Science.gov

Sample records for ground survey methods

  1. Ground vegetation monitoring in Swiss forests: comparison of survey methods and implications for trend assessments.

    PubMed

    Thimonier, Anne; Kull, Peter; Keller, Walter; Moser, Barbara; Wohlgemuth, Thomas

    2011-03-01

    At Swiss long-term forest ecosystem research sites, ground vegetation was assessed during the period 1994-2003/2008 following two approaches: (1) visual assessment of the cover of species occurring in sixteen 1 m(2) quadrats, distributed over a 43 × 43 m area, and (2) phytosociological relevés in concentric circular plots of 30, 200, and 500 m(2). We first compared the two approaches with respect to diversity assessment. The number of species recorded in the 16 quadrats was in general higher than in the 30 m(2) plot and it represented 42% to 108% of the number of species recorded in the 500 m(2) plot. In a second step, we tested whether any temporal trends were apparent. In a few cases, a decrease or increase in Landolt's mean indicator values for light, nitrogen availability, soil pH, soil moisture, or temperature was found to be significant. However, these changes were usually restricted to one approach or one area. The only clear trend was detected in an unmanaged former coppice beech stand, for which all survey approaches indicated canopy closure. At another site, vegetation reacted to the local opening of the canopy following windthrow. In a third step, we compared the leaf area index (LAI), measured with an LAI-2000 instrument (Licor, Inc.) over each quadrat, with the indicator value of the vegetation for light (L). Within a site, there was no clear relationship between LAI and L values per quadrat. In contrast, across all sites, the relationship between LAI and L, averaged per site for all available years, was highly significant. PMID:21049285

  2. METHOD OF LOCATING GROUNDS

    DOEpatents

    Macleish, K.G.

    1958-02-11

    ABS>This patent presents a method for locating a ground in a d-c circult having a number of parallel branches connected across a d-c source or generator. The complete method comprises the steps of locating the ground with reference to the mildpoint of the parallel branches by connecting a potentiometer across the terminals of the circuit and connecting the slider of the potentiometer to ground through a current indicating instrument, adjusting the slider to right or left of the mildpoint so as to cause the instrument to indicate zero, connecting the terminal of the network which is farthest from the ground as thus indicated by the potentiometer to ground through a condenser, impressing a ripple voltage on the circuit, and then measuring the ripple voltage at the midpoint of each parallel branch to find the branch in which is the lowest value of ripple voltage, and then measuring the distribution of the ripple voltage along this branch to determine the point at which the ripple voltage drops off to zero or substantially zero due to the existence of a ground. The invention has particular application where a circuit ground is present which will disappear if the normal circuit voltage is removed.

  3. Ground-penetrating radar methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ground-penetrating radar geophysical methods are finding greater and greater use in agriculture. With the ground-penetrating radar (GPR) method, an electromagnetic radio energy (radar) pulse is directed into the subsurface, followed by measurement of the elapsed time taken by the radar signal as it ...

  4. Site survey method and apparatus

    DOEpatents

    Oldham, J.G.; Spencer, C.R.; Begley, C.L.; Meyer, H.R.

    1991-06-18

    The disclosure of the invention is directed to a site survey ground vehicle based apparatus and method for automatically detecting source materials, such as radioactivity, marking the location of the source materials, such as with paint, and mapping the location of the source materials on a site. The apparatus of the invention is also useful for collecting and analyzing samples. The apparatus includes a ground vehicle, detectors mounted at the front of the ground vehicle, and individual detector supports which follow somewhat irregular terrain to allow consistent and accurate detection, and autolocation equipment. 19 figures.

  5. Site survey method and apparatus

    DOEpatents

    Oldham, James G.; Spencer, Charles R.; Begley, Carl L.; Meyer, H. Robert

    1991-06-18

    The disclosure of the invention is directed to a site survey ground vehicle based apparatus and method for automatically detecting source materials, such as radioactivity, marking the location of the source materials, such as with paint, and mapping the location of the source materials on a site. The apparatus of the invention is also useful for collecting and analyzing samples. The apparatus includes a ground vehicle, detectors mounted at the front of the ground vehicle, and individual detector supports which follow somewhat irregular terrain to allow consistent and accurate detection, and autolocation equipment.

  6. Method of locating ground faults

    NASA Astrophysics Data System (ADS)

    Patterson, Richard L.; Rose, Allen H.; Cull, Ronald C.

    1994-11-01

    The present invention discloses a method of detecting and locating current imbalances such as ground faults in multiwire systems using the Faraday effect. As an example, for 2-wire or 3-wire (1 ground wire) electrical systems, light is transmitted along an optical path which is exposed to magnetic fields produced by currents flowing in the hot and neutral wires. The rotations produced by these two magnetic fields cancel each other, therefore light on the optical path does not read the effect of either. However, when a ground fault occurs, the optical path is exposed to a net Faraday effect rotation due to the current imbalance thereby exposing the ground fault.

  7. Method of locating ground faults

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L. (Inventor); Rose, Allen H. (Inventor); Cull, Ronald C. (Inventor)

    1994-01-01

    The present invention discloses a method of detecting and locating current imbalances such as ground faults in multiwire systems using the Faraday effect. As an example, for 2-wire or 3-wire (1 ground wire) electrical systems, light is transmitted along an optical path which is exposed to magnetic fields produced by currents flowing in the hot and neutral wires. The rotations produced by these two magnetic fields cancel each other, therefore light on the optical path does not read the effect of either. However, when a ground fault occurs, the optical path is exposed to a net Faraday effect rotation due to the current imbalance thereby exposing the ground fault.

  8. Locating Desired Source Rocks by Using Shallow Ground Penetrating Radar and Seismic Survey Methods in western Washington, Pacific Northwest of the U.S

    NASA Astrophysics Data System (ADS)

    Cakir, R.; Meng, X.; Butler, Q.; Jenkins, J.; Keck, J.; Walsh, T. J.

    2015-12-01

    The Washington State Department of Natural Resources (WADNR) manages 2.1 million acres of forested state trust lands in Washington. WADNR sells timber and other agricultural products to help fund local services and the construction of institutions such as public schools and universities. Quality of rocks used as a surface on the roads built to access the timber is the essential and selecting appropriate rock quarry locations is challenging. Traditional borehole drilling methods only provide information from discrete locations. The study was conducted in the Capitol Forest area of western Washington. In our previous study, we suggested that a combination of P-wave seismic and ground penetrating radar (GPR) can be a rapid, comprehensive and cost effective alternative for identifying desired rock sources. In this study, we further improved upon that method and accomplished the following: 1) rock quality at a relatively fine resolution was distinguished and 2) the spatial variability of the rock was identified. Both 450 MHz and 80 MHz GPR antennas were used to obtain high resolution radargrams in the near-surface zone with 5m maximum penetration depth and lower resolution radargrams in the deeper subsurface zone with about 20m maximum penetration depth. We then correlated the GPR radargrams with P-wave velocities using the refraction survey data as well as S-wave velocities, estimated using Multi-Channel Analysis of Surface Waves (MASW) survey data. Additionally, nearby test pits and boreholes (maximum depth = 15 meters) were used to confirm the geophysical measurements. Our study results demonstrate that the combination of GPR, using the two antennas, and seismic surveys provides very useful subsurface information regarding quality and spatial distribution of the rocks beneath the overburden. Subsurface images gathered from these combined geophysical methods do assist quarry operators to rapidly locate the desired rock sources.

  9. The WASP and NGTS ground-based transit surveys

    NASA Astrophysics Data System (ADS)

    Wheatley, P. J.

    2015-10-01

    I will review the current status of ground-based exoplanet transit surveys, using the Wide Angle Search for Planets (WASP) and the Next Generation Transit Survey (NGTS) as specific examples. I will describe the methods employed by these surveys and show how planets from Neptune to Jupiter-size are detected and confirmed around bright stars. I will also give an overview of the remarkably wide range of exoplanet characterization that is made possible with large-telescope follow up of these bright transiting systems. This characterization includes bulk composition and spin-orbit alignment, as well as atmospheric properties such as thermal structure, composition and dynamics. Finally, I will outline how ground-based photometric studies of transiting planets will evolve with the advent of new space-based surveys such as TESS and PLATO.

  10. Assessing modern ground survey methods and airborne laser scanning for digital terrain modelling: A case study from the Lake District, England

    NASA Astrophysics Data System (ADS)

    Gallay, Michal; Lloyd, Christopher D.; McKinley, Jennifer; Barry, Lorraine

    2013-02-01

    This paper compares the applicability of three ground survey methods for modelling terrain: one man electronic tachymetry (TPS), real time kinematic GPS (GPS), and terrestrial laser scanning (TLS). Vertical accuracy of digital terrain models (DTMs) derived from GPS, TLS and airborne laser scanning (ALS) data is assessed. Point elevations acquired by the four methods represent two sections of a mountainous area in Cumbria, England. They were chosen so that the presence of non-terrain features is constrained to the smallest amount. The vertical accuracy of the DTMs was addressed by subtracting each DTM from TPS point elevations. The error was assessed using exploratory measures including statistics, histograms, and normal probability plots. The results showed that the internal measurement accuracy of TPS, GPS, and TLS was below a centimetre. TPS and GPS can be considered equally applicable alternatives for sampling the terrain in areas accessible on foot. The highest DTM vertical accuracy was achieved with GPS data, both on sloped terrain (RMSE 0.16 m) and flat terrain (RMSE 0.02 m). TLS surveying was the most efficient overall but veracity of terrain representation was subject to dense vegetation cover. Therefore, the DTM accuracy was the lowest for the sloped area with dense bracken (RMSE 0.52 m) although it was the second highest on the flat unobscured terrain (RMSE 0.07 m). ALS data represented the sloped terrain more realistically (RMSE 0.23 m) than the TLS. However, due to a systematic bias identified on the flat terrain the DTM accuracy was the lowest (RMSE 0.29 m) which was above the level stated by the data provider. Error distribution models were more closely approximated by normal distribution defined using median and normalized median absolute deviation which supports the use of the robust measures in DEM error modelling and its propagation.

  11. 29. Historic American Buildings Survey Ground floor Plan Framing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Historic American Buildings Survey Ground floor Plan - Framing and seating Original Plan by Benjamin H. Latrobe 1816 Copy of plan in Church Office - St. John's Church, Sixteenth & H Streets Northwest, Washington, District of Columbia, DC

  12. Ground-Cover Measurements: Assessing Correlation Among Aerial and Ground-Based Methods

    NASA Astrophysics Data System (ADS)

    Booth, D. Terrance; Cox, Samuel E.; Meikle, Tim; Zuuring, Hans R.

    2008-12-01

    Wyoming’s Green Mountain Common Allotment is public land providing livestock forage, wildlife habitat, and unfenced solitude, amid other ecological services. It is also the center of ongoing debate over USDI Bureau of Land Management’s (BLM) adjudication of land uses. Monitoring resource use is a BLM responsibility, but conventional monitoring is inadequate for the vast areas encompassed in this and other public-land units. New monitoring methods are needed that will reduce monitoring costs. An understanding of data-set relationships among old and new methods is also needed. This study compared two conventional methods with two remote sensing methods using images captured from two meters and 100 meters above ground level from a camera stand (a ground, image-based method) and a light airplane (an aerial, image-based method). Image analysis used SamplePoint or VegMeasure software. Aerial methods allowed for increased sampling intensity at low cost relative to the time and travel required by ground methods. Costs to acquire the aerial imagery and measure ground cover on 162 aerial samples representing 9000 ha were less than 3000. The four highest correlations among data sets for bare ground—the ground-cover characteristic yielding the highest correlations (r)—ranged from 0.76 to 0.85 and included ground with ground, ground with aerial, and aerial with aerial data-set associations. We conclude that our aerial surveys are a cost-effective monitoring method, that ground with aerial data-set correlations can be equal to, or greater than those among ground-based data sets, and that bare ground should continue to be investigated and tested for use as a key indicator of rangeland health.

  13. Aerial surveys adjusted by ground surveys to estimate area occupied by black-tailed prairie dog colonies

    USGS Publications Warehouse

    Sidle, John G.; Augustine, David J.; Johnson, Douglas H.; Miller, Sterling D.; Cully, Jack F., Jr.; Reading, Richard P.

    2012-01-01

    Aerial surveys using line-intercept methods are one approach to estimate the extent of prairie dog colonies in a large geographic area. Although black-tailed prairie dogs (Cynomys ludovicianus) construct conspicuous mounds at burrow openings, aerial observers have difficulty discriminating between areas with burrows occupied by prairie dogs (colonies) versus areas of uninhabited burrows (uninhabited colony sites). Consequently, aerial line-intercept surveys may overestimate prairie dog colony extent unless adjusted by an on-the-ground inspection of a sample of intercepts. We compared aerial line-intercept surveys conducted over 2 National Grasslands in Colorado, USA, with independent ground-mapping of known black-tailed prairie dog colonies. Aerial line-intercepts adjusted by ground surveys using a single activity category adjustment overestimated colonies by ≥94% on the Comanche National Grassland and ≥58% on the Pawnee National Grassland. We present a ground-survey technique that involves 1) visiting on the ground a subset of aerial intercepts classified as occupied colonies plus a subset of intercepts classified as uninhabited colony sites, and 2) based on these ground observations, recording the proportion of each aerial intercept that intersects a colony and the proportion that intersects an uninhabited colony site. Where line-intercept techniques are applied to aerial surveys or remotely sensed imagery, this method can provide more accurate estimates of black-tailed prairie dog abundance and trends

  14. Investigations into near-real-time surveying for geophysical data collection using an autonomous ground vehicle

    USGS Publications Warehouse

    Phelps, Geoffrey A.; Ippolito, C.; Lee, R.; Spritzer, R.; Yeh, Y.

    2014-01-01

    The U.S. Geological Survey and the National Aeronautics and Space Administration are cooperatively investigating the utility of unmanned vehicles for near-real-time autonomous surveys of geophysical data collection. Initially focused on unmanned ground vehicle collection of magnetic data, this cooperative effort has brought unmanned surveying, precision guidance, near-real-time communication, on-the-fly data processing, and near-real-time data interpretation into the realm of ground geophysical surveying, all of which offer advantages over current methods of manned collection of ground magnetic data. An unmanned ground vehicle mission has demonstrated that these vehicles can successfully complete missions to collect geophysical data, and add advantages in data collection, processing, and interpretation. We view the current experiment as an initial phase in further unmanned vehicle data-collection missions, including aerial surveying.

  15. July 1973 ground survey of active Central American volcanoes

    NASA Technical Reports Server (NTRS)

    Stoiber, R. E. (Principal Investigator); Rose, W. I., Jr.

    1973-01-01

    The author has identified the following significant results. Ground survey has shown that thermal anomalies of various sizes associated with volcanic activity at several Central American volcanoes should be detectable from Skylab. Anomalously hot areas of especially large size (greater than 500 m in diameter) are now found at Santiaguito and Pacaya volcanoes in Guatemala and San Cristobal in Nicaragua. Smaller anomalous areas are to be found at least seven other volcanoes. This report is completed after ground survey of eleven volcanoes and ground-based radiation thermometry mapping at these same points.

  16. Generating Ground Reference Data for a Global Impervious Surface Survey

    NASA Technical Reports Server (NTRS)

    Tilton, James C.; De Colstoun, Eric Brown; Wolfe, Robert E.; Tan, Bin; Huang, Chengquan

    2012-01-01

    We are developing an approach for generating ground reference data in support of a project to produce a 30m impervious cover data set of the entire Earth for the years 2000 and 2010 based on the Landsat Global Land Survey (GLS) data set. Since sufficient ground reference data for training and validation is not available from ground surveys, we are developing an interactive tool, called HSegLearn, to facilitate the photo-interpretation of 1 to 2 m spatial resolution imagery data, which we will use to generate the needed ground reference data at 30m. Through the submission of selected region objects and positive or negative examples of impervious surfaces, HSegLearn enables an analyst to automatically select groups of spectrally similar objects from a hierarchical set of image segmentations produced by the HSeg image segmentation program at an appropriate level of segmentation detail, and label these region objects as either impervious or nonimpervious.

  17. Ground radon survey of a geothermal area in Hawaii

    NASA Astrophysics Data System (ADS)

    Cox, Malcolm E.

    Rates of ground radon emanation, in the Puna geothermal area on the lower east rift of Kilauea volcano, were measured by alpha particle sensitive cellulose nitrate films. The survey successfully defined an area of thermal significance associated with the rift structure, and suggests that a thermally driven ground gas convection system exists within, and peripheral to, the rift. This type of survey was found suitable for the basaltic island environment characteristic of Hawaii and is now used in Hawaii as a routine geothermal exploration technique.

  18. Quantifying Stream Habitat: Relative Effort Versus Quality of Competing Remote Sensing & Ground-Based Survey Techniques

    NASA Astrophysics Data System (ADS)

    Bangen, S. G.; Wheaton, J. M.; Bouwes, N.

    2010-12-01

    Numerous field and analytical methods exist to assist in the quantification of the quantity and quality of in-stream habitat for salmonids. These methods range from field sketches or ‘tape and stick’ ground-based surveys, through to spatially explicit topographic and aerial photographic surveys from a mix of ground-based and remotely sensed airborne platforms. Although some investigators have assessed the quality of specific individual survey methods, the inter-comparison of competing techniques across a diverse range of habitat conditions (wadeable headwater channels to non-wadeable mainstem channels) has not yet been elucidated. In this study, we seek to quantify relative quality (i.e. accuracy, precision, extent) of habitat metrics and inventories derived from different ground-based and remotely sensed surveys of varying degrees of sophistication, as well as enumerate the effort and cost in completing the surveys. Over the summer of 2010, seven sample reaches of varying habitat complexity were surveyed in the Lemhi River Basin, Idaho, USA. Three different traditional (“stick and tape”) survey techniques were used, including a variant using map-grade GPS. Complete topographic/bathymetric surveys were attempted at each site using separate rtkGPS, total station, ground-based LiDaR, boat-based echo-sounding (w/ ADCP), traditional airborne LiDaR, and imagery-based spectral methods. Separate, georectified aerial imagery surveys were acquired using a tethered blimp, a drone UAV, and a traditional fixed-wing aircraft. Preliminary results from the surveys highlight that no single technique works across the full range of conditions where stream habitat surveys are needed. The results are helpful for understanding the strengths and weaknesses of each approach in specific conditions, and how a hybrid of data acquisition methods can be used to build a more complete quantification of habitat conditions in rivers.

  19. Simulating the Performance of Ground-Based Optical Asteroid Surveys

    NASA Astrophysics Data System (ADS)

    Christensen, Eric J.; Shelly, Frank C.; Gibbs, Alex R.; Grauer, Albert D.; Hill, Richard E.; Johnson, Jess A.; Kowalski, Richard A.; Larson, Stephen M.

    2014-11-01

    We are developing a set of asteroid survey simulation tools in order to estimate the capability of existing and planned ground-based optical surveys, and to test a variety of possible survey cadences and strategies. The survey simulator is composed of several layers, including a model population of solar system objects and an orbital integrator, a site-specific atmospheric model (including inputs for seeing, haze and seasonal cloud cover), a model telescope (with a complete optical path to estimate throughput), a model camera (including FOV, pixel scale, and focal plane fill factor) and model source extraction and moving object detection layers with tunable detection requirements. We have also developed a flexible survey cadence planning tool to automatically generate nightly survey plans. Inputs to the cadence planner include camera properties (FOV, readout time), telescope limits (horizon, declination, hour angle, lunar and zenithal avoidance), preferred and restricted survey regions in RA/Dec, ecliptic, and Galactic coordinate systems, and recent coverage by other asteroid surveys. Simulated surveys are created for a subset of current and previous NEO surveys (LINEAR, Pan-STARRS and the three Catalina Sky Survey telescopes), and compared against the actual performance of these surveys in order to validate the model’s performance. The simulator tracks objects within the FOV of any pointing that were not discovered (e.g. too few observations, too trailed, focal plane array gaps, too fast or slow), thus dividing the population into “discoverable” and “discovered” subsets, to inform possible survey design changes. Ongoing and future work includes generating a realistic “known” subset of the model NEO population, running multiple independent simulated surveys in coordinated and uncoordinated modes, and testing various cadences to find optimal strategies for detecting NEO sub-populations. These tools can also assist in quantifying the efficiency of novel

  20. Straussian Grounded-Theory Method: An Illustration

    ERIC Educational Resources Information Center

    Thai, Mai Thi Thanh; Chong, Li Choy; Agrawal, Narendra M.

    2012-01-01

    This paper demonstrates the benefits and application of Straussian Grounded Theory method in conducting research in complex settings where parameters are poorly defined. It provides a detailed illustration on how this method can be used to build an internationalization theory. To be specific, this paper exposes readers to the behind-the-scene work…

  1. Plating methods, a survey

    NASA Technical Reports Server (NTRS)

    Berkowitz, J. B.; Emerson, N. H.

    1972-01-01

    Results are presented of a comprehensive search of the literature available, much of which has been generated by the research centers of NASA and its contractors, on plating and coating methods and techniques. Methods covered included: (1) electroplating from aqueous solutions; (2) electroplating from nonaqueous solutions; (3) electroplating from fused-salt baths; (4) electroforming; (5) electroless plating, immersion plating, and mirroring; (6) electroplating from gaseous plasmas; and (7) anodized films and conversion coatings.

  2. Grounded Theory Methods and Qualitative Family Research

    ERIC Educational Resources Information Center

    LaRossa, Ralph

    2005-01-01

    Among the different qualitative approaches that may be relied upon in family theorizing, grounded theory methods (GTM), developed by Barney Glaser and Anselm Strauss, are the most popular. Despite their centrality to family studies and to other fields, however, GTM can be opaque and confusing. Believing that simplifying GTM would allow them to be…

  3. Ground solar radius survey in view of microsatellite missions

    NASA Astrophysics Data System (ADS)

    Delmas, C.; Morand, F.; Laclare, F.; Irbah, A.; Thuillier, G.; Bourget, P.

    For the last 25 years, ground time series of the solar radius have shown (different) apparent variations according to different instruments. The origin of these variations may search in the observer, the instrument, the atmosphere and up to the sun. Ground instruments are automated to reduce the “personnal equation” and place that origin in the atmosphere and/or in the sun. Astrometric satellites scheduled at the end of this decade will perform non ambiguous diameter measurements. A survey of the Solar radius has been initiated in 1975 by Francis Laclare, at the Calern site of the Observatoire de la Côte d’Azur, which have been chosen for hosting the ground segment of the Centre National d’Etudes Spatiales (CNES) Microsatellite PICARD mission, to be launched in 2008. This reference series was obtained by Visual observations of the Sun, with a Solar Astrolabe whose metrological character has to be stressed. Considering the Visual series results, we have compared the solar diameter variations with the solar activity cycle, and we found an opposite phase, for the whole series and at the different times of the cycles. Parallel to that series, CCD measurements were made with the same instrument and gave results which are perfectly blended together, within our quoted uncertainties. Located next to the Solar Astrolabe, DORAYSOL (Définition et Observation du Rayon Solaire) is a second generation instrument, which keeps the major features of the design of its predecessor and, which is designed to increase the number of CCD measurements and to be eventually automated. Since 1999, both series overlap correctly within our quoted uncertainties. Some information is added to explain the pattern of the PICARD mission ground segment, next to those instruments at Calern Observatory, as well as the international network intended to carry out the Sun’s Radius ground survey (R2S3: Réseau de Suivi au Sol du Rayon Solaire).

  4. Data Management for Ground-Based Science Surveys at CASU

    NASA Astrophysics Data System (ADS)

    Irwin, Mike

    2015-12-01

    In this talk I will review the data management facilities at CASU for handling large scale ground-based imaging and spectroscopic surveys. The overarching principle for all science data processing at CASU is to provide an end-to-end system that attempts to deliver fully calibrated optimally extracted data products ready for science use. The talk will outline our progress in achieving this and how end users visualize the state-of-play of the data processing and interact with the final products via our internal data repository.

  5. 30 CFR 77.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND... grounded system, extending to a low-resistance ground field; (c) Any other method of grounding, approved...

  6. 30 CFR 77.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved methods of grounding. 77.700-1 Section... COAL MINES Grounding § 77.700-1 Approved methods of grounding. Metallic sheaths, armors, and conduits... methods of grounding will be approved: (a) A solid connection to metal waterlines having low resistance...

  7. 30 CFR 77.703-1 - Approved methods of grounding.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved methods of grounding. 77.703-1 Section 77.703-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Grounding § 77.703-1 Approved methods of grounding. The methods of grounding stated in §...

  8. 30 CFR 75.704-1 - Approved methods of grounding.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved methods of grounding. 75.704-1 Section... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.704-1 Approved methods of grounding. The methods of grounding stated in § 75.701-1 will also be approved with respect to...

  9. 30 CFR 75.704-1 - Approved methods of grounding.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved methods of grounding. 75.704-1 Section... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.704-1 Approved methods of grounding. The methods of grounding stated in § 75.701-1 will also be approved with respect to...

  10. 30 CFR 77.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Approved methods of grounding. 77.700-1 Section... COAL MINES Grounding § 77.700-1 Approved methods of grounding. Metallic sheaths, armors, and conduits... methods of grounding will be approved: (a) A solid connection to metal waterlines having low resistance...

  11. 30 CFR 75.704-1 - Approved methods of grounding.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Approved methods of grounding. 75.704-1 Section... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.704-1 Approved methods of grounding. The methods of grounding stated in § 75.701-1 will also be approved with respect to...

  12. 30 CFR 77.703-1 - Approved methods of grounding.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Approved methods of grounding. 77.703-1 Section 77.703-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Grounding § 77.703-1 Approved methods of grounding. The methods of grounding stated in §...

  13. Grounded electrical-source airborne transient electromagnetics (GREATEM) survey of Aso Volcano, Japan

    NASA Astrophysics Data System (ADS)

    Ito, Hisatoshi; Kaieda, Hideshi; Mogi, Toru; Jomori, Akira; Yuuki, Youichi

    2014-05-01

    Grounded electrical-source airborne transient electromagnetics (GREATEM), a type of semi-airborne electromagnetics, was used to examine Aso Volcano in south-west Japan, to verify its applicability to surveying deep subsurface resistivity structures. Comparison of the GREATEM resistivity values with those of ground-based transient electromagnetics (TEM) data, repeated GREATEM survey results at the same and different flight heights, and lithologic descriptions indicated that GREATEM can successfully identify underground structures as deep as ~800 m in rugged mountainous areas. An active volcanic region (Naka-Dake crater) was mapped as a low-resistivity zone from the surface to a depth of 100 m. This low-resistivity zone extended to the west-north-west, implying future volcanic activity in this area. Therefore, the GREATEM method is useful for surveying deep structures in large, inaccessible areas, such as volcanic provinces, in a quick, cost-effective way.

  14. 40 CFR 141.401 - Sanitary surveys for ground water systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Sanitary surveys for ground water systems. 141.401 Section 141.401 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.401 Sanitary surveys for ground water systems....

  15. Local Environmental Characterization using Gamma Ground Survey Network

    NASA Astrophysics Data System (ADS)

    Litz, Marc; Burns, David; Katsis, Dimos; Carroll, James

    2013-04-01

    Inexpensive gamma detectors with GPS and wireless communications have been developed and installed to provide a ground survey network for detection of environmental levels of gamma radiation from naturally occurring events (i.e. radon, lightening, solar flares, etc.) and unintended gamma radiation on the battlefield and along transport routes. Signals from lightening and cosmic rays have pulse widths less than 100 us. Pedestrian borne and vehicle borne radiation sources have signatures from millseconds to seconds. The large energy associated with solar initiated disruptions (10^20J) generates a variety of ground level events that can last for hours. Data collected during the 24/7 operation of this gamma network is compared to xray, electron, and ion flux from satellite sensors. Local rainfall data is also utilized to make comparisons to local radon intensity levels. This paper will discuss the time and intensity correlations with corroborating environmental data. If the gamma signals characteristics from local environments and space-based environments can be described with enough detail, it is hoped that automated warning of unexpected radiation events can offer early warning protection to power and energy grid avoiding potentially damaging surges as well as offer local radiation health warning as necessary.

  16. 30 CFR 75.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved methods of grounding. 75.700-1 Section... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.700-1 Approved methods...; in all other systems, the following methods of grounding will be approved: (a) A solid connection...

  17. Survey of Anomaly Detection Methods

    SciTech Connect

    Ng, B

    2006-10-12

    This survey defines the problem of anomaly detection and provides an overview of existing methods. The methods are categorized into two general classes: generative and discriminative. A generative approach involves building a model that represents the joint distribution of the input features and the output labels of system behavior (e.g., normal or anomalous) then applies the model to formulate a decision rule for detecting anomalies. On the other hand, a discriminative approach aims directly to find the decision rule, with the smallest error rate, that distinguishes between normal and anomalous behavior. For each approach, we will give an overview of popular techniques and provide references to state-of-the-art applications.

  18. Ground Water Arsenic Contamination: A Local Survey in India

    PubMed Central

    Kumar, Arun; Rahman, Md. Samiur; Iqubal, Md. Asif; Ali, Mohammad; Niraj, Pintoo Kumar; Anand, Gautam; Kumar, Prabhat; Abhinav; Ghosh, Ashok Kumar

    2016-01-01

    Background: In the present times, arsenic poisoning contamination in the ground water has caused lots of health-related problems in the village population residing in middle Gangetic plain. In Bihar, about 16 districts have been reported to be affected with arsenic poisoning. For the ground water and health assessment, Simri village of Buxar district was undertaken which is a flood plain region of river Ganga. Methods: In this study, 322 water samples were collected for arsenic estimation, and their results were analyzed. Furthermore, the correlation between arsenic contamination in ground water with depth and its distance from river Ganga were analyzed. Results are presented as mean ± standard deviation and total variation present in a set of data was analyzed through one-way analysis of variance. The difference among mean values has been analyzed by applying Dunnett's test. The criterion for statistical significance was set at P < 0.05. Results: This study shows novel findings ever done in this area. Halwa Patti and Doodhi Patti strips were the most affected strips with high-arsenic concentration in hand pumps. Furthermore, a correlation between the arsenic concentration with the depth of the hand pumps and the distance from the river Ganga was also a significant study. Conclusions: The present study concludes that in Simri village there is high contamination of arsenic in ground water in all the strips. Such a huge population is at very high risk leading the village on the verge of causing health hazards among them. Therefore, an immediate strategy is required to combat the present problem. PMID:27625765

  19. Proposed Ground Testing Standard Methods and Techniques

    NASA Technical Reports Server (NTRS)

    Goodnight, Thomas

    2000-01-01

    The methodologies used for prediction for on-orbit microgravity environment needs to be ground validated. The data and models for such validation will be coming from diverse sources. No standardized methodologies have been validated which cover the entire 0 - 300 Hz range. Current ground test data feeds into this process and therefore should be standardized to support both narrow and third octave band analysis.

  20. TESTING GROUND BASED GEOPHYSICAL TECHNIQUES TO REFINE ELECTROMAGNETIC SURVEYS NORTH OF THE 300 AREA HANFORD WASHINGTON

    SciTech Connect

    PETERSEN SW

    2010-12-02

    Airborne electromagnetic (AEM) surveys were flown during fiscal year (FY) 2008 within the 600 Area in an attempt to characterize the underlying subsurface and to aid in the closure and remediation design study goals for the 200-PO-1 Groundwater Operable Unit (OU). The rationale for using the AEM surveys was that airborne surveys can cover large areas rapidly at relatively low costs with minimal cultural impact, and observed geo-electrical anomalies could be correlated with important subsurface geologic and hydrogeologic features. Initial interpretation of the AEM surveys indicated a tenuous correlation with the underlying geology, from which several anomalous zones likely associated with channels/erosional features incised into the Ringold units were identified near the River Corridor. Preliminary modeling resulted in a slightly improved correlation but revealed that more information was required to constrain the modeling (SGW-39674, Airborne Electromagnetic Survey Report, 200-PO-1 Groundwater Operable Unit, 600 Area, Hanford Site). Both time-and frequency domain AEM surveys were collected with the densest coverage occurring adjacent to the Columbia River Corridor. Time domain surveys targeted deeper subsurface features (e.g., top-of-basalt) and were acquired using the HeliGEOTEM{reg_sign} system along north-south flight lines with a nominal 400 m (1,312 ft) spacing. The frequency domain RESOLVE system acquired electromagnetic (EM) data along tighter spaced (100 m [328 ft] and 200 m [656 ft]) north-south profiles in the eastern fifth of the 200-PO-1 Groundwater OU (immediately adjacent to the River Corridor). The overall goal of this study is to provide further quantification of the AEM survey results, using ground based geophysical methods, and to link results to the underlying geology and/or hydrogeology. Specific goals of this project are as follows: (1) Test ground based geophysical techniques for the efficacy in delineating underlying geology; (2) Use ground

  1. The Erosion of a Method: Examples from Grounded Theory

    ERIC Educational Resources Information Center

    Greckhamer, Thomas; Koro-Ljungberg, Mirka

    2005-01-01

    Since its original inception in the 1960s grounded theory has been widely used by many qualitative researchers. However, recently epistemologically different versions of grounded theory have been presented and this epistemological diversity among grounded theorists and the erosion of the method will be the major focus of this paper. The first…

  2. Generating Ground Reference Data for a Global Impervious Surface Survey

    NASA Technical Reports Server (NTRS)

    Tilton, James C.; deColstoun, Eric Brown; Wolfe, Robert E.; Tan, Bin; Huang, Chengquan

    2012-01-01

    We are engaged in a project to produce a 30m impervious cover data set of the entire Earth for the years 2000 and 2010 based on the Landsat Global Land Survey (GLS) data set. The GLS data from Landsat provide an unprecedented opportunity to map global urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such as buildings, roads and parking lots. Finally, with GLS data available for the 1975, 1990, 2000, and 2005 time periods, and soon for the 2010 period, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. Our approach works across spatial scales using very high spatial resolution commercial satellite data to both produce and evaluate continental scale products at the 30m spatial resolution of Landsat data. We are developing continental scale training data at 1m or so resolution and aggregating these to 30m for training a regression tree algorithm. Because the quality of the input training data are critical, we have developed an interactive software tool, called HSegLearn, to facilitate the photo-interpretation of high resolution imagery data, such as Quickbird or Ikonos data, into an impervious versus non-impervious map. Previous work has shown that photo-interpretation of high resolution data at 1 meter resolution will generate an accurate 30m resolution ground reference when coarsened to that resolution. Since this process can be very time consuming when using standard clustering classification algorithms, we are looking at image segmentation as a potential avenue to not only improve the training process but also provide a semi-automated approach for generating the ground reference data. HSegLearn takes as its input a hierarchical set of image segmentations produced by the HSeg image segmentation program [1, 2]. HSegLearn lets an analyst specify pixel locations as being

  3. The Neural Network Method of Corrosion Diagnosis for Grounding Grid

    SciTech Connect

    Hou Zaien; Duan Fujian; Zhang Kecun

    2008-11-06

    Safety of persons, protection of equipment and continuity of power supply are the main objectives of the grounding system of a large electrical installation. For its accurate working status, it is essential to determine every branch resistance in the system. In this paper, we present a neural network method of corrosion diagnosis for the grounding grid based on the neural network theory. The feasibility of this method is discussed by means of its application to a simulant grounding grid.

  4. Digital Sky Surveys from the Ground: Status and Perspectives

    NASA Astrophysics Data System (ADS)

    Shanks, T.

    I first review the status of Digital Sky Surveys. The focus will be on extragalactic surveys with an area of more than 100 deg2. The Sloan Digital Sky Survey is the archetype of such imaging surveys and it is its great success that has prompted great activity in this field. The latest surveys explore wider, fainter and higher resolution and also a longer wavelength range than SDSS. Many of these surveys overlap particularly in the S Hemisphere where we now have Pan-STARRS, DES and the ESO VST surveys, and our aim here is to compare their properties. Since there is no dedicated article on the VST ATLAS in this symposium, we shall especially review the properties of this particular survey. This easily fits onto our other main focus which is to compare overlapping Southern Surveys and see how they best fit with the available NIR imaging data. We conclude that the Southern Hemisphere will soon overtake the North in terms of multiwavelength imaging. However we note that the South has more limited opportunities for spectroscopic follow-up and this weakness will persist during the LSST era. Some new perspectives are offered on this and other aspects of survey astronomy.

  5. Calibration of the DRASTIC ground water vulnerability mapping method

    USGS Publications Warehouse

    Rupert, M.G.

    2001-01-01

    Ground water vulnerability maps developed using the DRASTIC method have been produced in many parts of the world. Comparisons of those maps with actual ground water quality data have shown that the DRASTIC method is typically a poor predictor of ground water contamination. This study significantly improved the effectiveness of a modified DRASTIC ground water vulnerability map by calibrating the point rating schemes to actual ground water quality data by using nonparametric statistical techniques and a geographic information system. Calibration was performed by comparing data on nitrite plus nitrate as nitrogen (NO2 + NO3-N) concentrations in ground water to land-use, soils, and depth to first-encountered ground water data. These comparisons showed clear statistical differences between NO2 + NO3-N concentrations and the various categories. Ground water probability point ratings for NO2 + NO3-N contamination were developed from the results of these comparisons, and a probability map was produced. This ground water probability map was then correlated with an independent set of NO2 + NO3-N data to demonstrate its effectiveness in predicting elevated NO2 + NO3-N concentrations in ground water. This correlation demonstrated that the probability map was effective, but a vulnerability map produced with the uncalibrated DRASTIC method in the same area and using the same data layers was not effective. Considerable time and expense have been outlaid to develop ground water vulnerability maps with the DRASTIC method. This study demonstrates a cost-effective method to improve and verify the effectiveness of ground water vulnerability maps.

  6. Simulation of ground motion using the stochastic method

    USGS Publications Warehouse

    Boore, D.M.

    2003-01-01

    A simple and powerful method for simulating ground motions is to combine parametric or functional descriptions of the ground motion's amplitude spectrum with a random phase spectrum modified such that the motion is distributed over a duration related to the earthquake magnitude and to the distance from the source. This method of simulating ground motions often goes by the name "the stochastic method." It is particularly useful for simulating the higher-frequency ground motions of most interest to engineers (generally, f>0.1 Hz), and it is widely used to predict ground motions for regions of the world in which recordings of motion from potentially damaging earthquakes are not available. This simple method has been successful in matching a variety of ground-motion measures for earthquakes with seismic moments spanning more than 12 orders of magnitude and in diverse tectonic environments. One of the essential characteristics of the method is that it distills what is known about the various factors affecting ground motions (source, path, and site) into simple functional forms. This provides a means by which the results of the rigorous studies reported in other papers in this volume can be incorporated into practical predictions of ground motion.

  7. Complementing Gaia from the ground. The DANCe survey

    NASA Astrophysics Data System (ADS)

    Bouy, H.; Bertin, E.; Sarro, L. M.; Moraux, E.; Barrado, D.; Cuillandre, J. C.; Bouvier, J.; Berihuete, A.; Wright, N.; Beletsky, Y.; Brandner, W.; Olivares, J.

    The DANCe survey aims at complementing Gaia by providing proper motion measurements with a comparable accuracy 4 magnitudes fainter. These measurements are used to identify sub-stellar members of young nearby clusters and associations down the planetary mass regime.

  8. 40 CFR 141.401 - Sanitary surveys for ground water systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: (1) Source, (2) Treatment, (3) Distribution system, (4) Finished water storage, (5) Pumps, pump... Sanitary surveys for ground water systems. (a) Ground water systems must provide the State, at the State's..., maintenance, and monitoring compliance of a public water system to evaluate the adequacy of the system,...

  9. 40 CFR 141.401 - Sanitary surveys for ground water systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: (1) Source, (2) Treatment, (3) Distribution system, (4) Finished water storage, (5) Pumps, pump... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Sanitary surveys for ground water...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

  10. 30 CFR 75.703-1 - Approved method of grounding.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved method of grounding. 75.703-1 Section 75.703-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.703-1 Approved...

  11. 30 CFR 75.703-1 - Approved method of grounding.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved method of grounding. 75.703-1 Section 75.703-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.703-1 Approved...

  12. 30 CFR 75.703-1 - Approved method of grounding.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Approved method of grounding. 75.703-1 Section 75.703-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.703-1 Approved...

  13. Methods of extending signatures and training without ground information. [data processing, pattern recognition

    NASA Technical Reports Server (NTRS)

    Henderson, R. G.; Thomas, G. S.; Nalepka, R. F.

    1975-01-01

    Methods of performing signature extension, using LANDSAT-1 data, are explored. The emphasis is on improving the performance and cost-effectiveness of large area wheat surveys. Two methods were developed: ASC, and MASC. Two methods, Ratio, and RADIFF, previously used with aircraft data were adapted to and tested on LANDSAT-1 data. An investigation into the sources and nature of between scene data variations was included. Initial investigations into the selection of training fields without in situ ground truth were undertaken.

  14. 76 FR 38203 - Proposed Information Collection; North American Woodcock Singing Ground Survey

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-29

    ... migratory bird populations. The North American Woodcock Singing Ground Survey is an essential part of the... Survey AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice; request for comments. SUMMARY: We (U....gov (e-mail). SUPPLEMENTARY INFORMATION: I. Abstract The Migratory Bird Treaty Act (16 U.S.C....

  15. Research opportunities in interdisciplinary ground-water science in the U.S. Geological Survey

    USGS Publications Warehouse

    Sanford, W.E.; Caine, J.S.; Wilcox, D.A.; McWreath, H.C.; Nicholas, J.R.

    2006-01-01

    This report is written for the scientifically literate reader but is not limited to those who are involved in ground-water science. The report is intended to encourage U.S. Geological Survey scientists to develop a sense of excitement about ground-water science in the agency, to inform scientists about existing and potential ground-water science opportunities, and to engage scientists and managers in interdisciplinary discussions and collaboration. The report is intended for use by U.S. Geological Survey and Department of the Interior management to formulate long-term ground-water science programs and to continue sustained support of ground-water monitoring and research, some of which may not have an immediate impact. Finally, the report can be used to communicate the U.S. Geological Survey's vision of ground-water science to Congress, partners, other agencies, and the research community at large with the goals of enhancing collaborative opportunities, sharing information, and maintaining dialogue regarding the directions of U.S. Geological Survey ground-water science.

  16. A Survey of Patch Methods

    NASA Technical Reports Server (NTRS)

    Barnhill, R. E.

    1985-01-01

    Patch methods are someshow a response to the fact that surface geometry is local, that is, only small parts of a surface are created at a time. The two categories of patches, transfinite patches and finite dimensional patches are examined and a discussion of trivariate patches is presented.

  17. Comparison of helicopter and ground surveys for North American elk Cervus elaphus and mule deer Odocoileus hemionus population composition

    USGS Publications Warehouse

    Bender, L.C.; Myers, W.L.; Gould, W.R.

    2003-01-01

    Both ground and helicopter surveys are commonly used to collect sex and age composition data for ungulates. Little attention has been paid, however, to whether data collected by each technique are similar. We compared helicopter and ground composition data for both elk Cervus elaphus and mule deer Odocoileus hemionus across a variety of habitats in the state of Washington, USA. We found that ground and helicopter counts differed (P's < 0.002) consistently in male age structure estimates for elk, and that the two survey methods differed in estimates of adult sex ratios for mule deer (P = 0.023). Counts from helicopters provided larger sample sizes, tended to be more consistent annually in their results, and were corroborated by other demographic studies of the test populations. We conclude that helicopter and ground surveys differ for male age structure and perhaps male:female ratios, but are similar for young:female ratios. Managers should maintain a standardized technique using the same survey vehicle for trend analysis of composition data.

  18. Survey of fracture toughness test methods

    NASA Technical Reports Server (NTRS)

    Brown, W. F., Jr.; Jones, M. H.; Srawley, J. E.

    1968-01-01

    Comprehensive survey presents current methods of fracture toughness testing that are based on linear elastic fracture mechanics. General principles of the basic two dimensional crack stress field model are discussed in relation to real three dimensional specimens. Methods of test instrumentation and procedure are described.

  19. Trachoma survey methods: a literature review

    PubMed Central

    Reacher, Mark; Matthews, Fiona; Brayne, Carol; Emerson, Paul

    2009-01-01

    Abstract Reliable population-based prevalence data are essential for planning, monitoring and evaluating trachoma control programmes and understanding the scale of the problem, yet they are not currently available for 22 out of 56 trachoma-endemic countries. Three survey methods have been advocated for trachoma: cluster random sampling (CRS); trachoma rapid assessment (TRA); and acceptance sampling trachoma rapid assessment (ASTRA). Our review highlights the benefits of CRS being simple, efficient, repeatable and giving population-based prevalence estimates of all signs of trachoma. There are limitations to TRA, which include: non-representative sampling; does not estimate prevalence; and lacks consistency and accuracy. ASTRA advocates small sample sizes but it is relatively complex, may result in imprecise prevalence estimates and does not estimate cicatricial signs of trachoma. We conclude that CRS should therefore remain the “gold” standard for trachoma surveys. However, among the CRS surveys reviewed, we also found several methodological deficiencies of sample-size calculations, standardization of trachoma graders, reporting of confidence intervals of prevalence estimates, variability of age groups for presentation of age-specific prevalence, and lack of estimation of district prevalence estimates. Properly conducted surveys will be crucial if the objective of global elimination of blinding trachoma is to be charted and realized. Harmonization of survey methods will enhance the conduct and comparability of trachoma surveys needed for reliable mapping of prevalence within endemic countries. Consistent with WHO recommendations, we advocate for continued use of CRS as the survey design of choice for trachoma control programmes and propose ways of improving future surveys based on this method. PMID:19274367

  20. Comparison of helicopter and ground surveys of waterfowl broods in southern Ontario

    USGS Publications Warehouse

    Gabor, T.S.; Longcore, J.R.; Murkin, H.R.; Arnason, A.N.

    2000-01-01

    Managers often employ aerial survey information to manage waterfowl. Results of surveys by helicopter and from elevated platforms were compared to determine the accuracy of helicopters to detect waterfowl broods on beaver ponds in southern Ontario in 1996 and 1997. Fewer broods were detected from the helicopter than by observers in elevated platforms at wetland margins. When broods were detected by helicopter crews, >90% were correctly enumerated and >80% were correctly aged. A second helicopter survey, the day following the first survey, did not change the Visibility Correction Factor (VCF) substantially (1.79 vs. 1.53). Data from the 2 helicopter surveys combined (without ground counts) resulted in greater VCFs (2.17) than when a single helicopter survey and ground count was used (VCF = 1.79). In general, VCFs for most waterfowl broods were lower in forested or closed (emergent and scrub-shrub) wetland habitats than on open wetlands. When multiple broods were present on a wetland, sightability of the additional broods (second, third, etc.) was lower for the helicopter crew than ground crew. Surveys by helicopter are likely most useful to develop indices for waterfowl broods of diver species in large inaccessible areas. If accurate information is required on dabbler brood densities, age, and number of ducklings, quiet observation by crews in elevated platforms should be used.

  1. GROUND WATER PURGING AND SAMPLING METHODS: HISTORY VS. HYSTERIA

    EPA Science Inventory

    It has been over 10 years since the low-flow ground water purging and sampling method was initially reported in the literature. The method grew from the recognition that well purging was necessary to collect representative samples, bailers could not achieve well purging, and high...

  2. Tectonic influences on ground water quality: insight from complementary methods.

    PubMed

    Earman, Sam; McPherson, Brian J O L; Phillips, Fred M; Ralser, Steve; Herrin, James M; Broska, James

    2008-01-01

    A study using multiple techniques provided insight into tectonic influences on ground water systems; the results can help to understand ground water systems in the tectonically active western United States and other parts of the world. Ground water in the San Bernardino Valley (Arizona, United States and Sonora, Mexico) is the main source of water for domestic use, cattle ranching (the primary industry), and the preservation of threatened and endangered species. To improve the understanding of ground water occurrence, movement, and sustainability, an investigation was conducted using a number of complementary methods, including major ion geochemistry, isotope hydrology, analysis of gases dissolved in ground water, aquifer testing, geophysics, and an examination of surface and subsurface geology. By combining information from multiple lines of investigation, a more complete picture of the basin hydrogeology was assembled than would have been possible using fewer methods. The results show that the hydrogeology of the San Bernardino Valley is markedly different than that of its four neighboring basins in the United States. The differences include water quality, chemical evolution, storage, and residence time. The differences result from the locally unique geology of the San Bernardino Valley, which is due to the presence of a magmatically active accommodation zone (a zone separating two regions of normal faults with opposite dips). The geological differences and the resultant hydrological differences between the San Bernardino Valley and its neighboring basins may serve as a model for the distinctive nature of chemical evolution of ground water in other basins with locally distinct tectonic histories. PMID:18194326

  3. A survey of aftbody flow prediction methods

    NASA Technical Reports Server (NTRS)

    Putnam, L. E.; Mace, J.

    1981-01-01

    A survey of computational methods used in the calculation of nozzle aftbody flows is presented. One class of methods reviewed are those which patch together solutions for the inviscid, boundary layer, and plume flow regions. The second class of methods reviewed are those which computationally solve the Navier Stokes equations over nozzle aftbodies with jet exhaust flow. Computed results from the methods are compared with experiment. Advantages and disadvantages of the various methods are discussed along with opportunities for further development of these methods.

  4. Survey on large scale system control methods

    NASA Technical Reports Server (NTRS)

    Mercadal, Mathieu

    1987-01-01

    The problem inherent to large scale systems such as power network, communication network and economic or ecological systems were studied. The increase in size and flexibility of future spacecraft has put those dynamical systems into the category of large scale systems, and tools specific to the class of large systems are being sought to design control systems that can guarantee more stability and better performance. Among several survey papers, reference was found to a thorough investigation on decentralized control methods. Especially helpful was the classification made of the different existing approaches to deal with large scale systems. A very similar classification is used, even though the papers surveyed are somehow different from the ones reviewed in other papers. Special attention is brought to the applicability of the existing methods to controlling large mechanical systems like large space structures. Some recent developments are added to this survey.

  5. A Survey of Methods and Materials.

    ERIC Educational Resources Information Center

    Gillis, Candida; And Others

    Designed to assess and describe the nature and frequency of teaching methods, activities, and materials used in secondary school English courses, this survey consists of 14 questions related to teaching objectives, activities, and materials, each followed by a list of possible responses. Teachers are asked to select a course, and to circle for…

  6. Identification of School Bullies by Survey Methods

    ERIC Educational Resources Information Center

    Cole, Joanna C. M.; Cornell, Dewey G.; Sheras, Peter

    2006-01-01

    How can middle school counselors identify bullies? This study compared two methods of identifying bullies in a sample of 386 middle school students. A peer nomination survey identified many more bullies than did student self-report. Moreover, self-reported and peer nominated bullies differed in their types of bullying behaviors, level of general…

  7. Repeat Microgravity Surveys for Estimating Ground-Water Storage Change, Recharge, and Specific Yield

    NASA Astrophysics Data System (ADS)

    Pool, D. R.

    2005-12-01

    Repeat microgravity surveys are being used in arid and semiarid regions to better define ground-water budgets and estimate specific yield. Repeated measurements at single stations or networks of stations are differenced to determine gravity change. Gravity change across a network of stations is integrated to estimate change in total mass and ground-water storage. Calculations are based on the assumption that there are no significant non-ground-water sources of mass change, such as movement of magma. Specific yield values can be estimated at observation-well sites where water-level and gravity changes are correlated. Ground-water budget components of inflow (recharge), outflow, and storage change are commonly uncertain. Rarely is any one component completely defined by measurement. Only outflow at discrete locations, such as wells and streams, can readily be measured. Inflow is difficult to measure because it is normally dispersed across large areas and occurs episodically. Storage change is normally calculated as a residual of outflow and inflow, and includes all of the uncertainties the other components. Ground-water budgets in heavily developed arid and semiarid basins are commonly dominated by storage change. Gravity methods can be used to estimate change, often leaving a single unknown, recharge, that can be estimated as a residual of measured or estimated outflow and storage change. Four types of gravity instruments are currently being used to measure changes in the distribution of mass on the Earth including: absolute meters, relative meters, super-conducting meters, and satellites. Modern absolute meters use lasers and precise clocks to measure the rate of fall of a mass in a vacuum. Relative meters use a very sensitive spring to measure differences in the force of gravity among sites. Super-conducting meters monitor the strength of a magnetic field necessary to levitate a mass against the changing gravity field. Variations in satellite orbits are also a

  8. Exoplanets -New Results from Space and Ground-based Surveys

    NASA Astrophysics Data System (ADS)

    Udry, Stephane

    The exploration of the outer solar system and in particular of the giant planets and their environments is an on-going process with the Cassini spacecraft currently around Saturn, the Juno mission to Jupiter preparing to depart and two large future space missions planned to launch in the 2020-2025 time frame for the Jupiter system and its satellites (Europa and Ganymede) on the one hand, and the Saturnian system and Titan on the other hand [1,2]. Titan, Saturn's largest satellite, is the only other object in our Solar system to possess an extensive nitrogen atmosphere, host to an active organic chemistry, based on the interaction of N2 with methane (CH4). Following the Voyager flyby in 1980, Titan has been intensely studied from the ground-based large telescopes (such as the Keck or the VLT) and by artificial satellites (such as the Infrared Space Observatory and the Hubble Space Telescope) for the past three decades. Prior to Cassini-Huygens, Titan's atmospheric composition was thus known to us from the Voyager missions and also through the explorations by the ISO. Our perception of Titan had thus greatly been enhanced accordingly, but many questions remained as to the nature of the haze surrounding the satellite and the composition of the surface. The recent revelations by the Cassini-Huygens mission have managed to surprise us with many discoveries [3-8] and have yet to reveal more of the interesting aspects of the satellite. The Cassini-Huygens mission to the Saturnian system has been an extraordinary success for the planetary community since the Saturn-Orbit-Insertion (SOI) in July 2004 and again the very successful probe descent and landing of Huygens on January 14, 2005. One of its main targets was Titan. Titan was revealed to be a complex world more like the Earth than any other: it has a dense mostly nitrogen atmosphere and active climate and meteorological cycles where the working fluid, methane, behaves under Titan conditions the way that water does on

  9. A survey of modal synthesis methods.

    NASA Technical Reports Server (NTRS)

    Hart, G. C.; Hurty, W. C.; Collins, J. D.

    1971-01-01

    Several modal synthesis procedures for the dynamic analysis of largy composite structural systems are surveyed. The matrix formulation of the free-free modal synthesis procedures is presented. Also given are schematic flow charts of the analysis procedure used in three prominent methods. The advantages and disadvantages of several modal synthesis methods for different classes of structural problems are presented in order to enable the engineer to select the best procedure for his particular type of problem.

  10. Survey of emissivity measurement by radiometric methods.

    PubMed

    Honner, M; Honnerová, P

    2015-02-01

    A survey of the state of the art in the field of spectral directional emissivity measurements by using radiometric methods is presented. Individual quantity types such as spectral, band, or total emissivity are defined. Principles of emissivity measurement by various methods (direct and indirect, and calorimetric and radiometric) are discussed. The paper is focused on direct radiometric methods. An overview of experimental setups is provided, including the design of individual parts such as the applied reference sources of radiation, systems of sample clamping and heating, detection systems, methods for the determination of surface temperature, and procedures for emissivity evaluation. PMID:25967774

  11. The Constant Comparative Analysis Method Outside of Grounded Theory

    ERIC Educational Resources Information Center

    Fram, Sheila M.

    2013-01-01

    This commentary addresses the gap in the literature regarding discussion of the legitimate use of Constant Comparative Analysis Method (CCA) outside of Grounded Theory. The purpose is to show the strength of using CCA to maintain the emic perspective and how theoretical frameworks can maintain the etic perspective throughout the analysis. My…

  12. 30 CFR 77.703-1 - Approved methods of grounding.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved methods of grounding. 77.703-1 Section 77.703-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF...

  13. Ground-penetrating radar and electromagnetic surveys at the Monroe Crossroads battlefield site, Fort Bragg, North Carolina

    USGS Publications Warehouse

    Kessler, Richard; Strain, R.E.; Marlowe, J. I., II; Currin, K.B.

    1996-01-01

    A ground-penetrating radar survey was conducted at the Monroe Crossroads Battlefield site at Fort Bragg, North Carolina, to determine possible locations of subsurface archaeological features. An electromagnetic survey also was conducted at the site to verify and augment the ground-penetrating radar data. The surveys were conducted over a 67,200-square-foot grid with a grid point spacing of 20 feet. During the ground-penetrating radar survey, 87 subsurface anomalies were detected based on visual inspection of the field records. These anomalies were flagged in the field as they appeared on the ground-penetrating radar records and were located by a land survey. The electromagnetic survey produced two significant readings at ground-penetrating radar anomaly locations. The National Park Service excavated 44 of the 87 anomaly locations at the Civil War battlefield site. Four of these excavations produced significant archaeological features, including one at an abandoned well.

  14. Constrained Path Quantum Monte Carlo Method for Fermion Ground States

    NASA Astrophysics Data System (ADS)

    Zhang, Shiwei; Carlson, J.; Gubernatis, J. E.

    1995-05-01

    We propose a new quantum Monte Carlo algorithm to compute fermion ground-state properties. The ground state is projected from an initial wave function by a branching random walk in an over-complete basis space of Slater determinants. By constraining the determinants according to a trial wave function \\|ΨT>, we remove the exponential decay of signal-to-noise ratio characteristic of the sign problem. The method is variational and is exact if \\|ΨT> is exact. We report results on the two-dimensional Hubbard model up to size 16×16, for various electron fillings and interaction strengths.

  15. Status of ground-water modeling in the U.S. Geological Survey

    USGS Publications Warehouse

    Appel, Charles A.; Bredehoeft, J.D.

    1976-01-01

    The U.S. Geological Survey is active in the development and use of models for the analysis of various types of ground-water problems. Types of problems for which models have been, or are being, developed include: (1) ground-water flow in saturated or partially unsaturated materials, (2) land subsidence resulting from ground-water extraction, (3) flow in coupled ground water-stream systems, (4) coupling of rainfall-runoff basin models with soil moisture accounting and aquifer flow models, (5) interaction of economic and hydrologic considerations, (6) predicting the transport of contaminants in an aquifer, and (7) estimating the effects of proposed development schemes for geothermal systems. The status of modeling activity for various models is reported as being in a developmental, verification, operational, or continued improvement phase. Recently published references that provide useful details on the characteristics of the models are identified. (Woodard-USGS)

  16. Comparison of methods for calibrating AVIRIS data to ground reflectance

    NASA Technical Reports Server (NTRS)

    Clark, Roger N.; Swayze, Gregg; Heidebrecht, Kathy; Goetz, Alexander F. H.; Green, Robert O.

    1993-01-01

    We are comparing three basic methods of calibrating AVIRIS data to ground reflectance: (1) atmospheric radiative transfer models with the solar flux can be used to calibrate AVIRIS radiance data (Specific methods include the University of Colorado CSES ARP and ATREM algorithms); (2) Robert Green's modified MODTRAN and AVIRIS radiance model (This method is similar to 1 but differs in that the solar radiance is bypassed, so any errors in the solar flux are canceled, too); and (3) ground calibration using known sites in the AVIRIS scene. We are using 1992AVIRIS data over Cuprite, Nevada, and Blackhawk Island, Wisconsin, as our test scenes. Both these sites have extensive field measurements. The Cuprite site had a very clear atmosphere, thus path radiance was dominated by Rayleigh scattering with little or no flux beyond 1 micron. The Blackhawk site has more aerosols, with significant path radiance flux beyond 2 micron.

  17. Ground penetrating radar results at the Box Canyon Site - 1996 survey as part of infiltration test

    SciTech Connect

    Peterson, J.E. Jr.; Williams, K.H.

    1997-08-01

    This data report presents a discussion of the borehole radar tomography experiment conducted at Box Canyon, Idaho. Discussion concentrates on the survey methodology, data acquisition procedures, and the resulting tomographic images and interpretations. The entire geophysics field effort for FY96 centered around the collection of the borehole radar data within the inclined boreholes R1, R2, R3, and R4 before, during, and after the ponded infiltration experiment. The well pairs R1-R2, R2-R4, and R3-R4 comprised the bulk of the field survey; however, additional data were collected between vertical boreholes within and around the infiltration basin. The intent of the inclined boreholes was to allow access beneath the infiltration basin and to enhance the ability of the radar method to image both vertical and horizontal features where flow may dominate. This data report will concentrate on the inclined borehole data and the resulting tomograms. The borehole radar method is one in which modified ground penetrating radar antennas are lowered into boreholes and high frequency electromagnetic signals are transmitted through subsurface material to a receiving antenna. The transmitted signals may be represented as multiple raypaths crossing through the zone of interest. If sufficient raypaths are recorded, a tomographic image may be obtained through computer processing. The data normally recorded are signal amplitude versus time. The information extracted from such data includes the following: (a) the transit time which depends on the wave velocity, (b) the amplitude which depends on the wave attenuation, the dispersion which indicates a change in velocity and attenuation with frequency.

  18. Constrained path Monte Carlo method for fermion ground states

    SciTech Connect

    Zhang, S. |; Carlson, J.; Gubernatis, J.E.

    1997-03-01

    We describe and discuss a recently proposed quantum Monte Carlo algorithm to compute the ground-state properties of various systems of interacting fermions. In this method, the ground state is projected from an initial wave function by a branching random walk in an overcomplete basis of Slater determinants. By constraining the determinants according to a trial wave function {vert_bar}{psi}{sub T}{r_angle}, we remove the exponential decay of signal-to-noise ratio characteristic of the sign problem. The method is variational and is exact if {vert_bar}{psi}{sub T}{r_angle} is exact. We illustrate the method by describing in detail its implementation for the two-dimensional one-band Hubbard model. We show results for lattice sizes up to 16{times}16 and for various electron fillings and interaction strengths. With simple single-determinant wave functions as {vert_bar}{psi}{sub T}{r_angle}, the method yields accurate (often to within a few percent) estimates of the ground-state energy as well as correlation functions, such as those for electron pairing. We conclude by discussing possible extensions of the algorithm. {copyright} {ital 1997} {ital The American Physical Society}

  19. Constrained path Monte Carlo method for fermion ground states

    NASA Astrophysics Data System (ADS)

    Zhang, Shiwei; Carlson, J.; Gubernatis, J. E.

    1997-03-01

    We describe and discuss a recently proposed quantum Monte Carlo algorithm to compute the ground-state properties of various systems of interacting fermions. In this method, the ground state is projected from an initial wave function by a branching random walk in an overcomplete basis of Slater determinants. By constraining the determinants according to a trial wave function \\|ψT>, we remove the exponential decay of signal-to-noise ratio characteristic of the sign problem. The method is variational and is exact if \\|ψT> is exact. We illustrate the method by describing in detail its implementation for the two-dimensional one-band Hubbard model. We show results for lattice sizes up to 16×16 and for various electron fillings and interaction strengths. With simple single-determinant wave functions as \\|ψT>, the method yields accurate (often to within a few percent) estimates of the ground-state energy as well as correlation functions, such as those for electron pairing. We conclude by discussing possible extensions of the algorithm.

  20. Biodiversity and agriculture in dynamic landscapes: Integrating ground and remotely-sensed baseline surveys.

    PubMed

    Gillison, Andrew N; Asner, Gregory P; Fernandes, Erick C M; Mafalacusser, Jacinto; Banze, Aurélio; Izidine, Samira; da Fonseca, Ambrósio R; Pacate, Hermenegildo

    2016-07-15

    Sustainable biodiversity and land management require a cost-effective means of forecasting landscape response to environmental change. Conventional species-based, regional biodiversity assessments are rarely adequate for policy planning and decision making. We show how new ground and remotely-sensed survey methods can be coordinated to help elucidate and predict relationships between biodiversity, land use and soil properties along complex biophysical gradients that typify many similar landscapes worldwide. In the lower Zambezi valley, Mozambique we used environmental, gradient-directed transects (gradsects) to sample vascular plant species, plant functional types, vegetation structure, soil properties and land-use characteristics. Soil fertility indices were derived using novel multidimensional scaling of soil properties. To facilitate spatial analysis, we applied a probabilistic remote sensing approach, analyzing Landsat 7 satellite imagery to map photosynthetically active and inactive vegetation and bare soil along each gradsect. Despite the relatively low sample number, we found highly significant correlations between single and combined sets of specific plant, soil and remotely sensed variables that permitted testable spatial projections of biodiversity and soil fertility across the regional land-use mosaic. This integrative and rapid approach provides a low-cost, high-return and readily transferable methodology that permits the ready identification of testable biodiversity indicators for adaptive management of biodiversity and potential agricultural productivity. PMID:27064732

  1. New method for lightning location using optical ground wire

    NASA Astrophysics Data System (ADS)

    Qin, Zhaoyu; Cheng, Zhaogu; Zhang, Zhiping; Zhu, Jianqiang; Li, Feng

    2006-12-01

    A new technology of lightning location is described, which is based on detecting the state of polarization (SOP) fluctuation of the laser light in the optic ground wire (OPGW). Compared with the conventional lightning location method, the new method is more accurate, more stable, and cheaper. Theories of Stokes parameters and Poincare sphere are introduced to analyze the SOP at the lightning strike point. It can be concluded that although the initial points of SOP on the Poincare sphere are random, the SOP fluctuation generated by lightning strike can still be accurately identified by detecting the velocity of polarization motion. A new algorithm to quantify the velocity is also introduced.

  2. A method for reducing ground reflection effects from acoustic measurements

    NASA Technical Reports Server (NTRS)

    Noerager, J. A.; Rice, E. J.; Feiler, C. E.

    1972-01-01

    The method involved placing foam blocks on the ground between sound source and receiver in an approximation of the wedges in an anechoic chamber. The tests were performed out of doors as a function of the receiver height and source-receiver separation distance. The spacing between blocks and the extent of ground covered were varied to estimate the optimum placement and minimum amount of foam treatment needed. Base-line tests without foam were also performed. It was found that the foam treatment reduced the amplitude of the peaks and valleys in the sound pressure spectra substantially. The foam was least effective at low frequency, especially for the low receiver height and for large source-receiver distances. Results from the base-line tests were compared with theoretically predicted results. These base-line test results were in reasonable agreement with those from theory.

  3. MODFLOW-2005 : the U.S. Geological Survey modular ground-water model--the ground-water flow process

    USGS Publications Warehouse

    Harbaugh, Arlen W.

    2005-01-01

    This report presents MODFLOW-2005, which is a new version of the finite-difference ground-water model commonly called MODFLOW. Ground-water flow is simulated using a block-centered finite-difference approach. Layers can be simulated as confined or unconfined. Flow associated with external stresses, such as wells, areal recharge, evapotranspiration, drains, and rivers, also can be simulated. The report includes detailed explanations of physical and mathematical concepts on which the model is based, an explanation of how those concepts are incorporated in the modular structure of the computer program, instructions for using the model, and details of the computer code. The modular structure consists of a MAIN Program and a series of highly independent subroutines. The subroutines are grouped into 'packages.' Each package deals with a specific feature of the hydrologic system that is to be simulated, such as flow from rivers or flow into drains, or with a specific method of solving the set of simultaneous equations resulting from the finite-difference method. Several solution methods are incorporated, including the Preconditioned Conjugate-Gradient method. The division of the program into packages permits the user to examine specific hydrologic features of the model independently. This also facilitates development of additional capabilities because new packages can be added to the program without modifying the existing packages. The input and output systems of the computer program also are designed to permit maximum flexibility. The program is designed to allow other capabilities, such as transport and optimization, to be incorporated, but this report is limited to describing the ground-water flow capability. The program is written in Fortran 90 and will run without modification on most computers that have a Fortran 90 compiler.

  4. A ground moving target emergency tracking method for catastrophe rescue

    NASA Astrophysics Data System (ADS)

    Zhou, X.; Li, D.; Li, G.

    2014-11-01

    In recent years, great disasters happen now and then. Disaster management test the emergency operation ability of the government and society all over the world. Immediately after the occurrence of a great disaster (e.g., earthquake), a massive nationwide rescue and relief operation need to be kicked off instantly. In order to improve the organizations efficiency of the emergency rescue, the organizers need to take charge of the information of the rescuer teams, including the real time location, the equipment with the team, the technical skills of the rescuers, and so on. One of the key factors for the success of emergency operations is the real time location of the rescuers dynamically. Real time tracking methods are used to track the professional rescuer teams now. But volunteers' participation play more and more important roles in great disasters. However, real time tracking of the volunteers will cause many problems, e.g., privacy leakage, expensive data consumption, etc. These problems may reduce the enthusiasm of volunteers' participation for catastrophe rescue. In fact, the great disaster is just small probability event, it is not necessary to track the volunteers (even rescuer teams) every time every day. In order to solve this problem, a ground moving target emergency tracking method for catastrophe rescue is presented in this paper. In this method, the handheld devices using GPS technology to provide the location of the users, e.g., smart phone, is used as the positioning equipment; an emergency tracking information database including the ID of the ground moving target (including the rescuer teams and volunteers), the communication number of the handheld devices with the moving target, and the usually living region, etc., is built in advance by registration; when catastrophe happens, the ground moving targets that living close to the disaster area will be filtered by the usually living region; then the activation short message will be sent to the selected

  5. Exploring the diversity of exoplanet atmospheres from the ground with the ACCESS Survey

    NASA Astrophysics Data System (ADS)

    Espinoza, Nestor; Jordan, Andres; Apai, Daniel; Lopez-Morales, Mercedes; Rackham, Benjamin; Lewis, Nikole K.; Fraine, Jonathan; Diaz-Pérez, Ryan; Rodler, Florian; Wells, Robert; Osip, David

    2015-12-01

    One of the most exciting possibilities enabled by transiting exoplanets is to measure their atmospheric properties through the technique of transmission spectroscopy: the variation of the transit depth as a function of wavelength due to starlight interacting with the atmosphere of the exoplanet. Motivated by the need of optical transmission spectra of exoplanets, we recently launched the Arizona-CfA-Católica Exoplanet Spectroscopy Survey (ACCESS), which aims at studying the atmospheres of ~20 exoplanets ranging from super-Earths to hot-Jupiters in the entire optical atmospheric window using ground-based facilities from both northern and southern hemispheres. In this talk, I will present the survey and its first results using Magellan/IMACS data, focusing on the lessons learned and future prospects of the survey.

  6. Collaborative study of a method for the extraction of light filth from ground mace and ground caraway seed.

    PubMed

    Thrasher, J J

    1976-07-01

    A new method has been developed for the extraction of light filth from ground mace and ground caraway seed. The method uses a 2-step chloroform-isopropanol pretreatment followed by separation of the light filth from 40% isopropanol with mineral oil. The collaborative study resulted in clean filter papers with more reproducible recoveries of light filth elements than the official first action method, 44.116 (b). The method has been adopted as official first action. PMID:939749

  7. Geological and seismological survey for new design-basis earthquake ground motion of Kashiwazaki-Kariwa NPS

    NASA Astrophysics Data System (ADS)

    Takao, M.; Mizutani, H.

    2009-05-01

    viewpoint of geological structure, however we have decided to take into consideration simultaneous movement of the three faults which is 91km long in seismic design as a case of uncertainty. In the sea area, we conducted seismic reflection prospecting with sonic wave in the area stretching for about 140km along the coastline and 50km in the direction of perpendicular to the coastline. When we analyze the seismic profiles, we evaluated the activities of faults and foldings carefully on the basis of the way of thinking of 'fault-related-fault' because the sedimentary layers in the offing of Niigata prefecture are very thick and the geological structures are characterized by foldings. As a result of the seismic reflection survey and analyses, we assess that five active faults (foldings) to be taken into consideration to seismic design in the sea area and we evaluated that the F-B fault of 36km will have the largest impact on the KKNPS. [Seismological survey] As a result of analyses of the geological survey, data from NCOE and data from 2004 Chuetsu Earthquake, it became clear that there are factors that intensifies seismic motions in this area. For each of the two selected earthquake sources, namely NPWBFZ and F-B fault, we calculated seismic ground motions on the free surface of the base stratum as the design-basis ground motion (DBGM) Ss, using both empirical and numerical ground motion evaluation method. PGA value of DBGM is 2,300Gal for unit 1 to 4 located in the southern part of the KKNPS and 1,050Gal for unit 5 to 7 in the northern part of the site.

  8. Ground-penetrating radar surveying in support of archeological site investigations

    NASA Astrophysics Data System (ADS)

    Baker, Jesse A.; Anderson, Neil L.; Pilles, Peter J.

    1997-12-01

    In April and July of 1996, ground-penetrating radar (GPR) surveys were conducted in support of archeological investigations at Flagstaff, Arizona and Sebastian, Florida, respectively. A GSSI SIR System 8 radar unit with a 500-MHz monostatic antenna was used for both surveys. The Flagstaff, Arizona survey was conducted at Elden Pueblo Ruins. The site is located in a coniferous forest and characterized by a myriad of surficial and subsurface features. Surficial features consisted mostly of pottery shards and the remnants of rock walled structures. The subsurface features consist mostly of rock lined pits, stone walls, and grave sites covered by a soil layer of variable thickness. The soil is derived from volcanic clastics and the underlying Kaibab Limestone bedrock. GPR profiles were acquired across various locations, some of which had been previously excavated and backfilled by archeologists. The main objectives were to determine the utility of the GPR technique with respect to locating subsurface features of archeological interest, determine the optimum field parameters in the area, and direct further field work. The Sebastian, Florida survey was conducted along the Atlantic coastline. Data were acquired along five beaches and one coastal sand dune. The beaches and dunes of the area are composed of a medium to coarse grained sand, containing quartz grains and carbonates. The principle objective of the Sebastian, Florida survey was to locate wreckage from a Spanish treasure fleet. A secondary objective was to determine the utility of GPR in a near shore marine environment.

  9. Modified Universal Design Survey: Enhancing Operability of Launch Vehicle Ground Crew Worksites

    NASA Technical Reports Server (NTRS)

    Blume, Jennifer L.

    2010-01-01

    Operability is a driving requirement for next generation space launch vehicles. Launch site ground operations include numerous operator tasks to prepare the vehicle for launch or to perform preflight maintenance. Ensuring that components requiring operator interaction at the launch site are designed for optimal human use is a high priority for operability. To promote operability, a Design Quality Evaluation Survey based on Universal Design framework was developed to support Human Factors Engineering (HFE) evaluation for NASA s launch vehicles. Universal Design per se is not a priority for launch vehicle processing however; applying principles of Universal Design will increase the probability of an error free and efficient design which promotes operability. The Design Quality Evaluation Survey incorporates and tailors the seven Universal Design Principles and adds new measures for Safety and Efficiency. Adapting an approach proven to measure Universal Design Performance in Product, each principle is associated with multiple performance measures which are rated with the degree to which the statement is true. The Design Quality Evaluation Survey was employed for several launch vehicle ground processing worksite analyses. The tool was found to be most useful for comparative judgments as opposed to an assessment of a single design option. It provided a useful piece of additional data when assessing possible operator interfaces or worksites for operability.

  10. Assessment of some important factors affecting the singing-ground survey

    USGS Publications Warehouse

    Tautin, J.

    1982-01-01

    A brief history of the procedures used to analyze singing-ground survey data is outlined. Some weaknesses associated with the analytical procedures are discussed, and preliminary results of efforts to improve the procedures are presented. The most significant finding to date is that counts made by new observers need not be omitted when calculating an index of the woodcock population. Also, the distribution of woodcock heard singing, with respect to time after sunset, affirms the appropriateness of recommended starting times for counting woodcock. Woodcock count data fit the negative binomial probability distribution.

  11. Application of ground-penetrating-radar methods in hydrogeologic studies

    USGS Publications Warehouse

    Beres, Milan, Jr.; Haeni, F.P.

    1991-01-01

    A ground-penetrating-radar system was used to study selected stratified-drift deposits in Connecticut. Ground-penetrating radar is a surface-geophysical method that depends on the emission, transmission, reflection, and reception of an electromagnetic pulse and can produce continuous high-resolution profiles of the subsurface rapidly and efficiently. Traverse locations on land included a well field in the town of Mansfield, a sand and gravel pit and a farm overlying a potential aquifer in the town of Coventry, and Haddam Meadows State Park in the town of Haddam. Traverse locations on water included the Willimantic River in Coventry and Mansfield Hollow Lake in Mansfield. The penetration depth of the radar signal ranged from about 20 feet in fine-grained glaciolacustrine sediments to about 70 feet in coarse sand and gravel. Some land records in coarse-grained sediments show a distinct, continuous reflection from the water table about 5 to 11 feet below land surface. Parallel reflectors on the records are interpreted as fine-grained sediments. Hummocky or chaotic reflectors are interpreted as cross-bedded or coarse-grained sediments. Other features observed on some of the radar records include the till and bedrock surface. Records collected on water had distinct water-bottom multiples (more than one reflection) and diffraction patterns from boulders. The interpretation of the radar records, which required little or no processing, was verified by using lithologic logs from test holes located along some of the land traverses and near the water traverses.

  12. Signature of hydrothermal alteration in ground-magnetic surveys at Yellowstone National Park

    NASA Astrophysics Data System (ADS)

    Bouligand, C.; Glen, J. M.; McPhee, D. K.

    2011-12-01

    Yellowstone National Park (YNP) hosts a very large hydrothermal system with over 10,000 thermal features. Although hydrothermal alteration in YNP has been extensively studied with field observations, remote-sensing imagery, and core drilling, the volume and geometry of hydrothermal systems at depth remain poorly constrained. Magnetic surveys can help to investigate buried hydrothermal alteration as demonstrated by the high-resolution aeromagnetic survey of YNP (Finn and Morgan, J. Volcanol. Geotherm. Res., 115, 207-231, 2002). Results of this survey show that magnetic lows extend over and beyond areas of hydrothermal activity. This suggests large volumes of buried demagnetized rocks due to hydrothermal alteration of the volcanic substratum. Although the interpretation of magnetic anomalies is non-unique, Finn and Morgan (2002) used these magnetic lows to estimate a minimum volume of buried altered rock assuming complete demagnetization of the substratum. This aeromagnetic survey was of relatively high resolution (flight line spacing < 500 m and flight elevation <350 m above ground), but it was insufficient for detailed mapping of individual thermal areas. In order to obtain a closer look at several areas, we performed ground-based magnetic surveys within YNP using a cesium-vapor magnetometer along 4-5 km long transects crossing four thermal areas (Norris Geyser Basin, Lower Geyser Basin, Lone Star Geyser Basin, and Smoke Jumper Hot-springs). We also performed a detailed survey over an area of about 800 m x 500 m around Lone Star Geyser. We also collected gravity data to help characterize the subsurface geologic structures and performed magnetic susceptibility, magnetic remanence, and density measurements on rock samples collected in the field and from drill cores collected in 1967-1968 to characterize physical properties of fresh and altered geologic units. The long magnetic transects show that magnetic anomalies are damped in altered areas suggesting a significant

  13. Method of drilling with fluid comprising peanut hulls ground to a powder

    SciTech Connect

    Forrest, G.T.

    1992-02-11

    This patent describes a method of carrying out operations wherein a fluid is circulated in a well extending into the ground. It comprises: taking peanut hulls which have been ground to a powder form, adding the ground peanut hulls to a fluid, and circulating the fluid, with the ground peanut hulls added thereto, in the well.

  14. Method and apparatus for injecting particulate media into the ground

    DOEpatents

    Dwyer, Brian P.; Dwyer, Stephen F.; Vigil, Francine S.; Stewart, Willis E.

    2004-12-28

    An improved method and apparatus for injecting particulate media into the ground for constructing underground permeable reactive barriers, which are used for environmental remediation of subsurface contaminated soil and water. A media injector sub-assembly attached to a triple wall drill string pipe sprays a mixture of active particulate media suspended in a carrier fluid radially outwards from the sub-assembly, at the same time that a mixing fluid is sprayed radially outwards. The media spray intersects the mixing spray at a relatively close distance from the point of injection, which entrains the particulate media into the mixing spray and ensures a uniform and deep dispersion of the active media in the surrounding soil. The media injector sub-assembly can optionally include channels for supplying compressed air to an attached down-the-hole hammer drive assembly for use during drilling.

  15. A comparison of vibration damping methods for ground based telescopes

    NASA Astrophysics Data System (ADS)

    Anderson, Eric H.; Glaese, Roger M.; Neill, Douglas

    2008-07-01

    Vibration is becoming a more important element in design of telescope structures as these structures become larger and more compliant and include higher bandwidth actuation systems. This paper describes vibration damping methods available for current and future implementation and compares their effectiveness for a model of the Large Synoptic Survey Telescope (LSST), a structure that is actually stiffer than most large telescopes. Although facility and mount design, structural stiffening and occasionally vibration isolation have been adequate in telescopes built to date, vibration damping offers a mass-efficient means of reducing vibration response, whether the vibration results from external wind disturbances, telescope slewing, or other internal disturbances from translating or rotating components. The paper presents several damping techniques including constrained layer viscoelastics, viscous and magnetorheological (MR) fluid devices, passive and active piezoelectric dampers, tuned mass dampers (vibration absorbers) and active resonant dampers. Basic architectures and practical implementation considerations are discussed and expected performance is assessed using a finite element model of the LSST. With a goal of reducing settling time during the telescope's surveys, and considering practicalities of integration with the telescope structure, two damping methods were identified as most appropriate: passive tuned mass dampers and active electromagnetic resonant dampers.

  16. Multidisciplinary eHealth Survey Evaluation Methods

    ERIC Educational Resources Information Center

    Karras, Bryant T.; Tufano, James T.

    2006-01-01

    This paper describes the development process of an evaluation framework for describing and comparing web survey tools. We believe that this approach will help shape the design, development, deployment, and evaluation of population-based health interventions. A conceptual framework for describing and evaluating web survey systems will enable the…

  17. Thermal Methods for Investigating Ground-Water Recharge

    USGS Publications Warehouse

    Blasch, Kyle W.; Constantz, Jim; Stonestrom, David A.

    2007-01-01

    Recharge of aquifers within arid and semiarid environments is defined as the downward flux of water across the regional water table. The introduction of recharging water at the land surface can occur at discreet locations, such as in stream channels, or be distributed over the landscape, such as across broad interarroyo areas within an alluvial ground-water basin. The occurrence of recharge at discreet locations is referred to as focused recharge, whereas the occurrence of recharge over broad regions is referred to as diffuse recharge. The primary interest of this appendix is focused recharge, but regardless of the type of recharge, estimation of downward fluxes is essential to its quantification. Like chemical tracers, heat can come from natural sources or be intentionally introduced to infer transport properties and aquifer recharge. The admission and redistribution of heat from natural processes such as insolation, infiltration, and geothermal activity can be used to quantify subsurface flow regimes. Heat is well suited as a ground-water tracer because it provides a naturally present dynamic signal and is relatively harmless over a useful range of induced perturbations. Thermal methods have proven valuable for recharge investigations for several reasons. First, theoretical descriptions of coupled water-and-heat transport are available for the hydrologic processes most often encountered in practice. These include land-surface mechanisms such as radiant heating from the sun, radiant cooling into space, and evapotranspiration, in addition to the advective and conductive mechanisms that usually dominate at depth. Second, temperature is theoretically well defined and readily measured. Third, thermal methods for depths ranging from the land surface to depths of hundreds of meters are based on similar physical principles. Fourth, numerical codes for simulating heat and water transport have become increasingly reliable and widely available. Direct measurement of water

  18. Airborne Gravity Survey and Ground Gravity in Afghanistan: A Website for Distribution of Data

    USGS Publications Warehouse

    Abraham, Jared D.; Anderson, Eric D.; Drenth, Benjamin J.; Finn, Carol A.; Kucks, Robert P.; Lindsay, Charles R.; Phillips, Jeffrey D.; Sweeney, Ronald E.

    2008-01-01

    Afghanistan?s geologic setting suggests significant natural resource potential. Although important mineral deposits and petroleum resources have been identified, much of the country?s potential remains unknown. Airborne geophysical surveys are a well- accepted and cost-effective method for remotely obtaining information of the geological setting of an area. A regional airborne geophysical survey was proposed due to the security situation and the large areas of Afghanistan that have not been covered using geophysical exploration methods. Acting upon the request of the Islamic Republic of Afghanistan Ministry of Mines, the U.S. Geological Survey contracted with the U.S. Naval Research Laboratory to jointly conduct an airborne geophysical and remote sensing survey of Afghanistan. Data collected during this survey will provide basic information for mineral and petroleum exploration studies that are important for the economic development of Afghanistan. Additionally, use of these data is broadly applicable in the assessment of water resources and natural hazards, the inventory and planning of civil infrastructure and agricultural resources, and the construction of detailed maps. The U.S. Geological Survey is currently working in cooperation with the U.S. Agency of International Development to conduct resource assessments of the country of Afghanistan for mineral, energy, coal, and water resources, and to assess geologic hazards. These geophysical and remote sensing data will be used directly in the resource and hazard assessments.

  19. Geophysical Methods for Investigating Ground-Water Recharge

    USGS Publications Warehouse

    Ferre, Ty P.A.; Binley, Andrew M.; Blasch, Kyle W.; Callegary, James B.; Crawford, Steven M.; Fink, James B.; Flint, Alan L.; Flint, Lorraine E.; Hoffmann, John P.; Izbicki, John A.; Levitt, Marc T.; Pool, Donald R.; Scanlon, Bridget R.

    2007-01-01

    While numerical modeling has revolutionized our understanding of basin-scale hydrologic processes, such models rely almost exclusively on traditional measurements?rainfall, streamflow, and water-table elevations?for calibration and testing. Model calibration provides initial estimates of ground-water recharge. Calibrated models are important yet crude tools for addressing questions about the spatial and temporal distribution of recharge. An inverse approach to recharge estimation is taken of necessity, due to inherent difficulties in making direct measurements of flow across the water table. Difficulties arise because recharging fluxes are typically small, even in humid regions, and because the location of the water table changes with time. Deep water tables in arid and semiarid regions make recharge monitoring especially difficult. Nevertheless, recharge monitoring must advance in order to improve assessments of ground-water recharge. Improved characterization of basin-scale recharge is critical for informed water-resources management. Difficulties in directly measuring recharge have prompted many efforts to develop indirect methods. The mass-balance approach of estimating recharge as the residual of generally much larger terms has persisted despite the use of increasing complex and finely gridded large-scale hydrologic models. Geophysical data pertaining to recharge rates, timing, and patterns have the potential to substantially improve modeling efforts by providing information on boundary conditions, by constraining model inputs, by testing simplifying assumptions, and by identifying the spatial and temporal resolutions needed to predict recharge to a specified tolerance in space and in time. Moreover, under certain conditions, geophysical measurements can yield direct estimates of recharge rates or changes in water storage, largely eliminating the need for indirect measures of recharge. This appendix presents an overview of physically based, geophysical methods

  20. Digitized data from ground geophysical surveys in Afghanistan: A website for distribution of data

    USGS Publications Warehouse

    Polster, Sarah W.; Drenth, Benjamin J.

    2011-01-01

    This document describes the process of digitization of a 1974 report on geophysical work undertaken by Soviet geophysicists in southern and eastern Afghanistan. These data, uncovered in Afghanistan, represent magnetic and electrical ground surveys for which locations are not well defined. Due to lack of location information, these surveys were georeferenced using the cities, rivers, and surrounding geology found on the maps used to plot survey locations. A geologic map found in the Soviet report contains profile lines that correspond to the geophysical maps, allowing these data to be georeferenced. The profiles correspond to sets of resistivity, chargeabiliy, and magnetic data. Some datasets were presented as graphs and needed to be gridded into a useable image. Only the vertical component of the magnetic field was collected, so conversion to total field anomaly was necessary. The magnetic data were collected in either gammas or milliorstead, both of which required conversion to standard SI units. To be useful to modern studies, the datasets and images contained in this report have been digitized, georeferenced, and in some cases converted into computer-ready formats.

  1. The Use of National Survey Data in Teaching Methods of Survey Research.

    ERIC Educational Resources Information Center

    Egginton, Everett

    A description is given of a college course in survey research and attitudinal measurement offered by the School of Education at the University of Louisville. The graduate level course focuses on the principles of social research; survey research methods; and data analysis, interpretation, and application. National survey data are used to teach all…

  2. Optimising UAV topographic surveys processed with structure-from-motion: Ground control quality, quantity and bundle adjustment

    NASA Astrophysics Data System (ADS)

    James, Mike R.; Robson, Stuart; d'Oleire-Oltmanns, Sebastian; Niethammer, Uwe

    2016-04-01

    Structure-from-motion (SfM) algorithms are greatly facilitating the production of detailed topographic models based on images collected by unmanned aerial vehicles (UAVs). However, SfM-based software does not generally provide the rigorous photogrammetric analysis required to fully understand survey quality. Consequently, error related to problems in control point data or the distribution of control points can remain undiscovered. Even if these errors are not large in magnitude, they can be systematic, and thus have strong implications for the use of products such as digital elevation models (DEMs) and orthophotos. Here, we develop a Monte Carlo approach to (1) improve the accuracy of products when SfM-based processing is used and (2) reduce the associated field effort by identifying suitable lower density deployments of ground control points. The method highlights over-parameterisation during camera self-calibration and provides enhanced insight into control point performance when rigorous error metrics are not available. Processing was implemented using commonly-used SfM-based software (Agisoft PhotoScan), which we augment with semi-automated and automated GCPs image measurement. We apply the Monte Carlo method to two contrasting case studies - an erosion gully survey (Taurodont, Morocco) carried out with an fixed-wing UAV, and an active landslide survey (Super-Sauze, France), acquired using a manually controlled quadcopter. The results highlight the differences in the control requirements for the two sites, and we explore the implications for future surveys. We illustrate DEM sensitivity to critical processing parameters and show how the use of appropriate parameter values increases DEM repeatability and reduces the spatial variability of error due to processing artefacts.

  3. A STUDY ON APPLICABILITY OF GROUND RESPONSE ACCELERATION METHOD TO DEEP VERTICAL UNDERGROUND STRUCTURES

    NASA Astrophysics Data System (ADS)

    Matsumoto, Mai; Shiba, Yukio; Watanabe, Kazuaki

    This paper discusses the applicability of ground response acceleration method to seismic analysis for deep vertical underground structures. To examine the applicability, an analysis of relationships between response of ground and the shaft was conducted. It was found from the analysis that vertical axial stress of the shaft was not correspond with shear stress of ground. Accordingly, it was concluded that the axial stress was not evaluated correctly by the existing method. Therefore, to extend the applicability of the method, ground responses correlated with the axial stress were analyzed and a new method using these ground responses was proposed.

  4. NATIONAL SURFACE WATER SURVEY, WESTERN LAKE SURVEY (PHASE 1 - SYNOPTIC CHEMISTRY) ANALYTICAL METHODS MANUAL

    EPA Science Inventory

    The Analytical Methods Manual for the Western Lake Survey - Phase I is a supplement to the Analytical Methods Manual for the Eastern Lake Survey Phase I. The supplement provides a general description of the analytical methods that are used by the field laboratories and by the ana...

  5. Method for Ground-to-Satellite Laser Calibration System

    NASA Technical Reports Server (NTRS)

    Lukashin, Constantine (Inventor); Wielicki, Bruce A. (Inventor)

    2015-01-01

    The present invention comprises an approach for calibrating the sensitivity to polarization, optics degradation, spectral and stray light response functions of instruments on orbit. The concept is based on using an accurate ground-based laser system, Ground-to-Space Laser Calibration (GSLC), transmitting laser light to instrument on orbit during nighttime substantially clear-sky conditions. To minimize atmospheric contribution to the calibration uncertainty the calibration cycles should be performed in short time intervals, and all required measurements are designed to be relative. The calibration cycles involve ground operations with laser beam polarization and wavelength changes.

  6. Method for Ground-to-Space Laser Calibration System

    NASA Technical Reports Server (NTRS)

    Lukashin, Constantine (Inventor); Wielicki, Bruce A. (Inventor)

    2014-01-01

    The present invention comprises an approach for calibrating the sensitivity to polarization, optics degradation, spectral and stray light response functions of instruments on orbit. The concept is based on using an accurate ground-based laser system, Ground-to-Space Laser Calibration (GSLC), transmitting laser light to instrument on orbit during nighttime substantially clear-sky conditions. To minimize atmospheric contribution to the calibration uncertainty the calibration cycles should be performed in short time intervals, and all required measurements are designed to be relative. The calibration cycles involve ground operations with laser beam polarization and wavelength changes.

  7. Apparatus and method for grounding compressed fuel fueling operator

    DOEpatents

    Cohen, Joseph Perry; Farese, David John; Xu, Jianguo

    2002-06-11

    A safety system for grounding an operator at a fueling station prior to removing a fuel fill nozzle from a fuel tank upon completion of a fuel filling operation is provided which includes a fuel tank port in communication with the fuel tank for receiving and retaining the nozzle during the fuel filling operation and a grounding device adjacent to the fuel tank port which includes a grounding switch having a contact member that receives physical contact by the operator and where physical contact of the contact member activates the grounding switch. A releasable interlock is included that provides a lock position wherein the nozzle is locked into the port upon insertion of the nozzle into the port and a release position wherein the nozzle is releasable from the port upon completion of the fuel filling operation and after physical contact of the contact member is accomplished.

  8. Topics in Research Methods: Survey Sampling.

    ERIC Educational Resources Information Center

    Cook, Tony; Rushton, Brian S.

    1984-01-01

    Reviews a computer-assisted learning package (available from CONDUIT) which introduces survey and sampling techniques by pretending that the user is a pollster asking one of six questions of a more or less political nature. Documentation and performance are rated fair while ease of use is considered excellent. (JN)

  9. NCES Handbook of Survey Methods: Technical Report.

    ERIC Educational Resources Information Center

    Thurgood, Lori; Walter, Elizabeth; Carter, George; Henn, Susan; Huang, Gary; Nooter, Daniel; Smith, Wray; Cash, R. William; Salvucci, Sameena; Seastrom, Marilyn; Phan, Tai; Cohen, Michael

    This handbook presents current explanations of how each survey program of the National Center for Education Statistics (NCES) obtains and prepared the data it publishes. The handbook aims to provide users of NCES data with the most current information necessary to evaluate the suitability of the statistics for their needs, with a focus on the…

  10. Ecological survey of M-Field, Edgewood Area Aberdeen Proving Ground, Maryland

    SciTech Connect

    Downs, J.L.; Eberhardt, L.E.; Fitzner, R.E.; Rogers, L.E.

    1991-12-01

    An ecological survey was conducted on M-Field, at the Edgewood Area, Aberdeen Proving Ground, Maryland. M-Field is used routinely to test army smokes and obscurants, including brass flakes, carbon fibers, and fog oils. The field has been used for testing purposes for the past 40 years, but little documented history is available. Under current environmental regulations, the test field must be assessed periodically to document the presence or potential use of the area by threatened and endangered species. The M-Field area is approximately 370 acres and is part of the US Army's Edgewood Area at Aberdeen Proving Ground in Harford County, Maryland. The grass-covered field is primarily lowlands with elevations from about 1.0 to 8 m above sea level, and several buildings and structures are present on the field. The ecological assessment of M-Field was conducted in three stages, beginning with a preliminary site visit in May to assess sampling requirements. Two field site visits were made June 3--7, and August 12--15, 1991, to identify the biota existing on the site. Data were gathered on vegetation, small mammals, invertebrates, birds, large mammals, amphibians, and reptiles.

  11. Ecological survey of M-Field, Edgewood Area Aberdeen Proving Ground, Maryland

    SciTech Connect

    Downs, J.L.; Eberhardt, L.E.; Fitzner, R.E.; Rogers, L.E.

    1991-12-01

    An ecological survey was conducted on M-Field, at the Edgewood Area, Aberdeen Proving Ground, Maryland. M-Field is used routinely to test army smokes and obscurants, including brass flakes, carbon fibers, and fog oils. The field has been used for testing purposes for the past 40 years, but little documented history is available. Under current environmental regulations, the test field must be assessed periodically to document the presence or potential use of the area by threatened and endangered species. The M-Field area is approximately 370 acres and is part of the US Army`s Edgewood Area at Aberdeen Proving Ground in Harford County, Maryland. The grass-covered field is primarily lowlands with elevations from about 1.0 to 8 m above sea level, and several buildings and structures are present on the field. The ecological assessment of M-Field was conducted in three stages, beginning with a preliminary site visit in May to assess sampling requirements. Two field site visits were made June 3--7, and August 12--15, 1991, to identify the biota existing on the site. Data were gathered on vegetation, small mammals, invertebrates, birds, large mammals, amphibians, and reptiles.

  12. A ground-penetrating radar survey for archaeological investigations in an urban area (Lecce, Italy)

    NASA Astrophysics Data System (ADS)

    Basile, V.; Carrozzo, M. T.; Negri, S.; Nuzzo, L.; Quarta, T.; Villani, A. V.

    2000-04-01

    A ground-penetrating radar (GPR) survey, using mostly a 500 MHz antenna, was carried out in an urban area (Lecce, Italy) to obtain a detailed characterization of the most superficial layers, where presumably archaeological structures are buried, and to quickly identify anomalous zones for excavation. In the area, the presence of remnants of a historical Franciscan friary (built in 1432 and pulled down in 1971) and, probably, of more ancient (Roman and/or Messapic) features was expected. The geological setting (mainly wet calcarenite named "Pietra Leccese") was not the most favourable for the application of GPR methodology because of an expected high attenuation of electromagnetic energy. The low penetration depth of the signal, not exceeding 1 m and even using a 100 MHz antenna, made it possible to obtain information only between the ground level and the top of the calcarenitic basement. Data recorded along parallel profiles, 1 m spaced, prevented the clear identification of the walls of the historical building constructed in "Pietra Leccese" blocks, because of the weak contrast in the electromagnetic parameters with respect to the hosting material. On the other hand, the analysis of the radar sections allowed for identification and reconstruction of the shape and extension of a barrel-vault cavity, subsequently confirmed by archaeological excavations. Time slice representations were used as a tool to locate other features including modern-day urban utilities and the planimetric development of the barrel-vault cavity.

  13. An Innovative, Effective and Cost Effective Survey Method Using a Survey-Check Response Format

    PubMed Central

    Feil, Edward G.; Severson, Herbert; Taylor, Ted; Boles, Shawn; Albert, David A.; Blair, Jason

    2007-01-01

    Maximizing the response rate to surveys involves thoughtful choices about survey design, sampling and collection methods. This paper describes an innovative survey method, to provide immediate reinforcement for responding and to minimize the response cost. This method involves using a questionnaire printed as checks on security (anti-fraud) paper with questions and responses separated using a perforated tear off section. Once a participant completes the survey, the response area is detached from the questions, thus protecting the confidentiality of the subject, and the check is returned via the banking system. This report describes the survey-check methodology, the survey flow process, and the results from four research studies which have used this method. These studies include (1) a technology accessibility survey of parents with children enrolled in a low-income preschool program; (2) a parent report of their child’s behavior used as screening criteria for inclusion in a computer-mediated parent education project; (3) a follow-up questionnaire as part of a longitudinal study of child behavior, covering home and classroom interventions, and service utilization, and; (4) a survey of dentists in support of efforts to recruit them to participate in a randomized control trial of tobacco cessation in dental offices. The results of using this method show great improvement in response rates over traditionally administered surveys for three of the four reported studies. Results are discussed in terms of future applications of this method, limitations, and potential cost savings. PMID:17180473

  14. An innovative, effective and cost effective survey method using a survey-check response format.

    PubMed

    Feil, Edward G; Severson, Herbert; Taylor, Ted K; Boles, Shawn; Albert, David A; Blair, Jason

    2007-06-01

    Maximizing the response rate to surveys involves thoughtful choices about survey design, sampling and collection methods. This paper describes an innovative survey method, to provide immediate reinforcement for responding and to minimize the response cost. This method involves using a questionnaire printed as checks on security (anti-fraud) paper with questions and responses separated using a perforated tear off section. Once a participant completes the survey, the response area is detached from the questions, thus protecting the confidentiality of the subject, and the check is returned via the banking system. This report describes the survey-check methodology, the survey flow process, and the results from four research studies which have used this method. These studies include (1) a technology accessibility survey of parents with children enrolled in a low-income preschool program; (2) a parent report of their child's behavior used as screening criteria for inclusion in a computer-mediated parent education project; (3) a follow-up questionnaire as part of a longitudinal study of child behavior, covering home and classroom interventions, and service utilization, and; (4) a survey of dentists in support of efforts to recruit them to participate in a randomized control trial of tobacco cessation in dental offices. The results of using this method show great improvement in response rates over traditionally administered surveys for three of the four reported studies. Results are discussed in terms of future applications of this method, limitations, and potential cost savings. PMID:17180473

  15. 40 CFR 141.402 - Ground water source microbial monitoring and analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Ground water source microbial monitoring and analytical methods. 141.402 Section 141.402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.402 Ground water source...

  16. 40 CFR 141.402 - Ground water source microbial monitoring and analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Ground water source microbial monitoring and analytical methods. 141.402 Section 141.402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.402 Ground water source...

  17. Application of a Modified Universal Design Survey for Evaluation of Ares 1 Ground Crew Worksites

    NASA Technical Reports Server (NTRS)

    Blume, Jennifer L.

    2010-01-01

    Operability is a driving requirement for NASA's Ares 1 launch vehicle. Launch site ground operations include several operator tasks to prepare the vehicle for launch or to perform maintenance. Ensuring that components requiring operator interaction at the launch site are designed for optimal human use is a high priority for operability. To support design evaluation, the Ares 1 Upper Stage (US) element Human Factors Engineering (HFE) group developed a survey based on the Universal Design approach. Universal Design is a process to create products that can be used effectively by as many people as possible. Universal Design per se is not a priority for Ares 1 because launch vehicle processing is a specialized skill and not akin to a consumer product that should be used by all people of all abilities. However, applying principles of Universal Design will increase the probability of an error free and efficient design which is a priority for Ares 1. The Design Quality Evaluation Survey centers on the following seven principles: (1) Equitable use, (2) Flexibility in use, (3) Simple and intuitive use, (4) Perceptible information, (5) Tolerance for error, (6) Low physical effort, (7) Size and space for approach and use. Each principle is associated with multiple evaluation criteria which were rated with the degree to which the statement is true. All statements are phrased in the utmost positive, or the design goal so that the degree to which judgments tend toward "completely agree" directly reflects the degree to which the design is good. The Design Quality Evaluation Survey was employed for several US analyses. The tool was found to be most useful for comparative judgments as opposed to an assessment of a single design option. It provided a useful piece of additional data when assessing possible operator interfaces or worksites for operability

  18. Verifying a computational method for predicting extreme ground motion

    USGS Publications Warehouse

    Harris, R.A.; Barall, M.; Andrews, D.J.; Duan, B.; Ma, S.; Dunham, E.M.; Gabriel, A.-A.; Kaneko, Y.; Kase, Y.; Aagaard, B.T.; Oglesby, D.D.; Ampuero, J.-P.; Hanks, T.C.; Abrahamson, N.

    2011-01-01

    In situations where seismological data is rare or nonexistent, computer simulations may be used to predict ground motions caused by future earthquakes. This is particularly practical in the case of extreme ground motions, where engineers of special buildings may need to design for an event that has not been historically observed but which may occur in the far-distant future. Once the simulations have been performed, however, they still need to be tested. The SCEC-USGS dynamic rupture code verification exercise provides a testing mechanism for simulations that involve spontaneous earthquake rupture. We have performed this examination for the specific computer code that was used to predict maximum possible ground motion near Yucca Mountain. Our SCEC-USGS group exercises have demonstrated that the specific computer code that was used for the Yucca Mountain simulations produces similar results to those produced by other computer codes when tackling the same science problem. We also found that the 3D ground motion simulations produced smaller ground motions than the 2D simulations.

  19. Underwater sediment-contact radiation survey method

    SciTech Connect

    Lee, D.R.; St. Aubin, M.; Welch, S.J. )

    1991-11-01

    The authors are striving to produce a practical system for mapping lateral distributions in gamma activity on submerged sediments. This is in response to the need for quality control and interpretation of data obtainable by sediment sampling and analyses near nuclear utilities. A prototype gamma probe has been constructed and tested. The prototype is essentially a background survey meter packaged in a 53-cm-long {times} 5.4-cm-diam waterproof vehicle. This usage-shaped vehicle is connected to a cable for towing in contact with bottom sediments of lakes, rivers, and coastal waters. This vehicle, or sediment probe as it is called, was initially developed for measuring sediment electrical conductances, a parameter that can be used to locate underwater areas of groundwater and contaminant upwelling. During towing, the probe does not roll or twist around its longitudinal axis by more than 10 deg, so that sensors, which have been fixed within the vehicle, can be oriented to look up, down, or sideways. In over 450 lin-km of underwater survey, only a single sediment probe has been irretrievably snagged on sunken rocks or other debris. Work in the Ottawa River near the Chalk River Laboratories has shown good agreement among point measurements of river sediment with continuous measurements using the moving probe.

  20. 30 CFR 75.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... a borehole casing having low resistance to earth; (b) A solid connection to metal waterlines having low resistance to earth; (c) A solid connection to a grounding conductor, other than the neutral... ensures that there is no difference in potential between such metallic enclosures and the earth....

  1. 30 CFR 75.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... a borehole casing having low resistance to earth; (b) A solid connection to metal waterlines having low resistance to earth; (c) A solid connection to a grounding conductor, other than the neutral... ensures that there is no difference in potential between such metallic enclosures and the earth....

  2. 30 CFR 75.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... a borehole casing having low resistance to earth; (b) A solid connection to metal waterlines having low resistance to earth; (c) A solid connection to a grounding conductor, other than the neutral... ensures that there is no difference in potential between such metallic enclosures and the earth....

  3. 30 CFR 75.700-1 - Approved methods of grounding.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... a borehole casing having low resistance to earth; (b) A solid connection to metal waterlines having low resistance to earth; (c) A solid connection to a grounding conductor, other than the neutral... ensures that there is no difference in potential between such metallic enclosures and the earth....

  4. A quality-assurance plan for district ground-water activities of the U.S. Geological Survey

    USGS Publications Warehouse

    Brunett, J.O.; Barber, N.L.; Burns, A.W.; Fogelman, R.P.; Gillies, D.C.; Lidwin, R.A.; Mack, Thomas J.

    1997-01-01

    As the Nation's principal earth-science information agency, the U.S. Geological Survey (USGS) is depended upon to collect data of the highest quality. This document provides the framework for collecting, analyzing and reporting ground-water data that are quality assured and quality controlled.

  5. Guidelines for Coding and Entering Ground-Water Data into the Ground-Water Site Inventory Database Version 4.6, U.S. Geological Survey, Washington Water Science Center

    USGS Publications Warehouse

    Lane, R.C.

    2007-01-01

    This report establishes and documents the procedures used by the U.S. Geological Survey, Washington Water Science Center, to code and enter ground-water data into the Ground-Water Site Inventory database of the U.S. Geological Survey's Ground Water Site Inventory System. These guidelines are consistent with Version 4.6 of the system, but will be updated as each new version becomes available.

  6. Do singing-ground surveys reflect american woodcock abundance in the western Great Lakes region?

    USGS Publications Warehouse

    Matthew R. Nelson; Andersen, David E.

    2013-01-01

    The Singing-ground Survey (SGS) is the primary monitoring tool used to assess population status and trends of American woodcock (Scolopax minor). Like most broad-scale surveys, the SGS cannot be directly validated because there are no independent estimates of abundance of displaying male American woodcock at an appropriate spatial scale. Furthermore, because locations of individual SGS routes have generally remained stationary since the SGS was standardized in 1968, it is not known whether routes adequately represent the landscapes they were intended to represent. To indirectly validate the SGS, we evaluated whether 1) counts of displaying male American woodcock on SGS routes related to land-cover types known to be related to American woodcock abundance, 2) changes in counts of displaying male American woodcock through time were related to changes in land cover along SGS routes, and 3) land-cover type composition along SGS routes was similar to land-cover type composition of the surrounding landscape. In Wisconsin and Minnesota, USA, counts along SGS routes reflected known American woodcock-habitat relations. Increases in the number of woodcock heard along SGS routes over a 13-year period in Wisconsin were related to increasing amounts of early successional forest, decreasing amounts of mature forest, and increasing dispersion and interspersion of cover types. Finally, the cover types most strongly associated with American woodcock abundance were represented along SGS routes in proportion to their composition of the broader landscape. Taken together, these results suggest that in the western Great Lakes region, the SGS likely provides a reliable tool for monitoring relative abundance and population trends of breeding, male American woodcock.

  7. Correlation of low level ground water contamination and soil gas survey results at a manufacturing site in Connecticut

    SciTech Connect

    Bartley, R.; Viellenave, J.H.; Bedard, P.C.

    1995-06-01

    A large manufacturing facility (14 acre property with 5 acre building) in Connecticut, used for manufacturing and large scale printing since World War II, was investigated to determine the sources and extent of ground water contamination by organics using a combination of soil gas surveying and traditional monitoring well sampling and analysis. The soil gas survey, the PETREX Technology, was used to limit and guide the installation of monitoring wells and allow interpolation between wells. A total of only eleven wells was used to fully define the magnitude and extent of ground water contamination across the entire site, resulting in substantial savings for the investigation of the facility. Linear regression analysis was performed on the soil gas ion responses and ground water concentrations of PCE, TCE, and TCA from the eleven monitoring wells. The ground water concentrations were near the drinking water levels and ranged from Not Detected to 17 ppb for PCE, Not Detected to 18 ppb for TCE, and Not Detected to 124 ppb for TCA. The regression calculations indicate coefficients of correlation (R) between ground water organic contaminant concentrations and soil gas ion responses of +0.93 for PCE, +0.85 for TCE, and +0.82 for TCA. We conclude that, if not influenced by soil contamination, the PETREX soil gas results can be a good predictor of the presence and the general level of an organic contaminant in ground water, and can therefore be a very useful and cost effective guide to drilling and sampling programs.

  8. Magnetic and ground penetrating radar surveys for the research of Medieval settlements in the inland of the Marche Region (Italy)

    NASA Astrophysics Data System (ADS)

    Bavusi, M.; Giocoli, A.; Balasco, M.; Favulli, G.; Moscatelli, U.; Minguzzi, S.; Gnesi, D.; Virgili, S.

    2009-04-01

    This work was carried out in the framework of the R.I.M.E.M. project (Research on Medieval settlements in the inland of the Marche Region, Italy.) leaded by the Universities of Macerata and Udine and having the aim to produce a significant contribution for the comprehension of the settlement process in the Central and Southern Italy during the Late Roman Period and Early Middle Ages. Then, an extensive gradiometric survey were carried out, by using a vapour caesium magnetometer, in the area included amongst the municipal districts of Caldarola, Cessapalombo and San Ginesio, sited in the area closed to Macerata between the valleys of Chienti and Fiastra rivers. Moreover, in the most interesting areas, a 400 MHz 3D ground penetrating radar (GPR)survey was carried out in order to get the precise overlapping with the magnetic method. The Magnetic method is now a standard practice in the archaeological research taken into great consideration for its non-destructivity and quickness and its capability of mapping wide areas in quite a short lapse of time (Bavusi et al., 2008). Moreover the method provides an information well correlable with remote sensing data (Gallo et al, 2008). The GPR method is extremely useful for archaeologists thanks to its non-destructivity and capability of giving real-time and high-resolution data (Basile et al., 2000). Today the effectiveness of this method was improved by powerful 3D visualisation methods as well as 3D space, time or depth slices and iso-amplitude surfaces, too (Nuzzo et al., 2002). The integrations of several geophysical methods are usual (Sambuelli et al.1999, De Domenico et al., 2001; Chianese et al., 2004) particularly when a simple comparison in cross section along the same profiles can be performed. In this work the overlapping between two kinds of data was complicated by different outputs coming from two methods: maps for the magnetic method and cross sections for the GPR one. The 3D survey design for the GPR survey and

  9. A study of methods for lowering aerial environmental survey cost

    NASA Technical Reports Server (NTRS)

    Stansberry, J. R.

    1973-01-01

    The results are presented of a study of methods for lowering the cost of environmental aerial surveys. A wide range of low cost techniques were investigated for possible application to current pressing urban and rural problems. The objective of the study is to establish a definition of the technical problems associated with conducting aerial surveys using various low cost techniques, to conduct a survey of equipment which may be used in low cost systems, and to establish preliminary estimates of cost. A set of candidate systems were selected and described for the environmental survey tasks.

  10. A survey of payload integration methods

    NASA Technical Reports Server (NTRS)

    Engels, R. C.; Harcrow, H. W.

    1981-01-01

    The most prominent payload integration methods are presented and evaluated. The paper outlines the problem and some of the difficulties encountered when analyzing a coupled booster/payload system. Descriptions of both full-scale and short-cut methods are given together with an assessment of their strengths and weaknesses. Finally, an extensive list of references is included.

  11. Methods for the survey and genetic analysis of populations

    DOEpatents

    Ashby, Matthew

    2003-09-02

    The present invention relates to methods for performing surveys of the genetic diversity of a population. The invention also relates to methods for performing genetic analyses of a population. The invention further relates to methods for the creation of databases comprising the survey information and the databases created by these methods. The invention also relates to methods for analyzing the information to correlate the presence of nucleic acid markers with desired parameters in a sample. These methods have application in the fields of geochemical exploration, agriculture, bioremediation, environmental analysis, clinical microbiology, forensic science and medicine.

  12. MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model - User Guide to Modularization Concepts and the Ground-Water Flow Process

    USGS Publications Warehouse

    Harbaugh, Arlen W.; Banta, Edward R.; Hill, Mary C.; McDonald, Michael G.

    2000-01-01

    MODFLOW is a computer program that numerically solves the three-dimensional ground-water flow equation for a porous medium by using a finite-difference method. Although MODFLOW was designed to be easily enhanced, the design was oriented toward additions to the ground-water flow equation. Frequently there is a need to solve additional equations; for example, transport equations and equations for estimating parameter values that produce the closest match between model-calculated heads and flows and measured values. This report documents a new version of MODFLOW, called MODFLOW-2000, which is designed to accommodate the solution of equations in addition to the ground-water flow equation. This report is a user's manual. It contains an overview of the old and added design concepts, documents one new package, and contains input instructions for using the model to solve the ground-water flow equation.

  13. in situ Measures of LED Installations: Results of Air and Ground Surveys

    NASA Astrophysics Data System (ADS)

    Craine, Eric Richard; Craine, Brian L.

    2015-08-01

    Light Emitting Diode (LED) outdoor light fixtures of different types are rapidly proliferating in many communities, particularly in the form of continuous roadway, work, and parking lot lights. These lights offer a wide range of benefits, but many in the astronomical community have expressed various concerns about their impact on local observatory facilities. We have spent several years developing complementary ground-based and aerial techniques of measuring light installations in the field. Unfortunately, large community retrofits of lighting preclude comprehensive measurement of the changes that result unless baseline data have been collected prior to completion of the new installations. Because of the rapidity of conversion to LEDs, it is increasingly difficult to conduct informative before and after surveys. As a point of interest to astronomers, we offer examples of some in situ measurements of LED installations, compare those measurements to results for older light fixtures, and discuss some of the implications for astronomy. These objective data may be helpful in reaching an informed perspective on how LED lights perform in typical settings.

  14. A survey of mixed finite element methods

    NASA Technical Reports Server (NTRS)

    Brezzi, F.

    1987-01-01

    This paper is an introduction to and an overview of mixed finite element methods. It discusses the mixed formulation of certain basic problems in elasticity and hydrodynamics. It also discusses special techniques for solving the discrete problem.

  15. Advanced signal processing method for ground penetrating radar feature detection and enhancement

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Venkatachalam, Anbu Selvam; Huston, Dryver; Xia, Tian

    2014-03-01

    This paper focuses on new signal processing algorithms customized for an air coupled Ultra-Wideband (UWB) Ground Penetrating Radar (GPR) system targeting highway pavements and bridge deck inspections. The GPR hardware consists of a high-voltage pulse generator, a high speed 8 GSps real time data acquisition unit, and a customized field-programmable gate array (FPGA) control element. In comparison to most existing GPR system with low survey speeds, this system can survey at normal highway speed (60 mph) with a high horizontal resolution of up to 10 scans per centimeter. Due to the complexity and uncertainty of subsurface media, the GPR signal processing is important but challenging. In this GPR system, an adaptive GPR signal processing algorithm using Curvelet Transform, 2D high pass filtering and exponential scaling is proposed to alleviate noise and clutter while the subsurface features are preserved and enhanced. First, Curvelet Transform is used to remove the environmental and systematic noises while maintain the range resolution of the B-Scan image. Then, mathematical models for cylinder-shaped object and clutter are built. A two-dimension (2D) filter based on these models removes clutter and enhances the hyperbola feature in a B-Scan image. Finally, an exponential scaling method is applied to compensate the signal attenuation in subsurface materials and to improve the desired signal feature. For performance test and validation, rebar detection experiments and subsurface feature inspection in laboratory and field configurations are performed.

  16. A Novel Method of Enhancing Grounded Theory Memos with Voice Recording

    ERIC Educational Resources Information Center

    Stocker, Rachel; Close, Helen

    2013-01-01

    In this article the authors present the recent discovery of a novel method of supplementing written grounded theory memos with voice recording, the combination of which may provide significant analytical advantages over solely the traditional written method. Memo writing is an essential component of a grounded theory study, however it is often…

  17. A survey of payload integration methods

    NASA Technical Reports Server (NTRS)

    Engels, R. C.; Craig, R. R., Jr.; Harcrow, H. W.

    1984-01-01

    Several full-scale and short-cut methods for analyzing a booster/payload system are presented. Two full-scale techniques are considered: (1) a technique that uses a restrained payload together with a free-booster model, the latter being augmented with residual mass and stiffness correction and (2) a technique that uses a restrained payload and booster model. Both techniques determine the 'modal modes', which require the solution of a system eigenvalue problem; the loads usually are then determined via an acceleration approach. A brief description is given of a number of short-cut methods which are of special interest to Shuttle payload design: structural modification, base drive, and interface impedance methods. Directions for further research and development are suggested.

  18. Optimal filtering methods to structural damage estimation under ground excitation.

    PubMed

    Hsieh, Chien-Shu; Liaw, Der-Cherng; Lin, Tzu-Hsuan

    2013-01-01

    This paper considers the problem of shear building damage estimation subject to earthquake ground excitation using the Kalman filtering approach. The structural damage is assumed to take the form of reduced elemental stiffness. Two damage estimation algorithms are proposed: one is the multiple model approach via the optimal two-stage Kalman estimator (OTSKE), and the other is the robust two-stage Kalman filter (RTSKF), an unbiased minimum-variance filtering approach to determine the locations and extents of the damage stiffness. A numerical example of a six-storey shear plane frame structure subject to base excitation is used to illustrate the usefulness of the proposed results. PMID:24453869

  19. Evaluation of aerial survey methods for Dall's sheep

    USGS Publications Warehouse

    Udevitz, M.S.; Shults, B.S.; Adams, L.G.; Kleckner, C.

    2006-01-01

    Most Dall's sheep (Ovis dalli dalli) population-monitoring efforts use intensive aerial surveys with no attempt to estimate variance or adjust for potential sightability bias. We used radiocollared sheep to assess factors that could affect sightability of Dall's sheep in standard fixed-wing and helicopter surveys and to evaluate feasibility of methods that might account for sightability bias. Work was conducted in conjunction with annual aerial surveys of Dall's sheep in the western Baird Mountains, Alaska, USA, in 2000-2003. Overall sightability was relatively high compared with other aerial wildlife surveys, with 88% of the available, marked sheep detected in our fixed-wing surveys. Total counts from helicopter surveys were not consistently larger than counts from fixed-wing surveys of the same units, and detection probabilities did not differ for the 2 aircraft types. Our results suggest that total counts from helicopter surveys cannot be used to obtain reliable estimates of detection probabilities for fixed-wing surveys. Groups containing radiocollared sheep often changed in size and composition before they could be observed by a second crew in units that were double-surveyed. Double-observer methods that require determination of which groups were detected by each observer will be infeasible unless survey procedures can be modified so that groups remain more stable between observations. Mean group sizes increased during our study period, and our logistic regression sightability model indicated that detection probabilities increased with group size. Mark-resight estimates of annual population sizes were similar to sightability-model estimates, and confidence intervals overlapped broadly. We recommend the sightability-model approach as the most effective and feasible of the alternatives we considered for monitoring Dall's sheep populations.

  20. A Survey of Quantum Lyapunov Control Methods

    PubMed Central

    2013-01-01

    The condition of a quantum Lyapunov-based control which can be well used in a closed quantum system is that the method can make the system convergent but not just stable. In the convergence study of the quantum Lyapunov control, two situations are classified: nondegenerate cases and degenerate cases. For these two situations, respectively, in this paper the target state is divided into four categories: the eigenstate, the mixed state which commutes with the internal Hamiltonian, the superposition state, and the mixed state which does not commute with the internal Hamiltonian. For these four categories, the quantum Lyapunov control methods for the closed quantum systems are summarized and analyzed. Particularly, the convergence of the control system to the different target states is reviewed, and how to make the convergence conditions be satisfied is summarized and analyzed. PMID:23766732

  1. BOREHOLE SENSING METHODS FOR GROUND-WATER INVESTIGATIONS AT HAZARDOUS WASTE SITES

    EPA Science Inventory

    Geophysical methods are becoming a cost effective approach to providing answers to hydrogeologic questions associated with ground-water contamination. Geophysical methods applicable to hazardous waste site investigations can be broken into two categories: surface and subsurface m...

  2. Controlling flexible structures: A survey of methods

    NASA Technical Reports Server (NTRS)

    Benson, Russell A.; Coleman, Edward E.

    1989-01-01

    Most of the presently available control system design techniques applicable to flexible structure problems were developed to design controllers for rigid body systems. Although many of these design methods can be applied to flexible dynamics problems, recently developed techniques may be more suitable for flexible structure controller design. The purpose of this presentation is to examine briefly the peculiarities of the dynamics of flexible structures and to stimulate discussion about top level controller design approaches when designing controllers for flexible structures. Presented here is a suggestion of a set of categories of design methods for designing controllers for flexible structures as well as a discussion of the advantages and disadvantages of each category. No attempt has been made herein to select one category of design techniques as the best for flexible structure controller design. Instead, it is hoped that the structure suggested by these categories will facilitate further discussion on the merits of particular methods that will eventually point to those design techniques suitable for further development.

  3. Survey of assay methods of antivenins

    PubMed Central

    Grasset, E.

    1957-01-01

    In view of the multiplicity of methods used at present for the preparation and assay of antivenins and as a first step towards the international standardization of antivenins, it seemed advisable to make a comparative study of the methods used in the institutes specializing in the production of these sera. With this end in view, the author circulated to the serologists of institutes concerned a detailed questionnaire on the assay methods used for the determination of the neutralization potency of the various types of antivenins prepared under their direction. The information supplied by these institutes is reproduced, in condensed form, in this report and is analysed by the author. The author emphasizes that the great variety in the constitution of venoms necessitates: (1) the use of monovalent standard sera against homologous “test” venoms of high activity and stability; and (2) the establishment, on a regional basis, of standard antivenins corresponding to groups of snakes characterized by venoms of common or closely related antigenic constitution. PMID:13413648

  4. Learning Japanese in America: A Survey of Preferred Teaching Methods.

    ERIC Educational Resources Information Center

    Furuhata, Hamako

    2002-01-01

    Reports a survey of students in eight colleges that their opinions were sought on the teaching methods and learning styles most suited to the learning of Japanese in their own setting. Results show that students favor a mixture of traditional and contemporary methods and have no difficulty with traditional methods of teaching that are no loner…

  5. Correlation of low level ground water contamination and soil gas survey results at a manufacturing site in Connecticut

    SciTech Connect

    Bartley, R.; Viellenave, J.H.; Bedard, P.C.

    1994-12-31

    A large manufacturing facility (14 acre property with 5 acre building) in Connecticut, used for manufacturing and large scale printing since World War II, was investigated to determine the sources and extent of groundwater contamination by organics using a combination of soil gas surveying and traditional monitoring well sampling and analysis. The soil gas survey, the PETREX Technology, was used to limit and guide the installation of monitoring wells and allow interpolation between wells. A total of only eleven wells was used to fully define the magnitude and extent of ground water contamination across the entire site, resulting in substantial savings for the investigation of the facility. Linear regression analysis was performed on the soil and gas ion response and ground water concentrations of PCE, TCE, and TCA from the eleven monitoring wells. The ground water concentrations were near the drinking water levels and ranged from Not Detected to 17 ppb for PCE, Not Detected to 18 ppb for TCE, and Not Detected to 124 ppb for TCA. The regression calculations indicate coefficients of correlation (R) between ground water organic contaminant concentrations and soils gas ion responses of +0.93 for PCE, +0.85 for TCE, and +0.82 for TCA. The authors conclude that, if not influenced by soil contamination, the PETREX soil gas results can be a good predictor of the presence and the general level of an organic contaminant in ground water, and can therefore be a very useful and cost effective guide to drilling and sampling programs.

  6. Evaluation of the U.S. Geological Survey Ground-Water Data-Collection Program in Hawaii, 1992

    USGS Publications Warehouse

    Anthony, Stephen S.

    1997-01-01

    In 1992, the U.S. Geological Survey ground-water data-collection program in the State of Hawaii consisted of 188 wells distributed among the islands of Oahu, Kauai, Maui, Molokai, and Hawaii. Water-level and water-quality (temperature, specific conductance, and chloride concentration) data were collected from observation wells, deep monitoring wells that penetrate the zone of transition between freshwater and saltwater, free-flowing wells, and pumped wells. The objective of the program was to collect sufficient spatial and temporal data to define seasonal and long-term changes in ground-water levels and chloride concentrations induced by natural and human-made stresses for different climatic and hydrogeologic settings. Wells needed to meet this objective can be divided into two types of networks: (1) a water-management network to determine the response of ground-water flow systems to human-induced stresses, such as pumpage, and (2) a baseline network to determine the response of ground-water flow systems to natural stresses for different climatic and hydrogeologic settings. Maps showing the distribution and magnitude of pumpage and the distribution of proposed pumped wells are presented to identify areas in need of water-management networks. Wells in the 1992 U.S. Geological Survey ground-water data-collection program were classified as either water-management or baseline network wells. In addition, locations where additional water-management network wells are needed for water-level and water-quality data were identified.

  7. Survey of methods for soil moisture determination

    NASA Technical Reports Server (NTRS)

    Schmugge, T. J.; Jackson, T. J.; Mckim, H. L.

    1979-01-01

    Existing and proposed methods for soil moisture determination are discussed. These include: (1) in situ investigations including gravimetric, nuclear, and electromagnetic techniques; (2) remote sensing approaches that use the reflected solar, thermal infrared, and microwave portions of the electromagnetic spectrum; and (3) soil physics models that track the behavior of water in the soil in response to meteorological inputs (precipitation) and demands (evapotranspiration). The capacities of these approaches to satisfy various user needs for soil moisture information vary from application to application, but a conceptual scheme for merging these approaches into integrated systems to provide soil moisture information is proposed that has the potential for meeting various application requirements.

  8. [Historical survey of modern reversible contraceptive methods].

    PubMed

    Mbabajende, V

    1986-04-01

    Because of contraception, pregnancy need not be viewed by women as punishment for sexual activity but as a planned and desired event. Most of the contraceptive methods used in developing countries at present were introduced during the 1960s, but use of contraception has a long history and some methods date back to antiquity. Contraceptive pills were already used around 2000 BC in the form of mercury and arsenic tablets. Their effectiveness was questionable. The role of hormones in human reproduction began to be understood only in the early 1900s. The discovery of progesterone in a Mexican iguana in the 1940s permitted production of progesterone on a large scale. Estrogens had been identified around 1930. Human trials of a contraceptive pill beginning in 1956 in Puerto Rico demonstrated that progestins could prevent pregnancy by suppressing ovulation. Later on, estrogen was added to reduce menstrual irregularities. The 1st generation of combined oral contraceptives contained very high levels of hormones associated with high rates of side effects. Numerous formulations with lower hormonal contents became available beginning around 1970 and constitute the principal formulations in use today. A number of long acting hormonal methods based on progestins have been developed, including injectables, some IUDs and vaginal rings, and implants. The 1st commercially available injectable, norethisterone enanthate, did not acquire the wide distribution of medroxyprogesterone acetate, sold as Depo Provera and used to treat various pathological conditions as well as for contraception. The 1st true IUDs were small stones placed within the uteri of camels by nomads to prevent pregnancy during long caravans. An IUD was developed in 1909 by Richter, and the 2 most widely used models before 1960 were the Grafenberg and Ota silver rings. Use of the 2 rings became rare for medical reasons after 1935 despite their efficacy. Safe plastic IUDs which appeared beginning in the early 1960s

  9. Ground penetrating radar surveys over an alluvial DNAPL site, Paducah Gaseous Diffusion Plant, Kentucky

    SciTech Connect

    Carpenter, P.J. |; Doll, W.E.; Phillips, B.E.

    1994-09-01

    Ground penetrating radar (GPR) surveys were used to map shallow sands and gravels which are DNAPL migration pathways at the Paducah Gaseous Diffusion Plant in western Kentucky. The sands and gravels occur as paleochannel deposits, at depths of 17-25 ft, embedded in Pleistocene lacustrine clays. More than 30 GPR profiles were completed over the Drop Test Area (DTA) to map the top and base of the paleochannel deposits, and to assess their lateral continuity. A bistatic radar system was used with antenna frequencies of 25 and 50 MHz. An average velocity of 0.25 ft/ns for silty and clayey materials above the paleochannel deposits was established from radar walkaway tests, profiles over culverts of known depth, and comparison of radar sections with borings. In the south portion of the DTA, strong reflections corresponded to the water table at approximately 9-10 ft, the top of the paleochannel deposits at approximately 18 ft, and to gravel horizons within these deposits. The base of these deposits was not visible on the radar sections. Depth estimates for the top of the paleochannel deposits (from 50 records) were accurate to within 2 ft across the southern portion of the DTA. Continuity of these sands and gravels could not be assessed due to interference from air-wave reflections and lateral changes in signal penetration depth. However, the sands and gravels appear to extend across the entire southern portion of the DTA, at depths as shallow as 17 ft. Ringing, air-wave reflections and diffractions from powerlines, vehicles, well casings, and metal equipment severly degraded GPR profiles in the northern portion of the DTA; depths computed from reflection times (where visible) were accurate to within 4 ft in this area. The paleochannel deposits are deeper to the north and northeast where DNAPL has apparently pooled (DNAPL was not directly imaged by the GPR, however). Existing hydrogeological models of the DTA will be revised.

  10. Health-based screening levels to evaluate U.S. Geological Survey ground water quality data

    USGS Publications Warehouse

    Toccalino, P.L.; Norman, J.E.

    2006-01-01

    Federal and state drinking-water standards and guidelines do not exist for many contaminants analyzed by the U.S. Geological Survey's National Water-Quality Assessment Program, limiting the ability to evaluate the potential human-health relevance of water-quality findings. Health-based screening levels (HBSLs) were developed collaboratively to supplement existing drinking-water standards and guidelines as part of a six-year, multi-agency pilot study. The pilot study focused on ground water samples collected prior to treatment or blending in areas of New Jersey where groundwater is the principal source of drinking water. This article describes how HBSLs were developed and demonstrates the use of HBSLs as a tool for evaluating water-quality data in a human-health context. HBSLs were calculated using standard U.S. Environmental Protection Agency (USEPA) methodologies and toxicity information. New HBSLs were calculated for 12 of 32 contaminants without existing USEPA drinking-water standards or guidelines, increasing the number of unregulated contaminants (those without maximum contaminant levels (MCLs)) with human-health benchmarks. Concentrations of 70 of the 78 detected contaminants with human-health benchmarks were less than MCLs or HBSLs, including all 12 contaminants with new HBSLs, suggesting that most contaminant concentrations were not of potential human-health concern. HBSLs were applied to a state-scale groundwater data set in this study, but HBSLs also may be applied to regional and national evaluations of water-quality data. HBSLs fulfill a critical need for federal, state, and local agencies, water utilities, and others who seek tools for evaluating the occurrence of contaminants without drinking-water standards or guidelines. ?? 2006 Society for Risk Analysis.

  11. The National Criminal Justice Treatment Practices survey: Multilevel survey methods and procedures⋆

    PubMed Central

    Taxman, Faye S.; Young, Douglas W.; Wiersema, Brian; Rhodes, Anne; Mitchell, Suzanne

    2007-01-01

    The National Criminal Justice Treatment Practices (NCJTP) survey provides a comprehensive inquiry into the nature of programs and services provided to adult and juvenile offenders involved in the justice system in the United States. The multilevel survey design covers topics such as the mission and goals of correctional and treatment programs; organizational climate and culture for providing services; organizational capacity and needs; opinions of administrators and staff regarding rehabilitation, punishment, and services provided to offenders; treatment policies and procedures; and working relationships between correctional and other agencies. The methodology generates national estimates of the availability of programs and services for offenders. This article details the methodology and sampling frame for the NCJTP survey, response rates, and survey procedures. Prevalence estimates of juvenile and adult offenders under correctional control are provided with externally validated comparisons to illustrate the veracity of the methodology. Limitations of the survey methods are also discussed. PMID:17383548

  12. Seasonal changes in groundwater storage estimated by absolute ground gravity and MRS surveys in West Africa

    NASA Astrophysics Data System (ADS)

    Favreau, G.; Boucher, M.; Luck, B.; Pfeffer, J.; Genthon, P.; Hinderer, J.

    2009-04-01

    Important and fast groundwater storage changes occur in tropical monsoon regions in response to seasonal rainfall and subsequent surface water redistribution. In West Africa, one main goal of the GHYRAF experiment (Gravity and Hydrology in Africa, 2008-2010) is to compare absolute gravimetric measurements with dense hydrological surveys to better estimate and model water storage changes at various time scales. Magnetic Resonance Sounding (MRS) is a non-invasive geophysical method having a signal directly related to groundwater quantity. In SW Niger, MRS surveys were performed concurrently with gravimetric (FG5) measurements for monitoring seasonal changes in groundwater storage. Water table levels were recorded on a 4-piezometers profile (~500 m) near a temporary pond (area ~2 ha) fed by sandy gullies. The volume of water drained from the pond to the phreatic aquifer was computed to be ~100,000 m3/yr. Large piezometric fluctuations (3-6 m) occurred in response to indirect recharge through the pond during the 2008 rainy season (July-Sept.), with stronger water table fluctuations recorded near the pond. Absolute gravimetric (FG5) measurements were performed at a distance of 150 m from the pond, in order to minimize the influence of 2D effects on gravimetric records. The increase in absolute gravity measured between two dates (July-Sept.) was 8.7 ± 2.6 µGal; for the same period, the measured water table rise was +3.0 m. Considering these values, a first estimate of the groundwater storage increase is 0.2 m, corresponding to a porosity filled up by the water table rise of ~7%. Repeated MRS surveys were performed at the same location for different dates (three soundings in Sept., one in Dec.). The MRS water content was 13%, with little variation in space (±3%) along the piezometric profile. In response to a 3 metres drop in the water table (Sept- Dec), there was no significant recorded change in the MRS water content and/or in the estimated MRS water table depth. MRS

  13. Methods for Bayesian Power Spectrum Inference with Galaxy Surveys

    NASA Astrophysics Data System (ADS)

    Jasche, Jens; Wandelt, Benjamin D.

    2013-12-01

    We derive and implement a full Bayesian large scale structure inference method aiming at precision recovery of the cosmological power spectrum from galaxy redshift surveys. Our approach improves upon previous Bayesian methods by performing a joint inference of the three-dimensional density field, the cosmological power spectrum, luminosity dependent galaxy biases, and corresponding normalizations. We account for all joint and correlated uncertainties between all inferred quantities. Classes of galaxies with different biases are treated as separate subsamples. This method therefore also allows the combined analysis of more than one galaxy survey. In particular, it solves the problem of inferring the power spectrum from galaxy surveys with non-trivial survey geometries by exploring the joint posterior distribution with efficient implementations of multiple block Markov chain and Hybrid Monte Carlo methods. Our Markov sampler achieves high statistical efficiency in low signal-to-noise regimes by using a deterministic reversible jump algorithm. This approach reduces the correlation length of the sampler by several orders of magnitude, turning the otherwise numerically unfeasible problem of joint parameter exploration into a numerically manageable task. We test our method on an artificial mock galaxy survey, emulating characteristic features of the Sloan Digital Sky Survey data release 7, such as its survey geometry and luminosity-dependent biases. These tests demonstrate the numerical feasibility of our large scale Bayesian inference frame work when the parameter space has millions of dimensions. This method reveals and correctly treats the anti-correlation between bias amplitudes and power spectrum, which are not taken into account in current approaches to power spectrum estimation, a 20% effect across large ranges in k space. In addition, this method results in constrained realizations of density fields obtained without assuming the power spectrum or bias parameters

  14. Methods for Bayesian power spectrum inference with galaxy surveys

    SciTech Connect

    Jasche, Jens; Wandelt, Benjamin D.

    2013-12-10

    We derive and implement a full Bayesian large scale structure inference method aiming at precision recovery of the cosmological power spectrum from galaxy redshift surveys. Our approach improves upon previous Bayesian methods by performing a joint inference of the three-dimensional density field, the cosmological power spectrum, luminosity dependent galaxy biases, and corresponding normalizations. We account for all joint and correlated uncertainties between all inferred quantities. Classes of galaxies with different biases are treated as separate subsamples. This method therefore also allows the combined analysis of more than one galaxy survey. In particular, it solves the problem of inferring the power spectrum from galaxy surveys with non-trivial survey geometries by exploring the joint posterior distribution with efficient implementations of multiple block Markov chain and Hybrid Monte Carlo methods. Our Markov sampler achieves high statistical efficiency in low signal-to-noise regimes by using a deterministic reversible jump algorithm. This approach reduces the correlation length of the sampler by several orders of magnitude, turning the otherwise numerically unfeasible problem of joint parameter exploration into a numerically manageable task. We test our method on an artificial mock galaxy survey, emulating characteristic features of the Sloan Digital Sky Survey data release 7, such as its survey geometry and luminosity-dependent biases. These tests demonstrate the numerical feasibility of our large scale Bayesian inference frame work when the parameter space has millions of dimensions. This method reveals and correctly treats the anti-correlation between bias amplitudes and power spectrum, which are not taken into account in current approaches to power spectrum estimation, a 20% effect across large ranges in k space. In addition, this method results in constrained realizations of density fields obtained without assuming the power spectrum or bias parameters

  15. An iterative boundary element method for a wing-in-ground effect

    NASA Astrophysics Data System (ADS)

    Kinaci, Omer Kemal

    2014-06-01

    In this paper, an iterative boundary element method (IBEM) was proposed to solve for a wing-in-ground (WIG) effect. IBEM is a fast and accurate method used in many different fields of engineering and in this work; it is applied to a fluid flow problem assessing a wing in ground proximity. The theory and the developed code are validated first with other methods and the obtained results with the proposed method are found to be encouraging. Then, time consumptions of the direct and iterative methods were contrasted to evaluate the efficiency of IBEM. It is found out that IBEM dominates direct BEM in terms of time consumption in all trials. The iterative method seems very useful for quick assessment of a wing in ground proximity condition. After all, a NACA6409 wing section in ground vicinity is solved with IBEM to evaluate the WIG effect.

  16. A Ground Truthing Method for AVIRIS Overflights Using Canopy Absorption Spectra

    NASA Technical Reports Server (NTRS)

    Gamon, John A.; Serrano, Lydia; Roberts, Dar A.; Ustin, Susan L.

    1996-01-01

    Remote sensing for ecological field studies requires ground truthing for accurate interpretation of remote imagery. However, traditional vegetation sampling methods are time consuming and hard to relate to the scale of an AVIRIS scene. The large errors associated with manual field sampling, the contrasting formats of remote and ground data, and problems with coregistration of field sites with AVIRIS pixels can lead to difficulties in interpreting AVIRIS data. As part of a larger study of fire risk in the Santa Monica Mountains of southern California, we explored a ground-based optical method of sampling vegetation using spectrometers mounted both above and below vegetation canopies. The goal was to use optical methods to provide a rapid, consistent, and objective means of "ground truthing" that could be related both to AVIRIS imagery and to conventional ground sampling (e.g., plot harvests and pigment assays).

  17. Grounded Theory as a "Family of Methods": A Genealogical Analysis to Guide Research

    ERIC Educational Resources Information Center

    Babchuk, Wayne A.

    2011-01-01

    This study traces the evolution of grounded theory from a nuclear to an extended family of methods and considers the implications that decision-making based on informed choices throughout all phases of the research process has for realizing the potential of grounded theory for advancing adult education theory and practice. [This paper was…

  18. Geological disaster survey based on Curvelet transform with borehole Ground Penetrating Radar in Tonglushan old mine site.

    PubMed

    Tang, Xinjian; Sun, Tao; Tang, Zhijie; Zhou, Zenghui; Wei, Baoming

    2011-06-01

    Tonglushan old mine site located in Huangshi City, China, is very famous in the world. However, some of the ruins had suffered from geological disasters such as local deformation, surface cracking, in recent years. Structural abnormalities of rock-mass in deep underground were surveyed with borehole ground penetrating radar (GPR) to find out whether there were any mined galleries or mined-out areas below the ruins. With both the multiresolution analysis and sub-band directional of Curvelet transform, the feature information of targets' GPR signals were studied on Curvelet transform domain. Heterogeneity of geotechnical media and clutter jamming of complicated background of GPR signals could be conquered well, and the singularity characteristic information of typical rock mass signals could be extracted. Random noise had be removed by thresholding combined with Curvelet and the statistical characteristics of wanted signals and the noise, then direct wave suppression and the spatial distribution feature extraction could obtain a better result by making use of Curvelet transform directional. GprMax numerical modeling and analyzing of the sample data have verified the feasibility and effectiveness of our method. It is important and applicable for the analyzing of the geological structure and the disaster development about the Tonglushan old mine site. PMID:25084600

  19. Checklist and Pollard Walk butterfly survey methods on public lands

    USGS Publications Warehouse

    Royer, R.A.; Austin, J.E.; Newton, W.E.

    1998-01-01

    Checklist and Pollard Walk butterfly survey methods were contemporaneously applied to seven public sites in North Dakota during the summer of 1995. Results were compared for effect of method and site on total number of butterflies and total number of species detected per hour. Checklist searching produced significantly more butterfly detections per hour than Pollard Walks at all sites. Number of species detected per hour did not differ significantly either among sites or between methods. Many species were detected by only one method, and at most sites generalist and invader species were more likely to be observed during checklist searches than during Pollard Walks. Results indicate that checklist surveys are a more efficient means for initial determination of a species list for a site, whereas for long-term monitoring the Pollard Walk is more practical and statistically manageable. Pollard Walk transects are thus recommended once a prairie butterfly fauna has been defined for a site by checklist surveys.

  20. Electromagnetic survey of the K1070A burial ground at the Oak Ridge K-25 Site, Oak Ridge, Tennessee

    SciTech Connect

    Nyquist, J.E.; Emery, M.S.

    1993-01-01

    The K1070A burial ground, located at the K-25 Site on the Oak Ridge Reservation, received chemical and radioactive wastes from the late 1940s until 1975. Analysis of water samples collected from nearby monitoring wells indicates that contamination is migrating offsite. In November 1991, Oak Ridge National Laboratory (ORNL) personnel collected high-resolution electrical terrain conductivity data at the K1070A burial ground. A Model EM31 terrain conductivity meter manufactured by Geonics Limited was used in conjunction with the ORNL-developed Ultrasonic Ranging and Data System (USRADS) to perform the survey. The purposeof the survey was to provide Environmental Restoration (ER) staff with a detailed map of the spatial variation of the apparent electrical conductivity of the shallow subsurface (upper 3 m) to assist them in siting future monitoring wells closer to the waste area without drilling into the buried waste.

  1. Capacitance and Inductance based Rotor Ground Fault Location Method for Synchronous Machines

    NASA Astrophysics Data System (ADS)

    Palanisamy, Ramanathan

    2016-06-01

    This paper presents a capacitance and inductance based rotor ground fault location method for synchronous machines, which can detect and locate the ground fault in the rotor. The main contribution of this technique is to find the location of the ground fault in the rotor winding and reduce the repair time. This detection method is based on the measurement of inductance and capacitance of the rotor winding. It is suitable for salient pole synchronous machines. This method has been validated through experimental tests at the site.

  2. MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model -- GMG Linear Equation Solver Package Documentation

    USGS Publications Warehouse

    Wilson, John D.; Naff, Richard L.

    2004-01-01

    A geometric multigrid solver (GMG), based in the preconditioned conjugate gradient algorithm, has been developed for solving systems of equations resulting from applying the cell-centered finite difference algorithm to flow in porous media. This solver has been adapted to the U.S. Geological Survey ground-water flow model MODFLOW-2000. The documentation herein is a description of the solver and the adaptation to MODFLOW-2000.

  3. 40 CFR 141.401 - Sanitary surveys for ground water systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... request, any existing information that will enable the State to conduct a sanitary survey. (b) For the purposes of this subpart, a “sanitary survey,” as conducted by the State, includes but is not limited to... sources and operations and the distribution of safe drinking water. (c) The sanitary survey must...

  4. 40 CFR 141.401 - Sanitary surveys for ground water systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... request, any existing information that will enable the State to conduct a sanitary survey. (b) For the purposes of this subpart, a “sanitary survey,” as conducted by the State, includes but is not limited to... sources and operations and the distribution of safe drinking water. (c) The sanitary survey must...

  5. System and method for transferring telemetry data between a ground station and a control center

    NASA Technical Reports Server (NTRS)

    Ray, Timothy J. (Inventor); Ly, Vuong T. (Inventor)

    2012-01-01

    Disclosed herein are systems, computer-implemented methods, and tangible computer-readable media for coordinating communications between a ground station, a control center, and a spacecraft. The method receives a call to a simple, unified application programmer interface implementing communications protocols related to outer space, when instruction relates to receiving a command at the control center for the ground station generate an abstract message by agreeing upon a format for each type of abstract message with the ground station and using a set of message definitions to configure the command in the agreed upon format, encode the abstract message to generate an encoded message, and transfer the encoded message to the ground station, and perform similar actions when the instruction relates to receiving a second command as a second encoded message at the ground station from the control center and when the determined instruction type relates to transmitting information to the control center.

  6. Monitoring gray wolf populations using multiple survey methods

    USGS Publications Warehouse

    Ausband, David E.; Rich, Lindsey N.; Glenn, Elizabeth M.; Mitchell, Michael S.; Zager, Pete; Miller, David A.W.; Waits, Lisette P.; Ackerman, Bruce B.; Mack, Curt M.

    2013-01-01

    The behavioral patterns and large territories of large carnivores make them challenging to monitor. Occupancy modeling provides a framework for monitoring population dynamics and distribution of territorial carnivores. We combined data from hunter surveys, howling and sign surveys conducted at predicted wolf rendezvous sites, and locations of radiocollared wolves to model occupancy and estimate the number of gray wolf (Canis lupus) packs and individuals in Idaho during 2009 and 2010. We explicitly accounted for potential misidentification of occupied cells (i.e., false positives) using an extension of the multi-state occupancy framework. We found agreement between model predictions and distribution and estimates of number of wolf packs and individual wolves reported by Idaho Department of Fish and Game and Nez Perce Tribe from intensive radiotelemetry-based monitoring. Estimates of individual wolves from occupancy models that excluded data from radiocollared wolves were within an average of 12.0% (SD = 6.0) of existing statewide minimum counts. Models using only hunter survey data generally estimated the lowest abundance, whereas models using all data generally provided the highest estimates of abundance, although only marginally higher. Precision across approaches ranged from 14% to 28% of mean estimates and models that used all data streams generally provided the most precise estimates. We demonstrated that an occupancy model based on different survey methods can yield estimates of the number and distribution of wolf packs and individual wolf abundance with reasonable measures of precision. Assumptions of the approach including that average territory size is known, average pack size is known, and territories do not overlap, must be evaluated periodically using independent field data to ensure occupancy estimates remain reliable. Use of multiple survey methods helps to ensure that occupancy estimates are robust to weaknesses or changes in any 1 survey method

  7. Ground effects on V/STOL and STOL aircraft: A survey

    NASA Technical Reports Server (NTRS)

    Kuhn, R. E.; Eshleman, J.

    1985-01-01

    The flow fields encountered by jet- and fan-powered Vertical/Short Takeoff and Landing (V/STOL) aircraft operating in ground effect are reviewed and their general effects on the aerodynamic characteristics are discussed. The ground effects considered include: (1) the suckdown experienced by a single jet configuration in hover; (2) the fountain flow and additional suckdown experienced by multiple jet configurations in hover; (3) the ground vortex generated by jet and jet flap configurations in short takeoff and landing (STOL) operation and the associated aerodynamic and hot-gas-ingestion effects; and (4) the change in the downwash at the tail due to ground proximity. After over 30 years of research on V/STOL aircraft, the general flow phenomena are well-known and, in most areas, the effects of ground proximity can be established or can be determined experimentally. However, there are some anomalies in the current data base which are discussed.

  8. Ground effects on V/STOL and STOL aircraft - A survey

    NASA Technical Reports Server (NTRS)

    Eshlemen, J.; Kuhn, R. E.

    1985-01-01

    The flow fields encountered by jet- and fan-powered Vertical/Short Takeoff and Landing (V/STOL) aircraft operating in ground effect are reviewed and their general effects on the aerodynamic characteristics are discussed. The ground effects considered include (1) the suckdown experienced by a single jet configuration in hover, (2) the fountain flow and additional suckdown experienced by multiple jet configurations in hover, (3) the ground vortex generated by jet and jet flap configurations in Short Takeoff and Landing (STOL) operation and the associated aerodynamic and hot-gas-ingestion effects, and (4) the change in the downwash at the tail due to ground proximity. After over 30 years of research on V/STOL aircraft, the general flow phenomena are well known and, in most areas, the effects of ground proximity can be estimated or can be determined experimentally. However, there are some anomalies in the current data base which are discussed.

  9. Ice thickness profile surveying with ground penetrating radar at Artesonraju Glacier, Peru

    NASA Astrophysics Data System (ADS)

    Chisolm, Rachel; Rabatel, Antoine; McKinney, Daene; Condom, Thomas; Cochacin, Alejo; Davila Roller, Luzmilla

    2014-05-01

    Tropical glaciers are an essential component of the water resource systems in the mountainous regions where they are located, and a warming climate has resulted in the accelerated retreat of Andean glaciers in recent decades. The shrinkage of Andean glaciers influences the flood risk for communities living downstream as new glacial lakes have begun to form at the termini of some glaciers. As these lakes continue to grow in area and volume, they pose an increasing risk of glacial lake outburst floods (GLOFs). Ice thickness measurements have been a key missing link in studying the tropical glaciers in Peru and how climate change is likely to impact glacial melt and the growth of glacial lakes. Ground penetrating radar (GPR) has rarely been applied to glaciers in Peru to measure ice thickness, and these measurements can tell us a lot about how a warming climate will affect glaciers in terms of thickness changes. In the upper Paron Valley (Cordillera Blanca, Peru), an emerging lake has begun to form at the terminus of the Artesonraju Glacier, and this lake has key features, including overhanging ice and loose rock likely to create slides, that could trigger a catastrophic GLOF if the lake continues to grow. Because the glacier mass balance and lake mass balance are closely linked, ice thickness measurements and measurements of the bed slope of the Artesonraju Glacier and underlying bedrock can give us an idea of how the lake is likely to evolve in the coming decades. This study presents GPR data taken in July 2013 at the Artesonraju Glacier as part of a collaboration between the Unidad de Glaciologia y Recursos Hidricos (UGRH) of Peru, the Institut de Recherche pour le Développement (IRD) of France and the University of Texas at Austin (UT) of the United States of America. Two different GPR units belonging to UGRH and UT were used for subsurface imaging to create ice thickness profiles and to characterize the total volume of ice in the glacier. A common midpoint

  10. Autonomous and Remote-Controlled Airborne and Ground-Based Robotic Platforms for Adaptive Geophysical Surveying

    NASA Astrophysics Data System (ADS)

    Spritzer, J. M.; Phelps, G. A.

    2011-12-01

    Low-cost autonomous and remote-controlled robotic platforms have opened the door to precision-guided geophysical surveying. Over the past two years, the U.S. Geological Survey, Senseta, NASA Ames Research Center, and Carnegie Mellon University Silicon Valley, have developed and deployed small autonomous and remotely controlled vehicles for geophysical investigations. The purpose of this line of investigation is to 1) increase the analytical capability, resolution, and repeatability, and 2) decrease the time, and potentially the cost and map-power necessary to conduct near-surface geophysical surveys. Current technology has advanced to the point where vehicles can perform geophysical surveys autonomously, freeing the geoscientist to process and analyze the incoming data in near-real time. This has enabled geoscientists to monitor survey parameters; process, analyze and interpret the incoming data; and test geophysical models in the same field session. This new approach, termed adaptive surveying, provides the geoscientist with choices of how the remainder of the survey should be conducted. Autonomous vehicles follow pre-programmed survey paths, which can be utilized to easily repeat surveys on the same path over large areas without the operator fatigue and error that plague man-powered surveys. While initial deployments with autonomous systems required a larger field crew than a man-powered survey, over time operational experience costs and man power requirements will decrease. Using a low-cost, commercially available chassis as the base for autonomous surveying robotic systems promise to provide higher precision and efficiency than human-powered techniques. An experimental survey successfully demonstrated the adaptive techniques described. A magnetic sensor was mounted on a small rover, which autonomously drove a prescribed course designed to provide an overview of the study area. Magnetic data was relayed to the base station periodically, processed and gridded. A

  11. Comparative Study of Two Methods for Detection of Clostridium perfringens in Ground Beef.

    PubMed

    Emswiler, B S; Pierson, C J; Kotula, A W

    1977-03-01

    The tryptose-sulfite-cycloserine agar pour plate method was superior to selective enrichment in liquid sulfite medium for isolation of small numbers of Clostridium perfringens from frozen ground beef. PMID:16345236

  12. Comparative Study of Two Methods for Detection of Clostridium perfringens in Ground Beef

    PubMed Central

    Emswiler, B. S.; Pierson, C. J.; Kotula, A. W.

    1977-01-01

    The tryptose-sulfite-cycloserine agar pour plate method was superior to selective enrichment in liquid sulfite medium for isolation of small numbers of Clostridium perfringens from frozen ground beef. PMID:16345236

  13. Methods and Indicators for Assessment of Regional Ground-Water Conditions in the Southwestern United States

    USGS Publications Warehouse

    Tillman, Fred D; Leake, Stanley A.; Flynn, Marilyn E.; Cordova, Jeffrey T.; Schonauer, Kurt T.; Dickinson, Jesse E.

    2008-01-01

    Monitoring the status and trends in the availability of the Nation's ground-water supplies is important to scientists, planners, water managers, and the general public. This is especially true in the semiarid to arid southwestern United States where rapid population growth and limited surface-water resources have led to increased use of ground-water supplies and water-level declines of several hundred feet in many aquifers. Individual well observations may only represent aquifer conditions in a limited area, and wells may be screened over single or multiple aquifers, further complicating single-well interpretations. Additionally, changes in ground-water conditions may involve time scales ranging from days to many decades, depending on the timing of recharge, soil and aquifer properties, and depth to the water table. The lack of an easily identifiable ground-water property indicative of current conditions, combined with differing time scales of water-level changes, makes the presentation of ground-water conditions a difficult task, particularly on a regional basis. One approach is to spatially present several indicators of ground-water conditions that address different time scales and attributes of the aquifer systems. This report describes several methods and indicators for presenting differing aspects of ground-water conditions using water-level observations in existing data-sets. The indicators of ground-water conditions developed in this study include areas experiencing water-level decline and water-level rise, recent trends in ground-water levels, and current depth to ground water. The computer programs written to create these indicators of ground-water conditions and display them in an interactive geographic information systems (GIS) format are explained and results illustrated through analyses of ground-water conditions for selected alluvial basins in the Lower Colorado River Basin in Arizona.

  14. Scenistic Methods in Training: Definitions and Theory Grounding

    ERIC Educational Resources Information Center

    Lyons, Paul

    2010-01-01

    Purpose: The aim of this article is to describe the scenistic approach to training with corresponding activities and the theory bases that support the approach. Design/methodology/approach: Presented is the definition of the concept of scenistic training along with the step-by-step details of the implementation of the approach. Scenistic methods,…

  15. Aerial Survey Results for 131I Deposition on the Ground after the Fukushima Daiichi Nuclear Power Plant Accident

    SciTech Connect

    Torii, Tatsuo; Sugita, Takeshi; Okada, Colin E.; Reed, Michael S.; Blumenthal, Daniel J.

    2013-08-01

    In March 2011 the second largest accidental release of radioactivity in history occurred at the Fukushima Daiichi nuclear power plant following a magnitude 9.0 earthquake and subsequent tsunami. Teams from the U.S. Department of Energy, National Nuclear Security Administration Office of Emergency Response performed aerial surveys to provide initial maps of the dispersal of radioactive material in Japan. The initial results from the surveys did not report the concentration of 131I. This work reports on analyses performed on the initial survey data by a joint Japan-US collaboration to determine 131I ground concentration. This information is potentially useful in reconstruction of the inhalation and external exposure doses from this short-lived radionuclide. The deposited concentration of 134Cs is also reported.

  16. The use of high resolution ground and airborne magnetic surveys to evaluate the geometry of hydrothermal alteration zones over volcanic provinces (Invited)

    NASA Astrophysics Data System (ADS)

    Bouligand, C.; Glen, J. M.

    2013-12-01

    Geophysical methods can provide critical constraints on the distribution and volume of hydrothermal alteration, important parameters in understanding the evolution of geothermal systems. Because hydrothermal alteration modifies the magnetic properties of the volcanic substratum, magnetic surveys can be used to provide constraints on the distribution of hydrothermal alteration at depth. Using Yellowstone caldera as an example, we show that both ground and airborne magnetic surveys can be used to map and assess the volume of hydrothermal alteration. Ground magnetic surveys over unaltered volcanic terranes display high-amplitude, short-wavelength anomalies, in contrast to smooth, subdued magnetic anomalies over volcanic substrata demagnetized by hydrothermal alteration. We use this contrast to map areas of hydrothermal alteration in detail. Inverse methods applied to high-resolution airborne and ground magnetic data can be used to create three-dimensional models of the distribution of magnetization and thus illuminate the geometry of hydrothermal alteration. Because of the non-uniqueness of potential fields, the construction of inverse models requires simplifying assumptions on the distribution of magnetization, knowledge of induced and remanent magnetization of fresh and altered geological units, and detailed geological and geophysical data. Within the three hydrothermal sites that we investigated in Yellowstone National Park, subdued short-wavelength signal indicates pervasive demagnetization (alteration) of the shallow substratum that extends over larger areas than initially mapped by geology. These data also reveal that the largest degree of demagnetization (alteration) and maximum thicknesses of demagnetized (altered) substratum, reaching a few hundred meters, are associated with hydrothermal vents and with superficial hydrothermal alteration. Our three dimensional models of magnetization provide estimates of the volume of buried hydrothermal alteration ranging

  17. Interaction between two adjacent grounded sources in frequency domain semi-airborne electromagnetic survey

    NASA Astrophysics Data System (ADS)

    Zhou, Haigen; Lin, Jun; Liu, Changsheng; Kang, Lili; Li, Gang; Zeng, Xinsen

    2016-03-01

    Multi-source and multi-frequency emission method can make full use of the valuable and short flight time in frequency domain semi-airborne electromagnetic (FSAEM) exploration, which has potential to investigate the deep earth structure in complex terrain region. Because several sources are adjacent in multi-source emission method, the interaction of different sources should be considered carefully. An equivalent circuit model of dual-source is established in this paper to assess the interaction between two individual sources, where the parameters are given with the typical values based on the practical instrument system and its application. By simulating the output current of two sources in different cases, the influence from the adjacent source is observed clearly. The current waveforms show that the mutual resistance causes the fluctuation and drift in another source and that the mutual inductance causes transient peaks. A field test with dual-source was conducted to certify the existence of interaction between adjacent sources. The simulation of output current also shows that current errors at low frequency are mainly caused by the mutual resistance while those at high frequency are mainly due to the mutual inductance. Increasing the distance between neighboring sources is a proposed measure to reduce the emission signal errors with designed ones. The feasible distance is discussed in the end. This study gives a useful guidance to lay multi sources to meet the requirement of measurement accuracy in FSAEM survey.

  18. Interaction between two adjacent grounded sources in frequency domain semi-airborne electromagnetic survey.

    PubMed

    Zhou, Haigen; Lin, Jun; Liu, Changsheng; Kang, Lili; Li, Gang; Zeng, Xinsen

    2016-03-01

    Multi-source and multi-frequency emission method can make full use of the valuable and short flight time in frequency domain semi-airborne electromagnetic (FSAEM) exploration, which has potential to investigate the deep earth structure in complex terrain region. Because several sources are adjacent in multi-source emission method, the interaction of different sources should be considered carefully. An equivalent circuit model of dual-source is established in this paper to assess the interaction between two individual sources, where the parameters are given with the typical values based on the practical instrument system and its application. By simulating the output current of two sources in different cases, the influence from the adjacent source is observed clearly. The current waveforms show that the mutual resistance causes the fluctuation and drift in another source and that the mutual inductance causes transient peaks. A field test with dual-source was conducted to certify the existence of interaction between adjacent sources. The simulation of output current also shows that current errors at low frequency are mainly caused by the mutual resistance while those at high frequency are mainly due to the mutual inductance. Increasing the distance between neighboring sources is a proposed measure to reduce the emission signal errors with designed ones. The feasible distance is discussed in the end. This study gives a useful guidance to lay multi sources to meet the requirement of measurement accuracy in FSAEM survey. PMID:27036795

  19. Method of Controlling Steering of a Ground Vehicle

    NASA Technical Reports Server (NTRS)

    Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor)

    2016-01-01

    A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.

  20. An aerial survey method to estimate sea otter abundance

    USGS Publications Warehouse

    Bodkin, J.L.; Udevitz, M.S.

    1999-01-01

    Sea otters (Enhydra lutris) occur in shallow coastal habitats and can be highly visible on the sea surface. They generally rest in groups and their detection depends on factors that include sea conditions, viewing platform, observer technique and skill, distance, habitat and group size. While visible on the surface, they are difficult to see while diving and may dive in response to an approaching survey platform. We developed and tested an aerial survey method that uses intensive searches within portions of strip transects to adjust for availability and sightability biases. Correction factors are estimated independently for each survey and observer. In tests of our method using shore-based observers, we estimated detection probabilities of 0.52-0.72 in standard strip-transects and 0.96 in intensive searches. We used the survey method in Prince William Sound, Alaska to estimate a sea otter population size of 9,092 (SE = 1422). The new method represents an improvement over various aspects of previous methods, but additional development and testing will be required prior to its broad application.

  1. Collaborative study of a mineral oil method for the extraction of light filth from ground paprika.

    PubMed

    Thrasher, J J; Gentry, R

    1977-01-01

    An official first action method for the extraction of light filth from spices, 44.A03--44.A05, was modified for the analyses of ground paprika. The sample is extracted with isopropanol and light filth is isolated from 40% isopropanol with mineral oil. Eight collaborators analyzed 4 paprika samples, 2 by the official method and 2 by the proposed method. Average recoveries of added elytral squares were 97 and 66%, respectively, for the proposed and official methods. Recoveries of added rodent hairs were 94 and 61%, respectively. The method has been adopted as official first action for the extraction of light filth from ground paprika. PMID:833083

  2. GPR survey, as one of the best geophysical methods for social and industrial needs

    NASA Astrophysics Data System (ADS)

    Chernov, Anatolii

    2016-04-01

    This paper is about ways and methods of applying non-invasive geophysical method - Ground penetrating radar (GPR) survey in different spheres of science, industry, social life and culture. Author would like to show that geological methods could be widely used for solving great variety of industrial, human safety and other problems. In that article, we take GPR survey as an example of such useful geophysical methods. It is a fact that investigation of near surface underground medium is important process, which influence on development of different spheres of science and social life: investigation of near surface geology (layering, spreading of rock types, identification of voids, etc.), hydrogeology (depth to water horizons, their thickness), preparation step for construction of roads and buildings (civil geology, engineering geology), investigation of cultural heritage (burial places, building remains,...), ecological investigations (land slides, variation in underground water level, etc.), glaciology. These tasks can be solved by geological methods, but as usual, geophysical survey takes a lot of time and energy (especially electric current and resistivity methods, seismic survey). Author claims that GPR survey can be performed faster than other geophysical surveys and results of GPR survey are informative enough to make proper conclusions. Some problems even cannot be solved without GPR. For example, identification of burial place (one of author's research objects): results of magnetic and electric resistivity tomography survey do not contain enough information to identify burial place, but according to anomalies on GPR survey radarograms, presence of burial place can be proven. Identification of voids and non-magnetic objects also hardly can be done by another non-invasive geophysics surveys and GPR is applicable for that purpose. GPR can be applied for monitoring of dangerous processes in geological medium under roads, buildings, parks and other places of human

  3. A survey of unmanned ground vehicles with applications to agricultural and environmental sensing

    NASA Astrophysics Data System (ADS)

    Bonadies, Stephanie; Lefcourt, Alan; Gadsden, S. Andrew

    2016-05-01

    Unmanned ground vehicles have been utilized in the last few decades in an effort to increase the efficiency of agriculture, in particular, by reducing labor needs. Unmanned vehicles have been used for a variety of purposes including: soil sampling, irrigation management, precision spraying, mechanical weeding, and crop harvesting. In this paper, unmanned ground vehicles, implemented by researchers or commercial operations, are characterized through a comparison to other vehicles used in agriculture, namely airplanes and UAVs. An overview of different trade-offs of configurations, control schemes, and data collection technologies is provided. Emphasis is given to the use of unmanned ground vehicles in food crops, and includes a discussion of environmental impacts and economics. Factors considered regarding the future trends and potential issues of unmanned ground vehicles include development, management and performance. Also included is a strategy to demonstrate to farmers the safety and profitability of implementing the technology.

  4. GWM-a ground-water management process for the U.S. Geological Survey modular ground-water model (MODFLOW-2000)

    USGS Publications Warehouse

    Ahlfeld, David P.; Barlow, Paul M.; Mulligan, Anne E.

    2005-01-01

    GWM is a Ground?Water Management Process for the U.S. Geological Survey modular three?dimensional ground?water model, MODFLOW?2000. GWM uses a response?matrix approach to solve several types of linear, nonlinear, and mixed?binary linear ground?water management formulations. Each management formulation consists of a set of decision variables, an objective function, and a set of constraints. Three types of decision variables are supported by GWM: flow?rate decision variables, which are withdrawal or injection rates at well sites; external decision variables, which are sources or sinks of water that are external to the flow model and do not directly affect the state variables of the simulated ground?water system (heads, streamflows, and so forth); and binary variables, which have values of 0 or 1 and are used to define the status of flow?rate or external decision variables. Flow?rate decision variables can represent wells that extend over one or more model cells and be active during one or more model stress periods; external variables also can be active during one or more stress periods. A single objective function is supported by GWM, which can be specified to either minimize or maximize the weighted sum of the three types of decision variables. Four types of constraints can be specified in a GWM formulation: upper and lower bounds on the flow?rate and external decision variables; linear summations of the three types of decision variables; hydraulic?head based constraints, including drawdowns, head differences, and head gradients; and streamflow and streamflow?depletion constraints. The Response Matrix Solution (RMS) Package of GWM uses the Ground?Water Flow Process of MODFLOW to calculate the change in head at each constraint location that results from a perturbation of a flow?rate variable; these changes are used to calculate the response coefficients. For linear management formulations, the resulting matrix of response coefficients is then combined with other

  5. BLS Handbook of Methods for Surveys and Studies.

    ERIC Educational Resources Information Center

    Manpower Administration (DOL), Washington, DC.

    This handbook outlines the scope of the Bureau of Labor Statistics programs and the methods it uses to collect, tabulate, evaluate, and publish a wide range of economic and statistical information from the studies and surveys that it conducts. These statistical programs are organized according to subject matter areas. The broad subject areas…

  6. Using the Case Survey Method To Analyze Policy Studies

    ERIC Educational Resources Information Center

    Yin, Robert K.; Heald, Karen A.

    1975-01-01

    Describes a case study survey method that allows an analyst to aggregate (by means of a closed-ended questionnaire) the case study experiences and to assess the quality of each case study in a reliable and replicable manner. (Author/IRT)

  7. AgRISTARS: Agriculture and Resources Inventory Surveys Through Aerospace Remote Sensing. Enumerator's manual, 1981 ground data survey

    NASA Technical Reports Server (NTRS)

    1981-01-01

    General information and administrative instructions are provided for individuals gathering ground truth data to support research and development techniques for estimating crop acreage and production by remote sensing by satellite. Procedures are given for personal safety with regards to organophosphorus insecticides, for conducting interviews for periodic observations, for coding the crops identified and their growth stages, and for selecting sites for placing rain gages. Forms are included for those citizens agreeing to monitor the gages and record the rainfall. Segment selection is also considered.

  8. The Gaia spectrophotometric standard stars survey: II. Instrumental effects of six ground-based observing campaigns

    NASA Astrophysics Data System (ADS)

    Altavilla, G.; Marinoni, S.; Pancino, E.; Galleti, S.; Ragaini, S.; Bellazzini, M.; Cocozza, G.; Bragaglia, A.; Carrasco, J. M.; Castro, A.; Di Fabrizio, L.; Federici, L.; Figueras, F.; Gebran, M.; Jordi, C.; Masana, E.; Schuster, W.; Valentini, G.; Voss, H.

    2015-08-01

    The Gaia SpectroPhotometric Standard Stars (SPSS) survey started in 2006, was awarded almost 450 observing nights and accumulated almost 100 000 raw data frames with both photometric and spectroscopic observations. Such large observational effort requires careful, homogeneous, and automatic data reduction and quality control procedures. In this paper, we quantitatively evaluate instrumental effects that might have a significant (i.e., ≥ 1 %) impact on the Gaia SPSS flux calibration. The measurements involve six different instruments, monitored over the eight years of observations dedicated to the Gaia flux standards campaigns: DOLORES@TNG in La Palma, EFOSC2@NTT and ROSS@REM in La Silla, CAFOS@2.2 m in Calar Alto, BFOSC@Cassini in Loiano, and LaRuca@1.5 m in San Pedro Mártir. We examine and quantitatively evaluate the following effects: CCD linearity and shutter times, calibration frames stability, lamp flexures, second order contamination, light polarization, and fringing. We present methods to correct for the relevant effects which can be applied to a wide range of observational projects at similar instruments. Based on data obtained with BFOSC@Cassini in Loiano, Italy; EFOSC2@NTT in La Silla, Chile; DOLORES@TNG in La Palma, Spain; CAFOS@2.2 m in Calar Alto, Spain; LaRuca@1.5 m in San Pedro Mártir, Mexico (see acknowledgements for more details).

  9. Retina Lesion and Microaneurysm Segmentation using Morphological Reconstruction Methods with Ground-Truth Data

    SciTech Connect

    Karnowski, Thomas Paul; Govindaswamy, Priya; Tobin Jr, Kenneth William; Chaum, Edward; Abramoff, M.D.

    2008-01-01

    In this work we report on a method for lesion segmentation based on the morphological reconstruction methods of Sbeh et. al. We adapt the method to include segmentation of dark lesions with a given vasculature segmentation. The segmentation is performed at a variety of scales determined using ground-truth data. Since the method tends to over-segment imagery, ground-truth data was used to create post-processing filters to separate nuisance blobs from true lesions. A sensitivity and specificity of 90% of classification of blobs into nuisance and actual lesion was achieved on two data sets of 86 images and 1296 images.

  10. High-Resolution Ground-Based Magnetic Survey of a Buried Volcano: Anomaly B, Amargosa Desert, NV

    NASA Astrophysics Data System (ADS)

    McIlrath, J.; George, O.; Farrell, A. K.; Gallant, E.; Tavarez, S.; Downs, C. M.; Njoroge, M. W.; Wilson, J. A.; Connor, C.; Connor, L.; Kruse, S.

    2015-12-01

    Aeromagnetic surveys over the Amargosa Desert, Nevada, have revealed the presence of several magnetic anomalies that have been interpreted to be caused by buried volcanoes; many of these anomalies have been confirmed by drilling. We present data collected from a high-resolution, ground-based magnetic survey over Anomaly B, the largest of these anomalies, that reveal details about a buried crater and its associated lava flow, not previously observed in the aeromagnetic surveys. These details provide insight into the nature of the eruption and the volume of this buried volcano. Results from non-linear inversion demarcate a crater with a diameter of approximately 700 m and a base approximately 150 m below the ground surface. Coupled with well log data, the inversion results suggest a total volume for the Anomaly B crater area and associated lava flows of approximately 1.0 ± 0.4 km3, based on an estimated lava flow field area of 24 km2 and a lava thickness of 42 ± 15 m.

  11. Survey of methods for calculating sensitivity of general eigenproblems

    NASA Technical Reports Server (NTRS)

    Murthy, Durbha V.; Haftka, Raphael T.

    1987-01-01

    A survey of methods for sensitivity analysis of the algebraic eigenvalue problem for non-Hermitian matrices is presented. In addition, a modification of one method based on a better normalizing condition is proposed. Methods are classified as Direct or Adjoint and are evaluated for efficiency. Operation counts are presented in terms of matrix size, number of design variables and number of eigenvalues and eigenvectors of interest. The effect of the sparsity of the matrix and its derivatives is also considered, and typical solution times are given. General guidelines are established for the selection of the most efficient method.

  12. The Second National Sun Survey: overview and methods.

    PubMed

    Marrett, Loraine D; Northrup, David A; Pichora, Erin C; Spinks, Michael T; Rosen, Cheryl F

    2010-01-01

    The Second National Sun Survey (NSS2) was carried out in 2006 to estimate ultraviolet radiation (UVR) exposure, sun protection and related knowledge, attitudes and beliefs among Canadians. This paper provides a detailed overview of NSS2 methods and discusses the strengths and limitations of the survey. The NSS2 consists of two questionnaires administered to two samples of adults (age 16+ years). The base sample provides in-depth information on UVR exposure, protective behaviours, tanning, and knowledge, attitudes and beliefs about sun safety for adults, as well as some sun behaviour information for a sample of their children aged 1-12 years. The shorter comparison sample facilitates direct comparison with the 1996 first national sun survey. Data were collected using computer-assisted telephone interviewing, and sample weights were computed for all respondents for estimation and analysis of both adult and child data. Base sample interviews were completed for 7,121 adults, of whom 1,437 reported on the sun behaviour of one of their children, and the comparison sample yielded 2,115 interviews. Response rates were 63% for both surveys. The NSS2 provides in-depth and up-to-date UVR exposure information among Canadians. The results of this survey will aid health promotion experts and policy-makers in developing effective programs to minimize UVR exposure. A public use data file and training in statistical analysis of the NSS2 has been made available to data analysts from across Canada. Key strengths and limitations identified in this survey will inform the development and implementation of future sun surveys. PMID:21033539

  13. Prenotification, Incentives, and Survey Modality: An Experimental Test of Methods to Increase Survey Response Rates of School Principals

    ERIC Educational Resources Information Center

    Jacob, Robin Tepper; Jacob, Brian

    2012-01-01

    Teacher and principal surveys are among the most common data collection techniques employed in education research. Yet there is remarkably little research on survey methods in education, or about the most cost-effective way to raise response rates among teachers and principals. In an effort to explore various methods for increasing survey response…

  14. Collaborative study of a method for the extraction of light filth from ground turmeric.

    PubMed

    Glaze, L E

    1975-05-01

    An improved method has been developed for the extraction of light filth from ground turmeric. The method involves an isopropanol defatting followed by a direct flotation from 40% isopropanol with Tween 80-EDTA (1+1) and hot mineral oil. Collaborative results show that the method is rapid and yields better filth recoveries than the official first action method, 44.118. The method has been adopted as official first action to replace 44.118. PMID:1170163

  15. Survey of aircraft subcritical flight flutter testing methods

    NASA Technical Reports Server (NTRS)

    Rosenbaum, R.

    1974-01-01

    The results of a survey of U. S., British and French subcritical aircraft flight flutter testing methods are presented and evaluation of the applicability of these methods to the testing of the space shuttle are discussed. Ten U. S. aircraft programs covering the large civil transport aircraft and a variety of military aircraft are reviewed. In addition, three major French and British programs are covered by the survey. The significant differences between the U. S., French and British practices in the areas of methods of excitation, data acquisition, transmission and analysis are reviewed. The effect of integrating the digital computer into the flight flutter test program is discussed. Significant saving in analysis and flight test time are shown to result from the use of special digital computer routines and digital filters.

  16. Integration of real time kinematic satellite navigation with ground-penetrating radar surveys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture, environmental mapping, and construction benefit from subsurface imaging by revealing the spatial variability of underground features. Features surveyed of agricultural interest are bedrock depth, soil horizon thicknesses, and buried–object features such as drainage pipe. For t...

  17. A survey of ground operations tools developed to simulate the pointing of space telescopes and the design for WISE

    NASA Technical Reports Server (NTRS)

    Fabinsky, Beth

    2006-01-01

    WISE, the Wide Field Infrared Survey Explorer, is scheduled for launch in June 2010. The mission operations system for WISE requires a software modeling tool to help plan, integrate and simulate all spacecraft pointing and verify that no attitude constraints are violated. In the course of developing the requirements for this tool, an investigation was conducted into the design of similar tools for other space-based telescopes. This paper summarizes the ground software and processes used to plan and validate pointing for a selection of space telescopes; with this information as background, the design for WISE is presented.

  18. Processing the ground vibration signal produced by debris flows: the methods of amplitude and impulses compared

    NASA Astrophysics Data System (ADS)

    Arattano, M.; Abancó, C.; Coviello, V.; Hürlimann, M.

    2014-12-01

    Ground vibration sensors have been increasingly used and tested, during the last few years, as devices to monitor debris flows and they have also been proposed as one of the more reliable devices for the design of debris flow warning systems. The need to process the output of ground vibration sensors, to diminish the amount of data to be recorded, is usually due to the reduced storing capabilities and the limited power supply, normally provided by solar panels, available in the high mountain environment. There are different methods that can be found in literature to process the ground vibration signal produced by debris flows. In this paper we will discuss the two most commonly employed: the method of impulses and the method of amplitude. These two methods of data processing are analyzed describing their origin and their use, presenting examples of applications and their main advantages and shortcomings. The two methods are then applied to process the ground vibration raw data produced by a debris flow occurred in the Rebaixader Torrent (Spanish Pyrenees) in 2012. The results of this work will provide means for decision to researchers and technicians who find themselves facing the task of designing a debris flow monitoring installation or a debris flow warning equipment based on the use of ground vibration detectors.

  19. Radiological decontamination, survey, and statistical release method for vehicles

    SciTech Connect

    Goodwill, M.E.; Lively, J.W.; Morris, R.L.

    1996-06-01

    Earth-moving vehicles (e.g., dump trucks, belly dumps) commonly haul radiologically contaminated materials from a site being remediated to a disposal site. Traditionally, each vehicle must be surveyed before being released. The logistical difficulties of implementing the traditional approach on a large scale demand that an alternative be devised. A statistical method for assessing product quality from a continuous process was adapted to the vehicle decontamination process. This method produced a sampling scheme that automatically compensates and accommodates fluctuating batch sizes and changing conditions without the need to modify or rectify the sampling scheme in the field. Vehicles are randomly selected (sampled) upon completion of the decontamination process to be surveyed for residual radioactive surface contamination. The frequency of sampling is based on the expected number of vehicles passing through the decontamination process in a given period and the confidence level desired. This process has been successfully used for 1 year at the former uranium millsite in Monticello, Utah (a cleanup site regulated under the Comprehensive Environmental Response, Compensation, and Liability Act). The method forces improvement in the quality of the decontamination process and results in a lower likelihood that vehicles exceeding the surface contamination standards are offered for survey. Implementation of this statistical sampling method on Monticello projects has resulted in more efficient processing of vehicles through decontamination and radiological release, saved hundreds of hours of processing time, provided a high level of confidence that release limits are met, and improved the radiological cleanliness of vehicles leaving the controlled site.

  20. Phenomenography and Grounded Theory as Research Methods in Computing Education Research Field

    ERIC Educational Resources Information Center

    Kinnunen, Paivi; Simon, Beth

    2012-01-01

    This paper discusses two qualitative research methods, phenomenography and grounded theory. We introduce both methods' data collection and analysis processes and the type or results you may get at the end by using examples from computing education research. We highlight some of the similarities and differences between the aim, data collection and…

  1. 30 CFR 75.701-2 - Approved method of grounding metallic frames, casings and other enclosures receiving power from...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved method of grounding metallic frames... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.701-2 Approved method of grounding metallic frames, casings and other enclosures receiving power from single-phase...

  2. 30 CFR 75.701-2 - Approved method of grounding metallic frames, casings and other enclosures receiving power from...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved method of grounding metallic frames... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.701-2 Approved method of grounding metallic frames, casings and other enclosures receiving power from single-phase...

  3. Rapid Mapping Method Based on Free Blocks of Surveys

    NASA Astrophysics Data System (ADS)

    Yu, Xianwen; Wang, Huiqing; Wang, Jinling

    2016-06-01

    While producing large-scale larger than 1:2000 maps in cities or towns, the obstruction from buildings leads to difficult and heavy tasks of measuring mapping control points. In order to avoid measuring the mapping control points and shorten the time of fieldwork, in this paper, a quick mapping method is proposed. This method adjusts many free blocks of surveys together, and transforms the points from all free blocks of surveys into the same coordinate system. The entire surveying area is divided into many free blocks, and connection points are set on the boundaries between free blocks. An independent coordinate system of every free block is established via completely free station technology, and the coordinates of the connection points, detail points and control points in every free block in the corresponding independent coordinate systems are obtained based on poly-directional open traverses. Error equations are established based on connection points, which are determined together to obtain the transformation parameters. All points are transformed from the independent coordinate systems to a transitional coordinate system via the transformation parameters. Several control points are then measured by GPS in a geodetic coordinate system. All the points can then be transformed from the transitional coordinate system to the geodetic coordinate system. In this paper, the implementation process and mathematical formulas of the new method are presented in detail, and the formula to estimate the precision of surveys is given. An example has demonstrated that the precision of using the new method could meet large-scale mapping needs.

  4. A projection gradient method for computing ground state of spin-2 Bose–Einstein condensates

    SciTech Connect

    Wang, Hanquan

    2014-10-01

    In this paper, a projection gradient method is presented for computing ground state of spin-2 Bose–Einstein condensates (BEC). We first propose the general projection gradient method for solving energy functional minimization problem under multiple constraints, in which the energy functional takes real functions as independent variables. We next extend the method to solve a similar problem, where the energy functional now takes complex functions as independent variables. We finally employ the method into finding the ground state of spin-2 BEC. The key of our method is: by constructing continuous gradient flows (CGFs), the ground state of spin-2 BEC can be computed as the steady state solution of such CGFs. We discretized the CGFs by a conservative finite difference method along with a proper way to deal with the nonlinear terms. We show that the numerical discretization is normalization and magnetization conservative and energy diminishing. Numerical results of the ground state and their energy of spin-2 BEC are reported to demonstrate the effectiveness of the numerical method.

  5. In situ push-pull method to determine ground water denitrification in riparian zones.

    PubMed

    Addy, Kelly; Kellogg, D Q; Gold, Arthur J; Groffman, Peter M; Ferendo, Gina; Sawyer, Carl

    2002-01-01

    To quantify ground water denitrification in discrete locations of riparian aquifers, we modified and evaluated an in situ method based on conservative tracers and 15N-enriched nitrate. Ground water was "pushed" (i.e., injected) into a mini-piezometer and then "pulled" (i.e., extracted) from the same mini-piezometer after an incubation period. This push-pull method was applied in replicate mini-piezometers at two Rhode Island riparian sites, one fresh water and one brackish water. Conservative tracer pretests were conducted to determine incubation periods, ranging from 5 to 120 h, to optimize recovery of introduced plumes. For nitrate push-pull tests, we used two conservative tracers, sulfur hexafluoride and bromide, to provide insight into plume recovery. The two conservative tracers behaved similarly. The dosing solutions were amended with 15N-enriched nitrate that enabled us to quantify the mass of denitrification gases generated during the incubation period. The in situ push-pull method detected substantial denitrification rates at a site where we had previously observed high denitrification rates. At our brackish site, we found high rates of ground water denitrification in marsh locations and minimal denitrification in soils fringing the marsh. The push-pull method can provide useful insights into spatial and temporal patterns of denitrification in riparian zones. The method is robust and results are not seriously affected by dilution or degassing from ground water to soil air. In conjunction with measurements of ground water flow-paths, this method holds promise for evaluating the influence of site and management factors on the ground water nitrate removal capacity of riparian zones. PMID:12026069

  6. Aeroelastic analysis and ground vibration survey of the NASA, Grumman American Yankee modified for spin testing

    NASA Technical Reports Server (NTRS)

    Kroeger, R. A.

    1977-01-01

    A complete ground vibration and aeroelastic analysis was made of a modified version of the Grumman American Yankee. The aircraft had been modified for four empennage configurations, a wing boom was added, a spin chute installed and provisions included for large masses in the wing tip to vary the lateral and directional inertia. Other minor changes were made which have much less influence on the flutter and vibrations. Neither static divergence nor aileron reversal was considered since the wing structure was not sufficiently changed to affect its static aeroelastic qualities. The aircraft was found to be free from flutter in all of the normal modes explored in the ground shake test. The analysis demonstrated freedom from flutter up to 214 miles per hour.

  7. Seeking Construct Validity Grounded in Constructivist Epistemology: Development of the Survey of Contemporary Learning Environments

    ERIC Educational Resources Information Center

    Schuh, Kathy L.; Kuo, Yi-Lung

    2015-01-01

    This study focused on the development of a new classroom environment instrument for late-elementary students. The development of the survey of contemporary learning environments (SoCLE) followed a content analysis of three similar instruments on constructivist learning environments and the literature on characteristics of contemporary learning…

  8. Relationships between ground and airborne gamma-ray spectrometric survey data, North Ras Millan, Southern Sinai Peninsula, Egypt.

    PubMed

    Youssef, Mohamed A S

    2016-02-01

    In the last decades of years, there was considerable growth in the use of airborne gamma-ray spectrometry. With this growth, there was an increasing need to standardize airborne measurements, so that they can be independent of survey parameters. Acceptable procedures were developed for converting airborne to ground gamma-ray spectrometric measurements of total-count intensity as well as, potassium, equivalent uranium and equivalent thorium concentrations, due to natural sources of radiation. The present study aims mainly to establish relationships between ground and airborne gamma-ray spectrometric data, North Ras Millan, Southern Sinai Peninsula, Egypt. The relationships between airborne and ground gamma-ray spectrometric data were deduced for the original and separated rock units in the study area. Various rocks in the study area, represented by Quaternary Wadi sediments, Cambro-Ordovician sandstones, basic dykes and granites, are shown on the detailed geologic map. The structures are displayed, which located on the detailed geologic map, are compiled from the integration of previous geophysical and surface geological studies. PMID:26650828

  9. Apparatus for and method of testing an electrical ground fault circuit interrupt device

    DOEpatents

    Andrews, Lowell B.

    1998-01-01

    An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined.

  10. Apparatus for and method of testing an electrical ground fault circuit interrupt device

    DOEpatents

    Andrews, L.B.

    1998-08-18

    An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined. 17 figs.

  11. Wavelet transform-based fault diagnosis and line selection method of small current grounding system

    NASA Astrophysics Data System (ADS)

    Yang, Ni; Zhang, Shuqing; Zhang, Liguo; Zhang, Kexin; Sun, Lingyun

    2008-12-01

    Small current grounding system is the system that the neutral point doesn't ground or grounds across the arc suppressing coils, which has been applied commonly in distribution system of many countries. As the grounding fault occurs, current is the one caused by capacity of circuit to ground only and it is rather small. The status of fault is complexity, e.g., the electromagnet interferes together with the amplified impact of zero-order loops to high-order singularity waves and various temporary variables. All these result in the lower ratio of the fault element signal to noise caused by zero-order current. In this paper, the position of signal singularity and the magnitude of the singularity degree are analyzed based on the variable focus character of wavelet, and the time fault occurs is then determined. The series db wavelet with close sustain is adopted, and the line selection is according to the zero-order voltage of the generatrix and the current of various outlet line. It is proved by the experiment that the fault circuit diagnosis method based on wavelet analysis to the character of temporary status of single-phase grounding fault plays an important role to a finer line selection.

  12. Application of ground-penetrating radar methods in determining hydrogeologic conditions in a karst area, west-central Florida

    USGS Publications Warehouse

    Barr, G.L.

    1993-01-01

    Ground-penetrating radar (GPR) is useful as a surface geophysical method for exploring geology and subsurface features in karst settings. Interpretation of GPR data was used to infer lithology and hydrogeologic conditions in west-central Florida. This study demonstrates how GPR methods can be used to investigate the hydrogeology of an area. GPR transmits radio- frequency electromagnetic waves into the ground and receives reflected energy waves from subsurface interfaces. Subsurface profiles showing sediment thickness, depth to water table and clay beds, karst development, buried objects, and lake-bottom structure were produced from GPR traverses obtained during December 1987 and March 1990 in Pinellas, Hillsborough, and Hardee Counties in west-central Florida. Performance of the GPR method is site specific, and data collected are principally affected by the sediment and pore fluids, conductances and dielectric constants. Effective exploration depths of the GPR surveys through predominately unsaturated and saturated sand and clay sediments at five study sites ranged from a few feet to greater than 50 feet below land surface. Exploration depths were limited when high conductivity clay was encountered, whereas greater exploration depths were possible in material composed of sand. Application of GPR is useful in profiling subsurface conditions, but proper interpretation depends upon the user's knowledge of the equipment and the local hydrogeological setting, as well as the ability to interpret the graphic profile.

  13. Experimental method for forecasting propagation delay of ground wave for timing signal.

    NASA Astrophysics Data System (ADS)

    Liang, Zhonghuan

    1998-06-01

    Up to now, only two methods for forecasting the propagation delay of a ground wave for timing signals have been formally published. The author has further developed the method, described by Miao Yongrei et al. (1979). The results show that with the number M = 3 for the segments, the precision of the forecasted values of the time delay is much better than that from the method in which the whole path is regarded as a homogeneous one.

  14. Pan-European survey on the occurrence of selected polar organic persistent pollutants in ground water.

    PubMed

    Loos, Robert; Locoro, Giovanni; Comero, Sara; Contini, Serafino; Schwesig, David; Werres, Friedrich; Balsaa, Peter; Gans, Oliver; Weiss, Stefan; Blaha, Ludek; Bolchi, Monica; Gawlik, Bernd Manfred

    2010-07-01

    This study provides the first pan-European reconnaissance of the occurrence of polar organic persistent pollutants in European ground water. In total, 164 individual ground-water samples from 23 European Countries were collected and analysed (among others) for 59 selected organic compounds, comprising pharmaceuticals, antibiotics, pesticides (and their transformation products), perfluorinated acids (PFAs), benzotriazoles, hormones, alkylphenolics (endocrine disrupters), Caffeine, Diethyltoluamide (DEET), and Triclosan. The most relevant compounds in terms of frequency of detection and maximum concentrations detected were DEET (84%; 454 ng/L), Caffeine (83%; 189 ng/L), PFOA (66%; 39 ng/L), Atrazine (56%; 253 ng/L), Desethylatrazine (55%; 487 ng/L), 1H-Benzotriazole (53%; 1032 ng/L), Methylbenzotriazole (52%; 516 ng/L), Desethylterbutylazine (49%; 266 ng/L), PFOS (48%, 135 ng/L), Simazine (43%; 127 ng/L), Carbamazepine (42%; 390 ng/L), nonylphenoxy acetic acid (NPE(1)C) (42%; 11 microg/L), Bisphenol A (40%; 2.3 microg/L), PFHxS (35%; 19 ng/L), Terbutylazine (34%; 716 ng/L), Bentazone (32%; 11 microg/L), Propazine (32%; 25 ng/L), PFHpA (30%; 21 ng/L), 2,4-Dinitrophenol (29%; 122 ng/L), Diuron (29%; 279 ng/L), and Sulfamethoxazole (24%; 38 ng/L). The chemicals which were detected most frequently above the European ground water quality standard for pesticides of 0.1 microg/L were Chloridazon-desphenyl (26 samples), NPE(1)C (20), Bisphenol A (12), Benzotriazole (8), N,N'-Dimethylsulfamid (DMS) (8), Desethylatrazine (6), Nonylphenol (6), Chloridazon-methyldesphenyl (6), Methylbenzotriazole (5), Carbamazepine (4), and Bentazone (4). However, only 1.7% of all single analytical measurements (in total 8000) were above this threshold value of 0.1 microg/L; 7.3% were > than 10 ng/L. PMID:20554303

  15. A Forest Biomass Survey by Bitterlich Method With an Electronic Relascope for Satellite Data Validation

    NASA Astrophysics Data System (ADS)

    Suzuki, R.; Ishii, R.; Takao, G.; Nakano, T.; Yasuda, T.

    2006-12-01

    For the better understanding of the carbon cycle in the global ecosystem, an investigation on the spatio- temporal variation of the carbon stock which is stored as vegetation biomass should be important. "PALSAR (Phased Array type L-band Synthetic Aperture Radar)", an onboard sensor of the polar orbiting satellite "ALOS (Advanced Land Observing Satellite)" launched in January 2006, provides the information which can be used for the above-ground biomass estimation. It is expected that ALOS/PALSAR provides us a great opportunity to analyze the biomass dynamics over extensive regions. To derive the biomass from the ALOS/PALSAR measurement, it is inevitable to acquire in situ biomass measurement by ground-based forest surveys. Moreover, it is required to obtain such ground-based information at as possible many sites, because the region targeted by satellite remote sensing is extensive and the forest structure in that region is various. Therefore, a quick forest survey will be required to measure the biomass at as possible many sites. For the quick measurement of the forest above-ground biomass, we propose a way that is a combination of Bitterlich angle count sampling method and sampled-tree measuring method. First, a tree which has wider trunk than the basal area factor (BAF) angle is identified by the relascope from a representative point in the target forest. Next, the tree height and the breast height diameter (DBH) of the sampled tree are measured. The biomass of the tree is estimate by the allometric equation with the tree height and DBH measurements. Through these processes, the biomass density of the sampled tree per the forest area defined by the BAF is estimated. By sampling and measuring all trees (usually around 20 trees), the biomass of the forest can be estimate. A brand-new electronic relascope (Criterion RD 1000, Laser Technology Inc.) and laser range finder (TruPulse 200, Laser Technology Inc.) are used for the tree height and DBH measurements to

  16. Survey and Method for Determination of Trajectory Predictor Requirements

    NASA Technical Reports Server (NTRS)

    Rentas, Tamika L.; Green, Steven M.; Cate, Karen Tung

    2009-01-01

    A survey of air-traffic-management researchers, representing a broad range of automation applications, was conducted to document trajectory-predictor requirements for future decision-support systems. Results indicated that the researchers were unable to articulate a basic set of trajectory-prediction requirements for their automation concepts. Survey responses showed the need to establish a process to help developers determine the trajectory-predictor-performance requirements for their concepts. Two methods for determining trajectory-predictor requirements are introduced. A fast-time simulation method is discussed that captures the sensitivity of a concept to the performance of its trajectory-prediction capability. A characterization method is proposed to provide quicker, yet less precise results, based on analysis and simulation to characterize the trajectory-prediction errors associated with key modeling options for a specific concept. Concept developers can then identify the relative sizes of errors associated with key modeling options, and qualitatively determine which options lead to significant errors. The characterization method is demonstrated for a case study involving future airport surface traffic management automation. Of the top four sources of error, results indicated that the error associated with accelerations to and from turn speeds was unacceptable, the error associated with the turn path model was acceptable, and the error associated with taxi-speed estimation was of concern and needed a higher fidelity concept simulation to obtain a more precise result

  17. Investigating the Local and High Redshift Universe With Deep Survey Data and Ground-Based Spectroscopy

    NASA Astrophysics Data System (ADS)

    Masters, Daniel Charles

    Large multiwavelength surveys are now driving the frontiers of astronomical research. I describe results from my work using data from two large astronomical surveys: the Cosmic Evolution Survey (COSMOS), which has obtained deep photometric and spectroscopic data on two square degrees of the sky using many of the most powerful telescopes in the world, and the WFC3 Infrared Spectroscopic Parallels (WISP) Survey, which uses the highly sensitive slitless spectroscopic capability of the Hubble Space Telescope Wide Field Camera 3 to detect star-forming galaxies over most of the universe's history. First I describe my work on the evolution of the high-redshift quasar luminosity function, an important observational quantity constraining the growth of the supermassive black holes in the early universe. I show that the number density of faint quasars declines rapidly above z ˜ 3. This result is discussed in the context of cosmic reionization and the coevolution of galaxies and their central black holes. Next I present results of a multi-year campaign of near-infrared spectroscopy with FIRE, a world-class near-infrared spectrometer on the Magellan Baade 6.5 meter telescope in Chile, targeting emission-line galaxies at z ˜ 2 discovered with the Hubble Space Telescope. Our results showed that the typical emission-line galaxy at this redshift has low-metallicity, low dust obscuration, high ionization parameter, and little evidence for significant active galactic nucleus (AGN) contribution to the emission lines. We also find evidence that high redshift star-forming galaxies have enhanced nitrogen abundances. This result has interesting implications for the nature of the star formation in such galaxies -- in particular, it could mean that a large fraction of such galaxies harbor substantial populations of Wolf-Rayet stars, which are massive, evolved stars ejecting large amounts of enriched matter into the interstellar medium. Finally, I will discuss the discovery of three

  18. GROUND WATER MONITORING AND SAMPLING: MULTI-LEVEL VERSUS TRADITIONAL METHODS WHATS WHAT?

    EPA Science Inventory

    After years of research and many publications, the question still remains: What is the best method to collect representative ground water samples from monitoring wells? Numerous systems and devices are currently available for obtaining both multi-level samples as well as traditi...

  19. Using Popular Media and a Collaborative Approach to Teaching Grounded Theory Research Methods

    ERIC Educational Resources Information Center

    Creamer, Elizabeth G.; Ghoston, Michelle R.; Drape, Tiffany; Ruff, Chloe; Mukuni, Joseph

    2012-01-01

    Popular movies were used in a doctoral-level qualitative research methods course as a way to help students learn about how to collect and analyze qualitative observational data in order to develop a grounded theory. The course was designed in such a way that collaboration was central to the generation of knowledge. Using media depictions had the…

  20. 30 CFR 75.701-3 - Approved methods of grounding metallic frames, casings and other enclosures of electric equipment...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., casings and other enclosures of electric equipment receiving power from direct current power systems with... Grounding § 75.701-3 Approved methods of grounding metallic frames, casings and other enclosures of electric equipment receiving power from direct current power systems with one polarity grounded. For the purpose...

  1. 30 CFR 75.701-3 - Approved methods of grounding metallic frames, casings and other enclosures of electric equipment...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., casings and other enclosures of electric equipment receiving power from direct current power systems with... Grounding § 75.701-3 Approved methods of grounding metallic frames, casings and other enclosures of electric equipment receiving power from direct current power systems with one polarity grounded. For the purpose...

  2. 30 CFR 75.701-3 - Approved methods of grounding metallic frames, casings and other enclosures of electric equipment...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., casings and other enclosures of electric equipment receiving power from direct current power systems with... Grounding § 75.701-3 Approved methods of grounding metallic frames, casings and other enclosures of electric equipment receiving power from direct current power systems with one polarity grounded. For the purpose...

  3. 30 CFR 75.701-3 - Approved methods of grounding metallic frames, casings and other enclosures of electric equipment...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., casings and other enclosures of electric equipment receiving power from direct current power systems with... Grounding § 75.701-3 Approved methods of grounding metallic frames, casings and other enclosures of electric equipment receiving power from direct current power systems with one polarity grounded. For the purpose...

  4. 30 CFR 75.701-3 - Approved methods of grounding metallic frames, casings and other enclosures of electric equipment...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., casings and other enclosures of electric equipment receiving power from direct current power systems with... Grounding § 75.701-3 Approved methods of grounding metallic frames, casings and other enclosures of electric equipment receiving power from direct current power systems with one polarity grounded. For the purpose...

  5. Survey of predators and sampling method comparison in sweet corn.

    PubMed

    Musser, Fred R; Nyrop, Jan P; Shelton, Anthony M

    2004-02-01

    Natural predation is an important component of integrated pest management that is often overlooked because it is difficult to quantify and perceived to be unreliable. To begin incorporating natural predation into sweet corn, Zea mays L., pest management, a predator survey was conducted and then three sampling methods were compared for their ability to accurately monitor the most abundant predators. A predator survey on sweet corn foliage in New York between 1999 and 2001 identified 13 species. Orius insidiosus (Say), Coleomegilla maculata (De Geer), and Harmonia axyridis (Pallas) were the most numerous predators in all years. To determine the best method for sampling adult and immature stages of these predators, comparisons were made among nondestructive field counts, destructive counts, and yellow sticky cards. Field counts were correlated with destructive counts for all populations, but field counts of small insects were biased. Sticky cards underrepresented immature populations. Yellow sticky cards were more attractive to C. maculata adults than H. axyridis adults, especially before pollen shed, making coccinellid population estimates based on sticky cards unreliable. Field counts were the most precise method for monitoring adult and immature stages of the three major predators. Future research on predicting predation of pests in sweet corn should be based on field counts of predators because these counts are accurate, have no associated supply costs, and can be made quickly. PMID:14998137

  6. Survey of NASA V and V Processes/Methods

    NASA Technical Reports Server (NTRS)

    Pecheur, Charles; Nelson, Stacy

    2002-01-01

    The purpose of this report is to describe current NASA Verification and Validation (V&V) techniques and to explain how these techniques are applicable to 2nd Generation RLV Integrated Vehicle Health Management (IVHM) software. It also contains recommendations for special V&V requirements for IVHM. This report is divided into the following three sections: 1) Survey - Current NASA V&V Processes/Methods; 2) Applicability of NASA V&V to 2nd Generation RLV IVHM; and 3) Special 2nd Generation RLV IVHM V&V Requirements.

  7. U. S. Geological Survey begins seismic ground response experiments in Washington State

    USGS Publications Warehouse

    Tarr, A.C.; King, K.W.

    1987-01-01

    The men were Denver-based U.S Geological Survey (USGS) geophysicists working on the Urban Hazards Field Investigations project. On the previous day they had recorded two events on their seismographs-a distant nuclear explosion in Nevada and a blast at amine near Centralia, Washington. On another day, they used seismic refraction equipment to locate the depth of bedrock and seismic velocity to it at several locations in West Seattle and in the Seward Park-Brighton district of southeast Seattle. 

  8. The IMACS Cluster Building Survey. I. Description of the Survey and Analysis Methods

    NASA Technical Reports Server (NTRS)

    Oemler Jr., Augustus; Dressler, Alan; Gladders, Michael G.; Rigby, Jane R.; Bai, Lei; Kelson, Daniel; Villanueva, Edward; Fritz, Jacopo; Rieke, George; Poggianti, Bianca M.; Vulcani, Benedetta

    2013-01-01

    The IMACS Cluster Building Survey uses the wide field spectroscopic capabilities of the IMACS spectrograph on the 6.5 m Baade Telescope to survey the large-scale environment surrounding rich intermediate-redshift clusters of galaxies. The goal is to understand the processes which may be transforming star-forming field galaxies into quiescent cluster members as groups and individual galaxies fall into the cluster from the surrounding supercluster. This first paper describes the survey: the data taking and reduction methods. We provide new calibrations of star formation rates (SFRs) derived from optical and infrared spectroscopy and photometry. We demonstrate that there is a tight relation between the observed SFR per unit B luminosity, and the ratio of the extinctions of the stellar continuum and the optical emission lines.With this, we can obtain accurate extinction-corrected colors of galaxies. Using these colors as well as other spectral measures, we determine new criteria for the existence of ongoing and recent starbursts in galaxies.

  9. A Fast Method for Embattling Optimization of Ground-Based Radar Surveillance Network

    NASA Astrophysics Data System (ADS)

    Jiang, H.; Cheng, H.; Zhang, Y.; Liu, J.

    A growing number of space activities have created an orbital debris environment that poses increasing impact risks to existing space systems and human space flight. For the safety of in-orbit spacecraft, a lot of observation facilities are needed to catalog space objects, especially in low earth orbit. Surveillance of Low earth orbit objects are mainly rely on ground-based radar, due to the ability limitation of exist radar facilities, a large number of ground-based radar need to build in the next few years in order to meet the current space surveillance demands. How to optimize the embattling of ground-based radar surveillance network is a problem to need to be solved. The traditional method for embattling optimization of ground-based radar surveillance network is mainly through to the detection simulation of all possible stations with cataloged data, and makes a comprehensive comparative analysis of various simulation results with the combinational method, and then selects an optimal result as station layout scheme. This method is time consuming for single simulation and high computational complexity for the combinational analysis, when the number of stations increases, the complexity of optimization problem will be increased exponentially, and cannot be solved with traditional method. There is no better way to solve this problem till now. In this paper, target detection procedure was simplified. Firstly, the space coverage of ground-based radar was simplified, a space coverage projection model of radar facilities in different orbit altitudes was built; then a simplified objects cross the radar coverage model was established according to the characteristics of space objects orbit motion; after two steps simplification, the computational complexity of the target detection was greatly simplified, and simulation results shown the correctness of the simplified results. In addition, the detection areas of ground-based radar network can be easily computed with the

  10. Comparison of Three Tobacco Survey Methods with College Students: A Case Study

    ERIC Educational Resources Information Center

    James, Delores C. S.; Chen, W. William; Sheu, Jiunn-Jye

    2005-01-01

    The goals of this case study were to: (1) determine the efficiency and effectiveness of three survey methods--postal mail survey, web-based survey, and random in-class administration survey--in assessing tobacco-related attitudes and behaviors among college students and (2) compare the response rate and procedures of these three methods. There was…

  11. A Method for Retrieving Ground Flash Fraction from Satellite Lightning Imager Data

    NASA Technical Reports Server (NTRS)

    Koshak, William J.

    2009-01-01

    A general theory for retrieving the fraction of ground flashes in N lightning observed by a satellite-based lightning imager is provided. An "exponential model" is applied as a physically reasonable constraint to describe the measured optical parameter distributions, and population statistics (i.e., mean, variance) are invoked to add additional constraints to the retrieval process. The retrieval itself is expressed in terms of a Bayesian inference, and the Maximum A Posteriori (MAP) solution is obtained. The approach is tested by performing simulated retrievals, and retrieval error statistics are provided. The ability to retrieve ground flash fraction has important benefits to the atmospheric chemistry community. For example, using the method to partition the existing satellite global lightning climatology into separate ground and cloud flash climatologies will improve estimates of lightning nitrogen oxides (NOx) production; this in turn will improve both regional air quality and global chemistry/climate model predictions.

  12. Dispersed and piled woody residues volumes in coastal Douglas-fir cutblocks determined using high-resolution imagery from a UAV and from ground-based surveys.

    NASA Astrophysics Data System (ADS)

    Trofymow, J. A.; Gougeon, F.

    2015-12-01

    After forest harvest significant amounts of woody residues are left dispersed on site and some subsequently piled and burned. Quantification of residues is required for estimating C budgets, billable waste, harvest efficiency, bioenergy potential and smoke emissions. Trofymow (et al 2014 CJFR) compared remote sensing methods to ground-based waste and residue survey (WRS) methods for residue piles in 4 cutblocks in the Oyster River (OR) area in coastal BC. Compared to geospatial methods using 15cm orthophotos and LiDAR acquired in 2011 by helicopter, the WRS method underestimated pile wood by 30% to 50% while a USFS volume method overestimated pile wood by 50% if site specific packing ratios were not used. A geospatial method was developed in PCI Geomatica to analyze 2-bit images of logs >15cm diameters to determine dispersed wood residues in OR and compare to WRS methods. Across blocks, geospatial and WRS method wood volumes were correlated (R2=0.69), however volumes were 2.5 times larger for the geospatial vs WRS method. Methods for dispersed residues could not be properly compared as individual WRS plots were not georeferenced, only 12 plots were sampled in total, and low-resolution images poorly resolved logs. Thus, a new study in 2 cutblocks in the Northwest Bay (NWB) area acquired 2cm resolution RGB air-photography in 2014-15 using an Aeryon Sky Ranger UAV prior to and after burn pile construction. A total of 57 dispersed WRS plots and 24 WRS pile or accumulation plots were georeferenced and measured. Stero-pairs were used to generate point-clouds for pile bulk volumes. Images processed to 8-bit grey scale are being analyzed with a revised PCI method that better accounts for log overlaps. WRS methods depend on a good sample of plots and accurate determination of stratum (dispersed, roadside, piles, accumulations) areas. Analysis of NWB blocks shows WRS field methods for stratum area differ by 5-20% from that determined using orthophotos. Plot-level wood

  13. Method for the flotation oil extraction of light filth from ground capsicums.

    PubMed

    Thrasher, J J; Colliflower, E J

    1977-05-01

    The present official first action method for ground capsicums, 44.123, was adopted in 1945 and there have been great changes in processing and examination of spices since that time. The proposed method involves isopropanol pretreatment, followed by wet sieving and extraction of the light filth from 60% ethanol with flotation oil. The filter papers were clean and recoveries were good (95%) for 5 different lots of capsicums and annato spiked with insect fragments and rodent hairs. PMID:870482

  14. Ground magnetometer survey in the Valley of Ten Thousand Smokes, Alaska. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Trible, M. C.

    1972-01-01

    A reconnaissance magnetometer survey was conducted with both total- and vertical-field magnetometers. The large, sharp, narrow total magnetic anomalies observed over a zone of relict fumaroles in Broken Mountain Valley showed spectacular agreement with the surficial geology. Such a correlation is a strong indication that accumulations of magnetic minerals have been preserved along these fissure vents at shallow depths. Since large magnetic anomalies were measured near fumarolic markings along all of the traverses, it is proposed that the retention of sublimates along fumarolic vents is common throughout the Valley. The generally concentric contours of the vertical magnetic anomaly at the head of the Valley suggest that the dome of Novarupta is merely the surficial expression of a very massive conical-shaped intrusive centered just northeast of the dome. The magnetometer survey indicates that the pyroclastics in the Valley may be over 150 meters thick. Such an estimate is compatible with the volume of eruptive material needed to compensate for the subsidence surrounding Novarupta as well as a sizable amount of other regional subsidence.

  15. Using Airborne and Ground Electromagnetic Surveys and DC Resistivity Surveys to Delineate a Plume of Conductive Water at an In-Channel Coalbed Methane Produced Water Impoundment Near the Powder River, Wyoming

    NASA Astrophysics Data System (ADS)

    Lipinski, B. A.; Harbert, W.; Hammack, R.; Sams, J.; Veloski, G.; Smith, B. D.

    2004-12-01

    Development of coal bed methane (CBM) in the Powder River Basin of Wyoming and Montana has significantly increased since 1997. Production of CBM involves withdrawing groundwater from the coal bed to lower the hydrostatic pressure thereby allowing methane to desorb from the coal. The water co-produced with CBM is managed by storing it in impoundments until it can infiltrate to the groundwater, be used for beneficial purposes, or be discharged to surface streams. Skewed Reservoir was constructed as a research site to evaluate disposal of CBM water through infiltration ponds constructed by damming ephemeral streams. Geochemical data collected from monitoring wells placed downgradient of the reservoir detected a plume of water with total dissolved solids concentrations an order of magnitude higher than the CBM water stored in the impoundment. Infiltrating CBM water is suspected to have dissolved salts that were present in the unconsolidated materials beneath the reservoir. A geophysical investigation of the Skewed Reservoir area was conducted in July of 2004 to map the horizontal and vertical extent of the plume and to possibly identify the source of solutes to the infiltrating water. The Department of Energy's National Energy Technology Laboratory contracted Fugro Airborne Surveys to fly their RESOLVE frequency domain airborne electromagnetic (AEM) system with 50-m line spacing at the site. A ground investigation was completed at the same time as the airborne survey. Five 2-D dipole-dipole resistivity surveys and one 3-D pole-dipole survey were conducted using the AGI SuperSting R8/IP multi-channel resistivity imaging system. Additionally, ground conductivity measurements were recorded along each resistivity line using a Geophex GEM-2 multi-frequency ground conductivity meter. All geoelectrical measurements were inverted to obtain the subsurface conductivity distribution. Inversions were constrained using results of downhole borehole induction logs. Results were

  16. Two-step adaptive extraction method for ground points and breaklines from lidar point clouds

    NASA Astrophysics Data System (ADS)

    Yang, Bisheng; Huang, Ronggang; Dong, Zhen; Zang, Yufu; Li, Jianping

    2016-09-01

    The extraction of ground points and breaklines is a crucial step during generation of high quality digital elevation models (DEMs) from airborne LiDAR point clouds. In this study, we propose a novel automated method for this task. To overcome the disadvantages of applying a single filtering method in areas with various types of terrain, the proposed method first classifies the points into a set of segments and one set of individual points, which are filtered by segment-based filtering and multi-scale morphological filtering, respectively. In the process of multi-scale morphological filtering, the proposed method removes amorphous objects from the set of individual points to decrease the effect of the maximum scale on the filtering result. The proposed method then extracts the breaklines from the ground points, which provide a good foundation for generation of a high quality DEM. Finally, the experimental results demonstrate that the proposed method extracts ground points in a robust manner while preserving the breaklines.

  17. Cross-cultural issues in space operations: A survey study among ground personnel of the European Space Agency

    NASA Astrophysics Data System (ADS)

    Sandal, Gro Mjeldheim; Manzey, Dietrich

    2009-12-01

    Today's space operations involve co-working of people with different ethnical, professional and organisational backgrounds. The aim of this study was to examine the implications of cultural diversity for efficient collaboration within the European Space Agency (ESA), and between ESA employees and representatives from other agencies. ESA employees from European countries ( N=576) answered to the CULT Ground Survey. The results showed that differences in relation to leadership and decision making were the most important issues thought to interfere with efficient co-working within ESA, and between ESA employees and colleagues from other agencies. Employees who collaborated with more than three nationalities within ESA indicated most challenges in co-working due to differences in compliance, behavioural norms and competitiveness. Challenges in co-working differed between agencies, and these differences were consistent with value differences in the national populations. The results may have applied value for training of European employees working in international space program teams.

  18. Prediction of Ground Surface Temperature and Soil Moisture Content by the Force-Restore Method

    NASA Astrophysics Data System (ADS)

    Hu, Zhenglin; Islam, Shafiqul

    1995-10-01

    The parsimony and computational efficiency offered by the force-restore approximation of the diffusion equation have motivated its widespread application in modeling ground surface temperature. Different assumptions regarding the definition of ground surface temperature have resulted in different versions of the force-restore method. Here, four existing versions of the force-restore method for ground surface temperature are compared and contrasted. An improved version of the force-restore method is developed by minimizing the error produced by the force-restore approximation of the heat diffusion equation. The proposed model performs well for the physically realistic ranges of scaled soil thickness and reproduces amplitude and phase that are quite close to the exact solution of the diffusion equation under a single periodic forcing. It is shown that neglect of higher harmonics can produce appreciable errors in the force-restore method if the upper soil thickness is less than the damping depth of the diurnal forcing. The success of the force-restore approximation in modeling ground surface temperature has prompted its application in the prediction of soil moisture content. However, extension of the force-restore method for the prediction of soil moisture content is not straightforward. There are two major difficulties in modeling soil moisture content by the force-restore method. One is the situation-dependent relative importance of the suction term and gravity term in the Richards equation and the other is the choice of state variable, moisture content versus suction head, in the solution of the force-restore method for soil moisture prediction. Both of these could produce appreciable errors in the force-restore treatment of soil moisture evolution.

  19. Scattered data interpolation methods for electronic imaging systems: a survey

    NASA Astrophysics Data System (ADS)

    Amidror, Isaac

    2002-04-01

    Numerous problems in electronic imaging systems involve the need to interpolate from irregularly spaced data. One example is the calibration of color input/output devices with respect to a common intermediate objective color space, such as XYZ or L*a*b*. In the present report we survey some of the most important methods of scattered data interpolation in two-dimensional and in three-dimensional spaces. We review both single-valued cases, where the underlying function has the form f: R2 yields R or f: R3 yields R, and multivalued cases, where the underlying function is f: R2 yields R2 or f: R3 yields R3. The main methods we review include linear triangular (or tetrahedral) interpolation, cubic triangular (Clough--Tocher) interpolation, triangle based blending interpolation, inverse distance weighted methods, radial basis function methods, and natural neighbor interpolation methods. We also review one method of scattered data fitting, as an illustration to the basic differences between scattered data interpolation and scattered data fitting.

  20. Methods for locating ground faults and insulation degradation condition in energy conversion systems

    DOEpatents

    Agamy, Mohamed; Elasser, Ahmed; Galbraith, Anthony William; Harfman Todorovic, Maja

    2015-08-11

    Methods for determining a ground fault or insulation degradation condition within energy conversion systems are described. A method for determining a ground fault within an energy conversion system may include, in part, a comparison of baseline waveform of differential current to a waveform of differential current during operation for a plurality of DC current carrying conductors in an energy conversion system. A method for determining insulation degradation within an energy conversion system may include, in part, a comparison of baseline frequency spectra of differential current to a frequency spectra of differential current transient at start-up for a plurality of DC current carrying conductors in an energy conversion system. In one embodiment, the energy conversion system may be a photovoltaic system.

  1. Occurrence of selected radionuclides in ground water used for drinking water in the United States; a reconnaissance survey, 1998

    USGS Publications Warehouse

    Focazio, Michael J.; Szabo, Zoltan; Kraemer, Thomas F.; Mullin, Ann H.; Barringer, Thomas H.; dePaul, Vincent T.

    2001-01-01

    The U.S. Geological Survey, in collaboration with the U.S. Environmental Protection Agency, the American Water Works Association, and the American Water Works Service Company, completed a targeted national reconnaissance survey of selected radionuclides in public ground-water supplies. Radionuclides analyzed included radium-224 (Ra-224), radium-226 (Ra-226), radium-228 (Ra-228), polonium-210 (Po-210) and lead-210 (Pb-210).This U.S. Geological Survey reconnaissance survey focused intentionally on areas with known or suspected elevated concentrations of radium in ground water to determine if Ra-224 was also present in the areas where other isotopes of radium had previously been detected and to determine the co-occurrence characteristics of the three radium isotopes (Ra-224, Ra-226, and Ra-228) in those areas. Ninety-nine raw-water samples (before water treatment) were collected once over a 6-month period in 1998 and 1999 from wells (94 of which are used for public drinking water) in 27 States and 8 physiographic provinces. Twenty-one of the 99 samples exceeded the current U.S. Environmental Protection Agency drinking-water maximum contaminant level of 5 picocuries per liter (pCi/L) for combined radium (Ra-226 + Ra-228). Concentrations of Ra-224 were reported to exceed 1 pCi/L in 30 percent of the samples collected, with a maximum concentration of 73.6 pCi/L measured in water from a nontransient, noncommunity, public-supply well in Maryland. Radium-224 concentrations generally were higher than those of the other isotopes of radium. About 5 percent of the samples contained concentrations of Ra-224 greater than 10 pCi/L, whereas only 2 percent exceeded 10 pCi/L for either Ra-226 or Ra-228. Concentrations of Ra-226 greater than 1 pCi/L were reported in 33 percent of the samples, with a maximum concentration of 16.9 pCi/L measured in water from a public-supply well in Iowa. Concentrations of Ra-228 greater than 1 pCi/L were reported in 22 samples, with a maximum

  2. Calibrated propensity score method for survey nonresponse in cluster sampling

    PubMed Central

    Kim, Jae Kwang; Kwon, Yongchan; Paik, Myunghee Cho

    2016-01-01

    Weighting adjustment is commonly used in survey sampling to correct for unit nonresponse. In cluster sampling, the missingness indicators are often correlated within clusters and the response mechanism is subject to cluster-specific nonignorable missingness. Based on a parametric working model for the response mechanism that incorporates cluster-specific nonignorable missingness, we propose a method of weighting adjustment. We provide a consistent estimator of the mean or totals in cases where the study variable follows a generalized linear mixed-effects model. The proposed method is robust in the sense that the consistency of the estimator does not require correct specification of the functional forms of the response and outcome models. A consistent variance estimator based on Taylor linearization is also proposed. Numerical results, including a simulation and a real-data application, are presented.

  3. Analytic Perturbation Method for Estimating Ground Flash Fraction from Satellite Lightning Observations

    NASA Technical Reports Server (NTRS)

    Koshak, William; Solakiewicz, Richard

    2013-01-01

    An analytic perturbation method is introduced for estimating the lightning ground flash fraction in a set of N lightning flashes observed by a satellite lightning mapper. The value of N is large, typically in the thousands, and the observations consist of the maximum optical group area produced by each flash. The method is tested using simulated observations that are based on Optical Transient Detector (OTD) and Lightning Imaging Sensor (LIS) data. National Lightning Detection NetworkTM (NLDN) data is used to determine the flash-type (ground or cloud) of the satellite-observed flashes, and provides the ground flash fraction truth for the simulation runs. It is found that the mean ground flash fraction retrieval errors are below 0.04 across the full range 0-1 under certain simulation conditions. In general, it is demonstrated that the retrieval errors depend on many factors (i.e., the number, N, of satellite observations, the magnitude of random and systematic measurement errors, and the number of samples used to form certain climate distributions employed in the model).

  4. Monitoring soil moisture dynamics via ground-penetrating radar survey of agriculture fields after irrigation

    NASA Astrophysics Data System (ADS)

    Muro, G.

    2015-12-01

    It is possible to examine the quality of ground-penetrating radar (GPR) as a measure of soil moisture content in the shallow vadose zone, where roots are most abundant and water conservation best management practices are critical in active agricultural fields. By analyzing temporal samplings of 100 Mhz reflection profiles and common-midpoint (CMP) soundings over a full growing season, the variability of vertical soil moisture distribution directly after irrigation events are characterized throughout the lifecycle of a production crop. Reflection profiles produce high-resolution travel time data and summed results of CMP sounding data provide sampling depth estimates for the weak, but coherent reflections amid strong point scatterers. The high ratio of clay in the soil limits the resolution of downward propagation of infiltrating moisture after irrigation; synthetic data analysis compared against soil moisture lysimeter logs throughout the profile allow identification of the discrete soil moisture content variation in the measured GPR data. The nature of short duration irrigation events, evapotranspiration, and drainage behavior in relation to root depths observed in the GPR temporal data allow further examination and comparison with the variable saturation model HYDRUS-1D. After retrieving soil hydraulic properties derived from laboratory measured soil samples and simplified assumptions about boundary conditions, the project aims to achieve good agreement between simulated and measured soil moisture profiles without the need for excessive model calibration for GPR-derived soil moisture estimates in an agricultural setting.

  5. Retirement on grounds of ill health: cross sectional survey in six organisations in United Kingdom.

    PubMed Central

    Poole, C. J.

    1997-01-01

    OBJECTIVE: To assess the process and outcome of retirement due to ill health in six large organisations. DESIGN: Cross sectional study of the rate of retirement due to ill health by age, sex, and length of service. Principal diagnoses by age and length of service were also compared. SETTING: Four public and two private large employers in the United Kingdom. MAIN OUTCOME MEASURES: Rates of retirement on the grounds of ill health by age, sex, and length of service of employees contributing to pension schemes. RESULTS: Rates of ill health retirement varied from 20 to 250 per 10,000 contributing members, and in two organisations the rate varied geographically within the same organisation. In the two organisations that provided data by sex, women retired at a greater rate than men under age 40 and over age 50. In four organisations the modal age or length of service coincided with enhancements in benefits. In the four that provided information on diagnoses, musculoskeletal and minor psychiatric illnesses were the most common reasons for retirement. CONCLUSION: The granting of ill health retirement benefits may not be determined by illness. There is a need for some employers and pension schemes to improve their processes for granting benefits. Doctors should be wary of conflicts of interest and work to guidelines when they advise pension schemes about the merits of an application for benefits. PMID:9099115

  6. Three-dimensional resistivity characterization of a coastal area: Application of Grounded Electrical-Source Airborne Transient Electromagnetic (GREATEM) survey data from Kujukuri Beach, Japan

    NASA Astrophysics Data System (ADS)

    Abd Allah, Sabry; Mogi, Toru; Ito, Hisatoshi; Jomori, Akira; Yuuki, Youichi; Fomenko, Elena; Kiho, Kenzo; Kaieda, Hideshi; Suzuki, Koichi; Tsukuda, Kazuhiro

    2013-12-01

    An airborne electromagnetic (AEM) survey using the Grounded Electrical-Source Airborne Transient Electromagnetic (GREATEM) system was conducted over the Kujukuri coastal plain in southeast Japan to assess the system's ability to accurately describe the geological structure beneath shallow seawater. To obtain high-quality data with an optimized signal-to-noise ratio, a series of data processing techniques were used to obtain the final transient response curves from the field survey data. These steps included movement correction, coordinate transformation, the removal of local noise, data stacking, and signal portion extraction. We performed numerical forward modeling to generate a three-dimensional (3D) resistivity structure model from the GREATEM data. This model was developed from an initial one-dimensional (1D) resistivity structure that was also inverted from the GREATEM field survey data. We modified a 3D electromagnetic forward-modeling scheme based on a finite-difference staggered-grid method and used it to calculate the response of the 3D resistivity model along each survey line. We verified the model by examining the fit of the magnetic-transient responses between field data and the 3D forward-model computed data, the latter of which were convolved with the measured system responses of the corresponding data set. The inverted 3D resistivity structures showed that the GREATEM system has the capability to map resistivity structures as far as 800 m offshore and as deep as 300-350 m underground in coastal areas of relatively shallow seawater depth (5-10 m).

  7. Evolution of Ground Deformation Zone on Normal Fault Using Distinct Element Method and Centrifuge Modeling

    NASA Astrophysics Data System (ADS)

    Lyu, Jhen-Yi; Chang, Yu-Yi; Lee, Chung-Jung; Lin, Ming-Lang

    2015-04-01

    The depth and character of the overlying earth deposit contribute to fault rupture path. For cohesive soil, for instance, clay, tension cracks on the ground happen during faulting, limiting the propagation of fracture in soil mass. The cracks propagate downwards while the fracture induced by initial displacement of faulting propagates upwards. The connection of cracks and fracture will form a plane that is related to tri-shear zone. However the mechanism of the connection has not been discussed thoroughly. By obtaining the evolution of ground deformation zone we can understand mechanism of fault propagation and crack-fracture connection. A series of centrifuge tests and numerical modeling are conducted at this study with acceleration conditions of 40g, 50g, 80g and dip angle of 60° on normal faulting. The model is with total overburden thick, H, 0.2m, vertical displacement of moving wall, ∆H. At the beginning, hanging wall and the left-boundary wall moves along the plane of fault. When ∆H/H equals to 25%, both of the walls stop moving. We then can calculate the width of ground deformation in different depth of each model by a logic method. Models of this study consist of two different type overburden material to simulate sand and clay in situ. Different from finite element method, with application of distinct element method the mechanism of fault propagation in soil mass and the development of ground deformation zone can be observed directly in numerical analysis of faulting. The information of force and deformation in the numerical model are also easier to be obtained than centrifuge modeling. Therefore, we take the results of centrifuge modeling as the field outcrop then modify the micro-parameter of numerical analysis to make sure both of them have the same attitude. The results show that in centrifuge modeling narrower ground deformation zone appears in clayey overburden model as that of sandy overburden model is wider on footwall. Increasing the strength

  8. Efficient numerical methods for computing ground states of spin-1 Bose–Einstein condensates based on their characterizations

    SciTech Connect

    Bao, Weizhu; Chern, I-Liang; Zhang, Yanzhi

    2013-11-15

    In this paper, we propose efficient numerical methods for computing ground states of spin-1 Bose–Einstein condensates (BECs) with/without the Ioffe–Pritchard magnetic field B(x). When B(x)≠0, a numerical method is introduced to compute the ground states and it is also applied to study properties of ground states. Numerical results suggest that the densities of m{sub F}=±1 components in ground states are identical for any nonzero B(x). In particular, if B(x)≡B≠0 is a constant, the ground states satisfy the single-mode approximation. When B(x)≡0, efficient and simpler numerical methods are presented to solve the ground states of spin-1 BECs based on their ferromagnetic/antiferromagnetic characterizations. Numerical simulations show that our methods are more efficient than those in the literature. In addition, some conjectures are made from our numerical observations.

  9. The application of ground-penetrating radar method for detecting buried human bodies on the Cikutra graveyard, Indonesia

    NASA Astrophysics Data System (ADS)

    Aditama, Iqbal Fauzi; Syaifullah, Khalid Istiqlal; Saputera, Durra Handri; Widodo

    2015-04-01

    Ground-penetrating radar (GPR) can be used to study shallow subsurface of the earth. GPR can be utilized to detect buried human bodies that suffered landslides or buried by other causes. A detailed ground-penetrating survey was conducted in the Cikutra graveyard, Bandung on a corpse buried two weeks from the time of the survey. Processing the data was carried out to filter out noise and to improve the resolution. The radar profiles from this survey produced hyperbolic reflections, emanated from the corpse. The hyperbolic reflection was strongest in the abdomen region compared to the head and the legs of the corpse. The result of data processing shows similarity between data from the survey and the actual location of the human body. We obtained the hyperbolic reflection at around 1.5 meters depth which is consistent with the depth of the buried corpse.

  10. A Method of Ground Simulation of Physiological Effects of Hypogravity on Humans.

    PubMed

    Baranov, M V; Katuntsev, V P; Shpakov, A V; Baranov, V M

    2016-01-01

    A novel method of ground simulation in humans of physiological effects induced by the stay on the surface of celestial bodies with hypogravity was developed and successfully tested. This method is based on the change of gravity force angle, which decreases the gravitational component of the blood hydrostatic pressure characteristic of human vertical posture on the Earth and the load-weight onto the locomotor apparatus to the lower values expected at celestial bodies with hypogravity. The methodological requirements for ground simulation of the physiological effects of lunar gravity on human body are specified and substantiated by theoretical calculations. The experimental study revealed redistribution of liquid media in the human organism, functional changes in the cardiorespiratory system, and a decrease in the load-weight applied to the locomotor apparatus. PMID:26742752

  11. A new fabrication method for precision antenna reflectors for space flight and ground test

    NASA Technical Reports Server (NTRS)

    Sharp, G. Richard; Wanhainen, Joyce S.; Ketelsen, Dean A.

    1990-01-01

    The use of higher frequencies on communications satellites has led to the requirement for increasingly precise antenna reflectors for use in space. Typical industry fabrication methods for space antenna reflectors employ successive molding techniques for reflector face sheets and a final fit-up to a master mold in order to achieve the required accuracies. However, new missions at much higher frequencies will require greater accuracies than may be achievable using these present methods. A new approach for the fabrication of ground-test antenna reflectors is to machine the reflective surface into a stainless steel and fiberglass composite structure. A 2.7-m diameter ground-test antenna reflector fabricated using this method has an accuracy of better than 0.013 mm (0.0005 in.) rms. A similar design concept for a solid surface reflector for use on spacecraft would involve fabrication in a similar manner but using space-qualified materials. This report describes the design, analysis, and fabrication of the 2.7-m-diameter precision antenna reflector for antenna ground test and the extension of this technology to precision space antenna reflectors.

  12. A new fabrication method for precision antenna reflectors for space flight and ground test

    NASA Technical Reports Server (NTRS)

    Sharp, G. Richard; Wanhainen, Joyce S.; Ketelsen, Dean A.

    1991-01-01

    Communications satellites are using increasingly higher frequencies that require increasingly precise antenna reflectors for use in space. Traditional industry fabrication methods for space antenna reflectors employ successive modeling techniques using high- and low-temperature molds for reflector face sheets and then a final fit-up of the completed honeycomb sandwich panel antenna reflector to a master pattern. However, as new missions are planned at much higher frequencies, greater accuracies will be necessary than are achievable using these present methods. A new approach for the fabrication of ground-test solid-surface antenna reflectors is to build a rigid support structure with an easy-to-machine surface. This surface is subsequently machined to the desired reflector contour and coated with a radio-frequency-reflective surface. This method was used to fabricate a 2.7-m-diameter ground-test antenna reflector to an accuracy of better than 0.013 mm (0.0005 in.) rms. A similar reflector for use on spacecraft would be constructed in a similar manner but with space-qualified materials. The design, analysis, and fabrication of the 2.7-m-diameter precision antenna reflector for antenna ground tests and the extension of this technology to precision, space-based antenna reflectors are described.

  13. Borehole survey method and apparatus for drilling substantially horizontal boreholes

    SciTech Connect

    Trowsdale, L.S.

    1982-11-30

    A borehole survey method and apparatus are claimed for use in drilling substantially horizontal boreholes through a mineral deposit wherein a dip accelerometer, a roll accelerometer assembly and a fluxgate are disposed near the drill bit, which is mounted on a bent sub, and connected to a surface computation and display unit by a cable which extends through the drill string. The dip angle of the borehole near the drill bit, the azimuth of the borehole near the drill bit and the roll angle or orientation of the bent sub are measured and selectively displayed at the surface while the drill string is in the borehole for utilization in guiding the drill bit through the mineral deposit along a predetermined path.

  14. A survey on methods of design features identification

    NASA Astrophysics Data System (ADS)

    Grabowik, C.; Kalinowski, K.; Paprocka, I.; Kempa, W.

    2015-11-01

    currently identified feature. In the IFR method system designer defines a set of features and sets a collection of recognition process parameters. It allows to unambiguously identifying individual features in automatic or semiautomatic way directly in CAD system or in an external application to which the part model might be transferred. Additionally a user is able to define non-geometrical information such as: overall dimensions, surface roughness etc. In this paper a survey on methods of features identification and recognition is presented especially in context of AFR methods.

  15. 30 CFR 77.701-1 - Approved methods of grounding of equipment receiving power from ungrounded alternating current...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... receiving power from ungrounded alternating current power systems. 77.701-1 Section 77.701-1 Mineral...-1 Approved methods of grounding of equipment receiving power from ungrounded alternating current... receiving power from ungrounded alternating current power systems, the following methods of grounding...

  16. 30 CFR 77.701-1 - Approved methods of grounding of equipment receiving power from ungrounded alternating current...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... receiving power from ungrounded alternating current power systems. 77.701-1 Section 77.701-1 Mineral...-1 Approved methods of grounding of equipment receiving power from ungrounded alternating current... receiving power from ungrounded alternating current power systems, the following methods of grounding...

  17. 30 CFR 77.701-1 - Approved methods of grounding of equipment receiving power from ungrounded alternating current...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... receiving power from ungrounded alternating current power systems. 77.701-1 Section 77.701-1 Mineral...-1 Approved methods of grounding of equipment receiving power from ungrounded alternating current... receiving power from ungrounded alternating current power systems, the following methods of grounding...

  18. 30 CFR 77.701-1 - Approved methods of grounding of equipment receiving power from ungrounded alternating current...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... receiving power from ungrounded alternating current power systems. 77.701-1 Section 77.701-1 Mineral...-1 Approved methods of grounding of equipment receiving power from ungrounded alternating current... receiving power from ungrounded alternating current power systems, the following methods of grounding...

  19. 30 CFR 77.701-1 - Approved methods of grounding of equipment receiving power from ungrounded alternating current...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... receiving power from ungrounded alternating current power systems. 77.701-1 Section 77.701-1 Mineral...-1 Approved methods of grounding of equipment receiving power from ungrounded alternating current... receiving power from ungrounded alternating current power systems, the following methods of grounding...

  20. Surveying abandoned mine shafts with Remote Radio Transmitter EM methods and Selfpotential

    NASA Astrophysics Data System (ADS)

    Bosch, F. P.; Gurk, M.

    2009-04-01

    Abandoned near subsurface mining constructions from the 19th and early 20th century in urbanized areas placed upon former ore mines near the city of Aachen (Germany), as well as in many other regions of the world, provide hazardous risks concerning possible collapses. In many cases, the exact locations of such constructions are not known anymore. For instance, to map covered shafts of one meter diameter on large survey areas, high resolution methods with rapid measurement progress are necessary. Enhanced developments of the traditional Very Low Frequency (VLF) technique such as VLF-gradient and Radiomagnetotellurics (RMT) fulfill these requirements. Continuous ground-contactless VLF-gradient survey quickly provides maps indicating the lateral electric resistivity heterogeneity distribution. Inversions of RMT data provide 2D-resistivity-depth sections and also the interpretation of Self-Potential data gives information about the nature of the VLF-gradient anomalies. The successful combination of the three methods for detecting mineshafts near to the city if Aachen is presented for both an electromagnetic undisturbed and noisy location.

  1. Testing alternative ground water models using cross-validation and other methods

    USGS Publications Warehouse

    Foglia, L.; Mehl, S.W.; Hill, M.C.; Perona, P.; Burlando, P.

    2007-01-01

    Many methods can be used to test alternative ground water models. Of concern in this work are methods able to (1) rank alternative models (also called model discrimination) and (2) identify observations important to parameter estimates and predictions (equivalent to the purpose served by some types of sensitivity analysis). Some of the measures investigated are computationally efficient; others are computationally demanding. The latter are generally needed to account for model nonlinearity. The efficient model discrimination methods investigated include the information criteria: the corrected Akaike information criterion, Bayesian information criterion, and generalized cross-validation. The efficient sensitivity analysis measures used are dimensionless scaled sensitivity (DSS), composite scaled sensitivity, and parameter correlation coefficient (PCC); the other statistics are DFBETAS, Cook's D, and observation-prediction statistic. Acronyms are explained in the introduction. Cross-validation (CV) is a computationally intensive nonlinear method that is used for both model discrimination and sensitivity analysis. The methods are tested using up to five alternative parsimoniously constructed models of the ground water system of the Maggia Valley in southern Switzerland. The alternative models differ in their representation of hydraulic conductivity. A new method for graphically representing CV and sensitivity analysis results for complex models is presented and used to evaluate the utility of the efficient statistics. The results indicate that for model selection, the information criteria produce similar results at much smaller computational cost than CV. For identifying important observations, the only obviously inferior linear measure is DSS; the poor performance was expected because DSS does not include the effects of parameter correlation and PCC reveals large parameter correlations. ?? 2007 National Ground Water Association.

  2. The effect of survey method on survey participation: Analysis of data from the Health Survey for England 2006 and the Boost Survey for London

    PubMed Central

    2010-01-01

    Background There is a need for local level health data for local government and health bodies, for health surveillance and planning and monitoring of policies and interventions. The Health Survey for England (HSE) is a nationally-representative survey of the English population living in private households, but sub-national analyses can be performed only at a regional level because of sample size. A boost of the HSE was commissioned to address the need for local level data in London but a different mode of data collection was used to maximise participant numbers for a given cost. This study examines the effects on survey and item response of the different survey modes. Methods Household and individual level data are collected in HSE primarily through interviews plus individual measures through a nurse visit. For the London Boost, brief household level data were collected through interviews and individual level data through a longer self-completion questionnaire left by the interviewer and collected later. Sampling and recruitment methods were identical, and both surveys were conducted by the same organisation. There was no nurse visit in the London Boost. Data were analysed to assess the effects of differential response rates, item non-response, and characteristics of respondents. Results Household response rates were higher in the 'Boost' (61%) than 'Core' (HSE participants in London) sample (58%), but the individual response rate was considerably higher in the Core (85%) than Boost (65%). There were few differences in participant characteristics between the Core and Boost samples, with the exception of ethnicity and educational qualifications. Item non-response was similar for both samples, except for educational level. Differences in ethnicity were corrected with non-response weights, but differences in educational qualifications persisted after non-response weights were applied. When item non-response was added to those reporting no qualification, participants

  3. Characteristics of Earthquake Ground Motion in Tapachula, Chiapas (mexico) from Empirical and Theorical Methods

    NASA Astrophysics Data System (ADS)

    Vidal, F.; Alguacil, G.; Rodríguez, L.; Navarro, M.; Ruiz, A.; Aguirre, J.; Acosta, M.; Gonzalez, R.; Mora, J.; Reyes, M.

    2013-05-01

    The high seismic hazard level of Tapachula city (Chiapas, Mexico) requires a better understanding of the characteristics of earthquake ground motion to implement risk reduction policies in this urban area. A map of ground predominant period estimated with Nakamura technique already shows four different zones: the largest one in the downtown with 0.2-0.4s, two small zones (concentric to the previous one) of 0.4-0.7s and 0.7-0.9 s, respectively, and the smallest zone (on the edge of the city) with the higher values 0.9-1.1s. During 44 days more than 220 events were recorded by a temporal seismic network installed by the UNAM at 6 sites distributed in Tapachula. The magnitude Mw and hypocentral distance of the events were reassessed and range from 3.3 to 4.5 and 60 to 190 km, respectively. After selecting the accelerograms with the best signal/noise ratio, a set of key engineering ground-motion parameters such as peak values of strong motion, acceleration and velocity response spectra, Arias intensity, cumulative absolute velocity, relative significant duration, the Housner spectrum-intensity, the energy input spectrum and H/V spectral ratio were calculated for the selected events. The ground-motion prediction equations (GMPE) of each parameter as function of magnitude and distance were also estimated. On the other hand, synthetic seismic traces were obtained at each station site after modeling a seismic source of magnitude 7.2 by using the empirical Green's function method. Thus, a shake-map scenario was generated for an earthquake similar to that of the September 10, 1993. The parameters here obtained show different shake levels and frequency content at each site. All sites present amplification for 0.25 and 0.5 s. TACA, TAPP y TATC stations, located near the two rivers bordering Tapachula, are those with the largest ground amplification. The characteristics of strong ground motion obtained from synthetic accelerograms are in agreement with those from the empirical

  4. Direction and Integration of Experimental Ground Test Capabilities and Computational Methods

    NASA Technical Reports Server (NTRS)

    Dunn, Steven C.

    2016-01-01

    This paper groups and summarizes the salient points and findings from two AIAA conference panels targeted at defining the direction, with associated key issues and recommendations, for the integration of experimental ground testing and computational methods. Each panel session utilized rapporteurs to capture comments from both the panel members and the audience. Additionally, a virtual panel of several experts were consulted between the two sessions and their comments were also captured. The information is organized into three time-based groupings, as well as by subject area. These panel sessions were designed to provide guidance to both researchers/developers and experimental/computational service providers in defining the future of ground testing, which will be inextricably integrated with the advancement of computational tools.

  5. Electron excitation from ground state to first excited state: Bohmian mechanics method

    NASA Astrophysics Data System (ADS)

    Yang, Song; Shuang, Zhao; Fu-Ming, Guo; Yu-Jun, Yang; Su-Yu, Li

    2016-03-01

    The excitation process of electrons from the ground state to the first excited state via the resonant laser pulse is investigated by the Bohmian mechanics method. It is found that the Bohmian particles far away from the nucleus are easier to be excited and are excited firstly, while the Bohmian particles in the ground state is subject to a strong quantum force at a certain moment, being excited to the first excited state instantaneously. A detailed analysis for one of the trajectories is made, and finally we present the space and energy distribution of 2000 Bohmian particles at several typical instants and analyze their dynamical process at these moments. Project supported by the Doctoral Research Start-up Funding of Northeast Dianli University, China (Grant No. BSJXM-201332), the National Natural Science Foundation of China (Grant Nos. 11547114, 11534004, 11474129, 11274141, 11447192, and 11304116), and the Graduate Innovation Fund of Jilin University, China (Grant No. 2015091).

  6. Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Benchmarks for Ground-State Properties.

    PubMed

    Dral, Pavlo O; Wu, Xin; Spörkel, Lasse; Koslowski, Axel; Thiel, Walter

    2016-03-01

    The semiempirical orthogonalization-corrected OMx methods (OM1, OM2, and OM3) go beyond the standard MNDO model by including additional interactions in the electronic structure calculation. When augmented with empirical dispersion corrections, the resulting OMx-Dn approaches offer a fast and robust treatment of noncovalent interactions. Here we evaluate the performance of the OMx and OMx-Dn methods for a variety of ground-state properties using a large and diverse collection of benchmark sets from the literature, with a total of 13035 original and derived reference data. Extensive comparisons are made with the results from established semiempirical methods (MNDO, AM1, PM3, PM6, and PM7) that also use the NDDO (neglect of diatomic differential overlap) integral approximation. Statistical evaluations show that the OMx and OMx-Dn methods outperform the other methods for most of the benchmark sets. PMID:26771261

  7. Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Benchmarks for Ground-State Properties

    PubMed Central

    2016-01-01

    The semiempirical orthogonalization-corrected OMx methods (OM1, OM2, and OM3) go beyond the standard MNDO model by including additional interactions in the electronic structure calculation. When augmented with empirical dispersion corrections, the resulting OMx-Dn approaches offer a fast and robust treatment of noncovalent interactions. Here we evaluate the performance of the OMx and OMx-Dn methods for a variety of ground-state properties using a large and diverse collection of benchmark sets from the literature, with a total of 13035 original and derived reference data. Extensive comparisons are made with the results from established semiempirical methods (MNDO, AM1, PM3, PM6, and PM7) that also use the NDDO (neglect of diatomic differential overlap) integral approximation. Statistical evaluations show that the OMx and OMx-Dn methods outperform the other methods for most of the benchmark sets. PMID:26771261

  8. COMPARISON OF METHODS FOR ESTIMATING GROUND-WATER PUMPAGE FOR IRRIGATION.

    USGS Publications Warehouse

    Frenzel, Steven A.

    1985-01-01

    Ground-water pumpage for irrigation was measured at 32 sites on the eastern Snake River Plain in southern Idaho during 1983. Pumpage at these sites also was estimated by three commonly used methods, and pumpage estimates were compared to measured values to determine the accuracy of each estimate. Statistical comparisons of estimated and metered pumpage using an F-test showed that only estimates made using the instantaneous discharge method were not significantly different ( alpha equals 0. 01) from metered values. Pumpage estimates made using the power consumption method reflect variability in pumping efficiency among sites. Pumpage estimates made using the crop-consumptive use method reflect variability in water-management practices. Pumpage estimates made using the instantaneous discharge method reflect variability in discharges at each site during the irrigation season.

  9. Hybrid Genetic Algorithm - Local Search Method for Ground-Water Management

    NASA Astrophysics Data System (ADS)

    Chiu, Y.; Nishikawa, T.; Martin, P.

    2008-12-01

    Ground-water management problems commonly are formulated as a mixed-integer, non-linear programming problem (MINLP). Relying only on conventional gradient-search methods to solve the management problem is computationally fast; however, the methods may become trapped in a local optimum. Global-optimization schemes can identify the global optimum, but the convergence is very slow when the optimal solution approaches the global optimum. In this study, we developed a hybrid optimization scheme, which includes a genetic algorithm and a gradient-search method, to solve the MINLP. The genetic algorithm identifies a near- optimal solution, and the gradient search uses the near optimum to identify the global optimum. Our methodology is applied to a conjunctive-use project in the Warren ground-water basin, California. Hi- Desert Water District (HDWD), the primary water-manager in the basin, plans to construct a wastewater treatment plant to reduce future septic-tank effluent from reaching the ground-water system. The treated wastewater instead will recharge the ground-water basin via percolation ponds as part of a larger conjunctive-use strategy, subject to State regulations (e.g. minimum distances and travel times). HDWD wishes to identify the least-cost conjunctive-use strategies that control ground-water levels, meet regulations, and identify new production-well locations. As formulated, the MINLP objective is to minimize water-delivery costs subject to constraints including pump capacities, available recharge water, water-supply demand, water-level constraints, and potential new-well locations. The methodology was demonstrated by an enumerative search of the entire feasible solution and comparing the optimum solution with results from the branch-and-bound algorithm. The results also indicate that the hybrid method identifies the global optimum within an affordable computation time. Sensitivity analyses, which include testing different recharge-rate scenarios, pond

  10. Further Tests of the Seismo-Lineament Method for Recognizing Seismogenic Faults at the Ground Surface

    NASA Astrophysics Data System (ADS)

    Millard, M. A.; Campbell, R. D.; Lindsay, R. D.; Secrest, S. H.; Cronin, V. S.

    2007-05-01

    The importance of locating the surface trace of faults that can produce earthquakes is self-evident, particularly in California where avoidance of ground-rupture hazards is a legal requirement. We have developed a method that utilizes earthquake focal mechanism solutions coupled with field reconnaissance to locate the surface trace of probable seismogenic faults. We project a fault-plane solution from the boundaries of the uncertainty region around the earthquake focus to the surface of a DEM to define a seismo-lineament -- a zone within which the surface trace of the fault associated with the earthquake is likely to be located. Field work is then undertaken to evaluate the hypothesis that a seismogenic fault exists within the seismo-lineament. If a fault is found within the seismo-lineament, the fault’s orientation and direction of slip are statistically compared with the orientation and slip data from the fault-plane solution to complete the spatial correlation of the fault with the earthquake. To evaluate the effectiveness of this procedure, we selected 6 historic earthquakes that caused fault displacement of the ground surface and used the seismo-lineament method to indicate the probable location of the surface trace of the fault. Earthquakes analyzed in this study include the Parkfield (2004, M6), Denali (2002, M7.9), Hector Mine (1999, M7.1), Superstition Hills (1987, M6.2 and M6.6), and Borah Peak (1983, M7.3) earthquakes. In all 6 test cases, the actual ground-rupture zone associated with the main shock was located within the seismo-lineament. In addition to using focal-mechanism solutions associated with the main shocks to define seismo-lineaments, we have used data from several major aftershocks associated with these events. Seismo-lineaments defined by aftershocks also coincided with the surface trace of the seismogenic fault. Based on results from this study, the seismo-lineament method is likely to be useful in identifying probable seismogenic faults

  11. Hierarchical scheduling method of UAV resources for emergency surveying

    NASA Astrophysics Data System (ADS)

    Zhang, Junxiao; Zhu, Qing; Shen, Fuqiang; Miao, Shuangxi; Cao, Zhenyu; Weng, Qiqiang

    2015-12-01

    Traditional mission scheduling methods are unable to meet the timeliness requirements of emergency surveying. Different size and overlaps of different missions lead to inefficient scheduling and poor mission returns. Especially for UAVs, based on their agile and flexible ability, the scheduling result becomes diversiform; as affected by environment and unmanned aerial vehicle performance, different scheduling will lead to different time costs and mission payoffs. An effective scheduling solution is to arrange the UAVs reasonably to complete as many as missions possible with better quality and satisfaction of different demands. This paper proposes a method for mission decomposition or aggregation to generate a mission unit for specific UAVs based on the spatio-temporal constraints of different missions and UAV observation ability demands. In this way, the problems of lack or redundancy of resource scheduling, which can be caused by mission overload, various information demands and spatial overlapping will be effectively reduced. Furthermore, the global efficiency evaluation function is built by considering typical scheduling objectives, such as mission returns, priority and load balancing of resources. Then, an improved ant colony algorithm is designed to acquire an optimal scheduling scheme and the dynamic adjustment strategy is employed. Finally, the correctness and validity are demonstrated by the simulation experiment.

  12. Survey and evaluation of aging risk assessment methods and applications

    SciTech Connect

    Sanzo, D.L.; Kvam, P.; Apostolakis, G.; Wu, J.; Milici, T.; Ghoniem, N.; Guarro, S.

    1993-11-01

    The Nuclear Regulatory Commission (NRC) initiated the nuclear power plant aging research (NPAR) program about 6 years ago to gather information about nuclear power plant aging. Since then, this program has collected a significant amount of information, largely qualitative, on plant aging and its potential effects on plant safety. However, this body of knowledge has not yet been integrated into formalisms that can be used effectively and systematically to assess plant risk resulting from aging, although models for assessing the effect of increasing failure rates on core damage frequency have been proposed. The purpose of this review is to survey the work conducted to address the aging of systems, structures, and components (SSCs) of nuclear power plants (NPPs), as well as the associated data bases. The review takes a critical look at the need to revise probabilistic risk assessment (PRAs) so that they will include the contribution to risk from plant aging, the adequacy of existing methods for evaluating this contribution, and the adequacy of the data that have been used in these evaluation methods. A preliminary framework is identified for integrating the aging of SSCs into the PRA, including the identification of needed data for such an integration.

  13. Survey methods for assessing land cover map accuracy

    USGS Publications Warehouse

    Nusser, S.M.; Klaas, E.E.

    2003-01-01

    The increasing availability of digital photographic materials has fueled efforts by agencies and organizations to generate land cover maps for states, regions, and the United States as a whole. Regardless of the information sources and classification methods used, land cover maps are subject to numerous sources of error. In order to understand the quality of the information contained in these maps, it is desirable to generate statistically valid estimates of accuracy rates describing misclassification errors. We explored a full sample survey framework for creating accuracy assessment study designs that balance statistical and operational considerations in relation to study objectives for a regional assessment of GAP land cover maps. We focused not only on appropriate sample designs and estimation approaches, but on aspects of the data collection process, such as gaining cooperation of land owners and using pixel clusters as an observation unit. The approach was tested in a pilot study to assess the accuracy of Iowa GAP land cover maps. A stratified two-stage cluster sampling design addressed sample size requirements for land covers and the need for geographic spread while minimizing operational effort. Recruitment methods used for private land owners yielded high response rates, minimizing a source of nonresponse error. Collecting data for a 9-pixel cluster centered on the sampled pixel was simple to implement, and provided better information on rarer vegetation classes as well as substantial gains in precision relative to observing data at a single-pixel.

  14. A double-observer method to estimate detection rate during aerial waterfowl surveys

    USGS Publications Warehouse

    Koneff, M.D.; Royle, J. Andrew; Otto, M.C.; Wortham, J.S.; Bidwell, J.K.

    2008-01-01

    surveys where birds are distributed at low density in remote areas that are inaccessible by ground crews. Double-observer methods, however, estimate only detection rate of animals that are potentially observable given the survey method applied. Auxiliary data and methods must be considered to estimate overall detection rate.

  15. Comparison of the effects of filtration and preservation methods on analyses for strontium-90 in ground water

    USGS Publications Warehouse

    Knobel, L.L.; DeWayne, Cecil L.; Wegner, S.J.; Moore, L.L.

    1992-01-01

    From 1952 to 1988, about 140 curies of strontium-90 were discharged in liquid waste to disposal ponds and wells at the INEL (Idaho National Engineering Laboratory). Water from four wells was sampled as part of the U.S. Geological Survey's quality-assurance program to evaluate the effects of filtration and preservation methods on strontium-90 concentrations in ground water at the INEL. Water from each well was filtered through eithera 0.45- or a 0.1-micrometer membrane filter; unfiltered samples also were collected. Two sets of filtered and two sets of unfiltered water samples were collected at each well. One of the two sets of water samples was field acidified. Strontium-90 concentrations ranged from below the reporting level to 52 ?? 4 picocuries per liter. Descriptive statistics were used to determine reproducibility of the analytical results for strontium-90 concentrations in water from each well. Comparisons were made with unfiltered, acidified samples at each well. Analytical results for strontium-90 concentrations in water from well 88 were not in statistical agreement between the unfiltered, acidified sample and the filtered (0.45 micrometer), acidified sample. The strontium-90 concentration for water from well 88 was less than the reporting level. For water from wells with strontium-90 concentrations at or above the reporting level, 94 percent or more of the strontium-90 is in true solution or in colloidal particles smaller than 0.1 micrometer. These results suggest that changes in filtration and preservation methods used for sample collection do not significantly affect reproducibility of strontium-90 analyses in ground water at the INEL.

  16. A New Curb Detection Method for Unmanned Ground Vehicles Using 2D Sequential Laser Data

    PubMed Central

    Liu, Zhao; Wang, Jinling; Liu, Daxue

    2013-01-01

    Curb detection is an important research topic in environment perception, which is an essential part of unmanned ground vehicle (UGV) operations. In this paper, a new curb detection method using a 2D laser range finder in a semi-structured environment is presented. In the proposed method, firstly, a local Digital Elevation Map (DEM) is built using 2D sequential laser rangefinder data and vehicle state data in a dynamic environment and a probabilistic moving object deletion approach is proposed to cope with the effect of moving objects. Secondly, the curb candidate points are extracted based on the moving direction of the vehicle in the local DEM. Finally, the straight and curved curbs are detected by the Hough transform and the multi-model RANSAC algorithm, respectively. The proposed method can detect the curbs robustly in both static and typical dynamic environments. The proposed method has been verified in real vehicle experiments. PMID:23325170

  17. A new curb detection method for unmanned ground vehicles using 2D sequential laser data.

    PubMed

    Liu, Zhao; Wang, Jinling; Liu, Daxue

    2013-01-01

    Curb detection is an important research topic in environment perception, which is an essential part of unmanned ground vehicle (UGV) operations. In this paper, a new curb detection method using a 2D laser range finder in a semi-structured environment is presented. In the proposed method, firstly, a local Digital Elevation Map (DEM) is built using 2D sequential laser rangefinder data and vehicle state data in a dynamic environment and a probabilistic moving object deletion approach is proposed to cope with the effect of moving objects. Secondly, the curb candidate points are extracted based on the moving direction of the vehicle in the local DEM. Finally, the straight and curved curbs are detected by the Hough transform and the multi-model RANSAC algorithm, respectively. The proposed method can detect the curbs robustly in both static and typical dynamic environments. The proposed method has been verified in real vehicle experiments. PMID:23325170

  18. A Ground State Method for Continuum Systems Using Random Walks in the Space of Slater Determinants.^

    NASA Astrophysics Data System (ADS)

    Zhang, Shiwei; Krakauer, Henry

    2001-03-01

    We study a ground state quantum Monte Carlo method for electronic systems. The method is based on the constrained path Monte Carlo approach(S. Zhang, J. Carlson, and J. E. Gubernatis, Phys. Rev. B 55), 7464 (1997). developed for lattice models of correlated electrons. It works in second-quantized form and uses random walks involving full Slater determinants rather than individual real-space configurations. The method allows easy calculation of expectation values and also makes it straightforward to import standard techniques (e.g., pseudopotentials) used in density functional and quantum chemistry calculations. In general, Slater determinants will acquire overall complex phases, due to the Hubbard-Stratonovich transformation of the two-body potential. In order to control the sign decay, an approximation is developed for the propagation of complex Slater determinants by random walks. We test the method in a homogeneous 3-D electron gas (jellium) using a planewave basis. ^ Supported by NSF, ONR and Research Corporation.

  19. Revisions to some parameters used in stochastic-method simulations of ground motion

    USGS Publications Warehouse

    Boore, David; Thompson, Eric M.

    2015-01-01

    The stochastic method of ground‐motion simulation specifies the amplitude spectrum as a function of magnitude (M) and distance (R). The manner in which the amplitude spectrum varies with M and R depends on physical‐based parameters that are often constrained by recorded motions for a particular region (e.g., stress parameter, geometrical spreading, quality factor, and crustal amplifications), which we refer to as the seismological model. The remaining ingredient for the stochastic method is the ground‐motion duration. Although the duration obviously affects the character of the ground motion in the time domain, it also significantly affects the response of a single‐degree‐of‐freedom oscillator. Recently published updates to the stochastic method include a new generalized double‐corner‐frequency source model, a new finite‐fault correction, a new parameterization of duration, and a new duration model for active crustal regions. In this article, we augment these updates with a new crustal amplification model and a new duration model for stable continental regions. Random‐vibration theory (RVT) provides a computationally efficient method to compute the peak oscillator response directly from the ground‐motion amplitude spectrum and duration. Because the correction factor used to account for the nonstationarity of the ground motion depends on the ground‐motion amplitude spectrum and duration, we also present new RVT correction factors for both active and stable regions.

  20. A pose estimation method for unmanned ground vehicles in GPS denied environments

    NASA Astrophysics Data System (ADS)

    Tamjidi, Amirhossein; Ye, Cang

    2012-06-01

    This paper presents a pose estimation method based on the 1-Point RANSAC EKF (Extended Kalman Filter) framework. The method fuses the depth data from a LIDAR and the visual data from a monocular camera to estimate the pose of a Unmanned Ground Vehicle (UGV) in a GPS denied environment. Its estimation framework continuy updates the vehicle's 6D pose state and temporary estimates of the extracted visual features' 3D positions. In contrast to the conventional EKF-SLAM (Simultaneous Localization And Mapping) frameworks, the proposed method discards feature estimates from the extended state vector once they are no longer observed for several steps. As a result, the extended state vector always maintains a reasonable size that is suitable for online calculation. The fusion of laser and visual data is performed both in the feature initialization part of the EKF-SLAM process and in the motion prediction stage. A RANSAC pose calculation procedure is devised to produce pose estimate for the motion model. The proposed method has been successfully tested on the Ford campus's LIDAR-Vision dataset. The results are compared with the ground truth data of the dataset and the estimation error is ~1.9% of the path length.

  1. Simulations of Ground Motion in Southern California based upon the Spectral-Element Method

    NASA Astrophysics Data System (ADS)

    Tromp, J.; Komatitsch, D.; Liu, Q.

    2003-12-01

    We use the spectral-element method to simulate ground motion generated by recent well-recorded small earthquakes in Southern California. Simulations are performed using a new sedimentary basin model that is constrained by hundreds of petroleum industry well logs and more than twenty thousand kilometers of seismic reflection profiles. The numerical simulations account for 3D variations of seismic wave speeds and density, topography and bathymetry, and attenuation. Simulations for several small recent events demonstrate that the combination of a detailed sedimentary basin model and an accurate numerical technique facilitates the simulation of ground motion at periods of 2 seconds and longer inside the Los Angeles basin and 6 seconds and longer elsewhere. Peak ground displacement, velocity and acceleration maps illustrate that significant amplification occurs in the basin. Centroid-Moment Tensor mechanisms are obtained based upon Pnl and surface waveforms and numerically calculated 3D Frechet derivatives. We use a combination of waveform and waveform-envelope misfit criteria, and facilitate pure double-couple or zero-trace moment-tensor inversions.

  2. Computer program for simulation of variable recharge with the U. S. Geological Survey modular finite-difference ground-water flow model (MODFLOW)

    USGS Publications Warehouse

    Kontis, A.L.

    2001-01-01

    The Variable-Recharge Package is a computerized method designed for use with the U.S. Geological Survey three-dimensional finitedifference ground-water flow model (MODFLOW-88) to simulate areal recharge to an aquifer. It is suitable for simulations of aquifers in which the relation between ground-water levels and land surface can affect the amount and distribution of recharge. The method is based on the premise that recharge to an aquifer cannot occur where the water level is at or above land surface. Consequently, recharge will vary spatially in simulations in which the Variable- Recharge Package is applied, if the water levels are sufficiently high. The input data required by the program for each model cell that can potentially receive recharge includes the average land-surface elevation and a quantity termed ?water available for recharge,? which is equal to precipitation minus evapotranspiration. The Variable-Recharge Package also can be used to simulate recharge to a valley-fill aquifer in which the valley fill and the adjoining uplands are explicitly simulated. Valley-fill aquifers, which are the most common type of aquifer in the glaciated northeastern United States, receive much of their recharge from upland sources as channeled and(or) unchanneled surface runoff and as lateral ground-water flow. Surface runoff in the uplands is generated in the model when the applied water available for recharge is rejected because simulated water levels are at or above land surface. The surface runoff can be distributed to other parts of the model by (1) applying the amount of the surface runoff that flows to upland streams (channeled runoff) to explicitly simulated streams that flow onto the valley floor, and(or) (2) applying the amount that flows downslope toward the valley- fill aquifer (unchanneled runoff) to specified model cells, typically those near the valley wall. An example model of an idealized valley- fill aquifer is presented to demonstrate application of the

  3. Understanding Sample Surveys: Selective Learning about Social Science Research Methods

    ERIC Educational Resources Information Center

    Currin-Percival, Mary; Johnson, Martin

    2010-01-01

    We investigate differences in what students learn about survey methodology in a class on public opinion presented in two critically different ways: with the inclusion or exclusion of an original research project using a random-digit-dial telephone survey. Using a quasi-experimental design and data obtained from pretests and posttests in two public…

  4. Enhancing Field Research Methods with Mobile Survey Technology

    ERIC Educational Resources Information Center

    Glass, Michael R.

    2015-01-01

    This paper assesses the experience of undergraduate students using mobile devices and a commercial application, iSurvey, to conduct a neighborhood survey. Mobile devices offer benefits for enhancing student learning and engagement. This field exercise created the opportunity for classroom discussions on the practicalities of urban research, the…

  5. A Survey of Formal Methods for Intelligent Swarms

    NASA Technical Reports Server (NTRS)

    Truszkowski, Walt; Rash, James; Hinchey, Mike; Rouff, Chrustopher A.

    2004-01-01

    cutting edge in system correctness, and requires higher levels of assurance than other (traditional) missions that use a single or small number of spacecraft that are deterministic in nature and have near continuous communication access. One of the highest possible levels of assurance comes from the application of formal methods. Formal methods are mathematics-based tools and techniques for specifying and verifying (software and hardware) systems. They are particularly useful for specifying complex parallel systems, such as exemplified by the ANTS mission, where the entire system is difficult for a single person to fully understand, a problem that is multiplied with multiple developers. Once written, a formal specification can be used to prove properties of a system (e.g., the underlying system will go from one state to another or not into a specific state) and check for particular types of errors (e.g., race or livelock conditions). A formal specification can also be used as input to a model checker for further validation. This report gives the results of a survey of formal methods techniques for verification and validation of space missions that use swarm technology. Multiple formal methods were evaluated to determine their effectiveness in modeling and assuring the behavior of swarms of spacecraft using the ANTS mission as an example system. This report is the first result of the project to determine formal approaches that are promising for formally specifying swarm-based systems. From this survey, the most promising approaches were selected and are discussed relative to their possible application to the ANTS mission. Future work will include the application of an integrated approach, based on the selected approaches identified in this report, to the formal specification of the ANTS mission.

  6. New method for assessment of gait variability based on wearable ground reaction force sensor.

    PubMed

    Liu, Tao; Inoue, Yoshio; Shibata, Kyoko

    2008-01-01

    In this paper, a new quantitative method of analyzing gait variability using a developed wearable ground reaction force (GRF) sensor system is presented. The design of the sensor system is based on the use of five small 3-axial sensors distributed on the underside of a shoe, so that in human dynamics analysis this system can continuously measure vertical pressure force and bio-directional friction forces referring to anterior-posterior friction force and mediolateral friction force. Compared to existing spatio-temporal evaluation methods using traditional force plates or instrumented treadmills, the new method was developed based on measurements of ambulatory or wearable force sensor which can continuously measure ground reaction force in various environments not limited to the laboratory environment. The area of the center of pressure (CoP) distribution on the foot-plate and the average coefficient of variation of the 3-axial GRF, which correlate strongly with the distribution of CoP, are suggested parameters for quantifying gait variability. To certify the effectiveness of these parameters, we conducted an experimental study on a group of volunteer subjects who walked under a designed experimental protocol. PMID:19163171

  7. Efficient reconstruction method for ground layer adaptive optics with mixed natural and laser guide stars.

    PubMed

    Wagner, Roland; Helin, Tapio; Obereder, Andreas; Ramlau, Ronny

    2016-02-20

    The imaging quality of modern ground-based telescopes such as the planned European Extremely Large Telescope is affected by atmospheric turbulence. In consequence, they heavily depend on stable and high-performance adaptive optics (AO) systems. Using measurements of incoming light from guide stars, an AO system compensates for the effects of turbulence by adjusting so-called deformable mirror(s) (DMs) in real time. In this paper, we introduce a novel reconstruction method for ground layer adaptive optics. In the literature, a common approach to this problem is to use Bayesian inference in order to model the specific noise structure appearing due to spot elongation. This approach leads to large coupled systems with high computational effort. Recently, fast solvers of linear order, i.e., with computational complexity O(n), where n is the number of DM actuators, have emerged. However, the quality of such methods typically degrades in low flux conditions. Our key contribution is to achieve the high quality of the standard Bayesian approach while at the same time maintaining the linear order speed of the recent solvers. Our method is based on performing a separate preprocessing step before applying the cumulative reconstructor (CuReD). The efficiency and performance of the new reconstructor are demonstrated using the OCTOPUS, the official end-to-end simulation environment of the ESO for extremely large telescopes. For more specific simulations we also use the MOST toolbox. PMID:26906596

  8. A Method for Extracting Maximum Resolution Power Spectra from Galaxy Surveys

    NASA Astrophysics Data System (ADS)

    Tegmark, Max

    1995-12-01

    The power spectrum estimated from a galaxy redshift survey is the real spectrum convolved with a window function, so when estimating the power on very large scales (for small k), it is important that this window function be as narrow as possible. A method that achieves this is presented. The optimal fluctuation estimate is found to be the Fourier transform of the number density fluctuations n/nbar - 1 weighted by a function ψ0, and the optimal ψ0 is found to be the ground-state solution of the Schrödinger equation, with the inverse selection function as the potential. This quantum mechanics analogy occurs basically because we want the weight function to be narrow both in Fourier space (to give a narrow window) and in real space (to minimize the variance from shot noise). An optimal method for averaging the estimates at different k is also presented, generalizing the standard procedure of averaging over shells in k-space. Finally, a discrete version of the method is presented, dividing space into "fuzzy pixels," which has the advantage of being able to handle redshift distortions in a straightforward way.

  9. Topsoil thickness mapping at watershed scale by integration of field survey, geophysics and remote sensing methods

    NASA Astrophysics Data System (ADS)

    Francés, Alain Pascal; Lubczynski, Maciek

    2010-05-01

    The adequate parameterisation of near subsurface is a critical issue due to the large spatial variability of soil properties. Direct observations made by common invasive field sampling procedures through drilling and trench excavations can be complemented in an efficient way by non-invasive geophysical methods, improving spatial data coverage in cost and time efficient way. The geophysical methods measure a physical property of subsurface that is convertible into the parameter or variable of interest. Such conversion requires development of data integration method. In this study, we present a methodology of data integration to assess spatially the topsoil thickness at the watershed scale. To integrate the spatial variability of the soil characteristics, we used a combination of field survey, ground-geophysics, satellite and aerial imagery processing and statistical estimation techniques. The ground-geophysics was used to complement and extend the direct field observations of the topsoil thickness. The conversion of the geophysical data in topsoil thickness and the estimation of the topsoil thickness over the catchment were done through statistical methods that integrated auxiliary variables derived from the remote sensing imagery (soil and geomorphology classifications and terrain attributes). A simple and expedite soil classification based on multi-resolution segmentation of image objects and fuzzy logic was derived from a high-resolution multispectral QuickBird image combined with aerial photograph. Landform classes and terrain attributes were computed from the Global Digital Elevation Model (GDEM) of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite. We applied this methodology to the Pisões catchment (~19 km2, Portugal) where the AB horizon, following the standard pedologic classification, is characterized by its high concentration in swelling clay. In the first step, we elaborated the sampling schema of the geophysical

  10. A comparison of several surface finish measurement methods as applied to ground ceramic and metal surfaces

    SciTech Connect

    Blau, P.J.; Martin, R.L.; Riester, L.

    1996-01-01

    Surface finish is one of the most common measures of surface quality of ground ceramics and metal parts and a wide variety of methods and parameters have been developed to measure it. The purpose of this investigation was to compare the surface roughness parameters obtained on the same two specimens from three different types of measuring instruments: a traditional mechanical stylus system, a non-contact laser scanning system, and the atomic force microscope (two different AFM systems were compared). The same surface-ground silicon nitride and Inconel 625 alloy specimens were used for all measurements in this investigation. Significant differences in arithmetic average roughness, root-mean-square roughness, and peak-to-valley roughness were obtained when comparing data from the various topography measuring instruments. Non-contact methods agreed better with the others on the metal specimen than on the ceramic specimen. Reasons for these differences include the effective dimensions and geometry of the probe with respect to the surface topography; the reflectivity of the surface, and the type of filtering scheme Results of this investigation emphasize the importance of rigorously specifying the manner of surface roughness measurement when either reporting roughness data or when requesting that roughness data be provided.

  11. Ground truth methods for optical cross-section modeling of biological aerosols

    NASA Astrophysics Data System (ADS)

    Kalter, J.; Thrush, E.; Santarpia, J.; Chaudhry, Z.; Gilberry, J.; Brown, D. M.; Brown, A.; Carter, C. C.

    2011-05-01

    Light detection and ranging (LIDAR) systems have demonstrated some capability to meet the needs of a fastresponse standoff biological detection method for simulants in open air conditions. These systems are designed to exploit various cloud signatures, such as differential elastic backscatter, fluorescence, and depolarization in order to detect biological warfare agents (BWAs). However, because the release of BWAs in open air is forbidden, methods must be developed to predict candidate system performance against real agents. In support of such efforts, the Johns Hopkins University Applied Physics Lab (JHU/APL) has developed a modeling approach to predict the optical properties of agent materials from relatively simple, Biosafety Level 3-compatible bench top measurements. JHU/APL has fielded new ground truth instruments (in addition to standard particle sizers, such as the Aerodynamic particle sizer (APS) or GRIMM aerosol monitor (GRIMM)) to more thoroughly characterize the simulant aerosols released in recent field tests at Dugway Proving Ground (DPG). These instruments include the Scanning Mobility Particle Sizer (SMPS), the Ultraviolet Aerodynamic Particle Sizer (UVAPS), and the Aspect Aerosol Size and Shape Analyser (Aspect). The SMPS was employed as a means of measuring smallparticle concentrations for more accurate Mie scattering simulations; the UVAPS, which measures size-resolved fluorescence intensity, was employed as a path toward fluorescence cross section modeling; and the Aspect, which measures particle shape, was employed as a path towards depolarization modeling.

  12. A Deep Percolation Model for Estimating Ground-Water Recharge: Documentation of Modules for the Modular Modeling System of the U.S. Geological Survey

    USGS Publications Warehouse

    Vaccaro, J.J.

    2007-01-01

    A daily water-budget model for estimating ground-water recharge, the Deep Percolation Model, was modularized for inclusion into the U.S. Geological Survey's Modular Modeling System. The model was modularized in order to facilitate estimation of ground-water recharge under a large range in climatic, landscape, and land-use and land-cover conditions. The model can be applied to areas as large as regions or as small as a field plot. An overview of the Modular Modeling System and the Deep Percolation Model is presented. Data requirements, parameters, and variables for the model are described. The modules that compose the Deep Percolation Model are documented.

  13. Results of a Flight Simulation Software Methods Survey

    NASA Technical Reports Server (NTRS)

    Jackson, E. Bruce

    1995-01-01

    A ten-page questionnaire was mailed to members of the AIAA Flight Simulation Technical Committee in the spring of 1994. The survey inquired about various aspects of developing and maintaining flight simulation software, as well as a few questions dealing with characterization of each facility. As of this report, 19 completed surveys (out of 74 sent out) have been received. This paper summarizes those responses.

  14. Microtremor Array Measurement Survey and Strong Ground Motion Observation Activities of The MarDiM (SATREPS) Project

    NASA Astrophysics Data System (ADS)

    Ozgur Citak, Seckin; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Aksahin, Bengi; Arslan, Safa; Hatayama, Ken; Ohori, Michihiro; Hori, Muneo

    2015-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul and Tekirdag province at about 81 sites on October 2013 and September 2014. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A2) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor (CV-374A2) consist of three servo

  15. Ground penetrating radar survey on the cross-stratified overbank deposits from the 2006 eruption of Tungurahua volcano, Ecuador.

    NASA Astrophysics Data System (ADS)

    Amin Douillet, Guilhem; Abolghasem, Amir; Rémi Dujardin, Jean; Kueppers, Ulrich; Hall, Jonathan; Mothes, Patricia; Dingwell, Donald

    2013-04-01

    The deposits of the 2006 pyroclastic density currents (PDCs) at Tungurahua are organized as 1) massive, coarse-grained deposits confined to valleys of the drainage network and 2) cross-stratified, ash-dominated overbank deposits from dilute PDCs. These overbank deposits are exceptionally well preserved and show dune bedforms shaping the surface of the outcrops. In order to gain insights into the depositional mechanisms of the latter, we combined a terrestrial laser scanner (TLS) survey with a ground penetrating radar (GPR) dense network of profiles. The GPR survey permits to look at the internal cross stratification patterns in a non-destructive way. Three antennas with frequencies at 250, 500 and 800 MHz, respectively, permitted to image down to 10, 7 and 3 m depth. While the 800 MHz antenna was found to be very efficient to image cross-lamination, the 250 MHz antenna permitted to recognize major flow units. The GPR dataset profits from the TLS topography data, which are integrated in the processing of the data. From a dense array (profiles at 10 cm spacing) over different types of dune bedforms with the 800 MHz antenna, we manage to reconstruct the 3D internal patterns. Using the 250 MHz antenna, >50 profiles (20-80 m length) over a zone ca. 300*300 m permit to reconstruct and follow the major flow units on the overbanks and their 3D evolution as well as the pre-eruptive paleosoil. Notable results are: (1) the revelation of several units of dense pyroclastic flow deposits below the dilute PDC deposits on the overbanks. This may indicate that the valleys were filled by the time of deposition of the dune bedforms, a result not inferred in previous studies. Moreover, the number of units is greater than previously accessed. (2) For dune bedforms, the root of a structure is found to be located deeper than expected with striking spatial stability during the whole deposition stage, indicating that these bedforms are triggered by basal topographic disturbance. (3

  16. Analysis of subglacial hydrodynamics and ice dynamics through combined terrestrial laser scanning and ground penetrating radar survey

    NASA Astrophysics Data System (ADS)

    Gabbud, Chrystelle; Rüttimann, Sébastien; Micheletti, Natan; Irving, James; Lane, Stuart

    2015-04-01

    This study shows how high resolution surveys of subglacial channel morphology combined with high resolution terrestrial laser scanner survey of an Alpine glacier help to understand subglacial hydrological forcing of ice dynamics. The study area is the Haut Glacier d'Arolla in Switzerland, an Alpine valley glacier for which subglacial drainage system has been well studied. A new generation of terrestrial laser scanners was used to investigate glacier surface ablation and other elements of glacial hydrodynamics at exceptionally high spatial and temporal resolution. The LiDAR RIEGL VZ-6000 scanner, with a laser 3B specifically designed for measurements of snow and ice cover surfaces, was tested at seasonal and daily scales. The data revealed spatial variations in the patterns of surface melt, controlled by both aspect and differential debris cover at the seasonal scale, and controlled by ogive-related differences in ice surface debris content at the daily scale. More tentatively, intra-daily scale measurements pointed to possible hydraulic jacking of the glacier associated with short-term water pressure rises at the downstream part of the glacier. A ground-penetrating radar (GPR) field campaign was conducted a year later in the location where possible hydraulic jacking had been detected previously. The aims of this campaign were (i) to assess GPR usage for subglacial channel detection; (ii) identify more precisely the channel morphology; and (iii) investigate further the hydraulic jacking hypothesis. 100 MHz antennas were used to map a 240 x 34 m area near the glacier snout where the ice thickness did not exceed 50 m. The corresponding data, after processing, allowed reconstruction of the bed topography and the morphology of subglacial channels in 3D, showing two of the latter in this area. One channel was followed for approximately 20 m upglacier and corresponding morphology estimates were performed. These data allowed for 3D reconstructions of both the bed

  17. Microtremor Array Measurement Survey and Strong Ground Motion observation activities of The SATREPS, MarDiM project -Part 2-

    NASA Astrophysics Data System (ADS)

    Citak, Seckin; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Arslan, Safa; Aksahin, Bengi; Hatayama, Ken; Ohori, Michihiro; Hori, Muneo

    2016-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul, Tekirdag, Canakkale and Edirne provinces at about 109 sites on October 2013, September 2014 and 2015. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor (CV-374

  18. Remote sensing methods for power line corridor surveys

    NASA Astrophysics Data System (ADS)

    Matikainen, Leena; Lehtomäki, Matti; Ahokas, Eero; Hyyppä, Juha; Karjalainen, Mika; Jaakkola, Anttoni; Kukko, Antero; Heinonen, Tero

    2016-09-01

    To secure uninterrupted distribution of electricity, effective monitoring and maintenance of power lines are needed. This literature review article aims to give a wide overview of the possibilities provided by modern remote sensing sensors in power line corridor surveys and to discuss the potential and limitations of different approaches. Monitoring of both power line components and vegetation around them is included. Remotely sensed data sources discussed in the review include synthetic aperture radar (SAR) images, optical satellite and aerial images, thermal images, airborne laser scanner (ALS) data, land-based mobile mapping data, and unmanned aerial vehicle (UAV) data. The review shows that most previous studies have concentrated on the mapping and analysis of network components. In particular, automated extraction of power line conductors has achieved much attention, and promising results have been reported. For example, accuracy levels above 90% have been presented for the extraction of conductors from ALS data or aerial images. However, in many studies datasets have been small and numerical quality analyses have been omitted. Mapping of vegetation near power lines has been a less common research topic than mapping of the components, but several studies have also been carried out in this field, especially using optical aerial and satellite images. Based on the review we conclude that in future research more attention should be given to an integrated use of various data sources to benefit from the various techniques in an optimal way. Knowledge in related fields, such as vegetation monitoring from ALS, SAR and optical image data should be better exploited to develop useful monitoring approaches. Special attention should be given to rapidly developing remote sensing techniques such as UAVs and laser scanning from airborne and land-based platforms. To demonstrate and verify the capabilities of automated monitoring approaches, large tests in various environments

  19. Generalizing Observational Study Results: Applying Propensity Score Methods to Complex Surveys

    PubMed Central

    DuGoff, Eva H; Schuler, Megan; Stuart, Elizabeth A

    2014-01-01

    ObjectiveTo provide a tutorial for using propensity score methods with complex survey data. Data SourcesSimulated data and the 2008 Medical Expenditure Panel Survey. Study DesignUsing simulation, we compared the following methods for estimating the treatment effect: a naïve estimate (ignoring both survey weights and propensity scores), survey weighting, propensity score methods (nearest neighbor matching, weighting, and subclassification), and propensity score methods in combination with survey weighting. Methods are compared in terms of bias and 95 percent confidence interval coverage. In Example 2, we used these methods to estimate the effect on health care spending of having a generalist versus a specialist as a usual source of care. Principal FindingsIn general, combining a propensity score method and survey weighting is necessary to achieve unbiased treatment effect estimates that are generalizable to the original survey target population. ConclusionsPropensity score methods are an essential tool for addressing confounding in observational studies. Ignoring survey weights may lead to results that are not generalizable to the survey target population. This paper clarifies the appropriate inferences for different propensity score methods and suggests guidelines for selecting an appropriate propensity score method based on a researcher’s goal. PMID:23855598

  20. A wavelet-based baseline drift correction method for grounded electrical source airborne transient electromagnetic signals

    NASA Astrophysics Data System (ADS)

    Wang, Yuan 1Ji, Yanju 2Li, Suyi 13Lin, Jun 12Zhou, Fengdao 1Yang, Guihong

    2013-09-01

    A grounded electrical source airborne transient electromagnetic (GREATEM) system on an airship enjoys high depth of prospecting and spatial resolution, as well as outstanding detection efficiency and easy flight control. However, the movement and swing of the front-fixed receiving coil can cause severe baseline drift, leading to inferior resistivity image formation. Consequently, the reduction of baseline drift of GREATEM is of vital importance to inversion explanation. To correct the baseline drift, a traditional interpolation method estimates the baseline `envelope' using the linear interpolation between the calculated start and end points of all cycles, and obtains the corrected signal by subtracting the envelope from the original signal. However, the effectiveness and efficiency of the removal is found to be low. Considering the characteristics of the baseline drift in GREATEM data, this study proposes a wavelet-based method based on multi-resolution analysis. The optimal wavelet basis and decomposition levels are determined through the iterative comparison of trial and error. This application uses the sym8 wavelet with 10 decomposition levels, and obtains the approximation at level-10 as the baseline drift, then gets the corrected signal by removing the estimated baseline drift from the original signal. To examine the performance of our proposed method, we establish a dipping sheet model and calculate the theoretical response. Through simulations, we compare the signal-to-noise ratio, signal distortion, and processing speed of the wavelet-based method and those of the interpolation method. Simulation results show that the wavelet-based method outperforms the interpolation method. We also use field data to evaluate the methods, compare the depth section images of apparent resistivity using the original signal, the interpolation-corrected signal and the wavelet-corrected signal, respectively. The results confirm that our proposed wavelet-based method is an

  1. Quantifying greenhouse gas emissions from coal fires using airborne and ground-based methods

    USGS Publications Warehouse

    Engle, M.A.; Radke, L.F.; Heffern, E.L.; O'Keefe, J. M. K.; Smeltzer, C.D.; Hower, J.C.; Hower, J.M.; Prakash, A.; Kolker, A.; Eatwell, R.J.; ter, Schure A.; Queen, G.; Aggen, K.L.; Stracher, G.B.; Henke, K.R.; Olea, R.A.; Roman-Colon, Y.

    2011-01-01

    Coal fires occur in all coal-bearing regions of the world and number, conservatively, in the thousands. These fires emit a variety of compounds including greenhouse gases. However, the magnitude of the contribution of combustion gases from coal fires to the environment is highly uncertain, because adequate data and methods for assessing emissions are lacking. This study demonstrates the ability to estimate CO2 and CH4 emissions for the Welch Ranch coal fire, Powder River Basin, Wyoming, USA, using two independent methods: (a) heat flux calculated from aerial thermal infrared imaging (3.7-4.4td-1 of CO2 equivalent emissions) and (b) direct, ground-based measurements (7.3-9.5td-1 of CO2 equivalent emissions). Both approaches offer the potential for conducting inventories of coal fires to assess their gas emissions and to evaluate and prioritize fires for mitigation. ?? 2011.

  2. A double-observer method for reducing bias in faecal pellet surveys of forest ungulates

    USGS Publications Warehouse

    Jenkins, K.J.; Manly, B.F.J.

    2008-01-01

    1. Faecal surveys are used widely to study variations in abundance and distribution of forest-dwelling mammals when direct enumeration is not feasible. The utility of faecal indices of abundance is limited, however, by observational bias and variation in faecal disappearance rates that obscure their relationship to population size. We developed methods to reduce variability in faecal surveys and improve reliability of faecal indices. 2. We used double-observer transect sampling to estimate observational bias of faecal surveys of Roosevelt elk Cervus elaphus roosevelti and Columbian black-tailed deer Odocoileus hemionus columbianus in Olympic National Park, Washington, USA. We also modelled differences in counts of faecal groups obtained from paired cleared and uncleared transect segments as a means to adjust standing crop faecal counts for a standard accumulation interval and to reduce bias resulting from variable decay rates. 3. Estimated detection probabilities of faecal groups ranged from < 0.2-1.0 depending upon the observer, whether the faecal group was from elk or deer, faecal group size, distance of the faecal group from the sampling transect, ground vegetation cover, and the interaction between faecal group size and distance from the transect. 4. Models of plot-clearing effects indicated that standing crop counts of deer faecal groups required 34% reduction on flat terrain and 53% reduction on sloping terrain to represent faeces accumulated over a standard 100-day interval, whereas counts of elk faecal groups required 0% and 46% reductions on flat and sloping terrain, respectively. 5. Synthesis and applications. Double-observer transect sampling provides a cost-effective means of reducing observational bias and variation in faecal decay rates that obscure the interpretation of faecal indices of large mammal abundance. Given the variation we observed in observational bias of faecal surveys and persistence of faeces, we emphasize the need for future

  3. A greedy-based multiquadric method for LiDAR-derived ground data reduction

    NASA Astrophysics Data System (ADS)

    Chen, Chuanfa; Yan, Changqing; Cao, Xuewei; Guo, Jinyun; Dai, Honglei

    2015-04-01

    A new greedy-based multiquadric method (MQ-G) has been developed to perform LiDAR-derived ground data reduction by selecting a certain amount of significant terrain points from the raw dataset to keep the accuracy of the constructed DEMs as high as possible, while maximally retaining terrain features. In the process of MQ-G, the significant terrain points were selected with an iterative process. First, the points with the maximum and minimum elevations were selected as the initial significant points. Next, a smoothing MQ was employed to perform an interpolation with the selected critical points. Then, the importance of all candidate points was assessed by interpolation error (i.e. the absolute difference between the interpolated and actual elevations). Lastly, the most significant point in the current iteration was selected and used for point selection in the next iteration. The process was repeated until the number of selected points reached a pre-set level or no point was found to have the interpolation error exceeding a user-specified accuracy tolerance. In order to avoid the huge computing cost, a new technique was presented to quickly solve the systems of MQ equations in the global interpolation process, and then the global MQ was replaced with the local one when a certain amount of critical points were selected. Four study sites with different morphologies (i.e. flat, undulating, hilly and mountainous terrains) were respectively employed to comparatively analyze the performances of MQ-G and the classical data selection methods including maximum z-tolerance (Max-Z) and the random method for reducing LiDAR-derived ground datasets. Results show that irrespective of the number of selected critical points and terrain characteristics, MQ-G is always more accurate than the other methods for DEM construction. Moreover, MQ-G has a better ability of preserving terrain feature lines, especially for the undulating and hilly terrains.

  4. Evaluation of three methods for sampling ground-dwelling Ants in the Brazilian Cerrado.

    PubMed

    Lopes, Cauê T; Vasconcelos, Heraldo L

    2008-01-01

    Few studies have evaluated the efficiency of methods for sampling ants, especially in regions with highly variable vegetation physiognomies such as the Cerrado region of central Brazil. Here we compared three methods to collect ground-dwelling ants: pitfall traps, sardine baits, and the Winkler litter extractor. Our aim was to determine which method would be most appropriate to characterize the ant assemblages inhabiting different vegetation types. More species were collected with pitfall traps and with the Winkler extractor than with sardine baits. Pitfall traps collected more species in the cerrado (savanna) physiognomies, particularly in those with a poor litter cover, whereas the Winlker extractor was more efficient in the forest physiognomies, except the one subject to periodic inundations. There was a low similarity in species composition between forest and cerrado physiognomies, and this pattern was detected regardless of the method used to sampling ants. Therefore, even the use of a single, relatively selective method of collection can be enough for studies comparing highly distinct habitats and/or conditions. However, if the purpose of the sampling is to produce a more thoroughly inventory of the ant fauna, we suggest the use of a combination of methods, particularly pitfall traps and the Winkler extractor. Therefore, the Ants of the Leaf-Litter (ALL) Sampling Protocol appear to be an adequate protocol for sampling ants in the highly-threatened Brazilian cerrado biome. PMID:18813741

  5. Relative efficiency of four parameter-estimation methods in steady-state and transient ground-water flow models

    USGS Publications Warehouse

    Hill, M.C.

    1990-01-01

    Parameters in numerical ground-water flow models have been successfully estimated using nonlinear-optimization methods such as the modified Gauss-Newton (GN) method and conjugate-direction methods. This paper investigates the relative efficiency of GN and three conjugate-direction parameter-estimation methods on two-dimensional, steady-state and transient ground-water flow test cases. The steady-state test cases are included to compare the performance of the algorithm with published examples. The three conjugate-direction methods are the Fletcher-Reeves (FR) and quasi-Newton (QN) regression methods, and combination Fletcher-Reeves quasi-Newton (FR-QN). All three are combined with Newton's method of calculating step size. The numerical ground-water flow model is described by McDonald and Harbaugh.

  6. Comparison of annual accumulation rates derived from in situ and ground penetrating radar methods across Alaskan glaciers

    NASA Astrophysics Data System (ADS)

    McGrath, D.; Gusmeroli, A.; Oneel, S.; Sass, L. C.; Arendt, A. A.; Wolken, G. J.; Kienholz, C.; McNeil, C.

    2013-12-01

    Constraining annual snowfall accumulation in mountain glacier environments is essential for determining the annual mass balance of individual glaciers and predicting seasonal meltwater runoff to river and marine ecosystems. However, large spatial and elevation gradients, coupled with sparse point measurements preclude accurate quantification of this variable using traditional methods. Here, we report on an extensive field campaign conducted in March-May 2013 on key benchmark glaciers in Alaska, including Taku Glacier near Juneau, Scott Glacier near Cordova, both Eklutna and Wolverine Glacier near Anchorage and Gulkana Glacier in the interior Alaska Range. Over 50 km of 500 MHz common-offset ground penetrating radar (GPR) surveys were collected on each glacier, with an emphasis on capturing spatial variability in the accumulation zone. Frequent in situ observations were collected for comparison with the GPR, including probe depths, snow pits and shallow firn cores (~8 m). We report on spatial and elevation gradients across this suite of glaciers and across numerous climatic zones and discuss differences between GPR and in situ derived annual accumulation estimates. This comparison is an essential first step in order to effectively evaluate regional atmospheric re-analysis products.

  7. Electromagnetic survey of the K1070A burial ground at the Oak Ridge K-25 Site, Oak Ridge, Tennessee. Environmental Restoration Program

    SciTech Connect

    Nyquist, J.E.; Emery, M.S.

    1993-01-01

    The K1070A burial ground, located at the K-25 Site on the Oak Ridge Reservation, received chemical and radioactive wastes from the late 1940s until 1975. Analysis of water samples collected from nearby monitoring wells indicates that contamination is migrating offsite. In November 1991, Oak Ridge National Laboratory (ORNL) personnel collected high-resolution electrical terrain conductivity data at the K1070A burial ground. A Model EM31 terrain conductivity meter manufactured by Geonics Limited was used in conjunction with the ORNL-developed Ultrasonic Ranging and Data System (USRADS) to perform the survey. The purposeof the survey was to provide Environmental Restoration (ER) staff with a detailed map of the spatial variation of the apparent electrical conductivity of the shallow subsurface (upper 3 m) to assist them in siting future monitoring wells closer to the waste area without drilling into the buried waste.

  8. Simulation of cylindrical flow to a well using the U.S. Geological Survey Modular Finite-Difference Ground-Water Flow Model

    USGS Publications Warehouse

    Reilly, Thomas E.; Harbaugh, Arlen W.

    1993-01-01

    Cylindrical (axisymmetric) flow to a well is an important specialized topic of ground-water hydraulics and has been applied by many investigators to determine aquifer properties and determine heads and flows in the vicinity of the well. A recent modification to the U.S. Geological Survey Modular Three-Dimensional Finite-Difference Ground-Water Flow Model provides the opportunity to simulate axisymmetric flow to a well. The theory involves the conceptualization of a system of concentric shells that are capable of reproducing the large variations in gradient in the vicinity of the well by decreasing their area in the direction of the well. The computer program presented serves as a preprocessor to the U.S. Geological Survey model by creating the input data file needed to implement the axisymmetric conceptualization. Data input requirements to this preprocessor are described, and a comparison with a known analytical solution indicates that the model functions appropriately.

  9. Sensitivity of Spaceborne and Ground Radar Comparison Results to Data Analysis Methods and Constraints

    NASA Technical Reports Server (NTRS)

    Morris, Kenneth R.; Schwaller, Mathew

    2011-01-01

    With the availability of active weather radar observations from space from the Precipitation Radar (PR) on board the Tropical Rainfall Measuring Mission (TR.MM) satellite, numerous studies have been performed comparing PR reflectivity and derived rain rates to similar observations from ground-based weather radars (GR). These studies have used a variety of algorithms to compute matching PR and GR volumes for comparison. Most studies have used a fixed 3-dimensional Cartesian grid centered on the ground radar, onto which the PR and GR data are interpolated using a proprietary approach and/or commonly available GR analysis software (e.g., SPRINT, REORDER). Other studies have focused on the intersection of the PR and GR viewing geometries either explicitly or using a hybrid of the fixed grid and PR/GR common fields of view. For the Dual-Frequency Precipitation Radar (DPR) of the upcoming Global Precipitation Measurement (GPM) mission, a prototype DPR/GR comparison algorithm based on similar TRMM PR data has been developed that defines the common volumes in terms of the geometric intersection of PR and GR rays, where smoothing of the PR and GR data are minimized and no interpolation is performed. The PR and GR volume-averaged reflectivity values of each sample volume are accompanied by descriptive metadata, for attributes including the variability and maximum of the reflectivity within the sample volume, and the fraction of range gates in the sample average having reflectivity values above an adjustable detection threshold (typically taken to be 18 dBZ for the PR). Sample volumes are further characterized by rain type (Stratiform or Convective), proximity to the melting layer, underlying surface (land/water/mixed), and the time difference between the PR and GR observations. The mean reflectivity differences between the PR and GR can differ between data sets produced by the different analysis methods; and for the GPM prototype, by the type of constraints and

  10. Sightability adjustment methods for aerial surveys of wildlife populations

    USGS Publications Warehouse

    Steinhorst, R.K.; Samuel, M.D.

    1989-01-01

    Aerial surveys are routinely conducted to estimate the abundance of wildlife species and the rate of population change. However, sightability of animal groups is acknowledged as a significant source of bias in these estimates. Recent research has focused on the development of sightability models to predict the probability of sighting groups under various conditions. Given such models, we show how sightability can be incorporated into the estimator of population size as a probability of response using standard results from sample surveys. We develop formulas for the cases where the sighting probability must be estimated. An example, using data from a helicopter survey of moose in Alberta (Jacobson, Alberta Oil Sands Research Project Report, 1976), is given to illustrate the technique.

  11. Thermodynamic ground state of MgB{sub 6} predicted from first principles structure search methods

    SciTech Connect

    Wang, Hui; Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2 ; LeBlanc, K. A.; Gao, Bo; Yao, Yansun; Canadian Light Source, Saskatoon, Saskatchewan S7N 0X4

    2014-01-28

    Crystalline structures of magnesium hexaboride, MgB{sub 6}, were investigated using unbiased structure searching methods combined with first principles density functional calculations. An orthorhombic Cmcm structure was predicted as the thermodynamic ground state of MgB{sub 6}. The energy of the Cmcm structure is significantly lower than the theoretical MgB{sub 6} models previously considered based on a primitive cubic arrangement of boron octahedra. The Cmcm structure is stable against the decomposition to elemental magnesium and boron solids at atmospheric pressure and high pressures up to 18.3 GPa. A unique feature of the predicted Cmcm structure is that the boron atoms are clustered into two forms: localized B{sub 6} octahedra and extended B{sub ∞} ribbons. Within the boron ribbons, the electrons are delocalized and this leads to a metallic ground state with vanished electric dipoles. The present prediction is in contrast to the previous proposal that the crystalline MgB{sub 6} maintains a semiconducting state with permanent dipole moments. MgB{sub 6} is estimated to have much weaker electron-phonon coupling compared with that of MgB{sub 2}, and therefore it is not expected to be able to sustain superconductivity at high temperatures.

  12. Evaluation of ground motion scaling methods for analysis of structural systems

    USGS Publications Warehouse

    O'Donnell, A. P.; Beltsar, O.A.; Kurama, Y.C.; Kalkan, E.; Taflanidis, A.A.

    2011-01-01

    Ground motion selection and scaling comprises undoubtedly the most important component of any seismic risk assessment study that involves time-history analysis. Ironically, this is also the single parameter with the least guidance provided in current building codes, resulting in the use of mostly subjective choices in design. The relevant research to date has been primarily on single-degree-of-freedom systems, with only a few studies using multi-degree-of-freedom systems. Furthermore, the previous research is based solely on numerical simulations with no experimental data available for the validation of the results. By contrast, the research effort described in this paper focuses on an experimental evaluation of selected ground motion scaling methods based on small-scale shake-table experiments of re-configurable linearelastic and nonlinear multi-story building frame structure models. Ultimately, the experimental results will lead to the development of guidelines and procedures to achieve reliable demand estimates from nonlinear response history analysis in seismic design. In this paper, an overview of this research effort is discussed and preliminary results based on linear-elastic dynamic response are presented. ?? ASCE 2011.

  13. A validation of extraction methods for noninvasive sampling of glucocorticoids in free-living ground squirrels.

    PubMed

    Mateo, Jill M; Cavigelli, Sonia A

    2005-01-01

    Fecal hormone assays provide a powerful tool for noninvasive monitoring of endocrine status in wild animals. In this study we validated a protocol for extracting and measuring glucocorticoids in free-living and captive Belding's ground squirrels (Spermophilus beldingi). We first compared two commonly used extraction protocols to determine which performed better with commercially available antibodies. We next verified the preferred extraction method by correlating circulating and fecal glucocorticoid measures from a group of individuals over time. For this comparison, we used both a cortisol and a corticosterone antibody to determine which had greater affinity to the fecal metabolites. Cortisol was the primary circulating glucocorticoid, but both hormones were present in well above detectable concentrations in the blood, which does not occur in other sciurids. In addition, the cortisol antibody showed greater binding with the fecal extracts than did the corticosterone antibody. Finally, we used adrenocorticotropic hormone and dexamethasone challenges to demonstrate that changes in adrenal functioning are reflected in changing fecal corticoid levels. These results suggest that our extraction protocol provides a fast, reliable assay of stress hormones in free-living ground squirrels without the confounding influence of short-term rises in glucocorticoid concentrations caused by handling and restraint stress and that it can facilitate ecological and evolutionary studies of stress in wild species. PMID:16228945

  14. Gap interpolation by inpainting methods: Application to ground and space-based asteroseismic data

    NASA Astrophysics Data System (ADS)

    Pires, Sandrine; Mathur, Savita; García, Rafael A.; Ballot, Jérôme; Stello, Dennis; Sato, Kumiko

    2015-02-01

    In asteroseismology, the observed time series often suffers from incomplete time coverage due to gaps. The presence of periodic gaps may generate spurious peaks in the power spectrum that limit the analysis of the data. Various methods have been developed to deal with gaps in time series data. However, it is still important to improve these methods to be able to extract all the possible information contained in the data. In this paper, we propose a new approach to handling the problem, the so-called inpainting method. This technique, based on a prior condition of sparsity, enables the gaps in the data to be judiciously fill-in thereby preserving the asteroseismic signal as far as possible. The impact of the observational window function is reduced and the interpretation of the power spectrum simplified. This method is applied on both ground- and space-based data. It appears that the inpainting technique improves the detection and estimation of the oscillation modes. Additionally, it can be used to study very long time series of many stars because it is very fast to compute. For a time series of 50 days of CoRoT-like data, it allows a speed-up factor of 1000, if compared to methods with the same accuracy.

  15. Using a fast Fourier method to model sound propagation in a stratified atmosphere over a stratified porous-elastic ground

    NASA Technical Reports Server (NTRS)

    Tooms, S.; Attenborough, K.

    1990-01-01

    Using a Fast Fourier integration method and a global matrix method for solution of the boundary condition equations at all interfaces simultaneously, a useful tool for predicting acoustic propagation in a stratified fluid over a stratified porous-elastic solid was developed. The model for the solid is a modified Biot-Stoll model incorporating four parameters describing the pore structure corresponding to the Rayleigh-Attenborough rigid-porous structure model. The method is also compared to another Fast Fourier code (CERL-FFP) which models the ground as an impedance surface under a horizontally stratified air. Agreement with the CERL FFP is good. The effects on sound propagation of a combination of ground elasticity, complex ground structure, and atmospheric conditions are demonstrated by theoretical results over a snow layer, and experimental results over a model ground surface.

  16. Typical geologic disaster surveying in Wenchuan 8.0 earthquake zone using high resolution ground LiDAR and UAV remote sensing

    NASA Astrophysics Data System (ADS)

    Jiang, Hongbo; Su, Yuanyuan; Jiao, Qisong; Zhang, Jingfa; Lixia, Gong; Luo, Yi

    2014-11-01

    There are nearly all kinds of typical earthquake types in Wenchuan earthquake relics. For the protection and efficient use of seismic data of relics, ground Lidar and UAV are used collected data about the ruined buildings, seismic scarps and other typical seismic information in Wenchuan, Beichuan, Bailu Middle School , Dujiangyan and Xiaoyudong earthquake relics. These data are processed and a high-precision surveying flow of typical earthquake relics is preliminarily formed.

  17. Understanding long-term baseflow water quality trends using a synoptic survey of the ground water-surface water interface, central Wisconsin.

    PubMed

    Browne, Bryant A; Guldan, Nathan M

    2005-01-01

    The relationship between stream water quality and landscape activities is difficult to evaluate where the principal source of stream flow is ground water seepage because the average travel time from ground water recharge areas to stream discharge positions can be on the order of decades. We tested the idea that past and future baseflow water quality can be predicted based on a synoptic survey of ground water recharge age-dates (based on chlorofluorocarbon [CFC] measurements) and water quality measurements obtained at the ground water-surface water interface. In this study we (i) characterize the discharge-weighted age distribution and water quality of ground water seepage into the Little Plover River (LPR); (ii) use this information to backcast and forecast baseflow NO(3)(-) concentrations; and (iii) evaluate NO(3)(-) backcasts against historical baseflow data (1960 to 2000). The discharge-weighted apparent CFC age of ground water seepage into the LPR was 23.7 (+/-7) yr. Baseflow backcasts matched the four decade rise of baseflow NO(3)(-) from 2 to 8 mg L(-1). Baseflow forecasts included three scenarios. Scenario A projects the historical rise of NO(3)(-) in the LPR basin's ground water recharge through 2050. Scenario B projects a leveling off of NO(3)(-) in ground water recharge in the year 2000. Scenario C projects a leveling off in the year 1985. Under Scenario A, LPR baseflow NO(3)(-) will increase steadily from 8 to 19 mg L(-1) between 2000 and 2050. Under scenarios B and C baseflow NO(3)(-) will plateau at 13 mg L(-1) in 2030 and at 10 mg L(-1) in 2010, respectively. The approach developed in this study can be used to (i) reconstruct historical baseflow water quality patterns in the absence of long-term monitoring data and (ii) project the effects of potential management decision on future water quality. PMID:15843645

  18. Methods Used to Assess the Susceptibility to Contamination of Transient, Non-Community Public Ground-Water Supplies in Indiana

    USGS Publications Warehouse

    Arihood, Leslie D.; Cohen, David A.

    2006-01-01

    The Safe Water Drinking Act of 1974 as amended in 1996 gave each State the responsibility of developing a Source-Water Assessment Plan (SWAP) that is designed to protect public-water supplies from contamination. Each SWAP must include three elements: (1) a delineation of the source-water protection area, (2) an inventory of potential sources of contaminants within the area, and (3) a determination of the susceptibility of the public-water supply to contamination from the inventoried sources. The Indiana Department of Environmental Management (IDEM) was responsible for preparing a SWAP for all public-water supplies in Indiana, including about 2,400 small public ground-water supplies that are designated transient, non-community (TNC) supplies. In cooperation with IDEM, the U.S. Geological Survey compiled information on conditions near the TNC supplies and helped IDEM complete source-water assessments for each TNC supply. The delineation of a source-water protection area (called the assessment area) for each TNC ground-water supply was defined by IDEM as a circular area enclosed by a 300-foot radius centered at the TNC supply well. Contaminants of concern (COCs) were defined by IDEM as any of the 90 contaminants for which the U.S. Environmental Protection Agency has established primary drinking-water standards. Two of these, nitrate as nitrogen and total coliform bacteria, are Indiana State-regulated contaminants for TNC water supplies. IDEM representatives identified potential point and nonpoint sources of COCs within the assessment area, and computer database retrievals were used to identify potential point sources of COCs in the area outside the assessment area. Two types of methods-subjective and subjective hybrid-were used in the SWAP to determine susceptibility to contamination. Subjective methods involve decisions based upon professional judgment, prior experience, and (or) the application of a fundamental understanding of processes without the collection and

  19. Cross Cultural Methods for Survey Research in Black Urban Areas.

    ERIC Educational Resources Information Center

    Word, Carl O.

    This paper summarizes the development of a new approach to survey research in black urban communities, in part by adapting standard techniques. Attention is directed at a group of salient assumptions underlying social science investigations, namely: (1) the universality of majority culture models of attitude structure; (2) sociolinguistic and…

  20. A Socratic Method for Surveying Students' Readiness to Study Evolution

    ERIC Educational Resources Information Center

    Stansfield, William D.

    2013-01-01

    Before beginning a series of presentations on evolution, it would be prudent to survey the general level of students' understanding of prerequisite basic concepts of reproduction, heredity, ontology, and phenotypic diversity so that teachers can avoid devoting time to well-known subjects of general knowledge and can spend more time on subjects…

  1. Standardised survey method for identifying catchment risks to water quality.

    PubMed

    Baker, D L; Ferguson, C M; Chier, P; Warnecke, M; Watkinson, A

    2016-06-01

    This paper describes the development and application of a systematic methodology to identify and quantify risks in drinking water and recreational catchments. The methodology assesses microbial and chemical contaminants from both diffuse and point sources within a catchment using Escherichia coli, protozoan pathogens and chemicals (including fuel and pesticides) as index contaminants. Hazard source information is gathered by a defined sanitary survey process involving use of a software tool which groups hazards into six types: sewage infrastructure, on-site sewage systems, industrial, stormwater, agriculture and recreational sites. The survey estimates the likelihood of the site affecting catchment water quality, and the potential consequences, enabling the calculation of risk for individual sites. These risks are integrated to calculate a cumulative risk for each sub-catchment and the whole catchment. The cumulative risks process accounts for the proportion of potential input sources surveyed and for transfer of contaminants from upstream to downstream sub-catchments. The output risk matrices show the relative risk sources for each of the index contaminants, highlighting those with the greatest impact on water quality at a sub-catchment and catchment level. Verification of the sanitary survey assessments and prioritisation is achieved by comparison with water quality data and microbial source tracking. PMID:27280603

  2. Methods for Using Ground-Water Model Predictions to Guide Hydrogeologic Data Collection, with Applications to the Death Valley Regional Ground-Water Flow System

    SciTech Connect

    Claire R. Tiedeman; M.C. Hill; F.A. D'Agnese; C.C. Faunt

    2001-07-31

    Calibrated models of ground-water systems can provide substantial information for guiding data collection. This work considers using such models to guide hydrogeologic data collection for improving model predictions, by identifying model parameters that are most important to the predictions. Identification of these important parameters can help guide collection of field data about parameter values and associated flow-system features that can lead to improved predictions. Methods for identifying parameters important to predictions include prediction scaled sensitivities (PSS), which account for uncertainty on individual parameters as well as prediction sensitivity to parameters, and a new ''value of improved information'' (VOII) method, which includes the effects of parameter correlation in addition to individual parameter uncertainty and prediction sensitivity. The PSS and VOII methods are demonstrated using a model of the Death Valley regional ground-water flow system. The predictions of interest are advective-transport paths originating at sites of past underground nuclear testing. Results show that for two paths evaluated, the most important parameters include a subset of five or six of the 23 defined model parameters. Some of the parameters identified as most important are associated with flow-system attributes that do not lie in the immediate vicinity of the paths. Results also indicate that the PSS and VOII methods can identify different important parameters. Because the methods emphasize somewhat different criteria for parameter importance, it is suggested that parameters identified by both methods be carefully considered in subsequent data collection efforts aimed at improving model predictions.

  3. Prediction of Ground Vibration from Trains Using Seismic Reflectivity Methods for a Porous Soil

    NASA Astrophysics Data System (ADS)

    NELSON, J. T.

    2000-03-01

    Biot's model of wave propagation in porous isotropic materials is explored for predicting ground vibration from rail vehicles on vertically heterogeneous isotropic saturated soil and rock using seismic reflectivity methods combined with a multi-degree-of-freedom model of a transit vehicle bogie. A sketch of the mathematical theory, canonical results for step loads on a porous half-space, spectral responses for simple layer profiles, and an example of a prediction for rail transit vehicles are presented. The model indicates that saturation of the soil introduces excess attenuation in the vibration response of the soil, and that both pitch and roll moments in addition to vertical forces caused by the vehicle bogie may be significant sources of vibration.

  4. Ground-penetrating radar methods used in surface-water discharge measurements

    USGS Publications Warehouse

    Haeni, F.P.; Buursink, Marc L.; Costa, John E.; Melcher, Nick B.; Cheng, Ralph T.; Plant, William J.

    2000-01-01

    In 1999, an experiment was conducted to see if a combination of complementary radar methods could be used to calculate the discharge of a river without having any of the measuring equipment in the water. The cross-sectional area of the 183-meter wide Skagit River in Washington State was measured using a ground-penetrating radar (GPR) system with a single 100-MHz antenna. A van-mounted, side-looking pulsed-Doppler radar system was used to collect water-surface velocity data across the same section of the river. The combined radar data sets were used to calculate the river discharge and the results compared closely to the discharge measurement made by using the standard in-water measurement techniques.

  5. Path durations for use in the stochastic‐method simulation of ground motions

    USGS Publications Warehouse

    Boore, David M.; Thompson, Eric M.

    2014-01-01

    The stochastic method of ground‐motion simulation assumes that the energy in a target spectrum is spread over a duration DT. DT is generally decomposed into the duration due to source effects (DS) and to path effects (DP). For the most commonly used source, seismological theory directly relates DS to the source corner frequency, accounting for the magnitude scaling of DT. In contrast, DP is related to propagation effects that are more difficult to represent by analytic equations based on the physics of the process. We are primarily motivated to revisit DT because the function currently employed by many implementations of the stochastic method for active tectonic regions underpredicts observed durations, leading to an overprediction of ground motions for a given target spectrum. Further, there is some inconsistency in the literature regarding which empirical duration corresponds to DT. Thus, we begin by clarifying the relationship between empirical durations and DT as used in the first author’s implementation of the stochastic method, and then we develop a new DP relationship. The new DP function gives significantly longer durations than in the previous DP function, but the relative contribution of DP to DT still diminishes with increasing magnitude. Thus, this correction is more important for small events or subfaults of larger events modeled with the stochastic finite‐fault method.

  6. A new method to obtain uniform distribution of ground control points based on regional statistical information

    NASA Astrophysics Data System (ADS)

    Ma, Chao; An, Wei; Deng, Xinpu

    2015-10-01

    The Ground Control Points (GCPs) is an important source of fundamental data in geometric correction for remote sensing imagery. The quantity, accuracy and distribution of GCPs are three factors which may affect the accuracy of geometric correction. It is generally required that the distribution of GCP should be uniform, so they can fully control the accuracy of mapping regions. In this paper, we establish an objective standard of evaluating the uniformity of the GCPs' distribution based on regional statistical information (RSI), and get an optimal distribution of GCPs. This sampling method is called RSIS for short in this work. The Amounts of GCPs in different regions by equally partitioning the image in regions in different manners are counted which forms a vector called RSI vector in this work. The uniformity of GCPs' distribution can be evaluated by a mathematical quantity of the RSI vector. An optimal distribution of GCPs is obtained by searching the RSI vector with the minimum mathematical quantity. In this paper, the simulation annealing is employed to search the optimal distribution of GCPs that have the minimum mathematical quantity of the RSI vector. Experiments are carried out to test the method proposed in this paper, and sampling designs compared are simple random sampling and universal kriging model-based sampling. The experiments indicate that this method is highly recommended as new GCPs sampling design method for geometric correction of remotely sensed imagery.

  7. Collaborative study of an enzymatic digestion method for the isolation of light filth from ground beef or hamburger.

    PubMed

    Alioto, P; Andreas, M

    1976-01-01

    Collaborative results are presented for a proposed method for light filth extraction from ground beef or hamburger. The method involves enzymatic digestion, wet sieving, and extraction with light mineral oil from 40% isopropanol. Recoveries are good and filter papers are clean. This method has been adopted as official first action. PMID:765321

  8. Methods of the International Tobacco Control (ITC) China Survey: Waves 1, 2, and 3

    PubMed Central

    Wu, Changbao; Thompson, Mary E.; Fong, Geoffrey T.; Jiang, Yuan; Yang, Yan; Feng, Guoze; Quah, Anne C.K.

    2015-01-01

    This paper describes the methods of sampling design and data collection of Waves 1, 2, and 3 of the ITC China Survey, with major focus on longitudinal features of the study. Key measures of quality of the survey data, such as retention rates and final sample sizes, are presented. Sample replenishment procedures are outlined, including the addition of a new city, Kunming, at Wave 3. Methods for constructing the longitudinal and cross-sectional survey weights are briefly described. PMID:25550421

  9. Ground-water contamination by crude oil at the Bemidji, Minnesota, research site; US Geological Survey Toxic Waste--ground-water contamination study

    USGS Publications Warehouse

    1984-01-01

    The project site is near Bemidji in northern Minnesota where an accidental spill of 10,500 barrels of crude oil occurred when a pipeline broke on August 20, 1979. Regulatory and remedial actions have been completed. The site is in a remote area with neither man-made hydraulic stresses nor other anthropogenic sources of the compounds of interest. The spill is in the recharge area of a local flow system that discharges to a small closed lake approximately 1,000 feet down the hydraulic gradient. The aquifer is pitted outwash dissected by younger glacial channels and is underlain by poorly permeable till at a depth of about 80 feet. Ground water dissolves oil floating on the water table under the spill site and moves toward the lake. At the water table, ground water enters the lake through lacustrine sediments; at depth, flow may be underneath the lake through the outwash. Contaminant transport has been as rapid as 4 feet per day based on the rate of movement of contaminants monitored through wells installed within a few days of the spill, but average rates are undoubtedly much less.

  10. Effects of land use on ground-water quality in central Florida - Preliminary results: U. S. Geological Survey Toxic Waste - Ground-Water Contamination Program

    SciTech Connect

    Rutledge, A.T.

    1987-01-01

    Activities of man in areas of recharge to the Floridian aquifer system that may be affecting groundwater quality include: (1) the use of drainage wells for stormwater disposal in urban areas, (2) the use of pesticides and fertilizers in citrus groves, and (3) the mining and processing of phosphate ore in mining areas. Preliminary findings about the impact of these land uses on groundwater quality are presented. Drainage wells convey excess urban stormwater directly to the Upper Floridian aquifer. The volatile organic compounds are the most common contaminants in ground water. Trace elements such as chromium and lead are entering the aquifer but their movement is apparently attenuated by precipitation reactions associated with high pH or by cation-exchange reactions. Among the trace elements and organic chemicals, most ground-water contamination in citrus production areas is caused by pesticide; other contaminants include benzene, toluene, naphthalene, and indene compounds. In the phosphate mining area, constituents of concern are arsenic, selenium, and mercury, and secondarily lead, chromium, cadmium, and others. Organic compounds such as fluorene, naphthalene, di-n-butyl phthalate, alkylated benzenes and naphthalenes, and indene compounds also are entering groundwater. 29 refs., 13 figs., 16 tabs.

  11. A Survey of Functional Behavior Assessment Methods Used by Behavior Analysts in Practice

    ERIC Educational Resources Information Center

    Oliver, Anthony C.; Pratt, Leigh A.; Normand, Matthew P.

    2015-01-01

    To gather information about the functional behavior assessment (FBA) methods behavior analysts use in practice, we sent a web-based survey to 12,431 behavior analysts certified by the Behavior Analyst Certification Board. Ultimately, 724 surveys were returned, with the results suggesting that most respondents regularly use FBA methods, especially…

  12. Consulting the Delphi: A New Idea for Collecting Student Feedback through the Two Survey Method (TSM)

    ERIC Educational Resources Information Center

    Finelli, Cynthia J.; Wright, Mary C.; Pinder-Grover, Tershia

    2010-01-01

    The Two Survey Method (TSM) is a new time-efficient tool for gathering formative student feedback. Based on the Delphi technique, the TSM uses iterative surveys to develop student consensus about key strengths and suggestions for instruction. Evaluation data indicate that both faculty and students are satisfied with the method's efficiency and the…

  13. Survey of Machine Learning Methods for Database Security

    NASA Astrophysics Data System (ADS)

    Kamra, Ashish; Ber, Elisa

    Application of machine learning techniques to database security is an emerging area of research. In this chapter, we present a survey of various approaches that use machine learning/data mining techniques to enhance the traditional security mechanisms of databases. There are two key database security areas in which these techniques have found applications, namely, detection of SQL Injection attacks and anomaly detection for defending against insider threats. Apart from the research prototypes and tools, various third-party commercial products are also available that provide database activity monitoring solutions by profiling database users and applications. We present a survey of such products. We end the chapter with a primer on mechanisms for responding to database anomalies.

  14. Detection of conduit-controlled ground-water flow in northwestern Puerto Rico using aerial photograph interpretation and geophysical methods

    USGS Publications Warehouse

    Rodríguez-Martínez, Jesús; Richards, Ronald T.

    2000-01-01

    The development potential of ground-water resources in the karst limestone of northwestern Puerto Rico, in an area extending from the Río Camuy to Aguadilla, is uncertain as a result of limited knowledge of the location of areas where a high density of cavities (interconnected fractures, conduits, and other dissolution features) might suggest the occurrence of high water yields. The presence in northwestern Puerto Rico of numerous coastal submarine springs, cavernous porosity in some of the wells, and rivers with entrenched and underground paths, indicate that it is probable that water-bearing, subterranean interconnected cavities occur in the area between the Río Camuy and Aguadilla. The number of exploratory wells needed to determine the location of these conduits or zones of enhanced secondary porosity could be substantially reduced if more information were available about the location of these subterranean features, greatly reducing the drilling costs associated with a trial-and-error exploratory process. A 3-year study was conducted by the U.S. Geological Survey, in cooperation with the Puerto Rico Aqueduct and Sewer Authority, to detect the presence of cavities that might suggest the occurrence of conduit-controlled groundwater flow. Aerial photographs, geologic and topographic maps, and field reconnaissance were used to identify such linear terrain features as ridges, entrenched canyons, and fracture traces. Natural potential and gravity geophysical methods were also used. The following sites were selected for the aerial photograph interpretation and geophysical testing: Caimital Bajo uplands and former Ramey Air Force Base in Aguadilla; Quebrada de los Cedros between Aguadilla and Isabela; the University of Puerto Rico Agricultural Experiment Station, Otilio dairy farm, and Pozo Brujo in Isabela; the Monte Encantado area in Moca and Isabela; and the Rio Camuy cave system in Hatillo and Camuy. In general, the degree of success varied with site and the

  15. AIS-2 radiometry and a comparison of methods for the recovery of ground reflectance

    NASA Technical Reports Server (NTRS)

    Conel, James E.; Green, Robert O.; Vane, Gregg; Bruegge, Carol J.; Alley, Ronald E.; Curtiss, Brian J.

    1987-01-01

    A field experiment and its results involving Airborne Imaging Spectrometer-2 data are described. The radiometry and spectral calibration of the instrument are critically examined in light of laboratory and field measurements. Three methods of compensating for the atmosphere in the search for ground reflectance are compared. It was found that laboratory determined responsitivities are 30 to 50 percent less than expected for conditions of the flight for both short and long wavelength observations. The combined system atmosphere surface signal to noise ratio, as indexed by the mean response divided by the standard deviation for selected areas, lies between 40 and 110, depending upon how scene averages are taken, and is 30 percent less for flight conditions than for laboratory. Atmospheric and surface variations may contribute to this difference. It is not possible to isolate instrument performance from the present data. As for methods of data reduction, the so-called scene average or log-residual method fails to recover any feature present in the surface reflectance, probably because of the extreme homogeneity of the scene.

  16. Proposed expansion of the City of Albuquerque/U.S. Geological Survey ground-water-level monitoring network for the middle Rio Grande Basin, New Mexico

    USGS Publications Warehouse

    Bexfield, L.M.

    1998-01-01

    The Middle Rio Grande Basin in central New Mexico, extending from Cochiti Lake on the north to San Acacia on the south, covers an area of about 3,060 square miles. Ground-water withdrawals in the basin are concentrated in and around the city of Albuquerque. Because of rapid increases in population and associated ground-water pumpage, a network of wells was established cooperatively by the City of and the U.S. Geological Survey between April 1982 and September 1983 to monitor changes in ground-water levels throughout the basin. Expansion of this network has been identified as an essential element in plans to study the relation between surface water and ground water in the basin. An inventory of existing wells in the Albuquerque metropolitan area has brought together information on about 400 wells that either are being monitored for water levels or would be good candidates for monitoring. About 115 wells or well sites are proposed as additions to the current 128-well ground-water-level monitoring network for the Middle Rio Grande Basin. Despite the extensive network that would be created by the addition of the proposed existing wells, however, certain parts of the Albuquerque metropolitan area would remain without adequate coverage areally and/or with depth in the Santa Fe Group aquifer until the installation of the proposed new monitoring wells.

  17. Reaching the ground state of a quantum spin glass using a zero-temperature quantum Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Das, Arnab; Chakrabarti, Bikas K.

    2008-12-01

    Here we discuss the annealing behavior of an infinite-range ±J Ising spin glass in the presence of a transverse field using a zero-temperature quantum Monte Carlo method. Within the simulation scheme, we demonstrate that quantum annealing not only helps finding the ground state of a classical spin glass, but can also help simulating the ground state of a quantum spin glass, in particular, when the transverse field is low, much more efficiently.

  18. Reaching the ground state of a quantum spin glass using a zero-temperature quantum Monte Carlo method.

    PubMed

    Das, Arnab; Chakrabarti, Bikas K

    2008-12-01

    Here we discuss the annealing behavior of an infinite-range +/-J Ising spin glass in the presence of a transverse field using a zero-temperature quantum Monte Carlo method. Within the simulation scheme, we demonstrate that quantum annealing not only helps finding the ground state of a classical spin glass, but can also help simulating the ground state of a quantum spin glass, in particular, when the transverse field is low, much more efficiently. PMID:19256816

  19. Survey of Technetium Analytical Production Methods Supporting Hanford Nuclear Materials Processing

    SciTech Connect

    TROYER, G.L.

    1999-11-03

    This document provides a historical survey of analytical methods used for measuring {sup 99}Tc in nuclear fuel reprocessing materials and wastes at Hanford. Method challenges including special sludge matrices tested are discussed. Special problems and recommendations are presented.

  20. Concordance and discordance of sequence survey methods for molecular epidemiology

    PubMed Central

    Hasan, Nur A.; Cebula, Thomas A.; Colwell, Rita R.; Robison, Richard A.; Johnson, W. Evan; Crandall, Keith A.

    2015-01-01

    The post-genomic era is characterized by the direct acquisition and analysis of genomic data with many applications, including the enhancement of the understanding of microbial epidemiology and pathology. However, there are a number of molecular approaches to survey pathogen diversity, and the impact of these different approaches on parameter estimation and inference are not entirely clear. We sequenced whole genomes of bacterial pathogens, Burkholderia pseudomallei, Yersinia pestis, and Brucella spp. (60 new genomes), and combined them with 55 genomes from GenBank to address how different molecular survey approaches (whole genomes, SNPs, and MLST) impact downstream inferences on molecular evolutionary parameters, evolutionary relationships, and trait character associations. We selected isolates for sequencing to represent temporal, geographic origin, and host range variability. We found that substitution rate estimates vary widely among approaches, and that SNP and genomic datasets yielded different but strongly supported phylogenies. MLST yielded poorly supported phylogenies, especially in our low diversity dataset, i.e., Y. pestis. Trait associations showed that B. pseudomallei and Y. pestis phylogenies are significantly associated with geography, irrespective of the molecular survey approach used, while Brucella spp. phylogeny appears to be strongly associated with geography and host origin. We contrast inferences made among monomorphic (clonal) and non-monomorphic bacteria, and between intra- and inter-specific datasets. We also discuss our results in light of underlying assumptions of different approaches. PMID:25737810

  1. GLACIER MONITORING SYSTEM IN COLOMBIA - complementing glaciological measurements with laser-scanning and ground-penetrating radar surveys

    NASA Astrophysics Data System (ADS)

    Ceballos, Jorge; Micheletti, Natan; Rabatel, Antoine; Mölg, Nico; Zemp, Michael

    2015-04-01

    Colombia (South America) has six small glaciers (total glacierized area of 45 Km2); their geographical location, close to zero latitude, makes them very sensitive to climate changes. An extensive monitoring program is being performed since 2006 on two glaciers, with international cooperation supports. This presentation summarizes the results of glacier changes in Colombia and includes the latest results obtained within the CATCOS Project - Phase 1 (Capacity Building and Twinning for Climate Observing Systems) signed between Colombia and Switzerland, and within the Joint Mixte Laboratory GREAT-ICE (IRD - France), with the application of LiDAR technology and GPR-based ice thickness measurements at Conejeras Glacier. Conejeras Glacier (Lat. N. 4° 48' 56"; Long. W. 75° 22' 22"; Alt. Max. 4915m.; Alt. Min. 4730m. Area 0.2 Km2) is located on the north-western side of Santa Isabel Volcano. This glacier belongs to global glacier monitoring network of the World Glacier Monitoring Service (WGMS-ID: 2721). The surface mass balance is calculated monthly using the direct glaciological method. Between April 2006 and May 2014, Conejeras Glacier showed a cumulative loss of -21 m w.e. The CATCOS Project allowed to improve the glacier monitoring system in Colombia with two main actions: (1) a terrestrial laser scanner survey (RIEGL VZ-6000 terrestrial laser scanner, property of Universities of Lausanne and Fribourg); and (2) ice thickness measurements (Blue System Integration Ltd. Ice Penetrating Radar of property of IRD). The terrestrial laser-scanning survey allowed to realize an accurate digital terrain model of the glacier surface with 13 million points and a decimetric resolution. Ice thickness measurements showed an average glacier thickness of 22 meters and a maximum of 52 meters.

  2. A method for mapping corn using the US Geological Survey 1992 National Land Cover Dataset

    USGS Publications Warehouse

    Maxwell, S.K.; Nuckols, J.R.; Ward, M.H.

    2006-01-01

    Long-term exposure to elevated nitrate levels in community drinking water supplies has been associated with an elevated risk of several cancers including non-Hodgkin's lymphoma, colon cancer, and bladder cancer. To estimate human exposure to nitrate, specific crop type information is needed as fertilizer application rates vary widely by crop type. Corn requires the highest application of nitrogen fertilizer of crops grown in the Midwest US. We developed a method to refine the US Geological Survey National Land Cover Dataset (NLCD) (including map and original Landsat images) to distinguish corn from other crops. Overall average agreement between the resulting corn and other row crops class and ground reference data was 0.79 kappa coefficient with individual Landsat images ranging from 0.46 to 0.93 kappa. The highest accuracies occurred in Regions where corn was the single dominant crop (greater than 80.0%) and the crop vegetation conditions at the time of image acquisition were optimum for separation of corn from all other crops. Factors that resulted in lower accuracies included the accuracy of the NLCD map, accuracy of corn areal estimates, crop mixture, crop condition at the time of Landsat overpass, and Landsat scene anomalies. ?? 2006 Elsevier B.V. All rights reserved.

  3. Horvitz-Thompson survey sample methods for estimating large-scale animal abundance

    USGS Publications Warehouse

    Samuel, M.D.; Garton, E.O.

    1994-01-01

    Large-scale surveys to estimate animal abundance can be useful for monitoring population status and trends, for measuring responses to management or environmental alterations, and for testing ecological hypotheses about abundance. However, large-scale surveys may be expensive and logistically complex. To ensure resources are not wasted on unattainable targets, the goals and uses of each survey should be specified carefully and alternative methods for addressing these objectives always should be considered. During survey design, the impoflance of each survey error component (spatial design, propofiion of detected animals, precision in detection) should be considered carefully to produce a complete statistically based survey. Failure to address these three survey components may produce population estimates that are inaccurate (biased low), have unrealistic precision (too precise) and do not satisfactorily meet the survey objectives. Optimum survey design requires trade-offs in these sources of error relative to the costs of sampling plots and detecting animals on plots, considerations that are specific to the spatial logistics and survey methods. The Horvitz-Thompson estimators provide a comprehensive framework for considering all three survey components during the design and analysis of large-scale wildlife surveys. Problems of spatial and temporal (especially survey to survey) heterogeneity in detection probabilities have received little consideration, but failure to account for heterogeneity produces biased population estimates. The goal of producing unbiased population estimates is in conflict with the increased variation from heterogeneous detection in the population estimate. One solution to this conflict is to use an MSE-based approach to achieve a balance between bias reduction and increased variation. Further research is needed to develop methods that address spatial heterogeneity in detection, evaluate the effects of temporal heterogeneity on survey

  4. Generating or developing grounded theory: methods to understand health and illness.

    PubMed

    Woods, Phillip; Gapp, Rod; King, Michelle A

    2016-06-01

    Grounded theory is a qualitative research methodology that aims to explain social phenomena, e.g. why particular motivations or patterns of behaviour occur, at a conceptual level. Developed in the 1960s by Glaser and Strauss, the methodology has been reinterpreted by Strauss and Corbin in more recent times, resulting in different schools of thought. Differences arise from different philosophical perspectives concerning knowledge (epistemology) and the nature of reality (ontology), demanding that researchers make clear theoretical choices at the commencement of their research when choosing this methodology. Compared to other qualitative methods it has ability to achieve understanding of, rather than simply describing, a social phenomenon. Achieving understanding however, requires theoretical sampling to choose interviewees that can contribute most to the research and understanding of the phenomenon, and constant comparison of interviews to evaluate the same event or process in different settings or situations. Sampling continues until conceptual saturation is reached, i.e. when no new concepts emerge from the data. Data analysis focusses on categorising data (finding the main elements of what is occurring and why), and describing those categories in terms of properties (conceptual characteristics that define the category and give meaning) and dimensions (the variations within properties which produce specificity and range). Ultimately a core category which theoretically explains how all other categories are linked together is developed from the data. While achieving theoretical abstraction in the core category, it should be logical and capture all of the variation within the data. Theory development requires understanding of the methodology not just working through a set of procedures. This article provides a basic overview, set in the literature surrounding grounded theory, for those wanting to increase their understanding and quality of research output. PMID

  5. Assessing subsurface strata using geophysical and geotechnical methods for designing structures near ground cracks

    NASA Astrophysics Data System (ADS)

    AlFouzan, F.; Dafalla, M.; Mutaz, E.

    2012-04-01

    This paper presents a combined approach using both geophysical and geotechnical approaches to study and evaluate the subsurface strata near ground for sites suffering from faults and cracks. It demonstrates how both techniques can be utilized to gather useful information for design geotechnical engineers. The safe distance for construction close to a ground crack is mainly dependant on the subsurface stratification and the engineering properties of underlying soils or rocks. Other factors include the area geology and concepts of safety margins. This study is carried out for a site in Al-Qassim region, Saudi Arabia. This type of faults and cracks can normally occur due to a geological or physical event or due to the nature and properties of the subsurface material. The geotechnical works included advancing rotary boreholes to depths of 25m to 31m with sampling and testing. The geophysical method used included performing 2D electrical resistivity profiles. The results of geophysical and geotechnical works showed good and close agreement. The use of 2D electrical resistivity was found useful to establish the layer thicknesses of shale and highly plastic clay. This cannot be determined without deep and expensive direct boring investigation. The results showed that a thick layer of expansive soil, which is considered a high-risk soil type containing large percentage of highly plastic clay materials, underlies the site. The volume changes due to humidity variations can result in either swelling or shrinking. These changes can have significant impact on engineering structures such as light buildings and roads. The logic of placing structures in close vicinity of the cracks is based on lateral stresses exerted on the crack face. The layer thickness is a detrimental factor to establish a safe design distance. Stress distribution analysis procedure is explained.

  6. U.S. Geological Survey laboratory method for methyl tert-Butyl ether and other fuel oxygenates

    USGS Publications Warehouse

    Raese, Jon W.; Rose, Donna L.; Sandstrom, Mark W.

    1995-01-01

    Methyl tert-butyl ether (MTBE) was found in shallow ground-water samples in a study of 8 urban and 20 agricultural areas throughout the United States in 1993 and 1994 (Squillace and others, 1995, p. 1). The compound is added to gasoline either seasonally or year round in many parts of the United States to increase the octane level and to reduce carbon monoxide and ozone levels in the air. The U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL), near Denver, uses state-of-the-art technology to analyze samples for MTBE as part of the USGS water-quality studies. In addition, the NWQL offers custom analyses to determine two other fuel oxygenates--ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME). The NWQL was not able to obtain a reference standard for tert-amyl ethyl ether (TAEE), another possible fuel oxygenate (Shelley and Fouhy, 1994, p. 63). The shallow ground-water samples were collected as part of the USGS National Water-Quality Assessment Program. These samples were collected from 211 urban wells or springs and 562 agricultural wells sampled by the USGS in 1993 and 1994. The wells were keyed to specific land-use areas to assess the effects of different uses on ground-water quality (Squillace and others, 1995, p. 2). Ground-water samples were preserved on site to pH less than or equal to 2 with a solution of 1:1 hydrochloric acid. All samples were analyzed at the NWQL within 2 weeks after collection. The purpose of this fact sheet is to explain briefly the analytical method implemented by the USGS for determining MTBE and other fuel oxygenates. The scope is necessarily limited to an overview of the analytical method (instrumentation, sample preparation, calibration and quantitation, identification, and preservation of samples) and method performance (reagent blanks, accuracy, and precision).

  7. Evaluation of the US Geological Survey ground-water data-collection program in Hawaii, 1992. Water-resources investigations

    SciTech Connect

    Anthony, S.S.

    1997-12-31

    This report describes an evaluation of the 1992 USGS ground-water data-collection program in Hawaii. The occurrence of ground water in the Hawaiian islands is briefly described. Objectives for the data-collection program are identified followed by a description of well networks needed to prepare maps of water levels and chloride concentrations. For the islands of Oahu, Kauai, Maui, Molokai, and Hawaii, the wells in the 1992 ground-water data-collection program are described followed by maps showing the distribution and magnitude of pumpage, and the distribution of proposed pumped wells. Wells in the 1992 USGS ground-water data-collection program that provide useful data for mapping water levels and chloride concentrations are identified followed by locations where additional wells are needed for water-level and chloride-concentration data. In addition, a procedure to store and review data is described.

  8. Perspective ground-based method for diagnostics of the lower ionosphere and the neutral atmosphere

    NASA Astrophysics Data System (ADS)

    Bakhmetieva, N. V.; Grigoriev, G. I.; Tolmacheva, A. V.

    We present a new perspective ground-based method for diagnostics of the ionosphere and atmosphere parameters. The method uses one of the numerous physical phenomena observed in the ionosphere illuminated by high-power radio waves. It is a generation of the artificial periodic irregularities (APIs) in the ionospheric plasma. The APIs were found while studying the effects of ionospheric high-power HF modification. It was established that the APIs are formed by a standing wave that occurs due to interference between the upwardly radiated radio wave and its reflection off the ionosphere. The API studies are based upon observation of the Bragg backscatter of the pulsed probe radio wave from the artificial periodic structure. Bragg backscatter occurs if the spatial period of the irregularities is equal to half a wavelength of the probe signal. The API techniques makes it possible to obtain the following information: the profiles of electron density from the lower D-region up to the maximum of the F-layer; the irregular structure of the ionosphere including split of the regular E-layer, the sporadic layers; the vertical velocities in the D- and E-regions of the ionosphere; the turbulent velocities, turbulent diffusion coefficients and the turbopause altitude; the neutral temperatures and densities at the E-region altitudes; the parameters of the internal gravity waves and their spectral characteristics; the relative concentration of negative oxygen ions in the D-region. Some new results obtained by the API technique are discussed .

  9. Efficient continuous-time quantum Monte Carlo method for the ground state of correlated fermions

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Iazzi, Mauro; Corboz, Philippe; Troyer, Matthias

    2015-06-01

    We present the ground state extension of the efficient continuous-time quantum Monte Carlo algorithm for lattice fermions of M. Iazzi and M. Troyer, Phys. Rev. B 91, 241118 (2015), 10.1103/PhysRevB.91.241118. Based on continuous-time expansion of an imaginary-time projection operator, the algorithm is free of systematic error and scales linearly with projection time and interaction strength. Compared to the conventional quantum Monte Carlo methods for lattice fermions, this approach has greater flexibility and is easier to combine with powerful machinery such as histogram reweighting and extended ensemble simulation techniques. We discuss the implementation of the continuous-time projection in detail using the spinless t -V model as an example and compare the numerical results with exact diagonalization, density matrix renormalization group, and infinite projected entangled-pair states calculations. Finally we use the method to study the fermionic quantum critical point of spinless fermions on a honeycomb lattice and confirm previous results concerning its critical exponents.

  10. Determining concentrations of 2-bromoallyl alcohol and dibromopropene in ground water using quantitative methods

    USGS Publications Warehouse

    Panshin, Sandra Y.

    1997-01-01

    A method for determining levels of 2-bromoallyl alcohol and 2,3-dibromopropene from ground-water samples using liquid/liquid extraction followed by gas chromatography/mass spectrometry is described. Analytes were extracted from the water using three aliquots of dichloromethane. The aliquots were combined and reduced in volume by rotary evaporation followed by evaporation using a nitrogen stream. The extracts were analyzed by capillary-column gas chromatography/mass spectrometry in the full-scan mode. Estimated method detection limits were 30 nanograms per liter for 2-bromoallyl alcohol and 10 nanograms per liter for 2,3-dibromopropene. Recoveries were determined by spiking three matrices at two concentration levels (0.540 and 5.40 micrograms per liter for 2-bromoallyl alcohol; and 0.534 and 5.34micro-grams per liter for dibromopropene). For seven replicates of each matrix at the high concentration level, the mean percent recoveries ranged from 43.9 to 64.9 percent for 2-bromoallyl alcohol, and from 87.5 to 99.3 percent for dibromopropene. At the low concentration level, the mean percent recoveries ranged from 43.8 to 95.2 percent for 2-bromoallyl alcohol, and from 71.3 to 84.9 percent for dibromopropene.

  11. Laser optoacoustic method for quantitative nondestructive evaluation of the subsurface damage depth in ground silicon wafers

    NASA Astrophysics Data System (ADS)

    Podymova, N. B.; Karabutov, A. A.; Cherepetskaya, E. B.

    2014-08-01

    This paper is a report on the novel laser optoacoustic method for nondestructive evaluation of the depth of the subsurface damage in ground single-crystal silicon wafers. It is based on different mechanisms of laser excitation of ultrasound by absorption of Q-switched Nd:YAG laser pulses at the fundamental wavelength: the concentration-deformation mechanism in the undamaged single-crystal silicon and the thermoelastic one in the subsurface damaged layer. Due to the uniform heating of the whole damaged layer during the laser pulse action the amplitude of the compression phase of the laser-induced ultrasonic signal is proportional to the damaged depth. The rarefaction phase of this signal arises by absorption of the remaining laser energy in the single-crystal silicon beneath the damaged layer. The empirical relation between the depth of the subsurface damage and the ratio of the amplitudes of compression and rarefaction phases of the laser-induced ultrasonic signal can be fitted by a linear function within the depth variation and the corresponding spread of the signal amplitudes. The proposed method attracts some interest for in situ control of the solid surface condition that is important in different tasks of linear and nonlinear optics.

  12. The swift UVOT stars survey. I. Methods and test clusters

    SciTech Connect

    Siegel, Michael H.; Porterfield, Blair L.; Linevsky, Jacquelyn S.; Bond, Howard E.; Hoversten, Erik A.; Berrier, Joshua L.; Gronwall, Caryl A.; Holland, Stephen T.; Breeveld, Alice A.; Brown, Peter J. E-mail: blp14@psu.edu E-mail: caryl@astro.psu.edu E-mail: aab@mssl.ucl.ac.uk

    2014-12-01

    We describe the motivations and background of a large survey of nearby stellar populations using the Ultraviolet Optical Telescope (UVOT) on board the Swift Gamma-Ray Burst Mission. UVOT, with its wide field, near-UV sensitivity, and 2.″3 spatial resolution, is uniquely suited to studying nearby stellar populations and providing insight into the near-UV properties of hot stars and the contribution of those stars to the integrated light of more distant stellar populations. We review the state of UV stellar photometry, outline the survey, and address problems specific to wide- and crowded-field UVOT photometry. We present color–magnitude diagrams of the nearby open clusters M67, NGC 188, and NGC 2539, and the globular cluster M79. We demonstrate that UVOT can easily discern the young- and intermediate-age main sequences, blue stragglers, and hot white dwarfs, producing results consistent with previous studies. We also find that it characterizes the blue horizontal branch of M79 and easily identifies a known post-asymptotic giant branch star.

  13. First National Survey of Lead and Allergens in Housing: survey design and methods for the allergen and endotoxin components.

    PubMed Central

    Vojta, Patrick J; Friedman, Warren; Marker, David A; Clickner, Robert; Rogers, John W; Viet, Susan M; Muilenberg, Michael L; Thorne, Peter S; Arbes, Samuel J; Zeldin, Darryl C

    2002-01-01

    From July 1998 to August 1999, the U.S. Department of Housing and Urban Development and the National Institute of Environmental Health Sciences conducted the first National Survey of Lead and Allergens in Housing. The purpose of the survey was to assess children's potential household exposure to lead, allergens, and bacterial endotoxins. We surveyed a sample of 831 homes, representing 96 million permanently occupied, noninstitutional housing units that permit resident children. We administered questionnaires to household members, made home observations, and took environmental samples. This article provides general background information on the survey, an overview of the survey design, and a description of the data collection and laboratory methods pertaining to the allergen and endotoxin components. We collected dust samples from a bed, the bedroom floor, a sofa or chair, the living room floor, the kitchen floor, and a basement floor and analyzed them for cockroach allergen Bla g 1, the dust mite allergens Der f 1 and Der p 1, the cat allergen Fel d 1, the dog allergen Can f 1, the rodent allergens Rat n 1 and mouse urinary protein, allergens of the fungus Alternaria alternata, and endotoxin. This article provides the essential context for subsequent reports that will describe the prevalence of allergens and endotoxin in U.S. households, their distribution by various housing characteristics, and their associations with allergic diseases such as asthma and rhinitis. PMID:12003758

  14. COMPARISON OF GEOSTATISTICAL METHODS FOR ESTIMATING VIRUS INACTIVATION RATES IN GROUND WATER

    EPA Science Inventory

    Enteric viruses are responsible for a large number of ground-waterborne disease outbreaks every year. Septic tanks are the most frequently cited causes of ground-water contamination in disease outbreaks. Controlling the placement of septic tanks such that all viruses would be non...

  15. Comparing Coral Reef Survey Methods. Unesco Reports in Marine Science No. 21 Report of a Regional Unesco/UNEP Workshop on Coral Reef Survey Management and Assessment Methods in Asia and the Pacific (Phuket, Thailand, December 13-17, 1982).

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Marine Sciences.

    This report includes nine papers prepared for a workshop on coral reef survey management and assessment methods in Asia and the Pacific. The papers are: "A Contrast in Methodologies between Surveying and Testing" (Charles Birkeland); "Coral Reef Survey Methods in the Andaman Sea" (Hansa Chansang); "A Review of Coral Reef Survey and Management…

  16. A hybrid method of simulating broadband ground motion : A case study of the 2006 Pingtung earthquake, Taiwan

    NASA Astrophysics Data System (ADS)

    Yen, Y.; Ma, K.; Cheng, C.; Shao, K.; Lin, P.

    2011-12-01

    For the demand of engineering, the time-history of ground motions which consider the reliability and earthquake physical characters have been provided for earthquake resistant design of important building structures. However, the high frequency portion ( > 1 Hz) of near-fault ground motions was restricted by the insufficient resolution of velocity structure. Considering the relative small events which contain path and site effect in waveforms as Green's functions (i.e. empirical Green's function (EGF) method) can resolve the problem of lack of precise velocity structure to replace the path effect evaluation. Alternatively, a stochastic Green's function (SGF) method can be employed when the EGF is unavailable. Further, the low frequency ( < 1 Hz) can be obtained numerically by the Frequency-Wavenumber (FK) method. Thus, broadband frequency strong ground motion can be calculation by a hybrid method that combining a deterministic FK method for the low frequency simulation and the EGF or SGF method for high frequency simulation. The slip models had been investigated from Taiwan dense strong motion and global teleseismic data. Characterizing the slip models derived from the waveform inversion can directly extract the source parameters needed for the ground motion prediction in the EGF method or the SGF method. The nuclear power plant in southern tip of Taiwan was experienced a strong shaking by the 26 December 2006 Pingtung, Taiwan offshore earthquake. The closest strong motion station of the Central Weather Bureau, KAU082, recorded the peak acceleration value (PGA) of 0.24 g. We considered the adjacent stations to be the case study for possibility evaluation of predicting ground motion utilizing the EGF method or SGF method. The possible damage impact toward nuclear power plant for specific sites can be estimated and verified according to the simulation results

  17. Comparison of two methods for delineating land use near monitoring wells used for assessing quality of shallow ground water

    USGS Publications Warehouse

    Lorenz, D.L.; Goldstein, R.M.; Cowdery, T.K.; Stoner, J.D.

    2003-01-01

    Two methods were compared for delineating land use near shallow monitoring wells. These wells were used to assess the effects of agricultural cropland on the quality of recently recharged ground water in two sand and gravel aquifers located near land surface. The two methods for delineating land use near wells were (1) the sector method, which used potentiometric-surface maps to estimate average flow direction and a ground-water-flow model to estimate maximum length of contributing area to the monitoring well within an upgradient sector; and (2) the circle method, which used a 500- meter radius circle around the well based on a national empirical analysis. Land uses were compiled for 29 wells in each of two surficial aquifers in the Red River of the North Basin within the area defined by each method. Land use near each well was interpreted from orthorectified photographs and site inspection for both delineation methods. Land use near individual wells characterized by each method varied greatly, which can affect the results of statistical correlations between land use and water quality. Land use determined by the circle method related more closely to the land use for each entire study area. Land use determined by the sector method (within 200 meters from the wells) compared more favorably to ground-water quality based on nitrate concentrations. The maximum length of contributing areas to wells estimated in this study may be of value for other studies of unconsolidated sand and gravel aquifers with similar hydrogeological characteristics of permeability, water-table slopes, recharge, and depth to water. The additional effort required for estimating the model delineation of land use and land cover for the sector method must be weighed against the improved confidence in statistical correlation between land use and the quality of shallow ground water. Improved scientific confidence and understanding of relations between land use and quality of ground water may encourage

  18. An historical survey of computational methods in optimal control.

    NASA Technical Reports Server (NTRS)

    Polak, E.

    1973-01-01

    Review of some of the salient theoretical developments in the specific area of optimal control algorithms. The first algorithms for optimal control were aimed at unconstrained problems and were derived by using first- and second-variation methods of the calculus of variations. These methods have subsequently been recognized as gradient, Newton-Raphson, or Gauss-Newton methods in function space. A much more recent addition to the arsenal of unconstrained optimal control algorithms are several variations of conjugate-gradient methods. At first, constrained optimal control problems could only be solved by exterior penalty function methods. Later algorithms specifically designed for constrained problems have appeared. Among these are methods for solving the unconstrained linear quadratic regulator problem, as well as certain constrained minimum-time and minimum-energy problems. Differential-dynamic programming was developed from dynamic programming considerations. The conditional-gradient method, the gradient-projection method, and a couple of feasible directions methods were obtained as extensions or adaptations of related algorithms for finite-dimensional problems. Finally, the so-called epsilon-methods combine the Ritz method with penalty function techniques.

  19. Elevation Change of Drangajokull, Iceland, from Cloud-Cleared ICESat Repeat Profiles and GPS Ground-Survey Data

    NASA Technical Reports Server (NTRS)

    Shuman, Christopher A.; Sigurdsson, Oddur; Williams, Richard, Jr.; Hall, Dorothy K.

    2009-01-01

    Located on the Vestfirdir Northwest Fjords), DrangaJokull is the northernmost ice map in Iceland. Currently, the ice cap exceeds 900 m in elevation and covered an area of approx.l46 sq km in August 2004. It was about 204 sq km in area during 1913-1914 and so has lost mass during the 20th century. Drangajokull's size and accessibility for GPS surveys as well as the availability of repeat satellite altimetry profiles since late 2003 make it a good subject for change-detection analysis. The ice cap was surveyed by four GPS-equipped snowmobiles on 19-20 April 2005 and has been profiled in two places by Ice, Cloud. and land Elevation Satellite (ICESat) 'repeat tracks,' fifteen times from late to early 2009. In addition, traditional mass-balance measurements have been taken seasonally at a number of locations across the ice cap and they show positive net mass balances in 2004/2005 through 2006/2007. Mean elevation differences between the temporally-closest ICESat profiles and the GPS-derived digital-elevation model (DEM)(ICESat - DEM) are about 1.1 m but have standard deviations of 3 to 4 m. Differencing all ICESat repeats from the DEM shows that the overall elevation difference trend since 2003 is negative with losses of as much as 1.5 m/a from same season to same season (and similar elevation) data subsets. However, the mass balance assessments by traditional stake re-measurement methods suggest that the elevation changes where ICESat tracks 0046 and 0307 cross Drangajokull are not representative of the whole ice cap. Specifically, the area has experienced positive mass balance years during the time frame when ICESat data indicates substantial losses. This analysis suggests that ICESat-derived elevations may be used for multi-year change detection relative to other data but suggests that large uncertainties remain. These uncertainties may be due to geolocation uncertainty on steep slopes and continuing cloud cover that limits temporal and spatial coverage across the

  20. Application of a method for the automatic detection and Ground-Based Velocity Track Display (GBVTD) analysis of a tornado crossing the Hong Kong International Airport

    NASA Astrophysics Data System (ADS)

    Chan, P. W.; Wurman, J.; Shun, C. M.; Robinson, P.; Kosiba, K.

    2012-03-01

    A weak tornado with a maximum Doppler velocity shear of about 40 m s - 1 moved across the Hong Kong International Airport (HKIA) during the evening of 20 May 2002. The tornado caused damage equivalent to F0 on the Fujita Scale, based on a damage survey. The Doppler velocity data from the Hong Kong Terminal Doppler Weather Radar (TDWR) are studied using the Ground-Based Velocity Track Display (GBVTD) method of single Doppler analysis. The GBVTD analysis is able to clearly depict the development and decay of the tornado though it appears to underestimate its magnitude. In the pre-tornadic state, the wind field is characterized by inflow toward the center near the ground and upward motion near the center. When the tornado attains its maximum strength, an eye-like structure with a downdraft appears to form in the center. Several minutes later the tornado begins to decay and outflow dominates at low levels. Assuming cyclostrophic balance, the pressure drop 200 m from the center of the tornado at its maximum strength is calculated to be about 6 hPa. To estimate the maximum ground-relative wind speed of the tornado, the TDWR's Doppler velocities are adjusted for the ratio of the sample-volume size of the radar and the radius of the tornado, resulting in a peak wind speed of 28 m s - 1 , consistent with the readings from a nearby ground-based anemometers and the F0 damage observed. An automatic tornado detection algorithm based on Doppler velocity difference (delta-V) and temporal and spatial continuity is applied to this event. The locations and the core flow radii of the tornado as determined by the automatic method and by subjective analysis agree closely.

  1. Aerothermodynamic methods for a Mars environmental survey Mars entry

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.

    1994-01-01

    Computational fluid dynamics models for the thermodynamics and transport properties used in an equilibrium version of the Langley aerothermodynamics upwind relaxation algorithm (LAURA) for Mars atmospheric entries are described. In addition, the physical models used in a nonequilibrium version of LAURA for Mars-entry flows are described. Uncertainties exist in defining constants used in the transport properties for the equilibrium model and in many of the physical models for the nonequilibrium version. Solutions from the two codes using the best available constants are examined at the Mars-entry conditions characteristics of the Mars environmental survey mission. While the flowfields are near thermal equilibrium, chemical nonequilibrium effects are present in the entry cases examined. Convective heating at the stagnation point for these flows (assuming fully catalytic wall boundary conditions) is approximately 100 W/cm(exp 2). Radiative heating is negligible.

  2. A blind deconvolution method for ground based telescopes and Fizeau interferometers

    NASA Astrophysics Data System (ADS)

    Prato, M.; La Camera, A.; Bonettini, S.; Rebegoldi, S.; Bertero, M.; Boccacci, P.

    2015-10-01

    In the case of ground-based telescopes equipped with adaptive optics systems, the point spread function (PSF) is only poorly known or completely unknown. Moreover, an accurate modeling of the PSF is in general not available. Therefore in several imaging situations the so-called blind deconvolution methods, aiming at estimating both the scientific target and the PSF from the detected image, can be useful. A blind deconvolution problem is severely ill-posed and, in order to reduce the extremely large number of possible solutions, it is necessary to introduce sensible constraints on both the scientific target and the PSF. In a previous paper we proposed a sound mathematical approach based on a suitable inexact alternating minimization strategy for minimizing the generalized Kullback-Leibler divergence, assuring global convergence. In the framework of this method we showed that an important constraint on the PSF is the upper bound which can be derived from the knowledge of its Strehl ratio. The efficacy of the approach was demonstrated by means of numerical simulations. In this paper, besides improving the previous approach by the use of a further constraint on the unknown scientific target, we extend it to the case of multiple images of the same target obtained with different PSFs. The main application we have in mind is to Fizeau interferometry. As it is known this is a special feature of the Large Binocular Telescope (LBT). Of the two expected interferometers for LBT, one, LINC-NIRVANA, is forthcoming while the other, LBTI, is already operating and has provided the first Fizeau images, demonstrating the possibility of reaching the resolution of a 22.8 m telescope. Therefore the extension of our blind method to this imaging modality seems to be timely. The method is applied to realistic simulations of imaging both by single mirrors and Fizeau interferometers. Successes and failures of the method in the imaging of stellar fields are demonstrated in simple cases. These

  3. A comparison of survey methods to evaluate macrophyte index of biotic integrity performance in Minnesota lakes

    USGS Publications Warehouse

    Vondracek, Bruce C.; Koch, Justine D.; Beck, Marcus W.

    2014-01-01

    Aquatic macrophytes shape trophic web dynamics, provide food and refuge for macroinvertebrates and fish, and increase nutrient retention, sediment stabilization, and water clarity. Macrophytes are well-suited as indicators of ecological health because they are immobile, relatively easy to sample and identify, and respond to anthropogenic disturbance on an ecological time scale. Aquatic plant monitoring programs can provide valuable information to water resource managers, especially in conjunction with macrophyte-based indices of biotic integrity (IBI). However, there are several current sampling designs and the precision of IBI scores has not been evaluated across different surveys. We evaluated the performance of the Minnesota macrophyte-based IBI for two survey designs; a point intercept (PI) survey and a belt transect (BT) survey. PI surveys are time intensive, especially on large lakes, whereas BT are less time intensive and have been used historically in Minnesota. Our objectives were to compare the PI surveys with BT surveys on the same lakes, and to modify the BT survey (MT survey) to improve information obtained from BT surveys. BT surveys consistently overestimated IBI scores compared to the PI method (t = 6.268, df = 60, p < 0.001). Overall IBI scores calculated from MT surveys differed significantly from PI scores, but on average, MT surveys predicted scores only 3% lower than PI scores. Implementation of the Minnesota macrophyte-based IBI through the adoption of the MT survey approach would improve sampling efficiency and enable widespread documentation of the effects of landscape change, shifts in hydrologic regimes, and other anthropogenic activities on the integrity of lacustrine systems.

  4. Modern methods for calculating ground-wave field strength over a smooth spherical Earth

    NASA Astrophysics Data System (ADS)

    Eckert, R. P.

    1986-02-01

    The report makes available the computer program that produces the proposed new FCC ground-wave propagation prediction curves for the new band of standard broadcast frequencies between 1605 and 1705 kHz. The curves are included in recommendations to the U.S. Department of State in preparation for an International Telecommunication Union Radio Conference. The history of the FCC curves is traced from the early 1930's, when the Federal Radio Commission and later the FFC faced an intensifying need for technical information concerning interference distances. A family of curves satisfactorily meeting this need was published in 1940. The FCC reexamined the matter recently in connection with the planned expansion of the AM broadcast band, and the resulting new curves are a precise representation of the mathematical theory. Mathematical background is furnished so that the computer program can be critically evaluated. This will be particularly valuable to persons implementing the program on other computers or adapting it for special applications. Technical references are identified for each of the formulas used by the program, and the history of the development of mathematical methods is outlined.

  5. Petrophysical analysis of geophysical logs of the National Drilling Company-U.S. Geological Survey ground-water research project for Abu Dhabi Emirate, United Arab Emirates

    USGS Publications Warehouse

    Jorgensen, Donald G.; Petricola, Mario

    1994-01-01

    A program of borehole-geophysical logging was implemented to supply geologic and geohydrologic information for a regional ground-water investigation of Abu Dhabi Emirate. Analysis of geophysical logs was essential to provide information on geohydrologic properties because drill cuttings were not always adequate to define lithologic boundaries. The standard suite of logs obtained at most project test holes consisted of caliper, spontaneous potential, gamma ray, dual induction, microresistivity, compensated neutron, compensated density, and compensated sonic. Ophiolitic detritus from the nearby Oman Mountains has unusual petrophysical properties that complicated the interpretation of geophysical logs. The density of coarse ophiolitic detritus is typically greater than 3.0 grams per cubic centimeter, porosity values are large, often exceeding 45 percent, and the clay fraction included unusual clays, such as lizardite. Neither the spontaneous-potential log nor the natural gamma-ray log were useable clay indicators. Because intrinsic permeability is a function of clay content, additional research in determining clay content was critical. A research program of geophysical logging was conducted to determine the petrophysical properties of the shallow subsurface formations. The logging included spectral-gamma and thermal-decay-time logs. These logs, along with the standard geophysical logs, were correlated to mineralogy and whole-rock chemistry as determined from sidewall cores. Thus, interpretation of lithology and fluids was accomplished. Permeability and specific yield were calculated from geophysical-log data and correlated to results from an aquifer test. On the basis of results from the research logging, a method of lithologic and water-resistivity interpretation was developed for the test holes at which the standard suite of logs were obtained. In addition, a computer program was developed to assist in the analysis of log data. Geohydrologic properties were

  6. Teaching and Assessment Methods in Undergraduate Economics: A Fourth National Quinquennial Survey

    ERIC Educational Resources Information Center

    Watts, Michael; Schaur, Georg

    2011-01-01

    Surveys in 1995, 2000, 2005, and 2010 investigated teaching and assessment methods in different undergraduate courses. In this article, the authors offer basic results from the 2010 survey. "Chalk and talk" remains the dominant teaching style, but there were drops in mean (although not median) values for those pedagogies and some growth in the use…

  7. The JCMT Gould Belt Survey: a quantitative comparison between SCUBA-2 data reduction methods

    NASA Astrophysics Data System (ADS)

    Mairs, S.; Johnstone, D.; Kirk, H.; Graves, S.; Buckle, J.; Beaulieu, S. F.; Berry, D. S.; Broekhoven-Fiene, H.; Currie, M. J.; Fich, M.; Hatchell, J.; Jenness, T.; Mottram, J. C.; Nutter, D.; Pattle, K.; Pineda, J. E.; Salji, C.; Francesco, J. Di; Hogerheijde, M. R.; Ward-Thompson, D.; JCMT Gould Belt survey Team

    2015-12-01

    Performing ground-based submillimetre observations is a difficult task as the measurements are subject to absorption and emission from water vapour in the Earth's atmosphere and time variation in weather and instrument stability. Removing these features and other artefacts from the data is a vital process which affects the characteristics of the recovered astronomical structure we seek to study. In this paper, we explore two data reduction methods for data taken with the Submillimetre Common-User Bolometer Array-2 (SCUBA-2) at the James Clerk Maxwell Telescope (JCMT). The JCMT Legacy Reduction 1 (JCMT LR1) and The Gould Belt Legacy Survey Legacy Release 1 (GBS LR1) reduction both use the same software (STARLINK) but differ in their choice of data reduction parameters. We find that the JCMT LR1 reduction is suitable for determining whether or not compact emission is present in a given region and the GBS LR1 reduction is tuned in a robust way to uncover more extended emission, which better serves more in-depth physical analyses of star-forming regions. Using the GBS LR1 method, we find that compact sources are recovered well, even at a peak brightness of only three times the noise, whereas the reconstruction of larger objects requires much care when drawing boundaries around the expected astronomical signal in the data reduction process. Incorrect boundaries can lead to false structure identification or it can cause structure to be missed. In the JCMT LR1 reduction, the extent of the true structure of objects larger than a point source is never fully recovered.

  8. Ground Albedo Neutron Sensing (GANS) method for measurements of soil moisture in cropped fields

    NASA Astrophysics Data System (ADS)

    Andres Rivera Villarreyes, Carlos; Baroni, Gabriele; Oswald, Sascha E.

    2013-04-01

    Measurement of soil moisture at the plot or hill-slope scale is an important link between local vadose zone hydrology and catchment hydrology. However, so far only few methods are on the way to close this gap between point measurements and remote sensing. This study evaluates the applicability of the Ground Albedo Neutron Sensing (GANS) for integral quantification of seasonal soil moisture in the root zone at the scale of a field or small watershed, making use of the crucial role of hydrogen as neutron moderator relative to other landscape materials. GANS measurements were performed at two locations in Germany under different vegetative situations and seasonal conditions. Ground albedo neutrons were measured at (i) a lowland Bornim farmland (Brandenburg) cropped with sunflower in 2011 and winter rye in 2012, and (ii) a mountainous farmland catchment (Schaefertal, Harz Mountains) since middle 2011. At both sites depth profiles of soil moisture were measured at several locations in parallel by frequency domain reflectometry (FDR) for comparison and calibration. Initially, calibration parameters derived from a previous study with corn cover were tested under sunflower and winter rye periods at the same farmland. GANS soil moisture based on these parameters showed a large discrepancy compared to classical soil moisture measurements. Therefore, two new calibration approaches and four different ways of integration the soil moisture profile to an integral value for GANS were evaluated in this study. This included different sets of calibration parameters based on different growing periods of sunflower. New calibration parameters showed a good agreement with FDR network during sunflower period (RMSE = 0.023 m3 m-3), but they underestimated soil moisture in the winter rye period. The GANS approach resulted to be highly affected by temporal changes of biomass and crop types which suggest the need of neutron corrections for long-term observations with crop rotation. Finally

  9. 77 FR 24684 - Proposed Information Collection; Comment Request; 2013-2015 American Community Survey Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-25

    ... Methods Panel Testing AGENCY: U.S. Census Bureau. ACTION: Notice. SUMMARY: The Department of Commerce, as... materials. The ACS Methods Panel is a research program that is designed to address and respond to survey issues and needs. During the 2013-2015 period, the Methods Panel may include testing methods...

  10. A survey of surveys

    SciTech Connect

    Kent, S.M.

    1994-11-01

    A new era for the field of Galactic structure is about to be opened with the advent of wide-area digital sky surveys. In this article, the author reviews the status and prospects for research for 3 new ground-based surveys: the Sloan Digital Sky Survey (SDSS), the Deep Near-Infrared Survey of the Southern Sky (DENIS) and the Two Micron AU Sky Survey (2MASS). These surveys will permit detailed studies of Galactic structure and stellar populations in the Galaxy with unprecedented detail. Extracting the information, however, will be challenging.

  11. A survey of strength analysis methods for laminates with holes

    NASA Technical Reports Server (NTRS)

    Crews, J. H., Jr.

    1984-01-01

    The methods for predicting the strength of composite laminates with fastener holes are reviewed for the cases of unloaded as well as loaded holes. Three categories of methods are discussed: (1) the hole-boundary stress (HBS) methods which compare the peak stresses and the laminate strength; (2) the linear elastic fracture (LEFM) methods which assume cracks emanating from the hole and predict failure when the stress intensity factor for a crack equals the laminate fracture toughness; and (3) two different two-parameter (TP) methods: the average-stress (ASTP) method, which predicts failure when the average stress over a distance from the hole equals the laminate strength; and the point-stress (PSTP) Whitney-Nuismer (1974) approach, which predicts failure when the stress near the hole equals the material strength. The PSTP is relatively accurate and is by far the most widely used of all the prediction methods. However, for large ranges of variables and cases, the current strength predictions may not always be accurate.

  12. Finding a Fox: An Evaluation of Survey Methods to Estimate Abundance of a Small Desert Carnivore

    PubMed Central

    Dempsey, Steven J.; Gese, Eric M.; Kluever, Bryan M.

    2014-01-01

    The status of many carnivore species is a growing concern for wildlife agencies, conservation organizations, and the general public. Historically, kit foxes (Vulpes macrotis) were classified as abundant and distributed in the desert and semi-arid regions of southwestern North America, but is now considered rare throughout its range. Survey methods have been evaluated for kit foxes, but often in populations where abundance is high and there is little consensus on which technique is best to monitor abundance. We conducted a 2-year study to evaluate four survey methods (scat deposition surveys, scent station surveys, spotlight survey, and trapping) for detecting kit foxes and measuring fox abundance. We determined the probability of detection for each method, and examined the correlation between the relative abundance as estimated by each survey method and the known minimum kit fox abundance as determined by radio-collared animals. All surveys were conducted on 15 5-km transects during the 3 biological seasons of the kit fox. Scat deposition surveys had both the highest detection probabilities (p = 0.88) and were most closely related to minimum known fox abundance (r2 = 0.50, P = 0.001). The next best method for kit fox detection was the scent station survey (p = 0.73), which had the second highest correlation to fox abundance (r2 = 0.46, P<0.001). For detecting kit foxes in a low density population we suggest using scat deposition transects during the breeding season. Scat deposition surveys have low costs, resilience to weather, low labor requirements, and pose no risk to the study animals. The breeding season was ideal for monitoring kit fox population size, as detections consisted of the resident population and had the highest detection probabilities. Using appropriate monitoring techniques will be critical for future conservation actions for this rare desert carnivore. PMID:25148102

  13. Research of Stability Problems on Ankara-Konya High Speed Railway Line (Turkey) using Ground Penetrating Radar and Petrographical Methods

    NASA Astrophysics Data System (ADS)

    Kadioglu, S.; Kadioglu, Y. K.

    2012-04-01

    The aim of the study is to research the stability problems according to rock properties and their discontinuities such as fractures, faults and karstic cavities on the new high-speed railway line between the capital city Ankara and the largest city Konya in Turkey. The Ankara-Konya high speed railway including a tunnel managed from The Turkish State Railways (TCDD). Geological surveys, polarizing microscope and confocal Raman spectrometry studies were used to determine rock properties. Ground penetrating radar (GPR) method was used to determine faults, fractures and karstic cavities. The railway line has been mainly constructed on inner Tauride Ocean suture of the Central Anatolia. The basement unit of the railway line mainly has been composed of ophiolitic complex of the inner Tauride Ocean. The main lithology of this ophiolitic complex has been formed by radiolarite, pelagic sediments, dolarite, gabbro, serpentinized peridotite and limestone blocks. The Jurassic alloctonous limestone which has been thrust on the ophiolitic complex. Neogene cover young units with minor amount of Alluvium deposits have been formed by the upper litholgy in the region. The serpentinite and altered radiolarite formation are formed by lubricous ground for the railway line in the region. A RAMAC CUII GPR system was used with a bi-static 100 MHz center band shielded antenna to acquire profile data. Totaly 35 km was surveyed on different parts of the railway line by considering the results of the geologic research and petrograpical studies. When we started to study, rail construction of some parts of the line had already been completed. Therefore, during studies, we gathered the data on the backfilled way on the three parallel profiles spaced 1m apart or on the service way next to the railway line. There was a tunnel on the line. We also gathered two parallel profiles data on the tunnel and four profiles data next to the tunnel to evaluate the stability according to the discontinuities

  14. Passive acoustic monitoring of coastally associated Hawaiian spinner dolphins, Stenella longirostris, ground-truthed through visual surveys.

    PubMed

    Heenehan, Heather L; Tyne, Julian A; Bejder, Lars; Van Parijs, Sofie M; Johnston, David W

    2016-07-01

    Effective decision making to protect coastally associated dolphins relies on monitoring the presence of animals in areas that are critical to their survival. Hawaiian spinner dolphins forage at night and rest during the day in shallow bays. Due to their predictable presence, they are targeted by dolphin-tourism. In this study, comparisons of presence were made between passive acoustic monitoring (PAM) and vessel-based visual surveys in Hawaiian spinner dolphin resting bays. DSG-Ocean passive acoustic recording devices were deployed in four bays along the Kona Coast of Hawai'i Island between January 8, 2011 and August 30, 2012. The devices sampled at 80 kHz, making 30-s recordings every four minutes. Overall, dolphins were acoustically detected on 37.1% to 89.6% of recording days depending on the bay. Vessel-based visual surveys overlapped with the PAM surveys on 202 days across the four bays. No significant differences were found between visual and acoustic detections suggesting acoustic surveys can be used as a proxy for visual surveys. Given the need to monitor dolphin presence across sites, PAM is the most suitable and efficient tool for monitoring long-term presence/absence. Concomitant photo-identification surveys are necessary to address changes in abundance over time. PMID:27475147

  15. A Survey of Methods of Teaching Mathematics. Final Report.

    ERIC Educational Resources Information Center

    Kovach, L. D.

    Several methods of teaching college-level mathematics sequences are examined for their advantages, disadvantages, and costs. Materials considered include textbooks, film sequences, videotaped lectures, and individualized teaching machines. (SD)

  16. Survey and Chase: A New Method of Observations For The Michigan Orbital Debris Survey Telescope (MODEST)

    NASA Technical Reports Server (NTRS)

    Abercromby, Kira J.; Seitzer, Patrick; Rodriquez, Heather M.; Barker, Edwin S.; Matney, Mark J.

    2006-01-01

    For more than 40 years astronauts have been observing Earth, taking photographs or digital images from their spacecraft. Today, a robust program of observation from the International Space Station (ISS) has yielded hundreds of thousands of images of the Earth s surface collected since 2001. Seeing Earth through the eyes of an astronaut is exciting to the general public, and the images are popular in classrooms. Because the ISS has an orbital inclination of 51.6 degrees (the north-south limits of the orbit are at 51.6 degrees latitude), high latitude observations are common. Some of the most striking images collected include views of polar phenomena. Astronauts routinely pass above brilliant red and green aurora; view high, wispy clouds at the top of the atmosphere; or look down on glaciers and floating ice rafts. These images, framed and captured by humans, are easily interpreted by students and teachers. Astronaut observations provide a way to visualize complicated polar phenomena and communicate about them to students of all ages. Over the next two years, astronauts aboard the ISS will formally focus their observations on polar phenomena as participants in the International Polar Year (IPY). Imagery acquisition from the ISS will be coordinated with other IPY scientists staging studies and field campaigns on the ground. The imagery collected from the ISS will be cataloged and served on NASA s web-based database of images, http://eol.jsc.nasa.gov . The website allows investigators, students and teachers to search through the imagery, assemble image datasets, and download the imagery and the metadata. We display some of the most spectacular examples of polar imagery and demonstrate NASA s database of astronaut images of Earth.

  17. Measurement, characterization, and prediction of strong ground motion

    USGS Publications Warehouse

    Joyner, William; Boore, David M.

    1988-01-01

    A number of predictive relationships derived from regression analysis of strong-motion data are available for horizontal peak acceleration, velocity, and response spectral values. Theoretical prediction of ground motion calls for stochastic source models because source heterogeneities control the amplitude of ground motion at most, if not all, frequencies of engineering interest. Theoretical methods have been developed for estimation of ground-motion parameters and simulation of ground-motion time series. These methods are particularly helpful for regions such, as eastern North America where strong-motion data are sparse. The authors survey the field, first reviewing developments in ground-motion measurement and data processing. The authors then consider the choice of parameters for characterizing strong ground motion and describe the wave-types involved in strong ground motion and the factors affecting ground-motion amplitudes. They conclude by describing methods for predicting ground motion.

  18. Helicopter-borne and ground-towed radar surveys of the Fourcade Glacier on King George Island, Antarctica

    NASA Astrophysics Data System (ADS)

    Kim, K. Y.; Lee, J.; Hong, M. H.; Hong, J. K.; Shon, H.

    2010-02-01

    To determine subglacial topography and internal features of the Fourcade Glacier on King George Island in Antarctica, helicopter-borne and ground-towed ground-penetrating radar (GPR) data were recorded along four profiles in November 2006. Signature deconvolution, f-k migration velocity analysis, and finite-difference depth migration applied to the mixed-phase, single-channel, ground-towed data, were effective in increasing vertical resolution, obtaining the velocity function, and yielding clear depth images, respectively. For the helicopter-borne GPR, migration velocities were obtained as root-mean-squared velocities in a two-layer model of air and ice. The radar sections show rugged subglacial topography, englacial sliding surfaces, and localised scattering noise. The maximum depth to the basement is over 79m in the subglacial valley adjacent to the south-eastern slope of the divide ridge between Fourcade and Moczydlowski Glaciers. In the ground-towed profile, we interpret a complicated conduit above possible basal water and other isolated cavities, which are a few metres wide. Near the terminus, the GPR profiles image sliding surfaces, fractures, and faults that will contribute to the tidewater calving mechanism forming icebergs in Potter Cove.

  19. Collaborative study of a method for the extraction of light filth from whole, cracked, or flaked and ground spices.

    PubMed

    Glaze, L E

    1975-05-01

    An improved method has been developed for the extraction of light filth from whole, cracked, or flaked spices (basil, bay leaves, clery leaves, chervil, chives, dill weed, mint flakes, parsley, rosemary, sage, tarragon, thyme, and vegetable flakes) and from ground spices (cloves, cumin, marjoram, mustard seed, oregano, sage, and thyme). The method involves a chloroform or isopropanol defatting, followed by a direct flotation from 40% isopropanol with Tween 80-EDTA (1+1) and mineral oil-heptane (85+15). Collaborative results show that the proposed method is more rapid to perform and yields better filth recoveries than the official first action methods for ground spices, 44.116, and whole, cracked, or flaked spices, 44.129. The method has been adopted as official first action. PMID:1170162

  20. A survey of design methods for failure detection in dynamic systems

    NASA Technical Reports Server (NTRS)

    Willsky, A. S.

    1975-01-01

    A number of methods for the detection of abrupt changes (such as failures) in stochastic dynamical systems were surveyed. The class of linear systems were emphasized, but the basic concepts, if not the detailed analyses, carry over to other classes of systems. The methods surveyed range from the design of specific failure-sensitive filters, to the use of statistical tests on filter innovations, to the development of jump process formulations. Tradeoffs in complexity versus performance are discussed.

  1. A survey of design methods for failure detection in dynamic systems

    NASA Technical Reports Server (NTRS)

    Willsky, A. S.

    1975-01-01

    A number of methods for detecting abrupt changes (such as failures) in stochastic dynamical systems are surveyed. The class of linear systems is concentrated on but the basic concepts, if not the detailed analyses, carry over to other classes of systems. The methods surveyed range from the design of specific failure-sensitive filters, to the use of statistical tests on filter innovations, to the development of jump process formulations. Tradeoffs in complexity versus performance are discussed.

  2. Calculation of broadband time histories of ground motion: Comparison of methods and validation using strong-ground motion from the 1994 Northridge earthquake

    USGS Publications Warehouse

    Hartzell, S.; Harmsen, S.; Frankel, A.; Larsen, S.

    1999-01-01

    This article compares techniques for calculating broadband time histories of ground motion in the near field of a finite fault by comparing synthetics with the strong-motion data set for the 1994 Northridge earthquake. Based on this comparison, a preferred methodology is presented. Ground-motion-simulation techniques are divided into two general methods: kinematic- and composite-fault models. Green's functions of three types are evaluated: stochastic, empirical, and theoretical. A hybrid scheme is found to give the best fit to the Northridge data. Low frequencies ( 1 Hz) are calculated using a composite-fault model with a fractal subevent size distribution and stochastic, bandlimited, white-noise Green's functions. At frequencies below 1 Hz, theoretical elastic-wave-propagation synthetics introduce proper seismic-phase arrivals of body waves and surface waves. The 3D velocity structure more accurately reproduces record durations for the deep sedimentary basin structures found in the Los Angeles region. At frequencies above 1 Hz, scattering effects become important and wave propagation is more accurately represented by stochastic Green's functions. A fractal subevent size distribution for the composite fault model ensures an ??-2 spectral shape over the entire frequency band considered (0.1-20 Hz).

  3. A survey of the broadband shock associated noise prediction methods

    NASA Technical Reports Server (NTRS)

    Kim, Chan M.; Krejsa, Eugene A.; Khavaran, Abbas

    1992-01-01

    Several different prediction methods to estimate the broadband shock associated noise of a supersonic jet are introduced and compared with experimental data at various test conditions. The nozzle geometries considered for comparison include a convergent and a convergent-divergent nozzle, both axisymmetric. Capabilities and limitations of prediction methods in incorporating the two nozzle geometries, flight effect, and temperature effect are discussed. Predicted noise field shows the best agreement for a convergent nozzle geometry under static conditions. Predicted results for nozzles in flight show larger discrepancies from data and more dependable flight data are required for further comparison. Qualitative effects of jet temperature, as observed in experiment, are reproduced in predicted results.

  4. A survey of machine learning methods for secondary and supersecondary protein structure prediction.

    PubMed

    Ho, Hui Kian; Zhang, Lei; Ramamohanarao, Kotagiri; Martin, Shawn

    2013-01-01

    In this chapter we provide a survey of protein secondary and supersecondary structure prediction using methods from machine learning. Our focus is on machine learning methods applicable to β-hairpin and β-sheet prediction, but we also discuss methods for more general supersecondary structure prediction. We provide background on the secondary and supersecondary structures that we discuss, the features used to describe them, and the basic theory behind the machine learning methods used. We survey the machine learning methods available for secondary and supersecondary structure prediction and compare them where possible. PMID:22987348

  5. Ground-penetrating radar survey on the island of Pantelleria (Italy) reveals an ancient architectural complex with likely Punic and Roman components

    NASA Astrophysics Data System (ADS)

    Urban, Thomas M.; Murray, Carrie Ann; Vella, Clive; Lahikainen, Amanda

    2015-12-01

    A ground-penetrating radar (GPR) survey conducted on the small volcanic island of Pantelleria, in the Strait of Sicily, south-central Mediterranean, revealed an apparent complex of Punic/Roman architecture. The survey focused on the Lago di Venere area, where a previously investigated ritual Punic site was built alongside a brackish volcanic lake. The site also exhibits evidence of earlier Eneolithic components and later Roman components. The full extent of the site has remained undetermined, however, with only the small area of the Punic ritual complex having been excavated from 1996 to 2002. The GPR survey was intended to explore whether additional architecture remained unseen in surrounding areas, thus taking a first step toward determining the site's full spatial extent and archaeological potential. This survey revealed a complex of architectural ruins beneath an active agricultural field immediately west of the previously excavated features, and extending to a depth of approximately 2 m. These newly discovered features expand the known architectural footprint of the immediate site by three-fold. This GPR study is the first published archaeo-geophysical investigation on the island.

  6. Comparison of visual survey and seining methods for estimating abundance of an endangered, benthic stream fish

    USGS Publications Warehouse

    Jordan, F.; Jelks, H.L.; Bortone, S.A.; Dorazio, R.M.

    2008-01-01

    We compared visual survey and seining methods for estimating abundance of endangered Okaloosa darters, Etheostoma okaloosae, in 12 replicate stream reaches during August 2001. For each 20-m stream reach, two divers systematically located and marked the position of darters and then a second crew of three to five people came through with a small-mesh seine and exhaustively sampled the same area. Visual surveys required little extra time to complete. Visual counts (24.2 ?? 12.0; mean ?? one SD) considerably exceeded seine captures (7.4 ?? 4.8), and counts from the two methods were uncorrelated. Visual surveys, but not seines, detected the presence of Okaloosa darters at one site with low population densities. In 2003, we performed a depletion removal study in 10 replicate stream reaches to assess the accuracy of the visual survey method. Visual surveys detected 59% of Okaloosa darters present, and visual counts and removal estimates were positively correlated. Taken together, our comparisons indicate that visual surveys more accurately and precisely estimate abundance of Okaloosa darters than seining and more reliably detect presence at low population densities. We recommend evaluation of visual survey methods when designing programs to monitor abundance of benthic fishes in clear streams, especially for threatened and endangered species that may be sensitive to handling and habitat disturbance. ?? 2007 Springer Science+Business Media, Inc.

  7. Computer Program for Thin Wire Antenna over a Perfectly Conducting Ground Plane. [using Galerkins method and sinusoidal bases

    NASA Technical Reports Server (NTRS)

    Richmond, J. H.

    1974-01-01

    A computer program is presented for a thin-wire antenna over a perfect ground plane. The analysis is performed in the frequency domain, and the exterior medium is free space. The antenna may have finite conductivity and lumped loads. The output data includes the current distribution, impedance, radiation efficiency, and gain. The program uses sinusoidal bases and Galerkin's method.

  8. EFFECTS OF GROUND ULV (ULTRA-LOW VOLUME) APPLICATIONS OF FENTHION ON ESTUARINE BIOTA. 2. ANALYTICAL METHODS AND RESULTS

    EPA Science Inventory

    Methods of analyses were validated for quantitating fenthion residues in samples from two salt marsh sites subjected to ground ultra-low volume sprays. Concentrations of these residues were followed from the water's surface, through the water column and onto the sediment. For all...

  9. NCES Handbook of Survey Methods. NCES 2011-609

    ERIC Educational Resources Information Center

    Burns, Shelley, Ed.; Wang, Xiaolei, Ed.; Henning, Alexandra, Ed.

    2011-01-01

    Since its inception, the National Center for Education Statistics (NCES) has been committed to the practice of documenting its statistical methods for its customers and of seeking to avoid misinterpretation of its published data. The reason for this policy is to assure customers that proper statistical standards and techniques have been observed,…

  10. A Survey of Methods in the Human Potential Movement

    ERIC Educational Resources Information Center

    Margolis, Fredric

    1977-01-01

    Training methods which affect the mind, body consciousness, values, and purpose of life, according to this article, include biofeedback, extrasensory perception, Yoga, transcendental meditation, and Zen. The article describes some elements common to these systems, lists a number of the systems with their costs, and gives some considerations in…

  11. Method for validating cloud mask obtained from satellite measurements using ground-based sky camera.

    PubMed

    Letu, Husi; Nagao, Takashi M; Nakajima, Takashi Y; Matsumae, Yoshiaki

    2014-11-01

    Error propagation in Earth's atmospheric, oceanic, and land surface parameters of the satellite products caused by misclassification of the cloud mask is a critical issue for improving the accuracy of satellite products. Thus, characterizing the accuracy of the cloud mask is important for investigating the influence of the cloud mask on satellite products. In this study, we proposed a method for validating multiwavelength satellite data derived cloud masks using ground-based sky camera (GSC) data. First, a cloud cover algorithm for GSC data has been developed using sky index and bright index. Then, Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data derived cloud masks by two cloud-screening algorithms (i.e., MOD35 and CLAUDIA) were validated using the GSC cloud mask. The results indicate that MOD35 is likely to classify ambiguous pixels as "cloudy," whereas CLAUDIA is likely to classify them as "clear." Furthermore, the influence of error propagations caused by misclassification of the MOD35 and CLAUDIA cloud masks on MODIS derived reflectance, brightness temperature, and normalized difference vegetation index (NDVI) in clear and cloudy pixels was investigated using sky camera data. It shows that the influence of the error propagation by the MOD35 cloud mask on the MODIS derived monthly mean reflectance, brightness temperature, and NDVI for clear pixels is significantly smaller than for the CLAUDIA cloud mask; the influence of the error propagation by the CLAUDIA cloud mask on MODIS derived monthly mean cloud products for cloudy pixels is significantly smaller than that by the MOD35 cloud mask. PMID:25402920

  12. A method for retrieving the cumulus entrainment rate from ground based observations

    NASA Astrophysics Data System (ADS)

    Wagner, Timothy J.

    2011-12-01

    The entrainment of drier environmental air into cumulus clouds affects the impact that these clouds have on the environment by modifying their radiative, microphysical, and thermodynamic characteristics. Entrainment is a difficult parameter to observe directly, and heretofore has been obtained from occasional aircraft penetrations. To increase the number of cumulus entrainment rate observations under a wide range of atmospheric conditions, an algorithm for retrieving the cumulus entrainment rate from ground-based remote sensing observations has been developed. This algorithm, called the Entrainment Rate In Cumulus Algorithm (ERICA), uses the suite of instruments at the Southern Great Plains (SGP) site of the United States Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility as inputs into a Gauss-Newton optimal estimation scheme. The forward model in this algorithm is the Explicit Mixing Parcel Model (EMPM), a cloud parcel model that treats entrainment as a series of discrete mixing events. Output from EMPM is used to calculate quantities that can be observed from the surface, including effective radius and liquid water path. The entrainment rate in EMPM is adjusted iteratively until the modeled output converges to the observations. Sensitivity testing and error and information content analysis show that ERICA is a robust method for obtaining accurate estimates of entrainment rate without the drawbacks of aircraft observations. Results from a three-month trial of ERICA show significant variability of the entrainment rate of clouds in a single day and from one day to the next. The mean value from this analysis corresponds well with prior knowledge of the entrainment rate.

  13. A survey of numerical methods for shock physics applications

    SciTech Connect

    Hertel, E.S. Jr.

    1997-10-01

    Hydrocodes or more accurately, shock physics analysis packages, have been widely used in the US Department of Energy (DOE) laboratories and elsewhere around the world for over 30 years. Initial applications included weapons effects studies where the pressure levels were high enough to disregard the material strength, hence the term hydrocode. Over the last 30 years, Sandia has worked extensively to develop and apply advanced hydrocodes to armor/anti-armor interactions, warhead design, high explosive initiation, and nuclear weapon safety issues. The needs of the DOE have changed over the last 30 years, especially over the last decade. A much stronger emphasis is currently placed on the details of material deformation and high explosive initiation phenomena. The hydrocodes of 30 years ago have now evolved into sophisticated analysis tools that can replace testing in some situations and complement it in all situations. A brief history of the development of hydrocodes in the US will be given. The author also discusses and compares the four principal methods in use today for the solution of the conservation equations of mass, momentum, and energy for shock physics applications. The techniques discussed are the Eulerian methods currently employed by the Sandia multi-dimensional shock physics analysis package known as CTH; the element based Lagrangian method currently used by codes like DYNA; the element free Lagrangian method (also known as smooth particle hydrodynamics) used by codes like the Los Alamos code SPHINX; and the Arbitrary Lagrangian Eulerian methods used by codes like the Lawrence Livermore code CALE or the Sandia code ALEGRA.

  14. Evaluation of culture- and PCR-based detection methods for Escherichia coli O157:H7 in inoculated ground beeft.

    PubMed

    Arthur, Terrance M; Bosilevac, Joseph M; Nou, Xiangwu; Koohmaraie, Mohammad

    2005-08-01

    Currently, several beef processors employ test-and-hold systems for increased quality control of ground beef. In such programs, each lot of product must be tested and found negative for Escherichia coli O157:H7 prior to release of the product into commerce. Optimization of three testing attributes (detection time, specificity, and sensitivity) is critical to the success of such strategies. Because ground beef is a highly perishable product, the testing methodology used must be as rapid as possible. The test also must have a low false-positive result rate so product is not needlessly discarded. False-negative results cannot be tolerated because they would allow contaminated product to be released and potentially cause disease. In this study, two culture-based and three PCR-based methods for detecting E. coli O157:H7 in ground beef were compared for their abilities to meet the above criteria. Ground beef samples were individually spiked with five genetically distinct strains of E. coli O157: H7 at concentrations of 17 and 1.7 CFU/65 g and then subjected to the various testing methodologies. There was no difference (P > 0.05) in the abilities of the PCR-based methods to detect E. coli O157:H7 inoculated in ground beef at 1.7 CFU/65 g. The culture-based systems detected more positive samples than did the PCR-based systems, but the detection times (21 to 48 h) were at least 9 h longer than those for the PCR-based methods (7.5 to 12 h). Ground beef samples were also spiked with potentially cross-reactive strains. The PCR-based systems that employed an immunomagnetic separation step prior to detection produced fewer false-positive results. PMID:21132961

  15. A Delphi Method Analysis to Create an Emergency Medicine Educational Patient Satisfaction Survey

    PubMed Central

    London, Kory S.; Singal, Bonita; Fowler, Jennifer; Prepejchal, Rebecca; Simmons, Stefanie; Finefrock, Douglas

    2015-01-01

    Introduction Feedback on patient satisfaction (PS) as a means to monitor and improve performance in patient communication is lacking in residency training. A physician’s promotion, compensation and job satisfaction may be impacted by his individual PS scores, once he is in practice. Many communication and satisfaction surveys exist but none focus on the emergency department setting for educational purposes. The goal of this project was to create an emergency medicine-based educational PS survey with strong evidence for content validity. Methods We used the Delphi Method (DM) to obtain expert opinion via an iterative process of surveying. Questions were mined from four PS surveys as well as from group suggestion. The DM analysis determined the structure, content and appropriate use of the tool. The group used four-point Likert-type scales and Lynn’s criteria for content validity to determine relevant questions from the stated goals. Results Twelve recruited experts participated in a series of seven surveys to achieve consensus. A 10-question, single-page survey with an additional page of qualitative questions and demographic questions was selected. Thirty one questions were judged to be relevant from an original 48-question list. Of these, the final 10 questions were chosen. Response rates for individual survey items was 99.5%. Conclusion The DM produced a consensus survey with content validity evidence. Future work will be needed to obtain evidence for response process, internal structure and construct validity. PMID:26759663

  16. A survey of synchronization methods for parallel computers

    SciTech Connect

    Dinning, A. )

    1989-07-01

    This article examines how traditional synchronization methods influence the design of MIMD multiprocessors. This particular class of architectures is one in which high-level synchronization plays an important role. Although vector processors, dataflow machines, and single instruction, multiple-data (SIMD) computers are highly synchronized, their synchronization is generally an explicit part of the control flow and is executed as part of every instruction. In MIMD multiprocessors, synchronization must occur on demand, so more sophisticated schemes are needed.

  17. Survey and analysis of multiresolution methods for turbulence data

    DOE PAGESBeta

    Pulido, Jesus; Livescu, Daniel; Woodring, Jonathan; Ahrens, James; Hamann, Bernd

    2015-11-10

    This paper compares the effectiveness of various multi-resolution geometric representation methods, such as B-spline, Daubechies, Coiflet and Dual-tree wavelets, curvelets and surfacelets, to capture the structure of fully developed turbulence using a truncated set of coefficients. The turbulence dataset is obtained from a Direct Numerical Simulation of buoyancy driven turbulence on a 5123 mesh size, with an Atwood number, A = 0.05, and turbulent Reynolds number, Ret = 1800, and the methods are tested against quantities pertaining to both velocities and active scalar (density) fields and their derivatives, spectra, and the properties of constant density surfaces. The comparisons between themore » algorithms are given in terms of performance, accuracy, and compression properties. The results should provide useful information for multi-resolution analysis of turbulence, coherent feature extraction, compression for large datasets handling, as well as simulations algorithms based on multi-resolution methods. In conclusion, the final section provides recommendations for best decomposition algorithms based on several metrics related to computational efficiency and preservation of turbulence properties using a reduced set of coefficients.« less

  18. Survey and analysis of multiresolution methods for turbulence data

    SciTech Connect

    Pulido, Jesus; Livescu, Daniel; Woodring, Jonathan; Ahrens, James; Hamann, Bernd

    2015-11-10

    This paper compares the effectiveness of various multi-resolution geometric representation methods, such as B-spline, Daubechies, Coiflet and Dual-tree wavelets, curvelets and surfacelets, to capture the structure of fully developed turbulence using a truncated set of coefficients. The turbulence dataset is obtained from a Direct Numerical Simulation of buoyancy driven turbulence on a 5123 mesh size, with an Atwood number, A = 0.05, and turbulent Reynolds number, Ret = 1800, and the methods are tested against quantities pertaining to both velocities and active scalar (density) fields and their derivatives, spectra, and the properties of constant density surfaces. The comparisons between the algorithms are given in terms of performance, accuracy, and compression properties. The results should provide useful information for multi-resolution analysis of turbulence, coherent feature extraction, compression for large datasets handling, as well as simulations algorithms based on multi-resolution methods. In conclusion, the final section provides recommendations for best decomposition algorithms based on several metrics related to computational efficiency and preservation of turbulence properties using a reduced set of coefficients.

  19. A Comparison between Survey and Verbal Choice Methods of Identifying Potential Reinforcers among Employees

    ERIC Educational Resources Information Center

    Wilder, David A; Therrien, Kelly; Wine, Byron

    2006-01-01

    Two methods of assessing preference for stimuli (i.e., potential reinforcers) were compared for adult administrative assistant employees. During Phase 1, a survey method and a verbal choice method of assessing preference for 6 stimuli were administered. During Phase 2, a coupon system was used to determine which categories of stimuli actually…

  20. A Comparison of Web-Based and Paper-Based Survey Methods: Testing Assumptions of Survey Mode and Response Cost

    ERIC Educational Resources Information Center

    Greenlaw, Corey; Brown-Welty, Sharon

    2009-01-01

    Web-based surveys have become more prevalent in areas such as evaluation, research, and marketing research to name a few. The proliferation of these online surveys raises the question, how do response rates compare with traditional surveys and at what cost? This research explored response rates and costs for Web-based surveys, paper surveys, and…

  1. Ground water contamination

    SciTech Connect

    Not Available

    1991-01-01

    This book covers: Ground water contamination and basic concepts of water law; Federal law governing water contamination and remediation; Ground water flow and contaminant migration; Ground water cleanup under CERCLA; Technical methods of remediation and prevention of contamination; Liability for ground water contamination; State constraints on contamination of ground water; Water quantity versus water quality; Prevention of use of contaminated ground water as an alternative to remediation; Economic considerations in liability for ground water contamination; and Contamination, extraction, and injection issues.

  2. Advanced Grounding Methods in the Presence of Carbon Fibre Reinforced Plastic Structures

    NASA Astrophysics Data System (ADS)

    Leininger, M.; Thurecht, F.; Pfeiffer, E.; Ruddle, A.

    2012-05-01

    Lightweight satellite structures are usually of sandwich type where the core is formed of a honeycomb-like structure made of aluminium foil. The outer facesheets are made of aluminium and serve as a ground reference plane. Carbon fibre reinforced plastic (CFRP), however, is a composite material having an electrical conductivity that is about 2000 times lower than the conductivity of aluminium. Since such a material is not suitable to carry electrical current of high value a network of metal sheets (grounding rails) connects all equipment mounted on the satellite structure. This paper describes an evaluation whether the classical grounding rail system can be replaced by a network of round wires while the high-frequency portion of the current is flowing along the CFRP sheet.

  3. Electrical resistivity imaging (ERI) and ground-penetrating radar (GPR) survey at the Giribaile site (upper Guadalquivir valley; southern Spain)

    NASA Astrophysics Data System (ADS)

    Martínez, J.; Rey, J.; Gutiérrez, L. M.; Novo, A.; Ortiz, A. J.; Alejo, M.; Galdón, J. M.

    2015-12-01

    The Giribaile archaeological site is one of the most important Iberian enclaves of the Alto Guadalquivir (Southern Spain). However, to date, only minimal excavation work has been performed at the site. Evaluation requires a preliminary, non-destructive general analysis to determine high-interest areas. This stage required a geophysical survey. Specifically, a 100 m2 grid was selected, where an initial campaign of nine electrical resistivity imaging (ERI) profiles was performed, where each profile was 111 m in length; these profiles were previously located using a detailed topographical survey. A total of 112 electrodes were used for each profile, spaced at 1 m apart with a Wenner-Schlumberger configuration. Secondly, 201 GPR profiles were created using a 500 MHz antenna. The 100 m long profiles were spaced 0.5 m apart and parallel to one another. The present research analyses the efficiency of each of these geophysical tools in supporting archaeological research. Using these methodologies, the position, morphology, and depth of different buried structures can be determined. 3D interpretation of the geophysical survey in 100 × 100 m grid allowed to differentiate structures square and rectangular, interesting buildings in a semicircle (interpreted as ovens) plus delineate different streets. From the geophysical survey follows the Carthaginian presence inside this ancient Iberian enclave.

  4. Density and location of simulated signs of injury affect efficacy of ground surveys for Asian longhorned beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surveys for the detection and delimitation of the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) currently rely upon visual examination of trees to discover the presence of signs of attack such as oviposition pits and exit holes. Understanding the factors ...

  5. Using mark–recapture distance sampling methods on line transect surveys

    USGS Publications Warehouse

    Burt, Louise M.; Borchers, David L.; Jenkins, Kurt J.; Marques, Tigao A

    2014-01-01

    Synthesis and applications. Mark–recapture DS is a widely used method for estimating animal density and abundance when detection of animals at distance zero is not certain. Two observer configurations and three statistical models are described, and it is important to choose the most appropriate model for the observer configuration and target species in question. By way of making the methods more accessible to practicing ecologists, we describe the key ideas underlying MRDS methods, the sometimes subtle differences between them, and we illustrate these by applying different kinds of MRDS method to surveys of two different target species using different survey configurations.

  6. A comparison between protein crystals grown with vapor diffusion methods in microgravity and protein crystals using a gel liquid-liquid diffusion ground-based method

    NASA Technical Reports Server (NTRS)

    Miller, Teresa Y.; He, Xiao-Min; Carter, Daniel C.

    1992-01-01

    Crystals of human serum albumin have been successfully grown in a variety of gels using crystallization conditions otherwise equivalent to those utilized in the popular hanging-drop vapor-equilibrium method. Preliminary comparisons of gel grown crystals with crystals grown by the vapor diffusion method via both ground-based and microgravity methods indicate that crystals superior in size and quality may be grown by limiting solutal convection. Preliminary X-ray diffraction statistics are presented.

  7. The high resolution topographic evolution of an active retrogressive thaw slump compiled from a decade of photography, ground surveys, laser scans and satellite imagery

    NASA Astrophysics Data System (ADS)

    Crosby, B. T.; Barnhart, T. B.; Rowland, J. C.

    2015-12-01

    Remote sensing imagery has enables the temporal reconstruction of thermal erosion features including lakes, shorelines and hillslope failures in remote Arctic locations, yet these planar data limit analysis to lines and areas. This study explores the application of varying techniques to reconstruct the three dimensional evolution of a single thermal erosion feature using a mixture of opportunistic oblique photos, ground surveys and satellite imagery. At the Selawik River retrogressive thaw slump in northwest Alaska, a bush plane collected oblique aerial photos when the feature was first discovered in 2004 and in subsequent years. These images were recently processed via Structure from Motion to generate georeferenced point clouds for the years prior to the initiation of our research. High resolution ground surveys in 2007, 2009 and 2010 were completed using robotic total station. Terrestrial laser scans (TLS) were collected in the summers of 2011 and 2012. Analysis of stereo satellite imagery from 2012 and 2015 enable continued monitoring of the feature after ground campaigns ended. As accurate coregistraion between point clouds is vital to topographic change detection, all prior and subsequent datasets were georeferenced to stable features observed in the 2012 TLS scan. Though this coregistration introduces uncertainty into each image, the magnitudes of uncertainty are significantly smaller than the topographic changes detected. Upslope retreat of the slump headwall generally decreases over time as the slump floor progresses from a highly dissected gully topography to a low relief, earthflow dominated depositional plane. The decreasing slope of the slump floor diminishes transport capacity, resulting in the progressive burial of the slump headwall, thus decreasing headwall retreat rates. This self-regulation of slump size based on feature relief and transport capacity suggests a capacity to predict the maximum size a given feature can expand to before

  8. MODFLOW-2000, the U.S. Geological Survey modular ground-water model : user guide to the LMT6 package, the linkage with MT3DMS for multi-species mass transport modeling

    USGS Publications Warehouse

    Zheng, Chunmiao; Hill, Mary Catherine; Hsieh, Paul A.

    2001-01-01

    MODFLOW-2000, the newest version of MODFLOW, is a computer program that numerically solves the three-dimensional ground-water flow equation for a porous medium using a finite-difference method. MT3DMS, the successor to MT3D, is a computer program for modeling multi-species solute transport in three-dimensional ground-water systems using multiple solution techniques, including the finite-difference method, the method of characteristics (MOC), and the total-variation-diminishing (TVD) method. This report documents a new version of the Link-MT3DMS Package, which enables MODFLOW-2000 to produce the information needed by MT3DMS, and also discusses new visualization software for MT3DMS. Unlike the Link-MT3D Packages that coordinated previous versions of MODFLOW and MT3D, the new Link-MT3DMS Package requires an input file that, among other things, provides enhanced support for additional MODFLOW sink/source packages and allows list-directed (free) format for the flow model produced flow-transport link file. The report contains four parts: (a) documentation of the Link-MT3DMS Package Version 6 for MODFLOW-2000; (b) discussion of several issues related to simulation setup and input data preparation for running MT3DMS with MODFLOW-2000; (c) description of two test example problems, with comparison to results obtained using another MODFLOW-based transport program; and (d) overview of post-simulation visualization and animation using the U.S. Geological Survey?s Model Viewer.

  9. [Essential procedure and key methods for survey of traditional knowledge related to Chinese materia medica resources].

    PubMed

    Cheng, Gong; Huang, Lu-qi; Xue, Da-yuan; Zhang, Xiao-bo

    2014-12-01

    The survey of traditional knowledge related to Chinese materia medica resources is the important component and one of the innovative aspects of the fourth national survey of the Chinese materia medica resources. China has rich traditional knowledge of traditional Chinese medicine (TCM) and the comprehensive investigation of TCM traditional knowledge aims to promote conservation and sustainable use of Chinese materia medica resources. Building upon the field work of pilot investigations, this paper introduces the essential procedures and key methods for conducting the survey of traditional knowledge related to Chinese materia medica resources. The essential procedures are as follows. First is the preparation phrase. It is important to review all relevant literature and provide training to the survey teams so that they have clear understanding of the concept of traditional knowledge and master key survey methods. Second is the field investigation phrase. When conducting field investigations, survey teams should identify the traditional knowledge holders by using the 'snowball method', record the traditional knowledge after obtaining prior informed concerned from the traditional knowledge holders. Researchers should fill out the survey forms provided by the Technical Specification of the Fourth National Survey of Chinese Materia Medica Resources. Researchers should pay particular attention to the scope of traditional knowledge and the method of inheriting the knowledge, which are the key information for traditional knowledge holders and potential users to reach mutual agreed terms to achieve benefit sharing. Third is the data compilation and analysis phrase. Researchers should try to compile and edit the TCM traditional knowledge in accordance with intellectual property rights requirements so that the information collected through the national survey can serve as the basic data for the TCM traditional knowledge database. The key methods of the survey include regional

  10. Ground deformation associated with post-mining activity at the French-German border revealed by novel InSAR time series method

    NASA Astrophysics Data System (ADS)

    Samsonov, Sergey; d'Oreye, Nicolas; Smets, Benoît

    2013-08-01

    We present a novel methodology for integration of multiple InSAR data sets for computation of two dimensional time series of ground deformation. The proposed approach allows combination of SAR data acquired with different acquisition parameters, temporal and spatial sampling and resolution, wavelength and polarization. Produced time series have combined coverage, improved temporal resolution and lower noise level. We apply this methodology for mapping coal mining related ground subsidence and uplift in the Greater Region of Luxembourg along the French-German border. For this we processed 167 Synthetic Aperture Radar ERS-1/2 and ENVISAT images acquired between 1995 and 2009 from one ascending (track 29) and one descending (track 337) tracks and created over five hundred interferograms that were used for time series analysis. Derived vertical and east-west linear deformation rates show with remarkable precision a region of localized ground deformation located above and caused by mining and post-mining activities. Time series of ground deformation display temporal variability: reversal from subsidence to uplift and acceleration of subsidence in the vertical component, and horizontal motion toward the center of the subsidence on the east-west component. InSAR results are validated by leveling measurements collected by the French Geological Survey (BRGM) during 2006-2008. We determined that deformation rate changes are mainly caused by water level variations in the mines. Due to higher temporal and spatial resolution the proposed space-borne method detected a larger number of subsidence and uplift areas in comparison to leveling measurements restricted to annual monitoring of benchmark points along roads. We also identified one deformation region that is not precisely located above the mining sites. Comparison of InSAR measurements with the water levels measured in the mining pits suggest that part of the water that filled the galleries after termination of the

  11. A survey about methods dedicated to epistasis detection.

    PubMed

    Niel, Clément; Sinoquet, Christine; Dina, Christian; Rocheleau, Ghislain

    2015-01-01

    During the past decade, findings of genome-wide association studies (GWAS) improved our knowledge and understanding of disease genetics. To date, thousands of SNPs have been associated with diseases and other complex traits. Statistical analysis typically looks for association between a phenotype and a SNP taken individually via single-locus tests. However, geneticists admit this is an oversimplified approach to tackle the complexity of underlying biological mechanisms. Interaction between SNPs, namely epistasis, must be considered. Unfortunately, epistasis detection gives rise to analytic challenges since analyzing every SNP combination is at present impractical at a genome-wide scale. In this review, we will present the main strategies recently proposed to detect epistatic interactions, along with their operating principle. Some of these methods are exhaustive, such as multifactor dimensionality reduction, likelihood ratio-based tests or receiver operating characteristic curve analysis; some are non-exhaustive, such as machine learning techniques (random forests, Bayesian networks) or combinatorial optimization approaches (ant colony optimization, computational evolution system). PMID:26442103

  12. A survey about methods dedicated to epistasis detection

    PubMed Central

    Niel, Clément; Sinoquet, Christine; Dina, Christian; Rocheleau, Ghislain

    2015-01-01

    During the past decade, findings of genome-wide association studies (GWAS) improved our knowledge and understanding of disease genetics. To date, thousands of SNPs have been associated with diseases and other complex traits. Statistical analysis typically looks for association between a phenotype and a SNP taken individually via single-locus tests. However, geneticists admit this is an oversimplified approach to tackle the complexity of underlying biological mechanisms. Interaction between SNPs, namely epistasis, must be considered. Unfortunately, epistasis detection gives rise to analytic challenges since analyzing every SNP combination is at present impractical at a genome-wide scale. In this review, we will present the main strategies recently proposed to detect epistatic interactions, along with their operating principle. Some of these methods are exhaustive, such as multifactor dimensionality reduction, likelihood ratio-based tests or receiver operating characteristic curve analysis; some are non-exhaustive, such as machine learning techniques (random forests, Bayesian networks) or combinatorial optimization approaches (ant colony optimization, computational evolution system). PMID:26442103

  13. A Simple Method for Measuring Ground-Level Ozone in the Atmosphere

    ERIC Educational Resources Information Center

    Seeley, John V.; Seeley, Stacy K.; Bull, Arthur W.; Fehir, Richard J., Jr.; Cornwall, Susan; Knudsen, Gabriel A.

    2005-01-01

    An iodometric assay that allows the ground-level ozone concentration to be determined with an inexpensive sampling apparatus and a homemade photometer is described. This laboratory experiment applies a variety of different fundamental concepts including oxidation-reduction chemistry, the ideal gas law, and spectroscopic analysis and also provides…

  14. One Landslide forecasting method using ground ruptures model and strong seismic records

    NASA Astrophysics Data System (ADS)

    Tang, Aiping; Cui, Yuping

    2010-05-01

    According to the assessment report of Taiwan earthquake (Ms.7.1 Sep. 21.1999) and Wenchuan earthquake (Ms.8.0, May 21.2008), there were vast ground rupture and strong ground motion to be observed in the above two events, and a great number of a landslides had also been found over a broad area,which damaged and destroyed homes and other structures, blocked roads, disrupted pipelines, and caused other serious damage like barrier lakes. So, it is very important to analysis the distribution and characteristics of landslides under earthquake dynamic loads and forecast what areas may be susceptible to landsliding in future earthquakes. Landslide disaster characteristics including frequency, distribution, and geometries etc in Taiwan and Wenchuan earthquake are summarized at first, and then the correlation between landslide spatial distribution and ground rupture, and strong earthquake motion are explored by using of statistics analysis respectively. Lastly, a landslide disaster forecasting model is built up. The model includes viscoplastic behaviors of soil and rock under seismic dynamic load, and takes into account directly the landslide spatial distribution related to earthquake intensity and ground rupture through a statistical model. A Prediction was made and compared to the results in Wenchuan earthquake.

  15. Methods for gully characterization in agricultural croplands using ground-based light detection and ranging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gullies constitute an important source of sediment from agricultural fields. In order to properly understand gully formation and evolution over time, as well as, sediment yield, detailed topographic representations of agricultural fields are required. New technologies such as ground-based Light Dete...

  16. Application of nonlinear-regression methods to a ground-water flow model of the Albuquerque Basin, New Mexico

    USGS Publications Warehouse

    Tiedeman, C.R.; Kernodle, J.M.; McAda, D.P.

    1998-01-01

    This report documents the application of nonlinear-regression methods to a numerical model of ground-water flow in the Albuquerque Basin, New Mexico. In the Albuquerque Basin, ground water is the primary source for most water uses. Ground-water withdrawal has steadily increased since the 1940's, resulting in large declines in water levels in the Albuquerque area. A ground-water flow model was developed in 1994 and revised and updated in 1995 for the purpose of managing basin ground- water resources. In the work presented here, nonlinear-regression methods were applied to a modified version of the previous flow model. Goals of this work were to use regression methods to calibrate the model with each of six different configurations of the basin subsurface and to assess and compare optimal parameter estimates, model fit, and model error among the resulting calibrations. The Albuquerque Basin is one in a series of north trending structural basins within the Rio Grande Rift, a region of Cenozoic crustal extension. Mountains, uplifts, and fault zones bound the basin, and rock units within the basin include pre-Santa Fe Group deposits, Tertiary Santa Fe Group basin fill, and post-Santa Fe Group volcanics and sediments. The Santa Fe Group is greater than 14,000 feet (ft) thick in the central part of the basin. During deposition of the Santa Fe Group, crustal extension resulted in development of north trending normal faults with vertical displacements of as much as 30,000 ft. Ground-water flow in the Albuquerque Basin occurs primarily in the Santa Fe Group and post-Santa Fe Group deposits. Water flows between the ground-water system and surface-water bodies in the inner valley of the basin, where the Rio Grande, a network of interconnected canals and drains, and Cochiti Reservoir are located. Recharge to the ground-water flow system occurs as infiltration of precipitation along mountain fronts and infiltration of stream water along tributaries to the Rio Grande; subsurface

  17. Comparison of practical vertical ground heat exchanger sizing methods to a Fort Polk data/model benchmark

    SciTech Connect

    Thornton, J.W.; McDowell, T.P.; Hughes, P.J.

    1997-09-01

    The results of five practical vertical ground heat exchanger sizing programs are compared against a detailed simulation model that has been calibrated to monitored data taken from one military family housing unit at Fort Polk, Louisiana. The calibration of the detailed model to data is described in a companion paper. The assertion that the data/detailed model is a useful benchmark for practical sizing methods is based on this calibration. The results from the comparisons demonstrate the current level of agreement between vertical ground heat exchanger sizing methods in common use. It is recommended that the calibration and comparison exercise be repeated with data sets from additional sites in order to build confidence in the practical sizing methods.

  18. A Field Test of Electromigration as a Method for Remediating Sulfate from Shallow Ground Water

    USGS Publications Warehouse

    Patterson, C.G.; Runnells, D.D.

    1996-01-01

    Electromigration offers a potential tool for remediating ground water contaminated with highly soluble components, such as Na+, Cl-, NO3-, and SO4-. A field experiment was designed to test the efficacy of electromigration for preconcentrating dissolved SO42- in ground water associated with a fossil-fuel power plant. Two shallow wells, 25 feet apart (one 25 feet deep, the other 47 feet deep), were constructed in the upper portion of an unconfined alluvial aquifer. The wells were constructed with a double-wall design, with an outer casing of 4-inch PVC and an inner tube of 2-inch PVC; both were fully slotted (0.01 inch). Electrodes were constructed by wrapping the inner tubing with a 100-foot length of rare-earth metal oxide/copper wire. An electrical potential of 10.65 volts DC was applied, and tests were run for periods of 12, 44, and 216 hours. Results showed large changes in the pH from the initial pH of ground water of about 7.5 to values of approximately 2 and 12 at the anode and cathode, respectively. Despite the fact that the test conditions were far from ideal, dissolved SO42- was significantly concentrated at the anode. Over a period of approximately nine days, the concentration of SO42- at the anode reached what appeared to be a steady-state value of 2200 mg/L, compared to the initial value in ground water of approximately 1150 mg/L. The results of this field test should encourage further investigation of electromigration as a tool in the remediation of contaminated ground water.

  19. Survey of sodium removal methods: LMFBR conceptual design study, Phase 3

    SciTech Connect

    1981-09-01

    At the project design review of the nuclear island maintenance on May 5, 1981, DOE requested a survey of current sodium cleaning methods and facilities. Stone & Webster provided a plan and schedule for providing this survey. This plan was approved by Boeing Engineering and Construction Company. The purpose of this survey is to document the sodium removal technology and experience as it relates to the CDS Large Developmental Plant, summarize the information, and provide a prospective for the CDS project. The recommendations generated are intended to provide input for a design and layout review of the Nuclear Island Maintenance Building (NIMB).

  20. Conditional pseudolikelihood methods for clustered ordinal, multinomial, or count outcomes with complex survey data.

    PubMed

    Brumback, Babette A; Cai, Zhuangyu; He, Zhulin; Zheng, Hao W; Dailey, Amy B

    2013-04-15

    In order to adjust individual-level covariate effects for confounding due to unmeasured neighborhood characteristics, we have recently developed conditional pseudolikelihood methods to estimate the parameters of a proportional odds model for clustered ordinal outcomes with complex survey data. The methods require sampling design joint probabilities for each within-neighborhood pair. In the present article, we develop a similar methodology for a baseline category logit model for clustered multinomial outcomes and for a loglinear model for clustered count outcomes. All of the estimators and asymptotic sampling distributions we present can be conveniently computed using standard logistic regression software for complex survey data, such as sas proc surveylogistic. We demonstrate validity of the methods theoretically and also empirically by using simulations. We apply the new method for clustered multinomial outcomes to data from the 2008 Florida Behavioral Risk Factor Surveillance System survey in order to investigate disparities in frequency of dental cleaning both unadjusted and adjusted for confounding by neighborhood. PMID:22976045

  1. Indigo snake capture methods: effectiveness of two survey techniques for Drymarchon couperi in Georgia

    USGS Publications Warehouse

    Hyslop, N.L.; Meyers, J.M.; Cooper, R.J.; Stevenson, J.

    2009-01-01

    Drymarchon couperi (Eastern Indigo Snake), a federally threatened species of the southeastern Coastal Plain, has presented challenges for surveyors, with few reliable methods developed for its detection or monitoring. Surveys for D. couperi at potential underground shelters conducted in late fall through early spring have been relatively successful when conducted by experienced surveyors, especially in the northern portions of the range. However, trapping efforts for D. couperi conducted throughout the range have met with limited success. To further evaluate detection methods, we conducted trapping and surveying from December 2002 to April 2004 in areas known to support D. couperi in southeastern Georgia. We captured 18 D. couperi through surveys of potential underground shelters from December 2002 to March 2003 (14 person-hours per capture) and six individuals through trapping (141 trap days or 27 in-field person-hours per capture). Trapping was most successful during early fall, a period when surveys are often less effective compared to those conducted in late fall through early spring. We recommend a combination of surveys from mid-fall through March in conjunction with trapping, especially from late-summer through fall in the northern portions of the snake?s range. We also recommend further experimentation with alternative trap designs and survey methods for D. couperi.

  2. Comparative analysis of different survey methods for monitoring fish assemblages in coastal habitats.

    PubMed

    Baker, Duncan G L; Eddy, Tyler D; McIver, Reba; Schmidt, Allison L; Thériault, Marie-Hélène; Boudreau, Monica; Courtenay, Simon C; Lotze, Heike K

    2016-01-01

    Coastal ecosystems are among the most productive yet increasingly threatened marine ecosystems worldwide. Particularly vegetated habitats, such as eelgrass (Zostera marina) beds, play important roles in providing key spawning, nursery and foraging habitats for a wide range of fauna. To properly assess changes in coastal ecosystems and manage these critical habitats, it is essential to develop sound monitoring programs for foundation species and associated assemblages. Several survey methods exist, thus understanding how different methods perform is important for survey selection. We compared two common methods for surveying macrofaunal assemblages: beach seine netting and underwater visual census (UVC). We also tested whether assemblages in shallow nearshore habitats commonly sampled by beach seines are similar to those of nearby eelgrass beds often sampled by UVC. Among five estuaries along the Southern Gulf of St. Lawrence, Canada, our results suggest that the two survey methods yield comparable results for species richness, diversity and evenness, yet beach seines yield significantly higher abundance and different species composition. However, sampling nearshore assemblages does not represent those in eelgrass beds despite considerable overlap and close proximity. These results have important implications for how and where macrofaunal assemblages are monitored in coastal ecosystems. Ideally, multiple survey methods and locations should be combined to complement each other in assessing the entire assemblage and full range of changes in coastal ecosystems, thereby better informing coastal zone management. PMID:27018396

  3. Comparative analysis of different survey methods for monitoring fish assemblages in coastal habitats

    PubMed Central

    Baker, Duncan G.L.; McIver, Reba; Schmidt, Allison L.; Thériault, Marie-Hélène; Boudreau, Monica; Courtenay, Simon C.; Lotze, Heike K.

    2016-01-01

    Coastal ecosystems are among the most productive yet increasingly threatened marine ecosystems worldwide. Particularly vegetated habitats, such as eelgrass (Zostera marina) beds, play important roles in providing key spawning, nursery and foraging habitats for a wide range of fauna. To properly assess changes in coastal ecosystems and manage these critical habitats, it is essential to develop sound monitoring programs for foundation species and associated assemblages. Several survey methods exist, thus understanding how different methods perform is important for survey selection. We compared two common methods for surveying macrofaunal assemblages: beach seine netting and underwater visual census (UVC). We also tested whether assemblages in shallow nearshore habitats commonly sampled by beach seines are similar to those of nearby eelgrass beds often sampled by UVC. Among five estuaries along the Southern Gulf of St. Lawrence, Canada, our results suggest that the two survey methods yield comparable results for species richness, diversity and evenness, yet beach seines yield significantly higher abundance and different species composition. However, sampling nearshore assemblages does not represent those in eelgrass beds despite considerable overlap and close proximity. These results have important implications for how and where macrofaunal assemblages are monitored in coastal ecosystems. Ideally, multiple survey methods and locations should be combined to complement each other in assessing the entire assemblage and full range of changes in coastal ecosystems, thereby better informing coastal zone management. PMID:27018396

  4. Informetric Theories and Methods for Exploring the Internet: An Analytical Survey of Recent Research Literature.

    ERIC Educational Resources Information Center

    Bar-Ilan, Judit; Peritz, Bluma C.

    2002-01-01

    Presents a selective review of research based on the Internet, using bibliometric and informetric methods and tools. Highlights include data collection methods on the Internet, including surveys, logging, and search engines; and informetric analysis, including citation analysis and content analysis. (Contains 78 references.) (Author/LRW)

  5. Inclusion of trial functions in the Langevin equation path integral ground state method: Application to parahydrogen clusters and their isotopologues

    NASA Astrophysics Data System (ADS)

    Schmidt, Matthew; Constable, Steve; Ing, Christopher; Roy, Pierre-Nicholas

    2014-06-01

    We developed and studied the implementation of trial wavefunctions in the newly proposed Langevin equation Path Integral Ground State (LePIGS) method [S. Constable, M. Schmidt, C. Ing, T. Zeng, and P.-N. Roy, J. Phys. Chem. A 117, 7461 (2013)]. The LePIGS method is based on the Path Integral Ground State (PIGS) formalism combined with Path Integral Molecular Dynamics sampling using a Langevin equation based sampling of the canonical distribution. This LePIGS method originally incorporated a trivial trial wavefunction, ψT, equal to unity. The present paper assesses the effectiveness of three different trial wavefunctions on three isotopes of hydrogen for cluster sizes N = 4, 8, and 13. The trial wavefunctions of interest are the unity trial wavefunction used in the original LePIGS work, a Jastrow trial wavefunction that includes correlations due to hard-core repulsions, and a normal mode trial wavefunction that includes information on the equilibrium geometry. Based on this analysis, we opt for the Jastrow wavefunction to calculate energetic and structural properties for parahydrogen, orthodeuterium, and paratritium clusters of size N = 4 - 19, 33. Energetic and structural properties are obtained and compared to earlier work based on Monte Carlo PIGS simulations to study the accuracy of the proposed approach. The new results for paratritium clusters will serve as benchmark for future studies. This paper provides a detailed, yet general method for optimizing the necessary parameters required for the study of the ground state of a large variety of systems.

  6. Inclusion of trial functions in the Langevin equation path integral ground state method: Application to parahydrogen clusters and their isotopologues

    SciTech Connect

    Schmidt, Matthew; Constable, Steve; Ing, Christopher; Roy, Pierre-Nicholas

    2014-06-21

    We developed and studied the implementation of trial wavefunctions in the newly proposed Langevin equation Path Integral Ground State (LePIGS) method [S. Constable, M. Schmidt, C. Ing, T. Zeng, and P.-N. Roy, J. Phys. Chem. A 117, 7461 (2013)]. The LePIGS method is based on the Path Integral Ground State (PIGS) formalism combined with Path Integral Molecular Dynamics sampling using a Langevin equation based sampling of the canonical distribution. This LePIGS method originally incorporated a trivial trial wavefunction, ψ{sub T}, equal to unity. The present paper assesses the effectiveness of three different trial wavefunctions on three isotopes of hydrogen for cluster sizes N = 4, 8, and 13. The trial wavefunctions of interest are the unity trial wavefunction used in the original LePIGS work, a Jastrow trial wavefunction that includes correlations due to hard-core repulsions, and a normal mode trial wavefunction that includes information on the equilibrium geometry. Based on this analysis, we opt for the Jastrow wavefunction to calculate energetic and structural properties for parahydrogen, orthodeuterium, and paratritium clusters of size N = 4 − 19, 33. Energetic and structural properties are obtained and compared to earlier work based on Monte Carlo PIGS simulations to study the accuracy of the proposed approach. The new results for paratritium clusters will serve as benchmark for future studies. This paper provides a detailed, yet general method for optimizing the necessary parameters required for the study of the ground state of a large variety of systems.

  7. Methods and Sources of Data Used to Develop Selected Water-Quality Indicators for Streams and Ground Water for EPA's 2007 Report on the Environment: Science Report

    USGS Publications Warehouse

    Baker, Nancy T.; Wilson, John T.; Moran, Michael J.

    2008-01-01

    The U.S. Geological Survey (USGS) was one of numerous governmental agencies, private organizations, and the academic community that provided data and interpretations for the U.S. Environmental Protection Agency?s (USEPA) 2007 Report on the Environment: Science Report. This report documents the sources of data and methods used to develop selected water?quality indicators for the 2007 edition of the report compiled by USEPA. Stream and ground?water?quality data collected nationally in a consistent manner as part of the USGS?s National Water?Quality Assessment Program (NAWQA) were provided for several water?quality indicators, including Nitrogen and Phosphorus in Streams in Agricultural Watersheds; Pesticides in Streams in Agricultural Watersheds; and Nitrate and Pesticides in Shallow Ground Water in Agricultural Watersheds. In addition, the USGS provided nitrate (nitrate plus nitrite) and phosphorus riverine load estimates calculated from water?quality and streamflow data collected as part of its National Stream Water Quality Accounting Network (NASQAN) and its Federal?State Cooperative Program for the Nitrogen and Phosphorus Discharge from Large Rivers indicator.

  8. MODFLOW-2005, the U.S. Geological Survey modular ground-water model - documentation of shared node local grid refinement (LGR) and the boundary flow and head (BFH) package

    USGS Publications Warehouse

    Mehl, Steffen W.; Hill, Mary C.

    2006-01-01

    This report documents the addition of shared node Local Grid Refinement (LGR) to MODFLOW-2005, the U.S. Geological Survey modular, transient, three-dimensional, finite-difference ground-water flow model. LGR provides the capability to simulate ground-water flow using one block-shaped higher-resolution local grid (a child model) within a coarser-grid parent model. LGR accomplishes this by iteratively coupling two separate MODFLOW-2005 models such that heads and fluxes are balanced across the shared interfacing boundary. LGR can be used in two-and three-dimensional, steady-state and transient simulations and for simulations of confined and unconfined ground-water systems. Traditional one-way coupled telescopic mesh refinement (TMR) methods can have large, often undetected, inconsistencies in heads and fluxes across the interface between two model grids. The iteratively coupled shared-node method of LGR provides a more rigorous coupling in which the solution accuracy is controlled by convergence criteria defined by the user. In realistic problems, this can result in substantially more accurate solutions and require an increase in computer processing time. The rigorous coupling enables sensitivity analysis, parameter estimation, and uncertainty analysis that reflects conditions in both model grids. This report describes the method used by LGR, evaluates LGR accuracy and performance for two- and three-dimensional test cases, provides input instructions, and lists selected input and output files for an example problem. It also presents the Boundary Flow and Head (BFH) Package, which allows the child and parent models to be simulated independently using the boundary conditions obtained through the iterative process of LGR.

  9. Google Street View as an alternative method to car surveys in large-scale vegetation assessments.

    PubMed

    Deus, Ernesto; Silva, Joaquim S; Catry, Filipe X; Rocha, Miguel; Moreira, Francisco

    2015-10-01

    Car surveys (CS) are a common method for assessing the distribution of alien invasive plants. Google Street View (GSV), a free-access web technology where users may experience a virtual travel along roads, has been suggested as a cost-effective alternative to car surveys. We tested if we could replicate the results from a countrywide survey conducted by car in Portugal using GSV as a remote sensing tool, aiming at assessing the distribution of Eucalyptus globulus Labill. wildlings on roadsides adjacent to eucalypt stands. Georeferenced points gathered along CS were used to create road transects visible as lines overlapping the road in GSV environment, allowing surveying the same sampling areas using both methods. This paper presents the results of the comparison between the two methods. Both methods produced similar models of plant abundance, selecting the same explanatory variables, in the same hierarchical order of importance and depicting a similar influence on plant abundance. Even though the GSV model had a lower performance and the GSV survey detected fewer plants, additional variables collected exclusively with GSV improved model performance and provided a new insight into additional factors influencing plant abundance. The survey using GSV required ca. 9 % of the funds and 62 % of the time needed to accomplish the CS. We conclude that GSV may be a cost-effective alternative to CS. We discuss some advantages and limitations of GSV as a survey method. We forecast that GSV may become a widespread tool in road ecology, particularly in large-scale vegetation assessments. PMID:27624742

  10. An UAV scheduling and planning method for post-disaster survey

    NASA Astrophysics Data System (ADS)

    Li, G. Q.; Zhou, X. G.; Yin, J.; Xiao, Q. Y.

    2014-11-01

    Annually, the extreme climate and special geological environments lead to frequent natural disasters, e.g., earthquakes, floods, etc. The disasters often bring serious casualties and enormous economic losses. Post-disaster surveying is very important for disaster relief and assessment. As the Unmanned Aerial Vehicle (UAV) remote sensing with the advantage of high efficiency, high precision, high flexibility, and low cost, it is widely used in emergency surveying in recent years. As the UAVs used in emergency surveying cannot stop and wait for the happening of the disaster, when the disaster happens the UAVs usually are working at everywhere. In order to improve the emergency surveying efficiency, it is needed to track the UAVs and assign the emergency surveying task for each selected UAV. Therefore, a UAV tracking and scheduling method for post-disaster survey is presented in this paper. In this method, Global Positioning System (GPS), and GSM network are used to track the UAVs; an emergency tracking UAV information database is built in advance by registration, the database at least includes the following information, e.g., the ID of the UAVs, the communication number of the UAVs; when catastrophe happens, the real time location of all UAVs in the database will be gotten using emergency tracking method at first, then the traffic cost time for all UAVs to the disaster region will be calculated based on the UAVs' the real time location and the road network using the nearest services analysis algorithm; the disaster region is subdivided to several emergency surveying regions based on DEM, area, and the population distribution map; the emergency surveying regions are assigned to the appropriated UAV according to shortest cost time rule. The UAVs tracking and scheduling prototype is implemented using SQLServer2008, ArcEnginge 10.1 SDK, Visual Studio 2010 C#, Android, SMS Modem, and Google Maps API.

  11. 3D Monitoring under the Keciova Mosque (Casbah-Algier, Algeria) with Ground Penetrating Radar Method

    NASA Astrophysics Data System (ADS)

    Kadioglu, Selma; Kagan Kadioglu, Yusuf; Deniz, Kiymet; Akin Akyol, Ali

    2014-05-01

    Keciova (Ketchaoua) Mosque, in Casbah-Algiers, the capital of Algeria, is a UNESCO World Heritage Site. Keciova Mosque was originally built in 1612 by the Ottoman Empire. A RAMAC CU II GPR system and a 250 MHz shielded antenna have been employed inside of the Mosque including the Cathedral and inside of the burial chambers under the Cathedral Site on parallel profiles spaced approximately 0.30 m apart to measure data. After applying standard two-dimensional (2D) and three dimensional (3D) imaging techniques, transparent 3D imaging techniques have been used to photograph the foundational infrastructures, buried remains and safety problems of the Mosque. The results showed that we obtained 3D GPR visualization until 12.0 m in depth. Firstly we imaged the base floor including corridors. Then we monitored buried remains under the first ground level between 5.0-7.0 m in depths. Finally we indicated 3D GPR photographs a spectacular protected buried old mosque structures under the second ground level between 9.0-12.0 m in depths. This project has been supported by Republic of Turkey Prime Ministry Turkish Cooperation and Coordination Agency (TIKA). This study is a contribution to the EU funded COST action TU1208, "Civil Engineering Applications of Ground penetrating Radar".

  12. Ground motion simulations in Marmara (Turkey) region from 3D finite difference method

    NASA Astrophysics Data System (ADS)

    Aochi, Hideo; Ulrich, Thomas; Douglas, John

    2016-04-01

    In the framework of the European project MARSite (2012-2016), one of the main contributions from our research team was to provide ground-motion simulations for the Marmara region from various earthquake source scenarios. We adopted a 3D finite difference code, taking into account the 3D structure around the Sea of Marmara (including the bathymetry) and the sea layer. We simulated two moderate earthquakes (about Mw4.5) and found that the 3D structure improves significantly the waveforms compared to the 1D layer model. Simulations were carried out for different earthquakes (moderate point sources and large finite sources) in order to provide shake maps (Aochi and Ulrich, BSSA, 2015), to study the variability of ground-motion parameters (Douglas & Aochi, BSSA, 2016) as well as to provide synthetic seismograms for the blind inversion tests (Diao et al., GJI, 2016). The results are also planned to be integrated in broadband ground-motion simulations, tsunamis generation and simulations of triggered landslides (in progress by different partners). The simulations are freely shared among the partners via the internet and the visualization of the results is diffused on the project's homepage. All these simulations should be seen as a reference for this region, as they are based on the latest knowledge that obtained during the MARSite project, although their refinement and validation of the model parameters and the simulations are a continuing research task relying on continuing observations. The numerical code used, the models and the simulations are available on demand.

  13. A Method for Calculating the Probability of Successfully Completing a Rocket Propulsion Ground Test

    NASA Technical Reports Server (NTRS)

    Messer, Bradley

    2007-01-01

    Propulsion ground test facilities face the daily challenge of scheduling multiple customers into limited facility space and successfully completing their propulsion test projects. Over the last decade NASA s propulsion test facilities have performed hundreds of tests, collected thousands of seconds of test data, and exceeded the capabilities of numerous test facility and test article components. A logistic regression mathematical modeling technique has been developed to predict the probability of successfully completing a rocket propulsion test. A logistic regression model is a mathematical modeling approach that can be used to describe the relationship of several independent predictor variables X(sub 1), X(sub 2),.., X(sub k) to a binary or dichotomous dependent variable Y, where Y can only be one of two possible outcomes, in this case Success or Failure of accomplishing a full duration test. The use of logistic regression modeling is not new; however, modeling propulsion ground test facilities using logistic regression is both a new and unique application of the statistical technique. Results from this type of model provide project managers with insight and confidence into the effectiveness of rocket propulsion ground testing.

  14. Surface Signature Characterization at SPE through Ground-Proximal Methods: Methodology Change and Technical Justification

    SciTech Connect

    Schultz-Fellenz, Emily S.

    2015-09-09

    A portion of LANL’s FY15 SPE objectives includes initial ground-based or ground-proximal investigations at the SPE Phase 2 site. The area of interest is the U2ez location in Yucca Flat. This collection serves as a baseline for discrimination of surface features and acquisition of topographic signatures prior to any development or pre-shot activities associated with SPE Phase 2. Our team originally intended to perform our field investigations using previously vetted ground-based (GB) LIDAR methodologies. However, the extended proposed time frame of the GB LIDAR data collection, and associated data processing time and delivery date, were unacceptable. After technical consultation and careful literature research, LANL identified an alternative methodology to achieve our technical objectives and fully support critical model parameterization. Very-low-altitude unmanned aerial systems (UAS) photogrammetry appeared to satisfy our objectives in lieu of GB LIDAR. The SPE Phase 2 baseline collection was used as a test of this UAS photogrammetric methodology.

  15. Gaussian-Basis Monte Carlo Method for Numerical Study on Ground States of Itinerant and Strongly Correlated Electron Systems

    NASA Astrophysics Data System (ADS)

    Aimi, Takeshi; Imada, Masatoshi

    2007-08-01

    We examine Gaussian-basis Monte Carlo (GBMC) method introduced by Corney and Drummond. This method is based on an expansion of the density-matrix operator \\hatρ by means of the coherent Gaussian-type operator basis \\hatΛ and does not suffer from the minus sign problem. The original method, however, often fails in reproducing the true ground state and causes systematic errors of calculated physical quantities because the samples are often trapped in some metastable or symmetry broken states. To overcome this difficulty, we combine the quantum-number projection scheme proposed by Assaad, Werner, Corboz, Gull, and Troyer in conjunction with the importance sampling of the original GBMC method. This improvement allows us to carry out the importance sampling in the quantum-number-projected phase-space. Some comparisons with the previous quantum-number projection scheme indicate that, in our method, the convergence with the ground state is accelerated, which makes it possible to extend the applicability and widen the range of tractable parameters in the GBMC method. The present scheme offers an efficient practical way of computation for strongly correlated electron systems beyond the range of system sizes, interaction strengths and lattice structures tractable by other computational methods such as the quantum Monte Carlo method.

  16. A Preliminary Survey of Benthos from the Nephrops norvegicusMud Grounds in the North-western Irish Sea

    NASA Astrophysics Data System (ADS)

    Hensley, R. T.

    1996-04-01

    A preliminary survey of benthic infauna from an extensive basin of soft mud in the Irish Sea was carried out in 1992. A total of 110 taxa were recorded of which polychaete worms (Phylum Annelida) constituted 77·8% of all taxa recorded. Hierarchical classification and detrended correspondence analysis divided the area studied into five regions which could be correlated to the differences in superficial sediments and depth across the basin. Although much of the fauna was ubiquitous, a change in trophic structure was observed, with tubiculous polychaetes becoming progressively less common in deeper softer sediment areas where surface and non-selective deposit-feeding taxa predominated.

  17. Theoretical grounds of relativistic methods for calculation of spin–spin coupling constants in nuclear magnetic resonance spectra

    NASA Astrophysics Data System (ADS)

    Rusakova, I. L.; Rusakov, Yu Yu; Krivdin, L. B.

    2016-04-01

    The theoretical grounds of the modern relativistic methods for quantum chemical calculation of spin–spin coupling constants in nuclear magnetic resonance spectra are considered. Examples and prospects of application of relativistic calculations of these constants in the structural studies of organic and heteroorganic compounds are discussed. Practical recommendations on relativistic calculations of spin–spin coupling constants using the available software are given. The bibliography includes 622 references.

  18. Detection of contaminant plumes in ground water of Long Island, New York, by electromagnetic terrain-conductivity surveys

    USGS Publications Warehouse

    Mack, Thomas J.; Maus, P.E.

    1986-01-01

    Electromagnetic terrain conductivity surveys were conducted at four landfills in Suffolk county and at an artificial recharge site in Nassau County to assess the feasibility of this technique for detecting contaminant plumes. The technique was successful at three of the landfills; results compared closely with those indicated by specific conductance of water from observation wells on the sites. Data from the three sites for which the technique was successful--the Horseblock Road landfill , the Manorville scavenger waste disposal facility, and the Riverhead landfill--revealed pronounced terrain conductivity anomalies that reflect known contaminant plumes. Plumes at the other two sites--Blydenburgh landfill and the East Meadow artificial recharge site--could not be detected because cultural interferences were too great and, at the Blydenburgh site, depth to water was too great. The interferences included pipelines, utility cables, and traffic. Given favorable conditions, such as high plume conductivity, lack of cultural interferences, and a depth of less than 100 ft to the plume, electromagnetic surveying can provide a rapid means of locating contaminant plumes. (Author 's abstract)

  19. A multireference perturbation method using non-orthogonal Hartree-Fock determinants for ground and excited states

    SciTech Connect

    Yost, Shane R.; Kowalczyk, Tim; Van Voorhis, Troy

    2013-11-07

    In this article we propose the ΔSCF(2) framework, a multireference strategy based on second-order perturbation theory, for ground and excited electronic states. Unlike the complete active space family of methods, ΔSCF(2) employs a set of self-consistent Hartree-Fock determinants, also known as ΔSCF states. Each ΔSCF electronic state is modified by a first-order correction from Møller-Plesset perturbation theory and used to construct a Hamiltonian in a configuration interactions like framework. We present formulas for the resulting matrix elements between nonorthogonal states that scale as N{sub occ}{sup 2}N{sub virt}{sup 3}. Unlike most active space methods, ΔSCF(2) treats the ground and excited state determinants even-handedly. We apply ΔSCF(2) to the H{sub 2}, hydrogen fluoride, and H{sub 4} systems and show that the method provides accurate descriptions of ground- and excited-state potential energy surfaces with no single active space containing more than 10 ΔSCF states.

  20. A multireference perturbation method using non-orthogonal Hartree-Fock determinants for ground and excited states.

    PubMed

    Yost, Shane R; Kowalczyk, Tim; Van Voorhis, Troy

    2013-11-01

    In this article we propose the ΔSCF(2) framework, a multireference strategy based on second-order perturbation theory, for ground and excited electronic states. Unlike the complete active space family of methods, ΔSCF(2) employs a set of self-consistent Hartree-Fock determinants, also known as ΔSCF states. Each ΔSCF electronic state is modified by a first-order correction from Mo̸ller-Plesset perturbation theory and used to construct a Hamiltonian in a configuration interactions like framework. We present formulas for the resulting matrix elements between nonorthogonal states that scale as N(occ)(2)N(virt)(3). Unlike most active space methods, ΔSCF(2) treats the ground and excited state determinants even-handedly. We apply ΔSCF(2) to the H2, hydrogen fluoride, and H4 systems and show that the method provides accurate descriptions of ground- and excited-state potential energy surfaces with no single active space containing more than 10 ΔSCF states. PMID:24206284

  1. A data input program (MFI2K) for the U.S. Geological Survey modular ground-water model (MODFLOW-2000)

    USGS Publications Warehouse

    Harbaugh, Arlen W.

    2002-01-01

    MFI2K is a data-input (entry) program for the U.S. Geological Survey modular three-dimensional finite-difference ground-water model, MODFLOW-2000. MFI2K runs on personal computers. MFI2K supports the solute transport and parameter-estimation capabilities that are incorporated in MODFLOW-2000. Data for MODPATH, a particle-tracking program for use with MODFLOW-2000, also can be entered using MFI2K. MFI2K is designed to be easy to use; data are entered interactively through a series of display screens. MFI2K also can be used in conjunction with other data-input programs so that the different parts of a model dataset can be entered using the most suitable program. MFI2K interfaces to an external program for entering or editing two-dimensional arrays and lists of stress data. This report provides instructions for using MFI2K.

  2. Microgravimetric and ground penetrating radar geophysical methods to map the shallow karstic cavities network in a coastal area (Marina Di Capilungo, Lecce, Italy)

    NASA Astrophysics Data System (ADS)

    Leucci, Giovanni; De Giorgi, Lara

    2010-06-01

    The coastal area Marina di Capilungo located ~50km south-west of Lecce (Italy) is one of the sites at greatest geological risk in the Salento peninsula. In the past few decades, Marina di Capilungo has been affected by a series of subsidence events, which have led in some cases to the partial collapse of buildings and road surfaces. These events had both social repercussions, causing alarm and emergency situations, and economic ones in terms of the funds for restoration. With the aim of mapping the subsurface karstic features, and so to assess the dimensions of the phenomena in order to prevent and/or limit the ground subsidence events, integrated geophysical surveys were undertaken in an area of ~70000m2 at Marina di Capilungo. Large volume voids such as karstic cavities are excellent targets for microgravity surveys. The absent mass of the void creates a quantifiable disturbance in the earth's gravitational field, with the magnitude of the disturbance directly proportional to the volume of the void. Smaller shallow voids can be detected using ground-penetrating radar (GPR). Microgravimetric and GPR geophysical methods were therefore used. An accurate interpretation was obtained using small station spacing and accurate geophysical data processing. The interpretation was facilitated by combining the modelling of the data with the geological and topographic information for explored caves. The GPR method can complement the microgravimetric technique in determining cavity depths and in verifying the presence of off-line features and numerous areas of small cavities, which may be difficult to be resolved with only microgravimetric data. However, the microgravimetric can complement GPR in delineating with accuracy the shallow cavities in a wide area where GPR measurements are difficult. Furthermore, microgravity surveys in an urban environment require effective and accurate consideration of the effects given by infrastructures, such as buildings, as well as those given

  3. Hierarchical Methods for the Generation, Publication and Visualization of Huge Astronomical Data Cube Surveys

    NASA Astrophysics Data System (ADS)

    Fernique, P.; Allen, M.; Boch, T.; Bonnarel, F.; Oberto, A.

    2015-09-01

    The CDS has developed and validated new methods to generate, publish and display huge astronomical image data cubes based on the Hierarchical Progressive Survey (HiPS) framework. Data cubes with two spatial dimensions and an additional spectral or temporal dimension can be mapped onto HEALPix grids at different resolutions, which supports zooming and panning of the data across the sky with the ability to explore the third dimension of the cube. These methods are successfully applied to different sorts of cube data, and surveys of cube data.

  4. Compilation of field methods used in geochemical prospecting by the U.S. Geological Survey

    USGS Publications Warehouse

    Lakin, Hubert William; Ward, Frederick Norville; Almond, Hy

    1952-01-01

    The field methods described in this report are those currently used in geochemical prospecting by the U. S. Geological Survey. Some have been published, others are being processed for publication, while others are still being investigated. The purpose in compiling these methods is to make them readily available in convenient form. The methods have not been thoroughly tested and none is wholly satisfactory. Research is being continued.

  5. A comparison of web-based and paper-based survey methods: testing assumptions of survey mode and response cost.

    PubMed

    Greenlaw, Corey; Brown-Welty, Sharon

    2009-10-01

    Web-based surveys have become more prevalent in areas such as evaluation, research, and marketing research to name a few. The proliferation of these online surveys raises the question, how do response rates compare with traditional surveys and at what cost? This research explored response rates and costs for Web-based surveys, paper surveys, and mixed-mode surveys. The participants included evaluators from the American Evaluation Association (AEA). Results included that mixed-mode, while more expensive, had higher response rates. PMID:19605623

  6. A Method for Calculating the Probability of Successfully Completing a Rocket Propulsion Ground Test

    NASA Technical Reports Server (NTRS)

    Messer, Bradley P.

    2004-01-01

    Propulsion ground test facilities face the daily challenges of scheduling multiple customers into limited facility space and successfully completing their propulsion test projects. Due to budgetary and schedule constraints, NASA and industry customers are pushing to test more components, for less money, in a shorter period of time. As these new rocket engine component test programs are undertaken, the lack of technology maturity in the test articles, combined with pushing the test facilities capabilities to their limits, tends to lead to an increase in facility breakdowns and unsuccessful tests. Over the last five years Stennis Space Center's propulsion test facilities have performed hundreds of tests, collected thousands of seconds of test data, and broken numerous test facility and test article parts. While various initiatives have been implemented to provide better propulsion test techniques and improve the quality, reliability, and maintainability of goods and parts used in the propulsion test facilities, unexpected failures during testing still occur quite regularly due to the harsh environment in which the propulsion test facilities operate. Previous attempts at modeling the lifecycle of a propulsion component test project have met with little success. Each of the attempts suffered form incomplete or inconsistent data on which to base the models. By focusing on the actual test phase of the tests project rather than the formulation, design or construction phases of the test project, the quality and quantity of available data increases dramatically. A logistic regression model has been developed form the data collected over the last five years, allowing the probability of successfully completing a rocket propulsion component test to be calculated. A logistic regression model is a mathematical modeling approach that can be used to describe the relationship of several independent predictor variables X(sub 1), X(sub 2),..,X(sub k) to a binary or dichotomous

  7. Modifications of the U.S. Geological Survey modular, finite-difference, ground-water flow model to read and write geographic information system files

    USGS Publications Warehouse

    Orzol, Leonard L.; McGrath, Timothy S.

    1992-01-01

    This report documents modifications to the U.S. Geological Survey modular, three-dimensional, finite-difference, ground-water flow model, commonly called MODFLOW, so that it can read and write files used by a geographic information system (GIS). The modified model program is called MODFLOWARC. Simulation programs such as MODFLOW generally require large amounts of input data and produce large amounts of output data. Viewing data graphically, generating head contours, and creating or editing model data arrays such as hydraulic conductivity are examples of tasks that currently are performed either by the use of independent software packages or by tedious manual editing, manipulating, and transferring data. Programs such as GIS programs are commonly used to facilitate preparation of the model input data and analyze model output data; however, auxiliary programs are frequently required to translate data between programs. Data translations are required when different programs use different data formats. Thus, the user might use GIS techniques to create model input data, run a translation program to convert input data into a format compatible with the ground-water flow model, run the model, run a translation program to convert the model output into the correct format for GIS, and use GIS to display and analyze this output. MODFLOWARC, avoids the two translation steps and transfers data directly to and from the ground-water-flow model. This report documents the design and use of MODFLOWARC and includes instructions for data input/output of the Basic, Block-centered flow, River, Recharge, Well, Drain, Evapotranspiration, General-head boundary, and Streamflow-routing packages. The modification to MODFLOW and the Streamflow-Routing package was minimized. Flow charts and computer-program code describe the modifications to the original computer codes for each of these packages. Appendix A contains a discussion on the operation of MODFLOWARC using a sample problem.

  8. Conduct a state-of-the-art survey of existing knowledge for the design of ground-source heat pumps

    NASA Astrophysics Data System (ADS)

    Ball, D. A.

    1982-03-01

    Horizontal serpentine coils have been and are at present the most common coil configuration. Best design data exist for horizontal coils in heating only applications with moist soil. Applications in dry soil or where significant summer cooling is required are not as well understood at this time. A seasonal performance factor of about 3.0 can be expected for a properly designed and installed residential ground-coupled heat-pump system. Long-term durability of buried steel and cooper tubing has been demonstrated. Life expectancy of thin-walled polyethylene tubing in the heating-only application is expected to be equally as good: however, present experience is limited to less than five years. In the cooling application with heat-rejection temperatures exceeding 100 F, some cracking has been experienced upon subsequent cool-down for heating operation due to localized stresses induced by conformity of the tubing to bedding material (stones) when hot. Receding of the soil from the pipe after a period of several years was experienced in the late 1940's. An understanding of this phenomenon may be crucial to the long-term operating success of these systems.

  9. Single-Event Effects Ground Testing and On-Orbit Rate Prediction Methods: The Past, Present and Future

    NASA Technical Reports Server (NTRS)

    Reed, Robert A.; Kinnison, Jim; Pickel, Jim; Buchner, Stephen; Marshall, Paul W.; Kniffin, Scott; LaBel, Kenneth A.

    2003-01-01

    Over the past 27 years, or so, increased concern over single event effects in spacecraft systems has resulted in research, development and engineering activities centered around a better understanding of the space radiation environment, single event effects predictive methods, ground test protocols, and test facility developments. This research has led to fairly well developed methods for assessing the impact of the space radiation environment on systems that contain SEE sensitive devices and the development of mitigation strategies either at the system or device level.

  10. A thermal profile method to identify potential ground-water discharge areas and preferred salmonid habitats for long river reaches

    USGS Publications Warehouse

    Vaccaro, J.J.; Maloy, K.J.

    2006-01-01

    The thermal regime of riverine systems is a major control on aquatic ecosystems. Ground water discharge is an important abiotic driver of the aquatic ecosystem because it provides preferred thermal structure and habitat for different types of fish at different times in their life history. In large diverse river basins with an extensive riverine system, documenting the thermal regime and ground-water discharge is difficult and problematic. A method was developed to thermally profile long (5-25 kilometers) river reaches by towing in a Lagrangian framework one or two probes that measure temperature, depth, and conductivity. One probe is towed near the streambed and, if used, a second probe is towed near the surface. The probes continuously record data at 1-3-second intervals while a Global Positioning System logs spatial coordinates. The thermal profile provides valuable information about spatial and temporal variations in habitat, and, notably, indicates ground-water discharge areas. This method was developed and tested in the Yakima River Basin, Washington, in summer 2001 during low flows in an extreme drought year. The temperature profile comprehensively documents the longitudinal distribution of a river's temperature regime that cannot be captured by fixed station data. The example profile presented exhibits intra-reach diversity that reflects the many factors controlling the temperature of a parcel of water as it moves downstream. Thermal profiles provide a new perspective on riverine system temperature regimes that represent part of the aquatic habitat template for lotic community patterns.

  11. Method and Apparatus for Monitoring of Daily Activity in Terms of Ground Reaction Forces

    NASA Technical Reports Server (NTRS)

    Whalen, Robert T. (Inventor); Breit, Gregory A. (Inventor)

    2001-01-01

    A device to record and analyze habitual daily activity in terms of the history of gait-related musculoskeletal loading is disclosed. The device consists of a pressure-sensing insole placed into the shoe or embedded in a shoe sole, which detects contact of the foot with the ground. The sensor is coupled to a portable battery-powered digital data logger clipped to the shoe or worn around the ankle or waist. During the course of normal daily activity, the system maintains a record of time-of-occurrence of all non-spurious foot-down and lift-off events. Off line, these data are filtered and converted to a history of foot-ground contact times, from which measures of cumulative musculoskeletal loading, average walking- and running-specific gait speed, total time spent walking and running, total number of walking steps and running steps, and total gait-related energy expenditure are estimated from empirical regressions of various gait parameters to the contact time reciprocal. Data are available as cumulative values or as daily averages by menu selection. The data provided by this device are useful for assessment of musculoskeletal and cardiovascular health and risk factors associated with habitual patterns of daily activity.

  12. Tests of smoothing methods for topological study of galaxy redshift surveys

    NASA Technical Reports Server (NTRS)

    Melott, Adrian L.; Dominik, Kurt G.

    1993-01-01

    Studying the topology of large-scale structure as a way to better understand initial conditions has become more widespread in recent years. Studying topology of simulations (which have periodic boundary conditions) in redshift space produces results compatible with the real topological characteristics of the simulation. Thus we expect we can extract useful information from redshift surveys. However, with nonperiodic boundary conditions, the use of smoothing must result in the loss of information at survey boundaries. In this paper, we test different methods of smoothing samples with nonperiodic boundary conditions to see which most efficiently preserves the topological features of the real distribution. We find that a smoothing method which (unlike most previous published analysis) sums only over cells inside the survey volume produces the best results among the schemes tested.

  13. A rapid method of grading cataract in epidemiological studies and eye surveys.

    PubMed Central

    Mehra, V; Minassian, D C

    1988-01-01

    A rapid method of grading clinically important central lens opacities has been developed for use in eye surveys and in epidemiological studies of cataract and has been field-tested in a specifically designed observer agreement study in a survey of a rural community in Central India. The grading method is based on simple measurement of the area of lens opacity that obscures the red reflex relative to the area of clear red reflex, as visualised through the undilated normal pupil. Good to almost perfect agreements were attained between two ophthalmologists and two trained ophthalmic assistants for overall grades of central lens opacity. Most disagreements were trivial in nature and were concerned with difficulties in distinguishing grade 0 from grade 1, and with hazy appearance of the red reflex in high myopes and in cases of early nuclear sclerosis. Teaching materials including video tape and slides for training survey teams and other workers are in preparation. PMID:3207653

  14. Experimental Methods to Evaluate Science Utility Relative to the Decadal Survey

    NASA Technical Reports Server (NTRS)

    Widergren, Cynthia

    2012-01-01

    The driving factor for competed missions is the science that it plans on performing once it has reached its target body. These science goals are derived from the science recommended by the most current Decadal Survey. This work focuses on science goals in previous Venus mission proposals with respect to the 2013 Decadal Survey. By looking at how the goals compare to the survey and how much confidence NASA has in the mission's ability to accomplish these goals, a method was created to assess the science return utility of each mission. This method can be used as a tool for future Venus mission formulation and serves as a starting point for future development of create science utility assessment tools.

  15. Method and appartus for converting static in-ground vehicle scales into weigh-in-motion systems

    DOEpatents

    Muhs, Jeffrey D.; Scudiere, Matthew B.; Jordan, John K.

    2002-01-01

    An apparatus and method for converting in-ground static weighing scales for vehicles to weigh-in-motion systems. The apparatus upon conversion includes the existing in-ground static scale, peripheral switches and an electronic module for automatic computation of the weight. By monitoring the velocity, tire position, axle spacing, and real time output from existing static scales as a vehicle drives over the scales, the system determines when an axle of a vehicle is on the scale at a given time, monitors the combined weight output from any given axle combination on the scale(s) at any given time, and from these measurements automatically computes the weight of each individual axle and gross vehicle weight by an integration, integration approximation, and/or signal averaging technique.

  16. Sub-surface structure of La Soufrière of Guadeloupe lava dome deduced from a ground-based magnetic survey

    NASA Astrophysics Data System (ADS)

    Bouligand, Claire; Coutant, Olivier; Glen, Jonathan M. G.

    2016-07-01

    In this study, we present the analysis and interpretation of a new ground magnetic survey acquired at the Soufrière volcano on Guadeloupe Island. Observed short-wavelength magnetic anomalies are compared to those predicted assuming a constant magnetization within the sub-surface. The good correlation between modeled and observed data over the summit of the dome indicates that the shallow sub-surface displays relatively constant and high magnetization intensity. In contrast, the poor correlation at the base of the dome suggests that the underlying material is non- to weakly-magnetic, consistent with what is expected for a talus comprised of randomly oriented and highly altered and weathered boulders. The new survey also reveals a dipole anomaly that is not accounted for by a constant magnetization in the sub-surface and suggests the existence of material with decreased magnetization beneath the Soufrière lava dome. We construct simple models to constrain its dimensions and propose that this body corresponds to hydrothermally altered material within and below the dome. The very large inferred volume for such material may have implications on the stability of the dome.

  17. GBFEL-TIE (Ground-Based Free Electron Laser Technology Experiment) sample survey on White Sands Missile Range, New Mexico: The NASA, Stallion, and Orogrande Alternatives. Final report

    SciTech Connect

    Seaman, T.J.; Doleman, W.H.

    1988-09-30

    Three locations on White Sands Missile Range, New Mexico, are under consideration as alternatives for the proposed Ground-Based Free-Electron Laser Technology Integration Experiment (GBFEL-TIE). The study conducted jointly by Prewitt and Associates, Inc., and the Office of Contract Archeology, was designed to provide input into the GBFEL-TIE Draft Environmental Impact Statement concerning the potential impact of the proposed project on cultural resources in each of the alternatives. The input consists of a series of predictions based on data gathered from two sources: (1) a cultural resource sample survey (15%) of two alternatives conducted as part of this study, and (2) from a previous survey of the third alternative. A predictive model was devleoped and applied using these data that estimated the potential impact of the GBFEL-TIE facility on the cultural resources within each alternative. The predictions indicate that the NASA alternatives, by far, the least favorable location for the facility followed by the Orogrande and Stallion Alternatives.

  18. Detection of planets in extremely weak central perturbation microlensing events via next-generation ground-based surveys

    SciTech Connect

    Chung, Sun-Ju; Lee, Chung-Uk; Koo, Jae-Rim E-mail: leecu@kasi.re.kr

    2014-04-20

    Even though the recently discovered high-magnification event MOA-2010-BLG-311 had complete coverage over its peak, confident planet detection did not happen due to extremely weak central perturbations (EWCPs, fractional deviations of ≲ 2%). For confident detection of planets in EWCP events, it is necessary to have both high cadence monitoring and high photometric accuracy better than those of current follow-up observation systems. The next-generation ground-based observation project, Korea Microlensing Telescope Network (KMTNet), satisfies these conditions. We estimate the probability of occurrence of EWCP events with fractional deviations of ≤2% in high-magnification events and the efficiency of detecting planets in the EWCP events using the KMTNet. From this study, we find that the EWCP events occur with a frequency of >50% in the case of ≲ 100 M {sub E} planets with separations of 0.2 AU ≲ d ≲ 20 AU. We find that for main-sequence and sub-giant source stars, ≳ 1 M {sub E} planets in EWCP events with deviations ≤2% can be detected with frequency >50% in a certain range that changes with the planet mass. However, it is difficult to detect planets in EWCP events of bright stars like giant stars because it is easy for KMTNet to be saturated around the peak of the events because of its constant exposure time. EWCP events are caused by close, intermediate, and wide planetary systems with low-mass planets and close and wide planetary systems with massive planets. Therefore, we expect that a much greater variety of planetary systems than those already detected, which are mostly intermediate planetary systems, regardless of the planet mass, will be significantly detected in the near future.

  19. Methods of Gas Phase Capture of Iodine from Fuel Reprocessing Off-Gas: A Literature Survey

    SciTech Connect

    Daryl Haefner

    2007-02-01

    A literature survey was conducted to collect information and summarize the methods available to capture iodine from fuel reprocessing off-gases. Techniques were categorized as either wet scrubbing or solid adsorbent methods, and each method was generally described as it might be used under reprocessing conditions. Decontamination factors are quoted only to give a rough indication of the effectiveness of the method. No attempt is made to identify a preferred capture method at this time, although activities are proposed that would provide a consistent baseline that would aid in evaluating technologies.

  20. Survey of spatial data needs and land use forecasting methods in the electric utility industry

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A representative sample of the electric utility industry in the United States was surveyed to determine industry need for spatial data (specifically LANDSAT and other remotely sensed data) and the methods used by the industry to forecast land use changes and future energy demand. Information was acquired through interviews, written questionnaires, and reports (both published and internal).

  1. EVALUATION OF A MEASUREMENT METHOD FOR FOREST VEGETATION IN A LARGE-SCALE ECOLOGICAL SURVEY

    EPA Science Inventory

    We evaluate a field method for determining species richness and canopy cover of vascular plants for the Forest Health Monitoring Program (FHM), an ecological survey of U.S. forests. Measurements are taken within 12 1-m2 quadrats on 1/15 ha plots in FHM. Species richness and cover...

  2. Random Qualitative Validation: A Mixed-Methods Approach to Survey Validation

    ERIC Educational Resources Information Center

    Van Duzer, Eric

    2012-01-01

    The purpose of this paper is to introduce the process and value of Random Qualitative Validation (RQV) in the development and interpretation of survey data. RQV is a method of gathering clarifying qualitative data that improves the validity of the quantitative analysis. This paper is concerned with validity in relation to the participants'…

  3. A Survey of Singular Value Decomposition Methods and Performance Comparison of Some Available Serial Codes

    NASA Technical Reports Server (NTRS)

    Plassman, Gerald E.

    2005-01-01

    This contractor report describes a performance comparison of available alternative complete Singular Value Decomposition (SVD) methods and implementations which are suitable for incorporation into point spread function deconvolution algorithms. The report also presents a survey of alternative algorithms, including partial SVD's special case SVD's, and others developed for concurrent processing systems.

  4. Examining Stress in Graduate Assistants: Combining Qualitative and Quantitative Survey Methods

    ERIC Educational Resources Information Center

    Mazzola, Joseph J.; Walker, Erin J.; Shockley, Kristen M.; Spector, Paul E.

    2011-01-01

    The aim of this study was to employ qualitative and quantitative survey methods in a concurrent mixed model design to assess stressors and strains in graduate assistants. The stressors most frequently reported qualitatively were work overload, interpersonal conflict, and organizational constraints; the most frequently reported psychological…

  5. Methods of estimating or accounting for neighborhood associations with health using complex survey data.

    PubMed

    Brumback, Babette A; Cai, Zhuangyu; Dailey, Amy B

    2014-05-15

    Reasons for health disparities may include neighborhood-level factors, such as availability of health services, social norms, and environmental determinants, as well as individual-level factors. Investigating health inequalities using nationally or locally representative data often requires an approach that can accommodate a complex sampling design, in which individuals have unequal probabilities of selection into the study. The goal of the present article is to review and compare methods of estimating or accounting for neighborhood influences with complex survey data. We considered 3 types of methods, each generalized for use with complex survey data: ordinary regression, conditional likelihood regression, and generalized linear mixed-model regression. The relative strengths and weaknesses of each method differ from one study to another; we provide an overview of the advantages and disadvantages of each method theoretically, in terms of the nature of the estimable associations and the plausibility of the assumptions required for validity, and also practically, via a simulation study and 2 epidemiologic data analyses. The first analysis addresses determinants of repeat mammography screening use using data from the 2005 National Health Interview Survey. The second analysis addresses disparities in preventive oral health care using data from the 2008 Florida Behavioral Risk Factor Surveillance System Survey. PMID:24723000

  6. Analysis of method of polarization surveying of water surface oil pollution

    NASA Technical Reports Server (NTRS)

    Zhukov, B. S.

    1979-01-01

    A method of polarization surveying of oil films on the water surface is analyzed. Model calculations of contrasted oil and water obtained with different orientations of the analyzer are discussed. The model depends on the spectral range, water transparency and oil film, and the selection of observational direction.

  7. Ground-state properties of LiH by reptation quantum Monte Carlo methods.

    PubMed

    Ospadov, Egor; Oblinsky, Daniel G; Rothstein, Stuart M

    2011-05-01

    We apply reptation quantum Monte Carlo to calculate one- and two-electron properties for ground-state LiH, including all tensor components for static polarizabilities and hyperpolarizabilities to fourth-order in the field. The importance sampling is performed with a large (QZ4P) STO basis set single determinant, directly obtained from commercial software, without incurring the overhead of optimizing many-parameter Jastrow-type functions of the inter-electronic and internuclear distances. We present formulas for the electrical response properties free from the finite-field approximation, which can be problematic for the purposes of stochastic estimation. The α, γ, A and C polarizability values are reasonably consistent with recent determinations reported in the literature, where they exist. A sum rule is obeyed for components of the B tensor, but B(zz,zz) as well as β(zzz) differ from what was reported in the literature. PMID:21445452

  8. Grounding electrode and method of reducing the electrical resistance of soils

    DOEpatents

    Koehmstedt, Paul L.

    1980-01-01

    A first solution of an electrolyte is injected underground into a volume of soil having negative surface charges on its particles. A cationic surfactant suspended in this solution neutralizes these surface charges of the soil particles within the volume. Following the first solution, a cationic asphalt emulsion suspended in a second solution is injected into the volume. The asphalt emulsion diffuses through the volume and electrostatically bonds with additional soil surrounding the volume such that an electrically conductive water repellant shell enclosing the volume is formed. This shell prevents the leaching of electrolyte from the volume into the additional soil. The second solution also contains a dissolved deliquescent salt which draws water into the volume prior to the formation of the shell. When electrically connected to an electrical installation such as a power line tower, the volume constitutes a grounding electrode for the tower.

  9. Determination of land subsidence related to ground-water-level declines using Global Positioning System and leveling surveys in Antelope Valley, Los Angeles and Kern counties, California, 1992

    USGS Publications Warehouse

    Ikehara, M.E.; Phillips, S.P.

    1994-01-01

    A large-scale, land-subsidence monitoring network for Antelope Valley, California, was established, and positions and elevations for 85 stations were measured using Global Positioning System geodetic surveying in spring 1992. The 95-percent confidence (2@) level of accuracy for the elevations calculated for a multiple-constraint adjustment generally ranged from +0.010 meter (0.032 foot) to +0.024 meter (0.078 foot). The magnitudes and rates of land subsidence as of 1992 were calculated for several periods for 218 bench marks throughout Antelope Valley. The maximum measured magnitude of land subsidence that occurred between 1926 and 1992 was 6.0 feet (1.83 meters) at BM 474 near Avenue I and Sierra Highway. Measured or estimated subsidence of 2-7 feet (.61-2.l3 meters) had occurred in a 210- square-mile (542-square-kilometer) area of Antelope Valley, generally bounded by Avenue K, Avenue A, 90th Street West, and 120th Street East, during the same period. Land subsidence in Antelope Valley is caused by aquifer-system compaction, which is related to ground-water-level declines and the presence of fine-grained, compressible sediments. Comparison of potentiomethric-surface, water-level decline, and subsidence-rate maps for several periods indicated a general correlation between water-level declines and the distribution and rate of subsidence in the Lancaster ground-water subbasin. A conservative estimate of the amount of the reduction in storage capacity of the aquifer system in the Lancaster subbasin is about 50,000 acre-feet in the area that has been affected by more than one foot (.30 meters) of subsidence as of 1992. Information on the history of ground-water levels and the distribution and thickness of fine-grained compressible sediments can be used to mitigate continued land subsidence. Future monitoring of ground-water levels and land-surface elevations in subsidence-sensitive regions of Antelope Valley may be an effective means to manage land subsidence.

  10. Ground Control in Mining. Proceedings

    SciTech Connect

    Peng, S.S.

    1991-01-01

    The proceedings contain 36 papers on strata control in underground mining. Specific topics include: support pillar design, mathematical modeling of support-rock interactions, deformation of mine roadways, support recovery, roof bolt design and performance, rock burst prediction methods, detection of abandoned shafts, water influx control, rock mechanical property measurements, ground subsidence effects and forecasting, surveying techniques, and stress analyses. Papers have been processed separately for inclusion on the data base.

  11. Survey of systems safety analysis methods and their application to nuclear waste management systems

    SciTech Connect

    Pelto, P.J.; Winegardner, W.K.; Gallucci, R.H.V.

    1981-11-01

    This report reviews system safety analysis methods and examines their application to nuclear waste management systems. The safety analysis methods examined include expert opinion, maximum credible accident approach, design basis accidents approach, hazard indices, preliminary hazards analysis, failure modes and effects analysis, fault trees, event trees, cause-consequence diagrams, G0 methodology, Markov modeling, and a general category of consequence analysis models. Previous and ongoing studies on the safety of waste management systems are discussed along with their limitations and potential improvements. The major safety methods and waste management safety related studies are surveyed. This survey provides information on what safety methods are available, what waste management safety areas have been analyzed, and what are potential areas for future study.

  12. Multidisciplinary teams, and parents, negotiating common ground in shared-care of children with long-term conditions: A mixed methods study

    PubMed Central

    2013-01-01

    Background Limited negotiation around care decisions is believed to undermine collaborative working between parents of children with long-term conditions and professionals, but there is little evidence of how they actually negotiate their respective roles. Using chronic kidney disease as an exemplar this paper reports on a multi-method study of social interaction between multidisciplinary teams and parents as they shared clinical care. Methods Phases 1 and 2: a telephone survey mapping multidisciplinary teams’ parent-educative activities, and qualitative interviews with 112 professionals (Clinical-psychologists, Dietitians, Doctors, Nurses, Play-specialists, Pharmacists, Therapists and Social-workers) exploring their accounts of parent-teaching in the 12 British children’s kidney units. Phase 3: six ethnographic case studies in two units involving observations of professional/parent interactions during shared-care, and individual interviews. We used an analytical framework based on concepts drawn from Communities of Practice and Activity Theory. Results Professionals spoke of the challenge of explaining to each other how they are aware of parents’ understanding of clinical knowledge, and described three patterns of parent-educative activity that were common across MDTs: Engaging parents in shared practice; Knowledge exchange and role negotiation, and Promoting common ground. Over time, professionals had developed a shared repertoire of tools to support their negotiations with parents that helped them accomplish common ground during the practice of shared-care. We observed mutual engagement between professionals and parents where a common understanding of the joint enterprise of clinical caring was negotiated. Conclusions For professionals, making implicit knowledge explicit is important as it can provide them with a language through which to articulate more clearly to each other what is the basis of their intuition-based hunches about parents’ support needs

  13. The Model Experiments and Finite Element Analysis on Deformation and Failure by Excavation of Grounds in Foregoing-roof Method

    NASA Astrophysics Data System (ADS)

    Sotokoba, Yasumasa; Okajima, Kenji; Iida, Toshiaki; Tanaka, Tadatsugu

    We propose the trenchless box culvert construction method to construct box culverts in small covering soil layers while keeping roads or tracks open. When we use this construction method, it is necessary to clarify deformation and shear failure by excavation of grounds. In order to investigate the soil behavior, model experiments and elasto-plactic finite element analysis were performed. In the model experiments, it was shown that the shear failure was developed from the end of the roof to the toe of the boundary surface. In the finite element analysis, a shear band effect was introduced. Comparing the observed shear bands in model experiments with computed maximum shear strain contours, it was found that the observed direction of the shear band could be simulated reasonably by the finite element analysis. We may say that the finite element method used in this study is useful tool for this construction method.

  14. Applications of numerical optimization methods to helicopter design problems: A survey

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1984-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  15. Applications of numerical optimization methods to helicopter design problems - A survey

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1985-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  16. Applications of numerical optimization methods to helicopter design problems - A survey

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1984-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  17. Reconciling simulated melting and ground-state properties of metals with a modified embedded-atom method potential

    NASA Astrophysics Data System (ADS)

    Sushko, G. B.; Verkhovtsev, A. V.; Kexel, Ch; Korol, A. V.; Schramm, S.; Solov'yov, A. V.

    2016-04-01

    We propose a modification of the embedded-atom method-type potential aiming at reconciling simulated melting and ground-state properties of metals by means of classical molecular dynamics. Considering titanium, magnesium, gold, and platinum as case studies, we demonstrate that simulations performed with the modified force field yield quantitatively correctly both the melting temperature of the metals and their ground-state properties. It is shown that the accounting for the long-range interatomic interactions noticeably affects the melting point assessment. The introduced modification weakens the interaction at interatomic distances exceeding the equilibrium one by a characteristic vibration amplitude defined by the Lindemann criterion, thus allowing for the correct simulation of melting, while keeping its behavior in the vicinity of the ground state minimum. The modification of the many-body potential has a general nature and can be applicable to metals with different characteristics of the electron structure as well as for many different molecular and solid state systems experiencing phase transitions.

  18. A field trial of a survey method for estimating the coverage of selective feeding programmes.

    PubMed Central

    Myatt, Mark; Feleke, Teshome; Sadler, Kate; Collins, Steve

    2005-01-01

    OBJECTIVE: To test a survey method for estimating the coverage of selective feeding programmes in humanitarian emergencies. METHODS: The trial survey used a stratified design with strata that were defined using the centric systematic area sample method. Thirty 100 km2 quadrats were sampled. The communities located closest to the centre of each quadrat were sampled using a case-finding approach. FINDINGS: The method proved simple and rapid to implement and allowed overall and per-quadrat coverage to be estimated. Overall coverage was 20.0% (95% confidence intervals, 13.8-26.3%). Per-quadrat coverage ranged from zero (in nine quadrats) to 50% (in one quadrat). Coverage was highest in the quadrats closest to therapeutic feeding centres and in quadrats containing major roads leading to the towns in which therapeutic feeding centres were located. CONCLUSION: The method should be used, in preference to WHO Expanded Programme on Immunization (EPI)-derived survey methods, for estimating the coverage of selective feeding programmes. Its use should also be considered when evaluating the coverage of other selective entry programmes or when coverage is likely to be spatially inhomogeneous. PMID:15682245

  19. The U.S. Geological Survey Modular Ground-Water Model - PCGN: A Preconditioned Conjugate Gradient Solver with Improved Nonlinear Control

    USGS Publications Warehouse

    Naff, Richard L.; Banta, Edward R.

    2008-01-01

    The preconditioned conjugate gradient with improved nonlinear control (PCGN) package provides addi-tional means by which the solution of nonlinear ground-water flow problems can be controlled as compared to existing solver packages for MODFLOW. Picard iteration is used to solve nonlinear ground-water flow equations by iteratively solving a linear approximation of the nonlinear equations. The linear solution is provided by means of the preconditioned conjugate gradient algorithm where preconditioning is provided by the modi-fied incomplete Cholesky algorithm. The incomplete Cholesky scheme incorporates two levels of fill, 0 and 1, in which the pivots can be modified so that the row sums of the preconditioning matrix and the original matrix are approximately equal. A relaxation factor is used to implement the modified pivots, which determines the degree of modification allowed. The effects of fill level and degree of pivot modification are briefly explored by means of a synthetic, heterogeneous finite-difference matrix; results are reported in the final section of this report. The preconditioned conjugate gradient method is coupled with Picard iteration so as to efficiently solve the nonlinear equations associated with many ground-water flow problems. The description of this coupling of the linear solver with Picard iteration is a primary concern of this document.

  20. Is the simple auger coring method reliable for below-ground standing biomass estimation in Eucalyptus forest plantations?

    PubMed Central

    Levillain, Joseph; Thongo M'Bou, Armel; Deleporte, Philippe; Saint-André, Laurent; Jourdan, Christophe

    2011-01-01

    Background and Aims Despite their importance for plant production, estimations of below-ground biomass and its distribution in the soil are still difficult and time consuming, and no single reliable methodology is available for different root types. To identify the best method for root biomass estimations, four different methods, with labour requirements, were tested at the same location. Methods The four methods, applied in a 6-year-old Eucalyptus plantation in Congo, were based on different soil sampling volumes: auger (8 cm in diameter), monolith (25 × 25 cm quadrate), half Voronoi trench (1·5 m3) and a full Voronoi trench (3 m3), chosen as the reference method. Key Results With the reference method (0–1m deep), fine-root biomass (FRB, diameter <2 mm) was estimated at 1·8 t ha−1, medium-root biomass (MRB diameter 2–10 mm) at 2·0 t ha−1, coarse-root biomass (CRB, diameter >10 mm) at 5·6 t ha−1 and stump biomass at 6·8 t ha−1. Total below-ground biomass was estimated at 16·2 t ha−1 (root : shoot ratio equal to 0·23) for this 800 tree ha−1 eucalypt plantation density. The density of FRB was very high (0·56 t ha−1) in the top soil horizon (0–3 cm layer) and decreased greatly (0·3 t ha−1) with depth (50–100 cm). Without labour requirement considerations, no significant differences were found between the four methods for FRB and MRB; however, CRB was better estimated by the half and full Voronoi trenches. When labour requirements were considered, the most effective method was auger coring for FRB, whereas the half and full Voronoi trenches were the most appropriate methods for MRB and CRB, respectively. Conclusions As CRB combined with stumps amounted to 78 % of total below-ground biomass, a full Voronoi trench is strongly recommended when estimating total standing root biomass. Conversely, for FRB estimation, auger coring is recommended with a design pattern accounting for the spatial variability of fine-root distribution. PMID

  1. The Kenya AIDS Indicator Survey 2012: Rationale, Methods, Description of Participants, and Response Rates

    PubMed Central

    Waruiru, Wanjiru; Kim, Andrea A.; Kimanga, Davies O.; Ng’ang’a, James; Schwarcz, Sandra; Kimondo, Lucy; Ng’ang’a, Anne; Umuro, Mamo; Mwangi, Mary; Ojwang’, James K.; Maina, William K.

    2016-01-01

    Background Cross-sectional population-based surveys are essential surveillance tools for tracking changes in HIV epidemics. In 2007, Kenya implemented the first AIDS Indicator Survey [Kenya AIDS Indicator Survey (KAIS) 2007)], a nationally representative, population-based survey that collected demographic and behavioral data and blood specimens from individuals aged 15–64 years. Kenya’s second AIDS Indicator Survey (KAIS 2012) was conducted to monitor changes in the epidemic, evaluate HIV prevention, care, and treatment initiatives, and plan for an efficient and effective response to the HIV epidemic. Methods KAIS 2012 was a cross-sectional 2-stage cluster sampling design, household-based HIV serologic survey that collected information on households as well as demographic and behavioral data from Kenyans aged 18 months to 64 years. Participants also provided blood samples for HIV serology and other related tests at the National HIV Reference Laboratory. Results Among 9300 households sampled, 9189 (98.8%) were eligible for the survey. Of the eligible households, 8035 (87.4%) completed household-level questionnaires. Of 16,383 eligible individuals aged 15–64 years and emancipated minors aged less than 15 years in these households, 13,720 (83.7%) completed interviews; 11,626 (84.7%) of the interviewees provided a blood specimen. Of 6302 eligible children aged 18 months to 14 years, 4340 (68.9%) provided a blood specimen. Of the 2094 eligible children aged 10–14 years, 1661 (79.3%) completed interviews. Conclusions KAIS 2012 provided representative data to inform a strategic response to the HIV epidemic in the country. PMID:24732819

  2. Simulated likelihood methods for complex double-platform line transect surveys.

    PubMed

    Schweder, T; Skaug, H J; Langaas, M; Dimakos, X K

    1999-09-01

    The conventional line transect approach of estimating effective search width from the perpendicular distance distribution is inappropriate in certain types of surveys, e.g., when an unknown fraction of the animals on the track line is detected, the animals can be observed only at discrete points in time, there are errors in positional measurements, and covariate heterogeneity exists in detectability. For such situations a hazard probability framework for independent observer surveys is developed. The likelihood of the data, including observed positions of both initial and subsequent observations of animals, is established under the assumption of no measurement errors. To account for measurement errors and possibly other complexities, this likelihood is modified by a function estimated from extensive simulations. This general method of simulated likelihood is explained and the methodology applied to data from a double-platform survey of minke whales in the northeastern Atlantic in 1995. PMID:11314993

  3. The survey activities in whole Japan done by Tadataka Inou using the methods of Yoshitoki

    NASA Astrophysics Data System (ADS)

    Hakoiwa, Eiichi

    2005-06-01

    In 2001, 207 sheets of copies of Japanese map were discovered in the Library of Congress of USA in Washington D.C. Those maps called "Daizu" were surveyed by Tadataka Inou who was a surveyor in Edo era. Last year, home coming exhibitions for those maps were held in all over Japan during one year. These highly accurate maps were surveyed by Tadataka Inou who entered into a private school of Yoshitoki Takahashi who was a governmental official regarding astronomy of the Edo shogunate using theory of astronomy and methods of surveying learned from Yoshitoki Inou completed these maps spending 3,727 days and traveling 39,000 km distance on foot.

  4. Stable imaging tracking method based on learning online for ground moving target with multi-DSP processing

    NASA Astrophysics Data System (ADS)

    Li, Yun; Zhong, Sheng

    2011-11-01

    A stable imaging tracking method based on learning online for ground moving target with multi-DSP processing is presented in this paper. Background window is set to track and predict the background image and supervise the intruder. The target learning online based on background prediction revises the accumulated tracking error. Different tracking strategy during different tracking states and risk level of intruder improves the stability and accuracy of tracking system especially in a long time of continual tracking. The parallel processing based on multiple DSP makes a real-time tracking system be possible.

  5. Automatic detection method of lung cancers including ground-glass opacities from chest x-ray CT images

    NASA Astrophysics Data System (ADS)

    Ezoe, Toshiharu; Takizawa, Hotaka; Yamamoto, Shinji; Shimizu, Akinobu; Matsumoto, Tohru; Tateno, Yukio; Iimura, Takeshi; Matsumoto, Mitsuomi

    2002-05-01

    In this paper, we described an algorithm of automatic detection of ground glass opacities (GGO) from X-ray CT images. In this algorithm, at first, pathological shadow candidates are extracted by our variable N-Quoit filter which is a kind of mathematical morphology filter. Next, shadow candidates are classified into some classes using feature values calculated from the shadow candidates. By using discriminate functions, at last, shadow candidates are discriminated between normal shadows and abnormal ones. This method was examined by 38 samples (including GGO's shadows) of chest CT images, and proved to be very effective.

  6. Application of classification-tree methods to identify nitrate sources in ground water

    USGS Publications Warehouse

    Spruill, T.B.; Showers, W.J.; Howe, S.S.

    2002-01-01

    A study was conducted to determine if nitrate sources in ground water (fertilizer on crops, fertilizer on golf courses, irrigation spray from hog (Sus scrofa) wastes, and leachate from poultry litter and septic systems) could be classified with 80% or greater success. Two statistical classification-tree models were devised from 48 water samples containing nitrate from five source categories. Model I was constructed by evaluating 32 variables and selecting four primary predictor variables (??15N, nitrate to ammonia ratio, sodium to potassium ratio, and zinc) to identify nitrate sources. A ??15N value of nitrate plus potassium 18.2 indicated inorganic or soil organic N. A nitrate to ammonia ratio 575 indicated nitrate from golf courses. A sodium to potassium ratio 3.2 indicated spray or poultry wastes. A value for zinc 2.8 indicated poultry wastes. Model 2 was devised by using all variables except ??15N. This model also included four variables (sodium plus potassium, nitrate to ammonia ratio, calcium to magnesium ratio, and sodium to potassium ratio) to distinguish categories. Both models were able to distinguish all five source categories with better than 80% overall success and with 71 to 100% success in individual categories using the learning samples. Seventeen water samples that were not used in model development were tested using Model 2 for three categories, and all were correctly classified. Classification-tree models show great potential in identifying sources of contamination and variables important in the source-identification process.

  7. Method and basis set dependence of anharmonic ground state nuclear wave functions and zero-point energies: Application to SSSH

    NASA Astrophysics Data System (ADS)

    Kolmann, Stephen J.; Jordan, Meredith J. T.

    2010-02-01

    One of the largest remaining errors in thermochemical calculations is the determination of the zero-point energy (ZPE). The fully coupled, anharmonic ZPE and ground state nuclear wave function of the SSSH radical are calculated using quantum diffusion Monte Carlo on interpolated potential energy surfaces (PESs) constructed using a variety of method and basis set combinations. The ZPE of SSSH, which is approximately 29 kJ mol-1 at the CCSD(T)/6-31G∗ level of theory, has a 4 kJ mol-1 dependence on the treatment of electron correlation. The anharmonic ZPEs are consistently 0.3 kJ mol-1 lower in energy than the harmonic ZPEs calculated at the Hartree-Fock and MP2 levels of theory, and 0.7 kJ mol-1 lower in energy at the CCSD(T)/6-31G∗ level of theory. Ideally, for sub-kJ mol-1 thermochemical accuracy, ZPEs should be calculated using correlated methods with as big a basis set as practicable. The ground state nuclear wave function of SSSH also has significant method and basis set dependence. The analysis of the nuclear wave function indicates that SSSH is localized to a single symmetry equivalent global minimum, despite having sufficient ZPE to be delocalized over both minima. As part of this work, modifications to the interpolated PES construction scheme of Collins and co-workers are presented.

  8. Method and basis set dependence of anharmonic ground state nuclear wave functions and zero-point energies: application to SSSH.

    PubMed

    Kolmann, Stephen J; Jordan, Meredith J T

    2010-02-01

    One of the largest remaining errors in thermochemical calculations is the determination of the zero-point energy (ZPE). The fully coupled, anharmonic ZPE and ground state nuclear wave function of the SSSH radical are calculated using quantum diffusion Monte Carlo on interpolated potential energy surfaces (PESs) constructed using a variety of method and basis set combinations. The ZPE of SSSH, which is approximately 29 kJ mol(-1) at the CCSD(T)/6-31G* level of theory, has a 4 kJ mol(-1) dependence on the treatment of electron correlation. The anharmonic ZPEs are consistently 0.3 kJ mol(-1) lower in energy than the harmonic ZPEs calculated at the Hartree-Fock and MP2 levels of theory, and 0.7 kJ mol(-1) lower in energy at the CCSD(T)/6-31G* level of theory. Ideally, for sub-kJ mol(-1) thermochemical accuracy, ZPEs should be calculated using correlated methods with as big a basis set as practicable. The ground state nuclear wave function of SSSH also has significant method and basis set dependence. The analysis of the nuclear wave function indicates that SSSH is localized to a single symmetry equivalent global minimum, despite having sufficient ZPE to be delocalized over both minima. As part of this work, modifications to the interpolated PES construction scheme of Collins and co-workers are presented. PMID:20136303

  9. Autonomous Aerial Refueling Ground Test Demonstration—A Sensor-in-the-Loop, Non-Tracking Method

    PubMed Central

    Chen, Chao-I; Koseluk, Robert; Buchanan, Chase; Duerner, Andrew; Jeppesen, Brian; Laux, Hunter

    2015-01-01

    An essential capability for an unmanned aerial vehicle (UAV) to extend its airborne duration without increasing the size of the aircraft is called the autonomous aerial refueling (AAR). This paper proposes a sensor-in-the-loop, non-tracking method for probe-and-drogue style autonomous aerial refueling tasks by combining sensitivity adjustments of a 3D Flash LIDAR camera with computer vision based image-processing techniques. The method overcomes the inherit ambiguity issues when reconstructing 3D information from traditional 2D images by taking advantage of ready to use 3D point cloud data from the camera, followed by well-established computer vision techniques. These techniques include curve fitting algorithms and outlier removal with the random sample consensus (RANSAC) algorithm to reliably estimate the drogue center in 3D space, as well as to establish the relative position between the probe and the drogue. To demonstrate the feasibility of the proposed method on a real system, a ground navigation robot was designed and fabricated. Results presented in the paper show that using images acquired from a 3D Flash LIDAR camera as real time visual feedback, the ground robot is able to track a moving simulated drogue and continuously narrow the gap between the robot and the target autonomously. PMID:25970254

  10. Autonomous Aerial Refueling Ground Test Demonstration--A Sensor-in-the-Loop, Non-Tracking Method.

    PubMed

    Chen, Chao-I; Koseluk, Robert; Buchanan, Chase; Duerner, Andrew; Jeppesen, Brian; Laux, Hunter

    2015-01-01

    An essential capability for an unmanned aerial vehicle (UAV) to extend its airborne duration without increasing the size of the aircraft is called the autonomous aerial refueling (AAR). This paper proposes a sensor-in-the-loop, non-tracking method for probe-and-drogue style autonomous aerial refueling tasks by combining sensitivity adjustments of a 3D Flash LIDAR camera with computer vision based image-processing techniques. The method overcomes the inherit ambiguity issues when reconstructing 3D information from traditional 2D images by taking advantage of ready to use 3D point cloud data from the camera, followed by well-established computer vision techniques. These techniques include curve fitting algorithms and outlier removal with the random sample consensus (RANSAC) algorithm to reliably estimate the drogue center in 3D space, as well as to establish the relative position between the probe and the drogue. To demonstrate the feasibility of the proposed method on a real system, a ground navigation robot was designed and fabricated. Results presented in the paper show that using images acquired from a 3D Flash LIDAR camera as real time visual feedback, the ground robot is able to track a moving simulated drogue and continuously narrow the gap between the robot and the target autonomously. PMID:25970254

  11. Complementary methods of system usability evaluation: surveys and observations during software design and development cycles.

    PubMed

    Horsky, Jan; McColgan, Kerry; Pang, Justine E; Melnikas, Andrea J; Linder, Jeffrey A; Schnipper, Jeffrey L; Middleton, Blackford

    2010-10-01

    Poor usability of clinical information systems delays their adoption by clinicians and limits potential improvements to the efficiency and safety of care. Recurring usability evaluations are therefore, integral to the system design process. We compared four methods employed during the development of outpatient clinical documentation software: clinician email response, online survey, observations and interviews. Results suggest that no single method identifies all or most problems. Rather, each approach is optimal for evaluations at a different stage of design and characterizes different usability aspect. Email responses elicited from clinicians and surveys report mostly technical, biomedical, terminology and control problems and are most effective when a working prototype has been completed. Observations of clinical work and interviews inform conceptual and workflow-related problems and are best performed early in the cycle. Appropriate use of these methods consistently during development may significantly improve system usability and contribute to higher adoption rates among clinicians and to improved quality of care. PMID:20546936

  12. Chloride mass-balance method for estimating ground water recharge in arid areas: Examples from western Saudi Arabia

    USGS Publications Warehouse

    Bazuhair, A.S.; Wood, W.W.

    1996-01-01

    The chloride mass-balance method, which integrates time and aerial distribution of ground water recharge, was applied to small alluvial aquifers in the wadi systems of the Asir and Hijaz mountains in western Saudi Arabia. This application is an extension of the method shown to be suitable for estimating recharge in regional aquifers in semi-arid areas. Because the method integrates recharge in time and space it appears to be, with certain assumptions, particularly well suited for and areas with large temporal and spatial variation in recharge. In general, recharge was found to be between 3 to 4% of precipitation - a range consistent with recharge rates found in other arid and semi-arid areas of the earth.

  13. Predictive Nuclear Many-Body Theory with Ab Initio Methods: A Brief Survey and A Look Ahead

    NASA Astrophysics Data System (ADS)

    Hergert, Heiko

    2015-10-01

    The reach of ab initio many-body techniques has increased tremendously in recent years, owing to new developments in many-body theory as well as advances in their numerical implementation. Coupled Cluster, Self-Consistent Green's Function, and In-Medium Similarity Renormalization Group (IM-SRG) calculations are routinely performed for isotopes in the A ~ 100 region. Moreover, these techniques have been extended to tackle open-shell nuclei, either directly or through the auxiliary step of deriving valence-space interactions for use with existing Shell Model technology. One of the most powerful aspects of ab initio methods is their capability to provide results for energies and other observables with systematic uncertainties. Together with new accurate nuclear forces (and operators) derived from Chiral Effective Field Theory, they provide a consistent framework--and a road map--for a predictive description of nuclei. This will have a critical impact on the search for the limits of nuclear existence, tests of fundamental symmetries (e.g., the search for neutrinoless double beta decay), our understanding of quenching and effective charges in phenomenological Shell Model calculations etc. Using the Multi-Reference IM-SRG as a representative example, I will survey the current capabilities of ab initio methods with an emphasis on uncertainty quantification, highlight successes in the description of ground-state properties and spectra, and preview upcoming developments like the construction of consistent transition operators.

  14. A Blind Test Experiment in Volcano Geodesy: a Benchmark for Inverse Methods of Ground Deformation and Gravity Data

    NASA Astrophysics Data System (ADS)

    D'Auria, Luca; Fernandez, Jose; Puglisi, Giuseppe; Rivalta, Eleonora; Camacho, Antonio; Nikkhoo, Mehdi; Walter, Thomas

    2016-04-01

    The inversion of ground deformation and gravity data is affected by an intrinsic ambiguity because of the mathematical formulation of the inverse problem. Current methods for the inversion of geodetic data rely on both parametric (i.e. assuming a source geometry) and non-parametric approaches. The former are able to catch the fundamental features of the ground deformation source but, if the assumptions are wrong or oversimplified, they could provide misleading results. On the other hand, the latter class of methods, even if not relying on stringent assumptions, could suffer from artifacts, especially when dealing with poor datasets. In the framework of the EC-FP7 MED-SUV project we aim at comparing different inverse approaches to verify how they cope with basic goals of Volcano Geodesy: determining the source depth, the source shape (size and geometry), the nature of the source (magmatic/hydrothermal) and hinting the complexity of the source. Other aspects that are important in volcano monitoring are: volume/mass transfer toward shallow depths, propagation of dikes/sills, forecasting the opening of eruptive vents. On the basis of similar experiments already done in the fields of seismic tomography and geophysical imaging, we have devised a bind test experiment. Our group was divided into one model design team and several inversion teams. The model design team devised two physical models representing volcanic events at two distinct volcanoes (one stratovolcano and one caldera). They provided the inversion teams with: the topographic reliefs, the calculated deformation field (on a set of simulated GPS stations and as InSAR interferograms) and the gravity change (on a set of simulated campaign stations). The nature of the volcanic events remained unknown to the inversion teams until after the submission of the inversion results. Here we present the preliminary results of this comparison in order to determine which features of the ground deformation and gravity source

  15. A Blind Test Experiment in Volcano Geodesy: a Benchmark for Inverse Methods of Ground Deformation and Gravity Data

    NASA Astrophysics Data System (ADS)

    D'Auria, L.; Fernandez, J.; Puglisi, G.; Rivalta, E.; Camacho, A. G.; Nikkhoo, M.; Walter, T. R.

    2015-12-01

    The inversion of ground deformation and gravity data is affected by an intrinsic ambiguity because of the mathematical formulation of the inverse problem. Current methods for the inversion of geodetic data rely on both parametric (i.e. assuming a source geometry) and non-parametric approaches. The former are able to catch the fundamental features of the ground deformation source but, if the assumptions are wrong or oversimplified, they could provide misleading results. On the other hand, the latter class of methods, even if not relying on stringent assumptions, could suffer from artifacts, especially when dealing with poor datasets. In the framework of the EC-FP7 MED-SUV project we aim at comparing different inverse approaches to verify how they cope with basic goals of Volcano Geodesy: determining the source depth, the source shape (size and geometry), the nature of the source (magmatic/hydrothermal) and hinting the complexity of the source. Other aspects that are important in volcano monitoring are: volume/mass transfer toward shallow depths, propagation of dikes/sills, forecasting the opening of eruptive vents. On the basis of similar experiments already done in the fields of seismic tomography and geophysical imaging, we have devised a bind test experiment. Our group was divided into one model design team and several inversion teams. The model design team devised two physical models representing volcanic events at two distinct volcanoes (one stratovolcano and one caldera). They provided the inversion teams with: the topographic reliefs, the calculated deformation field (on a set of simulated GPS stations and as InSAR interferograms) and the gravity change (on a set of simulated campaign stations). The nature of the volcanic events remained unknown to the inversion teams until after the submission of the inversion results. Here we present the preliminary results of this comparison in order to determine which features of the ground deformation and gravity source

  16. Short assessment of the Big Five: robust across survey methods except telephone interviewing.

    PubMed

    Lang, Frieder R; John, Dennis; Lüdtke, Oliver; Schupp, Jürgen; Wagner, Gert G

    2011-06-01

    We examined measurement invariance and age-related robustness of a short 15-item Big Five Inventory (BFI-S) of personality dimensions, which is well suited for applications in large-scale multidisciplinary surveys. The BFI-S was assessed in three different interviewing conditions: computer-assisted or paper-assisted face-to-face interviewing, computer-assisted telephone interviewing, and a self-administered questionnaire. Randomized probability samples from a large-scale German panel survey and a related probability telephone study were used in order to test method effects on self-report measures of personality characteristics across early, middle, and late adulthood. Exploratory structural equation modeling was used in order to test for measurement invariance of the five-factor model of personality trait domains across different assessment methods. For the short inventory, findings suggest strong robustness of self-report measures of personality dimensions among young and middle-aged adults. In old age, telephone interviewing was associated with greater distortions in reliable personality assessment. It is concluded that the greater mental workload of telephone interviewing limits the reliability of self-report personality assessment. Face-to-face surveys and self-administrated questionnaire completion are clearly better suited than phone surveys when personality traits in age-heterogeneous samples are assessed. PMID:21424189

  17. Ground motion simulation for the 23 August 2011, Mineral, Virginia earthquake using physics-based and stochastic broadband methods

    USGS Publications Warehouse

    Sun, Xiaodan; Hartzell, Stephen; Rezaeian, Sanaz

    2015-01-01

    Three broadband simulation methods are used to generate synthetic ground motions for the 2011 Mineral, Virginia, earthquake and compare with observed motions. The methods include a physics‐based model by Hartzell et al. (1999, 2005), a stochastic source‐based model by Boore (2009), and a stochastic site‐based model by Rezaeian and Der Kiureghian (2010, 2012). The ground‐motion dataset consists of 40 stations within 600 km of the epicenter. Several metrics are used to validate the simulations: (1) overall bias of response spectra and Fourier spectra (from 0.1 to 10 Hz); (2) spatial distribution of residuals for GMRotI50 peak ground acceleration (PGA), peak ground velocity, and pseudospectral acceleration (PSA) at various periods; (3) comparison with ground‐motion prediction equations (GMPEs) for the eastern United States. Our results show that (1) the physics‐based model provides satisfactory overall bias from 0.1 to 10 Hz and produces more realistic synthetic waveforms; (2) the stochastic site‐based model also yields more realistic synthetic waveforms and performs superiorly for frequencies greater than about 1 Hz; (3) the stochastic source‐based model has larger bias at lower frequencies (<0.5  Hz) and cannot reproduce the varying frequency content in the time domain. The spatial distribution of GMRotI50 residuals shows that there is no obvious pattern with distance in the simulation bias, but there is some azimuthal variability. The comparison between synthetics and GMPEs shows similar fall‐off with distance for all three models, comparable PGA and PSA amplitudes for the physics‐based and stochastic site‐based models, and systematic lower amplitudes for the stochastic source‐based model at lower frequencies (<0.5  Hz).

  18. Detecting population declines over large areas with presence-absence, time-to-encounter, and count survey methods.

    PubMed

    Pollock, Jacob E

    2006-06-01

    Ecologists often discount presence-absence surveys as a poor way to gain insight into population dynamics, in part because these surveys are not amenable to many standard statistical tests. Still, presence-absence surveys are sometimes the only feasible alternative for monitoring large areas when funds are limited, especially for sparse or difficult-to-detect species. I undertook a detailed simulation study to compare the power of presence-absence, count, and time-to-encounter surveys to detect regional declines in a population. I used a modeling approach that simulates both population numbers and the monitoring process, accounting for observation and other measurement errors. In gauging the efficacy of presence-absence surveys versus other approaches, I varied the number of survey sites, the spatial variation in encounter rate, the mean encounter rate, and the type of population loss. My results showed that presence-absence data can be as or more powerful than count data in many cases. Quantitative guidelines for choosing between presence-absence surveys and count surveys depend on the biological and logistical constraints governing a conservation monitoring situation. Generally, presence-absence surveys work best when there is little variability in abundance among the survey sites, the organism is rare, and the species is difficult to detect so that the time spent getting to each survey site is less than or equal to the time spent surveying each site. Count surveys work best otherwise. I present a case study with count data on the Northern Flicker (Colaptes auratus) from the North American Breeding Bird Survey to illustrate how the method might be used with field-survey data. The case study demonstrates that a count survey would be the most cost-effective design but would entail reduction in the number of sites. If this site reduction is not desirable, a presence-absence survey would be the most cost-effective survey. PMID:16909580

  19. Multidisciplinary Studies of the Fate and Transport of Contaminants in Ground Water at the U.S. Geological Survey Cape Cod Toxic Substances Hydrology Program Research Site, Massachusetts

    NASA Astrophysics Data System (ADS)

    Leblanc, D. R.; Smith, R. L.; Kent, D. B.; Barber, L. B.; Harvey, R. W.

    2008-12-01

    The U.S. Geological Survey conducts multidisciplinary research on the physical, chemical, and microbiological processes affecting ground-water contaminants of global concern at its Cape Cod Toxic Substances Hydrology Program site in Massachusetts, USA. The work centers on a 6-kilometer-long plume of treated wastewater in a glacial sand and gravel aquifer. The plume is characterized by distinct geochemical zones caused by the biodegradation of organic materials in treated wastewater that was disposed to the aquifer by rapid infiltration during the period 1936-95. A core group of hydrogeologists, geochemists, microbiologists, and geophysicists has been involved in the research effort for more than two decades. The effort has been enhanced by stable funding, a readily accessible site, a relatively simple hydrologic setting, and logistical support from an adjacent military base. The research team uses a three-part approach to plan and conduct research at the site. First, detailed spatial and temporal monitoring of the plume since the late 1970s provides field evidence of important contaminant-transport processes and provides the basis for multidisciplinary, process-oriented studies. Second, ground-water tracer experiments are conducted in various geochemical zones in the plume to study factors that control the rate and extent of contaminant transport. Several arrays of multilevel sampling devices, including an array with more than 15,000 individual sampling points, are used to conduct these experiments. Plume-scale (kilometers) and tracer-test-scale (1- 100 meters) studies are complemented by laboratory experiments and mathematical modeling of flow and reactive transport. Third, results are applied to the treated-wastewater plume, other contaminant plumes at the military base, and other sites nationally to evaluate the applicability of the findings and to point toward further research. Examples of findings to date include that (1) macrodispersivity can be related to

  20. EVALUATION OF SAMPLING AND FIELD FILTRATION METHODS FOR THE ANALYSIS OF TRACE METALS IN GROUND WATER

    EPA Science Inventory

    Selected groundwater sampling and filtering methods were evaluated to determine their effects on field parameters and trace metal concentrations in samples collected under several types of field conditions. he study focused on sampling in conventional standpipe monitoring wells u...