Second SAGE III Ozone Loss and Validation Experiment (SOLVE II).

PSI-Center Simulations of Validation Platform Experiments

NASA Astrophysics Data System (ADS)

Nelson, B. A.; Akcay, C.; Glasser, A. H.; Hansen, C. J.; Jarboe, T. R.; Marklin, G. J.; Milroy, R. D.; Morgan, K. D.; Norgaard, P. C.; Shumlak, U.; Victor, B. S.; Sovinec, C. R.; O'Bryan, J. B.; Held, E. D.; Ji, J.-Y.; Lukin, V. S.

2013-10-01

The Plasma Science and Innovation Center (PSI-Center - http://www.psicenter.org) supports collaborating validation platform experiments with extended MHD simulations. Collaborators include the Bellan Plasma Group (Caltech), CTH (Auburn U), FRX-L (Los Alamos National Laboratory), HIT-SI (U Wash - UW), LTX (PPPL), MAST (Culham), Pegasus (U Wisc-Madison), PHD/ELF (UW/MSNW), SSX (Swarthmore College), TCSU (UW), and ZaP/ZaP-HD (UW). Modifications have been made to the NIMROD, HiFi, and PSI-Tet codes to specifically model these experiments, including mesh generation/refinement, non-local closures, appropriate boundary conditions (external fields, insulating BCs, etc.), and kinetic and neutral particle interactions. The PSI-Center is exploring application of validation metrics between experimental data and simulations results. Biorthogonal decomposition is proving to be a powerful method to compare global temporal and spatial structures for validation. Results from these simulation and validation studies, as well as an overview of the PSI-Center status will be presented.

Development and Validation of a Gender Ideology Scale for Family Planning Services in Rural China

PubMed Central

Yang, Xueyan; Li, Shuzhuo; Feldman, Marcus W.

2013-01-01

The objectives of this study are to develop a scale of gender role ideology appropriate for assessing Quality of Care in family planning services for rural China. Literature review, focus-group discussions and in-depth interviews with service providers and clients from two counties in eastern and western China, as well as experts’ assessments, were used to develop a scale for family planning services. Psychometric methodologies were applied to samples of 601 service clients and 541 service providers from a survey in a district in central China to validate its internal consistency, reliability, and construct validity with realistic and strategic dimensions. This scale is found to be reliable and valid, and has prospects for application both academically and practically in the field. PMID:23573222

Experimental Investigation of Inlet Distortion in a Multistage Axial Compressor

NASA Astrophysics Data System (ADS)

Rusu, Razvan

The primary objective of this research is to present results and methodologies used to study total pressure inlet distortion in a multi-stage axial compressor environment. The study was performed at the Purdue 3-Stage Axial Compressor Facility (P3S) which models the final three stages of a production turbofan engine's high-pressure compressor (HPC). The goal of this study was twofold; first, to design, implement, and validate a circumferentially traversable total pressure inlet distortion generation system, and second, to demonstrate data acquisition methods to characterize the inter-stage total pressure flow fields to study the propagation and attenuation of a one-per-rev total pressure distortion. The datasets acquired for this study are intended to support the development and validation of novel computational tools and flow physics models for turbomachinery flow analysis. Total pressure inlet distortion was generated using a series of low-porosity wire gauze screens placed upstream of the compressor in the inlet duct. The screens are mounted to a rotatable duct section that can be precisely controlled. The P3S compressor features fixed instrumentation stations located at the aerodynamic interface plane (AIP) and downstream and upstream of each vane row. Furthermore, the compressor features individually indexable stator vanes which can be traverse by up to two vane passages. Using a series of coordinated distortion and vane traverses, the total pressure flow field at the AIP and subsequent inter-stage stations was characterized with a high circumferential resolution. The uniformity of the honeycomb carrier was demonstrated by characterizing the flow field at the AIP while no distortion screens where installed. Next, the distortion screen used for this study was selected following three iterations of porosity reduction. The selected screen consisted of a series of layered screens with a 100% radial extent and a 120° circumferential extent. A detailed total pressure flow field characterization of the AIP was performed using the selected screen at nominal, low, and high compressor loading. Thermal anemometry was used to characterize the spatial variation in turbulence intensity at the AIP in an effort to further define inlet boundary conditions for future computational investigations. Two data acquisition methods for the study of distortion propagation and attenuation were utilized in this study. The first method approximated the bulk flow through each vane passage using a single rake measurement positioned near the center of the passage. All vane passages were measured virtually by rotating the distortion upstream by an increment equal to one vane passage. This method proved successful in tracking the distortion propagation and attenuation from the AIP up until the compressor exit. A second, more detailed, inter-stage flow field characterization method was used that generated a total pressure field with a circumferential resolution of 880 increments, or one every 0.41°. The resulting fields demonstrated the importance of secondary flows in the propagation of a total pressure distortion at the different loading conditions investigated. A second objective of this research was to document proposals and design efforts to outfit the existing P3S research compressor with a strain gage telemetry system. The purpose of this system is to validate and supplement existing blade tip timing data on the embedded rotor stage to support the development and validation of novel aeromechanical analysis tools. Integration strategies and telemetry considerations are discussed based on proposals and consultation provided by suppliers.

Field determination and QSPR prediction of equilibrium-status soil/vegetation partition coefficient of PCDD/Fs.

PubMed

Li, Li; Wang, Qiang; Qiu, Xinghua; Dong, Yian; Jia, Shenglan; Hu, Jianxin

2014-07-15

Characterizing pseudo equilibrium-status soil/vegetation partition coefficient KSV, the quotient of respective concentrations in soil and vegetation of a certain substance at remote background areas, is essential in ecological risk assessment, however few previous attempts have been made for field determination and developing validated and reproducible structure-based estimates. In this study, KSV was calculated based on measurements of seventeen 2,3,7,8-substituted PCDD/F congeners in soil and moss (Dicranum angustum), and rouzi grass (Thylacospermum caespitosum) of two background sites, Ny-Ålesund of the Arctic and Zhangmu-Nyalam region of the Tibet Plateau, respectively. By both fugacity modeling and stepwise regression of field data, the air-water partition coefficient (KAW) and aqueous solubility (SW) were identified as the influential physicochemical properties. Furthermore, validated quantitative structure-property relationship (QSPR) model was developed to extrapolate the KSV prediction to all 210 PCDD/F congeners. Molecular polarizability, molecular size and molecular energy demonstrated leading effects on KSV. Copyright © 2014 Elsevier B.V. All rights reserved.

Validating electromagnetic walking stick rail surface crack measuring systems : final report.

DOT National Transportation Integrated Search

2016-06-01

A series of field studies were undertaken to evaluate electromagnetic walking stick systems and their ability to measure the depth : of damage from surface breaking cracks. In total, four railroads, and four suppliers participated in the project. The...

Participation in Decision Making as a Property of Complex Adaptive Systems: Developing and Testing a Measure

PubMed Central

Anderson, Ruth A.; Hsieh, Pi-Ching; Su, Hui Fang; Landerman, Lawrence R.; McDaniel, Reuben R.

2013-01-01

Objectives. To (1) describe participation in decision-making as a systems-level property of complex adaptive systems and (2) present empirical evidence of reliability and validity of a corresponding measure. Method. Study 1 was a mail survey of a single respondent (administrators or directors of nursing) in each of 197 nursing homes. Study 2 was a field study using random, proportionally stratified sampling procedure that included 195 organizations with 3,968 respondents. Analysis. In Study 1, we analyzed the data to reduce the number of scale items and establish initial reliability and validity. In Study 2, we strengthened the psychometric test using a large sample. Results. Results demonstrated validity and reliability of the participation in decision-making instrument (PDMI) while measuring participation of workers in two distinct job categories (RNs and CNAs). We established reliability at the organizational level aggregated items scores. We established validity of the multidimensional properties using convergent and discriminant validity and confirmatory factor analysis. Conclusions. Participation in decision making, when modeled as a systems-level property of organization, has multiple dimensions and is more complex than is being traditionally measured. Managers can use this model to form decision teams that maximize the depth and breadth of expertise needed and to foster connection among them. PMID:24349771

Participation in decision making as a property of complex adaptive systems: developing and testing a measure.

PubMed

Anderson, Ruth A; Plowman, Donde; Corazzini, Kirsten; Hsieh, Pi-Ching; Su, Hui Fang; Landerman, Lawrence R; McDaniel, Reuben R

2013-01-01

Objectives. To (1) describe participation in decision-making as a systems-level property of complex adaptive systems and (2) present empirical evidence of reliability and validity of a corresponding measure. Method. Study 1 was a mail survey of a single respondent (administrators or directors of nursing) in each of 197 nursing homes. Study 2 was a field study using random, proportionally stratified sampling procedure that included 195 organizations with 3,968 respondents. Analysis. In Study 1, we analyzed the data to reduce the number of scale items and establish initial reliability and validity. In Study 2, we strengthened the psychometric test using a large sample. Results. Results demonstrated validity and reliability of the participation in decision-making instrument (PDMI) while measuring participation of workers in two distinct job categories (RNs and CNAs). We established reliability at the organizational level aggregated items scores. We established validity of the multidimensional properties using convergent and discriminant validity and confirmatory factor analysis. Conclusions. Participation in decision making, when modeled as a systems-level property of organization, has multiple dimensions and is more complex than is being traditionally measured. Managers can use this model to form decision teams that maximize the depth and breadth of expertise needed and to foster connection among them.

SU-E-T-219: Comprehensive Validation of the Electron Monte Carlo Dose Calculation Algorithm in RayStation Treatment Planning System for An Elekta Linear Accelerator with AgilityTM Treatment Head

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

Wang, Yi; Park, Yang-Kyun; Doppke, Karen P.

2015-06-15

Purpose: This study evaluated the performance of the electron Monte Carlo dose calculation algorithm in RayStation v4.0 for an Elekta machine with Agility™ treatment head. Methods: The machine has five electron energies (6–8 MeV) and five applicators (6×6 to 25×25 cm {sup 2}). The dose (cGy/MU at d{sub max}), depth dose and profiles were measured in water using an electron diode at 100 cm SSD for nine square fields ≥2×2 cm{sup 2} and four complex fields at normal incidence, and a 14×14 cm{sup 2} field at 15° and 30° incidence. The dose was also measured for three square fields ≥4×4more » cm{sup 2} at 98, 105 and 110 cm SSD. Using selected energies, the EBT3 radiochromic film was used for dose measurements in slab-shaped inhomogeneous phantoms and a breast phantom with surface curvature. The measured and calculated doses were analyzed using a gamma criterion of 3%/3 mm. Results: The calculated and measured doses varied by <3% for 116 of the 120 points, and <5% for the 4×4 cm{sup 2} field at 110 cm SSD at 9–18 MeV. The gamma analysis comparing the 105 pairs of in-water isodoses passed by >98.1%. The planar doses measured from films placed at 0.5 cm below a lung/tissue layer (12 MeV) and 1.0 cm below a bone/air layer (15 MeV) showed excellent agreement with calculations, with gamma passing by 99.9% and 98.5%, respectively. At the breast-tissue interface, the gamma passing rate is >98.8% at 12–18 MeV. The film results directly validated the accuracy of MU calculation and spatial dose distribution in presence of tissue inhomogeneity and surface curvature - situations challenging for simpler pencil-beam algorithms. Conclusion: The electron Monte Carlo algorithm in RayStation v4.0 is fully validated for clinical use for the Elekta Agility™ machine. The comprehensive validation included small fields, complex fields, oblique beams, extended distance, tissue inhomogeneity and surface curvature.« less

Temperature field simulation and phantom validation of a Two-armed Spiral Antenna for microwave thermotherapy.

PubMed

Du, Yongxing; Zhang, Lingze; Sang, Lulu; Wu, Daocheng

2016-04-29

In this paper, an Archimedean planar spiral antenna for the application of thermotherapy was designed. This type of antenna was chosen for its compact structure, flexible application and wide heating area. The temperature field generated by the use of this Two-armed Spiral Antenna in a muscle-equivalent phantom was simulated and subsequently validated by experimentation. First, the specific absorption rate (SAR) of the field was calculated using the Finite Element Method (FEM) by Ansoft's High Frequency Structure Simulation (HFSS). Then, the temperature elevation in the phantom was simulated by an explicit finite difference approximation of the bioheat equation (BHE). The temperature distribution was then validated by a phantom heating experiment. The results showed that this antenna had a good heating ability and a wide heating area. A comparison between the calculation and the measurement showed a fair agreement in the temperature elevation. The validated model could be applied for the analysis of electromagnetic-temperature distribution in phantoms during the process of antenna design or thermotherapy experimentation.

ALS Biomarkers for Therapy Development: State of the Field & Future Directions

PubMed Central

Benatar, Michael; Boylan, Kevin; Jeromin, Andreas; Rutkove, Seward B.; Berry, James; Atassi, Nazem; Bruijn, Lucie

2015-01-01

Biomarkers have become the focus of intense research in the field of amyotrophic lateral sclerosis (ALS), with the hope that they might aid therapy development efforts. Notwithstanding the discovery of many candidate biomarkers, none have yet emerged as validated tools for drug development. In this review we present a nuanced view of biomarkers based on the perspective of the FDA; highlight the distinction between discovery and validation; describe existing and emerging resources; review leading biological fluid-based, electrophysiological and neuroimaging candidates relevant to therapy development efforts; discuss lessons learned from biomarker initiatives in related neurodegenerative diseases; and outline specific steps that we, as a field, might take in order to hasten the development and validation of biomarkers that will prove useful in enhancing efforts to develop effective treatments for ALS patients. Most important among these perhaps is the proposal to establish a federated ALS Biomarker Consortium (ABC) in which all interested and willing stakeholders may participate with equal opportunity to contribute to the broader mission of biomarker development and validation. PMID:26574709

Perception vs. Observation, or the Contributions of Rational Choice Theory and Area Studies to Contemporary Political Science.

ERIC Educational Resources Information Center

Johnson, Chalmers

1997-01-01

Criticizes the notion that the empiricism of economics is more valid (and therefore more valuable) to the field of political science than the more subjective efforts of area studies. Specifically responds to Robert Bates's categorization of area studies as "unscientific" and unduly "humanist." Briefly discusses significant works within area…

Measurement of the gravity-field curvature by atom interferometry.

PubMed

Rosi, G; Cacciapuoti, L; Sorrentino, F; Menchetti, M; Prevedelli, M; Tino, G M

2015-01-09

We present the first direct measurement of the gravity-field curvature based on three conjugated atom interferometers. Three atomic clouds launched in the vertical direction are simultaneously interrogated by the same atom interferometry sequence and used to probe the gravity field at three equally spaced positions. The vertical component of the gravity-field curvature generated by nearby source masses is measured from the difference between adjacent gravity gradient values. Curvature measurements are of interest in geodesy studies and for the validation of gravitational models of the surrounding environment. The possibility of using such a scheme for a new determination of the Newtonian constant of gravity is also discussed.

Diagnostic validity Polish language version of the questionnaire MINI-KID (Mini International Neuropsychiatry Interview for Children and Adolescent).

PubMed

Adamowska, Sylwia; Sylwia, Adamowska; Adamowski, Tomasz; Tomasz, Adamowski; Frydecka, Dorota; Dorota, Frydecka; Kiejna, Andrzej; Andrzej, Kiejna

2014-10-01

Since over forty years structuralized interviews for clinical and epidemiological research in child and adolescent psychiatry are being developed that should increase validity and reliability of diagnoses according to classification systems (DSM and ICD). The aim of the study is to assess the validity of the Polish version of MINI-KID (Mini International Neuropsychiatric Interview for Children and Adolescents) in comparison to clinical diagnosis made by a specialist in the field of child and adolescent psychiatry. There were 140 patients included in the study (93 boys, 66.4%, mean age 11.8±3.0 and 47 girls 33.5%, mean age 14.0±2.9). All the patients were diagnosed by the specialist in the field of child and adolescent psychiatry according to ICD-10 criteria and by the independent interviewer with the Polish version of MINI-KID (version 2.0, 2001). There was higher agreement between clinical diagnoses and diagnoses based on MINI-KID interview with respect to eating disorders and externalizing disorders (κ 0.43-0.56) and lower in internalizing disorders (κ 0.13-0.45). In the clinical interview, there was smaller number of diagnostic categories (maximum 3 diagnoses per one patient) in comparison to MINI-KID (maximum 10 diagnoses per one patient), and the smaller percentage of patients with one diagnosis (65,7%) in comparison to MINI-KID interview (72%). Our study has shown satisfactory validity parameters of MINI-KID questionnaire, promoting its use for clinical and epidemiological settings. The Mini International Neuropsychiatry Interview for Children and Adolescent (MINI-KID) is the first structuralized diagnostic interview for assessing mental status in children and adolescents, which has been translated into Polish language. Our validation study demonstrated satisfactory psychometric properties of the questionnaire, enabling its use in clinical practice and in research projects. Copyright © 2014 Elsevier Inc. All rights reserved.

[External and internal validity of a multidimensional Locus of control scale of eating attitudes for athletes (LOCSCAS)].

PubMed

Paquet, Y; Scoffier, S; d'Arripe-Longueville, F

2016-10-01

In the field of health psychology, the control has consistently been considered as a protective factor. This protective role has been also highlighted in eating attitudes' domain. However, current studies use the one-dimensional scale of Rotter or the multidimensional health locus of control scale, and no specific eating attitudes' scale in the sport context exists. Moreover, the social influence in previous scales is limited. According to recent works, the purpose of this study was to test the internal and external validity of a multidimensional locus of control scale of eating attitudes for athletes. One hundred and seventy-nine participants were solicited. A confirmatory factorial analysis was conducted in order to test the internal validity of the scale. The scale external validity was tested in relation to eating attitudes. The internal validity of the scale was verified as well as the external validity, which confirmed the importance of taking into consideration social influences. Indeed, the 2 subscales "Trainers, friends" and "Parents, family" are related respectively positively and negatively in eating disorders. Copyright © 2016 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Field validation of protocols developed to evaluate in-line mastitis detection systems.

PubMed

Kamphuis, C; Dela Rue, B T; Eastwood, C R

2016-02-01

This paper reports on a field validation of previously developed protocols for evaluating the performance of in-line mastitis-detection systems. The protocols outlined 2 requirements of these systems: (1) to detect cows with clinical mastitis (CM) promptly and accurately to enable timely and appropriate treatment and (2) to identify cows with high somatic cell count (SCC) to manage bulk milk SCC levels. Gold standard measures, evaluation tests, performance measures, and performance targets were proposed. The current study validated the protocols on commercial dairy farms with automated in-line mastitis-detection systems using both electrical conductivity (EC) and SCC sensor systems that both monitor at whole-udder level. The protocol for requirement 1 was applied on 3 commercial farms. For requirement 2, the protocol was applied on 6 farms; 3 of them had low bulk milk SCC (128×10(3) cells/mL) and were the same farms as used for field evaluation of requirement 1. Three farms with high bulk milk SCC (270×10(3) cells/mL) were additionally enrolled. The field evaluation methodology and results were presented at a workshop including representation from 7 international suppliers of in-line mastitis-detection systems. Feedback was sought on the acceptance of standardized performance evaluation protocols and recommended refinements to the protocols. Although the methodology for requirement 1 was relatively labor intensive and required organizational skills over an extended period, no major issues were encountered during the field validation of both protocols. The validation, thus, proved the protocols to be practical. Also, no changes to the data collection process were recommended by the technology supplier representatives. However, 4 recommendations were made to refine the protocols: inclusion of an additional analysis that ignores small (low-density) clot observations in the definition of CM, extension of the time window from 4 to 5 milkings for timely alerts for CM, setting a maximum number of 10 milkings for the time window to detect a CM episode, and presentation of sensitivity for a larger range of false alerts per 1,000 milkings replacing minimum performance targets. The recommended refinements are discussed with suggested changes to the original protocols. The information presented is intended to inform further debate toward achieving international agreement on standard protocols to evaluate performance of in-line mastitis-detection systems. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Calculating distributed glacier mass balance for the Swiss Alps from RCM output: Development and testing of downscaling and validation methods

NASA Astrophysics Data System (ADS)

Machguth, H.; Paul, F.; Kotlarski, S.; Hoelzle, M.

2009-04-01

Climate model output has been applied in several studies on glacier mass balance calculation. Hereby, computation of mass balance has mostly been performed at the native resolution of the climate model output or data from individual cells were selected and statistically downscaled. Little attention has been given to the issue of downscaling entire fields of climate model output to a resolution fine enough to compute glacier mass balance in rugged high-mountain terrain. In this study we explore the use of gridded output from a regional climate model (RCM) to drive a distributed mass balance model for the perimeter of the Swiss Alps and the time frame 1979-2003. Our focus lies on the development and testing of downscaling and validation methods. The mass balance model runs at daily steps and 100 m spatial resolution while the RCM REMO provides daily grids (approx. 18 km resolution) of dynamically downscaled re-analysis data. Interpolation techniques and sub-grid parametrizations are combined to bridge the gap in spatial resolution and to obtain daily input fields of air temperature, global radiation and precipitation. The meteorological input fields are compared to measurements at 14 high-elevation weather stations. Computed mass balances are compared to various sets of direct measurements, including stake readings and mass balances for entire glaciers. The validation procedure is performed separately for annual, winter and summer balances. Time series of mass balances for entire glaciers obtained from the model run agree well with observed time series. On the one hand, summer melt measured at stakes on several glaciers is well reproduced by the model, on the other hand, observed accumulation is either over- or underestimated. It is shown that these shifts are systematic and correlated to regional biases in the meteorological input fields. We conclude that the gap in spatial resolution is not a large drawback, while biases in RCM output are a major limitation to model performance. The development and testing of methods to reduce regionally variable biases in entire fields of RCM output should be a focus of pursuing studies.

Automated validation of patient safety clinical incident classification: macro analysis.

PubMed

Gupta, Jaiprakash; Patrick, Jon

2013-01-01

Patient safety is the buzz word in healthcare. Incident Information Management System (IIMS) is electronic software that stores clinical mishaps narratives in places where patients are treated. It is estimated that in one state alone over one million electronic text documents are available in IIMS. In this paper we investigate the data density available in the fields entered to notify an incident and the validity of the built in classification used by clinician to categories the incidents. Waikato Environment for Knowledge Analysis (WEKA) software was used to test the classes. Four statistical classifier based on J48, Naïve Bayes (NB), Naïve Bayes Multinominal (NBM) and Support Vector Machine using radial basis function (SVM_RBF) algorithms were used to validate the classes. The data pool was 10,000 clinical incidents drawn from 7 hospitals in one state in Australia. In first part of the study 1000 clinical incidents were selected to determine type and number of fields worth investigating and in the second part another 5448 clinical incidents were randomly selected to validate 13 clinical incident types. Result shows 74.6% of the cells were empty and only 23 fields had content over 70% of the time. The percentage correctly classified classes on four algorithms using categorical dataset ranged from 42 to 49%, using free-text datasets from 65% to 77% and using both datasets from 72% to 79%. Kappa statistic ranged from 0.36 to 0.4. for categorical data, from 0.61 to 0.74. for free-text and from 0.67 to 0.77 for both datasets. Similar increases in performance in the 3 experiments was noted on true positive rate, precision, F-measure and area under curve (AUC) of receiver operating characteristics (ROC) scores. The study demonstrates only 14 of 73 fields in IIMS have data that is usable for machine learning experiments. Irrespective of the type of algorithms used when all datasets are used performance was better. Classifier NBM showed best performance. We think the classifier can be improved further by reclassifying the most confused classes and there is scope to apply text mining tool on patient safety classifications.

Adaptation and Validation of the Arabic Version of the Infant Breastfeeding Knowledge Questionnaire among Lebanese Women.

PubMed

Tamim, Hani; Ghandour, Lilian A; Shamsedine, Lama; Charafeddine, Lama; Nasser, Fatima; Khalil, Yvette; Nabulsi, Mona

2016-11-01

Valid instruments that can reliably assess maternal breastfeeding knowledge in Arabic-speaking populations are nonexistent. The availability of such an instrument is essential for investigators working in this field. This study aimed to describe the adaptation and validation of the Arabic Breastfeeding Knowledge Questionnaire (BFK-A) from the original 20-item English version. A translated version of the 20-item BFK was validated among 417 Lebanese women after pilot testing for clarity, comprehension, length, and cultural appropriateness. Exploratory factor analysis was run to examine dimensionality of the instrument and Kuder-Richardson-20 (KR-20) was used to assess its internal consistency. The BFK-A is a unidimensional scale with acceptable internal consistency reliability (KR-20 = 0.652) after the exclusion of 4 items. Higher breastfeeding knowledge levels were strongly and statistically significantly associated with higher mean scores for the validated Arabic Iowa Infant Feeding Attitude Scale ( P < .001), thus confirming its construct validity. The Arabic 16-item BFK-A has an acceptable reliability, similar to the original instrument. Further studies are encouraged to confirm the validity of the 16-item BFK-A among other Arab populations. There is also a need to develop more reliable instruments to use in lactation research in this context.

Radiation from a current filament driven by a traveling wave

NASA Technical Reports Server (NTRS)

Levine, D. M.; Meneghini, R.

1976-01-01

Solutions are presented for the electromagnetic fields radiated by an arbitrarily oriented current filament located above a perfectly conducting ground plane and excited by a traveling current wave. Both an approximate solution, valid in the fraunhofer region of the filament and predicting the radiation terms in the fields, and an exact solution, which predicts both near and far field components of the electromagnetic fields, are presented. Both solutions apply to current waveforms which propagate along the channel but are valid regardless of the actual waveshape. The exact solution is valid only for waves which propagate at the speed of light, and the approximate solution is formulated for arbitrary velocity of propagation. The spectrum-magnitude of the fourier transform-of the radiated fields is computed by assuming a compound exponential model for the current waveform. The effects of channel orientation and length, as well as velocity of propagation of the current waveform and location of the observer, are discussed. It is shown that both velocity of propagation and an effective channel length are important in determining the shape of the spectrum.

Soybean Resistance to White Mold: Evaluation of Soybean Germplasm Under Different Conditions and Validation of QTL

PubMed Central

Kandel, Ramkrishna; Chen, Charles Y.; Grau, Craig R.; Dorrance, Ann E.; Liu, Jean Q.; Wang, Yang; Wang, Dechun

2018-01-01

Soybean (Glycine max L. Merr.) white mold (SWM), caused by Sclerotinia sclerotiorum (Lib) de Barry), is a devastating fungal disease in the Upper Midwest of the United States and southern Canada. Various methods exist to evaluate for SWM resistance and many quantitative trait loci (QTL) with minor effect governing SWM resistance have been identified in prior studies. This study aimed to predict field resistance to SWM using low-cost and efficient greenhouse inoculation methods and to confirm the QTL reported in previous studies. Three related but independent studies were conducted in the field, greenhouse, and laboratory to evaluate for SWM resistance. The first study evaluated 66 soybean plant introductions (PIs) with known field resistance to SWM using the greenhouse drop-mycelium inoculation method. These 66 PIs were significantly (P < 0.043) different for resistance to SWM. However, year was highly significant (P < 0.00001), while PI x year interaction was not significant (P < 0.623). The second study compared plant mortality (PM) of 35 soybean breeding lines or varieties in greenhouse inoculation methods with disease severity index (DSI) in field evaluations. Moderate correlation (r) between PM under drop-mycelium method and DSI in field trials (r = 0.65, p < 0.0001) was obtained. The PM under spray-mycelium was also correlated significantly with DSI from field trials (r = 0.51, p < 0.0018). Likewise, significant correlation (r = 0.62, p < 0.0001) was obtained between PM across greenhouse inoculation methods and DSI across field trials. These findings suggest that greenhouse inoculation methods could predict the field resistance to SWM. The third study attempted to validate 33 QTL reported in prior studies using seven populations that comprised a total of 392 F4 : 6 lines derived from crosses involving a partially resistant cultivar “Skylla,” five partially resistant PIs, and a known susceptible cultivar “E00290.” The estimates of broad-sense heritability (h2) ranged from 0.39 to 0.66 in the populations. Of the seven populations, four had h2 estimates that were significantly different from zero (p < 0.05). Single marker analysis across populations and inoculation methods identified 11 significant SSRs (p < 0.05) corresponding to 10 QTL identified by prior studies. Thus, these five new PIs could be used as new sources of resistant alleles to develop SWM resistant commercial cultivars. PMID:29731761

Computational studies of an impulsively started viscous flow

NASA Technical Reports Server (NTRS)

Davis, Sanford S.

1988-01-01

Progress in validating incompressible Navier-Stokes codes is described using a predictor/corrector scheme. The flow field under study is the impulsive start of a circular cylinder and the unsteady evolution of the separation bubble. In the current code, a uniform asymptotic expansion is used as an initial condition in order to correctly capture the initial growth of the vortex sheet. Volocity fields at selected instants of time are decomposed into vectorial representations of Navier-Stokes equations which are then used to analyze dominant contributions in the boundary-layer region.

Cognitive Age: A New Multidimensional Approach to Measuring Age Identity.

ERIC Educational Resources Information Center

Barak, Benny

1987-01-01

Conducted exploratory field study to examine how age-concepts are experienced and to assess relationship of age identities to each other. Proposes Cognitive Age as a new multidimensional age scale that merges the standard scale, Identity Age, and Personal Age. Study results attest to Cognitive Age scale's reliability and validity. (Author/NB)

A Study To Evaluate the Effectiveness of the Montana Functional Vision Assessment for Multihandicapped Persons.

ERIC Educational Resources Information Center

Marks, Ron

The study evaluated the validity, reliability, and effectiveness in providing needed information of the Montana Functional Vision Assessment (MFVA) Instrument by comparing it with the Texas Education Agency Functional Vision Assessment and field testing the instrument in evaluations of nine multihandicapped students (ages 3-11). Evaluation led to…

What Motivates Introductory Geology Students to Study for an Exam?

ERIC Educational Resources Information Center

Lukes, Laura A.; McConnell, David A.

2014-01-01

There is a need to understand why some students succeed and persist in STEM fields and others do not. While numerous studies have focused on the positive results of using empirically validated teaching methods in introductory science, technology, engineering, and math (STEM) courses, little data has been collected about the student experience in…

Critical Pedagogy: EFL Teachers' Views, Experience and Academic Degrees

ERIC Educational Resources Information Center

Mahmoodarabi, Mahsa; Khodabakhsh, Mohammad Reza

2015-01-01

Although critical pedagogy has brought about positive changes in the field of education by shifting from traditional pedagogy to emancipatory pedagogy, not much attention has been paid to the factors affecting teachers' beliefs of critical pedagogy and only few studies have been conducted to design reliable and valid instruments to study EFL…

EOS Terra Validation Program

NASA Technical Reports Server (NTRS)

Starr, David

1999-01-01

The EOS Terra mission will be launched in July 1999. This mission has great relevance to the atmospheric radiation community and global change issues. Terra instruments include ASTER, CERES, MISR, MODIS and MOPITT. In addition to the fundamental radiance data sets, numerous global science data products will be generated, including various Earth radiation budget, cloud and aerosol parameters, as well as land surface, terrestrial ecology, ocean color, and atmospheric chemistry parameters. Significant investments have been made in on-board calibration to ensure the quality of the radiance observations. A key component of the Terra mission is the validation of the science data products. This is essential for a mission focused on global change issues and the underlying processes. The Terra algorithms have been subject to extensive pre-launch testing with field data whenever possible. Intensive efforts will be made to validate the Terra data products after launch. These include validation of instrument calibration (vicarious calibration) experiments, instrument and cross-platform comparisons, routine collection of high quality correlative data from ground-based networks, such as AERONET, and intensive sites, such as the SGP ARM site, as well as a variety field experiments, cruises, etc. Airborne simulator instruments have been developed for the field experiment and underflight activities including the MODIS Airborne Simulator (MAS), AirMISR, MASTER (MODIS-ASTER), and MOPITT-A. All are integrated on the NASA ER-2, though low altitude platforms are more typically used for MASTER. MATR is an additional sensor used for MOPITT algorithm development and validation. The intensive validation activities planned for the first year of the Terra mission will be described with emphasis on derived geophysical parameters of most relevance to the atmospheric radiation community. Detailed information about the EOS Terra validation Program can be found on the EOS Validation program homepage i/e.: http://ospso.gsfc.nasa.gov/validation/valpage.html).

A biopsychosocial vignette for case conceptualization in dementia (VIG-Dem): development and pilot study.

PubMed

Spector, Aimee; Hebditch, Molly; Stoner, Charlotte R; Gibbor, Luke

2016-09-01

The ability to identify biological, social, and psychological issues for people with dementia is an important skill for healthcare professionals. Therefore, valid and reliable measures are needed to assess this ability. This study involves the development of a vignette style measure to capture the extent to which health professionals use "Biopsychosocial" thinking in dementia care (VIG-Dem), based on the framework of the model developed by Spector and Orrell (2010). The development process consisted of Phase 1: Developing and refining the vignettes; Phase 2: Field testing (N = 9), and Phase 3: A pilot study to assess reliability and validity (N = 131). The VIG-Dem, consisting of two vignettes with open-ended questions and a standardized scoring scheme, was developed. Evidence for the good inter-rater reliability, convergent validity, and test-retest reliability were established. The VIG-Dem has good psychometric properties and may provide a useful tool in dementia care research and practice.

Percent body fat estimations in college men using field and laboratory methods: a three-compartment model approach.

PubMed

Moon, Jordan R; Tobkin, Sarah E; Smith, Abbie E; Roberts, Michael D; Ryan, Eric D; Dalbo, Vincent J; Lockwood, Chris M; Walter, Ashley A; Cramer, Joel T; Beck, Travis W; Stout, Jeffrey R

2008-04-21

Methods used to estimate percent body fat can be classified as a laboratory or field technique. However, the validity of these methods compared to multiple-compartment models has not been fully established. The purpose of this study was to determine the validity of field and laboratory methods for estimating percent fat (%fat) in healthy college-age men compared to the Siri three-compartment model (3C). Thirty-one Caucasian men (22.5 +/- 2.7 yrs; 175.6 +/- 6.3 cm; 76.4 +/- 10.3 kg) had their %fat estimated by bioelectrical impedance analysis (BIA) using the BodyGram computer program (BIA-AK) and population-specific equation (BIA-Lohman), near-infrared interactance (NIR) (Futrex(R) 6100/XL), four circumference-based military equations [Marine Corps (MC), Navy and Air Force (NAF), Army (A), and Friedl], air-displacement plethysmography (BP), and hydrostatic weighing (HW). All circumference-based military equations (MC = 4.7% fat, NAF = 5.2% fat, A = 4.7% fat, Friedl = 4.7% fat) along with NIR (NIR = 5.1% fat) produced an unacceptable total error (TE). Both laboratory methods produced acceptable TE values (HW = 2.5% fat; BP = 2.7% fat). The BIA-AK, and BIA-Lohman field methods produced acceptable TE values (2.1% fat). A significant difference was observed for the MC and NAF equations compared to both the 3C model and HW (p < 0.006). Results indicate that the BP and HW are valid laboratory methods when compared to the 3C model to estimate %fat in college-age Caucasian men. When the use of a laboratory method is not feasible, BIA-AK, and BIA-Lohman are acceptable field methods to estimate %fat in this population.

Percent body fat estimations in college men using field and laboratory methods: A three-compartment model approach

PubMed Central

Moon, Jordan R; Tobkin, Sarah E; Smith, Abbie E; Roberts, Michael D; Ryan, Eric D; Dalbo, Vincent J; Lockwood, Chris M; Walter, Ashley A; Cramer, Joel T; Beck, Travis W; Stout, Jeffrey R

2008-01-01

Background Methods used to estimate percent body fat can be classified as a laboratory or field technique. However, the validity of these methods compared to multiple-compartment models has not been fully established. The purpose of this study was to determine the validity of field and laboratory methods for estimating percent fat (%fat) in healthy college-age men compared to the Siri three-compartment model (3C). Methods Thirty-one Caucasian men (22.5 ± 2.7 yrs; 175.6 ± 6.3 cm; 76.4 ± 10.3 kg) had their %fat estimated by bioelectrical impedance analysis (BIA) using the BodyGram™ computer program (BIA-AK) and population-specific equation (BIA-Lohman), near-infrared interactance (NIR) (Futrex® 6100/XL), four circumference-based military equations [Marine Corps (MC), Navy and Air Force (NAF), Army (A), and Friedl], air-displacement plethysmography (BP), and hydrostatic weighing (HW). Results All circumference-based military equations (MC = 4.7% fat, NAF = 5.2% fat, A = 4.7% fat, Friedl = 4.7% fat) along with NIR (NIR = 5.1% fat) produced an unacceptable total error (TE). Both laboratory methods produced acceptable TE values (HW = 2.5% fat; BP = 2.7% fat). The BIA-AK, and BIA-Lohman field methods produced acceptable TE values (2.1% fat). A significant difference was observed for the MC and NAF equations compared to both the 3C model and HW (p < 0.006). Conclusion Results indicate that the BP and HW are valid laboratory methods when compared to the 3C model to estimate %fat in college-age Caucasian men. When the use of a laboratory method is not feasible, BIA-AK, and BIA-Lohman are acceptable field methods to estimate %fat in this population. PMID:18426582

Validating spatiotemporal predictions of an important pest of small grains.

PubMed

Merrill, Scott C; Holtzer, Thomas O; Peairs, Frank B; Lester, Philip J

2015-01-01

Arthropod pests are typically managed using tactics applied uniformly to the whole field. Precision pest management applies tactics under the assumption that within-field pest pressure differences exist. This approach allows for more precise and judicious use of scouting resources and management tactics. For example, a portion of a field delineated as attractive to pests may be selected to receive extra monitoring attention. Likely because of the high variability in pest dynamics, little attention has been given to developing precision pest prediction models. Here, multimodel synthesis was used to develop a spatiotemporal model predicting the density of a key pest of wheat, the Russian wheat aphid, Diuraphis noxia (Kurdjumov). Spatially implicit and spatially explicit models were synthesized to generate spatiotemporal pest pressure predictions. Cross-validation and field validation were used to confirm model efficacy. A strong within-field signal depicting aphid density was confirmed with low prediction errors. Results show that the within-field model predictions will provide higher-quality information than would be provided by traditional field scouting. With improvements to the broad-scale model component, the model synthesis approach and resulting tool could improve pest management strategy and provide a template for the development of spatially explicit pest pressure models. © 2014 Society of Chemical Industry.

The Making of a Self-Neglect Severity Scale

NASA Technical Reports Server (NTRS)

Smith, Scott M.; Dyer, C. B.; Pavlik, V. N.; Kelly, P. A.; Lee, J.; Doody, R. S.; Regev, C.; Pickens, C.; Burnett, J.

2006-01-01

Research in elder self-neglect has lagged behind that of other forms of mistreatment, despite the fact that self-neglect is the most common allegation reported to Adult Protective Service agencies throughout the US. The lack of a gold-standard to measure self-neglect has hampered efforts to study this phenomenon. Researchers designed the Self-neglect Severity Scale (SSS) based on interviews with Adult Protective Service workers and a national expert panel. The SSS is based on observation and interview and is administered in the home to include an environmental assessment. It was piloted, extensively field tested and then revised. The CREST SSS was developed using survey data and consultation with experts in the field. This instrument utilizes observer ratings, interview responses, and assesses subjects physical and environmental domains. It also assesses functional status as it relates to health and safety issues. After field and pilot testing the SSS was finalized and is currently undergoing reliability and validity testing. The CREST SSS was developed as a state scale to provide a common language for describing cases of self-neglect. It is the first self-neglect severity scale available to researchers. If found to be both reliable and valid it can be used in future intervention studies.

The making of a self-neglect severity scale.

PubMed

Dyer, Carmel Bitondo; Kelly, P Adam; Pavlik, Valory N; Lee, Jessica; Doody, Rachelle S; Regev, Tziona; Pickens, Sabrina; Burnett, Jason; Smith, Scott M

2006-01-01

Research in elder self-neglect has lagged behind that of other forms of mistreatment, despite the fact that self-neglect is the most common allegation reported to Adult Protective Service agencies throughout the US. The lack of a gold standard to measure self-neglect has hampered efforts to study this phenomenon. Researchers designed the Self-Neglect Severity Scale (SSS) based on interviews with Adult Protective Service workers and a national expert panel. The SSS is based on observation and interview and is administered in the home to include an environmental assessment. It was piloted, extensively field tested and then revised. The CREST SSS was developed using survey data and consultation with experts in the field. This instrument utilizes observer ratings, interview responses, and assesses subjects' physical and environmental domains. It also assesses functional status as it relates to health and safety issues. After field and pilot testing, the SSS was finalized and is currently undergoing reliability and validity testing. The CREST SSS was developed as a state scale to provide a common language for describing cases of self-neglect. It is the first self-neglect severity scale available to researchers. If found to be both reliable and valid, it may be used in future intervention studies.

Calculation of acoustic field based on laser-measured vibration velocities on ultrasonic transducer surface

NASA Astrophysics Data System (ADS)

Hu, Liang; Zhao, Nannan; Gao, Zhijian; Mao, Kai; Chen, Wenyu; Fu, Xin

2018-05-01

Determination of the distribution of a generated acoustic field is valuable for studying ultrasonic transducers, including providing the guidance for transducer design and the basis for analyzing their performance, etc. A method calculating the acoustic field based on laser-measured vibration velocities on the ultrasonic transducer surface is proposed in this paper. Without knowing the inner structure of the transducer, the acoustic field outside it can be calculated by solving the governing partial differential equation (PDE) of the field based on the specified boundary conditions (BCs). In our study, the BC on the transducer surface, i.e. the distribution of the vibration velocity on the surface, is accurately determined by laser scanning measurement of discrete points and follows a data fitting computation. In addition, to ensure the calculation accuracy for the whole field even in an inhomogeneous medium, a finite element method is used to solve the governing PDE based on the mixed BCs, including the discretely measured velocity data and other specified BCs. The method is firstly validated on numerical piezoelectric transducer models. The acoustic pressure distributions generated by a transducer operating in an homogeneous and inhomogeneous medium, respectively, are both calculated by the proposed method and compared with the results from other existing methods. Then, the method is further experimentally validated with two actual ultrasonic transducers used for flow measurement in our lab. The amplitude change of the output voltage signal from the receiver transducer due to changing the relative position of the two transducers is calculated by the proposed method and compared with the experimental data. This method can also provide the basis for complex multi-physical coupling computations where the effect of the acoustic field should be taken into account.

Rice Crop Monitoring Using Microwave and Optical Remotely Sensed Image Data

NASA Astrophysics Data System (ADS)

Suga, Y.; Konishi, T.; Takeuchi, S.; Kitano, Y.; Ito, S.

Hiroshima Institute of Technology HIT is operating the direct down-links of microwave and optical satellite data in Japan This study focuses on the validation for rice crop monitoring using microwave and optical remotely sensed image data acquired by satellites referring to ground truth data such as height of crop ratio of crop vegetation cover and leaf area index in the test sites of Japan ENVISAT-1 ASAR data has a capability to capture regularly and to monitor during the rice growing cycle by alternating cross polarization mode images However ASAR data is influenced by several parameters such as landcover structure direction and alignment of rice crop fields in the test sites In this study the validation was carried out combined with microwave and optical satellite image data and ground truth data regarding rice crop fields to investigate the above parameters Multi-temporal multi-direction descending and ascending and multi-angle ASAR alternating cross polarization mode images were used to investigate rice crop growing cycle LANDSAT data were used to detect landcover structure direction and alignment of rice crop fields corresponding to the backscatter of ASAR As the result of this study it was indicated that rice crop growth can be precisely monitored using multiple remotely sensed data and ground truth data considering with spatial spectral temporal and radiometric resolutions

Calibration and validation of wearable monitors.

PubMed

Bassett, David R; Rowlands, Alex; Trost, Stewart G

2012-01-01

Wearable monitors are increasingly being used to objectively monitor physical activity in research studies within the field of exercise science. Calibration and validation of these devices are vital to obtaining accurate data. This article is aimed primarily at the physical activity measurement specialist, although the end user who is conducting studies with these devices also may benefit from knowing about this topic. Initially, wearable physical activity monitors should undergo unit calibration to ensure interinstrument reliability. The next step is to simultaneously collect both raw signal data (e.g., acceleration) from the wearable monitors and rates of energy expenditure, so that algorithms can be developed to convert the direct signals into energy expenditure. This process should use multiple wearable monitors and a large and diverse subject group and should include a wide range of physical activities commonly performed in daily life (from sedentary to vigorous). New methods of calibration now use "pattern recognition" approaches to train the algorithms on various activities, and they provide estimates of energy expenditure that are much better than those previously available with the single-regression approach. Once a method of predicting energy expenditure has been established, the next step is to examine its predictive accuracy by cross-validating it in other populations. In this article, we attempt to summarize the best practices for calibration and validation of wearable physical activity monitors. Finally, we conclude with some ideas for future research ideas that will move the field of physical activity measurement forward.

Development and validation of a survey instrument for assessing prescribers' perception of computerized drug-drug interaction alerts.

PubMed

Zheng, Kai; Fear, Kathleen; Chaffee, Bruce W; Zimmerman, Christopher R; Karls, Edward M; Gatwood, Justin D; Stevenson, James G; Pearlman, Mark D

2011-12-01

To develop a theoretically informed and empirically validated survey instrument for assessing prescribers' perception of computerized drug-drug interaction (DDI) alerts. The survey is grounded in the unified theory of acceptance and use of technology and an adapted accident causation model. Development of the instrument was also informed by a review of the extant literature on prescribers' attitude toward computerized medication safety alerts and common prescriber-provided reasons for overriding. To refine and validate the survey, we conducted a two-stage empirical validation study consisting of a pretest with a panel of domain experts followed by a field test among all eligible prescribers at our institution. The resulting survey instrument contains 28 questionnaire items assessing six theoretical dimensions: performance expectancy, effort expectancy, social influence, facilitating conditions, perceived fatigue, and perceived use behavior. Satisfactory results were obtained from the field validation; however, a few potential issues were also identified. We analyzed these issues accordingly and the results led to the final survey instrument as well as usage recommendations. High override rates of computerized medication safety alerts have been a prevalent problem. They are usually caused by, or manifested in, issues of poor end user acceptance. However, standardized research tools for assessing and understanding end users' perception are currently lacking, which inhibits knowledge accumulation and consequently forgoes improvement opportunities. The survey instrument presented in this paper may help fill this methodological gap. We developed and empirically validated a survey instrument that may be useful for future research on DDI alerts and other types of computerized medication safety alerts more generally.

Robustness and Uncertainty: Applications for Policy in Climate and Hydrological Modeling

NASA Astrophysics Data System (ADS)

Fields, A. L., III

2015-12-01

Policymakers must often decide how to proceed when presented with conflicting simulation data from hydrological, climatological, and geological models. While laboratory sciences often appeal to the reproducibility of results to argue for the validity of their conclusions, simulations cannot use this strategy for a number of pragmatic and methodological reasons. However, robustness of predictions and causal structures can serve the same function for simulations as reproducibility does for laboratory experiments and field observations in either adjudicating between conflicting results or showing that there is insufficient justification to externally validate the results. Additionally, an interpretation of the argument from robustness is presented that involves appealing to the convergence of many well-built and diverse models rather than the more common version which involves appealing to the probability that one of a set of models is likely to be true. This interpretation strengthens the case for taking robustness as an additional requirement for the validation of simulation results and ultimately supports the idea that computer simulations can provide information about the world that is just as trustworthy as data from more traditional laboratory studies and field observations. Understanding the importance of robust results for the validation of simulation data is especially important for policymakers making decisions on the basis of potentially conflicting models. Applications will span climate, hydrological, and hydroclimatological models.

Forensic analysis of explosives using isotope ratio mass spectrometry (IRMS)--part 1: instrument validation of the DELTAplusXP IRMS for bulk nitrogen isotope ratio measurements.

PubMed

Benson, Sarah J; Lennard, Christopher J; Hill, David M; Maynard, Philip; Roux, Claude

2010-01-01

A significant amount of research has been conducted into the use of stable isotopes to assist in determining the origin of various materials. The research conducted in the forensic field shows the potential of isotope ratio mass spectrometry (IRMS) to provide a level of discrimination not achievable utilizing traditional forensic techniques. Despite the research there have been few, if any, publications addressing the validation and measurement uncertainty of the technique for forensic applications. This study, the first in a planned series, presents validation data for the measurement of bulk nitrogen isotope ratios in ammonium nitrate (AN) using the DELTA(plus)XP (Thermo Finnigan) IRMS instrument equipped with a ConFlo III interface and FlashEA 1112 elemental analyzer (EA). Appropriate laboratory standards, analytical methods and correction calculations were developed and evaluated. A validation protocol was developed in line with the guidelines provided by the National Association of Testing Authorities, Australia (NATA). Performance characteristics including: accuracy, precision/repeatability, reproducibility/ruggedness, robustness, linear range, and measurement uncertainty were evaluated for the measurement of nitrogen isotope ratios in AN. AN (99.5%) and ammonium thiocyanate (99.99+%) were determined to be the most suitable laboratory standards and were calibrated against international standards (certified reference materials). All performance characteristics were within an acceptable range when potential uncertainties, including the manufacturer's uncertainty of the technique and standards, were taken into account. The experiments described in this article could be used as a model for validation of other instruments for similar purposes. Later studies in this series will address the more general issue of demonstrating that the IRMS technique is scientifically sound and fit-for-purpose in the forensic explosives analysis field.

Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study.

PubMed

Vogel, Michael W; Giorni, Andrea; Vegh, Viktor; Pellicer-Guridi, Ruben; Reutens, David C

2016-01-01

We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20-50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably.

Measurement of EMG activity with textile electrodes embedded into clothing.

PubMed

Finni, T; Hu, M; Kettunen, P; Vilavuo, T; Cheng, S

2007-11-01

Novel textile electrodes that can be embedded into sports clothing to measure averaged rectified electromyography (EMG) have been developed for easy use in field tests and in clinical settings. The purpose of this study was to evaluate the validity, reliability and feasibility of this new product to measure averaged rectified EMG. The validity was tested by comparing the signals from bipolar textile electrodes (42 cm(2)) and traditional bipolar surface electrodes (1.32 cm(2)) during bilateral isometric knee extension exercise with two electrode locations (A: both electrodes located in the same place, B: traditional electrodes placed on the individual muscles according to SENIAM, n=10 persons for each). Within-session repeatability (the coefficient of variation CV%, n=10) was calculated from five repetitions of 60% maximum voluntary contraction (MVC). The day-to-day repeatability (n=8) was assessed by measuring three different isometric force levels on five consecutive days. The feasibility of the textile electrodes in field conditions was assessed during a maximal treadmill test (n=28). Bland-Altman plots showed a good agreement within 2SD between the textile and traditional electrodes, demonstrating that the textile electrodes provide similar information on the EMG signal amplitude to the traditional electrodes. The within-session CV ranged from 13% to 21% in both the textile and traditional electrodes. The day-to-day CV was smaller, ranging from 4% to 11% for the textile electrodes. A similar relationship (r(2)=0.5) was found between muscle strength and the EMG of traditional and textile electrodes. The feasibility study showed that the textile electrode technique can potentially make EMG measurements very easy in field conditions. This study indicates that textile electrodes embedded into shorts is a valid and feasible method for assessing the average rectified value of EMG.

Precise SAR measurements in the near-field of RF antenna systems

NASA Astrophysics Data System (ADS)

Hakim, Bandar M.

Wireless devices must meet specific safety radiation limits, and in order to assess the health affects of such devices, standard procedures are used in which standard phantoms, tissue-equivalent liquids, and miniature electric field probes are used. The accuracy of such measurements depend on the precision in measuring the dielectric properties of the tissue-equivalent liquids and the associated calibrations of the electric-field probes. This thesis describes work on the theoretical modeling and experimental measurement of the complex permittivity of tissue-equivalent liquids, and associated calibration of miniature electric-field probes. The measurement method is based on measurements of the field attenuation factor and power reflection coefficient of a tissue-equivalent sample. A novel method, to the best of the authors knowledge, for determining the dielectric properties and probe calibration factors is described and validated. The measurement system is validated using saline at different concentrations, and measurements of complex permittivity and calibration factors have been made on tissue-equivalent liquids at 900MHz and 1800MHz. Uncertainty analysis have been conducted to study the measurement system sensitivity. Using the same waveguide to measure tissue-equivalent permittivity and calibrate e-field probes eliminates a source of uncertainty associated with using two different measurement systems. The measurement system is used to test GSM cell-phones at 900MHz and 1800MHz for Specific Absorption Rate (SAR) compliance using a Specific Anthropomorphic Mannequin phantom (SAM).

Analysis of eddy currents induced by transverse and longitudinal gradient coils in different tungsten collimators geometries for SPECT/MRI integration.

PubMed

Samoudi, Amine M; Van Audenhaege, Karen; Vermeeren, Günter; Poole, Michael; Tanghe, Emmeric; Martens, Luc; Van Holen, Roel; Joseph, Wout

2015-12-01

We investigated the temporal variation of the induced magnetic field due to the transverse and the longitudinal gradient coils in tungsten collimators arranged in hexagonal and pentagonal geometries with and without gaps between the collimators. We modeled x-, y-, and z-gradient coils and different arrangements of single-photon emission computed tomography (SPECT) collimators using FEKO, a three-dimensional electromagnetic simulation tool. A time analysis approach was used to generate the pulsed magnetic field gradient. The approach was validated with measurements using a 7T MRI scanner. Simulations showed an induced magnetic field representing 4.66% and 0.87% of the applied gradient field (gradient strength = 500 mT/m) for longitudinal and transverse gradient coils, respectively. These values can be reduced by 75% by adding gaps between the collimators for the pentagonal arrangement, bringing the maximum induced magnetic field to less than 2% of the applied gradient for all of the gradient coils. Characterization of the maximum induced magnetic field shows that by adding gaps between the collimators for an integrated SPECT/MRI system, eddy currents can be corrected by the MRI system to avoid artifact. The numerical model was validated and was proposed as a tool for studying the effect of a SPECT collimator within the MRI gradient coils. © 2014 Wiley Periodicals, Inc.

Supporting the Use of GPM-GV Field Campaign Data Beyond Project Scientists

NASA Astrophysics Data System (ADS)

Weigel, A. M.; Smith, D. K.; Sinclair, L.; Bugbee, K.

2017-12-01

The Global Precipitation Measurement (GPM) Mission Ground Validation (GV) consisted of a collection of field campaigns at various locations focusing on particular aspects of precipitation. Data collected during the GPM-GV are necessary for better understanding the instruments and algorithms used to monitor water resources, study the global hydrologic cycle, understand climate variability, and improve weather prediction. The GPM-GV field campaign data have been archived at the NASA Global Hydrology Resource Center (GHRC) Distributed Achive Archive Center (DAAC). These data consist of a heterogeneous collection of observations that require careful handling, full descriptive user guides, and helpful instructions for data use. These actions are part of the data archival process. In addition, the GHRC focuses on expanding the use of GPM-GV data beyond the validation and instrument researchers that participated in the field campaigns. To accomplish this, GHRC ties together the similarities and differences between the various field campaigns with the goal of improving user documents to be more easily read by those outside the field of research. In this poster, the authors will describe the GPM-GV datasets, discuss data use among the broader community, outline the types of problems/issues with these datasets, demonstrate what tools support data visualization and use, and highlight the outreach materials developed to educate both younger and general audiences about the data.

Scientific Inquiry Competency Perception Scale (The Case of Kazak Post-Graduate Students) Reliability and Validity Study

ERIC Educational Resources Information Center

Gelisli, Yücel; Beisenbayeva, Lyazzat

2017-01-01

The purpose of the current study is to develop a reliable scale to be used to determine the scientific inquiry competency perception of post-graduate students engaged in post-graduate studies in the field of educational sciences and teacher education in Kazakhstan. The study employed the descriptive method. Within the context of the study, a scale…

Using the WSA Model to Test the Parker Spiral Approximation for SEP Event Magnetic Connections

NASA Astrophysics Data System (ADS)

Kahler, S. W.; Arge, C. N.; Smith, D. A.

2016-08-01

In studies of solar energetic (E > 10 MeV) particle (SEP) events the Parker spiral (PS) field approximation, based only on the measured 1 AU solar wind (SW) speed Vsw, is nearly always used to determine the coronal or photospheric source locations of the 1 AU magnetic fields. There is no objective way to validate that approximation, but here we seek guidelines for optimizing its application. We first review recent SEP studies showing the extensive use of the PS approximation with various assumptions about coronal and photospheric source fields. We then run the Wang-Sheeley-Arge (WSA) model over selected Carrington rotations (CRs) to track both the photospheric and 5 R_{⊙} source locations of the forecasted 1 AU SW, allowing us to compare those WSA sources with the PS sources inferred from the WSA Vsw forecast. We compile statistics of the longitude differences (WSA-PS) for all the CRs and discuss the limitations of using the WSA model to validate the PS approximation. Over nearly all of each CR the PS and WSA source longitudes agree to within several degrees. The agreement is poor only in the slow-fast SW interaction regions characterized by high-speed events (HSEs), where the longitude differences can reach several tens of degrees. This result implies that SEP studies should limit use of the PS approximation around HSEs and use magnetic field polarities as an additional check of solar source connections.

Validation of Finite-Element Models of Persistent-Current Effects in Nb 3Sn Accelerator Magnets

DOE PAGES

Wang, X.; Ambrosio, G.; Chlachidze, G.; ...

2015-01-06

Persistent magnetization currents are induced in superconducting filaments during the current ramping in magnets. The resulting perturbation to the design magnetic field leads to field quality degradation, in particular at low field where the effect is stronger relative to the main field. The effects observed in NbTi accelerator magnets were reproduced well with the critical-state model. However, this approach becomes less accurate for the calculation of the persistent-current effects observed in Nb 3Sn accelerator magnets. Here a finite-element method based on the measured strand magnetization is validated against three state-of-art Nb3Sn accelerator magnets featuring different subelement diameters, critical currents, magnetmore » designs and measurement temperatures. The temperature dependence of the persistent-current effects is reproduced. Based on the validated model, the impact of conductor design on the persistent current effects is discussed. The performance, limitations and possible improvements of the approach are also discussed.« less

Influence of the Aral Sea negative water balance on its seasonal circulation and ventilation patterns: use of a 3d hydrodynamic model.

NASA Astrophysics Data System (ADS)

Sirjacobs, D.; Grégoire, M.; Delhez, E.; Nihoul, J.

2003-04-01

Within the context of the EU INCO-COPERNICUS program "Desertification in the Aral Sea Region: A study of the Natural and Anthropogenic Impacts" (Contract IAC2-CT-2000-10023), a large-scale 3D hydrodynamic model was adapted to address specifically the macroscale processes affecting the Aral Sea water circulation and ventilation. The particular goal of this research is to simulate the effect of lasting negative water balance on the 3D seasonal circulation, temperature, salinity and water-mixing fields of the Aral Sea. The original Aral Sea seasonal hydrodynamism is simulated with the average seasonal forcings corresponding to the period from 1956 to 1960. This first investigation concerns a period of relative stability of the water balance, before the beginning of the drying process. The consequences of the drying process on the hydrodynamic of the Sea will be studied by comparing this first results with the simulation representing the average situation for the years 1981 to 1985, a very low river flow period. For both simulation periods, the forcing considered are the seasonal fluctuations of wind fields, precipitation, evaporation, river discharge and salinity, cloud cover, air temperature and humidity. The meteorological forcings were adapted to the common optimum one-month temporal resolution of the available data sets. Monthly mean kinetic energy flux and surface tensions were calculated from daily ECMWF wind data. Monthly in situ precipitation, surface air temperature and humidity fields were interpolated from data obtained from the Russian Hydrological and Meteorological Institute. Monthly water discharge and average salinity of the river water were considered for both Amu Darya and Syr Darya river over each simulation periods. The water mass conservation routines allowed the simulation of a changing coastline by taking into account local drying and flooding events of particular grid points. Preliminary barotropic runs were realised (for the 1951-1960 situation, before drying up began) in order to get a first experience of the behaviour of the hydrodynamic model. These first runs provide results about the evolution of the following state variables: elevation of the sea surface, 3D fields of vertical and horizontal flows, 2D fields of average horizontal flows and finally the 3D fields of turbulent kinetic energy. The mean seasonal salinity and temperature fields (in-situ data gathered by the Russian Hydrological and Meteorological Institute) are available for the two simulated periods and will allow a first validation of the hydrodynamic model. Various satellites products were identified, collected and processed in the frame of this research project and will be used for the validation of the model outputs. Seasonal level changes measurements derived from water table change will serve for water balance validation and sea surface temperature for hydrodynamics validation.

Calibration and validation of rockfall models

NASA Astrophysics Data System (ADS)

Frattini, Paolo; Valagussa, Andrea; Zenoni, Stefania; Crosta, Giovanni B.

2013-04-01

Calibrating and validating landslide models is extremely difficult due to the particular characteristic of landslides: limited recurrence in time, relatively low frequency of the events, short durability of post-event traces, poor availability of continuous monitoring data, especially for small landslide and rockfalls. For this reason, most of the rockfall models presented in literature completely lack calibration and validation of the results. In this contribution, we explore different strategies for rockfall model calibration and validation starting from both an historical event and a full-scale field test. The event occurred in 2012 in Courmayeur (Western Alps, Italy), and caused serious damages to quarrying facilities. This event has been studied soon after the occurrence through a field campaign aimed at mapping the blocks arrested along the slope, the shape and location of the detachment area, and the traces of scars associated to impacts of blocks on the slope. The full-scale field test was performed by Geovert Ltd in the Christchurch area (New Zealand) after the 2011 earthquake. During the test, a number of large blocks have been mobilized from the upper part of the slope and filmed with high velocity cameras from different viewpoints. The movies of each released block were analysed to identify the block shape, the propagation path, the location of impacts, the height of the trajectory and the velocity of the block along the path. Both calibration and validation of rockfall models should be based on the optimization of the agreement between the actual trajectories or location of arrested blocks and the simulated ones. A measure that describe this agreement is therefore needed. For calibration purpose, this measure should simple enough to allow trial and error repetitions of the model for parameter optimization. In this contribution we explore different calibration/validation measures: (1) the percentage of simulated blocks arresting within a buffer of the actual blocks, (2) the percentage of trajectories passing through the buffer of the actual rockfall path, (3) the mean distance between the location of arrest of each simulated blocks and the location of the nearest actual blocks; (4) the mean distance between the location of detachment of each simulated block and the location of detachment of the actual block located closer to the arrest position. By applying the four measures to the case studies, we observed that all measures are able to represent the model performance for validation purposes. However, the third measure is more simple and reliable than the others, and seems to be optimal for model calibration, especially when using a parameter estimation and optimization modelling software for automated calibration.

Validation of the GOES-16 magnetometer using multipoint measurements and magnetic field models

NASA Astrophysics Data System (ADS)

Califf, S.; Loto'aniu, P. T. M.; Redmon, R. J.; Sarris, T. E.; Brito, T.

2017-12-01

The Geostationary Operational Environmental Satellites (GOES) have been providing continuous geomagnetic field measurements for over 40 years. While the primary purpose of GOES is operational, the magnetometer data are also widely used in the scientific community. In an effort to validate the recently launched GOES-16 magnetometer, we compare the measurements to existing magnetic field models and other GOES spacecraft currently on orbit. There are four concurrent measurements from GOES-13, 14, 15 and 16 spanning 75W to 135W longitude. Also, GOES-13 is being replaced by GOES-16 in the GOES-East location, and during the transition, GOES-13 and GOES-16 will be parked nearby in order to assist with calibration of the new operational satellite. This work explores techniques to quantify the performance of the GOES-16 magnetometer by comparison to data from nearby spacecraft. We also build on previous work to assimilate in situ measurements with existing magnetic field models to assist in comparing data from different spatial locations. Finally, we use this unique dataset from four simultaneous geosynchronous magnetometer measurements and the close separation between GOES-13 and GOES-16 to study the spatial characteristics of ULF waves and other magnetospheric processes.

Predicting field-scale dispersion under realistic conditions with the polar Markovian velocity process model

NASA Astrophysics Data System (ADS)

Dünser, Simon; Meyer, Daniel W.

2016-06-01

In most groundwater aquifers, dispersion of tracers is dominated by flow-field inhomogeneities resulting from the underlying heterogeneous conductivity or transmissivity field. This effect is referred to as macrodispersion. Since in practice, besides a few point measurements the complete conductivity field is virtually never available, a probabilistic treatment is needed. To quantify the uncertainty in tracer concentrations from a given geostatistical model for the conductivity, Monte Carlo (MC) simulation is typically used. To avoid the excessive computational costs of MC, the polar Markovian velocity process (PMVP) model was recently introduced delivering predictions at about three orders of magnitude smaller computing times. In artificial test cases, the PMVP model has provided good results in comparison with MC. In this study, we further validate the model in a more challenging and realistic setup. The setup considered is derived from the well-known benchmark macrodispersion experiment (MADE), which is highly heterogeneous and non-stationary with a large number of unevenly scattered conductivity measurements. Validations were done against reference MC and good overall agreement was found. Moreover, simulations of a simplified setup with a single measurement were conducted in order to reassess the model's most fundamental assumptions and to provide guidance for model improvements.

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

Quinn, Heather; Wirthlin, Michael

A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA inmore » a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this study we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.« less

OVERFLOW Validation for Predicting Plume Impingement of Underexpanded Axisymmetric Jets onto Angled Flat Plates

NASA Technical Reports Server (NTRS)

Lee, Henry C.; Klopfer, Goetz

2011-01-01

This report documents how OVERFLOW, a computational fluid dynamics code, predicts plume impingement of underexpanded axisymmetric jets onto both perpendicular and inclined flat plates. The effects of the plume impinging on a range of plate inclinations varying from 90deg to 30deg are investigated and compared to the experimental results in Reference 1 and 2. The flow fields are extremely complex due to the interaction between the shock waves from the free jet and those deflected by the plate. Additionally, complex mixing effects create very intricate structures in the flow. The experimental data is very limited, so these validation studies will focus only on cold plume impingement on flat and inclined plates. This validation study will help quantify the error in the OVERFLOW simulation when applied to stage separation scenarios.

Promoting and inhibiting factors for the use of validated dietary assessment questionnaires in health check-up counseling: from occupational health nurses and dietitians' perspective.

PubMed

Katagiri, Ryoko; Muto, Go; Sasaki, Satoshi

2018-06-01

A validated questionnaire is not typically used for dietary assessment in health check-up counseling provided by occupational health nurses in Japan. We conducted a qualitative study to investigate the barriers and promoting factors affecting the use of validated questionnaires. Ten occupational health nurses and three registered dietitians, working at a health insurance society, were recruited for this study using an open-ended, free description questionnaire. Inhibiting factors, such as "Feeling of satisfaction with the current method," "Recognition of importance," and "Sense of burden from the questionnaire", and as promoting factors, "Feeling the current method is insufficient", "Recognition of importance," "Reduction in the feeling of burden after the answer," "Expectation of and reaction to the result," and "Expectation for the effect of the counseling" were noted. Since a standardized dietary assessment method in health counseling might be desirable for the harmonization of work with diseases prevention in an occupational field, findings in this study could propose appropriate targets to reduce confusion in health professionals' concerning the use of validated questionnaires.

R1 dispersion contrast at high field with fast field-cycling MRI

NASA Astrophysics Data System (ADS)

Bödenler, Markus; Basini, Martina; Casula, Maria Francesca; Umut, Evrim; Gösweiner, Christian; Petrovic, Andreas; Kruk, Danuta; Scharfetter, Hermann

2018-05-01

Contrast agents with a strong R1 dispersion have been shown to be effective in generating target-specific contrast in MRI. The utilization of this R1 field dependence requires the adaptation of an MRI scanner for fast field-cycling (FFC). Here, we present the first implementation and validation of FFC-MRI at a clinical field strength of 3 T. A field-cycling range of ±100 mT around the nominal B0 field was realized by inserting an additional insert coil into an otherwise conventional MRI system. System validation was successfully performed with selected iron oxide magnetic nanoparticles and comparison to FFC-NMR relaxometry measurements. Furthermore, we show proof-of-principle R1 dispersion imaging and demonstrate the capability of generating R1 dispersion contrast at high field with suppressed background signal. With the presented ready-to-use hardware setup it is possible to investigate MRI contrast agents with a strong R1 dispersion at a field strength of 3 T.

GIS-aided Statistical Landslide Susceptibility Modeling And Mapping Of Antipolo Rizal (Philippines)

NASA Astrophysics Data System (ADS)

Dumlao, A. J.; Victor, J. A.

2015-09-01

Slope instability associated with heavy rainfall or earthquake is a familiar geotechnical problem in the Philippines. The main objective of this study is to perform a detailed landslide susceptibility assessment of Antipolo City. The statistical method of assessment used was logistic regression. Landslide inventory was done through interpretation of aerial photographs and satellite images with corresponding field verification. In this study, morphologic and non-morphologic factors contributing to landslide occurrence and their corresponding spatial relationships were considered. The analysis of landslide susceptibility was implemented in a Geographic Information System (GIS). The 17320 randomly selected datasets were divided into training and test data sets. K- cross fold validation is done with k= 5. The subsamples are then fitted five times with k-1 training data set and the remaining fold as the validation data set. The AUROC of each model is validated using each corresponding data set. The AUROC of the five models are; 0.978, 0.977, 0.977, 0.974, and 0.979 respectively, implying that the models are effective in correctly predicting the occurrence and nonoccurrence of landslide activity. Field verification was also done. The landslide susceptibility map was then generated from the model. It is classified into four categories; low, moderate, high and very high susceptibility. The study also shows that almost 40% of Antipolo City has been assessed to be potentially dangerous areas in terms of landslide occurrence.

Neutral meson properties under an external magnetic field in nonlocal chiral quark models

NASA Astrophysics Data System (ADS)

Gómez Dumm, D.; Izzo Villafañe, M. F.; Scoccola, N. N.

2018-02-01

We study the behavior of neutral meson properties in the presence of a static uniform external magnetic field in the context of nonlocal chiral quark models. The formalism is worked out introducing Ritus transforms of Dirac fields, which allow to obtain closed analytical expressions for π0 and σ meson masses and for the π0 decay constant. Numerical results for these observables are quoted for various parametrizations. In particular, the behavior of the π0 meson mass with the magnetic field is found to be in good agreement with lattice QCD results. It is also seen that the Goldberger-Treiman and Gell-Mann-Oakes-Renner chiral relations remain valid within these models in the presence of the external magnetic field.

Estimating the Geoelectric Field Using Precomputed EMTFs: Effect of Magnetometer Cadence

NASA Astrophysics Data System (ADS)

Grawe, M.; Butala, M.; Makela, J. J.; Kamalabadi, F.

2017-12-01

Studies that make use of electromagnetic transfer functions (EMTFs) to calculate the surface electric field from a specified surface magnetic field often use historical magnetometer information for validation and comparison purposes. Depending on the data source, the magnetometer cadence is typically between 1 and 60 seconds. It is often implied that a 60 (and sometimes 10) second cadence is acceptable for purposes of geoelectric field calculation using a geophysical model. Here, we quantitatively assess this claim under different geological settings and using models of varying complexity (using uniform/1D/3D EMTFs) across several different space weather events. Conclusions are made about sampling rate sufficiency as a function of local geology and the spectral content of the surface magnetic field.

The Preferred Learning Styles of Neurosurgeons, Neurosurgery Residents, and Neurology Residents: Implications in the Neurosurgical Field.

PubMed

Lai, Hung-Yi; Lee, Ching-Yi; Chiu, Angela; Lee, Shih-Tseng

2014-01-01

To delineate the learning style that best defines a successful practitioner in the field of neurosurgery by using a validated learning style inventory. The Kolb Learning Style Inventory, a validated assessment tool, was administered to all practicing neurosurgeons, neurosurgical residents, and neurology residents employed at Chang Gung Memorial Hospital, an institution that provides primary and tertiary clinical care in 3 locations, Linkou, Kaohsiung, and Chiayi. There were 81 participants who entered the study, and all completed the study. Neurosurgeons preferred the assimilating learning style (52%), followed by the diverging learning style (39%). Neurosurgery residents were slightly more evenly distributed across the learning styles; however, they still favored assimilating (32%) and diverging (41%). Neurology residents had the most clearly defined preferred learning style with assimilating (76%) obtaining the large majority and diverging (12%) being a distant second. The assimilating and diverging learning styles are the preferred learning styles among neurosurgeons, neurosurgery residents, and neurology residents. The assimilating learning style typically is the primary learning style for neurosurgeons and neurology residents. Neurosurgical residents start off with a diverging learning style and progress toward an assimilating learning style as they work toward becoming practicing neurosurgeons. The field of neurosurgery has limited opportunities for active experimentation, which may explain why individuals who prefer reflective observation are more likely to succeed in this field. Copyright © 2014 Elsevier Inc. All rights reserved.

Roles of Naturalistic Observation in Comparative Psychology

ERIC Educational Resources Information Center

Miller, David B.

1977-01-01

"Five roles are considered by which systematic, quantified field research can augment controlled laboratory experimentation in terms of increasing the validity of laboratory studies." Advocates that comparative psychologists should "take more initiative in designing, executing, and interpreting our experiments with regard to the natural history of…

76 FR 4096 - Notice of Submission for OMB Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-24

..., including the validity of the methodology and assumptions used; (3) Enhance the quality, utility, and...: Revision. Title of Collection: 2011-12 National Postsecondary Student Aid Study (NPSAS:12) Field Test...: Annually. Affected Public: Individuals or households; Businesses or other for-profit; Not-for-profit...

ESTABLISHMENT OF A GROUNDWATER RESEARCH DATA CENTER FOR VALIDATION OF SUBSURFACE FLOW AND TRANSPORT MODELS

EPA Science Inventory

The International Ground Water Modeling Center has established a Groundwater Research Data Center that provides information on datasets resulting from publicly funded field experiments and related bench studies in soil and groundwater pollution and distributes datasets for tes...

THE ESTABLISHMENT OF A GROUNDWATER RESEARCH DATA CENTER FOR VALIDATION OF SUBSURFACE FLOW AND TRANSPORT MODELS

EPA Science Inventory

The International Ground Water Modeling Center has established a Groundwater Research Data Center which provides information on research datasets resulting from publicly funded field experiments regarding soil and groundwater pollution and related laboratory bench studies, and wh...

Validation of Two Portable Instruments to Measure Iron Concentration in Groundwater in Rural Bangladesh

PubMed Central

Merrill, Rebecca D.; Shamim, Abu Ahmed; Ali, Hasmot; Schulze, Kerry; Rashid, Mahbubur; Christian, Parul; West, Jr., Keith P.

2009-01-01

Iron is ubiquitous in natural water sources used around the world for drinking and cooking. The health impact of chronic exposure to iron through water, which in groundwater sources can reach well above the World Health Organization's defined aesthetic limit of 0.3 mg/L, is not currently understood. To quantify the impact of consumption of iron in groundwater on nutritional status, it is important to accurately assess naturally-occurring exposure levels among populations. In this study, the validity of iron quantification in water was evaluated using two portable instruments: the HACH DR/890 portable colorimeter (colorimeter) and HACH Iron test-kit, Model IR-18B (test-kit), by comparing field-based iron estimates for 25 tubewells located in northwestern Bangladesh with gold standard atomic absorption spectrophotometry analysis. Results of the study suggest that the HACH test-kit delivers more accurate point-of-use results across a wide range of iron concentrations under challenging field conditions. PMID:19507757

Accuracy of genomic selection in European maize elite breeding populations.

PubMed

Zhao, Yusheng; Gowda, Manje; Liu, Wenxin; Würschum, Tobias; Maurer, Hans P; Longin, Friedrich H; Ranc, Nicolas; Reif, Jochen C

2012-03-01

Genomic selection is a promising breeding strategy for rapid improvement of complex traits. The objective of our study was to investigate the prediction accuracy of genomic breeding values through cross validation. The study was based on experimental data of six segregating populations from a half-diallel mating design with 788 testcross progenies from an elite maize breeding program. The plants were intensively phenotyped in multi-location field trials and fingerprinted with 960 SNP markers. We used random regression best linear unbiased prediction in combination with fivefold cross validation. The prediction accuracy across populations was higher for grain moisture (0.90) than for grain yield (0.58). The accuracy of genomic selection realized for grain yield corresponds to the precision of phenotyping at unreplicated field trials in 3-4 locations. As for maize up to three generations are feasible per year, selection gain per unit time is high and, consequently, genomic selection holds great promise for maize breeding programs.

Validation of two portable instruments to measure iron concentration in groundwater in rural Bangladesh.

PubMed

Merrill, Rebecca D; Shamim, Abu Ahmed; Labrique, Alain B; Ali, Hasmot; Schulze, Kerry; Rashid, Mahbubur; Christian, Parul; West, Keith P

2009-06-01

Iron is ubiquitous in natural water sources used around the world for drinking and cooking. The health impact of chronic exposure to iron through water, which in groundwater sources can reach well above the World Health Organization's defined aesthetic limit of 0.3 mg/L, is not currently understood. To quantify the impact of consumption of iron in groundwater on nutritional status, it is important to accurately assess naturally-occurring exposure levels among populations. In this study, the validity of iron quantification in water was evaluated using two portable instruments: the HACH DR/890 portable colorimeter (colorimeter) and HACH Iron test-kit, Model IR-18B (test-kit), by comparing field-based iron estimates for 25 tubewells located in northwestern Bangladesh with gold standard atomic absorption spectrophotometry analysis. Results of the study suggest that the HACH test-kit delivers more accurate point-of-use results across a wide range of iron concentrations under challenging field conditions.

Validation of IRDFF in 252Cf standard and IRDF-2002 reference neutron fields

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

Simakov, Stanislav; Capote Noy, Roberto; Greenwood, Lawrence R.

The results of validation of the latest release of International Reactor Dosimetry and Fusion File, IRDFF-1.03, in the standard 252Cf(s.f.) and reference 235U(nth,f) neutron benchmark fields are presented. The spectrum-averaged cross sections were shown to confirm the recommended spectrum for 252Cf spontaneous fission source; that was not the case for the current recommended spectra for 235U(nth,f). IRDFF was also validated in the spectra of the research reactor facilities ISNF, Sigma-Sigma and YAYOI, which are available in the IRDF- 2002 collection. Before this analysis, the ISFN spectrum was resimulated to remove unphysical oscillations in spectrum. IRDFF-1.03 was shown to reasonably reproducemore » the spectrum-averaged data measured in these fields except for the case of YAYOI.« less

Implementation and application of an interactive user-friendly validation software for RADIANCE

NASA Astrophysics Data System (ADS)

Sundaram, Anand; Boonn, William W.; Kim, Woojin; Cook, Tessa S.

2012-02-01

RADIANCE extracts CT dose parameters from dose sheets using optical character recognition and stores the data in a relational database. To facilitate validation of RADIANCE's performance, a simple user interface was initially implemented and about 300 records were evaluated. Here, we extend this interface to achieve a wider variety of functions and perform a larger-scale validation. The validator uses some data from the RADIANCE database to prepopulate quality-testing fields, such as correspondence between calculated and reported total dose-length product. The interface also displays relevant parameters from the DICOM headers. A total of 5,098 dose sheets were used to test the performance accuracy of RADIANCE in dose data extraction. Several search criteria were implemented. All records were searchable by accession number, study date, or dose parameters beyond chosen thresholds. Validated records were searchable according to additional criteria from validation inputs. An error rate of 0.303% was demonstrated in the validation. Dose monitoring is increasingly important and RADIANCE provides an open-source solution with a high level of accuracy. The RADIANCE validator has been updated to enable users to test the integrity of their installation and verify that their dose monitoring is accurate and effective.

Issues in cross-cultural validity: example from the adaptation, reliability, and validity testing of a Turkish version of the Stanford Health Assessment Questionnaire.

PubMed

Küçükdeveci, Ayse A; Sahin, Hülya; Ataman, Sebnem; Griffiths, Bridget; Tennant, Alan

2004-02-15

Guidelines have been established for cross-cultural adaptation of outcome measures. However, invariance across cultures must also be demonstrated through analysis of Differential Item Functioning (DIF). This is tested in the context of a Turkish adaptation of the Health Assessment Questionnaire (HAQ). Internal construct validity of the adapted HAQ is assessed by Rasch analysis; reliability, by internal consistency and the intraclass correlation coefficient; external construct validity, by association with impairments and American College of Rheumatology functional stages. Cross-cultural validity is tested through DIF by comparison with data from the UK version of the HAQ. The adapted version of the HAQ demonstrated good internal construct validity through fit of the data to the Rasch model (mean item fit 0.205; SD 0.998). Reliability was excellent (alpha = 0.97) and external construct validity was confirmed by expected associations. DIF for culture was found in only 1 item. Cross-cultural validity was found to be sufficient for use in international studies between the UK and Turkey. Future adaptation of instruments should include analysis of DIF at the field testing stage in the adaptation process.

A validation of dynamic causal modelling for 7T fMRI.

PubMed

Tak, S; Noh, J; Cheong, C; Zeidman, P; Razi, A; Penny, W D; Friston, K J

2018-07-15

There is growing interest in ultra-high field magnetic resonance imaging (MRI) in cognitive and clinical neuroscience studies. However, the benefits offered by higher field strength have not been evaluated in terms of effective connectivity and dynamic causal modelling (DCM). In this study, we address the validity of DCM for 7T functional MRI data at two levels. First, we evaluate the predictive validity of DCM estimates based upon 3T and 7T in terms of reproducibility. Second, we assess improvements in the efficiency of DCM estimates at 7T, in terms of the entropy of the posterior distribution over model parameters (i.e., information gain). Using empirical data recorded during fist-closing movements with 3T and 7T fMRI, we found a high reproducibility of average connectivity and condition-specific changes in connectivity - as quantified by the intra-class correlation coefficient (ICC = 0.862 and 0.936, respectively). Furthermore, we found that the posterior entropy of 7T parameter estimates was substantially less than that of 3T parameter estimates; suggesting the 7T data are more informative - and furnish more efficient estimates. In the framework of DCM, we treated field-dependent parameters for the BOLD signal model as free parameters, to accommodate fMRI data at 3T and 7T. In addition, we made the resting blood volume fraction a free parameter, because different brain regions can differ in their vascularization. In this paper, we showed DCM enables one to infer changes in effective connectivity from 7T data reliably and efficiently. Copyright © 2018 Elsevier B.V. All rights reserved.

Molecular description of α-keto-based inhibitors of cruzain with activity against Chagas disease combining 3D-QSAR studies and molecular dynamics.

PubMed

Saraiva, Ádria P B; Miranda, Ricardo M; Valente, Renan P P; Araújo, Jéssica O; Souza, Rutelene N B; Costa, Clauber H S; Oliveira, Amanda R S; Almeida, Michell O; Figueiredo, Antonio F; Ferreira, João E V; Alves, Cláudio Nahum; Honorio, Kathia M

2018-04-22

In this work, a group of α-keto-based inhibitors of the cruzain enzyme with anti-chagas activity was selected for a three-dimensional quantitative structure-activity relationship study (3D-QSAR) combined with molecular dynamics (MD). Firstly, statistical models based on Partial Least Square (PLS) regression were developed employing comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) descriptors. Validation parameters (q 2 and r 2 )for the models were, respectively, 0.910 and 0.997 (CoMFA) and 0.913 and 0.992 (CoMSIA). In addition, external validation for the models using a test group revealed r 2 pred  = 0.728 (CoMFA) and 0.971 (CoMSIA). The most relevant aspect in this study was the generation of molecular fields in both favorable and unfavorable regions based on the models developed. These fields are important to interpret modifications necessary to enhance the biological activities of the inhibitors. This analysis was restricted considering the inhibitors in a fixed conformation, not interacting with their target, the cruzain enzyme. Then, MD was employed taking into account important variables such as time and temperature. MD helped describe the behavior of the inhibitors and their properties showed similar results as those generated by QSAR-3D study. © 2018 John Wiley & Sons A/S.

Interpretation of the electric fields measured in an ionospheric critical ionization velocity experiment

NASA Technical Reports Server (NTRS)

Brenning, N.; Faelthammar, C.-G.; Marklund, G.; Haerendel, G.; Kelley, M. C.; Pfaff, R.

1991-01-01

The quasi-dc electric fields measured in the CRIT I ionospheric release experiment are studied. In the experiment, two identical barium shaped charges were fired toward a main payload, and three-dimensional measurements of the electric field inside the streams were made. The relevance of proposed mechanisms for electron heating in the critical ionization velocity (CIV) mechanism is addressed. It is concluded that both the 'homogeneous' and the 'ionizing front' models probably are valid, but in different parts of the streams. It is also possible that electrons are directly accelerated by a magnetic field-aligned component of the electric field. The coupling between the ambient ionosphere and the ionized barium stream is more complicated that is usually assumed in CIV theories, with strong magnetic-field-aligned electric fields and probably current limitation as important processes.

Applying the Inverse Maximum Ratio- Λ to 3-Dimensional Surfaces

NASA Astrophysics Data System (ADS)

Chandran, Avinash; Brown, Derek; DiPietro, Loretta; Danoff, Jerome

2016-06-01

The question of contour uniformity on a three-dimensional surface arises in various fields of study. Although many questions related to surface uniformity exist, there is a lack of standard methodology to quantify uniformity of a three-dimensional surface. Therefore, a sound mathematical approach to this question could prove to be useful in various areas of study. The purpose of this paper is to expand the previously validated mathematical concept of the inverse maximum ratio over a three-dimensional surface and assess its robustness. We will describe the mathematical approach used to accomplish this and use several simulated examples to validate the metric.

Validation of a 2 percent lactic acid antimicrobial rinse for mobile poultry slaughter operations.

PubMed

Killinger, Karen M; Kannan, Aditi; Bary, Andy I; Cogger, Craig G

2010-11-01

Poultry processing antimicrobial interventions are critical for pathogen control, and organic, mobile operations in Washington seek alternatives to chlorine. Laboratory and field studies (three replications each) evaluated lactic acid efficacy as a chlorine alternative. For the laboratory study, retail-purchased, conventionally processed chicken wings inoculated with Salmonella were randomly assigned to the following treatments: Salmonella inoculation followed by no treatment (10 wings) or by 3-min rinses of water, 50 to 100 ppm of chlorine, or 2% lactic acid (20 wings for each rinse treatment). Wings were sampled for Salmonella enumeration on xylose lysine desoxycholate agar. During pastured poultry processing at mobile slaughter units for each field study replication, 20 chicken carcasses were randomly assigned to each treatment: untreated control or 3-min immersion in lactic acid or chlorine. Whole-carcass rinses were examined for aerobic plate count (APC) on tryptic soy agar and coliforms on violet red bile agar. Untreated controls were also examined for Salmonella. In the laboratory study, lactic acid produced a significant (P < 0.01) Salmonella reduction compared with the inoculated no-rinse, water, and chlorine treatments, which were statistically similar to each other. In the field study, no Salmonella was detected on untreated controls. Lactic acid produced significant >2-log (P < 0.01) reductions in APC and coliforms, whereas chlorine resulted in slight, but significant 0.4-log reductions (P < 0.01) and 0.21-log reductions (P < 0.05) in APC and coliforms compared with untreated controls. Considering laboratory and field studies, lactic acid produced greater reductions in Salmonella, APC, and coliforms, validating its effectiveness as a chlorine alternative in mobile poultry slaughter operations.

The Brownian mean field model

NASA Astrophysics Data System (ADS)

Chavanis, Pierre-Henri

2014-05-01

We discuss the dynamics and thermodynamics of the Brownian mean field (BMF) model which is a system of N Brownian particles moving on a circle and interacting via a cosine potential. It can be viewed as the canonical version of the Hamiltonian mean field (HMF) model. The BMF model displays a second order phase transition from a homogeneous phase to an inhomogeneous phase below a critical temperature T c = 1 / 2. We first complete the description of this model in the mean field approximation valid for N → +∞. In the strong friction limit, the evolution of the density towards the mean field Boltzmann distribution is governed by the mean field Smoluchowski equation. For T < T c , this equation describes a process of self-organization from a non-magnetized (homogeneous) phase to a magnetized (inhomogeneous) phase. We obtain an analytical expression for the temporal evolution of the magnetization close to T c . Then, we take fluctuations (finite N effects) into account. The evolution of the density is governed by the stochastic Smoluchowski equation. From this equation, we derive a stochastic equation for the magnetization and study its properties both in the homogenous and inhomogeneous phase. We show that the fluctuations diverge at the critical point so that the mean field approximation ceases to be valid. Actually, the limits N → +∞ and T → T c do not commute. The validity of the mean field approximation requires N( T - T c ) → +∞ so that N must be larger and larger as T approaches T c . We show that the direction of the magnetization changes rapidly close to T c while its amplitude takes a long time to relax. We also indicate that, for systems with long-range interactions, the lifetime of metastable states scales as e N except close to a critical point. The BMF model shares many analogies with other systems of Brownian particles with long-range interactions such as self-gravitating Brownian particles, the Keller-Segel model describing the chemotaxis of bacterial populations, the Kuramoto model describing the collective synchronization of coupled oscillators, the Desai-Zwanzig model, and the models describing the collective motion of social organisms such as bird flocks or fish schools.

A calibration protocol for population-specific accelerometer cut-points in children.

PubMed

Mackintosh, Kelly A; Fairclough, Stuart J; Stratton, Gareth; Ridgers, Nicola D

2012-01-01

To test a field-based protocol using intermittent activities representative of children's physical activity behaviours, to generate behaviourally valid, population-specific accelerometer cut-points for sedentary behaviour, moderate, and vigorous physical activity. Twenty-eight children (46% boys) aged 10-11 years wore a hip-mounted uniaxial GT1M ActiGraph and engaged in 6 activities representative of children's play. A validated direct observation protocol was used as the criterion measure of physical activity. Receiver Operating Characteristics (ROC) curve analyses were conducted with four semi-structured activities to determine the accelerometer cut-points. To examine classification differences, cut-points were cross-validated with free-play and DVD viewing activities. Cut-points of ≤ 372, >2160 and >4806 counts • min(-1) representing sedentary, moderate and vigorous intensity thresholds, respectively, provided the optimal balance between the related needs for sensitivity (accurately detecting activity) and specificity (limiting misclassification of the activity). Cross-validation data demonstrated that these values yielded the best overall kappa scores (0.97; 0.71; 0.62), and a high classification agreement (98.6%; 89.0%; 87.2%), respectively. Specificity values of 96-97% showed that the developed cut-points accurately detected physical activity, and sensitivity values (89-99%) indicated that minutes of activity were seldom incorrectly classified as inactivity. The development of an inexpensive and replicable field-based protocol to generate behaviourally valid and population-specific accelerometer cut-points may improve the classification of physical activity levels in children, which could enhance subsequent intervention and observational studies.

Inter-hemispheric interaction facilitates face processing.

PubMed

Compton, Rebecca J

2002-01-01

Many recent studies have revealed that interaction between the left and right cerebral hemispheres can aid in task performance, but these studies have tended to examine perception of simple stimuli such as letters, digits or simple shapes, which may have limited naturalistic validity. The present study extends these prior findings to a more naturalistic face perception task. Matching tasks required subjects to indicate when a target face matched one of two probe faces. Matches could be either across-field, requiring inter-hemispheric interaction, or within-field, not requiring inter-hemispheric interaction. Subjects indicated when faces matched in emotional expression (Experiment 1; n=32) or in character identity (Experiment 2; n=32). In both experiments, across-field performance was significantly better than within-field performance, supporting the primary hypothesis. Further, this advantage was greater for the more difficult character identity task. Results offer qualified support for the hypothesis that inter-hemispheric interaction is especially advantageous as task demands increase.

Electromagnetic field tapering using all-dielectric gradient index materials.

PubMed

Yi, Jianjia; Piau, Gérard-Pascal; de Lustrac, André; Burokur, Shah Nawaz

2016-07-28

The concept of transformation optics (TO) is applied to control the flow of electromagnetic fields between two sections of different dimensions through a tapering device. The broadband performance of the field taper is numerically and experimentally validated. The taper device presents a graded permittivity profile and is fabricated through three-dimensional (3D) polyjet printing technology using low-cost all-dielectric materials. Calculated and measured near-field mappings are presented in order to validate the proposed taper. A good qualitative agreement is obtained between full-wave simulations and experimental tests. Such all-dielectric taper paves the way to novel types of microwave devices that can be easily fabricated through low-cost additive manufacturing processes.

Field-Scale Soil Moisture Observations in Irrigated Agriculture Fields Using the Cosmic-ray Neutron Rover

NASA Astrophysics Data System (ADS)

Franz, T. E.; Avery, W. A.; Finkenbiner, C. E.; Wang, T.; Brocca, L.

2014-12-01

Approximately 40% of global food production comes from irrigated agriculture. With the increasing demand for food even greater pressures will be placed on water resources within these systems. In this work we aimed to characterize the spatial and temporal patterns of soil moisture at the field-scale (~500 m) using the newly developed cosmic-ray neutron rover near Waco, NE. Here we mapped soil moisture of 144 quarter section fields (a mix of maize, soybean, and natural areas) each week during the 2014 growing season (May to September). The 11 x11 km study domain also contained 3 stationary cosmic-ray neutron probes for independent validation of the rover surveys. Basic statistical analysis of the domain indicated a strong inverted parabolic relationship between the mean and variance of soil moisture. The relationship between the mean and higher order moments were not as strong. Geostatistical analysis indicated the range of the soil moisture semi-variogram was significantly shorter during periods of heavy irrigation as compared to non-irrigated periods. Scaling analysis indicated strong power law behavior between the variance of soil moisture and averaging area with minimal dependence of mean soil moisture on the slope of the power law function. Statistical relationships derived from the rover dataset offer a novel set of observations that will be useful in: 1) calibrating and validating land surface models, 2) calibrating and validating crop models, 3) soil moisture covariance estimates for statistical downscaling of remote sensing products such as SMOS and SMAP, and 4) provide center-pivot scale mean soil moisture data for optimal irrigation timing and volume amounts.

Exploring Techniques for Improving Retrievals of Bio-optical Properties of Coastal Waters

DTIC Science & Technology

2011-09-30

BRDF model was developed for coastal waters, and validated on the data of the two LISCO instruments, and its comparison with MODIS satellite imagery...in field conditions to validate radiative transfer modeling and assess possibilities for the separation of organic and inorganic particulate...to retrieve water components and compared with NOMAD and field CCNY data. Simulated datasets were also used to develop a BRDF model for coastal

Applications of GPS technologies to field sports.

PubMed

Aughey, Robert J

2011-09-01

Global positioning system (GPS) technology was made possible after the invention of the atomic clock. The first suggestion that GPS could be used to assess the physical activity of humans followed some 40 y later. There was a rapid uptake of GPS technology, with the literature concentrating on validation studies and the measurement of steady-state movement. The first attempts were made to validate GPS for field sport applications in 2006. While GPS has been validated for applications for team sports, some doubts continue to exist on the appropriateness of GPS for measuring short high-velocity movements. Thus, GPS has been applied extensively in Australian football, cricket, hockey, rugby union and league, and soccer. There is extensive information on the activity profile of athletes from field sports in the literature stemming from GPS, and this includes total distance covered by players and distance in velocity bands. Global positioning systems have also been applied to detect fatigue in matches, identify periods of most intense play, different activity profiles by position, competition level, and sport. More recent research has integrated GPS data with the physical capacity or fitness test score of athletes, game-specific tasks, or tactical or strategic information. The future of GPS analysis will involve further miniaturization of devices, longer battery life, and integration of other inertial sensor data to more effectively quantify the effort of athletes.

Nursing Informatics Competencies: Psychometric Validation, Dissemination, and Maintenance of Self-Assessment Tool for Nurse Leaders.

PubMed

Collins, Sarah

2016-01-01

Due to rapid advances in technology, HIT competencies for nursing leaders require frequent attention and updating from experts in the field to ensure relevance to nursing leaders' work. This workshop will target nursing informatics researchers and leaders to: 1) learn methods and findings from a study validating a Self-Assessment Scale for Nursing Informatics Competencies for Nurse Leaders, 2) generate awareness of the Self-Assessment scale, 3) discuss strategies for maintenance of competencies overtime and 4) identify strategies to engage nursing leaders in this pursuit.

Analytical and experimental validation of the Oblique Detonation Wave Engine concept

NASA Technical Reports Server (NTRS)

Adelman, Henry G.; Cambier, Jean-Luc; Menees, Gene P.; Balboni, John A.

1988-01-01

The Oblique Detonation Wave Engine (ODWE) for hypersonic flight has been analytically studied by NASA using the CFD codes which fully couple finite rate chemistry with fluid dynamics. Fuel injector designs investigated included wall and strut injectors, and the in-stream strut injectors were chosen to provide good mixing with minimal stagnation pressure losses. Plans for experimentally validating the ODWE concept in an arc-jet hypersonic wind tunnel are discussed. Measurements of the flow field properties behind the oblique wave will be compared to analytical predictions.

Neurobehavioral epidemiology: application in risk assessment.

PubMed Central

Grandjean, P; White, R F; Weihe, P

1996-01-01

Neurobehavioral epidemiology may contribute information to risk assessment in relation to a) characterization of neurotoxicity and its time course; b) the dose-effect relationship; c) the dose-response relationship; and d) predisposing factors. The quality of this information relies on the validity of the exposure data, the validity and sensitivity of neurobehavioral function tests, and the degree to which sources of bias are controlled. With epidemiologic studies of methylmercury-associated neurotoxicity as an example, the field of research involves numerous uncertainties that should be taken into account in the risk assessment process. PMID:9182047

Current Concerns in Validity Theory.

ERIC Educational Resources Information Center

Kane, Michael

Validity is concerned with the clarification and justification of the intended interpretations and uses of observed scores. It has not been easy to formulate a general methodology set of principles for validation, but progress has been made, especially as the field has moved from relatively limited criterion-related models to sophisticated…

Construction and Validation of a Professional Suitability Scale for Social Work Practice

ERIC Educational Resources Information Center

Tam, Dora M. Y.; Coleman, Heather

2009-01-01

This article reports on the construction and validation of a professional suitability scale, designed for assessing students' suitability for social work practice. Data were collected from 188 field supervisors who provided usable questionnaires, representing a response rate of 74%. Construct validation by exploratory factor analysis identified a…

Methodology for Computational Fluid Dynamic Validation for Medical Use: Application to Intracranial Aneurysm.

PubMed

Paliwal, Nikhil; Damiano, Robert J; Varble, Nicole A; Tutino, Vincent M; Dou, Zhongwang; Siddiqui, Adnan H; Meng, Hui

2017-12-01

Computational fluid dynamics (CFD) is a promising tool to aid in clinical diagnoses of cardiovascular diseases. However, it uses assumptions that simplify the complexities of the real cardiovascular flow. Due to high-stakes in the clinical setting, it is critical to calculate the effect of these assumptions in the CFD simulation results. However, existing CFD validation approaches do not quantify error in the simulation results due to the CFD solver's modeling assumptions. Instead, they directly compare CFD simulation results against validation data. Thus, to quantify the accuracy of a CFD solver, we developed a validation methodology that calculates the CFD model error (arising from modeling assumptions). Our methodology identifies independent error sources in CFD and validation experiments, and calculates the model error by parsing out other sources of error inherent in simulation and experiments. To demonstrate the method, we simulated the flow field of a patient-specific intracranial aneurysm (IA) in the commercial CFD software star-ccm+. Particle image velocimetry (PIV) provided validation datasets for the flow field on two orthogonal planes. The average model error in the star-ccm+ solver was 5.63 ± 5.49% along the intersecting validation line of the orthogonal planes. Furthermore, we demonstrated that our validation method is superior to existing validation approaches by applying three representative existing validation techniques to our CFD and experimental dataset, and comparing the validation results. Our validation methodology offers a streamlined workflow to extract the "true" accuracy of a CFD solver.

Software development predictors, error analysis, reliability models and software metric analysis

NASA Technical Reports Server (NTRS)

Basili, Victor

1983-01-01

The use of dynamic characteristics as predictors for software development was studied. It was found that there are some significant factors that could be useful as predictors. From a study on software errors and complexity, it was shown that meaningful results can be obtained which allow insight into software traits and the environment in which it is developed. Reliability models were studied. The research included the field of program testing because the validity of some reliability models depends on the answers to some unanswered questions about testing. In studying software metrics, data collected from seven software engineering laboratory (FORTRAN) projects were examined and three effort reporting accuracy checks were applied to demonstrate the need to validate a data base. Results are discussed.

Cross-Cultural Analyses of Determinants of Quality of Life and Mental Health: Results from the Eurohis Study

ERIC Educational Resources Information Center

Schmidt, Silke; Power, Mick

2006-01-01

Recent projects on international instrument development have produced a wide array of health indicators that may be used for cross-cultural field-testing, however more information on their cross-cultural performance in relation to health determinants is necessary. The current study approaches one step for international conceptual validation by…

Judgements about Knowledge: Searching for Factors that Influence Their Validity

ERIC Educational Resources Information Center

Mengelkamp, Christoph; Bannert, Maria

2009-01-01

Introduction: Research in the field of metacomprehension often uses the accuracy of judgements of own knowledge as a measure of monitoring which is a central component of metacognition. One aim of this study is to investigate if the accuracy above chance usually found in studies using traditional texts can be replicated with hypermedia. More…

Measuring Faculty Attitudes and Perceptions toward Disability at a Four-Year University: A Validity Study

ERIC Educational Resources Information Center

Lombardi, Allison

2010-01-01

The primary purpose of this study was to develop and field test the ExCEL survey instrument, intended to measure faculty attitudes toward and perceptions about students with disabilities at four-year colleges and universities. A secondary purpose was to examine how demographic characteristics of the sample and prior disability-focused training…

Exploring Vocational and Academic Fields of Study: Development and Validation of the Flemish SIMON Interest Inventory (SIMON-I)

ERIC Educational Resources Information Center

Fonteyne, Lot; Wille, Bart; Duyck, Wouter; De Fruyt, Filip

2017-01-01

A new, Holland-based Interest Inventory is proposed, intended to facilitate the transition from secondary to tertiary education. Specific interest items were designed to grasp activities that are prevalent during tertiary studies, including an Academic-track-scale to assist in the choice between academic and vocational-oriented programs. Interest…

Online Formative Assessments as Valid Correlates of Foreign Language Proficiency Levels as Measured by IL/DLPT5 Summative Tests

ERIC Educational Resources Information Center

Castro-Peet, Alma Sandra

2017-01-01

Purpose: This study explored a technological contribution to education made by the Defense Language Institute Foreign Language Center (DLIFLC) in the formative assessment field. The purpose of this quantitative correlational study was to identify the relationship between online formative (Online Diagnostic Assessment; ODA) and summative (Defense…

Bird Radar Validation in the Field by Time-Referencing Line-Transect Surveys

PubMed Central

Dokter, Adriaan M.; Baptist, Martin J.; Ens, Bruno J.; Krijgsveld, Karen L.; van Loon, E. Emiel

2013-01-01

Track-while-scan bird radars are widely used in ornithological studies, but often the precise detection capabilities of these systems are unknown. Quantification of radar performance is essential to avoid observational biases, which requires practical methods for validating a radar’s detection capability in specific field settings. In this study a method to quantify the detection capability of a bird radar is presented, as well a demonstration of this method in a case study. By time-referencing line-transect surveys, visually identified birds were automatically linked to individual tracks using their transect crossing time. Detection probabilities were determined as the fraction of the total set of visual observations that could be linked to radar tracks. To avoid ambiguities in assigning radar tracks to visual observations, the observer’s accuracy in determining a bird’s transect crossing time was taken into account. The accuracy was determined by examining the effect of a time lag applied to the visual observations on the number of matches found with radar tracks. Effects of flight altitude, distance, surface substrate and species size on the detection probability by the radar were quantified in a marine intertidal study area. Detection probability varied strongly with all these factors, as well as species-specific flight behaviour. The effective detection range for single birds flying at low altitude for an X-band marine radar based system was estimated at ∼1.5 km. Within this range the fraction of individual flying birds that were detected by the radar was 0.50±0.06 with a detection bias towards higher flight altitudes, larger birds and high tide situations. Besides radar validation, which we consider essential when quantification of bird numbers is important, our method of linking radar tracks to ground-truthed field observations can facilitate species-specific studies using surveillance radars. The methodology may prove equally useful for optimising tracking algorithms. PMID:24066103

Bird radar validation in the field by time-referencing line-transect surveys.

PubMed

Dokter, Adriaan M; Baptist, Martin J; Ens, Bruno J; Krijgsveld, Karen L; van Loon, E Emiel

2013-01-01

Track-while-scan bird radars are widely used in ornithological studies, but often the precise detection capabilities of these systems are unknown. Quantification of radar performance is essential to avoid observational biases, which requires practical methods for validating a radar's detection capability in specific field settings. In this study a method to quantify the detection capability of a bird radar is presented, as well a demonstration of this method in a case study. By time-referencing line-transect surveys, visually identified birds were automatically linked to individual tracks using their transect crossing time. Detection probabilities were determined as the fraction of the total set of visual observations that could be linked to radar tracks. To avoid ambiguities in assigning radar tracks to visual observations, the observer's accuracy in determining a bird's transect crossing time was taken into account. The accuracy was determined by examining the effect of a time lag applied to the visual observations on the number of matches found with radar tracks. Effects of flight altitude, distance, surface substrate and species size on the detection probability by the radar were quantified in a marine intertidal study area. Detection probability varied strongly with all these factors, as well as species-specific flight behaviour. The effective detection range for single birds flying at low altitude for an X-band marine radar based system was estimated at ~1.5 km. Within this range the fraction of individual flying birds that were detected by the radar was 0.50 ± 0.06 with a detection bias towards higher flight altitudes, larger birds and high tide situations. Besides radar validation, which we consider essential when quantification of bird numbers is important, our method of linking radar tracks to ground-truthed field observations can facilitate species-specific studies using surveillance radars. The methodology may prove equally useful for optimising tracking algorithms.

Light field reconstruction robust to signal dependent noise

NASA Astrophysics Data System (ADS)

Ren, Kun; Bian, Liheng; Suo, Jinli; Dai, Qionghai

2014-11-01

Capturing four dimensional light field data sequentially using a coded aperture camera is an effective approach but suffers from low signal noise ratio. Although multiplexing can help raise the acquisition quality, noise is still a big issue especially for fast acquisition. To address this problem, this paper proposes a noise robust light field reconstruction method. Firstly, scene dependent noise model is studied and incorporated into the light field reconstruction framework. Then, we derive an optimization algorithm for the final reconstruction. We build a prototype by hacking an off-the-shelf camera for data capturing and prove the concept. The effectiveness of this method is validated with experiments on the real captured data.

Broadband near-field mid-infrared spectroscopy and application to phonon resonances in quartz.

PubMed

Ishikawa, Michio; Katsura, Makoto; Nakashima, Satoru; Ikemoto, Yuka; Okamura, Hidekazu

2012-05-07

Infrared (IR) spectroscopy is a versatile analytical method and nano-scale spatial resolution could be achieved by scattering type near-field optical microscopy (s-SNOM). The spectral bandwidth was, however, limited to approximately 300 cm(-1) with a laser light source. In the present study, the development of a broadband mid-IR near-field spectroscopy with a ceramic light source is demonstrated. A much wider bandwidth (at least 3000 to 1000 cm(-1)) is achieved with a ceramic light source. The experimental data on quartz Si-O phonon resonance bands are well reproduced by theoretical simulations indicating the validity of the present broadband near-field IR spectroscopy.

Modeling of Focused Acoustic Field of a Concave Multi-annular Phased Array Using Spheroidal Beam Equation

NASA Astrophysics Data System (ADS)

Yu, Li-Li; Shou, Wen-De; Hui, Chun

2012-02-01

A theoretical model of focused acoustic field for a multi-annular phased array on concave spherical surface is proposed. In this model, the source boundary conditions of the spheroidal beam equation (SBE) for multi-annular phased elements are studied. Acoustic field calculated by the dynamic focusing model of SBE is compared with numerical results of the O'Neil and Khokhlov—Zabolotskaya—Kuznetsov (KZK) model, respectively. Axial dynamic focusing and the harmonic effects are presented. The results demonstrate that the dynamic focusing model of SBE is good valid for a concave multi-annular phased array with a large aperture angle in the linear or nonlinear field.

A Comparison of Physical Education Students’ Motivation Using Polish and Turkish Versions of the Academic Motivation Scale

PubMed Central

Tomik, Rajmund; Berber, Serkan; Düz, Burak; Çivak, Barış; Çalişkan, Uğur; Ogrodnik, Joanna

2016-01-01

Abstract Motivation is an important phenomenon in the realm of education, particularly in the university fields connected with physical education and sport, where it is necessary to accommodate and balance intellectual abilities and physical fitness. The present study tested motivation levels among university students in the fields connected with physical education and sport in Poland and Turkey. It was based on the Self-Determination Theory (Deci and Ryan, 1985), namely intrinsic motivation, extrinsic motivation and amotivation which impact human behaviour. The Academic Motivation Scale was used (Vallerand et al., 1992). The aims of the study were twofold, first, to crossculturally validate Polish and Turkish versions of the Academic Motivation Scale and second, to identify and compare the motivation to study depending on nationality and gender. Both Polish and Turkish versions of the questionnaire were validated and converted to a four-factorial structure. The findings indicated that Polish and Turkish students’ motivation especially differed in amotivation and intrinsic motivation to know and experience stimulation. Moreover, Turkish female students proved to be at the lowest estimate of amotivation. PMID:28031771

A Comparison of Physical Education Students' Motivation Using Polish and Turkish Versions of the Academic Motivation Scale.

PubMed

Ardeńska, Agnieszka; Tomik, Rajmund; Berber, Serkan; Düz, Burak; Çivak, Barış; Çalişkan, Uğur; Ogrodnik, Joanna

2016-12-01

Motivation is an important phenomenon in the realm of education, particularly in the university fields connected with physical education and sport, where it is necessary to accommodate and balance intellectual abilities and physical fitness. The present study tested motivation levels among university students in the fields connected with physical education and sport in Poland and Turkey. It was based on the Self-Determination Theory (Deci and Ryan, 1985), namely intrinsic motivation, extrinsic motivation and amotivation which impact human behaviour. The Academic Motivation Scale was used (Vallerand et al., 1992). The aims of the study were twofold, first, to crossculturally validate Polish and Turkish versions of the Academic Motivation Scale and second, to identify and compare the motivation to study depending on nationality and gender. Both Polish and Turkish versions of the questionnaire were validated and converted to a four-factorial structure. The findings indicated that Polish and Turkish students' motivation especially differed in amotivation and intrinsic motivation to know and experience stimulation. Moreover, Turkish female students proved to be at the lowest estimate of amotivation.

Study of the method of water-injected meat identifying based on low-field nuclear magnetic resonance

NASA Astrophysics Data System (ADS)

Xu, Jianmei; Lin, Qing; Yang, Fang; Zheng, Zheng; Ai, Zhujun

2018-01-01

The aim of this study to apply low-field nuclear magnetic resonance technique was to study regular variation of the transverse relaxation spectral parameters of water-injected meat with the proportion of water injection. Based on this, the method of one-way ANOVA and discriminant analysis was used to analyse the differences between these parameters in the capacity of distinguishing water-injected proportion, and established a model for identifying water-injected meat. The results show that, except for T 21b, T 22e and T 23b, the other parameters of the T 2 relaxation spectrum changed regularly with the change of water-injected proportion. The ability of different parameters to distinguish water-injected proportion was different. Based on S, P 22 and T 23m as the prediction variable, the Fisher model and the Bayes model were established by discriminant analysis method, qualitative and quantitative classification of water-injected meat can be realized. The rate of correct discrimination of distinguished validation and cross validation were 88%, the model was stable.

The assessment of creativity in creativity/psychopathology research - a systematic review.

PubMed

Thys, E; Sabbe, B; De Hert, M

2014-01-01

The possible link between creativity and psychopathology has been a long time focus of research up to the present day. However, this research is hampered by methodological problems, especially the definition and assessment of creativity. This makes interpretation and comparison of studies difficult and possibly accounts for the contradictory results of this research. In this systematic review of the literature, research articles in the field of creativity and psychopathology were searched for creativity assessment tools. The tools used in the collected articles are presented and discussed. The results indicate that a multitude of creativity assessment tools were used, that many studies only used one tool to assess creativity and that most of these tools were only used in a limited number of studies. A few assessment tools stand out by a more frequent use, also outside psychopathological research, and more solid psychometric properties. Most scales used to evaluate creativity have poor psychometric properties. The scattered methodology to assess creativity compromises the generalizability and validity of this research. The field should creatively develop new validated instruments.

High Fidelity Modeling of Field-Reversed Configuration (FRC) Thrusters (Briefing Charts)

DTIC Science & Technology

2017-05-24

Converged Math → Irrelevant Solutions? Validation: Fluids Example Stoke’s Flow MARTIN, SOUSA, TRAN (AFRL/RQRS) DISTRIBUTION A - APPROVED FOR PUBLIC RELEASE...Convergence Tests Converged Math → Irrelevant Solutions? Must be Aware of Valid Assumption Regions Validation: Fluids Example Stoke’s Flow Potential...AND VALIDATION Verification: Asymptotic Models → Analytical Solutions Yields Exact Convergence Tests Converged Math → Irrelevant Solutions? Must be

Automated Agricultural Field Extraction from Multi-temporal Web Enabled Landsat Data

NASA Astrophysics Data System (ADS)

Yan, L.; Roy, D. P.

2012-12-01

Agriculture has caused significant anthropogenic surface change. In many regions agricultural field sizes may be increasing to maximize yields and reduce costs resulting in decreased landscape spatial complexity and increased homogenization of land uses with potential for significant biogeochemical and ecological effects. To date, studies of the incidence, drivers and impacts of changing field sizes have not been undertaken over large areas because of computational constraints and because consistently processed appropriate resolution data have not been available or affordable. The Landsat series of satellites provides near-global coverage, long term, and appropriate spatial resolution (30m) satellite data to document changing field sizes. The recent free availability of all the Landsat data in the U.S. Landsat archive now provides the opportunity to study field size changes in a global and consistent way. Commercial software can be used to extract fields from Landsat data but are inappropriate for large area application because they require considerable human interaction. This paper presents research to develop and validate an automated computational Geographic Object Based Image Analysis methodology to extract agricultural fields and derive field sizes from Web Enabled Landsat Data (WELD) (http://weld.cr.usgs.gov/). WELD weekly products (30m reflectance and brightness temperature) are classified into Satellite Image Automatic Mapper™ (SIAM™) spectral categories and an edge intensity map and a map of the probability of each pixel being agricultural are derived from five years of 52 weeks of WELD and corresponding SIAM™ data. These data are fused to derive candidate agriculture field segments using a variational region-based geometric active contour model. Geometry-based algorithms are used to decompose connected segments belonging to multiple fields into coherent isolated field objects with a divide and conquer strategy to detect and merge partial circle segments. Results are presented for several 5000 x 5000 30m pixel WELD tiles encompassing rectangular and circular (pivot irrigation) fields in Texas and California and the results are validated qualitatively by comparison with high spatial resolution images obtained from the National Geospatial-Intelligence Agency (NGA) Commercial Archive. Implications and recommendations for algorithm refinement and application to decadal conterminous United States WELD data are discussed.

Land Surface Temperature Measurements from EOS MODIS Data

NASA Technical Reports Server (NTRS)

Wan, Zhengming

1997-01-01

We applied the multi-method strategy of land-surface temperature (LST) and emissivity measurements in two field campaigns this year for validating the MODIS LST algorithm. The first field campaign was conducted in Death Valley, CA, on March 3rd and the second one in Railroad Valley, NV, on June 23-27. ER2 MODIS Airborne Simulator (MAS) data were acquired in morning and evening for these two field campaigns. TIR spectrometer, radiometer, and thermistor data were also collected in the field campaigns. The LST values retrieved from MAS data with the day/night LST algorithm agree with those obtained from ground-based measurements within 1 C and show close correlations with topographic maps. The band emissivities retrieved from MAS data show close correlations with geological maps in the Death Valley field campaign. The comparison of measurement data in the latest Railroad Valley field campaign indicates that we are approaching the goals of the LST validation: LST uncertainty less than 0.5 C, and emissivity uncertainty less than 0.005 in the 10-13 spectral range. Measurement data show that the spatial variation in LST is the major uncertainty in the LST validation. In order to reduce this uncertainty, a new component of the multi-method strategy has been identified.

Reliability, validity and administrative burden of the community reintegration of injured service members computer adaptive test (CRIS-CAT)”

PubMed Central

2012-01-01

Background The Computer Adaptive Test version of the Community Reintegration of Injured Service Members measure (CRIS-CAT) consists of three scales measuring Extent of, Perceived Limitations in, and Satisfaction with community integration. The CRIS-CAT was developed using item response theory methods. The purposes of this study were to assess the reliability, concurrent, known group and predictive validity and respondent burden of the CRIS-CAT. The CRIS-CAT was developed using item response theory methods. The purposes of this study were to assess the reliability, concurrent, known group and predictive validity and respondent burden of the CRIS-CAT. Methods This was a three-part study that included a 1) a cross-sectional field study of 517 homeless, employed, and Operation Enduring Freedom / Operation Iraqi Freedom (OEF/OIF) Veterans; who completed all items in the CRIS item set, 2) a cohort study with one year follow-up study of 135 OEF/OIF Veterans, and 3) a 50-person study of CRIS-CAT administration. Conditional reliability of simulated CAT scores was calculated from the field study data, and concurrent validity and known group validity were examined using Pearson product correlations and ANOVAs. Data from the cohort were used to examine the ability of the CRIS-CAT to predict key one year outcomes. Data from the CRIS-CAT administration study were used to calculate ICC (2,1) minimum detectable change (MDC), and average number of items used during CAT administration. Results Reliability scores for all scales were above 0.75, but decreased at both ends of the score continuum. CRIS-CAT scores were correlated with concurrent validity indicators and differed significantly between the three Veteran groups (P < .001). The odds of having any Emergency Room visits were reduced for Veterans with better CRIS-CAT scores (Extent, Perceived Satisfaction respectively: OR = 0.94, 0.93, 0.95; P < .05). CRIS-CAT scores were predictive of SF-12 physical and mental health related quality of life scores at the 1 year follow-up. Scales had ICCs >0.9. MDCs were 5.9, 6.2, and 3.6, respectively for Extent, Perceived and Satisfaction subscales. Number of items (mn, SD) administered at Visit 1 were 14.6 (3.8) 10.9 (2.7) and 10.4 (1.7) respectively for Extent, Perceived and Satisfaction subscales. Conclusion The CRIS-CAT demonstrated sound measurement properties including reliability, construct, known group and predictive validity, and it was administered with minimal respondent burden. These findings support the use of this measure in assessing community reintegration. PMID:22984850

Evaluation of Mixed-Phase Microphysics Within Winter Storms using Field Data and In Situ Observations

NASA Technical Reports Server (NTRS)

Colle, Brian A.; Yu, Ruyi; Molthan, Andrew L.; Nesbitt, Stephen

2014-01-01

It is hypothesized that microphysical predictions have greater uncertainties/errors when there are complex interactions that result from mixedphased processes like riming. Use Global Precipitation Measurement (GPM) Mission ground validation studies in Ontario, Canada to verify and improve parameterizations

Validation of Health Services Careers Curriculum Manual.

ERIC Educational Resources Information Center

Stone, Sheila D.

This report is the result of a field test of "Health Service Careers" curriculum materials developed and published by the Curriculum and Instructional Materials Center, Oklahoma State Department of Vocational Technical Education. The results and conclusions reported in the study relate to student achievement and teacher evaluations and…

TEST METHODS TO DETERMINE THE MERCURY EMISSIONS FROM SLUDGE INCINERATION PLANTS

EPA Science Inventory

Two test methods for mercury are described along with the laboratory and field studies done in developing and validating them. One method describes how to homogenize and analyze large quantities of sewage sludge. The other test method describes how to measure the mercury emission...

Validating workplace performance assessments in health sciences students: a case study from speech pathology.

PubMed

McAllister, Sue; Lincoln, Michelle; Ferguson, Allison; McAllister, Lindy

2013-01-01

Valid assessment of health science students' ability to perform in the real world of workplace practice is critical for promoting quality learning and ultimately certifying students as fit to enter the world of professional practice. Current practice in performance assessment in the health sciences field has been hampered by multiple issues regarding assessment content and process. Evidence for the validity of scores derived from assessment tools are usually evaluated against traditional validity categories with reliability evidence privileged over validity, resulting in the paradoxical effect of compromising the assessment validity and learning processes the assessments seek to promote. Furthermore, the dominant statistical approaches used to validate scores from these assessments fall under the umbrella of classical test theory approaches. This paper reports on the successful national development and validation of measures derived from an assessment of Australian speech pathology students' performance in the workplace. Validation of these measures considered each of Messick's interrelated validity evidence categories and included using evidence generated through Rasch analyses to support score interpretation and related action. This research demonstrated that it is possible to develop an assessment of real, complex, work based performance of speech pathology students, that generates valid measures without compromising the learning processes the assessment seeks to promote. The process described provides a model for other health professional education programs to trial.

Tests for the Assessment of Sport-Specific Performance in Olympic Combat Sports: A Systematic Review With Practical Recommendations.

PubMed

Chaabene, Helmi; Negra, Yassine; Bouguezzi, Raja; Capranica, Laura; Franchini, Emerson; Prieske, Olaf; Hbacha, Hamdi; Granacher, Urs

2018-01-01

The regular monitoring of physical fitness and sport-specific performance is important in elite sports to increase the likelihood of success in competition. This study aimed to systematically review and to critically appraise the methodological quality, validation data, and feasibility of the sport-specific performance assessment in Olympic combat sports like amateur boxing, fencing, judo, karate, taekwondo, and wrestling. A systematic search was conducted in the electronic databases PubMed, Google-Scholar, and Science-Direct up to October 2017. Studies in combat sports were included that reported validation data (e.g., reliability, validity, sensitivity) of sport-specific tests. Overall, 39 studies were eligible for inclusion in this review. The majority of studies (74%) contained sample sizes <30 subjects. Nearly, 1/3 of the reviewed studies lacked a sufficient description (e.g., anthropometrics, age, expertise level) of the included participants. Seventy-two percent of studies did not sufficiently report inclusion/exclusion criteria of their participants. In 62% of the included studies, the description and/or inclusion of a familiarization session (s) was either incomplete or not existent. Sixty-percent of studies did not report any details about the stability of testing conditions. Approximately half of the studies examined reliability measures of the included sport-specific tests (intraclass correlation coefficient [ICC] = 0.43-1.00). Content validity was addressed in all included studies, criterion validity (only the concurrent aspect of it) in approximately half of the studies with correlation coefficients ranging from r = -0.41 to 0.90. Construct validity was reported in 31% of the included studies and predictive validity in only one. Test sensitivity was addressed in 13% of the included studies. The majority of studies (64%) ignored and/or provided incomplete information on test feasibility and methodological limitations of the sport-specific test. In 28% of the included studies, insufficient information or a complete lack of information was provided in the respective field of the test application. Several methodological gaps exist in studies that used sport-specific performance tests in Olympic combat sports. Additional research should adopt more rigorous validation procedures in the application and description of sport-specific performance tests in Olympic combat sports.

Commercially available gaming systems as clinical assessment tools to improve value in the orthopaedic setting: a systematic review.

PubMed

Ruff, Jessica; Wang, Tiffany L; Quatman-Yates, Catherine C; Phieffer, Laura S; Quatman, Carmen E

2015-02-01

Commercially available gaming systems (CAGS) such as the Wii Balance Board (WBB) and Microsoft Xbox with Kinect (Xbox Kinect) are increasingly used as balance training and rehabilitation tools. The purpose of this review was to answer the question, "Are commercially available gaming systems valid and reliable instruments for use as clinical diagnostic and functional assessment tools in orthopaedic settings?" and provide a summary of relevant studies, identify their strengths and weaknesses, and generate conclusions regarding general validity/reliability of WBB and Xbox Kinect in orthopaedics. A systematic search was performed using MEDLINE (1996-2013) and Scopus (1996-2013). Inclusion criteria were minimum of 5 subjects, full manuscript provided in English or translated, and studies incorporating investigation of CAG measurement properties. Exclusion criteria included reviews, systematic reviews, summary/clinical commentaries, or case studies; conference proceedings/presentations; cadaveric studies; studies of non-reversible, non-orthopaedic-related musculoskeletal disease; non-human trials; and therapeutic studies not reporting comparative evaluation to already established functional assessment criteria. All studies meeting inclusion and exclusion criteria were appraised for quality by two independent reviewers. Evidence levels (I-V) were assigned to each study based on established methodological criteria. 3 Level II, 7 level III, and 1 Level IV studies met inclusion criteria and provided information related to the use of the WBB and Xbox Kinect as clinical assessment tools in the field of orthopaedics. Studies have used the WBB in a variety of clinical applications, including the measurement of center of pressure (COP), measurement of medial-to-lateral (M/L) or anterior-to-posterior (A/P) symmetry, assessment anatomic landmark positioning, and assessment of fall risk. However, no uniform protocols or outcomes were used to evaluate the quality of the WBB as a clinical assessment tool; therefore a wide range of sensitivities, specificities, accuracies, and validities were reported. Currently it is not possible to make a universal generalization about the clinical utility of CAGS in the field of orthopaedics. However, there is evidence to support using the WBB and the Xbox Kinect as tools to obtain reliable and valid COP measurements. The Wii Fit Game may specifically provide reliable and valid measurements for predicting fall risk. Copyright © 2014 Elsevier Ltd. All rights reserved.

Organizational readiness for implementing change: a psychometric assessment of a new measure.

PubMed

Shea, Christopher M; Jacobs, Sara R; Esserman, Denise A; Bruce, Kerry; Weiner, Bryan J

2014-01-10

Organizational readiness for change in healthcare settings is an important factor in successful implementation of new policies, programs, and practices. However, research on the topic is hindered by the absence of a brief, reliable, and valid measure. Until such a measure is developed, we cannot advance scientific knowledge about readiness or provide evidence-based guidance to organizational leaders about how to increase readiness. This article presents results of a psychometric assessment of a new measure called Organizational Readiness for Implementing Change (ORIC), which we developed based on Weiner's theory of organizational readiness for change. We conducted four studies to assess the psychometric properties of ORIC. In study one, we assessed the content adequacy of the new measure using quantitative methods. In study two, we examined the measure's factor structure and reliability in a laboratory simulation. In study three, we assessed the reliability and validity of an organization-level measure of readiness based on aggregated individual-level data from study two. In study four, we conducted a small field study utilizing the same analytic methods as in study three. Content adequacy assessment indicated that the items developed to measure change commitment and change efficacy reflected the theoretical content of these two facets of organizational readiness and distinguished the facets from hypothesized determinants of readiness. Exploratory and confirmatory factor analysis in the lab and field studies revealed two correlated factors, as expected, with good model fit and high item loadings. Reliability analysis in the lab and field studies showed high inter-item consistency for the resulting individual-level scales for change commitment and change efficacy. Inter-rater reliability and inter-rater agreement statistics supported the aggregation of individual level readiness perceptions to the organizational level of analysis. This article provides evidence in support of the ORIC measure. We believe this measure will enable testing of theories about determinants and consequences of organizational readiness and, ultimately, assist healthcare leaders to reduce the number of health organization change efforts that do not achieve desired benefits. Although ORIC shows promise, further assessment is needed to test for convergent, discriminant, and predictive validity.

Organizational readiness for implementing change: a psychometric assessment of a new measure

PubMed Central

2014-01-01

Background Organizational readiness for change in healthcare settings is an important factor in successful implementation of new policies, programs, and practices. However, research on the topic is hindered by the absence of a brief, reliable, and valid measure. Until such a measure is developed, we cannot advance scientific knowledge about readiness or provide evidence-based guidance to organizational leaders about how to increase readiness. This article presents results of a psychometric assessment of a new measure called Organizational Readiness for Implementing Change (ORIC), which we developed based on Weiner’s theory of organizational readiness for change. Methods We conducted four studies to assess the psychometric properties of ORIC. In study one, we assessed the content adequacy of the new measure using quantitative methods. In study two, we examined the measure’s factor structure and reliability in a laboratory simulation. In study three, we assessed the reliability and validity of an organization-level measure of readiness based on aggregated individual-level data from study two. In study four, we conducted a small field study utilizing the same analytic methods as in study three. Results Content adequacy assessment indicated that the items developed to measure change commitment and change efficacy reflected the theoretical content of these two facets of organizational readiness and distinguished the facets from hypothesized determinants of readiness. Exploratory and confirmatory factor analysis in the lab and field studies revealed two correlated factors, as expected, with good model fit and high item loadings. Reliability analysis in the lab and field studies showed high inter-item consistency for the resulting individual-level scales for change commitment and change efficacy. Inter-rater reliability and inter-rater agreement statistics supported the aggregation of individual level readiness perceptions to the organizational level of analysis. Conclusions This article provides evidence in support of the ORIC measure. We believe this measure will enable testing of theories about determinants and consequences of organizational readiness and, ultimately, assist healthcare leaders to reduce the number of health organization change efforts that do not achieve desired benefits. Although ORIC shows promise, further assessment is needed to test for convergent, discriminant, and predictive validity. PMID:24410955

Radiation and matter: Electrodynamics postulates and Lorenz gauge

NASA Astrophysics Data System (ADS)

Bobrov, V. B.; Trigger, S. A.; van Heijst, G. J.; Schram, P. P.

2016-11-01

In general terms, we have considered matter as the system of charged particles and quantized electromagnetic field. For consistent description of the thermodynamic properties of matter, especially in an extreme state, the problem of quantization of the longitudinal and scalar potentials should be solved. In this connection, we pay attention that the traditional postulates of electrodynamics, which claim that only electric and magnetic fields are observable, is resolved by denial of the statement about validity of the Maxwell equations for microscopic fields. The Maxwell equations, as the generalization of experimental data, are valid only for averaged values. We show that microscopic electrodynamics may be based on postulation of the d'Alembert equations for four-vector of the electromagnetic field potential. The Lorenz gauge is valid for the averages potentials (and provides the implementation of the Maxwell equations for averages). The suggested concept overcomes difficulties under the electromagnetic field quantization procedure being in accordance with the results of quantum electrodynamics. As a result, longitudinal and scalar photons become real rather than virtual and may be observed in principle. The longitudinal and scalar photons provide not only the Coulomb interaction of charged particles, but also allow the electrical Aharonov-Bohm effect.

Validation of a moral distress instrument in nurses of primary health care 1

PubMed Central

Barth, Priscila Orlandi; Ramos, Flávia Regina Souza; Barlem, Edison Luiz Devos; Dalmolin, Graziele de Lima; Schneider, Dulcinéia Ghizoni

2018-01-01

ABSTRACT Objective: to validate an instrument to identify situations that trigger moral distress in relation to intensity and frequency in primary health care nurses. Method: this is a methodological study carried out with 391 nurses of primary health care, applied to the Brazilian Scale of Moral Distress in Nurses with 57 questions. Validation for primary health care was performed through expert committee evaluation, pre-test, factorial analysis, and Cronbach’s alpha. Results: there were 46 questions validated divided into six constructs: Health Policies, Working Conditions, Nurse Autonomy, Professional ethics, Disrespect to patient autonomy and Work Overload. The instrument had satisfactory internal consistency, with Cronbach’s alpha 0.98 for the instrument, and between 0.96 and 0.88 for the constructs. Conclusion: the instrument is valid and reliable to be used in the identification of the factors that trigger moral distress in primary care nurses, providing subsidies for new research in this field of professional practice. PMID:29791671

Reliability and Validity of the Lichtenberg Financial Decision Screening Scale.

PubMed

Lichtenberg, Peter A; Teresi, Jeanne A; Ocepek-Welikson, Katja; Eimicke, Joseph P

2017-03-01

The scarcity of empirically validated assessment instruments continues to impede the work of professionals in a number of fields, including medicine, finance, and estate planning; adult protective services; and criminal justice-and, more importantly, it impedes their ability to effectively assist and, in some case, protect their clients. Other professionals (e.g. legal, financial, medical, mental health services) are in a position to prevent financial exploitation and would benefit from access to new instruments. The Lichtenberg Financial Decision Screening Scale (LFDSS) was introduced in 2016, along with evidence for its convergent validity (Lichtenberg et al., 2016). Using a sample of 213 participants, this study investigated the internal consistency of the LFDSS and its criterion validity based on ratings by professionals using the scale. Results demonstrate that the LFDSS has excellent internal consistency and clinical utility properties. This paper provides support for use of the LFDSS as a reliable and valid instrument. The LFDSS and instructions for its use are included in the article, along with information about online tools and support.

Simulation studies of nucleation of ferroelectric polarization reversal.

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

Brennecka, Geoffrey L.; Winchester, Benjamin Michael

2014-08-01

Electric field-induced reversal of spontaneous polarization is the defining characteristic of a ferroelectric material, but the process(es) and mechanism(s) associated with the initial nucleation of reverse-polarity domains are poorly understood. This report describes studies carried out using phase field modeling of LiTaO 3, a relatively simple prototype ferroelectric material, in order to explore the effects of either mechanical deformation or optically-induced free charges on nucleation and resulting domain configuration during field-induced polarization reversal. Conditions were selected to approximate as closely as feasible those of accompanying experimental work in order to provide not only support for the experimental work but alsomore » ensure that additional experimental validation of the simulations could be carried out in the future. Phase field simulations strongly support surface mechanical damage/deformation as effective for dramatically reducing the overall coercive field (Ec) via local field enhancements. Further, optically-nucleated polarization reversal appears to occur via stabilization of latent nuclei via the charge screening effects of free charges.« less

Development, validation and field evaluation of a quantitative real-time PCR able to differentiate between field Mycoplasma synoviae and the MS-H-live vaccine strain.

PubMed

Dijkman, R; Feberwee, A; Landman, W J M

2017-08-01

A quantitative PCR (qPCR) able to differentiate between field Mycoplasma synoviae and MS-H vaccine strain was developed, validated and evaluated. It was developed using nucleotide differences in the obg gene. Analytical specificity and sensitivity assessed using DNA from 194 M. synoviae field samples, three different batches of MS-H vaccine and from 43 samples representing four other avian Mycoplasma species proved to be 100%. The detection limit for field M. synoviae and MS-H vaccine strain was 10 2-3 and 10 2 colony-forming units PCR equivalents/g trachea mucus, respectively. The qPCR was able to detect both, field M. synoviae and MS-H vaccine strain in ratios of 1:100 determined both using spiked and field samples. One hundred and twenty samples from M. synoviae-infected non-vaccinated birds, 110 samples from M. synoviae-vaccinated birds from a bird experiment and 224 samples from M. synoviae negative (serology and PCR) birds were used to determine the relative sensitivity and specificity using a previously described M. synoviae PCR as reference. The relative sensitivity and specificity for field M. synoviae were 95.0% and 99.6%, respectively, and 94.6% and 100% for the MS-H-live vaccine, respectively. Field validation and confirmation by multi locus sequence typing revealed that the qPCR correctly distinguished between MS-H and field M. synoviae. Evaluation of the differentiating M. synoviae qPCR in three commercial flocks suggested transmission of MS-H-live vaccine from vaccinated to non-vaccinated flocks at the same farm. Furthermore, it showed evidence for the colonization with field M. synoviae in MS-H-vaccinated flocks.

Experimental Validation of Lightning-Induced Electromagnetic (Indirect) Coupling to Short Monopole Antennas

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

Crull, E W; Brown Jr., C G; Perkins, M P

2008-07-30

For short monopoles in this low-power case, it has been shown that a simple circuit model is capable of accurate predictions for the shape and magnitude of the antenna response to lightning-generated electric field coupling effects, provided that the elements of the circuit model have accurate values. Numerical EM simulation can be used to provide more accurate values for the circuit elements than the simple analytical formulas, since the analytical formulas are used outside of their region of validity. However, even with the approximate analytical formulas the simple circuit model produces reasonable results, which would improve if more accurate analyticalmore » models were used. This report discusses the coupling analysis approaches taken to understand the interaction between a time-varying EM field and a short monopole antenna, within the context of lightning safety for nuclear weapons at DOE facilities. It describes the validation of a simple circuit model using laboratory study in order to understand the indirect coupling of energy into a part, and the resulting voltage. Results show that in this low-power case, the circuit model predicts peak voltages within approximately 32% using circuit component values obtained from analytical formulas and about 13% using circuit component values obtained from numerical EM simulation. We note that the analytical formulas are used outside of their region of validity. First, the antenna is insulated and not a bare wire and there are perhaps fringing field effects near the termination of the outer conductor that the formula does not take into account. Also, the effective height formula is for a monopole directly over a ground plane, while in the time-domain measurement setup the monopole is elevated above the ground plane by about 1.5-inch (refer to Figure 5).« less

Validation of Dosimetric Leaf Gap (DLG) prior to its implementation in Treatment Planning System (TPS): TrueBeam™ millennium 120 leaf MLC.

PubMed

Shende, Ravindra; Patel, Ganesh

2017-01-01

Objective of present study is to determine optimum value of DLG and its validation prior to being incorporated in TPS for Varian TrueBeam™ millennium 120 leaves MLC. Partial transmission through the rounded leaf ends of the Multi Leaf Collimator (MLC) causes a conflict between the edges of the light field and radiation field. Parameter account for this partial transmission is called Dosimetric Leaf Gap (DLG). The complex high precession technique, such as Intensity Modulated Radiation Therapy (IMRT), entails the modeling of optimum value of DLG inside Eclipse Treatment Planning System (TPS) for precise dose calculation. Distinct synchronized uniformed extension of sweeping dynamic MLC leaf gap fields created by Varian MLC shaper software were use to determine DLG. DLG measurements performed with both 0.13 cc semi-flex ionization chamber and 2D-Array I-Matrix were used to validate the DLG; similarly, values of DLG from TPS were estimated from predicted dose. Similar mathematical approaches were employed to determine DLG from delivered and TPS predicted dose. DLG determined from delivered dose measured with both ionization chamber (DLG Ion ) and I-Matrix (DLG I-Matrix ) compared with DLG estimate from TPS predicted dose (DLG TPS ). Measurements were carried out for all available 6MV, 10MV, 15MV, 6MVFFF and 10MVFFF beam energies. Maximum and minimum DLG deviation between measured and TPS calculated DLG was found to be 0.2 mm and 0.1 mm, respectively. Both of the measured DLGs (DLG Ion and DLG I-Matrix ) were found to be in a very good agreement with estimated DLG from TPS (DLG TPS ). Proposed method proved to be helpful in verifying and validating the DLG value prior to its clinical implementation in TPS.

Validation of the Vanderbilt Holistic Face Processing Test.

PubMed

Wang, Chao-Chih; Ross, David A; Gauthier, Isabel; Richler, Jennifer J

2016-01-01

The Vanderbilt Holistic Face Processing Test (VHPT-F) is a new measure of holistic face processing with better psychometric properties relative to prior measures developed for group studies (Richler et al., 2014). In fields where psychologists study individual differences, validation studies are commonplace and the concurrent validity of a new measure is established by comparing it to an older measure with established validity. We follow this approach and test whether the VHPT-F measures the same construct as the composite task, which is group-based measure at the center of the large literature on holistic face processing. In Experiment 1, we found a significant correlation between holistic processing measured in the VHPT-F and the composite task. Although this correlation was small, it was comparable to the correlation between holistic processing measured in the composite task with the same faces, but different target parts (top or bottom), which represents a reasonable upper limit for correlations between the composite task and another measure of holistic processing. These results confirm the validity of the VHPT-F by demonstrating shared variance with another measure of holistic processing based on the same operational definition. These results were replicated in Experiment 2, but only when the demographic profile of our sample matched that of Experiment 1.

Validation of the Vanderbilt Holistic Face Processing Test

PubMed Central

Wang, Chao-Chih; Ross, David A.; Gauthier, Isabel; Richler, Jennifer J.

2016-01-01

The Vanderbilt Holistic Face Processing Test (VHPT-F) is a new measure of holistic face processing with better psychometric properties relative to prior measures developed for group studies (Richler et al., 2014). In fields where psychologists study individual differences, validation studies are commonplace and the concurrent validity of a new measure is established by comparing it to an older measure with established validity. We follow this approach and test whether the VHPT-F measures the same construct as the composite task, which is group-based measure at the center of the large literature on holistic face processing. In Experiment 1, we found a significant correlation between holistic processing measured in the VHPT-F and the composite task. Although this correlation was small, it was comparable to the correlation between holistic processing measured in the composite task with the same faces, but different target parts (top or bottom), which represents a reasonable upper limit for correlations between the composite task and another measure of holistic processing. These results confirm the validity of the VHPT-F by demonstrating shared variance with another measure of holistic processing based on the same operational definition. These results were replicated in Experiment 2, but only when the demographic profile of our sample matched that of Experiment 1. PMID:27933014

Oral Biofluid Biomarker Research: Current Status and Emerging Frontiers

PubMed Central

Wang, Austin; Wang, Chris P.; Tu, Michael; Wong, David T.W.

2016-01-01

Salivary diagnostics is a rapidly advancing field that offers clinicians and patients the potential of rapid, noninvasive diagnostics with excellent accuracy. In order for the complete realization of the potential of saliva, however, extensive profiling of constituents must be conducted and diagnostic biomarkers must be thoroughly validated. This article briefly overviews the process of conducting a study of salivary biomarkers in a patient cohort and highlights the studies that have been conducted on different classes of molecules in the saliva. Emerging frontiers in salivary diagnostics research that may significantly advance the field will also be highlighted. PMID:27999326

An experimental study of the validity of the heat-field concept for sonic-boom alleviation

NASA Technical Reports Server (NTRS)

Swigart, R. J.

1974-01-01

An experimental program was carried out in the NASA-Langley 4 ft x 4 ft supersonic pressure tunnel to investigate the validity of the heat-field concept for sonic boom alleviation. The concept involves heating the flow about a supersonic aircraft in such a manner as to obtain an increase in effective aircraft length and yield an effective aircraft shape that will result in a shock-free pressure signature on the ground. First, a basic body-of-revolution representing an SST configuration with its lift equivalence in volume was tested to provide a baseline pressure signature. Second, a model having a 5/2-power area distribution which, according to theory, should yield a linear pressure rise with no front shock wave was tested. Third, the concept of providing the 5/2-power area distribution by using an off-axis slender fin below the basic body was investigated. Then a substantial portion (approximately 40 percent) of the solid fin was replaced by a heat field generated by passing heated nitrogen through the rear of the fin.

Simulation studies for the evaluation of health information technologies: experiences and results.

PubMed

Ammenwerth, Elske; Hackl, Werner O; Binzer, Kristine; Christoffersen, Tue E H; Jensen, Sanne; Lawton, Kitta; Skjoet, Peter; Nohr, Christian

It is essential for new health information technologies (IT) to undergo rigorous evaluations to ensure they are effective and safe for use in real-world situations. However, evaluation of new health IT is challenging, as field studies are often not feasible when the technology being evaluated is not sufficiently mature. Laboratory-based evaluations have also been shown to have insufficient external validity. Simulation studies seem to be a way to bridge this gap. The aim of this study was to evaluate, using a simulation methodology, the impact of a new prototype of an electronic medication management system on the appropriateness of prescriptions and drug-related activities, including laboratory test ordering or medication changes. This article presents the results of a controlled simulation study with 50 simulation runs, including ten doctors and five simulation patients, and discusses experiences and lessons learnt while conducting the study. Although the new electronic medication management system showed tendencies to improve medication safety when compared with the standard system, this tendency was not significant. Altogether, five distinct situations were identified where the new medication management system did help to improve medication safety. This simulation study provided a good compromise between internal validity and external validity. However, several challenges need to be addressed when undertaking simulation evaluations including: preparation of adequate test cases; training of participants before using unfamiliar applications; consideration of time, effort and costs of conducting the simulation; technical maturity of the evaluated system; and allowing adequate preparation of simulation scenarios and simulation setting. Simulation studies are an interesting but time-consuming approach, which can be used to evaluate newly developed health IT systems, particularly those systems that are not yet sufficiently mature to undergo field evaluation studies.

The Relationship Between Perceptual Egocentrism and Field Dependence in Early Childhood

ERIC Educational Resources Information Center

Bowd, Alan D.

1975-01-01

Kindergarten children were administered tests of inductive reasoning and field dependence and a series of perceptual egocentrism tasks. Results confirm a positive relation between field dependence and perceptual egocentrism; they also question the validity of the field-dependence construct in early childhood. (GO)

Adaptive vector validation in image velocimetry to minimise the influence of outlier clusters

NASA Astrophysics Data System (ADS)

Masullo, Alessandro; Theunissen, Raf

2016-03-01

The universal outlier detection scheme (Westerweel and Scarano in Exp Fluids 39:1096-1100, 2005) and the distance-weighted universal outlier detection scheme for unstructured data (Duncan et al. in Meas Sci Technol 21:057002, 2010) are the most common PIV data validation routines. However, such techniques rely on a spatial comparison of each vector with those in a fixed-size neighbourhood and their performance subsequently suffers in the presence of clusters of outliers. This paper proposes an advancement to render outlier detection more robust while reducing the probability of mistakenly invalidating correct vectors. Velocity fields undergo a preliminary evaluation in terms of local coherency, which parametrises the extent of the neighbourhood with which each vector will be compared subsequently. Such adaptivity is shown to reduce the number of undetected outliers, even when implemented in the afore validation schemes. In addition, the authors present an alternative residual definition considering vector magnitude and angle adopting a modified Gaussian-weighted distance-based averaging median. This procedure is able to adapt the degree of acceptable background fluctuations in velocity to the local displacement magnitude. The traditional, extended and recommended validation methods are numerically assessed on the basis of flow fields from an isolated vortex, a turbulent channel flow and a DNS simulation of forced isotropic turbulence. The resulting validation method is adaptive, requires no user-defined parameters and is demonstrated to yield the best performances in terms of outlier under- and over-detection. Finally, the novel validation routine is applied to the PIV analysis of experimental studies focused on the near wake behind a porous disc and on a supersonic jet, illustrating the potential gains in spatial resolution and accuracy.

DEVELOPMENT AND VALIDATION OF A MULTIFIELD MODEL OF CHURN-TURBULENT GAS/LIQUID FLOWS

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

Elena A. Tselishcheva; Steven P. Antal; Michael Z. Podowski

The accuracy of numerical predictions for gas/liquid two-phase flows using Computational Multiphase Fluid Dynamics (CMFD) methods strongly depends on the formulation of models governing the interaction between the continuous liquid field and bubbles of different sizes. The purpose of this paper is to develop, test and validate a multifield model of adiabatic gas/liquid flows at intermediate gas concentrations (e.g., churn-turbulent flow regime), in which multiple-size bubbles are divided into a specified number of groups, each representing a prescribed range of sizes. The proposed modeling concept uses transport equations for the continuous liquid field and for each bubble field. The overallmore » model has been implemented in the NPHASE-CMFD computer code. The results of NPHASE-CMFD simulations have been validated against the experimental data from the TOPFLOW test facility. Also, a parametric analysis on the effect of various modeling assumptions has been performed.« less

New perspectives on the dynamics of AC and DC plasma arcs exposed to cross-fields

NASA Astrophysics Data System (ADS)

Abdo, Youssef; Rohani, Vandad; Cauneau, François; Fulcheri, Laurent

2017-02-01

Interactions between an arc and external fields are crucially important for the design and the optimization of modern plasma torches. Multiple studies have been conducted to help better understand the behavior of DC and AC current arcs exposed to external and ‘self-induced’ magnetic fields, but the theoretical foundations remain very poorly explored. An analytical investigation has therefore been carried out in order to study the general behavior of DC and AC arcs under the effect of random cross-fields. A simple differential equation describing the general behavior of a planar DC or AC arc has been obtained. Several dimensionless numbers that depend primarily on arc and field parameters and the main arc characteristics (temperature, electric field strength) have also been determined. Their magnitude indicates the general tendency pattern of the arc evolution. The analytical results for many case studies have been validated using an MHD numerical model. The main purpose of this investigation was deriving a practical analytical model for the electric arc, rendering possible its stabilization and control, and the enhancement of the plasma torch power.

Comparative molecular field analysis and molecular docking studies on novel aryl chalcone derivatives against an important drug target cysteine protease in Plasmodium falciparum.

PubMed

Thillainayagam, Mahalakshmi; Anbarasu, Anand; Ramaiah, Sudha

2016-08-21

The computational studies namely molecular docking simulations and Comparative Molecular Field Analysis (CoMFA) are executed on series of 52 novel aryl chalcones derivatives using Plasmodium falciparum cysteine proteases (falcipain - 2) as vital target. In the present study, the correlation between different molecular field effects namely steric and electrostatic interactions and chemical structures to the inhibitory activities of novel aryl chalcone derivatives is inferred to perceive the major structural prerequisites for the rational design and development of potent and novel lead anti-malarial compound. The apparent binding conformations of all the compounds at the active site of falcipain - 2 and the hydrogen-bond interactions which could be used to modify the inhibitory activities are identified by using Surflex-dock study. Statistically significant CoMFA model has been developed with the cross-validated correlation coefficient (q(2)) of 0.912 and the non-cross-validated correlation coefficient (r(2)) of 0.901. Standard error of estimation (SEE) of 0.210, with the optimum number of components is ten. The predictability of the derived model is examined with a test set consists of sixteen compounds and the predicted r(2) value is found to be 0.924. The docking and QSAR study results confer crucial suggestions for the optimization of novel 1,3-diphenyl-2-propen-1-one derivatives and synthesis of effective anti- malarial compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

Violent Crime in Post-Civil War Guatemala: Causes and Policy Implications

DTIC Science & Technology

2015-03-01

on field research and case studies in Honduras, Bolivia, and Argentina. Bailey’s Security Trap theory is comprehensive in nature and derived from... research question. The second phase uses empirical data and comparative case studies to validate or challenge selected arguments that potentially...Contextual relevancy, historical inference, Tools: Empirics and case conclusions empirical data studies Figme2. Sample Research Methodology E

Interactive learning media based on flash for basic electronic engineering development for SMK Negeri 1 Driyorejo - Gresik

NASA Astrophysics Data System (ADS)

Mandigo Anggana Raras, Gustav

2018-04-01

This research aims to produce a product in the form of flash based interactive learning media on a basic electronic engineering subject that reliable to be used and to know students’ responses about the media. The target of this research is X-TEI 1 class at SMK Negeri 1 Driyorejo – Gresik. The method used in this study is R&D that has been limited into seven stages only (1) potential and problems, (2) data collection, (3) product design, (4) product validation, (5) product revision, (6) field test, and (7) analysis and writing. The obtained result is interactive learning media named MELDASH. Validation process used to produce a valid interactive learning media. The result of media validation state that the interactive learning media has a 90.83% rating. Students’ responses to this interactive learning media is really good with 88.89% rating.

Making Organisms Model Human Behavior: Situated Models in North-American Alcohol Research, 1950-onwards

PubMed Central

Leonelli, Sabina; Ankeny, Rachel A.; Nelson, Nicole C.; Ramsden, Edmund

2014-01-01

Argument We examine the criteria used to validate the use of nonhuman organisms in North-American alcohol addiction research from the 1950s to the present day. We argue that this field, where the similarities between behaviors in humans and non-humans are particularly difficult to assess, has addressed questions of model validity by transforming the situatedness of non-human organisms into an experimental tool. We demonstrate that model validity does not hinge on the standardization of one type of organism in isolation, as often the case with genetic model organisms. Rather, organisms are viewed as necessarily situated: they cannot be understood as a model for human behavior in isolation from their environmental conditions. Hence the environment itself is standardized as part of the modeling process; and model validity is assessed with reference to the environmental conditions under which organisms are studied. PMID:25233743

Validating Remotely Sensed Land Surface Evapotranspiration Based on Multi-scale Field Measurements

NASA Astrophysics Data System (ADS)

Jia, Z.; Liu, S.; Ziwei, X.; Liang, S.

2012-12-01

The land surface evapotranspiration plays an important role in the surface energy balance and the water cycle. There have been significant technical and theoretical advances in our knowledge of evapotranspiration over the past two decades. Acquisition of the temporally and spatially continuous distribution of evapotranspiration using remote sensing technology has attracted the widespread attention of researchers and managers. However, remote sensing technology still has many uncertainties coming from model mechanism, model inputs, parameterization schemes, and scaling issue in the regional estimation. Achieving remotely sensed evapotranspiration (RS_ET) with confident certainty is required but difficult. As a result, it is indispensable to develop the validation methods to quantitatively assess the accuracy and error sources of the regional RS_ET estimations. This study proposes an innovative validation method based on multi-scale evapotranspiration acquired from field measurements, with the validation results including the accuracy assessment, error source analysis, and uncertainty analysis of the validation process. It is a potentially useful approach to evaluate the accuracy and analyze the spatio-temporal properties of RS_ET at both the basin and local scales, and is appropriate to validate RS_ET in diverse resolutions at different time-scales. An independent RS_ET validation using this method was presented over the Hai River Basin, China in 2002-2009 as a case study. Validation at the basin scale showed good agreements between the 1 km annual RS_ET and the validation data such as the water balanced evapotranspiration, MODIS evapotranspiration products, precipitation, and landuse types. Validation at the local scale also had good results for monthly, daily RS_ET at 30 m and 1 km resolutions, comparing to the multi-scale evapotranspiration measurements from the EC and LAS, respectively, with the footprint model over three typical landscapes. Although some validation experiments demonstrated that the models yield accurate estimates at flux measurement sites, the question remains whether they are performing well over the broader landscape. Moreover, a large number of RS_ET products have been released in recent years. Thus, we also pay attention to the cross-validation method of RS_ET derived from multi-source models. "The Multi-scale Observation Experiment on Evapotranspiration over Heterogeneous Land Surfaces: Flux Observation Matrix" campaign is carried out at the middle reaches of the Heihe River Basin, China in 2012. Flux measurements from an observation matrix composed of 22 EC and 4 LAS are acquired to investigate the cross-validation of multi-source models over different landscapes. In this case, six remote sensing models, including the empirical statistical model, the one-source and two-source models, the Penman-Monteith equation based model, the Priestley-Taylor equation based model, and the complementary relationship based model, are used to perform an intercomparison. All the results from the two cases of RS_ET validation showed that the proposed validation methods are reasonable and feasible.

Development and Initial Validation of Perceived Competence and Satisfaction Measures for Racquet Sports.

ERIC Educational Resources Information Center

Aguilar, Teresita E.; Petrakis, Elizabeth

1989-01-01

The development and initial validation of the Racquet Sports Competence-Satisfaction Scale for measuring perceived competence and satisfaction in badminton, racquetball, and tennis is described. Results of a review panel and two field tests (with 168 and 208 university students) support the validity of the competence and satisfaction measures.…

Political homogeneity can nurture threats to research validity.

PubMed

Chambers, John R; Schlenker, Barry R

2015-01-01

Political homogeneity within a scientific field nurtures threats to the validity of many research conclusions by allowing ideologically compatible values to influence interpretations, by minimizing skepticism, and by creating premature consensus. Although validity threats can crop in any research, the usual corrective activities in science are more likely to be minimized and delayed.

Following Phaedrus: Alternate Choices in Surmounting the Reliability/Validity Dilemma

ERIC Educational Resources Information Center

Slomp, David H.; Fuite, Jim

2004-01-01

Specialists in the field of large-scale, high-stakes writing assessment have, over the last forty years alternately discussed the issue of maximizing either reliability or validity in test design. Factors complicating the debate--such as Messick's (1989) expanded definition of validity, and the ethical implications of testing--are explored. An…

Content validation of terms and definitions in a wound glossary.

PubMed

Milne, Catherine T; Paine, Tim; Sullivan, Valerie; Sawyer, Allen

2011-12-01

A common language and lexicon provide the easiest means of mutual understanding. Inconsistency in terminology makes effective information exchange difficult. Previous studies identified the need to determine standard, accepted definitions for the vocabulary frequently used in wound care. The objective of this study was to establish content validation for these terms and develop an evidence-based glossary for this specialty. Members of the Association for the Advancement of Wound Care Quality of Care Task Force reviewed literature to determine glossary content generation and the associated literature-based definitions. Thirty-nine wound care professionals from wound care stakeholder professional organizations in the United States and Canada participated in the content validation process. Participants were asked to quantify the degree of validity using a 367-item, 4-point Likert-type scale. On a scale of 1 to 4, the mean score of the entire instrument was 3.84. The instrument's overall scale content validity index was 0.96. Terms with an item content validity index of less than 0.70 were removed from the glossary, leaving 365 items with established content validity. Qualitative data analysis revealed themes suggesting that enhanced communication between providers improves patient outcomes. The need for ongoing updates of the glossary was also identified. The wound care glossary in its finalized form proved valid. An evidence-based glossary bridges the chasm of miscommunication and nonstandardization so that wound care, as an emerging specialized medical science field, can move forward to optimize both process and clinical outcomes.

Intercepting real and simulated falling objects: what is the difference?

PubMed

Baurès, Robin; Benguigui, Nicolas; Amorim, Michel-Ange; Hecht, Heiko

2009-10-30

The use of virtual reality is nowadays common in many studies in the field of human perception and movement control, particularly in interceptive actions. However, the ecological validity of the simulation is often taken for granted without having been formally established. If participants were to perceive the real situation and its virtual equivalent in a different fashion, the generalization of the results obtained in virtual reality to real life would be highly questionable. We tested the ecological validity of virtual reality in this context by comparing the timing of interceptive actions based upon actually falling objects and their simulated counterparts. The results show very limited differences as a function of whether participants were confronted with a real ball or a simulation thereof. And when present, such differences were limited to the first trial only. This result validates the use of virtual reality when studying interceptive actions of accelerated stimuli.

Revalidation of game for teaching blood pressure auscultatory measurement: a pilot study.

PubMed

Bellan, Margarete Consorti; Alves, Vanessa Cortez; Neves, Mayza Luzia Dos Santos; Lamas, José Luiz Tatagiba

2017-01-01

To adapt a pre-existing educational game, making it specific to the teaching of blood pressure auscultatory measurement, and to apply this game in a pilot study. The original game cards were altered by the authors and submitted to content validation by six experts in the field. After redesigns, the game was applied to 30 subjects, who answered a questionnaire (pre-test and post-test) on auscultatory measurement. Data were analyzed descriptively and by the paired Student's t-test and paired Wilcoxon test. Throughout the content validation process, 17 of the 28 original cards were modified. Of these 17 cards, 13 obtained 80% agreement, and the rest were modified according to the judges' suggestions. The obtained grades significantly increased between pre- and the post-test. It was concluded that the reformulated game presented satisfactory evidence of content validity. Its use as a teaching-learning method was effective for this sample.

Dynamic modelling and experimental validation of three wheeled tilting vehicles

NASA Astrophysics Data System (ADS)

Amati, Nicola; Festini, Andrea; Pelizza, Luigi; Tonoli, Andrea

2011-06-01

The present paper describes the study of the stability in the straight running of a three-wheeled tilting vehicle for urban and sub-urban mobility. The analysis was carried out by developing a multibody model in the Matlab/SimulinkSimMechanics environment. An Adams-Motorcycle model and an equivalent analytical model were developed for the cross-validation and for highlighting the similarities with the lateral dynamics of motorcycles. Field tests were carried out to validate the model and identify some critical parameters, such as the damping on the steering system. The stability analysis demonstrates that the lateral dynamic motions are characterised by vibration modes that are similar to that of a motorcycle. Additionally, it shows that the wobble mode is significantly affected by the castor trail, whereas it is only slightly affected by the dynamics of the front suspension. For the present case study, the frame compliance also has no influence on the weave and wobble.

Employee Safety Motivation: perspectives and measures on the basis of the Self-Determination theory.

PubMed

Mariani, M G; Soldà, Bianca Lara; Curcuruto, M

2015-09-09

There is a growing body of literature demonstrating that employee's safety behaviour is largely influenced by their motivation to work safely. The Self-Determination Theory, which proposes a multidimensional conceptualization of motivation, is now established in various domains of the academic field (Healthcare, Education, Psychopathology, Organizations, Sport etc.). However, there are few publications concerning its use in the analysis of motivation in a safety context, where it constitutes a new topic of study. The aim of this study was to develop and validate the Italian version of the Self-Determined Safety Motivation Scale and analyze the psychometric properties of the scale in terms of construct validity. The research involved 387 Italian employees from three companies, who occupied medium-low levels in the organizational hierarchy. A good level of psychometric properties was shown. The Italian version of the Self-Determined Safety Motivation Scale is a reliable and valid instrument to assess safety motivation.

Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study

PubMed Central

Vegh, Viktor; Reutens, David C.

2016-01-01

Object We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. Materials and Methods The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. Results A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20–50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. Conclusions A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably. PMID:27271886

Validation of Vehicle Panel/Equipment Response from Diffuse Acoustic Field Excitation Using Spatially Correlated Transfer Function Approach

NASA Technical Reports Server (NTRS)

Smith, Andrew; LaVerde, Bruce; Fulcher, Clay; Hunt, Ron

2012-01-01

An approach for predicting the vibration, strain, and force responses of a flight-like vehicle panel assembly to acoustic pressures is presented. Important validation for the approach is provided by comparison to ground test measurements in a reverberant chamber. The test article and the corresponding analytical model were assembled in several configurations to demonstrate the suitability of the approach for response predictions when the vehicle panel is integrated with equipment. Critical choices in the analysis necessary for convergence of the predicted and measured responses are illustrated through sensitivity studies. The methodology includes representation of spatial correlation of the pressure field over the panel surface. Therefore, it is possible to demonstrate the effects of hydrodynamic coincidence in the response. The sensitivity to pressure patch density clearly illustrates the onset of coincidence effects on the panel response predictions.

Two-Layer Variable Infiltration Capacity Land Surface Representation for General Circulation Models

NASA Technical Reports Server (NTRS)

Xu, L.

1994-01-01

A simple two-layer variable infiltration capacity (VIC-2L) land surface model suitable for incorporation in general circulation models (GCMs) is described. The model consists of a two-layer characterization of the soil within a GCM grid cell, and uses an aerodynamic representation of latent and sensible heat fluxes at the land surface. The effects of GCM spatial subgrid variability of soil moisture and a hydrologically realistic runoff mechanism are represented in the soil layers. The model was tested using long-term hydrologic and climatalogical data for Kings Creek, Kansas to estimate and validate the hydrological parameters. Surface flux data from three First International Satellite Land Surface Climatology Project Field Experiments (FIFE) intensive field compaigns in the summer and fall of 1987 in central Kansas, and from the Anglo-Brazilian Amazonian Climate Observation Study (ABRACOS) in Brazil were used to validate the mode-simulated surface energy fluxes and surface temperature.

A validation study of a rapid field-based rating system for discriminating among flow permanence classes of headwater streams in South Carolina

Treesearch

William Wenerick; Ken M. Fritz; Mitchell S. Kostich

2016-01-01

Classifying streams according to permanence is important in determining regulatory jurisdiction and in implementing pollution control programs. Administrators of these programs need rapid methods for making timely and defensible decisions.

The Effects of Temperature, Photoperiod, and Vernalization on Regrowth and Flowering Competence in Euphorbia Esula (Euphorbiaceae) Crown Buds

USDA-ARS?s Scientific Manuscript database

The herbaceous perennial weed Euphorbia esula (Euphorbiaceae) reproduces by vegetative and sexual means; characteristics that are key to its persistence and survival. In this study, we examined environmental effects on dormancy and flowering under controlled conditions to further validate field obse...

Active–passive soil moisture retrievals during the SMAP validation experiment 2012

USDA-ARS?s Scientific Manuscript database

The goal of this study is to assess the performance of the active–passive algorithm for the NASA Soil Moisture Active Passive mission (SMAP) using airborne and ground observations from a field campaign. The SMAP active–passive algorithm disaggregates the coarse-resolution radiometer brightness tempe...

Cross Validation of Two Partitioning-Based Sampling Approaches in Mesocosms Containing PCB Contaminated Field Sediment, Biota, and Activated Carbon Amendment

EPA Science Inventory

The Gold Standard for determining freely dissolved concentrations (Cfree) of hydrophobic organic compounds in sediment interstitial water would be in situ deployment combined with equilibrium sampling, which is generally difficult to achieve. In the present study, ex situ equilib...

Irrigation initiation timing in soybean grown on sandy soils in Northeast Arkansas

USDA-ARS?s Scientific Manuscript database

Irrigation initiation timing was evaluated in furrow-irrigated soybean field with sandy soils in Mississippi County, AR. A major objective of this 2015 study was to validate and expand irrigation timing recommendations that pair plant growth measures with weather cues including use of local weather ...

Application of a Tenax Model to Assess Bioavailability of Polychlorinated Biphenyls in Field Sediments

EPA Science Inventory

Recent literature has shown that bioavailability-based techniques, such as Tenax extraction, can estimate sediment exposure to benthos. In a previous study by the authors,Tenax extraction was used to create and validate a literature-based Tenax model to predict oligochaete bioac...

RELATIONSHIP BETWEEN DEHALOCOCCOIDES DNA IN GROUND WATER AND RATES OF REDUCTIVE DECHLORINATION AT FIELD SCALE

EPA Science Inventory

Certain strains of Dehalococcodies bacteria can dechlorinate chlorinated ethylenes to harmless products. This study was conducted to determine if there is a valid association between the amount of DNA of Dehalococcodies sp. in ground water and useful rates of dechlorination in fi...

Urban tree growth modeling

Treesearch

E. Gregory McPherson; Paula J. Peper

2012-01-01

This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...

Spaces for Learning: Development and Validation of the School Physical and Campus Environment Survey

ERIC Educational Resources Information Center

Zandvliet, David; Broekhuizen, Avril

2017-01-01

The study of learning environments involves describing educational contexts and identifying empirical relationships among subject matter (curriculum), teaching practices and other environmental variables. In recent years, this has become a growing field of academic inquiry within elementary, secondary and post-secondary research. Investigations of…

Evaluation of Resuspension from Propeller Wash in DoD Harbors

DTIC Science & Technology

2016-05-01

RESUSPENSION CHARACTERIZATION ............................................................. 11 5.3 DEEP -DRAFT RESUSPENSION STUDY IN PEARL HARBOR...RESUSPENSION FROM A DEEP -DRAFT VESSEL .............................................. 21 6.4.1 Field Observations Using ADCP...event resulted in validation of the FANS model for prediction of sediment resuspension by a deep draft vessel. While working on the resuspension

48 CFR 252.204-7004 - Alternate A, System for Award Management.

Code of Federal Regulations, 2014 CFR

2014-10-01

... validated all mandatory data fields, to include validation of the Taxpayer Identification Number (TIN) with the Internal Revenue Service (IRS). The Contractor will be required to provide consent for TIN...

48 CFR 252.204-7004 - Alternate A, System for Award Management.

Code of Federal Regulations, 2013 CFR

2013-10-01

... validated all mandatory data fields, to include validation of the Taxpayer Identification Number (TIN) with the Internal Revenue Service (IRS). The Contractor will be required to provide consent for TIN...

Pulsed plane wave analytic solutions for generic shapes and the validation of Maxwell's equations solvers

NASA Technical Reports Server (NTRS)

Yarrow, Maurice; Vastano, John A.; Lomax, Harvard

1992-01-01

Generic shapes are subjected to pulsed plane waves of arbitrary shape. The resulting scattered electromagnetic fields are determined analytically. These fields are then computed efficiently at field locations for which numerically determined EM fields are required. Of particular interest are the pulsed waveform shapes typically utilized by radar systems. The results can be used to validate the accuracy of finite difference time domain Maxwell's equations solvers. A two-dimensional solver which is second- and fourth-order accurate in space and fourth-order accurate in time is examined. Dielectric media properties are modeled by a ramping technique which simplifies the associated gridding of body shapes. The attributes of the ramping technique are evaluated by comparison with the analytic solutions.

Improved understanding of geologic CO{sub 2} storage processes requires risk-driven field experiments

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

Oldenburg, C.M.

2011-06-01

The need for risk-driven field experiments for CO{sub 2} geologic storage processes to complement ongoing pilot-scale demonstrations is discussed. These risk-driven field experiments would be aimed at understanding the circumstances under which things can go wrong with a CO{sub 2} capture and storage (CCS) project and cause it to fail, as distinguished from accomplishing this end using demonstration and industrial scale sites. Such risk-driven tests would complement risk-assessment efforts that have already been carried out by providing opportunities to validate risk models. In addition to experimenting with high-risk scenarios, these controlled field experiments could help validate monitoring approaches to improvemore » performance assessment and guide development of mitigation strategies.« less

Definition and Demonstration of a Methodology for Validating Aircraft Trajectory Predictors

NASA Technical Reports Server (NTRS)

Vivona, Robert A.; Paglione, Mike M.; Cate, Karen T.; Enea, Gabriele

2010-01-01

This paper presents a new methodology for validating an aircraft trajectory predictor, inspired by the lessons learned from a number of field trials, flight tests and simulation experiments for the development of trajectory-predictor-based automation. The methodology introduces new techniques and a new multi-staged approach to reduce the effort in identifying and resolving validation failures, avoiding the potentially large costs associated with failures during a single-stage, pass/fail approach. As a case study, the validation effort performed by the Federal Aviation Administration for its En Route Automation Modernization (ERAM) system is analyzed to illustrate the real-world applicability of this methodology. During this validation effort, ERAM initially failed to achieve six of its eight requirements associated with trajectory prediction and conflict probe. The ERAM validation issues have since been addressed, but to illustrate how the methodology could have benefited the FAA effort, additional techniques are presented that could have been used to resolve some of these issues. Using data from the ERAM validation effort, it is demonstrated that these new techniques could have identified trajectory prediction error sources that contributed to several of the unmet ERAM requirements.

Synthetic Jet Flow Field Database for CFD Validation

NASA Technical Reports Server (NTRS)

Yao, Chung-Sheng; Chen, Fang Jenq; Neuhart, Dan; Harris, Jerome

2004-01-01

An oscillatory zero net mass flow jet was generated by a cavity-pumping device, namely a synthetic jet actuator. This basic oscillating jet flow field was selected as the first of the three test cases for the Langley workshop on CFD Validation of Synthetic Jets and Turbulent Separation Control. The purpose of this workshop was to assess the current CFD capabilities to predict unsteady flow fields of synthetic jets and separation control. This paper describes the characteristics and flow field database of a synthetic jet in a quiescent fluid. In this experiment, Particle Image Velocimetry (PIV), Laser Doppler Velocimetry (LDV), and hot-wire anemometry were used to measure the jet velocity field. In addition, the actuator operating parameters including diaphragm displacement, internal cavity pressure, and internal cavity temperature were also documented to provide boundary conditions for CFD modeling.

Mean field study of a propagation-turnover lattice model for the dynamics of histone marking

NASA Astrophysics Data System (ADS)

Yao, Fan; Li, FangTing; Li, TieJun

2017-02-01

We present a mean field study of a propagation-turnover lattice model, which was proposed by Hodges and Crabtree [Proc. Nat. Acad. Sci. 109, 13296 (2012)] for understanding how posttranslational histone marks modulate gene expression in mammalian cells. The kinetics of the lattice model consists of nucleation, propagation and turnover mechanisms, and exhibits second-order phase transition for the histone marking domain. We showed rigorously that the dynamics essentially depends on a non-dimensional parameter κ = k +/ k -, the ratio between the propagation and turnover rates, which has been observed in the simulations. We then studied the lowest order mean field approximation, and observed the phase transition with an analytically obtained critical parameter. The boundary layer analysis was utilized to investigate the structure of the decay profile of the mark density. We also studied the higher order mean field approximation to achieve sharper estimate of the critical transition parameter and more detailed features. The comparison between the simulation and theoretical results shows the validity of our theory.

Numerical Investigation of Plasma Detachment in Magnetic Nozzle Experiments

NASA Technical Reports Server (NTRS)

Sankaran, Kamesh; Polzin, Kurt A.

2008-01-01

At present there exists no generally accepted theoretical model that provides a consistent physical explanation of plasma detachment from an externally-imposed magnetic nozzle. To make progress towards that end, simulation of plasma flow in the magnetic nozzle of an arcjet experiment is performed using a multidimensional numerical simulation tool that includes theoretical models of the various dispersive and dissipative processes present in the plasma. This is an extension of the simulation tool employed in previous work by Sankaran et al. The aim is to compare the computational results with various proposed magnetic nozzle detachment theories to develop an understanding of the physical mechanisms that cause detachment. An applied magnetic field topology is obtained using a magnetostatic field solver (see Fig. I), and this field is superimposed on the time-dependent magnetic field induced in the plasma to provide a self-consistent field description. The applied magnetic field and model geometry match those found in experiments by Kuriki and Okada. This geometry is modeled because there is a substantial amount of experimental data that can be compared to the computational results, allowing for validation of the model. In addition, comparison of the simulation results with the experimentally obtained plasma parameters will provide insight into the mechanisms that lead to plasma detachment, revealing how they scale with different input parameters. Further studies will focus on modeling literature experiments both for the purpose of additional code validation and to extract physical insight regarding the mechanisms driving detachment.

[Prospective multi-institutional analysis according to the "Japanese guidelines for prevention of perioperative infections in urological field"].

PubMed

Wada, Koichiro; Uehara, Shinya; Kira, Shinichiro; Matsumoto, Masahiro; Sho, Takehiko; Kurimura, Yuichiro; Hashimoto, Jiro; Uehara, Teruhisa; Yamane, Takashi; Kanamaru, Sojun; Togo, Yoshikazu; Taoka, Rikiya; Takahashi, Akira; Yamada, Yusuke; Yokomizo, Akira; Yasuda, Mitsuru; Tanaka, Kazushi; Hamasuna, Ryoichi; Takahashi, Satoshi; Hayami, Hiroshi; Watanabe, Toyohiko; Monden, Koichi; Kiyota, Hiroshi; Deguchi, Takashi; Naito, Seiji; Tsukamoto, Taiji; Arakawa, Soichi; Fujisawa, Masato; Yamamoto, Shingo; Kumon, Hiromi; Matsumoto, Tetsuro

2013-05-01

The "Japanese guidelines for prevention of perioperative infections in urological field" was edited by the Japanese Urological Association in 2007. They are the first Japanese guidelines for antimicrobial prophylaxis specifically to prevent perioperative infections in the urological field. We report here the results of a multicenter prospective study conducted to examine the validity and usefulness of these guidelines. The subjects were 513 patients who had undergone urological surgeries between July and September 2008 at 10 nationwide university institutions in the Japanese Society of UTI Cooperative Study Group. These surgeries were transurethral resection of bladder (TURBT), transurethral resection of prostate (TURP), adrenalectomy, nephrectomy, nephroureterectomy, radical prostatectomy and total cystectomy. Analysis was performed on patient information, surgical procedures, types and durations of administration of prophylactic antibiotic agents, and the presence of surgical site infections (SSI) and remote infections (RI). Of 513 patients, 387 (75.4%) were administered prophylactic antibiotic agents according to the guidelines. In these patients, the incidences of SSI and RI were 5.9% and 4.1%, respectively. Multivariate analysis showed that significant factors for SSI were the surgical risk (according to the ASA physical status classification system), diabetes, and operation time, and that the only significant factor for RI was the operation time. More large-scale study and evidences are necessary in order to demonstrate the validity and usefulness of these guidelines.

Relative brain displacement and deformation during constrained mild frontal head impact.

PubMed

Feng, Y; Abney, T M; Okamoto, R J; Pless, R B; Genin, G M; Bayly, P V

2010-12-06

This study describes the measurement of fields of relative displacement between the brain and the skull in vivo by tagged magnetic resonance imaging and digital image analysis. Motion of the brain relative to the skull occurs during normal activity, but if the head undergoes high accelerations, the resulting large and rapid deformation of neuronal and axonal tissue can lead to long-term disability or death. Mathematical modelling and computer simulation of acceleration-induced traumatic brain injury promise to illuminate the mechanisms of axonal and neuronal pathology, but numerical studies require knowledge of boundary conditions at the brain-skull interface, material properties and experimental data for validation. The current study provides a dense set of displacement measurements in the human brain during mild frontal skull impact constrained to the sagittal plane. Although head motion is dominated by translation, these data show that the brain rotates relative to the skull. For these mild events, characterized by linear decelerations near 1.5g (g = 9.81 m s⁻²) and angular accelerations of 120-140 rad s⁻², relative brain-skull displacements of 2-3 mm are typical; regions of smaller displacements reflect the tethering effects of brain-skull connections. Strain fields exhibit significant areas with maximal principal strains of 5 per cent or greater. These displacement and strain fields illuminate the skull-brain boundary conditions, and can be used to validate simulations of brain biomechanics.

Validation of the Clinical Learning Environment Inventory.

PubMed

Chan, Dominic S

2003-08-01

One hundred eight preregistration nursing students took part in this survey study, which assessed their perceptions of the clinical learning environment. Statistical data based on the sample confirmed the reliability and validity of the Clinical Learning Environment Inventory (CLEI), which was developed using the concept of classroom learning environment studies. The study also found that there were significant differences between students' actual and preferred perceptions of the clinical learning environments. In terms of the CLEI scales, students preferred a more positive and favorable clinical environment than they perceived as being actually present. The achievement of certain outcomes of clinical field placements might be enhanced by attempting to change the actual clinical environment in ways that make it more congruent with that preferred by the students.

TU-H-BRA-07: Design, Construction, and Installation of An Experimental Beam Line for the Development of MRI-Linac Compatible Electron Accelerator

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

Whelan, B; Keall, P; Holloway, L

Purpose: MRI guided radiation therapy (MRIgRT) is a rapidly growing field; however, Linac operation in MRI fringe fields represents an ongoing challenge. We have previously shown in-silico that Linacs could be redesigned to function in the in-line orientation with no magnetic shielding by adopting an RF-gun configuration. Other authors have also published insilico studies of Linac operation in magnetic fields; however to date no experimental validation data is published. This work details the design, construction, and installation of an experimental beam line to validate our in-silico results. Methods: An RF-gun comprising 1.5 accelerating cells and capable of generating electron energiesmore » up to 3.2MeV is used. The experimental apparatus was designed to monitor both beam current (toroid current monitor), spot size (two phosphor screens with viewports), and generate peak magnetic fields of at least 1000G (three variable current electromagnetic coils). Thermal FEM simulations were developed to ensure coil temperature remained within 100degC. Other design considerations included beam disposal, vacuum maintenance, radiation shielding, earthquake safety, and machine protection interlocks. Results: The beam line has been designed, built, and installed in a radiation shielded bunker. Water cooling, power supplies, thermo-couples, cameras, and radiation shielding have been successfully connected and tested. Interlock testing, vacuum processing, and RF processing have been successfully completed. The first beam on is expected within weeks. The coil heating simulations show that with care, peak fields of up to 1200G (320G at cathode) can be produced using 40A current, which is well within the fields expected for MRI-Linac systems. The maximum coil temperature at this current was 84degC after 6 minutes. Conclusion: An experimental beam line has been constructed and installed at SLAC in order to experimentally characterise RF gun performance in in-line magnetic fields, validate in-silico design work, and provide the first published experimental data relating to accelerator functionality for MRIgRT.« less

[Validity and reliability of the screening questionnaire for geriatric depression used in the Mexican Health and Age Study].

PubMed

Aguilar-Navarro, Sara Gloria; Fuentes-Cantú, Alejandro; Avila-Funes, José Alberto; García-Mayo, Emilio José

2007-01-01

To assess the validity and reliability of a geriatric depression questionnaire used in the Mexican Health and Age Study (MHAS). The study was conducted at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ) clinic from May 2005 to March 2006. This depression screening nine-item questionnaire was validated using the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) (fourth revised version) and Yesavage's 15-item Geriatric Depression Scale (GDS-15) criteria. The instrument belongs to the MHAS, a prospective panel study of health and aging in Mexico. A total of 199 subjects 65 years of age and older participated in the validation process (median age= 79.5 years). MHAS questionnaire result was significantly correlated to the clinical depression diagnosis (p<0.001) and to the GDS-15 score (p<0.001). Internal consistency was adequate (alpha coefficient: 0.74). The cutoff point > or = 5/9 points yielded an 80.7% and 68.7% sensitivity and specificity respectively. The fidelity for the test retest was excellent (intra-class correlation coefficient= 0.933). Finally, the Bland and Altman agreement points indicated a difference 0.22 percent points between test retest. The MHAS questionnaire is valid and trustworthy, and allows screening in the research field for the presence of depression in the elderly.

Towards an improved LAI collection protocol via simulated field-based PAR sensing

DOE PAGES

Yao, Wei; Van Leeuwen, Martin; Romanczyk, Paul; ...

2016-07-14

In support of NASA’s next-generation spectrometer—the Hyperspectral Infrared Imager (HyspIRI)—we are working towards assessing sub-pixel vegetation structure from imaging spectroscopy data. Of particular interest is Leaf Area Index (LAI), which is an informative, yet notoriously challenging parameter to efficiently measure in situ. While photosynthetically-active radiation (PAR) sensors have been validated for measuring crop LAI, there is limited literature on the efficacy of PAR-based LAI measurement in the forest environment. This study (i) validates PAR-based LAI measurement in forest environments, and (ii) proposes a suitable collection protocol, which balances efficiency with measurement variation, e.g., due to sun flecks and various-sized canopymore » gaps. A synthetic PAR sensor model was developed in the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model and used to validate LAI measurement based on first-principles and explicitly-known leaf geometry. Simulated collection parameters were adjusted to empirically identify optimal collection protocols. Furthermore, these collection protocols were then validated in the field by correlating PAR-based LAI measurement to the normalized difference vegetation index (NDVI) extracted from the “classic” Airborne Visible Infrared Imaging Spectrometer (AVIRIS-C) data (R 2 was 0.61). The results indicate that our proposed collecting protocol is suitable for measuring the LAI of sparse forest (LAI < 3–5 ( m 2/m 2)).« less

Validation and optimization of SST k-ω turbulence model for pollutant dispersion within a building array

NASA Astrophysics Data System (ADS)

Yu, Hesheng; Thé, Jesse

2016-11-01

The prediction of the dispersion of air pollutants in urban areas is of great importance to public health, homeland security, and environmental protection. Computational Fluid Dynamics (CFD) emerges as an effective tool for pollutant dispersion modelling. This paper reports and quantitatively validates the shear stress transport (SST) k-ω turbulence closure model and its transitional variant for pollutant dispersion under complex urban environment for the first time. Sensitivity analysis is performed to establish recommendation for the proper use of turbulence models in urban settings. The current SST k-ω simulation is validated rigorously by extensive experimental data using hit rate for velocity components, and the "factor of two" of observations (FAC2) and fractional bias (FB) for concentration field. The simulation results show that current SST k-ω model can predict flow field nicely with an overall hit rate of 0.870, and concentration dispersion with FAC2 = 0.721 and FB = 0.045. The flow simulation of the current SST k-ω model is slightly inferior to that of a detached eddy simulation (DES), but better than that of standard k-ε model. However, the current study is the best among these three model approaches, when validated against measurements of pollutant dispersion in the atmosphere. This work aims to provide recommendation for proper use of CFD to predict pollutant dispersion in urban environment.

R1 dispersion contrast at high field with fast field-cycling MRI.

PubMed

Bödenler, Markus; Basini, Martina; Casula, Maria Francesca; Umut, Evrim; Gösweiner, Christian; Petrovic, Andreas; Kruk, Danuta; Scharfetter, Hermann

2018-05-01

Contrast agents with a strong R 1 dispersion have been shown to be effective in generating target-specific contrast in MRI. The utilization of this R 1 field dependence requires the adaptation of an MRI scanner for fast field-cycling (FFC). Here, we present the first implementation and validation of FFC-MRI at a clinical field strength of 3 T. A field-cycling range of ±100 mT around the nominal B 0 field was realized by inserting an additional insert coil into an otherwise conventional MRI system. System validation was successfully performed with selected iron oxide magnetic nanoparticles and comparison to FFC-NMR relaxometry measurements. Furthermore, we show proof-of-principle R 1 dispersion imaging and demonstrate the capability of generating R 1 dispersion contrast at high field with suppressed background signal. With the presented ready-to-use hardware setup it is possible to investigate MRI contrast agents with a strong R 1 dispersion at a field strength of 3 T. Copyright © 2018 Elsevier Inc. All rights reserved.

Butterfly Floquet Spectrum in Driven SU(2) Systems

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

Wang Jiao; Department of Physics, Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005; Gong Jiangbin

2009-06-19

The Floquet spectrum of a class of driven SU(2) systems is shown to display a butterfly pattern with multifractal properties. The level crossing between Floquet states of the same parity or different parities is studied. The results are relevant to studies of fractal statistics, quantum chaos, coherent destruction of tunneling, and the validity of mean-field descriptions of Bose-Einstein condensates.

Parenting Practices Scale: Its Validity and Reliability for Parents of School-Aged Children

ERIC Educational Resources Information Center

Kahraman, Hanife; Yilmaz Irmak, Turkan; Basokcu, T. Oguz

2017-01-01

Parenting practices are a field in psychology in which numerous studies have been carried out. In western countries, attempts to define the concept operationally have led to the emergence of many scales claiming to test the concept. This study aims at developing a scale to evaluate the parenting practices of parents with schoolchildren and at…

A Pedagogical Trebuchet: A Case Study in Experimental History and History Pedagogy

ERIC Educational Resources Information Center

Brice, Lee L.; Catania, Steven

2012-01-01

A common problem history teachers face regardless of their field of specialization is how to help students find answers to the most difficult historical questions, those for which the sources are unavailable or inaccessible, and teach them to do so in a methodologically valid manner. This article presents a case study which shows how a project in…

Modelling the Dynamics of Bodies Self-Propelled by Exponential Mass Exhaustion

ERIC Educational Resources Information Center

Rodrigues, Hilario; Pinho, Marcos Oliveira; Portes, Dirceu, Jr.; Santiago, Arnaldo Jose

2008-01-01

We present a study of the ascending vertical motion of a self-propelled body under a uniform gravitational field suffering the action of two different types of air friction forces: linear on the velocity, which is valid for slowly moving bodies, and quadratic on the velocity. We study the special case where the thrust force is a decreasing…

Structural Validity of the Polish Adaptation of the Picture-Based Value Survey for Children (PBVS-C)

ERIC Educational Resources Information Center

Cieciuch, Jan; Harasimczuk, Justyna; Doring, Anna K.

2013-01-01

Recent years have witnessed an increasing number of studies, also in the field of educational psychology, on values within the framework proposed by Schwartz, involving younger and younger respondents. A fresh impetus to studies on children's values was given by the Picture-Based Value Survey for Children (PBVS-C), which was developed by Doring…

Rice crop growth monitoring using ENVISAT-1/ASAR AP mode

NASA Astrophysics Data System (ADS)

Konishi, Tomohisa; Suga, Yuzo; Omatu, Shigeru; Takeuchi, Shoji; Asonuma, Kazuyoshi

2007-10-01

Hiroshima Institute of Technology (HIT) is operating the direct down-links of microwave and optical earth observation satellite data in Japan. This study focuses on the validation for rice crop monitoring using microwave remotely sensed image data acquired by ENIVISAT-1 referring to ground truth data such as height of rice crop, vegetation cover rate and leaf area index in the test sites of Hiroshima district, the western part of Japan. ENVISAT-1/ASAR data has the capabilities for the monitoring of the rice crop growing cycle by using alternating cross polarization mode images. However, ASAR data is influenced by several parameters such as land cover structure, direction and alignment of rice crop fields in the test sites. In this study, the validation was carried out to be combined with microwave image data and ground truth data regarding rice crop fields to investigate the above parameters. Multi-temporal, multi-direction (descending and ascending) and multi-angle ASAR alternating cross polarization mode images were used to investigate during the rice crop growing cycle. On the other hand, LANDSAT-7/ETM+ data were used to detect land cover structure, direction and alignment of rice crop fields corresponding to the backscatter of ASAR. Finally, the extraction of rice planted area was attempted by using multi-temporal ASAR AP mode data such as VV/VH and HH/HV. As the result of this study, it is clear that the estimated rice planted area coincides with the existing statistical data for area of the rice crop field. In addition, HH/HV is more effective than VV/VH in the rice planted area extraction.

A revised surface resistance parameterisation for estimating latent heat flux from remotely sensed data

NASA Astrophysics Data System (ADS)

Song, Yi; Wang, Jiemin; Yang, Kun; Ma, Mingguo; Li, Xin; Zhang, Zhihui; Wang, Xufeng

2012-07-01

Estimating evapotranspiration (ET) is required for many environmental studies. Remote sensing provides the ability to spatially map latent heat flux. Many studies have developed approaches to derive spatially distributed surface energy fluxes from various satellite sensors with the help of field observations. In this study, remote-sensing-based λE mapping was conducted using a Landsat Thematic Mapper (TM) image and an Enhanced Thematic Mapper Plus (ETM+) image. The remotely sensed data and field observations employed in this study were obtained from Watershed Allied Telemetry Experimental Research (WATER). A biophysics-based surface resistance model was revised to account for water stress and temperature constraints. The precision of the results was validated using 'ground truth' data obtained by eddy covariance (EC) system. Scale effects play an important role, especially for parameter optimisation and validation of the latent heat flux (λE). After considering the footprint of EC, the λE derived from the remote sensing data was comparable to the EC measured value during the satellite's passage. The results showed that the revised surface resistance parameterisation scheme was useful for estimating the latent heat flux over cropland in arid regions.

Validation of an in-vivo proton beam range check method in an anthropomorphic pelvic phantom using dose measurements

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

Bentefour, El H., E-mail: hassan.bentefour@iba-group.com; Prieels, Damien; Tang, Shikui

Purpose: In-vivo dosimetry and beam range verification in proton therapy could play significant role in proton treatment validation and improvements. In-vivo beam range verification, in particular, could enable new treatment techniques one of which could be the use of anterior fields for prostate treatment instead of opposed lateral fields as in current practice. This paper reports validation study of an in-vivo range verification method which can reduce the range uncertainty to submillimeter levels and potentially allow for in-vivo dosimetry. Methods: An anthropomorphic pelvic phantom is used to validate the clinical potential of the time-resolved dose method for range verification inmore » the case of prostrate treatment using range modulated anterior proton beams. The method uses a 3 × 4 matrix of 1 mm diodes mounted in water balloon which are read by an ADC system at 100 kHz. The method is first validated against beam range measurements by dose extinction measurements. The validation is first completed in water phantom and then in pelvic phantom for both open field and treatment field configurations. Later, the beam range results are compared with the water equivalent path length (WEPL) values computed from the treatment planning system XIO. Results: Beam range measurements from both time-resolved dose method and the dose extinction method agree with submillimeter precision in water phantom. For the pelvic phantom, when discarding two of the diodes that show sign of significant range mixing, the two methods agree with ±1 mm. Only a dose of 7 mGy is sufficient to achieve this result. The comparison to the computed WEPL by the treatment planning system (XIO) shows that XIO underestimates the protons beam range. Quantifying the exact XIO range underestimation depends on the strategy used to evaluate the WEPL results. To our best evaluation, XIO underestimates the treatment beam range between a minimum of 1.7% and maximum of 4.1%. Conclusions: Time-resolved dose measurement method satisfies the two basic requirements, WEPL accuracy and minimum dose, necessary for clinical use, thus, its potential for in-vivo protons range verification. Further development is needed, namely, devising a workflow that takes into account the limits imposed by proton range mixing and the susceptibility of the comparison of measured and expected WEPLs to errors on the detector positions. The methods may also be used for in-vivo dosimetry and could benefit various proton therapy treatments.« less

The instruments of higher order thinking skills

NASA Astrophysics Data System (ADS)

Ahmad, S.; Prahmana, R. C. I.; Kenedi, A. K.; Helsa, Y.; Arianil, Y.; Zainil, M.

2017-12-01

This research developed the standard of instrument for measuring the High Order Thinking Skill (HOTS) ability of PGSD students. The research method used is development research with eight steps namely theoretical studies, operational definition, designation construct, dimensions and indicators, the preparation of the lattice, the preparation of grain, an analysis of legibility and Social desirability, field trials, and data analysis. In accordance with the type of data to be obtained in this study, the research instrument using validation sheet, implementation observation, and questionnaire. The results show that the instruments are valid and feasible to be used by expert and have been tested on PGSD students with 60% of PGSD students with low categorization.

FAST Model Calibration and Validation of the OC5-DeepCwind Floating Offshore Wind System Against Wave Tank Test Data

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

Wendt, Fabian F; Robertson, Amy N; Jonkman, Jason

During the course of the Offshore Code Comparison Collaboration, Continued, with Correlation (OC5) project, which focused on the validation of numerical methods through comparison against tank test data, the authors created a numerical FAST model of the 1:50-scale DeepCwind semisubmersible system that was tested at the Maritime Research Institute Netherlands ocean basin in 2013. This paper discusses several model calibration studies that were conducted to identify model adjustments that improve the agreement between the numerical simulations and the experimental test data. These calibration studies cover wind-field-specific parameters (coherence, turbulence), hydrodynamic and aerodynamic modeling approaches, as well as rotor model (blade-pitchmore » and blade-mass imbalances) and tower model (structural tower damping coefficient) adjustments. These calibration studies were conducted based on relatively simple calibration load cases (wave only/wind only). The agreement between the final FAST model and experimental measurements is then assessed based on more-complex combined wind and wave validation cases.« less

Evidence-based medicine for every day, everyone, and every therapeutic study.

PubMed

Govindarajan, Raghav; Narayanaswami, Pushpa

2018-04-17

The rapid growth in published medical literature makes it difficult for clinicians to keep up with advances in their fields. This may result in a cursory scan of the abstract and conclusion of a study without critically evaluating study quality. The application of evidence-based medicine (EBM) is the process of converting the abstract task of reading the literature into a practical method of using the literature to inform care in a specific clinical context while simultaneously expanding one's knowledge. EBM involves 4 steps: (1) stating the clinical problem in a defined question; (2) searching the literature for the evidence; (3) critically appraising the evidence for its validity; and (4) applying the evidence in the context of the patient's situation, preferences, and values. In this review, we use the recently published trial of thymectomy in myasthenia gravis as an example and systematically go through the steps of assessing internal validity, precision, and external validity. Muscle Nerve, 2018. © 2018 Wiley Periodicals, Inc.

Low-cost extrapolation method for maximal LTE radio base station exposure estimation: test and validation.

PubMed

Verloock, Leen; Joseph, Wout; Gati, Azeddine; Varsier, Nadège; Flach, Björn; Wiart, Joe; Martens, Luc

2013-06-01

An experimental validation of a low-cost method for extrapolation and estimation of the maximal electromagnetic-field exposure from long-term evolution (LTE) radio base station installations are presented. No knowledge on downlink band occupation or service characteristics is required for the low-cost method. The method is applicable in situ. It only requires a basic spectrum analyser with appropriate field probes without the need of expensive dedicated LTE decoders. The method is validated both in laboratory and in situ, for a single-input single-output antenna LTE system and a 2×2 multiple-input multiple-output system, with low deviations in comparison with signals measured using dedicated LTE decoders.

High-fidelity Simulation of Jet Noise from Rectangular Nozzles . [Large Eddy Simulation (LES) Model for Noise Reduction in Advanced Jet Engines and Automobiles

NASA Technical Reports Server (NTRS)

Sinha, Neeraj

2014-01-01

This Phase II project validated a state-of-the-art LES model, coupled with a Ffowcs Williams-Hawkings (FW-H) far-field acoustic solver, to support the development of advanced engine concepts. These concepts include innovative flow control strategies to attenuate jet noise emissions. The end-to-end LES/ FW-H noise prediction model was demonstrated and validated by applying it to rectangular nozzle designs with a high aspect ratio. The model also was validated against acoustic and flow-field data from a realistic jet-pylon experiment, thereby significantly advancing the state of the art for LES.

Developing Online Course Portal to Improve Teachers’ Competency in Creating Action Research (CAR) Proposal Using Learning Management System (LMS) Moodle

NASA Astrophysics Data System (ADS)

Muhtar, A. A.

2017-02-01

Online course can offer flexible and easy way to improve teachers’ competency in conducting education research, especially in classroom action research (CAR). Teachers can attend the course without physically present in the class. This research aims to (1) develop online course portal to improve teachers’ competency in creating CAR proposal, and (2) produce proper online course portal validated and evaluated from four aspects: learning process, content, graphic user interface and programming. Online course in this research developed using Learning Management System (LMS) Moodle. The research model is using modified Borg & Gall Research and Development (R&D) started from preliminary studies, designing product, creating product, and evaluation. Product validated by three experts from three universities. Research subjects for field test are seven teachers as participants from different schools in several provinces in Indonesia. Based on expert validation and field test results, the product developed in this research categorized as “very good” in all aspects and it is suitable for teacher to improve their competency in creating CAR proposal. Online course portal produced in this research can be used as a proper model for online learning in creating CAR proposal.

Smoothed particle hydrodynamic modeling of volcanic debris flows: Application to Huiloac Gorge lahars (Popocatépetl volcano, Mexico)

NASA Astrophysics Data System (ADS)

Haddad, Bouchra; Palacios, David; Pastor, Manuel; Zamorano, José Juan

2016-09-01

Lahars are among the most catastrophic volcanic processes, and the ability to model them is central to mitigating their effects. Several lahars recently generated by the Popocatépetl volcano (Mexico) moved downstream through the Huiloac Gorge towards the village of Santiago Xalitzintla. The most dangerous was the 2001 lahar, in which the destructive power of the debris flow was maintained throughout the extent of the flow. Identifying the zone of hazard can be based either on numerical or empirical models, but a calibration and validation process is required to ensure hazard map quality. The Geoflow-SPH depth integrated numerical model used in this study to reproduce the 2001 lahar was derived from the velocity-pressure version of the Biot-Zienkiewicz model, and was discretized using the smoothed particle hydrodynamics (SPH) method. The results of the calibrated SPH model were validated by comparing the simulated deposit depth with the field depth measured at 16 cross sections distributed strategically along the gorge channel. Moreover, the dependency of the results on topographic mesh resolution, initial lahar mass shape and dimensions is also investigated. The results indicate that to accurately reproduce the 2001 lahar flow dynamics the channel topography needed to be discretized using a mesh having a minimum 5 m resolution, and an initial lahar mass shape that adopted the source area morphology. Field validation of the calibrated model showed that there was a satisfactory relationship between the simulated and field depths, the error being less than 20% for 11 of the 16 cross sections. This study demonstrates that the Geoflow-SPH model was able to accurately reproduce the lahar path and the extent of the flow, but also reproduced other parameters including flow velocity and deposit depth.

EGFR Overexpressed in Colonic Neoplasia Can be Detected on Wide-Field Endoscopic Imaging.

PubMed

Zhou, Juan; Joshi, Bishnu P; Duan, Xiyu; Pant, Asha; Qiu, Zhen; Kuick, Rork; Owens, Scott R; Wang, Thomas D

2015-07-16

Colorectal cancer initially lies dormant as dysplasia, a premalignant state that provides an opportunity for early cancer detection. Dysplasia can be flat in morphology, focal in size, and patchy in distribution, and thus it appears "invisible" on conventional wide-field endoscopy. We aim to develop and validate a peptide that is specific for epidermal growth factor receptor (EGFR), a cell surface target that is overexpressed in colonic adenomas and is readily accessible for imaging. We expressed and purified the extracellular domain of EGFR for use with phage display to identify a peptide QRHKPRE that binds to domain 2 of this target. A near-infrared fluorescence endoscope was used to perform in vivo imaging to validate specific peptide binding to spontaneous colonic adenomas in a mouse model with topical administration. We also validated specific peptide binding to human colonic adenomas on immunohistochemistry and immunofluorescence. After labeling with Cy5.5, we validated specific peptide binding to EGFR on knockdown and competition studies. Peptide binding to cells occurred within 2.46 min and had an affinity of 50 nm. No downstream signaling was observed. We measured a target-to-background ratio of 4.0±1.7 and 2.7±0.7, for polyps and flat lesions, respectively. On immunofluorescence of human colonic specimens, greater intensity from peptide binding to dysplasia than normal was found with a 19.4-fold difference. We have selected and validated a peptide that can be used as a specific contrast agent to identify colonic adenomas that overexpress EGFR in vivo on fluorescence endoscopy.

An analytical computation of magnetic field generated from a cylinder ferromagnet

NASA Astrophysics Data System (ADS)

Taniguchi, Tomohiro

2018-04-01

An analytical formulation to compute a magnetic field generated from an uniformly magnetized cylinder ferromagnet is developed. Exact solutions of the magnetic field generated from the magnetization pointing in an arbitrary direction are derived, which are applicable both inside and outside the ferromagnet. The validities of the present formulas are confirmed by comparing them with demagnetization coefficients estimated in earlier works. The results will be useful for designing practical applications, such as high-density magnetic recording and microwave generators, where nanostructured ferromagnets are coupled to each other through the dipole interactions and show cooperative phenomena such as synchronization. As an example, the magnetic field generated from a spin torque oscillator for magnetic recording based on microwave assisted magnetization reversal is studied.

Validating a driving simulator using surrogate safety measures.

PubMed

Yan, Xuedong; Abdel-Aty, Mohamed; Radwan, Essam; Wang, Xuesong; Chilakapati, Praveen

2008-01-01

Traffic crash statistics and previous research have shown an increased risk of traffic crashes at signalized intersections. How to diagnose safety problems and develop effective countermeasures to reduce crash rate at intersections is a key task for traffic engineers and researchers. This study aims at investigating whether the driving simulator can be used as a valid tool to assess traffic safety at signalized intersections. In support of the research objective, this simulator validity study was conducted from two perspectives, a traffic parameter (speed) and a safety parameter (crash history). A signalized intersection with as many important features (including roadway geometries, traffic control devices, intersection surroundings, and buildings) was replicated into a high-fidelity driving simulator. A driving simulator experiment with eight scenarios at the intersection were conducted to determine if the subjects' speed behavior and traffic risk patterns in the driving simulator were similar to what were found at the real intersection. The experiment results showed that speed data observed from the field and in the simulator experiment both follow normal distributions and have equal means for each intersection approach, which validated the driving simulator in absolute terms. Furthermore, this study used an innovative approach of using surrogate safety measures from the simulator to contrast with the crash analysis for the field data. The simulator experiment results indicated that compared to the right-turn lane with the low rear-end crash history record (2 crashes), subjects showed a series of more risky behaviors at the right-turn lane with the high rear-end crash history record (16 crashes), including higher deceleration rate (1.80+/-1.20 m/s(2) versus 0.80+/-0.65 m/s(2)), higher non-stop right-turn rate on red (81.67% versus 57.63%), higher right-turn speed as stop line (18.38+/-8.90 km/h versus 14.68+/-6.04 km/h), shorter following distance (30.19+/-13.43 m versus 35.58+/-13.41 m), and higher rear-end probability (9/59=0.153 versus 2/60=0.033). Therefore, the relative validity of driving simulator was well established for the traffic safety studies at signalized intersections.

Measurements and simulation of forest leaf area index and net primary productivity in Northern China.

PubMed

Wang, P; Sun, R; Hu, J; Zhu, Q; Zhou, Y; Li, L; Chen, J M

2007-11-01

Large scale process-based modeling is a useful approach to estimate distributions of global net primary productivity (NPP). In this paper, in order to validate an existing NPP model with observed data at site level, field experiments were conducted at three sites in northern China. One site is located in Qilian Mountain in Gansu Province, and the other two sites are in Changbaishan Natural Reserve and Dunhua County in Jilin Province. Detailed field experiments are discussed and field data are used to validate the simulated NPP. Remotely sensed images including Landsat Enhanced Thematic Mapper plus (ETM+, 30 m spatial resolution in visible and near infrared bands) and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER, 15m spatial resolution in visible and near infrared bands) are used to derive maps of land cover, leaf area index, and biomass. Based on these maps, field measured data, soil texture and daily meteorological data, NPP of these sites are simulated for year 2001 with the boreal ecosystem productivity simulator (BEPS). The NPP in these sites ranges from 80 to 800 gCm(-2)a(-1). The observed NPP agrees well with the modeled NPP. This study suggests that BEPS can be used to estimate NPP in northern China if remotely sensed images of high spatial resolution are available.

Estimating salinity stress in sugarcane fields with spaceborne hyperspectral vegetation indices

NASA Astrophysics Data System (ADS)

Hamzeh, S.; Naseri, A. A.; AlaviPanah, S. K.; Mojaradi, B.; Bartholomeus, H. M.; Clevers, J. G. P. W.; Behzad, M.

2013-04-01

The presence of salt in the soil profile negatively affects the growth and development of vegetation. As a result, the spectral reflectance of vegetation canopies varies for different salinity levels. This research was conducted to (1) investigate the capability of satellite-based hyperspectral vegetation indices (VIs) for estimating soil salinity in agricultural fields, (2) evaluate the performance of 21 existing VIs and (3) develop new VIs based on a combination of wavelengths sensitive for multiple stresses and find the best one for estimating soil salinity. For this purpose a Hyperion image of September 2, 2010, and data on soil salinity at 108 locations in sugarcane (Saccharum officina L.) fields were used. Results show that soil salinity could well be estimated by some of these VIs. Indices related to chlorophyll absorption bands or based on a combination of chlorophyll and water absorption bands had the highest correlation with soil salinity. In contrast, indices that are only based on water absorption bands had low to medium correlations, while indices that use only visible bands did not perform well. From the investigated indices the optimized soil-adjusted vegetation index (OSAVI) had the strongest relationship (R2 = 0.69) with soil salinity for the training data, but it did not perform well in the validation phase. The validation procedure showed that the new salinity and water stress indices (SWSI) implemented in this study (SWSI-1, SWSI-2, SWSI-3) and the Vogelmann red edge index yielded the best results for estimating soil salinity for independent fields with root mean square errors of 1.14, 1.15, 1.17 and 1.15 dS/m, respectively. Our results show that soil salinity could be estimated by satellite-based hyperspectral VIs, but validation of obtained models for independent data is essential for selecting the best model.

Tilt Current Meter Field Validation in the Surf Zone

NASA Astrophysics Data System (ADS)

Anarde, K.; Myres, H.; Figlus, J.

2016-12-01

Tilt current meters (TCMs) are a low-cost way of measuring current velocities in coastal waters. They consist of a slightly buoyant floater, tilt sensor assembly, and internal logger tethered to a fixed base. TCMs measure the tilt of the sensor induced by the forces of the flowing water to infer local current velocity. They have been successfully deployed to measure unidirectional flows in rivers and slowly oscillating flows in tidally influenced bodies of water where the inertia of the instrument does not create a problem. Here we attempt to validate an array of TCMs for use in the surf zone where waves, wave bores, and alongshore currents dominate the hydrodynamics in relatively shallow water (0.3 - 2.0 m) with relatively high oscillatory frequencies. A series of test deployments using seven measuring pods outfitted with TCMs and pressure transducers were conducted in the surf zone off Galveston Island, Texas. Field experiments were supported by laboratory tests of the instrument assemblies in a moveable-bed wave flume. Instrument pod design was optimized over the series of tests to minimize issues caused by scouring, sedimentation, and overturning. The end design consists of a low-profile concrete base plate secured to the bed by sand stakes. Field measurements of tilt and bearing were calibrated against co-located acoustic Doppler velocimeter (ADV) and wave-current profiler (ADCP) measurements as well as laboratory-supplied calibration curves. While optimization of the setup is ongoing, the initial field studies show good correlation between instrument pairs. If successfully validated, the TCMs will be used as part of an instrument array designed to measure overland flow dynamics during extreme storms. Other potential uses include detailed analysis of spatial and temporal gradients in nearshore hydrodynamics such as the complex flow scenarios through tidal inlets and around barrier islands.

A multicenter prospective cohort study on camera navigation training for key user groups in minimally invasive surgery.

PubMed

Graafland, Maurits; Bok, Kiki; Schreuder, Henk W R; Schijven, Marlies P

2014-06-01

Untrained laparoscopic camera assistants in minimally invasive surgery (MIS) may cause suboptimal view of the operating field, thereby increasing risk for errors. Camera navigation is often performed by the least experienced member of the operating team, such as inexperienced surgical residents, operating room nurses, and medical students. The operating room nurses and medical students are currently not included as key user groups in structured laparoscopic training programs. A new virtual reality laparoscopic camera navigation (LCN) module was specifically developed for these key user groups. This multicenter prospective cohort study assesses face validity and construct validity of the LCN module on the Simendo virtual reality simulator. Face validity was assessed through a questionnaire on resemblance to reality and perceived usability of the instrument among experts and trainees. Construct validity was assessed by comparing scores of groups with different levels of experience on outcome parameters of speed and movement proficiency. The results obtained show uniform and positive evaluation of the LCN module among expert users and trainees, signifying face validity. Experts and intermediate experience groups performed significantly better in task time and camera stability during three repetitions, compared to the less experienced user groups (P < .007). Comparison of learning curves showed significant improvement of proficiency in time and camera stability for all groups during three repetitions (P < .007). The results of this study show face validity and construct validity of the LCN module. The module is suitable for use in training curricula for operating room nurses and novice surgical trainees, aimed at improving team performance in minimally invasive surgery. © The Author(s) 2013.

Towards policy relevant environmental modeling: contextual validity and pragmatic models

USGS Publications Warehouse

Miles, Scott B.

2000-01-01

"What makes for a good model?" In various forms, this question is a question that, undoubtedly, many people, businesses, and institutions ponder with regards to their particular domain of modeling. One particular domain that is wrestling with this question is the multidisciplinary field of environmental modeling. Examples of environmental models range from models of contaminated ground water flow to the economic impact of natural disasters, such as earthquakes. One of the distinguishing claims of the field is the relevancy of environmental modeling to policy and environment-related decision-making in general. A pervasive view by both scientists and decision-makers is that a "good" model is one that is an accurate predictor. Thus, determining whether a model is "accurate" or "correct" is done by comparing model output to empirical observations. The expected outcome of this process, usually referred to as "validation" or "ground truthing," is a stamp on the model in question of "valid" or "not valid" that serves to indicate whether or not the model will be reliable before it is put into service in a decision-making context. In this paper, I begin by elaborating on the prevailing view of model validation and why this view must change. Drawing from concepts coming out of the studies of science and technology, I go on to propose a contextual view of validity that can overcome the problems associated with "ground truthing" models as an indicator of model goodness. The problem of how we talk about and determine model validity has much to do about how we perceive the utility of environmental models. In the remainder of the paper, I argue that we should adopt ideas of pragmatism in judging what makes for a good model and, in turn, developing good models. From such a perspective of model goodness, good environmental models should facilitate communication, convey—not bury or "eliminate"—uncertainties, and, thus, afford the active building of consensus decisions, instead of promoting passive or self-righteous decisions.

Field Validation of the Stability Limit of a Multi MW Turbine

NASA Astrophysics Data System (ADS)

Kallesøe, Bjarne S.; Kragh, Knud A.

2016-09-01

Long slender blades of modern multi-megawatt turbines exhibit a flutter like instability at rotor speeds above a critical rotor speed. Knowing the critical rotor speed is crucial to a safe turbine design. The flutter like instability can only be estimated using geometrically non-linear aeroelastic codes. In this study, the estimated rotor speed stability limit of a 7 MW state of the art wind turbine is validated experimentally. The stability limit is estimated using Siemens Wind Powers in-house aeroelastic code, and the results show that the predicted stability limit is within 5% of the experimentally observed limit.

ACCESS - A Science and Engineering Assessment of Space Coronagraph Concepts for the Direct Imaging and Spectroscopy of Exoplanetary Systems

NASA Technical Reports Server (NTRS)

Trauger, John

2008-01-01

Topics include and overview, science objectives, study objectives, coronagraph types, metrics, ACCESS observatory, laboratory validations, and summary. Individual slides examine ACCESS engineering approach, ACCESS gamut of coronagraph types, coronagraph metrics, ACCESS Discovery Space, coronagraph optical layout, wavefront control on the "level playing field", deformable mirror development for HCIT, laboratory testbed demonstrations, high contract imaging with the HCIT, laboratory coronagraph contrast and stability, model validation and performance predictions, HCIT coronagraph optical layout, Lyot coronagraph on the HCIT, pupil mapping (PIAA), shaped pupils, and vortex phase mask experiments on the HCIT.

An optimization model to agroindustrial sector in antioquia (Colombia, South America)

NASA Astrophysics Data System (ADS)

Fernandez, J.

2015-06-01

This paper develops a proposal of a general optimization model for the flower industry, which is defined by using discrete simulation and nonlinear optimization, whose mathematical models have been solved by using ProModel simulation tools and Gams optimization. It defines the operations that constitute the production and marketing of the sector, statistically validated data taken directly from each operation through field work, the discrete simulation model of the operations and the linear optimization model of the entire industry chain are raised. The model is solved with the tools described above and presents the results validated in a case study.

Development and validation of a computer-based situational judgement test to assess medical students' communication skills in the field of shared decision making.

PubMed

Kiessling, Claudia; Bauer, Johannes; Gartmeier, Martin; Iblher, Peter; Karsten, Gudrun; Kiesewetter, Jan; Moeller, Grit E; Wiesbeck, Anne; Zupanic, Michaela; Fischer, Martin R

2016-11-01

To develop a computer-based test (CBT) measuring medical students' communication skills in the field of shared decision making (SDM) and to evaluate its construct validity. The CBT was developed in the context of an experimental study comparing three different trainings for SDM (including e-learning and/or role-play) and a control group. Assessment included a CBT (Part A: seven context-poor questions, Part B: 15 context-rich questions) and interviews with two simulated patients (SP-assessment). Cronbach's α was used to test the internal consistency. Correlations between CBT and SP-assessment were used to further evaluate construct validity of the CBT. Seventy-two students took part in the study. Mean value for the CBT score was 72% of the total score. Cronbach's α was 0.582. After eliminating three items, Cronbach's α increased to 0.625. Correlations between the CBT and SP-assessment were low to moderate. The control group scored significantly lower than the training settings (p<0.001). The CBT was reliable enough to test for group differences. For summative assessment purposes, considerably more questions would be needed. We encourage teachers who particularly work with large student numbers to consider CBT as a feasible assessment method for cognitive aspects of communication skills. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An investigation into possible quantum chaos in the H2 molecule under intense laser fields via Ehrenfest phase space (EPS) trajectories.

PubMed

Sadhukhan, Mainak; Deb, B M

2018-06-21

By employing the Ehrenfest "phase space" trajectory method for studying quantum chaos, developed in our laboratory, the present study reveals that the H 2 molecule under intense laser fields of three different intensities, I = 1 × 10 14  W/cm 2 , 5 × 10 14  W/cm 2 , and 1 × 10 15  W/cm 2 , does not show quantum chaos. A similar conclusion is also reached through the Loschmidt echo (also called quantum fidelity) calculations reported here for the first time for a real molecule under intense laser fields. Thus, a long-standing conjecture about the possible existence of quantum chaos in atoms and molecules under intense laser fields has finally been tested and not found to be valid in the present case.

Emission of fermions in little string theory

NASA Astrophysics Data System (ADS)

Lorente-Espín, Oscar

2013-03-01

It is well known that little string theory (LST) black holes radiate a purely thermal spectrum of scalar particles. This theory lives in a Hagedorn phase with a fixed Hagedorn temperature that does not depend on its mass. Therefore, the theory keeps a thermal profile even taking into account self-gravitating effects and the backreaction of the metric. This has implications concerning the information loss paradox; one would not be able to recover any information from the LST black hole since the emission of scalar particles is totally uncorrelated. Several studies of the emission spectrum in LST concern scalar fields; it is our aim in this work to extend the study to the emission of fermions in order to verify that the most relevant conclusion for the scalar field remains valid for the fermion fields. Thus, we have calculated the emission probability, the flux, and also the greybody factor corresponding to a fermion field in LST background.

Improved Force Fields for Peptide Nucleic Acids with Optimized Backbone Torsion Parameters.

PubMed

Jasiński, Maciej; Feig, Michael; Trylska, Joanna

2018-06-06

Peptide nucleic acids are promising nucleic acid analogs for antisense therapies as they can form stable duplex and triplex structures with DNA and RNA. Computational studies of PNA-containing duplexes and triplexes are an important component for guiding their design, yet existing force fields have not been well validated and parametrized with modern computational capabilities. We present updated CHARMM and Amber force fields for PNA that greatly improve the stability of simulated PNA-containing duplexes and triplexes in comparison with experimental structures and allow such systems to be studied on microsecond time scales. The force field modifications focus on reparametrized PNA backbone torsion angles to match high-level quantum mechanics reference energies for a model compound. The microsecond simulations of PNA-PNA, PNA-DNA, PNA-RNA, and PNA-DNA-PNA complexes also allowed a comprehensive analysis of hydration and ion interactions with such systems.

Scalar transport in inline mixers with spatially periodic flows

NASA Astrophysics Data System (ADS)

Baskan, Ozge; Rajaei, Hadi; Speetjens, Michel F. M.; Clercx, Herman J. H.

2017-01-01

Spatially persisting patterns form during the downstream evolution of passive scalars in three-dimensional (3D) spatially periodic flows due to the coupled effect of stretching and folding mechanisms of the flow field. This has been investigated in many computational and theoretical studies of 2D time-periodic and 3D spatially periodic flow fields. However, experimental studies, to date, have mainly focused on flow visualization with streaks of dye rather than fully 3D scalar field measurements. Our study employs 3D particle tracking velocimetry and 3D laser-induced fluorescence to analyze the evolution of 3D flow and scalar fields and the correlation between the coherent flow/scalar field structures in a representative inline mixer, the Quatro static mixer. For this purpose an experimental setup that consists of an optically accessible test section with transparent internal elements accommodating a pressure-driven pipe flow has been built. The flow and scalar fields clearly underline the complementarity of the experimental results with numerical simulations and provide validation of the periodicity assumption needed in numerical studies. The experimental procedure employed in this investigation, which allows studying the scalar transport in the advective limit, demonstrates the suitability of the present method for exploratory mixing studies of a variety of mixing devices, beyond the Quatro static mixer.

Experimental validation of plastic constitutive hardening relationship based upon the direction of the Net Burgers Density Vector

NASA Astrophysics Data System (ADS)

Sarac, Abdulhamit; Kysar, Jeffrey W.

2018-02-01

We present a new methodology for experimental validation of single crystal plasticity constitutive relationships based upon spatially resolved measurements of the direction of the Net Burgers Density Vector, which we refer to as the β-field. The β-variable contains information about the active slip systems as well as the ratios of the Geometrically Necessary Dislocation (GND) densities on the active slip systems. We demonstrate the methodology by comparing single crystal plasticity finite element simulations of plane strain wedge indentations into face-centered cubic nickel to detailed experimental measurements of the β-field. We employ the classical Peirce-Asaro-Needleman (PAN) hardening model in this study due to the straightforward physical interpretation of its constitutive parameters that include latent hardening ratio, initial hardening modulus and the saturation stress. The saturation stress and the initial hardening modulus have relatively large influence on the β-variable compared to the latent hardening ratio. A change in the initial hardening modulus leads to a shift in the boundaries of plastic slip sectors with the plastically deforming region. As the saturation strength varies, both the magnitude of the β-variable and the boundaries of the plastic slip sectors change. We thus demonstrate that the β-variable is sensitive to changes in the constitutive parameters making the variable suitable for validation purposes. We identify a set of constitutive parameters that are consistent with the β-field obtained from the experiment.

Validation of the DIFFAL, HPAC and HotSpot Dispersion Models Using the Full-Scale Radiological Dispersal Device (FSRDD) Field Trials Witness Plate Deposition Dataset.

PubMed

Purves, Murray; Parkes, David

2016-05-01

Three atmospheric dispersion models--DIFFAL, HPAC, and HotSpot--of differing complexities have been validated against the witness plate deposition dataset taken during the Full-Scale Radiological Dispersal Device (FSRDD) Field Trials. The small-scale nature of these trials in comparison to many other historical radiological dispersion trials provides a unique opportunity to evaluate the near-field performance of the models considered. This paper performs validation of these models using two graphical methods of comparison: deposition contour plots and hotline profile graphs. All of the models tested are assessed to perform well, especially considering that previous model developments and validations have been focused on larger-scale scenarios. Of the models, HPAC generally produced the most accurate results, especially at locations within ∼100 m of GZ. Features present within the observed data, such as hot spots, were not well modeled by any of the codes considered. Additionally, it was found that an increase in the complexity of the meteorological data input to the models did not necessarily lead to an improvement in model accuracy; this is potentially due to the small-scale nature of the trials.

Aeroacoustic Validation of Installed Low Noise Propulsion for NASA's N+2 Supersonic Airliner

NASA Technical Reports Server (NTRS)

Bridges, James

2018-01-01

An aeroacoustic test was conducted at NASA Glenn Research Center on an integrated propulsion system designed to meet noise regulations of ICAO Chapter 4 with 10EPNdB cumulative margin. The test had two objectives: to demonstrate that the aircraft design did meet the noise goal, and to validate the acoustic design tools used in the design. Variations in the propulsion system design and its installation were tested and the results compared against predictions. Far-field arrays of microphones measured the acoustic spectral directivity, which was transformed to full scale as noise certification levels. Phased array measurements confirmed that the shielding of the installation model adequately simulated the full aircraft and provided data for validating RANS-based noise prediction tools. Particle image velocimetry confirmed that the flow field around the nozzle on the jet rig mimicked that of the full aircraft and produced flow data to validate the RANS solutions used in the noise predictions. The far-field acoustic measurements confirmed the empirical predictions for the noise. Results provided here detail the steps taken to ensure accuracy of the measurements and give insights into the physics of exhaust noise from installed propulsion systems in future supersonic vehicles.

Modeling, implementation, and validation of arterial travel time reliability.

DOT National Transportation Integrated Search

2013-11-01

Previous research funded by Florida Department of Transportation (FDOT) developed a method for estimating : travel time reliability for arterials. This method was not initially implemented or validated using field data. This : project evaluated and r...

Implications of Using the GAD Hypothesis in Paleopole Studies for the Moon

NASA Astrophysics Data System (ADS)

Powell, J.; Stanley, S.

2017-12-01

The Moon does not currently have a dynamo-generated magnetic field, however, observations of crustal magnetism and paleomagnetic analyses of Apollo samples have demonstrated that the Moon did possess a dynamo-generated field in the past. Several studies have attempted to use magnetic paleopole analyses to determine the previous rotation poles of the Moon and thereby infer lunar true polar wander. However, these studies all assumed that the Geocentric Axial Dipole (GAD) hypothesis is valid for the Moon. In this study we perform a paleopole analysis of dynamo simulations relevant to the ancient Moon to show the biases inherent in assuming the GAD hypothesis for the Moon. The results of this research have implications for studies of lunar true polar wander.

Development and validation of a novel large field of view phantom and a software module for the quality assurance of geometric distortion in magnetic resonance imaging.

PubMed

Torfeh, Tarraf; Hammoud, Rabih; McGarry, Maeve; Al-Hammadi, Noora; Perkins, Gregory

2015-09-01

To develop and validate a large field of view phantom and quality assurance software tool for the assessment and characterization of geometric distortion in MRI scanners commissioned for radiation therapy planning. A purpose built phantom was developed consisting of 357 rods (6mm in diameter) of polymethyl-methacrylat separated by 20mm intervals, providing a three dimensional array of control points at known spatial locations covering a large field of view up to a diameter of 420mm. An in-house software module was developed to allow automatic geometric distortion assessment. This software module was validated against a virtual dataset of the phantom that reproduced the exact geometry of the physical phantom, but with known translational and rotational displacements and warping. For validation experiments, clinical MRI sequences were acquired with and without the application of a commercial 3D distortion correction algorithm (Gradwarp™). The software module was used to characterize and assess system-related geometric distortion in the sequences relative to a benchmark CT dataset, and the efficacy of the vendor geometric distortion correction algorithms (GDC) was also assessed. Results issued from the validation of the software against virtual images demonstrate the algorithm's ability to accurately calculate geometric distortion with sub-pixel precision by the extraction of rods and quantization of displacements. Geometric distortion was assessed for the typical sequences used in radiotherapy applications and over a clinically relevant 420mm field of view (FOV). As expected and towards the edges of the field of view (FOV), distortion increased with increasing FOV. For all assessed sequences, the vendor GDC was able to reduce the mean distortion to below 1mm over a field of view of 5, 10, 15 and 20cm radius respectively. Results issued from the application of the developed phantoms and algorithms demonstrate a high level of precision. The results indicate that this platform represents an important, robust and objective tool to perform routine quality assurance of MR-guided therapeutic applications, where spatial accuracy is paramount. Copyright © 2015 Elsevier Inc. All rights reserved.

Translating Behavioral Science into Practice: A Framework to Determine Science Quality and Applicability for Police Organizations.

PubMed

McClure, Kimberley A; McGuire, Katherine L; Chapan, Denis M

2018-05-07

Policy on officer-involved shootings is critically reviewed and errors in applying scientific knowledge identified. Identifying and evaluating the most relevant science to a field-based problem is challenging. Law enforcement administrators with a clear understanding of valid science and application are in a better position to utilize scientific knowledge for the benefit of their organizations and officers. A recommended framework is proposed for considering the validity of science and its application. Valid science emerges via hypothesis testing, replication, extension and marked by peer review, known error rates, and general acceptance in its field of origin. Valid application of behavioral science requires an understanding of the methodology employed, measures used, and participants recruited to determine whether the science is ready for application. Fostering a science-practitioner partnership and an organizational culture that embraces quality, empirically based policy, and practices improves science-to-practice translation. © 2018 American Academy of Forensic Sciences.

Validity of the Catapult ClearSky T6 Local Positioning System for Team Sports Specific Drills, in Indoor Conditions

PubMed Central

Luteberget, Live S.; Spencer, Matt; Gilgien, Matthias

2018-01-01

Aim: The aim of the present study was to determine the validity of position, distance traveled and instantaneous speed of team sport players as measured by a commercially available local positioning system (LPS) during indoor use. In addition, the study investigated how the placement of the field of play relative to the anchor nodes and walls of the building affected the validity of the system. Method: The LPS (Catapult ClearSky T6, Catapult Sports, Australia) and the reference system [Qualisys Oqus, Qualisys AB, Sweden, (infra-red camera system)] were installed around the field of play to capture the athletes' motion. Athletes completed five tasks, all designed to imitate team-sports movements. The same protocol was completed in two sessions, one with an assumed optimal geometrical setup of the LPS (optimal condition), and once with a sub-optimal geometrical setup of the LPS (sub-optimal condition). Raw two-dimensional position data were extracted from both the LPS and the reference system for accuracy assessment. Position, distance and speed were compared. Results: The mean difference between the LPS and reference system for all position estimations was 0.21 ± 0.13 m (n = 30,166) in the optimal setup, and 1.79 ± 7.61 m (n = 22,799) in the sub-optimal setup. The average difference in distance was below 2% for all tasks in the optimal condition, while it was below 30% in the sub-optimal condition. Instantaneous speed showed the largest differences between the LPS and reference system of all variables, both in the optimal (≥35%) and sub-optimal condition (≥74%). The differences between the LPS and reference system in instantaneous speed were speed dependent, showing increased differences with increasing speed. Discussion: Measures of position, distance, and average speed from the LPS show low errors, and can be used confidently in time-motion analyses for indoor team sports. The calculation of instantaneous speed from LPS raw data is not valid. To enhance instantaneous speed calculation the application of appropriate filtering techniques to enhance the validity of such data should be investigated. For all measures, the placement of anchor nodes and the field of play relative to the walls of the building influence LPS output to a large degree. PMID:29670530

Validation of the ultrasonographic assessment of the femoral trochlea epiphyseal cartilage in foals at osteochondrosis predilected sites with magnetic resonance imaging and histology.

PubMed

Martel, G; Forget, C; Gilbert, G; Richard, H; Moser, T; Olive, J; Laverty, S

2017-11-01

Noninvasive imaging tools are needed to screen foal femoropatellar joints to detect subclinical osteochondrosis lesions due to focal failure of endochondral ossification to enhance early management to optimise intrinsic healing events. Recently investigations employing 3T susceptibility-weighted magnetic resonance imaging (3T SWI MRI) and CT have demonstrated their capacity for early osteochondrosis diagnosis, but these technologies are not practical for field screening. We postulate that ultrasonography is a valuable field tool for the detection of subclinical osteochondrosis lesions. The goals were to 1) describe the ultrasonographic features of the femoral trochlea of healthy and osteochondrosis-predisposed neonatal foals, 2) validate the capacity of ultrasound to assess cartilage canal vascular archictecture and the ossification front and 3) evaluate field feasibility in a pilot study. Experimental study. Ultrasonographic evaluation of osteochondrosis predisposed (n = 10) and control (n = 6) femoral trochleas was performed ex vivo and compared with site-matched histological sections and 3T SWI MRI. The articular and epiphyseal cartilage thickness, ossification front indentation and cartilage canal vascular archictecture were assessed at each ROI. Femoral trochleae of foals (n = 3) aged ≈ 1, 3 and 6 months were also evaluated with ultrasonography in field. Ultrasonographic measurements strongly correlated with the histological measurements. There was no difference in the cartilage thickness or ossification front indentation between control and osteochondrosis-predisposed specimens. The cartilage canal vascular archictecture on ultrasonograms corresponded with the vessel pattern observed on site matched histology and 3T SWI MRI. The number of specimens for study was limited and no early osteochondrosis lesions were present within the predilected group, but a field study is now underway. Ultrasonographic examination of the femoral trochlea permitted accurate evaluation of cartilage thickness, cartilage canal vascular archictecture and ossification front indentation in young foals and is a promising, practical tool for screening subclinical osteochondrosis and monitoring and managing lesions at important clinical sites. © 2017 EVJ Ltd.

Impact of GNSS orbit modeling on LEO orbit and gravity field determination

NASA Astrophysics Data System (ADS)

Arnold, Daniel; Meyer, Ulrich; Sušnik, Andreja; Dach, Rolf; Jäggi, Adrian

2017-04-01

On January 4, 2015 the Center for Orbit Determination in Europe (CODE) changed the solar radiation pressure modeling for GNSS satellites to an updated version of the empirical CODE orbit model (ECOM). Furthermore, since September 2012 CODE operationally computes satellite clock corrections not only for the 3-day long-arc solutions, but also for the non-overlapping 1-day GNSS orbits. This provides different sets of GNSS products for Precise Point Positioning, as employed, e.g., in the GNSS-based precise orbit determination of low Earth orbiters (LEOs) and the subsequent Earth gravity field recovery from kinematic LEO orbits. While the impact of the mentioned changes in orbit modeling and solution strategy on the GNSS orbits and geophysical parameters was studied in detail, their implications on the LEO orbits were not yet analyzed. We discuss the impact of the update of the ECOM and the influence of 1-day and 3-day GNSS orbit solutions on zero-difference LEO orbit and gravity field determination, where the GNSS orbits and clock corrections, as well as the Earth rotation parameters are introduced as fixed external products. Several years of kinematic and reduced-dynamic orbits for the two GRACE LEOs are computed with GNSS products based on both the old and the updated ECOM, as well as with 1- and 3-day GNSS products. The GRACE orbits are compared by means of standard validation measures. Furthermore, monthly and long-term GPS-only and combined GPS/K-band gravity field solutions are derived from the different sets of kinematic LEO orbits. GPS-only fields are validated by comparison to combined GPS/K-band solutions, while the combined solutions are validated by analysis of the formal errors, as well as by comparing them to the combined GRACE solutions of the European Gravity Service for Improved Emergency Management (EGSIEM) project.

Validity and reliability of bioelectrical impedance analysis and skinfold thickness in predicting body fat in military personnel.

PubMed

Aandstad, Anders; Holtberget, Kristian; Hageberg, Rune; Holme, Ingar; Anderssen, Sigmund A

2014-02-01

Previous studies show that body composition is related to injury risk and physical performance in soldiers. Thus, valid methods for measuring body composition in military personnel are needed. The frequently used body mass index method is not a valid measure of body composition in soldiers, but reliability and validity of alternative field methods are less investigated in military personnel. Thus, we carried out test and retest of skinfold (SKF), single frequency bioelectrical impedance analysis (SF-BIA), and multifrequency bioelectrical impedance analysis measurements in 65 male and female soldiers. Several validated equations were used to predict percent body fat from these methods. Dual-energy X-ray absorptiometry was also measured, and acted as the criterion method. Results showed that SF-BIA was the most reliable method in both genders. In women, SF-BIA was also the most valid method, whereas SKF or a combination of SKF and SF-BIA produced the highest validity in men. Reliability and validity varied substantially among the equations examined. The best methods and equations produced test-retest 95% limits of agreement below ±1% points, whereas the corresponding validity figures were ±3.5% points. Each investigator and practitioner must consider whether such measurement errors are acceptable for its specific use. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

A non-invasive assessment of skin carotenoid status through reflection spectroscopy is a feasible, reliable and potentially valid measure of fruit and vegetable consumption in a diverse community sample.

PubMed

Jilcott Pitts, Stephanie Bell; Jahns, Lisa; Wu, Qiang; Moran, Nancy E; Bell, Ronny A; Truesdale, Kimberly P; Laska, Melissa N

2018-06-01

To assess the feasibility, reliability and validity of reflection spectroscopy (RS) to assess skin carotenoids in a racially diverse sample. Study 1 was a cross-sectional study of corner store customers (n 479) who completed the National Cancer Institute Fruit and Vegetable Screener as well as RS measures. Feasibility was assessed by examining the time it took to complete three RS measures, reliability was assessed by examining the variation between three RS measures, and validity was examined by correlation with self-reported fruit and vegetable consumption. In Study 2, validity was assessed in a smaller sample (n 30) by examining associations between RS measures and dietary carotenoids, fruits and vegetables as calculated from a validated FFQ and plasma carotenoids. Eastern North Carolina, USA. It took on average 94·0 s to complete three RS readings per person. The average variation between three readings for each participant was 6·8 %. In Study 2, in models adjusted for age, race and sex, there were statistically significant associations between RS measures and (i) FFQ-estimated carotenoid intake (P<0·0001); (ii) FFQ-estimated fruit and vegetable consumption (P<0·010); and (iii) plasma carotenoids (P<0·0001). RS is a potentially improved method to approximate fruit and vegetable consumption among diverse participants. RS is portable and easy to use in field-based public health nutrition settings. More research is needed to investigate validity and sensitivity in diverse populations.

Particles with nonlinear electric response: Suppressing van der Waals forces by an external field.

PubMed

Soo, Heino; Dean, David S; Krüger, Matthias

2017-01-01

We study the classical thermal component of Casimir, or van der Waals, forces between point particles with highly anharmonic dipole Hamiltonians when they are subjected to an external electric field. Using a model for which the individual dipole moments saturate in a strong field (a model that mimics the charges in a neutral, perfectly conducting sphere), we find that the resulting Casimir force depends strongly on the strength of the field, as demonstrated by analytical results. For a certain angle between the external field and center-to-center axis, the fluctuation force can be tuned and suppressed to arbitrarily small values. We compare the forces between these particles with those between particles with harmonic Hamiltonians and also provide a simple formula for asymptotically large external fields, which we expect to be generally valid for the case of saturating dipole moments.

Transcranial magnetic stimulation of mouse brain using high-resolution anatomical models

NASA Astrophysics Data System (ADS)

Crowther, L. J.; Hadimani, R. L.; Kanthasamy, A. G.; Jiles, D. C.

2014-05-01

Transcranial magnetic stimulation (TMS) offers the possibility of non-invasive treatment of brain disorders in humans. Studies on animals can allow rapid progress of the research including exploring a variety of different treatment conditions. Numerical calculations using animal models are needed to help design suitable TMS coils for use in animal experiments, in particular, to estimate the electric field induced in animal brains. In this paper, we have implemented a high-resolution anatomical MRI-derived mouse model consisting of 50 tissue types to accurately calculate induced electric field in the mouse brain. Magnetic field measurements have been performed on the surface of the coil and compared with the calculations in order to validate the calculated magnetic and induced electric fields in the brain. Results show how the induced electric field is distributed in a mouse brain and allow investigation of how this could be improved for TMS studies using mice. The findings have important implications in further preclinical development of TMS for treatment of human diseases.

Synchronization Design and Error Analysis of Near-Infrared Cameras in Surgical Navigation.

PubMed

Cai, Ken; Yang, Rongqian; Chen, Huazhou; Huang, Yizhou; Wen, Xiaoyan; Huang, Wenhua; Ou, Shanxing

2016-01-01

The accuracy of optical tracking systems is important to scientists. With the improvements reported in this regard, such systems have been applied to an increasing number of operations. To enhance the accuracy of these systems further and to reduce the effect of synchronization and visual field errors, this study introduces a field-programmable gate array (FPGA)-based synchronization control method, a method for measuring synchronous errors, and an error distribution map in field of view. Synchronization control maximizes the parallel processing capability of FPGA, and synchronous error measurement can effectively detect the errors caused by synchronization in an optical tracking system. The distribution of positioning errors can be detected in field of view through the aforementioned error distribution map. Therefore, doctors can perform surgeries in areas with few positioning errors, and the accuracy of optical tracking systems is considerably improved. The system is analyzed and validated in this study through experiments that involve the proposed methods, which can eliminate positioning errors attributed to asynchronous cameras and different fields of view.

Experimental simulation of the effects of sudden increases in geomagnetic activity upon quantitative measures of human brain activity: validation of correlational studies.

PubMed

Mulligan, Bryce P; Persinger, Michael A

2012-05-10

Previous correlations between geomagnetic activity and quantitative changes in electroencephalographic power revealed particular associations with the right parietal lobe for theta activity and the right frontal region for gamma activity. In the present experiment subjects were exposed to either no field (sham conditions) or to either 20 nT or 70 nT, 7 Hz, amplitude modulated (mHz range) magnetic fields for 30 min. Quantitative electroencephalographic (QEEG) measurements were completed before, during, and after the field exposures. After about 10 min of exposure theta power over the right parietal region was enhanced for the 20 nT exposure but suppressed for the 70 nT exposure relative to sham field exposures. The effect dissipated by the end of the exposure. These results support the contention that magnetic field fluctuations were primarily responsible for the significant geomagnetic-QEEG correlations reported in several studies. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

[Reliability and validity of the Braden Scale for predicting pressure sore risk].

PubMed

Boes, C

2000-12-01

For more accurate and objective pressure sore risk assessment various risk assessment tools were developed mainly in the USA and Great Britain. The Braden Scale for Predicting Pressure Sore Risk is one such example. By means of a literature analysis of German and English texts referring to the Braden Scale the scientific control criteria reliability and validity will be traced and consequences for application of the scale in Germany will be demonstrated. Analysis of 4 reliability studies shows an exclusive focus on interrater reliability. Further, even though examination of 19 validity studies occurs in many different settings, such examination is limited to the criteria sensitivity and specificity (accuracy). The range of sensitivity and specificity level is 35-100%. The recommended cut off points rank in the field of 10 to 19 points. The studies prove to be not comparable with each other. Furthermore, distortions in these studies can be found which affect accuracy of the scale. The results of the here presented analysis show an insufficient proof for reliability and validity in the American studies. In Germany, the Braden scale has not yet been tested under scientific criteria. Such testing is needed before using the scale in different German settings. During the course of such testing, construction and study procedures of the American studies can be used as a basis as can the problems be identified in the analysis presented below.

Radiative transfer model validations during the First ISLSCP Field Experiment

NASA Technical Reports Server (NTRS)

Frouin, Robert; Breon, Francois-Marie; Gautier, Catherine

1990-01-01

Two simple radiative transfer models, the 5S model based on Tanre et al. (1985, 1986) and the wide-band model of Morcrette (1984) are validated by comparing their outputs with results obtained during the First ISLSCP Field Experiment on concomitant radiosonde, aerosol turbidity, and radiation measurements and sky photographs. Results showed that the 5S model overestimates the short-wave irradiance by 13.2 W/sq m, whereas the Morcrette model underestimated the long-wave irradiance by 7.4 W/sq m.

Validation on the mechanical models of asphalt pavement structures with field measured data associated with increasing freight movements.

DOT National Transportation Integrated Search

2012-10-05

This study is aimed at better understanding the effects of heavy trucks on the performance of asphalt pavements. As the U.S. freight movements are dominated by truck transportations, the addition of new roadway lane-miles in Region VII have not kept ...

The Relation between Distance Education Students' Motivation and Satisfaction

ERIC Educational Resources Information Center

Goulimaris, Dimitrios

2015-01-01

The aim of the present study, within the frame of self-determination theory (SDT), was triple: a) to examine the structural validity of the "Situational Motivation Scale" (SIMS) in the field of distance education, b) to investigate the correlation between the subscales of the motivation and satisfaction of students who attend distance…

Comparisons of Conceptual Preference for Cultural and Leadership Behavior in an Information Technology Organization

ERIC Educational Resources Information Center

Valley, Amina B.

2009-01-01

The primary focus of the research study conducted was to analyze the predictive leadership behaviors of Southern Asian and United States individuals in the information technology career field. This research validates the leadership traits and behaviors of information technology types of United States individuals that enhance the impact of…

Incorporating Nonparametric Statistics into Delphi Studies in Library and Information Science

ERIC Educational Resources Information Center

Ju, Boryung; Jin, Tao

2013-01-01

Introduction: The Delphi technique is widely used in library and information science research. However, many researchers in the field fail to employ standard statistical tests when using this technique. This makes the technique vulnerable to criticisms of its reliability and validity. The general goal of this article is to explore how…

Cognitive Complexity in the Remote Association Test--Chinese Version

ERIC Educational Resources Information Center

Hung, Su-Pin; Huang, Po-Sheng; Chen, Hsueh-Chih

2016-01-01

The remote association test (RAT) has been applied in various fields; however, evidence of construct validity for the original version and subsequent extensions of the RAT remains limited. This study aimed to elucidate the dimensionality and the relationship between item features and item difficulties for the RAT--Chinese Version (RAT-C) using the…

Assessment of Leisure Preferences for Students with Severe Developmental Disabilities and Communication Difficulties

ERIC Educational Resources Information Center

Kreiner, Janice; Flexer, Robert

2009-01-01

The purpose of this study was to develop and to evaluate the Preferences for Leisure Attributes (PLA) Assessment, a forced-choice computer software program for students with severe disabilities and communication difficulties. In order to determine content validity of the PLA Assessment, four experts in related fields assigned critical attributes…

Survey of candidate genes for maize resistance to infection by Aspergillus flavus and/or aflatoxin contamination

Treesearch

Leigh Hawkins; Marilyn Warburton; Juliet Tang; John Tomashek; Dafne Alves Oliveira; Oluwaseun Ogunola; J. Smith; W. Williams

2018-01-01

Many projects have identified candidate genes for resistance to aflatoxin accumulation or Aspergillus flavus infection and growth in maize using genetic mapping, genomics, transcriptomics and/or proteomics studies. However, only a small percentage of these candidates have been validated in field conditions, and their relative contribution to...

Tracking Holland Interest Codes: The Case of South African Field Guides

ERIC Educational Resources Information Center

Watson, Mark B.; Foxcroft, Cheryl D.; Allen, Lynda J.

2007-01-01

Holland believes that specific personality types seek out matching occupational environments and his theory codes personality and environment according to a six letter interest typology. Since 1985 there have been numerous American studies that have queried the validity of Holland's coding system. Research in South Africa is scarcer, despite…

Competition, Anxiety, and Depression in the College Classroom: Variations by Student Identity and Field of Study

ERIC Educational Resources Information Center

Posselt, Julie R.; Lipson, Sarah Ketchen

2016-01-01

In light of rising academic stress and an increase in diagnosed mental illnesses among adolescents and young adults, this article offers the first comprehensive analysis of relationships between perceived competition and depression/anxiety among college students. Analyses were conducted by using clinically validated instruments for depression and…

How Teachers Become Leaders: An Internationally Validated Theoretical Model of Teacher Leadership Development

ERIC Educational Resources Information Center

Poekert, Philip; Alexandrou, Alex; Shannon, Darbianne

2016-01-01

Teacher leadership is increasingly being touted as a practical response to guide teacher learning in school improvement and policy reform efforts. However, the field of research on teacher leadership in relation to post-compulsory educational development has been and remains largely atheoretical to date. This empirical study proposes a grounded…

Measuring the Quality of Inclusive Practices: Findings from the Inclusive Classroom Profile Pilot

ERIC Educational Resources Information Center

Soukakou, Elena P.; Winton, Pam J.; West, Tracey A.; Sideris, John H.; Rucker, Lia M.

2014-01-01

The purpose of this study was to test the reliability and validity of the Inclusive Classroom Profile (ICP), an observation measure designed to assess the quality of classroom practices in inclusive preschool programs. The measure was field tested in 51 inclusive classrooms. Results confirmed and extended previous research findings, providing…

3D-QSAR studies of some reversible Acetyl cholinesterase inhibitors based on CoMFA and ligand protein interaction fingerprints using PC-LS-SVM and PLS-LS-SVM.

PubMed

Ghafouri, Hamidreza; Ranjbar, Mohsen; Sakhteman, Amirhossein

2017-08-01

A great challenge in medicinal chemistry is to develop different methods for structural design based on the pattern of the previously synthesized compounds. In this study two different QSAR methods were established and compared for a series of piperidine acetylcholinesterase inhibitors. In one novel approach, PC-LS-SVM and PLS-LS-SVM was used for modeling 3D interaction descriptors, and in the other method the same nonlinear techniques were used to build QSAR equations based on field descriptors. Different validation methods were used to evaluate the models and the results revealed the more applicability and predictive ability of the model generated by field descriptors (Q 2 LOO-CV =1, R 2 ext =0.97). External validation criteria revealed that both methods can be used in generating reasonable QSAR models. It was concluded that due to ability of interaction descriptors in prediction of binding mode, using this approach can be implemented in future 3D-QSAR softwares. Copyright © 2017 Elsevier Ltd. All rights reserved.

Clinical proteomic biomarkers: relevant issues on study design & technical considerations in biomarker development

PubMed Central

2014-01-01

Biomarker research is continuously expanding in the field of clinical proteomics. A combination of different proteomic–based methodologies can be applied depending on the specific clinical context of use. Moreover, current advancements in proteomic analytical platforms are leading to an expansion of biomarker candidates that can be identified. Specifically, mass spectrometric techniques could provide highly valuable tools for biomarker research. Ideally, these advances could provide with biomarkers that are clinically applicable for disease diagnosis and/ or prognosis. Unfortunately, in general the biomarker candidates fail to be implemented in clinical decision making. To improve on this current situation, a well-defined study design has to be established driven by a clear clinical need, while several checkpoints between the different phases of discovery, verification and validation have to be passed in order to increase the probability of establishing valid biomarkers. In this review, we summarize the technical proteomic platforms that are available along the different stages in the biomarker discovery pipeline, exemplified by clinical applications in the field of bladder cancer biomarker research. PMID:24679154

Psychometric Validation of the Academic Motivation Scale in a Dental Student Sample.

PubMed

Orsini, Cesar; Binnie, Vivian; Evans, Phillip; Ledezma, Priscilla; Fuentes, Fernando; Villegas, Maria J

2015-08-01

The Academic Motivation Scale is one of the most frequently used instruments to assess academic motivation. It relies on the self-determination theory of human motivation. However, motivation has been understudied in dental education. Therefore, to address the lack of valid instruments to assess academic motivation in dental education and contribute to future research in the field, the aim of this study was to analyze the psychometric properties of this instrument in a sample of dental students. Participants were 989 Chilean undergraduate dental students (86% response rate) who completed a survey containing a Chilean face-valid version of the Spanish Academic Motivation Scale and three other motivation-related instruments to assess the survey's construct and criterion validity. Later, 76 of the students (out of 100 invited) took the survey again to assess its test-retest stability. The instrument's construct validity was supported by the superior goodness of fit of the seven-subscale Academic Motivation Scale over competing models through confirmatory factor analysis and by the expected correlations among its subscales. The concurrent criterion validity was supported by the confirmation of correlations between its subscales and external criteria. Adequate internal consistency and test-retest correlations were also found. The evidence from this study suggests that the Academic Motivation Scale is a preliminarily valid and reliable instrument to assess motivation in the predoctoral dental context. Future research in this area is needed to confirm or refute these results.

A recursive field-normalized bibliometric performance indicator: an application to the field of library and information science.

PubMed

Waltman, Ludo; Yan, Erjia; van Eck, Nees Jan

2011-10-01

Two commonly used ideas in the development of citation-based research performance indicators are the idea of normalizing citation counts based on a field classification scheme and the idea of recursive citation weighing (like in PageRank-inspired indicators). We combine these two ideas in a single indicator, referred to as the recursive mean normalized citation score indicator, and we study the validity of this indicator. Our empirical analysis shows that the proposed indicator is highly sensitive to the field classification scheme that is used. The indicator also has a strong tendency to reinforce biases caused by the classification scheme. Based on these observations, we advise against the use of indicators in which the idea of normalization based on a field classification scheme and the idea of recursive citation weighing are combined.

Chiral magnetic effect in the presence of electroweak interactions as a quasiclassical phenomenon

NASA Astrophysics Data System (ADS)

Dvornikov, Maxim; Semikoz, Victor B.

2018-03-01

We elaborate the quasiclassical approach to obtain the modified chiral magnetic effect (CME) in the case when the massless charged fermions interact with electromagnetic fields and the background matter by the electroweak forces. The derivation of the anomalous current along the external magnetic field involves the study of the energy density evolution of chiral particles in parallel electric and magnetic fields. We consider both the particle acceleration by the external electric field and the contribution of the Adler anomaly. The condition of the validity of this method for the derivation of the CME is formulated. We obtain the expression for the electric current along the external magnetic field, which appears to coincide with our previous results based on the purely quantum approach. Our results are compared with the findings of other authors.