Science.gov

Sample records for measuring prior environment

  1. Inducing multipartite entanglement revival in dissipative environment by means of prior quantum uncollapsing measurements

    NASA Astrophysics Data System (ADS)

    He, Juan; Xu, Shuai; Ye, Liu

    2015-11-01

    A scheme for inducing multipartite entanglement revival in the dissipative environment is proposed, which is implemented by performing a prior quantum uncollapsing (weak measurements or measurement reversals) procedure on partial qubits of the system simultaneously. This procedure preferentially equips our initial states, and make them hold more powerful ability to actively battle against degradation of entanglement, even postpone entanglement sudden death (ESD). Notably, the effect is more pronounced for the multipartite system with less initial entanglement. In addition, we found that our scheme also works for the N-qubit GHZ-class state.

  2. Prior mapping for nonlinear flows in random environments.

    PubMed

    Tartakovsky, D M; Guadagnini, A

    2001-09-01

    We analyze nonlinear flows in randomly heterogeneous environments, which are characterized by state-dependent diffusion coefficients with spatially correlated structures. The prior Kirchhoff mapping is used to describe such systems by linear stochastic partial differential equations with multiplicative noise. These are solved through moment equations which are closed, alternatively, either by perturbation expansions, or by a posterior linear mapping closure. The latter relies on the assumption that the state variable is a spatially distributed Gaussian field. We demonstrate that the former approach is more robust. PMID:11580383

  3. Adjusting capitation rates using objective health measures and prior utilization

    PubMed Central

    Newhouse, Joseph P.; Manning, Willard G.; Keeler, Emmett B.; Sloss, Elizabeth M.

    1989-01-01

    Several analysts have proposed adding adjusters based on health status and prior utilization to the adjusted average per capita cost formula. The authors estimate how well such adjusters predict annual medical expenditures among non-elderly adults. Both measures substantially improve on the variables currently used. If only health measures are added, 20-30 percent of the predictable variance is explained; if only prior use is added, more than 40 percent is explained; if both are added, about 60 percent is explained. The results support including some measure of use in the formula until better health measures are developed. PMID:10313096

  4. Measuring Physical Activity Environments

    PubMed Central

    Sallis, James F.

    2010-01-01

    Physical activity is usually done in specific types of places, referred to as physical activity environments. These often include parks, trails, fitness centers, schools, and streets. In recent years, scientific interest has increased notably in measuring physical activity environments. The present paper provides an historical overview of the contributions of the health, planning, and leisure studies fields to the development of contemporary measures. The emphasis is on attributes of the built environment that can be affected by policies to contribute to the promotion of physical activity. Researchers from health fields assessed a wide variety of built environment variables expected to be related to recreational physical activity. Settings of interest were schools, workplaces, and recreation facilities, and most early measures used direct observation methods with demonstrated inter-observer reliability. Investigators from the city planning field evaluated aspects of community design expected to be related to people’s ability to walk from homes to destinations. GIS was used to assess walkability defined by the 3Ds of residential density, land-use diversity, and pedestrian-oriented designs. Evaluating measures for reliability or validity was rarely done in the planning-related fields. Researchers in the leisure studies and recreation fields studied mainly people’s use of leisure time rather than physical characteristics of parks and other recreation facilities. Although few measures of physical activity environments were developed, measures of aesthetic qualities are available. Each of these fields made unique contributions to the contemporary methods used to assess physical activity environments. PMID:19285214

  5. Satellite Infrared Radiation Measurements Prior to the Major Earthquakes

    NASA Technical Reports Server (NTRS)

    Ouzounov, Dimitar; Pulintes, S.; Bryant, N.; Taylor, Patrick; Freund, F.

    2005-01-01

    This work describes our search for a relationship between tectonic stresses and increases in mid-infrared (IR) flux as part of a possible ensemble of electromagnetic (EM) phenomena that may be related to earthquake activity. We present and &scuss observed variations in thermal transients and radiation fields prior to the earthquakes of Jan 22, 2003 Colima (M6.7) Mexico, Sept. 28 .2004 near Parkfield (M6.0) in California and Northern Sumatra (M8.5) Dec. 26,2004. Previous analysis of earthquake events has indicated the presence of an IR anomaly, where temperatures increased or did not return to its usual nighttime value. Our procedures analyze nighttime satellite data that records the general condtion of the ground after sunset. We have found from the MODIS instrument data that five days before the Colima earthquake the IR land surface nighttime temperature rose up to +4 degrees C in a 100 km radius around the epicenter. The IR transient field recorded by MODIS in the vicinity of Parkfield, also with a cloud free environment, was around +1 degree C and is significantly smaller than the IR anomaly around the Colima epicenter. Ground surface temperatures near the Parkfield epicenter four days prior to the earthquake show steady increase. However, on the night preceding the quake, a significant drop in relative humidity was indicated, process similar to those register prior to the Colima event. Recent analyses of continuous ongoing long- wavelength Earth radiation (OLR) indicate significant and anomalous variability prior to some earthquakes. The cause of these anomalies is not well understood but could be the result of a triggering by an interaction between the lithosphere-hydrosphere and atmospheric related to changes in the near surface electrical field and/or gas composition prior to the earthquake. The OLR anomaly usually covers large areas surrounding the main epicenter. We have found strong anomalies signal (two sigma) along the epicentral area signals on Dec 21

  6. Improving the Performance of a Neural-Machine Interface for Artificial Legs Using Prior Knowledge of Walking Environment

    PubMed Central

    Huang, He; Dou, Zhi; Zhang, Fan; Nunnery, Michael J.

    2013-01-01

    A previously developed neural-machine interface (NMI) based on neuromuscular-mechanical fusion has showed promise for recognizing user locomotion modes; however, errors of NMI during mode transitions were observed, which may challenge its real application. This study aimed to investigate whether or not the prior knowledge of walking environment could further improve the NMI performance. Linear Discriminant Analysis (LDA)-based classifiers were designed to identify user intent based on electromyographic (EMG) signals from residual muscles of leg amputees and ground reaction force (GRF) measured from the prosthetic leg. The prior knowledge of the terrain in front of the user adjusted the prior possibility in the discriminant function. Therefore, the boundaries of LDA were adaptive to the prior knowledge of the walking environment. This algorithm was evaluated on a dataset collected from one patient with a transfemoral (TF) amputation. The preliminary results showed that the NMI with adaptive prior possibilities outperformed the NMI without using the prior knowledge; it produced 98.7% accuracy for identifying tested locomotion modes, accurately predicted all the task transitions with 261–390 ms prediction time, and generated stable decision during task transitions. These results indicate the potential of using prior knowledge about walking environment to further improve the NMI for prosthetic legs. PMID:22255279

  7. PRIOR GENETIC CORRELATIONS AND NON-MEASURED TRAITS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current international genetic evaluations are based on how related country populations are genetically (across-country genetic correlations). Those correlations may be influenced strongly by prior expectations that were not based on sound scientific principles. Objective methods to predict prior cor...

  8. Measuring the Natural Environment

    NASA Astrophysics Data System (ADS)

    Strangeways, Ian

    2003-11-01

    This new edition has been brought completely up-to-date and expanded considerably. It has five new chapters covering visibility, clouds, lightning, atmospheric composition, and the upper atmosphere. The chapter on barometric pressure has been rewritten and expanded, while the chapter on oceans and polar regions has been split into two separate and expanded chapters. In addition, the final chapter--Forward Look--has been rewritten. This volume will be important reading for all professionals involved in pure environmental research or in the day-to-day management of the environment. First Edition Hb (2000): 0-521-57310-6

  9. Interplay of Prior Knowledge, Self-Regulation and Motivation in Complex Multimedia Learning Environments

    ERIC Educational Resources Information Center

    Song, H. S.; Kalet, A. L.; Plass, J. L.

    2016-01-01

    This study examined the direct and indirect effects of medical clerkship students' prior knowledge, self-regulation and motivation on learning performance in complex multimedia learning environments. The data from 386 medical clerkship students from six medical schools were analysed using structural equation modeling. The structural model revealed…

  10. Learning gait of quadruped robot without prior knowledge of the environment

    NASA Astrophysics Data System (ADS)

    Xu, Tao; Chen, Qijun

    2012-09-01

    Walking is the basic skill of a legged robot, and one of the promising ways to improve the walking performance and its adaptation to environment changes is to let the robot learn its walking by itself. Currently, most of the walking learning methods are based on robot vision system or some external sensing equipment to estimate the walking performance of certain walking parameters, and therefore are usually only applicable under laboratory condition, where environment can be pre-defined. Inspired by the rhythmic swing movement during walking of legged animals and the behavior of their adjusting their walking gait on different walking surfaces, a concept of walking rhythmic pattern(WRP) is proposed to evaluate the walking specialty of legged robot, which is just based on the walking dynamics of the robot. Based on the onboard acceleration sensor data, a method to calculate WRP using power spectrum in frequency domain and diverse smooth filters is also presented. Since the evaluation of WRP is only based on the walking dynamics data of the robot's body, the proposed method doesn't require prior knowledge of environment and thus can be applied in unknown environment. A gait learning approach of legged robots based on WRP and evolution algorithm(EA) is introduced. By using the proposed approach, a quadruped robot can learn its locomotion by its onboard sensing in an unknown environment, where the robot has no prior knowledge about this place. The experimental result proves proportional relationship exits between WRP match score and walking performance of legged robot, which can be used to evaluate the walking performance in walking optimization under unknown environment.

  11. Enhancement of Auditory Fear Conditioning after Housing in a Complex Environment Is Attenuated by Prior Treatment with Amphetamine

    ERIC Educational Resources Information Center

    Briand, Lisa A.; Robinson, Terry E.; Maren, Stephen

    2005-01-01

    Prior exposure to drugs of abuse has been shown to occlude the structural plasticity associated with living in a complex environment. Amphetamine treatment may also occlude some cognitive advantages normally associated with living in a complex environment. To test this hypothesis we examined the influence of prior exposure to amphetamine on fear…

  12. Review of Prior U.S. Attribute Measurement Systems

    SciTech Connect

    White, G K

    2012-07-06

    Attribute Measurement Systems have been developed and demonstrated several times in the United States over the last decade or so; under the Trilateral Initiative (1996-2002), FMTTD (Fissile Material Transparency Technology Demonstration, 2000), and NG-AMS (Next Generation Attribute Measurement System, 2005-2008). Each Attribute Measurement System has contributed to the growing body of knowledge regarding the use of such systems in warhead dismantlement and other Arms Control scenarios. The Trilateral Initiative, besides developing prototype hardware/software, introduced the topic to the international community. The 'trilateral' parties included the United States, the Russian Federation, and the International Atomic Energy Agency (IAEA). With the participation of a Russian delegation, the FMTTD demonstrated that measurements behind an information barrier are feasible while meeting host party security requirements. The NG-AMS system explored the consequences of maximizing the use of Commercial off the Shelf (COTS) equipment, which made construction easier, but authentication harder. The 3rd Generation Attribute Measurement System (3G-AMS) will further the scope of previous systems by including additional attributes and more rigor in authentication.

  13. Ultrasonic metal sheet thickness measurement without prior wave speed calibration

    NASA Astrophysics Data System (ADS)

    Dixon, S.; Petcher, P. A.; Fan, Y.; Maisey, D.; Nickolds, P.

    2013-11-01

    Conventional ultrasonic mensuration of sample thickness from one side only requires the bulk wave reverberation time and a calibration speed. This speed changes with temperature, stress, and microstructure, limiting thickness measurement accuracy. Often, only one side of a sample is accessible, making in situ calibration impossible. Non-contact ultrasound can generate multiple shear horizontal guided wave modes on one side of a metal plate. Measuring propagation times of each mode at different transducer separations, allows sheet thickness to be calculated to better than 1% accuracy for sheets of at least 1.5 mm thickness, without any calibration.

  14. Satellite IR Thermal Measurements Prior to the September 2004 Earthquakes in Central California

    NASA Technical Reports Server (NTRS)

    Ouzounov, D.; Logan, T.; Taylor, Patrick

    2004-01-01

    We present and discuss observed variations in thermal transients and radiation fields prior to the earthquakes of September 18 near Bodie (M5.5) and September 28,2004 near Parkfield(M6.0) in California. Previous analysis of earthquake events have indicated the presence of a thermal anomaly, where temperatures increased or did not return to its usual nighttime value. The procedures used in our work is to analyze weather satellite data taken at night and to record the general condition where the ground cools after sunset. Two days before the Bodie earthquake lower temperature radiation was observed by the NOAA/AVHRR satellite. This occurred when the entire region was relatively cloud-free. IR land surface nighttime temperature from the MODIS instrument rose to +4 C in a 100 km radius around the Bodie epicenter. The thermal transient field recorded by MODIS in the vicinity of Parkfield, also with a cloud free environment, was around +l C and it is significantly smaller than the Parkfield epicenter, however, for that period showed a steady increase 4 days prior to the earthquake and a significant drop of the night before the quake. Geosynchronous weather satellite thermal IR measurements taken every half hour from sunset to dawn, were also recorded for 10 days prior to the Parkfield event and 5 days after as well as the day of the quake. To establish a baseline we also obtained GOES data for the same Julian sets were then used to systematically observe and record any thermal anomaly prior to the events that deviated from the baseline. Our recent results support the hypothesis of a possible relationship between an thermodynamic processes produced by increasing tectonic stress in the Earth's crust and a subsequent electro-chemical interaction between this crust and the atmosphere/ionosphere.

  15. Environment-Assisted Precision Measurement

    SciTech Connect

    Goldstein, G.; Maze, J. R.; Lukin, M. D.; Cappellaro, P.; Hodges, J. S.; Jiang, L.; Soerensen, A. S.

    2011-04-08

    We describe a method to enhance the sensitivity of precision measurements that takes advantage of the environment of a quantum sensor to amplify the response of the sensor to weak external perturbations. An individual qubit is used to sense the dynamics of surrounding ancillary qubits, which are in turn affected by the external field to be measured. The resulting sensitivity enhancement is determined by the number of ancillas that are coupled strongly to the sensor qubit; it does not depend on the exact values of the coupling strengths and is resilient to many forms of decoherence. The method achieves nearly Heisenberg-limited precision measurement, using a novel class of entangled states. We discuss specific applications to improve clock sensitivity using trapped ions and magnetic sensing based on electronic spins in diamond.

  16. Environment-assisted precision measurement.

    PubMed

    Goldstein, G; Cappellaro, P; Maze, J R; Hodges, J S; Jiang, L; Sørensen, A S; Lukin, M D

    2011-04-01

    We describe a method to enhance the sensitivity of precision measurements that takes advantage of the environment of a quantum sensor to amplify the response of the sensor to weak external perturbations. An individual qubit is used to sense the dynamics of surrounding ancillary qubits, which are in turn affected by the external field to be measured. The resulting sensitivity enhancement is determined by the number of ancillas that are coupled strongly to the sensor qubit; it does not depend on the exact values of the coupling strengths and is resilient to many forms of decoherence. The method achieves nearly Heisenberg-limited precision measurement, using a novel class of entangled states. We discuss specific applications to improve clock sensitivity using trapped ions and magnetic sensing based on electronic spins in diamond. PMID:21561175

  17. Temperature, hydric environment, and prior pathogen exposure alter the experimental severity of chytridiomycosis in boreal toads

    USGS Publications Warehouse

    Murphy, Peter J.; St-Hilaire, Sophie; Corn, Paul Stephen

    2011-01-01

    Prevalence of the pathogen Batrachochytrium dendrobatidis (Bd), implicated in amphibian population declines worldwide, is associated with habitat moisture and temperature, but few studies have varied these factors and measured the response to infection in amphibian hosts. We evaluated how varying humidity, contact with water, and temperature affected the manifestation of chytridiomycosis in boreal toads Anaxyrus (Bufo) boreas boreas and how prior exposure to Bd affects the likelihood of survival after re-exposure, such as may occur seasonally in long-lived species. Humidity did not affect survival or the degree of Bd infection, but a longer time in contact with water increased the likelihood of mortality. After exposure to ~106 Bd zoospores, all toads in continuous contact with water died within 30 d. Moreover, Bd-exposed toads that were disease-free after 64 d under dry conditions, developed lethal chytridiomycosis within 70 d of transfer to wet conditions. Toads in unheated aquaria (mean = 15°C) survived less than 48 d, while those in moderately heated aquaria (mean = 18°C) survived 115 d post-exposure and exhibited behavioral fever, selecting warmer sites across a temperature gradient. We also found benefits of prior Bd infection: previously exposed toads survived 3 times longer than Bd-naïve toads after re-exposure to 106 zoospores (89 vs. 30 d), but only when dry microenvironments were available. This study illustrates how the outcome of Bd infection in boreal toads is environmentally dependent: when continuously wet, high reinfection rates may overwhelm defenses, but periodic drying, moderate warming, and previous infection may allow infected toads to extend their survival.

  18. Aircraft Lightning Electromagnetic Environment Measurement

    NASA Technical Reports Server (NTRS)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.

    2011-01-01

    This paper outlines a NASA project plan for demonstrating a prototype lightning strike measurement system that is suitable for installation onto research aircraft that already operate in thunderstorms. This work builds upon past data from the NASA F106, FAA CV-580, and Transall C-180 flight projects, SAE ARP5412, and the European ILDAS Program. The primary focus is to capture airframe current waveforms during attachment, but may also consider pre and post-attachment current, electric field, and radiated field phenomena. New sensor technologies are being developed for this system, including a fiber-optic Faraday polarization sensor that measures lightning current waveforms from DC to over several Megahertz, and has dynamic range covering hundreds-of-volts to tens-of-thousands-of-volts. A study of the electromagnetic emission spectrum of lightning (including radio wave, microwave, optical, X-Rays and Gamma-Rays), and a compilation of aircraft transfer-function data (including composite aircraft) are included, to aid in the development of other new lightning environment sensors, their placement on-board research aircraft, and triggering of the onboard instrumentation system. The instrumentation system will leverage recent advances in high-speed, high dynamic range, deep memory data acquisition equipment, and fiber-optic interconnect.

  19. Cold Environment Fogs And Measurements

    NASA Astrophysics Data System (ADS)

    Jiusto, James E.; Lala, G. Garland

    1983-09-01

    For several years radiation fog field programs have been conducted at Albany, NY, with an emphasis on understanding the basic mechanisms leading to dense fog formation. This past year a cooperative effort ("Fog Project-1982") involved nine university, federal and private research laboratories, including NCAR staff and their remote system of 25 portable automated mesonet (PAM) weather stations. A number of comprehensive data sets (boundary layer meteorology and cloud physics variables) during the 14-16 hour nocturnal evolution of fog have been obtained. In particular, the extinction of light in the visible and infrared (10.6 pm wavelength), associated visibility, drop size distributions, liquid water content, and vertical tethered-balloon soundings provided new insights into the structure of fog. A CO2 laser transmissometer was developed that yielded direct information on fog density. During October of 1981 and 1982, a number of radiation fogs occurred that were super-cooled in their lowest 20-50 m. This posed certain troublesome to critical measurement problems with several instruments. Cold environment techniques were devised to overcome some of these instrumentation difficulties.

  20. Specimen mass measurement. [during space environment simulation

    NASA Technical Reports Server (NTRS)

    Thornton, W. E.; Ord, J.

    1973-01-01

    The Skylab specimen mass measurement device was operated throughout the altitude test in close simulation of the 56-day Skylab mission. It performed operational specimen measurements well until it was passed out of the chamber for replacement of the specimen hold-down and was autoclaved prior to return. Fecal measurements were typically made with less than one percent error.

  1. Water-Level Measurements for the Coastal Plain Aquifers of South Carolina Prior to Development

    USGS Publications Warehouse

    Aucott, Walter R.; Speiran, Gary K.

    1984-01-01

    Tabulations of water-level measurements for the Coastal Plain aquifers of South Carolina representing water levels prior to man-made development are presented. Included with the tabulations are local well number, location, land-surface altitude, well depth, screened interval, depth to water, water- level altitude, and date measured. These water-level measurements were used in compiling regional potentiometric maps for the Coastal Plain aquifers. This data set will be useful in the planning for future water-resource development.

  2. Abundance measurements in stellar environments

    NASA Astrophysics Data System (ADS)

    Leone, F.

    2014-05-01

    Most of what we know about stars, and systems of stars, is derived from the analysis of their electromagnetic radiation. This lesson is an attempt to describe to Physicists, without any Astrophysical background, the framework to understand the present status of abundance determination in stellar environments and its limit. These notes are dedicated to the recently passed, November 21, 2013, Prof. Dimitri Mihalas who spent his life confuting the 19th century positivist philosopher Auguste Comte who stated that we shall not at all be able to determine the chemical composition of stars.

  3. Abundance measurements in stellar environments

    SciTech Connect

    Leone, F.

    2014-05-09

    Most of what we know about stars, and systems of stars, is derived from the analysis of their electromagnetic radiation. This lesson is an attempt to describe to Physicists, without any Astrophysical background, the framework to understand the present status of abundance determination in stellar environments and its limit. These notes are dedicated to the recently passed, November 21, 2013, Prof. Dimitri Mihalas who spent his life confuting the 19th century positivist philosopher Auguste Comte who stated that we shall not at all be able to determine the chemical composition of stars.

  4. Continuous quantum measurement in spin environments

    NASA Astrophysics Data System (ADS)

    Xie, Dong; Wang, An Min

    2015-08-01

    We derive a stochastic master equation (SME) which describes the decoherence dynamics of a system in spin environments conditioned on the measurement record. Markovian and non-Markovian nature of environment can be revealed by a spectroscopy method based on weak continuous quantum measurement. On account of that correlated environments can lead to a non-local open system which exhibits strong non-Markovian effects although the local dynamics are Markovian, the spectroscopy method can be used to demonstrate that there is correlation between two environments.

  5. Economic measurement of environment damages

    SciTech Connect

    Krawiec, F.

    1980-05-01

    The densities, energy consumption, and economic development of the increasing population exacerbate environmental degradation. Air and water pollution is a major environmental problem affecting life and health, outdoor recreation, household soiling, vegetation, materials, and production. The literature review indicated that numerous studies have assessed the physical and monetary damage to populations at risk from excessive concentrations of major air and water pollutants-sulfur dioxide, total suspended particulate matter, oxidants, and carbon monoxide in air; and nutrients, oil, pesticides, and toxic metals and others in water. The measurement of the damages was one of the most controversial issues in pollution abatement. The methods that have been used to estimate the societal value of pollution abatement are: (1) chain of effects, (2) market approaches, and (3) surveys. National gross damages of air pollution of $20.2 billion and of water pollution of $11.1 billion for 1973 are substantial. These best estimates, updated for the economic and demographic conditions, could provide acceptable control totals for estimating and predicting benefits and costs of abating air and water pollution emissions. The major issues to be resolved are: (1) lack of available noneconomic data, (2) theoretical and empirical difficulties of placing a value on human life and health and on benefits such as aesthetics, and (3) lack of available demographic and economic data.

  6. Measuring the Built Environment for Physical Activity

    PubMed Central

    Brownson, Ross C.; Hoehner, Christine M.; Day, Kristen; Forsyth, Ann; Sallis, James F.

    2009-01-01

    Physical inactivity is one of the most important public health issues in the U.S. and internationally. Increasingly, links are being identified between various elements of the physical—or built—environment and physical activity. To understand the impact of the built environment on physical activity, the development of high-quality measures is essential. Three categories of built environment data are being used: (1) perceived measures obtained by telephone interview or self-administered questionnaires; (2) observational measures obtained using systematic observational methods (audits); and (3) archival data sets that are often layered and analyzed with GIS. This review provides a critical assessment of these three types of built-environment measures relevant to the study of physical activity. Among perceived measures, 19 questionnaires were reviewed, ranging in length from 7 to 68 questions. Twenty audit tools were reviewed that cover community environments (i.e., neighborhoods, cities), parks, and trails. For GIS-derived measures, more than 50 studies were reviewed. A large degree of variability was found in the operationalization of common GIS measures, which include population density, land-use mix, access to recreational facilities, and street pattern. This first comprehensive examination of built-environment measures demonstrates considerable progress over the past decade, showing diverse environmental variables available that use multiple modes of assessment. Most can be considered first-generation measures, so further development is needed. In particular, further research is needed to improve the technical quality of measures, understand the relevance to various population groups, and understand the utility of measures for science and public health. PMID:19285216

  7. Detection of architectural distortion in prior mammograms using statistical measures of orientation of texture

    NASA Astrophysics Data System (ADS)

    Chakraborty, Jayasree; Rangayyan, Rangaraj M.; Banik, Shantanu; Mukhopadhyay, Sudipta; Desautels, J. E. L.

    2012-03-01

    We present a method using statistical measures of the orientation of texture to characterize and detect architectural distortion in prior mammograms of interval-cancer cases. Based on the orientation field, obtained by the application of a bank of Gabor filters to mammographic images, two types of co-occurrence matrices were derived to estimate the joint occurrence of the angles of oriented structures. For each of the matrices, Haralick's 14 texture features were computed. From a total of 106 prior mammograms of 56 interval-cancer cases and 52 mammograms of 13 normal cases, 4,224 regions of interest (ROIs) were automatically obtained by applying Gabor filters and phase portrait analysis. For each ROI, statistical features were computed using the angle co-occurrence matrices. The performance of the features in the detection of architectural distortion was analyzed and compared with that of Haralick's features computed using the gray-level co-occurrence matrices of the ROIs. Using logistic regression for feature selection, an artificial neural network for classification, and the leave-one-image-out approach for cross-validation, the best result achieved was 0.77 in terms of the area under the receiver operating characteristic (ROC) curve. Analysis of the free-response ROC curve yielded a sensitivity of 80% at 5.4 false positives per image.

  8. Operational neuroscience: neurophysiological measures in applied environments.

    PubMed

    Kruse, Amy A

    2007-05-01

    There is, without question, an interest within the military services to understand, account for, and adapt to the cognitive state of the individual warfighter. As the field of neuroscience has matured through investments from numerous government agencies, we are on the cusp of being able to move confidently from the lab into the field--and deepen our understanding of the cognitive issues embedded in the warfighting environment. However, as we edge closer to this integration--it is critical for researchers in this arena to understand the landscape they are entering-reflected not only in the challenges of each task or operational environment but also in the individual differences intrinsic to each warfighter. The research papers in this section cover this spectrum, including individual differences and their prediction of adaptability to high-stress environments, the influence of sleep-deprivation on neurophysiological measures of stimulus categorization, neurophysiological measures of stress in the training environment and, finally, real-time neural measures of task engagement, mental workload and vigilance. It is clear from this research, and other work detailed in this supplement, that the judicious use of neuroscience, cognitive psychology, and physiology in the applied environment is desirable for both researchers and operators. In fact, we suggest that these investigations merit a field designation unto their own: Operational Neuroscience. It is our hope that the discussion of this new field of study will galvanize others to increase the confidence and utility of this research through their own investigations. PMID:17547320

  9. First gas flux measurements of conduit permeability decrease prior to Strombolian eruption at Stromboli volcano (Italy)

    NASA Astrophysics Data System (ADS)

    Tamburello, Giancarlo; Aiuppa, Alessandro; Lo Coco, Eleonora; Delle Donne, Dario; Ripepe, Maurizio; Bitetto, Marcello; D'Aleo, Roberto

    2016-04-01

    Strombolian eruptions can be described in terms of growth, coalescence, and rise of a gas pocket (aka slug) bursting at the surface of a vent. This model overlooks that the transition to explosive regimes is mostly controlled by the permeability in the upper part of a volcanic conduit. We report here on the first gas flux measurements of Strombolian explosions from a vent that exhibited a significant decrease of passive degassing tens of second prior to the onset of the explosion. This particular explosive activity took place during the July 2014 lava overflows, when the magma level inside the conduit rose up to the crater terrace. The amount of gas that accumulated before the eruption is incredibly similar to the amount of gas ejected during the explosion. This similarity suggests a mechanism of decrease of the shallow conduit permeability and a subsequent accumulation of gas behind a cap of cold magma. The accumulated gas is then released when the over-pressure can open a leak on the cap of cold magma. Our unprecedented results offer key and novel insights into the explosive degassing dynamics within the shallow conduit systems of this open-vent volcano and probably at many other basaltic volcanoes.

  10. Prior-to- and Post-Impact Fall Detection Using Inertial and Barometric Altimeter Measurements.

    PubMed

    Sabatini, Angelo Maria; Ligorio, Gabriele; Mannini, Andrea; Genovese, Vincenzo; Pinna, Laura

    2016-07-01

    This paper investigates a fall detection system based on the integration of an inertial measurement unit with a barometric altimeter (BIMU). The vertical motion of the body part the BIMU was attached to was monitored on-line using a method that delivered drift-free estimates of the vertical velocity and estimates of the height change from the floor. The experimental study included activities of daily living of seven types and falls of five types, simulated by a cohort of 25 young healthy adults. The downward vertical velocity was thresholded at 1.38 m/s, yielding 80% sensitivity (SE), 100% specificity (SP) and a mean prior-to-impact time of 157 ms (range 40-300 ms). The soft falls, i.e., those with downward vertical velocity above 0.55 m/s and below 1.38 m/s were analyzed post-impact. Six fall detection methods, tuned to achieve 100% SE, were considered to include features of impact, change of posture and height, singularly or in association with one another. No single feature allowed for 100% SP. The detection accuracy marginally improved when the height change was considered in association with either the impact or the change of posture; the post-impact fall detection method that analyzed the impact and the change of posture together achieved 100% SP. PMID:26259247

  11. Measuring residual accelerations in the Spacelab environment

    NASA Technical Reports Server (NTRS)

    Witherow, William K.

    1991-01-01

    A triglycine sulfate (TGS) crystal growth experiment carried out in Spacelab 3 flown onboard the Shuttle orbiter in 1985 is described. The TGS experiment was aimed at examining diffusion limited crystal growth by minimizing convection in the microgravity environment of the Spacelab. During the experiment tiny crystals were found floating free in the growth solution. Since the free crystals were in a viscous fluid, the 'noise' accelerations of the Shuttle were damped out. This made it possible to measure the constant gravitational acceleration by tracking the positions of these crystals. The velocities and accelerations obtained by these measurements are presented.

  12. The Development and Validation of an End-User Satisfaction Measure in a Student Laptop Environment

    ERIC Educational Resources Information Center

    Kim, Sung; Meng, Juan; Kalinowski, Jon; Shin, Dooyoung

    2014-01-01

    The purpose of this paper is to present the development and validation of a measurement model for student user satisfaction in a laptop environment. Using a "quasi Delphi" method in addition to contributions from prior research we used EFA and CFA (LISREL) to identify a five factor (14 item) measurement model that best fit the data. The…

  13. MSL-RAD radiation environment measurements.

    PubMed

    Guo, Jingnan; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Hassler, Donald M; Ehresmann, Bent; Köhler, Jan; Böhm, Eckart; Böttcher, Stephan; Brinza, David; Burmeister, Sönke; Cucinotta, Francis; Martin, Cesar; Posner, Arik; Rafkin, Scot; Reitz, Guenther

    2015-09-01

    In this study, results are presented from the on-board radiation assessment detector (RAD) of Mars Science Laboratory (MSL). RAD is designed to measure the energetic particle radiation environment, which consists of galactic cosmic rays (GCRs) and solar energetic particles (SEPs) as well as secondary particles created by nuclear interactions of primary particles in the shielding (during cruise) or Martian soil and atmosphere (surface measurements). During the cruise, RAD collected data on space radiation from inside the craft, thus allowing for a reasonable estimation of what a human crew travelling to/from Mars might be exposed to. On the surface of Mars, RAD is shielded by the atmosphere (from above) and the planet itself (from below). RAD measures the first detailed radiation data from the surface of another planet, and they are highly relevant for planning future crewed missions. The results for radiation dose and dose equivalent (a quantity most directly related to human health risk) are presented during the cruise phase, as well as on the Martian surface. Dose and dose equivalent are dominated by the continuous GCR radiation, but several SEP events were also detected and are discussed here. PMID:25969529

  14. Investigation of the Impact of Two Verbal Instruction Formats and Prior Knowledge on Student Learning in a Simulation-Based Learning Environment

    ERIC Educational Resources Information Center

    Liu, Han-Chin; Chuang, Hsueh-Hua

    2011-01-01

    This study investigated how the format of verbal instructions in computer simulations and prior knowledge (PK) affected 8th graders' cognitive load (CL) level and achievement in a multimedia learning environment. Although PK was not found to significantly affect student performance and CL level, instruction format was found to impact both.…

  15. MSL-RAD Radiation Environment Measurements

    NASA Astrophysics Data System (ADS)

    Zeitlin, Cary; Hassler, Donald; Wimmer-Schweingruber, Robert; Boehm, Eckart; Boettcher, Stephan; Brinza, David; Burmeister, Soenke; Cucinotta, Francis; Ehresmann, Bent; Guo, Jingnan; Koehler, Jan; Martin, Cesar; Posner, Arik; Rafkin, Scot; Reitz, Guenther; MSL Science Team

    2013-04-01

    We present results from the Radiation Assessment Detector (RAD) obtained during MSL's cruise to Mars and during the first 150 sols after Curiosity's successful landing. RAD is designed to measure the energetic particle environment, which consists of Galactic Cosmic Rays (GCRs), Solar Energetic Particles (SEPs), and the secondary particles created by nuclear interactions of primary GCRs in shielding. During cruise, RAD was asymmetrically shielded inside the spacecraft. On the surface, RAD is shielded by the atmosphere, and the radiation dose rate is seen to vary slightly as the column depth of the atmosphere varies on a diurnal cycle. RAD's cruise measurements are a unique data set that provide a reasonable simulation of what might be encountered by a human crew headed for Mars or for some other destination in deep space. RAD successfully operated for 220 days of the 253 day journey to Mars. RAD has also operated stably on the surface of Mars, returning the first detailed radiation data from the surface of another planet. The data from the surface are also highly relevant for planning future crewed missions. We will present results for radiation dose and dose equivalent (the quantity most directly related to human health risk) obtained with both cruise and surface data. Dose and dose equivalent are dominated by the continuous GCR radiation, but five significant SEP events were seen during cruise and will be discussed.

  16. Use of chromosome translocations for measuring prior environment exposures in humans

    SciTech Connect

    Tucker, J. D.

    1997-05-01

    Recent advances in cytogenetic methodology are beginning to have a major impact upon our ability to provide assessments of environmental exposure in humans. The advent of fluorescent-based techniques for `painting` whole chromosomes has made the analysis of chromosome translocations rapid, specific, sensitive and routine. Chromosome painting has been used to address a wide variety of scientific questions, resulting in an increased understanding of the biological consequences of adverse environmental exposure. This paper describes the use of chromosome translocations as a biological marker of exposure and effect in humans. The relevance of translocations is discussed, as are the advantages and disadvantages of painting compared to classical cytogenetic methods for translocation evaluation. The factors to consider in the use of translocations as a retrospective indicator of exposure are then described. Several theoretical parameters that are important to the use of translocations are provided, and the paper concludes with a vision for the future of cytogenetic methodology.

  17. Absolute Thickness Measurements on Coatings Without Prior Knowledge of Material Properties Using Terahertz Energy

    NASA Technical Reports Server (NTRS)

    Roth, Don J.; Cosgriff, Laura M.; Harder, Bryan; Zhu, Dongming; Martin, Richard E.

    2013-01-01

    This study investigates the applicability of a novel noncontact single-sided terahertz electromagnetic measurement method for measuring thickness in dielectric coating systems having either dielectric or conductive substrate materials. The method does not require knowledge of the velocity of terahertz waves in the coating material. The dielectric coatings ranged from approximately 300 to 1400 m in thickness. First, the terahertz method was validated on a bulk dielectric sample to determine its ability to precisely measure thickness and density variation. Then, the method was studied on simulated coating systems. One simulated coating consisted of layered thin paper samples of varying thicknesses on a ceramic substrate. Another simulated coating system consisted of adhesive-backed Teflon adhered to conducting and dielectric substrates. Alumina samples that were coated with a ceramic adhesive layer were also investigated. Finally, the method was studied for thickness measurement of actual thermal barrier coatings (TBC) on ceramic substrates. The unique aspects and limitations of this method for thickness measurements are discussed.

  18. Veterinary students’ perceptions of their learning environment as measured by the Dundee Ready Education Environment Measure

    PubMed Central

    2014-01-01

    Background The Dundee Ready Education Environment Measure (DREEM) has been widely used to evaluate the learning environment within health sciences education, however, this tool has not been applied in veterinary medical education. The aim of this study was to evaluate the reliability and validity of the DREEM tool in a veterinary medical program and to determine veterinary students’ perceptions of their learning environment. Methods The DREEM is a survey tool which quantitatively measures students’ perceptions of their learning environment. The survey consists of 50 items, each scored 0–4 on a Likert Scale. The 50 items are subsequently analysed within five subscales related to students’ perceptions of learning, faculty (teachers), academic atmosphere, and self-perceptions (academic and social). An overall score is obtained by summing the mean score for each subscale, with an overall possible score of 200. All students in the program were asked to complete the DREEM. Means and standard deviations were calculated for the 50 items, the five subscale scores and the overall score. Cronbach’s alpha was determined for the five subscales and overall score to evaluate reliability. Confirmatory factor analysis was used to evaluate construct validity. Results 224 responses (53%) were received. The Cronbach’s alpha for the overall score was 0.93 and for the five subscales were; perceptions of learning 0.85, perceptions of faculty 0.79, perceptions of atmosphere 0.81, academic self-perceptions 0.68, and social self-perceptions 0.72. Construct validity was determined to be acceptable (p < 0.001) and all items contributed to the overall validity of the DREEM. The overall DREEM score was 128.9/200, which is a positive result based on the developers’ descriptors and comparable to other health science education programs. Four individual items of concern were identified by students. Conclusions In this setting the DREEM was a reliable and valid tool to measure

  19. Does prior knowledge of safety effect help to predict how effective a measure will be?

    PubMed

    Elvik, R

    1996-05-01

    Studies evaluating the effects of traffic safety measures are often done for the purpose of predicting the effects of future applications of the measures. The predictive value of evaluation studies is unknown. Some general arguments for and against attributing a general predictive value to the results of evaluation studies are discussed. Predictability is shown to depend on many factors. Meta-analyses of evidence from evaluation studies can be used as a basis for testing the predictive performance of such studies. The predictive performance of studies that have evaluated the safety effects of road lighting and traffic separation is tested. Predictive performance is found to depend mainly on whether the results of evaluation studies are stable over time or exhibit a trend. In the latter case, predictions based on evidence accumulated before the trend became apparent can be very erroneous. It is shown that increasing the amount of evidence that predictions are based on does not necessarily make the predictions more accurate. More research does not always improve predictive performance. PMID:8799438

  20. Isotropic probability measures in infinite dimensional spaces: Inverse problems/prior information/stochastic inversion

    NASA Technical Reports Server (NTRS)

    Backus, George

    1987-01-01

    Let R be the real numbers, R(n) the linear space of all real n-tuples, and R(infinity) the linear space of all infinite real sequences x = (x sub 1, x sub 2,...). Let P sub n :R(infinity) approaches R(n) be the projection operator with P sub n (x) = (x sub 1,...,x sub n). Let p(infinity) be a probability measure on the smallest sigma-ring of subsets of R(infinity) which includes all of the cylinder sets P sub n(-1) (B sub n), where B sub n is an arbitrary Borel subset of R(n). Let p sub n be the marginal distribution of p(infinity) on R(n), so p sub n(B sub n) = p(infinity)(P sub n to the -1(B sub n)) for each B sub n. A measure on R(n) is isotropic if it is invariant under all orthogonal transformations of R(n). All members of the set of all isotropic probability distributions on R(n) are described. The result calls into question both stochastic inversion and Bayesian inference, as currently used in many geophysical inverse problems.

  1. Measuring Collaborative Consultation Practices in Natural Environments

    ERIC Educational Resources Information Center

    Basu, Semonti; Salisbury, Christine L.; Thorkildsen, Theresa A.

    2010-01-01

    This article describes the development of the "Triadic Intervention and Evaluation Rating Scale" (TIERS), a 33-item instrument designed to evaluate patterns of parent, service provider, and child interactions during early intervention sessions conducted in natural environments. Twenty-eight parent-provider-child triads were videotaped in home and…

  2. Telemetric measurement system of beehive environment conditions

    NASA Astrophysics Data System (ADS)

    Walendziuk, Wojciech; Sawicki, Aleksander

    2014-11-01

    This work presents a measurement system of beehive environmental conditions. The purpose of the device is to perform measurements of parameters such as ambient temperature, atmospheric pressure, internal temperature, humidity and sound level. The measured values were transferred to the MySQL database, which is located on an external server, with the use of GPRS protocol. A website presents the measurement data in the form of tables and graphs. The study also shows exemplary results of environmental conditions measurements recorded in the beehive by hour cycle.

  3. Multi-day convective-environmental evolution prior to tropical cyclone formation from geostationary satellite measurements

    NASA Astrophysics Data System (ADS)

    Chang, Minhee; Ho, Chang-Hoi; Park, Myung-Sook

    2016-04-01

    Tropical cyclones (TCs) are developed through persistent latent heating taken from deep convective process. By analyzing aircraft and polar-orbit satellite observations, distinct upper-level warm-core induced by strong updraft was found in pre-TCs while vertically uniform temperature profile is found in non-developers. Precipitation is also broader and more frequent in developing disturbances than in nondeveloping ones. However, large uncertainties remain in determining which disturbance will develop into TC by using observation snap-shots. Here, five-day systematic evolution of deep convection and environments in developing (80) and non-developing (491) disturbances are examined over the western North Pacific for 20072009 by using geostationary satellite observation. Daily, positive tendencies in the hourly time series of the area of the MTSAT-1R infrared (IR) and water vapor (WV) brightness temperature difference < 0 are used to define single diurnal convective burst (CB) event. In terms of single CB properties (duration, expanded convective area, maximum convective area, and expanding rate), developing and nondeveloping disturbances shows significantly different mean values in the statistics, but it is not effective to estimate TC genesis. The presence of continuous CB events more than two days (i.e. multi-day CB; mCB), however, is generally found in developing disturbances. Based on the presence and absence mCB in the IR-WV time series, two different evolutions from Day 1 to Day 5 of TC formation (non-development) are explored, in which Day 6 is set to be a TC formation day (Day5 as non-development vortex decaying day). The majority of developing disturbances with mCB (83 %) initially have stronger large-scale vorticity with low-level maxima, tend to have gradually increasing deep convective area and vorticities at low-to-upper troposphere. By contrast, few developing disturbances (17 %) without mCB are pre-conditioned by much weaker large-scale vorticity

  4. The Effects of Learners' Prior Knowledge, Self-Regulation, and Motivation on Learning Performance in Complex Multimedia Learning Environments

    ERIC Educational Resources Information Center

    Song, Hyuksoon S.

    2010-01-01

    Many medical schools have developed computer-based, multimedia learning environments to fill the knowledge gap and provide common cases and resources to students. However, considering that multimedia in education may impede effective learning if the characteristics of learners and tasks are not considered thoroughly in instructional design, it is…

  5. Exploring Relations among College Students' Prior Knowledge, Implicit Theories of Intelligence, and Self-Regulated Learning in a Hypermedia Environment

    ERIC Educational Resources Information Center

    Greene, Jeffrey Alan; Costa, Lara-Jeane; Robertson, Jane; Pan, Yi; Deekens, Victor M.

    2010-01-01

    Researchers and educators continue to explore how to assist students in the acquisition of conceptual understanding of complex science topics. While hypermedia learning environments (HLEs) afford unique opportunities to display multiple representations of these often abstract topics, students who do not engage in self-regulated learning (SRL) with…

  6. Statistical measures of orientation of texture for the detection of architectural distortion in prior mammograms of interval-cancer

    NASA Astrophysics Data System (ADS)

    Chakraborty, Jayasree; Rangayyan, Rangaraj M.; Banik, Shantanu; Mukhopadhyay, Sudipta; Leo Desautels, J. E.

    2012-07-01

    Architectural distortion is an important sign of early breast cancer. Due to its subtlety, it is often missed during screening. We propose a method to detect architectural distortion in prior mammograms of interval-cancer cases based on statistical measures of oriented patterns. Oriented patterns were analyzed in the present work because regions with architectural distortion contain a large number of tissue structures spread over a wide angular range. Two new types of cooccurrence matrices were derived to estimate the joint occurrence of the angles of oriented structures. Statistical features were computed from each of the angle cooccurrence matrices to discriminate sites of architectural distortion from falsely detected regions in normal parts of mammograms. A total of 4,224 regions of interest (ROIs) were automatically obtained from 106 prior mammograms of 56 interval-cancer cases and 52 mammograms of 13 normal cases with the application of Gabor filters and phase portrait analysis. For each ROI, Haralick's 14 features were computed using the angle cooccurrence matrices. The best result obtained in terms of the area under the receiver operating characteristic (ROC) curve with the leave-one-patient-out method was 0.76; the free-response ROC curve indicated a sensitivity of 80% at 4.2 false positives per patient.

  7. Measurements of the radiation environment on the APEX satellite

    SciTech Connect

    Sims, A.J.; Dyer, C.S.; Watson, C.J.; Peerless, C.L.

    1996-06-01

    The Cosmic Radiation Environment and Dosimetry experiment was built to accompany the CRUX (Cosmic Ray Upset) experiment on the USAF APEX satellite, launched in August 1994. Results of measurements of the space radiation environment are presented here while a companion paper presents CRUX measurements of upsets correlated with proton flux.

  8. Gyroscopic corrections improve wearable sensor data prior to measuring dynamic sway in the gait of people with Multiple Sclerosis.

    PubMed

    Brodie, Matthew A D; Psarakis, Michael; Hoang, Phu

    2016-09-01

    Accelerometers are incorporated into many consumer devices providing new ways to monitor gait, mobility, and fall risk. However, many health benefits have not been realised because of issues with data quality that results from gravitational 'cross-talk' when the wearable device is tilted. Here we present an adaptive filter designed to improve the quality of accelerometer data prior to measuring dynamic pelvic sway patterns during a six minute walk test in people with and without Multiple Sclerosis (MS). Optical motion capture was used as the gold standard. Improved wearable device accuracy (≤4.4% NRMSE) was achieved using gyroscopic corrections and scaling filter thresholds by step frequency. The people with MS presented significantly greater pelvis sway range to compensate for their lower limb weaknesses and joint contractures. The visualisation of asymmetric pelvic sway in people with MS illustrates the potential to better understand their mobility impairments for reducing fall risk. PMID:26866921

  9. Electromagnetic Measurements in an Active Oilfield Environment

    NASA Astrophysics Data System (ADS)

    Schramm, K. A.; Aldridge, D. F.; Bartel, L. C.; Knox, H. A.; Weiss, C. J.

    2015-12-01

    An important issue in oilfield development pertains to mapping and monitoring of the fracture distributions (either natural or man-made) controlling subsurface fluid flow. Although microseismic monitoring and analysis have been used for this purpose for several decades, there remain several ambiguities and uncertainties with this approach. We are investigating a novel electromagnetic (EM) technique for detecting and mapping hydraulic fractures in a petroleum reservoir by injecting an electrically conductive contrast agent into an open fracture. The fracture is subsequently illuminated by a strong EM field radiated by a large engineered antenna. Specifically, a grounded electric current source is applied directly to the steel casing of the borehole, either at/near the wellhead or at a deep downhole point. Transient multicomponent EM signals (both electric and magnetic) scattered by the conductivity contrast are then recorded by a surface receiver array. We are presently utilizing advanced 3D numerical modeling algorithms to accurately simulate fracture responses, both before and after insertion of the conductive contrast agent. Model results compare favorably with EM field data recently acquired in a Permian Basin oilfield. However, extraction of the very-low-amplitude fracture signatures from noisy data requires effective noise suppression strategies such as long stacking times, rejection of outliers, and careful treatment of natural magnetotelluric fields. Dealing with the ever-present "episodic EM noise" typical in an active oilfield environment (associated with drilling, pumping, machinery, traffic, etc.) constitutes an ongoing problem. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  10. Cassini magnetometer measurements in the Jovian environment

    NASA Astrophysics Data System (ADS)

    Dougherty, M. K.

    2001-05-01

    M. K. Dougherty, and the Cassini magnetometer team The recent Cassini flyby of Jupiter had the spacecraft flying along the dusk flank of the magnetosphere, a region which has only been visited very briefly before during the Ulysses outbound pass. The unique Cassini flyby resulted in the spacecraft making numerous entries into the magnetosheath region as well as into the magnetosphere itself. Initial results from the magnetometer instrument will be described including information concerning the solar wind IMF, the large amount of mirror mode activity measured within the magnetosheath and incursions into the magnetosphere proper.

  11. Polarimetric measurements of precipitation over urban environments

    NASA Astrophysics Data System (ADS)

    Pereira Filho, A. J.

    2009-04-01

    This study presents recent results of weather radar polarimetric measurements of clouds and rainfall system over Eastern S„o Paulo, Brazil, more specifically in the metropolitan area of S„o Paulo (MASP). Local direct circulation associated to its urban heat island and sea breeze inflow tends to generate very deep convection similar to the Amazon region in a matter of minutes. It is investigated the impact of pollutants on the cloud microphysics and induced effects on downdrafts, lighting, hail and others such as flash floods.

  12. Selection of key stressors to develop virtual environments for practicing stress management skills with military personnel prior to deployment.

    PubMed

    Bouchard, Stéphane; Baus, Oliver; Bernier, François; McCreary, Donald R

    2010-02-01

    Virtual environments (VEs) are presently being used to treat military personnel suffering from posttraumatic stress disorder (PTSD). In an attempt to reduce the risk of PTSD, VEs may also be useful for stress management training (SMT) to practice skills under stress, but such use necessitates the development of relevant stress-inducing scenarios and storyboards. This article describes the procedures followed to select which VEs could be built for the Canadian Forces. A review and analysis of the available literature and of data collected postdeployment from 1,319 respondents on the frequency of stressors and their association with psychological injuries were pulled together to propose eight potential virtual stressors that can be used to practice SMT: seeing dead bodies or uncovering human remains; knowing someone being seriously injured or killed; receiving artillery fire; being unable to help ill or wounded civilians because of the rules of engagement; seeing destroyed homes and villages; clearing and searching homes, caves, or bunkers; receiving small-arms fire; and participating in demining operations. Information reported in this article could also be useful to document traumatic stressors experienced in theater of operations and their potential impact on psychological injuries. PMID:20528298

  13. Measuring the Environment through Digital Images

    NASA Astrophysics Data System (ADS)

    Pickle, J.; Schloss, A. L.

    2009-12-01

    A network of sites for citizen scientists to take a consistent time sequence of digital photographs of the landscape and an Internet site (http://picturepost.unh.edu/) that efficiently stores and distributes the digital images creates a low-cost and sustainable resource for scientific environmental monitoring and formal and informal science education. Digital photographs taken from the same location and positioned in the same direction and orientation allow scientists to monitor a variety of environmental parameters, including plant health, growth, and phenology; erosion and deposition; water levels; and cloud and canopy cover. The PicturePost platform is simply an octagon placed in the center of a flat surface and secured to a post anchored in the ground or onto a building. The edges of the octagon allow positioning of the camera so the complete landscape may be photographed in less than a minute. A NASA-funded project, Digital Earth Watch (aka Measuring Vegetation Health, (http://mvh.sr.unh.edu) provides educational activities and background materials that help people learn about plants as environmental “green canaries” and about the basics of cameras and digital images. The website also provides free software to analyze digital images. Although this project has been in development for four years, it is only beginning to find partners in which the data support multiple efforts. A large part of this integration is a result of recent NASA funding, which has allowed a new website to be developed to archive and display the images. The developing collaborations and the development of the new website at the same time enhanced both efforts. Because the website could include tools/features that appealed to the collaborating groups, all participants contributed ideas facing fewer restrictions. PicturePost made from recycled plastic lumber.

  14. Serial Measurements of Apoptotic Cell Numbers Provide Better Acceptance Criterion for PBMC Quality than a Single Measurement Prior to the T Cell Assay

    PubMed Central

    Wunsch, Marie; Caspell, Richard; Kuerten, Stefanie; Lehmann, Paul V.; Sundararaman, Srividya

    2015-01-01

    As soon as Peripheral Blood Mononuclear Cells (PBMC) are isolated from whole blood, some cells begin dying. The rate of apoptotic cell death is increased when PBMC are shipped, cryopreserved, or stored under suboptimal conditions. Apoptotic cells secrete cytokines that suppress inflammation while promoting phagocytosis. Increased numbers of apoptotic cells in PBMC may modulate T cell functions in antigen-triggered T cell assays. We assessed the effect of apoptotic bystander cells on a T cell ELISPOT assay by selectively inducing B cell apoptosis using α-CD20 mAbs. The presence of large numbers of apoptotic B cells did not affect T cell functionality. In contrast, when PBMC were stored under unfavorable conditions, leading to damage and apoptosis in the T cells as well as bystander cells, T cell functionality was greatly impaired. We observed that measuring the number of apoptotic cells before plating the PBMC into an ELISPOT assay did not reflect the extent of PBMC injury, but measuring apoptotic cell frequencies at the end of the assay did. Our data suggest that measuring the numbers of apoptotic cells prior to and post T cell assays may provide more stringent PBMC quality acceptance criteria than measurements done only prior to the start of the assay. PMID:25585298

  15. Measuring the Dimensions of Serendipity in Digital Environments

    ERIC Educational Resources Information Center

    McCay-Peet, Lori; Toms, Elaine

    2011-01-01

    Introduction: Serendipitous information retrieval is the perhaps inevitable consequence of immersion in an information-rich environment. Just how well chance encounters are supported, however, within these environments varies and one of the challenges to the development of tools and systems to facilitate serendipity is measuring how well they…

  16. Measuring Language Learning Environments in Secondary Science Classrooms

    ERIC Educational Resources Information Center

    Webster, Beverley J.; Hazari, Anjali

    2009-01-01

    The purpose of this study was to explore a new learning environment instrument which could be used by teaching practitioners and other educators to measure the language learning environment in the secondary science classroom. The science teacher is central in creating science classrooms conductive to the language needs of students and should be…

  17. Measuring the Food Environment State of the Science

    PubMed Central

    Lytle, Leslie A.

    2009-01-01

    The past decades have seen an increased interest in understanding how the environment affects population health. In particular, public health practitioners and researchers alike are eager to know how the food environments of neighborhoods, schools, and worksites affect food choices and, ultimately, population risk for obesity and other diet-related chronic disease. However, the measurement tools for assessing the environment and the employed study designs have limited our ability to gain important ground. The field has not yet fully considered the psychometric properties of the environmental measurement tools, or how to deal with the copious amounts of data generated from many environmental measures. The field is dominated by research using unsophisticated study designs and has frequently failed to see the role of social and individual factors and how they interrelate with the physical environment. This paper examines some of the measurement issues to be considered as public health practitioners and researchers attempt to understand the impact of the food environment on the health of communities and takes a broad look at where the science currently is with regard to how the food environment is measured, thoughts on what issues may benefit from more deliberate inspection, and directions for future work. PMID:19285204

  18. High-precision Photogrammetric Surface Figure Measurements under Cryogenic Environment

    NASA Astrophysics Data System (ADS)

    Lou, Z.; Qian, Y.; Fan, S. H.; Liu, C. R.; Wang, H. R.; Zuo, Y. X.; Cheng, J. Q.; Yang, J.

    2016-01-01

    Limited by the working temperature of the measurement equipments, most of the high-precision surface figure measurement techniques cannot be applied under a cryogenic environment. This paper reports the first attempt to measure the surface figure of a high-precision terahertz reflector panel under low temperatures based on photogrammetry. The measurement employs a high resolution industrial camera sitting on an automatic experimental platform which enables photos been taken in an automatic fashion inside a climate chamber. A repeatable accuracy of 2.1 μm rms is achieved under the cryogenic environment. Furthermore, surface figure measured by a three-coordinate measuring machine under room temperature is used to calibrate the thickness variation of the paper targets. By this technique, the surface figure of an aluminum prototype panel of the 5 meter Dome A Terahertz Telescope (DATE5) is measured from room temperature down to -55°C.

  19. Direct methods for radionuclides measurement in water environment.

    PubMed

    Chernyaev, A; Gaponov, I; Kazennov, A

    2004-01-01

    The paper is devoted to the direct method of anthropogenic radionuclide measurement in the water environment. Opportunities of application of submersible gamma-spectrometers for in situ underwater measurements of gamma-radiating nuclides and also the direct method for 90Sr detection are considered. PMID:15162871

  20. Measuring Self-Regulation in Computer-Based Learning Environments

    ERIC Educational Resources Information Center

    Schraw, Gregory

    2010-01-01

    I provide a summary of the four invited articles in this special issue and compare and contrast different methods for measuring self-regulation in computer-based learning environments (CBLEs). I present a taxonomy that distinguishes between offline and online measures and further distinguishes subcategories within each of these categories. I…

  1. Quantifying Error in Survey Measures of School and Classroom Environments

    ERIC Educational Resources Information Center

    Schweig, Jonathan David

    2014-01-01

    Developing indicators that reflect important aspects of school and classroom environments has become central in a nationwide effort to develop comprehensive programs that measure teacher quality and effectiveness. Formulating teacher evaluation policy necessitates accurate and reliable methods for measuring these environmental variables. This…

  2. Estimation of measurement variance in the context of environment statistics

    NASA Astrophysics Data System (ADS)

    Maiti, Pulakesh

    2015-02-01

    The object of environment statistics is for providing information on the environment, on its most important changes over time, across locations and identifying the main factors that influence them. Ultimately environment statistics would be required to produce higher quality statistical information. For this timely, reliable and comparable data are needed. Lack of proper and uniform definitions, unambiguous classifications pose serious problems to procure qualitative data. These cause measurement errors. We consider the problem of estimating measurement variance so that some measures may be adopted to improve upon the quality of data on environmental goods and services and on value statement in economic terms. The measurement technique considered here is that of employing personal interviewers and the sampling considered here is that of two-stage sampling.

  3. Electrophysiological measurement of interest during walking in a simulated environment.

    PubMed

    Takeda, Yuji; Okuma, Takashi; Kimura, Motohiro; Kurata, Takeshi; Takenaka, Takeshi; Iwaki, Sunao

    2014-09-01

    A reliable neuroscientific technique for objectively estimating the degree of interest in a real environment is currently required in the research fields of neuroergonomics and neuroeconomics. Toward the development of such a technique, the present study explored electrophysiological measures that reflect an observer's interest in a nearly-real visual environment. Participants were asked to walk through a simulated shopping mall and the attractiveness of the shopping mall was manipulated by opening and closing the shutters of stores. During the walking task, participants were exposed to task-irrelevant auditory probes (two-stimulus oddball sequence). The results showed a smaller P2/early P3a component of task-irrelevant auditory event-related potentials and a larger lambda response of eye-fixation-related potentials in an interesting environment (i.e., open-shutter condition) than in a boring environment (i.e., closed-shutter condition); these findings can be reasonably explained by supposing that participants allocated more attentional resources to visual information in an interesting environment than in a boring environment, and thus residual attentional resources that could be allocated to task-irrelevant auditory probes were reduced. The P2/early P3a component and the lambda response may be useful measures of interest in a real visual environment. PMID:24892726

  4. Microgravity acceleration measurement and environment characterization science (17-IML-1)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Acceleration Measurement System (SAMS) is a general purpose instrumentation system designed to measure the accelerations onboard the Shuttle Orbiter and Shuttle/Spacelab vehicles. These measurements are used to support microgravity experiments and investigation into the microgravity environment of the vehicle. Acceleration measurements can be made at locations remote from the SAMS main instrumentation unit by the use of up to three remote triaxial sensor heads. The prime objective for SAMS on the International Microgravity Lab (IML-1) mission will be to measure the accelerations experienced by the Fluid Experiment System (FES). The SAMS acceleration measurements for FES will be complemented by low level, low frequency acceleration measurements made by the Orbital Acceleration Research Experiment (OARE) installed on the shuttle. Secondary objectives for SAMS will be to measure accelerations at several specific locations to enable the acceleration transfer function of the Spacelab module to be analyzed. This analysis effort will be in conjunction with similar measurements analyses on other Spacelab missions.

  5. Preserving Differential Privacy for Similarity Measurement in Smart Environments

    PubMed Central

    2014-01-01

    Advances in both sensor technologies and network infrastructures have encouraged the development of smart environments to enhance people's life and living styles. However, collecting and storing user's data in the smart environments pose severe privacy concerns because these data may contain sensitive information about the subject. Hence, privacy protection is now an emerging issue that we need to consider especially when data sharing is essential for analysis purpose. In this paper, we consider the case where two agents in the smart environment want to measure the similarity of their collected or stored data. We use similarity coefficient function (FSC) as the measurement metric for the comparison with differential privacy model. Unlike the existing solutions, our protocol can facilitate more than one request to compute FSC without modifying the protocol. Our solution ensures privacy protection for both the inputs and the computed FSC results. PMID:25221785

  6. Internal space charge measurement of materials in a space environment

    NASA Astrophysics Data System (ADS)

    Griseri, V.; Fukunaga, K.; Maeno, T.; Payan, D.; Laurent, C.; Levy, L.

    2003-09-01

    The charging/discharging effect produced by space environment on space vehicles are known but not fully identified yet. Experiments performed in laboratory in vacuum chamber that simulates spatial environment and the most realistic charge condition occurring in space have been developed in the last past forty years. A very small Pulse Electro-Acoustic space charge detection unit (mini-PEA) that can be mounted in a vacuum chamber, to measure internal space charges of materials in-situ during the irradiation has been developed. Several materials used in spatial environment such as Teflon®, and Kapton ® films on addition to PMMA films have been studied. The comparison and the good agreement between measured and calculated depth of penetration for electrons of given energy depending on the material nature contribute in the validation of the detection system and encourage us for further studies and development.

  7. Indirect Measures of Learning Transfer between Real and Virtual Environments

    ERIC Educational Resources Information Center

    Garrett, Michael; McMahon, Mark

    2013-01-01

    This paper reports on research undertaken to determine the effectiveness of a 3D simulation environment used to train mining personnel in emergency evacuation procedures, designated the Fires in Underground Mines Evacuation Simulator (FUMES). Owing to the operational constraints of the mining facility, methods for measuring learning transfer were…

  8. Measuring the Accuracy of Prediction in a Simulated Environment.

    ERIC Educational Resources Information Center

    Mailles, Stephanie; Batatia, Hadj

    1998-01-01

    Describes use of a computerized simulation to study prediction in a complex environment (i.e., bus traffic control). Nature of the task, presentation method, number of repetitions, and length of time taken for prediction were measured. Prediction was significantly affected by all factors except number of repetitions. No learning effect was…

  9. Measuring Performance of Virtual Learning Environment System in Higher Education

    ERIC Educational Resources Information Center

    Ho, William; Higson, Helen E.; Dey, Prasanta K.; Xu, Xiaowei; Bahsoon, Rami

    2009-01-01

    Purpose: The purpose of this paper is to measure the performance of commercial virtual learning environment (VLE) systems, which helps the decision makers to select the appropriate system for their institutions. Design/methodology/approach: This paper develops an integrated multiple criteria decision making approach, which combines the analytic…

  10. X-Ray Measurements Of Displacements In Hostile Environments

    NASA Technical Reports Server (NTRS)

    Fralick, Gustave C.; Canistraro, Howard A.; Jordan, Eric H.; Pease, Douglas M.

    1995-01-01

    Developmental method of noncontact extensometry of objects in hot or otherwise hostile environments based on focusing and scanning of x rays. Principal advantage: ability to make measurements through stratified and/or flowing gases, smoke, and flames, as well as through solid layers of x-ray-transparent materials.

  11. Measuring Self-Regulation in Online and Blended Learning Environments

    ERIC Educational Resources Information Center

    Barnard, Lucy; Lan, William Y.; To, Yen M.; Paton, Valerie Osland; Lai, Shu-Ling

    2009-01-01

    In developing the Online Self-regulated Learning Questionnaire (OSLQ) to address the need for an instrument measuring self-regulation in the online learning environment, this study provides evidence toward the reliability and validity of the instrument. Data were collected from two samples of students. The first sample of students took coursework…

  12. Recent Measurements of the Orbital Debris Environment at NASA Johnson Space Center

    NASA Technical Reports Server (NTRS)

    Stansbery, E. G.; Settecerri, T. J.; Africano, J. L.

    1999-01-01

    Space debris presents many challenges to current space operations. Although, the probability of collision between an operational spacecraft and a piece of space debris is quite small, the potential losses can be quite high. Prior to 1990, characterization of the orbital debris environment was divided into two categories. Objects larger than 10 cm are monitored by the United States Space Surveillance Network (SSN) and documented in the U.S. Space Command (USSPACECOM) catalog. Knowledge of debris smaller than 0.1 cm has come from the analyses of returned surfaces. The lack of information about the debris environment in the size range from 0.1 to 1 0 cm led to a joint NASA-DOD effort for orbital debris measurements using the Haystack radar and the unbuilt Haystack Auxiliary (HAX) radars. The data from these radars have been critical to the design of shielding for the International Space Station and have been extensively used in the creation of recent models describing the orbital debris environment. Recent debris campaigns have been conducted to verify and validate through comparative measurements, the results and conclusions drawn from the Haystack/HAX measurements. The Haystack/HAX measurements and results will be described as well as the results of the recent measurement campaigns.

  13. Filamentary Environment and Mass Measurements of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Noh, Yookyung

    2013-01-01

    Galaxy clusters reside at the nodes of cosmic web and are fed matter along the filaments. This filamentary environment is important to understand the formation and the evolution of galaxy clusters, and is also inevitably included when we observe them. This latter effect generates projection effects on cluster observables. Reducing errors in measuring cluster masses is of interest since a cluster's mass is a crucial property for many areas of astrophysics and cosmology. We study the filamentary environment surrounding galaxy clusters and its effect on the cluster mass measurements by constructing a filament catalogue in a high-resolution N-body simulation. We consider the statistical properties of filaments around galaxy clusters. Not only filaments but also the majority of mass in halos and number of galaxies in the local environment of clusters tends to lie on planes which are mostly aligned with each other and with the cluster's major axis. We show that this local planar environment can be one source of projection effects that bias cluster mass measurements. Sources of mass measurement scatters are shared between different mass measurement methods, generating correlations in their respective scatters. This correlated scatter mitigates the complementary information of cluster mass measurements in multi-wavelength observations. We study the scatter by calculating correlations/covariances between them and performing Principal Component Analysis (PCA). As expected, the scatter from different techniques tends to be correlated. We find that the combination of scatters which dominates the variance of all the measurements is common for the majority of clusters. Its dominance tends to be enhanced when observing along the cluster's major axis. We also find shared trends among cluster mass scatter, intrinsic and environmental properties of clusters using PCA.

  14. Measuring Work Environment and Performance in Nursing Homes

    PubMed Central

    Temkin-Greener, Helena; Zheng, Nan (Tracy); Katz, Paul; Zhao, Hongwei; Mukamel, Dana B.

    2008-01-01

    Background Qualitative studies of the nursing home work environment have long suggested that such attributes as leadership and communication may be related to nursing home performance, including residents' outcomes. However, empirical studies examining these relationships have been scant. Objectives This study is designed to: develop an instrument for measuring nursing home work environment and perceived work effectiveness; test the reliability and validity of the instrument; and identify individual and facility-level factors associated with better facility performance. Research Design and Methods The analysis was based on survey responses provided by managers (N=308) and direct care workers (N=7,418) employed in 162 facilities throughout New York State. Exploratory factor analysis, Chronbach's alphas, analysis of variance, and regression models were used to assess instrument reliability and validity. Multivariate regression models, with fixed facility effects, were used to examine factors associated with work effectiveness. Results The reliability and the validity of the survey instrument for measuring work environment and perceived work effectiveness has been demonstrated. Several individual (e.g. occupation, race) and facility characteristics (e.g. management style, workplace conditions, staffing) that are significant predictors of perceived work effectiveness were identified. Conclusions The organizational performance model used in this study recognizes the multidimensionality of the work environment in nursing homes. Our findings suggest that efforts at improving work effectiveness must also be multifaceted. Empirical findings from such a line of research may provide insights for improving the quality of the work environment and ultimately the quality of residents' care. PMID:19330892

  15. Temperature measurements using multicolor pyrometry in thermal radiation heating environments

    SciTech Connect

    Fu, Tairan; Liu, Jiangfan; Duan, Minghao; Zong, Anzhou

    2014-04-15

    Temperature measurements are important for thermal-structural experiments in the thermal radiation heating environments such as used for thermal-structural stress analyses. This paper describes the use of multicolor pyrometry for the measurements of diffuse surfaces in thermal radiation environments that eliminates the effects of background radiation reflections and unknown emissivities based on a least-squares algorithm. The near-infrared multicolor pyrometer had a spectral range of 1100–2400 nm, spectrum resolution of 6 nm, maximum sampling frequency of 2 kHz, working distance of 0.6 m to infinity, temperature range of 700–1700 K. The pyrometer wavelength response, nonlinear intensity response, and spectral response were all calibrated. The temperature of a graphite sample irradiated by quartz lamps was then measured during heating and cooling using the least-squares algorithm based on the calibrated irradiation data. The experiments show that higher temperatures and longer wavelengths are more suitable for the thermal measurements in the quartz lamp radiation heating system. This analysis provides a valuable method for temperature measurements of diffuse surfaces in thermal radiation environments.

  16. Optimizing quantum correlation dynamics by weak measurement in dissipative environment

    NASA Astrophysics Data System (ADS)

    Du, Shao-Jiang; Xia, Yun-Jie; Duan, De-Yang; Zhang, Lu; Gao, Qiang

    2015-04-01

    We investigate the protection of quantum correlations of two qubits in independent vacuum reservoirs by means of weak measurements. It is found that the weak measurement can reduce the amount of quantum correlation for one type of initial state at the beginning in a non-Markovian environment and meanwhile it can reduce the occurrence time of entanglement sudden death (ESD) in the process of time evolution. In a Markovian environment, the quantum entanglements of the two kinds of initial states decay rapidly and the weak measurement can further weaken the quantum entanglement, therefore in this case the entanglement cannot be optimized in the evolution process. Project supported by the National Natural Science Foundation of China (Grant Nos. 61178012 and No.11147019).

  17. Measuring the Internal Environment of Solid Rocket Motors During Ignition

    NASA Technical Reports Server (NTRS)

    Weisenberg, Brent; Smith, Doug; Speas, Kyle; Corliss, Adam

    2003-01-01

    A new instrumentation system has been developed to measure the internal environment of solid rocket test motors during motor ignition. The system leverages conventional, analog gages with custom designed, electronics modules to provide safe, accurate, high speed data acquisition capability. To date, the instrumentation system has been demonstrated in a laboratory environment and on subscale static fire test motors ranging in size from 5-inches to 24-inches in diameter. Ultimately, this system is intended to be installed on a full-scale Reusable Solid Rocket Motor. This paper explains the need for the data, the components and capabilities of the system, and the test results.

  18. Measuring Knowledge Acquisition in 3D Virtual Learning Environments.

    PubMed

    Nunes, Eunice P dos Santos; Roque, Licínio G; Nunes, Fatima de Lourdes dos Santos

    2016-01-01

    Virtual environments can contribute to the effective learning of various subjects for people of all ages. Consequently, they assist in reducing the cost of maintaining physical structures of teaching, such as laboratories and classrooms. However, the measurement of how learners acquire knowledge in such environments is still incipient in the literature. This article presents a method to evaluate the knowledge acquisition in 3D virtual learning environments (3D VLEs) by using the learner's interactions in the VLE. Three experiments were conducted that demonstrate the viability of using this method and its computational implementation. The results suggest that it is possible to automatically assess learning in predetermined contexts and that some types of user interactions in 3D VLEs are correlated with the user's learning differential. PMID:26915117

  19. Exposure Measurements in Japan Environment and Children's Study.

    PubMed

    Nakayama, Shoji

    2016-01-01

    The Japan Ministry of the Environment is conducting a large-scale birth cohort study called the Japan Environment and Children's Study (JECS), which involves 100000 mother-child pairs. Mothers are enrolled during pregnancy, and their children are followed up and studied until they reach the age of 13 years. The JECS started recruiting mothers in January 2011 and completed the registration of more than 103000 mothers in March 2014. The National Institute for Environmental Studies takes the lead in the study programming and implementation in cooperation with the National Centre for Child Health and Development and 15 Regional Centres that reach out to the study participants. In the study, the effects of environmental factors on children's health and development are investigated. The environment in this study is defined not only as air, soil, water, and indoor environments but also as various chemical substances, physical conditions, socioeconomic factors, psychological conditions, lifestyles and community situations. Mothers' and children's exposures to these environmental factors are measured through chemical analyses of biospecimens collected during pregnancy and after birth, questionnaires and computer modelling. The homes of the randomly selected participants (5000) are visited to measure the concentrations of volatile organic compounds, nitrogen and sulphuric oxides and particulate matter. Vacuum dust samples are also collected for chemical analysis. All these data will be combined with the information collected by the dwelling unit observation to assess the exposure of children aged 1.5 and 3 years. PMID:27252056

  20. Crack Growth Monitoring in Harsh Environments by Electric Potential Measurements

    SciTech Connect

    Lloyd, Wilson Randolph; Reuter, Walter Graham; Weinberg, David Michael

    1999-09-01

    Electric potential measurement (EPM) technology offers an attractive alternative to conventional nondestructive evaluation (NDE) for monitoring crack growth in harsh environments. Where conventional NDE methods typically require localized human interaction, the EPM technique developed at the Idaho National Engineering and Environmental Laboratory (INEEL) can be operated remotely and automatically. Once a crack-like defect is discovered via conventional means, EPM can be applied to monitor local crack size changes. This is of particular interest in situations where an identified structural defect is not immediately rejectable from a fitness-for-service viewpoint, but due to operational and environmental conditions may grow to an unsafe size with continuing operation. If the location is in a harsh environment where periodic monitoring by normal means is either too costly or not possible, a very expensive repair may be immediately mandated. However, the proposed EPM methodology may offer a unique monitoring capability that would allow for continuing service. INEEL has developed this methodology, supporting equipment, and calibration information to apply EPM in a field environment for just this purpose. Laboratory and pilot scale tests on full-size engineering structures (pressure vessels and piping) have been successfully performed. The technique applicable is many severe environments because the sensitive equipment (electronics, operators) can be situated in a remote location, with only current and voltage probe electrical leads entering into the harsh environment. Experimental results showing the utility of the methodology are presented, and unique application concepts that have been examined by multiple experiments are discussed.

  1. Crack growth monitoring in harsh environments by electrical potential measurements

    SciTech Connect

    W. R. Lloyd; W. G. Reuter; D. M. Weinberg

    1999-09-19

    Electric potential measurement (EPM) technology offers an attractive alternative to conventional nondestructive evaluation (NDE) for monitoring crack growth in harsh environments. Where conventional NDE methods typically require localized human interaction, the EPM technique developed at the Idaho National Engineering and Environmental Laboratory (INEEL) can be operated remotely and automatically. Once a crack-like defect is discovered via conventional means, EPM can be applied to monitor local crack size changes. This is of particular interest in situations where an identified structural defect is not immediately rejectable from a fitness-for-service viewpoint, but due to operational and environmental conditions may grow to an unsafe size with continuing operation. If the location is in a harsh environment where periodic monitoring by normal means is either too costly or not possible, a very expensive repair may be immediately mandated. However, the proposed EPM methodology may offer a unique monitoring capability that would allow for continuing service. INEEL has developed this methodology, supporting equipment, and calibration information to apply EPM in a field environment for just this purpose. Laboratory and pilot scale tests on full-size engineering structures (pressure vessels and piping) have been successfully performed. The technique is applicable to many severe environments because the sensitive equipment (electronics, operators) can be situated in a remote location, with only current and voltage probe electrical leads entering into the harsh environment. Experimental results showing the utility of the methodology are presented, and unique application concepts that have been examined by multiple experiments are discussed.

  2. Determining Transmission Loss from Measured External and Internal Acoustic Environments

    NASA Technical Reports Server (NTRS)

    Scogin, Tyler; Smith, A. M.

    2012-01-01

    An estimate of the internal acoustic environment in each internal cavity of a launch vehicle is needed to ensure survivability of Space Launch System (SLS) avionics. Currently, this is achieved by using the noise reduction database of heritage flight vehicles such as the Space Shuttle and Saturn V for liftoff and ascent flight conditions. Marshall Space Flight Center (MSFC) is conducting a series of transmission loss tests to verify and augment this method. For this test setup, an aluminum orthogrid curved panel representing 1/8th of the circumference of a section of the SLS main structure was mounted in between a reverberation chamber and an anechoic chamber. Transmission loss was measured across the panel using microphones. Data measured during this test will be used to estimate the internal acoustic environments for several of the SLS launch vehicle internal spaces.

  3. Advantages of High Tolerance Measurements in Fusion Environments Applying Photogrammetry

    SciTech Connect

    T. Dodson, R. Ellis, C. Priniski, S. Raftopoulos, D. Stevens, M. Viola

    2009-02-04

    Photogrammetry, a state-of-the-art technique of metrology employing digital photographs as the vehicle for measurement, has been investigated in the fusion environment. Benefits of this high tolerance methodology include relatively easy deployment for multiple point measurements and deformation/distortion studies. Depending on the equipment used, photogrammetric systems can reach tolerances of 25 microns (0.001 in) to 100 microns (0.004 in) on a 3-meter object. During the fabrication and assembly of the National Compact Stellarator Experiment (NCSX) the primary measurement systems deployed were CAD coordinate-based computer metrology equipment and supporting algorithms such as both interferometer-aided (IFM) and absolute distance measurementbased (ADM) laser trackers, as well as portable Coordinate Measurement Machine (CMM) arms. Photogrammetry was employed at NCSX as a quick and easy tool to monitor coil distortions incurred during welding operations of the machine assembly process and as a way to reduce assembly downtime for metrology processes.

  4. Assessing Built Environment Walkability using Activity-Space Summary Measures

    PubMed Central

    Tribby, Calvin P.; Miller, Harvey J.; Brown, Barbara B.; Werner, Carol M.; Smith, Ken R.

    2015-01-01

    There is increasing emphasis on active transportation, such as walking, in transportation planning as a sustainable form of mobility and in public health as a means of achieving recommended physical activity and better health outcomes. A research focus is the influence of the built environment on walking, with the ultimate goal of identifying environmental modifications that invite more walking. However, assessments of the built environment for walkability are typically at a spatially disaggregate level (such as street blocks) or at a spatially aggregate level (such as census block groups). A key issue is determining the spatial units for walkability measures so that they reflect potential walking behavior. This paper develops methods for assessing walkability within individual activity spaces: the geographic region accessible to an individual during a given walking trip. We first estimate street network-based activity spaces using the shortest path between known trip starting/ending points and a travel time budget that reflects potential alternative paths. Based on objective walkability measures of the street blocks, we use three summary measures for walkability within activity spaces: i) the average walkability score across block segments (representing the general level of walkability in the activity space); ii) the standard deviation (representing the walkability variation), and; iii) the network autocorrelation (representing the spatial coherence of the walkability pattern). We assess the method using data from an empirical study of built environment walkability and walking behavior in Salt Lake City, Utah, USA. We visualize and map these activity space summary measures to compare walkability among individuals’ trips within their neighborhoods. We also compare summary measures for activity spaces versus census block groups, with the result that they agree less than half of the time. PMID:27213027

  5. Visualization of Radiation Environment on Mars: Assessment with MARIE Measurements

    NASA Technical Reports Server (NTRS)

    Saganti, P.; Cucinotta, F.; Zeitlin, C.; Cleghorn, T.; Flanders, J.; Riman, F.; Hu, X.; Pinsky, L.; Lee, K.; Anderson, V.; Atwell, W.; Turner, R.

    2003-01-01

    For a given GCR (Galactic Cosmic Ray) environment at Mars, particle flux of protons, alpha particles, and heavy ions, are also needed on the surface of Mars for future human exploration missions. For the past twelve months, the MARJE (Martian Radiation Environment Experiment) instrument onboard the 200J Mars Odyssey has been providing the radiation measurements from the Martian orbit. These measurements are well correlated with the HZETRN (High Z and Energy Transport) and QMSFRG (Quantum Multiple-Scattering theory of nuclear Fragmentation) model calculations. These model calculations during these specific GCR environment conditions are now extended and transported through the CO2 atmosphere onto the Martian surface. These calculated pa11icle flux distributions are presented as a function of the Martian topography making use of the MOLA (Mars Orbiter Laser Altimeter) data from the MGS (Mars Global Surveyor). Also, particle flux calculations are presented with visualization in the human body from skin depth to the internal organs including the blood-forming organs.

  6. Radiation Environment Variations at Mars - Model Calculations and Measurements

    NASA Astrophysics Data System (ADS)

    Saganti, Premkumar; Cucinotta, Francis

    Variations in the space radiation environment due to changes in the GCR (Galactic Cosmic Ray) from the past (#23) solar cycle to the current one (#24) has been intriguing in many ways, with an unprecedented long duration of the recent solar minimum condition and a very low peak activity of the current solar maximum. Model calculated radiation data and assessment of variations in the particle flux - protons, alpha particles, and heavy ions of the GCR environment is essential for understanding radiation risk and for any future intended long-duration human exploration missions. During the past solar cycle, we have had most active and higher solar maximum (2001-2003) condition. In the beginning of the current solar cycle (#24), we experienced a very long duration of solar minimum (2009-2011) condition with a lower peak activity (2013-2014). At Mars, radiation measurements in orbit were obtained (onboard the 2001 Mars Odyssey spacecraft) during the past (#23) solar maximum condition. Radiation measurements on the surface of Mars are being currently measured (onboard the Mars Science Laboratory, 2012 - Curiosity) during the current (#24) solar peak activity (August 2012 - present). We present our model calculated radiation environment at Mars during solar maxima for solar cycles #23 and #24. We compare our earlier model calculations (Cucinotta et al., J. Radiat. Res., 43, S35-S39, 2002; Saganti et al., J. Radiat. Res., 43, S119-S124, 2002; and Saganti et al., Space Science Reviews, 110, 143-156, 2004) with the most recent radiation measurements on the surface of Mars (2012 - present).

  7. Measurement of Radiation Pressure in an Ambient Environment

    NASA Astrophysics Data System (ADS)

    Ma, Dakang; Garrett, Joseph; Munday, Jeremy

    2015-03-01

    Light has momentum and thus exerts ``radiation pressure'' when it is reflected or absorbed due to the conservation of momentum. Micromechanical transducers and oscillators are suitable for measurement and utilization of radiation pressure due to their high sensitivities. However, other light-induced mechanical deformations such as photothermal effects often obscure accurate measurements of radiation pressure in these systems. In this work, we investigate the radiation pressure and photothermal force on an uncoated silicon nitride microcantilever under illumination by a 660 nm laser in an ambient environment. To magnify the mechanical effects, the cantilever is driven optically from dc across its resonance frequency, and the amplitude and phase of its oscillation are acquired by an optical beam deflection method and a lockin amplifier. We show that radiation pressure and photothermal effects can be distinguished through the cantilever's frequency response. Furthermore, in a radiation pressure dominant regime, our measurement of the radiation force agrees quantitatively with the theoretical calculation.

  8. Correlations between LDEX Measurements and the Lunar Plasma Environment

    NASA Astrophysics Data System (ADS)

    Szalay, Jamey; Horanyi, Mihaly; Poppe, Andrew; Halekas, Jasper

    2014-05-01

    The Lunar Dust Experiment (LDEX) aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) is an impact ionization dust detector capable of measuring the mass of sub-micron sized dust grains above the lunar surface. LDEX can also search for the putative population of grains with radii on the order of ~ 0.1 μm lofted over the terminator regions by measuring the collective current of dust grains that are below the detection threshold for single impacts. This current, intended to measure the collective impact plasma from multiple small grain impacts, has also shown considerable correlations with plasma measurements from the ARTEMIS (Acceleration, Reconnection, Turbulence, & Electrodynamics of Moon's Interaction with the Sun) mission. Through LADEE's many orbits, LDEX sees time periods with very low variability, having almost no activity as well as periods with very high variability. Since this type of high activity is also observed in anti-ram pointing measurements, much of this current cannot be explained by collections of small dust grain impacts. Given this, comparisons to ARTEMIS data provide a promising way to explain such measurements. This presentation will focus on the correlations between LDEX and ARTEMIS data.

  9. TDLAS for measurement of temperature in combustion environment

    NASA Astrophysics Data System (ADS)

    Liu, Pei-jin; Huang, Bin; Yang, Bin; He, Guo-qiang

    2013-05-01

    Tunable Diode Laser Absorption Spectroscopy (TDLAS) technique has many significant advantages such as non-intrusive compared with traditional combustion parameter measurement techniques. In this paper, according to the absorption lines optimization criterions, the 7444.352+7444.371 cm-1 and 7185.597 cm-1 line pair of water vapor (H2O) is selected for the temperature measurement of combustion environment in 900-1600K region, and two most important influencing factors (temperature and pressure) are analyzed by simulation of absorption spectrum based on HITRAN. Therefore, TDLAS system using the 7444.352+7444.371 cm-1 and 7185.597 cm-1 line pair based on Time-Division-multiplexing (TDM) strategy has been designed. This TDLAS system has been applied for the temperature measurement in the exhaust of Rocket Based Combined Cycle (RBCC) engine. Compared with the pressure measured by the pressure transducer in combustion chamber, the tendency of temperature measurement has well agreement with the pressure. The result of temperature measurement using TDLAS technique has great importance to the evaluation of RBCC combustion efficiency.

  10. Disparities in neighborhood food environments: implications of measurement strategies.

    PubMed

    Bader, Michael D M; Purciel, Marnie; Yousefzadeh, Paulette; Neckerman, Kathryn M

    2010-01-01

    Public health researchers have begun to map the neighborhood “food environment” and examine its association with the risk of overweight and obesity. Some argue that “food deserts”—areas with little or no provision of fresh produce and other healthy food—may contribute to disparities in obesity, diabetes, and related health problems. While research on neighborhood food environments has taken advantage of more technically sophisticated ways to assess distance and density, in general, it has not considered how individual or neighborhood conditions might modify physical distance and thereby affect patterns of spatial accessibility. This study carried out a series of sensitivity analyses to illustrate the effects on the measurement of disparities in food environments of adjusting for cross-neighborhood variation in vehicle ownership rates, public transit access, and impediments to pedestrian travel, such as crime and poor traffic safety. The analysis used geographic information systems data for New York City supermarkets, fruit and vegetable markets, and farmers' markets and employed both kernel density and distance measures. We found that adjusting for vehicle ownership and crime tended to increase measured disparities in access to supermarkets by neighborhood race/ethnicity and income, while adjusting for public transit and traffic safety tended to narrow these disparities. Further, considering fruit and vegetable markets and farmers' markets, as well as supermarkets, increased the density of healthy food outlets, especially in neighborhoods with high concentrations of Hispanics, Asians, and foreign-born residents and in high-poverty neighborhoods. PMID:21117330

  11. Neighborhood Environments and Objectively Measured Physical Activity in 11 Countries

    PubMed Central

    Cerin, Ester; Cain, Kelli L; Conway, Terry L; Dyck, Delfien Van; Hinckson, Erica; Schipperijn, Jasper; Bourdeaudhuij, Ilse De; Owen, Neville; Davey, Rachel C; Hino, Adriano Akira Ferreira; Mitáš, Josef; Orzanco-Garralda, Rosario; Salvo, Deborah; Sarmiento, Olga L; Christiansen, Lars B; Macfarlane, Duncan J; Schofield, Grant; Sallis, James F

    2014-01-01

    Purpose Environmental changes are potentially effective population-level physical activity (PA) promotion strategies. However, robust multi-site evidence to guide international action for developing activity-supportive environments is lacking. We estimated pooled associations of perceived environmental attributes with objectively-measured PA outcomes; between-site differences in such associations; and, the extent to which perceived environmental attributes explain between-site differences in PA. Methods This was a cross-sectional study conducted in 16 cities located in Belgium, Brazil, Colombia, Czech Republic, Denmark, China, Mexico, New Zealand, Spain, United Kingdom, and USA. Participants were 6,968 adults residing in administrative units stratified by socio-economic status and transport-related walkability. Predictors were 10 perceived neighborhood environmental attributes. Outcome measures were accelerometry-assessed weekly minutes of moderate-to-vigorous PA (MVPA) and meeting the PA guidelines for cancer/weight gain prevention (420 min/week of MVPA). Results Most perceived neighborhood attributes were positively associated with the PA outcomes in the pooled, site-adjusted, single-predictor models. Associations were generalizable across geographical locations. Aesthetics and land use mix – access were significant predictors of both PA outcomes in the fully-adjusted models. Environmental attributes accounted for within-site variability in MVPA corresponding to a 3 min/d or 21 min/week standard deviation. Large between-site differences in PA outcomes were observed: 15.9% to 16.8% of these differences were explained by perceived environmental attributes. All neighborhood attributes were associated with between-site differences in the total effects of the perceived environment on PA outcomes. Conclusions Residents’ perceptions of neighborhood attributes that facilitate walking were positively associated with objectively-measured MVPA and meeting the guidelines

  12. Material Property Measurement in Hostile Environments using Laser Acoustics

    SciTech Connect

    Ken L. Telschow

    2004-08-01

    Acoustic methods are well known and have been used to measure various intrinsic material properties, such as, elastic coefficients, density, crystal axis orientation, microstructural texture, and residual stress. Extrinsic properties, such as, dimensions, motion variables or temperature are also readily determined from acoustic methods. Laser acoustics, employing optical generation and detection of elastic waves, has a unique advantage over other acoustic methods—it is noncontacting, uses the sample surface itself for transduction, requires no couplant or invasive sample surface preparation and can be utilized in any hostile environment allowing optical access to the sample surface. In addition, optical generation and detection probe beams can be focused to the micron scale and/or shaped to alter the transduction process with a degree of control not possible using contact transduction methods. Laser methods are amenable to both continuous wave and pulse-echo measurements and have been used from Hz to 100’s of GHz (time scales from sec to psec) and with amplitudes sufficient to fracture materials. This paper shall review recent applications of laser acoustic methods to determining material properties in hostile environments that preclude the use of contacting transduction techniques. Example environments include high temperature (>1000C) sintering and molten metal processing, thin film deposition by plasma techniques, materials moving at high velocity during the fabrication process and nuclear high radiation regions. Recent technological advances in solid-state lasers and telecommunications have greatly aided the development and implementation of laser acoustic methods, particularly at ultra high frequencies. Consequently, laser acoustic material property measurements exhibit high precision and reproducibility today. In addition, optical techniques provide methods of imaging acoustic motion that is both quantitative and rapid. Possible future directions for

  13. Use of Smoothed Measured Winds to Predict and Assess Launch Environments

    NASA Technical Reports Server (NTRS)

    Cordova, Henry S.; Leahy, Frank; Adelfang, Stanley; Roberts, Barry; Starr, Brett; Duffin, Paul; Pueri, Daniel

    2011-01-01

    Since many of the larger launch vehicles are operated near their design limits during the ascent phase of flight to optimize payload to orbit, it often becomes necessary to verify that the vehicle will remain within certification limits during the ascent phase as part of the go/no-go review made prior to launch. This paper describes the approach used to predict Ares I-X launch vehicle structural air loads and controllability prior to launch which represents a distinct departure from the methodology of the Space Shuttle and Evolved Expendable Launch Vehicle (EELV) programs. Protection for uncertainty of key environment and trajectory parameters is added to the nominal assessment of launch capability to ensure that critical launch trajectory variables would be within the integrated vehicle certification envelopes. This process was applied by the launch team as a key element of the launch day go/no-go recommendation. Pre-launch assessments of vehicle launch capability for NASA's Space Shuttle and the EELV heavy lift versions require the use of a high-resolution wind profile measurements, which have relatively small sample size compared with low-resolution profile databases (which include low-resolution balloons and radar wind profilers). The approach described in this paper has the potential to allow the pre-launch assessment team to use larger samples of wind measurements from low-resolution wind profile databases that will improve the accuracy of pre-launch assessments of launch availability with no degradation of mission assurance or launch safety.

  14. Martian Radiation Environment: Model Calculations and Recent Measurements with "MARIE"

    NASA Technical Reports Server (NTRS)

    Saganti, P. B.; Cucinotta, F. A.; zeitlin, C. J.; Cleghorn, T. F.

    2004-01-01

    The Galactic Cosmic Ray spectra in Mars orbit were generated with the recently expanded HZETRN (High Z and Energy Transport) and QMSFRG (Quantum Multiple-Scattering theory of nuclear Fragmentation) model calculations. These model calculations are compared with the first eighteen months of measured data from the MARIE (Martian Radiation Environment Experiment) instrument onboard the 2001 Mars Odyssey spacecraft that is currently in Martian orbit. The dose rates observed by the MARIE instrument are within 10% of the model calculated predictions. Model calculations are compared with the MARIE measurements of dose, dose-equivalent values, along with the available particle flux distribution. Model calculated particle flux includes GCR elemental composition of atomic number, Z = 1-28 and mass number, A = 1-58. Particle flux calculations specific for the current MARIE mapping period are reviewed and presented.

  15. Acoustic Environment of Admiralty Inlet: Broadband Noise Measurements

    SciTech Connect

    Xu, Jinshan; Deng, Zhiqun; Martinez, Jayson J.; Carlson, Thomas J.; Myers, Joshua R.; Weiland, Mark A.; Jones, Mark E.

    2011-09-30

    Admiralty Inlet has been selected as a potential tidal energy site. It is located near shipping lanes, is a highly variable acoustic environment, and is frequented by the highly endangered southern resident killer whale (SRKW). Resolving environmental impacts is the first step to receiving approval to deploy tidal turbines at Admiralty Inlet. Of particular concern is the potential for blade strike or other negative interactions between the SRKW and the tidal turbine. A variety of technologies including passive and active monitoring systems are being considered as potential tools to determine the presence of SRKW in the vicinity of the turbines. Broadband noise level measurements are critical for the determination of design and operation specifications of all marine and hydrokinetic energy capture technologies. Acoustic environment data at the proposed site was acquired at different depths using a cabled vertical line array (VLA) with four calibrated hydrophones. The sound pressure level (SPL) power spectrum density was estimated based on the fast Fourier transform. This study describes the first broadband SPL measurements for this site at different depths with frequency ranging from 10 kHz to 480 kHz in combination with other information. To understand the SPL caused by this bedload transport, three different pressure sensors with temperature and conductivity were also assembled on the VLA to measure the conditions at the hydrophone deployment depth. The broadband SPL levels at frequency ranges of 3 kHz to 7 kHz as a function of depth were estimated. Only the hydrophone at an average depth of 40 m showed the strong dependence of SPL with distance from the bottom, which was possibly caused by the cobbles shifting on the seabed. Automatic Identification System data were also studied to understand the SPL measurements.

  16. Measurement of participation: intersecting person, task, and environment.

    PubMed

    Mallinson, Trudy; Hammel, Joy

    2010-09-01

    The goals of this article are to describe participation as a transaction and issues involved in measuring and intervening using this transactional approach; describe ecologic and systems-based theoretic approaches for conceptualizing person-task-environment transactions; and illustrate examples of an exploratory strategy, radar plots, as a clinical tool for rehabilitation professionals to show this interaction and use it to inform participation-focused interventions with people with disabilities in rehabilitation settings. Participation necessarily occurs at the intersection of what the person can do, wants to do, has the opportunity to do, and is not prevented from doing. It is a transaction that occurs at the nexus of the person-task-environment. Measurement of participation should capture this transactive nature. Radar plots are part of a group of graphic displays frequently referred to as exploratory data analysis. In situations in which theory is not well developed, exploratory techniques such as radar plots may hold promise as ways to explore better the relationship among variables. This article describes strengths and limitations of radar plots and presents an example with data from the Community Participation Database. PMID:20801276

  17. Measured force on elongated bodies in a simulated low-Earth orbit environment

    SciTech Connect

    Maldonado, C. A.; Ketsdever, A. D.; Gimelshein, S. F.

    2014-12-09

    An overview of the development of a magnetically filtered atomic oxygen plasma source and the application of the source to study low-Earth orbit drag on elongated bodies is presented. Plasma diagnostics show that the magnetic filter plasma source produces atomic oxygen ions (O{sup +}) with streaming energies equivalent to the relative orbital environment of approximately 5eV and can supply the appropriate density for LEO simulation. Previous research has demonstrated that momentum transfer between ions and metal surfaces is equivalent to the momentum transfer expected for neutral molecules with similar energy, due to charge exchange occurring prior to momentum transfer. Total drag measurements of aluminum cuboid geometries of varying length to diameter ratios immersed in the extracted plasma plume are presented as a function of streaming ion energy.

  18. Measured force on elongated bodies in a simulated low-Earth orbit environment

    NASA Astrophysics Data System (ADS)

    Maldonado, C. A.; Ketsdever, A. D.; Gimelshein, S. F.

    2014-12-01

    An overview of the development of a magnetically filtered atomic oxygen plasma source and the application of the source to study low-Earth orbit drag on elongated bodies is presented. Plasma diagnostics show that the magnetic filter plasma source produces atomic oxygen ions (O+) with streaming energies equivalent to the relative orbital environment of approximately 5eV and can supply the appropriate density for LEO simulation. Previous research has demonstrated that momentum transfer between ions and metal surfaces is equivalent to the momentum transfer expected for neutral molecules with similar energy, due to charge exchange occurring prior to momentum transfer. Total drag measurements of aluminum cuboid geometries of varying length to diameter ratios immersed in the extracted plasma plume are presented as a function of streaming ion energy.

  19. A Participatory Approach to the Identification of Measures of Number Sense in Children Prior to School Entry

    ERIC Educational Resources Information Center

    Howell, Sally; Kemp, Coral

    2009-01-01

    The research reported in this paper used a modified Delphi procedure in an attempt to establish a consensus on tasks proposed to assess components of number sense identified as essential for early mathematics success by a broad range of academics with expertise in the area of early mathematics. Tasks included as measures of these components were…

  20. Effects of Armodafinil on Simulated Driving and Self-Report Measures in Obstructive Sleep Apnea Patients prior to Treatment with Continuous Positive Airway Pressure

    PubMed Central

    Kay, Gary G.; Feldman, Neil

    2013-01-01

    Study Objectives: Obstructive sleep apnea (OSA) has been associated with an increased risk of motor vehicle crashes. This driving risk can be reduced (≥ 50%) by treatment with continuous positive airway pressure (CPAP). However residual excessive daytime sleepiness (EDS) can persist for some patients who regularly use CPAP. The current study was designed to assess the effect of armodafinil on simulated driving performance and subsequent CPAP treatment compliance in newly diagnosed OSA patients with EDS during a 2-week “waiting period” prior to initiation of CPAP. Methods: Sixty-nine newly diagnosed OSA patients, awaiting CPAP therapy, were randomized (1:1) to placebo or armodafinil (150 mg/day) treatment. Simulated driving tests and self-report measures were completed at baseline, after 2 weeks of drug treatment, and following 6 weeks of CPAP treatment. CPAP compliance was evaluated at the end of 6 weeks of CPAP. Results: Compared to placebo, armodafinil improved simulated driving safety performance in OSA patients awaiting CPAP therapy (p = 0.03). Improvement was seen in lane position deviation (p = 0.002) and number of lane excursions (p = 0.02). Improvement was also observed on measures of sleepiness using the Epworth Sleepiness Scale (ESS) and sleep related quality of life. Following 6 weeks of CPAP, there was also significant improvement observed on multiple measures of simulated driving performance. CPAP compliance did not differ between armodafinil-treated and placebo-treated patients (p = 0.80). Conclusions: Armodafinil was found to improve simulated driving performance in OSA patients with EDS prior to initiation of CPAP. Treatment with armodafinil showed no effect on subsequent CPAP compliance. Citation: Kay GG; Feldman N. Effects of armodafinil on simulated driving and self-report measures in obstructive sleep apnea patients prior to treatment with continuous positive airway pressure. J Clin Sleep Med 2013;9(5):445-454. PMID:23674935

  1. Description, measurement and evaluation of tertiary-education food environments.

    PubMed

    Roy, R; Hebden, L; Kelly, B; De Gois, T; Ferrone, E M; Samrout, M; Vermont, S; Allman-Farinelli, M

    2016-05-01

    Obesity in young adults is an increasing health problem in Australia and many other countries. Evidence-based information is needed to guide interventions that reduce the obesity-promoting elements in tertiary-education environments. In a food environmental audit survey, 252 outlets were audited across seven institutions: three universities and four technical and further education institutions campuses. A scoring instrument called the food environment-quality index was developed and used to assess all food outlets on these campuses. Information was collated on the availability, accessibility and promotion of foods and beverages and a composite score (maximum score=148; higher score indicates healthier outlets) was calculated. Each outlet and the overall campus were ranked into tertiles based on their 'healthiness'. Differences in median scores for each outcome measure were compared between institutions and outlet types using one-way ANOVA with post hoc Scheffe's testing, χ 2 tests, Kruskal-Wallis H test and the Mann-Whitney U test. Binomial logistic regressions were used to compare the proportion of healthy v. unhealthy food categories across different types of outlets. Overall, the most frequently available items were sugar-sweetened beverages (20 % of all food/drink items) followed by chocolates (12 %), high-energy (>600 kJ/serve) foods (10 %), chips (10 %) and confectionery (10 %). Healthy food and beverages were observed to be less available, accessible and promoted than unhealthy options. The median score across all outlets was 72 (interquartile range=7). Tertiary-education food environments are dominated by high-energy, nutrient-poor foods and beverages. Interventions to decrease availability, accessibility and promotion of unhealthy foods are needed. PMID:27245102

  2. Mars Environment and Magnetic Orbiter Scientific and Measurement Objectives

    NASA Astrophysics Data System (ADS)

    Leblanc, F.; Langlais, B.; Fouchet, T.; Barabash, S.; Breuer, D.; Chassefière, E.; Coates, A.; Dehant, V.; Forget, F.; Lammer, H.; Lewis, S.; Lopez-Valverde, M.; Mandea, M.; Menvielle, M.; Pais, A.; Paetzold, M.; Read, P.; Sotin, C.; Tarits, P.; Vennerstrom, S.

    2009-02-01

    In this paper, we summarize our present understanding of Mars' atmosphere, magnetic field, and surface and address past evolution of these features. Key scientific questions concerning Mars' surface, atmosphere, and magnetic field, along with the planet's interaction with solar wind, are discussed. We also define what key parameters and measurements should be performed and the main characteristics of a martian mission that would help to provide answers to these questions. Such a mission -- Mars Environment and Magnetic Orbiter (MEMO) -- was proposed as an answer to the Cosmic Vision Call of Opportunity as an M-class mission (corresponding to a total European Space Agency cost of less than 300 M€). MEMO was designed to study the strong interconnection between the planetary interior, atmosphere, and solar conditions, which is essential to our understanding of planetary evolution, the appearance of life, and its sustainability. The MEMO main platform combined remote sensing and in situ measurements of the atmosphere and the magnetic field during regular incursions into the martian upper atmosphere. The micro-satellite was designed to perform simultaneous in situ solar wind measurements. MEMO was defined to conduct: • Four-dimensional mapping of the martian atmosphere from the surface up to 120 km by measuring wind, temperature, water, and composition, all of which would provide a complete view of the martian climate and photochemical system; • Mapping of the low-altitude magnetic field with unprecedented geographical, altitude, local time, and seasonal resolutions; • A characterization of the simultaneous responses of the atmosphere, magnetic field, and near-Mars space to solar variability by means of in situ atmospheric and solar wind measurements.

  3. Aldehyde measurements in indoor environments in Strasbourg (France)

    NASA Astrophysics Data System (ADS)

    Marchand, C.; Bulliot, B.; Le Calvé, S.; Mirabel, Ph.

    Formaldehyde and acetaldehyde concentrations have been measured in indoor environments of various public spaces (railway station, airport, shopping center, libraries, underground parking garage, etc.) of Strasbourg area (east of France). In addition, formaldehyde, acetaldehyde propionaldehyde and hexanal concentrations have been measured in 22 private homes in the same area. In most of the sampling sites, indoor and outdoor formaldehyde and acetaldehyde concentrations were measured simultaneously. Gaseous aldehydes levels were quantified by a conventional DNHP-derivatization method followed by liquid chromatography coupled to UV detection. Outdoor formaldehyde and acetaldehyde concentrations were both in the range 1-10 μg m -3, the highest values being measured at the airport and railway station. Indoor concentrations were strongly dependant upon the sampling sites. In homes, the average concentrations were 37 μg m -3 (living rooms) and 46 μg m -3 (bedrooms) for formaldehyde, 15 μg m -3 (living rooms) and 18 μg m -3 (bedrooms) for acetaldehyde, 1.2 μg m -3 (living rooms) and 1.6 μg m -3 (bedrooms) for propionaldehyde, 9 μg m -3 (living rooms) and 10 μg m -3 (bedrooms) for hexanal. However, concentrations as high as 123, 80 and 47 μg m -3 have been found for formaldehyde, acetaldehyde and hexanal respectively. In public spaces, the highest formaldehyde concentration (62 μg m -3) was found in a library and the highest concentration of acetaldehyde (26 μg m -3) in the hall of a shopping center. Additional measurements of formaldehyde and acetaldehyde were made inside a car both at rest or in a fluid or heavy traffic as well as in a room where cigarettes were smoked. Our data have been discussed and compared with those of previous studies.

  4. Mars environment and magnetic orbiter scientific and measurement objectives.

    PubMed

    Leblanc, F; Langlais, B; Fouchet, T; Barabash, S; Breuer, D; Chassefière, E; Coates, A; Dehant, V; Forget, F; Lammer, H; Lewis, S; Lopez-Valverde, M; Mandea, M; Menvielle, M; Pais, A; Paetzold, M; Read, P; Sotin, C; Tarits, P; Vennerstrom, S

    2009-01-01

    In this paper, we summarize our present understanding of Mars' atmosphere, magnetic field, and surface and address past evolution of these features. Key scientific questions concerning Mars' surface, atmosphere, and magnetic field, along with the planet's interaction with solar wind, are discussed. We also define what key parameters and measurements should be performed and the main characteristics of a martian mission that would help to provide answers to these questions. Such a mission--Mars Environment and Magnetic Orbiter (MEMO)--was proposed as an answer to the Cosmic Vision Call of Opportunity as an M-class mission (corresponding to a total European Space Agency cost of less than 300 Meuro). MEMO was designed to study the strong interconnection between the planetary interior, atmosphere, and solar conditions, which is essential to our understanding of planetary evolution, the appearance of life, and its sustainability. The MEMO main platform combined remote sensing and in situ measurements of the atmosphere and the magnetic field during regular incursions into the martian upper atmosphere. The micro-satellite was designed to perform simultaneous in situ solar wind measurements. MEMO was defined to conduct: * Four-dimensional mapping of the martian atmosphere from the surface up to 120 km by measuring wind, temperature, water, and composition, all of which would provide a complete view of the martian climate and photochemical system; Mapping of the low-altitude magnetic field with unprecedented geographical, altitude, local time, and seasonal resolutions; A characterization of the simultaneous responses of the atmosphere, magnetic field, and near-Mars space to solar variability by means of in situ atmospheric and solar wind measurements. PMID:19317625

  5. X ray based displacement measurement for hostile environments

    NASA Technical Reports Server (NTRS)

    Canistraro, Howard A.; Jordon, Eric H.; Pease, Douglas M.; Fralick, Gustave C.

    1992-01-01

    A new method on noncontacting, high temperature extensometry based on the focus and scanning of x rays is currently under development and shows great promise of overcoming limitations associated with available techniques. The chief advantage is the ability to make undisturbed measurements through stratified or flowing gases, smoke, and flame. The system is based on the ability to focus and scan low energy, hard x rays such as those emanating from copper or molybdenum sources. The x rays are focused into a narrow and intense line image which can be scanned onto targets that fluoresce secondary x ray radiation. The final goal of the system is the ability to conduct macroscopic strain measurements in hostile environments by utilizing two or more fluorescing targets. Current work is limited to displacement measurement of a single target with a resolution of 1.25 micro-m and a target temperature of 1200 C, directly through an open flame. The main advantage of the technique lies in the penetrating nature of x rays which are not affected by the presence of refracting gas layers, smoke, flame, or intense thermal radiation, all of which could render conventional extensometry methods inoperative or greatly compromise their performance.

  6. X-ray-based displacement measurement for hostile environments

    NASA Technical Reports Server (NTRS)

    Canistraro, H. A.; Jordan, E. H.; Pease, D. M.

    1992-01-01

    A new method on noncontacting, high temperature extensometry based on the focus and scanning of X-rays is currently under development and shows great promise of overcoming limitations associated with available techniques. The chief advantage is the ability to make undisturbed measurements through stratified or flowing gases, smoke, and flame. The system is based on the ability to focus and scan low energy, hard X-rays such as those emanating from copper or molybdenum sources. The X-rays are focused into a narrow and intense line image which can be scanned onto targets that fluoresce secondary X-ray radiation. The final goal of the system is the ability to conduct macroscopic strain measurements in hostile environments by utilizing two or more fluorescing targets. Current work is limited to displacement measurement of a single target with a resolution of 1.25 micro-m and a target temperature of 1200 C, directly through an open flame. The main advantage of the technique lies in the penetrating nature of X-rays which are not affected by the presence of refracting gas layers, smoke, flame, or intense thermal radiation, all of which could render conventional extensometry methods inoperative or greatly compromise their performance.

  7. Beam Shaping for CARS Measurements in Turbulent Environments

    NASA Technical Reports Server (NTRS)

    Magnotti, Gaetano; Cutler, Andrew D.; Danehy, Paul M.

    2010-01-01

    This paper describes a new technique to mitigate the effect of beam steering on CARS measurements in turbulent, variable density environments. The new approach combines Planar BOXCARS phase-matching with elliptical shaping of one of the beams to generate a signal insensitive to beam steering, while keeping the same spatial resolution. Numerical and experimental results are provided to demonstrate the effectiveness of this approach. One set of experiments investigated the effect of beam shaping in the presence of a controlled and well quantified displacement of the beams at the focal plane. Another set of experiments, more qualitative, proved the effectiveness of the technique in the presence of severe beam steering due to turbulence.

  8. Measuring the 'obesogenic' food environment in New Zealand primary schools.

    PubMed

    Carter, Mary-Ann; Swinburn, Boyd

    2004-03-01

    Childhood obesity is an increasing health problem in New Zealand and many other countries. Information is needed to guide interventions that reduce the 'obesogenic' (obesity-promoting) elements of school environments. The aim of this study was to identify and measure the obesogenic elements of the school environment and the canteen sales of energy-dense foods and drinks. A self-completion questionnaire was developed for assessing each school's nutrition environment and mailed to a stratified random sample of New Zealand schools. The responses from primary schools (n = 200, response rate 61%) were analysed. Only 15.5% of schools had purpose-built canteen facilities and over half ran a food service for profit (31% profit to the school, 24.5% profit for the contractors). Only 16.5% of schools had a food policy, although 91% of those rated the policy as effective or very effective. The most commonly available foods for sale were pies (79%), juice (57%) and sausage rolls (54.5%). Filled rolls were the most expensive item (mean dollars 1.79) and fruit the least expensive (mean dollars 0.47). The ratio of 'less healthy' to 'more healthy' main choices was 5.6:1, for snacks it was 9.3:1 and for drinks it was 1.4:1. In contrast, approximately 60% of respondents said that nutrition was a priority for the school. Only 50% felt there was management support for healthy food choices and only 39% agreed that mainly nutritious food was offered by the food service. 'Less healthy' choices dominated food sales by more than 2:1, with pies being the top selling item (>55000 per week). We found that the food environment was not conducive to healthy food choices for the children at New Zealand schools and that this was reflected in the high sales of relatively unhealthy foods from the school food services. Programmes that improve school food through policies, availability, prices and school ethos are urgently needed. PMID:14976168

  9. Measuring the Interestingness of Articles in a Limited User Environment

    SciTech Connect

    Pon, R; Cardenas, A; Buttler, David; Critchlow, Terence J

    2011-01-01

    Search engines, such as Google, assign scores to news articles based on their relevance to a query. However, not all relevant articles for the query may be interesting to a user. For example, if the article is old or yields little new information, the article would be uninteresting. Relevance scores do not take into account what makes an article interesting, which would vary from user to user. Although methods such as collaborative filtering have been shown to be effective in recommendation systems, in a limited user environment, there are not enough users that would make collaborative filtering effective. A general framework, called iScore, is presented for defining and measuring the ‘‘interestingness of articles, incorporating user-feedback. iScore addresses the various aspects of what makes an article interesting, such as topic relevance, uniqueness, freshness, source reputation, and writing style. It employs various methods, such as multiple topic tracking, online parameter selection, language models, clustering, sentiment analysis, and phrase extraction to measure these features. Due to varying reasons that users hold about why an article is interesting, an online feature selection method in naι¨ve Bayes is also used to improve recommendation results. iScore can outperform traditional IR techniques by as much as 50.7%. iScore and its components are evaluated in the news recommendation task using three datasets from Yahoo! News, actual users, and Digg.

  10. Measurement realities of current collection in dynamic space plasma environments

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, Edward P.

    1990-01-01

    Theories which describe currents collected by conducting and non-conducting bodies immersed in plasmas have many of their concepts based upon the fundamentals of sheath-potential distributions and charged-particle behavior in superimposed electric and magnetic fields. Those current-collecting bodies (or electrodes) may be Langmuir probes, electric field detectors, aperture plates on ion mass spectrometers and retarding potential analyzers, or spacecraft and their rigid and tethered appendages. Often the models are incomplete in representing the conditions under which the current-voltage characteristics of the electrode and its system are to be measured. In such cases, the experimenter must carefully take into account magnetic field effects and particle anisotropies, perturbations caused by the current collection process itself and contamination on electrode surfaces, the complexities of non-Maxwellian plasma distributions, and the temporal variability of the local plasma density, temperature, composition and fields. This set of variables is by no means all-inclusive, but it represents a collection of circumstances guaranteed to accompany experiments involving energetic particle beams, plasma discharges, chemical releases, wave injection and various events of controlled and uncontrolled spacecraft charging. Here, an attempt is made to synopsize these diagnostic challenges and frame them within a perspective that focuses on the physics under investigation and the requirements on the parameters to be measured. Examples include laboratory and spaceborne applications, with specific interest in dynamic and unstable plasma environments.

  11. Parallel strip waveguide for ultrasonic flow measurement in harsh environments.

    PubMed

    Laws, Michael; Ramadas, Sivaram N; Lynnworth, Lawrence C; Dixon, Steve

    2015-04-01

    Wetted ultrasonic transit time flow meters typically consist of one or more pairs of transducers, containing piezoelectric elements, which alternate between transmitting and detecting an ultrasonic pulse. Typical piezoelectric materials and the adhesives used to attach the piezoelectric element in such devices can be damaged by hostile environments, such as extreme temperature, potentially limiting possible applications of ultrasonic flow measurement techniques. We have investigated a design for a flow meter with an integrated thermal buffer waveguide consisting of five parallel stainless steel strips. These, in addition to thermal protection, may function as a transducer array, with the possibility of steering the emitted field. Because the buffer strips used in the transducer assembly are thin, one might expect Lamb-like guided waves to propagate along it. However, the finite width of the strips has a significant effect on the propagation characteristics of the guided waves. In this work, the effect of the waveguide's small rectangular cross-section has been studied. Additionally, we have examined the effect of thermal gradients on the average sound speed and dispersion characteristics of such strip waveguides. We also suggest modifications to the plate geometry, which can alter both the frequency content and the shape of the transmitted pulse, potentially giving a better signal to use in flow measurement. PMID:25881347

  12. Rasch Measurement of Collaborative Problem Solving in an Online Environment.

    PubMed

    Harding, Susan-Marie E; Griffin, Patrick E

    2016-01-01

    This paper describes an approach to the assessment of human to human collaborative problem solving using a set of online interactive tasks completed by student dyads. Within the dyad, roles were nominated as either A or B and students selected their own roles. The question as to whether role selection affected individual student performance measures is addressed. Process stream data was captured from 3402 students in six countries who explored the problem space by clicking, dragging the mouse, moving the cursor and collaborating with their partner through a chat box window. Process stream data were explored to identify behavioural indicators that represented elements of a conceptual framework. These indicative behaviours were coded into a series of dichotomous items. These items represented actions and chats performed by students. The frequency of occurrence was used as a proxy measure of item difficulty. Then given a measure of item difficulty, student ability could be estimated using the difficulty estimates of the range of items demonstrated by the student. The Rasch simple logistic model was used to review the indicators to identify those that were consistent with the assumptions of the model and were invariant across national samples, language, curriculum and age of the student. The data were analysed using a one and two dimension, one parameter model. Rasch separation reliability, fit to the model, distribution of students and items on the underpinning construct, estimates for each country and the effect of role differences are reported. This study provides evidence that collaborative problem solving can be assessed in an online environment involving human to human interaction using behavioural indicators shown to have a consistent relationship between the estimate of student ability, and the probability of demonstrating the behaviour. PMID:26784377

  13. Air Traffic Complexity Measurement Environment (ACME): Software User's Guide

    NASA Technical Reports Server (NTRS)

    1996-01-01

    A user's guide for the Air Traffic Complexity Measurement Environment (ACME) software is presented. The ACME consists of two major components, a complexity analysis tool and user interface. The Complexity Analysis Tool (CAT) analyzes complexity off-line, producing data files which may be examined interactively via the Complexity Data Analysis Tool (CDAT). The Complexity Analysis Tool is composed of three independently executing processes that communicate via PVM (Parallel Virtual Machine) and Unix sockets. The Runtime Data Management and Control process (RUNDMC) extracts flight plan and track information from a SAR input file, and sends the information to GARP (Generate Aircraft Routes Process) and CAT (Complexity Analysis Task). GARP in turn generates aircraft trajectories, which are utilized by CAT to calculate sector complexity. CAT writes flight plan, track and complexity data to an output file, which can be examined interactively. The Complexity Data Analysis Tool (CDAT) provides an interactive graphic environment for examining the complexity data produced by the Complexity Analysis Tool (CAT). CDAT can also play back track data extracted from System Analysis Recording (SAR) tapes. The CDAT user interface consists of a primary window, a controls window, and miscellaneous pop-ups. Aircraft track and position data is displayed in the main viewing area of the primary window. The controls window contains miscellaneous control and display items. Complexity data is displayed in pop-up windows. CDAT plays back sector complexity and aircraft track and position data as a function of time. Controls are provided to start and stop playback, adjust the playback rate, and reposition the display to a specified time.

  14. An equal start: absence of group differences in cognitive, social, and neural measures prior to music or sports training in children

    PubMed Central

    Habibi, Assal; Ilari, Beatriz; Crimi, Kevin; Metke, Michael; Kaplan, Jonas T.; Joshi, Anand A.; Leahy, Richard M.; Shattuck, David W.; Choi, So Y.; Haldar, Justin P.; Ficek, Bronte; Damasio, Antonio; Damasio, Hanna

    2014-01-01

    Several studies comparing adult musicians and non-musicians have provided compelling evidence for functional and anatomical differences in the brain systems engaged by musical training. It is not known, however, whether those differences result from long-term musical training or from pre-existing traits favoring musicality. In an attempt to begin addressing this question, we have launched a longitudinal investigation of the effects of childhood music training on cognitive, social and neural development. We compared a group of 6- to 7-year old children at the start of intense after-school musical training, with two groups of children: one involved in high intensity sports training but not musical training, another not involved in any systematic training. All children were tested with a comprehensive battery of cognitive, motor, musical, emotional, and social assessments and underwent magnetic resonance imaging and electroencephalography. Our first objective was to determine whether children who participate in musical training were different, prior to training, from children in the control groups in terms of cognitive, motor, musical, emotional, and social behavior measures as well as in structural and functional brain measures. Our second objective was to determine whether musical skills, as measured by a music perception assessment prior to training, correlates with emotional and social outcome measures that have been shown to be associated with musical training. We found no neural, cognitive, motor, emotional, or social differences among the three groups. In addition, there was no correlation between music perception skills and any of the social or emotional measures. These results provide a baseline for an ongoing longitudinal investigation of the effects of music training. PMID:25249961

  15. An equal start: absence of group differences in cognitive, social, and neural measures prior to music or sports training in children.

    PubMed

    Habibi, Assal; Ilari, Beatriz; Crimi, Kevin; Metke, Michael; Kaplan, Jonas T; Joshi, Anand A; Leahy, Richard M; Shattuck, David W; Choi, So Y; Haldar, Justin P; Ficek, Bronte; Damasio, Antonio; Damasio, Hanna

    2014-01-01

    Several studies comparing adult musicians and non-musicians have provided compelling evidence for functional and anatomical differences in the brain systems engaged by musical training. It is not known, however, whether those differences result from long-term musical training or from pre-existing traits favoring musicality. In an attempt to begin addressing this question, we have launched a longitudinal investigation of the effects of childhood music training on cognitive, social and neural development. We compared a group of 6- to 7-year old children at the start of intense after-school musical training, with two groups of children: one involved in high intensity sports training but not musical training, another not involved in any systematic training. All children were tested with a comprehensive battery of cognitive, motor, musical, emotional, and social assessments and underwent magnetic resonance imaging and electroencephalography. Our first objective was to determine whether children who participate in musical training were different, prior to training, from children in the control groups in terms of cognitive, motor, musical, emotional, and social behavior measures as well as in structural and functional brain measures. Our second objective was to determine whether musical skills, as measured by a music perception assessment prior to training, correlates with emotional and social outcome measures that have been shown to be associated with musical training. We found no neural, cognitive, motor, emotional, or social differences among the three groups. In addition, there was no correlation between music perception skills and any of the social or emotional measures. These results provide a baseline for an ongoing longitudinal investigation of the effects of music training. PMID:25249961

  16. Space environment measurements by JAXA satellites and ISS/JEM

    NASA Astrophysics Data System (ADS)

    Obara, Takahiro; Matsumoto, Haruhisa; Koga, Kiyokazu

    2012-02-01

    In order to monitor space environment and its temporal variations, JAXA Space Environment Group has been developing space radiation detectors as well as magnetometers and installing them on Low Earth Orbit (LEO) satellites, Geostationary Orbit (GEO) satellites, Geostationary Transfer Orbit (GTO) satellite, Quasi Zenith Orbit (QZO) satellite and Japanese Experimental Module (JEM) of the International Space Station (ISS). We are using these space environment data to know the situation of space environment and to provide warning messages to the satellite operators as well as ISS/JEM manager, when the space environment will be harmful. Based on our observation data, we also have constructed an advanced electron belt model for the use in satellite manufacturing. With space radiation data obtained by JAXA satellites and ISS, some findings related to the space radiation environment have been obtained. We will review our activities related to the space environment research and development in JAXA.

  17. Measurements of the thermal plasma environment of the space shuttle

    NASA Astrophysics Data System (ADS)

    Raitt, W. J.; Siskind, D. E.; Banks, P. M.; Williamson, P. R.

    1984-04-01

    The paper presents some initial results on measurements of the thermal plasma environment obtained by a spherical retarding potential analyzer and a Langmuir probe flown on the third space shuttle flight ( STS-3) as part of the NASA Office of Space Science-1 (OSS-1) payload in March 1982. One of the major effects observed is a higher degree of turbulence in the ambient plasma compared to what is observed from similar instruments flown on unmanned satellites. In addition we see the temperature of the thermal electrons elevated to values of 4000-5000 K. Associated with elevated electron temperatures are regions of enhanced plasma density resulting from the appearance of high densities of molecular ions. The thermal plasma data also show clear effects of an induced V × B · L potential at the location of the probes which matches that produced by an L vector linking the probes to the engine nozzles; thereby establishing the prime return current location on the Orbiter. The final observations discussed are the pronounced and complex wake effects resulting both from the main structure of the Orbiter and from the complex shapes of appendages attached to the Orbiter.

  18. Measuring the Interestingness of Articles in a Limited User Environment

    SciTech Connect

    Pon, Raymond K.

    2008-01-01

    Search engines, such as Google, assign scores to news articles based on their relevancy to a query. However, not all relevant articles for the query may be interesting to a user. For example, if the article is old or yields little new information, the article would be uninteresting. Relevancy scores do not take into account what makes an article interesting, which varies from user to user. Although methods such as collaborative filtering have been shown to be effective in recommendation systems, in a limited user environment, there are not enough users that would make collaborative filtering effective. A general framework, called iScore, is presented for defining and measuring the 'interestingness' of articles, incorporating user-feedback. iScore addresses various aspects of what makes an article interesting, such as topic relevancy, uniqueness, freshness, source reputation, and writing style. It employs various methods to measure these features and uses a classifier operating on these features to recommend articles. The basic iScore configuration is shown to improve recommendation results by as much as 20%. In addition to the basic iScore features, additional features are presented to address the deficiencies of existing feature extractors, such as one that tracks multiple topics, called MTT, and a version of the Rocchio algorithm that learns its parameters online as it processes documents, called eRocchio. The inclusion of both MTT and eRocchio into iScore is shown to improve iScore recommendation results by as much as 3.1% and 5.6%, respectively. Additionally, in TREC11 Adaptive Filter Task, eRocchio is shown to be 10% better than the best filter in the last run of the task. In addition to these two major topic relevancy measures, other features are also introduced that employ language models, phrases, clustering, and changes in topics to improve recommendation results. These additional features are shown to improve recommendation results by iScore by up to 14

  19. The Influence of Children's Prior Knowledge and Previous Experience on Their Spatial Orientation Skills in an Urban Environment

    ERIC Educational Resources Information Center

    Hemmer, Ingrid; Hemmer, Michael; Neidhardt, Eva; Obermaier, Gabriele; Uphues, Rainer; Wrenger, Katja

    2015-01-01

    This study investigates the capacity of children to develop map-based skills in spatial orientation in an urban environment unknown to them. In this quantitative study, a total of 328 pupils of grades 3-5 had to achieve specific skills with regard to map-based skills in spatial orientation (such as turning-off skills, transformation from map to…

  20. The Counseling Training Environment Scale (CTES): Development of a Self-Report Measure to Assess Counseling Training Environment

    ERIC Educational Resources Information Center

    Lau, Jared Miki Jun Kong

    2012-01-01

    Based on Bronfenbrenner's (1979, 1992) ecological framework, the Counseling Training Environment Scale (CTES) was developed as a self-report measure that assesses the learning and training environment of counseling and related mental health training programs as perceived by current students. A two-phase mixed-methods design was used to create…

  1. Measuring Perceived Sociability of Computer-Supported Collaborative Learning Environments

    ERIC Educational Resources Information Center

    Kreijns, Karel; Kirschner, Paul A.; Jochems, Wim; van Buuren, Hans

    2007-01-01

    Most asynchronous computer-supported collaborative learning (CSCL) environments can be characterized as "functional" environments because they focus on functional, task-specific support, often disregarding explicit support for the social (emotional) aspects of learning in groups which are acknowledged by many educational researchers to be…

  2. Effective method of measuring the radioactivity of [131I]-capsule prior to radioiodine therapy with significant reduction of the radiation exposure to the medical staff.

    PubMed

    Lützen, Ulf; Zhao, Yi; Marx, Malies; Imme, Thea; Assam, Isong; Siebert, Frank-Andre; Culman, Juaraj; Zuhayra, Maaz

    2016-01-01

    Radiation Protection in Radiology, Nuclear Medicine and Radio Oncology is of the utmost importance. Radioiodine therapy is a frequently used and effective method for the treatment of thyroid disease. Prior to each therapy the radioactivity of the [131I]-capsule must be determined to prevent misadministration. This leads to a significant radiation exposure to the staff. We describe an alternative method, allowing a considerable reduction of the radiation exposure. Two [131I]-capsules (A01 = 2818.5; A02 = 7355.0 MBq) were measured multiple times in their own delivery lead containers - that is to say, [131I]-capsules remain inside the containers during the measurements (shielded measurement) using a dose calibrator and a well-type and a thyroid uptake probe. The results of the shielded measurements were correlated linearly with the [131I]-capsules radioactivity to create calibration curves for the used devices. Additional radioactivity measurements of 50 [131I]-capsules of different radioactivities were done to validate the shielded measuring method. The personal skin dose rate (HP(0.07)) was determined using calibrated thermo luminescent dosimeters. The determination coefficients for the calibration curves were R2 > 0.9980 for all devices. The relative uncertainty of the shielded measurement was < 6.8%. At a distance of 10 cm from the unshielded capsule the HP(0.07) was 46.18 μSv/(GBq•s), and on the surface of the lead container containing the [131I]-capsule the HP(0.07) was 2.99 and 0.27 μSv/(GBq•s) for the two used container sizes. The calculated reduction of the effective dose by using the shielded measuring method was, depending on the used container size, 74.0% and 97.4%, compared to the measurement of the unshielded [131I]-capsule using a dose calibrator. The measured reduction of the effective radiation dose in the practice was 56.6% and 94.9 for size I and size II containers. The shielded [131I]-capsule measurement reduces the radiation exposure to the

  3. Measuring personal heat exposure in an urban and rural environment.

    PubMed

    Bernhard, Molly C; Kent, Shia T; Sloan, Meagan E; Evans, Mary B; McClure, Leslie A; Gohlke, Julia M

    2015-02-01

    Previous studies have linked heat waves to adverse health outcomes using ambient temperature as a proxy for estimating exposure. The goal of the present study was to test a method for determining personal heat exposure. An occupationally exposed group (urban groundskeepers in Birmingham, AL, USA N=21), as well as urban and rural community members from Birmingham, AL (N=30) or west central AL (N=30) wore data logging temperature and light monitors clipped to the shoe for 7 days during the summer of 2012. We found that a temperature monitor clipped to the shoe provided a comfortable and feasible method for recording personal heat exposure. Ambient temperature (°C) recorded at the nearest weather station was significantly associated with personal heat exposure [β 0.37, 95%CI (0.35, 0.39)], particularly in groundskeepers who spent more of their total time outdoors [β 0.42, 95%CI (0.39, 0.46)]. Factors significantly associated with lower personal heat exposure include reported time indoors [β -2.02, 95%CI (-2.15, -1.89)], reported income>20K [β -1.05, 95%CI (-1.79, -0.30)], and measured % body fat [β -0.07, 95%CI (-0.12, -0.02)]. There were significant associations between income and % body fat with lower indoor and nighttime exposures, but not with outdoor heat exposure, suggesting modifications of the home thermal environment play an important role in determining overall heat exposure. Further delineation of the effect of personal characteristics on heat exposure may help to develop targeted strategies for preventing heat-related illness. PMID:25617601

  4. Measuring personal heat exposure in an urban and rural environment

    PubMed Central

    Bernhard, Molly C; Kent, Shia T; Sloan, Meagan E; Evans, Mary B; McClure, Leslie A; Gohlke, Julia M

    2014-01-01

    Previous studies have linked heat waves to adverse health outcomes using ambient temperature as a proxy for estimating exposure. The goal of the present study was to test a method for determining personal heat exposure. An occupationally exposed group (urban groundskeepers in Birmingham, AL, USA N=21), as well as urban and rural community members from Birmingham, AL (N=30) or west central AL (N=30) wore data logging temperature and light monitors clipped to the shoe for 7 days during the summer of 2012. We found that a temperature monitor clipped to the shoe provided a comfortable and feasible method for recording personal heat exposure. Ambient temperature (°C) recorded at the nearest weather station was significantly associated with personal heat exposure [β 0.37, 95%CI (0.35, 0.39)], particularly in groundskeepers who spent more of their total time outdoors [β 0.42, 95%CI (0.39, 0.46)]. Factors significantly associated with lower personal heat exposure include reported time indoors [β −2.02, 95%CI (−2.15, −1.89)], reported income > 20K [β −1.05, 95%CI (−1.79, −0.30)], and measured % body fat [β −0.07, 95%CI (−0.12, −0.02)]. There were significant associations between income and % body fat with lower indoor and nighttime exposures, but not with outdoor heat exposure, suggesting modifications of the home thermal environment play an important role in determining overall heat exposure. Further delineation of the effect of personal characteristics on heat exposure may help to develop targeted strategies for preventing heat-related illness. PMID:25617601

  5. Characterization and quantification of intact 26S proteasome proteins by real-time measurement of intrinsic fluorescence prior to top-down mass spectrometry.

    PubMed

    Russell, Jason D; Scalf, Mark; Book, Adam J; Ladror, Daniel T; Vierstra, Richard D; Smith, Lloyd M; Coon, Joshua J

    2013-01-01

    Quantification of gas-phase intact protein ions by mass spectrometry (MS) is impeded by highly-variable ionization, ion transmission, and ion detection efficiencies. Therefore, quantification of proteins using MS-associated techniques is almost exclusively done after proteolysis where peptides serve as proxies for estimating protein abundance. Advances in instrumentation, protein separations, and informatics have made large-scale sequencing of intact proteins using top-down proteomics accessible to the proteomics community; yet quantification of proteins using a top-down workflow has largely been unaddressed. Here we describe a label-free approach to determine the abundance of intact proteins separated by nanoflow liquid chromatography prior to MS analysis by using solution-phase measurements of ultraviolet light-induced intrinsic fluorescence (UV-IF). UV-IF is measured directly at the electrospray interface just prior to the capillary exit where proteins containing at least one tryptophan residue are readily detected. UV-IF quantification was demonstrated using commercially available protein standards and provided more accurate and precise protein quantification than MS ion current. We evaluated the parallel use of UV-IF and top-down tandem MS for quantification and identification of protein subunits and associated proteins from an affinity-purified 26S proteasome sample from Arabidopsis thaliana. We identified 26 unique proteins and quantified 13 tryptophan-containing species. Our analyses discovered previously unidentified N-terminal processing of the β6 (PBF1) and β7 (PBG1) subunit - such processing of PBG1 may generate a heretofore unknown additional protease active site upon cleavage. In addition, our approach permitted the unambiguous identification and quantification both isoforms of the proteasome-associated protein DSS1. PMID:23536786

  6. Nigerian Physiotherapy Clinical Students' Perception of Their Learning Environment Measured by the Dundee Ready Education Environment Measure Inventory

    ERIC Educational Resources Information Center

    Odole, Adesola C.; Oyewole, Olufemi O.; Ogunmola, Oluwasolape T.

    2014-01-01

    The identification of the learning environment and the understanding of how students learn will help teacher to facilitate learning and plan a curriculum to achieve the learning outcomes. The purpose of this study was to investigate undergraduate physiotherapy clinical students' perception of University of Ibadan's learning environment. Using the…

  7. Radiation environment measurements on shuttle missions using the CREAM experiment

    NASA Astrophysics Data System (ADS)

    Dyer, C. S.; Sims, A. J.; Truscott, P. R.; Farren, J.; Underwood, C.

    1992-12-01

    The Cosmic Radiation Environment and Activation Monitor (CREAM) was successfully deployed in the middeck area on Shuttle missions STS-48 and STS-44 during September and November 1991 with the aim of monitoring those aspects of the primary and secondary radiation environment responsible for single event upsets in microelectronics and background noise in sensors. Results are compared with the outputs of standard radiation environment models. For the accurate location of trapped protons the choice of geomagnetic field model is shown to be critical, while results at high latitudes show the low-altitude manifestation of the new trapped proton belt observed to follow the March 1991 solar flare event. From deployment at a number of locations there is clear evidence for a significant build-up with shielding of secondary charged particles and neutrons.

  8. Shuttle measured contaminant environment and modeling for payloads. Preliminary assessment of the space telescope environment in the shuttle bay

    NASA Technical Reports Server (NTRS)

    Scialdone, J. J.

    1983-01-01

    A baseline gaseous and particulate environment of the Shuttle bay was developed based on the various measurements which were made during the first four flights of the Shuttle. The environment is described by the time dependent pressure, density, scattered molecular fluxes, the column densities and including the transient effects of water dumps, engine firings and opening and closing of the bay doors. The particulate conditions in the ambient and on surfaces were predicted as a function of the mission time based on the available data. This basic Shuttle environment when combined with the outgassing and the particulate contributions of the payloads, can provide a description of the environment of a payload in the Shuttle bay. As an example of this application, the environment of the Space Telescope in the bay, which may be representative of the environment of several payloads, was derived. Among the many findings obtained in the process of modeling the environment, one is that the payloads environment in the bay is not substantially different or more objectionable than the self-generated environment of a large payload or spacecraft. It is, however, more severe during ground facilities operations, the first 15 to 20 hours of the flight, during and for a short period after ater was dumped overboard, and the reaction control engines are being fired.

  9. An Evaluation of the Measurement of Perceived Classroom Assessment Environment

    ERIC Educational Resources Information Center

    Alkharusi, Hussain

    2015-01-01

    A classroom assessment environment is a classroom context experienced by students as the teacher determines assessment purposes, develops assessment tasks, defines assessment criteria and standards, provides feedback, and monitors outcomes (Brookhart, 1997). It is usually a group experience varying from class to class dependent upon the teacher's…

  10. Updated measurements from CREAM & CREDO & implications for environment & shielding models.

    PubMed

    Dyer, C S; Truscott, P R; Peerless, C L; Watson, C J; Evans, H E; Knight, P; Cosby, M; Underwood, C; Cousins, T; Noulty, R

    1998-06-01

    Flight data obtained between 1995 and 1997 from the Cosmic Radiation Environment Monitors CREAM & CREDO carried on UoSat-3, Space Shuttle, STRV-1a (Space Technology Research Vehicle) and APEX (Advanced Photovoltaic and Electronics Experiment Spacecraft) have been added to the dataset affording coverage since 1990. The modulation of cosmic rays and evolution of the South Atlantic Anomaly are observed, the former comprising a factor three increase at high latitudes and the latter a general increase accompanied by a westward drift. Comparison of particle fluxes and linear energy transfer spectra is made with improved environment & radiation transport calculations which account for shield distributions and secondary particles. While there is an encouraging convergence between predictions and observations, significant improvements are still required, particularly in the treatrnent of locally produced secondary particles. PMID:11542404

  11. Utilization of Low Gravity Environment for Measuring Liquid Viscosity

    NASA Technical Reports Server (NTRS)

    Antar, Basil N.; Ethridge, Edwin

    1998-01-01

    The method of drop coalescence is used for determining the viscosity of highly viscous undercooled liquids. Low gravity environment is necessary in order to allow for examining large volumes affording much higher accuracy for the viscosity calculations than possible for smaller volumes available under 1 - g conditions. The drop coalescence method is preferred over the drop oscillation technique since the latter method can only be applied for liquids with vanishingly small viscosities. The technique developed relies on both the highly accurate solution of the Navier-Stokes equations as well as on data from experiments conducted in near zero gravity environment. Results are presented for method validation experiments recently performed on board the NASA/KC-135 aircraft. While the numerical solution was produced using the Boundary Element Method. In these tests the viscosity of a highly viscous liquid, glycerine at room temperature, was determined using the liquid coalescence method. The results from these experiments will be discussed.

  12. A multi-sensor oceanographic measurement system for coastal environments

    USGS Publications Warehouse

    Martini, Marinna A.; Strahle, William J.

    1993-01-01

    An instrument system has been developed for long-term sediment transport studies that uses a modular design to combine off the shelf components into a complete and flexible package. A common data storage format is used in each instrument system so that the same hardware can be assembled in different ways to address specific scientific studies with minimal engineering support and modification. Three systems have been constructed and successfully deployed to date in two different coastal environments.

  13. Measuring transient high temperature thermal phenomena in hostile environment

    SciTech Connect

    Brenden, B.B.; Hartman, J.S.; Reich, F.R.

    1980-01-01

    The design of equipment for measuring temperature and strain in a rapidly heated and pressurized cylinder of stainless steel is discussed. Simultaneous cinematography of the full circumference of the cylinder without interference with temperature and strain measurements is also illustrated. The integrated system uses a reflective chamber for the sample and requires careful consideration of the spectral energy distribution utilized by each instrument.

  14. Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime Using Controlled Calorimetry

    SciTech Connect

    Don W. Miller; Andrew Kauffmann; Eric Kreidler; Dongxu Li; Hanying Liu; Daniel Mills; Thomas D. Radcliff; Joseph Talnagi

    2001-12-31

    A comprehensive description of the accomplishments of the DOE grant titled, ''Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime using Controlled Calorimetry''.

  15. Measuring fluid flow and heat output in seafloor hydrothermal environments

    NASA Astrophysics Data System (ADS)

    Germanovich, Leonid N.; Hurt, Robert S.; Smith, Joshua E.; Genc, Gence; Lowell, Robert P.

    2015-12-01

    We review techniques for measuring fluid flow and advective heat output from seafloor hydrothermal systems and describe new anemometer and turbine flowmeter devices we have designed, built, calibrated, and tested. These devices allow measuring fluid velocity at high- and low-temperature focused and diffuse discharge sites at oceanic spreading centers. The devices perform at ocean floor depths and black smoker temperatures and can be used to measure flow rates ranging over 2 orders of magnitude. Flow velocity is determined from the rotation rate of the rotor blades or paddle assembly. These devices have an open bearing design that eliminates clogging by particles or chemical precipitates as the fluid passes by the rotors. The devices are compact and lightweight enough for deployment from either an occupied or remotely operated submersible. The measured flow rates can be used in conjunction with vent temperature or geochemical measurements to obtain heat outputs or geochemical fluxes from both vent chimneys and diffuse flow regions. The devices have been tested on 30 Alvin dives on the Juan de Fuca Ridge and 3 Jason dives on the East Pacific Rise (EPR). We measured an anomalously low entrainment coefficient (0.064) and report 104 new measurements over a wide range of discharge temperatures (5°-363°C), velocities (2-199 cm/s), and depths (1517-2511 m). These include the first advective heat output measurements at the High Rise vent field and the first direct fluid flow measurement at Middle Valley. Our data suggest that black smoker heat output at the Main Endeavour vent field may have declined since 1994 and that after the 2005-2006 eruption, the high-temperature advective flow at the EPR 9°50'N field may have become more channelized, predominately discharging through the Bio 9 structure. We also report 16 measurements on 10 Alvin dives and 2 Jason dives with flow meters that predate devices described in this work and were used in the process of their development

  16. Vestibular ontogeny: Measuring the influence of the dynamic environment

    NASA Technical Reports Server (NTRS)

    Jones, Timothy A.; Devries, Sherri M.; Dubois, Linda M.; Nelson, Rick C.

    1993-01-01

    In comparison to other special senses, we are only meagerly informed about the development of vestibular function and the mechanisms that may operate to control or influence the course of vestibular ontogeny. Perhaps one contributing factor to this disparity is the difficulty of evaluating vestibular sense organs directly and noninvasively. The present report describes a recently developed direct noninvasive vestibular function test that can be used to address many basic questions about the developing vestibular system. More particularly, the test can be used to examine the effects of the dynamic environment (e.g. gravitational field and vibration) on vestibular ontogeny.

  17. Mobile measurement system of ECG signal in vehicle environment

    NASA Astrophysics Data System (ADS)

    Oh, Kwang-seok; Lee, Sang-Ryong; Lee, Choon-Young; Kim, Myun-Hee

    2005-12-01

    This paper proposed a new method to measure the ECG signal from the driver. The ECG signal is often measured in the room. But it is mixed with many kinds of noise when it is measured during the vehicle moving. Noise occupied most many parts as the experimental among them was classified. And one suitable filter for each noise was designed. It used ALE(Adaptive Line Enhancement) to remove the noise occurred to electromagnetic wave in vehicle. To remove the noise occurred to steering or vibration of vehicle, the paper used Wavelet transformation after ALE(preprocessing filter). To realize unconscious measurement, this research used the stainless steel(not the electrode) fixed at steering wheel and designed the adaptive filter without using reference signal.

  18. Measurement of Exercise Tolerance before Surgery (METS) study: a protocol for an international multicentre prospective cohort study of cardiopulmonary exercise testing prior to major non-cardiac surgery

    PubMed Central

    Pearse, Rupert M; Shulman, Mark A; Abbott, Tom E F; Torres, Elizabeth; Croal, Bernard L; Granton, John T; Thorpe, Kevin E; Grocott, Michael P W; Farrington, Catherine; Myles, Paul S; Cuthbertson, Brian H

    2016-01-01

    Introduction Preoperative functional capacity is considered an important risk factor for cardiovascular and other complications of major non-cardiac surgery. Nonetheless, the usual approach for estimating preoperative functional capacity, namely doctors’ subjective assessment, may not accurately predict postoperative morbidity or mortality. 3 possible alternatives are cardiopulmonary exercise testing; the Duke Activity Status Index, a standardised questionnaire for estimating functional capacity; and the serum concentration of N-terminal pro-B-type natriuretic peptide (NT pro-BNP), a biomarker for heart failure and cardiac ischaemia. Methods and analysis The Measurement of Exercise Tolerance before Surgery (METS) Study is a multicentre prospective cohort study of patients undergoing major elective non-cardiac surgery at 25 participating study sites in Australia, Canada, New Zealand and the UK. We aim to recruit 1723 participants. Prior to surgery, participants undergo symptom-limited cardiopulmonary exercise testing on a cycle ergometer, complete the Duke Activity Status Index questionnaire, undergo blood sampling to measure serum NT pro-BNP concentration and have their functional capacity subjectively assessed by their responsible doctors. Participants are followed for 1 year after surgery to assess vital status, postoperative complications and general health utilities. The primary outcome is all-cause death or non-fatal myocardial infarction within 30 days after surgery, and the secondary outcome is all-cause death within 1 year after surgery. Both receiver-operating-characteristic curve methods and risk reclassification table methods will be used to compare the prognostic accuracy of preoperative subjective assessment, peak oxygen consumption during cardiopulmonary exercise testing, Duke Activity Status Index scores and serum NT pro-BNP concentration. Ethics and dissemination The METS Study has received research ethics board approval at all sites

  19. Development and Datametric Properties of a Scale Measuring Students' Perceptions of the Classroom Assessment Environment

    ERIC Educational Resources Information Center

    Alkharusi, Hussain

    2011-01-01

    Each classroom has its own assessment environment perceived by the students and springs from the teacher's assessment practices. Although students' perceptions of the assessment environment may influence their achievement-related outcomes, little attention has been given to the measurement of perceived classroom assessment environment. This study…

  20. Checklist of Health Promotion Environments at Worksites (CHEW): Development and Measurement Characteristics.

    ERIC Educational Resources Information Center

    Oldenburg, Brian; Sallis, James F.; Harris, David; Owen, Neville

    2002-01-01

    Describes the development and administration of the Checklist of Health Promotion Environments at Worksites (CHEW), which measures health-promoting characteristics of the workplace environment by direct observation (physical characteristics, information environment, and immediate neighborhood). Findings illustrate the type of data on environmental…

  1. Measuring odours in the environment vs. dispersion modelling: A review

    NASA Astrophysics Data System (ADS)

    Capelli, Laura; Sironi, Selena; Del Rosso, Renato; Guillot, Jean-Michel

    2013-11-01

    Source characterization alone is not sufficient to account for the effective impact of odours on citizens, which would require to quantify odours directly at receptors. However, despite a certain simplicity of odour measurement at the emission source, odour measurement in the field is a quite more complicated task. This is one of the main reasons for the spreading of odour impact assessment approaches based on odour dispersion modelling. Currently, just a very limited number of reports discussing the use of tracer gas dispersion experiments both in the field and in wind tunnels for model validation purposes can be found in literature. However, when dealing with odour emissions, it is not always possible to identify a limited number of tracer compounds, nor to relate analytical concentrations to odour properties, thus giving that considering single odorous compounds might be insufficient to account for effective odour perception. For these reasons, the possibility of measuring of odours in the field, both as a way for directly assessing odour annoyance or for verifying that modelled odour concentrations correspond to the effective odour perception by humans, is still an important objective. The present work has the aim to review the techniques that can be adopted for measuring odours in the field, particularly discussing how such techniques can be used in alternative or in combination with odour dispersion models for odour impact assessment purposes, and how the results of field odour measurements and model outputs can be related and compared to each other.

  2. Feasibility analysis on integration of luminous environment measuring and design based on exposure curve calibration

    NASA Astrophysics Data System (ADS)

    Zou, Yuan; Shen, Tianxing

    2013-03-01

    Besides illumination calculating during architecture and luminous environment design, to provide more varieties of photometric data, the paper presents combining relation between luminous environment design and SM light environment measuring system, which contains a set of experiment devices including light information collecting and processing modules, and can offer us various types of photometric data. During the research process, we introduced a simulation method for calibration, which mainly includes rebuilding experiment scenes in 3ds Max Design, calibrating this computer aid design software in simulated environment under conditions of various typical light sources, and fitting the exposure curves of rendered images. As analytical research went on, the operation sequence and points for attention during the simulated calibration were concluded, connections between Mental Ray renderer and SM light environment measuring system were established as well. From the paper, valuable reference conception for coordination between luminous environment design and SM light environment measuring system was pointed out.

  3. MCG measurement in the environment of active magnetic shield.

    PubMed

    Yamazaki, K; Kato, K; Kobayashi, K; Igarashi, A; Sato, T; Haga, A; Kasai, N

    2004-01-01

    MCG (Magnetocardiography) measurement by a SQUID gradiometer was attempted with only active magnetic shielding (active shielding). A three-axis-canceling-coil active shielding system, where three 16-10-16 turns-coil sets were put in the orthogonal directions, produces a homogeneous magnetic field in a considerable volume surrounding the center. Fluxgate sensors were used as the reference sensors of the system. The system can reduce environmental magnetic noise at low frequencies of less than a few Hz, at 50 Hz and at 150 Hz. Reducing such disturbances stabilizes biomagnetic measurement conditions for SQUIDs in the absence of magnetically shielded rooms (MSR). After filtering and averaging the measured MCG data by a first-order SQUID gradiometer with only the active shielding during the daytime, the QRS complex and T wave was clearly presented. PMID:16012640

  4. Towards a mature measurement environment: Creating a software engineering research environment

    NASA Technical Reports Server (NTRS)

    Basili, Victor R.

    1990-01-01

    Software engineering researchers are building tools, defining methods, and models; however, there are problems with the nature and style of the research. The research is typically bottom-up, done in isolation so the pieces cannot be easily logically or physically integrated. A great deal of the research is essentially the packaging of a particular piece of technology with little indication of how the work would be integrated with other prices of research. The research is not aimed at solving the real problems of software engineering, i.e., the development and maintenance of quality systems in a productive manner. The research results are not evaluated or analyzed via experimentation or refined and tailored to the application environment. Thus, it cannot be easily transferred into practice. Because of these limitations we have not been able to understand the components of the discipline as a coherent whole and the relationships between various models of the process and product. What is needed is a top down experimental, evolutionary framework in which research can be focused, logically and physically integrated to produce quality software productively, and evaluated and tailored to the application environment. This implies the need for experimentation, which in turn implies the need for a laboratory that is associated with the artifact we are studying. This laboratory can only exist in an environment where software is being built, i.e., as part of a real software development and maintenance organization. Thus, we propose that Software Engineering Laboratory (SEL) type activities exist in all organizations to support software engineering research. We describe the SEL from a researcher's point of view, and discuss the corporate and government benefits of the SEL. The discussion focuses on the benefits to the research community.

  5. Force Exertion Capacity Measurements in Haptic Virtual Environments

    ERIC Educational Resources Information Center

    Munih, Marko; Bardorfer, Ales; Ceru, Bojan; Bajd, Tadej; Zupan, Anton

    2010-01-01

    An objective test for evaluating functional status of the upper limbs (ULs) in patients with muscular distrophy (MD) is presented. The method allows for quantitative assessment of the UL functional state with an emphasis on force exertion capacity. The experimental measurement setup and the methodology for the assessment of maximal exertable force…

  6. Ground-based Measurement Of Saharan Dust In Marine Environment

    NASA Astrophysics Data System (ADS)

    Jeong, M. J.; Ji, Q.; Tsay, S.; Hsu, C.; Hansell, R. A.; Augustine, D.

    2007-12-01

    An extensive field experiment, named NASA African Monsoon Multidisciplinary Analyses (NAMMA) was conducted during August-September of 2006 to investigate the genesis and development of hurricanes. Two ground-based mobile laboratories, Surface-sensing Measurements for Atmospheric Radiative Transfer (SMART) and Chemical, Optical, Microphysical Measurements of In-situ Troposphere (COMMIT), were deployed at Sal Island, Cape Verde to continuously monitor the structure and composition of the atmosphere in the major path of the Saharan Air Layer and the African Easterly Waves. A Micro-Pulse Lidar in SMART, which measures the vertical profiles of backscatter from the atmospheric particulates continuously, caught several episodes of Saharan dust layers reached the surface site. Simultaneously, physical and optical properties of aerosols (e.g., mixture of the Saharan dust and maritime aerosols) were captured by several instruments in COMMIT. In this study, we propose a novel method to separate dust properties from those of marine background aerosols by utilizing the synergy of a suite of in-situ measurements. Derived parameters are mass scattering coefficients and single scattering albedo (SSA) for dust near the surface (~10m). As a crosscheck, the SSA based on the surface measurements is compared with the result of Deep Blue satellite-based aerosol retrievals, which is now incorporated in the operational MODIS aerosol product. The presented preliminary results will be useful in studying the properties of Saharan dust originated from various source regions, which, in turns, can be used as inputs to aerosol transport models to help better understand the interactions between aerosol and cloud water cycle.

  7. Measuring the Restrictiveness of Living Environments for Children and Youth: Reconceptualizing Restriction

    ERIC Educational Resources Information Center

    Rauktis, Mary E.; Huefner, Jonathan C.; O'Brien, Kirk; Pecora, Peter J.; Doucette, Ann; Thompson, Ronald W.

    2009-01-01

    The "Restrictiveness of Living Environment Scale" has long been the primary way to conceptualize the "restrictiveness" of a child's living situation. However, changes in systems of care and other factors have created a need to revisit how restrictiveness is conceptualized and measured. A measure was created to assess an environment's level of…

  8. Scale Development of a Measure to Assess Community-Based and Clinical Intervention Group Environments

    ERIC Educational Resources Information Center

    Wilson, Patrick A.; Hansen, Nathan B.; Tarakeshwar, Nalini; Neufeld, Sharon; Kochman, Arlene; Sikkema, Kathleen J.

    2008-01-01

    Though group interventions are widely used in community-based and clinical settings, there are few brief instruments for assessing the group environment. Two studies on the development of a brief measure to assess intervention group environments are described, and psychometric properties of the new scale are presented. The new measure is based on…

  9. Measured Gene-by-Environment Interaction in Relation to Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Nigg, Joel; Nikolas, Molly; Burt, S. Alexandra

    2010-01-01

    Objective: To summarize and evaluate the state of knowledge regarding the role of measured gene-by-environment interactions in relation to attention-deficit/hyperactivity disorder. Method: A selective review of methodologic issues was followed by a systematic search for relevant articles on measured gene-by-environment interactions; the search…

  10. Measurement of surface reactions in the space environment

    NASA Technical Reports Server (NTRS)

    Abdou, Wedad A.; Megill, Lawrence R.; Brinza, David A.; Hart, Roger C.; Moore, R. Gilbert

    1989-01-01

    The Atomic Oxygen Measurement Spacecraft, ATOMS, and a suite of associated instruments, designed to measure the performance of improved atomic-oxygen-resistant materials and coatings in orbit and to telemeter the resulting data and video images to earth at intervals during a one-year mission, have been described in a definition study sponsored by the Langley Research Center under NASA's In-Space Technology Experiments Program. The objective of the program is to work toward an improvement of base materials and surface coatings which will resist the serious degradation experienced by the external surfaces of LEO spacecraft as a result of the ablative effects of atmospheric oxygen, possibly catalyzed by solar UV radiation. This miniature orbiting laboratory includes a radio-frequency mass spectrometer, a set of osmium actinometers, and a scanning optical microscope. The design of these instruments and their use in the overall experiment are discussed.

  11. Measuring the robustness of link prediction algorithms under noisy environment

    PubMed Central

    Zhang, Peng; Wang, Xiang; Wang, Futian; Zeng, An; Xiao, Jinghua

    2016-01-01

    Link prediction in complex networks is to estimate the likelihood of two nodes to interact with each other in the future. As this problem has applications in a large number of real systems, many link prediction methods have been proposed. However, the validation of these methods is so far mainly conducted in the assumed noise-free networks. Therefore, we still miss a clear understanding of how the prediction results would be affected if the observed network data is no longer accurate. In this paper, we comprehensively study the robustness of the existing link prediction algorithms in the real networks where some links are missing, fake or swapped with other links. We find that missing links are more destructive than fake and swapped links for prediction accuracy. An index is proposed to quantify the robustness of the link prediction methods. Among the twenty-two studied link prediction methods, we find that though some methods have low prediction accuracy, they tend to perform reliably in the “noisy” environment. PMID:26733156

  12. Measuring the robustness of link prediction algorithms under noisy environment

    NASA Astrophysics Data System (ADS)

    Zhang, Peng; Wang, Xiang; Wang, Futian; Zeng, An; Xiao, Jinghua

    2016-01-01

    Link prediction in complex networks is to estimate the likelihood of two nodes to interact with each other in the future. As this problem has applications in a large number of real systems, many link prediction methods have been proposed. However, the validation of these methods is so far mainly conducted in the assumed noise-free networks. Therefore, we still miss a clear understanding of how the prediction results would be affected if the observed network data is no longer accurate. In this paper, we comprehensively study the robustness of the existing link prediction algorithms in the real networks where some links are missing, fake or swapped with other links. We find that missing links are more destructive than fake and swapped links for prediction accuracy. An index is proposed to quantify the robustness of the link prediction methods. Among the twenty-two studied link prediction methods, we find that though some methods have low prediction accuracy, they tend to perform reliably in the “noisy” environment.

  13. Measuring the robustness of link prediction algorithms under noisy environment.

    PubMed

    Zhang, Peng; Wang, Xiang; Wang, Futian; Zeng, An; Xiao, Jinghua

    2016-01-01

    Link prediction in complex networks is to estimate the likelihood of two nodes to interact with each other in the future. As this problem has applications in a large number of real systems, many link prediction methods have been proposed. However, the validation of these methods is so far mainly conducted in the assumed noise-free networks. Therefore, we still miss a clear understanding of how the prediction results would be affected if the observed network data is no longer accurate. In this paper, we comprehensively study the robustness of the existing link prediction algorithms in the real networks where some links are missing, fake or swapped with other links. We find that missing links are more destructive than fake and swapped links for prediction accuracy. An index is proposed to quantify the robustness of the link prediction methods. Among the twenty-two studied link prediction methods, we find that though some methods have low prediction accuracy, they tend to perform reliably in the "noisy" environment. PMID:26733156

  14. Non-contact true temperature measurements in the microgravity environment

    NASA Technical Reports Server (NTRS)

    Khan, Mansoor A.; Allemand, Charly; Eagar, Thomas W.

    1989-01-01

    The theory developed is shown to be capable of calculating true temperature of any material from radiance measurements at a number of different wavelengths. This theory was also shown to be capable of predicting the uncertainty in these calculated temperatures. An additional advantage of these techniques is that they can estimate the emissivity of the target simultaneously with the temperature. This aspect can prove to be very important when a fast method of generating reflectivity vs. wavelength or emissivity vs. wavelength data is required. Experiments performed on various materials over a range of temperatures and experimental conditions were used to verify the accuracy of this theory.

  15. Measuring human capital cost through benchmarking in health care environment.

    PubMed

    Kocakülâh, Mehmet C; Harris, Donna

    2002-01-01

    Each organization should seek to maximize its human capital investments, which ultimately lead to increased profits and asset efficiency. Service companies utilize less capital equipment and more human productivity, customer service, and/or delivery of service as the product. With the measurement of human capital, one can understand what is happening, exercise some degree of control, and make positive changes. Senior management lives or dies by the numbers and if Human Resources (HR) really wants to be a strategic business partner, HR must be judged by the same standards as everyone else in the health care organization. PMID:12462657

  16. Mountain Heavy Rainfall Measurement Experiments in a Subtropical Monsoon Environment

    NASA Astrophysics Data System (ADS)

    Jong-Dao Jou, Ben; Chi-June Jung, Ultimate; Lai, Hsiao-Wei; Feng, Lei

    2014-05-01

    Quantitative rainfall measurement experiments have been conducted in Taiwan area for the past 5 years (since 2008), especially over the complex terrain region. In this paper, results from these experiments will be analyzed and discussed, especially those associated with heavy rain events in the summer monsoon season. Observations from s-band polarimetric radar (SPOL of NCAR) and also x-band vertically-pointing radar are analyzed to reveal the high resolution temporal and spatial variation of precipitation structure. May and June, the Meiyu season in the area, are months with subtropical frontal rainfall events. Mesoscale convective systems, i.e., pre-frontal squall lines and frontal convective rainbands, are very active and frequently produce heavy rain events over mountain areas. Accurate quantitative precipitation measurements are needed in order to meet the requirement for landslide and flood early warning purpose. Using ground-based disdrometers and vertically-pointing radar, we have been trying to modify the quantitative precipitation estimation in the mountain region by using coastal operational radar. In this paper, the methodology applied will be presented and the potential of its application will be discussed. *corresponding author: Ben Jong-Dao Jou, jouben43@gmail.com

  17. Cross-Level Measurement Invariance in School and Classroom Environment Surveys: Implications for Policy and Practice

    ERIC Educational Resources Information Center

    Schweig, Jonathan

    2014-01-01

    Measures of classroom and school environments are central to policy efforts that assess school and teacher quality. These measures are often formed by aggregating individual survey responses to form group-level measures, and assume an invariant measurement model holds across the individual and group levels. This article explores the tenability of…

  18. Measurement and modeling of phosphorous transport in shallow groundwater environments.

    PubMed

    Hendricks, G S; Shukla, S; Obreza, T A; Harris, W G

    2014-08-01

    added fertilizer P between HEI (187kg P2O5/ha) and REI (124kg P2O5/ha), soil Mehlich 1 P (M1P) values were similar for both systems while they received Pinput. Soil M1P for REI and REI-SD increased to a maximum of 55mg/kg while they received Pinput, and then gradually decreased after Pinput ceased. However, M1P for HEI increased steadily to a maximum of 145mg/kg by the end of the study with continued Pinput. Mehlich-1 P measured six years after the study still showed relatively high levels of P, a legacy effect of Pinput. The main factors influencing groundwater P concentration varied by seasons. During fall with frequent rainfall, the concentrations were influenced mainly by M1P and Pinput, and highlight a need for greater focus on Pinput management (vs. water management) during this season. However, during the dry period of spring, a greater focus on irrigation management is required since depth to water table and rainfall also become contributing factors. Three multivariate models (r(2)=0.67 to 0.93), for spring, fall, and annual periods, were developed for predicting groundwater P concentrations for a wide range of water and P inputs (0 to 191kg P2O5/ha of Pinput). The uniqueness of these models is that they use readily available hydrologic (rainfall and water table depth), management (Pinput), and soil (M1P) data commonly monitored by growers when managing water and nutrient inputs on agricultural landscapes. The development of similar models may not be necessary for other agro-ecosystems in similar regions since long-term data collected in these regions may be applied, with verification, to the models presented here. PMID:24981965

  19. Measurement and modeling of phosphorous transport in shallow groundwater environments

    NASA Astrophysics Data System (ADS)

    Hendricks, G. S.; Shukla, S.; Obreza, T. A.; Harris, W. G.

    2014-08-01

    amount of added fertilizer P between HEI (187 kg P2O5/ha) and REI (124 kg P2O5/ha), soil Mehlich 1 P (M1P) values were similar for both systems while they received Pinput. Soil M1P for REI and REI-SD increased to a maximum of 55 mg/kg while they received Pinput, and then gradually decreased after Pinput ceased. However, M1P for HEI increased steadily to a maximum of 145 mg/kg by the end of the study with continued Pinput. Mehlich-1 P measured six years after the study still showed relatively high levels of P, a legacy effect of Pinput. The main factors influencing groundwater P concentration varied by seasons. During fall with frequent rainfall, the concentrations were influenced mainly by M1P and Pinput, and highlight a need for greater focus on Pinput management (vs. water management) during this season. However, during the dry period of spring, a greater focus on irrigation management is required since depth to water table and rainfall also become contributing factors. Three multivariate models (r2 = 0.67 to 0.93), for spring, fall, and annual periods, were developed for predicting groundwater P concentrations for a wide range of water and P inputs (0 to 191 kg P2O5/ha of Pinput). The uniqueness of these models is that they use readily available hydrologic (rainfall and water table depth), management (Pinput), and soil (M1P) data commonly monitored by growers when managing water and nutrient inputs on agricultural landscapes. The development of similar models may not be necessary for other agro-ecosystems in similar regions since long-term data collected in these regions may be applied, with verification, to the models presented here.

  20. Airborne RF Measurement System (ARMS) and Analysis of Representative Flight RF Environment

    NASA Technical Reports Server (NTRS)

    Koppen, Sandra V.; Ely, Jay J.; Smith, Laura J.; Jones, Richard A.; Fleck, Vincent J.; Salud, Maria Theresa; Mielnik, John J.

    2007-01-01

    Environmental radio frequency (RF) data over a broad band of frequencies (30 MHz to 1000 MHz) were obtained to evaluate the electromagnetic environment in airspace around several airports. An RF signal measurement system was designed utilizing a spectrum analyzer connected to the NASA Lancair Columbia 300 aircraft's VHF/UHF navigation antenna. This paper presents an overview of the RF measurement system and provides analysis of sample RF signal measurement data. This aircraft installation package and measurement system can be quickly returned to service if needed by future projects requiring measurement of an RF signal environment or exploration of suspected interference situations.

  1. Constructing priors in synesthesia.

    PubMed

    van Leeuwen, Tessa M

    2014-01-01

    A new theoretical framework (PPSMC) applicable to synesthesia has been proposed, in which the discrepancy between the perceptual reality of (some) synesthetic concurrents and their subjective non-veridicality is being explained. The PPSMC framework stresses the relevance of the phenomenology of synesthesia for synesthesia research-and beyond. When describing the emergence and persistence of synesthetic concurrents under PPSMC, it is proposed that precise, high-confidence priors are crucial in synesthesia. I discuss the construction of priors in synesthesia. PMID:24702569

  2. A Student Environment Model: A Measure of Institutional Effectiveness. AIR 1998 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Morris-Baldwin, Darline

    This study traces the development of a student environment model (SEM) at Texas State Technical College (Waco) that is used to assess students' perceptions of their college environment outside the formal classroom, provides baseline data for comparative analyses, establishes goals for student support services, measures program and process…

  3. Measuring the Computer Classroom Environment: Lessons Learned from Using a New Instrument

    ERIC Educational Resources Information Center

    Logan, Keri A.; Crump, Barbara J.; Rennie, Leonie J.

    2006-01-01

    Research over the last four decades has shown that the classroom learning environment impacts on students' cognitive and affective outcomes. Different approaches have been taken to measure students' perceptions of their learning environment, and this has led to the development of a large number of survey instruments. One such instrument is the…

  4. Out with the Old, in with the New: Factor Analyses of a Classroom Environment Measure

    ERIC Educational Resources Information Center

    Boren, Rachel; Callahan, Carolyn; Peugh, James

    2011-01-01

    Several instruments have been developed to gauge student perceptions of their classroom environment as greater attention has been given to the relationship between student achievement and student perceptions. One widely used instrument to assess those perceptions is the Classroom Environment Scale (CES), a 90-item measure for secondary level…

  5. Developing the School Physical Activity and Nutrition Environment Tool to Measure Qualities of the Obesogenic Context

    ERIC Educational Resources Information Center

    John, Deborah H.; Gunter, Katherine; Jackson, Jennifer A.; Manore, Melinda

    2016-01-01

    Background: Practical tools are needed that reliably measure the complex physical activity (PA) and nutrition environments of elementary schools that influence children's health and learning behaviors for obesity prevention. The School Physical Activity and Nutrition-Environment Tool (SPAN-ET) was developed and beta tested in 6 rural Oregon…

  6. The CANEP Scale: Preliminary Psychometric Findings of a Measure of Youths' Perception of Their Neighborhood Environment

    ERIC Educational Resources Information Center

    Bisegger, Corinna; Cloetta, Bernhard; Ravens-Sieberer, Ulrike

    2008-01-01

    The impact of the environment on the quality of life and health is considered to be important for adults as well as for children and adolescents. To include the subjective view of children and adolescents in this context, instruments for measuring the perception of the environment are needed. The new scale CANEP (Children's and Adolescents'…

  7. Evaluation of a Brazilian Postgraduate Dental Program by the Dundee Ready Educational Environment Measure

    ERIC Educational Resources Information Center

    do Vale Placa, Rebeca; Ragghianti Zangrando, Mariana S.; Sant'Ana, Adriana C. P.; Greghi, Sebastião L. A.; de Rezende, Maria Lucia R.; Damante, Carla A.

    2015-01-01

    The evaluation of education environment is essential to provide to the professors a better understanding of the teaching process. One valuable tool for this assessment is the Dundee Ready Educational Environment Measure (DREEM). This questionnaire has 50 questions and is divided in five dimensions: D1--Perceptions of teaching, D2--Perceptions of…

  8. Business list vs. ground observation for measuring a food environment: saving time or waste of time (or worse)?

    PubMed Central

    Lucan, Sean C.; Maroko, Andrew R.; Bumol, Joel; Torrens, Luis; Varona, Monica; Berke, Ethan M.

    2013-01-01

    In food-environment research, an alternative to resource-intensive direct observation on the ground has been the use of commercial business lists. We sought to determine how well a frequently-used commercial business list measures a dense urban food environment like the Bronx. On 155 Bronx street segments, investigators compared two different levels for “matches” between the business list and direct ground observation: lenient (by business type) and strict (by business name). For each level of matching, researchers calculated sensitivities and positive predictive values (PPVs) for the business list overall and by broad business categories: General grocers (e.g., supermarkets), Specialty-food stores (e.g., produce markets), Restaurants, and Businesses not primarily selling food (e.g., newsstands). Even after cleaning the business list (e.g., for cases of multiple listings at a single location), and allowing for inexactness in listed street addresses and spellings of business names, the overall performance of the business list was poor. For strict “matches”, the business list had an overall sensitivity of 39.3% and PPV of 45.5%. Sensitivities and PPVs by broad business categories were not meaningfully different from overall values, although sensitivity for General grocers and PPV for Specialty-food stores were particularly low: 26.2% and 32.0% respectively. For lenient “matches”, sensitivities and PPVs were somewhat higher but still poor: 52.4–60.0% and 60.0–75.0% respectively. The business list is inadequate to measures the actual food environment in the Bronx. If results represent performance in other settings, findings from prior studies linking food environments to diet and diet-related health outcomes using such business lists are in question, and future studies of this type should avoid relying solely on such business lists. PMID:23871107

  9. Protecting tripartite entanglement in non-Markovian environments via quantum partially collapsing measurements

    NASA Astrophysics Data System (ADS)

    Ding, Zhi-Yong; He, Juan; Ye, Liu

    2016-08-01

    In this paper, the dynamics of tripartite entanglement via π -tangle in independent non-Markovian environments is investigated. The results indicate that the π -tangle vanishes periodically as decoherence time increases with a damping of its revival amplitude due to the memory of the non-Markovian environments. In addition, we present a scheme to protect entanglement of W state from non-Markovian environments by means of the quantum partially collapsing measurements. It is worth mentioning that our scheme is a successful protection for the tripartite quantum system and the effect is better for the larger measurement strength, while the stronger decoherence suppression induces smaller success probability.

  10. Geometric measure of quantum correlation: The influence of the asymmetry environments

    NASA Astrophysics Data System (ADS)

    Zhu, Qinsheng; Ding, Changchun; Wu, Shaoyi; Lai, Wei

    2016-09-01

    The quantum correlation in open quantum systems is of fundamental and practical importance for quantum information processing and controllable nanometer devices. And the properties of quantum correlation can be influenced by the information flow between systems and environments. In this study, we investigated the geometric measure discord of quantum correlation of a two qubits system, interacting with two independent and intrinsic interacting spin-environments, respectively. Based on the asymmetry environments with comparable parameters, the different properties of the geometric measure of entanglement and quantum discord are displayed and discussed for initial Bell states.

  11. Measuring the Environment for Friendliness Toward Physical Activity: A Comparison of the Reliability of 3 Questionnaires

    PubMed Central

    Brownson, Ross C.; Chang, Jen Jen; Eyler, Amy A.; Ainsworth, Barbara E.; Kirtland, Karen A.; Saelens, Brian E.; Sallis, James F.

    2004-01-01

    Objectives. We tested the reliability of 3 instruments that assessed social and physical environments. Methods. We conducted a test–retest study among US adults (n = 289). We used telephone survey methods to measure suitableness of the perceived (vs objective) environment for recreational physical activity and nonmotorized transportation. Results. Most questions in our surveys that attempted to measure specific characteristics of the built environment showed moderate to high reliability. Questions about the social environment showed lower reliability than those that assessed the physical environment. Certain blocks of questions appeared to be selectively more reliable for urban or rural respondents. Conclusions. Despite differences in content and in response formats, all 3 surveys showed evidence of reliability, and most items are now ready for use in research and in public health surveillance. PMID:14998817

  12. Measuring Physical Activity in Outdoor Community Recreational Environments: Implications for Research, Policy, and Practice

    PubMed Central

    Jones, Sydney A.; Stransky, Michelle; Evenson, Kelly R.

    2015-01-01

    Chronic diseases such as cardiovascular disease (CVD) are major contributors to escalating health care costs in the USA. Physical activity is an important protective factor against CVD, and the National Prevention Strategy recognizes active living (defined as a way of life that integrates physical activity into everyday routines) as a priority for improving the nation’s health. This paper focuses on developing more inclusive measures of physical activity in outdoor community recreational environments, specifically parks and trails, to enhance their usability for at-risk populations such as persons with mobility limitations. We develop an integrated conceptual framework for measuring physical activity in outdoor community recreational environments, describe examples of evidence-based tools for measuring physical activity in these settings, and discuss strategies to improve measurement of physical activity for persons with mobility limitations. Addressing these measurement issues is critically important to making progress towards national CVD goals pertaining to active community environments. PMID:26005510

  13. Development and Validation of Short Forms of Some Instruments Measuring Student Perceptions of Actual and Preferred Classroom Learning Environment.

    ERIC Educational Resources Information Center

    Fraser, Barry J.; Fisher, Darrell L.

    1983-01-01

    Describes development/validation of short forms of Individualized Classroom Environment Questionnaire (ICEQ), My Class Inventory (MCI), and Classroom Environment Scale (CES). In addition to these forms measuring perceptions of actual classroom environment, ICEQ and CES short forms measuring preferred classroom environment were also developed.…

  14. An examination of speech reception thresholds measured in a simulated reverberant cafeteria environment

    PubMed Central

    Best, Virginia; Keidser, Gitte; Buchholz, J(x004E7)rg M.; Freeston, Katrina

    2016-01-01

    Objective There is increasing demand in the hearing research community for the creation of laboratory environments that better simulate challenging real-world listening environments. The hope is that the use of such environments for testing will lead to more meaningful assessments of listening ability, and better predictions about the performance of hearing devices. Here we present one approach for simulating a complex acoustic environment in the laboratory, and investigate the effect of transplanting a speech test into such an environment. Design Speech reception thresholds were measured in a simulated reverberant cafeteria, and in a more typical anechoic laboratory environment containing background speech babble. Study Sample The participants were 46 listeners varying in age and hearing levels, including 25 hearing-aid wearers who were tested with and without their hearing aids. Results Reliable SRTs were obtained in the complex environment, but led to different estimates of performance and hearing aid benefit from those measured in the standard environment. Conclusions The findings provide a starting point for future efforts to increase the real-world relevance of laboratory-based speech tests. PMID:25853616

  15. Dyslexics' usage of visual priors is impaired.

    PubMed

    Jaffe-Dax, Sagi; Lieder, Itay; Biron, Tali; Ahissar, Merav

    2016-07-01

    Human perception benefits substantially from familiarity, via the formation of effective predictions of the environment's pattern of stimulation. Basic stimulation characteristics are automatically retrieved and integrated into our perception. A quantitatively measurable manifestation of the integration of priors is known as "contraction to the mean"; i.e., perception is biased toward the experienced mean. We previously showed that in the context of auditory discrimination, the magnitude of this bias is smaller among dyslexic individuals than among good readers matched for age and general reasoning skills. Here we examined whether a similarly reduced contraction characterizes dyslexics' behavior on serial visual tasks. Using serial spatial frequency discrimination tasks, we found that dyslexics' bias toward the experiment's mean spatial frequency was smaller than that observed for the controls. Thus, dyslexics' difficulties in automatic detection and integration of stimulus statistics are domain-general. These difficulties are likely to impede the acquisition of reading expertise. PMID:27472497

  16. Environment.

    ERIC Educational Resources Information Center

    White, Gilbert F.

    1980-01-01

    Presented are perspectives on the emergence of environmental problems. Six major trends in scientific thinking are identified including: holistic approaches to examining environments, life support systems, resource management, risk assessment, streamlined methods for monitoring environmental change, and emphasis on the global framework. (Author/SA)

  17. Measurement with verification of stationary signals and noise in extremely quiet environments: Measuring below the noise floor

    PubMed Central

    Ellingson, Roger M.; Gallun, Frederick J.; Bock, Guillaume

    2015-01-01

    It can be problematic to measure stationary acoustic sound pressure level in any environment when the target level approaches or lies below the minimum measureable sound pressure level of the measurement system itself. This minimum measureable level, referred to as the inherent measurement system noise floor, is generally established by noise emission characteristics of measurement system components such as microphones, preamplifiers, and other system circuitry. In this paper, methods are presented and shown accurate measuring stationary levels within 20 dB above and below this system noise floor. Methodology includes (1) measuring inherent measurement system noise, (2) subtractive energy based, inherent noise adjustment of levels affected by system noise floor, and (3) verifying accuracy of inherent noise adjustment technique. While generalizable to other purposes, the techniques presented here were specifically developed to quantify ambient noise levels in very quiet rooms used to evaluate free-field human hearing thresholds. Results obtained applying the methods to objectively measure and verify the ambient noise level in an extremely quiet room, using various measurement system noise floors and analysis bandwidths, are presented and discussed. The verified results demonstrate the adjustment method can accurately extend measurement range to 20 dB below the measurement system noise floor, and how measurement system frequency bandwidth can affect accuracy of reported noise levels. PMID:25786932

  18. Measurement with verification of stationary signals and noise in extremely quiet environments: measuring below the noise floor.

    PubMed

    Ellingson, Roger M; Gallun, Frederick J; Bock, Guillaume

    2015-03-01

    It can be problematic to measure stationary acoustic sound pressure level in any environment when the target level approaches or lies below the minimum measureable sound pressure level of the measurement system itself. This minimum measureable level, referred to as the inherent measurement system noise floor, is generally established by noise emission characteristics of measurement system components such as microphones, preamplifiers, and other system circuitry. In this paper, methods are presented and shown accurate measuring stationary levels within 20 dB above and below this system noise floor. Methodology includes (1) measuring inherent measurement system noise, (2) subtractive energy based, inherent noise adjustment of levels affected by system noise floor, and (3) verifying accuracy of inherent noise adjustment technique. While generalizable to other purposes, the techniques presented here were specifically developed to quantify ambient noise levels in very quiet rooms used to evaluate free-field human hearing thresholds. Results obtained applying the methods to objectively measure and verify the ambient noise level in an extremely quiet room, using various measurement system noise floors and analysis bandwidths, are presented and discussed. The verified results demonstrate the adjustment method can accurately extend measurement range to 20 dB below the measurement system noise floor, and how measurement system frequency bandwidth can affect accuracy of reported noise levels. PMID:25786932

  19. The concordance of directly and indirectly measured built environment attributes and physical activity adoption

    PubMed Central

    2011-01-01

    Background Physical activity (PA) adoption is essential for obesity prevention and control, yet ethnic minority women report lower levels of PA and are at higher risk for obesity and its comorbidities compared to Caucasians. Epidemiological studies and ecologic models of health behavior suggest that built environmental factors are associated with health behaviors like PA, but few studies have examined the association between built environment attribute concordance and PA, and no known studies have examined attribute concordance and PA adoption. Purpose The purpose of this study was to associate the degree of concordance between directly and indirectly measured built environment attributes with changes in PA over time among African American and Hispanic Latina women participating in a PA intervention. Method Women (N = 410) completed measures of PA at Time 1 (T1) and Time 2 (T2); environmental data collected at T1 were used to compute concordance between directly and indirectly measured built environment attributes. The association between changes in PA and the degree of concordance between each directly and indirectly measured environmental attribute was assessed using repeated measures analyses. Results There were no significant associations between built environment attribute concordance values and change in self-reported or objectively measured PA. Self-reported PA significantly increased over time (F(1,184) = 7.82, p = .006), but this increase did not vary by ethnicity or any built environment attribute concordance variable. Conclusions Built environment attribute concordance may not be associated with PA changes over time among minority women. In an effort to promote PA, investigators should clarify specific built environment attributes that are important for PA adoption and whether accurate perceptions of these attributes are necessary, particularly among the vulnerable population of minority women. PMID:21736740

  20. Measurement and Characterization of the Acceleration Environment on Board the Space Station

    NASA Technical Reports Server (NTRS)

    Baugher, Charles R. (Editor)

    1990-01-01

    This workshop provides a comprehensive overview of the work and status of each of these areas to provide a basis for establishing a systematic approach to the challenge of avoiding these difficulties during the Space Station era of materials experimentation. The discussions were arranged in the order of: the scientific understanding of the requirements for a micro-gravity environment, a history of acceleration measurements on spacecraft, the state of accelerometer technology, and the current understanding of the predicted Space Station environment.

  1. Comparative measurements of single event upset and total dose environments using the CREAM instruments

    SciTech Connect

    Dyer, C.S.; Sims, A.J. ); Farren, J.; Stephen, J. ); Underwood, C. )

    1992-06-01

    This paper reports that the Cosmic Radiation Environment and Activation Monitor (CREAM) is taking regular measurements in the upper atmosphere on board the supersonic Concorde, while a further version of the same instrument is currently scheduled for flight on the Space Shuttle during September and November 1991. Meanwhile a sister instrument (CREDO) is continuously monitoring the environment in sun-synchronous orbit on board UOSAT-3. These contemporaneous flights of similar instruments enable intercomparison of environments as well as verification of predictive models and correlation with device behavior. The extensive data set encompasses both quiet-time data and solar-particle events.

  2. Recovering full coherence in a qubit by measuring half of its environment

    NASA Astrophysics Data System (ADS)

    Miatto, Filippo M.; Piché, Kevin; Brougham, Thomas; Boyd, Robert W.

    2015-12-01

    When a quantum system interacts with its environment it may incur in decoherence. Quantum erasure makes it possible to restore coherence in a system by gaining information about its environment, but measuring the whole of it may be prohibitive: Realistically, one might be forced to address only an accessible subspace and neglect the rest. In such a case, under what conditions will quantum erasure still be effective? In this work we compute analytically the largest recoverable coherence of a random qubit plus environment state and we show that it approaches 100% with overwhelmingly high probability as long as the dimension of the accessible subspace of the environment is larger than √{D }, where D is the dimension of the whole environment. Additionally, we find a sharp transition between a linear behavior and a power-law behavior as soon as the dimension of the inaccessible environment exceeds the dimension of the accessible one. Our results imply that the typical states of a qubit plus environment system admit a measurement spanning only about √{D } degrees of freedom, any outcome of which projects the qubit on a maximally coherent state. This suggests, for instance, that in the dynamics of open quantum systems, if the interactions are known, it would in principle be possible to gain sufficient information and restore coherence in a qubit by dealing with a fraction of the physical resources.

  3. Enhancing Robustness of Entanglement in Finite Temperature Environment Using Quantum Measurement Reversal

    NASA Astrophysics Data System (ADS)

    Hu, Yao-Hua; Tong, Lei; Tan, Yong-Gang; Fang, Mao-Fa

    2016-03-01

    We demonstrate methods of enhancing robustness of entanglement of two-qubit systems undergoing generalized amplitude damping decoherence using weak measurement and measurement reversal. The results show that the local action of generalized amplitude damping noise can cause sudden death of entanglement, and the weak measurement and measurement reversal is useful for combating generalized amplitude damping decoherence and recovering the entanglement of two entangled qubits. In addition, the results indicate that it would be much more easily implemented by applying quantum measurement reversal on a single-qubit to enhance robustness of entanglement in finite temperature environment, than on both qubits.

  4. Prior Computer Experience and Technology Acceptance

    ERIC Educational Resources Information Center

    Varma, Sonali

    2010-01-01

    Prior computer experience with information technology has been identified as a key variable (Lee, Kozar, & Larsen, 2003) that can influence an individual's future use of newer computer technology. The lack of a theory driven approach to measuring prior experience has however led to conceptually different factors being used interchangeably in…

  5. Mars' Surface Radiation Environment Measured with the Mars Science Laboratory's Curiosity Rover

    NASA Astrophysics Data System (ADS)

    Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L.; Brinza, David E.; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A.; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A.; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P.; MSL Science Team; Kemppinen, Osku; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; Berger, Thomas; Matthia, Daniel; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Hamilton, Victoria; Peterson, Joseph; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; García, César Martín; Mueller-Mellin, Reinhold; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

    2014-01-01

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

  6. Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

    PubMed

    Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

    2014-01-24

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment. PMID:24324275

  7. An Inexpensive, Stable, and Accurate Relative Humidity Measurement Method for Challenging Environments

    PubMed Central

    Zhang, Wei; Ma, Hong; Yang, Simon X.

    2016-01-01

    In this research, an improved psychrometer is developed to solve practical issues arising in the relative humidity measurement of challenging drying environments for meat manufacturing in agricultural and agri-food industries. The design in this research focused on the structure of the improved psychrometer, signal conversion, and calculation methods. The experimental results showed the effect of varying psychrometer structure on relative humidity measurement accuracy. An industrial application to dry-cured meat products demonstrated the effective performance of the improved psychrometer being used as a relative humidity measurement sensor in meat-drying rooms. In a drying environment for meat manufacturing, the achieved measurement accuracy for relative humidity using the improved psychrometer was ±0.6%. The system test results showed that the improved psychrometer can provide reliable and long-term stable relative humidity measurements with high accuracy in the drying system of meat products. PMID:26999161

  8. Performance measurement and modeling of component applications in a high performance computing environment : a case study.

    SciTech Connect

    Armstrong, Robert C.; Ray, Jaideep; Malony, A.; Shende, Sameer; Trebon, Nicholas D.

    2003-11-01

    We present a case study of performance measurement and modeling of a CCA (Common Component Architecture) component-based application in a high performance computing environment. We explore issues peculiar to component-based HPC applications and propose a performance measurement infrastructure for HPC based loosely on recent work done for Grid environments. A prototypical implementation of the infrastructure is used to collect data for a three components in a scientific application and construct performance models for two of them. Both computational and message-passing performance are addressed.

  9. The measured radiation environment within Spacelabs 1 and 2 and comparison with predictions

    NASA Technical Reports Server (NTRS)

    Parnell, T. A.; Watts, J. W., Jr.; Fishman, G. J.; Benton, E. V.; Frank, A. L.

    1986-01-01

    A set of passive and active radiation detectors was flown as part of the verification flight instrumentation (VFI) in an attempt to measure the radiation environment in the Spacelab (SL) module and on the pallet. SL 1 carried 4 passive and 2 active detector packages which were used to evaluate the radiation environment within the spacecraft and SL 2 carried 2 passive VFI units on the pallet. Dose equivalents of 330 + or - 70 mrem and 537 + or - 37 mrem were measured in the SL 1 module and SL 2 pallet, respectively.

  10. Measurement of surface profile in vibrating environment with instantaneous phase shifting interferometry

    NASA Astrophysics Data System (ADS)

    Sivakumar, N. R.; Tan, B.; Venkatakrishnan, K.

    2006-01-01

    In-process measurement has been the requirement of the precision industries, but due to vibrations while manufacturing, in-process measurement has been difficult to achieve. There is little work on in-process measurement using phase shifting interferometry, as phase shifting is extremely sensitive to vibrations. In this work, the advantage of the developed non-mechanical and instantaneous phase shifting interferometry is felt while measuring surface profile of large flat surfaces under vibrating conditions which can be extended for in-process measurement of surface profile. A near common path optical configuration is achieved and the effect of the environment is reduced. Moreover, the measurement of phase is instantaneous which increases the versatility of this technique for measuring vibrating objects. Profile measurements were carried out on a smooth mirror surface excited with vibrations of different frequencies and the technique was found to be immune to vibrations of up to 1000 Hz.

  11. Analogue Materials Measured Under Simulated Lunar and Asteroid Environments: Application to Thermal Infrared Measurements of Airless Bodies

    NASA Astrophysics Data System (ADS)

    Donaldson Hanna, K. L.; Pieters, C. M.; Patterson, W., III; Moriarty, D.

    2012-12-01

    Remote sensing observations provide key insights into the composition and evolution of planetary surfaces. A fundamentally important component to any remote sensing study of planetary surfaces is laboratory measurements of well-characterized samples measured under the appropriate environmental conditions. The near-surface vacuum environment of airless bodies like the Moon and asteroids creates a thermal gradient in the upper hundred microns of regolith. Lab studies of particulate rocks and minerals as well as selected lunar soils under vacuum and lunar-like conditions have identified significant effects of this thermal gradient on thermal infrared (TIR) spectral measurements [e.g. Logan et al. 1973, Salisbury and Walter 1989, Thomas et al. 2010, Donaldson Hanna et al. 2012]. Compared to ambient conditions, these effects include: (1) the Christiansen feature (CF), an emissivity maximum diagnostic of mineralogy and average composition, shifts to higher wavenumbers and (2) an increase in spectral contrast of the CF relative to the Reststrahlen bands (RB), the fundamental molecular vibration bands due to Si-O stretching and bending. Such lab studies demonstrate the high sensitivity of TIR emissivity spectra to environmental conditions under which they are measured. The Asteroid and Lunar Environment Chamber (ALEC) is the newest addition to the RELAB at Brown University. The vacuum chamber simulates the space environment experienced by the near-surface soils of the Moon and asteroids. The internal rotation stage allows for six samples and two blackbodies to be measured without breaking vacuum (<10-4 mbar). Liquid nitrogen is used to cool the interior of the chamber, creating a cold, low emission environment (mimicking the space environment) for heated samples to radiate into. Sample cups can be heated in one of three configurations: (1) from below using heaters embedded in the base of the sample cup, (2) from above using a solar-like radiant heat source, and (3) from

  12. Precise Temperature Measurement for Increasing the Survival of Newborn Babies in Incubator Environments

    PubMed Central

    Frischer, Robert; Penhaker, Marek; Krejcar, Ondrej; Kacerovsky, Marian; Selamat, Ali

    2014-01-01

    Precise temperature measurement is essential in a wide range of applications in the medical environment, however the regarding the problem of temperature measurement inside a simple incubator, neither a simple nor a low cost solution have been proposed yet. Given that standard temperature sensors don't satisfy the necessary expectations, the problem is not measuring temperature, but rather achieving the desired sensitivity. In response, this paper introduces a novel hardware design as well as the implementation that increases measurement sensitivity in defined temperature intervals at low cost. PMID:25494352

  13. Rayleigh Scattering Diagnostic for Measurement of Temperature and Velocity in Harsh Environments

    NASA Technical Reports Server (NTRS)

    Seasholtz, Richard G.; Greer, Lawrence C., III

    1998-01-01

    A molecular Rayleigh scattering system for temperature and velocity measurements in unseeded flows is described. The system is capable of making measurements in the harsh environments commonly found in aerospace test facilities, which may have high acoustic sound levels, varying temperatures, and high vibration levels. Light from an argon-ion laser is transmitted via an optical fiber to a remote location where two flow experiments were located. One was a subsonic free air jet; the second was a low-speed heated airjet. Rayleigh scattered light from the probe volume was transmitted through another optical fiber from the remote location to a controlled environment where a Fabry-Perot interferometer and cooled CCD camera were used to analyze the Rayleigh scattered light. Good agreement between the measured velocity and the velocity calculated from isentropic flow relations was demonstrated (less than 5 m/sec). The temperature measurements, however, exhibited systematic errors on the order of 10-15%.

  14. Headaches prior to earthquakes

    NASA Astrophysics Data System (ADS)

    Morton, L. L.

    1988-06-01

    In two surveys of headaches it was noted that their incidence had increased significantly within 48 h prior to earthquakes from an incidence of 17% to 58% in the first survey using correlated samples and from 20.4% to 44% in the second survey using independent samples. It is suggested that an increase in positive air ions from rock compression may trigger head pain via a decrease in brain levels of the neurotransmitter serotonin. The findings are presented as preliminary, with the hope of generating further research efforts in areas more prone to earthquakes.

  15. Measuring College Students' Alcohol Consumption in Natural Drinking Environments: Field Methodologies for Bars and Parties

    ERIC Educational Resources Information Center

    Clapp, John D.; Holmes, Megan R.; Reed, Mark B.; Shillington, Audrey M.; Freisthler, Bridget; Lange, James E.

    2007-01-01

    In recent years researchers have paid substantial attention to the issue of college students' alcohol use. One limitation to the current literature is an over reliance on retrospective, self-report survey data. This article presents field methodologies for measuring college students' alcohol consumption in natural drinking environments.…

  16. Radiation counting technique allows density measurement of metals in high-pressure/ high-temperature environment

    NASA Technical Reports Server (NTRS)

    Dillion, I. G.; Nelson, P. A.; Swanson, B. S.

    1967-01-01

    Radioactive tracers induced by neutron irradiation provide a gamma ray flux proportional to the density of a metal, allowing density measurement of these metals in extreme high-temperature and high-pressure environments. This concept is applicable to most metals, as well as other substances.

  17. Deceived by Omission: The Difficulty of Matching Measurement and Theory When Assessing the Home Environment.

    ERIC Educational Resources Information Center

    Bradley, Robert H.

    2000-01-01

    Focuses on theoretical and practical difficulties in constructing and evaluating a measure of the home environment of a diversity of families. Describes limitations of theory to guide developmental indicator selection and ways to deal with these limitations. Discusses rationale for selecting criteria for judging test validity and use of cause…

  18. Analysis and Interpretation of Twin Studies Including Measures of the Shared Environment

    ERIC Educational Resources Information Center

    Turkheimer, Eric; D'Onofrio, Brian M.; Maes, Hermine H.; Eaves, Lindon J.

    2005-01-01

    Recent reports using a classical behavior genetic research design in which twin data are combined with a measured characteristic of their shared family environment have made striking claims about estimating environmental influences on behavior with genetic effects controlled. Such claims are overstated for two related reasons. First, when a…

  19. Elastic and plastic strain measurement in high temperature environment using laser speckle

    NASA Technical Reports Server (NTRS)

    Chiang, Fu-Pen

    1992-01-01

    Two laser speckle methods are described to measure strain in high temperature environment and thermal strain caused by high temperature. Both are non-contact, non-destructive and remote sensing techniques that can be automated. The methods have different but overlapping ranges of application with one being more suitable for large plastic deformation.

  20. Measuring School Climate in High Schools: A Focus on Safety, Engagement, and the Environment

    ERIC Educational Resources Information Center

    Bradshaw, Catherine P.; Waasdorp, Tracy E.; Debnam, Katrina J.; Johnson, Sarah Lindstrom

    2014-01-01

    Background: School climate has been linked to multiple student behavioral, academic, health, and social-emotional outcomes. The US Department of Education (USDOE) developed a 3-factor model of school climate comprised of safety, engagement, and environment. This article examines the factor structure and measurement invariance of the USDOE model.…

  1. An assessment of corrections for eddy covariance measured turbulent fluxes over snow in mountain environments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Snow-covered complex terrain is an extremely important runoff generating landscape in high altitude and latitude environments, yet is often considered non-viable for eddy covariance measurements of turbulent fluxes. Turbulent flux data are useful for evaluating the coupled snow cover mass and energ...

  2. Perceived and Objective Measures of Neighborhood Environment for Physical Activity Among Mexican Adults, 2011

    PubMed Central

    Salvo, Deborah; Lamadrid-Figueroa, Héctor; Hernández, Bernardo; Rivera-Dommarco, Juan A.; Pratt, Michael

    2016-01-01

    Introduction Environmental supports for physical activity may help residents to be physically active. However, such supports might not help if residents’ perceptions of the built environment do not correspond with objective measures. We assessed the associations between objective and perceived measures of the built environment among adults in Cuernavaca, Mexico, and examined whether certain variables modified this relationship. Methods We conducted a population-based (n = 645) study in 2011 that used objective (based on geographic information systems) and perceived (by questionnaire) measures of the following features of the built environment: residential density, mixed-land use, intersection density, and proximity to parks and transit stops. We used linear regression to assess the adjusted associations between these measures and to identify variables modifying these relationships. Results Adjusted associations were significant for all features (P < .05) except intersection density and proximity to transit stops. Significantly stronger associations between perceived and objective measures were observed among participants with low socioeconomic status, participants who did not own a motor vehicle or did not meet physical activity recommendations, and participants perceiving parks as safe. Conclusion Perceived measures of residential density, mixed-land use, and proximity to parks are associated with objective environmental measures related to physical activity. However, in Mexico, it should not be assumed that perceived measures of intersection density and proximity to transit stops are the same as objective measures. Our results are consistent with those from high-income countries in that associations between perceived and objective measures are modified by individual sociodemographic and psychosocial factors. PMID:27281391

  3. Direct measurements of near-highway emissions in a high diesel environment

    NASA Astrophysics Data System (ADS)

    DeWitt, H. L.; Hellebust, S.; Temime-Roussel, B.; Ravier, S.; Polo, L.; Jacob, V.; Buisson, C.; Charron, A.; André, M.; Pasquier, A.; Besombes, J. L.; Jaffrezo, J. L.; Wortham, H.; Marchand, N.

    2014-10-01

    Diesel-powered passenger cars currently outnumber gasoline-powered cars in many countries, particularly in Europe. In France, diesel cars represented 61% of Light Duty Vehicles in 2011 and this percentage is still increasing (French Environment and Energy Management Agency, ADEME). As part of the September~2011 joint PM-DRIVE (Particulate Matter- DiRect and Indirect on-road Vehicular Emissions) and MOCOPO (Measuring and mOdeling traffic COngestion and POllution) field campaign, the concentration and high-resolution chemical composition of aerosols and volatile organic carbon (VOC) species were measured adjacent to a major urban highway south of Grenoble, France. Alongside these atmospheric measurements, detailed traffic data were collected from nearby traffic cameras and loop detectors, which allowed the identification of vehicle type and characteristics, traffic concentration, and traffic speed to be quantified and compared to measured aerosol and VOCs. Six aerosol age and source profiles were resolved using the positive matrix factorization (PMF) model on real-time high-resolution aerosol mass spectra. These six aerosol source/age categories included a hydrocarbon-like organic aerosol (HOA) commonly associated with primary vehicular emissions, a nitrogen containing aerosol (NOA) with a diurnal pattern similar to that of HOA, oxidized organic aerosol (OOA), and biomass burning aerosol (BBOA). While quantitatively separating the influence of diesel vs. gasoline proved impossible, a low HOA : black carbon ratio, similar to that measured in other high-diesel environments, and high levels of NOx, also indicative of diesel emissions, were observed. A comparison between these high-diesel environment measurements and measurements taken in low-diesel (North American) environments was examined and the potential feedback between vehicular emissions and SOA formation was probed. Although the measurement site was located next to a large source of primary emissions, which are

  4. Physical Processes and Real-Time Chemical Measurement of the Insect Olfactory Environment

    PubMed Central

    Abrell, Leif; Hildebrand, John G.

    2009-01-01

    Odor-mediated insect navigation in airborne chemical plumes is vital to many ecological interactions, including mate finding, flower nectaring, and host locating (where disease transmission or herbivory may begin). After emission, volatile chemicals become rapidly mixed and diluted through physical processes that create a dynamic olfactory environment. This review examines those physical processes and some of the analytical technologies available to characterize those behavior-inducing chemical signals at temporal scales equivalent to the olfactory processing in insects. In particular, we focus on two areas of research that together may further our understanding of olfactory signal dynamics and its processing and perception by insects. First, measurement of physical atmospheric processes in the field can provide insight into the spatiotemporal dynamics of the odor signal available to insects. Field measurements in turn permit aspects of the physical environment to be simulated in the laboratory, thereby allowing careful investigation into the links between odor signal dynamics and insect behavior. Second, emerging analytical technologies with high recording frequencies and field-friendly inlet systems may offer new opportunities to characterize natural odors at spatiotemporal scales relevant to insect perception and behavior. Characterization of the chemical signal environment allows the determination of when and where olfactory-mediated behaviors may control ecological interactions. Finally, we argue that coupling of these two research areas will foster increased understanding of the physicochemical environment and enable researchers to determine how olfactory environments shape insect behaviors and sensory systems. PMID:18548311

  5. Measurement in a marine environment using low cost sensors of temperature and dissolved oxygen

    USGS Publications Warehouse

    Godshall, F.A.; Cory, R.L.; Phinney, D.E.

    1974-01-01

    Continuous records of physical parameters of the marine environment are difficult as well as expensive to obtain. This paper describes preliminary results of an investigative program with the purpose of developing low cost time integrating measurement and averaging devices for water temperature and dissolved oxygen. Measurements were made in an estuarine area of the Chesapeake Bay over two week periods. With chemical thermometers average water temperature for the two week period was found to be equal to average water temperature measured with thermocouples plus or minus 1.0 C. The slow diffusion of oxygen through the semipermiable sides of plastic bottles permitted the use of water filled bottles to obtain averaged oxygen measurements. Oxygen measurements for two week averaging times using 500 ml polyethylene bottles were found to vary from conventionally measured and averaged dissolved oxygen by about 1.8 mg/l. ?? 1974 Estuarine Research Federation.

  6. Mobile robot self-localization system using single webcam distance measurement technology in indoor environments.

    PubMed

    Li, I-Hsum; Chen, Ming-Chang; Wang, Wei-Yen; Su, Shun-Feng; Lai, To-Wen

    2014-01-01

    A single-webcam distance measurement technique for indoor robot localization is proposed in this paper. The proposed localization technique uses webcams that are available in an existing surveillance environment. The developed image-based distance measurement system (IBDMS) and parallel lines distance measurement system (PLDMS) have two merits. Firstly, only one webcam is required for estimating the distance. Secondly, the set-up of IBDMS and PLDMS is easy, which only one known-dimension rectangle pattern is needed, i.e., a ground tile. Some common and simple image processing techniques, i.e., background subtraction are used to capture the robot in real time. Thus, for the purposes of indoor robot localization, the proposed method does not need to use expensive high-resolution webcams and complicated pattern recognition methods but just few simple estimating formulas. From the experimental results, the proposed robot localization method is reliable and effective in an indoor environment. PMID:24473282

  7. Mobile Robot Self-Localization System Using Single Webcam Distance Measurement Technology in Indoor Environments

    PubMed Central

    Li, I-Hsum; Chen, Ming-Chang; Wang, Wei-Yen; Su, Shun-Feng; Lai, To-Wen

    2014-01-01

    A single-webcam distance measurement technique for indoor robot localization is proposed in this paper. The proposed localization technique uses webcams that are available in an existing surveillance environment. The developed image-based distance measurement system (IBDMS) and parallel lines distance measurement system (PLDMS) have two merits. Firstly, only one webcam is required for estimating the distance. Secondly, the set-up of IBDMS and PLDMS is easy, which only one known-dimension rectangle pattern is needed, i.e., a ground tile. Some common and simple image processing techniques, i.e., background subtraction are used to capture the robot in real time. Thus, for the purposes of indoor robot localization, the proposed method does not need to use expensive high-resolution webcams and complicated pattern recognition methods but just few simple estimating formulas. From the experimental results, the proposed robot localization method is reliable and effective in an indoor environment. PMID:24473282

  8. A Model of Generating Visual Place Cells Based on Environment Perception and Similar Measure.

    PubMed

    Zhou, Yang; Wu, Dewei

    2016-01-01

    It is an important content to generate visual place cells (VPCs) in the field of bioinspired navigation. By analyzing the firing characteristic of biological place cells and the existing methods for generating VPCs, a model of generating visual place cells based on environment perception and similar measure is abstracted in this paper. VPCs' generation process is divided into three phases, including environment perception, similar measure, and recruiting of a new place cell. According to this process, a specific method for generating VPCs is presented. External reference landmarks are obtained based on local invariant characteristics of image and a similar measure function is designed based on Euclidean distance and Gaussian function. Simulation validates the proposed method is available. The firing characteristic of the generated VPCs is similar to that of biological place cells, and VPCs' firing fields can be adjusted flexibly by changing the adjustment factor of firing field (AFFF) and firing rate's threshold (FRT). PMID:27597859

  9. A Model of Generating Visual Place Cells Based on Environment Perception and Similar Measure

    PubMed Central

    2016-01-01

    It is an important content to generate visual place cells (VPCs) in the field of bioinspired navigation. By analyzing the firing characteristic of biological place cells and the existing methods for generating VPCs, a model of generating visual place cells based on environment perception and similar measure is abstracted in this paper. VPCs' generation process is divided into three phases, including environment perception, similar measure, and recruiting of a new place cell. According to this process, a specific method for generating VPCs is presented. External reference landmarks are obtained based on local invariant characteristics of image and a similar measure function is designed based on Euclidean distance and Gaussian function. Simulation validates the proposed method is available. The firing characteristic of the generated VPCs is similar to that of biological place cells, and VPCs' firing fields can be adjusted flexibly by changing the adjustment factor of firing field (AFFF) and firing rate's threshold (FRT). PMID:27597859

  10. The application of magnetic measurements for the characterization of atmospheric particulate pollution within the airport environment.

    PubMed

    Jones, S; Richardson, N; Bennett, M; Hoon, S R

    2015-01-01

    The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of atmospheric particulate matter (PM) on health and the environment. PM within the airport environment may be derived from a range of sources. To date, however, the identification of individual sources of airport derived PM has remained elusive but constitutes a research priority for the aviation industry.The aim of this research was to identify distinctive and characteristic fingerprints of atmospheric PM derived from various sources in an airport environment through the use of environmental magnetic measurements. PM samples from aircraft engine emissions, brake wear and tire wear residues have been obtained from a range of different aircraft and engine types. Samples have been analyzed utilizing a range of magnetic mineral properties indicative of magnetic mineralogy and grain size. Results indicate that the dusts from the three 'aircraft' sources, (i.e. engines, brakes and tires) display distinctive magnetic mineral characteristics which may serve as 'magnetic fingerprints' for these sources. Magnetic measurements of runway dusts collected at different locations on the runway surface also show contrasting magnetic characteristics which, when compared with those of the aircraft-derived samples, suggest that they may relate to different sources characteristic of aircraft emissions at various stages of the take-off/landing cycle. The findings suggest that magnetic measurements could have wider applicability for the differentiation and identification of PM within the airport environment. PMID:25265399

  11. Near-highway aerosol and gas-phase measurements in a high-diesel environment

    NASA Astrophysics Data System (ADS)

    DeWitt, H. L.; Hellebust, S.; Temime-Roussel, B.; Ravier, S.; Polo, L.; Jacob, V.; Buisson, C.; Charron, A.; André, M.; Pasquier, A.; Besombes, J. L.; Jaffrezo, J. L.; Wortham, H.; Marchand, N.

    2015-04-01

    Diesel-powered passenger cars currently outnumber gasoline-powered cars in many countries, particularly in Europe. In France, diesel cars represented 61% of light duty vehicles in 2011 and this percentage is still increasing (French Environment and Energy Management Agency, ADEME). As part of the September 2011 joint PM-DRIVE (Particulate Matter - DiRect and Indirect on-road Vehicular Emissions) and MOCOPO (Measuring and mOdeling traffic COngestion and POllution) field campaign, the concentration and high-resolution chemical composition of aerosols and volatile organic carbon species were measured adjacent to a major urban highway south of Grenoble, France. Alongside these atmospheric measurements, detailed traffic data were collected from nearby traffic cameras and loop detectors, which allowed the vehicle type, traffic concentration, and traffic speed to be quantified. Six aerosol age and source profiles were resolved using the positive matrix factorization model on real-time high-resolution aerosol mass spectra. These six aerosol source/age categories included a hydrocarbon-like organic aerosol (HOA) commonly associated with primary vehicular emissions, a nitrogen-containing aerosol with a diurnal pattern similar to that of HOA, oxidized organic aerosol (OOA), and biomass burning aerosol. While quantitatively separating the influence of diesel from that of gasoline proved impossible, a low HOA : black carbon ratio, similar to that measured in other high-diesel environments, and high levels of NOx, also indicative of diesel emissions, were observed. Although the measurement site was located next to a large source of primary emissions, which are typically found to have low oxygen incorporation, OOA was found to comprise the majority of the measured organic aerosol, and isotopic analysis showed that the measured OOA contained mainly modern carbon, not fossil-derived carbon. Thus, even in this heavily vehicular-emission-impacted environment, photochemical processes

  12. Underwater measurement of narrowband sound power and directivity using Supersonic Intensity in Reverberant Environments

    NASA Astrophysics Data System (ADS)

    Barnard, Andrew R.; Hambric, Stephen A.; Maynard, Julian D.

    2012-08-01

    A laboratory underwater acoustic measurement technique, Supersonic Intensity in Reverberant Environments (SIRE), is developed analytically and validated experimentally and numerically. Unlike standard free or diffuse field techniques, SIRE enables the measurement of narrowband sound power and directivity in an environment with inexact field conditions. The technique takes advantage of underwater vector sensors, measuring only acoustic pressure and the normal component of particle velocity/acceleration, and supersonic wavenumber filtering in the near field of a source. The result is outward-propagating acoustic waves separated from interfering incoming and/or evanescent waves. The SIRE technique was experimentally applied to monopole and dipole sources and the results are compared with theory and standard methods. SIRE is shown to accurately measure radiated sound power to within the limits of ANSI S12.51 and to accurately measure the directivity indices of simple sources to within ±3 dB. A coupled finite element/boundary element model of a point-driven, thin-walled cylinder is also developed to establish the limitations of the SIRE technique. The model results show that the measurement standoff distance should be less than the reciprocal of the largest wavenumber in the frequency band of interest. Furthermore, the maximum measurement grid spacing must be less than twice the standoff distance.

  13. District-level local measuring program of the urban environment in Budapest

    NASA Astrophysics Data System (ADS)

    Dian, Csenge; Pongrácz, Rita; Dezsö, Zsuzsanna; Bartholy, Judit

    2016-04-01

    The natural environment and thus, the climatic conditions are modified by the concentrated human presence of urban areas. In our research we aim to analyze the resulting urban climatic effects in a downtown district of Budapest, Hungary. For this purpose, we have started a measuring program of in-situ measurements in the southern central located district called Ferencváros, which can be found near the river Danube, and mainly consists of 3- and 4-storey older and newly built buildings. The newly built buildings are mainly the results of the Ferencváros local government's efforts to improve the environment for the citizens. Within the framework of the block rehabilitation program, inner parts of the old house blocks were demolished, and inside the blocks common green areas have been created. In our urban climate measurement program air temperature and relative humidity are recorded along a pre-defined path consisting of 22 measuring points, which covers the studied area. The measuring sites are located in different characteristical points of the district, such as green parks, narrow streets, paved squares and roads. In order to calculate the urban heat island intensity, temperature measurements are compared to the hourly recorded data of the Budapest synoptic station (ID number: 12843) located in the southeastern suburb district of the city. After completing an entire year of measurements, the seasonal cycle of temperature and relative humidity differences are analyzed as well, as the diurnal changes and the spatial structure within the study area.

  14. Characterizing ISS Charging Environments with On-Board Ionospheric Plasma Measurements

    NASA Technical Reports Server (NTRS)

    Minow, Jospeh I.; Craven, Paul D.; Coffey, Victoria N.; Schneider, Todd A.; Vaughn, Jason A.; Wright Jr, Kenneth; Parker, Paul D.; Mikatarian, Ronald R.; Kramer, Leonard; Hartman, William A.; Alred, John W.; Koontz, Steven L.

    2008-01-01

    Charging of the International Space Station (ISS) is dominated by interactions of the biased United States (US) 160 volt solar arrays with the relatively high density, low temperature plasma environment in low Earth orbit. Conducting surfaces on the vehicle structure charge negative relative to the ambient plasma environment because ISS structure is grounded to the negative end of the US solar arrays. Transient charging peaks reaching potentials of some tens of volts negative controlled by photovoltaic array current collection typically occur at orbital sunrise and sunset as well as near orbital noon. In addition, surface potentials across the vehicle structure vary due to an induced v x B (dot) L voltage generated by the high speed motion of the conducting structure across the Earth's magnetic field. Induced voltages in low Earth orbit are typically only approx.0.4 volts/meter but the approx.100 meter scale dimensions of the ISS yield maximum induced potential variations ofapprox.40 volts across the vehicle. Induced voltages are variable due to the orientation of the vehicle structure and orbital velocity vector with respect to the orientation of the Earth's magnetic field along the ISS orbit. In order to address the need to better understand the ISS spacecraft potential and plasma environments, NASA funded development and construction of the Floating Potential Measurement Unit (FPMU) which was deployed on an ISS starboard truss arm in August 2006. The suite of FPMU instruments includes two Langmuir probes, a plasma impedance probe, and a potential probe for use in in-situ monitoring of electron temperatures and densities and the vehicle potential relative to the plasma environment. This presentation will describe the use of the FPMU to better characterize interactions of the ISS with the space environment, changes in ISS charging as the vehicle configuration is modified during ISS construction, and contributions of FPMU vehicle potential and plasma environment

  15. Thermal history sensors for non-destructive temperature measurements in harsh environments

    SciTech Connect

    Pilgrim, C. C.; Heyes, A. L.; Feist, J. P.

    2014-02-18

    The operating temperature is a critical physical parameter in many engineering applications, however, can be very challenging to measure in certain environments, particularly when access is limited or on rotating components. A new quantitative non-destructive temperature measurement technique has been proposed which relies on thermally induced permanent changes in ceramic phosphors. This technique has several distinct advantages over current methods for many different applications. The robust ceramic material stores the temperature information allowing long term thermal exposures in harsh environment to be measured at a convenient time. Additionally, rare earth dopants make the ceramic phosphorescent so that the temperature information can be interpreted by automated interrogation of the phosphorescent light. This technique has been demonstrated by application of YAG doped with dysprosium and europium as coatings through the air-plasma spray process. Either material can be used to measure temperature over a wide range, namely between 300°C and 900°C. Furthermore, results show that the material records the peak exposure temperature and prolonged exposure at lower temperatures would have no effect on the temperature measurement. This indicates that these materials could be used to measure peak operating temperatures in long-term testing.

  16. Assessing validity and reliability of Dundee ready educational environment measure (DREEM) in Iran

    PubMed Central

    Koohpayehzadeh, Jalil; Hashemi, Akram; Soltani Arabshahi, Kamran; Bigdeli, Shoaleh; Moosavi, Maryam; Hatami, Kamran; Baradaran, Hamid Reza

    2014-01-01

    Background: If an institute is looking for improvement of its learning environment, a reliable and valid assessment tool is needed for measurement of the educational environment .The Dundee Ready Educational Environment Measure (DREEM) has been used in various studies to evaluate the educational environment. However, psychometric evaluations of the instrument seem necessary, for all known versions of the instrument. The aim of this study was to investigate the reliability and validity of Persian version of the DREEM in the major clinical wards in teaching hospitals affiliated to Iran University of Medical Sciences. Methods: This descriptive - analytical study, involved medical students (clinical stagers and interns) in 4 major clinical wards. In this study, DREEM questionnaire was reviewed in content, face validity and construct validity through confirmatory factor analysis. The reliability was calculated according to test - retest and the internal consistency was measured using Cronbach's alpha coefficient. Results: A total number of 267 questionnaires were completed by medical stagers (60%) and interns (40%) including 181 females and 82 males. The mean age of stagers and interns were 23.60 ± 1.27 and 25.45 ± 1.22 years, respectively. The total mean of the questionnaire was calculated as 96.15 (93.5375, 98.7547) out of 176, with 95% confidence interval. The face validity of the questionnaire was confirmed. The mean of content validity ratio (CVR) was calculated as 0.35, and 6 questions were omitted in this step. The content validity index (CVI) was 0.39. The reliability coefficient mean was 0.71. In confirmatory factor analysis five factors were confirmed that changed the orientation of some questions. The Cronbach's alpha coefficient of the whole questionnaire was obtained as 0.914. Conclusion: The modified and validates DREEM questionnaire in Persian language with 44 items and appropriate psychometric attributes is capable of being used in assessment of

  17. The acoustic environment of intensive care wards based on long period nocturnal measurements.

    PubMed

    Xie, Hui; Kang, Jian

    2012-01-01

    The patients in the Intensive Care Units are often exposed to excessive levels of noise and activities. They can suffer from sleep disturbance, especially at night, but they are often too ill to cope with the poor environment. This article investigates the acoustic environment of typical intensive care wards in the UK, based on long period nocturnal measurements, and examines the differences between singlebed and multibed wards, using statistical analysis. It has been shown that the acoustic environment differs significantly every night. There are also significant differences between the noise levels in the singlebed and multibed wards, where acoustic ceilings are present. Despite the similar background noises in both ward types, more intrusive noises tend to originate from the multibed wards, while more extreme sounds are likely to occur in the single wards. The sound levels in the measured wards for each night are in excess of the World Health Organization's (WHO) guide levels by at least 20 dBA, dominantly at the middle frequencies. Although the sound level at night varies less than that in the daytime, the nocturnal acoustic environment is not dependant on any specific time, thus neither the noisiest nor quietest period can be determined. It is expected that the statistical analysis of the collected data will provide essential information for the development of relevant guidelines and noise reduction strategies. PMID:23117538

  18. Validation of PhenX measures in the personalized medicine research project for use in gene/environment studies

    PubMed Central

    2014-01-01

    Background The purpose of this paper is to describe the data collection efforts and validation of PhenX measures in the Personalized Medicine Research Project (PMRP) cohort. Methods Thirty-six measures were chosen from the PhenX Toolkit within the following domains: demographics; anthropometrics; alcohol, tobacco and other substances; cardiovascular; environmental exposures; cancer; psychiatric; neurology; and physical activity and physical fitness. Eligibility criteria for the current study included: living PMRP subjects with known addresses who consented to future contact and were not currently living in a nursing home, available GWAS data from eMERGE I for subjects where age-related cataract, HDL, dementia and resistant hypertension were the primary phenotypes, thus biasing the sample to the older PMRP participants. The questionnaires were mailed twice. Data from the PhenX measures were compared with information from PMRP questionnaires and data from Marshfield Clinic electronic medical records. Results Completed PhenX questionnaires were returned by 2271 subjects for a final response rate of 70%. The mean age reported on the PhenX questionnaire (73.1 years) was greater than the PMRP questionnaire (64.8 years) because the data were collected at different time points. The mean self-reported weight, and subsequently calculated BMI, were less on the PhenX survey than the measured values at the time of enrollment into PMRP (PhenX means 173.5 pounds and BMI 28.2 kg/m2 versus PMRP 182.9 pounds and BMI 29.6 kg/m2). There was 95.3% agreement between the two questionnaires about having ever smoked at least 100 cigarettes. 139 (6.2%) of subjects indicated on the PhenX questionnaire that they had been told they had a stroke. Of them, only 15 (10.8%) had no electronic indication of a prior stroke or TIA. All of the age-and gender-specific 95% confidence limits around point estimates for major depressive episodes overlap and show that 31% of women aged 50–64 reported

  19. Unconsciously elicited perceptual prior

    PubMed Central

    Chang, Raymond; Baria, Alexis T.; Flounders, Matthew W.; He, Biyu J.

    2016-01-01

    Increasing evidence over the past decade suggests that vision is not simply a passive, feed-forward process in which cortical areas relay progressively more abstract information to those higher up in the visual hierarchy, but rather an inferential process with top-down processes actively guiding and shaping perception. However, one major question that persists is whether such processes can be influenced by unconsciously perceived stimuli. Recent psychophysics and neuroimaging studies have revealed that while consciously perceived stimuli elicit stronger responses in higher visual and frontoparietal areas than those that fail to reach conscious awareness, the latter can still drive high-level brain and behavioral responses. We investigated whether unconscious processing of a masked natural image could facilitate subsequent conscious recognition of its degraded counterpart (a black-and-white “Mooney” image) presented many seconds later. We found that this is indeed the case, suggesting that conscious vision may be influenced by priors established by unconscious processing of a fleeting image.

  20. Exhaust environment measurements of a turbofan engine equipped with an afterburner and 2D nozzle

    NASA Technical Reports Server (NTRS)

    Brase, L. O.

    1990-01-01

    A test to measure the acoustic noise and static pressure environment on a structure exposed to engine exhaust flow was conducted at the NASA Lewis Research Center Propulsion Systems Laboratory by using an F100 derivative engine with a two-dimensional convergent-divergent (2D/CD) non-flight-weight demonstrator nozzle. A highly instrumented, water cooled flat panel was placed behind the 2D/CD nozzle, and tests were conducted at simulated Mach/altitude flight conditions with the engine at military or maximum-afterburner power setting. The panel instrumentation consisted of acoustic pressure microphones, thermocouples, and static-pressure pickups. Measurements indicated that the exhaust environment may excite structural resonances up to 10,000 HZ and that overall sound pressure levels decrease with increasing altitude.

  1. Current and Near-Term Future Measurements of the Orbital Debris Environment at NASA

    NASA Technical Reports Server (NTRS)

    Stansbery, Gene; Liou, J.-C.; Mulrooney, M.; Horstman, M

    2010-01-01

    The NASA Orbital Debris Program Office places great emphasis on obtaining and understanding direct measurements of the orbital debris environment. The Orbital Debris Program Office's environmental models are all based on these measurements. Because OD measurements must cover a very wide range of sizes and altitudes, one technique realistically cannot be used for all measurements. In general, radar measurements have been used for lower altitudes and optical measurements for higher altitude orbits. For very small debris, in situ measurements such as returned spacecraft surfaces are utilized. In addition to receiving information from large debris (> 5-10 cm diameter) from the U.S. Space Surveillance Network, NASA conducts statistical measurements of the debris population for smaller sizes. NASA collects data from the Haystack and Goldstone radars for debris in low Earth orbit as small as 2- 4 mm diameter and from the Michigan Orbital DEbris Survey Telescope for debris near geosynchronous orbit altitude for sizes as small as 30-60 cm diameter. NASA is also currently examining the radiator panel of the Hubble Space Telescope Wide Field Planetary Camera 2 which was exposed to space for 16 years and was recently returned to Earth during the STS- 125 Space Shuttle mission. This paper will give an overview of these on-going measurement programs at NASA as well as discuss progress and plans for new instruments and techniques in the near future.

  2. Characteristic measurements of silicon dioxide aerogel plasmas generated in a Planckian radiation environment

    SciTech Connect

    Dong Quanli; Wang Shoujun; Li Yutong; Zhang Yi; Zhao Jing; Wei Huigang; Shi Jianrong; Zhao Gang; Zhang Jiyan; Gu Yuqiu; Ding Yongkun; Wen Tianshu; Zhang Wenhai; Hu Xin; Liu Shenye; Zhang Lin; Tang Yongjian; Zhang Baohan; Zheng Zhijian; Nishimura, Hiroaki

    2010-01-15

    The temporally and spatially resolved characteristics of silicon dioxide aerogel plasmas were studied using x-ray spectroscopy. The plasma was generated in the near-Planckian radiation environment within gold hohlraum targets irradiated by laser pulses with a total energy of 2.4 kJ in 1 ns. The contributions of silicon ions at different charge states to the specific components of the measured absorption spectra were also investigated. It was found that each main feature in the absorption spectra of the measured silicon dioxide aerogel plasmas was contributed by two neighboring silicon ionic species.

  3. Measurement of the equilibrium factor between radon and its progeny in the underground mining environment.

    PubMed

    Ntwaeaborwa, O M; Kgwadi, N D; Taole, S H; Strydom, R

    2004-04-01

    A scintillation cell and a portable radiation spectrometer for radon progeny were respectively employed to measure the concentration of radon and that of its progeny in the underground gold mine environment. The measured concentrations were subsequently used to calculate the equilibrium factor between radon and its progeny. The results obtained indicate that various locations underground have different values of radon concentration and ratios of radon concentration to its progeny concentration. The differences can be ascribed to variations in grades of uranium at different locations and to some environmental factors such as ventilation, particle concentration, and the deposition of the progeny on surfaces or on the atmospheric aerosol. PMID:15057058

  4. Defining Neighbourhoods as a Measure of Exposure to the Food Environment.

    PubMed

    Lyseen, Anders K; Hansen, Henning S; Harder, Henrik; Jensen, Anders S; Mikkelsen, Bent E

    2015-07-01

    Neighbourhoods are frequently used as a measure for individuals' exposure to the food environment. However, the definitions of neighbourhoods fluctuate and have not been applied consistently in previous studies. Neighbourhoods defined from a single fixed location fail to capture people's complete exposure in multiple locations, but measuring behaviour using traditional methods can be challenging. This study compares the traditional methods of measuring exposure to the food environment to methods that use data from GPS tracking. For each of the 187 participants, 11 different neighbourhoods were created in which the exposure to supermarkets and fast food outlets were measured. ANOVA, Tukey's Honestly Significant Difference (HSD) test and t-tests were performed to compare the neighbourhoods. Significant differences were found between area sizes and the exposure to supermarkets and fast food outlets for different neighbourhood types. Second, significant differences in exposure to food outlets were found between the urban and rural neighbourhoods. Neighbourhoods are clearly a diffused and blurred concept that varies in meaning depending on each person's perception and the conducted study. Complexity and heterogeneity of human mobility no longer appear to correspond to the use of residential neighbourhoods but rather emphasise the need for methods, concepts and measures of individual activity and exposure. PMID:26197331

  5. Defining Neighbourhoods as a Measure of Exposure to the Food Environment

    PubMed Central

    Lyseen, Anders K.; Hansen, Henning S.; Harder, Henrik; Jensen, Anders S.; Mikkelsen, Bent E.

    2015-01-01

    Neighbourhoods are frequently used as a measure for individuals’ exposure to the food environment. However, the definitions of neighbourhoods fluctuate and have not been applied consistently in previous studies. Neighbourhoods defined from a single fixed location fail to capture people’s complete exposure in multiple locations, but measuring behaviour using traditional methods can be challenging. This study compares the traditional methods of measuring exposure to the food environment to methods that use data from GPS tracking. For each of the 187 participants, 11 different neighbourhoods were created in which the exposure to supermarkets and fast food outlets were measured. ANOVA, Tukey’s Honestly Significant Difference (HSD) test and t-tests were performed to compare the neighbourhoods. Significant differences were found between area sizes and the exposure to supermarkets and fast food outlets for different neighbourhood types. Second, significant differences in exposure to food outlets were found between the urban and rural neighbourhoods. Neighbourhoods are clearly a diffused and blurred concept that varies in meaning depending on each person’s perception and the conducted study. Complexity and heterogeneity of human mobility no longer appear to correspond to the use of residential neighbourhoods but rather emphasise the need for methods, concepts and measures of individual activity and exposure. PMID:26197331

  6. A New Correction Technique for Strain-Gage Measurements Acquired in Transient-Temperature Environments

    NASA Technical Reports Server (NTRS)

    Richards, W. Lance

    1996-01-01

    Significant strain-gage errors may exist in measurements acquired in transient-temperature environments if conventional correction methods are applied. As heating or cooling rates increase, temperature gradients between the strain-gage sensor and substrate surface increase proportionally. These temperature gradients introduce strain-measurement errors that are currently neglected in both conventional strain-correction theory and practice. Therefore, the conventional correction theory has been modified to account for these errors. A new experimental method has been developed to correct strain-gage measurements acquired in environments experiencing significant temperature transients. The new correction technique has been demonstrated through a series of tests in which strain measurements were acquired for temperature-rise rates ranging from 1 to greater than 100 degrees F/sec. Strain-gage data from these tests have been corrected with both the new and conventional methods and then compared with an analysis. Results show that, for temperature-rise rates greater than 10 degrees F/sec, the strain measurements corrected with the conventional technique produced strain errors that deviated from analysis by as much as 45 percent, whereas results corrected with the new technique were in good agreement with analytical results.

  7. Adding Papillomacular Bundle Measurements to Standard Optical Coherence Tomography Does Not Increase Sensitivity to Detect Prior Optic Neuritis in Patients with Multiple Sclerosis

    PubMed Central

    Laible, Mona; Jarius, Sven; Schmidt-Bacher, Annette; Platten, Michael; Haas, Jürgen

    2016-01-01

    Purpose To improve the detection of retinal nerve fiber layer (RNFL) thinning in multiple sclerosis (MS), a special peripapillary ring scanning algorithm (N-site RNFL, N-RNFL) was developed for spectral domain optical coherence tomography (SD-OCT). In contrast to the standard protocol (ST-RNFL) scanning starts nasally, not temporally, and provides an additional sector of analysis, the papillomacular bundle (PMB). We aimed to ascertain whether the temporal RNFL differs between the two techniques, whether N-RNFL is more sensitive than ST-RNFL to detect previous optic neuritis (ON), and whether analyzing the PMB adds additional sensitivity. Furthermore, we investigated whether RNFL is associated with disease severity and/or disease duration. Methods We conducted a cross-sectional case-control study of 38 patients with MS, of whom 24 had a history of ON, and 40 healthy controls (HC). Subjects with ON within the previous 6 months were excluded. Records included clinical characteristics, visual evoked potentials (VEP), and SD-OCT in both techniques. Results In a total of 73 evaluable MS eyes, temporal N-RNFL was abnormal in 17.8%, temporal ST-RNFL in 19.2%, and the PMB-RNFL in 21.9%. In ON eyes, the sensitivity of temporal N-RNFL and ST-RNFL did not differ significantly (37.0%/33.3%, p = 0.556). The sensitivity of VEP was 85.2%. RNFL thickness was associated with disease severity in all eyes, with and without a history of ON, and with disease duration. Conclusion The two OCT techniques detected previous ON with similar sensitivity, but the sensitivity of VEPs was superior to that of both N-RNFL and ST-RNFL. Our results indicate that the widely used ST-RNFL technique is appropriate for peripapillary RNFL measurements in MS patients. PMID:27171375

  8. Development of an instrument to measure medical students’ perceptions of the assessment environment: initial validation

    PubMed Central

    Hiong Sim, Joong; Ting Tong, Wen; Hong, Wei-Han; Vadivelu, Jamuna; Hassan, Hamimah

    2015-01-01

    Introduction Assessment environment, synonymous with climate or atmosphere, is multifaceted. Although there are valid and reliable instruments for measuring the educational environment, there is no validated instrument for measuring the assessment environment in medical programs. This study aimed to develop an instrument for measuring students’ perceptions of the assessment environment in an undergraduate medical program and to examine the psychometric properties of the new instrument. Method The Assessment Environment Questionnaire (AEQ), a 40-item, four-point (1=Strongly Disagree to 4=Strongly Agree) Likert scale instrument designed by the authors, was administered to medical undergraduates from the authors’ institution. The response rate was 626/794 (78.84%). To establish construct validity, exploratory factor analysis (EFA) with principal component analysis and varimax rotation was conducted. To examine the internal consistency reliability of the instrument, Cronbach's α was computed. Mean scores for the entire AEQ and for each factor/subscale were calculated. Mean AEQ scores of students from different academic years and sex were examined. Results Six hundred and eleven completed questionnaires were analysed. EFA extracted four factors: feedback mechanism (seven items), learning and performance (five items), information on assessment (five items), and assessment system/procedure (three items), which together explained 56.72% of the variance. Based on the four extracted factors/subscales, the AEQ was reduced to 20 items. Cronbach's α for the 20-item AEQ was 0.89, whereas Cronbach's α for the four factors/subscales ranged from 0.71 to 0.87. Mean score for the AEQ was 2.68/4.00. The factor/subscale of ‘feedback mechanism’ recorded the lowest mean (2.39/4.00), whereas the factor/subscale of ‘assessment system/procedure’ scored the highest mean (2.92/4.00). Significant differences were found among the AEQ scores of students from different academic

  9. Short wavelengths active bichromatic pulsed pyrometer for solids and liquids designed for measurements in harsh environments

    NASA Astrophysics Data System (ADS)

    Navello, L.; Lebedinsky, J.; Offret, J. P.; Serio, B.; Davin, T.; Bailly, Y.; Hervé, P.

    2015-05-01

    Optical passive methods for temperature measurements such as thermography or optical pyrometry are very interesting because they allow a non-intrusive measurement when the emissivity is known. The knowledge of this coefficient is critical for determining the actual temperature of a surface from the thermal radiation emitted in a wavelength band. The bichromatic pulsed pyrometer allows to overcome the knowledge of this parameter provided that precautions are taken in the choice of the values of wavelengths. When the object to be measured is placed in harsh environments, such passive optical methods are greatly disturbed by the presence of an optically absorbing medium. They are also distorted when the measured objects are located in very hot environments emitting intense disturbing radiation. In this study, we present an active bichromatic radiometric method for measuring the temperature of a surface in harsh environments. The method is based on a localized excitation by a modulated laser source in the infrared range. Detecting the temperature modulation, which is correlated with the excitation, is performed using a lock-in amplifier able to extract the signal embedded in a noise up to a million times superior. Working at short wavelengths (visible range and near infrared range) offers a large dynamic range and minimizes the error due to variations in emissivity with the wavelength. This system collects the radiation emitted by the object at a distance from a few meters up to dozens of meters depending on the configuration of the optical system. Both the principle and the design of the active bichromatic optical surface thermometer are presented and discussed. To demonstrate the method, results obtained on a molten ceramic stream are presented.

  10. On-body calibration and measurements using personal radiofrequency exposimeters in indoor diffuse and specular environments.

    PubMed

    Aminzadeh, Reza; Thielens, Arno; Bamba, Aliou; Kone, Lamine; Gaillot, Davy Paul; Lienard, Martine; Martens, Luc; Joseph, Wout

    2016-07-01

    For the first time, response of personal exposimeters (PEMs) is studied under diffuse field exposure in indoor environments. To this aim, both numerical simulations, using finite-difference time-domain method, and calibration measurements were performed in the range of 880-5875 MHz covering 10 frequency bands in Belgium. Two PEMs were mounted on the body of a human male subject and calibrated on-body in an anechoic chamber (non-diffuse) and a reverberation chamber (RC) (diffuse fields). This was motivated by the fact that electromagnetic waves in indoor environments have both specular and diffuse components. Both calibrations show that PEMs underestimate actual incident electromagnetic fields. This can be compensated by using an on-body response. Moreover, it is shown that these responses are different in anechoic chamber and RC. Therefore, it is advised to use an on-body calibration in an RC in future indoor PEM measurements where diffuse fields are present. Using the response averaged over two PEMs reduced measurement uncertainty compared to single PEMs. Following the calibration, measurements in a realistic indoor environment were done for wireless fidelity (WiFi-5G) band. Measured power density values are maximally 8.9 mW/m(2) and 165.8 μW/m(2) on average. These satisfy reference levels issued by the International Commission on Non-Ionizing Radiation Protection in 1998. Power density values obtained by applying on-body calibration in RC are higher than values obtained from no body calibration (only PEMs) and on-body calibration in anechoic room, by factors of 7.55 and 2.21, respectively. Bioelectromagnetics. 37:298-309, 2016. © 2016 Wiley Periodicals, Inc. PMID:27121268

  11. Simple instrument for measurement of remote sensing reflectance in coastal environment

    NASA Astrophysics Data System (ADS)

    Hu, Chuanmin

    2003-06-01

    Measurement of spectral remote sensing reflectance is essential to characterize water color, and to further estimate various water constituents with bio-optical algorithms. The measurement is critical to satellite data calibration/validation as well as to bio-optical algorithm development. Unfortunately, commercial instruments for such measurement are expensive, and they are either not capable of displaying data in real-time or not easy to use in coastal environment where large vessels are not applicable. In this paper we describe a simple instrument for such measurement. The fiber-optic Ocean Optics S2000 spectrometer, originally designed for lab use, was further developed to measure remote sensing reflectance. Compared with concurrent measurements from other expensive commercial instruments over different water bodies, the measured spectral reflectance is nearly identical (mean RMS difference < 2%). Through linearity and sensitivity analysis we found that it is capable of characterizing a variety of water types, even though the sensitivity is not as high as its commercial counterparts. The instrument substantially reduces the cost; it has real-time display and is easy to operate (< 0.5 kg) on small vessels. Further, combined with a liquid waveguide and a light source it is also capable of measuring Gelbstoff absorption with sufficient accuracy.

  12. Arctic (and Antarctic) Observing Experiment - an Assessment of Methods to Measure Temperature over Polar Environments

    NASA Astrophysics Data System (ADS)

    Rigor, I. G.; Clemente-Colon, P.; Nghiem, S. V.; Hall, D. K.; Woods, J. E.; Henderson, G. R.; Zook, J.; Marshall, C.; Gallage, C.

    2014-12-01

    The Arctic environment has been undergoing profound changes; the most visible is the dramatic decrease in Arctic sea ice extent (SIE). These changes pose a challenge to our ability to measure surface temperature across the Polar Regions. Traditionally, the International Arctic Buoy Programme (IABP) and International Programme for Antarctic Buoys (IPAB) have measured surface air temperature (SAT) at 2-m height, which minimizes the ambiguity of measurements near of the surface. Specifically, is the temperature sensor measuring open water, snow, sea ice, or air? But now, with the dramatic decrease in Arctic SIE, increase in open water during summer, and the frailty of the younger sea ice pack, the IABP has had to deploy and develop new instruments to measure temperature. These instruments include Surface Velocity Program (SVP) buoys, which are commonly deployed on the world's ice-free oceans and typically measure sea surface temperature (SST), and the new robust Airborne eXpendable Ice Beacons (AXIB), which measure both SST and SAT. "Best Practice" requires that these instruments are inter-compared, and early results showing differences in collocated temperature measurements of over 2°C prompted the establishment of the IABP Arctic Observing Experiment (AOX) buoy test site at the US Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) site in Barrow, Alaska. Preliminary results showed that the color of the hull of SVP buoys introduces a bias due to solar heating of the buoy. Since then, we have recommended that buoys should be painted white to reduce biases in temperature measurements due to different colors of the buoys deployed in different regions of the Arctic or the Antarctic. Measurements of SAT are more robust, but some of the temperature shields are susceptible to frosting. During our presentation we will provide an intercomparison of the temperature measurements at the AOX test site (i.e. high quality DOE/ARM observations compared with

  13. Attentional and Contextual Priors in Sound Perception

    PubMed Central

    Wolmetz, Michael; Elhilali, Mounya

    2016-01-01

    Behavioral and neural studies of selective attention have consistently demonstrated that explicit attentional cues to particular perceptual features profoundly alter perception and performance. The statistics of the sensory environment can also provide cues about what perceptual features to expect, but the extent to which these more implicit contextual cues impact perception and performance, as well as their relationship to explicit attentional cues, is not well understood. In this study, the explicit cues, or attentional prior probabilities, and the implicit cues, or contextual prior probabilities, associated with different acoustic frequencies in a detection task were simultaneously manipulated. Both attentional and contextual priors had similarly large but independent impacts on sound detectability, with evidence that listeners tracked and used contextual priors for a variety of sound classes (pure tones, harmonic complexes, and vowels). Further analyses showed that listeners updated their contextual priors rapidly and optimally, given the changing acoustic frequency statistics inherent in the paradigm. A Bayesian Observer model accounted for both attentional and contextual adaptations found with listeners. These results bolster the interpretation of perception as Bayesian inference, and suggest that some effects attributed to selective attention may be a special case of contextual prior integration along a feature axis. PMID:26882228

  14. Tuning Your Priors to the World

    PubMed Central

    Feldman, Jacob

    2013-01-01

    The idea that perceptual and cognitive systems must incorporate knowledge about the structure of the environment has become a central dogma of cognitive theory. In a Bayesian context, this idea is often realized in terms of “tuning the prior”—widely assumed to mean adjusting prior probabilities so that they match the frequencies of events in the world. This kind of “ecological” tuning has often been held up as an ideal of inference, in fact defining an “ideal observer.” But widespread as this viewpoint is, it directly contradicts Bayesian philosophy of probability, which views probabilities as degrees of belief rather than relative frequencies, and explicitly denies that they are objective characteristics of the world. Moreover, tuning the prior to observed environmental frequencies is subject to overfitting, meaning in this context overtuning to the environment, which leads (ironically) to poor performance in future encounters with the same environment. Whenever there is uncertainty about the environment—which there almost always is—an agent's prior should be biased away from ecological relative frequencies and toward simpler and more entropic priors. PMID:23335572

  15. ATK Launch Vehicle (ALV-X1) Liftoff Acoustic Environments: Prediction vs. Measurement

    NASA Technical Reports Server (NTRS)

    Houston, Janice; Counter, Douglas; Kenny, Jeremy; Murphy, John

    2009-01-01

    The ATK Launch Vehicle (ALV-X1) provided an opportunity to measure liftoff acoustic noise data. NASA Marshall Space Flight Center (MSFC) engineers were interested in the ALV-X1 launch because the First Stage motor and launch pad conditions, including a relativity short deflector ducting, provide a potential analogue to future Ares I launches. This paper presents the measured liftoff acoustics on the vehicle and tower. Those measured results are compared to predictions based upon the method described in NASA SP-8072 "Acoustic Loads Generated by the Propulsion System" and the Vehicle Acoustic Environment Prediction Program (VAEPP) which was developed by MSFC acoustics engineers. One-third octave band sound pressure levels will be presented. This data is useful for the ALV-X1 in validating the pre-launch environments and loads predictions. Additionally, the ALV-X1 liftoff data can be scaled to define liftoff environments for the NASA Constellation program Ares vehicles. Vehicle liftoff noise is caused by the supersonic jet flow interaction with surrounding atmosphere or more simply, jet noise. As the vehicle's First Stage motor is ignited, an acoustic noise field is generated by the exhaust. This noise field persists due to the supersonic jet noise and reflections from the launch pad and tower, then changes as the vehicle begins to liftoff from the launch pad. Depending on launch pad and adjacent tower configurations, the liftoff noise is generally very high near the nozzle exit and decreases rapidly away from the nozzle. The liftoff acoustic time range of interest is typically 0 to 20 seconds after ignition. The exhaust plume thermo-fluid mechanics generates sound at approx.10 Hz to 20 kHz. Liftoff acoustic noise is usually the most severe dynamic environment for a launch vehicle or payload in the mid to high frequency range (approx.50 to 2000 Hz). This noise environment can induce high-level vibrations along the external surfaces of the vehicle and surrounding

  16. Current Measurements and Overwash Monitoring Using Tilt Current Meters in Three Coastal Environments

    NASA Astrophysics Data System (ADS)

    Lowell, N. S.; Sherwood, C. R.; Decarlo, T. M.; Grant, J. R.

    2014-12-01

    Tilt Current Meters (TCMs) provide accurate, cost effective measurements of near-bottom current velocities. Many studies in coastal environments require current measurements, which are frequently made with Acoustic Doppler Profilers (ADPs). ADPs are expensive, however, and may not be suitable for locations where there is significant risk of damage, loss, or theft or where a large spatial array of measurements is required. TCMs, by contrast, are smaller, less expensive, and easier to deploy. This study tested TCMs in three sites to determine their suitability for use in research applications. TCMs are based on the drag-tilt principle, where the instrument tilts in response to current. The meter consists of a buoyant float with an onboard accelerometer, three-axis tilt sensor, three-axis magnetometer (compass), and a data logger. Current measurements are derived by post processing the tilt and compass values and converting them to velocity using empirical calibration data. Large data-storage capacity (4 GB) and low power requirements allow long deployments (many months) at high sample rates (16 Hz). We demonstrate the utility of TCM current measurements on a reef at Dongsha Atoll in the South China Sea, and in Vineyard Sound off Cape Cod, where the TCM performance was evaluated against ADP measurements. We have also used the TCM to record waves during an overwash event on a Cape Cod barrier beach during a winter storm. The TCM recorded waves as they came through the overwash channel, and the data were in agreement with the water-level record used as a reference. These tests demonstrate that TCMs may be used in a variety of near shore environments and have the potential to significantly increase the density of meters in future studies were current measurements are required.

  17. Can Less Be More? Comparison of an 8-Item Placement Quality Measure with the 50-Item Dundee Ready Educational Environment Measure (DREEM)

    ERIC Educational Resources Information Center

    Kelly, Martina; Bennett, Deirdre; Muijtjens, Arno; O'Flynn, Siun; Dornan, Tim

    2015-01-01

    Clinical clerks learn more than they are taught and not all they learn can be measured. As a result, curriculum leaders evaluate clinical educational environments. The quantitative Dundee Ready Environment Measure (DREEM) is a "de facto" standard for that purpose. Its 50 items and 5 subscales were developed by consensus. Reasoning that…

  18. Comparison of techniques for the measurement of skin temperature during exercise in a hot, humid environment.

    PubMed

    McFarlin, Bk; Venable, As; Williams, Rr; Jackson, Aw

    2015-03-01

    Exercising or working in a hot, humid environment can results in the onset of heat-related illness when an individual's temperature is not carefully monitored. The purpose of the present study was to compare three techniques (data loggers, thermal imaging, and wired electrodes) for the measurement of peripheral (bicep) and central (abdominal) skin temperature. Young men and women (N = 30) were recruited to complete the present study. The three skin temperature measurements were made at 0 and every 10-min during 40-min (60% VO2max) of cycling in a hot (39±2°C), humid (45±5% RH) environment. Data was statistically analyzed using the Bland-Altman method and correlation analysis. For abdominal skin temperature, the Bland-Altman limits of agreement indicated that data loggers (1.5) were a better index of wired than was thermal imaging (3.5), For the bicep skin temperature the limits of agreement was similar between data loggers (1.9) and thermal (1.9), suggesting the both were suitable measurements. We also found that when skin temperature exceeded 35°C, we observed progressively better prediction between data loggers, thermal imaging, and wired skin sensors. This report describes the potential for the use of data loggers and thermal imaging to be used as alternative measures of skin temperature in exercising, human subjects. PMID:25729144

  19. Acoustical environment measurement at a very shallow port: Trial case in Hashirimizu Port

    NASA Astrophysics Data System (ADS)

    Ogasawara, Hanako; Mori, Kazuyoshi

    2016-07-01

    Recently, the needs for coastal environment measurement has been increasing for many purposes, such as fishing, weather forecasting, ocean noise measurement for power plants, and coastal security. Acoustical measurement is one of the solutions because it can cover a wide area with few sensors, and it is possible to monitor long term or in real time. In this study, a small-scale reciprocal sound travel experiment was carried out in Hashirimizu Port for coastal environment measurement, such as current speed and water temperature. Since the distance between the surface and the transducer becomes short according to the tidal effect, the direct signal is canceled by the surface-reflected signal under a specific condition. However, even under such a condition, mean water temperature could be estimated from the reciprocal travel time using bottom-reflected signals. The current along the travel path was a reasonable value. It is possible to obtain a special current speed with another reciprocal path, which is in a direction perpendicular to the current travel path.

  20. Comparison of techniques for the measurement of skin temperature during exercise in a hot, humid environment

    PubMed Central

    Venable, AS; Williams, RR; Jackson, AW

    2014-01-01

    Exercising or working in a hot, humid environment can results in the onset of heat-related illness when an individual's temperature is not carefully monitored. The purpose of the present study was to compare three techniques (data loggers, thermal imaging, and wired electrodes) for the measurement of peripheral (bicep) and central (abdominal) skin temperature. Young men and women (N = 30) were recruited to complete the present study. The three skin temperature measurements were made at 0 and every 10-min during 40-min (60% VO2max) of cycling in a hot (39±2°C), humid (45±5% RH) environment. Data was statistically analyzed using the Bland-Altman method and correlation analysis. For abdominal skin temperature, the Bland-Altman limits of agreement indicated that data loggers (1.5) were a better index of wired than was thermal imaging (3.5), For the bicep skin temperature the limits of agreement was similar between data loggers (1.9) and thermal (1.9), suggesting the both were suitable measurements. We also found that when skin temperature exceeded 35°C, we observed progressively better prediction between data loggers, thermal imaging, and wired skin sensors. This report describes the potential for the use of data loggers and thermal imaging to be used as alternative measures of skin temperature in exercising, human subjects. PMID:25729144

  1. Measurement system for high-sensitivity LIBS analysis using ICCD camera in LabVIEW environment

    NASA Astrophysics Data System (ADS)

    Zaytsev, S. M.; Popov, A. M.; Zorov, N. B.; Labutin, T. A.

    2014-06-01

    A measurement system based on ultrafast (up to 10 ns time resolution) intensified CCD detector ``Nanogate-2V'' (Nanoscan, Russia) was developed for high-sensitivity analysis by Laser-Induced Breakdown Spectrometry (LIBS). LabVIEW environment provided a high level of compatibility with variety of electronic instruments and an easy development of user interface, while Visual Studio environment was used for creation of LabVIEW compatible dll library with the use of ``Nanogate-2V'' SDK. The program for camera management and laser-induced plasma spectra registration was created with the use of Call Library Node in LabVIEW. An algorithm of integration of the second device ADC ``PCI-9812'' (ADLINK) to the measurement system was proposed and successfully implemented. This allowed simultaneous registration of emission and acoustic signals under laser ablation. The measured resolving power of spectrometer-ICCD system was equal to 12000 at 632 nm. An electron density of laser plasma was estimated with the use of H-α Balmer line. Steel spectra obtained at different delays were used for selection of the optimal conditions for manganese analytical signal registration. The feature of accumulation of spectra from several laser pulses was shown. The accumulation allowed reliable observation of silver signal at 328.07 nm in the LIBS spectra of soil (CAg = 4.5 ppm). Finally, the correlation between acoustic and emission signals of plasma was found. Thus, technical possibilities of the developed LIBS system were demonstrated both for plasma diagnostics and analytical measurements.

  2. Measuring natural resource scarcity under common property environment and uncertainty: an interpretive analysis

    SciTech Connect

    Ghosh, S.N.

    1987-01-01

    In order to extract and use a natural resource (e.g., coal) the environment (air, water, etc.) must also be used as a repository of the discharged wastes (e.g., sulfur oxides, nitrous oxides, particulates, etc.). Moreover, if there is a mandated level of the environmental resource (e.g., clean air) that has to be maintained, then certain additional costs must be borne by society (firms utilizing the resource). Thus, in evaluating the scarcity of an extractible resource, the relative position of the environmental resource also must be evaluated. This study incorporated such jointness in the evaluation of the measure of resource scarcity, something earlier studies did not address. The theoretical model was developed in an optimal-control framework. It was analytically shown that this new measure of resource scarcity would indicate a different trend compared to earlier ones. The measure of resource scarcity developed in this study captures previous measures as special cases. In an uncertain world, when the impacts of use of an extractible resource on the environment is not known, the stock size of the environmental resource becomes uncertain.

  3. Measurement of the Soret coefficients for a ternary hydrocarbon mixture in low gravity environment

    NASA Astrophysics Data System (ADS)

    Ahadi, Amirhossein; Van Varenbergh, S.; Saghir, M. Ziad

    2013-05-01

    While the Soret coefficients of binary mixtures have been widely measured in the past, here we report the first measurement of the Soret coefficient of a ternary mixture in a low gravity environment on board the International Space Station. The sample was contained in a 10 mm × 10 mm × 5 mm (w, l, h) cell and was monitored by means of a Mach-Zehnder interferometer at two wavelengths. The analyzed sample was a mixture of tetrahydronaphthalene, isobutylbenzene, and dodecane at the weight fraction of 0.1/0.8/0.1. While the lateral walls of the cell did not possess complete thermal isolation, the separation of the components in the central region of the cavity was comparable to purely diffusive behavior. The same experimental parameters have been monitored in Run7 and Run12 of the Selectable Optical Diagnostics Instrument-Diffusion and Soret Coefficient experiment in order to verify the accuracy of the setup. The similarity of the results demonstrates the repeatability of thermodiffusion experiments in a microgravity environment. There was nearly equal separation of the tetrahydronaphthalene and isobutylbenzene components in opposite directions, while dodecane experienced a weak separation in the same direction as isobutylbenzene. Finally, Fourier image processing and calculations of the transient separation of the components were used to analyze the heat transfer in the system and to measure the Soret coefficients for this ternary mixture. The successful measurements shown in this work can serve as the standard for ground experiments and for numerical modeling of hydrocarbon mixtures.

  4. Measurement of the Local Food Environment: A Comparison of Existing Data Sources

    PubMed Central

    Bader, Michael D. M.; Ailshire, Jennifer A.; Morenoff, Jeffrey D.; House, James S.

    2010-01-01

    Studying the relation between the residential environment and health requires valid, reliable, and cost-effective methods to collect data on residential environments. This 2002 study compared the level of agreement between measures of the presence of neighborhood businesses drawn from 2 common sources of data used for research on the built environment and health: listings of businesses from commercial databases and direct observations of city blocks by raters. Kappa statistics were calculated for 6 types of businesses—drugstores, liquor stores, bars, convenience stores, restaurants, and grocers—located on 1,663 city blocks in Chicago, Illinois. Logistic regressions estimated whether disagreement between measurement methods was systematically correlated with the socioeconomic and demographic characteristics of neighborhoods. Levels of agreement between the 2 sources were relatively high, with significant (P < 0.001) kappa statistics for each business type ranging from 0.32 to 0.70. Most business types were more likely to be reported by direct observations than in the commercial database listings. Disagreement between the 2 sources was not significantly correlated with the socioeconomic and demographic characteristics of neighborhoods. Results suggest that researchers should have reasonable confidence using whichever method (or combination of methods) is most cost-effective and theoretically appropriate for their research design. PMID:20123688

  5. Thin Film Sensors for Minimally-Intrusive Measurements in Harsh High Temperature Environment

    NASA Technical Reports Server (NTRS)

    Lei, Jih-Fen; Will, Herbert A.; Martin, Lisa C.

    1998-01-01

    Advanced thin film sensors are being developed to provide accurate surface temperature, heat flux and strain measurements for components used in hostile propulsion environments. These sensors are sputter deposited and microfabricated directly onto the test articles with no additional bonding agent. The thickness of the sensors is only a few micrometers which creates minimal disturbance of the gas flow over the test surface. Thus thin film sensors have the advantage over conventional wire- based sensors by providing minimally intrusive measurement and having a faster response. These thin film sensors are being developed for characterization of advanced materials and structures in hostile, high-temperature environments, and for validation of design codes. This paper presents the advances of three high temperature thin film sensor technologies developed at NASA Lewis Research Center: thermocouples, heat-flux gages and strain gages. The fabrication techniques of these thin film sensors which include physical vapor deposition, photolithography patterning and lead Wire attachment are described. Sensors demonstrations on a variety of engine materials, including superalloys, ceramics and advanced ceramic matrix composites, in several hostile, high-temperature test environments are presented. The advantages and limitations of thin film sensor technology are also discussed.

  6. An approach to measuring the density of the environment of galaxies: results and comparisons with other measurements

    NASA Astrophysics Data System (ADS)

    Ortega-Minakata, R. A.; Torres-Papaqui, J. P.; Andernach, H.

    2014-10-01

    With the aim of obtaining a homogeneous and reliable measurement of the density of the environment of a large sample of galaxies, we developed a code that counts the number of neighboring galaxies around a target galaxy. As targets, we selected a large sample of 666,387 galaxies from the spectroscopic catalogue of the SDSS-DR7 with redshifts between 0.03 and 0.30 and more luminous than absolute magnitude of -19 in the SDSS r band. The photometric catalogue of the SDSS-DR7 was used to extract and count the neighboring galaxies from, including about 24M objects, also more luminous than an r-band absolute magnitude of -19, for which a photometric redshift was available to serve as a distance estimate. The code counts all galaxies within an absolute distance of 1.5 Mpc around the target (translated to an apparent radius and a redshift range around that of the target). We avoid galaxies close to the survey edges, leaving 527,074 target galaxies for which we have a measurement of environmental density. We present our results and compare them to other measurements of the density of the environment of galaxies, such as those in the MaxBCG catalogue of brightest cluster galaxies. As a control of our method, we apply it to a sample of galaxies from the 2MIG catalogue of isolated galaxies, and also to a sample of galaxies from a compilation of members of Abell clusters. We aim to use our results to test the morphology-local density relation and to study the relationship between the different types of emission-line activity of galaxies and their ambient density.

  7. The Role of Environment in the Development of Reading Skills: A Longitudinal Study of Preschool and School-Age Measures.

    ERIC Educational Resources Information Center

    Molfese, Victoria J.; Modglin, Arlene; Molfese, Dennis L.

    2003-01-01

    A longitudinal study of 113 children (ages 3-10), including 35 with poor reading skills, found both socioeconomic status, Home Observation for Measurement of the Environment scores, and reading achievement scores were related to reading abilities, but preschool environment measures were more strongly and consistently related to and predictive of…

  8. Conceptual Design and Demonstration of Space Scale for Measuring Mass in Microgravity Environment

    NASA Astrophysics Data System (ADS)

    Kim, Youn-Kyu; Lee, Joo-Hee; Choi, Gi-Hyuk; Choi, Ik-Hyeon

    2015-12-01

    In this study, a new idea for developing a space scale for measuring mass in a microgravity environment was proposed by using the inertial force properties of an object to measure its mass. The space scale detected the momentum change of the specimen and reference masses by using a load-cell sensor as the force transducer based on Newton's laws of motion. In addition, the space scale calculated the specimen mass by comparing the inertial forces of the specimen and reference masses in the same acceleration field. By using this concept, a space scale with a capacity of 3 kg based on the law of momentum conservation was implemented and demonstrated under microgravity conditions onboard International Space Station (ISS) with an accuracy of ±1 g. By the performance analysis on the space scale, it was verified that an instrument with a compact size could be implemented and be quickly measured with a reasonable accuracy under microgravity conditions.

  9. Optimization of liquid scintillation measurements applied to smears and aqueous samples collected in industrial environments

    NASA Astrophysics Data System (ADS)

    Chapon, Arnaud; Pigrée, Gilbert; Putmans, Valérie; Rogel, Gwendal

    Search for low-energy β contaminations in industrial environments requires using Liquid Scintillation Counting. This indirect measurement method supposes a fine control from sampling to measurement itself. Thus, in this paper, we focus on the definition of a measurement method, as generic as possible, for both smears and aqueous samples' characterization. That includes choice of consumables, sampling methods, optimization of counting parameters and definition of energy windows, using the maximization of a Figure of Merit. Detection limits are then calculated considering these optimized parameters. For this purpose, we used PerkinElmer Tri-Carb counters. Nevertheless, except those relative to some parameters specific to PerkinElmer, most of the results presented here can be extended to other counters.

  10. An instrument design to measure the sustainability of technology in risky environments: Case study of Iraq

    NASA Astrophysics Data System (ADS)

    Al-Sammarraie, Munadil Khaleel Faaeq; Faieq, Alaa K.; Al-Qasa, Khaled

    2016-08-01

    Electronic Government (eG) has become a vital tool to serve the beneficiaries; therefore, it has received the attention of many Information System (IS) researchers. Due to the importance of the sustainability of IS, this paper identifies the emergence of a clear gape to measure the sustainability of IS in risky circumstances, such as wars, conflicts and violence; nowadays, the risky issue is increasing remarkably. This paper expands previous studies whose focus was on investigating the sustainability of electronic services unsecured countries in the world. Consequently, a need for a specific tool to measure the sustainability of technology among the users in risky conditions has become urgent. Based on the findings, it can be confirmed that this instrument is reliable to measure the sustainability of technology in risky environments.

  11. Resolving small signal measurements in experimental plasma environments using calibrated subtraction of noise signals

    SciTech Connect

    Fimognari, P. J. Demers, D. R.; Chen, X.; Schoch, P. M.

    2014-11-15

    The performance of many diagnostic and control systems within fusion and other fields of research are often detrimentally affected by spurious noise signals. This is particularly true for those (such as radiation or particle detectors) working with very small signals. Common sources of radiated and conducted noise in experimental fusion environments include the plasma itself and instrumentation. The noise complicates data analysis, as illustrated by noise on signals measured with the heavy ion beam probe (HIBP) installed on the Madison Symmetric Torus. The noise is time-varying and often exceeds the secondary ion beam current (in contrast with previous applications). Analysis of the noise identifies the dominant source as photoelectric emission from the detectors induced by ultraviolet light from the plasma. This has led to the development of a calibrated subtraction technique, which largely removes the undesired temporal noise signals from data. The advantages of the technique for small signal measurement applications are demonstrated through improvements realized on HIBP fluctuation measurements.

  12. Design of a Multisensory Probe for Measuring Carbon Cycle Processes in Aqueous Subterranean Environments

    SciTech Connect

    McIntyre, Timothy J; Kisner, Roger; Woodworth, Ken; Lenarduzzi, Roberto; Frank, Steven Shane; McKnight, Timothy E

    2015-01-01

    The global carbon cycle describes the exchange of carbon between the atmosphere, terrestrial vegetation, oceans, and soil. Mechanisms involving carbon in sub-terrestrial ecosystems and their impact on climate are not well understood. This lack of understanding limits current climate models and prevents accurate soil-carbon storage predications for future climate conditions. To address the lack of instrumentation for conducting high fidelity measurements of appropriate parameters in the field, a multi-sensory probe using a mix of optical, fiber optic, and electronic technologies to measure CO2, temperature, dissolved oxygen, redox potential, and water level in subsurface environments has been developed. Details of the design, fabrication and laboratory performance verification are presented. Use cases and the anticipated impacts of such measurements on climate models are discussed.

  13. Measurement of neutron spectra in varied environments by the foil-activation method with arbitrary trials

    SciTech Connect

    Kelly, J.G.; Vehar, D.W.

    1987-12-01

    Neutron spectra have been measured by the foil-activation method in 13 different environments in and around the Sandia Pulsed Reactor, the White Sands Missile Range Fast Burst Reactor, and the Sandia Annular Core Research Reactor. The spectra were obtained by using the SANDII code in a manner that was not dependent on the initial trial. This altered technique is better suited for the determination of spectra in environments that are difficult to predict by calculation, and it tends to reveal features that may be biased out by the use of standard trial-dependent methods. For some of the configurations, studies have also been made of how well the solution is determined in each energy region. The experimental methods and the techniques used in the analyses are thoroughly explained. 34 refs., 51 figs., 40 tabs.

  14. Subjective versus objective measures of tic severity in Tourette syndrome - The influence of environment.

    PubMed

    Barnea, Meirav; Benaroya-Milshtein, Noa; Gilboa-Sechtman, Eva; Woods, Douglas W; Piacentini, John; Fennig, Silvana; Apter, Alan; Steinberg, Tamar

    2016-08-30

    The objective of this study was to examine the influence of environmental challenges on tic expression by subjective and objective measures. The study group consisted of 41 children aged 6-18 years (M=10.15, SD=2.73) with a primary diagnosis of Tourette syndrome. Subjective measures included the Functional Assessment Interview developed for this study and three standard validated instruments. The objective measure was a video-recording of the patients in five daily-life situations: watching television, doing homework, being alone, receiving attention when ticcing, and talking to a stranger. In addition, the effect of premonitory urges on assessment of tic expression was evaluated. The associations between the subjective and objective measures of tic expression were moderate to low. A significantly higher number of tics were observed in the television situation, and a significantly lower number in the alone situation, compared to the other situations. Higher levels of premonitory urge were associated with greater awareness of objectively measured tic expression. In conclusion, tic expression is significantly influenced by the environment. Subjective measures of tic expression may be misleading. These results have implications for refining the clinical assessment of tics, improving research methodology, and developing new therapeutic strategies. PMID:27289326

  15. A dynamic technique for measuring surface tension at high temperatures in microgravity environment

    NASA Technical Reports Server (NTRS)

    Miiller, A. P.; Cezairliyan, A.

    1990-01-01

    The feasibility of a dynamic technique for measuring surface tension of liquid metals at high temperatures in a microgravity environment was demonstrated. The basic method involves heating a tubular specimen resistively from ambient temperature through its melting point in about 1 sec by passing an electrical current pulse through it, while simultaneously recording the pertinent experimental quantities. Static equilibrium for the molten specimen is achieved in a microgravity environment by splitting the current after it passes through the specimen tube and returning a fraction along the tube axis, and the remaining fraction outside the specimen. Adjustments to the current split enable a balance between the magnetic and surface tension forces acting on the specimen. Values for surface tension are determined from measurements of the equilibrium dimensions of the molten specimen tube, and the magnitudes of the currents. Rapid melting experiments, performed during microgravity simulations with the NASA KC-135 aircraft, yield a value for the surface tension of copper at its melting point which is in agreement with literature data. Measurements of surface tension of a refractory metal (tantalum) are underway.

  16. A clean radiation environment for opacity measurements of radiatively heated material

    SciTech Connect

    Xu Yan; Zhang Jinyan; Yang Jiamin; Pei Wenbing; Ding Yongkun; Lai Donxian; Men Guangwei; Luo Zheng

    2007-05-15

    A clean x-ray radiation environment is essential for detailed measurements of the opacity of high-temperature radiatively heated material. A lot of laser energy is usually needed to heat a large hohlraum to produce such a clean x-ray radiation environment. A type of target is proposed that uses low-density, low-Z foam to provide a passage to radiation while isolating the sample from the disturbance from laser produced, high-temperature, high-Z plasma and heating by reflected laser light. With a smaller hohlraum, less laser energy is needed to produce high-temperature x-ray radiation for sample heating. Experiments have been done to check the proposal. The recorded clean Al self-emission spectra proved there was no gold plasma in the view-way to disturb the measurement. This type of hohlraum can provide a high-quality work-table for opacity measurement even in a relatively small laser facility.

  17. The School Assessment for Environmental Typology (SAfETy): An Observational Measure of the School Environment.

    PubMed

    Bradshaw, Catherine P; Milam, Adam J; Furr-Holden, C Debra M; Johnson, Sarah Lindstrom

    2015-12-01

    School safety is of great concern for prevention researchers, school officials, parents, and students, yet there are a dearth of assessments that have operationalized school safety from an organizational framework using objective tools and measures. Such a tool would be important for deriving unbiased assessments of the school environment, which in turn could be used as an evaluative tool for school violence prevention efforts. The current paper presents a framework for conceptualizing school safety consistent with Crime Prevention through Environmental Design (CPTED) model and social disorganization theory, both of which highlight the importance of context as a driver for adolescents' risk for involvement in substance use and violence. This paper describes the development of a novel observational measure, called the School Assessment for Environmental Typology (SAfETy), which applies CPTED and social disorganizational frameworks to schools to measure eight indicators of school physical and social environment (i.e., disorder, trash, graffiti/vandalism, appearance, illumination, surveillance, ownership, and positive behavioral expectations). Drawing upon data from 58 high schools, we provide preliminary data regarding the validity and reliability of the SAfETy and describe patterns of the school safety indicators. Findings demonstrate the reliability and validity of the SAfETy and are discussed with regard to the prevention of violence in schools. PMID:26296310

  18. Multiparameter Flowfield Measurements in High-Pressure, Cryogenic Environments Using Femtosecond Lasers

    NASA Technical Reports Server (NTRS)

    Burns, Ross A.; Danehy, Paul M.; Peters, Christopher J.

    2016-01-01

    Femtosecond laser electronic excitation tagging (FLEET) and Rayleigh scattering (RS) from a femtosecond laser are demonstrated in the NASA Langley 0.3-m Transonic Cryogenic Tunnel (TCT). The measured signals from these techniques are examined for their thermodynamic dependencies in pure nitrogen. The FLEET signal intensity and signal lifetimes are found to scale primarily with the gas density, as does the RS signal. Several models are developed, which capture these physical behaviors. Notably, the FLEET and Rayleigh scattering intensities scale linearly with the flow density, while the FLEET signal decay rates are a more complex function of the thermodynamic state of the gas. The measurement of various flow properties are demonstrated using these techniques. While density was directly measured from the signal intensities and FLEET signal lifetime, temperature and pressure were measured using the simultaneous FLEET velocity measurements while assuming the flow had a constant total enthalpy. Measurements of density, temperature, and pressure from the FLEET signal are made with accuracies as high as 5.3 percent, 0.62 percent, and 6.2 percent, respectively, while precisions were approximately 10 percent, 0.26 percent, and 11 percent for these same quantities. Similar measurements of density from Rayleigh scattering showed an overall accuracy of 3.5 percent and a precision of 10.2 percent over a limited temperature range (T greater than 195 K). These measurements suggest a high degree of utility at using the femtosecond-laser based diagnostics for making multiparameter measurements in high-pressure, cryogenic environments such as large-scale TCT facilities.

  19. Ultrasonic techniques for measuring physical properties of fluids in harsh environments

    NASA Astrophysics Data System (ADS)

    Pantea, Cristian

    Ultrasonic-based measurement techniques, either in the time domain or in the frequency domain, include a wide range of experimental methods for investigating physical properties of materials. This discussion is specifically focused on ultrasonic methods and instrumentation development for the determination of liquid properties at conditions typically found in subsurface environments (in the U.S., more than 80% of total energy needs are provided by subsurface energy sources). Such sensors require materials that can withstand harsh conditions of high pressure, high temperature and corrosiveness. These include the piezoelectric material, electrically conductive adhesives, sensor housings/enclosures, and the signal carrying cables, to name a few. A complete sensor package was developed for operation at high temperatures and pressures characteristic to geothermal/oil-industry reservoirs. This package is designed to provide real-time, simultaneous measurements of multiple physical parameters, such as temperature, pressure, salinity and sound speed. The basic principle for this sensor's operation is an ultrasonic frequency domain technique, combined with transducer resonance tracking. This multipurpose acoustic sensor can be used at depths of several thousand meters, temperatures up to 250 °C, and in a very corrosive environment. In the context of high precision measurement of sound speed, the determination of acoustic nonlinearity of liquids will also be discussed, using two different approaches: (i) the thermodynamic method, in which precise and accurate frequency domain sound speed measurements are performed at high pressure and high temperature, and (ii) a modified finite amplitude method, requiring time domain measurements of the second harmonic at room temperature. Efforts toward the development of an acoustic source of collimated low-frequency (10-150 kHz) beam, with applications in imaging, will also be presented.

  20. Measuring the Emissivity of Samples in an Airless-Body Environment: Improvements, Results and Error Analysis

    NASA Astrophysics Data System (ADS)

    Thomas, I.; Bowles, N. E.; Greenhagen, B. T.; Donaldson Hanna, K. L.

    2013-12-01

    One of the key requirements for deriving surface properties from remote sensing instruments is to have a library of equivalent measurements of known samples. In the thermal infrared, constructing a spectral library for airless bodies such as the Moon and asteroids is complicated by the thermal environment present on these bodies, which can generate significant temperature gradients in the top millimetre of the sample. Such gradients can alter thermal infrared spectra, and therefore these conditions must be simulated in the laboratory to produce equivalent results to those of remote sensing instruments. We have constructed an experiment to achieve this, consisting of: (1) a chamber capable of maintaining a pressure of 1 x 10-5 mbar, (2) a solar-like halogen lamp to replicate surface heating by solar radiation, (3) a temperature controlled sample cup to provide equivalent at-depth heating, (4) a high-emissivity radiation shield, cooled to <150K, to simulate cold space, and (5) a Brüker IFS66v Fourier Transform Spectrometer, taking spectra from 2500-400cm-1 with 2cm-1 resolution. Meteorite, Apollo, terrestrial, and artificially weathered samples have all been measured recently in the chamber, which has required us to make some significant improvements in the design and calibration of the chamber, such as the addition of an intermediate calibration target, measured immediately before and after each sample, and a full examination of calibration errors. Monte Carlo analysis has been used to quantify the absolute uncertainty in the measured spectra, to investigate the extent to which small shifts in spectra can be attributed to the thermal environment over measurement uncertainty, allowing accurate error bars to be added to lunar emissivity spectra for the first time. Schematic of the airless-body simulation chamber, showing the main parts. The calibration target is moved into place via a linear actuator driven by a magnetic coupling.

  1. Detecting band inversions by measuring the environment: fingerprints of electronic band topology in bulk phonon linewidths

    NASA Astrophysics Data System (ADS)

    Saha, Kush; Legare, Katherine; Garate, Ion

    The interplay between topological phases of matter and dissipative baths constitutes an emergent research topic with links to condensed matter, photonic crystals, cold atomic gases and quantum information. While recent studies suggest that dissipative baths can induce topological phases in intrinsically trivial quantum materials, the backaction of topological invariants on dissipative baths is overlooked. By exploring this back action for a centrosymmetric Dirac insulator coupled to phonons, we show that the linewidths of bulk optical phonons can reveal electronic band inversions. This result is the first known example where topological phases of an open quantum system may be detected by measuring the bulk properties of the surrounding environment.

  2. Family and School Psychosocial Environment (FSPE): development of a brief questionnaire measuring perceived psychosocial environments in children/siblings.

    PubMed

    Persson, Bertil

    2011-06-01

    The aim of the study was to develop a short Swedish standardized, factor analyzed and cross-validated, family and school psychosocial environment questionnaire (FSPE). The study was based on 244 Swedish girls and boys, 10-19 years old, who filled in the FSPE. Maximum likelihood factor analysis, promax rotation, yielded six primary factors, based on absolute ratings. Since the factors were somewhat correlated, two broader secondary factors, with satisfactory reliabilities, were also included in the form, named Warmth, support and openness from parents, siblings and peers, and Family conflicts and school discipline, respectively. Means and standard deviations for girls and boys showed sex differences in most of the factors. Because the children participated anonymously they could report about spanking without negative consequences. Indeed, 8.1% of the children had been spanked by their parents. Based on relative ratings, two factors were identified, covering environmental questions about "more than, the same as or less than" a sibling. Only 6.6% of the children rated their environment exactly the same on the Family Psychosocial Environment (FPE) factors, compared to a sibling within the family. Thus the majority reported environmental differences. Further research is proposed to evaluate such differences and relations to personality, genotype-environment correlation and genetic mediation. PMID:21332485

  3. The light spot test: Measuring anxiety in mice in an automated home-cage environment.

    PubMed

    Aarts, Emmeke; Maroteaux, Gregoire; Loos, Maarten; Koopmans, Bastijn; Kovačević, Jovana; Smit, August B; Verhage, Matthijs; Sluis, Sophie van der

    2015-11-01

    Behavioral tests of animals in a controlled experimental setting provide a valuable tool to advance understanding of genotype-phenotype relations, and to study the effects of genetic and environmental manipulations. To optimally benefit from the increasing numbers of genetically engineered mice, reliable high-throughput methods for comprehensive behavioral phenotyping of mice lines have become a necessity. Here, we describe the development and validation of an anxiety test, the light spot test, that allows for unsupervised, automated, high-throughput testing of mice in a home-cage system. This automated behavioral test circumvents bias introduced by pretest handling, and enables recording both baseline behavior and the behavioral test response over a prolonged period of time. We demonstrate that the light spot test induces a behavioral response in C57BL/6J mice. This behavior reverts to baseline when the aversive stimulus is switched off, and is blunted by treatment with the anxiolytic drug Diazepam, demonstrating predictive validity of the assay, and indicating that the observed behavioral response has a significant anxiety component. Also, we investigated the effectiveness of the light spot test as part of sequential testing for different behavioral aspects in the home-cage. Two learning tests, administered prior to the light spot test, affected the light spot test parameters. The light spot test is a novel, automated assay for anxiety-related high-throughput testing of mice in an automated home-cage environment, allowing for both comprehensive behavioral phenotyping of mice, and rapid screening of pharmacological compounds. PMID:26072393

  4. Effects of the Physical Work Environment on Physiological Measures of Stress

    PubMed Central

    Thayer, J. F.; Verkuil, B.; Brosschot, J. F.; Kampschroer, K.; West, A.; Sterling, C.; Christie, I.C.; Abernethy, D.; Sollers, J. J.; Cizza, G.; Marques, A. H.; Sternberg, E. M.

    2010-01-01

    Aims In this study we investigated the effects of the physical work environment on two physiological measures of the stress response. Methods and Results Circadian variations in vagally mediated HRV and the morning rise in cortisol were evaluated in sixty participants working in a government building either in a traditional (individual offices and old cubicles; n=40) or a modern workspace (individualized cubicles with improved views and lighting; n=20). Results revealed significant linear (B = −1.03; CI: −1.05 to −1.01, p < .05) and quadratic (B = 1.001; CI: 1.0004 to 1.002, p < .05) trends by office type interactions for indices of vagally mediated HRV. Individuals in the old office space had flatter slopes and thus less circadian variation including less HRV at night, and a larger rise in cortisol upon awakening compared to those in the new office space. Conclusions These results indicate that physical features of the work environment may affect two aspects of the physiological stress response: circadian variations in HRV and the morning rise in cortisol. These findings have important social, economic, and public health implications for work environment risk factors on health. PMID:20404733

  5. In-situ measurements of the secondary electron yield in an accelerator environment: Instrumentation and methods

    NASA Astrophysics Data System (ADS)

    Hartung, W. H.; Asner, D. M.; Conway, J. V.; Dennett, C. A.; Greenwald, S.; Kim, J.-S.; Li, Y.; Moore, T. P.; Omanovic, V.; Palmer, M. A.; Strohman, C. R.

    2015-05-01

    The performance of a particle accelerator can be limited by the build-up of an electron cloud (EC) in the vacuum chamber. Secondary electron emission from the chamber walls can contribute to EC growth. An apparatus for in-situ measurements of the secondary electron yield (SEY) in the Cornell Electron Storage Ring (CESR) was developed in connection with EC studies for the CESR Test Accelerator program. The CESR in-situ system, in operation since 2010, allows for SEY measurements as a function of incident electron energy and angle on samples that are exposed to the accelerator environment, typically 5.3 GeV counter-rotating beams of electrons and positrons. The system was designed for periodic measurements to observe beam conditioning of the SEY with discrimination between exposure to direct photons from synchrotron radiation versus scattered photons and cloud electrons. The samples can be exchanged without venting the CESR vacuum chamber. Measurements have been done on metal surfaces and EC-mitigation coatings. The in-situ SEY apparatus and improvements to the measurement tools and techniques are described.

  6. Establishing aeolian particulate 'fingerprints' in an airport environment using magnetic measurements and SEM/EDAX

    NASA Astrophysics Data System (ADS)

    Jones, Sue; Hoon, Stephen R.; Richardson, Nigel; Bennett, Michael

    2016-04-01

    The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of particulate matter (PM) from aviation activity on health and the environment. PM within the airport environment, in particular, may be derived from a wide range of potential sources including aircraft; vehicles; ground support equipment and buildings. In order to investigate and remediate potential problem sources, it is important to be able to identify characteristic particulate 'fingerprints' which would allow source attribution, particularly respirable particulates. To date the identification of such 'fingerprints' has remained elusive but remains a key research priority for the aviation industry (Webb et al, 2008). In previous PM studies, environmental magnetism has been used as a successful technique for discriminating between different emission types and particulate sources in both urban and industrial environments (e.g. Hunt et al 1984; Lecoanet et al 2003, Jones et al 2015). Environmental magnetism is a non-destructive and relatively rapid technique involving the use of non-directional, rock magnetic measurements to characterise the mineral magnetic properties of natural and anthropogenic materials. In other studies scanning electron microscopy (SEM) has also been used as an effective characterisation technique for the investigation of grain size and morphology of PM derived from vehicle emissions (e.g. Bucko et al 2010) and fossil fuel combustion sources (Kim et al 2009). In this study, environmental magnetic measurements and SEM/EDAX have been used to characterise dusts from specific aircraft sources including engines, brakes and tyres. Furthermore, these methods have also been applied to runway (both hard and grass covered surfaces), taxiway and apron dusts collected during extensive environmental sampling at Manchester International Airport, UK in order to

  7. An autonomous in situ detection system for radioactivity measurements in the marine environment.

    PubMed

    Tsabaris, C; Bagatelas, C; Dakladas, Th; Papadopoulos, C T; Vlastou, R; Chronis, G T

    2008-10-01

    A new detection system named "KATERINA" is developed and applied for measuring marine radioactivity using NaI(Tl) as a crystal. This apparatus is designed for qualitative and quantitative radionuclide detection in the marine environment with maximum depth of deployment 400 m. A detailed study for the enclosure of the system and for the electronics development is performed. The system offers volumetric activities in Bq/m(3) using the marine efficiency calibration, which is measured by dilution of three reference sources ((99m)Tc, (137)Cs, and (40)K) in a special tank. The calibration procedures for energy, energy resolution and efficiency were analyzed with particular attention to the factors that affect the calibration parameters. The underwater detector is tested in the field for acquiring radon daughters ((214)Pb and (214)Bi) in a region where submarine groundwater discharge exists in the coastal zone. PMID:18372182

  8. Conceptualizing and Comparing Neighborhood and Activity Space Measures for Food Environment Research

    PubMed Central

    Crawford, Thomas W.; Pitts, Stephanie B. Jilcott; McGuirt, Jared T.; Keyserling, Thomas C.; Ammerman, Alice S.

    2014-01-01

    Greater accessibility to geospatial technologies has led to a surge of spatialized public health research, much of which has focused on food environments. The purpose of this study was to analyze differing spatial measures of exposure to supermarkets and farmers’ markets among women of reproductive age in eastern North Carolina. Exposure measures were derived using participant-defined neighborhoods, investigator-defined road network neighborhoods, and activity spaces incorporating participants’ time space behaviors. Results showed that mean area for participant-defined neighborhoods (0.04 sq. miles) was much smaller than 2.0 mile road network neighborhoods (3.11 sq. miles) and activity spaces (26.36 sq. miles), and that activity spaces provided the greatest market exposure. The traditional residential neighborhood concept may not be particularly relevant for all places. Time-space approaches capturing activity space may be more relevant, particularly if integrated with mixed methods strategies. PMID:25306420

  9. How Natural Water Retention Measures (NWRM) can help rural and urban environments improve their resilience?

    NASA Astrophysics Data System (ADS)

    Siauve, Sonia

    2016-04-01

    The challenges related to water resources management are exacerbated by climate change which implies additional complexity and uncertainty. The impacts of climate change have thus to be taken into account, from today on the next decades, to ensure a sustainable integrated water resources management. One of the main environmental objective of the Water Framework Directive (2000/30/CE) was to achieve and maintain a good status for all water bodies by the target date of 2015. Unfortunately, Member States didn't manage to reach this goal and in this context, the European Commission (EC), since many years, have started many initiatives and reforms to improve the global situation. In 2012 the DG Environment (DGENV) of the EC published a "Blueprint to safeguard Europe's water resources" that states the need for further implementation of water resource management measures and in particular Natural Water Retention Measures (NWRMs). NWRM are measures that aim to safeguard and enhance the water storage potential of landscape, soils and aquifers, by restoring ecosystems, natural features and characteristics of water courses, and by using natural processes. They are Nature-Based Solutions supporting adaptation and reducing vulnerability of water resources. Their interest lies with the multiple benefits they can deliver, and their capacity to contribute simultaneously to the achievement of the objectives of different European policies (WFD, FD, Biodiversity strategy …). However the knowledge on NWRM is scattered and addressed differently in the countries, whereas the NWRM potential for improving the state of the environment and resilience (drought, flood, biodiversity…) in a changing environment is high. In 2013, all EU countries started the elaboration of the second River Basin Management Plan and associated Programme of Measures. To support MS authorities and local implementers of these measures DGENV launched a 14 month project for collaboratively building knowledge and

  10. Dynamic emotion perception and prior expectancy.

    PubMed

    Dzafic, Ilvana; Martin, Andrew K; Hocking, Julia; Mowry, Bryan; Burianová, Hana

    2016-06-01

    Social interactions require the ability to rapidly perceive emotion from various incoming dynamic, multisensory cues. Prior expectations reduce incoming emotional information and direct attention to cues that are aligned with what is expected. Studies to date have investigated the prior expectancy effect using static emotional images, despite the fact that dynamic stimuli would represent greater ecological validity. The objective of the study was to create a novel functional magnetic resonance imaging (fMRI) paradigm to examine the influence of prior expectations on naturalistic emotion perception. For this purpose, we developed a dynamic emotion perception task, which consisted of audio-visual videos that carry emotional information congruent or incongruent with prior expectations. The results show that emotional congruency was associated with activity in prefrontal regions, amygdala, and putamen, whereas emotional incongruency was associated with activity in temporoparietal junction and mid-cingulate gyrus. Supported by the behavioural results, our findings suggest that prior expectations are reinforced after repeated experience and learning, whereas unexpected emotions may rely on fast change detection processes. The results from the current study are compatible with the notion that the ability to automatically detect unexpected changes in complex dynamic environments allows for adaptive behaviours in potentially advantageous or threatening situations. PMID:27126841

  11. Recommendations for Guidelines for Environment-Specific Magnetic-Field Measurements, Rapid Program Engineering Project #2

    SciTech Connect

    Electric Research and Management, Inc.; IIT Research Institute; Magnetic Measurements; Survey Research Center, University of California; T. Dan Bracken, Inc.

    1997-03-11

    The purpose of this project was to document widely applicable methods for characterizing the magnetic fields in a given environment, recognizing the many sources co-existing within that space. The guidelines are designed to allow the reader to follow an efficient process to (1) plan the goals and requirements of a magnetic-field study, (2) develop a study structure and protocol, and (3) document and carry out the plan. These guidelines take the reader first through the process of developing a basic study strategy, then through planning and performing the data collection. Last, the critical factors of data management, analysis reporting, and quality assurance are discussed. The guidelines are structured to allow the researcher to develop a protocol that responds to specific site and project needs. The Research and Public Information Dissemination Program (RAPID) is based on exposure to magnetic fields and the potential health effects. Therefore, the most important focus for these magnetic-field measurement guidelines is relevance to exposure. The assumed objective of an environment-specific measurement is to characterize the environment (given a set of occupants and magnetic-field sources) so that information about the exposure of the occupants may be inferred. Ideally, the researcher seeks to obtain complete or "perfect" information about these magnetic fields, so that personal exposure might also be modeled perfectly. However, complete data collection is not feasible. In fact, it has been made more difficult as the research field has moved to expand the list of field parameters measured, increasing the cost and complexity of performing a measurement and analyzing the data. The guidelines address this issue by guiding the user to design a measurement protocol that will gather the most exposure-relevant information based on the locations of people in relation to the sources. We suggest that the "microenvironment" become the base unit of area in a study, with

  12. Advanced Liquid-Free, Piezoresistive, SOI-Based Pressure Sensors for Measurements in Harsh Environments.

    PubMed

    Ngo, Ha-Duong; Mukhopadhyay, Biswaijit; Ehrmann, Oswin; Lang, Klaus-Dieter

    2015-01-01

    In this paper we present and discuss two innovative liquid-free SOI sensors for pressure measurements in harsh environments. The sensors are capable of measuring pressures at high temperatures. In both concepts media separation is realized using a steel membrane. The two concepts represent two different strategies for packaging of devices for use in harsh environments and at high temperatures. The first one is a "one-sensor-one-packaging_technology" concept. The second one uses a standard flip-chip bonding technique. The first sensor is a "floating-concept", capable of measuring pressures at temperatures up to 400 °C (constant load) with an accuracy of 0.25% Full Scale Output (FSO). A push rod (mounted onto the steel membrane) transfers the applied pressure directly to the center-boss membrane of the SOI-chip, which is placed on a ceramic carrier. The chip membrane is realized by Deep Reactive Ion Etching (DRIE or Bosch Process). A novel propertied chip housing employing a sliding sensor chip that is fixed during packaging by mechanical preloading via the push rod is used, thereby avoiding chip movement, and ensuring optimal push rod load transmission. The second sensor can be used up to 350 °C. The SOI chips consists of a beam with an integrated centre-boss with was realized using KOH structuring and DRIE. The SOI chip is not "floating" but bonded by using flip-chip technology. The fabricated SOI sensor chip has a bridge resistance of 3250 Ω. The realized sensor chip has a sensitivity of 18 mV/µm measured using a bridge current of 1 mA. PMID:26295235

  13. Designing virtual environments to measure behavioral correlates of state-level body satisfaction.

    PubMed

    Purvis, Clare K; Jones, Megan; Bailey, Jakki; Bailenson, Jeremy; Taylor, C Barr

    2013-01-01

    Virtual reality (VR) offers a unique method for eliciting state-variable fluctuations in body satisfaction and associated behaviors by allowing near-perfect control over environmental factors. Greater variability in momentary body satisfaction is associated with more problematic eating behavior and cognitive styles predictive of eating disorders. The field currently lacks a model for understanding environmental variables and everyday events that tend to influence fluctuations in state body satisfaction. This study proposes a model of state-level body satisfaction and presents a method for measuring changes as they occur. We aim to investigate body comparison, selective attention and body checking behaviors in relation to self-report levels of state body satisfaction. We additionally assess interpersonal correlates of state body satisfaction using VR to measure personal distance between subjects and avatars of varying body sizes. 80 female college students with varying levels of weight and shape concerns will be exposed to five virtual environments designed to elicit varying levels of body dissatisfaction: (a) an empty room; (b) an empty beach; (c) a beach populated with avatars; (d) an empty party scene; (e) a party scene populated with avatars. Self-report body satisfaction was measured immediately following each exposure. A tracking system automatically tracked subjects' head orientation and body translation to measure visual gaze and personal space behavior relative to each virtual human within the environment. Data collection is currently underway and expected to be completed by May 2013. Preliminary data and development of the VR model for state-variable assessment will be presented. PMID:23792867

  14. Advanced Liquid-Free, Piezoresistive, SOI-Based Pressure Sensors for Measurements in Harsh Environments

    PubMed Central

    Ngo, Ha-Duong; Mukhopadhyay, Biswaijit; Ehrmann, Oswin; Lang, Klaus-Dieter

    2015-01-01

    In this paper we present and discuss two innovative liquid-free SOI sensors for pressure measurements in harsh environments. The sensors are capable of measuring pressures at high temperatures. In both concepts media separation is realized using a steel membrane. The two concepts represent two different strategies for packaging of devices for use in harsh environments and at high temperatures. The first one is a “one-sensor-one-packaging_technology” concept. The second one uses a standard flip-chip bonding technique. The first sensor is a “floating-concept”, capable of measuring pressures at temperatures up to 400 °C (constant load) with an accuracy of 0.25% Full Scale Output (FSO). A push rod (mounted onto the steel membrane) transfers the applied pressure directly to the center-boss membrane of the SOI-chip, which is placed on a ceramic carrier. The chip membrane is realized by Deep Reactive Ion Etching (DRIE or Bosch Process). A novel propertied chip housing employing a sliding sensor chip that is fixed during packaging by mechanical preloading via the push rod is used, thereby avoiding chip movement, and ensuring optimal push rod load transmission. The second sensor can be used up to 350 °C. The SOI chips consists of a beam with an integrated centre-boss with was realized using KOH structuring and DRIE. The SOI chip is not “floating” but bonded by using flip-chip technology. The fabricated SOI sensor chip has a bridge resistance of 3250 Ω. The realized sensor chip has a sensitivity of 18 mV/µm measured using a bridge current of 1 mA. PMID:26295235

  15. Measurement of the Soret coefficients for a ternary hydrocarbon mixture in low gravity environment.

    PubMed

    Ahadi, Amirhossein; Varenbergh, S Van; Saghir, M Ziad

    2013-05-28

    While the Soret coefficients of binary mixtures have been widely measured in the past, here we report the first measurement of the Soret coefficient of a ternary mixture in a low gravity environment on board the International Space Station. The sample was contained in a 10 mm × 10 mm × 5 mm (w, l, h) cell and was monitored by means of a Mach-Zehnder interferometer at two wavelengths. The analyzed sample was a mixture of tetrahydronaphthalene, isobutylbenzene, and dodecane at the weight fraction of 0.1∕0.8∕0.1. While the lateral walls of the cell did not possess complete thermal isolation, the separation of the components in the central region of the cavity was comparable to purely diffusive behavior. The same experimental parameters have been monitored in Run7 and Run12 of the Selectable Optical Diagnostics Instrument-Diffusion and Soret Coefficient experiment in order to verify the accuracy of the setup. The similarity of the results demonstrates the repeatability of thermodiffusion experiments in a microgravity environment. There was nearly equal separation of the tetrahydronaphthalene and isobutylbenzene components in opposite directions, while dodecane experienced a weak separation in the same direction as isobutylbenzene. Finally, Fourier image processing and calculations of the transient separation of the components were used to analyze the heat transfer in the system and to measure the Soret coefficients for this ternary mixture. The successful measurements shown in this work can serve as the standard for ground experiments and for numerical modeling of hydrocarbon mixtures. PMID:23742467

  16. Measuring the food environment: a systematic technique for characterizing food stores using display counts.

    PubMed

    Miller, Cassandra; Bodor, J Nicholas; Rose, Donald

    2012-01-01

    Marketing research has documented the influence of in-store characteristics-such as the number and placement of display stands-on consumer purchases of a product. However, little information exists on this topic for key foods of interest to those studying the influence of environmental changes on dietary behavior. This study demonstrates a method for characterizing the food environment by measuring the number of separate displays of fruits, vegetables, and energy-dense snack foods (including chips, candies, and sodas) and their proximity to cash registers in different store types. Observations in New Orleans stores (N = 172) in 2007 and 2008 revealed significantly more displays of energy-dense snacks than of fruits and vegetables within all store types, especially supermarkets. Moreover, supermarkets had an average of 20 displays of energy-dense snacks within 1 meter of their cash registers, yet none of them had even a single display of fruits or vegetables near their cash registers. Measures of the number of separate display stands of key foods and their proximity to a cash register can be used by researchers to better characterize food stores and by policymakers to address improvements to the food environment. PMID:22701497

  17. Measuring the Food Environment: A Systematic Technique for Characterizing Food Stores Using Display Counts

    PubMed Central

    Miller, Cassandra; Bodor, J. Nicholas; Rose, Donald

    2012-01-01

    Marketing research has documented the influence of in-store characteristics—such as the number and placement of display stands—on consumer purchases of a product. However, little information exists on this topic for key foods of interest to those studying the influence of environmental changes on dietary behavior. This study demonstrates a method for characterizing the food environment by measuring the number of separate displays of fruits, vegetables, and energy-dense snack foods (including chips, candies, and sodas) and their proximity to cash registers in different store types. Observations in New Orleans stores (N = 172) in 2007 and 2008 revealed significantly more displays of energy-dense snacks than of fruits and vegetables within all store types, especially supermarkets. Moreover, supermarkets had an average of 20 displays of energy-dense snacks within 1 meter of their cash registers, yet none of them had even a single display of fruits or vegetables near their cash registers. Measures of the number of separate display stands of key foods and their proximity to a cash register can be used by researchers to better characterize food stores and by policymakers to address improvements to the food environment. PMID:22701497

  18. LP DAAC MEaSUREs Project Artifact Tracking Via the NASA Earthdata Collaboration Environment

    NASA Astrophysics Data System (ADS)

    Bennett, S. D.

    2015-12-01

    The Land Processes Distributed Active Archive Center (LP DAAC) is a NASA Earth Observing System (EOS) Data and Information System (EOSDIS) DAAC that supports selected EOS Community non-standard data products such as the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Emissivity Database (GED), and also supports NASA Earth Science programs such as Making Earth System Data Records for Use in Research Environments (MEaSUREs) to contribute in providing long-term, consistent, and mature data products. As described in The LP DAAC Project Lifecycle Plan (Daucsavage, J.; Bennett, S., 2014), key elements within the Project Inception Phase fuse knowledge between NASA stakeholders, data producers, and NASA data providers. To support and deliver excellence for NASA data stewardship, and to accommodate long-tail data preservation with Community and MEaSUREs products, the LP DAAC is utilizing NASA's own Earthdata Collaboration Environment to bridge stakeholder communication divides. By leveraging a NASA supported platform, this poster describes how the Atlassian Confluence software combined with a NASA URS/Earthdata support can maintain each project's members, status, documentation, and artifact checklist. Furthermore, this solution provides a gateway for project communities to become familiar with NASA clients, as well as educating the project's NASA DAAC Scientists for NASA client distribution.

  19. Volume Resistivity Measurement of Insulating Material in Space Environment Simulated Condition

    NASA Astrophysics Data System (ADS)

    Watanabe, Rikio; Miyake, Hiroaki; Tanaka, Yasuhiro; Nitta, Kumi

    Volume resistivities of polyimide film under simulated space environment are measured with “charge storage decay method.” The test material was irradiated by electron beam in a vacuum chamber to simulate space environment. Volume resistivity is calculated from the surface potential decay time constant after stopping electron irradiation. This is called “charge storage decay method” and is shown to be the preferred method to determine resistivities of highly insulating materials. As a result of experiments, we have found that volume resistivity of polyimide film is in order of 1016 Ωm, which is one order higher than the result from the conventional resistivity measurement method prescribed in JIS or ASTM. Higher resistivity requires much longer field relaxation time after injection of electron to dissipate through the material. Thus, charging analysis of spacecraft needs to consider this higher resistivity. The effect of injection energy of electron is also examined and it is found that the higher the energy is, the faster the charge decay become.

  20. An approach to prior austenite reconstruction

    SciTech Connect

    Abbasi, Majid; Nelson, Tracy W.; Sorensen, Carl D.; Wei Lingyun

    2012-04-15

    One area of interest in Friction Stir Welding (FSW) of steels is to understand microstructural evolution during the process. Most of the deformation occurs in the austenite temperature range. Quantitative microstructural measurements of prior austenite microstructure are needed in order to understand evolution of the microstructure. Considering the fact that room temperature microstructure in ferritic steels contains very little to no retained austenite, prior austenite microstructure needs to be recovered from the room temperature ferrite. In this paper, an approach based on Electron Backscattered Diffraction (EBSD) is introduced to detect Bain zones. Bain zone detection is used to reconstruct prior austenite grain structure. Additionally, a separate approach based on phase transformation orientation relationships is introduced in order to recover prior austenite orientation. - Highlights: Black-Right-Pointing-Pointer This approach provides a tool to reconstruct large-scale austenite microstructures. Black-Right-Pointing-Pointer It recovers prior austenite orientation without relying on retained austenite. Black-Right-Pointing-Pointer It utilizes EBSD data from the room temperature microstructure. Black-Right-Pointing-Pointer Higher number of active variants leads to more accurate reconstructions. Black-Right-Pointing-Pointer At least two variants are needed in order to recover prior austenite orientation.

  1. Space Environment Measurements for Icy Surfaces in the Solar System and Beyond

    NASA Astrophysics Data System (ADS)

    Cooper, J. F.

    2002-12-01

    There are dozens of icy satellites orbiting the giant planets and trillions of icy comets populating the Kuiper Belt and Oort Cloud. Such objects are likely to be common throughout other planetary systems, particularly those now known to have giant plants. Interactions of the local space environment with these bodies must be taken in account for proper interpretation of photometric and spectroscopic measurements related to surface composition. Most of these bodies either are known to have, or likely have, tenuous atmospheres of volatile gases produced by internal outgassing and surface sublimation, sputtering from charged particle and UV irradiation, and diffuse dust clouds produced from meteoritic impacts. Whether or not Pluto counts as a small icy planet or a big comet, its thin and variable atmosphere also allows direct surface exposure to the space environment. Even glacial ices on the surface of (e.g., Snowball) Earth may have been exposed to much of the interplanetary solar UV flux at early times when an effective ozone shield was absent, and the Mars atmosphere is thin enough today for direct irradiation of polar cap ices by high energy cosmic ray and solar flare ions. Planetary magnetic fields reduce exposure to interplanetary charged particles but add irradiation by magnetospheric plasma and energetic particles. At Europa the intense surface irradiation from the Jovian magnetosphere might play a role via radiolytic chemistry in possible evolution of life within the putative sub-surface ocean. Although an armada of spacecraft have been measuring for many years the parameters of the solar UV, plasma, energetic particle, and dust environments of rocky bodies, large and small, in the inner solar system near Earth's orbit around the Sun, only six spacecraft with varying capabilities (Pioneer 10/11, Voyager 1/2, Galileo Orbiter, Cassini Orbiter) have yet ventured into the domain of the icy bodies near and beyond the orbit of Jupiter. The first five have

  2. Hydroxyl radical measurements and oxidation capacity in a boreal forest environment

    NASA Astrophysics Data System (ADS)

    Hens, K.; Tatum Ernest, C.; Novelli, A.; Paasonen, P.; Sipilä, M.; Petäjä, T.; Nölscher, A.; Taraborrelli, D.; Keronen, P.; Trawny, K.; Kubistin, D.; Oswald, R.; Axinte, R.; Hosaynali Beygi, Z.; Auld, J.; Klüpfel, T.; Mesarchaki, E.; Song, W.; Valverde Canossa, J.; González Orozco, D.; Königstedt, R.; Bohn, B.; Rudolf, M.; Fischer, H.; Williams, J.; Crowley, J.; Martinez, M.; Harder, H. D.; Lelieveld, J.

    2012-12-01

    Forests cover about one third of the earth's total land surface and are known to be an important global source of biogenic volatile organic compounds (BVOCs) that are partly very reactive towards OH. Different types of forests are known to emit various characteristic BVOCs significantly influencing atmospheric oxidation chemistry. Measurements of OH and HO2 radicals in forest environments, however, reveal a serious lack of understanding of the underlying processes. The HUMPPA-COPEC intensive field campaign took place in summer 2010 at the SMEAR II station, located in Hyytiälä, Southern Finland, as collaboration between the Max Planck Institute for Chemistry and the University of Helsinki. The main goal of the campaign was to investigate the summertime emissions and photochemistry in a boreal forest. Comprehensive measurements including observations of many VOCs, HOx, and total OH reactivity were conducted to increase our understanding of atmospheric self-cleaning processes based on detailed analysis of production and loss mechanisms of the hydroxyl radical. Also the HOx budget in a coniferous forest was examined by using direct calculations from measured species as well as an observationally constrained chemical box model in steady state. For HUMPPA-COPEC chemical reaction schemes considering isoprene as the predominant primary BVOC lead to an over prediction of the measured OH concentration by a factor of up to 4. However, only a minor fraction of the measured total OH reactivity can be explained by measured isoprene. A preliminary terpene mechanism, taking the most abundant terpenes measured during HUMPPA-COPEC-2010 and their oxidation products into account, improves the agreement between simulated and measured OH, but is not sufficient to explain the missing OH reactivity in all cases. HO2 is described reasonably well by the model for conditions where the modeled and measured total OH reactivity agree. For lower than measured reactivity, the HO2 mixing ratios

  3. Optical Mass Gauging System for Measuring Liquid Levels in a Reduced Gravity Environment

    NASA Technical Reports Server (NTRS)

    Sullenberger, Ryan M.; Munoz, Wesley M.; Lyon, Matt P.; Vogel, Kenny; Yalin, Azer P.; Korman, Valentin; Polzin, Kurt A.

    2010-01-01

    A compact and rugged fiber-coupled liquid volume sensor designed for flight on a sounding rocket platform is presented. The sensor consists of a Mach-Zehnder interferometer capable of measuring the amount of liquid contained in a tank under any gravitational conditions, including a microgravity environment, by detecting small changes in the index of refraction of the gas contained within a sensing region. By monitoring changes in the interference fringe pattern as the system undergoes a small compression provided by a piston, the ullage volume of a tank can be directly measured allowing for a determination of the liquid volume. To demonstrate the technique, data are acquired using two tanks containing different volumes of liquid, which are representative of the levels of liquid in a tank at different time periods during a mission. The two tanks are independently exposed to the measurement apparatus, allowing for a determination of the liquid level in each. In a controlled, laboratory test of the unit, the system demonstrated a capability of measuring a liquid level in an individual tank of 10.53 mL with a 2% error. The overall random uncertainty for the flight system is higher than that one test, at +/- 1.5 mL.

  4. Establishing aeolian particulate 'fingerprints' in an airport environment using magnetic measurements and SEM/EDAX

    NASA Astrophysics Data System (ADS)

    Jones, Sue; Hoon, Stephen R.; Richardson, Nigel; Bennett, Michael

    2016-04-01

    The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of particulate matter (PM) from aviation activity on health and the environment. PM within the airport environment, in particular, may be derived from a wide range of potential sources including aircraft; vehicles; ground support equipment and buildings. In order to investigate and remediate potential problem sources, it is important to be able to identify characteristic particulate 'fingerprints' which would allow source attribution, particularly respirable particulates. To date the identification of such 'fingerprints' has remained elusive but remains a key research priority for the aviation industry (Webb et al, 2008). In previous PM studies, environmental magnetism has been used as a successful technique for discriminating between different emission types and particulate sources in both urban and industrial environments (e.g. Hunt et al 1984; Lecoanet et al 2003, Jones et al 2015). Environmental magnetism is a non-destructive and relatively rapid technique involving the use of non-directional, rock magnetic measurements to characterise the mineral magnetic properties of natural and anthropogenic materials. In other studies scanning electron microscopy (SEM) has also been used as an effective characterisation technique for the investigation of grain size and morphology of PM derived from vehicle emissions (e.g. Bucko et al 2010) and fossil fuel combustion sources (Kim et al 2009). In this study, environmental magnetic measurements and SEM/EDAX have been used to characterise dusts from specific aircraft sources including engines, brakes and tyres. Furthermore, these methods have also been applied to runway (both hard and grass covered surfaces), taxiway and apron dusts collected during extensive environmental sampling at Manchester International Airport, UK in order to

  5. The Martian surface radiation environment - a comparison of models and MSL/RAD measurements

    NASA Astrophysics Data System (ADS)

    Matthiä, Daniel; Ehresmann, Bent; Lohf, Henning; Köhler, Jan; Zeitlin, Cary; Appel, Jan; Sato, Tatsuhiko; Slaba, Tony; Martin, Cesar; Berger, Thomas; Boehm, Eckart; Boettcher, Stephan; Brinza, David E.; Burmeister, Soenke; Guo, Jingnan; Hassler, Donald M.; Posner, Arik; Rafkin, Scot C. R.; Reitz, Günther; Wilson, John W.; Wimmer-Schweingruber, Robert F.

    2016-03-01

    Context: The Radiation Assessment Detector (RAD) on the Mars Science Laboratory (MSL) has been measuring the radiation environment on the surface of Mars since August 6th 2012. MSL-RAD is the first instrument to provide detailed information about charged and neutral particle spectra and dose rates on the Martian surface, and one of the primary objectives of the RAD investigation is to help improve and validate current radiation transport models. Aims: Applying different numerical transport models with boundary conditions derived from the MSL-RAD environment the goal of this work was to both provide predictions for the particle spectra and the radiation exposure on the Martian surface complementing the RAD sensitive range and, at the same time, validate the results with the experimental data, where applicable. Such validated models can be used to predict dose rates for future manned missions as well as for performing shield optimization studies. Methods: Several particle transport models (GEANT4, PHITS, HZETRN/OLTARIS) were used to predict the particle flux and the corresponding radiation environment caused by galactic cosmic radiation on Mars. From the calculated particle spectra the dose rates on the surface are estimated. Results: Calculations of particle spectra and dose rates induced by galactic cosmic radiation on the Martian surface are presented. Although good agreement is found in many cases for the different transport codes, GEANT4, PHITS, and HZETRN/OLTARIS, some models still show large, sometimes order of magnitude discrepancies in certain particle spectra. We have found that RAD data is helping to make better choices of input parameters and physical models. Elements of these validated models can be applied to more detailed studies on how the radiation environment is influenced by solar modulation, Martian atmosphere and soil, and changes due to the Martian seasonal pressure cycle. By extending the range of the calculated particle spectra with respect to

  6. The Importance of Prior Knowledge.

    ERIC Educational Resources Information Center

    Cleary, Linda Miller

    1989-01-01

    Recounts a college English teacher's experience of reading and rereading Noam Chomsky, building up a greater store of prior knowledge. Argues that Frank Smith provides a theory for the importance of prior knowledge and Chomsky's work provided a personal example with which to interpret and integrate that theory. (RS)

  7. Menarche: Prior Knowledge and Experience.

    ERIC Educational Resources Information Center

    Skandhan, K. P.; And Others

    1988-01-01

    Recorded menstruation information among 305 young women in India, assessing the differences between those who did and did not have knowledge of menstruation prior to menarche. Those with prior knowledge considered menarche to be a normal physiological function and had a higher rate of regularity, lower rate of dysmenorrhea, and earlier onset of…

  8. Measurement Error in Multilevel Models of School and Classroom Environments: Implications for Reliability, Precision, and Prediction. CRESST Report 828

    ERIC Educational Resources Information Center

    Schweig, Jonathan

    2013-01-01

    Measuring school and classroom environments has become central in a nation-wide effort to develop comprehensive programs that measure teacher quality and teacher effectiveness. Formulating successful programs necessitates accurate and reliable methods for measuring these environmental variables. This paper uses a generalizability theory framework…

  9. In-Situ Acoustic Measurements of Temperature Profile in Extreme Environments

    SciTech Connect

    Skliar, Mikhail

    2015-03-31

    A gasifier’s temperature is the primary characteristic that must be monitored to ensure its performance and the longevity of its refractory. One of the key technological challenges impacting the reliability and economics of coal and biomass gasification is the lack of temperature sensors that are capable of providing accurate, reliable, and long-life performance in an extreme gasification environment. This research has proposed, demonstrated, and validated a novel approach that uses a noninvasive ultrasound method that provides real-time temperature distribution monitoring across the refractory, especially the hot face temperature of the refractory. The essential idea of the ultrasound measurements of segmental temperature distribution is to use an ultrasound propagation waveguide across a refractory that has been engineered to contain multiple internal partial reflectors at known locations. When an ultrasound excitation pulse is introduced on the cold side of the refractory, it will be partially reflected from each scatterer in the US propagation path in the refractory wall and returned to the receiver as a train of partial echoes. The temperature in the corresponding segment can be determined based on recorded ultrasonic waveform and experimentally defined relationship between the speed of sound and temperature. The ultrasound measurement method offers a powerful solution to provide continuous real time temperature monitoring for the occasions that conventional thermal, optical and other sensors are infeasible, such as the impossibility of insertion of temperature sensor, harsh environment, unavailable optical path, and more. Our developed ultrasound system consists of an ultrasound engineered waveguide, ultrasound transducer/receiver, and data acquisition, logging, interpretation, and online display system, which is simple to install on the existing units with minimal modification on the gasifier or use with new units. This system has been successfully tested

  10. The Construction and Validation of a New Scale for Measuring Features of Constructivist Learning Environments in Higher Education

    ERIC Educational Resources Information Center

    Alt, Dorit

    2014-01-01

    This study was aimed at mapping features of constructivist activities in higher education settings, constructing and validating a new scale for measuring their presence in lecture face-to-face based environments (LBE), seminars (SM), and distance learning environments (DLE). A mix-method approach was implemented in three phases. The first phase…

  11. Cooperative Mobile Sensing Systems for In Situ Measurements in Hazardous Environments

    NASA Astrophysics Data System (ADS)

    Argrow, B.

    2005-12-01

    Sondes are typically deployed from manned aircraft or taken to altitude by a balloon before they are dropped. There are obvious safety and physical limitations that dictate where and how sondes are deployed. These limitations have severely constrained sonde deployment into highly dynamic and dangerous environments. Additionally, conventional parachute dropsondes provide no means for active control. The "smartsonde" idea is to integrate miniature sonde packages into micro air vehicles (MAVs). These MAVs will be ferried into the hard to reach and hazardous environments to provide in situ measurements in regions that have been heretofore out of reach. Once deployed, the MAV will provide some means of control of the sonde, to enable it to remain aloft and to provide some measure of directional control. Preliminary smartsonde communications experiments have been completed. These experiments focused on characterizing the capabilities of the 802.11.4 wireless protocol. Range measurements with 60-mW, 2.4-GHz radios showed 100% throughput rate over 2.7 km during air to ground tests. The experiments also demonstrated the integration of an in-house distributed computing system that provides the interface between the sensors, UAV flight computers, and the telemetry system. The University of Colorado's Research and Engineering Center for Unmanned Vehicles (RECUV) is developing an engineering system that integrates small mobile sensor attributes into flexible mobile sensor infrastructures to be deployed for in situ sensing in hazardous environments. There are three focus applications: 1) Wildfire, to address sensing, communications, situational awareness, and safety needs to support fire-fighting operations and to increase capabilities for dynamic data acquisition for modeling and prediction; 2) Polar, where heterogeneous mixes of platforms and sensors will provide in-situ data acquisition from beneath the ocean surface into the troposphere; 3) Storm, to address the challenges

  12. Shallow water radio-magnetotelluric (RMT) measurements in urban environment: A case study from Stockholm city

    NASA Astrophysics Data System (ADS)

    Mehta, Suman; Bastani, Mehrdad; Malehmir, Alireza; Wang, Shunguo; Pedersen, Laust

    2014-05-01

    The Radio-MagnetoTelluric (RMT) method uses the electromagnetic signal from distant radio transmitters in the frequency range 15 to 250 kHz. RMT applications in near-surface studies have already been well established. Two components of electric field and three components of magnetic field are measured. These measured components are related to each other via transfer functions which contain detailed information about the variation of electrical resistivity of the subsurface. The present study is carried out in the frame of TRUST (TRansparent Underground STructure) project supported by several research and public organizations as well as industry. The study area is located close to central Stockholm in Sweden where the Swedish traffic authority has planned to construct a 21-km long motorway to bypass the city. In order to reduce the impact on natural and cultural environments, 18 km of the motorway will be located in tunnels. The main objective of this study is thus to identify potential fracture zones and faults as well as the general geological settings. The proposed path of the tunnel partly passes under the Lake Mälaren at a depth of about 60 m. Thus a challenge was posed on the applicability of RMT method in shallow water environments. Successful applications of RMT measurements using the Uppsala University's EnviroMT system on land encouraged us to modify the system to acquire data over lake water especially in urban areas. Pioneered by the Geological Survey of Sweden (SGU), RMT data were collected over the Lake Mälaren in spring 2012. The prototype acquisition system did not only turn out to be appropriate for such a challenging environment, but it was also much more efficient as compared with land surveys. Fifty two lines including 1160 stations with an average spacing of 15 m were covered in three days. Cultural noise associated with the city-related environment had to be identified and filtered out before inversion could be carried out. Reliable estimates

  13. Measuring microbial metabolism in atypical environments: Bentonite in used nuclear fuel storage.

    PubMed

    Stone, Wendy; Kroukamp, Otini; Moes, Ana; McKelvie, Jennifer; Korber, Darren R; Wolfaardt, Gideon M

    2016-01-01

    Genomics enjoys overwhelming popularity in the study of microbial ecology. However, extreme or atypical environments often limit the use of such well-established tools and consequently demand a novel approach. The bentonite clay matrix proposed for use in Deep Geological Repositories for the long-term storage of used nuclear fuel is one such challenging microbial habitat. Simple, accessible tools were developed for the study of microbial ecology and metabolic processes that occur within this habitat, since the understanding of the microbiota-niche interaction is fundamental to describing microbial impacts on engineered systems such as compacted bentonite barriers. Even when genomic tools are useful for the study of community composition, techniques to describe such microbial impacts and niche interactions should complement these. Tools optimised for assessing localised microbial activity within bentonite included: (a) the qualitative use of the resazurin-resorufin indicator system for redox localisation, (b) the use of a CaCl2 buffer for the localisation of pH, and (c) fluorometry for the localisation of precipitated sulphide. The use of the Carbon Dioxide Evolution Monitoring System was also validated for measuring microbial activity in desiccated and saturated bentonite. Finally, the buffering of highly-basic bentonite at neutral pH improved the success of isolation of microbial populations, but not DNA, from the bentonite matrix. Thus, accessible techniques were optimised for exploring microbial metabolism in the atypical environments of clay matrices and desiccated conditions. These tools have application to the applied field of used nuclear fuel management, as well as for examining the fundamental biogeochemical cycles active in sedimentary and deep geological environments. PMID:26578245

  14. Psychometric analysis of the ambulatory care learning education environment measure (ACLEEM) in Iran

    PubMed Central

    Naghizadeh Moogari, Zahra; Koohpayehzadeh, Jalil; Roff, Susanne; Montazeri, Ali; Soltani Arabshahi, Seyyed Kamran; Bigdeli, Shoaleh; Moosavi, Maryam; Azaminejad, Faranak; Tavousi, Mahmoud

    2015-01-01

    Background: Examining educational environment (academic and clinical) by means of a valid, reliable and comprehensive questionnaire is a major key in achieving a highly qualified student – oriented curricula. The Persian translation of Ambulatory Care Learning Education Environment Measure-ACLEEM questionnaire has been developed to support this goal, and its psychometrics has been explored in this administration in teaching hospitals affiliated to Tehran University of Medical Sciences. Methods: This descriptive – analytical study involved medical residents in four major clinics. In this study, the ACLEEM Questionnaire was conducted after translating and retranslating the questionnaire and examine the face and content validity, construct validity, test retest reliability and internal consistency coefficient. Results: In this study, 157 out of 192 residents completed the questionnaire (response rate 82%). The mean age of the residents was 31.81 years .The final mean of the questionnaire was calculated as 110.91 out of 200 (with 95% confidence interval). Test – retest stability of the questionnaire was between 0.322 and 0.968. The face validity of the questionnaire was confirmed. The content validity ratio was 0.64; and content validity Index was 0.78. In Exploratory factor analysis, eight factors were confirmatory that changed the orientation of some questions. The Cronbach's alpha coefficient of the whole questionnaire was 0.936. Conclusion: According to the data, the Persian version of the ACLEEM questionnaire has sufficient psychometric reliability and validity to be used for conducting research, teaching and practicing the educational learning environment in ambulatory care in Iran. PMID:26913262

  15. In situ Measurements of Absorbing Aerosols from Urban Sources, in Maritime Environments and during Biomass Combustion

    NASA Astrophysics Data System (ADS)

    Mazzoleni, C.; Manvendra, D.; Chylek, P.; Arnott, P.

    2006-12-01

    Absorbing aerosols have important but still ill quantified effects on climate, visibility, cloud processes, and air quality. The compilation of aerosol scattering and absorption databases from reliable measurements is essential to reduce uncertainties in these inter-linked research areas. The atmospheric radiative balance for example, is modeled using the aerosol single scattering albedo (ratio of scattering to scattering plus absorption, SSA) as a fundamental input parameter in climate models. Sulfate aerosols with SSA values close to 1 scatter solar radiation resulting in a negative radiative forcing. However aerosol SSA values less than 1 are common when combustion processes are contributing to the aerosol sources. Absorbing aerosols directly heat the atmosphere and reduce the solar radiation at the surface. Currently, the net global anthropogenic aerosol direct radiative forcing is estimated to be around -0.5W m-2 with uncertainty of about 80% largely due to lack of understanding of SSA of sulfate-organic-soot aerosols. We present a rapidly expanding data set of direct in situ aerosol absorption and scattering measurements performed since June 2005 by photoacoustic instrument (at 781 and 870 nm), with integrated a total scattering sensor, during numerous field campaigns. Data have been collected over a wide range of aerosol sources, local environments and anthropogenic activities. Airborne measurements were performed in marine stratus off shore of the California coast and in cumulus clouds and clear air in the Houston, TX area; ground-based measurements have been performed in many locations in Mexico City; while laboratory measurements have been collected during a controlled combustion experiment of many different biomass fuels. The large dynamic range of aerosol types and conditions from these different field campaigns will be integrated to help quantify the SSA values, their variability, and their implications on the radiative forcing of climate.

  16. Experimental Investigation of Liquid-Level Measuring Accuracy in a Low Pressure Environment

    SciTech Connect

    Adamson, D.J.

    1996-10-01

    Dip Tubes which are used for determining liquid level in many processes at SRS will be used to measure the liquid level of the Am/Cm solution in the Feed Tank at the MPPF. The Feed Tank operates under a vacuum, therefore the Dip Tubes will operate under a vacuum. Uncertainty in how accurate the Dip Tubes would perform in a vacuum environment led to testing. The Am/Cm Melter Liquid-Feed Tank measurement test was mocked-up per Figure 1. The Feed Tank was designed to simulate actual conditions in which the Dip Tubes would measure the differential pressure. The Feed Tank was made of Stainless Steel with a Lexan window to view inside the tank during testing. The Feed Tank was built per Drawing SRT-ETF-DD-96008, Revision A. The accuracy of the Dip Tubes was checked first by filling the Feed Tank at a flow rate of 3.5 L/min and venting it to the atmosphere. Figure 2 shows that the Dip Tubes were responsive and accurate when compared to the data from the measuring scale on the view window. Then tests were conducted with 23y Hg vacuum inside the tank and water flow rates of 3.9 L/min, 1.8 L/min, and 0.7 L/min being fed to the tank. The data from each test are depicted in Figure 3, Figure 4, and Figure 5, respectively. The Dip Tubes responded accurately for the three test with a maximum error range of +0.31y to -0.19y when compared to the measuring scale located next to the view window on the Feed Tank.

  17. Measurement and Modeling of Hydrogen Environment-Assisted Cracking in Monel K-500

    NASA Astrophysics Data System (ADS)

    Gangloff, Richard P.; Ha, Hung M.; Burns, James T.; Scully, John R.

    2014-08-01

    Hydrogen environment-assisted cracking (HEAC) of Monel K-500 is quantified using slow-rising stress intensity loading with electrical potential monitoring of small crack propagation and elastoplastic J-integral analysis. For this loading, with concurrent crack tip plastic strain and H accumulation, aged Monel K-500 is susceptible to intergranular HEAC in NaCl solution when cathodically polarized at -800 mVSCE ( E A, vs saturated calomel) and lower. Intergranular cracking is eliminated by reduced cathodic polarization more positive than -750 mVSCE. Crack tip diffusible H concentration rises, from near 0 wppm at E A of -765 mVSCE, with increasing cathodic polarization. This behavior is quantified by thermal desorption spectroscopy and barnacle cell measurements of hydrogen solubility vs overpotential for planar electrodes, plus measured-local crevice potential, and pH scaled to the crack tip. Using crack tip H concentration, excellent agreement is demonstrated between measurements and decohesion-based model predictions of the E A dependencies of threshold stress intensity and Stage II growth rate. A critical level of cathodic polarization must be exceeded for HEAC to occur in aged Monel K-500. The damaging-cathodic potential regime likely shifts more negative for quasi-static loading or increasing metallurgical resistance to HEAC.

  18. HOx Radical Chemistry in an Indiana Forest Environment: Measurement and Model Comparison

    NASA Astrophysics Data System (ADS)

    Lew, M.; Bottorff, B.; Sigler, P. S. R.; Stevens, P. S.; Sklaveniti, S.; Leonardis, T.; Locoge, N.; Dusanter, S.; Kundu, S.; Deming, B.; Wood, E. C. D.; Gentner, D. R.

    2015-12-01

    Reactions of the hydroxyl (OH) and peroxy radicals (HO2 and RO2) play a central role in the chemistry of the atmosphere. In addition to controlling the lifetimes of many trace gases important to issues of global climate change, OH radical reactions initiate the oxidation of volatile organic compounds (VOCs) which can lead to the production of ozone and secondary organic aerosols in the atmosphere. Previous measurements of these radicals in forest environments characterized by high mixing ratios of isoprene and low mixing ratios of NOx have shown serious discrepancies with modeled concentrations. These results bring into question our understanding of the atmospheric chemistry of isoprene and other biogenic VOCs under low NOx conditions. In the summer of 2015, HOx radicals were measured using Laser-Induced Fluorescence Fluorescence Assay by Gas Expansion (LIF-FAGE) technique as part of the Indiana Radical, Reactivity and Ozone Production Intercomparison (IRRONIC). This campaign took place in a forested area at the Indiana Research and Teaching Preserve (IURTP) near the Bloomington campus characterized by high mixing ratios of isoprene and low mixing ratios of NOx. Supporting measurements of photolysis rates, volatile organic compounds, nitrogen oxides, and other species were used to constrain a zero-dimensional box model based on the Regional Atmospheric Chemistry Mechanism (RACM2) and the Master Chemical Mechanism (MCM).

  19. A 100g Mass Comparator with an Improved Readability and Measuring Environment

    NASA Astrophysics Data System (ADS)

    Ueki, Masaaki; Sun, Jian-Xin; Ueda, Kazunaga

    In order to achieve higher accuracy of the mass standard in the mass range equal to or less than 100g, it is necessary for a mass comparator in the range to have a relative sensitivity of the order of 1×10-9. For this purpose, a 111g capacity fully-automatic mass comparator has been renovated so that its readability is improved from 1 to 0.1µg. The mass comparator is also installed in an air-tight chamber originally developed by the NMIJ, so that it can be kept in stable environment, especially in the air of constant density. With these renovations, standard deviation of the mass comparisons is reduced and uncertainty of the air buoyancy corrections is lessened. This paper reports the features of the improved 100g mass comparator, the empirical method to evaluate its performance and the obtained results. As a result, the standard deviations of the mass difference measurements have been greatly improved to 0.22µg in the average with the chamber closed, compared with 0.97µg with the one open. The linearity of the comparator has been also verified by the mass difference measurements of weights at the six masses of 10, 20, 30, 50, 70 and 100g, and it confirms that the non-linearity errors of the comparator are within 0.28µg, showing good measuring performance.

  20. Measuring motivation and volition of nursing students in nontraditional learning environments.

    PubMed

    Nagelsmith, Laurie; Bryer, Jason; Yan, Zheng

    2012-01-01

    The purpose of this study was to identify the best fitting model to represent interrelationships between motivation, volition, and academic success for adult nursing students learning in nontraditional environments. Participants (N=297) completed a survey that incorporated two measures: the Motivated Strategies for Learning Questionnaire (MSLQ) and the academic volitional strategies inventory (AVSI) as well as demographic information. Exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM) were used for data analysis. In phase 1, EFA resulted in factors that generally aligned with previous theoretical factors as defined by the psychometrics used. In Phase 2 of the analysis, CFA validated the use of predefined factor structures. In Phase 3, SEM analysis revealed that motivation has a larger effect on grade point average (GPA; beta = .28, p < .01) than volition (beta = .15, p < .05). The covariance between motivation and volition (r = .42, p < .01) was also found to be significant. These results suggest that there is a significant relationship among motivation, volition, and academic success for adult learners studying in nontraditional learning environments. These findings are consistent with and elaborate the relationship between motivation and volition with a population and setting underrepresented in the research. PMID:22988781

  1. Fitting Procedures for Novel Gene-by-Measured Environment Interaction Models in Behavior Genetic Designs

    PubMed Central

    Zheng, Hao; Rathouz, Paul J.

    2015-01-01

    For quantitative behavior genetic (e.g., twin) studies, Purcell proposed a novel model for testing gene-by-measured environment (GxM) interactions while accounting for gene-by-environment correlation. Rathouz et al. expanded this model into a broader class of non-linear biometric models for quantifying and testing such interactions. In this work, we propose a novel factorization of the likelihood for this class of models, and adopt numerical integration techniques to achieve model estimation, especially for those without close-form likelihood. The validity of our procedures is established through numerical simulation studies. The new procedures are illustrated in a twin study analysis of the moderating effect of birth weight on the genetic influences on childhood anxiety. A second example is given in an online appendix. Both the exant GxM models and the new non-linear models critically assume normality of all structural components, which implies continuous, but not normal, manifest response variables. PMID:25732055

  2. Fluorescence measurements for evaluating the application of multivariate analysis techniques to optically thick environments.

    SciTech Connect

    Reichardt, Thomas A.; Timlin, Jerilyn Ann; Jones, Howland D. T.; Sickafoose, Shane M.; Schmitt, Randal L.

    2010-09-01

    Laser-induced fluorescence measurements of cuvette-contained laser dye mixtures are made for evaluation of multivariate analysis techniques to optically thick environments. Nine mixtures of Coumarin 500 and Rhodamine 610 are analyzed, as well as the pure dyes. For each sample, the cuvette is positioned on a two-axis translation stage to allow the interrogation at different spatial locations, allowing the examination of both primary (absorption of the laser light) and secondary (absorption of the fluorescence) inner filter effects. In addition to these expected inner filter effects, we find evidence that a portion of the absorbed fluorescence is re-emitted. A total of 688 spectra are acquired for the evaluation of multivariate analysis approaches to account for nonlinear effects.

  3. High Speed Railway Environment Safety Evaluation Based on Measurement Attribute Recognition Model

    PubMed Central

    Hu, Qizhou; Zhang, Bing

    2014-01-01

    In order to rationally evaluate the high speed railway operation safety level, the environmental safety evaluation index system of high speed railway should be well established by means of analyzing the impact mechanism of severe weather such as raining, thundering, lightning, earthquake, winding, and snowing. In addition to that, the attribute recognition will be identified to determine the similarity between samples and their corresponding attribute classes on the multidimensional space, which is on the basis of the Mahalanobis distance measurement function in terms of Mahalanobis distance with the characteristics of noncorrelation and nondimensionless influence. On top of the assumption, the high speed railway of China environment safety situation will be well elaborated by the suggested methods. The results from the detailed analysis show that the evaluation is basically matched up with the actual situation and could lay a scientific foundation for the high speed railway operation safety. PMID:25435866

  4. USB environment measurements based on full-scale static engine ground tests

    NASA Technical Reports Server (NTRS)

    Sussman, M. B.; Harkonen, D. L.; Reed, J. B.

    1976-01-01

    Flow turning parameters, static pressures, surface temperatures, surface fluctuating pressures and acceleration levels were measured in the environment of a full-scale upper surface blowing (USB) propulsive lift test configuration. The test components included a flightworthy CF6-50D engine, nacelle, and USB flap assembly utilized in conjunction with ground verification testing of the USAF YC-14 Advanced Medium STOL Transport propulsion system. Results, based on a preliminary analysis of the data, generally show reasonable agreement with predicted levels based on model data. However, additional detailed analysis is required to confirm the preliminary evaluation, to help delineate certain discrepancies with model data, and to establish a basis for future flight test comparisons.

  5. Investigating factor structure of an instrument to measure social work students' preparedness for managed care environments.

    PubMed

    Kane, Michael N; Houston-Vega, Mary Kay; Tan, Philip P; Hawkins, Wesley E

    2002-01-01

    This study investigated the factor structure of an instrument to measure social work students' perceptions of preparedness to enter managed care environments. Exploratory statistical procedures to reduce data through principle component analysis identified nine factors with eigenvalues greater than 1.0. These factors include: perceived understanding of agency financial agendas, managing personal risk and liability, perceived understanding of agency documentation requirements, awareness of ethical and value conflicts in documentation, classroom preparation for documentation, understanding the fit between client advocacy and managed care agendas, worrying about law suits in employment settings, perceived understanding of managed care gatekeeping and service authorization, and perceptions of field preparation for documentation. Recommendations are made for utilizing this brief self-report instrument in training students for managed care settings. PMID:12425449

  6. High speed railway environment safety evaluation based on measurement attribute recognition model.

    PubMed

    Hu, Qizhou; Gao, Ningbo; Zhang, Bing

    2014-01-01

    In order to rationally evaluate the high speed railway operation safety level, the environmental safety evaluation index system of high speed railway should be well established by means of analyzing the impact mechanism of severe weather such as raining, thundering, lightning, earthquake, winding, and snowing. In addition to that, the attribute recognition will be identified to determine the similarity between samples and their corresponding attribute classes on the multidimensional space, which is on the basis of the Mahalanobis distance measurement function in terms of Mahalanobis distance with the characteristics of noncorrelation and nondimensionless influence. On top of the assumption, the high speed railway of China environment safety situation will be well elaborated by the suggested methods. The results from the detailed analysis show that the evaluation is basically matched up with the actual situation and could lay a scientific foundation for the high speed railway operation safety. PMID:25435866

  7. Light Emitting Diodes and Astronomical Environments: Results from in situ Field Measurements

    NASA Astrophysics Data System (ADS)

    Craine, Brian L.; Craine, Eric R.

    2015-05-01

    Light emitting diode (LED) light fixtures are rapidly becoming industry standards for outdoor lighting. They are promoted on the strength of long lifetimes (hence economic efficiencies), low power requirements, directability, active brightness controls, and energy efficiency. They also tend to produce spectral shifts that are undesirable in astronomical settings, but which can be moderated by filters. LED lighting for continuous roadway and parking lot lighting is particularly popular, and many communities are in the process of retrofitting Low Pressure Sodium (LPS) and other lights by tens of thousands of new LED fixtures at a time. What is the impact of this process on astronomical observatories and on dark skies upon which amateur astronomers rely? We bypass modeling and predictions to make actual measurements of these lights in the field. We report on original ground, airborne, and satellite observations of LED lights and discuss their light budgets, zenith angle functions, and impacts on observatory environs.

  8. Community food environment measures in the Alabama Black Belt: Implications for cancer risk reduction

    PubMed Central

    Gyawu, Rebecca; Quansah, Joseph E.; Fall, Souleymane; Gichuhi, Peter N.; Bovell-Benjamin, Adelia C.

    2015-01-01

    In-store measures were utilized to evaluate the availability of healthy food choices and nutrition/health promotion messages for cancer risk reduction in the selected Alabama Black Belt counties/cities. Sixty one retail food outlets (RFOs) were audited in 12 Alabama Black Belt cities. Store types included convenience stores (49.2%), restaurants (19.7%), fast food restaurants (16.4%), small supermarkets (8.2%), and large supermarket and farmers' markets (3.3 %), respectively. Although there were low numbers of farmers' markets/street stands and large supermarkets, these had significantly (p < 0.0001) higher health scores than the other store types. A few health promotion messages were highly visible or obscurely positioned in some RFOs. The Alabama Black Belt food environment had limited opportunities for healthy food choices. PMID:26844138

  9. Distributed optical fibre temperature measurements in a low dose rate radiation environment based on Rayleigh backscattering

    NASA Astrophysics Data System (ADS)

    Faustov, A.; Gussarov, A.; Wuilpart, M.; Fotiadi, A. A.; Liokumovich, L. B.; Kotov, O. I.; Zolotovskiy, I. O.; Tomashuk, A. L.; Deschoutheete, T.; Mégret, P.

    2012-04-01

    On-line monitoring of environmental conditions in nuclear facilities is becoming a more and more important problem. Standard electronic sensors are not the ideal solution due to radiation sensitivity and difficulties in installation of multiple sensors. In contrast, radiation-hard optical fibres can sustain very high radiation doses and also naturally offer multi-point or distributed monitoring of external perturbations. Multiple local electro-mechanical sensors can be replaced by just one measuring fibre. At present, there are over four hundred operational nuclear power plants (NPPs) in the world 1. Operating experience has shown that ineffective control of the ageing degradation of major NPP components can threaten plant safety and also plant life. Among those elements, cables are vital components of I&C systems in NPPs. To ensure their safe operation and predict remaining life, environmental monitoring is necessary. In particular, temperature and radiation dose are considered to be the two most important parameters. The aim of this paper is to assess experimentally the feasibility of optical fibre temperature measurements in a low doserate radiation environment, using a commercially available reflectometer based on Rayleigh backscattering. Four different fibres were installed in the Sub-Pile Room of the BR2 Material testing nuclear reactor in Mol, Belgium. This place is man-accessible during the reactor shut-down, allowing easy fibre installation. When the reactor operates, the dose-rates in the room are in a range 0.005-5 Gy/h with temperatures of 40-60 °C, depending on the location. Such a surrounding is not much different to some "hot" environments in NPPs, where I&C cables are located.

  10. X-ray based displacement and strain measurements for hostile environments

    NASA Technical Reports Server (NTRS)

    Canistraro, Howard A.; Jordan, Eric H.; Pease, Douglas M.

    1993-01-01

    A completely new method of non-contacting, hostile environment displacement and strain measurement based on the focus and scanning of x-rays, has been developed and demonstrated. The new technique has the ability to overcome many of the limitations associated with available methods. The system is based on the focus and scanning of low energy, hard x-rays such as those emanating from table top copper or molybdenum sources. The x-rays are focused into a narrow and intense line image which can be swept onto targets that fluoresce secondary x-ray radiation. By monitoring the secondary radiation intensity and comparing it with the focused x-ray image's position as it is swept over the target edge, the position of the target edge relative to the focused image can be determined. The present system has a resolution of 0.5 micron, which has been shown to be limited by bearing backlash (or 'yaw' error) in the linear translation table. Its use has been demonstrated in the presence of an open flame with a resultant target temperature in excess of 2000 degrees Fahrenheit (1000 degrees Celsius). Strain measurements have been conducted in a laboratory environment at both room temperature and at a specimen temperature of 1300 degrees Fahrenheit, with an accuracy of within 20 microstrain (primarily a function of the 0.5 micron resolution limit). The main advantage of the technique lies in the penetrating, non-refractive nature of x-rays, which are virtually immune to the presence of refracting gas layers, smoke, flame or intense thermal radiation.

  11. Time-resolved measurements of aerosol elemental concentrations in indoor working environments

    NASA Astrophysics Data System (ADS)

    Žitnik, M.; Kastelic, A.; Rupnik, Z.; Pelicon, P.; Vaupetič, P.; Bučar, K.; Novak, S.; Samardžija, Z.; Matsuyama, S.; Catella, G.; Ishii, K.

    2010-12-01

    We have measured the elemental concentrations in aerosols with a 2-h time resolution in two different types of working environment: a chemistry laboratory dealing with the processing of advanced nanoparticulate materials and a medium-sized machine workshop. Non-stop 10-day and 12-day samplings were performed at each location in order to determine the concentration trends during the non-working/working and weekday/weekend periods. Supplementary measurements of PM10 aerosols with a 2-day sample collection time were performed with a standard Gent PM10 sampler to compare the elemental concentrations with the time-averaged concentrations detected by the 2D step-sampler. The concentrations were determined a posteriori by analyzing the x-ray spectra of aerosol samples emitted after 3-MeV proton bombardment. The PM10 samples collected in the chemistry laboratory were additionally inspected by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) to determine the chemical compositions of the individual particles. In the workshop, a total PM10 mass sampling was performed simultaneously with a minute resolution to compare the signal with typical outdoor PM10 concentration levels. A factor analysis of the time-resolved dataset points to six and eight factors in the chemistry laboratory and the machine workshop, respectively. These factors describe most of the data variance, and their composition in terms of different elements can be related to specific indoor activities and conditions. We were able to demonstrate that the elemental concentration sampling with hourly resolution is an excellent tool for studying the indoor air pollution. While sampling the total PM10 mass concentration with a minute resolution may lack the potential to identify the emission sources in a "noisy" environment, the time averaging on a day time scale is too coarse to cope with the working dynamics, even if elemental sensitivity is an option.

  12. Worksite environment physical activity and healthy food choices: measurement of the worksite food and physical activity environment at four metropolitan bus garages

    PubMed Central

    Shimotsu, Scott T; French, Simone A; Gerlach, Anne F; Hannan, Peter J

    2007-01-01

    Background The present research describes a measure of the worksite environment for food, physical activity and weight management. The worksite environment measure (WEM instrument) was developed for the Route H Study, a worksite environmental intervention for weight gain prevention in four metro transit bus garages in Minneapolis-St. Paul. Methods Two trained raters visited each of the four bus garages and independently completed the WEM. Food, physical activity and weight management-related items were observed and recorded on a structured form. Inter-rater reliability was computed at the item level using a simple percentage agreement. Results The WEM showed high inter-rater reliability for the number and presence of food-related items. All garages had vending machines, microwaves and refrigerators. Assessment of the physical activity environment yielded similar reliability for the number and presence/absence of fitness items. Each garage had a fitness room (average of 4.3 items of fitness equipment). All garages had at least one stationary bike and treadmill. Three garages had at least one weighing scale available. There were no designated walking areas inside or outside. There were on average < 1 food stores or restaurants within sight of each garage. Few vending machine food and beverage items met criteria for healthful choices (15% of the vending machine foods; 26% of the vending machine beverages). The garage environment was perceived to be not supportive of healthy food choices, physical activity and weight management; 52% reported that it was hard to get fruits and vegetables in the garages, and 62% agreed that it was hard to be physically active in the garages. Conclusion The WEM is a reliable measure of the worksite nutrition, physical activity, and weight management environment that can be used to assess changes in the work environment. PMID:17498308

  13. The System of the Calibration for Visibility Measurement Instrument Under the Atmospheric Aerosol Simulation Environment

    NASA Astrophysics Data System (ADS)

    Shu, Zhifeng; Yang, ShaoChen; Xu, Wenjing

    2016-06-01

    divided by 3 is MOR. The aerosol concentration in chamber can be changed by adjusting aerosol generator that producing variety of visibility atmospherical environment. The experiment has been carried out and the measurement accuracy of atmospheric transmittance is 0.3‰ Corresponding to the accuracy of MOR 4.9% at the 2km visibility environment. So this system can be calibrated and validated the other visibility measuring devices.

  14. Measurement of Effective Canopy Temperature: The Missing Link to Modeling Transpiration in Controlled Environments

    NASA Technical Reports Server (NTRS)

    Monje, O. A.; McCormack, Ann; Bugbee, Bruce; Jones, Harry W., Jr. (Technical Monitor)

    1994-01-01

    The objectives were to apply energy balance principles to plant canopies, and to determine which parameters are essential for predicting plant canopy transpiration (E) in controlled environments. Transpiration was accurately measured in a gas-exchange system. Absorbed radiation (R(sub abs)) by the canopy was measured with a net radiometer and calculated from short and long-wave radiation components. Average canopy foliar temperature T(sub L) can be measured with an infrared radiometer, but since T(sub L) is seldom uniform, a weighed average measurement of T(sub L) must be made. The effective canopy temperature T(sub C) is that temperature that balances the energy flux between absorbed radiation and latent heat L(sub E) and sensible heat (H) fluxes. TC should exactly equal air temperature T(sub A) when L(sub E) equals R(sub abs). When unnecessary thermal radiation from the lighting system is removed by a water filter, the magnitude of L(sub E) from transpiration approaches Rabs and T(sub C) is close to T(sub A). Unlike field models, we included the energy used in photosynthesis and found that up to 10% of Rabs was used in photosynthesis. We calculated aerodynamic conductance for H from measurements of wind speed and canopy height using the wind profile equation. Canopy aerodynamic conductance ranged from.03 to.04 m/s for wind speeds from.6 to 1 m/s; thus a 0.1 C canopy to air temperature difference results in a sensible heat flux of about 4 W/sq m, which is only 1% of R(sub abs). We examined the ability of wide angle infrared transducers to accurately integrate T(sub L) from the top to the bottom of the canopy. We measured evaporation from the hydroponic media to be approximately 1 micro mol/sq m s or 10% of R(sub abs). This result indicates that separating evaporation from transpiration is more important than exact measurement of canopy temperature.

  15. Radiation Protection. Measurement of radioactivity in the environment - Air- radon 222. A proposed ISO standard.

    NASA Astrophysics Data System (ADS)

    Gillmore, G.; Woods, M.

    2009-04-01

    Radon isotopes (222, 220, 219) are radioactive gases produced by the disintegration of radium isotopes 226, 224 and 223, which are decay products of uranium238, thorium232 and uranium235 respectively. All are found in the earth's crust. Solid elements, also radioactive, are produced by radon disintegration. Radon is classed as a rare gas in the periodic table of elements, along with helium, argon, neon, krypton and xenon. When disintegrating, radon emits alpha particles and generates solid decay products, which are also radioactive (polonium, bismuth, lead etc.). The potential danger of radon lies in its solid decay products rather than the gas itself. Whether or not they are attached aerosols, radon decay products can be inhaled and deposited in the bronchopulmonary tree to varying depths according to their size. Radon today is considered to be the main source of human exposure to natural radiation. At the international level, radon accounts for 52% of global average exposure to natural radiation. Isotope 222 (48%) is far more significant than isotope 220 (4%), whilst isotope 219 is considered as negligible. Exposure to radon varies considerably from one region to another, depending on factors such as weather conditions, and underlying geology. Activity concentration can therefore vary by a factor of 10 or even a 100 from one period of time to the next and from one area to another. There are many ways of measuring the radon 222 activity concentration and the potential alpha energy concentration of its short-lived decay products. Measuring techniques fall into three categories: - spot measurement methods; continuous measurement; integrated measurement. The proposed ISO (International Organisation for Standardisation) document suggests guidelines for measuring radon222 activity concentration and the potential alpha energy concentration of its short-lived decay products in a free (environment) and confined (buildings) atmosphere. The target date for availability of

  16. Work function measurements of olivine: Implication to photoemission charging properties in planetary environments

    NASA Astrophysics Data System (ADS)

    Gan, Hong; Li, Xiongyao; Wei, Guangfei; Wang, Shijie

    2015-12-01

    For understanding the ubiquitous photoemission charging of solid surface in planetary environments, it is important to characterize the photoemission charging properties of silicate minerals such as the work function. In this study, we measured the work function of olivine mineral based on the measurements of contact potential difference by using an ultrahigh vacuum Kelvin probe force microscopy. Our results showed that work function on olivine mineral surface is mainly affected by surface morphology and crystal orientation and that the variation range of work function is 7.3-8.5 eV. It implicates that photoemission of the olivine mineral occurs under the X-ray and solar ultraviolet irradiation with wavelength of <171 nm. Consequently, it is possible to form electrostatic field of +(5-10) V on the sunlit planet, moon or asteroid surfaces due to dust photoemission charging, which even induces the migration of dust grains and the formation of dust-plasma atmosphere. Those are important problems worried to be solved for future lunar missions. Additionally, our work can help to instruct the dust mitigation technology and the electrostatic beneficiation in future space missions.

  17. Magnetoresistive sensors for angle, position, and electrical current measurement in demanding environments

    NASA Astrophysics Data System (ADS)

    Doms, Marco; Slatter, Rolf

    2014-06-01

    Nowadays, magnetoresistive (MR) sensors are used in a wide range of applications. In general, the MR-effect describes the change of the electrical resistance in an external magnetic field. MR sensors are not only used for measuring magnetic fields and rotational or linear motion, but also for non-contact switching applications and furthermore for highly dynamic current measurement. This is largely the result of increasingly complex demands on the sensors for e.g. high performance electrical drives. The sensors must not only be accurate and dynamic, but must also be robust under difficult operating conditions and exhibit very high reliability. Due to their physical working principle and their small size, MR sensors are especially suited to work in harsh environments like high or low temperature, radiation, pressure or mechanical shock. This paper describes the principle of operation, manufacturing process and benefits of MR sensors. This will be followed by a description of practical application examples from the automotive, oil and gas, renewable energy and space fields, where MR sensors are successfully applied in very small envelopes at very low /very high temperatures, under high pressure, high mechanical loading and under strong radiation.

  18. Measurement of dissolved organic matter fluorescense in aquatic environments: An interlaboratory comparison

    USGS Publications Warehouse

    Murphy, Kathleen R.; Butler, Kenna D.; Spencer, Robert G. M.; Stedmon, Colin A.; Boehme, Jennifer R.; Aiken, George R.

    2010-01-01

    The fluorescent properties of dissolved organic matter (DOM) are often studied in order to infer DOM characteristics in aquatic environments, including source, quantity, composition, and behavior. While a potentially powerful technique, a single widely implemented standard method for correcting and presenting fluorescence measurements is lacking, leading to difficulties when comparing data collected by different research groups. This paper reports on a large-scale interlaboratory comparison in which natural samples and well-characterized fluorophores were analyzed in 20 laboratories in the U.S., Europe, and Australia. Shortcomings were evident in several areas, including data quality-assurance, the accuracy of spectral correction factors used to correct EEMs, and the treatment of optically dense samples. Data corrected by participants according to individual laboratory procedures were more variable than when corrected under a standard protocol. Wavelength dependency in measurement precision and accuracy were observed within and between instruments, even in corrected data. In an effort to reduce future occurrences of similar problems, algorithms for correcting and calibrating EEMs are described in detail, and MATLAB scripts for implementing the study's protocol are provided. Combined with the recent expansion of spectral fluorescence standards, this approach will serve to increase the intercomparability of DOM fluorescence studies.

  19. Measuring the food environment: shelf space of fruits, vegetables, and snack foods in stores.

    PubMed

    Farley, Thomas A; Rice, Janet; Bodor, J Nicholas; Cohen, Deborah A; Bluthenthal, Ricky N; Rose, Donald

    2009-09-01

    Dietary patterns may be influenced by the availability and accessibility within stores of different types of foods. However, little is known about the amount of shelf space used for healthy and unhealthy foods in different types of stores. We conducted measurements of the length of shelf space used for fruits, vegetables, and snack foods items in 419 stores in 217 urban census tracts in southern Louisiana and in Los Angeles County. Although supermarkets offered far more shelf space of fruits and vegetables than did other types of stores, they also devoted more shelf space to unhealthy snacks (mean 205 m for all of these items combined) than to fruits and vegetables (mean 117 m, p < 0.001). After supermarkets, drug stores devoted the most shelf space to unhealthy items. The ratio of the total shelf space for fruits and vegetables to the total shelf space for these unhealthy snack items was the lowest (0.10 or below) and very similar in convenience stores, drug stores, and liquor stores, was in a middle range (0.18 to 0.30) in small food stores, and was highest in medium-sized food stores (0.40 to 0.61) and supermarkets (0.55 to 0.72). Simple measurements of shelf space can be used by researchers to characterize the healthfulness of the food environment and by policymakers to establish criteria for favorable policy treatment of stores. PMID:19603271

  20. Effectiveness of incentives for agri-environment measure in Mediterranean degraded and eroded vineyards

    NASA Astrophysics Data System (ADS)

    Galati, Antonino; Gristina, Luciano; Crescimanno, Maria; Barone, Ettore; Novara, Agata

    2015-04-01

    The evaluation of the economic damage caused by soil erosion assumes great importance. It serves to increase awareness of the problem among farmers and policy makers. Moreover, it can promote the implementation of conservative measures at the field and basin level by spurring the development of more sustainable soil management practices. In the present study we have developed a new approach to evaluate the incentive for the adoption of Agri-Environment Measure (AEM) in Mediterranean degraded and eroded vineyards. In order to estimate this incentive, the replacement cost and the loss of income are calculated under two different soil management such as Conventional Tillage (CT) and Cover crop (AEM). Our findings show that the incentive could range between the loss of income due to AEM adoption and ecosystem service benefit (RCCT - RC AEM). In the case of study the incentive ranged between 315 € ha-1 (loss of income) and 1,087.86 € ha-1 (Ecosystem service benefit). Within this range, the incentive amount is determined according to efficiency criteria taking into account the morphological conditions of the territory in which operate the farms. Moreover, a conceptual model on the public spending efficiency has been developed to allocate the incentives where the economic return in term of ecosystem service is higher.

  1. X-ray beam method for displacement measurement in hostile environments

    NASA Technical Reports Server (NTRS)

    Jordan, Eric H.; Pease, D. M.; Canistraro, H.; Brew, Dale

    1989-01-01

    A new method of extensometry using an X-ray beam was devised, and the results of current testing reveal it to be highly feasible. This technique has been shown to provide a non-contacting system that is immune to problems associated with density variations in gaseous environments, that plague currently available optical methods. This advantage is a result of the non-refracting penetrating nature of X-rays. The method is based on X-ray-induced X-ray fluorescence of targets, which subsequently serve as fudicial markers. Some target materials have melting points over 1600 degrees C which will facilitate measurement at extremely high temperatures. A highly focused intense X-ray beam, which is produced using a Johansen 'bent crystal', is then scanned across the target, which responds by fluorescing X-rays when stimulated by the incident beam. This secondary radiation is monitored using a detector. By carefully measuring beam orientation, change in target edge position can be determined. Many variations on this basic theme are now possible such as two targets demarcating a gage length, or a beam shadowing method using opaque targets.

  2. The use of autonomous unmanned vehicles for measuring the mean flow field in riverine environments

    NASA Astrophysics Data System (ADS)

    Tuggle, C.; Macmahan, J. H.; Brown, J.; Reniers, A. J.

    2010-12-01

    Autonomous unmanned vehicles (AUVs) are commonly used in oceanic, estuarine and, more recently, riverine environments because they are small, versatile, moving platforms equipped with a suite of instruments for measuring environmental conditions. However, moving vessel observations, particularly those associated acoustic Doppler current profiler (ADCP) observations, can be problematic owing to instrument noise, flow fluctuations, and spatial variability. As part of a riverine field experiment conducted in the Kootenai River, ID in August 2010, a spatial map of the mean horizontal and vertical velocity fields in a 200m wide, 8 m deep, and 0.5m/s meandering reach was obtained using two different AUV platforms: SeaRobotics unmanned surface vehicle (USV) and YSI/OceanServer Technology IVER-II unmanned underwater vehicle (UUV). The USV has dual-propellers navigating with GPS and was able to station-keep to within 1 m for 10 minutes at various locations within the reach in order to obtain the 3-D velocity field. Obtaining a statistically confident estimate of the mean velocity profile requires an appropriate time-interval to average instrument noise and environmental fluctuations. It has been previously proposed that 10 minutes is an adequate time interval when using an ADCP in a river. Preliminary results show that a shorter time interval is adequate, which would allow for increased spatial coverage. The UUV has a station-keeping capability when at the surface, but owing to its single propeller, it operates best by performing slow (0.2-0.35m/s) moving transects. Since the UUV is moving in a system that is spatially non-homogenous, additional errors in the mean velocity profile can be introduced due to spatial variability. An evaluation of the velocity profile quality, current measuring performance and minimum averaging time interval requirements are discussed for each platform, including the appropriate mission planning considerations for riverine observations. In

  3. Using MEMS sensor arrays to measure temperature at small spatial scales in hot spring environments

    NASA Astrophysics Data System (ADS)

    Oiler, J.; Schliep, K.; Hartnett, H. E.; Shock, E.; Yu, H.

    2011-12-01

    In situ measurement of temperature across the transition zones between chemosynthetic and photosynthetic microbial communities, or between different photosynthetic microbial communities in hot springs, can be ambiguous using current robust bulk measurement techniques due to the small spatial scale at of the transitions. Outflow channels are often narrow and shallow as they transport water away from the source, creating additional constraints on the size of the instrument and measurement technique used. Micro-Electro-Mechanical Systems (MEMS) technology is well-suited to take measurements of temperature within hot spring environments or other chemical parameters such as conductivity or pH. With recent advances in materials and fabrication techniques, devices can be fabricated to be chemically and thermally tolerant to the conditions present in the hot springs. The small size of the sensing elements (micron scale) provides the high spatial resolution necessary to interrogate the sharp transition zones between chemotrophic and photosynthetic communities. Owing to the small size of each sensor and the ability to batch-fabricate many sensors at once, an array of sensors can be made to measure a particular parameter simultaneously at short spatial intervals. Arrays of MEMS sensors were fabricated to measure temperature changes at intervals of ~1 cm. Our sensors consist of thermistors fabricated from a bi-layer of titanium and platinum. When heated, the electrical resistance of the thermistors will increase, and through calibration the resistance value is paired to a temperature value. The sensors and wires are covered with an inert biocompatible water-resistant polymer, Parylene-C, that protects them from chemical attack in the hot spring water. Using the arrays, a two-dimensional map of depth and distance was created at the Geothermal Explosion site in Tengchong, China, by placing the array vertically into a channel at spatial intervals of ~2 cm. Vertical measurements

  4. Combined Measurements of the Magnetic Field in the Plasma Environment of 67P/Churyumov-Gerasimenko

    NASA Astrophysics Data System (ADS)

    Koenders, Christoph; Richter, Ingo; Auster, Hans-Ulrich; Glassmeier, Karl-Heinz; Tsurutani, Bruce; Volwerk, Martin

    2014-05-01

    In 2004, the European spacecraft Rosetta was launched to a long journey to the comet 67P/Churyumov-Gerasimenko. Two magnetometers are among the different scientific instruments. One of them is mounted on the lander Philae and incorporated into the ROMAP package. The other one (RPC MAG) is part of the Rosetta Plasma Consortium (RPC) and located on a boom outside the orbiter. Both instruments are intended to study the plasma environment of the comet during the mission. As known from numerical simulations, this environment will change dramatically. In the early phase the activity of the comet will be low, and instead of a bow shock a Mach cone will be triggered. At this stage, Rosetta will arrive at the comet and the magnetometers will probably detect pick-up ion waves in the upstream region. In addition, the solar wind will penetrate the developing coma and reach the surface of the nucleus. Thus, our magnetometers will be able to study this situation for the first time ever. Furthermore, combined measurements of our magnetometers allow the characterisation of conductivity properties of the nucleus during the weak activity phase and a detection of a remanent magnetisation, possibly generated during formation of the comet. Later, the activity of the comet increases and the structures such as the cometary ionopause and the diamagnetic cavity will evolve. The two instruments will allow us to study these structures and their stabilities. We will present the design of the instruments and look forward to the next two years of unique magnetic field observations at the comet.

  5. A coupled sensor-spectrophotometric device for continuous measurement of formaldehyde in indoor environments.

    PubMed

    Carter, Ellison M; Jackson, Mark C; Katz, Lynn E; Speitel, Gerald E

    2014-01-01

    Despite long-standing awareness of adverse health effects associated with chronic human exposure to formaldehyde, this hazardous air pollutant remains a challenge to measure in indoor environments. Traditional analytical techniques evaluate formaldehyde concentrations over several hours to several days in a single location in a residence, making it difficult to characterize daily temporal and spatial variation in human exposure to formaldehyde. There is a need for portable, easy-to-use devices that are specific and sensitive to gas-phase formaldehyde over short sampling periods so that dynamic processes governing formaldehyde fate, transport, and potential remediation in indoor environments may be studied more effectively. A recently developed device couples a chemical sensor element with spectrophotometric analysis for detection and quantification of part per billion (ppbv) gas-phase formaldehyde concentrations. This study established the ability of the coupled sensor-spectrophotometric device (CSSD) to report formaldehyde concentrations accurately and continuously on a 30-min sampling cycle at low ppbv concentrations previously untested for this device in a laboratory setting. Determination of the method detection limit (MDL), based on 40 samples each at test concentrations of 5 and 10 ppbv, was found to be 1.9 and 2.0 ppbv, respectively. Performance of the CSSD was compared with the dinitrophenylhydrazine (DNPH) derivatization method for formaldehyde concentrations ranging from 5-50 ppbv, and a linear relationship with a coefficient of determination of 0.983 was found between these two analytical techniques. The CSSD was also used to monitor indoor formaldehyde concentrations in two manufactured homes. During this time, formaldehyde concentrations varied from below detection limit to 65 ppbv and were above the US National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit (REL) of 16 ppbv, which is also the exposure limit

  6. A miniaturized optical package for wall shear stress measurements in harsh environments

    NASA Astrophysics Data System (ADS)

    Chen, Tai-An; Mills, David; Chandrasekharan, Vijay; Sheplak, Mark

    2014-06-01

    We report the development of a time-resolved direct wall shear stress senor using an optical moiré transduction technique for harsh environments. The floating-element sensor is a lateral-position sensor that is micromachined to enable sufficient bandwidth and to minimize spatial aliasing. The optical transduction approach offers several advantages over electrical-based floating element techniques including immunity from electromagnetic interference and the ability to operate in a conductive fluid medium. Packaging for optical sensors presents significant challenges. The bulky nature and size of conventional free-space optics often limit their use to an optical test bench, making them unsuitable for harsh environments. The optical package developed in this research utilizes an array of optical fibers mapped over the moiré fringe. The fiber bundle approach results in a robust package that reduces the overall size of the optics, mitigates vibration between the sensor and optoelectronics and enables in situ measurement. The optical package for sampling the amplified moiré fringe is evaluated using bench top test setups. An optical test bench is constructed to simulate the movement of the moiré fringe on the floating element. High-resolution images of the optical fringe and optical fibers are combined in simulation to model the lateral displacement of the fringe. The performance of several fringe estimation algorithms are studied and evaluated. Based on the optical study, the optical package and post-processing algorithms are implemented on an actual device. Initial device characterization using this approach results in a device sensitivity of 12.4 nm/Pa.

  7. Conceptual design of a device to measure hand swelling in a micro-gravity environment

    NASA Technical Reports Server (NTRS)

    Hysinger, Christopher L.

    1993-01-01

    In the design of pressurized suits for use by astronauts in space, proper fit is an important consideration. One particularly difficult aspect of the suit design is the design of the gloves. If the gloves of the suit do not fit properly, the grip strength of the astronaut can be decreased by as much as fifty percent. These gloves are designed using an iterative process and can cost over 1.5 million dollars. Glove design is further complicated by the way the body behaves in a micro-gravity environment. In a micro-gravity setting, fluid from the lower body tends to move into the upper body. Some of this fluid collects in the hands and causes the hands to swell. Therefore, a pair of gloves that fit well on earth may not fit well when they are used in space. The conceptual design process for a device which can measure the swelling that occurs in the hands in a micro-gravity environment is described. This process involves developing a specifications list and function structure for the device and generating solution variants for each of the sub functions. The solution variants are then filtered, with the variants that violate any of the specifications being discarded. After acceptable solution variants are obtained, they are combined to form design concepts. These design concepts are evaluated against a set of criteria and the design concepts are ranked in order of preference. Through this process, the two most plausible design concepts were an ultrasonic imaging technique and a laser mapping technique. Both of these methods create a three dimensional model of the hand, from which the amount of swelling can be determined. In order to determine which of the two solutions will actually work best, a further analysis will need to be performed.

  8. MELIFT - A new device for accurate measurements in a snow rich environment

    NASA Astrophysics Data System (ADS)

    Dorninger, M.

    2012-04-01

    A deep snow pack, remote locations, no external power supply and very low temperatures are often the main ingredients when it comes to the deployment of meteorological stations in mountainous terrain. The accurate position of the sensor related to the snow surface is normally not known. A new device called METLIFT overcomes the problems. WMO recommends a height between 1.2 m and 2 m above ground level for the measurement of air temperature and humidity. The height above ground level is specified to take care of the possible strong vertical temperature and humidity gradients at the lowest layers in the atmosphere. Especially in snow rich and remote locations it may be hardly possible to follow this advice. Therefore most of the meteorological stations in mountainous terrain are situated at mountain tops where strong winds will blow off the snow or in valleys where a daily inspection of the sensors is possible. In other unpopulated mountainous areas, e.g. basins, plateaus, the distance of the sensor to the snow surface is not known or the sensor will be snow-covered. A new device was developed to guarantee the sensor height above surface within the WMO limits in harsh and remote environments. An ultrasonic snow height sensor measures the distance to the snow surface. If it exceeds certain limits due to snow accumulation or snow melt the lift adapts its height accordingly. The prototype of METLIFT has been installed in Lower Austria at an altitude of 1000m. The lift is 6 m high and can pull out for another 4 m. Sensor arms are mounted every meter to allow the connection of additional sensors or to measure a profile of a certain parameter of the lowest 5 m above surface. Sensors can be added easily since cable wiring is provided to each sensor arm. Horizontal winds are measured at 7 m height above surface. METLIFT is independent of external power supply. Three lead gel accumulators recharged by three solar panels provide the energy necessary for the sensors, the data

  9. Quantum Measurement of Two-Qubit System in Damping Noise Environment

    NASA Astrophysics Data System (ADS)

    Yang, Qing; Liu, Hui; Zhen, Xiu-Lan; Yang, Ming; Cao, Zhuo-Liang

    2016-03-01

    It is known that the inevitable interaction of the entangled qubits with their environments may result in the degradation of quantum correlation. We study the decoherence of two remote qubits under general local single- and two-sided amplitude-damping channel (ADC). By using concurrence, quantum discord and Clauser-Horne-Shimony-Holt (CHSH) inequality, we find that the relation between the residual quantum correlations and the initial ones are different. Recently, Wang et al. [Int. J. Theor. Phys. 54 (2015) 5] showed that there exist a set of partially entangled states that are more robust than maximally entangled states in terms of the residual quantum correlation measured by concurrence, fully entangled fraction and quantum discord, respectively. Here we find that both in single- and two-sided ADC, only the evolution of CHSH inequality with the initial parameter is proportional to that of the initial nonlocality. That means the initial state with maximally nonlocality will retain its role in the evolution. It implies that the evolution of nonlocality may reveal the characteristics of quantum state better. Furthermore, we discuss the evolutions of the three different quantum measurements with the initial parameter under generalized amplitude damping channel (GADC) and find that they are all proportional to that of the initial state. Supported by National Natural Science Foundation of China under Grant Nos. 11204002, 11274010, 61073048, 11005029, the Specialized Research Fund for the Doctoral Program of Higher Education (20123401120003, 20113401110002), the Key Project of Chinese Ministry of Education (Nos. 211080, 210092), the Key Program of the Education Department of Anhui Province under Grant No. KJ2012A020, the “211” Project of Anhui University, the Talent Foundation of Anhui University, the personnel department of Anhui province

  10. Quantum Measurement of Two-Qubit System in Damping Noise Environment

    NASA Astrophysics Data System (ADS)

    Qing, Yang; Hui, Liu; Xiu-Lan, Zhen; Ming, Yang; Zhuo-Liang, Cao

    2016-03-01

    It is known that the inevitable interaction of the entangled qubits with their environments may result in the degradation of quantum correlation. We study the decoherence of two remote qubits under general local single- and two-sided amplitude-damping channel (ADC). By using concurrence, quantum discord and Clauser–Horne–Shimony–Holt (CHSH) inequality, we find that the relation between the residual quantum correlations and the initial ones are different. Recently, Wang et al. [Int. J. Theor. Phys. 54 (2015) 5] showed that there exist a set of partially entangled states that are more robust than maximally entangled states in terms of the residual quantum correlation measured by concurrence, fully entangled fraction and quantum discord, respectively. Here we find that both in single- and two-sided ADC, only the evolution of CHSH inequality with the initial parameter is proportional to that of the initial nonlocality. That means the initial state with maximally nonlocality will retain its role in the evolution. It implies that the evolution of nonlocality may reveal the characteristics of quantum state better. Furthermore, we discuss the evolutions of the three different quantum measurements with the initial parameter under generalized amplitude damping channel (GADC) and find that they are all proportional to that of the initial state. Supported by National Natural Science Foundation of China under Grant Nos. 11204002, 11274010, 61073048, 11005029, the Specialized Research Fund for the Doctoral Program of Higher Education (20123401120003, 20113401110002), the Key Project of Chinese Ministry of Education (Nos. 211080, 210092), the Key Program of the Education Department of Anhui Province under Grant No. KJ2012A020, the “211” Project of Anhui University, the Talent Foundation of Anhui University, the personnel department of Anhui province

  11. Measurements of ultrafine particles carrying different number of charges in on- and near-freeway environments

    NASA Astrophysics Data System (ADS)

    Lee, Eon S.; Xu, Bin; Zhu, Yifang

    2012-12-01

    This paper presents measurements of electrical charges on ultrafine particles (UFPs) of different electrical mobility diameters (30, 50, 80, and 100 nm) in on- and near-freeway environments. Using a tandem Differential Mobility Analyzer (DMA) system, we first examined the fraction of UFPs carrying different number of charges on two distinctive freeways: a gasoline-vehicle dominated freeway (I-405) and a heavy-duty diesel truck dominated freeway (I-710). The fractions of UFPs of a given size carrying one or more charges were significantly higher on the freeways than in the background. The background UFPs only carried up to two charges but freeway UFPs could have up to three charges. The total fraction of charged particles was higher on the I-710 than I-405 across the studied electrical mobility diameters. Near the I-405 freeway, we observed a strong decay of charged particles on the downwind side of the freeway. We also found fractional decay of the charged particles was faster than total particle number concentrations, but slower than total ion concentrations downwind from the freeway I-405. Among charged particles, the highest decay rate was observed for particles carrying three charges. Near the I-710 freeway, we found strong net positive charges on nucleation mode particles, suggesting that UFPs were not at steady-state charge equilibrium near freeways.

  12. PV Ramping in a Distributed Generation Environment: A Study Using Solar Measurements; Preprint

    SciTech Connect

    Sengupta, M.; Keller, J.

    2012-06-01

    Variability in Photovoltaic (PV) generation resulting from variability in the solar radiation over the PV arrays is a topic of continuing concern for those involved with integrating renewables onto existing electrical grids. The island of Lanai, Hawaii is an extreme example of the challenges that integrators will face due to the fact that it is a small standalone grid. One way to study this problem is to take high-resolution solar measurements in multiple locations and model simultaneous PV production for various sizes at those locations. The National Renewable Energy Laboratory (NREL) collected high-resolution solar data at four locations on the island where proposed PV plants will be deployed in the near future. This data set provides unique insight into how the solar radiation may vary between points that are proximal in distance, but diverse in weather, due to the formation of orographic clouds in the center of the island. Using information about each proposed PV plant size, power output was created at high resolution. The team analyzed this output to understand power production ramps at individual locations and the effects of aggregating the production from all four locations. Hawaii is a unique environment, with extremely variable events occurring on a daily basis. This study provided an excellent opportunity for understanding potential worst-case scenarios for PV ramping. This paper provides an introduction to the datasets that NREL collected over a year and a comprehensive analysis of PV variability in a distributed generation scenario.

  13. Interferometric Tomographic Measurement of an Instataneous Flow Field Under Adverse Environments

    NASA Technical Reports Server (NTRS)

    Yu, En-Xi; Cha, Soyoung Stephen; Burner, Alpheus W.

    1995-01-01

    Measurement of an instantaneous flow field by interferometric tomography, that is, reconstruction of a three-dimensional refractive-index field from multi-directional projection data, has been conducted. In order to simulate the expected experimental arrangement at a wind tunnel, reconstructions are made from a restricted view angle less than 40 degrees and incomplete projections. In addition, appreciable ambient air and experimental setup disturbances are present. A new phase-stepping technique, based on a generalized phase-stepping approach of a four-bucket model, is applied for expeditious and accurate phase information extraction from projection interferograms under the harsh environments. Phase errors caused by the various disturbances, which can include ambient refractive-index change, optical component disturbance, hologram repositioning error, etc., are partially compensated with a linear corrective model. A new computational tomographic technique based on a series expansion approach was also utilized to efficiently deal with arbitrary boundary shapes and the continuous flow fields in reconstruction. The results of the preliminary investigation are encouraging; however, the technique needs to be further developed in the future through refinement of the approaches reported here and through hybridization with previously developed techniques. Keywords: interferometry, tomography, phase stepping

  14. Evolution of the sensor fish device for measuring physical conditions in sever hydraulic environments

    SciTech Connect

    Carlson, Thomas J.; Duncan, J. P.

    2003-03-01

    To assist in deriving biological specifications for design of turbine rehabilitation measures, new “fish-friendly” turbines, and spillway designs and operations, Pacific Northwest National Laboratory (PNNL) scientists have developed and tested an autonomous multi-sensor device called a Sensor Fish that can acquire pressure and tri-axial linear acceleration data during passage through severe hydraulic conditions. The purpose of the Sensor Fish is to characterize physical conditions fish experience during passage through hydro turbines, spill stilling basins, high-discharge outfalls, and other dam passage routes. This report discusses the development and field tests of the Sensor Fish at Rock Island, McNary, The Dalles, Bonneville, and Wanapum dams on the Columbia River and the Prosser Irrigation District on the Yakima River, which have shown that the device can withstand the severe environments of turbine, spill, and fish bypass passage and provide useful environmental data that can ultimately aid in the design and operation of new and existing turbines, spill, and dam fish bypass facilities.

  15. Evolution of the Sensor Fish Device for Measuring Physical Conditions in Severe Hydraulic Environments

    SciTech Connect

    Carlson, Thomas J.; Duncan, Joanne P.

    2003-02-28

    To assist in deriving biological specifications for design of turbine rehabilitation measures, new ''fish-friendly'' turbines, and spillway designs and operations, scientists at the Pacific Northwest National Laboratory (PNNL) have developed and tested an autonomous multi-sensor device called a Sensor Fish that can acquire pressure and tri-axial linear acceleration data during passage through severe hydraulic conditions. The purpose of the Sensor Fish is to characterize physical conditions fish experience during passage through hydro turbines, spill stilling basins, high-discharge outfalls, and other dam passage routes. The Sensor Fish was developed with the support of the U.S. Department of Energy's Advanced Hydropower Turbine System program. Field tests of the Sensor Fish at Rock Island, McNary, The Dalles, Bonneville, and Wanapum dams on the Columbia River and the Prosser Irrigation District on the Yakima River have shown that the device can withstand the severe environments of turbine, spill, and fish bypass passage and provide useful environmental data that can ultimately aid in the design and operation of new and existing turbines, spill, and dam fish bypass facilities.

  16. Long Term Trend in the LEO Radiation Environment as Measured by the Radiation Monitors On-Board Three UoSAT-Class Micro-Satellites

    NASA Astrophysics Data System (ADS)

    Underwood, C. I.; Oldfield, M. K.; Dyer, C. S., , Dr.

    1996-12-01

    Radiation environment monitoring payloads developed by DRA Farnborough and the University of Surrey have been flown on-board three low-Earth orbiting (LEO) microsatellites: UoSAT-3, KITSAT-1 and PoSAT-1. These have provided near-continuous sampling of the cosmic-ray and trapped proton environment inside the spacecraft since May 1990 - a period covering half a solar cycle {1,2,3,4}. This paper provides an analysis of the data from the payloads, and in particular examines the long term trends in the galactic cosmic-ray (GCR) background and trapped proton environment as experienced in LEO. These are then compared with predictions made using the standard environmental models available in the SPACE RADIATION code, together with our own PRISM code {5} to model particle transport and detector response. The results show good inter-correlation between the instruments, which were calibrated independently prior to flight using ion-beams, fission-fragments and alpha-sources. The trend in cosmic-ray background over the period has been generally upwards (as expected), and particle fluxes have doubled (in the LET-range of the instruments) over the six-year period. Fluxes are well correlated with the phase of the solar cycle. However, shorter-term features are observed which are not included in standard models. For example, there was a significant decrease in GCR following the major solar particle events of June 1991. This decrease persisted until late 1991. All the instruments showed a significant low-LET enhancement over the predictions made on the basis of standard models. The trapped proton environment shows long-term dynamics which are significantly out of phase with the solar cycle. The particle flux detected in the heart of the South-Atlantic anomaly reached a minimum in early-to-mid 1992, and has been increasing since then. This suggests that the phase of the trapped proton environment cycle might be better modelled on the basis of atmospheric density. Maps of the observed

  17. Characterization and measurement of qubit-environment-entanglement generation during pure dephasing

    NASA Astrophysics Data System (ADS)

    Roszak, Katarzyna; Cywiński, Łukasz

    2015-09-01

    We consider the coupling of a qubit in a pure state to an environment in an arbitrary state and characterize the possibility of qubit-environment-entanglement generation during the evolution of the joint system, that leads to pure dephasing of the qubit. We give a simple necessary and sufficient condition on the initial density matrix of the environment together with the properties of the interaction for the appearance of qubit-environment entanglement. Any entanglement created turns out to be detectable by the Peres-Horodecki criterion. Furthermore, we show that for a large family of initial environmental states, the appearance of nonzero entanglement with the environment is necessarily accompanied by a change in the state of the environment (i.e., by the backaction of the qubit).

  18. Measurements of Ground Acoustic Environments for Small Solid Rocket Motor Firings

    NASA Technical Reports Server (NTRS)

    Vu, Bruce; Plotkin, Ken

    2011-01-01

    Mobile launcher deck and tower are exposed to severe acoustic environments during launch. These environments, if not properly managed, can weaken ground support equipment and result in structure failure. The objectives of this study were: (1) Characterize the acoustic ground environment with and without water suppression systems. (2) Validate the ground acoustic prediction based on scaling of Saturn V data. and (3) Validate a semi-empirical acoustic analysis.

  19. Scenario analysis of Agro-Environment measure adoption for soil erosion protection in Sicilian vineyard (Italy)

    NASA Astrophysics Data System (ADS)

    Novara, Agata; Gristina, Luciano; Fantappiè, Maria; Costantini, Edoardo

    2014-05-01

    Most of the challenges in designing land use policies that address sustainability issues are inherent to the concept of Agro-Environmental Measures (AEM). Researchers, farmers and mainly policy makers need to evaluate the impact of new and existing policies for soil protection. In Europe, farmers commit themselves, for a minimum period of at least five years, to adopt environmentally-friendly farming techniques that undergone legal obligations. On the other hand, farmers receive payments that provide compensation for additional costs and income foregone resulting from applying those environmentally friendly farming practices in line with the stipulations of agri-environment contracts. In this context we prospect scenarios on soil erosion variations in a detailed case study after the application of Agro-Environmental Measures (AEM). The study area is located in the South part of Sicily. In a district area of 11,588 ha, 35.5 % is devoted to vineyard cultivation, 32.2 % is arable land and only 11.1 % cultivated to olive grow. 2416 ha are urbanized areas and other less important crops. A paired-site approach was chosen to study the difference in soil organic carbon stocks after AEM adoption, following criteria based on Conteh (1999) also applied in several research studies. For the purpose of comparison, the members of a paired site were selected to be similar with respect to the type of soil, slope, elevation, and drainage, but not to AEM. The comparisons were made between adjacent patches of land with different AEM, and a known history of land use and management. 100 paired sites (two adjacent plots) were chosen and three soil samples (0-30 cm depth) were collected in each plot (600 soil samples). The rainfall erosivity (R) factor (Mj mm ha-1 hour-1 year-1) was estimated with the formula specifically proposed for Sicily by Ferro and coauthors in 1999. The soil erodibility factor (K, in tons hour MJ-1 mm-1) was mapped on the base of soil texture and soil organic

  20. Branch enclosure BVOC flux measurements from Fagus sylvatica L. in a natural forest environment: preliminary results

    NASA Astrophysics Data System (ADS)

    Demarcke, M.; Amelynck, C.; Schoon, N.; Müller, J.-F.; Joo, E.; Dewulf, J.; van Langenhove, H.; Šimpraga, M.; Steppe, K.; Lemeur, R.; Samson, R.

    2009-04-01

    Natural ecosystems, such as forests, are known to be important sources of non-methane volatile organic compounds (NMVOCs). Oxidation of these biogenic VOCs (BVOCs) in the presence of nitrogen oxides can result in net ozone formation and the low-volatility oxidation products may contribute to secondary organic aerosol formation and/or growth. As a result BVOC emissions can have a negative effect on air quality and human health. In the commonly used emission algorithms [Guenther et al., 1995], leaf temperature and photosynthetic photon flux density (PPFD) are the driving variables for BVOC emissions. However, in order to better explain the variability over time of BVOC emissions for a given tree species, the most recent emission algorithms, such as MEGAN [Guenther et al., 2006], also consider other driving variables such as phenology, temperature and light history. To validate these new emission algorithms, dynamic branch enclosure BVOC flux measurements have been performed on an adult Fagus sylvatica L. tree in a natural forest environment under ambient PPFD and temperature conditions. Branches at different levels in the canopy were accessible from a 35 m high measurement tower. The cuvette air was analysed on-line with a hs-PTR-MS instrument, which was located in a log cabin at the bottom of the tower. Ion signals related to monoterpenoid compounds (m/z 81 and 137), isoprene (m/z 69), acetone (m/z 59) and methanol (m/z 33) have been measured continuously with the PTR-MS during several phenological periods, from bud-break to senescence. The data show high monoterpenoid emission rates in spring which gradually decrease until leaf fall. Furthermore, monoterpenoid emissions from shaded leaves in the lower layers of the canopy were found to be negligible compared to those from sunlit leaves in the upper layer of the canopy. Effects of light and temperature history on monoterpenoid emissions from Fagus sylvatica L. will be discussed and compared with results obtained in

  1. Physical priors in virtual colonoscopy

    NASA Astrophysics Data System (ADS)

    Rivaz, Hassan; Shinagawa, Yoshihisa; Liang, Jianming

    2009-02-01

    Electronic colon cleansing (ECC) aims to remove the contrast agent from the CT abdominal images so that a virtual model of the colon can be constructed. Virtual colonoscopy requires either liquid or solid preparation of the colon before CT imaging. This paper has two parts to address ECC in both preparation methods. In the first part, meniscus removal in the liquid preparation is studied. The meniscus is the curve seen at the top of a liquid in response to its container. Left on the colon wall, the meniscus can decrease the sensitivity and specificity of virtual colonoscopy. We state the differential equation that governs the profile of the meniscus and propose an algorithm for calculating the boundary of the contrast agent. We compute the surface tension of the liquid-colon wall contact using in-vivo CT data. Our results show that the surface tension can be estimated with an acceptable degree of uncertainty. Such an estimate, along with the meniscus profile differential equation will be used as an a priori knowledge to aid meniscus segmentation. In the second part, we study ECC in solid preparation of colon. Since the colon is pressurized with air before acquisition of the CT images, a prior on the shape of the colon wall can be obtained. We present such prior and investigate it using patient data. We show the shape prior is held in certain parts of the colon and propose a method that uses this prior to ease pseudoenhancement correction.

  2. Prior Distributions on Symmetric Groups

    ERIC Educational Resources Information Center

    Gupta, Jayanti; Damien, Paul

    2005-01-01

    Fully and partially ranked data arise in a variety of contexts. From a Bayesian perspective, attention has focused on distance-based models; in particular, the Mallows model and extensions thereof. In this paper, a class of prior distributions, the "Binary Tree," is developed on the symmetric group. The attractive features of the class are: it…

  3. Measuring Sports Class Learning Climates: The Development of the Sports Class Environment Scale

    ERIC Educational Resources Information Center

    Dowdell, Trevor; Tomson, L. Mich; Davies, Michael

    2011-01-01

    The development and validation of a new and unique learning climate instrument, the Sports Class Environment Scale (SCES), was the focus of this study. We began with a consolidation of the dimensions and items of the Perceived Motivational Climate in Sport Questionnaire-2 and the Classroom Environment Scale. Field-testing of the SCES involved 204…

  4. Objective measures of the built environment and physical activity in children: from walkability to moveability.

    PubMed

    Buck, Christoph; Tkaczick, Tobias; Pitsiladis, Yannis; De Bourdehaudhuij, Ilse; Reisch, Lucia; Ahrens, Wolfgang; Pigeot, Iris

    2015-02-01

    Features of the built environment that may influence physical activity (PA) levels are commonly captured using a so-called walkability index. Since such indices typically describe opportunities for walking in everyday life of adults, they might not be applicable to assess urban opportunities for PA in children. Particularly, the spatial availability of recreational facilities may have an impact on PA in children and should be additionally considered. We linked individual data of 400 2- to 9-year-old children recruited in the European IDEFICS study to geographic data of one German study region, based on individual network-dependent neighborhoods. Environmental features of the walkability concept and the availability of recreational facilities, i.e. playgrounds, green spaces, and parks, were measured. Relevant features were combined to a moveability index that should capture urban opportunities for PA in children. A gamma log-regression model was used to model linear and non-linear effects of individual variables on accelerometer-based moderate-to-vigorous physical activity (MVPA) stratified by pre-school children (<6 years) and school children (≥6 years). Single environmental features and the resulting indices were separately included into the model to investigate the effect of each variable on MVPA. In school children, commonly used features such as residential density [Formula: see text], intersection density [Formula: see text], and public transit density [Formula: see text] showed a positive effect on MVPA, while land use mix revealed a negative effect on MVPA [Formula: see text]. In particular, playground density [Formula: see text] and density of public open spaces, i.e., playgrounds and parks combined [Formula: see text], showed positive effects on MVPA. However, availability of green spaces showed no effect on MVPA. Different moveability indices were constructed based on the walkability index accounting for the negative impact of land use mix. Moveability

  5. An innovative experimental setup for Large Scale Particle Image Velocimetry measurements in riverine environments

    NASA Astrophysics Data System (ADS)

    Tauro, Flavia; Olivieri, Giorgio; Porfiri, Maurizio; Grimaldi, Salvatore

    2014-05-01

    Large Scale Particle Image Velocimetry (LSPIV) is a powerful methodology to nonintrusively monitor surface flows. Its use has been beneficial to the development of rating curves in riverine environments and to map geomorphic features in natural waterways. Typical LSPIV experimental setups rely on the use of mast-mounted cameras for the acquisition of natural stream reaches. Such cameras are installed on stream banks and are angled with respect to the water surface to capture large scale fields of view. Despite its promise and the simplicity of the setup, the practical implementation of LSPIV is affected by several challenges, including the acquisition of ground reference points for image calibration and time-consuming and highly user-assisted procedures to orthorectify images. In this work, we perform LSPIV studies on stream sections in the Aniene and Tiber basins, Italy. To alleviate the limitations of traditional LSPIV implementations, we propose an improved video acquisition setup comprising a telescopic, an inexpensive GoPro Hero 3 video camera, and a system of two lasers. The setup allows for maintaining the camera axis perpendicular to the water surface, thus mitigating uncertainties related to image orthorectification. Further, the mast encases a laser system for remote image calibration, thus allowing for nonintrusively calibrating videos without acquiring ground reference points. We conduct measurements on two different water bodies to outline the performance of the methodology in case of varying flow regimes, illumination conditions, and distribution of surface tracers. Specifically, the Aniene river is characterized by high surface flow velocity, the presence of abundant, homogeneously distributed ripples and water reflections, and a meagre number of buoyant tracers. On the other hand, the Tiber river presents lower surface flows, isolated reflections, and several floating objects. Videos are processed through image-based analyses to correct for lens

  6. The role of environment in the development of reading skills: a longitudinal study of preschool and school-age measures.

    PubMed

    Molfese, Victoria J; Modglin, Arlene; Molfese, Dennis L

    2003-01-01

    The purpose of this study was to extend previous studies on the influence of environmental measures on intelligence scores by examining how proximal and distal measures of children's environments in the preschool period and in the primary-grade period are related to their performance on reading achievement tests. Reading performance was explored using two approaches. The first approach involved the identification of children within a longitudinal sample who had poor reading skills at 8 years of age. The second approach used the full range of reading scores to explore whether factors influencing poor reading were different from those influencing good reading. Participants were 113 children, including 35 children with poor reading skills, who were part of a longitudinal study of cognitive development. Socioeconomic status (SES), Home Observation for Measurement of the Environment (HOME) scores at 3 and 10 years of age, and school-administered and individually administered reading achievement scores were obtained. Both SES and HOME scores were found to be related to reading abilities, but preschool environment measures were more strongly and consistently related to and predictive of reading scores. Differences in the patterns of correlations and the results of the predictive models were found between the full sample and the poor readers. Variables other than proximal and distal measures of the environment are involved in the development of reading skills. PMID:15490892

  7. Color measurements on marble and limestone briquettes exposed to outdoor environment in the Eastern United States. Volume I: Results of exposure 1984-1990

    SciTech Connect

    Reimann, K.J.

    1994-04-01

    In a long-term program that began in 1984, limestone and marble briquettes have been exposed to both anthropogenic acid deposition and natural weathering at four field sites in the eastern United States. Similar tests began at an Ohio site in 1986. Effects of exposure on the briquettes and other materials at the sites are evaluated periodically by several federal agencies cooperating in the National Acid Precipitation Assessment Program (NAPAP). One of the primary contributions of Argonne National Laboratory to the NAPAP has been the measurement of tristimulus color change on samples exposed to the environment. Results from the first six years indicate a yellowing of the marble and a darkening of limestone on both the skyward and groundward surfaces of fresh and preexposed briquettes. The relationship between discoloration and exposure period appears to be linear. Discoloration rates as a function of a cumulative exposure time are almost constant for marble and slightly decreasing for limestone Dark spots on groundward surfaces were measured with tristimulus color equipment prior to chemical analysis to determine if a correlation exists between darkening (change in reflectance) and SO{sub 4} concentration. Taking exposure time into consideration, and assuming that the airborne concentration of dark particles, which cause darkening, is proportional to airborne SO{sub 2} concentration, one can establish a linear relationship between exposure time, darkening, and SO{sub 2} concentration. The program is continuing so that additional data can be obtained.

  8. Shuffler calibration and measurement of mixtures of uranium and plutonium TRU-waste in a plant environment

    SciTech Connect

    Hurd, J.R.

    1998-12-31

    The active-passive shuffler installed and certified a few years ago in Los Alamos National Laboratory`s plutonium facility has now been calibrated for different matrices to measure Waste Isolation Pilot Plant (WIPP)-destined transuranic (TRU)-waste. Little or no data presently exist for these types of measurements in plant environments where there may be sudden large changes in the neutron background radiation which causes distortions in the results. Measurements and analyses of twenty-two 55-gallon drums, consisting of mixtures of varying quantities of uranium and plutonium, have been recently completed at the plutonium facility. The calibration and measurement techniques, including the method used to separate out the plutonium component, will be presented and discussed. Particular attention will be directed to those problems identified as arising from the plant environment. The results of studies to quantify the distortion effects in the data will be presented. Various solution scenarios will be indicated, along with those adopted here.

  9. Methods to measure indicators of exposure in real-world aquatic environments

    EPA Science Inventory

    Most of what is known about the implications of endocrine disrupting chemicals in the environment is somewhat anecdotal. There are numerous reports of gonadal histological abnormalities (Potomac, United Kingdom Rivers), alterations in sex ratios (Boulder Creek, Colorado) and high...

  10. Measuring the effect of patient comfort rounds on practice environment and patient satisfaction: a pilot study.

    PubMed

    Gardner, Glenn; Woollett, Kaylene; Daly, Naomi; Richardson, Bronwyn

    2009-08-01

    Hourly rounding in the acute hospital setting has been proposed as an intervention to increase patient satisfaction and safety, and improve the nursing practice environment, but the innovation has not been adequately tested. A quasi-experimental pretest post-test non-randomized parallel group trial design was used to test the effect of hourly patient comfort rounds on patient satisfaction and nursing perceptions of the practice environment, and to evaluate research processes and instruments for a proposed larger study. A Patient Satisfaction Survey instrument was developed and used in conjunction with the Practice Environment Scale of the Nursing Work Index. Results on patient satisfaction showed no significant changes. Significant changes were found for three of the five practice environment subscales. Consistent with the aim of a pilot study, this research has provided important information related to design, instruments and process that will inform a larger sufficiently powered study. PMID:19703045

  11. Measurements of the SEE environment from sea level to GEO using the CREAM and CREDO experiments

    SciTech Connect

    Dyer, C.S.; Sims, A.; Underwood, C.

    1996-04-01

    The cosmic radiation environment and activation monitor (CREAM) and cosmic radiation environment and dosimetry (CREDO) experiments have now been employed in a wide range of flight situations including aircraft, space shuttle, UOSAT spacecraft, and most recently the advanced photovoltaics and electronics experiment (APEX) and space technology research vehicle (STRV) satellites. Results from this unique coverage of the environment will be given ranging from the atmosphere, through the radiation belts to geostationary orbit. Collateral data on upsets have also been obtained for a number of situations. Comparisons are made with standard environment and SEE models and show significant deficiencies and discrepancies. These include time variations in the trapped particles, new radiation belts, secondary particle effects in both heavy spacecraft and the atmosphere, and overestimates of cosmic ray and solar flare heavy ions. The need for both further developments in the models and a comprehensive program of flight experiments is emphasized.

  12. Genomic Measures to Predict Adaptation to Novel Sensorimotor Environments and Improve Personalization of Countermeasure Design

    NASA Technical Reports Server (NTRS)

    Kreutzberg, G. A.; Zanello, S.; Seidler, R. D.; Peters, B.; De Dios, Y. E.; Gadd, N. E.; Bloomberg, J. J.; Mulavara, A. P.

    2016-01-01

    Introduction. Astronauts experience sensorimotor disturbances during their initial exposure to microgravity and during the re-adaptation phase following a return to an Earth-gravitational environment. These alterations may affect crewmembers' ability to perform mission-critical functional tasks. Interestingly, astronauts have shown significant inter-subject variation in adaptive capability during gravitational transitions. The ability to predict the manner and degree to which individual astronauts would be affected would improve the efficacy of personalized countermeasure training programs designed to enhance sensorimotor adaptability. The success of such an approach depends on the development of predictive measures of sensorimotor adaptation, which would ascertain each crewmember's adaptive capacity. The goal of this study is to determine whether specific genetic polymorphisms have significant influence on sensorimotor adaptability, which can help inform the design of personalized training countermeasures. Methods. Subjects (n=15) were tested on their ability to negotiate a complex obstacle course for ten test trials while wearing up-down vision-displacing goggles. This presented a visuomotor challenge while doing a full body task. The first test trial time and the recovery rate over the ten trials were used as adaptability performance metrics. Four single nucleotide polymorphisms (SNPs) were selected for their role in neural pathways underlying sensorimotor adaptation and were identified in subjects' DNA extracted from saliva samples: catechol-O-methyl transferase (COMT, rs4680), dopamine receptor D2 (DRD2, rs1076560), brain-derived neurotrophic factor genes (BDNF, rs6265), and the DraI polymorphism of the alpha-2 adrenergic receptor. The relationship between the SNPs and test performance was assessed by assigning subjects a rank score based on their adaptability performance metrics and comparing gene expression between the top half and bottom half performers

  13. Radioactivity in the Kuwait marine environment--Baseline measurements and review.

    PubMed

    Uddin, S; Aba, A; Fowler, S W; Behbehani, M; Ismaeel, A; Al-Shammari, H; Alboloushi, A; Mietelski, J W; Al-Ghadban, A; Al-Ghunaim, A; Khabbaz, A; Alboloushi, O

    2015-11-30

    The Arabian Gulf region is moving towards a nuclear energy option with the first nuclear power plant now operational in Bushehr, Iran, and others soon to be constructed in Abu Dhabi and Saudi Arabia. Radiological safety is becoming a prime concern in the region. This study compiles available data and presents recent radionuclide data for the northern Gulf waters, considered as pre-nuclear which will be a valuable dataset for future monitoring work in this region. Radionuclide monitoring in the marine environment is a matter of prime concern for Kuwait, and an assessment of the potential impact of radionuclides requires the establishment and regular updating of baseline levels of artificial and natural radionuclides in various environmental compartments. Here we present baseline measurements for (210)Po, (210)Pb, (137)Cs, (90)Sr, and (3)H in Kuwait waters. The seawater concentration of (3)H, (210)Po, (210)Pb, (137)Cs, and (90)Sr vary between 130-146, 0.48-0.68, 0.75-0.89, 1.25-1.38 and 0.57-0.78 mBq L(-1), respectively. The (40)K concentration in seawater varies between 8.9-9.3 Bq L(-1). The concentration of (40)K, total (210)Pb, (137)Cs, (90)Sr, (226)Ra, (228)Ra, (238)U, (235)U, (234)U, (239+240)Pu and (238)Pu were determined in sediments and range, respectively, between 353-445, 23.6-44.3, 1.0-3.1, 4.8-5.29, 17.3-20.5, 15-16.4, 28.7-31.4, 1.26-1.30, 29.7-30.0, 0.045-0.21 and 0.028-0.03 Bq kg(-1) dry weight. Since, radionuclides are concentrated in marine biota, a large number of marine biota samples covering several trophic levels, from microalgae to sharks, were analyzed. The whole fish concentration of (40)K, (226)Ra, (224)Ra, (228)Ra, (137)Cs, (210)Po and (90)Sr range between 230-447, 0.7-7.3, <0.5-6.6, <0.5-15.80, <0.17, 0.88-4.26 and 1.86-5.34 Bq kg(-1) dry weight, respectively. (210)Po was found to be highly concentrated in several marine organisms with the highest (210)Po concentration found in Marica marmorata (193.5-215.6 Bq kg(-1) dry weight). (210)Po in

  14. Measuring psychosocial environments using individual responses: an application of multilevel factor analysis to examining students in schools.

    PubMed

    Dunn, Erin C; Masyn, Katherine E; Jones, Stephanie M; Subramanian, S V; Koenen, Karestan C

    2015-07-01

    Interest in understanding how psychosocial environments shape youth outcomes has grown considerably. School environments are of particular interest to prevention scientists as many prevention interventions are school-based. Therefore, effective conceptualization and operationalization of the school environment is critical. This paper presents an illustration of an emerging analytic method called multilevel factor analysis (MLFA) that provides an alternative strategy to conceptualize, measure, and model environments. MLFA decomposes the total sample variance-covariance matrix for variables measured at the individual level into within-cluster (e.g., student level) and between-cluster (e.g., school level) matrices and simultaneously models potentially distinct latent factor structures at each level. Using data from 79,362 students from 126 schools in the National Longitudinal Study of Adolescent to Adult Health (formerly known as the National Longitudinal Study of Adolescent Health), we use MLFA to show how 20 items capturing student self-reported behaviors and emotions provide information about both students (within level) and their school environment (between level). We identified four latent factors at the within level: (1) school adjustment, (2) externalizing problems, (3) internalizing problems, and (4) self-esteem. Three factors were identified at the between level: (1) collective school adjustment, (2) psychosocial environment, and (3) collective self-esteem. The finding of different and substantively distinct latent factor structures at each level emphasizes the need for prevention theory and practice to separately consider and measure constructs at each level of analysis. The MLFA method can be applied to other nested relationships, such as youth in neighborhoods, and extended to a multilevel structural equation model to better understand associations between environments and individual outcomes and therefore how to best implement preventive interventions

  15. Measuring Psychosocial Environments Using Individual Responses: an Application of Multilevel Factor Analysis to Examining Students in Schools

    PubMed Central

    Masyn, Katherine E.; Jones, Stephanie M.; Subramanian, S. V.; Koenen, Karestan C.

    2015-01-01

    Interest in understanding how psychosocial environments shape youth outcomes has grown considerably. School environments are of particular interest to prevention scientists as many prevention interventions are school-based. Therefore, effective conceptualization and operationalization of the school environment is critical. This paper presents an illustration of an emerging analytic method called multilevel factor analysis (MLFA) that provides an alternative strategy to conceptualize, measure, and model environments. MLFA decomposes the total sample variance-covariance matrix for variables measured at the individual level into within-cluster (e.g., student level) and between-cluster (e.g., school level) matrices and simultaneously models potentially distinct latent factor structures at each level. Using data from 79,362 students from 126 schools in the National Longitudinal Study of Adolescent to Adult Health (formerly known as the National Longitudinal Study of Adolescent Health), we use MLFA to show how 20 items capturing student self-reported behaviors and emotions provide information about both students (within level) and their school environment (between level). We identified four latent factors at the within level: (1) school adjustment, (2) externalizing problems, (3) internalizing problems, and (4) self-esteem. Three factors were identified at the between level: (1) collective school adjustment, (2) psychosocial environment, and (3) collective self-esteem. The finding of different and substantively distinct latent factor structures at each level emphasizes the need for prevention theory and practice to separately consider and measure constructs at each level of analysis. The MLFA method can be applied to other nested relationships, such as youth in neighborhoods, and extended to a multilevel structural equation model to better understand associations between environments and individual outcomes and therefore how to best implement preventive interventions

  16. Predicting a prior for Planck

    SciTech Connect

    Hertog, Thomas

    2014-02-01

    The quantum state of the universe combined with the structure of the landscape potential implies a prior that specifies predictions for observations. We compute the prior for CMB related observables given by the no-boundary wave function (NBWF) in a landscape model that includes a range of inflationary patches representative of relatively simple single-field models. In this landscape the NBWF predicts our classical cosmological background emerges from a region of eternal inflation associated with a plateau-like potential. The spectra of primordial fluctuations on observable scales are characteristic of concave potentials, in excellent agreement with the Planck data. By contrast, alternative theories of initial conditions that strongly favor inflation at high values of the potential are disfavored by observations in this landscape.

  17. Image Reconstruction Using Analysis Model Prior.

    PubMed

    Han, Yu; Du, Huiqian; Lam, Fan; Mei, Wenbo; Fang, Liping

    2016-01-01

    The analysis model has been previously exploited as an alternative to the classical sparse synthesis model for designing image reconstruction methods. Applying a suitable analysis operator on the image of interest yields a cosparse outcome which enables us to reconstruct the image from undersampled data. In this work, we introduce additional prior in the analysis context and theoretically study the uniqueness issues in terms of analysis operators in general position and the specific 2D finite difference operator. We establish bounds on the minimum measurement numbers which are lower than those in cases without using analysis model prior. Based on the idea of iterative cosupport detection (ICD), we develop a novel image reconstruction model and an effective algorithm, achieving significantly better reconstruction performance. Simulation results on synthetic and practical magnetic resonance (MR) images are also shown to illustrate our theoretical claims. PMID:27379171

  18. Image Reconstruction Using Analysis Model Prior

    PubMed Central

    Han, Yu; Du, Huiqian; Lam, Fan; Mei, Wenbo; Fang, Liping

    2016-01-01

    The analysis model has been previously exploited as an alternative to the classical sparse synthesis model for designing image reconstruction methods. Applying a suitable analysis operator on the image of interest yields a cosparse outcome which enables us to reconstruct the image from undersampled data. In this work, we introduce additional prior in the analysis context and theoretically study the uniqueness issues in terms of analysis operators in general position and the specific 2D finite difference operator. We establish bounds on the minimum measurement numbers which are lower than those in cases without using analysis model prior. Based on the idea of iterative cosupport detection (ICD), we develop a novel image reconstruction model and an effective algorithm, achieving significantly better reconstruction performance. Simulation results on synthetic and practical magnetic resonance (MR) images are also shown to illustrate our theoretical claims. PMID:27379171

  19. Surgical Theatre (Operating Room) Measure STEEM (OREEM) Scoring Overestimates Educational Environment: The 1-to-L Bias

    ERIC Educational Resources Information Center

    Dimoliatis, Ioannis D. K.; Jelastopulu, Eleni

    2013-01-01

    The surgical theatre educational environment measures STEEM, OREEM and mini-STEEM for students (student-STEEM) comprise an up to now disregarded systematic overestimation (OE) due to inaccurate percentage calculation. The aim of the present study was to investigate the magnitude of and suggest a correction for this systematic bias. After an…

  20. The Resource-Infrastructure-Environment Index for Measuring Progress: An Application to Australia, Mexico and the US

    ERIC Educational Resources Information Center

    Natoli, Riccardo; Zuhair, Segu

    2013-01-01

    The resource-infrastructure-environment (RIE) index was proposed as an alternative measure of progress which was then employed to: (1) compare the aggregate (single summary) index findings between Australia (mid-industrialised nation), Mexico (emerging economy), and the US (highly industrialised nation); and (2) compare the RIE index against the…

  1. Characterization and exposure measurement for indium oxide nanofibers generated as byproducts in the LED manufacturing environment.

    PubMed

    Choi, Kwang-Min; An, Hee-Chul

    2016-01-01

    This article aimed to elucidate the physicochemical characteristics and exposure concentration of powder and airborne particles as byproducts generated from indium tin oxide thin film process by an electron beam evaporation method during maintenance in light-emitting diode manufacturing environment. The chemical composition, size, shape, and crystal structure of powder and airborne particles as byproducts were investigated using a scanning electron microscope equipped with energy dispersive spectrometer, and an X-ray diffractometer. The number and mass concentration measurements of airborne particles were performed by using an optical particle counter of direct-reading aerosol monitor and an inductively coupled plasma-mass spectrometry after sampling, respectively. The airborne particles are composed of oxygen and indium. On the other hand, the powder byproducts consist mostly of oxygen and indium, but tin was found as a minor component. The shapes of the airborne and powder byproducts were fiber type. The length and diameter of fibrous particles were approximately 500-2,000 nm and 30-50 nm, respectively. The powder byproducts indicated indium oxide nanofibers with a rhombohedral structure. On the other hand, the indium oxide used as a source material in the preparation of ITO target showed spherical morphology with a body-centered cubic structure, and it was the same as that of the pure crystalline indium oxide powder. During maintenance, the number concentrations ranged from 350-75,693 particles/ft(3), and arithmetic mean±standard deviation and geometric mean±geometric standard deviation were 11,624±15,547 and 4,846±4.12 particles/ft(3), respectively. Meanwhile, under the same conditions, the airborne mass concentrations of the indium based on respirable particle size (3.5 µm cut-point 50%) were 0.09-0.19 µg/m(3). Physicochemical characteristics of nanoparticle can affect toxicity so the fact that shape and crystal structure have changed is important. Thus

  2. Measuring the Interestingness of Articles in a Limited User Environment Prospectus

    SciTech Connect

    Pon, R K

    2007-04-18

    Search engines, such as Google, assign scores to news articles based on their relevancy to a query. However, not all relevant articles for the query may be interesting to a user. For example, if the article is old or yields little new information, the article would be uninteresting. Relevancy scores do not take into account what makes an article interesting, which would vary from user to user. Although methods such as collaborative filtering have been shown to be effective in recommendation systems, in a limited user environment there are not enough users that would make collaborative filtering effective. I present a general framework for defining and measuring the ''interestingness'' of articles, called iScore, incorporating user-feedback including tracking multiple topics of interest as well as finding interesting entities or phrases in a complex relationship network. I propose and have shown the validity of the following: 1. Filtering based on only topic relevancy is insufficient for identifying interesting articles. 2. No single feature can characterize the interestingness of an article for a user. It is the combination of multiple features that yields higher quality results. For each user, these features have different degrees of usefulness for predicting interestingness. 3. Through user-feedback, a classifier can combine features to predict interestingness for the user. 4. Current evaluation corpora, such as TREC, do not capture all aspects of personalized news filtering systems necessary for system evaluation. 5. Focusing on only specific evolving user interests instead of all topics allows for more efficient resource utilization while yielding high quality recommendation results. 6. Multiple profile vectors yield significantly better results than traditional methods, such as the Rocchio algorithm, for identifying interesting articles. Additionally, the addition of tracking multiple topics as a new feature in iScore, can improve iScore's classification

  3. Physical, consumer, and social aspects of measuring the food environment among diverse low-income populations.

    PubMed

    Gittelsohn, Joel; Sharma, Sangita

    2009-04-01

    Obesity and other diet-related chronic diseases are directly related to the food environment. We describe how to better assess the food environment in specific ethnic minority settings for designing and implementing interventions, based on a review of our previous work on the food environment in American Indian reservations, Canadian First Nations reserves, the Republic of the Marshall Islands, and inner-city Baltimore. The types of food stores available within each setting and the range of healthy foods available varied greatly across these geographic regions. In all settings, proximity to food stores/supermarkets, cost, and limited availability of healthful foods were common features, which limited access to health-promoting food options. Features specific to each population should be considered in an assessment of the food environment, including physical (e.g., openness of stores, mix of types of food sources); consumer (e.g., adequacy of the food supply, seasonal factors); and social (e.g., inter-household food sharing, perceptions of food quality, language differences) aspects. The food environments common in low-income ethnic subpopulations require special focus and consideration due to the vulnerability of the populations and to specific and unique aspects of each setting. PMID:19285208

  4. Information Propagation in Prior-Image-Based Reconstruction

    PubMed Central

    Stayman, J. Webster; Prince, Jerry L.; Siewerdsen, Jeffrey H.

    2016-01-01

    Advanced reconstruction methods for computed tomography include sophisticated forward models of the imaging system that capture the pertinent physical processes affecting the signal and noise in projection measurements. However, most do little to integrate prior knowledge of the subject – often relying only on very general notions of local smoothness or edges. In many cases, as in longitudinal surveillance or interventional imaging, a patient has undergone a sequence of studies prior to the current image acquisition that hold a wealth of prior information on patient-specific anatomy. While traditional techniques tend to treat each data acquisition as an isolated event and disregard such valuable patient-specific prior information, some reconstruction methods, such as PICCS[1] and PIR-PLE[2], can incorporate prior images into a reconstruction objective function. Inclusion of such information allows for dramatic reduction in the data fidelity requirements and more robustly accommodate substantial undersampling and exposure reduction with consequent benefits to imaging speed and reduced radiation dose. While such prior-image-based methods offer tremendous promise, the introduction of prior information in the reconstruction raises significant concern regarding the accurate representation of features in the image and whether those features arise from the current data acquisition or from the prior images. In this work we propose a novel framework to analyze the propagation of information in prior-image-based reconstruction by decomposing the estimation into distinct components supported by the current data acquisition and by the prior image. This decomposition quantifies the contributions from prior and current data as a spatial map and can trace specific features in the image to their source. Such “information source maps” can potentially be used as a check on confidence that a given image feature arises from the current data or from the prior and to more

  5. The influence of urban natural and built environments on physiological and psychological measures of stress--a pilot study.

    PubMed

    Beil, Kurt; Hanes, Douglas

    2013-04-01

    Environments shape health and well-being, yet little research has investigated how different real-world environmental settings influence the well-known determinant of health known as stress. Using a cross-over experimental design; this pilot study investigated the effect of four urban environments on physiological and psychological stress measures. Participants (N = 15) were exposed on separate days to one of the four settings for 20 min. These settings were designated as Very Natural; Mostly Natural; Mostly Built and Very Built. Visitation order to the four settings was individually randomized. Salivary cortisol and alpha-amylase; as well as self-report measures of stress; were collected before and after exposure to each setting. Gender was included as a variable in analysis; and additional data about environmental self-identity, pre-existing stress, and perceived restorativeness of settings were collected as measures of covariance. Differences between environmental settings showed greater benefit from exposure to natural settings relative to built settings; as measured by pre-to-post changes in salivary amylase and self-reported stress; differences were more significant for females than for males. Inclusion of covariates in a regression analysis demonstrated significant predictive value of perceived restorativeness on these stress measures, suggesting some potential level of mediation. These data suggest that exposure to natural environments may warrant further investigation as a health promotion method for reducing stress. PMID:23531491

  6. The Influence of Urban Natural and Built Environments on Physiological and Psychological Measures of Stress—A Pilot Study

    PubMed Central

    Beil, Kurt; Hanes, Douglas

    2013-01-01

    Environments shape health and well-being, yet little research has investigated how different real-world environmental settings influence the well-known determinant of health known as stress. Using a cross-over experimental design; this pilot study investigated the effect of four urban environments on physiological and psychological stress measures. Participants (N = 15) were exposed on separate days to one of the four settings for 20 min. These settings were designated as Very Natural; Mostly Natural; Mostly Built and Very Built. Visitation order to the four settings was individually randomized. Salivary cortisol and alpha-amylase; as well as self-report measures of stress; were collected before and after exposure to each setting. Gender was included as a variable in analysis; and additional data about environmental self-identity, pre-existing stress, and perceived restorativeness of settings were collected as measures of covariance. Differences between environmental settings showed greater benefit from exposure to natural settings relative to built settings; as measured by pre-to-post changes in salivary amylase and self-reported stress; differences were more significant for females than for males. Inclusion of covariates in a regression analysis demonstrated significant predictive value of perceived restorativeness on these stress measures, suggesting some potential level of mediation. These data suggest that exposure to natural environments may warrant further investigation as a health promotion method for reducing stress. PMID:23531491

  7. Measurements of solar flare enhancements to the single event upset environment in the upper atmosphere

    NASA Astrophysics Data System (ADS)

    Dyer, C. S.; Sims, A. J.; Farren, J.; Stephen, J.

    1990-12-01

    The Cosmic Radiation Environment Monitor has flow regularly on a supersonic airliner over a period of 18 months in order to explore the extent of single-event phenomena in the upper atmosphere. Data presented are from flights occurring between November 1988 and May 1990. The detector system used is briefly described. Quiet-time data now have good statistical precision and are compared with predictions of environment models. A number of increases and decreases were observed during the solar flare events of September and October 1989.

  8. [Research on accurate measurement of oxygen content in coal using laser-induced breakdown spectroscopy in air environment].

    PubMed

    Yin, Wang-bao; Zhang, Lei; Wang, Le; Dong, Lei; Ma, Wei-guang; Jia, Suo-tang

    2012-01-01

    A technique about accurate measurement of oxygen content in coal in air environment using laser-induced breakdown spectroscopy (LIBS) is introduced in the present paper. Coal samples were excited by the laser, and plasma spectra were obtained. Combining internal standard method, temperature correction method and multi-line methods, the oxygen content of coal samples was precisely measured. The measurement precision is not less than 1.37% for oxygen content in coal analysis, so is satisfied for the requirement of coal-fired power plants in coal analysis. This method can be used in surveying, environmental protection, medicine, materials, archaeological and food safety, biochemical and metallurgy application. PMID:22497159

  9. Mechanical impedance and acoustic mobility measurement techniques of specifying vibration environments

    NASA Technical Reports Server (NTRS)

    Kao, G. C.

    1973-01-01

    Method has been developed for predicting interaction between components and corresponding support structures subjected to acoustic excitations. Force environments determined in spectral form are called force spectra. Force-spectra equation is determined based on one-dimensional structural impedance model.

  10. Detection of Silver Nanoparticles in Vadose Zone Environments using Complex ConductivityMeasurements

    EPA Science Inventory

    The emergence of engineered nano-materials (ENMs) in the global marketplace and their accidental introduction into the subsurface pose a potential risk to the environment and public health. There is a need for the development of techniques to detect their presence and transport i...

  11. Measuring the Effectiveness of Blended Learning Environment: A Case Study in Malaysia

    ERIC Educational Resources Information Center

    Wai, Cho Cho; Seng, Ernest Lim Kok

    2015-01-01

    Learning environment has always been traditionally associated with the physical presence of classrooms, textbooks, pen-and-paper examinations and teachers. However, today's evolving technology has rapidly changed the face of education. Online learning, teleconferencing, internet, Computer Assisted Learning (CAL), Web-Based Distance Learning (WBDL)…

  12. UP OR OUT: MEASURING AND MODELING THE GROWTH OF CHINA’S BUILT ENVIRONMENT

    EPA Science Inventory

    Enormous population and income increases in China’s urban centers are expected drive the built environment both upward and outward. However, the density of urban development is expected to vary considerably across regions, particularly in the context of heterogeneous land ...

  13. Nature and Nurture: Genetic Contributions to Measures of the Family Environment.

    ERIC Educational Resources Information Center

    Plomin, Robert; And Others

    1994-01-01

    This study of 707 sibling pairs, 10- to 18-years-old, examined parent-child and sibling interactions to determine the effects of genetics on family environment. The sample included identical and fraternal twins and full siblings in nondivorced families, as well as full, half, and unrelated siblings in divorced families. Found significant genetic…

  14. Measuring Flow Experience in an Immersive Virtual Environment for Collaborative Learning

    ERIC Educational Resources Information Center

    van Schaik, P.; Martin, S.; Vallance, M.

    2012-01-01

    In contexts other than immersive virtual environments, theoretical and empirical work has identified flow experience as a major factor in learning and human-computer interaction. Flow is defined as a "holistic sensation that people feel when they act with total involvement". We applied the concept of flow to modeling the experience of…

  15. School Policy on Teaching and School Learning Environment: Direct and Indirect Effects upon Student Outcome Measures

    ERIC Educational Resources Information Center

    Kyriakides, Leonidas; Creemers, Bert P. M.

    2012-01-01

    School policy on teaching and the school learning environment (SLE) are the main school factors of the dynamic model of educational effectiveness (Creemers & Kyriakides, 2008). A longitudinal study in which 50 primary schools, 108 classes, and 2369 students participated generated evidence supporting the validity of the dynamic model. This article…

  16. The 1992 NASA Langley Measurement Technology Conference: Measurement Technology for Aerospace Applications in High-Temperature Environments

    NASA Technical Reports Server (NTRS)

    Singh, Jag J. (Editor); Antcliff, Richard R. (Editor)

    1992-01-01

    An intensive 2-day conference to discuss the current status of measurement technology in the areas of temperature/heat flux, stress/strain, pressure, and flowfield diagnostics for high temperature aerospace applications was held at Langley Research Center, Hampton, Virginia, on April 22 and 23, 1993. Complete texts of the papers presented at the Conference are included in these proceedings.

  17. Comparative Measurements of Earth and Martian Entry Environments in the NASA Langley HYMETS Facility

    NASA Technical Reports Server (NTRS)

    Splinter, Scott C.; Bey, Kim S.; Gragg, Jeffrey G.; Brewer, Amy

    2011-01-01

    Arc-jet facilities play a major role in the development of heat shield materials for entry vehicles because they are capable of producing representative high-enthalpy flow environments. Arc-jet test data is used to certify material performance for a particular mission and to validate or calibrate models of material response during atmospheric entry. Materials used on missions entering Earth s atmosphere are certified in an arc-jet using a simulated air entry environment. Materials used on missions entering the Martian atmosphere should be certified in an arc-jet using a simulated Martian atmosphere entry environment, which requires the use of carbon dioxide. Carbon dioxide has not been used as a test gas in a United States arc-jet facility since the early 1970 s during the certification of materials for the Viking Missions. Materials certified for the Viking missions have been used on every entry mission to Mars since that time. The use of carbon dioxide as a test gas in an arc-jet is again of interest to the thermal protection system community for certification of new heat shield materials that can increase the landed mass capability for Mars bound missions beyond that of Viking and Pathfinder. This paper describes the modification, operation, and performance of the Hypersonic Materials Environmental Test System (HYMETS) arc-jet facility with carbon dioxide as a test gas. A basic comparison of heat fluxes, various bulk properties, and performance characteristics for various Earth and Martian entry environments in HYMETS is provided. The Earth and Martian entry environments consist of a standard Earth atmosphere, an oxygen-rich Earth atmosphere, and a simulated Martian atmosphere. Finally, a preliminary comparison of the HYMETS arc-jet facility to several European plasma facilities is made to place the HYMETS facility in a more global context of arc-jet testing capability.

  18. The influence of the measurement environment on the accuracy of the extraction of the physical parameters of solar cells

    NASA Astrophysics Data System (ADS)

    Gottschalg, R.; Rommel, M.; Infield, D. G.; Kearney, M. J.

    1999-09-01

    This article concerns the influence of measurement conditions on the extraction of a solar cell's equivalent circuit parameters. Influences previously not investigated are considered, thus helping to define suitable measurement strategies. The influences of measurement environments are investigated, as is the influence of the fitting algorithm chosen. It is shown that the number of measurement points for the current-voltage characteristic can have an important effect on the accuracy of the parameters extracted. The stability of the system is of minor importance, as long as the variations in the measurement conditions are monitored. We also show that the Marquardt-Levenberg algorithm using a least squares error criterion and a hybrid algorithm employing an area criterion outperform other choices of fitting algorithm.

  19. Design and Testing of the Strain Transducer for Measuring Deformations of Pipelines Operating in the Mining-deformable Ground Environment

    NASA Astrophysics Data System (ADS)

    Gawedzki, Waclaw; Tarnowski, Jerzy

    2015-10-01

    Design and laboratory test results of the strain transducer intended for monitoring and assessing stress states of pipelines sited in mining areas are presented in this paper. This transducer allows measuring strains of pipelines subjected to external forces - being the mining operations effect. Pipeline strains can have a direct influence on a tightness loss and penetration of the transported fluid into the environment. The original strain gauge transducer was proposed for performing measurements of strains. It allows measuring circumferential strains and determining the value and direction of the main longitudinal strain. This strain is determined on the basis of measuring component longitudinal strains originating from axial forces and the resultant bending moment. The main purpose of investigations was the experimental verification of the possibility of applying the strain transducer for measuring strains of polyethylene pipelines. The obtained results of the transducer subjected to influences of tensile and compression forces are presented and tests of relaxation properties of polyethylene are performed.

  20. How prior expectations shape multisensory perception.

    PubMed

    Gau, Remi; Noppeney, Uta

    2016-01-01

    The brain generates a representation of our environment by integrating signals from a common source, but segregating signals from different sources. This fMRI study investigated how the brain arbitrates between perceptual integration and segregation based on top-down congruency expectations and bottom-up stimulus-bound congruency cues. Participants were presented audiovisual movies of phonologically congruent, incongruent or McGurk syllables that can be integrated into an illusory percept (e.g. "ti" percept for visual «ki» with auditory /pi/). They reported the syllable they perceived. Critically, we manipulated participants' top-down congruency expectations by presenting McGurk stimuli embedded in blocks of congruent or incongruent syllables. Behaviorally, participants were more likely to fuse audiovisual signals into an illusory McGurk percept in congruent than incongruent contexts. At the neural level, the left inferior frontal sulcus (lIFS) showed increased activations for bottom-up incongruent relative to congruent inputs. Moreover, lIFS activations were increased for physically identical McGurk stimuli, when participants segregated the audiovisual signals and reported their auditory percept. Critically, this activation increase for perceptual segregation was amplified when participants expected audiovisually incongruent signals based on prior sensory experience. Collectively, our results demonstrate that the lIFS combines top-down prior (in)congruency expectations with bottom-up (in)congruency cues to arbitrate between multisensory integration and segregation. PMID:26419391

  1. Implications for space radiation environment models from CREAM & CREDO measurements over half a solar cycle.

    PubMed

    Dyer, C S; Truscott, P R; Peerless, C L; Watson, C J; Evans, H E; Knight, P; Cosby, M; Underwood, C; Cousins, T; Noulty, R; Maag, C

    1999-10-01

    Flight data obtained between 1990 and 1997 from the Cosmic Radiation Environment Monitors CREAM & CREDO carried on UoSAT-3, Space Shuttle, STRV-1a (Space Technology Research Vehicle) and APEX (Advanced Photovoltaic and Electronics Experiment Spacecraft) provide coverage over half a solar cycle. The modulation of cosmic rays and evolution of the South Atlantic Anomaly are observed, the former comprising a factor of three increase at high latitudes and the latter a general increase accompanied by a north-westward drift. Comparison of particle fluxes and linear energy transfer (LET) spectra is made with improved environment & radiation transport calculations which account for shield distributions and secondary particles. While there is an encouraging convergence between predictions and observations, significant improvements are still required, particularly in the treatment of locally produced secondary particles. Solar-particle events during this time period have LET spectra significantly below the October 1989 event which has been proposed as a worst case model. PMID:11542668

  2. Airborne RF Measurement System and Analysis of Representative Flight RF Environment

    NASA Technical Reports Server (NTRS)

    Koppen, Sandra V.; Ely, Jay J.; Smith, Laura J.; Jones, Richard A.; Fleck, Vincent J.; Salud, Maria Theresa; Mielnik, John

    2007-01-01

    Environmental radio frequency (RF) data over a broad band of frequencies were needed to evaluate the airspace around several airports. An RF signal measurement system was designed using a spectrum analyzer connected to an aircraft VHF/UHF navigation antenna installed on a small aircraft. This paper presents an overview of the RF measurement system and provides analysis of a sample of RF signal measurement data over a frequency range of 30 MHz to 1000 MHz.

  3. Ozone measurements in the troposphere of an Amazonian rain forest environment

    NASA Technical Reports Server (NTRS)

    Kirchhoff, V. W. J. H.; Browell, E. V.; Gregory, G. L.

    1988-01-01

    Ozone concentration profiles from the ground to above the stratospheric peak were obtained in an equatorial rain forest environment near Manaus in the Amazon Basin between July and August of 1985. The peak ozone concentration (4.4 x 10 to the 22 molecules/cu cm) was found at 20 mbar (26.6 km). A major pollution (biomass-burning) event which occurred near the end of the experiment was responsible for large changes in ozone concentration.

  4. Diagnostic techniques for measurement of aerodynamic noise in free field and reverberant environment of wind tunnels

    NASA Technical Reports Server (NTRS)

    El-Sum, H. M. A.; Mawardi, O. K.

    1973-01-01

    Techniques for studying aerodynamic noise generating mechanisms without disturbing the flow in a free field, and in the reverberation environment of the ARC wind tunnel were investigated along with the design and testing of an acoustic antenna with an electronic steering control. The acoustic characteristics of turbojet as a noise source, detection of direct sound from a source in a reverberant background, optical diagnostic methods, and the design characteristics of a high directivity acoustic antenna. Recommendations for further studies are included.

  5. Measures of Light in Studies on Light-Driven Plant Plasticity in Artificial Environments

    PubMed Central

    Niinemets, Ülo; Keenan, Trevor F.

    2012-01-01

    Within-canopy variation in light results in profound canopy profiles in foliage structural, chemical, and physiological traits. Studies on within-canopy variations in key foliage traits are often conducted in artificial environments, including growth chambers with only artificial light, and greenhouses with and without supplemental light. Canopy patterns in these systems are considered to be representative to outdoor conditions, but in experiments with artificial and supplemental lighting, the intensity of artificial light strongly deceases with the distance from the light source, and natural light intensity in greenhouses is less than outdoors due to limited transmittance of enclosure walls. The implications of such changes in radiation conditions on canopy patterns of foliage traits have not yet been analyzed. We developed model-based methods for retrospective estimation of distance vs. light intensity relationships, for separation of the share of artificial and natural light in experiments with combined light and for estimation of average enclosure transmittance, and estimated daily integrated light at the time of sampling (Qint,C), at foliage formation (Qint,G), and during foliage lifetime (Qint,av). The implications of artificial light environments were analyzed for altogether 25 studies providing information on within-canopy gradients of key foliage traits for 70 species × treatment combinations. Across the studies with artificial light, Qint,G for leaves formed at different heights in the canopy varied from 1.8- to 6.4-fold due to changing the distance between light source and growing plants. In experiments with combined lighting, the share of natural light at the top of the plants varied threefold, and the share of natural light strongly increased with increasing depth in the canopy. Foliage nitrogen content was most strongly associated with Qint,G, but photosynthetic capacity with Qint,C, emphasizing the importance of explicit description of light

  6. Measures of End-User Information Competency in an Organizational Information Environment

    NASA Astrophysics Data System (ADS)

    Yoon, Chui Young

    Efficient use of information technology (IT) is considered a major determinant of an end-user's business performance and an enterprise's competitiveness. A 16-item tool that can efficiently measure end-user information competency is presented with the measures. The validity and reliability of the tool is confirmed, and the tool's theoretical and practical applications are discussed.

  7. America's Children and the Environment: Measures of Contaminants, Body Burdens, and Illnesses. Second Edition.

    ERIC Educational Resources Information Center

    Woodruff, Tracey J.; Axelrad, Daniel A.; Kyle, Amy D.; Nweke, Onyemaechi; Miller, Gregory G.

    Noting that children may be affected by environmental contaminants in ways quite different from the way adults are affected, this report is the second on trends in measures reflecting environmental factors that may affect the U.S. children's health and well-being. A list of measures and key findings begins the report, followed by five main…

  8. America's Children and the Environment: A First View of Available Measures.

    ERIC Educational Resources Information Center

    Woodruff, Tracey J.; Axelrad, Daniel A.; Kyle, Amy D.

    Noting that children may be affected by environmental contaminants quite differently from the way adults are affected, this report is the first on trends in measures reflecting environmental factors that may affect the health and well-being of children in the United States. For most measures presented, data between 1990 and 1999 were provided by…

  9. High Sensitivity Gravity Measurements in the Adverse Environment of Oil Wells

    NASA Astrophysics Data System (ADS)

    Pfutzner, Harold

    2014-03-01

    Bulk density is a primary measurement within oil and gas reservoirs and is the basis of most reserves calculations by oil companies. The measurement is performed with a gamma-ray source and two scintillation gamma-ray detectors from within newly drilled exploration and production wells. This nuclear density measurement, while very precise is also very shallow and is therefore susceptible to errors due to any alteration of the formation and fluids in the vicinity of the borehole caused by the drilling process. Measuring acceleration due to gravity along a well provides a direct measure of bulk density with a very large depth of investigation that makes it practically immune to errors from near-borehole effects. Advances in gravity sensors and associated mechanics and electronics provide an opportunity for routine borehole gravity measurements with comparable density precision to the nuclear density measurement and with sufficient ruggedness to survive the rough handling and high temperatures experienced in oil well logging. We will describe a borehole gravity meter and its use under very realistic conditions in an oil well in Saudi Arabia. The density measurements will be presented. Alberto Marsala (2), Paul Wanjau (1), Olivier Moyal (1), and Justin Mlcak (1); (1) Schlumberger, (2) Saudi Aramco.

  10. Measurements of Gas and Particle Phase Emissions From Munitions Detonation in a Field Environment

    NASA Astrophysics Data System (ADS)

    Fortner, E. C.; Knighton, W. B.; Timko, M.; Wood, E.; Onasch, T. B.; Kolb, C. E.; Beardsley, H. M.

    2007-12-01

    During the Point of Fire (POF) field campaign conducted at Fort Sill Oklahoma U.S.A. in March 2007 a suite of real- time trace gas and fine (submicron) particulate matter (PM) instrumentation characterized the point of fire emission plumes from large, medium and small caliber weapons systems. Muzzle emission plumes were measured and where appropriate, breach plumes and gun crew breathing zone measurements were also conducted. Aerosol measurements were conducted with an aerosol mass spectrometer (Aerodyne CTOF-AMS) for particle composition, condensation particle counter (CPC) for particle number density and DUSTRAK aerosol monitor for particle mass. Gas phase measurements included CO, CO2, NOx and a variety of trace gas species measured by proton transfer reaction mass spectrometry (PTR-MS) including hydrogen cyanide (HCN), acetonitrile, acrylonitrile, benzene, toluene, benzonitrile and styrene. In the majority of the plume measurements, HCN was the most prominent compound measured by PTR-MS. Quantification of HCN by PTR-MS is difficult due to its proton affinity being close enough to that of water to allow a significant backward reaction of protonated HCN with water, reducing the detection sensitivity and making the response dependent on humidity. We have developed a quantification procedure for HCN based on laboratory measurements of a calibration gas standard of HCN, which allows the humidity dependence to be extracted directly from the proton hydrate ion intensities. The correction factors for HCN are quite significant varying between 10 and 30 depending on sample humidity.

  11. Continuous Quality Measurement: Restructuring Assessment for a New Technological and Organisational Environment.

    ERIC Educational Resources Information Center

    Welsh, John F.; Alexander, Suraj; Dey, Sukhen

    2001-01-01

    Discusses the notion of continuous quality measurement for outcomes assessment in higher education and describes a technology-based continuous quality measurement system (QMS) that has been developed and implemented at the University of Louisville. Discusses the role of QMS in the university's quality improvement scheme and its initial impacts on…

  12. Measuring User Experience of the Student-Centered e-Learning Environment

    ERIC Educational Resources Information Center

    Santoso, Harry B.; Schrepp, Martin; Isal, R. Yugo Kartono; Utomo, Andika Yudha; Priyogi, Bilih

    2016-01-01

    The aim of the current study is to develop an adapted version of User Experience Questionnaire (UEQ) and evaluate a learning management system. Although there is a growing interest on User Experience, there are still limited resources (i.e. measurement tools or questionnaires) available to measure user experience of any products, especially…

  13. Furnace endoscope—measuring fuel spray properties in hot and corrosive environments

    NASA Astrophysics Data System (ADS)

    Miikkulainen, P.; Kankkunen, A.; Järvinen, M. P.

    2004-12-01

    A furnace endoscope was developed to carry out in-furnace measurements of black liquor sprays in order to discover the initial velocity, opening angle and trajectory of the spray, and compare spray disintegration mechanisms and spray appearance with the ones measured in a spray chamber. An error analysis of the velocity measurement method was carried out, and the meaning of the optimum measurement distance from the optics to the observed object is discussed. Some details of the development process of the probe are also presented, especially the definition of the scale of the image and the cooling system of the protection tubes. The furnace endoscope can be used in difficult conditions, such as those found inside a chemical recovery boiler (~1,200°C and corrosive chemicals) with promising and accurate measurement results. The equipment has been tested in several furnaces.

  14. A Fast, Portable, Fiber Optic Spectrofluorometer for Eddy Correlation Flux Measurement in the Aquatic Environment

    NASA Astrophysics Data System (ADS)

    Hu, I. H.; Senft-Grupp, S.; Hemond, H.

    2014-12-01

    The measurement of chemical fluxes between natural waters and their benthic sediments by most existing methods, such as benthic chambers and sediment core incubations, is slow, cumbersome, and often inaccurate. One promising new method for determining benthic fluxes is eddy correlation (EC), a minimally invasive, in situ technique based on high-speed velocity and concentration measurements. Widespread application of EC to a large range of chemicals of interest is currently limited, however, by the availability of rapid, high-resolution chemical sensors capable of precisely measuring concentrations at a point location and at sufficient speed (several Hz). A proof of concept spectrofluorometry instrument has been created that is capable of high-frequency concentration measurements of naturally fluorescent substances. Designed with the EC application in mind, the system utilizes optical fibers to transmit excitation and emission light, enabling in situ measurements at high spatial resolution. Emitted fluorescence light is passed through a tunable monochromator before reaching a photomultiplier tube; photons are quantified by a custom miniaturized, low-power photon counting circuit board. Preliminary results indicate that individual measurements made at 100 Hz of a 10 ppm humic acid solution were precise within 10%, thus yielding a precision of the order of +/- 1% in a second. Used in an EC system, this instrument will enable flux measurements of substances such as naturally occurring fluorescent dissolved organic material (FDOM). Measurement of fluxes of FDOM is significant in its own right, and also will allow the indirect measurement of the numerous other chemical fluxes that are associated with FDOM by using tracer techniques. The use of a tunable monochromator not only allows flexibility in detection wavelength, but also enables full wavelength scans of the emission spectrum, making the spectrofluorometer a dual-function device capable of both characterizing the

  15. Experience with checking potentially contaminated materials released to the environment and testing of the measuring instruments used

    PubMed

    Dryak; Kovar; Suran

    2000-07-01

    Several systems with large area plastic scintillators were tested, which are used to avoid the undesirable and illegal transport of radioactive materials especially at border crossings, in metallurgical works and in plants processing metal scrap, were tested. Measuring equipment with germanium detectors, which is used for check of material released from the Dukovany Nuclear Power Plant, was also tested. The detection possibilities of a chamber with plastic scintillators, for the use during checking of materials released to the environment, were investigated. PMID:10879884

  16. Effect of various environments and computed tomography scanning parameters on renal volume measurements in vitro: A phantom study

    PubMed Central

    Liu, Wangyan; Zhu, Yinsu; Tang, Lijun; Zhu, Xiaomei; Xu, Yi; Yang, Guanyu

    2016-01-01

    Kidney volume is an important parameter in clinical practice, and accurate assessment of kidney volume is vital. The aim of the present study was to evaluate the effect of various environments, tube voltages, tube currents and slice thicknesses on the accuracy of a novel segmentation software in determining renal volume on computed tomography (CT) images. The volumes of potatoes and porcine kidneys were measured on CT images and compared with the actual volumes, which were determined by a water displacement method. CT scans were performed under various situations, including different environments (air or oil); tube voltages/tube currents (80 kVp/200 mAs, 120 kVp/200 mAs, 120 kVp/100 mAs); and reconstructed slice thicknesses (0.75 or 1.5 mm). Percentage errors (PEs) relative to the reference standards were calculated. In addition, attenuation and image noise under different CT scanning parameters were compared. Student's t-test was also used to analyze the effect of various conditions on image quality and volume measurements. The results indicated that the volumes measured in oil were closer to the actual volumes (P<0.05). Furthermore, attenuation and image noise significantly increased when using a tube voltage of 80 kVp, while the mean PEs between 120 and 80 kVp voltages were not significantly different. The mean PEs were greater when using a tube current of 100 mAs compared with a current of 200 mAs (P<0.05). In addition, the volumes measured on 1.5 mm slice thickness were closer to the actual volumes (P<0.05). In conclusion, different environments, tube currents and slice thicknesses may affect the volume measurements. In the present study, the most accurate volume measurements were obtained at 120 kVp/200 mAs and a slice thickness of 1.5 mm. PMID:27446271

  17. Theoretical approach on microscopic bases of stochastic functional self-organization: quantitative measures of the organizational degree of the environment

    NASA Astrophysics Data System (ADS)

    Oprisan, Sorinel Adrian

    2001-11-01

    There has been increased theoretical and experimental research interest in autonomous mobile robots exhibiting cooperative behaviour. This paper provides consistent quantitative measures of organizational degree of a two-dimensional environment. We proved, by the way of numerical simulations, that the theoretically derived values of the feature are reliable measures of aggregation degree. The slope of the feature's dependence on memory radius leads to an optimization criterion for stochastic functional self-organization. We also described the intellectual heritages that have guided our research, as well as possible future developments.

  18. Gender and the environment. Women's time use as a measure of environmental change.

    PubMed

    Awumbila, M; Momsen, J H

    1995-09-01

    These case studies pertain to marginal dry land rural areas in developing countries. The evidence suggests that women have shorter rest periods, greater intensity and fragmentation of work, and greater use of multiple simultaneous occupations than men. Macroeconomic policies have increased the work burden for women and for the poorest populations and have contributed to environmental deterioration. This paper focuses on women's use of time as a factor in explaining women's changing gender role under conditions of environmental stress. The women and the environment debate encompasses two philosophical positions. The ecofeminist theory is that women are one with nature and are unlike men, who manipulate and exploit the environment. The other theory posits that women are managers of the environment and should be approached as separate groups. The developmentalist improves on theory by offering the view that there are differences in resource allocation, entitlements, and responsibilities. The case studies deny that women's roles are fixed and generalized. The case study in Sri Lanka reveals that the Mahaweli irrigation and settlement project brought widespread deforestation and forced women to spend more time and energy in seeking fuel wood. Women adjusted to the changes by reducing the number of trips for wood, increasing the amount of the load, and involving men in the process. The number of families who switched to alternative cooking methods increased. During the dry season more of women's time is spent in washing clothes and cleaning the house. Kitchen gardening is only a wet season activity. A Burkina Faso study found that the average daily hours of work for women was 10.6 in the wet season and 12.4 in the dry season in 1991. In the Caribbean, life revolves around crop and no-crop time. Multiple job holding is a common strategy for small farmers. Gender division of labor and time use are determined by household, local context, family structure, and stage in the

  19. Self-excited coupled cantilevers for mass sensing in viscous measurement environments

    NASA Astrophysics Data System (ADS)

    Yabuno, Hiroshi; Seo, Yasuhiro; Kuroda, Masaharu

    2013-08-01

    The eigenstate shift in two nearly identical and weakly coupled cantilevers provides a means to realize much higher-sensitivity mass detection compared with the eigenfrequency shift approach. We propose using self-excited oscillations for eigenstate detection without using frequency response or resonance curve normally used in conventional methods. Mass sensing thus becomes possible even in high-viscosity environments, where the peak of the frequency response curve is ambiguous or does not exist. The feedback control method is theoretically clarified to produce self-excited oscillation and the validity of the proposed method is investigated experimentally using macroscale coupled cantilevers.

  20. Good places for ageing in place: development of objective built environment measures for investigating links with older people's wellbeing

    PubMed Central

    2011-01-01

    Background There is renewed interest in the role of the built environment in public health. Relatively little research to date investigates its impact on healthy ageing. Ageing in place has been adopted as a key strategy for coping with the challenges of longevity. What is needed is a better understanding of how individual characteristics of older people's residential environments (from front door to wider neighbourhood) contribute to their wellbeing, in order to provide the basis for evidence-based housing/urban design and development of interventions. This research aimed to develop a tool to objectively measure a large range of built environment characteristics, as the basis for a preliminary study of potential relationships with a number of 'place-related' functional, emotional and social wellbeing constructs. Methods Through a review of urban design literature, design documents, and existing measures, a new tool, the NeDeCC (Neighbourhood Design Characteristics Checklist) was developed. It was piloted, refined, and its reliability validated through inter-rater tests. A range of place-related wellbeing constructs were identified and measured through interviews with 200 older people living in a wide variety of rural-urban environments and different types of housing in England. The NeDeCC was used to measure the residential environment of each participant, and significant bivariate relationships with wellbeing variables were identified. Results The NeDeCC was found to have convincing face and construct validity and good inter-rater and test/retest reliability, though it would benefit from use of digital data sources such as Google Earth to eliminate the need for on-site survey. The significant relationships found in the study suggest that there may be characteristics of residential environments of potential relevance for older people's lives that have been overlooked in research to date, and that it may be worthwhile to question some of the assumptions about where

  1. Development of a Harsh Environment Gas Sensor Array for Venus Atmospheric Measurements

    NASA Astrophysics Data System (ADS)

    Makel, D. B.; Carranza, S.

    2015-04-01

    Progress on the development of a compact chemical microsensor array for profiling the chemical composition of the Venus atmosphere and providing gas composition measurements as part of the long lived lander is described.

  2. Quantifying the urban environment: a scale measure of urbanicity outperforms the urban-rural dichotomy

    PubMed Central

    Adair, Linda S

    2007-01-01

    The rapid urbanization of the developing world has important consequences for human health. Although several authorities have called for better research on the relationships between urbanicity and health, most researchers still use a poor measurement of urbanicity, the urban-rural dichotomy. Our goal was to construct a scale of urbanicity using community level data from the Cebu Longitudinal Health and Nutrition Survey. We used established scale development methods to validate the new measure and tested its performance against the dichotomy. The new scale illustrated misclassification by the urban-rural dichotomy, and was able to detect differences in urbanicity, both between communities and across time, that were not apparent before. Furthermore, using a continuous measure of urbanicity allowed for better illustrations of the relationships between urbanicity and health. The new scale is a better measure of urbanicity than the traditionally used urban-rural dichotomy. PMID:17196724

  3. Use of aluminum nitride to obtain temperature measurements in a high temperature and high radiation environment

    DOEpatents

    Wernsman, Bernard R.; Blasi, Raymond J.; Tittman, Bernhard R.; Parks, David A.

    2016-04-26

    An aluminum nitride piezoelectric ultrasonic transducer successfully operates at temperatures of up to 1000.degree. C. and fast (>1 MeV) neutron fluencies of more than 10.sup.18 n/cm.sup.2. The transducer comprises a transparent, nitrogen rich aluminum nitride (AlN) crystal wafer that is coupled to an aluminum cylinder for pulse-echo measurements. The transducer has the capability to measure in situ gamma heating within the core of a nuclear reactor.

  4. Obstacle classification and 3D measurement in unstructured environments based on ToF cameras.

    PubMed

    Yu, Hongshan; Zhu, Jiang; Wang, Yaonan; Jia, Wenyan; Sun, Mingui; Tang, Yandong

    2014-01-01

    Inspired by the human 3D visual perception system, we present an obstacle detection and classification method based on the use of Time-of-Flight (ToF) cameras for robotic navigation in unstructured environments. The ToF camera provides 3D sensing by capturing an image along with per-pixel 3D space information. Based on this valuable feature and human knowledge of navigation, the proposed method first removes irrelevant regions which do not affect robot's movement from the scene. In the second step, regions of interest are detected and clustered as possible obstacles using both 3D information and intensity image obtained by the ToF camera. Consequently, a multiple relevance vector machine (RVM) classifier is designed to classify obstacles into four possible classes based on the terrain traversability and geometrical features of the obstacles. Finally, experimental results in various unstructured environments are presented to verify the robustness and performance of the proposed approach. We have found that, compared with the existing obstacle recognition methods, the new approach is more accurate and efficient. PMID:24945679

  5. Application of the Development in Environment Measurement and Sensibility Nano-Sensing

    NASA Astrophysics Data System (ADS)

    Noda, Kazutoshi; Aizawa, Hidenobu

    Recently, environmental pollution is social problem with nano materials and food contamination is a new social problem. On the other hand, the complaint related to the offensive odor in Japan exceeded 20,000 affairs in 1998, and these problems are not solved. The odor sensing system for detecting and control an offensive odor at an early stage is required. The sensing system using the sense of odor known as one of the fifth senses of human is proposed to these demands. Especially as for e-NOSE system, application will be expected from now on in many fields, such as medical diagnosis, health monitoring, environment, food, robot and a car. The sensing technology in which an electrochemical sensor called quartz crystal microbalance (QCM) is mainly used is making detection mechanisms, such as an electrode and a detection thin film on the nano-level. Therefore, detection films of sensor depend on the characteristic of the sensing devices using on material and processing technology. That the new technology sensor is asked can detect extremely low concentration from ppm to ppb level, and it is the sensor with low influence of environment, such as a gas of the outside for detection, temperature and humidity.

  6. Obstacle Classification and 3D Measurement in Unstructured Environments Based on ToF Cameras

    PubMed Central

    Yu, Hongshan; Zhu, Jiang; Wang, Yaonan; Jia, Wenyan; Sun, Mingui; Tang, Yandong

    2014-01-01

    Inspired by the human 3D visual perception system, we present an obstacle detection and classification method based on the use of Time-of-Flight (ToF) cameras for robotic navigation in unstructured environments. The ToF camera provides 3D sensing by capturing an image along with per-pixel 3D space information. Based on this valuable feature and human knowledge of navigation, the proposed method first removes irrelevant regions which do not affect robot's movement from the scene. In the second step, regions of interest are detected and clustered as possible obstacles using both 3D information and intensity image obtained by the ToF camera. Consequently, a multiple relevance vector machine (RVM) classifier is designed to classify obstacles into four possible classes based on the terrain traversability and geometrical features of the obstacles. Finally, experimental results in various unstructured environments are presented to verify the robustness and performance of the proposed approach. We have found that, compared with the existing obstacle recognition methods, the new approach is more accurate and efficient. PMID:24945679

  7. Surface enhanced Raman spectroscopy measurements of MCF7 cells adhesion in confined micro-environments

    NASA Astrophysics Data System (ADS)

    De Vitis, Stefania; Coluccio, Maria Laura; Gentile, Francesco; Malara, Natalia; Perozziello, Gerardo; Dattola, Elisabetta; Candeloro, Patrizio; Di Fabrizio, Enzo

    2016-01-01

    Undoubtedly cells can perceive the external environment, not only from a biochemical point of view with the related signalling pathways, but also from a physical and topographical perspective. In this sense controlled three dimensional micro-structures as well as patterns at the nano-scale can affect and guide the cell evolution and proliferation, due to the fact that the surrounding environment is no longer isotropic (like the flat surfaces of standard cell culturing) but possesses well defined symmetries and anisotropies. In this work regular arrays of silicon micro-pillars with hexagonal arrangement are used as culturing substrates for MCF-7 breast cancer cells. The characteristic size and spacing of the pillars are tens of microns, comparable with MCF-7 cell dimensions and then well suited to induce acceptable external stimuli. It is shown that these cells strongly modify their morphology for adapting themselves to the micro-structured landscape, by means of protrusions from the main body of the cell. Scanning electron microscopy along with both Raman micro-spectroscopy and surface enhanced Raman spectroscopy are used for topographical and biochemical studies of the new cell arrangement. We have revealed that single MCF-7 cells exploit their capability to produce invadopodia, usually generated to invade the neighboring tissue in metastatic activity, for spanning and growing across separate pillars.

  8. Measurement and interpretation of microbial adenosine tri-phosphate (ATP) in aquatic environments.

    PubMed

    Hammes, Frederik; Goldschmidt, Felix; Vital, Marius; Wang, Yingying; Egli, Thomas

    2010-07-01

    There is a widespread need for cultivation-free methods to quantify viability of natural microbial communities in aquatic environments. Adenosine tri-phosphate (ATP) is the energy currency of all living cells, and therefore a useful indicator of viability. A luminescence-based ATP kit/protocol was optimised in order to detect ATP concentrations as low as 0.0001 nM with a standard deviation of <5%. Using this method, more than 100 water samples from a variety of aquatic environments (drinking water, groundwater, bottled water, river water, lake water and wastewater effluent) were analysed for extracellular ATP and microbial ATP in comparison with flow-cytometric (FCM) parameters. Microbial ATP concentrations ranged between 3% and 97% of total ATP concentrations, and correlated well (R(2)=0.8) with the concentrations of intact microbial cells (after staining with propidium iodide). From this correlation, we calculated an average ATP-per-cell value of 1.75x10(-10)nmol/cell. An even better correlation (R(2)=0.88) was observed between intact biovolume (derived from FCM scatter data) and microbial ATP concentrations, and an average ATP-per-biovolume value of 2.95x10(-9)nmol/microm(3) was calculated. These results support the use of ATP analysis for both routine monitoring and research purposes, and contribute towards a better interpretation of ATP data. PMID:20605621

  9. Motional induction voltage measurements in estuarine environments: the Ria de Aveiro Lagoon (Portugal)

    NASA Astrophysics Data System (ADS)

    Nolasco, Rita; Soares, António; Dias, João M.; Monteiro Santos, Fernando A.; Palshin, N. A.; Represas, Patricia; Vaz, Nuno

    2006-07-01

    Electromagnetic fluctuations in the ocean have external sources like ionospheric-magnetospheric current systems, and purely internal oceanic sources associated with interaction between water velocity fields and the geomagnetic field, that is, the motionally induced voltage (MIV). During the last decade techniques based on MIV have proven to provide reliable information when applied to the flow monitoring at large oceanic channels. In this paper analysis of data resulting from the implementation of these techniques in a small-scale system, that is, the Ria de Aveiro lagoon (Portugal), is presented. A submarine cable crossing the channel at the entrance of the lagoon (Barra channel) allows the measurement of the potential difference between two electrodes located on both sides of the channel. Spectral analysis of these data reveals that measured voltages are dominated by semidiurnal M2, S2/K2 frequencies. Comparison between the sum of the four main constituents determined by harmonic analysis and the sea surface elevation measured at a tide gauge located at the lagoon mouth reveal that the measured potential difference is proportional to the water flow. To estimate the water flow in this location from the MIV measurements the data collected using this methodology were compared with numerical results obtained from a previously calibrated hydrodynamic model. A value of 720 m3 s-1 mV-1 was estimated for the coefficient relating voltage and water transport at Barra. Taking this value into account a sediment layer of about 20 m is estimated, at Barra. The results show that it is possible to indirectly measure the water transport (by tidal and residual flows) through the channel by measuring the differences of electrical potential. This demonstrates the applicability of the MIV method to a small-scale system.

  10. Comparisons of Measurements Made Using Two Sodars in an Urban Environment

    SciTech Connect

    Berg, Larry K.; Reynolds, R. M.; Allwine, K Jerry; Blumberg, Alan

    2006-02-01

    A Scintec MFAS sodar and an AeroVironment Model 3000 Mini-sodar were operated at the Stevens Institute of Technology (SIT) during the Urban Dispersion Program’s New York City field campaign that was conducted between 7 March and 21 March 2005. The Scintec sodar was located on a dock on the Hudson River. The AeroVironment sodar was located on the roof of the Howe Center, a 17-story building located near the Hudson River. The AeroVironment sodar was approximately 90 m above the Scintec, and the horizontal separation of the two units was approximately 350 m. The Scintec MFAS sodar and the AeroVironment mini sodar operate at different frequencies, with the AeroVironment operating at a much higher frequency. Because of these differences, different range gate spacing were selected for each instrument. The range gate spacing used with Scintec MFAS sodar was particularly course to try to probe deeper into the boundary layer. In addition to these two sodars, a meteorological tower was located at the top of the Howe Center. The original experimental plan called for us to operate the Scintec sodar on top the Howe Center, but there was significant ambient noise that degraded the performance. Therefore, the AeroVironment sodar was placed on the building top, while the Scintec MFAS sodar was moved to a dock near the Hudson River. Unfortunately, this location was close to a number of student dormitories, so the sodar could only be operated during Intensive Operations Periods (IOPs). Detailed comparisons of the wind speed and wind direction measured by both sodars and the propeller anemometer have been completed for each IOP. At a height of 100 m above the river (very close to the height of the Howe Center), the wind speed measured by the propeller anemometer and the two sodars were very close. During both IOPs there were times when the wind direction measured by the AeroVironment sodar was much different than the wind direction measured by the Scintec MFAS sodar and the

  11. Development of a Nationally Representative Built Environment Measure of Access to Exercise Opportunities

    PubMed Central

    Roubal, Anne M.; Jovaag, Amanda; Park, Hyojun

    2015-01-01

    We sought to develop a county-level measure to evaluate residents’ access to exercise opportunities. Data were acquired from Esri, DeLorme World Vector (MapMart), and OneSource Global Business Browser (Avention). Using ArcGIS (Esri), we considered census blocks to have access to exercise opportunities if the census block fell within a buffer area around at least 1 park or recreational facility. The percentage of county residents with access to exercise opportunities was reported. Measure validity was examined through correlations with other County Health Rankings & Roadmaps’ measures. Included were 3,114 of 3,141 US counties. The average population with access to exercise opportunities was 52% (range, 0%–100%) with large regional variation. Access to exercise opportunities was most notably associated with no leisure-time physical activity (r = −0.47), premature death (r = −0.38), and obesity (r = −0.36). The measure uses multiple sources to create a valid county-level measure of exercise access. We highlight geographic disparities in access to exercise opportunities and call for improved data. PMID:25611798

  12. Tools for investigating the prior distribution in Bayesian hydrology

    NASA Astrophysics Data System (ADS)

    Tang, Yating; Marshall, Lucy; Sharma, Ashish; Smith, Tyler

    2016-07-01

    Bayesian inference is one of the most popular tools for uncertainty analysis in hydrological modeling. While much emphasis has been placed on the selection of appropriate likelihood functions within Bayesian hydrology, few researchers have evaluated the importance of the prior distribution in deriving appropriate posterior distributions. This paper describes tools for the evaluation of parameter sensitivity to the prior distribution to provide guidelines for defining meaningful priors. The tools described here consist of two measurements, the Kullback-Leibler Divergence (KLD) and the prior information elasticity. The Kullback-Leibler Divergence (KLD) is applied to calculate differences between the prior and posterior distributions for different cases. The prior information elasticity is then used to quantify the responsiveness of the KLD values to the change of prior distributions and length of available data. The tools are demonstrated via a Bayesian framework using an MCMC algorithm for a conceptual hydrologic model with both synthetic and real cases. The results of the application of this toolkit suggest the prior distribution can have a significant impact on the posterior distribution and should be more routinely assessed in hydrologic studies.

  13. Quantitative measurement of radiation pressure on a microcantilever in ambient environment

    SciTech Connect

    Ma, Dakang; Munday, Jeremy N.; Garrett, Joseph L.

    2015-03-02

    Light reflected off a material or absorbed within it exerts radiation pressure through the transfer of momentum. Micro/nano-mechanical transducers have become sensitive enough that radiation pressure can influence these systems. However, photothermal effects often accompany and overwhelm the radiation pressure, complicating its measurement. In this letter, we investigate the radiation force on an uncoated silicon nitride microcantilever in ambient conditions. We identify and separate the radiation pressure and photothermal forces through an analysis of the cantilever's frequency response. Further, by working in a regime where radiation pressure is dominant, we are able to accurately measure the radiation pressure. Experimental results are compared to theory and found to agree within the measured and calculated uncertainties.

  14. Electrochemical noise measurements on carbon and stainless steels in high subcritical and supercritical aqueous environments

    SciTech Connect

    Macdonald, D.D.; Liu, C.; Manahan, M.P. Sr.

    1996-12-31

    The electrochemical noise induced in a pair of corroding carbon steel probes in simulated heat transport circuit fluids of a supercritical fossil-fueled power plant at temperatures up to 550 C and at pressures as high as 276 bar (4,000 psi) was measured as a function of oxygen concentration, flow rate, temperature, and pressure. Additionally, electrochemical noise measurement (ENM) was explored as a means of detecting and monitoring stress corrosion cracking in sensitized Type 304 SS in high-temperature water (up to 288 C). Experimental results from these studies indicate that the electrochemical noise induced from corrosion of steels in high-temperature aqueous systems can be measured in a reproducible manner. The magnitude of the electrochemical noise responds sensibly to changes in the chemical and physical properties of the fluid, and the pattern of the electrochemical noise contains information on the nature of the corrosion processes that occur, including general corrosion, pitting attack, and stress corrosion cracking.

  15. Sound propagation in an urban environment. I: Preliminary analysis of measurements

    NASA Astrophysics Data System (ADS)

    Albert, Donald G.; Liu, Lanbo

    2003-10-01

    Experimental measurements were conducted in a full-scale artificial village to determine the effect of buildings on sound propagation outdoors. The village consisted of 15 concrete block buildings arranged in a 150×150 m area. Explosive charges were detonated to produce acoustic pulses that were digitally recorded by sensors scattered throughout the village. The measurements confirm that diffraction acts as a low pass filter on acoustic waveforms, greatly reducing the peak pressure received by a sensor in the shadow zone. The measured data present clear examples of the effect of reflections on propagation down a street canyon and diffraction around building corners. Complex signatures formed by multiple reflections and diffractions were recorded in situations where the acoustic waves passed multiple buildings in propagating from the source to the receiver. [Work funded by the U.S. Army.

  16. Silver-based electrochemical sensors for sulfide monitoring in deep-sea environments: New approaches based on autonomous measurement

    NASA Astrophysics Data System (ADS)

    Contreira Pereira, Leonardo; Peru, Erwan; Le Bris, Nadine

    2014-05-01

    A large variety of sulfidic environments have been described in the deep-sea since the late seventies, such as hydrothermal vents, cold seeps, organic falls or sub-seafloor microbial habitats. The reactivity of sulfide toward living organisms is a key concern in the exploration and study of these ecosystems, especially at hydrothermal vents where sulfide is a predominant energy source for chemosynthesis. However, the dynamics of sulfide gradients in these marine environments are still poorly documented, constraining the knowledge of their biogeochemical and ecological consequences. In this context, the development of sulfide autonomous sensors became a primary challenge. Measurement tools capable to capture the temporal variability of sulfide concentrations and related parameters are particularly needed, owing to the variability of environments at hydrothermal vents. Silver sulfide potentiometry, which was already applied in situ for punctual measurements, and a new voltammetric method based on bare silver, an electrode material which avoids the need for complex and repeated conditioning of the electrodes, are particularly suitable for unattended use. The advantages and limits of the potentiometric and voltammetric sensing techniques using solid-state electrodes were compared, with respect to the major requirements: concentration ranges; sensitivity to change of pH and temperature; minimum measurement rate; spatial resolution; autonomy; stability and reliability over time. Laboratory tests, combined with unprecedented series of in situ deployments in deep sea and other shallow water sulfidic environments, depict the potential of these tools for monitoring sulfide fluctuations in deep-sea habitats over weeks to months, and their use for investigation of the biogeochemical transformation of sulfur over time. Such sensors, improves the knowledge from these hardly accessible environments and could also reveal usefull to study shallow coastal waters, where sulfidic

  17. Operating in "Strange New Worlds" and Measuring Success - Test and Evaluation in Complex Environments

    NASA Technical Reports Server (NTRS)

    Qualls, Garry; Cross, Charles; Mahlin, Matthew; Montague, Gilbert; Motter, Mark; Neilan, James; Rothhaar, Paul; Tran, Loc; Trujillo, Anna; Allen, B. Danette

    2015-01-01

    Software tools are being developed by the Autonomy Incubator at NASA's Langley Research Center that will provide an integrated and scalable capability to support research and non-research flight operations across several flight domains, including urban and mixed indoor-outdoor operations. These tools incorporate a full range of data products to support mission planning, approval, flight operations, and post-flight review. The system can support a number of different operational scenarios that can incorporate live and archived data streams for UAS operators, airspace regulators, and other important stakeholders. Example use cases are described that illustrate how the tools will benefit a variety of users in nominal and off-nominal operational scenarios. An overview is presented for the current state of the toolset, including a summary of current demonstrations that have been completed. Details of the final, fully operational capability are also presented, including the interfaces that will be supported to ensure compliance with existing and future airspace operations environments.

  18. Thermal effects on human performance in office environment measured by integrating task speed and accuracy.

    PubMed

    Lan, Li; Wargocki, Pawel; Lian, Zhiwei

    2014-05-01

    We have proposed a method in which the speed and accuracy can be integrated into one metric of human performance. This was achieved by designing a performance task in which the subjects receive feedback on their performance by informing them whether they have committed errors, and if did, they can only proceed when the errors are corrected. Traditionally, the tasks are presented without giving this feedback and thus the speed and accuracy are treated separately. The method was examined in a subjective experiment with thermal environment as the prototypical example. During exposure in an office, 12 subjects performed tasks under two thermal conditions (neutral & warm) repeatedly. The tasks were presented with and without feedback on errors committed, as outlined above. The results indicate that there was a greater decrease in task performance due to thermal discomfort when feedback was given, compared to the performance of tasks presented without feedback. PMID:23871091

  19. Configuration management and software measurement in the Ground Systems Development Environment (GSDE)

    NASA Technical Reports Server (NTRS)

    Church, Victor E.; Long, D.; Hartenstein, Ray; Perez-Davila, Alfredo

    1992-01-01

    A set of functional requirements for software configuration management (CM) and metrics reporting for Space Station Freedom ground systems software are described. This report is one of a series from a study of the interfaces among the Ground Systems Development Environment (GSDE), the development systems for the Space Station Training Facility (SSTF) and the Space Station Control Center (SSCC), and the target systems for SSCC and SSTF. The focus is on the CM of the software following delivery to NASA and on the software metrics that relate to the quality and maintainability of the delivered software. The CM and metrics requirements address specific problems that occur in large-scale software development. Mechanisms to assist in the continuing improvement of mission operations software development are described.

  20. Measuring software development characteristics in the local environment. [considering project requirements for spacecraft control

    NASA Technical Reports Server (NTRS)

    Basili, V. R.; Zelkowitz, M. V.

    1978-01-01

    In a brief evaluation of software-related considerations, it is found that suitable approaches for software development depend to a large degree on the characteristics of the particular project involved. An analysis is conducted of development problems in an environment in which ground support software is produced for spacecraft control. The amount of work involved is in the range from 6 to 10 man-years. Attention is given to a general project summary, a programmer/analyst survey, a component summary, a component status report, a resource summary, a change report, a computer program run analysis, aspects of data collection on a smaller scale, progress forecasting, problems of overhead, and error analysis.

  1. The role of metrics and measurements in a software intensive total quality management environment

    NASA Technical Reports Server (NTRS)

    Daniels, Charles B.

    1992-01-01

    Paramax Space Systems began its mission as a member of the Rockwell Space Operations Company (RSOC) team which was the successful bidder on a massive operations consolidation contract for the Mission Operations Directorate (MOD) at JSC. The contract awarded to the team was the Space Transportation System Operations Contract (STSOC). Our initial challenge was to accept responsibility for a very large, highly complex and fragmented collection of software from eleven different contractors and transform it into a coherent, operational baseline. Concurrently, we had to integrate a diverse group of people from eleven different companies into a single, cohesive team. Paramax executives recognized the absolute necessity to develop a business culture based on the concept of employee involvement to execute and improve the complex process of our new environment. Our executives clearly understood that management needed to set the example and lead the way to quality improvement. The total quality management policy and the metrics used in this endeavor are presented.

  2. Identification of boundaries in the cometary environment from AC electric field measurements

    NASA Astrophysics Data System (ADS)

    Mogilevsky, M.; Mikhailov, Y.; Molchanov, O.; Grard, R.; Pedersen, A.; Trotignon, J. G.; Beghin, C.; Formisano, V.; Shapiro, V.; Shevchenko, V.

    1986-12-01

    Electric fields are measured with the AVP-V experiment in the frequency range 8 Hz - 300 kHz. The field amplitude increases significantly, first at a distance of 2×105km, then at distances of 1.2 - 1.5×105km, and 5 - 7×104km from the nucleus. These phenomena have been observed both on VEGA-1 and VEGA-2. The electric field measurements are compared with data obtained from dust and plasma experiments; possible mechanisms responsible for the existence of these boundaries are discussed.

  3. Informational Odds Ratio: A Useful Measure of Epidemiologic Association in Environment Exposure Studies

    PubMed Central

    Efird, Jimmy T.; Lea, Suzanne; Toland, Amanda; Phillips, Christopher J.

    2012-01-01

    The informational odds ratio (IOR) measures the post-exposure odds divided by the pre-exposure odds (ie, information gained after knowing exposure status). A desirable property of an adjusted ratio estimate is collapsibility (ie, the combined crude ratio will not change after adjusting for a variable that is not a confounder). Adjusted traditional odds ratios (TORs) are not collapsible. In contrast, Mantel-Haenszel adjusted IORs generally are collapsible. IORs are a useful measure of disease association in environmental case-referent studies, especially when the disease is common in the exposed and/or unexposed groups. PMID:22518087

  4. Measurement scheme for the Lamb shift in a superconducting circuit with broadband environment

    SciTech Connect

    Gramich, V.; Ankerhold, J.; Solinas, P.; Moettoenen, M.; Pekola, J. P.

    2011-11-15

    Motivated by recent experiments on quantum mechanical charge pumping in a Cooper pair sluice, we present a measurement scheme for observing shifts of transition frequencies in two-level quantum systems induced by broadband environmental fluctuations. In contrast to quantum optical and related setups based on cavities, the impact of a thermal phase reservoir is considered. A thorough analysis of Lamb and Stark shifts within weak-coupling master equations is complemented by nonperturbative results for the model of an exactly solvable harmonic system. The experimental protocol to measure the Lamb shift in experimentally feasible superconducting circuits is analyzed in detail and supported by numerical simulations.

  5. Radionuclides in man and his environment measured by accelerator mass spectrometry

    SciTech Connect

    Hellborg, Ragnar; Erlandsson, Bengt; Kiisk, Madis; Persson, Per; Skog, Goeran; Stenstroem, Kristina; Mattsson, Soeren; Leide-Svegborn, Sigrid; Olofsson, Mikael

    1999-06-10

    Accelerator mass spectrometry (AMS) is a highly sensitive analytical method for measuring very low concentrations of both radionuclides and stable nuclides. For radioanalytical purposes, the main advantages of AMS compared to conventional radiometric methods are the use of smaller samples (mg size) and shorter measuring times (less than one hour). In this report some current applications of the AMS technique at the Lund Pelletron accelerator are presented, in particular studies of {sup 14}C-labeled pharmaceuticals used in clinical nuclear medicine and biomedical research.

  6. Twenty Years of Radiation Measurements in Low-Earth Orbit - What Have We Learned Space Radiation Environment?

    NASA Technical Reports Server (NTRS)

    Golightly, Michael J.; Weyland, Mark D.; Johnson, A. S.; Semones, E.

    2001-01-01

    The advent of the Space Shuttle program has made possible space radiation environment measurements spanning a wide range of altitudes and orbital inclinations over multiple solar cycles. These measurements range from routine integral dose measurements with thermoluminescent dosimeters to particle energy spectra measurements made with a charged particle telescope. This paper will review the new understanding about the space radiation environment gained from this diverse data set. Major findings from these measurements include: estimations of the westward drift rate of the South Atlantic Anomaly (SAA) of 0.28-0.49/y; evidence for a northward component to the SAA drift of 0.08-0.12/y; observation of the formation and decay of the pseudo-stable additional radiation belt following the Mar 1991 SPE and geomagnetic storm with an estimated decay e-folding time of 9-10 months; observation of a local geomagnetic east-west trapped proton exposure anisotropy with an estimated magnitude of 1.6-3.3; demonstration that the trapped proton exposure in low-Earth orbit (LEO) can be reasonably modeled as a power law function of atmospheric density in the SAA region, with best correlations obtained when the exospheric temperature saturates at 938-975 K; the actual solar cycle modulation of trapped proton exposure in LEO is less than predicted by the AP8 model; and the testing and validation of GCR flux models, radiation transport codes, and dynamic geomagnetic cutoff models. Long-term, time-resolved proportional counter measurements made aboard the Mir during the same period provides further demonstration of the solar cycle modulation of the trapped protons at low altitudes - the observed modulation is also well described as power law function of atmospheric density. These data and findings have helped to improve the overall accuracy of pre-mission crew exposure projections using various semi-empirical space environment models, radiation transport codes, and spacecraft radiation

  7. Measuring Sustainability: Deriving Metrics From A Secure Human-Environment Relationship

    EPA Science Inventory

    The ability of individuals and institutions to take actions that would achieve sustainability is often lost in rhetoric about what it is or isn't and how to measure progress. Typically, sustainability is viewed as an objective and in this capacity efforts are made to identify i...

  8. Sensory Processing Measure-HK Chinese Version: Psychometric Properties and Pattern of Response across Environments

    ERIC Educational Resources Information Center

    Lai, Cynthia Y. Y.; Chung, Jenny C. C.; Chan, Chetwyn C. H.; Li-Tsang, Cecilia W. P.

    2011-01-01

    This study aimed to examine the psychometric properties of the Sensory Processing Measure-Hong Kong Chinese version (SPM-HKC), and to study the pattern of behavioral response of children towards sensory events across home and school settings. The two major forms of the SPM, Home Form and Main Classroom Form, were translated into Chinese in this…

  9. MICROCOSM FOR MEASURING SURVIVAL AND CONJUGATION OF GENETICALLY ENGINEERED BACTERIA IN RHIZOSPHERE ENVIRONMENTS

    EPA Science Inventory

    A microcosm is described to evaluate and measure bacterial conjugation in the rhizosphere of barley and radish with strains of Pseudomonas cepacia. he purpose was to describe a standard method useful for evaluating the propensity of genetically engineered microorganisms (GEMs) to...

  10. Measurement and apportionment of radon source terms for modeling indoor environments

    SciTech Connect

    Harley, N.H.

    1992-01-01

    During the present 2 1/2 year contract period, we have made significant Progress in modeling the source apportionment of indoor [sup 222]Rn and in [sup 222]Rn decay product dosimetry. Two additional areas were worked on which we believe are useful for the DOE Radon research Program. One involved an analysis of the research house data, grouping the hourly house [sup 222]Rn measurements into 2 day, 7 day and 90 day intervals to simulate the response of passive monitors. Another area requiring some attention resulted in a publication of 3 years of our indoor/outdoor measurements in a high-rise apartment. Little interest has been evinced in apartment measurements yet 20% of the US population lives in multiple-family dwellings, not in contact with the ground. These data together with a summary of all other published data on apartments showed that apartments have only about 50% greater [sup 222]Rn concentration than the measured outdoor [sup 222]Rn. Apartment dwellers generally represent a low risk group regarding [sup 222]Rn exposure. The following sections describe the main projects in some detail.

  11. Evaluating eddy covariance cotton ET measurements in an advective environment with large weighing lysimeters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eddy covariance (EC) systems are being used to assess the accuracy of remote sensing methods in mapping surface heat fluxes and evapotranspiration from local to regional scales; as well as in crop coefficients development. Therefore, the evaluation of the accuracy of EC heat flux measurements is fu...

  12. High- and low-pressure pneumotachometers measure respiration rates accurately in adverse environments

    NASA Technical Reports Server (NTRS)

    Fagot, R. J.; Mc Donald, R. T.; Roman, J. A.

    1968-01-01

    Respiration-rate transducers in the form of pneumotachometers measure respiration rates of pilots operating high performance research aircraft. In each low pressure or high pressure oxygen system a sensor is placed in series with the pilots oxygen supply line to detect gas flow accompanying respiration.

  13. Conceptualizing and Measuring the Optimal Experience of the eLearning Environment

    ERIC Educational Resources Information Center

    Davis, Robert; Wong, Don

    2007-01-01

    Online learning (eLearning) has become a global phenomenon as many organizations and educational institutions worldwide have entered the field in an attempt to enhance the students' experience of learning. While numerous studies have focused on the effectiveness and benefits of eLearning, few have focused on understanding and measuring the user…

  14. Measuring Transactional Distance in Web-Based Learning Environments: An Initial Instrument Development

    ERIC Educational Resources Information Center

    Huang, Xiaoxia; Chandra, Aruna; DePaolo, Concetta; Cribbs, Jennifer; Simmons, Lakisha

    2015-01-01

    This study was an initial attempt to operationalise Moore's transactional distance theory by developing and validating an instrument measuring the related constructs: dialogue, structure, learner autonomy and transactional distance. Data were collected from 227 online students and analysed through an exploratory factor analysis. Results suggest…

  15. Microwave resonance lamp absorption technique for measuring temperature and OH number density in combustion environments

    NASA Technical Reports Server (NTRS)

    Lempert, Walter R.

    1988-01-01

    A simple technique for simultaneous determination of temperature and OH number density is described, along with characteristic results obtained from measurements using a premixed, hydrogen air flat flame burner. The instrumentation is based upon absorption of resonant radiation from a flowing microwave discharge lamp, and is rugged, relatively inexpensive, and very simple to operate.

  16. Push-pull slab coupled optical sensor for measuring electric fields in a vibrational environment.

    PubMed

    Seng, Frederick; Stan, Nikola; Josephson, Chad; King, Rex; Shumway, LeGrand; Selfridge, Richard; Schultz, Stephen

    2015-06-01

    Vibration-insensitive fiber optic electric field sensor is created by fabricating two sensing elements in close proximity onto the same optical fiber and subtracting the two signals. The device is used to measure an electric field of 10  kV/m, while the sensor is being bent and impacted. PMID:26192684

  17. Recent Advances in the Tempest UAS for In-Situ Measurements in Highly-Dynamic Environments

    NASA Astrophysics Data System (ADS)

    Argrow, B. M.; Frew, E.; Houston, A. L.; Weiss, C.

    2014-12-01

    The spring 2010 deployment of the Tempest UAS during the VORTEX2 field campaign verified that a small UAS, supported by a customized mobile communications, command, and control (C3) architecture, could simultaneously satisfy Federal Aviation Administration (FAA) airspace requirements, and make in-situ thermodynamic measurements in supercell thunderstorms. A multi-hole airdata probe was recently integrated into the Tempest UAS airframe and verification flights were made in spring 2013 to collect in-situ wind measurements behind gust fronts produced by supercell thunderstorms in northeast Colorado. Using instantaneous aircraft attitude estimates from the autopilot, the in-situ measurements were converted to inertial wind estimates, and estimates of uncertainty in the wind measurements was examined. To date, the limited deployments of the Tempest UAS have primarily focused on addressing the engineering and regulatory requirements to conduct supercell research, and the Tempest UAS team of engineers and meteorologists is preparing for deployments with the focus on collecting targeted data for meteorological exploration and hypothesis testing. We describe the recent expansion of the operations area and altitude ceiling of the Tempest UAS, engineering issues for accurate inertial wind estimates, new concepts of operation that include the simultaneous deployment of multiple aircraft with mobile ground stations, and a brief description of our current effort to develop a capability for the Tempest UAS to perform autonomous path planning to maximize energy harvesting from the local wind field for increased endurance.

  18. Built environment attributes related to GPS measured active trips in mid-life and older adults with mobility disabilities

    PubMed Central

    Gell, Nancy M.; Rosenberg, Dori E.; Carlson, Jordan; Kerr, Jacqueline; Belza, Basia

    2015-01-01

    Background Understanding factors which may promote walking in mid-life and older adults with mobility impairments is key given the association between physical activity and positive health outcomes. Objective To examine the relationship between active trips and objective measures of the home neighborhood built environment. Methods Global positioning systems (GPS) data collected on 28 adults age 50+ with mobility disabilities were analyzed for active trips from home. Objective and geographic information systems (GIS) derived measures included Walk Score, population density, street connectivity, crime rates, and slope within the home neighborhood. For this cross-sectional observational study, we conducted mean comparisons between participants who took active trips from home and those who did not for the objective measures. Effect sizes were calculated to assess the magnitude of group differences. Results Nine participants (32%) took active trips from home. Walking in the home neighborhood was significantly associated with GIS derived measures (Walk Score, population density, and street density; effect sizes .9-1.2). Participants who used the home neighborhood for active trips had less slope within 1 km of home but the difference was not significant (73.5 meters±22 vs. 100.8 meters ±38.1, p=.06, d=0.8). There were no statistically significant differences in mean scores for crime rates between those with active trips from home and those without. Conclusions The findings provide preliminary evidence that more walkable environments promote active mobility among mid-life and older adults with mobility disabilities. The data suggest that this population can and does use active transportation modes when the built environment is supportive. PMID:25637503

  19. Measuring leaf chlorophyll concentration from its color: A way in monitoring environment change to plantations

    NASA Astrophysics Data System (ADS)

    Shibghatallah, Muhammad Abdul Hakim; Khotimah, Siti Nurul; Suhandono, Sony; Viridi, Sparisoma; Kesuma, Teja

    2013-09-01

    Leaf colors of a plant can be used to identify stress level due to its adaptation to environmental change. For most leaves green-related colors are sourced from chlorophyll a and b. Chlorophyll concentration is normally measured using a spectrophotometer in laboratory. In some remote observation places, it is impossible to collect the leaves, preserve them, and bring them to laboratory to measure their chlorophyll content. Based on this need, measurement of chlorophyll content is observed through its color. Using CIE chromaticity diagram leaf_color information in RGB is transformed into wavelength (in nm). Paddy seed with variety name IR-64 is used in observation during its vegetation stage t (age of 0-10 days). Light exposure time τ is chosen as environmental change, which normally should be about 12 hours/day, is varied (0-12 hours/day). Each day sample from different exposure time is taken, its color is recorded using HP Deskjet 1050 scanner with 1200 dpi, and its chlorophyll content is obtained from absorption spectrum measured using Campspec M501 Single Beam UV/Vis Spectrophotometer after it is rinsed in 85 % acetone solution and the information from the spectrum is calculated using Arnon method. It has been observed that average wavelength of leaf color λavg is decreased from 570.55 nm to 566.01 nm as is measured for t = 1 - 10 days with τ = 9 hours/day, but chlorophyll concentration C is increased from 0.015 g/l to 3.250 g/l and from 0.000 g/l to 0.774 g/l for chlorophyll a and b, respectively. Other value of τ gives similar results. Based on these results an empirical relation between concentration of chlorophyll a Cc-a and its wavelength λavg can be formulated.

  20. Digital Earth Watch And Picture Post Network: Measuring The Environment Through Digital Images

    NASA Astrophysics Data System (ADS)

    Schloss, A. L.; Beaudry, J.; Carrera, F.; Pickle, J.

    2010-12-01

    Digital Earth Watch (DEW) involves individuals, schools, organizations and communities in a systematic monitoring project of their local environment, especially vegetation health. The program offers people the means to join the Picture Post network and to study and analyze their own findings using DEW software. A Picture Post is an easy-to-use and inexpensive platform for repeatedly taking digital photographs as a standardized set of images of the entire 360 ° landscape, which then can be shared over the Internet on the Picture Post website. This simple concept has the potential to create a wealth of information and data on changing environmental conditions, which is important for a society grappling with the effects of environmental change. Picture Post participants study change over time in their local area, compare digital images with NASA satellite imagery and contribute towards improving their own communities. A key message in DEW is that although plants are dynamic and respond continuously to their environment, they do so either on a time-scale that most people don't notice or with a subtlety our senses can't detect. DEW has created simple tools for monitoring vegetation as a means towards understanding the connection between global climate change and local effects. Picture Posts may be added by anyone interested in monitoring a particular location. The value of a Picture Post is in the commitment of participants to take repeated photographs - monthly, weekly, or even daily - to build up a long-term record over many years. DEW is being developed by a collaborative effort led by the University of New Hampshire with the Federation of Earth Science Information Partners, the University of Southern Maine, and Worcester Polytechnic Institute. This poster will show examples of picture posts and data that can be collected and will describe our soon-to-be-released “ virtual ” picture post cell phone app. The Picture Post network is new and we invite individuals

  1. Transient technique for measuring heat transfer coefficients on stator airfoils in a jet engine environment

    NASA Astrophysics Data System (ADS)

    Gladden, H. J.; Proctor, M. P.

    A transient technique was used to measure heat transfer coefficients on stator airfoils in a high-temperature annular cascade at real engine conditions. The transient response of thin film thermocouples on the airfoil surface to step changes in the gas stream temperature was used to determine these coefficients. In addition, gardon gages and paired thermocouples were also utilized to measure heat flux on the airfoil pressure surface at steady state conditions. The tests were conducted at exit gas stream Reynolds numbers of one-half to 1.9 million based on true chord. The results from the transient technique show good comparison with the steady-state results in both trend and magnitude. In addition, comparison is made with the STAN5 boundary layer code and shows good comparison with the trends. However, the magnitude of the experimental data is consistently higher than the analysis.

  2. Performance measurement of autonomous grasping software in a simulated orbital environment

    NASA Astrophysics Data System (ADS)

    Norsworthy, Robert S.

    1993-12-01

    The EVAHR (extravehicular activity helper/retriever) robot is being developed to perform a variety of navigation and manipulation tasks under astronaut supervision. The EVAHR is equipped with a manipulator and dexterous end-effector for capture and a laser range imager with pan/tilt for target perception. Perception software has been developed to perform target pose estimation, tracking, and motion estimation for rigid, freely rotating, polyhedral objects. Manipulator grasp planning and trajectory control software has also been developed to grasp targets while avoiding collisions. A software simulation of the EVAHR hardware, orbital dynamics, collision detection, and grasp impact dynamics has been developed to test and measure the performance of the integrated software. Performance measurements include grasp success/failure % and time-to-grasp for a variety of targets, initial target states, and simulated pose estimation computing resources.

  3. Cell force measurements in 3D microfabricated environments based on compliant cantilevers.

    PubMed

    Marelli, Mattia; Gadhari, Neha; Boero, Giovanni; Chiquet, Matthias; Brugger, Jürgen

    2014-01-21

    We report the fabrication, functionalization and testing of microdevices for cell culture and cell traction force measurements in three-dimensions (3D). The devices are composed of bent cantilevers patterned with cell-adhesive spots not lying on the same plane, and thus suspending cells in 3D. The cantilevers are soft enough to undergo micrometric deflections when cells pull on them, allowing cell forces to be measured by means of optical microscopy. Since individual cantilevers are mechanically independent of each other, cell traction forces are determined directly from cantilever deflections. This proves the potential of these new devices as a tool for the quantification of cell mechanics in a system with well-defined 3D geometry and mechanical properties. PMID:24217771

  4. Direct measurement of local dissolved oxygen concentration spatial profiles in a cell culture environment.

    PubMed

    Kagawa, Yuki; Matsuura, Katsuhisa; Shimizu, Tatsuya; Tsuneda, Satoshi

    2015-06-01

    Controlling local dissolved oxygen concentration (DO) in media is critical for cell or tissue cultures. Various biomaterials and culture methods have been developed to modulate DO. Direct measurement of local DO in cultures has not been validated as a method to test DO modulation. In the present study we developed a DO measurement system equipped with a Clark-type oxygen microelectrode manipulated with 1 μm precision in three-dimensional space to explore potential applications for tissue engineering. By determining the microelectrode tip position precisely against the bottom plane of culture dishes with rat or human cardiac cells in static monolayer culture, we successfully obtained spatial distributions of DO in the medium. Theoretical quantitative predictions fit the obtained data well. Based on analyses of the variance between samples, we found the data reflected "local" oxygen consumption in the vicinity of the microelectrode and the detection of temporal changes in oxygen consumption rates of cultured cells was limited by the diffusion rate of oxygen in the medium. This oxygen measuring system monitors local oxygen consumption and production with high spatial resolution, and can potentially be used with recently developed oxygen modulating biomaterials to design microenvironments and non-invasively monitor local DO dynamics during culture. PMID:25565074

  5. Experimental measurement of a shipboard fire environment with simulated radioactive materials packages

    SciTech Connect

    Koski, J.A.; Wix, S.D.; Beene, D.E. Jr.

    1996-12-31

    Results from a series of eight test fires ranging in size from 2.2 to 18.8 MW conducted aboard the Coast Guard fire test ship Mayo Lykes at Mobile, Alabama are presented and discussed. Tests aboard the break-bulk type cargo ship consisted of heptane spray fires simulating engine room and galley fires, wood crib fires simulating cargo hold fires, and pool fires staged for comparison to land-based regulatory fire results. Primary instrumentation for the tests consisted of two pipe calorimeters that simulated a typical package shape for radioactive materials packages. The calorimeters were both located adjacent to the fires and on the opposite side of the cargo hold bulkhead nearest the fire. The calorimeters were constructed from 1.5 m length sections of nominal 2 foot diameter schedule 60 steel pipe. Type K thermocouples were attached at 12 locations on the circumference and ends of the calorimeter. Fire heat fluxes to the calorimeter surfaces were estimated with the use of the Sandia SODDIT inverse heat conduction code. Experimental results from all types of tests are discussed, and some comparisons are made between the environments found on the ship and those found in land-based pool fire tests.

  6. Measurement of bottom-reflected sound in bottom-limited propagation environment

    NASA Astrophysics Data System (ADS)

    Hahn, Jooyoung; Park, Joungsoo

    2016-07-01

    To study the bottom reflection of underwater acoustic sound in a bottom-limited propagation environment, an experiment was conducted using four transmitting sounds in the form of a continuous wave from 1 to 6 kHz. The site of the experiment was a continental shelf region off the east coast of Korea where the bottom was composed of sandy mud. The mean water depth was 1100 m in the experiment area. Oceanographic data and acoustic data were collected simultaneously during the experiment. It was found that the sound pressure level decreased by 90 dB to 3.4 km and there is little frequency dependence because a strong direct path contributes more than a bottom-reflected path in sound pressure level. At a range between 6 and 7 km, there is a strong bottom-reflected ray path and frequency dependence exists because the bottom reflection loss varies with frequency at a given grazing angle. Sound pressure levels increase as the range increases between 6 and 7 km by 5.4, 1.9, 1.7, and 1.5 dB at frequencies of 1000, 2490, 3990, and 5490 Hz, respectively.

  7. Source activity correlation effects on LCMV beamformers in a realistic measurement environment.

    PubMed

    Belardinelli, Paolo; Ortiz, Erick; Braun, Christoph

    2012-01-01

    In EEG and MEG studies on brain functional connectivity and source interactions can be performed at sensor or source level. Beamformers are well-established source-localization tools for MEG/EEG signals, being employed in source connectivity studies both in time and frequency domain. However, it has been demonstrated that beamformers suffer from a localization bias due to correlation between source time courses. This phenomenon has been ascertained by means of theoretical proofs and simulations. Nonetheless, the impact of correlated sources on localization outputs with real data has been disputed for a long time. In this paper, by means of a phantom, we address the correlation issue in a realistic MEG environment. Localization performances in the presence of simultaneously active sources are studied as a function of correlation degree and distance between sources. A linear constrained minimum variance (LCMV) beamformer is applied to the oscillating signals generated by the current dipoles within the phantom. Results show that high correlation affects mostly dipoles placed at small distances (1, 5 centimeters). In this case the sources merge. If the dipoles lie 3 centimeters apart, the beamformer localization detects attenuated power amplitudes and blurred sources as the correlation level raises. PMID:22611439

  8. Visual Earth observation performance in the space environment. Human performance measurement 4: Flight experiments

    NASA Technical Reports Server (NTRS)

    Huth, John F.; Whiteley, James D.; Hawker, John E.

    1993-01-01

    A wide variety of secondary payloads have flown on the Space Transportation System (STS) since its first flight in the 1980's. These experiments have typically addressed specific issues unique to the zero-gravity environment. Additionally, the experiments use the experience and skills of the mission and payload specialist crew members to facilitate data collection and ensure successful completion. This paper presents the results of the Terra Scout experiment, which flew aboard STS-44 in November 1991. This unique Earth Observation experiment specifically required a career imagery analyst to operate the Spaceborne Direct-View Optical System (SpaDVOS), a folded optical path telescope system designed to mount inside the shuttle on the overhead aft flight deck windows. Binoculars and a small telescope were used as backup optics. Using his imagery background, coupled with extensive target and equipment training, the payload specialist was tasked with documenting the following: (1) the utility of the equipment; (2) his ability to acquire and track ground targets; (3) the level of detail he could discern; (4) the atmospheric conditions; and (5) other in-situ elements which contributed to or detracted from his ability to analyze targets. Special emphasis was placed on the utility of a manned platform for research and development of future spaceborne sensors. The results and lessons learned from Terra Scout will be addressed including human performance and equipment design issues.

  9. Timepix-based radiation environment monitor measurements aboard the International Space Station

    NASA Astrophysics Data System (ADS)

    Stoffle, Nicholas; Pinsky, Lawrence; Kroupa, Martin; Hoang, Son; Idarraga, John; Amberboy, Clif; Rios, Ryan; Hauss, Jessica; Keller, John; Bahadori, Amir; Semones, Edward; Turecek, Daniel; Jakubek, Jan; Vykydal, Zdenek; Pospisil, Stanislav

    2015-05-01

    A number of small, single element radiation detectors, employing the CERN-based Medipix2 Collaboration's Timepix Application Specific Integrated Circuit (ASIC) coupled to a specially modified version of the USB-Lite interface for that ASIC provided by the Institute for Experimental and Applied Physics (IEAP) at the Czech Technical University in Prague, have been developed at the University of Houston and NASA Johnson Space Center. These detectors, officially designated by NASA as Radiation Environment Monitors (REMs), were deployed aboard the International Space Station in late 2012. Six REM units are currently operating on Station Support Computers (SSCs) and returning data on a daily basis. The associated data acquisition software on the SSCs provides both automated data collection and transfer, as well as algorithms to handle adjustment of acquisition rates and recovery and restart of the acquisition software. A suite of ground software analysis tools has been developed to allow rapid analysis of the data and provides a ROOT-based framework for extending data analysis capabilities.

  10. Measuring accident risk exposure for pedestrians in different micro-environments.

    PubMed

    Lassarre, Sylvain; Papadimitriou, Eleonora; Yannis, George; Golias, John

    2007-11-01

    Pedestrians are mainly exposed to the risk of road accident when crossing a road in urban areas. Traditionally in the road safety field, the risk of accident for pedestrian is estimated as a rate of accident involvement per unit of time spent on the road network. The objective of this research is to develop an approach of accident risk based on the concept of risk exposure used in environmental epidemiology, such as in the case of exposure to pollutants. This type of indicator would be useful for comparing the effects of urban transportation policy scenarios on pedestrian safety. The first step is to create an indicator of pedestrians' exposure, which is based on motorised vehicles' "concentration" by lane and also takes account of traffic speed and time spent to cross. This is applied to two specific micro-environments: junctions and mid-block locations. A model of pedestrians' crossing behaviour along a trip is then developed, based on a hierarchical choice between junctions and mid-block locations and taking account of origin and destination, traffic characteristics and pedestrian facilities. Finally, a complete framework is produced for modelling pedestrians' exposure in the light of their crossing behaviour. The feasibility of this approach is demonstrated on an artificial network and a first set of results is obtained from the validation of the models in observational studies. PMID:17920847

  11. Image-Specific Prior Adaptation for Denoising.

    PubMed

    Lu, Xin; Lin, Zhe; Jin, Hailin; Yang, Jianchao; Wang, James Z

    2015-12-01

    Image priors are essential to many image restoration applications, including denoising, deblurring, and inpainting. Existing methods use either priors from the given image (internal) or priors from a separate collection of images (external). We find through statistical analysis that unifying the internal and external patch priors may yield a better patch prior. We propose a novel prior learning algorithm that combines the strength of both internal and external priors. In particular, we first learn a generic Gaussian mixture model from a collection of training images and then adapt the model to the given image by simultaneously adding additional components and refining the component parameters. We apply this image-specific prior to image denoising. The experimental results show that our approach yields better or competitive denoising results in terms of both the peak signal-to-noise ratio and structural similarity. PMID:26316129

  12. Heated Surface Temperatures Measured by Infrared Detector in a Cascade Environment

    NASA Technical Reports Server (NTRS)

    Boyle, Robert J.

    2002-01-01

    Investigators have used infrared devices to accurately measure heated surface temperatures. Several of these applications have been for turbine heat transfer studies involving film cooling and surface roughness, typically, these measurements use an infrared camera positioned externally to the test section. In cascade studies, where several blades are used to ensure periodic flow, adjacent blades block the externally positioned camera's views of the test blade. To obtain a more complete mapping of the surface temperatures, researchers at the NASA Glenn Research Center fabricated a probe with an infrared detector to sense the blade temperatures. The probe size was kept small to minimize the flow disturbance. By traversing and rotating the probe, using the same approach as for total pressure surveys, one can find the blade surface temperatures. Probe mounted infrared detectors are appropriate for measuring surface temperatures where an externally positioned infrared camera is unable to completely view the test object. This probe consists of a 8-mm gallium arsenide (GaAs) lens mounted in front of a mercury-cadmium-zinc-tellurium (HgCdZnTe) detector. This type of photovoltaic detector was chosen because of its high sensitivity to temperature when the detector is uncooled. The particular application is for relatively low surface temperatures, typically ambient to 100 C. This requires a detector sensitive at long wavelengths. The detector is a commercial product enclosed in a 9-mm-diameter package. The GaAs lens material was chosen because of its glass-like hardness and its good long-wavelength transmission characteristics. When assembled, the 6.4-mm probe stem is held in the traversing actuator. Since the entire probe is above the measurement plane, the flow field disturbance in the measurement plane is minimized. This particular probe body is somewhat wider than necessary, because it was designed to have replaceable detectors and lenses. The signal for the detector is

  13. Simultaneous Measurements of Neutron Environment at Mars from Orbit (Mars Odyssey HEND) and from the Surface (MSL DAN)

    NASA Astrophysics Data System (ADS)

    Martinez Sierra, L. M.; Jun, I.; Litvak, M. L.; Sanin, A. B.; Mitrofanov, I. G.

    2015-12-01

    Currently, the high energy neutron detector (HEND) onboard Mars Odyssey and the dynamic albedo of neutrons (DAN) instrument onboard the Mars Science Laboratory rover are simultaneously measuring the neutron environment from orbit and from the surface, respectively. Naturally-occurring neutrons at Mars are produced from the interactions of galactic cosmic rays (GCR) and solar energetic particles (SEP) with the Martian atmosphere and surface material. The neutron data from these simultaneous orbital and surface measurements are a good indicator for the state of general ambient radiation environments at Mars and can be also used as a means to infer how the ambient radiation is transported through the Martian atmosphere. Both HEND and DAN are healthy, and they provide the unique data sources valuable to study these phenomena for the period since the MSL landing in August 2012. Understanding of why there is correlation or no correlation between the two measurements will provide a key clue to understand the processes of GCR/SEP propagation through the Mars atmosphere and the interaction with the Mars surface materials. More detailed comparison between the two data sets and analysis of HEND/DAN data will be presented in the final presentation. Also, the long-term trend of the HEND/DAN data will be also compared with a general space weather condition. We used only publicly available HEND/DAN data in this study, e.g., open literature and/or planetary data system (PDS).

  14. Measurement result of the neutron monitor onboard Space Environment Data Acquisition Equipment - Attached Payload (SEDA-AP)

    NASA Astrophysics Data System (ADS)

    Koga, K.; Matsumoto, H.; Okudaira, O.; Obara, T.; Yamamoto, T.; Muraki, Y.

    2011-12-01

    To support future space activities, it is very important to acquire the space environmental data which causes the degradation of space parts and spacecraft anomalies. Such data are useful for spacecraft design and manned space activity. Space Environment Data Acquisition - Attached Payload (SEDA-AP) measures the space environment around the International Space Station (ISS) by being attached to the Exposed Facility(EF) of the Japanese Experimental Module ("Kibo"). The Neutron Monitor (NEM) is one of the detectors in SEDA-AP. This instrument was developed to measure the solar neutrons which are produced by solar flare event. The solar neutron is a good indicator to clarify the acceleration mechanism of charged particles at the solar flare. Because of the energy of solar neutron is not influenced by the interplanetary magnetic field, it has the information of the energy of the accelerated charged particle directly. We have been analyzing the neutron data at several M or X class solar flare from September 2009. The mission objectives, instrumentation and measurement status of the neutron monitor are reported.

  15. Microscale Biosensor for Measurement of Volatile Fatty Acids in Anoxic Environments

    PubMed Central

    Meyer, Rikke Louise; Larsen, Lars Hauer; Revsbech, Niels Peter

    2002-01-01

    A microscale biosensor for acetate, propionate, isobutyrate, and lactate is described. The sensor is based on the bacterial respiration of low-molecular-weight, negatively charged species with a concomitant reduction of NO3− to N2O. A culture of denitrifying bacteria deficient in N2O reductase was immobilized in front of the tip of an electrochemical N2O microsensor. The bacteria were separated from the outside environment by an ion-permeable membrane and supplied with nutrients (except for electron donors) from a medium reservoir behind the N2O sensor. The signal of the sensor, which corresponded to the rate of N2O production, was proportional to the supply of the electron donor to the bacterial mass. The selectivity for volatile fatty acids compared to other organic compounds was increased by selectively enhancing the transport of negatively charged compounds into the sensor by electrophoretic migration (electrophoretic sensitivity control). The sensor was susceptible to interference from O2, N2O, NO2−, H2S, and NO3−. Interference from NO3− was low and could be quantified and accounted for. The detection limit was equivalent to about 1 μM acetate, and the 90% response time was 30 to 90 s. The response of the sensor was not affected by changes in pH between 5.5 and 9 and was also unaffected by changes in salinity in the range of 2 to 32‰. The functioning of the sensor over a temperature span of 7 to 30°C was investigated. The concentration range for a linear response was increased five times by increasing the temperature from 7 to 19.5°C. The life span of the biosensor varied between 1 and 3 weeks after manufacturing. PMID:11872469

  16. An integrated probe design for measuring food quality in a microwave environment

    NASA Astrophysics Data System (ADS)

    O'Farrell, M.; Sheridan, C.; Lewis, E.; Zhao, W. Z.; Sun, T.; Grattan, K. T. V.

    2007-07-01

    The work presented describes the development of a novel integrated optical sensor system for the simultaneous and online measurement of the colour and temperature of food as it cooks in a large-scale microwave and hybrid oven systems. The integrated probe contains two different sensor concepts, one to monitor temperature and based on Fibre Bragg Grating (FBG) technology and a second for meat quality, based on reflection spectroscopy in the visible wavelength range. The combination of the two sensors into a single probe requires a careful configuration of the sensor approaches in the creation of an integrated probe design.

  17. Radioactivity measurements in the aquatic environment using in-situ and laboratory gamma-ray spectrometry.

    PubMed

    Eleftheriou, G; Tsabaris, C; Androulakaki, E G; Patiris, D L; Kokkoris, M; Kalfas, C A; Vlastou, R

    2013-12-01

    The in-situ underwater gamma-ray spectrometry method is validated by inter-comparison with laboratory method. Deployments of the spectrometer KATERINA on a submarine spring and laboratory measurements of water samples with HPGe detector were performed. Efficiency calibrations, Monte Carlo simulations and the Minimum Detectable Activity (MDA) estimations were realized. MDAs varied from 0.19 to 10.4 (lab) and 0.05 to 0.35 (in-situ) Bq/L, while activity concentrations differed from 7% (for radon progenies) up to 10% (for (40)K), between the two methods. PMID:24103707

  18. Designing of an online system for radiocaesium measurements in the marine environment.

    PubMed

    Ahmadi, M; Mir Ahmadpour, P; Rabbani, M

    2011-07-01

    An online radiocaesium measuring system (ORMS) is designed to determine the environmental radiocaesium contamination of sea water near the Bushehr Nuclear Power Plant (BNPP). The System consists of a 400-liter, spherical stainless steel water tank, including three aluminum (0.5mm) enclosure NaI (TI) detectors, which each are located in 120° phase angle with size (6×3in.) to confirm each other. Responses of detectors to gamma radiations were calculated, using Monte Carlo code MCNP.4C. Moreover, delay time of each response and the dead time of the whole system to be considered due to designing decisions were calculated. PMID:21388816

  19. Recognition of Prior Vocational Learning in Sweden

    ERIC Educational Resources Information Center

    Andersson, Per; Fejes, Andreas; Ahn, Song-Ee

    2004-01-01

    Initiatives in the recognition of prior learning (RPL) have been taken in Sweden in recent years, mainly focusing on prior vocational learning among immigrants. The government started different projects to find methods for recognising a person's prior learning in the field of vocational competence. This article presents a study of how these…

  20. Prior Learning Assessment Workgroup: 2014 Progress Report

    ERIC Educational Resources Information Center

    West, Jim

    2015-01-01

    Legislation passed in 2011 required the Washington Student Achievement Council (WSAC) to convene a Prior Learning Assessment Workgroup. The workgroup was tasked with coordinating and implementing seven goals, described in statute, to promote the award of college credit for prior learning. Awarding college credit for prior learning increases access…

  1. 19 CFR 162.74 - Prior disclosure.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... loss of revenue finally calculated by CBP shall result in denial of the prior disclosure. (d) Effective... 19 Customs Duties 2 2010-04-01 2010-04-01 false Prior disclosure. 162.74 Section 162.74 Customs... disclosure. (a) In general—(1) A prior disclosure is made if the person concerned discloses the...

  2. 28 CFR 2.58 - Prior orders.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Prior orders. 2.58 Section 2.58 Judicial..., AND JUVENILE DELINQUENTS United States Code Prisoners and Parolees § 2.58 Prior orders. Any order of the United States Board of Parole entered prior to May 14, 1976, including, but not limited to,...

  3. 28 CFR 2.58 - Prior orders.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Prior orders. 2.58 Section 2.58 Judicial..., AND JUVENILE DELINQUENTS United States Code Prisoners and Parolees § 2.58 Prior orders. Any order of the United States Board of Parole entered prior to May 14, 1976, including, but not limited to,...

  4. A system for measuring methane fluxes from inland and coastal wetland environments

    NASA Technical Reports Server (NTRS)

    Sebacher, D. I.; Harriss, R. C.

    1982-01-01

    A CH4 measuring system with a sensitivity of 0.01 ppmv and a response time of 1 sec is described. Pulses are separable from moving and stationary readings, the device floats, and air velocity in the chamber can be controlled in the range 0-4.4 m/sec. The system is set on the water so that controlled speed air from beneath can enter an inner chamber and be pumped through a gas filter correlation system (GFC) before being returned to the chamber. The GFC mechanism yields an absorption signal in the form of a dc voltage, which a processor orders printed on a strip chart as a function of time. Detection of the CH4 amounts is through IR absorption, and the sensitivity of the instrument has been measured at .002-.051 g/sq m per day with air flows in the range 0.90-4.40 m/sec. The unit can be modified to detect CO and CO2, and further applications for low plant canopies and land surfaces are indicated.

  5. PASP Plus: An experiment to measure space-environment effects on photovoltaic power subsystems

    NASA Technical Reports Server (NTRS)

    Guidice, Donald A.

    1992-01-01

    The Photovoltaic Array Space Power Plus Diagnostic experiment (PASP Plus) was accepted as part of the APEX Mission payload aboard a Pegastar satellite to be orbited by a Pegasus launch vehicle in late 1992. The mission's elliptical orbit will allow us to investigate both space plasma and space radiation effects. PASP Plus will have eleven types of solar arrays and a full complement of environmental and interactions diagnostic sensors. Measurements of space-plasma interactions on the various solar arrays will be made at large negative voltages (to investigate arcing parameters) and at large positive voltages (to investigate leakage currents) by biasing the arrays to various levels up to -500 and +500 volts. The long-term deterioration in solar array performance caused by exposure to space radiation will also be investigated; radiation dosage will be measured by an electron/proton dosimeter included in the environmental sensor complement. Experimental results from PASP Plus will help establish cause-and-effect relationships and lead to improved design guidelines and test standards for new-technology solar arrays.

  6. Prediction of Coarse Particle Nitrate From Fine Particle Measurements in a Coastal Environment

    NASA Astrophysics Data System (ADS)

    Campbell, S. W.; Evans, M. C.; Poor, N. D.

    2003-12-01

    Nutrient induced algal growth is one cause of decreased seagrass in the Tampa Bay Estuary. This influx of nutrients arises from the presence of fixed nitrogen in various flows and discharges to the estuary and from atmospheric deposition. One of the goals of BRACE (Bay Regional Atmospheric Chemistry Experiment) is to obtain improved estimates of the atmospheric nitrogen deposition to Tampa Bay. Previous estimates of atmospheric dry deposition of nitrogen to Tampa Bay have been based on Annular Denuder System (ADS) measurements of gaseous nitric acid and ammonia and fine particle (PM2.5) nitrate and ammonium, which extend back to 1996. However, recent coarse particle measurements indicate that, while ammonium primarily exists in fine particles, nitrate is preferentially found in the coarse fraction. The goal of this study is to examine whether the historical data for fine particle nitrate can be used to predict the amount of nitrate in the coarse fraction so as to obtain a more accurate estimate of dry particle deposition of nitrate to the Tampa Bay Estuary. Specifically, it is shown that averaged nitrate distributions obtained from recent micro-orifice impactor data can be used to predict the coarse to fine ratios observed for dichotomous samplers and the fine particle concentrations obtained from the Annular Denuder System. This provides some confidence that the impactor results may be used in conjunction with earlier fine particle data to obtain an estimate of coarse particle nitrate concentrations, and therefore an improved estimate of nitrate flux to the estuary.

  7. Towards an automatic early stress recognition system for office environments based on multimodal measurements: A review.

    PubMed

    Alberdi, Ane; Aztiria, Asier; Basarab, Adrian

    2016-02-01

    Stress is a major problem of our society, as it is the cause of many health problems and huge economic losses in companies. Continuous high mental workloads and non-stop technological development, which leads to constant change and need for adaptation, makes the problem increasingly serious for office workers. To prevent stress from becoming chronic and provoking irreversible damages, it is necessary to detect it in its early stages. Unfortunately, an automatic, continuous and unobtrusive early stress detection method does not exist yet. The multimodal nature of stress and the research conducted in this area suggest that the developed method will depend on several modalities. Thus, this work reviews and brings together the recent works carried out in the automatic stress detection looking over the measurements executed along the three main modalities, namely, psychological, physiological and behavioural modalities, along with contextual measurements, in order to give hints about the most appropriate techniques to be used and thereby, to facilitate the development of such a holistic system. PMID:26621099

  8. A system for measuring bottom profile, waves and currents in the high-energy nearshore environment

    USGS Publications Warehouse

    Sallenger, A.H., Jr.; Howard, P.C.; Fletcher, C. H., III; Howd, P.A.

    1983-01-01

    A new data-acquisition system capable of measuring waves, currents and the nearshore profile in breaking waves as high as 5 m has been developed and successfully field-tested. Components of the mechanical system are a sled carrying a vertical mast, a double-drum winch placed landward of the beach, and a line that runs from one drum of the winch around three blocks, which are the corners of a right triangle, to the other drum of the winch. The sled is attached to the shore-normal side of the triangular line arrangement and is pulled offshore by one drum of the winch and onshore by the other. The profile is measured as the sled is towed along the shore-normal transect using an infrared rangefinder mounted landward of the winch and optical prisms mounted on top of the sled's mast. A pressure sensor and two-axis electromagnetic current meter are mounted on the frame of the sled. These data are encoded on the sled and telemetered to a receiving/recording station onshore. Preliminary results suggest that near-bottom offshore-flowing currents during periods of high-energy swell are important in forcing changes to the configuration of the nearshore profile. ?? 1983.

  9. Optical techniques for sensing and measurement in hostile environments; Proceedings of the Meeting, Orlando, FL, May 21, 22, 1987

    SciTech Connect

    Gillespie, C.H.; Greenwell, R.A.

    1987-01-01

    Papers are presented on referencing in fiber optic sensing systems, optical fiber chemical sensing networks, and the radiation response of new pure silica fibers. Also considered are a comparison of gamma, neutron, and proton irradiations of multimode fibers, a pinhole camera for hot environment viewing of electron beam materials processing, and the utilization of optical image data from the advanced test accelerator. Other topics include the application of an interferometer spectrometer aboard the Space Shuttle with a payload specialist in the control loop, hydrogen chloride measurements in launch-vehicle exhaust clouds, and a rocket-borne telescoped Fourier transform spectrometer operating at 10 K.

  10. Testing the Assumption of Cross-Level Measurement Invariance in Multilevel Models: Evidence from School and Classroom Environment Surveys. CRESST Report 829

    ERIC Educational Resources Information Center

    Schweig, Jonathan

    2013-01-01

    Measures of classroom and school environments are a central component of policy efforts that assess school and teacher quality. These measures are often formed by aggregating individual survey responses to form group-level measures, and assume an invariant measurement model holds at both the individual and group level. This paper explores the…

  11. NASA's MEaSUREs Program: Making Earth System data records for Use in Research Environments

    NASA Astrophysics Data System (ADS)

    Maiden, M. E.; Ramapriyan, H. K.

    2008-12-01

    A major need stated by the NASA Earth science research strategy is to develop long-term, consistent, and calibrated data and products that are valid across multiple missions and satellite sensors. NASA coined the term Earth System Data Record, or ESDR, and defined the term to mean a unified and coherent set of observations of a given parameter of the Earth system, which is optimized to meet specific requirements in addressing science questions. For creating these basic records, a science measurement focus brings together expertise in multiple instrument characterization and calibration, data processing, science-based product generation and distribution, science tools, and interactive relationships with the broader science community. There is a sense that these important records must have a maturity that includes vetting within the community that utilizes them. Responsible NASA Managers ensure that each Project seeks guidance from community scrutiny and review of product quality and acceptability. MEaSUREs Projects have requirements to make data available on a nonexclusive basis. For example, each Project must maintain a public WWW-compliant presence and plan on transferring the final version of the data products to a NASA-designated Data Center. Principal Investigators for these Projects enter into Cooperative Agreements (instead of Grants) with NASA. Nominally, an alternate Data Rights section in these Agreements codifies an agreement that the input data, the scientific software used for processing the raw instrument data into scientific data, including source code, and the ESDRs with accompanying metadata and quality assessments, is exchanged without restriction as to its disclosure, use, or duplication. For these important records, complete scientific validation must be enabled and full utilization encouraged. The first request for proposals under the MEaSUREs Program was sent out by NASA in late 2006 and resulted in the selection of 29 projects covering

  12. Number size distribution measurements of biological aerosols under contrasting environments and seasons from southern tropical India

    NASA Astrophysics Data System (ADS)

    Valsan, Aswathy; Cv, Biju; Krishna, Ravi; Huffman, Alex; Poschl, Ulrich; Gunthe, Sachin

    2016-04-01

    Biological aerosols constitute a wide range of dead and alive biological materials and structures that are suspended in the atmosphere. They play an important role in the atmospheric physical, chemical and biological processes and health of living being by spread of diseases among humans, plants, and, animals. The atmospheric abundance, sources, physical properties of PBAPs as compared to non-biological aerosols, however, is poorly characterized. Though omnipresent, their concentration and composition exhibit large spatial and temporal variations depending up on their sources, land-use, and local meteorology. The Indian tropical region, which constitutes approximately 18% of the world's total population exhibits vast geographical extend and experiences a distinctive meteorological phenomenon by means of Indian Summer Monsoon (IMS). Thus, the sources, properties and characteristics of biological aerosols are also expected to have significant variations over the Indian subcontinent depending upon the location and seasons. Here we present the number concentration and size distribution of Fluorescent Biological Aerosol Particles (FBAP) from two contrasting locations in Southern tropical India measured during contrasting seasons using Ultra Violet Aerodynamic Particle Sizer (UV-APS). Measurements were carried out at a pristine high altitude continental site, Munnar (10.09 N, 77.06 E; 1605 m asl) during two contrasting seasons, South-West Monsoon (June-August, 2014) and winter (Jan - Feb, 2015) and in Chennai, a coastal urban area, during July - November 2015. FBAP concentrations at both the locations showed large variability with higher concentrations occurring at Chennai. Apart from regional variations, the FBAP concentrations also exhibited variations over two different seasons under the same environmental condition. In Munnar the FBAP concentration increased by a factor of four from South-West Monsoon to winter season. The average size distribution of FBAP at both

  13. Insulator-protected mechanically controlled break junctions for measuring single-molecule conductance in aqueous environments

    NASA Astrophysics Data System (ADS)

    Muthusubramanian, N.; Galan, E.; Maity, C.; Eelkema, R.; Grozema, F. C.; van der Zant, H. S. J.

    2016-07-01

    We present a method to fabricate insulated gold mechanically controlled break junctions (MCBJ) by coating the metal with a thin layer of aluminum oxide using plasma enhanced atomic layer deposition. The Al2O3 thickness deposited on the MCBJ devices was varied from 2 to 15 nm to test the suppression of leakage currents in deionized water and phosphate buffered saline. Junctions coated with a 15 nm thick oxide layer yielded atomically sharp electrodes and negligible conductance counts in the range of 1 to 10-4 G0 (1 G0 = 77 μS), where single-molecule conductances are commonly observed. The insulated devices were used to measure the conductance of an amphiphilic oligophenylene ethynylene derivative in deionized water.

  14. Wind field measurements for the mitigation of airborne health threats in a complex urban environment

    NASA Astrophysics Data System (ADS)

    Arend, Mark; Santoro, David; Abdelazim, Sameh; Moshary, Fred; Ahmed, Sam

    2009-05-01

    The Department of Homeland Security (DHS) sponsored Urban Dispersion Program (UDP) resulted in the strategic placement of weather instruments in New York City (NYC) and the transition of some instruments to the City College of New York (CCNY) operated NYC MetNet to provide timely and accurate information on "skimming field" winds above city building tops. In order to extend the observational capabilities of the NYC MetNet, a cost effective portable eye safe fiber optic based coherent wind lidar system is currently under development in CCNY laboratories. Wind lidar measurements, coupled with the continuous observations from the NYC MetNet, should support the initialization, feedback and development of plume models that would be used after an initial detection of airborne toxins. An overview of the lidar system design and the NYC MetNet will be given.

  15. Sequential quantum secret sharing in a noisy environment aided with weak measurements

    NASA Astrophysics Data System (ADS)

    Ray, Maharshi; Chatterjee, Sourav; Chakrabarty, Indranil

    2016-05-01

    In this work we give a (n,n)-threshold protocol for sequential secret sharing of quantum information for the first time. By sequential secret sharing we refer to a situation where the dealer is not having all the secrets at the same time, at the beginning of the protocol; however if the dealer wishes to share secrets at subsequent phases she/he can realize it with the help of our protocol. First of all we present our protocol for three parties and later we generalize it for the situation where we have more (n> 3) parties. Interestingly, we show that our protocol of sequential secret sharing requires less amount of quantum as well as classical resource as compared to the situation wherein existing protocols are repeatedly used. Further in a much more realistic situation, we consider the sharing of qubits through two kinds of noisy channels, namely the phase damping channel (PDC) and the amplitude damping channel (ADC). When we carry out the sequential secret sharing in the presence of noise we observe that the fidelity of secret sharing at the kth iteration is independent of the effect of noise at the (k - 1)th iteration. In case of ADC we have seen that the average fidelity of secret sharing drops down to ½ which is equivalent to a random guess of the quantum secret. Interestingly, we find that by applying weak measurements one can enhance the average fidelity. This increase of the average fidelity can be achieved with certain trade off with the success probability of the weak measurements.

  16. Complex role of secondary electron emissions in dust grain charging in space environments: measurements on Apollo 11 & 17 dust grains

    NASA Astrophysics Data System (ADS)

    Abbas, Mian; Tankosic, Dragana; Spann, James; Leclair, Andre C.

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, by electron/ion collisions, and sec-ondary electron emissions. Knowledge of the dust grain charges and equilibrium potentials is important for understanding of a variety of physical and dynamical processes in the interstel-lar medium (ISM), and heliospheric, interplanetary, planetary, and lunar environments. The high vacuum environment on the lunar surface leads to some unusual physical and dynam-ical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. It has been well recognized that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the corresponding values for bulk materials and theoretical models. In this paper we present experimental results on charging of individual dust grains selected from Apollo 11 and Apollo 17 dust samples by exposing them to mono-energetic electron beams in the 10-400 eV energy range. The charging rates of positively and negatively charged particles of 0.2 to 13 µm diam-eters are discussed in terms of the secondary electron emission (SEE) process, which is found to be a complex charging process at electron energies as low as 10-25 eV, with strong parti-cle size dependence. The measurements indicate substantial differences between dust charging properties of individual small size dust grains and of bulk materials.

  17. Minimally Informative Prior Distributions for PSA

    SciTech Connect

    Dana L. Kelly; Robert W. Youngblood; Kurt G. Vedros

    2010-06-01

    A salient feature of Bayesian inference is its ability to incorporate information from a variety of sources into the inference model, via the prior distribution (hereafter simply “the prior”). However, over-reliance on old information can lead to priors that dominate new data. Some analysts seek to avoid this by trying to work with a minimally informative prior distribution. Another reason for choosing a minimally informative prior is to avoid the often-voiced criticism of subjectivity in the choice of prior. Minimally informative priors fall into two broad classes: 1) so-called noninformative priors, which attempt to be completely objective, in that the posterior distribution is determined as completely as possible by the observed data, the most well known example in this class being the Jeffreys prior, and 2) priors that are diffuse over the region where the likelihood function is nonnegligible, but that incorporate some information about the parameters being estimated, such as a mean value. In this paper, we compare four approaches in the second class, with respect to their practical implications for Bayesian inference in Probabilistic Safety Assessment (PSA). The most commonly used such prior, the so-called constrained noninformative prior, is a special case of the maximum entropy prior. This is formulated as a conjugate distribution for the most commonly encountered aleatory models in PSA, and is correspondingly mathematically convenient; however, it has a relatively light tail and this can cause the posterior mean to be overly influenced by the prior in updates with sparse data. A more informative prior that is capable, in principle, of dealing more effectively with sparse data is a mixture of conjugate priors. A particular diffuse nonconjugate prior, the logistic-normal, is shown to behave similarly for some purposes. Finally, we review the so-called robust prior. Rather than relying on the mathematical abstraction of entropy, as does the constrained

  18. Effect of magnetic field fluctuation on ultra-low field MRI measurements in the unshielded laboratory environment

    NASA Astrophysics Data System (ADS)

    Liu, Chao; Chang, Baolin; Qiu, Longqing; Dong, Hui; Qiu, Yang; Zhang, Yi; Krause, Hans-Joachim; Offenhäusser, Andreas; Xie, Xiaoming

    2015-08-01

    Magnetic field fluctuations in our unshielded urban laboratory can reach hundreds of nT in the noisy daytime and is only a few nT in the quiet midnight. The field fluctuation causes the Larmor frequency fL to drift randomly for several Hz during the unshielded ultra-low field (ULF) nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) measurements, thus seriously spoiling the averaging effect and causing imaging artifacts. By using an active compensation (AC) technique based on the spatial correlation of the low-frequency magnetic field fluctuation, the field fluctuation can be suppressed to tens of nT, which is a moderate situation between the noisy daytime and the quiet midnight. In this paper, the effect of the field fluctuation on ULF MRI measurements was investigated. The 1D and 2D MRI signals of a water phantom were measured using a second-order low-Tc superconducting quantum interference device (SQUID) in three fluctuation cases: severe fluctuation (noisy daytime), moderate fluctuation (daytime with AC) and minute fluctuation (quiet midnight) when different gradient fields were applied. When the active compensation is applied or when the frequency encoding gradient field Gx reaches a sufficiently strong value in our measurements, the image artifacts become invisible in all three fluctuation cases. Therefore it is feasible to perform ULF-MRI measurements in unshielded urban environment without imaging artifacts originating from magnetic fluctuations by using the active compensation technique and/or strong gradient fields.

  19. Effect of magnetic field fluctuation on ultra-low field MRI measurements in the unshielded laboratory environment.

    PubMed

    Liu, Chao; Chang, Baolin; Qiu, Longqing; Dong, Hui; Qiu, Yang; Zhang, Yi; Krause, Hans-Joachim; Offenhäusser, Andreas; Xie, Xiaoming

    2015-08-01

    Magnetic field fluctuations in our unshielded urban laboratory can reach hundreds of nT in the noisy daytime and is only a few nT in the quiet midnight. The field fluctuation causes the Larmor frequency fL to drift randomly for several Hz during the unshielded ultra-low field (ULF) nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) measurements, thus seriously spoiling the averaging effect and causing imaging artifacts. By using an active compensation (AC) technique based on the spatial correlation of the low-frequency magnetic field fluctuation, the field fluctuation can be suppressed to tens of nT, which is a moderate situation between the noisy daytime and the quiet midnight. In this paper, the effect of the field fluctuation on ULF MRI measurements was investigated. The 1D and 2D MRI signals of a water phantom were measured using a second-order low-Tc superconducting quantum interference device (SQUID) in three fluctuation cases: severe fluctuation (noisy daytime), moderate fluctuation (daytime with AC) and minute fluctuation (quiet midnight) when different gradient fields were applied. When the active compensation is applied or when the frequency encoding gradient field Gx reaches a sufficiently strong value in our measurements, the image artifacts become invisible in all three fluctuation cases. Therefore it is feasible to perform ULF-MRI measurements in unshielded urban environment without imaging artifacts originating from magnetic fluctuations by using the active compensation technique and/or strong gradient fields. PMID:26037135

  20. Improving measurement of forest light environments with hemispherical photography: the use of non-RGB color spaces

    NASA Astrophysics Data System (ADS)

    Prohaska, N.; Wu, J.; Stark, S. C.; Albert, L.; Smith, M.; Taylor, T.; Wiedemann, K.; da Silva, R.; Saleska, S. R.

    2013-12-01

    Light environments are fundamental determinants of leaf growth and function within forest canopies, and improved methods to quickly and easily measure light micro-environments can contribute to our ability to understand how light drives ecosystem processes. Upward facing hemispherical photographs are a common tool for quantifying the light environment of forest canopies, by classifying the photo (image segmentation) into ';sky' and ';not-sky' regions. However, accurate image segmentation of hemispherical photos into ';sky' and ';not sky' is difficult except under uniform diffuse light, which occurs only rarely (e.g. at dawn, dusk, or with uniform cloud conditions). This constraint on image acquisition greatly reduces the ability to obtain data in the field. Here, we develop and assess a new approach to using hemispherical image data acquired under non-ideal conditions in a broadleaf evergreen tropical forest in the Amazon of Brazil. Unlike one common approach that uses blue channel data only, we use information from all three channels by mathematically transforming images into other 3-channel color spaces. We compared results of image segmentation into sky and not-sky canopy regions across 14 non-RGB color spaces as well as the original RGB color space, as derived from 15 digital photos acquired at various positions within the forest canopy. Images were selected for variation in presence and absence of bright sun, overexposed leaves, specular highlights, blue-sky, and not-blue sky. We applied two widely used techniques (interactive thresholding and 2-dimensional maximum entropy) to classify the single-channel image from each color space into sky and not-sky regions for all photos. We assessed classification accuracy with confusion matrices that compared the automatic classifications to a user-defined ';true' classification. We found that the 14 non-RGB color spaces included four independent channels that were consistently superior to RGB channels in their

  1. Measuring and managing the work environment of the mid-level provider – the neglected human resource

    PubMed Central

    McAuliffe, Eilish; Bowie, Cameron; Manafa, Ogenna; Maseko, Fresier; MacLachlan, Malcolm; Hevey, David; Normand, Charles; Chirwa, Maureen

    2009-01-01

    Background Much has been written in the past decade about the health workforce crisis that is crippling health service delivery in many middle-income and low-income countries. Countries having lost most of their highly qualified health care professionals to migration increasingly rely on mid-level providers as the mainstay for health services delivery. Mid-level providers are health workers who perform tasks conventionally associated with more highly trained and internationally mobile workers. Their training usually has lower entry requirements and is for shorter periods (usually two to four years). Our study aimed to explore a neglected but crucial aspect of human resources for health in Africa: the provision of a work environment that will promote motivation and performance of mid-level providers. This paper explores the work environment of mid-level providers in Malawi, and contributes to the validation of an instrument to measure the work environment of mid-level providers in low-income countries. Methods Three districts were purposively sampled from each of the three geographical regions in Malawi. A total of 34 health facilities from the three districts were included in the study. All staff in each of the facilities were included in the sampling frame. A total of 153 staff members consented to be interviewed. Participants completed measures of perceptions of work environment, burnout and job satisfaction. Findings The Healthcare Provider Work Index, derived through Principal Components Analysis and Rasch Analysis of our modification of an existing questionnaire, constituted four subscales, measuring: (1) levels of staffing and resources; (2) management support; (3) workplace relationships; and (4) control over practice. Multivariate analysis indicated that scores on the Work Index significantly predicted key variables concerning motivation and attrition such as emotional exhaustion, job satisfaction, satisfaction with the profession and plans to leave the

  2. Leak rate measurements for satellite subsystems and residual gas analysis during space environment tests. [thermal vacuum and solar simulation tests

    NASA Technical Reports Server (NTRS)

    Nuss, H. E.

    1975-01-01

    The measuring and evaluation procedure for the determination of leak rates of satellite subsystems with a quadrupole mass spectrometer, and the results of the residual gas analysis are described. The method selected for leak rate determination was placing the system into a vacuum chamber and furnishing the chamber with a mass spectrometer and calibrated leaks. The residual gas of a thermal vacuum test facility, in which the thermal balance test radiation input was simulated by a heated canister, was analyzed with the mass spectrometer in the atomic mass unit range up to 300 amu. In addition to the measurements during the space environment tests, mass spectrometric studies were performed with samples of spacecraft materials. The studies were carried out during tests for the projects HELIOS, AEROS B and SYMPHONIE.

  3. The power prior: theory and applications.

    PubMed

    Ibrahim, Joseph G; Chen, Ming-Hui; Gwon, Yeongjin; Chen, Fang

    2015-12-10

    The power prior has been widely used in many applications covering a large number of disciplines. The power prior is intended to be an informative prior constructed from historical data. It has been used in clinical trials, genetics, health care, psychology, environmental health, engineering, economics, and business. It has also been applied for a wide variety of models and settings, both in the experimental design and analysis contexts. In this review article, we give an A-to-Z exposition of the power prior and its applications to date. We review its theoretical properties, variations in its formulation, statistical contexts for which it has been used, applications, and its advantages over other informative priors. We review models for which it has been used, including generalized linear models, survival models, and random effects models. Statistical areas where the power prior has been used include model selection, experimental design, hierarchical modeling, and conjugate priors. Frequentist properties of power priors in posterior inference are established, and a simulation study is conducted to further examine the empirical performance of the posterior estimates with power priors. Real data analyses are given illustrating the power prior as well as the use of the power prior in the Bayesian design of clinical trials. PMID:26346180

  4. A Radio-Polarisation and Rotation Measure Study of the Gum Nebula and Its Environment

    NASA Astrophysics Data System (ADS)

    Purcell, C. R.; Gaensler, B. M.; Sun, X. H.; Carretti, E.; Bernardi, G.; Haverkorn, M.; Kesteven, M. J.; Poppi, S.; Schnitzeler, D. H. F. M.; Staveley-Smith, L.

    2015-05-01

    The Gum Nebula is 36°-wide shell-like emission nebula at a distance of only ˜450 pc. It has been hypothesized to be an old supernova remnant, fossil H ii region, wind-blown bubble, or combination of multiple objects. Here we investigate the magneto-ionic properties of the nebula using data from recent surveys: radio-continuum data from the NRAO VLA and S-band Parkes All Sky Surveys, and H α data from the Southern H-Alpha Sky Survey Atlas. We model the upper part of the nebula as a spherical shell of ionized gas expanding into the ambient medium. We perform a maximum-likelihood Markov chain Monte Carlo fit to the NVSS rotation measure data, using the H α data to constrain average electron density in the shell ne. Assuming a latitudinal background gradient in rotation measure, we find {{n}e}=1.3-0.4+0.4 c{{m}-3}, angular radius {{φ }outer}=22\\buildrel{\\circ}\\over{.} 7-0.1+0.1, shell thickness dr=18.5-1.4+1.5 pc, ambient magnetic field strength {{B}0}=3.9-2.2+4.9 μ G, and warm gas filling factor f=0.3-0.1+0.3. We constrain the local, small-scale (˜260 pc) pitch-angle of the ordered Galactic magnetic field to +7{}^\\circ ≲ \\wp ≲ +44{}^\\circ , which represents a significant deviation from the median field orientation on kiloparsec scales (˜-7.°2). The moderate compression factor X=6.0-2.5+5.1 at the edge of the H α shell implies that the “old supernova remnant” origin is unlikely. Our results support a model of the nebula as a H ii region around a wind-blown bubble. Analysis of depolarization in 2.3 GHz S-PASS data is consistent with this hypothesis and our best-fitting values agree well with previous studies of interstellar bubbles.

  5. Potential for Measurement of Trace Volatile Organic Compounds in Closed Environments Using Gas Chromatograph/Differential Mobility Spectrometer

    NASA Technical Reports Server (NTRS)

    Limero, Thomas; Cheng, Patti

    2007-01-01

    For nearly 3.5 years, the Volatile Organic Analyzer (VOA) has routinely analyzed the International Space Station (ISS) atmosphere for a target list of approximately 20 volatile organic compounds (VOCs). Additionally, an early prototype of the VOA collected data aboard submarines in two separate trials. Comparison of the data collected on ISS and submarines showed a surprising similarity in the atmospheres of the two environments. Furthermore, in both cases it was demonstrated that the VOA data can detect hardware issues unrelated to crew health. Finally, it was also clear in both operations that the VOA s size and resource consumption were major disadvantages that would restrict its use in the future. The VOA showed the value of measuring VOCs in closed environments, but it had to be shrunk if it was to be considered for future operations in these environments that are characterized by cramped spaces and limited resources. The Sionex Microanalyzer is a fraction of the VOA s size and this instrument seems capable of maintaining or improving upon the analytical performance of the VOA. The two design improvements that led to a smaller, less complex instrument are the Microanalyzer s use of recirculated air as the gas chromatograph s carrier gas and a micromachined detector. Although the VOA s ion mobility spectrometer and the Microanalyzer s differential mobility spectrometer (DMS) are related detector technologies, the DMS was more amenable to micromachining. This paper will present data from the initial assessment of the Microanalyzer. The instrument was challenged with mixtures that simulated the VOCs typically detected in closed-environment atmospheres.

  6. Creating ‘obesogenic realities’; do our methodological choices make a difference when measuring the food environment?

    PubMed Central

    2013-01-01

    Background The use of Geographical Information Systems (GIS) to objectively measure ‘obesogenic’ food environment (foodscape) exposure has become common-place. This increase in usage has coincided with the development of a methodologically heterogeneous evidence-base, with subsequent perceived difficulties for inter-study comparability. However, when used together in previous work, different types of food environment metric have often demonstrated some degree of covariance. Differences and similarities between density and proximity metrics, and within methodologically different conceptions of density and proximity metrics need to be better understood. Methods Frequently used measures of food access were calculated for North East England, UK. Using food outlet data from local councils, densities of food outlets per 1000 population and per km2 were calculated for small administrative areas. Densities (counts) were also calculated based on population-weighted centroids of administrative areas buffered at 400/800/1000m street network and Euclidean distances. Proximity (street network and Euclidean distances) from these centroids to the nearest food outlet were also calculated. Metrics were compared using Spearman’s rank correlations. Results Measures of foodscape density and proximity were highly correlated. Densities per km2 and per 1000 population were highly correlated (rs = 0.831). Euclidean and street network based measures of proximity (rs = 0.865) and density (rs = 0.667-0.764, depending on neighbourhood size) were also highly correlated. Density metrics based on administrative areas and buffered centroids of administrative areas were less strongly correlated (rs = 0.299-0.658). Conclusions Density and proximity metrics were largely comparable, with some exceptions. Whilst results suggested a substantial degree of comparability across existing studies, future comparability could be ensured by moving towards a more standardised set of

  7. Assemblies for in vitro measurement of bioadhesive strength and retention characteristics in simulated vaginal environment.

    PubMed

    Vermani, Kavita; Garg, Sanjay; Zaneveld, Lourens J D

    2002-10-01

    The vaginal route of administration offers a promising option for local and systemic delivery of drugs. Conventional vaginal formulations are associated with limitations of poor retention, leakage, and messiness, thereby causing inconvenience to users. To overcome these limitations, formulations that adhere to the vaginal mucosa for a sufficient period of time need to be developed. Bioadhesion and retention are desirable characteristics of a vaginal formulation to achieve desired efficacy. These properties can be built in during formulation development by the use of bioadhesive polymers. In the present study, assemblies for in vitro measurement of bioadhesive strength and retention characteristics of vaginal formulations have been developed. A modified simulated vaginal fluid (SVFM) was used to simulate vaginal conditions for bioadhesion studies. Cellophane hydrated with SVFM and isolated sheep vaginal mucosa were used as model membranes. The bioadhesive potential of various polymers and their combinations was evaluated. Among the polymers evaluated, xanthan gum (XG), sodium alginate (SA), Polycarbophil (PC), and their combinations (XG + SA and XG + PC) were found to possess significant bioadhesive strength. In retention experiments, XG, SA, and combinations (XG + SA and XG + PC) were retained in isolated sheep vaginal tissue, while PC exhibited poor retention under experimental conditions. Based on the results of the study conducted, XG, SA, and combinations (XG + SA and XG + PC) have been proposed as potential candidates for developing bioadhesive vaginal drug delivery systems. PMID:12455472

  8. Measurement of gas/water uptake coefficients for trace gases active in the marine environment

    SciTech Connect

    Davidovits, P. . Dept. of Chemistry); Worsnop, D.W.; Zahniser, M.S.; Kolb, C.E. . Center for Chemical and Environmental Physics)

    1992-02-01

    Ocean produced reduced sulfur compounds including dimethylsulfide (DMS), hydrogen sulfide (H{sub 2}S), carbon disulfide (CS{sub 2}), methyl mercaptan (CH{sub 3}CH) and carbonyl sulfide (OCS) deliver a sulfur burden to the atmosphere which is roughly equal to sulfur oxides produced by fossil fuel combustion. These species and their oxidation products dimethyl sulfoxide (DMSO), dimethyl sulfone (DMSO{sub 2}) and methane sulfonic acid (MSA) dominate aerosol and CCN production in clean marine air. Furthermore, oxidation of reduced sulfur species will be strongly influenced by NO{sub x}/O{sub 3} chemistry in marine atmospheres. The multiphase chemical processes for these species must be understood in order to study the evolving role of combustion produced sulfur oxides over the oceans. We have measured the chemical and physical parameters affecting the uptake of reduced sulfur compounds, their oxidation products, ozone, and nitrogen oxides by the ocean's surface, and marine clouds, fogs, and aerosols. These parameters include: gas/surface mass accommodation coefficients; physical and chemically modified (effective) Henry's law constants; and surface and liquid phase reaction constants. These parameters are critical to understanding both the interaction of gaseous trace species with cloud and fog droplets and the deposition of trace gaseous species to dew covered, fresh water and marine surfaces.

  9. Exploring social sensing techniques for measuring rainfall and flood response in urban environments

    NASA Astrophysics Data System (ADS)

    Koole, Wouter; Sips, Robert-Jan; ten Veldhuis, Marie-claire

    2016-04-01

    Extreme rainfall is expected to occur more often in the future as a result of climate change. To be able to react to this, urban water managers need to accurately know vulnerable spots in the city, as well as the potential impact to society. Currently, detailed information about rainfall intensities in cities, and effects of intense storm events on urban societies is lacking. In this study, we will present first results of social sensing experiments to measure rainfall and flooding using a smartphone app. Users of the app are asked to submit rainfall reports by selecting an rainfall class from a pre-defined list of (6) classes, to register time and location and to make a photo of the rainfall. Rainfall photos will be used in a future experiment for automated retrieval of rainfall classes using computer vision techniques. With the experiments we aim to validate rainfall observations made by lay people and to evaluate factors that influence the willingness of users to contribute observations. The results show that users consistently distinguish heavy and extreme rainfall from drizzle and mild rainfall, but have difficulty in making more detailed distinctions. The main factor driving willingness to contribute to the social rainfall sensing experiments is the perceived usefulness of rainfall reporting.

  10. Impact of automation: Measurement of performance, workload and behaviour in a complex control environment.

    PubMed

    Balfe, Nora; Sharples, Sarah; Wilson, John R

    2015-03-01

    This paper describes an experiment that was undertaken to compare three levels of automation in rail signalling; a high level in which an automated agent set routes for trains using timetable information, a medium level in which trains were routed along pre-defined paths, and a low level where the operator (signaller) was responsible for the movement of all trains. These levels are described in terms of a Rail Automation Model based on previous automation theory (Parasuraman et al., 2000). Performance, subjective workload, and signaller activity were measured for each level of automation running under both normal operating conditions and abnormal, or disrupted, conditions. The results indicate that perceived workload, during both normal and disrupted phases of the experiment, decreased as the level of automation increased and performance was most consistent (i.e. showed the least variation between participants) with the highest level of automation. The results give a strong case in favour of automation, particularly in terms of demonstrating the potential for automation to reduce workload, but also suggest much benefit can achieved from a mid-level of automation potentially at a lower cost and complexity. PMID:25479974

  11. Produced water toxicity tests accurately measure the produced water toxicity in marine environments?

    SciTech Connect

    Douglas, W.S.; Veil, J.A.

    1996-10-01

    U.S. Environmental Protection Agency (EPA) Region VI has issued a general permit for offshore oil and gas discharges to the Gulf of Mexico that places numerical limits on whole effluent toxicity (WEI) for produced water. Recently proposed EPA general permits for other produced water discharges in Regions VI and X also include enforceable numerical limits on WET. Clearly, the industry will be conducting extensive produced water WET testing. Unfortunately, the WET test may not accurately measure the toxicity of the chemical constituents of produced water. Rather the mortality of test organisms may be attributable to (1) the high salinity of produced water, which causes salinity shock to the organisms, or (2) an ionic imbalance caused by excesses or deficiencies of one or more of seawater`s essential ions in the test chambers. Both of these effects are likely to be mitigated in actual offshore discharge settings, where the receiving water will be seawater and substantial dilution will be probable. Thus, the additional salinity of produced water will be rapidly assimilated, and the proper marine ionic balance will be quickly restored. Regulatory authorities should be aware of these factors when interpreting WET test results.

  12. Potential for measurement of the distribution of DNA folds in complex environments using Correlated X-ray Scattering

    NASA Astrophysics Data System (ADS)

    Schenk, Gundolf; Krajina, Brad; Spakowitz, Andrew; Doniach, Sebastian

    2016-12-01

    In vivo chromosomal behavior is dictated by the organization of genomic DNA at length scales ranging from nanometers to microns. At these disparate scales, the DNA conformation is influenced by a range of proteins that package, twist and disentangle the DNA double helix, leading to a complex hierarchical structure that remains undetermined. Thus, there is a critical need for methods of structural characterization of DNA that can accommodate complex environmental conditions over biologically relevant length scales. Based on multiscale molecular simulations, we report on the possibility of measuring supercoiling in complex environments using angular correlations of scattered X-rays resulting from X-ray free electron laser (xFEL) experiments. We recently demonstrated the observation of structural detail for solutions of randomly oriented metallic nanoparticles [D. Mendez et al., Philos. Trans. R. Soc. B 360 (2014) 20130315]. Here, we argue, based on simulations, that correlated X-ray scattering (CXS) has the potential for measuring the distribution of DNA folds in complex environments, on the scale of a few persistence lengths.

  13. Measuring and Modeling Solute Transport in the Rootzone: Protecting the Receiving Water Environments of the Coral Atolls of Tonga

    NASA Astrophysics Data System (ADS)

    Clothier, B. E.; van der Velde, M.; Green, S. R.; Gee, G. W.; Manu, V.; Menoniti, V.; Vanclooster, M.

    2005-05-01

    Intensification of agriculture on the raised coral atolls of the Tongan archipelago, notably through squash-pumpkin production, has lead to increased use of agrichemicals. Agrichemicals, both fertilisers and pesticides, pose a risk to these fragile environments. Sustainable land-management practices are needed for small-island developing states. On Tongatapu, solutes leaving the rootzone of the squash can rapidly find their way to the underlying freshwater lenses. These lenses are hydraulically linked to the internal lagoon, and the fringing reefs. We have used buried, non-suction fluxmeters to monitor both the quantity and quality of drainage leaving the rootzone of squash. Fertiliser is traditionally applied at planting. During establishment of the squash in 2003, some 350 mm of rain fell, with 70 % of this leaving the rootzone of this permeable soil as drainage. The concentration of nitrate-N in the drainage water was measured at around 50 mg-N/L. All of the initial fertiliser dressing had been lost, along with N mineralised from the plowed-in grass. Pesticides are needed in humid tropical environments to control weeds, pests and diseases. These chemicals can leach though the rootzone to contaminate receiving waters. We modeled the transport and fate of the presticides used in squash production, and we developed a Decision Support Tool (DST). Our DST can be used to select the best pesticides for local conditions, to tailor practices for minimising leaching losses below the rootzone, and to avoid the build-up of residues in the soil. This project, funded by the European Union and NZAID, took a multi-disciplinary approach through measurement and modeling protocols. Our DST enabled us to engage the wider community and stakeholders. There has been increased awareness of the impacts and risks associated with productive land management in the fragile hydrological environments of this small-island developing state.

  14. Radioactivity measurements and dose rate calculations using ERICA tool in the terrestrial environment of Greece.

    PubMed

    Sotiropoulou, Maria; Florou, Heleny; Manolopoulou, Metaxia

    2016-06-01

    In the present study, the radioactivity levels to which terrestrial non-human biota were exposed are examined. Organisms (grass and herbivore mammals) and abiotic components (soil) were collected during the period of 2010 to 2014 from grasslands where sheep and goats were free-range grazing. Natural background radionuclides ((226)Ra, (228)Ra, (228)Th) and artificial radionuclides ((137)Cs, (134)Cs, (131)I) were detected in the collected samples using gamma spectrometry. The actual measured activity concentrations and site-specific data of the studied organisms were imported in ERICA Assessment Tool (version 1.2.0) in order to provide an insight of the radiological dose rates. The highest activity concentrations were detected in samples collected from Lesvos island and the lowest in samples collected from Attiki and Etoloakarnania prefectures. The highest contribution to the total dose rate was clearly derived from the internal exposure and is closely related to the exposure to alpha emitters of natural background ((226)Ra and (228)Th). The Fukushima-derived traces of (137)Cs, (134)Cs, and (131)I, along with the residual (137)Cs, resulted in quite low contribution to the total dose rate. The obtained results may strengthen the adaptation of software tools to a wider range of ecosystems and may be proved useful in further research regarding the possible impact of protracted low level ionizing radiation on non-human biota. This kind of studies may contribute to the effective incorporation of dosimetry tools in the development of integrated environmental and radiological impact assessment policies. PMID:26897581

  15. New Ways to Continuous Measurements of Soil Moisture in a Hyper-arid Dune Sand Environment

    NASA Astrophysics Data System (ADS)

    Rödiger, T.; Königer, F.; Bonitz, F.; Siebert, C.

    2014-12-01

    Particularly in arid regions, a profound knowledge about infiltration rates eventually leading to groundwater recharge is the major parameter for any resources management. Unfortunately, in arid areas, the rate of infiltration is one of the most difficult values to derive with sufficient accuracy. In 2010 a 3D monitoring site was developed within a sand-dune belt SW of Riyadh (KSA). At the site, one 45°-sloped and 6 vertical drillings were deepened down to max. 13 m below ground and each is equipped with (i) continuous TDR sensors: Taupe- (sloped drilling) and tube- (vertical drilling) sensors as well as (ii) discrete temperature sensors to allow continuous moisture and temperature monitoring within the upper 13 m. The combination of the chosen sensors and the application of direct push by using a Geoprobe 7730DT guaranteed two major advantages: minimal invasiveness and continuous measurements of the relative dielectric permittivity along the borehole walls. Topp equation (Topp et al. 1980) was used to convert the raw signals from sensor into volumetric water content. To calibrate TDR data, the actual soil-moisture contents in the upper 8 m of the dune were derived from drilling core samples. Within the dune, the moisture fluctuates between 0-10.3 vol.-% and quickly reacts on seasonal climatic impacts in the uppermost 2 m, while moisture below persists at around 1.5 vol.-%. Only precipitation events with exceeding 6 mm/d induce increasing moisture in the uppermost 1.5 m of minimum 1.5 vol.-%. That indicates a threshold for effective precipitation of 6 mm/d below of which no remarkable infiltration occurs. During the observation, we derived from the observed precipitation events and the depth of the resulting infiltration fronts, that the infiltration process is driven by the amount of a singular precipitation event. As a consequence, recharge estimations for the so-called sand seas based on annual or monthly precipitation data are not applicable for the region.

  16. Model-based interpretation of sediment concentration and vertical flux measurements in a shallow estuarine environment

    USGS Publications Warehouse

    Brand, Andreas; Lacy, Jessica R.; Gladding, Steve; Holleman, Rusty; Stacey, Mark

    2015-01-01

    A one-dimensional numerical model describing tidally varying vertical mixing and settling was used to interpret sediment concentrations and vertical fluxes observed in the shoals of South San Francisco Bay by two acoustic Doppler velocimeters (ADVs) at elevations of 0.36 m and 0.72 m above bed. Measured sediment concentrations changed by up to 100 g m−3 over the semidiurnal tidal cycle. These dynamics were dominated by local resuspension and settling. Multiple particle class models suggested the existence of a class with fast settling velocities (ws of 9.0 × 10−4 m s−1 in spring and 5.8 × 10−4 m s−1 in fall) and a slowly settling particle fraction (ws of <1 × 10−7 m s−1 in spring and 1.4 × 10−5 m s−1 in fall). Modeled concentrations of slowly settling particles at 0.36 m were as high as 20 g m−3 during fall and varied with the spring-neap cycle while fine sediment concentrations in spring were constant around 5 g m−3. Analysis of in situ water column floc size distributions suggested that floc properties in the lower part of the water column were most likely governed by particle-size distribution on the bed and not by coagulation, validating our multiple particle size approach. A comparison of different sediment bed models with respect to model performance, sensitivity, and identifiability suggested that the use of a sediment erosion model linear in bottom shear stress τb (E = M (τb − τc)) was the most appropriate choice to describe the field observations when the critical shear stress τc and the proportionality factor M were kept constant.

  17. Photometric Redshift with Bayesian Priors on Physical Properties of Galaxies

    NASA Astrophysics Data System (ADS)

    Tanaka, Masayuki

    2015-03-01

    We present a proof-of-concept analysis of photometric redshifts with Bayesian priors on physical properties of galaxies. This concept is particularly suited for upcoming/on-going large imaging surveys, in which only several broadband filters are available and it is hard to break some of the degeneracies in the multi-color space. We construct model templates of galaxies using a stellar population synthesis code and apply Bayesian priors on physical properties such as stellar mass and star formation rate. These priors are a function of redshift and they effectively evolve the templates with time in an observationally motivated way. We demonstrate that the priors help reduce the degeneracy and deliver significantly improved photometric redshifts. Furthermore, we show that a template error function, which corrects for systematic flux errors in the model templates as a function of rest-frame wavelength, delivers further improvements. One great advantage of our technique is that we simultaneously measure redshifts and physical properties of galaxies in a fully self-consistent manner, unlike the two-step measurements with different templates often performed in the literature. One may rightly worry that the physical priors bias the inferred galaxy properties, but we show that the bias is smaller than systematic uncertainties inherent in physical properties inferred from the spectral energy distribution fitting and hence is not a major issue. We will extensively test and tune the priors in the on-going Hyper Suprime-Cam survey and will make the code publicly available in the future.

  18. Prior Knowledge Improves Decoding of Finger Flexion from Electrocorticographic Signals

    PubMed Central

    Wang, Z.; Ji, Q.; Miller, K. J.; Schalk, Gerwin

    2011-01-01

    Brain–computer interfaces (BCIs) use brain signals to convey a user’s intent. Some BCI approaches begin by decoding kinematic parameters of movements from brain signals, and then proceed to using these signals, in absence of movements, to allow a user to control an output. Recent results have shown that electrocorticographic (ECoG) recordings from the surface of the brain in humans can give information about kinematic parameters (e.g., hand velocity or finger flexion). The decoding approaches in these studies usually employed classical classification/regression algorithms that derive a linear mapping between brain signals and outputs. However, they typically only incorporate little prior information about the target movement parameter. In this paper, we incorporate prior knowledge using a Bayesian decoding method, and use it to decode finger flexion from ECoG signals. Specifically, we exploit the constraints that govern finger flexion and incorporate these constraints in the construction, structure, and the probabilistic functions of the prior model of a switched non-parametric dynamic system (SNDS). Given a measurement model resulting from a traditional linear regression method, we decoded finger flexion using posterior estimation that combined the prior and measurement models. Our results show that the application of the Bayesian decoding model, which incorporates prior knowledge, improves decoding performance compared to the application of a linear regression model, which does not incorporate prior knowledge. Thus, the results presented in this paper may ultimately lead to neurally controlled hand prostheses with full fine-grained finger articulation. PMID:22144944

  19. Emission Measurements of Lunar Analogues Measured in a Simulated Lunar Environment for Interpretation of Data Returned from the Diviner Lunar Radiometer on NASA’s Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Thomas, I. R.; Bowles, N. E.; Greenhagen, B. T.; Paige, D. A.

    2009-12-01

    A lunar thermal environment simulator has been constructed, in order to measure emission spectra of lunar analogue minerals in the same thermal environment as is present on the surface of the Moon. This data is directly comparable to measurements made by the Diviner instrument, currently in orbit around the Moon onboard the Lunar Reconnaissance Orbiter (LRO), allowing the composition of the Moon’s surface to be further determined, as part of the Diviner Compositional Investigation[1]. Diviner is a nine-channel infrared mapping radiometer, currently making high resolution (~160m per pixel) observations of the lunar surface from a ~50km lunar orbit[2]. The instrument’s filters are designed to map the temperature, mineralogy, albedo, rock abundance and bulk thermal properties of the surface regolith (soil)[2]. Three channels, located around 8µm, are capable of determining the spectral location of the Christiansen Feature (CF)[3], the primary spectral feature observed in mid-infrared measurements of the Moon[4,5]. Four other channels, from 13 to 400µm, are capable of mapping variations in emissivity of the lunar surface. The CF of a feldspathic mineral is located at a shorter wavelength than a mafic mineral, hence this emissivity maximum can be used as a compositional indicator[6,7]. It is observed as an emissivity maximum, and is enhanced by the lunar environment. In the top few hundreds of microns, at low to mid-latitudes during the daytime, large thermal gradients are induced due to very low heat transport within the lunar regolith[8,9,10,11]. The surface is cooled as it radiates to cold space, but soil transparency in the spectra around the CF region causes radiation to be emitted from the deeper, hotter layers, producing an emission maximum. Regolith grain size, mixing ratios, and the lack of atmosphere on the Moon also affect the shape and location of the CF[6,7,9,12]. The lunar thermal environment simulator creates an equivalent thermal gradient in lunar

  20. Spherical EUV and Plasma Spectrometer (seps) -a Monitor to Measure the Plasma and EUV Environment in Space

    NASA Astrophysics Data System (ADS)

    Brunner, Raimund; Schmidtke, Gerhard; Konz, Werner; Pfeffer, Wilfried

    A low-cost monitor to measure the EUV and plasma environment in space is presented. The device consists of three (or more) isolated spheres, a metallic sphere, one or more highly trans-parent Inner Grids and Outer Grids. Each one is being connected to a sensitive floating elec-trometer. By setting different potentials to the grids as well as to the sphere and varying one or more of their voltages, measurements of spectral solar EUV irradiance (15-200 nm), of local plasma parameters such as electron and ion densities, electron energies and temperatures as well as ion compositions and debris events can be derived from the current recordings. This detector does not require any (solar) pointing device. The primary goal is to study the impact of solar activity events (e.g. CMEs) as well as subsequent reactions of the ionospheric/thermospheric systems (including space weather occurences). The capability of SEPS for measuring EUV pho-ton fluxes as well as plasma parameters in the energy range from 0 to +/-70 eV is demonstrated by laboratory measurements as performed in the IPM laboratory, at BESSY-PTB electron syn-chrotron in Berlin and at ESA/ESTEC plasma chamber. Based on the laboratory recording of plasma recombination EUV emission the sensor is suitable to detect also auroral and airglow radiations. -The state of the art in the development of this device is reported.