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1

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

PubMed

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

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

2011-03-01

2

Correlated supernova systematics and ground based surveys  

SciTech Connect

Supernova distances provide a direct probe of cosmic acceleration, constraining dark energy. This leverage increases with survey redshift depth at a rate bounded by the systematic uncertainties. We investigate the impact of a wavelength-dependent, global correlation model of systematics in comparison to the standard local-redshift correlation model. This can arise from subclass uncertainties as features in the supernova spectrum redshift out of the observer photometric filters or spectral range. We explore the impact of such a systematic on ground-based supernova surveys such as Dark Energy Survey and LSST, finding distinctive implications. Extending the wavelength sensitivity to 1.05 ?m through ''extreme red'' CCDs can improve the dark energy figure of merit by up to a factor 2.

Kim, Alex G.; Linder, Eric V., E-mail: agkim@lbl.gov, E-mail: evlinder@lbl.gov [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

2011-06-01

3

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)

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.

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

2013-02-01

4

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

5

Ground-cover measurements: assessing correlation among aerial and ground-based methods.  

PubMed

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. PMID:18446407

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

2008-12-01

6

INTRODUCTION & SURVEY METHODS BACKGROUND  

E-print Network

This report presents the results of the eighth administration of the Massachusetts Youth Risk Behavior Survey (MYRBS), and the seventh consecutive administration that can be considered fully representative of public high school students across the Commonwealth (1a). The MYRBS is a student health survey that has been conducted

unknown authors

7

Generating Ground Reference Data for a Global Impervious Surface Survey  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

8

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

NASA Astrophysics Data System (ADS)

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.

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

2010-12-01

9

Simulating the Performance of Ground-Based Optical Asteroid Surveys  

NASA Astrophysics Data System (ADS)

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 yet unverified survey cadences (e.g. the baseline LSST cadence) that sparsely spread the observations required for detection over several days or weeks.

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

10

Straussian Grounded-Theory Method: An Illustration  

ERIC Educational Resources Information Center

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…

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

2012-01-01

11

Comparing LiDAR-Generated to Ground-Surveyed Channel Cross-Sectional Profiles  

E-print Network

and Ranging (LiDAR) holds promise to provide an alternative to traditional ground-based survey methods on Cal Poly's Swanton Pacific Ranch, near Santa Cruz, CA. Three LiDAR datasets were compared in this study, with flights in 2002, 2008, and 2010, a period of rapid improvement in LiDAR technology. Visual

Standiford, Richard B.

12

Ground solar radius survey in view of microsatellite missions  

NASA Astrophysics Data System (ADS)

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).

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

13

Comparison of Satellite Surveying to Traditional Surveying Methods for the Resources Industry  

NASA Astrophysics Data System (ADS)

Modern ground-based survey methods involve detailed survey, which provides three-space co-ordinates for surveyed points, to a high level of accuracy. The instruments are operated by surveyors, who process the raw results to create survey location maps for the subject of the survey. Such surveys are conducted for a location or region and referenced to the earth global co- ordinate system with global positioning system (GPS) positioning. Due to this referencing the survey is only as accurate as the GPS reference system. Satellite survey remote sensing utilise satellite imagery which have been processed using commercial geographic information system software. Three-space co-ordinate maps are generated, with an accuracy determined by the datum position accuracy and optical resolution of the satellite platform.This paper presents a case study, which compares topographic surveying undertaken by traditional survey methods with satellite surveying, for the same location. The purpose of this study is to assess the viability of satellite remote sensing for surveying in the resources industry. The case study involves a topographic survey of a dune field for a prospective mining project area in Pakistan. This site has been surveyed using modern surveying techniques and the results are compared to a satellite survey performed on the same area.Analysis of the results from traditional survey and from the satellite survey involved a comparison of the derived spatial co- ordinates from each method. In addition, comparisons have been made of costs and turnaround time for both methods.The results of this application of remote sensing is of particular interest for survey in areas with remote and extreme environments, weather extremes, political unrest, poor travel links, which are commonly associated with mining projects. Such areas frequently suffer language barriers, poor onsite technical support and resources.

Osborne, B. P.; Osborne, V. J.; Kruger, M. L.

14

Appendix of Surveys from the Provider Survey Methods Workshop  

Cancer.gov

In November 2010, ARP sponsored a Provider Survey Methods Workshop to review and discuss current methodologies in designing and fielding large-scale surveys of physicians and medical group practices. The workshop included a review of methods used in fielding and reporting on large-scale provider surveys over the decade 2000-2010. The following is an Appendix of the 117 surveys included in the review.

15

Survey of Anomaly Detection Methods  

SciTech Connect

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.

Ng, B

2006-10-12

16

40 CFR 141.401 - Sanitary surveys for ground water systems.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Sanitary surveys for ground water systems. 141.401 Section 141.401...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2013-07-01

17

40 CFR 141.401 - Sanitary surveys for ground water systems.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Sanitary surveys for ground water systems. 141.401 Section 141.401...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2012-07-01

18

40 CFR 141.401 - Sanitary surveys for ground water systems.  

Code of Federal Regulations, 2011 CFR

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

2011-07-01

19

Buried Utility Pipeline Mapping based on Street Survey and Ground Penetrating Radar  

E-print Network

Buried Utility Pipeline Mapping based on Street Survey and Ground Penetrating Radar Huanhuan Chen1 is often conducted using sensor devices, such as ground penetrating radar (GPR). However, these are costly

Leeds, University of

20

40 CFR 141.401 - Sanitary surveys for ground water systems.  

...2014-07-01 false Sanitary surveys for ground water systems. 141.401 Section 141.401...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2014-07-01

21

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

SciTech Connect

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 measurements to refine interpretations of AEM data; and (3) Improve the calibration and correlation of AEM information. The potential benefits of this project are as follows: (1) Develop a tool to map subsurface units at the Hanford Site in a rapid and cost effective manner; (2) Map groundwater pathways within the River Corridor; and (3) Aid development of the conceptual site model. If anomalies observed in the AEM data can be correlated with subsurface geology, then the rapid scanning and non-intrusive capabilities provided by the airborne surveys can be used at the Hanford Site to screen for areas that warrant further investigation.

PETERSEN SW

2010-12-02

22

The Erosion of a Method: Examples from Grounded Theory  

ERIC Educational Resources Information Center

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…

Greckhamer, Thomas; Koro-Ljungberg, Mirka

2005-01-01

23

The Neural Network Method of Corrosion Diagnosis for Grounding Grid  

SciTech Connect

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.

Hou Zaien [School of Science, Shaanxi University of Sci. and Tech., Xi'an, 710021 (China); Duan Fujian [School of Science, Guilin University of Electronic Tech., Guilin, 541004 (China); Zhang Kecun [School of Science, Xi'an Jiaotong University, Xi'an, 710049 (China)

2008-11-06

24

Interactions between Slope and Lake Sedimentary Processes: Study from Aerial Imagery and Ground Penetrating Radar Survey  

E-print Network

conducted with the use of ground- penetrating radar, supplemented with observation of surface sedimentology Penetrating Radar Survey In the Alps of New Zealand Jordan Miller1 , Christopher Gomez1,* , Heather Purdie1 1Interactions between Slope and Lake Sedimentary Processes: Study from Aerial Imagery and Ground

Paris-Sud XI, Université de

25

Erosional corridor evolution in south-central British Columbia: insights from ground-penetrating radar surveys  

E-print Network

Erosional corridor evolution in south-central British Columbia: insights from ground-penetrating.25-1 km wide erosional corridor, with long upslope sections, contains both hummocks and an esker. Ground-penetrating radar surveys Matthew J. Burke, Tracy A. Brennand and Andrew J. Perkins Department of Geography, Simon

Brennand, Tracy

26

Improved acoustic surveys that save time and money: integrating fisheries and ground-discrimination acoustic technologies  

Microsoft Academic Search

Field surveys involving ship time are notoriously costly. Whilst continuous acoustic surveys provide good value in terms of their data richness and spatial coverage when compared to point sample surveys (e.g. trawls, dredges, grabs), there is scope to improve survey methods and provide value-added data. We present technical details and an example application of an approach that maximises survey efficiency

Steven Mackinson; Steven Freeman; Roger Flatt; Bill Meadows

2004-01-01

27

Calibration of the DRASTIC ground water vulnerability mapping method  

USGS Publications Warehouse

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.

Rupert, M. G.

2001-01-01

28

Image registration methods: a survey  

Microsoft Academic Search

This paper aims to present a review of recent as well as classic image registration methods. Image registration is the process of overlaying images (two or more) of the same scene taken at different times, from different viewpoints, and\\/or by different sensors. The registration geometrically align two images (the reference and sensed images). The reviewed approaches are classified according to

Barbara Zitova ´; Jan Flusser

2003-01-01

29

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

USGS Publications Warehouse

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.

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

2003-01-01

30

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

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

31

Ground-penetrating radar for landscape archaeology: Method and applications  

Microsoft Academic Search

Ground-penetrating radar mapping allows for a three-dimensional analysis of archaeological features within the context of landscape studies. The method's ability to measure the intensity of radar reflections from as deep as 5 meters in the ground can produce images and maps of buried features not visible on the surface. A study was conducted in the desert of the American Southwest

L. B. Conyers

32

Ground-based variability surveys towards Centaurus A: worthwhile or not?  

NASA Astrophysics Data System (ADS)

Context: Difference imaging has proven to be a powerful technique for detecting and monitoring the variability of unresolved stellar sources in M 31. Using this technique in surveys of galaxies outside the Local Group could have many interesting applications. Aims: The goal of this paper is to test difference imaging photometry on Centaurus A, the nearest giant elliptical galaxy, at a distance of 4 Mpc. Methods: We obtained deep photometric data with the Wide Field Imager at the ESO/MPG 2.2 m at La Silla spread over almost two months. Applying the difference imaging photometry package DIFIMPHOT, we produced high-quality difference images and detected variable sources. The sensitivity of the current observational setup was determined through artificial residual tests. Results: In the resulting high-quality difference images, we detect 271 variable stars. We find a difference flux detection limit corresponding to mR ? 24.5. Based on a simple model of the halo of Centaurus A, we estimate that a ground-based microlensing survey would detect in the order of 4 microlensing events per year due to lenses in the halo. Conclusions: Difference imaging photometry works very well at the distance of Centaurus A and promises to be a useful tool for detecting and studying variable stars in galaxies outside the local group. For microlensing surveys, a higher sensitivity is needed than achieved here, which would be possible with a large ground-based telescope or space observatory with wide-field imaging capabilities. Catalogue is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/478/755

de Jong, J. T. A.; Kuijken, K. H.; Héraudeau, P.

2008-02-01

33

30 CFR 75.700-1 - Approved methods of grounding.  

Code of Federal Regulations, 2010 CFR

...neutral conductor; in all other systems, the following methods of grounding will be approved: (a) A solid connection to a borehole casing having low resistance to earth; (b) A solid connection to metal waterlines having low resistance to...

2010-07-01

34

Title Using Datasets for Teaching Survey Methods  

E-print Network

The study analysed ways of reducing barriers to the use of quantitative data sets in teaching survey research methods at the undergraduate level in a sociology course. Both the QAA benchmarking statements for Sociology and the ESRC revised postgraduate training guidelines specify the need to train HE students in quantitative research skills. However, according to research conducted by the Task Force on The Use of Numeric Data in Learning & Teaching (funded by the JISC), teachers in HE institutions face barriers using data sets when teaching survey methods. Furthermore, students tend to find quantitative methods modules dull and uninvolving. Research reports that HE teachers face barriers in teaching survey methods due to: datasets that are unwieldy to use or access; lack of knowledge about available datasets; inadequate teaching material accompanying datasets and lack of support in teaching survey methods. The results suggest that ‘new teaching datasets, online tools…and new modes of support…may be needed to prepare teachers for the challenge of teaching quantitative skills and critical numeracy… ’ (Rice 2002:1). Activities

unknown authors

35

Survey on large scale system control methods  

NASA Technical Reports Server (NTRS)

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.

Mercadal, Mathieu

1987-01-01

36

Identification of School Bullies by Survey Methods  

ERIC Educational Resources Information Center

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…

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

2006-01-01

37

A Survey of Methods and Materials.  

ERIC Educational Resources Information Center

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…

Gillis, Candida; And Others

38

Study on Tunnel-ground Controlled Source Electromagnetic Method  

NASA Astrophysics Data System (ADS)

In order to carry out 3D exploration of deeper mineral ores and overcome the difficulty and improve the accuracy of ores exploration, we will develop artificial source tunnel(wells) - ground 3D detection technology of resistivity parameter, which technology can excite ore body in multiple directions and have the advantage of obtaining plenteous electrical information. According to current literature, achievements on Tunnel-ground Electromagnetic Method are mainly electromagnetic imaging technology of inter-well and well-ground polarization method. There are few referenced experiences about tunnel-ground controlled source electromagnetic method. So, in order to get to know about this technology, it is necessary to carry out the numerical simulation of electromagnetic field of controlled source tunnel-ground electromagnetic method. Results indicate: 1. when excited signal is transmitted from surficial source, Cagniard resistivity and phase calculated by electromagnetic components from underground receivers in the far field can reflect the abnormal body clearly. 2. when the artificial sources are located in the tunnel of well, the exploration data obtaining from receivers on the ground far field can be inversion similar to magnetetolluric data. 3. According to the observation in the tunnel or well above the abnormal body, it is easy to find the deeper objects.

Jing, J.; Jin, S.; Wei, W.; Deng, M.; Ye, G.

2010-12-01

39

Transport Methods in 3DTV - A Survey  

Microsoft Academic Search

We present a survey of transport methods for 3-D video ranging from early analog 3DTV systems to most recent digital technologies that show promise in designing 3DTV systems of tomorrow. Potential digital transport architectures for 3DTV include the DVB architecture for broadcast and the Internet Protocol (IP) architecture for wired or wireless streaming. There are different multiview representation\\/compression methods for

Gozde Bozdagi Akar; A. Murat Tekalp; Christoph Fehn; M. Reha Civanlar

2007-01-01

40

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...

41

18th AIAA Aerospace Ground Testing Survey of Short Duration, Hypersonic and Hypervelocity Facilities  

E-print Network

18th AIAA Aerospace Ground Testing Conference #12;94-2491 Survey of Short Duration, Hypersonic 76019-0018 Hypersonic and hypervelocity testing relies to a large extent on short duration facilities activity con- fined mostly to hypersonic and hypervelocity regimes. Early development of such facilities

Texas at Arlington, University of

42

Exoplanets -New Results from Space and Ground-based Surveys  

NASA Astrophysics Data System (ADS)

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 Earth. Its geology, from lakes and seas to broad river valleys and mountains, while carved in ice is, in its balance of processes, again most like Earth. Beneath this panoply of Earth-like processes an ice crust floats atop what appears to be a liquid water ocean. Titan is also rich in organic molecules—more so in its surface and atmosphere than anyplace in the solar system, including Earth [4]. These molecules were formed in the atmosphere, deposited on the surface and, in coming into contact with liquid water may undergo an aqueous chemistry that could replicate aspects of life's origins. I will discuss our current understanding of Titan's complex environment in view of recent exploration, in particular on the atmospheric structure (temperature and composition), and the surface nature. I will show how these and other elements can give us clues as to the origin and evolution of the satellite, and how they connect to the observations of the planet and the other satellites and rings. Future space missions to Titan can help us understand the kronian and also our Solar System as a whole. In particular, I will describe the future exploration of Titan and the Saturnian System with TSSM, a mission studied jointly by ESA and NASA in 2008 [1] and prioritized second for a launch around 2023-2025. TSSM comprises a Titan Orbiter provided by NASA that would carry two Titan in situ elements provided by ESA: a montgolfiere and a lake-landing lander. The mission would arrive 9 years later for a 4-year duration in the Saturn system. Following delivery of the ESA in situ elements to Titan, the Titan Orbiter would explore the Saturn system via a 2-year tour that includes Enceladus and Titan flybys. The montgolfiere would last at least 6 months at Titan and the lake lander 8-10 hours. Following the Saturn system tour, the Titan Orbiter would culminate in a —2-year orbit around Titan. References 1. TSSM and EJSM NASA/ESA Joint Summary Report, 16 January 2009 2. Coustenis et al. (2008). TandEM: Titan and Enceladus mission. Experimenta( Astron-omy, 23, 893-946. 3. Coustenis, A.,

Udry, Stephane

43

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

USGS Publications Warehouse

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.

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

1996-01-01

44

Biomass Estimation by ALOS/PALSAR over Boreal Forest in Alaska Accompanied with Ground-based Forest Survey  

NASA Astrophysics Data System (ADS)

For the better understanding of the carbon cycle in the global ecosystem, investigations on the spatio- temporal variation of the carbon stock which is stored as vegetation biomass is important. The sensor "PALSAR (Phased Array type L-band Synthetic Aperture Radar)" of the satellite "ALOS (Advanced Land Observing Satellite)", launched in January 2006, provides the information which can be used for the above- ground biomass estimation. To derive the forest biomass from satellite measurement, it is inevitable to acquire in situ above-ground biomass by ground-based survey. In July 2007, a forest survey was carried out in the south-north transect (about 300km long) along the Trans-Alaska Pipeline which profiles the ecotone from boreal forest to tundra in Alaska. 29 forests along the transect were targeted for the survey, and their biomasses were measured by the combination method of Bitterlich Angle Count Sampling method and Sampled-tree Measuring method. Consequently, it was revealed that the forest biomass distributes from 5 to 100 ton/ha (dried matter). These ground-based biomass measurements at 29 forests were compared with the signal in 20 mages of ALOS/PALSAR (HV polarization mode) that cover the 29 forests in July or August 2007. In addition, 16 areas of grassland in the images were picked for the reference value of zero forest biomass. The result showed a positive strong (r = 0.84) and linear relationship between them, demonstrating a feasibility of ALOS/PALSAR for the mapping of the biomass in boreal forests.

Suzuki, R.; Kim, Y.; Ishii, R.

2008-12-01

45

SURVEY RESEARCH LABORATORY UNIVERSITY OF ILLINOIS AT CHICAGO Conference on Health Survey Research Methods  

E-print Network

Survey Research Methods April 8­11, 2011 CALL FOR PAPERS The Tenth Conference on Health Survey Research Methods (CHSRM) will continue the series that began in 1975 to discuss new, innovative survey research methods that improve the quality of health survey data. The CHSRM will bring together researchers

Illinois at Chicago, University of

46

GPR and bulk ground resistivity surveys in graveyards: locating unmarked burials in contrasting soil types.  

PubMed

With graveyards and cemeteries globally being increasingly designated as full, there is a growing need to identify unmarked burial positions to find burial space or exhume and re-inter if necessary. In some countries, for example the U.S. and U.K., burial sites are not usually re-used; however, most graveyard and cemetery records do not have maps of positions. One non-invasive detection method is near-surface geophysics, but there has been a lack of research to-date on optimal methods and/or equipment configuration. This paper presents three case studies in contrasting burial environments, soil types, burial styles and ages in the U.K. Geophysical survey results reveal unmarked burials could be effectively identified from these case studies that were not uniform or predicted using 225 MHz frequency antennae GPR 2D 0.5 m spaced profiles. Bulk ground electrical surveys, rarely used for unmarked burials, revealed 1 m probe spacings were optimal compared to 0.5 m, with datasets needing 3D detrending to reveal burial positions. Results were variable depending upon soil type; in very coarse soils GPR was optimal; whereas resistivity was optimal in clay-rich soils and both were optimal in sandy and black earth soils. Archaeological excavations revealed unmarked burials, extra/missing individuals from parish records and a variety of burial styles from isolated, brick-lined, to vertically stacked individuals. Study results, evidence unmarked burial targets were significantly different from clandestine burials of murder victims which are used as analogues. PMID:24559798

Hansen, James D; Pringle, Jamie K; Goodwin, Jon

2014-04-01

47

Ground-penetrating radar survey use for documentation of a historic cemetery in Sand Brook Township, NJ  

NASA Astrophysics Data System (ADS)

Much of the early history of the United States can be traced through old cemetery sites scattered throughout the Northeast. Today, many historic burial sites are in less-than-ideal condition, as upkeep of old grave locations is neglected and written records of the details of cemeteries are lost through time. In addition, tombstones can be rendered invisible at the surface through erosion and soil movement processes, both natural and anthropogenic in origin. We document the ground-penetrating radar (GPR) survey of a graveyard dating back to the colonial era, and still in use today. A control survey of locations with known burials shows that disruption of strata at grave sites is clearly visible using 200 and 400 MHz antennas; another control survey in an area where graves are not expected demonstrates the undisturbed stratigraphy of the slump deposit comprising the hill where the graveyard is located. Subsequent survey of areas within and near the cemetery without marked graves has allowed us to document the positions of individual burials and, in at least one case, even rediscover an original tombstone beneath ~5 cm of modern soil. This study demonstrates that ground-penetrating radar serves as an effective non- invasive method for documentation and restoration of historical-era burials.

Bitting, K. S.; Nikulin, A.; Earley, R. J.; Swisher, C.

2007-12-01

48

The Constant Comparative Analysis Method Outside of Grounded Theory  

ERIC Educational Resources Information Center

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…

Fram, Sheila M.

2013-01-01

49

Real-time collision avoidance method for unmanned ground vehicle  

Microsoft Academic Search

In this paper, a real-time collision avoidance method is proposed for unmanned ground vehicles (UGV). To ensure real-time implementation, virtual force fields are calculated in on dimensional space. The steering force field is generated by the steering command either transmitted in the remote control station or calculated in the autonomous navigation system (ANS) of the UGV. The obstacle force field

TokSon Choe; Jin Wook Hur; Jeong Sook Chae; Yong-Woon Park

2008-01-01

50

Ground solar radius survey in view of the Picard microsatellite mission  

NASA Astrophysics Data System (ADS)

A survey of the Solar radius has been initiated in 1975 by Francis Laclare, at the Calern site of the OCA (Observatoire de la Côte d'Azur), which have been chosen for hosting the ground segment of the 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. We look into the Visual series and compare its variations with the Solar cycle, to find an opposing phase, globally and at the different times : maximum, minimum, raise and fall of the cycles. Parallel to that series, CCD measurements were made with the same instrument and gave results which are perfectly blended together, inside narrow error bars. Located next to the Astrolabe, DORAYSOL (Définition et Observation du Rayon Solaire) is a second generation instrument, keeping the strong points of its predecessor and designed to increase the number of CCD measurements and to be automated eventually. Since 1999, both series overlap beautifully and the number of radius data obtained give access to less-than-a-month radius variations, for the first time at the ground level. A few words are added to explain the pattern of the PICARD ground segment next to those instruments at Calern observatory, as well as the ground network intended to carry out the Sun's Radius ground survey (R2S3: Réseau de Suivi au Sol du Rayon Solaire).

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

51

High performance ground penetrating radar survey of TA-49/Area 2. Final report  

SciTech Connect

The results of high performance ground penetrating radar study of Area 2 at Technical Area 49 are presented. The survey was commissioned as part of Los Alamos Laboratory`s continuing Environmental Remediation program and was completed and analyzed before borehole studies in Area 2 were started. Based upon the ground penetrating radar results, the location of one of the planned boreholes was moved to assure the drilling area was as safe as possible. While earlier attempts to use commercial radar devices at this facility had not been successful, the radar and digital processing system developed at Los Alamos were able to significantly improve the buried physical detail of the site.

Hoeberling, R.F. [Los Alamos National Lab., NM (United States); Rangel, M.J. III [Analysis Programming Processing Instrumentation, Santa Barbara, CA (United States)

1994-09-01

52

A design method for hybrid ground-source heat pumps  

SciTech Connect

Although ground-source heat pumps (GSHPs) are recognized to be outstanding heating, cooling, and water-heating systems, a significant barrier to wider application of this technology is a high first cost, which makes short-term economics unattractive. One possible alternative that can lower first cost is the hybrid ground-source heat pump (HyGSHP) system. In many large buildings in the US, the required GSHP bore length for cooling is much greater than the required heating length. In these cases, it is possible to displace a large portion of the system cost by installing a ground loop large enough to meet the heating requirement in parallel with a fluid cooler or cooling tower to handle the cooling requirement. The project on which this paper reports was proposed to analyze the impact of fluid coolers or cooling towers upon GSHP loop length design, annual ground loop heat buildup, system demand, and annual energy use. From this analysis, a design method was to be developed that simultaneously sizes the ground loop and fluid cooler. The conclusions of the project have attempted to address the needs of the GSHP design community.

Kavanaugh, S.P. [Univ. of Alabama, Tuscaloosa, AL (United States)

1998-12-31

53

Effects of Seasonal Changes and Ground Ice on Electromagnetic Surveys of Permafrost.  

National Technical Information Service (NTIS)

The performance of surface impedance and magnetic induction electromagnetic subsurface exploration techniques was studied seasonally at various sites in Alaska where permafrost and massive ground ice occurred. The surface impedance method, which uses radi...

S. A. Arcone, A. J. Delaney, P. V. Sellmann

1979-01-01

54

TQWT and WDGA: innovative methods for ground roll attenuation  

NASA Astrophysics Data System (ADS)

The existence of noise in seismic data has an undesirable effect on seismic interpretations. An important type of coherent noise is ground roll, in which time and frequency overlap with useful seismic signals. The tunable Q-factor wavelet transform is a new discrete wavelet transform method and is considered as a new tool for ground roll attenuation. The simple tunable Q-factor wavelet transform by using a single wavelet with explicit oscillatory behavior is utilized for each trace. The enhanced tunable Q-factor wavelet transform (for seismic signals), which benefits from several mother wavelets with distinct Q-factors (for each part of a signal), is presented here and it is shown that it can adjust reliably to the natural non-stationary behavior of a seismic signal in time and space. Random noise has an undesirable effect on Q-factor ranges, with extreme consequences. Wavelet domain ground roll analysis is used as a substitute approach to thresholding for ground roll attenuation. The simple tunable Q-factor wavelet transform and the enhanced tunable Q-factor wavelet transform are compared with each other and with the f-k method by using synthetic and real data samples.

Goudarzi, Alireza; Riahi, Mohammad Ali

2013-12-01

55

AN A PRIORI INVESTIGATION OF ASTROPHYSICAL FALSE POSITIVES IN GROUND-BASED TRANSITING PLANET SURVEYS  

SciTech Connect

Astrophysical false positives due to stellar eclipsing binaries pose one of the greatest challenges to ground-based surveys for transiting hot Jupiters. We have used known properties of multiple star systems and hot Jupiter systems to predict, a priori, the number of such false detections and the number of genuine planet detections recovered in two hypothetical but realistic ground-based transit surveys targeting fields close to the galactic plane (b {approx} 10{sup 0}): a shallow survey covering a magnitude range 10 < V < 13 and a deep survey covering a magnitude range 15 < V < 19. Our results are consistent with the commonly reported experience of false detections outnumbering planet detections by a factor of {approx}10 in shallow surveys, while in our synthetic deep survey we find {approx}1-2 false detections for every planet detection. We characterize the eclipsing binary configurations that are most likely to cause false detections and find that they can be divided into three main types: (1) two dwarfs undergoing grazing transits, (2) two dwarfs undergoing low-latitude transits in which one component has a substantially smaller radius than the other, and (3) two eclipsing dwarfs blended with one or more physically unassociated foreground stars. We also predict that a significant fraction of hot Jupiter detections are blended with the light from other stars, showing that care must be taken to identify the presence of any unresolved neighbors in order to obtain accurate estimates of planetary radii. This issue is likely to extend to terrestrial planet candidates in the CoRoT and Kepler transit surveys, for which neighbors of much fainter relative brightness will be important.

Evans, Tom M.; Sackett, Penny D., E-mail: t.evans@physics.usyd.edu.a [Research School of Astronomy and Astrophysics, Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia)

2010-03-20

56

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

USGS Publications Warehouse

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.

Harbaugh, Arlen W.

2005-01-01

57

Ground-level ozone forecasting using data-driven methods  

Microsoft Academic Search

Accurate site-specific forecasting of hourly ground-level ozone concentrations is a key issue in air quality research nowadays\\u000a due to increase of smog pollution problem. This paper investigates three emergent data-driven methods to address the complex\\u000a nonlinear relationships between ozone and meteorological variables in Hamilton (Ontario, Canada). Three dynamic neural networks\\u000a with different structures: a time-lagged feed-forward network, a recurrent neural

T. A. Solaiman; P. Coulibaly; P. Kanaroglou

2008-01-01

58

Comparison of Creel Survey Methods on Missouri River Reservoirs  

E-print Network

Comparison of Creel Survey Methods on Missouri River Reservoirs CRAIG A. SOUPIR*1 South Dakota Game and Parks, Fort Pierre, South Dakota 57532, USA Abstract.--When creel survey methods such as noncontact indicated breakpoints in variance estimates between six and seven counts for both survey methods. Therefore

59

Survey of multi-objective optimization methods for engineering  

Microsoft Academic Search

A survey of current continuous nonlinear multi-objective optimization (MOO) concepts and methods is presented. It consolidates and relates seemingly different terminology and methods. The methods are divided into three major categories: methods with a priori articulation of preferences, methods with a posteriori articulation of preferences, and methods with no articulation of preferences. Genetic algorithms are surveyed as well. Commentary is

R. T. Marler; J. S. Arora

2004-01-01

60

Ground Truth Location Using Seismic and Satellite Imagery Methods  

NASA Astrophysics Data System (ADS)

The primary objective of this presentation is to review methods for establishing ground truth locations of industrial blasts, nuclear explosions and small magnitude earthquakes occurring in China, Indian subcontinent, Iran, North Africa and South Korea, using a synergy between the seismic and satellite imagery methods. One approach to find the ground truth locations for the industrial blasts and nuclear explosions is to apply waveform cross-correlation and master-event location technique to obtain precise relative locations of event cluster, and use the high-resolution satellite imagery to associate the clusters to observed features of the surface activities. Both nuclear explosions and industrial blasts are surface phenomena, and surface deformation caused by such events is easily identifiable on the processed satellite image. This approach has successfully identified many nuclear events in China and industrial blasts in South Korea. To establish ground truth locations of earthquakes, we look for the surface deformation caused by the events on differential interferograms processed using two satellite images, one acquired prior to and other following the occurrence of the events. Once the surface deformation associated with an earthquake is identified, the deformation field is modeled to establish the location. The depth of the seismic event is further established by separately modeling the regional and teleseismic waveform data. After establishing the epicenter from satellite data and depth from the seismogram modeling, the event location is fixed and travel-time data from all available sources are used to determine the origin time of the event. The new locations are then used to establish the source specific station corrections (SSSC) for travel times of P and S waves, which in turn, are used to relocate earthquakes occurring in their vicinity. We have successfully applied this method to earthquakes in China, Iran and North Africa. Implication of these new ground truth locations is that the events can be used to calibrate seismic travel times.

Saikia, C. K.; Fisk, M.; Myers, S.

2006-05-01

61

Development of Grounded Electrical Source Airborne Transient EM (GREATEM) Survey System and Its Application to Investigating a Volcano Structure  

NASA Astrophysics Data System (ADS)

We have developed an airborne EM system that uses a grounded electrical source and an airborne magnetic field receiver to increase the depth of investigation. Using a grounded source, we can apply a large source moment with a long transmitter-receiver distance, thus we expect to obtain a greater depth of investigation. However, the area of survey is limited with this type of method, but it has some advantages such as little effect of flight level etc. We believe that a repeated survey in active area such as volcano or fault area is effective for monitoring activity in the whole area. By using the airborne survey, we will be able to make repeated survey rapidly in volcano area where it is difficult to enter by a ground survey. The initial stage of the development was reported at Mogi et al. (1998) and the survey system was named as GREATEM (Grounded electrical source airborne transient EM). Time domain data acquisition has an advantage to the deep exploration because it avoids near source field effects that occur in frequency domain measurements. To realize the method, we should overcome mainly two problems: monitoring and filtering the motion noise of the receiver and canceling the natural magnetic field variation and cultural noise without stacking in the time domain data. We prepared high accuracy fiber optic gyros to monitor the pitch and roll of the magnetic sensor in the bird to monitor the motion and also manufactured an electromagnetic receiver that can detect three components of magnetic field and a tilt meter with MI sensor which can detect up to_ 100,000 nT with a sensitivity of 0.04 mV/nT. These receiver and tilt meter are installed on a gimbal in a bird. Data acquisition system is installed in the helicopter cabin with high precision GPS synchronized with the same type GPS set in the transmitter. In this system, we designed to analyze full wave data in time-domain for investigating deep to shallow underground resistivity structure. The measured data of three-component magnetic filed, tilting, time and positioning are digitized at 25 kHz for 10 channels. We have also developed a 3D modeling scheme to investigate magnetic field responses in the air for complicated subsurface structure and topography. We carried out GREATEM surveys at Aso Volcano, southwest Japan to test the survey system and clarify the subsurface structure of the volcano. We computed the transient response of the magnetic field in the air by removing motion noise and other EM noise using special digital filters. Finally we obtained resistivity structure, assuming horizontal layer structure. The depth of investigation of present survey was estimated about 800m deep.

Mogi, T.; Jomori, A.; Jomori, N.; Azuma, Y.; Fomenko, E. Y.

2005-12-01

62

COMPARISON OF DETECTION PROBABILITY ASSOCIATED WITH BURROWING OWL SURVEY METHODS  

E-print Network

COMPARISON OF DETECTION PROBABILITY ASSOCIATED WITH BURROWING OWL SURVEY METHODS COURTNEY J. CONWAY, grassland, monitoring, popula- tion declines, survey methods, tape playback, Wyoming. 501 Populations program is not available to quantify changes in abun- dance or distribution. Before a standardized survey

Conway, Courtney J.

63

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

NASA Technical Reports Server (NTRS)

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.

Blume, Jennifer L.

2010-01-01

64

Development of Grounded Electrical Source Airborne Transient EM (GREATEM) Survey System and Its Application to Investigating a Volcano Structure  

Microsoft Academic Search

We have developed an airborne EM system that uses a grounded electrical source and an airborne magnetic field receiver to increase the depth of investigation. Using a grounded source, we can apply a large source moment with a long transmitter-receiver distance, thus we expect to obtain a greater depth of investigation. However, the area of survey is limited with this

T. Mogi; A. Jomori; N. Jomori; Y. Azuma; E. Y. Fomenko

2005-01-01

65

Improved pipe-to-soil potential survey methods  

SciTech Connect

In 1988, the Corrosion Supervisory Committee of the Pipeline Research Committee initiated PR-186-807 titled Improved Pipe-to-Soil Potential Survey Methods.'' The primary purpose of PR-186-807 was to establish the portion of pipe sampled during a ground level pipe-to-soil potential measurement. The overall objective of this program was to improve the ability to perform and interpret close interval on- and off-potential surveys. This program included both large-scale field experiments utilizing 290 feet of 24 and 20-inch diameter pipe ranging from bare to well coated. The field measurements were primarily utilized to verify finite element analysis modeling. The modeling effort was performed to provide general statements on the area of pipe sampled as opposed to the very specific conditions present in the field measurements. This project was performed over a three year period from 1988 through 1990. The first two years examined bare pipe conditions and the third year examined coated pipe conditions. In the following sections, the results for the bare pipe and the coated pipe portions of this project are presented under separate headings.

Thompson, N.G.; Lawson, K.M.

1991-04-30

66

Assessment of some important factors affecting the singing-ground survey  

USGS Publications Warehouse

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.

Tautin, J.

1982-01-01

67

Antenna Characteristics and Air-Ground Interface Deembedding Methods for Stepped-Frequency Ground  

E-print Network

eld-tests using a Stepped-Frequency Ground Penetrating Radar (SF-GPR) and promising antenna and air-ground Penetrating Radar Measurements Brian Karlsenab, Jan Larsena, Kaj B. Jakobsenb, Helge B.D. S rensenb, Sta-metallic objects buried in the ground using a GPR. The most widely used GPRs are: the pulse radar, the Frequency

Mosegaard, Klaus

68

Eighth Conference on Health Survey Research Methods.  

National Technical Information Service (NTIS)

Contents: Foreword; Acknowledgments; Session 1: Capturing Diversity and Change in a Dynamic Population; Session 2: Community Participation and Community Benefit; Session 3: Cross-Cultural Challenges in Health Survey Research; Session 4: How to Conduct Hea...

2004-01-01

69

Ground penetrating radar surveys to locate 1918 Spanish flu victims in permafrost.  

PubMed

The "Spanish Flu" killed over 40 million people worldwide in 1918. Archival records helped us identify seven men who died of influenza in 1918 and were interred in Longyearbyen, Svalbard, Norway, 1,300 km from the North Pole. Ground Penetrating Radar (GPR) was used successfully, in a high-resolution field survey mode, to locate a large excavation with seven coffins, near the existing seven grave markers. The GPR indicated that the ground was disturbed to 2 m depth and was frozen below 1 m. Subsequent excavation showed that: a) the GPR located the position of the graves accurately, b) the coffins were buried less than 1 m deep, and c) that the frozen ground was 1.2 m deep where the coffins were located. The GPR assisted in planning the exhumation, safely and economically, under the high degree of containment required. Virologic and bacteriologic investigations on recovered tissues may give us an opportunity to isolate and identify the micro-organisms involved in the 1918 influenza and expand our knowledge on the pathogenesis of influenza. PMID:10641921

Davis, J L; Heginbottom, J A; Annan, A P; Daniels, R S; Berdal, B P; Bergan, T; Duncan, K E; Lewin, P K; Oxford, J S; Roberts, N; Skehel, J J; Smith, C R

2000-01-01

70

Deformation Analysis of Liquefied Ground by Particle Method  

NASA Astrophysics Data System (ADS)

Quantitative estimation of liquefied ground deformation has been required for performance design of foundations, embedded structures, embankments and others in recent years. This paper evaluates the applicability of MPS (Moving Particle Semi-implicit) for the estimation of liquefied ground deformation by performing simple example computation. The results suggest that MPS is potentially capable to be applied for the estimation of liquefied ground deformation.

Yoshikazu, Kobayashi

71

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

USGS Publications Warehouse

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.

Polster, Sarah W.; Drenth, Benjamin J.

2011-01-01

72

Special ground improvement methods: Ground improvements associated with the Trans?Tokyo Bay Highway  

Microsoft Academic Search

The Trans?Tokyo Bay Highway comprises the Ukishima access, two artificial islands, at Kisarazu and Kawasaki, a shield tunnel, and a bridge. The ground along the route is soft clay or loose seabed mud, so various ground improvement works had to be carried out before the construction of large?scale structures could be commenced. In this report is described how the sand

Keinosuke Uchida; Yutaka Iida; Yoshitaka Yoshida; Koji Imai

1996-01-01

73

NCES Handbook of Survey Methods: Technical Report.  

ERIC Educational Resources Information Center

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…

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

74

Statistical Methods in Surveying by Trilateration  

E-print Network

-likelihood, Monte-Carlo simulation, Trilateration, Computerized surveying, Global Positioning System (GPS) 1 #12 the implementation of fully automated real-time positioning systems similar to the global positioning system (GPS, the Global Positioning System (GPS) (Leick, 1990 Parkinson and Spilker, 1996). However, TBCC determined

Hereman, Willy A.M.

75

Combination of corrosion-survey methods improves protection  

SciTech Connect

Combining the three most widely used aboveground-survey procedures for evaluating coating integrity and cathodic protection adequacy can overcome the technical and economic penalties of choosing a single survey method. A review of each method and of several case histories shows how the procedures complement each other.

Allen, M.D.; Barnes, N.R.

1988-02-29

76

In Situ PushPull Method to Determine Ground Water Denitrification in Riparian Zones  

E-print Network

from ground water time and effort and often cannot directly explore theto soil air. In conjunction with measurements of ground water flow- removal mechanisms (i.e., plant uptake vs. microbialpaths, this method holdsIn Situ Push­Pull Method to Determine Ground Water Denitrification in Riparian Zones Kelly Addy, D

Gold, Art

77

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

NASA Astrophysics Data System (ADS)

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.

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

2000-04-01

78

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

SciTech Connect

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.

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

1991-12-01

79

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

SciTech Connect

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.

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

1991-12-01

80

Corrosion control survey methods for offshore pipelines  

SciTech Connect

Construction, operation, and maintenance of offshore pipelines and other facilities are expensive. The consequences of an offshore corrosion failure can be devastating. For these reasons, cathodic protection (CP) has become a universally applied technique for mitigating corrosion. Marine pipelines are typically provided with CP by bracelet anodes of zinc or aluminum. Impressed current systems at platforms or onshore are also used as well as hybrid systems that use a combination of the two. In this paper survey techniques are described and evaluated.

Weldon, C.P.; Kroon, D. (Corrpro Co. Inc., North, Spring, TX (US))

1992-02-01

81

SAMPLE SURVEY STATISTICS TEACHING: AN ALMOST WORLDWIDE PROBLEM ON TEACHING AGRICULTURAL SURVEY METHODS  

E-print Network

Most national or large-scale multiple-purpose Agricultural Surveys, because of their complex nature, should be based on multiple frame survey designs that use samples selected from an area frame, list frames of holdings and housing units, and point sampling methods. The problem is that, although such Agricultural Surveys imply important human and economic resources as well as time for their implementation and maintenance, the area and multiple frame survey methods already mentioned are simply not taught at most universities and statistical teaching institutions. In other words, it has been almost a worldwide tradition to teach in an inappropriate way agricultural survey methods. However those methods are widely used and involve specialized statistical knowledge for their implementation and analysis. In this paper we shall refer to the reasons of such lack of appropriate teaching as well as possible solutions.

Álvaro González Villalobos

82

A method to search for strong galaxy-galaxy lenses in optical imaging surveys  

E-print Network

We present a semi-automated method to search for strong galaxy-galaxy lenses in optical imaging surveys. Our search technique constrains the shape of strongly lensed galaxies (or arcs) in a multi-parameter space, which includes the third order (octopole) moments of objects. This method is applied to the Deep Lens Survey (DLS), a deep ground based weak lensing survey imaging to $R\\sim26$. The parameter space of arcs in the DLS is simulated using real galaxies extracted from deep HST fields in order to more accurately reproduce the properties of arcs. Arcs are detected in the DLS using a pixel thresholding method and candidate arcs are selected within this multi-parameter space. Examples of strong galaxy-galaxy lens candidates discovered in the DLS F2 field (4 square degrees) are presented.

Jeffrey M. Kubo; Ian P. Dell'Antonio

2007-12-18

83

A Survey of Methods for Planning and Analyzing Accelerated Tests  

Microsoft Academic Search

This paper surveys methods for planning and analyzing accelerated life tests. Many of these methods are new and providemore informative results for less time and cost than do previous methods. These methods are of value to all who plan and analyze accelerated tests on any product or material.

Wayne Nelson

1974-01-01

84

30 CFR 77.700-1 - Approved methods of grounding.  

...a) A solid connection to metal waterlines having low resistance to earth; (b) A solid connection to a grounding conductor, other than...no difference in potential between such metallic enclosures and the...

2014-07-01

85

30 CFR 75.700-1 - Approved methods of grounding.  

...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...between such metallic enclosures and the...

2014-07-01

86

Apparatus and method for grounding compressed fuel fueling operator  

DOEpatents

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.

Cohen, Joseph Perry (Bethlehem, PA); Farese, David John (Riegelsville, PA); Xu, Jianguo (Wrightstown, PA)

2002-06-11

87

A survey of payload integration methods  

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

88

Stability Criteria of Rubble Mounds on Soft Ground Improved via the Deep Cement Mixing Method  

Microsoft Academic Search

The construction of a rubble mound on soft ground, which was improved using the deep cement mixing method, was observed instrumentally and analyzed. To establish the design criteria for the rubble mound on the improved ground, two types of analyses of soil deformation behavior and slope stability were performed for various cases of rubble mounds on soft ground and backfills:

Young-Suk Song; Tae-Hyung Kim

2011-01-01

89

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

USGS Publications Warehouse

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.

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

1997-01-01

90

A SURVEY OF EIGENVECTOR METHODS FOR WEB INFORMATION RETRIEVAL  

E-print Network

A SURVEY OF EIGENVECTOR METHODS FOR WEB INFORMATION RETRIEVAL AMY N. LANGVILLE AND CARL D. MEYER Abstract. Web information retrieval is significantly more challenging than traditional well- controlled, small document collection information retrieval. One main difference between traditional information

Meyer, Carl

91

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

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.

Lane, R.C.

2007-01-01

92

A survey of mixed finite element methods  

NASA Technical Reports Server (NTRS)

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.

Brezzi, F.

1987-01-01

93

Ecological studies of ectomycorrhizal fungi: an analysis of survey methods  

Microsoft Academic Search

In this paper, by reviewing ecological studies of ectomycorrhizal fungi where both fruiting bodies and mycorrhizal root tips\\u000a were simultaneously surveyed, we investigate whether the diversity data obtained by the two methods leads to similar conclusions\\u000a about the underlying ecological processes of interest. Despite discrepancies in identifying species, we found that both survey\\u000a methods identified similar responses by ectomycorrhizal fungal

Beáta B. Tóth; Zoltan Barta

2010-01-01

94

The US Motor Systems Market Assessment: Baseline and Survey Methods  

E-print Network

THE US MOTOR SYSTEMS MARKET ASSESSMENT: BASELINE AND SURVEY METHODS Mitchell Rosenberg XENERGY Inc. Burlington, Massachusetts ABSTRACT This paper summarizes the current status of the US Motor Systems Market Assessment. This component...THE US MOTOR SYSTEMS MARKET ASSESSMENT: BASELINE AND SURVEY METHODS Mitchell Rosenberg XENERGY Inc. Burlington, Massachusetts ABSTRACT This paper summarizes the current status of the US Motor Systems Market Assessment. This component...

Rosenberg, M.

95

Evaluation of estimation method of ground properties for the ground source heat pump system  

Microsoft Academic Search

Technology directed at geothermal energy, one of our renewable energy sources, to heat and air-condition buildings has become very attractive in recent years following the significant developments in ground-source heat pump (GSHP) systems. In general, although the energy efficiency of GSHP systems is far superior to conventional air-source heat pump (ASHP) systems, GSHP system is still expensive. Therefore, GSHP system

Suckho Hwang; Ryozo Ooka; Yujin Nam

2010-01-01

96

Verifying a computational method for predicting extreme ground motion  

USGS Publications Warehouse

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.

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

97

Overlapping Community Discovery Methods: A Survey  

E-print Network

The detection of overlapping communities is a challenging problem which is gaining increasing interest in recent years because of the natural attitude of individuals, observed in real-world networks, to participate in multiple groups at the same time. This review gives a description of the main proposals in the field. Besides the methods designed for static networks, some new approaches that deal with the detection of overlapping communities in networks that change over time, are described. Methods are classified with respect to the underlying principles guiding them to obtain a network division in groups sharing part of their nodes. For each of them we also report, when available, computational complexity and web site address from which it is possible to download the software implementing the method.

Amelio, Alessia

2014-01-01

98

Evaluation of aerial survey methods for Dall's sheep  

USGS Publications Warehouse

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.

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

2006-01-01

99

New Technologies for Soft Ground Improvement in Japan ? Low Improvement Ratio Cement Column Method and Lightweight Banking Method  

Microsoft Academic Search

This paper presents promising new technologies for soft ground improvement which include the low improvement ratio cement column method (LCC) and the lightweight banking method using foam mixed soil (LFS). As a measure to reduce settlement and lateral deformation due to road embankment loading on soft ground, the column type deep mixing method used at a low improvement ratio of

H. Miki

100

A survey of modern authorship attribution methods  

Microsoft Academic Search

Authorship attribution supported by statistical or computational methods has a long history starting from 19th century and marked by the seminal study of Mosteller and Wallace (1964) on the authorship of the disputed Federalist Papers. During the last decade, this scientific field has been developed substantially taking advantage of research advances in areas such as machine learning, information retrieval, and

Efstathios Stamatatos

2009-01-01

101

Digital certificates: a survey of revocation methods  

Microsoft Academic Search

Digital certificates form a basis that allows entities to trust each other. Due to different constraints, a certificate is only valid within a specific period of time. Coming from several threats, there are important reasons why its validity must be terminated sooner than assigned and thus, the certificate needs to be revoked. This paper provides a classification of revocation methods

Petra Wohlmacher

2000-01-01

102

A Survey of Quantum Lyapunov Control Methods  

PubMed Central

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

2013-01-01

103

The National Criminal Justice Treatment Practices survey: Multilevel survey methods and procedures?  

PubMed Central

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

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

2007-01-01

104

Grounded action research: a method for understanding IT in practice  

Microsoft Academic Search

This paper shows how the theory development portion of action research can be made more rigorous. The process of theory formulation is an essential part of action research, yet this process is not well understood. A case study demonstrates how units of analysis and techniques from grounded theory can be integrated into the action research cycle in order to add

Richard Baskerville; Jan Pries-Heje

1999-01-01

105

[Historical survey of modern reversible contraceptive methods].  

PubMed

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 were flexible and capable of returning to their original shape after insertion. The Lippes loop was the 1st highly successful IUD. Bioactive IUDs containing copper were developed in the 1970s. Research is underway to develop IUDs which will resist expulsion, reduce bleeding, be more appropriate for multiparas, and last longer. IUDs are used to treat intrauterine adhesions as well as for contraception. A gummy substance used to block the cervix was described in Egypt in 1850 BC. Japanese and Chinese prostitutes of antiquity placed oiled bamboo paper at the cervical opening for contraception. Diaphragms and cervical caps were developed in the 19th century in Germany. Large scale production became possible after 1880 with the development of better, more durable, and cheaper rubber. An Egyptian writing in 3500 BC began the study of spermicides. Numerous substances such as lemon juice and honey have been placed in the vagina to avoid pregnancy. Such substances are available to all women and some were reasonably effective. Current research is directed toward development of spermicides which will also prevent sexually transmitted diseases. The 1st condoms were made of animal skins by an English physician to prevent transmission of venereal diseases. Rubber condoms appeared in the early 20th century and are widely utilized in some family planning programs. Pregnancy vaccines and a reversible hormonal method for men are among methods under development. PMID:12268230

Mbabajende, V

1986-04-01

106

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

USGS Publications Warehouse

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.

Anthony, Stephen S.

1997-01-01

107

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

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

108

Checklist and Pollard Walk butterfly survey methods on public lands  

USGS Publications Warehouse

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.

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

1998-01-01

109

SURVEY ON VARIOUS INTERPOLATION BASED FUZZY REASONING METHODS  

Microsoft Academic Search

Approximate fuzzy reasoning methods serves the task of inference in case of fuzzy systems built on sparse rule bases. This paper is a part of a longer survey that aims to provide a qualitative view through the various ideas and characteristics of interpolation based fuzzy reasoning methods. It also aims to define a general condition set for fuzzy rule interpolation

ZSOLT CSABA JOHANYÁK; SZILVESZTER KOVÁCS

2006-01-01

110

A European food consumption survey method–conclusions and recommendations  

Microsoft Academic Search

Objective: To discuss the general outcome and conclusions of a European project (EFCOSUM); to develop a method for a European food consumption survey that delivers internationally comparable data on a set of policy relevant nutritional indicators.Design and methods: The EFCOSUM project was carried out within the framework of the European Health Monitoring Programme by 14 Member States as well as

JH Brussaard; MRH Löwik; L Steingrímsdóttir; A Møller; J Kearney; S De Henauw; W Becker

2002-01-01

111

Formulation and survey of ALE method in nonlinear solid mechanics  

Microsoft Academic Search

This paper investigates the applicability and accuracy of existing formulation methods in general purpose finite element programs to the finite strain deformation problems. The basic shortcomings in using such programs in these applications are then pointed out and the need for a different type of formulation is discussed. An arbitrary Lagrangian-Eulerian (ALE) method is proposed and a concise survey of

J. Wang; M. S. Gadala

1997-01-01

112

A Novel Method of Enhancing Grounded Theory Memos with Voice Recording  

ERIC Educational Resources Information Center

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…

Stocker, Rachel; Close, Helen

2013-01-01

113

THE HYBRID EMPIRICAL METHOD AND ITS USE IN PREDICTIONG STRONG GROUND MOTION IN EUROPE  

Microsoft Academic Search

SUMMARY Ground motion models (attenuation relationships) are used to estimate strong ground motion for many engineering and seismological applications. Where strong-motion recordings are abundant, these models are developed empirically from these recordings. Where strong-motion recordings are sparse, they are often developed from seismological models using the Stochastic or Theoretical Methods. Although use of these latter methods has become common place,

Kenneth W. CAMPBELL

2006-01-01

114

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

USGS Publications Warehouse

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.

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

2006-01-01

115

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

PubMed

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

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

2011-06-01

116

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...

117

Optimal Filtering Methods to Structural Damage Estimation under Ground Excitation  

PubMed Central

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

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

2013-01-01

118

Detailed analysis of the geomagnetic ground survey performed in middle-northern Croatia over the time interval 2003–2005  

Microsoft Academic Search

During the time interval 2003–2005 a ground survey of the total magnetic field intensity in the middle-northern part of Croatia\\u000a was performed, in order to get a detailed insight of the field distribution over the region. A special effort was done to\\u000a understand the uncertainty and errors in data reduction, namely different amplitudes of the diurnal variations and different\\u000a secular

Eugen Vujic; Giuliana Verbanac; Vladis Vujnovic; Antun Marki

2009-01-01

119

Above-ground Forest Biomass Estimation by ALOS/PALSAR over Boreal Forest in Alaska Accompanied with Ground-based Forest Survey  

NASA Astrophysics Data System (ADS)

For the better understanding of the carbon cycle in the global ecosystem, investigations on the spatio-temporal variation of the carbon stock which is stored as vegetation biomass is important. The L-band microwave radar “PALSAR (Phased Array type L-band Synthetic Aperture Radar)” of the satellite “ALOS (Advanced Land Observing Satellite)” provides the information which can be used for the above-ground forest biomass (AGFB) estimation. An attempt to map the AGFB distribution over an ecotone region in Alaska was carried out based on ALOS/PALSAR data. In July 2007, a ground-based forest survey was executed in the south-north transect (about 500 km long) along a trans-Alaska pipeline which profiles the ecotone from boreal forest to tundra in Alaska. 29 forests along the transect were targeted for the survey, and their AGFB were measured. Consequently, it was revealed that the AGFB ranges from 5 to 100 ton/ha (dried matter). These ground-based AGFB measurements at 29 forests were compared with the signal (digital number) in 20 scenes of ALOS/PALSAR (HV polarization mode) that cover the 29 forests in July or August 2007. In addition, 16 areas of grassland in the images were picked for the reference value of the zero AGFB. The result showed a positive strong (r = 0.84) and linear relationship between them, demonstrating a feasibility of ALOS/PALSAR for the mapping of the AGFB. Based on the linear relationship, the AGFB was estimated and mapped over the ecotone region in Alaska. Generally, there is a south to north gradient in AGFB that reflects the AGFB gradient from southern forest-rich region to northern forest-sparse region in the ecotone. The AGFB in some regions in southern part reaches 100 Mg/ha.

Suzuki, R.; Kim, Y.; Ishii, R.; Nicoll, J.

2009-12-01

120

Ground Motion Simulation Using the Hybrid Empirical Method: Issues and Insights  

Microsoft Academic Search

\\u000a The widespread application of the hybrid empirical method (HEM) has made it a viable approach for developing ground motion\\u000a prediction equations (GMPEs) in regions where there are few strong motion recordings but ample weak motion data from small-to-moderate\\u000a magnitude earthquakes. The HEM uses empirical estimates of ground motion in a host region\\u000a to provide estimates of ground motion in a

K. W. Campbell

121

An aerial survey method to estimate sea otter abundance  

USGS Publications Warehouse

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.

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

1999-01-01

122

Integrated resistivity surveys for delineation of fractures for ground water exploration in hard rock areas  

Microsoft Academic Search

Acute shortage of ground water in hard rock areas is well known. Ground water occurs in limited areal extent in secondary porosity generally developed due to weathering, fracturing, jointing, faulting etc. within the hard rock formations. These structural changes (fractures etc.) are sparsely distributed in the hard rock areas. Gradient profiling followed by geoelectrical sounding has been successfully utilized to

G. S. Yadav; Shashi Kant Singh

2007-01-01

123

Ground penetrating radar survey of the ice-filled active crater of Mount Baker, Washington  

NASA Astrophysics Data System (ADS)

Sherman Crater, the center of volcanic activity at Mount Baker, in northwest Washington, provides an excellent site to study glacier dynamics in an active crater because of its history of sudden, significant increases in geothermal activity, its confined geometry, the potential hazards it poses to downstream reservoirs, and the paucity of recent research related to these hazards. We present results from a ground penetrating radar (GPR) survey of the crater conducted in the summers of 2009 and 2010, including characterization of the subglacial crater morphology, estimates for the crater glacier’s volume, maximum depth, annual mass balance and surface velocity and for the crater’s geothermal flux density. We used a GSSI SIR-3000 GPR system and a low frequency (80 MHz) antenna in common-offset (reflection) collection mode to image subglacial conditions along several west-east and south-north transects within the crater. We processed the GPR data with GSSI’s RADAN 6.0 and paired the surface elevations of each transect to the ice-surface topography using GPS locations and spot altimeter readings. GPR profiles reveal several sets of distinct basal and englacial reflectors. Along west-east (longitudinal) transects, the crater’s bedrock topography largely follows the glacier’s surface (high to the west, descending to the east), but the ice thins dramatically along the margin nearest the crater rim’s eastern breach. The prominent basal reflectors in the GPR transects are consistent with an ice/hydrothermally altered rock interface, but short more well-defined segments suggest the presence of bedrock (towards the center of the crater) and water (near the eastern breach) at the base of the ice. GPR data combined with surface ice melting measurements yield a first-order estimate for the area-averaged accumulation rate of 4.8 +/- 0.1 m yr-1 and ablation rate of 2.4 +/- 0.3 m yr-1 water equivalent from surface melting. The resulting calculated geothermal flux for Sherman Crater of ~20 Wm-2 is consistent with published calculations for active calderas (Mt. Veniaminof) and volcanic lakes. We estimate the maximum ice thickness to be ~50 m, and the ice velocity to range from ~3 to 4 m/month during the summer months. Highest surface ice velocities are found on moderate slopes above the deepest part of the crater, where the ice is thickest (inferred from GPR profiles).

Park, M.; Clark, D. H.; Caplan-Auerbach, J.

2010-12-01

124

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

NASA Technical Reports Server (NTRS)

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.

Kuhn, R. E.; Eshleman, J.

1985-01-01

125

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

NASA Technical Reports Server (NTRS)

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.

Eshlemen, J.; Kuhn, R. E.

1985-01-01

126

A Ground Truthing Method for AVIRIS Overflights Using Canopy Absorption Spectra  

NASA Technical Reports Server (NTRS)

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).

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

1996-01-01

127

Comparison of Estimation Methods for Complex Survey Data Analysis  

Microsoft Academic Search

Abstract Recently structural equation modeling software packages have implemented more accurate statistical methodology for analyzing complex survey data. The computa- tional algorithms however vary across the packages and produce dierent,results even for simple models. In this note we conduct simulation studies to compare the per- formance of the methods implemented in Mplus and LISREL. The Mplus algorithm produced more accurate

Tihomir Asparouhov; Bengt Muthen

128

A survey on statistical methods for health care fraud detection  

E-print Network

Media, LLC 2007 Abstract Fraud and abuse have led to significant addition- al expense in the health careA survey on statistical methods for health care fraud detection Jing Li & Kuei-Ying Huang applied to health care fraud detection, with focuses on classifying fraudulent behaviors, identify- ing

Li, Jing

129

A SURVEY OF EIGENVECTOR METHODS FOR WEB INFORMATION RETRIEVAL #  

E-print Network

A SURVEY OF EIGENVECTOR METHODS FOR WEB INFORMATION RETRIEVAL # AMY N. LANGVILLE + AND CARL D. MEYER # Abstract. Web information retrieval is significantly more challenging than traditional well­ controlled, small document collection information retrieval. One main di#erence between traditional

Meyer, Carl

130

A Survey of Methods for Pure Nonlinear Integer Programming  

Microsoft Academic Search

The subject of this paper is a classification and discussion of algorithms for solution of nonlinear pure integer programming problems. The survey is organized by characterizing the mathematical form of the nonlinear optimization problems addressed by the various algorithms. If any method can be used without changes to solve mixed integer nonlinear programming problems that fact is mentioned in the

Mary W. Cooper

1981-01-01

131

Quantum Monte Carlo method for the ground state of many-boson systems  

Microsoft Academic Search

We formulate a quantum Monte Carlo (QMC) method for calculating the ground state of many-boson systems. The method is based on a field-theoretical approach, and is closely related to existing fermion auxiliary-field QMC methods which are applied in several fields of physics. The ground-state projection is implemented as a branching random walk in the space of permanents consisting of identical

Wirawan Purwanto; Shiwei Zhang

2004-01-01

132

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

ERIC Educational Resources Information Center

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…

Babchuk, Wayne A.

2011-01-01

133

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

ERIC Educational Resources Information Center

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…

Jacob, Robin Tepper; Jacob, Brian

2012-01-01

134

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

NASA Technical Reports Server (NTRS)

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.

1981-01-01

135

method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings Skol  

EPA Pesticide Factsheets

Search instead for method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings Skol ?

136

Ground and marine magnetic surveys of the lower eastern flank of Etna volcano (Italy)  

Microsoft Academic Search

In 1996 and 1997, two high-resolution magnetic surveys, one on land and the other at sea, were carried out on the lower eastern flank of Mount Etna. The magnetic surveys, covering an area of about 400 km2, aimed to elucidate the relationships between the main tectonic and morphologic features of this flank of Mount Etna. Major features include widespread NNW-

Ciro Del Negro; Rosalba Napoli

2002-01-01

137

Survey of aircraft subcritical flight flutter testing methods  

NASA Technical Reports Server (NTRS)

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.

Rosenbaum, R.

1974-01-01

138

USGS Ground-Water Techniques, Methods, and Models  

NSDL National Science Digital Library

This USGS site offers a collection of documents and resources about groundwater data collection methods and groundwater modeling. The site includes several references for field methods and techniques, including well installation, sample collection, geophysical tools, and the collection of water use data. Groundwater modeling topics cover MODFLOW, HYMOD, SEAWAT, WTAQ, and MOC3D. There is also a link to an index of many groundwater modeling software programs.

Usgs

139

Mixing Web and Mail Methods in a Survey of Physicians  

PubMed Central

Objective To assess the effects of two different mixed-mode (mail and web survey) combinations on response rates, response times, and nonresponse bias in a sample of primary care and specialty internal medicine physicians. Data Sources/Study Setting Primary data were collected from 500 physicians with an appointment in the Mayo Clinic Department of Medicine (DOM) between February and March 2005. Study Design Physicians were randomly assigned to receive either an initial mailed survey evaluating the Electronic Medical Record (EMR) with a web survey follow-up to nonrespondents or its converse—an initial web survey followed by a mailed survey to nonrespondents. Response rates for each condition were calculated using standard formula. Response times were determined as well. Nonresponse bias was measured by comparing selected characteristics of survey respondents to similar characteristics in the full sample frame. In addition, the distributions of results on key outcome variables were compared overall and by data collection condition and phase. Principal Findings Overall response rates were somewhat higher in the mail/web condition (70.5 percent) than in the web/mail condition (62.9 percent); differences were more pronounced before the mode switch prior to the mailing to nonrespondents. Median response time was 2 days faster in the web/mail condition than in the mail/web (median=5 and 7 days, respectively) but there was evidence of under-representation of specialist physicians and those who used the EMR a half a day or less each day in the web/mail condition before introduction of the mailed component. This did not translate into significant inconsistencies or differences in the distributions of key outcome variables, however. Conclusions A methodology that uses an initial mailing of a self-administered form followed by a web survey to nonrespondents provides slightly higher response rates and a more representative sample than one that starts with web and ends with a mailed survey. However, if the length of the data collection period is limited and rapid response is important, perhaps the web survey followed by a mailed questionnaire is to be preferred. Key outcome variables appear to be unaffected by the data collection method. PMID:17489911

Beebe, Timothy J; Locke, G Richard; Barnes, Sunni A; Davern, Michael E; Anderson, Kari J

2007-01-01

140

Input impedance calculation of vertical wire antennas above lossy ground using matrix pencil method  

Microsoft Academic Search

A method for evaluation of impedance and current distribution of vertical wire antennas above lossy ground is presented. Simulation is performed for several frequencies and the electrical parameter of soil. The results are compared with those of other methods showing the accuracy of our developed routine. In this paper we use Pocklington's integral equation and we use the method of

Ali Khalatpour; Reza Saraf; Gholamreza Moradi

2009-01-01

141

Novel Identification Method of Stator Single Phase-to-Ground Fault for Cable-Wound Generators  

Microsoft Academic Search

A new criterion to detect the stator single phase-to-ground fault for Powerformer is proposed in this paper, which is based on the direction of zero-sequence compositive power flow. By virtue of the analysis of new fault characteristics of Powerformer and the comparison with conventional methods, a novel identification scheme is put forward. The proposed approach detects the ground fault by

Yan Gao; Xiangning Lin; Qing Tian; Pei Liu

2008-01-01

142

REVIEWS OF TOPICAL PROBLEMS: Sky surveys and deep fields of ground-based and space telescopes  

NASA Astrophysics Data System (ADS)

Selected results obtained in major observational sky surveys (DSS, 2MASS, 2dF, SDSS) and deep field observations (HDF, GOODS, UHDF, etc.) are reviewed. Modern surveys provide information on the characteristics and space distribution of millions of galaxies. Deep fields allow one to study galaxies at the stage of formation and to trace their evolution over billions of years. The wealth of observational data is altering the face of modern astronomy: the formulation of problems and their solutions are changing and all the previous knowledge, from planetary studies in the solar system to the most distant galaxies and quasars, is being revised.

Reshetnikov, Vladimir P.

2005-11-01

143

Survey methods and results at: www.umass.edu/oapa/oapa/reports/senior_survey. Office of Academic Planning and Assessment, 11/20/2013 2013 UMass-Amherst Graduating Senior Survey  

E-print Network

Survey methods and results at: www.umass.edu/oapa/oapa/reports/senior_survey. Office of Academic. Survey methods and results at: www.umass.edu/oapa/oapa/reports/senior_survey. Office of Academic Planning

Massachusetts at Amherst, University of

144

Survey and Method for Determination of Trajectory Predictor Requirements  

NASA Technical Reports Server (NTRS)

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

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

2009-01-01

145

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

NASA Astrophysics Data System (ADS)

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.

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

2014-12-01

146

Three-dimensional resistivity modelling of grounded electrical-source airborne transient electromagnetic (GREATEM) survey data from the Nojima Fault, Awaji Island, south-east Japan  

NASA Astrophysics Data System (ADS)

An airborne electromagnetic (AEM) survey using the grounded electrical-source airborne transient electromagnetic (GREATEM) system was conducted over the Nojima Fault on Awaji Island, south-east Japan, to assess GREATEM survey applicability for studying coastal areas with complex topographic features. To obtain high-quality data with an optimised signal-to-noise ratio, a series of data processing techniques was used to acquire the final transient response curves from the field survey data. The 1D inversion results were feasible in that the horizontal resistivity contrast was not much higher than the true contrast, but they were not reasonable in that the horizontal resistivity values were greatly changed. To circumvent this problem, we performed numerical forward modelling using a finite-difference staggered-grid method (Fomenko and Mogi, 2002) adding a finite-length electrical dipole source routine to generate a three-dimensional (3D) resistivity structure model from GREATEM survey data of the Nojima Fault area. The 3D model was based on an initial model consisting of two adjacent onshore and offshore layers of different conductivity such that, a highly conductive sea of depth (10-40 m) is placed on top of a uniform half-space, assuming the presence of topographic features on the inland side. We examined the fit of the magnetic transient responses between field data and 3D forward-model computed data, the latter were convolved with the measured system response of the corresponding dataset. The inverted 3D resistivity structures showed that the GREATEM system has the capability to map underground resistivity structures as deep as 500 m onshore and offshore. The GREATEM survey delineated how seawater intrudes on the landside of the fault and indicated that the fault is a barrier to seawater invasion.

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

2014-08-01

147

A simplified analysis method for piled raft foundations subjected to ground movements induced by tunnelling  

Microsoft Academic Search

A simplified method of numerical analysis has been developed to estimate the deformation and load distribution of piled raft foundations subjected to ground movements induced by tunnelling and incorporated into a computer program PRAB. In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates, the piles as elastic beams, and the soil

Pastsakorn Kitiyodom; Tatsunori Matsumoto; Kanji Kawaguchi

2005-01-01

148

WAVEFRONT RECONSTRUCTION METHODS FOR ADAPTIVE OPTICS SYSTEMS ON GROUND-BASED TELESCOPES  

E-print Network

WAVEFRONT RECONSTRUCTION METHODS FOR ADAPTIVE OPTICS SYSTEMS ON GROUND-BASED TELESCOPES JOHNATHAN M the refractive blurring of images. Adaptive optics systems seek to remove phase error from incoming wavefronts methods, and comparisons are made. Keywords: adaptive optics, wavefront reconstruction, minimum variance

Bardsley, John

149

Analysis of vertical wire antenna above imperfect ground using discrete complex image method  

Microsoft Academic Search

A simple and almost exact image method is proposed for the analysis of vertical thin-wire antennas above lossy ground. This method is based on the replacement of the lossy half-space by a few complex images. The GPOF technique and Sommerfeld integral equation are used to find the location and intensity of the current images. Similar to dipole sources, a few

Mohammad Hakkak; Bijan Abbasi Arand

2002-01-01

150

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

ERIC Educational Resources Information Center

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…

Kinnunen, Paivi; Simon, Beth

2012-01-01

151

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

ERIC Educational Resources Information Center

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…

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

2005-01-01

152

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

NASA Technical Reports Server (NTRS)

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.

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

153

THE IMACS CLUSTER BUILDING SURVEY. I. DESCRIPTION OF THE SURVEY AND ANALYSIS METHODS  

SciTech Connect

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.

Oemler, Augustus Jr.; Dressler, Alan; Kelson, Daniel; Villanueva, Edward [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101-1292 (United States); Gladders, Michael G. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Rigby, Jane R. [Observational Cosmology Lab, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bai Lei [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Fritz, Jacopo [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Rieke, George [Steward Observatory, University of Arizona, Tucson, AZ 8572 (United States); Poggianti, Bianca M.; Vulcani, Benedetta, E-mail: oemler@obs.carnegiescience.edu [INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy)

2013-06-10

154

A new method of combination of electroosmosis, vacuum and surcharge preloading for soft ground improvement  

NASA Astrophysics Data System (ADS)

As a rapid and effective ground improvement method is urgently required for the booming land reclamation in China's coastal area, this study proposes a new combined method of electroosmosis, vacuum preloading and surcharge preloading. A new type of electrical prefabricated vertical drain (ePVD) and a new electroosmotic drainage system are suggested to allow the application of the new method. This combined method is then field-tested and compared with the conventional vacuum combined with surcharge preloading method. The monitoring and foundation test results show that the new method induces a settlement 20% larger than that of the conventional vacuum combined with surcharge preloading method in the same treatment period, and saves approximately half of the treatment time compared with the vacuum combined with surcharge preloading method according to the finite element prediction of the settlement. The proposed method also increases the vane shear strength of the soil significantly. The bearing capacity of the ground improved by use of the new proposed method raises 118%. In comparison, there is only a 75% rise when using the vacuum combined with surcharge preloading method during the same reinforcement period. All results indicate that the proposed combined method is effective and suitable for reinforcing the soft clay ground. Besides, the voltage applied between the anode and cathode increases exponentially versus treatment time when the output current of power supplies is kept constant. Most of the voltage potential in electroosmosis is lost at electrodes, leaving smaller than 50% of the voltage to be effectively transmitted into the soil.

Liu, Han-long; Cui, Yun-liang; Shen, Yang; Ding, Xuan-ming

2014-08-01

155

Health-Based Screening Levels to Evaluate U.S. Geological Survey Ground water Quality Data  

Microsoft Academic Search

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

Patricia L. Toccalino; Julia E. Norman

2006-01-01

156

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

NASA Astrophysics Data System (ADS)

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.

Wang, Hanquan

2014-10-01

157

Ground and marine magnetic surveys of the lower eastern flank of Etna volcano (Italy)  

NASA Astrophysics Data System (ADS)

In 1996 and 1997, two high-resolution magnetic surveys, one on land and the other at sea, were carried out on the lower eastern flank of Mount Etna. The magnetic surveys, covering an area of about 400 km 2, aimed to elucidate the relationships between the main tectonic and morphologic features of this flank of Mount Etna. Major features include widespread NNW- and NNE-trending active faults and the Valle del Bove, a depression considered to be the source area of the Chiancone deposit, the largest Etnean volcaniclastic sequence. Magnetic surveys show anomalies that roughly follow the trend of active main structures. Although few magnetization measurements are available for the most representative outcrops of the lower eastern side of Mount Etna, interpretation of the anomalies defines the underground geometry of the Chiancone deposit and its relationship with volcano stratigraphic units and the underlying sedimentary rocks. In particular, a volume of about 14 km 3 was ascribed to the Chiancone deposit. Such a large amount of material was likely produced by a catastrophic event, and deposited at different periods at the exit of the Valle del Bove in an area produced by the interaction, on a regional scale, of the main tectonic structures affecting this flank of the volcano.

Del Negro, Ciro; Napoli, Rosalba

2002-05-01

158

Auxilliary Method Or Sophisticated Field Method? - Thoughts On The Use of Large Scale Magnetometer Surveying In Archaeology  

Microsoft Academic Search

The contribution presents large scale magnetometer surveys at early neolithic sites (Linearbandkeramik, 5500-4900 B.C.) in Germany. They serve to supply a prospect for future use of magnetometer survey in archaeological research. It is claimed that it ought to be a major goal to make geophysical survey and magnetometer survey espe- cially an independent field method in archaeology becoming used with

M. Posselt

2002-01-01

159

Survey of hyperspectral image denoising methods based on tensor decompositions  

NASA Astrophysics Data System (ADS)

A hyperspectral image (HSI) is always modeled as a three-dimensional tensor, with the first two dimensions indicating the spatial domain and the third dimension indicating the spectral domain. The classical matrix-based denoising methods require to rearrange the tensor into a matrix, then filter noise in the column space, and finally rebuild the tensor. To avoid the rearranging and rebuilding steps, the tensor-based denoising methods can be used to process the HSI directly by employing multilinear algebra. This paper presents a survey on three newly proposed HSI denoising methods and shows their performances in reducing noise. The first method is the Multiway Wiener Filter (MWF), which is an extension of the Wiener filter to data tensors, based on the TUCKER3 decomposition. The second one is the PARAFAC filter, which removes noise by truncating the lower rank K of the PARAFAC decomposition. And the third one is the combination of multidimensional wavelet packet transform (MWPT) and MWF (MWPT-MWF), which models each coefficient set as a tensor and then filters each tensor by applying MWF. MWPT-MWF has been proposed to preserve rare signals in the denoising process, which cannot be preserved well by using the MWF or PARAFAC filters. A real-world HYDICE HSI data is used in the experiments to assess these three tensor-based denoising methods, and the performances of each method are analyzed in two aspects: signal-to-noise ratio and improvement of subsequent target detection results.

Lin, Tao; Bourennane, Salah

2013-12-01

160

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

DOEpatents

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.

Andrews, L.B.

1998-08-18

161

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

NASA Technical Reports Server (NTRS)

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.

Trible, M. C.

1972-01-01

162

Using Survey Methods for Design and Evaluation in Child Computer Interaction  

E-print Network

This paper begins with a review of some of the current literature on the use of survey methods with children. It then presents four known concerns with using survey methods and reflects on how these may impact on studies in Child Computer Interaction. The paper presents some guidelines for HCI researchers and developers intending to use survey methods in their studies with children, and closes with some thoughts about the use of survey methods in this interesting but complex area.

Janet Read

163

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

NASA Astrophysics Data System (ADS)

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.

Sandal, Gro Mjeldheim; Manzey, Dietrich

164

Medical economics survey-methods study: cost-effectiveness of alternative survey strategies.  

PubMed

The Medical Economics Survey-Methods Study was conducted under contract for the National Center for Health Statistics during 1975-76. The objective was to determine the cost-effectiveness of a variety of strategies under consideration for application in a national survey in 1977. Detailed data on health care utilization and expenditures were collected periodically from a panel of 691 Maryland households over a seven-month period. Issues tested through a random experimental design included the relative effectiveness of monthly versus bimonthly interviews and in-person versus telephone contact. Completeness and accuracy of information were determined through an extensive record check involving all providers and third party payers identified in the household check involving all providers and third party payers identified in the household survey. The results indicate that there are substantial deficiencies in the household reporting and that the household data for all types of medical services would benefit from the availability of record data in order to improve theri accuracy. The frequency of contact (monthly versus bimonthly) had little effect on the accuracy of reporting. Given the higher rate of attrition observed for the monthly procedures and their considerably greater cost, the bimonthly interval appears to offer advantages. In-person contact resulted in significantly better reporting compared with telephone contact in the Baltimore area, but no difference was found in more rural Washington County. Thus, the 10 per cent cost increase for in-person contact may well be justified by the improved accuracy of the data obtained for certain types of populations. PMID:97474

Yaffe, R; Shapiro, S; Fuchseberg, R R; Rohde, C A; Corpeno, H C

1978-08-01

165

Using Survey Methods for Design and Evaluation in Child Computer Interaction  

E-print Network

Using Survey Methods for Design and Evaluation in Child Computer Interaction Janet Read Child@aol.com ABSTRACT This paper begins with a review of some of the current literature on the use of survey methods with children. It then presents four known concerns with using survey methods and reflects on how these may

166

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)

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).

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

2013-12-01

167

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...

168

A simplified analysis method for piled raft foundations subjected to ground movements induced by tunnelling  

NASA Astrophysics Data System (ADS)

A simplified method of numerical analysis has been developed to estimate the deformation and load distribution of piled raft foundations subjected to ground movements induced by tunnelling and incorporated into a computer program PRAB. In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates, the piles as elastic beams, and the soil is treated as interactive springs. The interactions between structural members, pile-soil-pile, pile-soil-raft and raft-soil-raft interactions, are modelled based on Mindlin's solutions for both vertical and lateral forces. The validity of the proposed method is verified through comparisons with some published solutions for single piles and pile groups subjected to ground movements induced by tunnelling. Thereafter, the solutions from this approach for the analysis of a pile group and a piled raft subjected to ground movements induced by tunnelling are compared with those from three-dimensional finite difference program. Good agreements between these solutions are demonstrated. The method is then used for a parametric study of single piles, pile groups and piled rafts subjected to ground movements induced by tunnelling. Copyright

Kitiyodom, Pastsakorn; Matsumoto, Tatsunori; Kawaguchi, Kanji

2005-12-01

169

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

ERIC Educational Resources Information Center

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…

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

2012-01-01

170

Simulation of cylindrical flow to a well using the U. S. geological survey modular finite-difference ground-water flow model  

Microsoft Academic Search

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 US Geological Survey Modular Three-Dimensional Finite-Difference Ground-Water Flow Model provides the opportunity to simulate axisymmetric flow to a well.

T. E. Reilly; A. W. Harbaugh

2009-01-01

171

Ground-based infrared surveys: imaging the thermal fields at volcanoes and revealing the controlling parameters.  

NASA Astrophysics Data System (ADS)

Temperature monitoring is a widespread procedure in the frame of volcano hazard monitoring. Indeed temperature changes are expected to reflect changes in volcanic activity. We propose a new approach, within the thermal monitoring, which is meant to shed light on the parameters controlling the fluid pathways and the fumarole sites by using infrared measurements. Ground-based infrared cameras allow one to remotely image the spatial distribution, geometric pattern and amplitude of fumarole fields on volcanoes at metre to centimetre resolution. Infrared mosaics and time series are generated and interpreted, by integrating geological field observations and modeling, to define the setting of the volcanic degassing system at shallow level. We present results for different volcano morphologies and show that lithology, structures and topography control the appearance of fumarole field by the creation of permeability contrasts. We also show that the relative importance of those parameters is site-dependent. Deciphering the setting of the degassing system is essential for hazard assessment studies because it would improve our understanding on how the system responds to endogenous or exogenous modification.

Pantaleo, Michele; Walter, Thomas

2013-04-01

172

A Method for Emphasizing Reflection Waves from Buried Objects by Using Ground-penetrating Radar  

NASA Astrophysics Data System (ADS)

Ground-penetrating radar (GPR) is a useful tool for performing subsurface imaging by using radar pulses. In previous paper, we proposed a method for denoising GPR signals by using 2D Gabor wavelet transforms. In this paper, we present a new method for emphasizing GPR reflected waves from buried objects. We can evaluate the results of the time-frequency analysis of the reflection waves on the basis of the Markov Chain Monte Carlo (MCMC) and the Infinite Gaussian Mixture Model (IGMM) methods. Our proposed methods are effective as pre-processing method for detecting the positions of buried metal pipes.

Kobayashi, Makoto; Nakano, Kazushi

173

IEEE COMMUNICATIONS SURVEYS & TUTORIALS, VOL. 12, NO. 2, SECOND QUARTER 2010 1 A Survey on Methods for Broadband Internet  

E-print Network

likely to use trains than cars or airplanes if Wi-Fi access was available on trains. This study also found that 78% of these business travelers would use Wi-Fi access if it was made available on trains [1IEEE COMMUNICATIONS SURVEYS & TUTORIALS, VOL. 12, NO. 2, SECOND QUARTER 2010 1 A Survey on Methods

Kansas, University of

174

Estimation of ground and excited state dipole moments of Oil Red O by solvatochromic shift methods.  

PubMed

Absorption and fluorescence spectra of Oil Red O (abbreviated as ORO) are recorded in various solvents with different polarity in the range of 250-900 nm, at room temperature. The solvatochromic shift methods have been used to determine the ground state (?g) and excited state (?e) dipole moments depending on dielectric constant and refractive index functions. It is observed that fluorescence spectra show positive solvatochromism whereas absorption spectra do not indicates sensitive behavior to solvent polarity. Excited state dipole moment is found as higher than those of ground state for all of the used methods and it is attributed to more polar excited state of ORO. Theoretical ?g has been determined by quantum chemical calculations using DFT and semi empirical methods. HOMO, LUMO, molecular electrostatic potential (MEP) and solvent accessible surface of ORO are calculated by using DFT-B3LYP method. PMID:25123946

S?d?r, ?sa; Gülseven S?d?r, Yadigar

2015-01-25

175

Total-variation improved split Bregman method for ground penetrating radar image restoration  

NASA Astrophysics Data System (ADS)

In this paper, an improved data processing procedure is proposed for the purpose of ground penetrating radar (GPR) image restoration. The image processing method is achieved by combining the isotropic and anisotropic total-variation (TV) model of split Bregman, suppressing the staircasing effect and circumventing the edges blurred. Numerical experiments indicate that the proposed approach can well recover edges and most of the details of a (GPR) image. Hence, the proposed method is efficient in (GPR) image restoration.

Wang, Wen-peng; Zhao, Bo; Liu, Xiao-jun; Fang, Guang-you

2013-12-01

176

A method for spatial estimation of peak ground acceleration in dense arrays  

NASA Astrophysics Data System (ADS)

A methodology for the interpolation of peak ground acceleration (PGA) from discrete array stations is developed. Limited number of accelerometers or difficulty of monitoring at unreachable locations often has a negative impact on the generation of the maps of shaking after an earthquake. In locations with no recordings, PGA is inferred from interpolation of recorded PGA. The presented methodology estimates PGA at an arbitrary set of closely spaced points, in a way that is statistically compatible with known or prescribed PGA at other locations. The observed data recorded by strong motion stations of Istanbul Earthquake Rapid Response System are used for the development and validation of the new numerical method. The estimated and recorded PGAs are compared. Biased ground motion prediction equations are also considered at the comparisons. Ground motion prediction equations underestimated both observed and estimated PGAs. It has been found that the methodology is very effective for highly vulnerable mega-cities and urban areas.

Harmandar, Ebru; ?akt?, Eser; Erdik, Mustafa

2012-12-01

177

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

NASA Technical Reports Server (NTRS)

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.

Koshak, William J.

2009-01-01

178

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

NASA Astrophysics Data System (ADS)

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.

Bosch, F. P.; Gurk, M.

2009-04-01

179

A Denoising Method for Detecting Reflected Waves from Buried Objects by Ground-penetrating Radar  

NASA Astrophysics Data System (ADS)

Ground-penetrating radar is a tool for imaging the subsurfaces with radar pulses. Since a variety of media including buried objects give different dielectric constants, the positions of the buried objects can be detected on the basis of variations in the reflected return signals. This paper presents a denoising method based on the 2D-Gabor wavelet transform method to solve the pending problems in extracting the signals reflected from buried objects. The validity of our method is demonstrated by comparing it with the f-k filtering method.

Kobayashi, Makoto; Nakano, Kazushi

180

Ground-state and excitation spectra of a strongly correlated lattice by the coupled cluster method.  

PubMed

The coupled cluster method is applied to a strongly correlated lattice Hamiltonian, and the coupled cluster linear response method is extended to the calculation of electronic spectra by finding an approximation to a resolvent operator which describes the spectral response of the coupled cluster solution to excitation operators. In this spectral coupled cluster method, the ground and excited states appear as resonances in the spectra, and the resolvent can be iteratively improved in selected spectral regions. The method is applied to a MnO(2) plane model which corresponds to previous experimental works. PMID:22736514

Mirone, Alessandro

2012-09-17

181

Ground-Based Geophysical Surveys of the Northeast Greenland Ice Stream  

NASA Astrophysics Data System (ADS)

On both the Greenland and Antarctic Ice Sheets, mass discharge from the ice interior to the ocean is concentrated in large fast-flowing features, termed outlet glaciers on Greenland and ice streams in West Antarctica. In Greenland, the locations of outlet glaciers are controlled primarily by bedrock topography; in West Antarctica ice streams are dynamic and shift their location based on subglacial hydrology and subglacial sediment conditions, especially on the Siple Coast. The most dramatic exception to this general division of fast-flowing ice masses is the Northeast Greenland Ice Stream (NEGIS), an area of fast flowing ice that initiates near the ice sheet summit and drains much of the ice sheet's northeast quadrant. Although fast-flow likely initiates due to the anomalous presence of high geothermal heat flux, and thus basal melt, near the ice sheet summit, the surface expression of NEGIS is similar to that of a West Antarctic ice stream. Here we present the first ground-based geophysical data ever gathered on the NEGIS. GPS data show the ice stream is characterized by complex variations in surface topography with an amplitude of ~30 m. Ice-penetrating radar (IPR) data show the presence of internal reflecting horizons through the entire ice thickness. Although some deep layers are disturbed, indicating possible basal melt, three zones of the ice stream exhibit internal layer deformation through the entire ice column. Two of these zones correspond to the current shear margins; the third zone's origin is unclear. IPR data also show that the ice stream's location is not solely controlled by the underlying bedrock topography. Evidence for the lack of conformance of streaming flow to bedrock features, and for shifting dynamics (possible paleo-shear margins), reinforces the conclusion that this feature is similar to a West Antarctic ice stream. The presence of a West Antarctic style ice stream in Greenland highlights the ability of the ice sheet to dynamically shift basic flow behavior, possibly on relatively short, millennial or shorter, timescales. Such behavior is not included in current numerical models, but may affect future ice sheet stability.

Christianson, K.; Jacobel, R. W.; Peters, L. E.; Anandakrishnan, S.; Alley, R. B.; Riverman, K. L.; Muto, A.

2012-12-01

182

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

NASA Technical Reports Server (NTRS)

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).

Koshak, William; Solakiewicz, Richard

2013-01-01

183

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

USGS Publications Warehouse

We evaluated double-observer methods for aerial surveys as a means to adjust counts of waterfowl for incomplete detection. We conducted our study in eastern Canada and the northeast United States utilizing 3 aerial-survey crews flying 3 different types of fixed-wing aircraft. We reconciled counts of front- and rear-seat observers immediately following an observation by the rear-seat observer (i.e., on-the-fly reconciliation). We evaluated 6 a priori models containing a combination of several factors thought to influence detection probability including observer, seat position, aircraft type, and group size. We analyzed data for American black ducks (Anas rubripes) and mallards (A. platyrhynchos), which are among the most abundant duck species in this region. The best-supported model for both black ducks and mallards included observer effects. Sample sizes of black ducks were sufficient to estimate observer-specific detection rates for each crew. Estimated detection rates for black ducks were 0.62 (SE = 0.10), 0.63 (SE = 0.06), and 0.74 (SE = 0.07) for pilot-observers, 0.61 (SE = 0.08), 0.62 (SE = 0.06), and 0.81 (SE = 0.07) for other front-seat observers, and 0.43 (SE = 0.05), 0.58 (SE = 0.06), and 0.73 (SE = 0.04) for rear-seat observers. For mallards, sample sizes were adequate to generate stable maximum-likelihood estimates of observer-specific detection rates for only one aerial crew. Estimated observer-specific detection rates for that crew were 0.84 (SE = 0.04) for the pilot-observer, 0.74 (SE = 0.05) for the other front-seat observer, and 0.47 (SE = 0.03) for the rear-seat observer. Estimated observer detection rates were confounded by the position of the seat occupied by an observer, because observers did not switch seats, and by land-cover because vegetation and landform varied among crew areas. Double-observer methods with on-the-fly reconciliation, although not without challenges, offer one viable option to account for detection bias in aerial waterfowl 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.

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

2008-01-01

184

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

SciTech Connect

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.

Bao, Weizhu, E-mail: mathbaowz@nus.edu.sg [Department of Mathematics and Center for Computational Science and Engineering, National University of Singapore, Singapore 119076 (Singapore)] [Department of Mathematics and Center for Computational Science and Engineering, National University of Singapore, Singapore 119076 (Singapore); Chern, I-Liang, E-mail: chern@math.nctu.edu.tw [Department of Applied Mathematics and Center of Mathematical Modeling and Scientific Computing, National Chiao Tung University, Hsinchu 30010, Taiwan (China) [Department of Applied Mathematics and Center of Mathematical Modeling and Scientific Computing, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Department of Mathematics, National Taiwan University, Taipei 10617, Taiwan (China); Zhang, Yanzhi, E-mail: zhangyanz@mst.edu [Department of Mathematics and Statistics, Missouri University of Science and Technology, Rolla, MO 65409-0020 (United States)] [Department of Mathematics and Statistics, Missouri University of Science and Technology, Rolla, MO 65409-0020 (United States)

2013-11-15

185

Determination of ape distribution and population size using ground and aerial surveys: a case study with orang-utans in lower Kinabatangan, Sabah, Malaysia  

Microsoft Academic Search

Because of the difficulties encountered in detecting many large tropical forest-dwelling species in their natural habitat, precise figures concerning the distribution, number and trends of many populations remain deficient. In tropical forests, ground surveys are generally carried out by counting objects along straight lines. These counts require a strict compliance with the line-transect methodology before (proper design of the census),

Marc Ancrenaz; Benoit Goossens; Olivier Gimenez; Azri Sawang; Isabelle Lackman-Ancrenaz

2004-01-01

186

Symplectic partitioned Runge-Kutta methods for two-dimensional numerical model of ground penetrating radar  

NASA Astrophysics Data System (ADS)

Simulation of ground penetrating radar (GPR) wave propagation in two-dimensional (2-D) subsurface structure is developed using the symplectic partitioned Runge-Kutta (SPRK) method. A transmitting boundary is implemented to absorb waves at the edges of the modeling. For the 2-D case, the SPRK schemes require only two functions for the complete description of the electromagnetic field. To verify the performance of the proposed algorithms, results from comparisons between the SPRK schemes and the standard FDTD method are presented. In addition, a complicated subsurface structure model is considered. The wiggle trace profile of this model is obtained from forward simulation using a 2-order SPRK method.

Fang, Hongyuan; Lin, Gao

2012-12-01

187

The characteristic-resistance method for grounded semi-infinite grids  

NASA Astrophysics Data System (ADS)

It is shown that the characteristic-impedance method of analyzing lumped transmission lines can be adapted to semiinfinite half-plane resistive grids and to three-dimensional half-space resistive grids. The method yields the only current flow within the grid for which the total power dissipation is finite. It also yields a practical procedure for computing the currents and voltages in the grid. The method can also be extended to RLC grounded grids, in which each branch is a positive real impedance; this allows the computation of transient currents and voltages in the presence of energy-storage elements, but the required computer time is considerably longer.

Zemanian, A. H.

1981-01-01

188

Survey of Teaching Methods of Brookdale Community College Full-Time Teaching Faculty.  

ERIC Educational Resources Information Center

A study was conducted to investigate the teaching methods used by full-time faculty at Brookdale Community College (BCC). The study sought to collect relevant demographic data; survey the teaching methods used in an average semester and the factors influencing the selection of teaching methods; identify changes in teaching methods; and survey

Paoni, Frank John

189

A Survey on Methods for Broadband Internet Access on Trains  

Microsoft Academic Search

We present a survey of approaches for providing broadband Internet access to trains. We examine some of the barriers that hinder the use of broadband Internet on trains and then discuss some of the opportunities for broadband deployment to trains. This survey considers some of the basic concepts for providing broadband Internet access and then reviews associated network architectures. The

Daniel T. Fokum; Victor S. Frost

2010-01-01

190

Understanding Sample Surveys: Selective Learning about Social Science Research Methods  

ERIC Educational Resources Information Center

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…

Currin-Percival, Mary; Johnson, Martin

2010-01-01

191

Quantum Monte Carlo method for the ground state of many-boson systems  

SciTech Connect

We formulate a quantum Monte Carlo (QMC) method for calculating the ground state of many-boson systems. The method is based on a field-theoretical approach, and is closely related to existing fermion auxiliary-field QMC methods which are applied in several fields of physics. The ground-state projection is implemented as a branching random walk in the space of permanents consisting of identical single-particle orbitals. Any single-particle basis can be used, and the method is in principle exact. We illustrate this method with a trapped atomic boson gas, where the atoms interact via an attractive or repulsive contact two-body potential. We choose as the single-particle basis a real-space grid. We compare with exact results in small systems and arbitrarily sized systems of untrapped bosons with attractive interactions in one dimension, where analytical solutions exist. We also compare with the corresponding Gross-Pitaevskii (GP) mean-field calculations for trapped atoms, and discuss the close formal relation between our method and the GP approach. Our method provides a way to systematically improve upon GP while using the same framework, capturing interaction and correlation effects with a stochastic, coherent ensemble of noninteracting solutions. We discuss various algorithmic issues, including importance sampling and the back-propagation technique for computing observables, and illustrate them with numerical studies. We show results for systems with up to N{approx}400 bosons.

Purwanto, Wirawan; Zhang Shiwei [Department of Physics, The College of William and Mary, Williamsburg, Virginia 23187 (United States)

2004-11-01

192

A direct substitution method for multicomponent solute transport in ground water  

SciTech Connect

A numerical method was developed using a direct substitution approach for simulating one-dimensional multicomponent solute transport in ground water. The method has the ability to treat equilibrium reactions of aqueous and surface complexation, and precipitation-dissolution. The concentrations of aqueous component species, adsorbed component species, and precipitated species are chosen as the principal dependent variables. The substitution takes place after the transport equation is discretized. The resulting system of equations is solved using the Newton-Raphson method and the Jacobian matrix is computed analytically. This method is computationally more efficient than sequential iteration methods due to its faster convergence rate. It is also computationally more efficient than other direct substitution methods which compute the Jacobian matrix numerically.

Shen, H.; Nikolaidis, N.P. [Univ. of Connecticut, Storrs, CT (United States)

1997-01-01

193

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

USGS Publications Warehouse

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 method and the type of information that can be derived from its use. Documentation of the Variable-Recharge Package is provided in the appendixes and includes listings of model code and of program variables. Comment statements in the program listings provide a narrative of the code. Input-data instructions and printed model output for the package are included.

Kontis, A.L.

2001-01-01

194

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

USGS Publications Warehouse

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.

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

2007-01-01

195

Testing an automated method to estimate ground-water recharge from streamflow records  

USGS Publications Warehouse

The computer program, RORA, allows automated analysis of streamflow hydrographs to estimate ground-water recharge. Output from the program, which is based on the recession-curve-displacement method (often referred to as the Rorabaugh method, for whom the program is named), was compared to estimates of recharge obtained from a manual analysis of 156 years of streamflow record from 15 streamflow-gaging stations in the eastern United States. Statistical tests showed that there was no significant difference between paired estimates of annual recharge by the two methods. Tests of results produced by the four workers who performed the manual method showed that results can differ significantly between workers. Twenty-two percent of the variation between manual and automated estimates could be attributed to having different workers perform the manual method. The program RORA will produce estimates of recharge equivalent to estimates produced manually, greatly increase the speed od analysis, and reduce the subjectivity inherent in manual analysis.

Rutledge, A. T.; Daniel, C. C.

1994-01-01

196

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

USGS Publications Warehouse

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.

Frenzel, Steven, A.

1985-01-01

197

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

NASA Astrophysics Data System (ADS)

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 survey using a dataset compiled from previous studies of 48 observations of the topsoil thickness made through augering, profiling and drilling. We opted to measure the soil apparent electrical conductivity (ECa) using a GeonicsTM ground conductivity meter EM-31 because: i) the AB horizon thickness was within the range of penetration depth of this instrument; ii) a significant contrast between the electrical conductivities of the AB and C horizons was expected and confirmed by measurements. We assumed that the spatial variation of ECa over the study area was mainly controlled by the high clay content and the thickness of the AB horizon. The influence of the soil moisture content was minimized by taking the ECa measurements at the end of the dry season. We executed 6 transects, perpendicular to the main streams, which constituted 424 survey locations separated by a median distance of 21 m. Complementary direct observations were also made by using percussion drilling and digging at 22 locations along the geophysical transects. The second step was to convert the ECa measurements into topsoil thickness using a linear regression (LR) model. The obtained dataset was used in the third and last step to estimate the topsoil thickness over the catchment selecting the appropriate geostatistical mixed linear model (MLM). In these two last steps, the remote sensing derived auxiliary variables were tested and integrated in the models to improve the relationship. To avoid collinearity effects in the models, the auxiliary predictors were selected using principal component analysis. The selection of the appropriate geostatistical MLM was done by testing the normality and the spatial correlation of the residuals (respectively Shapiro-Wilk and Moran tests). The error propagation in the models was considered and integrated in the results. Final assessment of the estimation was made by computing the root mean square error (RMSE) at 61 locations of the observed dataset.

Francés, Alain Pascal; Lubczynski, Maciek

2010-05-01

198

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

NASA Astrophysics Data System (ADS)

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 layouts, and water-supply constraints, indicate that the number of new wells is insensitive to water-supply constraints; however, pumping rates and patterns of the existing wells are sensitive. The locations of new wells are mildly sensitive to the pond layout.

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

2008-12-01

199

Methods for Household Travel Surveys. A Synthesis of Highway Practice.  

National Technical Information Service (NTIS)

This synthesis will be of interest to planning, administrative, and traffic officials in state transportation agencies and in metropolitan planning organizations (MPOs); to consultants concerned with the design and conduct of surveys; and to those engaged...

P. R. Stopher, H. M. A. Metcalf

1996-01-01

200

Strong ground motion simulation of the 2003 Bam, Iran, earthquake using the empirical Green's function method  

NASA Astrophysics Data System (ADS)

The 2003 Bam, Iran, earthquake caused catastrophic damage to the city of Bam and neighboring villages. Given its magnitude ( M w ) of 6.5, the damage was remarkably large. Large-amplitude ground motions were recorded at the Bam accelerograph station in the center of Bam city by the Building and Housing Research Center (BHRC) of Iran. We simulated the Bam earthquake acceleration records at three BHRC strong-motion stations—Bam, Abaraq, and Mohammad-Abad—by the empirical Green's function method. Three aftershocks were used as empirical Green's functions. The frequency range of the empirical Green's function simulations was 0.5-10 Hz. The size of the strong motion generation area of the mainshock was estimated to be 11 km in length by 7 km in width. To estimate the parameters of the strong motion generation area, we used 1D and 2D velocity structures across the fault and a combined source model. The empirical Green's function method using a combination of aftershocks produced a source model that reproduced ground motions with the best fit to the observed waveforms. This may be attributed to the existence of two distinct rupture mechanisms in the strong motion generation area. We found that the rupture starting point for which the simulated waveforms best fit the observed ones was near the center of the strong motion generation area, which reproduced near-source ground motions in a broadband frequency range. The estimated strong motion generation area could explain the observed damaging ground motion at the Bam station. This suggests that estimating the source characteristics of the Bam earthquake is very important in understanding the causes of the earthquake damage.

Sadeghi, Hossein; Miyake, Hiroe; Riahi, Ali

2013-04-01

201

Results of a Flight Simulation Software Methods Survey  

NASA Technical Reports Server (NTRS)

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.

Jackson, E. Bruce

1995-01-01

202

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

USGS Publications Warehouse

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.

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

1992-01-01

203

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

PubMed Central

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

Liu, Zhao; Wang, Jinling; Liu, Daxue

2013-01-01

204

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

PubMed

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

Liu, Zhao; Wang, Jinling; Liu, Daxue

2013-01-01

205

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

NASA Astrophysics Data System (ADS)

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.

Tamjidi, Amirhossein; Ye, Cang

2012-06-01

206

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

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.

Vaccaro, J. J.

2007-01-01

207

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

NASA Astrophysics Data System (ADS)

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) Looking at their 3D patterns, most dune bedforms have a monotone profile, ruling out genesis from currents with different orientations. (4) In some outcrops however, cross-stratifications evolve laterally from stoss-erosive through aggrading to stoss-aggrading, implying that a single dune bedform can show both downstream and upstream migrating crests during the same stage of the flow. (5) Several structures cannibalized by a larger one show proof that the bed rapidly accommodates temporal changes in the dynamics of the currents.

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

2013-04-01

208

Geophysical monitoring of simulated clandestine graves using electrical and ground-penetrating radar methods: 0-3 years after burial.  

PubMed

This study provides forensic search teams with systematic geophysical monitoring data over simulated clandestine graves for comparison to active cases. Simulated "wrapped" and "naked" burials were created. Multigeophysical surveys were collected over a 3-year monitoring period. Bulk ground resistivity, electrical resistivity imaging, multifrequency ground-penetrating radar (GPR), and grave and background "soil-water" conductivity data were collected. Resistivity surveys revealed the naked burial had consistently low-resistivity anomalies, whereas the wrapped burial had small, varying high-resistivity anomalies. GPR 110- to 900-MHz frequency surveys showed the wrapped burial could be detected throughout, with the "naked" burial mostly resolved. Two hundred and twenty-five megahertz frequency GPR data were optimal. "Soil-water" analyses showed rapidly increasing (year 1), slowly increasing (year 2), and decreasing (year 3) conductivity values. Results suggest resistivity and GPR surveys should be collected if target "wrapping" is unknown, with winter to spring surveys optimal. Resistivity surveys should be collected in clay-rich soils. PMID:22509973

Pringle, Jamie K; Jervis, John R; Hansen, James D; Jones, Glenda M; Cassidy, Nigel J; Cassella, John P

2012-11-01

209

Improved method and case study of thermal response test for borehole heat exchangers of ground source heat pump system  

Microsoft Academic Search

Thermal response test (TRT) is crucial for the determination of the ground thermal conductivity and the evaluation of the thermal performance of borehole heat exchangers (BHEs) of ground source heat pump (GSHP) system. This paper presented a novel constant heating-temperature method (CHTM) for TRT. Further, a type of improved TRT equipment was developed and the mathematical model to deal with

Huajun Wang; Chengying Qi; Hongpu Du; Jihao Gu

2010-01-01

210

Draft American National Standard: Methods for measuring the vibration response of the ground.  

PubMed

Working Group 14 of the Acoustical Society of America/American National Standards Institute S2 Mechanical Vibration and Shock Committee (ASA/ANSI S2 WG14) was formed to develop a standard on methods for measuring the vibration response of the ground to be used when assessing potential impact upon vibration sensitive receivers in the vicinity of rail transit systems. The contents of the standard will be based upon industry accepted methods as described in the Federal Transit Administration guidance manual "Transit Noise and Vibration Impact Assessment" (FTA-VA-90-1003-06) while considering new developments since the latest version of the guidance manual was published in May 2006. This paper will describe the background of the methods and the structure, content, and status of the draft standard. PMID:25235562

Phillips, James E

2014-04-01

211

A comparative study of optimization methods and conventional methods for sampling design in fishery-independent surveys  

E-print Network

A comparative study of optimization methods and conventional methods for sampling design in fishery of optimization methods and conventional methods for sampling design in fishery- independent surveys. ­ ICES spatial simulated annealing method, for developing an optimal sampling design for fishery

Chen, Yong

212

A six-beam method to measure turbulence statistics using ground-based wind lidars  

NASA Astrophysics Data System (ADS)

A so-called six-beam method is proposed to measure atmospheric turbulence using a ground-based wind lidar. This method requires measurement of the radial velocity variances at five equally spaced azimuth angles on the base of a scanning cone and one measurement at the center of the scanning circle, i.e.using a vertical beam at the same height. The scanning configuration is optimized to minimize the sum of the random errors in the measurement of the second-order moments of the components (u,v, w) of the wind field. We present this method as an alternative to the so-called velocity azimuth display (VAD) method that is routinely used in commercial wind lidars, and which usually results in significant averaging effects of measured turbulence. In the VAD method, the high frequency radial velocity measurements are used instead of their variances. The measurements are performed using a pulsed lidar (WindScanner), and the derived turbulence statistics (using both methods) such as the u and v variances are compared with those obtained from a reference cup anemometer and a wind vane at 89 m height under different atmospheric stabilities. The measurements show that in comparison to the reference cup anemometer, depending on the atmospheric stability and the wind field component, the six-beam method measures between 85-101% of the reference turbulence, whereas the VAD method measures between 66-87% of the reference turbulence.

Sathe, A.; Mann, J.; Vasiljevic, N.; Lea, G.

2014-10-01

213

An Heuristic Method for GPS Surveying Stefka Fidanova  

E-print Network

, to analyze and improve the efficiency of the design of Global Positioning System (GPS) surveying networks of computational effort. The Global Positioning System is a satellite-based radio-navigation system that permits. The most widely known space systems are: the American Global Positioning System (GPS), the Russian GLObal

Fidanova, Stefka

214

Gas station flash survey - A Method for interviewing drivers  

Microsoft Academic Search

Interviews and questionnaires are very important te chniques to acquire information from the potential user. Surveys are one tool to understand users' nee ds which is in particular helpful in the early phas es of user interface design processes. To get meaningf ul information interface designers typically deter- mine the target user group for an application. Most commonly, when designing

Dagmar Kern; Albrecht Schmidt

215

FOREST SURVEY METHODS USED IN THE USDA FOREST SERVICE  

EPA Science Inventory

There has been an increasing need for forest resource inventory data to contribute to various objectives of different agencies and organizations. Monitoring forest health is one area of interest for which existing forest survey data may be useful. There are many different samplin...

216

A Survey of Eigenvector Methods for Web Information Retrieval  

Microsoft Academic Search

Web information retrieval is significantly more challenging than traditional well-controlled, small document collection information retrieval. One main difference between traditional information retrieval and Web information retrieval is the Web's hyperlink structure. This structure has been exploited by several of today's leading Web search engines, particularly Google and Teoma. In this survey paper, we focus on Web information retrieval meth- ods

Amy N. Langville; Carl D. Meyer

2003-01-01

217

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

ERIC Educational Resources Information Center

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…

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

2010-01-01

218

Helicopter-borne and ground-towed radar surveys of the Fourcade Glacier on King George Island, Antarctica  

Microsoft Academic Search

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

K. Y. Kim; J. Lee; M. H. Hong; J. K. Hong; H. Shon

2010-01-01

219

30 CFR 77.701-2 - Approved methods of grounding metallic frames, casings, and other enclosures of electric...  

...is no difference in potential between such metal enclosures and the earth. (b) A method of grounding of metallic frames, casings...potential between such frames, casings, and other enclosures, and the...

2014-07-01

220

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

USGS Publications Warehouse

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 objectives and optimize decisions related to survey bias and variance. Finally, managers and researchers involved in the survey design process must realize that obtaining the best survey results requires an interactive and recursive process of survey design, execution, analysis and redesign. Survey refinements will be possible as further knowledge is gained on the actual abundance and distribution of the population and on the most efficient techniques for detection animals.

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

1994-01-01

221

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

USGS Publications Warehouse

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.

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

222

Correction method for obtaining the variationally best ground-state pair density  

SciTech Connect

We present a correction method for the pair density (PD) to get close to the ground-state one. The PD is corrected to be a variationally best PD within the search region that is extended by adding the uniformly scaled PDs to its elements. The corrected PD is kept N-representable and satisfies the virial relation rigorously. The validity of the present method is confirmed by numerical calculations of neon atom. It is shown that the root-mean-square error of the electron-electron interaction and external potential energies, which is a good benchmark for the error of the PD, is reduced by 69.7% without additional heavy calculations.

Higuchi, Masahiko; Higuchi, Katsuhiko [Department of Physics, Faculty of Science, Shinshu University, Matsumoto 390-8621 (Japan); Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi-Hiroshima 739-8527 (Japan)

2011-10-15

223

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

USGS Publications Warehouse

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.

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

2006-01-01

224

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

USGS Publications Warehouse

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.

Hill, M. C.

1990-01-01

225

Effects of land use on ground-water quality in central Florida; preliminary results, US Geological Survey Toxic Waste-Ground Water Contamination Program  

USGS Publications Warehouse

Groundwater is the principal source of drinking water in central Florida. The most important hydrogeologic unit is the Floridan aquifer system, consisting of fractured limestone and dolomite limestone. 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 impacts of these land uses on ground-water quality by comparison with a fourth land use representing the absence of human activity in another area of recharge 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 pesticides, which include the organic compounds simazine, ametryne, chlordane, DDE , bromacil, aldicarb, EDB, trifluralin, and diazinon, and the trace elements zinc and copper; other contaminants include benzene, toluene, napthalene, 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. (Author 's abstract)

Rutledge, A. T.

1987-01-01

226

A survey of numerical methods for stochastic differential equations  

Microsoft Academic Search

The development of numerical methods for stochastic differential equations has intensified over the past decade. The earliest methods were usually heuristic adaptations of deterministic methods, but were found to have limited accuracy regardless of the order of the original scheme. A stochastic counterpart of the Taylor formula now provides a framework for the systematic investigation of numerical methods for stochastic

P. E. Kloeden; E. Platen

1989-01-01

227

A survey on evaluation methods for image segmentation  

Microsoft Academic Search

This paper studies different methods proposed so far for segmentation evaluation. Most methods can be classified into three groups: the analytical, the empirical goodness and the empirical discrepancy groups. Each group has its own characteristics. After a brief description of each method in every group, some comparative discussions about different method groups are first carried out. An experimental comparison for

Y. J. Zhang

1996-01-01

228

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

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.

Bexfield, L. M.

1998-01-01

229

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

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Ground water source microbial monitoring and analytical...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2012-07-01

230

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Ground water source microbial monitoring and analytical...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2013-07-01

231

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

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Ground water source microbial monitoring and analytical...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2011-07-01

232

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

...2014-07-01 2014-07-01 false Ground water source microbial monitoring and analytical...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule §...

2014-07-01

233

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

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…

United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Marine Sciences.

234

Thermodynamic ground state of MgB6 predicted from first principles structure search methods  

NASA Astrophysics Data System (ADS)

Crystalline structures of magnesium hexaboride, MgB6, 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 MgB6. The energy of the Cmcm structure is significantly lower than the theoretical MgB6 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 B6 octahedra and extended B? 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 MgB6 maintains a semiconducting state with permanent dipole moments. MgB6 is estimated to have much weaker electron-phonon coupling compared with that of MgB2, and therefore it is not expected to be able to sustain superconductivity at high temperatures.

Wang, Hui; LeBlanc, K. A.; Gao, Bo; Yao, Yansun

2014-01-01

235

Investigation of exciton ground state in quantum dots via Hamiltonian diagonalization method  

NASA Astrophysics Data System (ADS)

We analyze the electron-hole (exciton) ground state associated with the first peak in the optical absorption spectra of semiconductor quantum dots. We assume the effective mass approximation and a dot radius R on the order of the exciton Bohr radius aB. A Hamiltonian diagonalization method which accounts for the exciton's kinetic, direct Coulomb, and surface polarization energies is used. We obtain a representation of the exciton ground-state wavefunction and a value for its energy using a basis set consisting of only three composite infinite spherical well wavefunctions. We discuss the precision obtained by this basis set by comparing with results from a much more extended basis set. Our results are used to predict the radius-dependent energy of the first peak in visible-light absorption spectra for CdSe quantum dots. Our analysis accurately describes the experimental data for dots with radii in the range aB

Schultz, Zachary M.; Essick, John M.

2008-03-01

236

A Validation of Extraction Methods for Noninvasive Sampling of Glucocorticoids in Free-Living Ground Squirrels  

PubMed Central

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

Mateo, Jill M.; Cavigelli, Sonia A.

2008-01-01

237

Reactions to Reading ,,Remaining Consistent with Method? An Analysis of Grounded Theory Research in Accounting: A Comment on Gurd  

E-print Network

Reactions to Reading ,,Remaining Consistent with Method? An Analysis of Grounded Theory Research, published in "Qualitative Research in Accounting and Management 5, 4 (2008) 253-261" #12;methods as the rules of the method. Accordingly, the researcher is free to develop his or her own techniques

Paris-Sud XI, Université de

238

The Swift UVOT Stars Survey. I. Methods and Test Clusters  

NASA Astrophysics Data System (ADS)

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.

Siegel, Michael H.; Porterfield, Blair L.; Linevsky, Jacquelyn S.; Bond, Howard E.; Holland, Stephen T.; Hoversten, Erik A.; Berrier, Joshua L.; Breeveld, Alice A.; Brown, Peter J.; Gronwall, Caryl A.

2014-12-01

239

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

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.

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

2001-07-31

240

Gap interpolation by inpainting methods : Application to Ground and Space-based Asteroseismic data  

E-print Network

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 handle the problem, the so-called inpainting method. This technique, based on a sparsity prior, enables to judiciously fill-in the gaps in the data, preserving the asteroseismic signal, as far as possible. The impact of the observational window function is reduced and the interpretation of the power spectrum is simplified. This method is applied both on ground and space-based data. It appears that the inpainting technique improves the oscillation modes detection and estimation. Additionally, it can be used to study very long time series of many star...

Pires, Sandrine; Garcia, Rafael A; Ballot, Jérôme; Stello, Dennis; Sato, Kumiko

2014-01-01

241

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

USGS Publications Warehouse

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.

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

2000-01-01

242

The Importance of Adhering to Details of the Total Design Method (TDM) for Mail Surveys.  

ERIC Educational Resources Information Center

The empirical effects of adherence of details of the Total Design Method (TDM) approach to the design of mail surveys is discussed, based on the implementation of a common survey in 11 different states. The results suggest that greater adherence results in higher response, especially in the later stages of the TDM. (BW)

Dillman, Don A.; And Others

1984-01-01

243

Sample Weighting Methods and Estimation of Totals in the Consumer Expenditure Survey  

Microsoft Academic Search

The widely used Principal Person method of weighting households in federal government surveys uses external post-Censal information on population to improve survey sample weights by a form of poststratification. While the Principal Person Methodology can be viewed as part of a procedure to adjust for nonresponse and undercoverage, it is not oriented for efficiently incorporating ancillary information or combining information

Kimberly D. Zieschang

1990-01-01

244

A survey of tools and methods used by certified professional ergonomists  

Microsoft Academic Search

A survey of Certified Professional Ergonomists (CPEs) was conducted to gather information on the types of basic tools, direct and observational measurement techniques, and software used by practitioners. The motivation for the survey was to better understand what types of tools and methods practitioners use, their opinions of these tools, and to potentially gain an understanding of the constraints or

Patrick G. Dempsey; Raymond W. McGorry; Wayne S. Maynard

2005-01-01

245

Sampling Methods and Construction of Weights 2007 Alameda County Homeless Survey  

E-print Network

Sampling Methods and Construction of Weights for the 2007 Alameda County Homeless Survey by Thomas;1 1. OVERVIEW 1.1 Background of the Study The 2007 Alameda County Homeless Survey was designed to provide an estimate of the number of unsheltered homeless persons in Alameda County and to study

Sekhon, Jasjeet S.

246

Sampling Methods and Construction of Weights 2009 Alameda County Homeless Survey  

E-print Network

Sampling Methods and Construction of Weights for the 2009 Alameda County Homeless Survey by Thomas;1 1. OVERVIEW 1.1 Background of the Study The 2009 Alameda County Homeless Survey was designed to provide an estimate of the number of unsheltered homeless persons in Alameda County and to study

Sekhon, Jasjeet S.

247

A comparison of mail, fax and web-based survey methods  

Microsoft Academic Search

This study compares mail, fax and web-based surveys in a university setting for response speed, response rate and costs. The survey was distributed to 300 hospitality professors randomly chosen from the Council on Hotel, Restaurant, and Institutional Education members listed in the organisation's online directory as of April 2000. It was found that the fastest method was fax, with an

Cihan Cobanoglu; Bill Warde; Patrick J. Moreo

2001-01-01

248

"How many zombies do you know?" Using indirect survey methods to measure alien attacks and outbreaks  

E-print Network

"How many zombies do you know?" Using indirect survey methods to measure alien attacks and outbreaks of the undead Andrew Gelman George A. Romero 12 Mar 2010 Abstract The zombie menace has so far propose to use a new tool in survey research to allow zombies to be studied indirectly without risk

Gelman, Andrew

249

New electromagnetic surveying/ranging method for drilling parallel horizontal twin wells  

SciTech Connect

An electromagnetic source was used in conjunction with an MWD survey instrument to drill two parallel horizontal wells, with a vertical separation of 9{plus_minus}2 meters, over a length of 600 meters in Amoco`s Wolf Lake field for steam assisted gravity drainage of heavy oil. Existing wellbore survey methods are incapable of this level of precision due to cumulative survey error and associated position uncertainty. Using this new electromagnetic ranging technique, the twin wells were placed with better than 10 times the accuracy of gyro surveys.

Kuckes, A.F.; Hay, R.T.; McMahon, J. [and others

1995-12-31

250

New electromagnetic surveying/ranging method for drilling parallel horizontal twin wells  

SciTech Connect

An electromagnetic source was used in conjunction with a measurement-while-drilling (MWD) survey instrument to drill two parallel horizontal wells with a vertical separation of 9 {+-} 2 m over a length of 600 m in Amoco`s Wolf Lake field for steam-assisted gravity drainage of heavy oil. Existing wellbore survey methods are incapable of this level of precision because of cumulative survey error and associated position uncertainty. Using this new electromagnetic ranging technique, the twin wells were placed with better than 10 times the accuracy of gyro surveys.

Kuckes, A.F.; Hay, R.T.; McMahon, J.; Nord, A.G.; Schilling, D.A.; Morden, J.

1996-06-01

251

Survey of numerical methods for solution of large systems of linear equations for electromagnetic field problems  

Microsoft Academic Search

A number of the popular methods for the solution of large matrix equations are surveyed in order to find an efficient method suitable for both electromagnetic scattering and radiation problems and system identification problems. It is argued that the application of the conjugate gradient method to the analysis of large bodies by the method of moments would yield stable, reliable,

T. K. Sarkar; K. R. Siarkiewicz; R. F. Stratton

1981-01-01

252

An improved method for the electrotransformation of lactic acid bacteria: A comparative survey.  

PubMed

An efficient method for genetic transformation of lactic acid bacteria (LAB) by electroporation is presented in this work. A comparative survey with other electrotransformation methods already published showed that the method proposed here yields the higher electrotransformation efficiency in the 12 LAB strains tested, which could make the method applicable to other LAB species or genera. PMID:25086179

Landete, José M; Arqués, Juan L; Peirotén, Angela; Langa, Susana; Medina, Margarita

2014-10-01

253

Integrating case study and survey research methods: an example in information systems  

Microsoft Academic Search

The case for combining research methods generally, and more specifically that for combining qualitative and quantitative methods, is strong. Yet, research designs that extensively integrate both fieldwork (e.g. case studies) and survey research are rare. Moreover, some journals tend tacitly to specialize by methodology thereby encouraging purity of method. The multi-method model of research while not new, has not been

Guy G. Gable

1994-01-01

254

A survey of data mining methods for linkage disequilibrium mapping  

PubMed Central

Data mining methods are gaining more interest as potential tools in mapping and identification of complex disease loci. The methods are well suited to large numbers of genetic marker loci produced by high-throughput laboratory analyses, but also might be useful for clarifying the phenotype definitions prior to more traditional mapping analyses. Here, the current data mining-based methods for linkage disequilibrium mapping and phenotype analyses are reviewed. PMID:16595078

2006-01-01

255

A survey of numerical methods for transient eddy current problems  

Microsoft Academic Search

The efficiencies of different time-stepping schemes and associated algebraic system solvers for transient eddy current computations are assessed. For 2-D problems, the direct methods nested dissection (ND) and quotient minimum degree (QMD) are shown to be preferable to the incomplete Cholesky conjugate-gradient (ICCG) method, provided enough memory is available. The multilevel preconditions (MP) method is highly efficient for magnetically homogeneous

I. A. Tsukerman; A. Konrad; G. Bedrosian; M. V. K. Chari

1993-01-01

256

Mobile phones are a viable option for surveying young Australian women: a comparison of two telephone survey methods  

PubMed Central

Background Households with fixed-line telephones have decreased while mobile (cell) phone ownership has increased. We therefore sought to examine the feasibility of recruiting young women for a national health survey through random digit dialling mobile phones. Methods Two samples of women aged 18 to 39 years were surveyed by random digit dialling fixed and mobile numbers. We compared participation rates and responses to a questionnaire between women surveyed by each contact method. Results After dialling 5,390 fixed-lines and 3,697 mobile numbers, 140 and 128 women were recruited respectively. Among women contacted and found to be eligible, participation rates were 74% for fixed-lines and 88% for mobiles. Taking into account calls to numbers where eligibility was unknown (e.g. unanswered calls) the estimated response rates were 54% and 45% respectively. Of women contacted by fixed-line, 97% reported having a mobile while 61% of those contacted by mobile reported having a fixed-line at home. After adjusting for age, there were no significant differences between mobile-only and fixed-line responders with respect to education, residence, and various health behaviours; however compared to those with fixed-lines, mobile-only women were more likely to identify as Indigenous (OR 4.99, 95%CI 1.52-16.34) and less likely to live at home with their parents (OR 0.09, 95%CI 0.03-0.29). Conclusions Random digit dialling mobile phones to conduct a health survey in young Australian women is feasible, gives a comparable response rate and a more representative sample than dialling fixed-lines only. Telephone surveys of young women should include mobile dialling. PMID:22114932

2011-01-01

257

Finding a fox: an evaluation of survey methods to estimate abundance of a small desert carnivore.  

PubMed

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

Dempsey, Steven J; Gese, Eric M; Kluever, Bryan M

2014-01-01

258

Method to minimize the gravity sag of a facing ground ?1m flat mirror  

NASA Astrophysics Data System (ADS)

A method for minimizing the optical distortion from gravity sag on a suspended and autocollimated flat mirror facing ground has been proposed in the paper. Referring to this method, a mechanism consisting of 18 pulleys and weight sets unloads the gravity of the ?1m flat mirror the alignment and testing benchmark of the 1m aperture optical system of the Space Solar Telescope (SST). Three positioning points support the mirror, allow the mirror to be held or suspended above an object to be viewed steadily and reliably. 18 pulling points on the back of the mirror unload the mirror's weight. The bonded joints of these 18 points are analyzed and tested to be reliable, and can bear the affection of variation of temperature and inner stress. The manufacturing and assembling precision of the support is analyzed and controlled, the unload forces of these 18 points are assigned. With this method, the surface error of the flat tested by Ritchey-Common arrangement is satisfactory for the alignment of SST of less than 1/50? (RMS, ?=633nm).

Guo, Yongwei; Gu, Xuedong; Yang, Shimo

2006-02-01

259

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

NASA Technical Reports Server (NTRS)

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.

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

1987-01-01

260

Applicability of the Accelerated Switching Test Method - A Comprehensive Survey  

Microsoft Academic Search

The enhanced degradation exhibited at low dose rates by many bipolar-technology components is a major reliability issue for spacecraft electronics. As an accelerated ELDRS test method an approach has been suggested that makes use of sequenced high dose rate and low dose rate exposures - the so called accelerated switching test method. In this paper we describe the results of

M. Wind; P. Beck; J. Boch; L. Dusseau; M. Latocha; M. Poizat; A. Zadeh

2011-01-01

261

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

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 estimated, including volume of clay matrix, volume of matrix other than clay, density of matrix other than clay, density of matrix, intrinsic permeability, specific yield, and specific storage. Geophysical logs were used to (1) determine lithology, (2) correlate lithologic and permeable zones, (3) calibrate seismic reprocessing, (4) calibrate transient-electromagnetic surveys, and (5) calibrate uphole-survey interpretations. Logs were used at the drill site to (1) determine permeability zones, (2) determine dissolved-solids content, which is a function of water resistivity, and (3) design wells accordingly. Data and properties derived from logs were used to determine transmissivity and specific yield of aquifer materials.

Jorgensen, Donald G.; Petricola, Mario

1994-01-01

262

A Brief Survey of Multicriteria Decision Making Methods and Software Systems*  

E-print Network

3 A Brief Survey of Multicriteria Decision Making Methods and Software Systems* Vassil Vassilev and systems. Keywords: multicriteria analysis, multicriteria optimization, decision support systems production, education, ecology and other spheres can be reduced to multicriteria decision making problems

Borissova, Daniela

263

Surveys  

Cancer.gov

Behavioral Risk Factor Surveillance System (BRFSS) The world's largest, on-going telephone health survey system, tracking health conditions and risk behaviors in the United States yearly since 1984. Currently, data are collected monthly in all 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, and Guam.

264

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

NASA Astrophysics Data System (ADS)

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.

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

2012-04-01

265

survey of trust-region derivative free optimization methods  

E-print Network

results from some physical, chemical or econometrical experiment or ..... Applications of numerical optimization techniques for fluid flow problems are found .... Computer Methods in Applied Mechanics and Engineering, 190 (2001), 5297– ...

2007-06-14

266

Survey of methods for secure connection to the internet  

NASA Astrophysics Data System (ADS)

This paper describes a study of a security method of protecting inside network computers against outside miscreants and unwelcome visitors and a control method when these computers are connected with the Internet. In the present Internet, a method to encipher all data cannot be used, so that it is necessary to utilize PEM (Privacy Enhanced Mail) capable of the encipherment and conversion of secret information. For preventing miscreant access by eavesdropping password, one-time password is effective. The most cost-effective method is a firewall system. This system lies between the outside and inside network. By limiting computers that directly communicate with the Internet, control is centralized and inside network security is protected. If the security of firewall systems is strictly controlled under correct setting, security within the network can be secured even in open networks such as the Internet.

Matsui, Shouichi

1994-04-01

267

A survey of design methods for failure detection in dynamic systems  

NASA Technical Reports Server (NTRS)

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.

Willsky, A. S.

1975-01-01

268

An empirical method of RH correction for satellite estimation of ground-level PM concentrations  

NASA Astrophysics Data System (ADS)

A hygroscopic growth model suitable for local aerosol characteristics and their temporal variations is necessary for accurate satellite retrieval of ground-level particulate matters (PM). This study develops an empirical method to correct the relative humidity (RH) impact on aerosol extinction coefficient and to further derive PM concentrations from satellite observations. Not relying on detailed information of aerosol chemical and microphysical properties, this method simply uses the in-situ observations of visibility (VIS), RH and PM concentrations to characterize aerosol hygroscopicity, and thus makes the RH correction capable of supporting the satellite PM estimations with large spatial and temporal coverage. In this method, the aerosol average mass extinction efficiency (?ext) is used to describe the general hygroscopic growth behaviors of the total aerosol populations. The association between ?ext and RH is obtained through empirical model fitting, and is then applied to carry out RH correction. Nearly one year of in-situ measurements of VIS, RH and PM10 in Beijing urban area are collected for this study and RH correction is made for each of the months with sufficient data samples. The correlations between aerosol extinction coefficients and PM10 concentrations are significantly improved, with the monthly correlation R2 increasing from 0.26-0.63 to 0.49-0.82, as well as the whole dataset's R2 increasing from 0.36 to 0.68. PM10 concentrations are retrieved through RH correction and validated for each season individually. Good agreements between the retrieved and observed PM10 concentrations are found in all seasons, with R2 ranging from 0.54 in spring to 0.73 in fall, and the mean relative errors ranging from -2.5% in winter to -10.8% in spring. Based on the satellite AOD and the model simulated aerosol profiles, surface PM10 over Beijing area is retrieved through the RH correction. The satellite retrieved PM10 and those observed at ground sites agree well with each other, with R2 = 0.46 and a relative error of 19.3%.

Wang, Zifeng; Chen, Liangfu; Tao, Jinhua; Liu, Yang; Hu, Xuefei; Tao, Minghui

2014-10-01

269

Comparison of visual survey and seining methods for estimating abundance of an endangered, benthic stream fish  

USGS Publications Warehouse

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.

Jordan, F.; Jelks, H.L.; Bortone, S.A.; Dorazio, R.M.

2008-01-01

270

Determining concentrations of 2-bromoallyl alcohol and dibromopropene in ground water using quantitative methods  

USGS Publications Warehouse

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.

Panshin, Sandra Y.

1997-01-01

271

Two independent methods for mapping the grounding line of an outlet glacier - example from the Astrolabe Glacier, Terre Adélie, Antarctica  

NASA Astrophysics Data System (ADS)

The grounding line is a key element acting on the dynamics of coastal outlet glaciers. Knowing its position accurately is fundamental for both modelling the glacier dynamics and establishing a benchmark to which one can later refer in case of change. Here we map the grounding line of the Astrolabe Glacier in East Antarctica (66°41´ S; 140°05´ E), using hydrostatic and tidal methods. The first method is based on new surface and ice thickness data from which the line of buoyant flotation is found. We compare this hydrostatic map with kinematic GPS measurements of the tidal response of the ice surface. By detecting the transitions where the ice starts to move vertically in response to the tidal forcing we find control points for the grounding line position along GPS profiles. %If it can be shown that the long-term viscous mechanical behaviour of the ice slab validates the hydrostatic approach, mapping the grounding line from the ice supper surface displacements conversely requires correcting for the rigid elastic slab effect that dominates at tidal frequencies. With the help of a 2-dimensional elastic plate model, rigid elastic deviations are computed and applied to these control points. Once the extent of the grounding zone, the kinematic approach is consistent with the hydrostatic map. These two approaches lead us to propose a grounding line for the Astrolabe Glacier that significantly deviates from those obtained so far from satellite imagery.

Le Meur, E.; Sacchettini, M.; Garambois, S.; Berthier, E.; Drouet, A. S.; Durand, G.; Young, D.; Greenbaum, J. S.; Blankenship, D. D.; Holt, J. W.; Rignot, E.; Mouginot, J.; Gim, Y.; Kirchner, D.; de Fleurian, B.; Gagliardini, O.; Gillet-Chaulet, F.

2013-08-01

272

Assessing the oral health of an ageing population: methods, challenges and predictors of survey participation  

PubMed Central

Assessing the oral health of an ageing population: methods, challenges and predictors of survey participation Objectives To examine predictors of participation and to describe the methodological considerations of conducting a two-stage population-based oral health survey. Methods An observational, cross-sectional survey (telephone interview and clinical oral examination) of community-dwelling adults aged 45–64 and ?65 living in Nova Scotia, Canada was conducted. Results The survey response rate was 21% for the interview and 13.5% for the examination. A total of 1141 participants completed one or both components of the survey. Both age groups had higher levels of education than the target population; the age 45–64 sample also had a higher proportion of females and lower levels of employment than the target population. Completers (participants who completed interview and examination) were compared with partial completers (who completed only the interview), and stepwise logistic regression was performed to examine predictors of completion. Identified predictors were as follows: not working, post-secondary education and frequent dental visits. Conclusion Recruitment, communications and logistics present challenges in conducting a province-wide survey. Identification of employment, education and dental visit frequency as predictors of survey participation provide insight into possible non-response bias and suggest potential for underestimation of oral disease prevalence in this and similar surveys. This potential must be considered in analysis and in future recruitment strategies. PMID:21916953

Matthews, Debora C; Brillant, Martha G S; Clovis, Joanne B; McNally, Mary E; Filiaggi, Mark J; Kotzer, Robert D; Lawrence, Herenia P

2012-01-01

273

"Estimation of Ground and Excited State Dipole Moments of aryl Boronic acid Derivative by Solvatochromic Shift Method".  

PubMed

In the present work, the absorption and fluorescence spectra of newly synthesized aryl boronic acid derivative namely 2-Methylphenyl boronic acid (2MPBA) have been recorded in various solvents of different polarities. The ground state dipole moment of 2MPBA was obtained from quantum chemical calculations. Solvatochromic correlations were used to estimate the ground state (? g ) and excited state (? e ) dipole moments. The excited state dipole moments are observed to be greater than the ground state dipole moment and ground and excited state dipole moments are not parallel but subtend by an angle of 88(0). Further, the changes in dipole moment (??) were calculated both from solvatochromic shift method and microscopic solvent polarity parameter (E T (N) ), and the value are compared. The spectral variations were analyzed by Kamlet-Taft parameters. PMID:25231695

Muddapur, G V; Patil, N R; Patil, S S; Melavanki, R M; Kusanur, R A

2014-11-01

274

A (Revised) Survey of Approximate Methods for Solving Partially Observable Markov Decision Processes  

Microsoft Academic Search

Partially observable Markov decision processes (POMDPs) are inter- esting because they provide a general framework for learning in the pres- ence of multiple forms of uncertainty. We survey methods for learning within the POMDP framework. Because exact methods are intractable we concentrate on approximate methods. We explore two versions of the POMDP training problem: learning when a model of the

Douglas Aberdeen

275

A survey of the effects of a fourth year Introduction to Research Methods course  

E-print Network

A survey of the effects of a fourth year Introduction to Research Methods course Vashti Galpin an introductory research methods Honours course to increase our students' exposure to research and to help them with the Honours research reports prior to the introduction of the research methods course have been alleviated. 1

Galpin, Vashti

276

A Comparison between Survey and Verbal Choice Methods of Identifying Potential Reinforcers among Employees  

ERIC Educational Resources Information Center

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…

Wilder, David A; Therrien, Kelly; Wine, Byron

2006-01-01

277

Inverse Combinatorial Optimization: A Survey on Problems, Methods, and Results  

Microsoft Academic Search

Given a (combinatorial) optimization problem and a feasible solution to it, the correspond- ing inverse optimization problem is to nd a minimal adjustment of the cost function such that the given solution becomes optimum. Several such problems have been studied in the last ten years. After formalizing the notion of an inverse problem and its variants, we present various methods

Clemens Heuberger

2004-01-01

278

A Survey of Current Methods in Medical Image Segmentation  

Microsoft Academic Search

Image segmentation plays a crucial role in many medical imaging applications by automat- ing or facilitating the delineation of anatomical structures and other regions of interest. We present herein a critical appraisal of the current status of semi-automated and automated methods for the segmentation of anatomical medical images. Current segmentation approaches are reviewed with an emphasis placed on revealing the

Dzung L. Pham; Jerry L. Prince

1999-01-01

279

NCES Handbook of Survey Methods. NCES 2011-609  

ERIC Educational Resources Information Center

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,…

Burns, Shelley, Ed.; Wang, Xiaolei, Ed.; Henning, Alexandra, Ed.

2011-01-01

280

A hybrid method of simulating broadband ground motion : A case study of the 2006 Pingtung earthquake, Taiwan  

NASA Astrophysics Data System (ADS)

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

Yen, Y.; Ma, K.; Cheng, C.; Shao, K.; Lin, P.

2011-12-01

281

A survey of numerical methods for shock physics applications  

SciTech Connect

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.

Hertel, E.S. Jr.

1997-10-01

282

A Comparison of Web-Based and Paper-Based Survey Methods: Testing Assumptions of Survey Mode and Response Cost  

ERIC Educational Resources Information Center

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…

Greenlaw, Corey; Brown-Welty, Sharon

2009-01-01

283

Parallel octree-based multiresolution mesh method for large-scale earthquake ground motion simulation  

NASA Astrophysics Data System (ADS)

Large scale ground motion simulation requires supercomputing systems in order to obtain reliable and useful results within reasonable elapsed time. In this study, we develop a framework for terascale ground motion simulations in highly heterogeneous basins. As part of the development, we present a parallel octree-based multiresolution finite element methodology for the elastodynamic wave propagation problem. The octree-based multiresolution finite element method reduces memory use significantly and improves overall computational performance. The framework is comprised of three parts; (1) an octree-based mesh generator, Euclid developed by TV and O'Hallaron, (2) a parallel mesh partitioner, ParMETIS developed by Karypis et al.[2], and (3) a parallel octree-based multiresolution finite element solver, QUAKE developed in this study. Realistic earthquakes parameters, soil material properties, and sedimentary basins dimensions will produce extremely large meshes. The out-of-core versional octree-based mesh generator, Euclid overcomes the resulting severe memory limitations. By using a parallel, distributed-memory graph partitioning algorithm, ParMETIS partitions large meshes, overcoming the memory and cost problem. Despite capability of the Octree-Based Multiresolution Mesh Method ( OBM3), large problem sizes necessitate parallelism to handle large memory and work requirements. The parallel OBM 3 elastic wave propagation code, QUAKE has been developed to address these issues. The numerical methodology and the framework have been used to simulate the seismic response of both idealized systems and of the Greater Los Angeles basin to simple pulses and to a mainshock of the 1994 Northridge Earthquake, for frequencies of up to 1 Hz and domain size of 80 km x 80 km x 30 km. In the idealized models, QUAKE shows good agreement with the analytical Green's function solutions. In the realistic models for the Northridge earthquake mainshock, QUAKE qualitatively agrees, with at most a factor of 2.5, with the observational data. Through simulations for several models, ranging in size from 400,000 to 300 million degrees of freedom on the 512-processors Cray T3E and the 3000-processors HP-Compaq AlphaServer Cluster at the Pittsburgh Supercomputing Center, we achieve excellent performance and scalability.

Kim, Eui Joong

284

A new control method for 400Hz ground power units for airplanes  

Microsoft Academic Search

This paper presents a new control strategy for a ground power unit, which is used for airplanes on the ground. In such a system, the ratio between the switching frequency and the fundamental frequency is low and in order to obtain high output performance, the controller has to be digital. The control is performed by a pulsewidth modulator and a

Uffe Borup Jensen; Frede Blaabjerg; John K. Pedersen

2000-01-01

285

Exact ground state Monte Carlo method for Bosons without importance sampling  

Microsoft Academic Search

Generally ``exact'' quantum Monte Carlo computations for the ground state of many bosons make use of importance sampling. The importance sampling is based either on a guiding function or on an initial variational wave function. Here we investigate the need of importance sampling in the case of path integral ground state (PIGS) Monte Carlo. PIGS is based on a discrete

M. Rossi; M. Nava; L. Reatto; D. E. Galli

2009-01-01

286

Influence of Uncertain Source Parameters on Strong Ground Motion Simulation with the Empirical Green's Function Method  

Microsoft Academic Search

A combined stochastic and Green's function approach was developed to simulate strong ground motions in Southwest Western Australia (SWWA) in a previous study. Although it was demonstrated that adopting the source parameters derived from other regions yielded reasonable simulation of ground motions in SWWA as compared with a few available strong motion records, the effect of source parameter variations on

Jonathan Z. Liang; Hong Hao

2009-01-01

287

A Survey of Synchronization Methods for Parallel Computers  

Microsoft Academic Search

An examination is given of how traditional synchronization methods influence the design of MIMD (multiple-instruction multiple-data-stream) multiprocessors. She provides an overview of MIMD multiprocessing and goes on to discuss semaphore-based implementations (Ultracomputers, Cedar, and the Sequent Balance\\/21000), monitor-based implementations (the HM\\/sup 2\\/p) and implementations based on message-passing (HEP, the BBN Butterfly and the Transputer).

Anne Dinning

1989-01-01

288

Gamma/hadron segregation for a ground based imaging atmospheric Cherenkov telescope using machine learning methods: Random Forest leads  

NASA Astrophysics Data System (ADS)

A detailed case study of ?-hadron segregation for a ground based atmospheric Cherenkov telescope is presented. We have evaluated and compared various supervised machine learning methods such as the Random Forest method, Artificial Neural Network, Linear Discriminant method, Naive Bayes Classifiers, Support Vector Machines as well as the conventional dynamic supercut method by simulating triggering events with the Monte Carlo method and applied the results to a Cherenkov telescope. It is demonstrated that the Random Forest method is the most sensitive machine learning method for ?-hadron segregation.

Sharma, Mradul; Nayak, Jitadeepa; Krishna Koul, Maharaj; Bose, Smarajit; Mitra, Abhas

2014-11-01

289

Gamma/hadron segregation for a ground based imaging atmospheric Cherenkov telescope using machine learning methods: Random Forest leads  

E-print Network

A detailed case study of $\\gamma$-hadron segregation for a ground based atmospheric Cherenkov telescope is presented. We have evaluated and compared various supervised machine learning methods such as the Random Forest method, Artificial Neural Network, Linear Discriminant method, Naive Bayes Classifiers,Support Vector Machines as well as the conventional dynamic supercut method by simulating triggering events with the Monte Carlo method and applied the results to a Cherenkov telescope. It is demonstrated that the Random Forest method is the most sensitive machine learning method for $\\gamma$-hadron segregation.

Sharma, Mradul; Koul, M K; Bose, S; Mitra, Abhas

2014-01-01

290

Measuring galaxy [O ii] emission line doublet with future ground-based wide-field spectroscopic surveys  

NASA Astrophysics Data System (ADS)

The next generation of wide-field spectroscopic redshift surveys will map the large-scale galaxy distribution in the redshift range 0.7 ? z ? 2 to measure baryonic acoustic oscillations (BAO). The primary optical signature used in this redshift range comes from the [Oii] emission line doublet, which provides a unique redshift identification that can minimize confusion with other single emission lines. To derive the required spectrograph resolution for these redshift surveys, we simulate observations of the [Oii] (?? 3727, 3729) doublet for various instrument resolutions, and line velocities. We foresee two strategies for the choice of the resolution for future spectrographs for BAO surveys. For bright [Oii] emitter surveys ([Oii] flux ~30 × 10-17 erg cm-2 s-1 like SDSS-IV/eBOSS), a resolution of R ~ 3300 allows the separation of 90 percent of the doublets. The impact of the sky lines on the completeness in redshift is less than 6 percent. For faint [Oii] emitter surveys ([Oii] flux ~10 × 10-17 erg cm-2 s-1 like DESi), the detection improves continuously with resolution, so we recommend the highest possible resolution, the limit being given by the number of pixels (4k by 4k) on the detector and the number of spectroscopic channels (2 or 3).

Comparat, Johan; Kneib, Jean-Paul; Bacon, Roland; Mostek, Nick J.; Newman, Jeffrey A.; Schlegel, David J.; Yèche, Christophe

2013-11-01

291

Ground Penetrating Radar, a Method for Exploration and Monitoring of Coal Fires in China  

NASA Astrophysics Data System (ADS)

Due to the climate change it is a global task to fight against gas emission of coal fires. In China exists many burning coal seams which should be extinguished. A Chinese-German initiative tries to find new technologies and solutions to control these fires. Most of the fires are close to the surface in arid areas. In that case GPR is a possible geophysical method to get detailed information about the structure of the soil. Mining activities and the burning coal are leaving voids which collapse or still exist as dangerous areas. With GPR it is possible to detect voids and clefts. Crevices are potential paths for oxygen transport from the surface to the fire. The knowledge of these structures would help to extinguish the fire. The heat of the burning coal changes the permittivity and the conductivity of the rock. This affects the radar signal and makes it possible to separate burning zones from intact zones. Monitoring of the burning zones helps to find optimal solutions for fire extinguishing strategies. Several field campaigns were made in China. One campaign was in the province Xinjiang with a 50 MHz system from Mala on a steep dipping coal seam. Other campaigns were in the Inner Mongolia with 40 MHz to 200 MHz antennae from GSSI on shallow dipping coal seams. The experiences from these measurements will be shown. The surveys were collected in rough terrain. The data from the unshielded antennae contained a lot of effects coming through the air. The limits of detecting crevices with GPR will be demonstrated. Some parts of the measurements over burning coal were influenced by strong anomalies of the magnetization. Modeling of the radar signal helps at the interpretation. Parts of the interpretation from the surveys can be validated by the outcrop of the investigated structures. A spatial visualization of the results is the basis for discussions.

Gundelach, Volker

2010-05-01

292

Research of Stability Problems on Ankara-Konya High Speed Railway Line (Turkey) using Ground Penetrating Radar and Petrographical Methods  

NASA Astrophysics Data System (ADS)

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. The petrographical studies and GPR results indicated that the areas with Jurassic alloctonous limestones thrusted on the ophiolitic rocks had deep and large fractures and cavities. The resulted radargrams indicated the thrust fault locations under the rail line. This limestone did not have a root and did not have big thickness. Therefore, the limestone could be move on the ophiolitic serpentinite unit. There were approximately horizontal and thin fracture segments under some parts of the tunnel nearly 8m in depth. There was an important collapsed zone filled up before. At the same time, there were thin and short fractures in the Jurassic limestone under the tunnel which was seen clearly on the radargrams. However, it was appeared that the hazard could not me removed completely because of the horizontal fracture. The areas with lacustrine limestones included disordered small fractures. Finally some areas had terra rossa because of the results of a large karstification. These areas could cause soil liquefaction during rainy season. The stability of these areas has to be controlled with ordered small periods.

Kadioglu, S.; Kadioglu, Y. K.

2012-04-01

293

Innovative RDWT: a new DWT-based method with applications for seismic ground roll attenuation  

NASA Astrophysics Data System (ADS)

The presence of noise in seismic data is inevitable. In land seismic data acquisition, ground roll noise masks reflection events so that observation of reflection events is not usually easy to interpret. It is the exploration seismologist's task to attenuate ground roll to improve the data quality and to enhance the signal-to-noise ratio. Investigations have suggested that the wavelet transform is an efficient tool for such a purpose. In this study, a new type of discrete wavelet transform, known as the rational-dilation wavelet transform (RDWT), is used to attenuate ground roll. Compared with the common DWTs, the RDWT offers a wide range of redundancies and Q-factors (wavelet centre frequency/bandwidth), to help the user choose an appropriate Q-factor, and hence provides more satisfactory results in ground roll attenuation while better preserving the signal. In this transform, the Q-factor is determined by selecting a number of parameters. True parameter selection results in better performance of ground roll attenuation. Depending on the nature of the ground roll, the parameters may vary in each shot-gather. Due to the over-completeness of the transformation, aliasing is less problematic compared to other DWTs. This paper discusses and indicates the advantages and capability of RDWT, by applying it to synthetic and real shot-gathered data with the purpose of ground roll attenuation, and compares the results with the application of f-k and band-pass filters.

Irani Mehr, Mohammad; Riahi, Mohammad Ali; Goudarzi, Alireza

2013-08-01

294

Gaussian-Basis Monte Carlo Method for Numerical Study on Ground States of Itinerant and Strongly Correlated Electron Systems  

Microsoft Academic Search

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 \\\\hatrho by means of the coherent Gaussian-type operator basis \\\\hatLambda 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

Takeshi Aimi; Masatoshi Imada

2007-01-01

295

Proceedings of the sudden oak death second science symposium: the state of our knowledge A Case Study to Evaluate Ground-Based,  

E-print Network

Study to Evaluate Ground-Based, Wildland Survey Methods for Phytophthora ramorum in Coast Live Oak: Phytophthora ramorum, survey methods 1 An abstract of a poster presented at the Sudden Oak Death Second Science

Standiford, Richard B.

296

Shifting ground: archaeological surveys of upland Adak Island, the Aleutian Islands, Alaska and changing assumptions of Unangan land use patterns  

Microsoft Academic Search

Archaeological site surveys in the Aleutian archipelago of western Alaska understandably focused along the shoreline, based on an assumption that land resources were a minor contribution to Unangan life. This view was the dominant but not unanimous view from the 1960s through the 1990s. There were occasional reports of upland sites. In 2007 through 2009, a concerted effort was made

Diane K. Hanson; Debra G. Corbett

2010-01-01

297

Long-Term Behavior of a Slow-Moving Landslide Inferred From Ground-Based Surveys and Analysis of Digital Terrain Models  

NASA Astrophysics Data System (ADS)

Movement of Minor Creek landslide in Humboldt County, northwestern California, has been monitored for almost thirty years. We report movement patterns and sediment yields derived from repetitive ground-based surveys and supplement them with inferences from analysis of digital terrain models (DTMs) created from aerial photographs taken in 1982 and 2001. The landslide consists predominantly of gravelly, sandy clay, has earthflow-like morphology, an average surface slope of 15 degrees, is 800 m long, averages 100 m wide, and is vegetated primarily by grasses and scattered trees. Its thickness, inferred from inclinometer data, ranges from 3 to more than 8 m. The landslide moves each winter rainy season in response to rising pore-water pressures, and movement ceases during the dry summer months (see Iverson and Major, GSA Bulletin, 99, 579-594, 1987). Annual downslope surface displacements measured by ground surveys average 0.42 m. Deviations from average surface displacement occur in both time and space: three large pulses of displacement (during winters of 1973-74, 1983-84, and 1997-98), averaging 1.7 m each, account for 64% of the total displacement between 1973 and 2000. Movement pulses are pronounced in the middle and lower portion of the landslide, whereas near the head of the landslide, pulses are less pronounced, and the pace of movement more uniform. Surface displacements at the toe of the landslide, which is relatively thin and abuts Minor Creek, average 280% of those elsewhere. On the basis of measured surface displacements and subsurface deformation, we estimate a net flux of 4000 m3 of landslide sediment into Minor Creek between 1973 and 2000. While ground-based surveying provides excellent resolution of landslide movement at a finite number of pre-determined survey locations, differencing of high-resolution (0.65-m cell size) DTMs constructed from 1982 and 2001 aerial photographs provides a quantitative picture of the spatial distribution of vertical displacements and the complex pattern of landslide movement. Much of the headscarp and toe areas of the landslide exhibited significant surface lowering between 1982 and 2001, and an area about 150 m downslope from the headscarp showed a significant increase in elevation over this same time period. Although the DTMs provide a good spatial picture of changes in landslide topography, their vertical accuracy is not sufficient to reliably quantify the relatively small changes in landslide sediment volume, which represent a 5 cm elevation decrease averaged over the landslide surface area. Thus the DTMs do not provide good resolution of the landslide sediment flux to Minor Creek over this 19-year period.

Mark, L. E.; Iverson, R. M.; Messerich, J. A.

2002-12-01

298

Methods and Strategies: The Common Ground -- A rationale for integrating science and reading  

NSDL National Science Digital Library

Building on the common ground between subjects through integration helps teachers address learning goals in both subjects without compromising either. This article addresses ways to integrate science with language arts objectives.

Royce, Christine A.; Wiley, David A.

2005-02-01

299

Indigo snake capture methods: effectiveness of two survey techniques for Drymarchon couperi in Georgia  

USGS Publications Warehouse

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.

Hyslop, N.L.; Meyers, J.M.; Cooper, R.J.; Stevenson, J.

2009-01-01

300

Functional restrictions on the orientation of onboard and ground methods in the RadioAstron project  

NASA Astrophysics Data System (ADS)

In this paper, functional restrictions on the orientation of the onboard systems of the space radio telescope, stations of scientific data receiving and ground radio telescopes in the RadioAstron project are considered. Restrictions important for practical problems of scheduling observations with ground-space radio interferometer are discussed in detail. An algorithm for calculating the angles of the narrow-beam antenna drive, which takes into account technological restrictions on the capability of its spatial orientation, is presented.

Voinakov, S. M.; Filippova, E. N.; Sheikhet, A. I.; Yakimov, V. E.

2014-09-01

301

How should social mixing be measured: comparing web-based survey and sensor-based methods  

PubMed Central

Background Contact surveys and diaries have conventionally been used to measure contact networks in different settings for elucidating infectious disease transmission dynamics of respiratory infections. More recently, technological advances have permitted the use of wireless sensor devices, which can be worn by individuals interacting in a particular social context to record high resolution mixing patterns. To date, a direct comparison of these two different methods for collecting contact data has not been performed. Methods We studied the contact network at a United States high school in the spring of 2012. All school members (i.e., students, teachers, and other staff) were invited to wear wireless sensor devices for a single school day, and asked to remember and report the name and duration of all of their close proximity conversational contacts for that day in an online contact survey. We compared the two methods in terms of the resulting network densities, nodal degrees, and degree distributions. We also assessed the correspondence between the methods at the dyadic and individual levels. Results We found limited congruence in recorded contact data between the online contact survey and wireless sensors. In particular, there was only negligible correlation between the two methods for nodal degree, and the degree distribution differed substantially between both methods. We found that survey underreporting was a significant source of the difference between the two methods, and that this difference could be improved by excluding individuals who reported only a few contact partners. Additionally, survey reporting was more accurate for contacts of longer duration, and very inaccurate for contacts of shorter duration. Finally, female participants tended to report more accurately than male participants. Conclusions Online contact surveys and wireless sensor devices collected incongruent network data from an identical setting. This finding suggests that these two methods cannot be used interchangeably for informing models of infectious disease dynamics. PMID:24612900

2014-01-01

302

Survey of methods of teaching and learning in undergraduate pharmacology within UK higher education  

Microsoft Academic Search

Many of the pharmacology teachers surveyed in a questionnaire on pharmacology teaching and learning are aware of nontraditional teaching and learning methods and believe they are both appropriate to the discipline and effective in producing learning gain in the students. The reasons that nontraditional teaching methods are not used extensively include a shortage of staff time together with a perception

T. Markham; S. J. Jone; I. Hughes; M. Sutcliffe

1998-01-01

303

A Survey of Methods of Deriving Individual Grades from Group Assessments  

Microsoft Academic Search

This paper surveys the different methods of assessing groups of students which have been reported in the literature and describes some novel methods which have been used at the University of Sunderland. It relates the work of Schechtman to peer assessment in a group setting, discusses some observations on self?assessment and raises some questions for debate and future research.

Mark Lejk; Michael Wyvill; Stephen Farrow

1996-01-01

304

A survey method for estimating potential levels of mangrove forest primary production  

Microsoft Academic Search

Measurements of net photosynthesis in mangrove communities by direct methods is technically and logistically difficult. Recording litter fall alone neglects other important components of production. A method has been developed which lends itself to ready application for obtaining survey estimates of photosynthetic yield. The procedure involves measurement of light attenuation through forest canopies attributable to photosynthetic utilization and standardized against

J. S. Bunt; K. G. Boto; G. Boto

1979-01-01

305

"Same, Same but Different" A Survey on Duplicate Detection Methods for  

E-print Network

"Same, Same but Different" A Survey on Duplicate Detection Methods for Situation Awareness Norbert Abstract. Systems supporting situation awareness typically deal with a vast stream of information about examines existing duplicate detection methods ap- pearing to be suitable in the area of situation awareness

Hochreiter, Sepp

306

Evaluation of Two Survey Methods for Detection of Helminth Infections in \\\\White? tailed Deer (Odocoileus virginianus)  

Microsoft Academic Search

White-tailed deer, Odocoileus virginianus, from central Pennsyl- vania were examined for helminth parasites by regular autopsy pro- cedures supplemented by a direct centrifugal flotation technique. The two methods were compared and evaluated for suitability in diagnosis and survey work. The reliability and repeatability of the flotation method were studied. Prevalence of most nematodes encountered was increased as a direct result

W. M. SAMUEL; R. L. BEAUDOIN

1966-01-01

307

Using on-line and CD-ROM database archives as an adjunct to teaching survey research methods  

Microsoft Academic Search

Many undergraduate courses in research methods include a section on surveys. A number of practical issues can interfere with\\u000a the design and implementation of student survey research and often preclude the completion of well-designed survey studies.\\u000a This paper examines the use of on-line and CD-ROM databases as an alternative to student-designed survey instruments. Problems\\u000a faced by student survey researchers can

Douglas B. Eamon

2001-01-01

308

When have we looked hard enough? A novel method for setting minimum survey effort protocols for flora surveys  

E-print Network

for flora surveys GEORGIA E. GARRARD,1 * SARAH A. BEKESSY,1 MICHAEL A. McCARTHY2 AND BRENDAN A. WINTLE2 1 the detectability of plants and animals under standard survey conditions. Despite the evidence that many flora appropriate survey effort for plant species during flora surveys.We provide computer code for implementing

Burgman, Mark

309

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...

310

Air Pollution Control Measurement of Ground Level Ozone with the Photometric Method Uncertainty Analysis of the Sampling Phase  

Microsoft Academic Search

The main purpose of this paper is to present the environmental monitoring of air pollution by ground level ozone with the photometric UV method. The uncertainty and the weights of the main variables influencing the sampling phase of the measurements are studied.

G. Andria; M. P. Sassi; A. Campo; A. L. Ribeiro; A. M. L. Lanzolla

2007-01-01

311

Using grounded theory method for theory building in operations management research : A study on inter-firm relationship governance  

Microsoft Academic Search

Purpose – Qualitative theory building approaches, such as grounded theory method (GTM), are still not very widespread and rigorously applied in operations management (OM) research. Yet it is agreed that more systematic observation of current industrial phenomena is necessary to help managers deal with their problems. The purpose of this paper is to provide an example to help guide other

Mario Binder; John S. Edwards

2010-01-01

312

Quality assessment of restored soils: combination of classical soil science methods with ground penetrating radar and near infrared aerial photography?  

Microsoft Academic Search

In Switzerland agricultural land is usually restored after gravel exploitation. In order to minimize soil damage, the quality of restored soils should be checked by the authorities. To assess the physical soil properties, a combination of classical soil science methods with ground-penetrating radar (GPR) and near infrared (IR) aerial photography was tested in 1994–1995. GPR profiles were recorded in the

B. Friedli; S. Tobias; M. Fritsch

1998-01-01

313

Method and basis set dependence of anharmonic ground state nuclear wave functions and zero-point energies: Application to SSSH  

Microsoft Academic Search

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

Stephen J. Kolmann; Meredith J. T. Jordan

2010-01-01

314

Computer Program for Thin Wire Antenna over a Perfectly Conducting Ground Plane. [using Galerkins method and sinusoidal bases  

NASA Technical Reports Server (NTRS)

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.

Richmond, J. H.

1974-01-01

315

A HELICOPTER-BASED SURVEY METHOD FOR MONITORING THE NESTING COMPONENT OF SNOW GOOSE COLONIES  

Microsoft Academic Search

A new strip transect method to monitor numbers of nesting snow geese (Chen caerulescens) employs a helicopter to fly three observers at a low level (100 feet above ground level (AGL)) along fixed transects over the colony. Observers count all snow goose nests within the transect belt which is 100 m wide. The aircraft's Global Positioning System (GPS) is used

R. KENYON ROSS; KENNETH F. ABRAHAM; DONALD FILLMAN; BRIAN T. COLLINS; RICHARD H. KERBES

316

Suitability of the Respirometric Bod Oxitop Method for Determining the Biodegradability of Oils in Ground Water using Forestry Hydraulic Oils as Model Compounds  

Microsoft Academic Search

Different forestry hydraulic oils were used as model compounds for evaluating the applicability of the respirometric BOD Oxitop method in following the progress of biodegradation of oils in ground water. It is obvious that the biodegradability values of substances depend on the measurement medium used. In this study the same ground water was used in all the ground water experiments.

Toivo Kuokkanen; Pekka Vähäoja; Ilkka Välimäki; Risto Lauhanen

2004-01-01

317

Development of optical ground verification method for ?m to sub-mm reflectors  

NASA Astrophysics Data System (ADS)

Large reflectors and antennas for the IR to mm wavelength range are being planned for many Earth observation and astronomical space missions and for commercial communication satellites as well. Scientific observatories require large telescopes with precisely shaped reflectors for collecting the electro-magnetic radiation from faint sources. The challenging tasks of on-ground testing are to achieve the required accuracy in the measurement of the reflector shapes and antenna structures and to verify their performance under simulated space conditions (vacuum, low temperatures). Due to the specific surface characteristics of reflectors operating in these spectral regions, standard optical metrology methods employed in the visible spectrum do not provide useful measurement results. The current state-of-the-art commercial metrology systems are not able to measure these types of reflectors because they have to face the measurement of shape and waviness over relatively large areas with a large deformation dynamic range and encompassing a wide range of spatial frequencies. 3-D metrology (tactile coordinate measurement) machines are generally used during the manufacturing process. Unfortunately, these instruments cannot be used in the operational environmental conditions of the reflector. The application of standard visible wavelength interferometric methods is very limited or impossible due to the large relative surface roughnesses involved. A small number of infrared interferometers have been commercially developed over the last 10 years but their applications have also been limited due to poor dynamic range and the restricted spatial resolution of their detectors. These restrictions affect also the surface error slopes that can be captured and makes their application to surfaces manufactured using CRFP honeycomb technologies rather difficult or impossible. It has therefore been considered essential, from the viewpoint of supporting future ESA exploration missions, to develop and realise suitable verification tools based on infrared interferometry and other optical techniques for testing large reflector structures, telescope configurations and their performances under simulated space conditions. The first one is an IR-phase shifting interferometer with high spatial resolution. This interferometer shall be used specifically for the verification of high precision IR, FIR and sub-mm reflector surfaces and telescopes under both ambient and thermal vacuum conditions. The second one presented hereafter is a holographic method for relative shape measurement. The holographic solution proposed makes use of a home built vacuum compatible holographic camera that allows displacement measurements from typically 20 nanometres to 25 microns in one shot. An iterative process allows the measurement of a total of up to several mm of deformation. Uniquely the system is designed to measure both specular and diffuse surfaces.

Stockman, Y.; Thizy, C.; Lemaire, P.; Georges, M.; Mazy, E.; Mazzoli, A.; Houbrechts, Y.; Rochus, P.; Roose, S.; Doyle, D.; Ulbrich, G.

2004-06-01

318

Method for validating cloud mask obtained from satellite measurements using ground-based sky camera.  

PubMed

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

Letu, Husi; Nagao, Takashi M; Nakajima, Takashi Y; Matsumae, Yoshiaki

2014-11-01

319

New inverse method for simultaneous reconstruction of object buried beneath rough ground and the ground surface structure using SAMM forward model  

NASA Astrophysics Data System (ADS)

A new inverse scattering method is presented to reconstruct the rough interface separating the air and ground as well as the structure of the object buried beneath this interface. Simultaneous reconstruction of the interface and object is posed as a nonlinear least-squares optimization problem for a parametric representation of the boundaries with a cost function defined by the misfit of modelled to true data. We make use of a newly-developed forward model, the Semi-Analytic Mode Matching method (SAMM), within the context of the inversion procedure where a moderately low-order superposition of cylindrical modes (in 2-D configuration) satisfying the Helmholtz wave equation are used to represent the scattered fields from the interface and object. The proposed inverse method is a combined analytical-numerical algorithm to decrease the cost function by optimizing the boundary control parameters in an iterative procedure. The shape of the object as well as the interface is defined in low-dimensional parametric form modelled by B-spline curves which are parameterized by the collection of "control points". Accuracy and reliability of this method is verified by numerical experiments.

Firoozabadi, Reza; Miller, Eric L.; Rappaport, Carey M.; Morgenthaler, Ann W.

2005-03-01

320

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

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.

Mehl, Steffen W.; Hill, Mary C.

2006-01-01

321

Numerical Green's function method: Application to quantifying ground motion variations of M7 earthquakes  

NASA Astrophysics Data System (ADS)

The concept of “numerical Green’s functions” (NGF or Green’s function database) is developed. The basic idea is: a large seismic fault is divided into subfaults of appropriate size, for which synthetic Green’s functions at the surface (NGF) are calculated and stored. Consequently, ground motions from arbitrary kinematic sources can be simulated, rapidly, for the whole fault or parts of it by superposition. The target fault is a simplified, vertical model of the Newport-Inglewood fault in the Los Angeles basin. This approach and its functionality are illustrated by investigating the variations of ground motions (e.g. peak ground velocity and synthetic seismograms) due to the source complexity. The source complexities are considered with two respects: hypocenter location and slip history. The results show a complex behavior, with dependence of absolute peak ground velocity and their variation on source process directionality, hypocenter location, local structure, and static slip asperity location. We concluded that combining effect due to 3-D structure and finite-source is necessary to quantify ground motion characteristics and their variations. Our results will facilitate the earthquake hazard assessment projects.

Wang, Haijiang; Igel, Heiner; Gallovic, Frantisek

2010-06-01

322

Ground deformation associated with post-mining activity at the French-German border revealed by novel InSAR time series method  

NASA Astrophysics Data System (ADS)

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 dewatering systems may come from this region. Providing that enough SAR data is available, this method opens new opportunities for detecting and locating man-made and natural ground deformation signals with high temporal resolution and precision.

Samsonov, Sergey; d'Oreye, Nicolas; Smets, Benoît

2013-08-01

323

Cross-Cultural Issues of Intra- and Inter-Organisational Cooperation in Space Operations: A Survey Study with Ground Personnel of the European Space Agency  

Microsoft Academic Search

Today's space operations often involve close co-working of people with different ethnical, professional and organizational backgrounds. The aim of the 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. Methods: A web-based survey was answered by 905 employees at the European Astronaut

Gro Mjeldheim Sandal; Dietrich Manzey

2008-01-01

324

Parabolic Wave Equation Method Applied to the Tropospheric Ducting Propagation Problem: A Survey  

Microsoft Academic Search

A survey is made of one of the most widely used approximation methods in the wave propagation studies—the parabolic wave equation method—applied for the specific case of microwave propagation assessment under tropospheric ducting conditions. A brief review of the methods for tropospheric refractivity profiling, the average refractivity modeling, and the applicability of the often-assumed lateral homogeneity of the refractivity is

I. Sirkova; M. Mikhalev

2006-01-01

325

Compilation of field methods used in geochemical prospecting by the U.S. Geological Survey  

USGS Publications Warehouse

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.

Lakin, Hubert William; Ward, Frederick Norville; Almond, Hy

1952-01-01

326

Advanced Grounding Methods in the Presence of Carbon Fibre Reinforced Plastic Structures  

NASA Astrophysics Data System (ADS)

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.

Leininger, M.; Thurecht, F.; Pfeiffer, E.; Ruddle, A.

2012-05-01

327

Determination of ground and excited state dipole moments of dipolar laser dyes by solvatochromic shift method.  

PubMed

The absorption and fluorescence spectra of three medium sized dipolar laser dyes: coumarin 478 (C478), coumarin 519 (C519) and coumarin 523 (C523) have been recorded and studied comprehensively in various solvents at room temperature. The absorption and fluorescence spectra of C478, C519 and C523 show a bathochromic and hypsochromic shifts with increasing solvent polarity indicate that the transitions involved are ???(?) and n??(?). Onsager radii determined from ab initio calculations were used in the determination of dipole moments. The ground and excited state dipole moments were evaluated by using solvatochromic correlations. It is observed that the dipole moment values of excited states (?e) are higher than corresponding ground state values (?g) for the solvents studied. The ground and excited state dipole moments of these probes computed from ab initio calculations and those determined experimentally are compared and the results are discussed. PMID:24394528

Patil, S K; Wari, M N; Panicker, C Yohannan; Inamdar, S R

2014-04-01

328

Methods of removing uranium from drinking water. 1. A literature survey. 2. Present municipal water treatment and potential removal methods  

Microsoft Academic Search

Literature was searched for methods of removing uranium from drinking water. U.S. manufacturers and users of water-treatment equipment and products were also contacted regarding methods of removing uranium from potable water. Based on the results of these surveys, it was recommended that untreated, partially treated, and finished water samples from municipal water-treatment facilities be analyzed to determine the extent of

J. S. Drury; D. Michelson; J. T. Ensminger; S. Y. Lee; S. K. White

1982-01-01

329

Continuous Audience Response Technology and Survey Methods: New Research Methods and an Application.  

ERIC Educational Resources Information Center

Speedback is a continuous audience response technology system that was used to test concepts and variable relationships that had been derived earlier from large-sample, survey research methodology. Continuous audience response technologies used computer hardware and customized software to collect subjects' reactions to stimuli, usually videotaped…

Long, Larry W.; And Others

330

Celestial Exoplanet Survey Occulter: A Concept for Direct Imaging of Extrasolar Earth-like Planets from the Ground  

NASA Astrophysics Data System (ADS)

We present a new concept for detecting and characterizing extrasolar planets down to Earth size or smaller through direct imaging. The New Worlds Observer (NWO) occulter developed by Cash and coworkers is placed in a particular geometrical setup in which fuel requirements are small and the occulter is used in combination with ground-based telescopes, presumably leading to an extreme cost efficiency compared to other concepts with similar science goals. We investigate the various aspects of the given geometry, such as the dynamics and radiation environment of the occulter, and construct a detailed example target list to ensure that an excellent science case can be maintained despite the limited sky coverage. It is found that more than 200 systems can be observed with two to three visits per system, using only a few tons of fuel. For each system, an Earth-sized planet with an Earth-like albedo can be found in the habitable zone in less than 2 hr.

Janson, M.

2007-02-01

331

surveys  

Microsoft Academic Search

SUMMARY Background Impetigo is a common skin infection in children. The epidemiology is relatively unknown, and the choice of treatment is subject to debate. Objective The objective of our study was to determine the incidence and treatment of impetigo in Dutch general practice, and to assess trends between 1987 and 2001. Methods We used data from the first (1987) and

S. Koning; R. S. A. MOHAMMEDAMIN; J. C. VAN DER WOUDEN; L. W. A. VAN SUIJLEKOM-SMIT; F. G. SCHELLEVIS; S. THOMAS

332

Detection of contaminant plumes in ground water of Long Island, New York, by electromagnetic terrain-conductivity surveys  

USGS Publications Warehouse

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)

Mack, T. J.; Maus, P. E.

1986-01-01

333

Ground penetrating radar survey finalized to the recovery of the ``S. Agata alla Badia'' church in Catania (eastern Sicily, Italy)  

NASA Astrophysics Data System (ADS)

Numerous archaeological sites dating to the greek-roman period have been found in the underground of the city of Catania (eastern Sicily, Italy). Their presence is a testimony of the several settlements that have followed in this area over time. In this work we have conducted electromagnetic surveys, consisting of ten georadar profiles, inside the church of “S. Agata alla Badia”, damaged during the earthquake occurred in eastern Sicily on 13 December 1990. The aim was to investigate the area where the church is located to obtain information useful for its structural recovery. Mechanical drillings were also carried out to reconstruct the local stratigraphy, which could be complicated by the presence of underground cavities and artefacts, as evidenced by recent excavations beneath the Catania Cathedral, in the nearby Piazza Duomo. From the interpretation of the GPR data, the presence of ancient masonry structures underlying the recent foundations was highlighted. In addition, the GPR survey allowed us to identify and locate reflective horizons in the subsurface, probably due to the presence of materials with different state of aggregation and/or to buried structures.

Imposa, S.; Barone, F.; Gresta, S.; Leone, A.

2009-08-01

334

3D temporal evolution and modeling of ground deformation recorded on Mt. Etna from the 2007 to 2008 through the SISTEM method  

NASA Astrophysics Data System (ADS)

A study of the ground deformation pattern of Mount Etna volcano, based on the results of the SISTEM (Simultaneous and Integrated Strain Tensor Estimation from geodetic and satellite deformation Measurements) integration method is reported. The SISTEM enables integrating geodetic in situ ground deformation measurements (GPS) with satellite interferometric measurements (ENVISAT), in order to obtain high resolution 3D displacement maps, allowing to overcome the limitations of each technique and take advantage of the particular features of each of them. In this work ground motion data provided by GPS surveys are integrated with the interferometric synthetic aperture radar (InSAR) Envisat data, collected from 2007 to 2008, to provide 3D displacements maps. We imaged the time evolution of ground displacement measured along the Line Of Sight (LOS) of the Envisat satellite for both ascending and descending Envisat geometries. The main deformation episode occurred on Mt. Etna during the 2007-2008 time period was the May 2008 dike intrusion and the following 2008-2009 eruption. It started on May 13th, 2008, with the opening of an eruptive fissure propagating inside the topographical depression of the Valle del Bove, where the lava flows expanded. The eruption produced a lava flow of about 6 Km length, and it was preceded and accompanied by strong seismic release, and lava fountaining activity. The 3D temporal evolution of ground deformation was analyzed in order to define the dynamics preceding and accompanying the onset of the 2008-2009 Mt. Etna eruption. In particular, this analysis reveals a slight inflation visible on the upper western side of the volcano in the pre-eruptive period (form June 2007 to May 2008) characterized by a small amplitude of the ground deformation, except on the eastern flank. Data inversions detected a pressurizing source located beneath the western flank of the volcano at a depth of about 3Km bsl. In the period encompassing the eruption onset, the main ground deformation occurred around the summit craters, in the nearby of the eruptive fissures. The displacement pattern reveals also a rapid decay of the deformation gradient with the altitude confirming the shallow depth of the intrusion. The northward dyke propagation, occurred after the beginning of the eruption, was well detected by the SISTEM integrated displacement maps; it was confirmed by on field structural surveys that revealed a dry fracture field, propagating from the summit area towards the NNW direction for about 2.5 km. The inversion results confirm a dike located under the vents of the eruption and extending towards NNW, westward dipping. In the post-intrusion period (from May to July 2008), a deflation of the volcano was detected, according to a depressurizing source, localized by data inversion, beneath the summit craters.

Bonforte, A.; Guglielmino, F.; Puglisi, G.

2012-04-01

335

A data input program (MFI2K) for the U.S. Geological Survey modular ground-water model (MODFLOW-2000)  

USGS Publications Warehouse

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.

Harbaugh, Arlen W.

2002-01-01

336

Development of optical ground verification method for mum to sub-mm reflectors  

Microsoft Academic Search

Large reflectors and antennas for the IR to mm wavelength range are being planned for many Earth observation and astronomical space missions and for commercial communication satellites as well. Scientific observatories require large telescopes with precisely shaped reflectors for collecting the electro-magnetic radiation from faint sources. The challenging tasks of on-ground testing are to achieve the required accuracy in the

Y. Stockman; C. Thizy; P. Lemaire; M. Georges; E. Mazy; A. Mazzoli; Y. Houbrechts; P. Rochus; S. Roose; D. Doyle; G. Ulbrich

2004-01-01

337

A Simple Method for Measuring Ground-Level Ozone in the Atmosphere  

ERIC Educational Resources Information Center

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…

Seeley, John V.; Seeley, Stacy K.; Bull, Arthur W.; Fehir, Richard J., Jr.; Cornwall, Susan; Knudsen, Gabriel A.

2005-01-01

338

Methods of Gas Phase Capture of Iodine from Fuel Reprocessing Off-Gas: A Literature Survey  

SciTech Connect

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.

Daryl Haefner

2007-02-01

339

A Field Test of Electromigration as a Method for Remediating Sulfate from Shallow Ground Water  

USGS Publications Warehouse

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.

Patterson, C. G.; Runnells, D. D.

1996-01-01

340

Detection of hotspots and rapid determination of methane emissions from landfills via a ground-surface method.  

PubMed

We present a method for the rapid determination of methane emissions from landfills based on atmospheric dispersion theory, which suggests that the methane concentration, at a small distance from the soil/atmosphere interface, is proportional to its flux. Thus, after suitable calibration, the determination of methane concentrations close to the ground allows for flux determination in a shorter time than with standard enclosure techniques. This concept was tested using a surface probe in direct contact with the ground. The probe extracts a continuous sample of the air at the probe/ground interface and transports it to a portable methane analyzer. It was observed that stable methane concentrations were measured 30 s after the probe was positioned at the measurement point. These concentrations correlated well with the fluxes measured by standard static chambers. The method was used to determine the fluxes at 217 points within a 90,000 m(2) landfill. These measurements facilitated mapping of the CH4 emissions and the localization of hotspots. We conclude that the method is simple, effective, and relatively quick, compared to existing standard methods. PMID:25399118

Gonzalez-Valencia, R; Magana-Rodriguez, F; Maldonado, E; Salinas, J; Thalasso, F

2015-01-01

341

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)

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, ?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.

Schmidt, Matthew; Constable, Steve; Ing, Christopher; Roy, Pierre-Nicholas

2014-06-01

342

A survey of tools and methods used by certified professional ergonomists.  

PubMed

A survey of Certified Professional Ergonomists (CPEs) was conducted to gather information on the types of basic tools, direct and observational measurement techniques, and software used by practitioners. The motivation for the survey was to better understand what types of tools and methods practitioners use, their opinions of these tools, and to potentially gain an understanding of the constraints or preferences that influence this selection. Reasons for using or not using a selection of tools were also surveyed. Of 578 surveys that were delivered to CPEs and Associate Ergonomics Professionals, 308 were returned for a response rate of 53%. The respondents tended to be biased towards physical ergonomics, as the survey primarily focused on this area of ergonomics. A high percentage of respondents reported using tape measures, video cameras, stopwatches and digital cameras. The most commonly used observational methods were those involving manual materials handling, whereas the most commonly used direct measurement tools were pinch and grip dynamometers and push/pull gauges. The frequency and type of checklists, software, and anthropometric data used are summarized. PMID:15892943

Dempsey, Patrick G; McGorry, Raymond W; Maynard, Wayne S

2005-07-01

343

Introduction to the U.S. Geological Survey National Water-Quality Assessment (NAWQA) of ground-water quality trends and comparison to other national programs.  

PubMed

Assessment of temporal trends in national ground-water quality networks are rarely published in scientific journals. This is partly due to the fact that long-term data from these types of networks are uncommon and because many national monitoring networks are not driven by hypotheses that can be easily incorporated into scientific research. The U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) since 1991 has to date (2006) concentrated on occurrence of contaminants because sufficient data for trend analysis is only just becoming available. This paper introduces the first set of trend assessments from NAWQA and provides an assessment of the success of the program. On a national scale, nitrate concentrations in ground water have generally increased from 1988 to 2004, but trends in pesticide concentrations are less apparent. Regionally, the studies showed high nitrate concentrations and frequent pesticide detections are linked to agricultural use of fertilizers and pesticides. Most of these areas showed increases in nitrate concentration within the last decade, and these increases are associated with oxic-geochemical conditions and well-drained soils. The current NAWQA plan for collecting data to define trends needs to be constantly reevaluated to determine if the approach fulfills the expected outcome. To assist this evaluation, a comparison of NAWQA to other national ground-water quality programs was undertaken. The design and spatial extent of each national program depend on many factors, including current and long-term budgets, purpose of the program, size of the country, and diversity of aquifer types. Comparison of NAWQA to nine other national programs shows a great diversity in program designs, but indicates that different approaches can achieve similar and equally important goals. PMID:18765765

Rosen, Michael R; Lapham, Wayne W

2008-01-01

344

Analysis of method of polarization surveying of water surface oil pollution  

NASA Technical Reports Server (NTRS)

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.

Zhukov, B. S.

1979-01-01

345

Randomized Inquiry vs. Conventional Questionnaire Method in Estimating Drug Usage Rates Through Mail Surveys.  

ERIC Educational Resources Information Center

This report is a product of research conducted under a program exploring improved methods of acquiring data on sensitive topics, such as the scope and intensity of current social problems. In this case, the problem studied was drug abuse in the Army. A mail survey dealing with illicit drug use was conducted, comparing the data acquisition…

Brown, George H.

346

A Survey of Analysis Models and Methods in Website Verification and Testing  

E-print Network

others are interested in dealing with static and dynamic behavior. In this paper, we attemptA Survey of Analysis Models and Methods in Website Verification and Testing Manar H. Alalfi, James and testing of websites requires effective modelling techniques that address the specific challenges of web

347

A Survey of Analysis Models and Methods in Website Verification and Testing  

Microsoft Academic Search

Models are considered an essential step in capturing dierent system behaviors and in simplifying any further analysis required to check or to improve the quality of software. Ver- ification and testing of web software requires eective modelling techniques that address the specific challenges of web applications. In this study we survey 21 dierent analysis mod- elling methods used in website

Manar H. Alalfi; James R. Cordy; Thomas R. Dean

2007-01-01

348

FALL DETECTION AND ACTIVITY RECOGNITION METHODS FOR THE CONFIDENCE PROJECT: A SURVEY  

E-print Network

tags obtained by motion capture system. 3 FALL DETECTION Falls among the elderly are the leading cause of injury, even death, and the loss of independent living. Detection and prevention of falls is consequentlyFALL DETECTION AND ACTIVITY RECOGNITION METHODS FOR THE CONFIDENCE PROJECT: A SURVEY Bostjan Kaluza

LuÂ?trek, Mitja

349

Four Methods of Handling Missing Data with the 1984 General Social Survey.  

ERIC Educational Resources Information Center

When survey data are statistically analyzed, many times some of the data is missing. If the missing values are not correctly handled, results of the analysis may be dubious and publication may jeopardize the credibility of the organization preparing the report. This study examined four of the more commonly used methods of handling missing data.…

Witta, Lea; Kaiser, Javaid

350

Airborne lidar surveys are an at-tractive alternative to the methods  

E-print Network

264 Airborne lidar surveys are an at- tractive alternative to the methods presentlyusedinfishery- veys is still in its infancy. Fish schools have been detected with a variety of lidar systems (Churnside and Hunter, 1996), but schools have never been systematically studied with lidar, nor has existing

351

Examining Stress in Graduate Assistants: Combining Qualitative and Quantitative Survey Methods  

ERIC Educational Resources Information Center

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…

Mazzola, Joseph J.; Walker, Erin J.; Shockley, Kristen M.; Spector, Paul E.

2011-01-01

352

A Survey of Classification Methods for Protein Domain Motions and Flexibility  

E-print Network

1 A Survey of Classification Methods for Protein Domain Motions and Flexibility David Parker the importance of structural flexibility of proteins for their function. The interface between protein domains, such as the flexibility properties of an intersubunit linker used in constructing an antibody [7]. The flexibility

353

A Survey on Sound Source Localization in Robotics: from Binaural to Array Processing Methods  

E-print Network

A Survey on Sound Source Localization in Robotics: from Binaural to Array Processing Methods S. A comprehensive review is proposed of recent robotics achievements, be they binaural or rooted in Array Processing and neurology of human hearing. Keywords: Robot audition, source localization, binaural audition, array

354

Survey of modelling methods for wind turbine wakes and wind farms  

Microsoft Academic Search

This article provides an overview and analysis of different wake-modelling methods which may be used as prediction and design tools for both wind turbines and wind farms. We also survey the available data concerning the measurement of wind magnitudes in both single wakes and wind farms, and of loading effects on wind turbines under single- and multiple-wake conditions. The relative

A. Crespo; J. Hernández; S. Frandsen

1999-01-01

355

Noise reduction in chaotic time-series data: A survey of common methods  

Microsoft Academic Search

This paper surveys some of the methods that have been suggested for reducing noise in time-series data whose underlying dynamical behavior can be characterized as low-dimensional chaos. Although the procedures differ in details, all of them must solve three basic problems: how to reconstruct an attractor from the data, how to approximate the dynamics in various regions on the attractor,

Eric J. Kostelich; Thomas Schreiber

1993-01-01

356

Survey of molecular methods for the typing of wine yeast strains  

Microsoft Academic Search

A survey of the genetic polymorphisms produced by distinct methods was performed in 23 commercial winery yeast strains. Microsatellite typing, using six different loci, an optimized interdelta sequence analysis and restriction fragment length polymorphism of mitochondrial DNA generated by the enzyme HinfI had the same discriminatory power: among the 23 commercial yeast strains, 21 distinct patterns were obtained. Karyotype analysis

Dorit Schuller; Eva Valero; Sylvie Dequin; Margarida Casal

2004-01-01

357

A Survey of Methods for Computing (un)Stable Manifolds of Vector Fields  

Microsoft Academic Search

The computation of global invariant manifolds has seen renewed interest in recent years. We survey dieren t approaches for computing a global stable or unstable mani- fold of a vector eld, where we concentrate on the case of a two-dimensional manifold. All methods are illustrated with the same example | the two-dimensional stable man- ifold of the origin in the

Bernd Krauskopf; Hinke M. Osinga; Eusebius J. Doedel; M. E. Henderson; John Guckenheimer; A. Vladimirsky; M. Dellnitz; O. Junge

2005-01-01

358

A SURVEY OF METHODS FOR COLOUR IMAGE INDEXING AND RETRIEVAL IN IMAGE DATABASES  

Microsoft Academic Search

Color is a feature of the great majority of content-based image retrieval systems. However the robustness, effectiveness, and efficiency of its use in image indexing are still open issues. This paper provides a comprehensive survey of the methods for color image indexing and retrieval described in the literature. In particular, image preprocessing, the features used to represent color information, and

Raimondo SCHETTINI; Gianluigi CIOCCA; Silvia ZUFFI

2001-01-01

359

Critical Survey of Hierarchical Methods for State Estimation of Electric Power Systems  

Microsoft Academic Search

This paper intends to give a unified survey of methods appropriate for solving the state estimation problem in large-scale electric power systems. After a first overview of the various approaches proposed up to now, the most suitable among them are described, examined and compared. The comparisons are carried out on the basis of selected criteria evolving estimation properties of the

T. Van Cutsem; M. Ribbens-Pavella

1983-01-01

360

A SURVEY OF EDDY CURRENT DISPLACEMENT SENSORS: IMPERFECTIONS AND SIGNAL CONDITIONING METHODS  

Microsoft Academic Search

In this paper, we focus on eddy current sensors (ECSs) as important candidates for measuring short-range displacements. First, the imperfections of these sensors are discussed, and then signal conditioning methods are addressed. The benefits and the drawbacks of each technique, which should be considered by the designer, have been mentioned. The focus of the survey is on high performance ECSs.

M. R. Nabavi; Stoyan Nihtianov Nihtianov

361

Exact ground state Monte Carlo method for Bosons without importance sampling.  

PubMed

Generally "exact" quantum Monte Carlo computations for the ground state of many bosons make use of importance sampling. The importance sampling is based either on a guiding function or on an initial variational wave function. Here we investigate the need of importance sampling in the case of path integral ground state (PIGS) Monte Carlo. PIGS is based on a discrete imaginary time evolution of an initial wave function with a nonzero overlap with the ground state, which gives rise to a discrete path which is sampled via a Metropolis-like algorithm. In principle the exact ground state is reached in the limit of an infinite imaginary time evolution, but actual computations are based on finite time evolutions and the question is whether such computations give unbiased exact results. We have studied bulk liquid and solid (4)He with PIGS by considering as initial wave function a constant, i.e., the ground state of an ideal Bose gas. This implies that the evolution toward the ground state is driven only by the imaginary time propagator, i.e., there is no importance sampling. For both phases we obtain results converging to those obtained by considering the best available variational wave function (the shadow wave function) as initial wave function. Moreover we obtain the same results even by considering wave functions with the wrong correlations, for instance, a wave function of a strongly localized Einstein crystal for the liquid phase. This convergence is true not only for diagonal properties such as the energy, the radial distribution function, and the static structure factor, but also for off-diagonal ones, such as the one-body density matrix. This robustness of PIGS can be traced back to the fact that the chosen initial wave function acts only at the beginning of the path without affecting the imaginary time propagator. From this analysis we conclude that zero temperature PIGS calculations can be as unbiased as those of finite temperature path integral Monte Carlo. On the other hand, a judicious choice of the initial wave function greatly improves the rate of convergence to the exact results. PMID:20568848

Rossi, M; Nava, M; Reatto, L; Galli, D E

2009-10-21

362

Survey of systems safety analysis methods and their application to nuclear waste management systems  

SciTech Connect

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.

Pelto, P.J.; Winegardner, W.K.; Gallucci, R.H.V.

1981-11-01

363

A survey of the methods used by farmers to castrate calves in New Zealand  

Microsoft Academic Search

Aims. To identify the methods used to castrate calves and the age at which castration is carried out on farms in New Zealand.Methods. A survey was carried out by questionnaire sent to the 14,000 recipients of “Meat Matters” produced by Meat New Zealand. The questionnaires on return were analysed on a national and regional basis.Results. Of the 3,788 respondents, 74%

K. J. Stafford; D. J. Mellor; C. M. McMeekan

2000-01-01

364

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)

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 by topography, near a gravity station. The acquired negative anomaly in the residual Bouguer anomalies field suggested the presence of possible void features. GPR and modelling data were used to estimate the depth and shape of the anomalous source.

Leucci, Giovanni; De Giorgi, Lara

2010-06-01

365

A ground state potential energy surface for H2 using Monte Carlo methods  

Microsoft Academic Search

Using variational Monte Carlo and a simple explicitly correlated wave function we have computed the Born–Oppenheimer energy of the H2 ground state (X 1?g+) at 24 internuclear distances. We have also calculated the diagonal correction to the Born–Oppenheimer approximation and the lowest-order relativistic corrections at each distance using variational Monte Carlo techniques. The nonadiabatic values are evaluated from numerical derivatives

S. A. Alexander; R. L. Coldwell

2004-01-01

366

A ground state potential energy surface for H2 using Monte Carlo methods  

Microsoft Academic Search

Using variational Monte Carlo and a simple explicitly correlated wave function we have computed the Born-Oppenheimer energy of the H2 ground state (X 1Sigmag+) at 24 internuclear distances. We have also calculated the diagonal correction to the Born-Oppenheimer approximation and the lowest-order relativistic corrections at each distance using variational Monte Carlo techniques. The nonadiabatic values are evaluated from numerical derivatives

S. A. Alexander; R. L. Coldwell

2004-01-01

367

A Method for Calculating the Probability of Successfully Completing a Rocket Propulsion Ground Test  

NASA Technical Reports Server (NTRS)

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.

Messer, Bradley

2007-01-01

368

A multireference perturbation method using non-orthogonal Hartree-Fock determinants for ground and excited states  

SciTech Connect

In this article we propose the ?SCF(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, ?SCF(2) employs a set of self-consistent Hartree-Fock determinants, also known as ?SCF states. Each ?SCF 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, ?SCF(2) treats the ground and excited state determinants even-handedly. We apply ?SCF(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 ?SCF states.

Yost, Shane R.; Kowalczyk, Tim; Van Voorhis, Troy, E-mail: tvan@mit.edu [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 (United States)

2013-11-07

369

Application of passive source surface-wave method in site engineering seismic survey  

NASA Astrophysics Data System (ADS)

Site engineering seismic survey provides basic data for seismic effect analysis. As an important parameter of soil, shear-wave velocity is usually obtained through wave velocity testing in borehole. In this paper, the passive source surface-wave method is introduced into the site engineering seismic survey and practically applied in an engineering site of Shijingshan District. By recording the ubiquitous weak vibration on the earth surface, extract the dispersion curve from the surface-wave components using the SPAC method and obtain the shear-wave velocity structure from inversion. Over the depth of 42 m underground, it totally consists of five layers with interface depth of 3.31, 4.50, 7.23, 17.41, and 42.00 m; and shear-wave velocity of 144.0, 198.3, 339.4, 744.2, and 903.7 m/s, respectively. The inversion result is used to evaluate site classification, determine the maximum shear modulus of soil, provide basis for further seismic hazard analysis and site assessment or site zoning, etc. The result shows that the passive source surface-wave method is feasible in the site engineering seismic survey and can replace boreholes, shorten survey period, and reduce engineering cost to some extent.

Wang, Chaofan; Zhang, Jian; Yan, Lihui; Liu, Hui; Zhao, Dong

2014-02-01

370

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

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.

Ikehara, M. E.; Phillips, S. P.

1994-01-01

371

Complementary methods of system usability evaluation: surveys and observations during software design and development cycles.  

PubMed

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

Horsky, Jan; McColgan, Kerry; Pang, Justine E; Melnikas, Andrea J; Linder, Jeffrey A; Schnipper, Jeffrey L; Middleton, Blackford

2010-10-01

372

The comparison of three methods for isolation of Arcobacter spp. in raw ground pork  

E-print Network

. The prevalence in pork has been found to be relatively low, typically 5%, using standard isolation methods. These methods include the deBoer method, Collins method and a modified version called the Direct Collins method. In this experiment, these broth and agar...

Ohlendorf, Dawn Suzanne

2012-06-07

373

Single-Event Effects Ground Testing and On-Orbit Rate Prediction Methods: The Past, Present and Future  

NASA Technical Reports Server (NTRS)

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.

Reed, Robert A.; Kinnison, Jim; Pickel, Jim; Buchner, Stephen; Marshall, Paul W.; Kniffin, Scott; LaBel, Kenneth A.

2003-01-01

374

Detecting population declines over large areas with presence-absence, time-to-encounter, and count survey methods.  

PubMed

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

Pollock, Jacob E

2006-06-01

375

A thermal profile method to identify potential ground-water discharge areas and preferred salmonid habitats for long river reaches  

USGS Publications Warehouse

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.

Vaccaro, J.J.; Maloy, K.J.

2006-01-01

376

Efficient and spectrally accurate numerical methods for computing ground and first excited states in Bose Einstein condensates  

NASA Astrophysics Data System (ADS)

In this paper, we present two efficient and spectrally accurate numerical methods for computing the ground and first excited states in Bose-Einstein condensates (BECs). We begin with a review on the gradient flow with discrete normalization (GFDN) for computing stationary states of a nonconvex minimization problem and show how to choose initial data effectively for the GFDN. For discretizing the gradient flow, we use sine-pseudospectral method for spatial derivatives and either backward Euler scheme (BESP) or backward/forward Euler schemes for linear/nonlinear terms (BFSP) for temporal derivatives. Both BESP and BFSP are spectral order accurate for computing the ground and first excited states in BEC. Of course, they have their own advantages: (i) for linear case, BESP is energy diminishing for any time step size where BFSP is energy diminishing under a constraint on the time step size; (ii) at every time step, the linear system in BFSP can be solved directly via fast sine transform (FST) and thus it is extremely efficient, and in BESP it needs to be solved iteratively via FST by introducing a stabilization term and thus it could be efficient too. Comparisons between BESP and BFSP as well as other existing numerical methods are reported in terms of accuracy and total computational time. Our numerical results show that both BESP and BFSP are much more accurate and efficient than those existing numerical methods in the literature. Finally our new numerical methods are applied to compute the ground and first excited states in BEC in one dimension (1D), 2D and 3D with a combined harmonic and optical lattice potential for demonstrating their efficiency and high resolution.

Bao, Weizhu; Chern, I.-Liang; Lim, Fong Yin

2006-12-01

377

Does survey method bias the description of northern goshawk nest-site structure?  

USGS Publications Warehouse

Past studies on the nesting habitat of northern goshawks (Accipiter gentilis) often relied on nests found opportunistically, either during timber-sale operations, by searching apparently 'good' goshawk habitat, or by other search methods where areas were preselected based on known forest conditions. Therefore, a bias in the characterization of habitat surrounding northern goshawk nest sites may exist toward late-forest structure (large trees, high canopy closure). This potential problem has confounded interpretation of data on nesting habitat of northern goshawks and added to uncertainty in the review process to consider the species for federal listing as threatened or endangered. Systematic survey methods, which strive for complete coverage of an area and often use broadcasts of conspecific calls, have been developed to overcome these potential biases, but no study has compared habitat characteristics around nests found opportunistically with those found systematically. We compared habitat characteristics in a 0.4-ha area around nests found systematically (n = 27) versus those found opportunistically (n = 22) on 3 national forests in eastern Oregon. We found that both density of large trees (systematic: x?? = 16.4 ?? 3.1 trees/ha; x?? ?? SE; opportunistic: x?? = 21.3 ?? 3.2; P = 0.56) and canopy closure (systematic: x?? = 72 ?? 2%; opportunistic: x?? = 70 ?? 2%; P = 0.61) were similar around nests found with either search method. Our results diminish concern that past survey methods mischaracterized northern goshawk nest-site structure. However, because northern goshawks nest in a variety of forest cover types with a wide range of structural characteristics, these results do not decrease the value of systematic survey methods in determining the most representative habitat descriptions for northern goshawks. Rigorous survey protocols allow repeatability and comparability of monitoring efforts and results over time.

Daw, S.K.; DeStefano, S.; Steidl, R.J.

1998-01-01

378

Application of ground water tracer methods in straddle packer testing at the ICPP, INEL  

SciTech Connect

The State Oversight Program's straddle packer sampling system was tested at the Idaho National Engineering Laboratory during July--September, 1992, in USGS monitoring well No. 44. The straddle packer was designed for the Oversight Program's ground water research program, to provide a means of characterizing the vertical hydraulic and water quality variations believed to exist in the eastern Snake River Plain aquifer beneath the Idaho National Engineering Laboratory. During the field program, tracer introduction and recovery experiments were conducted to evaluate QA sampling objectives as well as to assess the feasibility of obtaining additional information on aquifer/borehole characteristics such as specific discharge through different aquifer zones, integrity of packer seals, etc. A total of twelve tracer tests were performed on six different intervals from 467 to 600 feet below land surface (ft bls). Lithium bromide powder dissolved in de-ionized water was used as a tracer. All tracer tests were conducted in two phases: Emplacement -- introduction of a slug of a known quantity of tracer, followed by continuous mixing within the test interval for periods ranging from 8 to 72 minutes (without pumping to surface), during which time the tracer was diluted by ground water advection through the test interval; and recovery - pumping of the test interval to withdraw tracer from the borehole interval and the adjacent aquifer. Once tracer recovery had been completed, water quality sampling could be initiated, with the degree of interval purging having been defined by the degree of tracer recovery.

Welhan, J. (Geological Survey, Idaho Falls, ID (United States)); Fromm, J.; McCurry, M. (Idaho State Univ., Pocatello, ID (United States). Dept. of Geology)

1993-01-01

379

Application of ground water tracer methods in straddle packer testing at the ICPP, INEL  

SciTech Connect

The State Oversight Program`s straddle packer sampling system was tested at the Idaho National Engineering Laboratory during July--September, 1992, in USGS monitoring well No. 44. The straddle packer was designed for the Oversight Program`s ground water research program, to provide a means of characterizing the vertical hydraulic and water quality variations believed to exist in the eastern Snake River Plain aquifer beneath the Idaho National Engineering Laboratory. During the field program, tracer introduction and recovery experiments were conducted to evaluate QA sampling objectives as well as to assess the feasibility of obtaining additional information on aquifer/borehole characteristics such as specific discharge through different aquifer zones, integrity of packer seals, etc. A total of twelve tracer tests were performed on six different intervals from 467 to 600 feet below land surface (ft bls). Lithium bromide powder dissolved in de-ionized water was used as a tracer. All tracer tests were conducted in two phases: Emplacement -- introduction of a slug of a known quantity of tracer, followed by continuous mixing within the test interval for periods ranging from 8 to 72 minutes (without pumping to surface), during which time the tracer was diluted by ground water advection through the test interval; and recovery - pumping of the test interval to withdraw tracer from the borehole interval and the adjacent aquifer. Once tracer recovery had been completed, water quality sampling could be initiated, with the degree of interval purging having been defined by the degree of tracer recovery.

Welhan, J. [Geological Survey, Idaho Falls, ID (United States); Fromm, J.; McCurry, M. [Idaho State Univ., Pocatello, ID (United States). Dept. of Geology

1993-05-01

380

Method and Apparatus for Monitoring of Daily Activity in Terms of Ground Reaction Forces  

NASA Technical Reports Server (NTRS)

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.

Whalen, Robert T. (Inventor); Breit, Gregory A. (Inventor)

2001-01-01

381

Methods for implementing a medicine outlet survey: lessons from the anti-malarial market  

PubMed Central

Background In recent years an increasing number of public investments and policy changes have been made to improve the availability, affordability and quality of medicines available to consumers in developing countries, including anti-malarials. It is important to monitor the extent to which these interventions are successful in achieving their aims using quantitative data on the supply side of the market. There are a number of challenges related to studying supply, including outlet sampling, gaining provider cooperation and collecting accurate data on medicines. This paper provides guidance on key steps to address these issues when conducting a medicine outlet survey in a developing country context. While the basic principles of good survey design and implementation are important for all surveys, there are a set of specific issues that should be considered when conducting a medicine outlet survey. Methods This paper draws on the authors’ experience of designing and implementing outlet surveys, including the lessons learnt from ACTwatch outlet surveys on anti-malarial retail supply, and other key studies in the field. Key lessons and points of debate are distilled around the following areas: selecting a sample of outlets; techniques for collecting and analysing data on medicine availability, price and sales volumes; and methods for ensuring high quality data in general. Results and conclusions The authors first consider the inclusion criteria for outlets, contrasting comprehensive versus more focused approaches. Methods for developing a reliable sampling frame of outlets are then presented, including use of existing lists, key informants and an outlet census. Specific issues in the collection of data on medicine prices and sales volumes are discussed; and approaches for generating comparable price and sales volume data across products using the adult equivalent treatment dose (AETD) are explored. The paper concludes with advice on practical considerations, including questionnaire design, field worker training, and data collection. Survey materials developed by ACTwatch for investigating anti-malarial markets in sub-Saharan Africa and Asia provide a helpful resource for future studies in this area. PMID:23383972

2013-01-01

382

Multidisciplinary teams, and parents, negotiating common ground in shared-care of children with long-term conditions: A mixed methods study  

PubMed Central

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, and may help them to negotiate with parents and accelerate parents’ learning about shared caring. Our methodology and results are potentially transferrable to shared management of other conditions. PMID:23835151

2013-01-01

383

Health Risks from Exposures to Asbestos, Metals, and Various Chemicals due to Collapse of the World Trade Center: An Environmental Residential Survey with a Commentary Related to Ground Zero Workers  

Microsoft Academic Search

Environmental monitoring was immediately instituted at Ground Zero (GZ) after the collapse of the World Trade Center (WTC). However, nearby residences were not assessed. To address this, a GZ elected official task force requested an independent residential survey to be done. Its findings, whilst based upon relatively few samples, are still probably the first and most detailed produced to date.

E. B. Ilgren

2001-01-01

384

Study on the Technology and Method of Land Cover Classification for Geographic National Conditions Surveying  

NASA Astrophysics Data System (ADS)

Land Cover is the basis of geographic national conditions monitoring, extracting land cover information timely and accurately has become one of important tasks in the geographic national conditions surveying project. For the current situation of complex land cover type and large amount of data, there has emerged various new classification techniques and methods. However, the big difficult of classification?the large amount of data, the heavy workload of post-editing and other factors have seriously hampered the progress of the project. In this paper, it chooses high-resolution remote sensing image as original data, comprehensivly elaborates present research situation of oriented land cover classification. By the systematical analysis and summary of the basic and key problems of the land cover classification technology, relying on the geographic national information classification and standard system, discusses the available methods preliminarily to improve the accuracy of land cover classification which based on geographic national conditions surveying.

Jia, Y.; Li, H. T.; Gu, H. Y.; Han, Y. S.

2013-07-01

385

New Statistical Methods for Analysis of Large Surveys: Distributions and Correlations  

E-print Network

The aim of this paper is to describe new statistical methods for determination of the correlations among and distributions of physical parameters from a multivariate data with general and arbitrary truncations and selection biases. These methods, developed in collaboration with B. Efron of Department of Statistics at Stanford, can be used for analysis of combined data from many surveys with different and varied observational selection criteria. For clarity we will use the luminosity function of AGNs and its evolution to demonstrate the methods. We will first describe the general features of data truncation and present a brief review of past methods of analysis. Then we will describe the new methods and results from simulations testing their accuracy. Finally we will present the results from application of the methods to a sample of quasars.

Vahe' Petrosian

2001-12-19

386

Ground Water Recharge Estimation Using Water Table Fluctuation Method And By GIS Applications  

NASA Astrophysics Data System (ADS)

Quite often it has become a debating point that how much recharge is occurring to the groundwater table through rainfall on one hand and through recharge structures such as percolation ponds and checkdams on the other. In the present investigations Musi basin of Andhra Pradesh, India is selected for study during the period 2005-06. Pre-monsoon and Post-monsoon groundwater levels are collected through out the Musi basin at 89 locations covering an area11, 291.69 km2. Geology of the study area and rainfall data during the study period has been collected. The contour maps of rainfall and the change in groundwater level between Pre-monsoon and Post- monsoon have been prepared. First the change in groundwater storage is estimated for each successive strips of areas enclosed between two contours of groundwater level fluctuations. In this calculation Specific yield (Sy) values are adopted based on the local Geology. Areas between the contours are estimated through Arc GIS software package. All such storages are added to compute the total storage for the entire basin. In order to find out the percent of rainfall converted into groundwater storage as well as to find out the ground water recharge due to storageponds, a contour map of rainfall for the study area is prepared and areas between successive contours have been calculated. Based on the Geology map, Infiltration values are adopted for each successive strip of the contour area. Then the amount of water infiltrated into the ground is calculated by adjusting the infiltration values for each strip, so that the total infiltrated water for the entire basin is matched with change in Ground water storage, which is 1314.37 MCM for the upper Musi basin while it is 2827.29 MCM for entire Musi basin. With this procedure on an average 29.68 and 30.66 percent of Rainfall is converted into Groundwater recharge for Upper Musi and for entire Musi basin respectively. In the total recharge, the contribution of rainfall directly to Groundwater recharge is 8.53 and 8.81 percent and the remaining 21.15 and 21.85 percent is due to groundwater recharge from water conservation structures such as check dams, contour bunds, tanks, etc. for Upper Musi and for entire Musi basin respectively. The difference is attributable to the canal recharge in the case of Lower Musi. Therefore the Upper Musi values may be taken as a percent of Rainfall that is converted into Groundwater recharge.

Vajja, V.; Bekkam, V.; Nune, R.; M. v. S, R.

2007-05-01

387

Survey of artificial intelligence methods for detection and identification of component faults in nuclear power plants  

Microsoft Academic Search

A comprehensive survey of computer-based systems that apply artificial intelligence methods to detect and identify component faults in nuclear power plants is presented. Classification criteria are established that categorize artificial intelligence diagnostic systems according to the types of computing approaches used (e.g., computing tools, computer languages, and shell and simulation programs), the types of methodologies employed (e.g., types of knowledge,

Reifman

1997-01-01

388

The 2005 Chios ancient shipwreck survey: New methods for underwater archaeology  

Microsoft Academic Search

In 2005 a Greek and American interdisciplinary team investigated two shipwrecks off the coast of Chios dating to the 4th-century b.c. and the 2nd\\/1st century. The project pioneered archaeological methods of precision acoustic, digital image, and chemical survey using an autonomous underwater vehicle (AUV) and in-situ sensors, increasing the speed of data acquisition while decreasing costs. The AUV recorded data

Brendan P. Foley; Katerina DellaPorta; Dimitris Sakellariou; Brian S. Bingham; Richard Camilli; Ryan M. Eustice; Dionysis Evagelistis; Vicki L. Ferrini; Kostas Katsaros; Dimitris Kourkoumelis; Aggelos Mallios; Paraskevi Micha; David A. Mindell; Christopher Roman; Hanumant Singh; David S. Switzer; Theotokis Theodoulou

2009-01-01

389

SURVEY METHODS TO DETERMINE THE DISTRIBUTION AND INTENSITY OF DWARF MISTLETOES ^  

E-print Network

Abstract: Dwarf mistletoe distribution and intensity must be known to determine feasibility and priority of control measures. Surveys range from a quick estimate included in a general stand examination to a thorough investigation with large-scale maps. Accuracy and precision needed for management decisions will dictate which method to use. The 6-class system for rating dwarf mistletoe intensity is currently the best available for general use.

Oscar J. Dooling L

390

Classifying people by social class in population based health surveys: Two methods compared  

Microsoft Academic Search

Aims: In this study we evaluate the accuracy of a reclassification from a 10-category questionnaire-based occupational classification used in health surveys into the Erikson Goldthorpe Portocarero (EGP) social class scheme, by comparing it to the standard procedure based on occupational codes. Comparisons are based on socioeconomic inequalities in self-rated health. Methods: Individual data on occupation and health in a Norwegian

Steinar Krokstad; Kristen Ringdal; Steinar Westin

391

An Internet-based survey method for college student drinking research  

Microsoft Academic Search

The purpose of this study was to describe and assess the utility of an Internet-based survey method for characterizing the alcohol consumption of college students. After extensive pilot research, a random sample of 1910 students aged 16–29 years was invited to complete a questionnaire, consisting of a series of web-pages linked to a relational database on a secure web-site. A

Kypros Kypri; Stephen J. Gallagher; Martine L. Cashell-Smith

2004-01-01

392

Multi-determinant electron-nuclear quantum Monte Carlo method for ground state solution of molecular Hamiltonian  

NASA Astrophysics Data System (ADS)

The focus of this work is to obtain the ground state energy of the non-relativistic spin-independent molecular Hamiltonian without making the Born-Oppenheimer (BO) approximation. In addition to avoiding the BO approximation, this approach avoids imposing separable-rotor and harmonic oscillator approximations. The ground state solution is obtained variationally using multi-determinant variational Monte Carlo method where all nuclei and electrons in the molecule are treated quantum mechanically. The multi-determinant VMC provides the right framework for including explicit correlation in a multi-determinant expansion. This talk will discuss the construction of the basis functions and optimization of the variational coefficient. The electron-nuclear VMC method will be applied to H2, He2 and H2O and comparison of the VMC results with other methods will be presented. The results from these calculations will provide the necessary benchmark values that are needed in development of other multicomponent method such as electron-nuclear DFT and electron-nuclear FCIQMC.

Sambasivam, Abhinanden; Elward, Jennifer; Chakraborty, Arindam

2013-03-01

393

Grounding electrode and method of reducing the electrical resistance of soils  

DOEpatents

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.

Koehmstedt, Paul L. (Richland, WA)

1980-01-01

394

Evaluation of preservation methods for selected nutrients in ground water at the Idaho National Engineering Laboratory, Idaho  

SciTech Connect

Water from 28 wells completed in the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL) was sampled as part of the US Geological Survey`s quality-assurance program to determine the effect of different preservation methods on nutrient concentrations. Samples were preserved with filtration and with mercuric chloride and chilling, chilling only, or sulfuric acid and chilling. The samples were analyzed for ammonia, nitrite, nitrite plus nitrate, and orthophosphate by the US Geological Survey National Water Quality Laboratory. The study was done in cooperation with the US Department of Energy. The comparison between samples preserved with mercuric chloride and chilling and samples preserved by chilling only showed that all sample pairs were in statistical agreement. Results for ammonia and nitrite plus nitrate samples preserved with sulfuric acid and chilling were within the 95 percent confidence level of the results for the samples preserved by the other two methods and can be considered equivalent to them. Results of this study indicate that discontinuing the use of mercuric chloride as a preservation method for nutrients in water samples will not affect the comparability of data collected at the INEL before and after October 1, 1994.

Bartholomay, R.C.; Williams, L.M.

1996-10-01

395

Basis and methods of NASA airborne topographic mapper lidar surveys for coastal studies  

USGS Publications Warehouse

This paper provides an overview of the basic principles of airborne laser altimetry for surveys of coastal topography, and describes the methods used in the acquisition and processing of NASA Airborne Topographic Mapper (ATM) surveys that cover much of the conterminous US coastline. This form of remote sensing, also known as "topographic lidar", has undergone extremely rapid development during the last two decades, and has the potential to contribute within a wide range of coastal scientific investigations. Various airborne laser surveying (ALS) applications that are relevant to coastal studies are being pursued by researchers in a range of Earth science disciplines. Examples include the mapping of "bald earth" land surfaces below even moderately dense vegetation in studies of geologic framework and hydrology, and determination of the vegetation canopy structure, a key variable in mapping wildlife habitats. ALS has also proven to be an excellent method for the regional mapping of geomorphic change along barrier island beaches and other sandy coasts due to storms or long-term sedimentary processes. Coastal scientists are adopting ALS as a basic method in the study of an array of additional coastal topics. ALS can provide useful information in the analysis of shoreline change, the prediction and assessment of landslides along seacliffs and headlands, examination of subsidence causing coastal land loss, and in predicting storm surge and tsunami inundation.

Brock, John C.; Wright, C. Wayne; Sallenger, Asbury H.; Krabill, William B.; Swift, Robert N.

2002-01-01

396

Novel survey method finds dramatic decline of wild cotton-top tamarin population  

PubMed Central

The cotton-top tamarin (Saguinus oedipus) is a critically endangered primate, endemic to the tropical forests of Colombia. Population monitoring is essential to evaluate the success of conservation efforts, yet standard survey methods are ineffective because animals flee silently before they are seen. We developed a novel technique that combines the use of playbacks of territorial vocalizations with traditional transect surveys. We used remote sensing to identify potential habitat within the species' historic range, and visited the 27% that we could survey safely. Of this, only 99 km2 was extant forest, containing an estimated 2,045 animals (95% confidence interval 1,587–2,634). Assuming comparable densities in non-surveyed areas, approximately 7,394 wild cotton-top tamarins remain in Colombia. With 20–30,000 animals exported to the United States in the late 1960s, this must represent a precipitous decline. Habitat destruction and capture for the illegal pet trade are ongoing. Urgent conservation measures are required to prevent extinction in the wild. PMID:20975684

Savage, Anne; Thomas, Len; Leighty, Katherine A.; Soto, Luis H.; Medina, Felix S.

2010-01-01

397

Is the simple auger coring method reliable for below-ground standing biomass estimation in Eucalyptus forest plantations?  

PubMed Central

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:21572093

Levillain, Joseph; Thongo M'Bou, Armel; Deleporte, Philippe; Saint-Andre, Laurent; Jourdan, Christophe

2011-01-01

398

Integration of infrared thermography and high-frequency electromagnetic methods in archaeological surveys  

NASA Astrophysics Data System (ADS)

An integration of high-resolution non-destructive techniques is presented for the inspection and evaluation of ancient architectonic structures. Infrared thermography (IRT) represents a valuable tool for nondestructive evaluation of architectonic structures and artworks because it is capable of giving indications about most of the degradation sources of artworks and buildings of both historical interest and civil use. In particular, it is possible to detect cracks, disbondings, alteration of material consistency, etc. Indeed, by choosing the most adequate thermographic technique, it is possible to monitor the conservation state of artworks in time and to detect the presence of many types of defects (e.g., voids, cracks, disbondings, etc.) in different types of materials (e.g., concrete, masonry structures, bronze, etc.). The main advantages of infrared thermography when dealing with precious artworks may be summarized with three words: non-contact, non-invasive, and two-dimensionality. It is possible to inspect either a large surface such as the facade of a palace, or a very small surface of only few square millimetres. Conversely, the inspection depth is quite small; generally, of the order of centimetres. However, as demonstrated in previous work, IRT well matches with electric-and electromagnetic-type geophysical methods to characterize the overlapping zone from low-to-high depth in masonry structures. In particular, the use of high-frequency electromagnetic techniques, such as the ground penetrating radar (GPR), permits to reach investigation depths of some ten of centimetres by choosing appropriate frequencies of the transmitted electromagnetic signal. In the last decade a large utilisation of the GPR methodology to non-destructive analysis of engineering and architectural materials and structures has been experienced. This includes diverse features, such as definition of layer thickness, characterisation of different constructive materials, identification of voids and/or degraded zones, water content mapping, location of reinforcing bars and metal elements in concrete structures. The attention of this work is focused on the integration of both techniques for inspection of architectonic structures. First, an integration of techniques is performed in laboratory by considering an ad hoc specimen with insertion of anomalies. Then, the techniques are used for the inspection in situ of some important Italian archaeological sites, such as Pompei (Naples) and Nora (Cagliari). In the first site, the exploration is devoted to the analysis of wall decoration of the architectonical complex of Villa Imperiale with the aim to support the hypothesis that attributes the Villa to Imperial property as well as to evaluate the state of conservation of frescoes and underneath structure. As main findings, the applied techniques allows for detection of hidden previous decorative layers and for discrimination of different types of paint used as well as for identification of areas damaged by ingression in-depth of moisture and/or by disaggregation of the constituent materials. In the archaeological area of Nora, instead, the prospecting is devised to the evaluation of the state of degradation of two significant buildings of the ancient site: the temple and the theatre. Due to the very high horizontal and vertical resolution of the performed surveys, detailed physical anomaly maps of the investigated structures are obtained. Large portions of the masonry walls appear interested by decomposition of the mortar binding the stone blocks, which sometimes propagates along the whole stone wall. The information coming from a joint interpretation of IRT and GPR data allows detailed 3D images of the two investigated buildings, which are useful for future restoration planning.

di Maio, Rosa; Meola, Carosena; Fedi, Maurizio; Carlomagno, Giovanni Maria

2010-05-01

399

Comparative studies of water turbidity on the grounds of a nephelometric method and diffraction effects  

Microsoft Academic Search

Water turbidity may be examined by measuring the scattered light intensity by suspended particles in comparison with the scattered light intensity in pattern solution that states for a nephelometric method. Water turbidity may be also measured with the use of monochromatic light beam absorption. But a diffraction method has found the broadest use. The method uses indicatrix of scattering as

Józef Kirkiewicz; Barbara Pawlak; Bohdan Bieg; Ryszard Pikula; Piotr Treichel; Bozena Miklaszewicz; Jadwiga Mrozek-Lejman

2007-01-01

400

A method of increasing the sensitivity of protection from single-phase short-circuits to ground in the 6 - 10 kV network  

SciTech Connect

A method of increasing the sensitivity of protection from single-phase short-circuits to ground by acting on the signal with brief dummy grounding of the neutral is described. After determining the damage, the neutral is again grounded through a high resistance and an arc-quenching reactor. An increase in the protection sensitivity is thereby obtained, the damage detection time is shortened, and the probability of the single-phase short-circuit to ground converting into double and multipoint earth faults is reduced.

Manilov, A. M.; Mel'nik, D. A. [PC 'MC 'Metropoliya' (Ukraine)

2012-07-15

401

Use of High Fidelity Methods in Multidisciplinary Optimization-A Preliminary Survey  

NASA Technical Reports Server (NTRS)

Multidisciplinary optimization is a key element of design process. To date multidiscipline optimization methods that use low fidelity methods are well advanced. Optimization methods based on simple linear aerodynamic equations and plate structural equations have been applied to complex aerospace configurations. However, use of high fidelity methods such as the Euler/ Navier-Stokes for fluids and 3-D (three dimensional) finite elements for structures has begun recently. As an activity of Multidiscipline Design Optimization Technical Committee (MDO TC) of AIAA (American Institute of Aeronautics and Astronautics), an effort was initiated to assess the status of the use of high fidelity methods in multidisciplinary optimization. Contributions were solicited through the members MDO TC committee. This paper provides a summary of that survey.

Guruswamy, Guru P.; Kwak, Dochan (Technical Monitor)

2002-01-01

402

Indications and organisational methods for autologous blood transfusion procedures in Italy: results of a national survey  

PubMed Central

Introduction Pre-operative donation of autologous blood is a practice that is now being abandoned. Alternative methods of transfusing autologous blood, other than predeposited blood, do however play a role in limiting the need for transfusion of allogeneic blood. This survey of autologous blood transfusion practices, promoted by the Italian Society of Transfusion Medicine and Immunohaematology more than 2 years after the publication of national recommendations on the subject, was intended to acquire information on the indications for predeposit in Italy and on some organisational aspects of the alternative techniques of autotransfusion. Materials and methods A structured questionnaire consisting of 22 questions on the indications and organisational methods of autologous blood transfusion was made available on a web platform from 15 January to 15 March, 2013. The 232 Transfusion Services in Italy were invited by e-mail to complete the online survey. Results Of the 232 transfusion structures contacted, 160 (69%) responded to the survey, with the response rate decreasing from the North towards the South and the Islands. The use of predeposit has decreased considerably in Italy and about 50% of the units collected are discarded because of lack of use. Alternative techniques (acute isovolaemic haemodilution and peri-operative blood salvage) are used at different frequencies across the country. Discussion The data collected in this survey can be considered representative of national practice; they show that the already very limited indications for predeposit autologous blood transfusion must be adhered to even more scrupulously, also to avoid the notable waste of resources due to unused units. Users of alternative autotransfusion techniques must be involved in order to gain a full picture of the degree of use of such techniques; multidisciplinary agreement on the indications for their use is essential in order for these indications to have an effective role in “patient blood management” programmes. PMID:25350961

Catalano, Liviana; Campolongo, Alessandra; Caponera, Maurizio; Berzuini, Alessandra; Bontadini, Andrea; Furlo, Giuseppe; Pasqualetti, Patrizio; Liumbruno, Giancarlo M.

2014-01-01

403

A Survey Method for Characterizing Daily Life Experience: The Day Reconstruction Method  

Microsoft Academic Search

The Day Reconstruction Method (DRM) assesses how people spend their time and how they experience the various activities and settings of their lives, combining features of time-budget measurement and experience sampling. Participants systematically reconstruct their activities and experiences of the preceding day with procedures designed to reduce recall biases. The DRM's utility is shown by documenting close correspondences between the

Daniel Kahneman; Alan B. Krueger; David A. Schkade; Norbert Schwarz; Arthur A. Stone

2004-01-01

404

Comparison of ground-based measurements of natural radiation to airborne radiation survey data on transects from coastal California to the Colorado Plateau  

NASA Astrophysics Data System (ADS)

Natural gamma radiation measurements were collected with a hand-held Geiger counter at nearly 400 locations on two general transects across the southwestern United States. The data are used to provide ground-truth comparison to published airborne radiation surveys of the region. The first transect was collected by high school students in the SF-ROCKS program at San Francisco State University in the summer of 2008 starting in San Francisco. Data were collected across the Sierra Nevada Range on I-80, and across Highway 50 in Nevada, and I-70 in Utah. Data were collected in and around Great Basin, Arches, Capitol Reef, Bryce, and Zion National Parks, and Grand Staircase-Escalante National Monument. A second transect extends from San José, California to Flagstaff, Arizona and includes the Mojave National Reserve, Death Valley region, and locations throughout the Navajo Reservation region in northern Arizona and western New Mexico. Radiation data (with GPS reference) were collected from all the major sedimentary rock formations and igneous rocks of the Colorado Plateau and from many igneous and metamorphic rocks throughout the Great Basin and southern California deserts. Anomalously high localized levels were noted in selected sedimentary units associated with uranium exploration targets in the Colorado Plateau region, and in caverns and rock fissures where radon gas (and accumulation of derivative fission products) are the inferred sources.

Stoffer, P. W.; Hernández, L.; Messina, P.; Dearaujo, J.; Li, A.; Hicks, A.; White, L.

2008-12-01

405

Method and basis set dependence of anharmonic ground state nuclear wave functions and zero-point energies: Application to SSSH  

NASA Astrophysics Data System (ADS)

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.

Kolmann, Stephen J.; Jordan, Meredith J. T.

2010-02-01

406

Method and basis set dependence of anharmonic ground state nuclear wave functions and zero-point energies: application to SSSH.  

PubMed

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

Kolmann, Stephen J; Jordan, Meredith J T

2010-02-01

407

Application of classification-tree methods to identify nitrate sources in ground water  

USGS Publications Warehouse

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.

Spruill, T. B.; Showers, W. J.; Howe, S. S.

2002-01-01

408

ABSOLUTE MEASUREMENTS OF SOIL AND GROUND DENISTY BY THE GAMMASCOPIC METHOD  

Microsoft Academic Search

The use of the transmission gamma-beam method (gammascopic method) makes ; possible the prompt determinalion of soil density in situ without disturbing soil ; structure. When Geiger-Muller counters are used for detecting radiation, they ; must be calibrated, since variations in measurement and calibration conditions ; lead to errors. Using scintillation counters it is possible to exclude detection ; of

Nesterov

1959-01-01

409

A non-destructive method for estimating above-ground forest biomass in threatened woodlands  

Microsoft Academic Search

Current techniques for calculation of biomass in agroforestry require felling of many trees. Such methods are not well suited to the natural environment, especially if the environment is subject to anthropic degradation and if the wood supply to local populations is at stake. The method we describe here was used in a socioeconomic and ecological study of the biomass of

N. Montès; T. Gauquelin; W. Badri; V. Bertaudière; El H. Zaoui

2000-01-01

410

A survey method for characterizing daily life experience: the day reconstruction method.  

PubMed

The Day Reconstruction Method (DRM) assesses how people spend their time and how they experience the various activities and settings of their lives, combining features of time-budget measurement and experience sampling. Participants systematically reconstruct their activities and experiences of the preceding day with procedures designed to reduce recall biases. The DRM's utility is shown by documenting close correspondences between the DRM reports of 909 employed women and established results from experience sampling. An analysis of the hedonic treadmill shows the DRM's potential for well-being research. PMID:15576620

Kahneman, Daniel; Krueger, Alan B; Schkade, David A; Schwarz, Norbert; Stone, Arthur A

2004-12-01

411

Statistical Methods for Detecting Stellar Occultations by Kuiper Belt Objects: the Taiwanese-American Occultation Survey  

E-print Network

The Taiwanese-American Occultation Survey (TAOS) will detect objects in the Kuiper Belt, by measuring the rate of occultations of stars by these objects, using an array of three to four 50cm wide-field robotic telescopes. Thousands of stars will be monitored, resulting in hundreds of millions of photometric measurements per night. To optimize the success of TAOS, we have investigated various methods of gathering and processing the data and developed statistical methods for detecting occultations. In this paper we discuss these methods. The resulting estimated detection efficiencies will be used to guide the choice of various operational parameters determining the mode of actual observation when the telescopes come on line and begin routine observations. In particular we show how real-time detection algorithms may be constructed, taking advantage of having multiple telescopes. We also discuss a retrospective method for estimating the rate at which occultations occur.

Chyng-Lan Liang; John A. Rice; Imke de Pater; Charles Alcock; Tim Axelrod; Andrew Wang

2002-09-24

412

A non-destructive method for estimating above-ground forest biomass in threatened woodlands  

Microsoft Academic Search

Abstract Current techniques for calculation of biomass,in agroforestry require felling of many,trees. Such methods,are not well suited to the natural environment, especially if the environment is subject to anthropic degradation and if the wood supply to local populations is at stake. The method,we describe here was used in a socioeconomic,and ecological study of the biomass of a thuriferous juniper woodland,(Juniperus

N. Monte S; T. Gauquelin; V. Bertaudie Re; El H. Zaoui

413

Teaching Intercultural Communication in a Basic Technical Writing Course: A Survey of Our Current Practices and Methods  

ERIC Educational Resources Information Center

This research article reports the results of an online survey distributed among technical writing instructors in 2006. The survey aimed to examine how we teach intercultural communication in basic technical writing courses: our current practices and methods. The article discusses three major challenges that instructors may face when teaching about…

Matveeva, Natalia

2008-01-01

414

Grid-Search Location Methods for Ground-Truth Collection From Local and Regional Seismic Networks  

SciTech Connect

This project investigated new techniques for improving seismic event locations derived from regional and local networks. The technqiues include a new approach to empirical travel-time calibration that simultaneously fits data from multiple stations and events, using a generalization of the kriging method, and predicts travel-time corrections for arbitrary event-station paths. We combined this calibration approach with grid-search event location to produce a prototype new multiple-event location method that allows the use of spatially well-distributed events and takes into account correlations between the travel-time corrections from proximate event-station paths. Preliminary tests with a high quality data set from Nevada Test Site explosions indicated that our new calibration/location method offers improvement over the conventional multiple-event location methods now in common use, and is applicable to more general event-station geometries than the conventional methods. The tests were limited, however, and further research is needed to fully evaluate, and improve, the approach. Our project also demonstrated the importance of using a realistic model for observational errors in an event location procedure. We took the initial steps in developing a new error model based on mixture-of-Gaussians probability distributions, which possess the properties necessary to characterize the complex arrival time error processes that can occur when picking low signal-to-noise arrivals. We investigated various inference methods for fitting these distributions to observed travel-time residuals, including a Markov Chain Monte Carlo technique for computing Bayesian estimates of the distribution parameters.

William Rodi; Craig A. Schultz; Gardar Johannesson; Stephen C. Myers

2005-05-13

415

[The topological method of analysis of ground contamination of former nuclear test sites].  

PubMed

The method of topological description of former nuclear tests in demonstrated in this paper. The information about the field is extracted from the topology of 2D crossections of 3D surfaces constructed on experimental data. The complexity of izolines' system for each cross section in estimated by algebraic sum of contours bounded the areas where the field is higher then the given level. That gives a possibility to do morphological analysis of radionuclide fields using archive data and can be used for ecological diagnosis of different contaminations. The using of this method is shown on some examples. PMID:10576021

Makarenko, N G; Karimova, L M; Beliashov, D N; Komarov, I I; Aristova, I L; Kardashev, A V; Iushkov, A V

1999-01-01

416

A generic risk-based surveying method for invading plant pathogens.  

PubMed

Invasive plant pathogens are increasing with international trade and travel, with damaging environmental and economic consequences. Recent examples include tree diseases such as sudden oak death in the Western United States and ash dieback in Europe. To control an invading pathogen it is crucial that newly infected sites are quickly detected so that measures can be implemented to control the epidemic. However, since sampling resources are often limited, not all locations can be inspected and locations must be prioritized for surveying. Existing approaches to achieve this are often species specific and rely on detailed data collection and parameterization, which is difficult, especially when new arrivals are unanticipated. Consequently regulatory sampling responses are often ad hoc and developed without due consideration of epidemiology, leading to the suboptimal deployment of expensive sampling resources. We introduce a flexible risk-based sampling method that is pathogen generic and enables available information to be utilized to develop epidemiologically informed sampling programs for virtually any biologically relevant plant pathogen. By targeting risk we aim to inform sampling schemes that identify high-impact locations that can be subsequently treated in order to reduce inoculum in the landscape. This "damage limitation" is often the initial management objective following the first discovery of a new invader. Risk at each location is determined by the product of the basic reproductive number (R0), as a measure of local epidemic size, and the probability of infection. We illustrate how the risk estimates can be used to prioritize a survey by weighting a random sample so that the highest-risk locations have the highest probability of selection. We demonstrate and test the method using a high-quality spatially and temporally resolved data set on Huanglongbing disease (HLB) in Florida, USA. We show that even when available epidemiological information is relatively minimal, the method has strong predictive value and can result in highly effective targeted surveying plans. PMID:24988776

Parnell, S; Gottwald, T R; Riley, T; van den Bosch, F

2014-06-01

417

Mathematical Methods Applied to the Survey of Uranium Deposits; APPLICATION DES METHODES MATHEMATIQUES A L'ETUDE DES GISEMENTS D'URANIUM  

Microsoft Academic Search

The application of statistical methods to a survey of uranium deposits ; in France was studied. The gamma emission of uranium and its connection with ; grade was used as the standard in the survey from the first explorations to ; chemical processing. The correlation between radioactivity and uranium content ; was studied and it was shown that it is

P. Formery; V. Ziegler

1959-01-01

418

Survey of in-situ and remote sensing methods for soil moisture determination  

NASA Technical Reports Server (NTRS)

General methods for determining the moisture content in the surface layers of the soil based on in situ or point measurements, soil water models and remote sensing observations are surveyed. In situ methods described include gravimetric techniques, nuclear techniques based on neutron scattering or gamma-ray attenuation, electromagnetic techniques, tensiometric techniques and hygrometric techniques. Soil water models based on column mass balance treat soil moisture contents as a result of meteorological inputs (precipitation, runoff, subsurface flow) and demands (evaporation, transpiration, percolation). The remote sensing approaches are based on measurements of the diurnal range of surface temperature and the crop canopy temperature in the thermal infrared, measurements of the radar backscattering coefficient in the microwave region, and measurements of microwave emission or brightness temperature. Advantages and disadvantages of the various methods are pointed out, and it is concluded that a successful monitoring system must incorporate all of the approaches considered.

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

1981-01-01

419

Application of the two-microphone method for in-situ ground impedance measurements  

E-print Network

Oldenburg University, Inst. of Physics, 26111 Oldenburg, Germany Abstract The two-microphone method covered soccer field of standard size. Dry condition. #12;3. A flat sand covered area used for long jump of the soccer field. Slightly wet as it had rained the day before. The weather was sunny with temperature

Vormann, Matthias

420

GROUND-WATER QUALITY CLASSIFICATION FOR THE VALLEY-FILL AQUIFER IN SPANISH VALLEY, GRAND AND SAN JUAN COUNTIES, UTAH --A BASIS FOR PRESERVING HIGH QUALITY GROUND-WATER RESOURCES, UTAH GEOLOGICAL SURVEY  

EPA Science Inventory

The proposed study will consist of an evaluation of current ground-water quality using the Utah Water Quality Board's ground-water-quality classification system based mostly on total-dissolved-solids concentrations as follows: class 1A (Pristine), less than 500 mg/L; class 2 (dr...

421

Survey of artificial intelligence methods for detection and identification of component faults in nuclear power plants  

SciTech Connect

A comprehensive survey of computer-based systems that apply artificial intelligence methods to detect and identify component faults in nuclear power plants is presented. Classification criteria are established that categorize artificial intelligence diagnostic systems according to the types of computing approaches used (e.g., computing tools, computer languages, and shell and simulation programs), the types of methodologies employed (e.g., types of knowledge, reasoning and inference mechanisms, and diagnostic approach), and the scope of the system. The major issues of process diagnostics and computer-based diagnostic systems are identified and cross-correlated with the various categories used for classification. Ninety-five publications are reviewed.

Reifman, J. [Argonne National Lab., IL (United States). Reactor Analysis Div.

1997-07-01

422

Survey of the status of finite element methods for partial differential equations  

NASA Technical Reports Server (NTRS)

The finite element methods (FEM) have proved to be a powerful technique for the solution of boundary value problems associated with partial differential equations of either elliptic, parabolic, or hyperbolic type. They also have a good potential for utilization on parallel computers particularly in relation to the concept of domain decomposition. This report is intended as an introduction to the FEM for the nonspecialist. It contains a survey which is totally nonexhaustive, and it also contains as an illustration, a report on some new results concerning two specific applications, namely a free boundary fluid-structure interaction problem and the Euler equations for inviscid flows.

Temam, Roger

1986-01-01

423

Radar Cuts Subsoil Survey Costs  

NASA Technical Reports Server (NTRS)

Soil features located with minimum time and labor. Ground-penetrating radar (GPR) system supplements manual and mechanical methods in performing subsurface soil survey. Mobile system obtains graphic profile of soil discontinuities and interfaces as function of depth. One or two test borings necessary to substantiate soil profile. GPR proves useful as reconnaissance tool.

Johnson, R.; Glaccum, R.

1984-01-01

424

Canada-France Redshift Survey. XI. Morphology of High-Redshift Field Galaxies from High-Resolution Ground-based Imaging  

NASA Astrophysics Data System (ADS)

The 143 galaxies with secure redshifts (z_median_ = 0.62) from the 1415 + 52 field of the Canada-France Redshift Survey have been imaged with median seeing of 0.67" (FWHM). Structural parameters have been derived by fitting multicomponent models and the results confirm two phenomena seen in a smaller sample of galaxies imaged with the Hubble Space Telescope. First, 11 +/- 3% of the galaxies lie off the normal locus of color versus bulge fraction B/T: This class of objects ("blue nucleated galaxies," or BNGs) was identified using HST observations (Schade et al. 1995, hereafter CFRS IX), and it was shown that they are associated with peculiar/asymmetric structure and merger/interactions. The observed frequency of BNGs in this sample is 14 +/- 4% 0.5 < z < 1.2 and 6^+6^_- 3_% at 0.2 < z < 0.5, but the true frequency is likely to be a factor ~2 higher after corrections are made for the effect of asymmetric/peculiar structures. Galaxy disks at 0.5 < z < 1.1 are found to have a mean rest-frame, inclination-corrected central surface brightness of ?_AB_(B) = 19.8 +/- 0.1 mag arcsec^-2^, ~1.6 mag brighter than the Freeman (1970) value. At low redshift (0.2 < z < 0.5) the mean surface brightness [?_AB_(B) = 21.3 +/- 0.25] is consistent with the Freeman value. These results are consistent with the HST observations. With larger numbers of galaxies and therefore more statistical weight they demonstrate the capabilities, and limits, of ground-based work in the study of galaxy morphology at high redshift.

Schade, David; Lilly, S. J.; Le Fevre, O.; Hammer, F.; Crampton, D.

1996-06-01

425

Geochemical orientation survey of stream sediment, stream water, and ground water near uranium prospects, Monticello area, New York. National Uranium Resource Evaluation Program  

SciTech Connect

A detailed geochemical test survey has been conducted in a 570 sq km area around six small copper-uranium prospects in sandstones of the Devonian Catskill Formation near Monticello in southern New York state. This report summarizes and interprets the data for about 500 stream sediment samples, 500 stream water samples, and 500 ground water samples, each analyzed for 40 to 50 elements. The groundwater samples furnish distinctive anomalies for uranium, helium, radon, and copper near the mineralized localities, but the samples must be segregated into aquifers in order to obtain continuous well-defined anomalies. Two zones of uranium-rich water (1 to 16 parts per billion) can be recognized on cross sections; the upper zone extends through the known occurrences. The anomalies in uranium and helium are strongest in the deeper parts of the aquifers and are diluted in samples from shallow wells. In stream water, copper and uranium are slightly anomalous, as in an ore factor derived from factor analysis. Ratios of copper, uranium, and zinc to conductivity improve the resolution of anomalies. In stream sediment, extractable uranium, copper, niobium, vanadium, and an ore factor furnish weak anomalies, and ratios of uranium and copper to zinc improve the definition of anomalies. The uranium/thorium ratio is not helpful. Published analyses of rock samples from the nearby stratigraphic section show distinct anomalies in the zone containing the copper-uranium occurrences. This report is being issued without the normal detailed technical and copy editing, to make the data available to the public before the end of the National Uranium Reconnaissance Evaluation program.

Rose, A. W.; Smith, A. T.; Wesolowski, D.

1982-08-01

426

Analytical methods of the U.S. Geological Survey's New York District Water-Analysis Laboratory  

USGS Publications Warehouse

The New York District of the U.S. Geological Survey (USGS) in Troy, N.Y., operates a water-analysis laboratory for USGS watershed-research projects in the Northeast that require analyses of precipitation and of dilute surface water and soil water for major ions; it also provides analyses of certain chemical constituents in soils and soil gas samples. This report presents the methods for chemical analyses of water samples, soil-water samples, and soil-gas samples collected in wateshed-research projects. The introduction describes the general materials and technicques for eachmethod and explains the USGS quality-assurance program and data-management procedures; it also explains the use of cross reference to the three most commonly used methods manuals for analysis of dilute waters. The body of the report describes the analytical procedures for (1) solution analysis, (2) soil analysis, and (3) soil-gas analysis. The methods are presented in alphabetical order by constituent. The method for each constituent is preceded by (1) reference codes for pertinent sections of the three manuals mentioned above, (2) a list of the method's applications, and (3) a summary of the procedure. The methods section for each constitutent contains the following categories: instrumentation and equipment, sample preservation and storage, reagents and standards, analytical procedures, quality control, maintenance, interferences, safety considerations, and references. Sufficient information is presented for each method to allow the resulting data to be appropriately used in environmental samples.

Lawrence, Gregory B.; Lincoln, Tricia A.; Horan-Ross, Debra A.; Olson, Mark L.; Waldron, Laura A.

1995-01-01

427

Effects of cooking methods and chemical tenderizers on survival of Escherichia coli O157:H7 in ground beef patties.  

PubMed

This study evaluated chemical tenderizers and cooking methods to inactivate Escherichia coli O157:H7 in ground beef patties (model system for non-intact beef). Ground beef was inoculated with E. coli O157:H7 and mixed with (i) nothing (control), (ii) calcium chloride (CC) and flavoring agents (FA), (iii) CC, FA, and acetic acid (AA), (iv) sodium chloride (SC), sodium tripolyphosphate (ST), and potassium lactate (PL), and (v) the combination of SC, ST, PL, and AA. Patties were stored in aerobic or vacuum bags at -20, 4, and 12°C. Samples were grilled, broiled, or pan-fried to 60 or 65°C. Total bacterial and E. coli O157:H7 populations remained unchanged during storage. Broiling was more effective in reducing E. coli O157:H7 than grilling and pan-frying, and acidified tenderizers reduced E. coli O157:H7 more than non-acidified tenderizers in broiling. Higher reductions were observed at 65°C than 60°C in broiled and grilled samples. These results indicate that acidified tenderizers and broiling may be useful in non-intact beef safety. PMID:23747624

Yoon, Yohan; Geornaras, Ifigenia; Mukherjee, Avik; Belk, Keith E; Scanga, John A; Smith, Gary C; Sofos, John N

2013-10-01

428

Projection gradient method for energy functional minimization with a constraint and its application to computing the ground state of spin-orbit-coupled Bose-Einstein condensates  

NASA Astrophysics Data System (ADS)

In this study, we propose a projection gradient method for energy functional minimization with a constraint, which we use to compute the ground state of spin-orbit-coupled Bose-Einstein condensates at extremely low temperatures. The method has the advantage that it maintains the constraint when evolving a gradient flow to find the energy functional minimization under a constraint. The original gradient projection method for energy functional minimization under a constraint only considers an energy functional with real functions as variables. Thus, we extend it to consider complex functions as independent variables. We apply the newly proposed method to study the ground state solution of spin-orbit-coupled pseudo-spin 1/2 Bose-Einstein condensates. Detailed numerical results demonstrate the effectiveness of our method. Using this method, we found various types of ground state structures of spin-orbit coupled Bose-Einstein condensates.

Wang, Hanquan; Xu, Zhiguo

2014-11-01

429

Supplementary Methods for "A worldwide survey of haplotype vari-ation and linkage disequilibrium in the human genome"  

E-print Network

Supplementary Methods for "A worldwide survey of haplotype vari- ation and linkage disequilibrium a representative view of worldwide patterns of long- and short-range linkage disequilibrium (LD) across the human

Rosenberg, Noah

430

Comparing the cloud vertical structure derived from several methods based on radiosonde profiles and ground-based remote sensing measurements  

NASA Astrophysics Data System (ADS)

The cloud vertical distribution and especially the cloud base height, which is linked to cloud type, are important characteristics in order to describe the impact of clouds on climate. In this work, several methods for estimating the cloud vertical structure (CVS) based on atmospheric sounding profiles are compared, considering the number and position of cloud layers, with a ground-based system that is taken as a reference: the Active Remote Sensing of Clouds (ARSCL). All methods establish some conditions on the relative humidity, and differ in the use of other variables, the thresholds applied, or the vertical resolution of the profile. In this study, these methods are applied to 193 radiosonde profiles acquired at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site during all seasons o