Science.gov

Sample records for 3-d ground water

  1. Modeling 3-D Slope Stability of Coastal Bluffs Using 3-D Ground-Water Flow, Southwestern Seattle, Washington

    USGS Publications Warehouse

    Brien, Dianne L.; Reid, Mark E.

    2007-01-01

    Landslides are a common problem on coastal bluffs throughout the world. Along the coastal bluffs of the Puget Sound in Seattle, Washington, landslides range from small, shallow failures to large, deep-seated landslides. Landslides of all types can pose hazards to human lives and property, but deep-seated landslides are of significant concern because their large areal extent can cause extensive property damage. Although many geomorphic processes shape the coastal bluffs of Seattle, we focus on large (greater than 3,000 m3), deepseated, rotational landslides that occur on the steep bluffs along Puget Sound. Many of these larger failures occur in advance outwash deposits of the Vashon Drift (Qva); some failures extend into the underlying Lawton Clay Member of the Vashon Drift (Qvlc). The slope stability of coastal bluffs is controlled by the interplay of three-dimensional (3-D) variations in gravitational stress, strength, and pore-water pressure. We assess 3-D slope-stability using SCOOPS (Reid and others, 2000), a computer program that allows us to search a high-resolution digital-elevation model (DEM) to quantify the relative stability of all parts of the landscape by computing the stability and volume of thousands of potential spherical failures. SCOOPS incorporates topography, 3-D strength variations, and 3-D pore pressures. Initially, we use our 3-D analysis methods to examine the effects of topography and geology by using heterogeneous material properties, as defined by stratigraphy, without pore pressures. In this scenario, the least-stable areas are located on the steepest slopes, commonly in Qva or Qvlc. However, these locations do not agree well with observations of deep-seated landslides. Historically, both shallow colluvial landslides and deep-seated landslides have been observed near the contact between Qva and Qvlc, and commonly occur in Qva. The low hydraulic conductivity of Qvlc impedes ground-water flow, resulting in elevated pore pressures at the

  2. Modeling surface and ground water mixing in the hyporheic zone using MODFLOW and MT3D

    NASA Astrophysics Data System (ADS)

    Lautz, Laura K.; Siegel, Donald I.

    2006-11-01

    We used a three-dimensional MODFLOW model, paired with MT3D, to simulate hyporheic zones around debris dams and meanders along a semi-arid stream. MT3D simulates both advective transport and sink/source mixing of solutes, in contrast to particle tracking (e.g. MODPATH), which only considers advection. We delineated the hydrochemically active hyporheic zone based on a new definition, specifically as near-stream subsurface zones receiving a minimum of 10% surface water within a 10-day travel time. Modeling results indicate that movement of surface water into the hyporheic zone is predominantly an advective process. We show that debris dams are a key driver of surface water into the subsurface along the experimental reach, causing the largest flux rates of water across the streambed and creating hyporheic zones with up to twice the cross-sectional area of other hyporheic zones. Hyporheic exchange was also found in highly sinuous segments of the experimental reach, but flux rates are lower and the cross-sectional areas of these zones are generally smaller. Our modeling approach simulated surface and ground water mixing in the hyporheic zone, and thus provides numerical approximations that are more comparable to field-based observations of surface-groundwater exchange than standard particle-tracking simulations.

  3. Age, double porosity, and simple reaction modifications for the MOC3D ground-water transport model

    USGS Publications Warehouse

    Goode, Daniel J.

    1999-01-01

    This report documents modifications for the MOC3D ground-water transport model to simulate (a) ground-water age transport; (b) double-porosity exchange; and (c) simple but flexible retardation, decay, and zero-order growth reactions. These modifications are incorporated in MOC3D version 3.0. MOC3D simulates the transport of a single solute using the method-ofcharacteristics numerical procedure. The age of ground water, that is the time since recharge to the saturated zone, can be simulated using the transport model with an additional source term of unit strength, corresponding to the rate of aging. The output concentrations of the model are in this case the ages at all locations in the model. Double porosity generally refers to a separate immobilewater phase within the aquifer that does not contribute to ground-water flow but can affect solute transport through diffusive exchange. The solute mass exchange rate between the flowing water in the aquifer and the immobile-water phase is the product of the concentration difference between the two phases and a linear exchange coefficient. Conceptually, double porosity can approximate the effects of dead-end pores in a granular porous media, or matrix diffusion in a fractured-rock aquifer. Options are provided for decay and zero-order growth reactions within the immobilewater phase. The simple reaction terms here extend the original model, which included decay and retardation. With these extensions, (a) the retardation factor can vary spatially within each model layer, (b) the decay rate coefficient can vary spatially within each model layer and can be different for the dissolved and sorbed phases, and (c) a zero-order growth reaction is added that can vary spatially and can be different in the dissolved and sorbed phases. The decay and growth reaction terms also can change in time to account for changing geochemical conditions during transport. The report includes a description of the theoretical basis of the model, a

  4. DCM3D: A dual-continuum, three-dimensional, ground-water flow code for unsaturated, fractured, porous media

    SciTech Connect

    Updegraff, C.D. ); Lee, C.E. ); Gallegos, D.P. )

    1991-02-01

    This report constitutes the user's manual for DCM3D. DCM3D is a computer code for solving three-dimensional, ground-water flow problems in variably saturated, fractured porous media. The code is based on a dual-continuum model with porous media comprising one continuum and fractures comprising the other. The continua are connected by a transfer term that depends on the unsaturated permeability of the porous medium. An integrated finite-difference scheme is used to discretize the governing equations in space. The time-dependent term is allowed to remain continuous. The resulting set of ordinary differential equations (ODE's) is solved with a general ODE solver, LSODES. The code is capable of handling transient, spatially dependent source terms and boundary conditions. The boundary conditions can either prescribed head or prescribed flux. 24 refs., 22 figs., 5 tabs.

  5. Advances in 3D soil mapping and water content estimation using multi-channel ground-penetrating radar

    NASA Astrophysics Data System (ADS)

    Moysey, S. M.

    2011-12-01

    Multi-channel ground-penetrating radar systems have recently become widely available, thereby opening new possibilities for shallow imaging of the subsurface. One advantage of these systems is that they can significantly reduce survey times by simultaneously collecting multiple lines of GPR reflection data. As a result, it is becoming more practical to complete 3D surveys - particularly in situations where the subsurface undergoes rapid changes, e.g., when monitoring infiltration and redistribution of water in soils. While 3D and 4D surveys can provide a degree of clarity that significantly improves interpretation of the subsurface, an even more powerful feature of the new multi-channel systems for hydrologists is their ability to collect data using multiple antenna offsets. Central mid-point (CMP) surveys have been widely used to estimate radar wave velocities, which can be related to water contents, by sequentially increasing the distance, i.e., offset, between the source and receiver antennas. This process is highly labor intensive using single-channel systems and therefore such surveys are often only performed at a few locations at any given site. In contrast, with multi-channel GPR systems it is possible to physically arrange an array of antennas at different offsets, such that a CMP-style survey is performed at every point along a radar transect. It is then possible to process this data to obtain detailed maps of wave velocity with a horizontal resolution on the order of centimeters. In this talk I review concepts underlying multi-channel GPR imaging with an emphasis on multi-offset profiling for water content estimation. Numerical simulations are used to provide examples that illustrate situations where multi-offset GPR profiling is likely to be successful, with an emphasis on considering how issues like noise, soil heterogeneity, vertical variations in water content and weak reflection returns affect algorithms for automated analysis of the data. Overall

  6. Berries on the Ground 2 3-D

    NASA Image and Video Library

    2004-02-12

    This 3-D anaglyph, from NASA Mars Exploration Rover Spirit, shows a microscopic image taken of soil featuring round, blueberry-shaped rock formations on the crater floor at Meridiani Planum, Mars. 3D glasses are necessary to view this image.

  7. SUTRA: A model for 2D or 3D saturated-unsaturated, variable-density ground-water flow with solute or energy transport

    USGS Publications Warehouse

    Voss, Clifford I.; Provost, A.M.

    2002-01-01

    SUTRA (Saturated-Unsaturated Transport) is a computer program that simulates fluid movement and the transport of either energy or dissolved substances in a subsurface environment. This upgraded version of SUTRA adds the capability for three-dimensional simulation to the former code (Voss, 1984), which allowed only two-dimensional simulation. The code employs a two- or three-dimensional finite-element and finite-difference method to approximate the governing equations that describe the two interdependent processes that are simulated: 1) fluid density-dependent saturated or unsaturated ground-water flow; and 2) either (a) transport of a solute in the ground water, in which the solute may be subject to: equilibrium adsorption on the porous matrix, and both first-order and zero-order production or decay; or (b) transport of thermal energy in the ground water and solid matrix of the aquifer. SUTRA may also be used to simulate simpler subsets of the above processes. A flow-direction-dependent dispersion process for anisotropic media is also provided by the code and is introduced in this report. As the primary calculated result, SUTRA provides fluid pressures and either solute concentrations or temperatures, as they vary with time, everywhere in the simulated subsurface system. SUTRA flow simulation may be employed for two-dimensional (2D) areal, cross sectional and three-dimensional (3D) modeling of saturated ground-water flow systems, and for cross sectional and 3D modeling of unsaturated zone flow. Solute-transport simulation using SUTRA may be employed to model natural or man-induced chemical-species transport including processes of solute sorption, production, and decay. For example, it may be applied to analyze ground-water contaminant transport problems and aquifer restoration designs. In addition, solute-transport simulation with SUTRA may be used for modeling of variable-density leachate movement, and for cross sectional modeling of saltwater intrusion in

  8. 'Berries' on the Ground 2 (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is the 3-D anaglyph showing a microscopic image taken of soil featuring round, blueberry-shaped rock formations on the crater floor at Meridiani Planum, Mars. This image was taken on the 13th day of the Mars Exploration Rover Opportunity's journey, before the Moessbauer spectrometer, an instrument located on the rover's instrument deployment device, or 'arm,' was pressed down to take measurements. The area in this image is approximately 3 centimeters (1.2 inches) across.

  9. 'Berries' on the Ground 2 (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is the 3-D anaglyph showing a microscopic image taken of soil featuring round, blueberry-shaped rock formations on the crater floor at Meridiani Planum, Mars. This image was taken on the 13th day of the Mars Exploration Rover Opportunity's journey, before the Moessbauer spectrometer, an instrument located on the rover's instrument deployment device, or 'arm,' was pressed down to take measurements. The area in this image is approximately 3 centimeters (1.2 inches) across.

  10. 'Berries' on the Ground 2 (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is the 3-D anaglyph showing a microscopic image taken of soil featuring round, blueberry-shaped rock formations on the crater floor at Meridiani Planum, Mars. This image was taken on the 13th day of the Mars Exploration Rover Opportunity's journey, after the Moessbauer spectrometer, an instrument located on the rover's instrument deployment device, or 'arm,' was pressed down to measure the soil's iron mineralogy. Note the donut-shaped imprint of the instrument in the lower part of the image. The area in this image is approximately 3 centimeters (1.2 inches) across.

  11. Documentation of a computer program to simulate lake-aquifer interaction using the MODFLOW ground water flow model and the MOC3D solute-transport model

    USGS Publications Warehouse

    Merritt, Michael L.; Konikow, Leonard F.

    2000-01-01

    Heads and flow patterns in surficial aquifers can be strongly influenced by the presence of stationary surface-water bodies (lakes) that are in direct contact, vertically and laterally, with the aquifer. Conversely, lake stages can be significantly affected by the volume of water that seeps through the lakebed that separates the lake from the aquifer. For these reasons, a set of computer subroutines called the Lake Package (LAK3) was developed to represent lake/aquifer interaction in numerical simulations using the U.S. Geological Survey three-dimensional, finite-difference, modular ground-water flow model MODFLOW and the U.S. Geological Survey three-dimensional method-of-characteristics solute-transport model MOC3D. In the Lake Package described in this report, a lake is represented as a volume of space within the model grid which consists of inactive cells extending downward from the upper surface of the grid. Active model grid cells bordering this space, representing the adjacent aquifer, exchange water with the lake at a rate determined by the relative heads and by conductances that are based on grid cell dimensions, hydraulic conductivities of the aquifer material, and user-specified leakance distributions that represent the resistance to flow through the material of the lakebed. Parts of the lake may become ?dry? as upper layers of the model are dewatered, with a concomitant reduction in lake surface area, and may subsequently rewet when aquifer heads rise. An empirical approximation has been encoded to simulate the rewetting of a lake that becomes completely dry. The variations of lake stages are determined by independent water budgets computed for each lake in the model grid. This lake budget process makes the package a simulator of the response of lake stage to hydraulic stresses applied to the aquifer. Implementation of a lake water budget requires input of parameters including those representing the rate of lake atmospheric recharge and evaporation

  12. Ground Motion and Variability from 3-D Deterministic Broadband Simulations

    NASA Astrophysics Data System (ADS)

    Withers, Kyle Brett

    The accuracy of earthquake source descriptions is a major limitation in high-frequency (> 1 Hz) deterministic ground motion prediction, which is critical for performance-based design by building engineers. With the recent addition of realistic fault topography in 3D simulations of earthquake source models, ground motion can be deterministically calculated more realistically up to higher frequencies. We first introduce a technique to model frequency-dependent attenuation and compare its impact on strong ground motions recorded for the 2008 Chino Hills earthquake. Then, we model dynamic rupture propagation for both a generic strike-slip event and blind thrust scenario earthquakes matching the fault geometry of the 1994 Mw 6.7 Northridge earthquake along rough faults up to 8 Hz. We incorporate frequency-dependent attenuation via a power law above a reference frequency in the form Q0fn, with high accuracy down to Q values of 15, and include nonlinear effects via Drucker-Prager plasticity. We model the region surrounding the fault with and without small-scale medium complexity in both a 1D layered model characteristic of southern California rock and a 3D medium extracted from the SCEC CVMSi.426 including a near-surface geotechnical layer. We find that the spectral acceleration from our models are within 1-2 interevent standard deviations from recent ground motion prediction equations (GMPEs) and compare well with that of recordings from strong ground motion stations at both short and long periods. At periods shorter than 1 second, Q(f) is needed to match the decay of spectral acceleration seen in the GMPEs as a function of distance from the fault. We find that the similarity between the intraevent variability of our simulations and observations increases when small-scale heterogeneity and plasticity are included, extremely important as uncertainty in ground motion estimates dominates the overall uncertainty in seismic risk. In addition to GMPEs, we compare with simple

  13. Complex Resistivity 3D Imaging for Ground Reinforcement Site

    NASA Astrophysics Data System (ADS)

    Son, J.; Kim, J.; Park, S.

    2012-12-01

    Induced polarization (IP) method is used for mineral exploration and generally classified into two categories, time and frequency domain method. IP method in frequency domain measures amplitude and absolute phase to the transmitted currents, and is often called spectral induced polarization (SIP) when measurement is made for the wide-band frequencies. Our research group has been studying the modeling and inversion algorithms of complex resistivity method since several years ago and recently started to apply this method for various field applications. We already completed the development of 2/3D modeling and inversion program and developing another algorithm to use wide-band data altogether. Until now complex resistivity (CR) method was mainly used for the surface or tomographic survey of mineral exploration. Through the experience, we can find that the resistivity section from CR method is very similar with that of conventional resistivity method. Interpretation of the phase section is generally well matched with the geological information of survey area. But because most of survey area has very touch and complex terrain, 2D survey and interpretation are used generally. In this study, the case study of 3D CR survey conducted for the site where ground reinforcement was done to prevent the subsidence will be introduced. Data was acquired with the Zeta system, the complex resistivity measurement system produced by Zonge Co. using 8 frequencies from 0.125 to 16 Hz. 2D survey was conducted for total 6 lines with 5 m dipole spacing and 20 electrodes. Line length is 95 meter for every line. Among these 8 frequency data, data below 1 Hz was used considering its quality. With the 6 line data, 3D inversion was conducted. Firstly 2D interpretation was made with acquired data and its results were compared with those of resistivity survey. Resulting resistivity image sections of CR and resistivity method were very similar. Anomalies in phase image section showed good agreement

  14. Ground Water

    USGS Publications Warehouse

    ,

    1986-01-01

    Some water underlies the Earth's surface almost everywhere, beneath hills, mountains,plains, and deserts. It's not always accessible, or fresh enough for use without treatment, and it's sometimes difficult to locate or to measure and descri be. This water may occur close to the land surface, as in a marsh, or it may lie many hundreds of feet below the surface, as in some arid areas of the West. Water at very shallow depths might be just a few hours old ; at moderate depth, it may be 100 years old; and at great depth or after having flowed long distances from places of entry, water may be several thousands of years old . Water under the Earth's surface is called ground water.

  15. HST3D; a computer code for simulation of heat and solute transport in three-dimensional ground-water flow systems

    USGS Publications Warehouse

    Kipp, K.L.

    1987-01-01

    The Heat- and Soil-Transport Program (HST3D) simulates groundwater flow and associated heat and solute transport in three dimensions. The three governing equations are coupled through the interstitial pore velocity, the dependence of the fluid density on pressure, temperature, the solute-mass fraction , and the dependence of the fluid viscosity on temperature and solute-mass fraction. The solute transport equation is for only a single, solute species with possible linear equilibrium sorption and linear decay. Finite difference techniques are used to discretize the governing equations using a point-distributed grid. The flow-, heat- and solute-transport equations are solved , in turn, after a particle Gauss-reduction scheme is used to modify them. The modified equations are more tightly coupled and have better stability for the numerical solutions. The basic source-sink term represents wells. A complex well flow model may be used to simulate specified flow rate and pressure conditions at the land surface or within the aquifer, with or without pressure and flow rate constraints. Boundary condition types offered include specified value, specified flux, leakage, heat conduction, and approximate free surface, and two types of aquifer influence functions. All boundary conditions can be functions of time. Two techniques are available for solution of the finite difference matrix equations. One technique is a direct-elimination solver, using equations reordered by alternating diagonal planes. The other technique is an iterative solver, using two-line successive over-relaxation. A restart option is available for storing intermediate results and restarting the simulation at an intermediate time with modified boundary conditions. This feature also can be used as protection against computer system failure. Data input and output may be in metric (SI) units or inch-pound units. Output may include tables of dependent variables and parameters, zoned-contour maps, and plots of the

  16. Object Segmentation and Ground Truth in 3D Embryonic Imaging

    PubMed Central

    Rajasekaran, Bhavna; Uriu, Koichiro; Valentin, Guillaume; Tinevez, Jean-Yves; Oates, Andrew C.

    2016-01-01

    Many questions in developmental biology depend on measuring the position and movement of individual cells within developing embryos. Yet, tools that provide this data are often challenged by high cell density and their accuracy is difficult to measure. Here, we present a three-step procedure to address this problem. Step one is a novel segmentation algorithm based on image derivatives that, in combination with selective post-processing, reliably and automatically segments cell nuclei from images of densely packed tissue. Step two is a quantitative validation using synthetic images to ascertain the efficiency of the algorithm with respect to signal-to-noise ratio and object density. Finally, we propose an original method to generate reliable and experimentally faithful ground truth datasets: Sparse-dense dual-labeled embryo chimeras are used to unambiguously measure segmentation errors within experimental data. Together, the three steps outlined here establish a robust, iterative procedure to fine-tune image analysis algorithms and microscopy settings associated with embryonic 3D image data sets. PMID:27332860

  17. Object Segmentation and Ground Truth in 3D Embryonic Imaging.

    PubMed

    Rajasekaran, Bhavna; Uriu, Koichiro; Valentin, Guillaume; Tinevez, Jean-Yves; Oates, Andrew C

    2016-01-01

    Many questions in developmental biology depend on measuring the position and movement of individual cells within developing embryos. Yet, tools that provide this data are often challenged by high cell density and their accuracy is difficult to measure. Here, we present a three-step procedure to address this problem. Step one is a novel segmentation algorithm based on image derivatives that, in combination with selective post-processing, reliably and automatically segments cell nuclei from images of densely packed tissue. Step two is a quantitative validation using synthetic images to ascertain the efficiency of the algorithm with respect to signal-to-noise ratio and object density. Finally, we propose an original method to generate reliable and experimentally faithful ground truth datasets: Sparse-dense dual-labeled embryo chimeras are used to unambiguously measure segmentation errors within experimental data. Together, the three steps outlined here establish a robust, iterative procedure to fine-tune image analysis algorithms and microscopy settings associated with embryonic 3D image data sets.

  18. Ground water contamination

    SciTech Connect

    Not Available

    1991-01-01

    This book covers: Ground water contamination and basic concepts of water law; Federal law governing water contamination and remediation; Ground water flow and contaminant migration; Ground water cleanup under CERCLA; Technical methods of remediation and prevention of contamination; Liability for ground water contamination; State constraints on contamination of ground water; Water quantity versus water quality; Prevention of use of contaminated ground water as an alternative to remediation; Economic considerations in liability for ground water contamination; and Contamination, extraction, and injection issues.

  19. 3D flexible water channel: stretchability of nanoscale water bridge

    NASA Astrophysics Data System (ADS)

    Chen, Jige; Wang, Chunlei; Wei, Ning; Wan, Rongzheng; Gao, Yi

    2016-03-01

    Artificial water channels can contribute to a better understanding of natural water channels and offer a highly selective, advanced conductance system. Most studies use nanotubes, however it is difficult to fabricate a flexible structure, and the nanosized diameter brings nanoconfinement effects, and nanotube toxicity arouses biosafety concerns. In this paper, we use an electric field to restrain the water molecules to form a nanoscale water bridge as an artificial water channel to connect a separated solid plate by molecular dynamics simulations. We observe strong 3D flexible stretchability in the water bridge, maintaining a variable length and an arbitrary angle for a considerably long time. The stretching of the water bridge enables it to be polarized at an arbitrary angle and the stretchability is linearly dependent upon the polarization strength. More interestingly, we show the possibility of establishing complex water networks, e.g., triangle, rectangle, hexagon, and tetrahedron-tetrahedron water networks. Our results may help realize structurally flexible and environmentally friendly water channels for lab-on-a-chip applications in nanofluidics.Artificial water channels can contribute to a better understanding of natural water channels and offer a highly selective, advanced conductance system. Most studies use nanotubes, however it is difficult to fabricate a flexible structure, and the nanosized diameter brings nanoconfinement effects, and nanotube toxicity arouses biosafety concerns. In this paper, we use an electric field to restrain the water molecules to form a nanoscale water bridge as an artificial water channel to connect a separated solid plate by molecular dynamics simulations. We observe strong 3D flexible stretchability in the water bridge, maintaining a variable length and an arbitrary angle for a considerably long time. The stretching of the water bridge enables it to be polarized at an arbitrary angle and the stretchability is linearly

  20. Effect of rapid grounding line migration investigated with 3D ice sheet-ice shelf models (MISMIP3d)

    NASA Astrophysics Data System (ADS)

    Pattyn, F.; Docquier, D.; Durand, G.; Favier, L.; Gagliardini, O.; Hindmarsh, R.; Zwinger, T.; Mismip3d Participants

    2012-04-01

    Understanding and attributing future sea-level changes demands serious efforts on the development of efficient ice sheet-ice shelf models that capture the essential physics and mechanics of grounding line behavior. While semi-analytical solutions for grounding line behavior are available for the flowline case, such solution fails to exist for more complex three-dimensional geometries. A way of evaluating the quality of ice sheet models is to verify them against more complex model solutions under controlled conditions (Marine Ice Sheet Model Intercomparison - MISMIP). Given the computational demands of such models, it is extremely attractive from a computational point of view to use flux/thickness parameterizations in 3d models. Here we investigated the transition between ice sheet and ice shelf with series of different numerical models, ranging from full Stokes (Elmer/Ice) models, pseudo-spectral methods to a 2d vertically integrated finite-difference 'shelfy-stream' model, taking into account grounding line dynamics, and using parameterizations by Schoof (2007) and Pollard and DeConto (2009). Rapid grounding line migration was provoked by changing sliding at the grounding line, resulting in curved grounding lines influenced by lateral effects. We tested whether flux parameterizations are still valid under such conditions, especially when buttressing effects are taken into account. Results of other participants in the intercomparison exercise are presented alongside the initial benchmark results.

  1. Ground water

    USGS Publications Warehouse

    ,

    1999-01-01

    Some water underlies the Earth's surface almost everywhere, beneath hills, mountains, plains, and deserts. It is not always accessible, or fresh enough for use without treatment, and it's sometimes difficult to locate or to measure and describe. This water may occur close to the land surface, as in a marsh, or it may lie many hundreds of feet below the surface, as in some arid areas of the West. Water at very shallow depths might be just a few hours old; at moderate depth, it may be 100 years old; and at great depth or after having flowed long distances from places of entry, water may be several thousands of years old.

  2. Rural ground water contamination

    SciTech Connect

    D'Itri, F.M.

    1987-01-01

    The contents of this book are: Remedial Actions; Analysis and Control of Rural Ground Wate; Ground Water Contamination Sources; Research Theory, and Practice; and Regulations Pertaining to Rural Ground Water.

  3. 3D Printing by Multiphase Silicone/Water Capillary Inks.

    PubMed

    Roh, Sangchul; Parekh, Dishit P; Bharti, Bhuvnesh; Stoyanov, Simeon D; Velev, Orlin D

    2017-08-01

    3D printing of polymers is accomplished easily with thermoplastics as the extruded hot melt solidifies rapidly during the printing process. Printing with liquid polymer precursors is more challenging due to their longer curing times. One curable liquid polymer of specific interest is polydimethylsiloxane (PDMS). This study demonstrates a new efficient technique for 3D printing with PDMS by using a capillary suspension ink containing PDMS in the form of both precured microbeads and uncured liquid precursor, dispersed in water as continuous medium. The PDMS microbeads are held together in thixotropic granular paste by capillary attraction induced by the liquid precursor. These capillary suspensions possess high storage moduli and yield stresses that are needed for direct ink writing. They could be 3D printed and cured both in air and under water. The resulting PDMS structures are remarkably elastic, flexible, and extensible. As the ink is made of porous, biocompatible silicone that can be printed directly inside aqueous medium, it can be used in 3D printed biomedical products, or in applications such as direct printing of bioscaffolds on live tissue. This study demonstrates a number of examples using the high softness, elasticity, and resilience of these 3D printed structures. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Ground water and energy

    SciTech Connect

    Not Available

    1980-11-01

    This national workshop on ground water and energy was conceived by the US Department of Energy's Office of Environmental Assessments. Generally, OEA needed to know what data are available on ground water, what information is still needed, and how DOE can best utilize what has already been learned. The workshop focussed on three areas: (1) ground water supply; (2) conflicts and barriers to ground water use; and (3) alternatives or solutions to the various issues relating to ground water. (ACR)

  5. Ground Water Remediation Technologies

    EPA Science Inventory

    The USEPA's Ground Water and Ecosystems Restoration Division (GWERD) conducts research and provides technical assistance to support the development of strategies and technologies to protect and restore ground water, surface water, and ecosystems impacted by man-made and natural...

  6. Time-lapse 3D ground-penetrating radar during plot-scale infiltration experiments

    NASA Astrophysics Data System (ADS)

    Allroggen, Niklas; Jackisch, Conrad; Tronicke, Jens

    2016-04-01

    In electrical resistive soils, surface-based ground-penetrating radar (GPR) is known as the geophysical tool providing the highest spatial resolution. Thus, 2D and 3D GPR surveys are commonly used for imaging subsurface structures or estimating soil moisture content. Due to its sensitivity to soil moisture and its non-invasive character, GPR provides a large potential to monitor soil moisture variation at high temporal and spatial resolution. As shown in previous experiments, the acquisition of time-lapse GPR data under field conditions requires a high data quality in terms of repeatability as well as spatial and temporal resolution. We present hydrogeophysical field experiments at the plot scale (1m x 1m), during which we record time-lapse 3D GPR. For GPR data acquisition, we use a pulseEKKO PRO GPR system equipped with a pair of 500 MHz antennas in combination with a specially designed metal-free measuring platform. Additionally, we collect tracer and soil moisture data, which are used to improve the interpretation of the GPR data with special focus on preferential flow paths and their structured advective flow field. After an accurate time-lapse GPR data processing, we compare 3D reflection events before and after infiltration and quantitatively interpret their relative time-shift in terms of soil moisture variations. Thereby, we are able to account for basically all of the infiltrated water. The first experiments demonstrate the general applicability of our experimental approach but are limited by the number of acquired time steps and measurement during the sprinkling period (the time of the highest temporal dynamics) are not possible at all. Based on this experience we redesign our experimental setup to continuously collect GPR data during irrigation and infiltration. Thereby, we strongly increase the temporal resolution of our measurements, improve the interpretability of the GPR data, and monitor the temporal and spatial dynamics of shallow subsurface

  7. GEO3D - Three-Dimensional Computer Model of a Ground Source Heat Pump System

    SciTech Connect

    James Menart

    2013-06-07

    This file is the setup file for the computer program GEO3D. GEO3D is a computer program written by Jim Menart to simulate vertical wells in conjunction with a heat pump for ground source heat pump (GSHP) systems. This is a very detailed three-dimensional computer model. This program produces detailed heat transfer and temperature field information for a vertical GSHP system.

  8. 3D Printing-Based Integrated Water Quality Sensing System.

    PubMed

    Banna, Muinul; Bera, Kaustav; Sochol, Ryan; Lin, Liwei; Najjaran, Homayoun; Sadiq, Rehan; Hoorfar, Mina

    2017-06-08

    The online and accurate monitoring of drinking water supply networks is critically in demand to rapidly detect the accidental or deliberate contamination of drinking water. At present, miniaturized water quality monitoring sensors developed in the laboratories are usually tested under ambient pressure and steady-state flow conditions; however, in Water Distribution Systems (WDS), both the pressure and the flowrate fluctuate. In this paper, an interface is designed and fabricated using additive manufacturing or 3D printing technology-material extrusion (Trade Name: fused deposition modeling, FDM) and material jetting-to provide a conduit for miniaturized sensors for continuous online water quality monitoring. The interface is designed to meet two main criteria: low pressure at the inlet of the sensors and a low flowrate to minimize the water bled (i.e., leakage), despite varying pressure from WDS. To meet the above criteria, a two-dimensional computational fluid dynamics model was used to optimize the geometry of the channel. The 3D printed interface, with the embedded miniaturized pH and conductivity sensors, was then tested at different temperatures and flowrates. The results show that the response of the pH sensor is independent of the flowrate and temperature. As for the conductivity sensor, the flowrate and temperature affect only the readings at a very low conductivity (4 µS/cm) and high flowrates (30 mL/min), and a very high conductivity (460 µS/cm), respectively.

  9. 3D Printing-Based Integrated Water Quality Sensing System

    PubMed Central

    Banna, Muinul; Bera, Kaustav; Sochol, Ryan; Lin, Liwei; Najjaran, Homayoun; Sadiq, Rehan; Hoorfar, Mina

    2017-01-01

    The online and accurate monitoring of drinking water supply networks is critically in demand to rapidly detect the accidental or deliberate contamination of drinking water. At present, miniaturized water quality monitoring sensors developed in the laboratories are usually tested under ambient pressure and steady-state flow conditions; however, in Water Distribution Systems (WDS), both the pressure and the flowrate fluctuate. In this paper, an interface is designed and fabricated using additive manufacturing or 3D printing technology—material extrusion (Trade Name: fused deposition modeling, FDM) and material jetting—to provide a conduit for miniaturized sensors for continuous online water quality monitoring. The interface is designed to meet two main criteria: low pressure at the inlet of the sensors and a low flowrate to minimize the water bled (i.e., leakage), despite varying pressure from WDS. To meet the above criteria, a two-dimensional computational fluid dynamics model was used to optimize the geometry of the channel. The 3D printed interface, with the embedded miniaturized pH and conductivity sensors, was then tested at different temperatures and flowrates. The results show that the response of the pH sensor is independent of the flowrate and temperature. As for the conductivity sensor, the flowrate and temperature affect only the readings at a very low conductivity (4 µS/cm) and high flowrates (30 mL/min), and a very high conductivity (460 µS/cm), respectively. PMID:28594387

  10. Real-time 3D dose imaging in water phantoms: reconstruction from simultaneous EPID-Cherenkov 3D imaging (EC3D)

    NASA Astrophysics Data System (ADS)

    Bruza, P.; Andreozzi, J. M.; Gladstone, D. J.; Jarvis, L. A.; Rottmann, J.; Pogue, B. W.

    2017-05-01

    Combination of electronic portal imaging device (EPID) transmission imaging with frontal Cherenkov imaging enabled real-time 3D dosimetry of clinical X-ray beams in water phantoms. The EPID provides a 2D transverse distribution of attenuation which can be back-projected to estimate accumulated dose, while the Cherenkov image provides an accurate lateral view of the dose versus depth. Assuming homogeneous density and composition of the phantom, both images can be linearly combined into a true 3D distribution of the deposited dose. We describe the algorithm for volumetric dose reconstruction, and demonstrate the results of a volumetric modulated arc therapy (VMAT) 3D dosimetry.

  11. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  12. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  13. Ground water: a review.

    USGS Publications Warehouse

    Bredehoeft, J.D.

    1983-01-01

    There is growing documentation that a significant portion of the Nation's fresh ground water in the densely populated areas of the USA is contaminated. Because of the slow rates of ground-water movement, ground water once contaminated will remain so for decades, often longer. Cleanup of contaminated ground water is almost always expensive and often technically unfeasible; the expense is often prohibitive. -from Author

  14. Intuitive Terrain Reconstruction Using Height Observation-Based Ground Segmentation and 3D Object Boundary Estimation

    PubMed Central

    Song, Wei; Cho, Kyungeun; Um, Kyhyun; Won, Chee Sun; Sim, Sungdae

    2012-01-01

    Mobile robot operators must make rapid decisions based on information about the robot’s surrounding environment. This means that terrain modeling and photorealistic visualization are required for the remote operation of mobile robots. We have produced a voxel map and textured mesh from the 2D and 3D datasets collected by a robot’s array of sensors, but some upper parts of objects are beyond the sensors’ measurements and these parts are missing in the terrain reconstruction result. This result is an incomplete terrain model. To solve this problem, we present a new ground segmentation method to detect non-ground data in the reconstructed voxel map. Our method uses height histograms to estimate the ground height range, and a Gibbs-Markov random field model to refine the segmentation results. To reconstruct a complete terrain model of the 3D environment, we develop a 3D boundary estimation method for non-ground objects. We apply a boundary detection technique to the 2D image, before estimating and refining the actual height values of the non-ground vertices in the reconstructed textured mesh. Our proposed methods were tested in an outdoor environment in which trees and buildings were not completely sensed. Our results show that the time required for ground segmentation is faster than that for data sensing, which is necessary for a real-time approach. In addition, those parts of objects that were not sensed are accurately recovered to retrieve their real-world appearances. PMID:23235454

  15. Intuitive terrain reconstruction using height observation-based ground segmentation and 3D object boundary estimation.

    PubMed

    Song, Wei; Cho, Kyungeun; Um, Kyhyun; Won, Chee Sun; Sim, Sungdae

    2012-12-12

    Mobile robot operators must make rapid decisions based on information about the robot's surrounding environment. This means that terrain modeling and photorealistic visualization are required for the remote operation of mobile robots. We have produced a voxel map and textured mesh from the 2D and 3D datasets collected by a robot's array of sensors, but some upper parts of objects are beyond the sensors' measurements and these parts are missing in the terrain reconstruction result. This result is an incomplete terrain model. To solve this problem, we present a new ground segmentation method to detect non-ground data in the reconstructed voxel map. Our method uses height histograms to estimate the ground height range, and a Gibbs-Markov random field model to refine the segmentation results. To reconstruct a complete terrain model of the 3D environment, we develop a 3D boundary estimation method for non-ground objects. We apply a boundary detection technique to the 2D image, before estimating and refining the actual height values of the non-ground vertices in the reconstructed textured mesh. Our proposed methods were tested in an outdoor environment in which trees and buildings were not completely sensed. Our results show that the time required for ground segmentation is faster than that for data sensing, which is necessary for a real-time approach. In addition, those parts of objects that were not sensed are accurately recovered to retrieve their real-world appearances.

  16. Water linked 3D coordination polymers: Syntheses, structures and applications

    NASA Astrophysics Data System (ADS)

    Singh, Suryabhan; Bhim, Anupam

    2016-12-01

    Three new coordination polymers (CPs) based on Cd and Pb, [Cd(OBA)(μ-H2O)(H2O)]n1, [Pb(OBA)(μ-H2O)]n2 [where OBA=4,4'-Oxybis(benzoate)] and [Pb(SDBA)(H2O)]n.1/4DMF 3 (SDBA=4,4'-Sulfonyldibenzoate), have been synthesized and characterized. The single crystal structural studies reveal that CPs 1 and 2 have three dimensional structure. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. Compound 3 has a supramolecular 3D structure involving water molecule and hydrogen bonds. A structural transformation is observed when 3 was heated at 100 °C or kept in methanol, forming [Pb(SDBA)]n4. Compound 4 is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4 at room temperature. Luminescence studies revealed that all CPs could be an effective sensor for nitroaromatic explosives.

  17. Large Scale Ice Water Path and 3-D Ice Water Content

    DOE Data Explorer

    Liu, Guosheng

    2008-01-15

    Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the radar/lidar/radiometer observations at the ARM site are single-point measurement, therefore, do not provide horizontal distribution of condensed water. The intention of this product is to provide large-scale distribution of cloud ice water by merging available surface and satellite measurements. The satellite cloud ice water algorithm uses ARM ground-based measurements as baseline, produces datasets for 3-D cloud ice water distributions in a 10 deg x 10 deg area near ARM site. The approach of the study is to expand a (surface) point measurement to an (satellite) areal measurement. That is, this study takes the advantage of the high quality cloud measurements at the point of ARM site. We use the cloud characteristics derived from the point measurement to guide/constrain satellite retrieval, then use the satellite algorithm to derive the cloud ice water distributions within an area, i.e., 10 deg x 10 deg centered at ARM site.

  18. Proceedings of ground water

    SciTech Connect

    Lennon, G.P.

    1991-01-01

    This book contains proceedings of Ground Water. Topics covered include: Practical use and pitfalls of numerical models; Reliability of predictions; Strengths and limitations of coupled flow/transport/geochemical models; Ground water management/water resources; The macrodispersion experiment (made-scale tracer test; Partially saturated models; Use of ground water flow/transport modeling for aquifer evaluation; Aquifer tests and tracer tests; Risk assessment for groundwater pollution control; and Groundwater quality management.

  19. Effects of 3D random correlated velocity perturbations on predicted ground motions

    USGS Publications Warehouse

    Hartzell, S.; Harmsen, S.; Frankel, A.

    2010-01-01

    Three-dimensional, finite-difference simulations of a realistic finite-fault rupture on the southern Hayward fault are used to evaluate the effects of random, correlated velocity perturbations on predicted ground motions. Velocity perturbations are added to a three-dimensional (3D) regional seismic velocity model of the San Francisco Bay Area using a 3D von Karman random medium. Velocity correlation lengths of 5 and 10 km and standard deviations in the velocity of 5% and 10% are considered. The results show that significant deviations in predicted ground velocities are seen in the calculated frequency range (≤1 Hz) for standard deviations in velocity of 5% to 10%. These results have implications for the practical limits on the accuracy of scenario ground-motion calculations and on retrieval of source parameters using higher-frequency, strong-motion data.

  20. Ground Water Modeling Research

    EPA Pesticide Factsheets

    EPA is supporting region, state, and tribal partners at Superfund sites and brownfields to develop new methods to better characterize, monitor, and treat ground water contamination; in order to protect drinking water, surface water, and indoor air.

  1. Robust Locally Weighted Regression For Ground Surface Extraction In Mobile Laser Scanning 3D Data

    NASA Astrophysics Data System (ADS)

    Nurunnabi, A.; West, G.; Belton, D.

    2013-10-01

    A new robust way for ground surface extraction from mobile laser scanning 3D point cloud data is proposed in this paper. Fitting polynomials along 2D/3D points is one of the well-known methods for filtering ground points, but it is evident that unorganized point clouds consist of multiple complex structures by nature so it is not suitable for fitting a parametric global model. The aim of this research is to develop and implement an algorithm to classify ground and non-ground points based on statistically robust locally weighted regression which fits a regression surface (line in 2D) by fitting without any predefined global functional relation among the variables of interest. Afterwards, the z (elevation)-values are robustly down weighted based on the residuals for the fitted points. The new set of down weighted z-values along with x (or y) values are used to get a new fit of the (lower) surface (line). The process of fitting and down-weighting continues until the difference between two consecutive fits is insignificant. Then the final fit represents the ground level of the given point cloud and the ground surface points can be extracted. The performance of the new method has been demonstrated through vehicle based mobile laser scanning 3D point cloud data from urban areas which include different problematic objects such as short walls, large buildings, electric poles, sign posts and cars. The method has potential in areas like building/construction footprint determination, 3D city modelling, corridor mapping and asset management.

  2. 3D Monitoring under the Keciova Mosque (Casbah-Algier, Algeria) with Ground Penetrating Radar Method

    NASA Astrophysics Data System (ADS)

    Kadioglu, Selma; Kagan Kadioglu, Yusuf; Deniz, Kiymet; Akin Akyol, Ali

    2014-05-01

    Keciova (Ketchaoua) Mosque, in Casbah-Algiers, the capital of Algeria, is a UNESCO World Heritage Site. Keciova Mosque was originally built in 1612 by the Ottoman Empire. A RAMAC CU II GPR system and a 250 MHz shielded antenna have been employed inside of the Mosque including the Cathedral and inside of the burial chambers under the Cathedral Site on parallel profiles spaced approximately 0.30 m apart to measure data. After applying standard two-dimensional (2D) and three dimensional (3D) imaging techniques, transparent 3D imaging techniques have been used to photograph the foundational infrastructures, buried remains and safety problems of the Mosque. The results showed that we obtained 3D GPR visualization until 12.0 m in depth. Firstly we imaged the base floor including corridors. Then we monitored buried remains under the first ground level between 5.0-7.0 m in depths. Finally we indicated 3D GPR photographs a spectacular protected buried old mosque structures under the second ground level between 9.0-12.0 m in depths. This project has been supported by Republic of Turkey Prime Ministry Turkish Cooperation and Coordination Agency (TIKA). This study is a contribution to the EU funded COST action TU1208, "Civil Engineering Applications of Ground penetrating Radar".

  3. Ground water in Minnesota

    USGS Publications Warehouse

    Lindholm, Gerald F.; Norvitch, Ralph F.

    1976-01-01

    Although Minnesota is generally rich in ground-water resources, it is not without associated problems. In the western part of the State, ground-water quality is often a problem, especially in deep aquifers. Throughout the State, few buried outwash aquifers have been delineated or evaluated as to their water-yielding capabilities. Some aquifers are highly susceptible to pollution. Planned development and monitoring of water levels and water quality would be beneficial.

  4. Ground Water in Hawaii

    USGS Publications Warehouse

    Gingerich, Stephen B.; Oki, Delwyn S.

    2000-01-01

    Ground water is one of Hawaii's most important natural resources. It is used for drinking water, irrigation, and domestic, commercial, and industrial needs. Ground water provides about 99 percent of Hawaii's domestic water and about 50 percent of all freshwater used in the State. Total ground water pumped in Hawaii was about 500 million gallons per day during 1995, which is less than 3 percent of the average total rainfall (about 21 billion gallons per day) in Hawaii. From this perspective, the ground-water resource appears ample; however, much of the rainfall runs off to the ocean in streams or returns to the atmosphere by evapotranspiration. Furthermore, ground-water resources can be limited because of water-quality, environmental, or economic concerns. Water beneath the ground surface occurs in two principal zones: the unsaturated zone and the saturated zone. In the unsaturated zone, the pore spaces in rocks contain both air and water, whereas in the saturated zone, the pore spaces are filled with water. The upper surface of the saturated zone is referred to as the water table. Water below the water table is referred to as ground water. Ground-water salinity can range from freshwater to that of seawater. Freshwater is commonly considered to be water with a chloride concentration less than 250 mg/L, and this concentration represents about 1.3 percent of the chloride concentration of seawater (19,500 mg/L). Brackish water has a chloride concentration between that of freshwater (250 mg/L) and saltwater (19,500 mg/L).

  5. Ground motion simulations in Marmara (Turkey) region from 3D finite difference method

    NASA Astrophysics Data System (ADS)

    Aochi, Hideo; Ulrich, Thomas; Douglas, John

    2016-04-01

    In the framework of the European project MARSite (2012-2016), one of the main contributions from our research team was to provide ground-motion simulations for the Marmara region from various earthquake source scenarios. We adopted a 3D finite difference code, taking into account the 3D structure around the Sea of Marmara (including the bathymetry) and the sea layer. We simulated two moderate earthquakes (about Mw4.5) and found that the 3D structure improves significantly the waveforms compared to the 1D layer model. Simulations were carried out for different earthquakes (moderate point sources and large finite sources) in order to provide shake maps (Aochi and Ulrich, BSSA, 2015), to study the variability of ground-motion parameters (Douglas & Aochi, BSSA, 2016) as well as to provide synthetic seismograms for the blind inversion tests (Diao et al., GJI, 2016). The results are also planned to be integrated in broadband ground-motion simulations, tsunamis generation and simulations of triggered landslides (in progress by different partners). The simulations are freely shared among the partners via the internet and the visualization of the results is diffused on the project's homepage. All these simulations should be seen as a reference for this region, as they are based on the latest knowledge that obtained during the MARSite project, although their refinement and validation of the model parameters and the simulations are a continuing research task relying on continuing observations. The numerical code used, the models and the simulations are available on demand.

  6. The Martian Water Cycle Based on 3-D Modeling

    NASA Technical Reports Server (NTRS)

    Houben, H.; Haberle, R. M.; Joshi, M. M.

    1999-01-01

    Understanding the distribution of Martian water is a major goal of the Mars Surveyor program. However, until the bulk of the data from the nominal missions of TES, PMIRR, GRS, MVACS, and the DS2 probes are available, we are bound to be in a state where much of our knowledge of the seasonal behavior of water is based on theoretical modeling. We therefore summarize the results of this modeling at the present time. The most complete calculations come from a somewhat simplified treatment of the Martian climate system which is capable of simulating many decades of weather. More elaborate meteorological models are now being applied to study of the problem. The results show a high degree of consistency with observations of aspects of the Martian water cycle made by Viking MAWD, a large number of ground-based measurements of atmospheric column water vapor, studies of Martian frosts, and the widespread occurrence of water ice clouds. Additional information is contained in the original extended abstract.

  7. A Little Knowledge of Ground Motion: Explaining 3-D Physics-Based Modeling to Engineers

    NASA Astrophysics Data System (ADS)

    Porter, K.

    2014-12-01

    Users of earthquake planning scenarios require the ground-motion map to be credible enough to justify costly planning efforts, but not all ground-motion maps are right for all uses. There are two common ways to create a map of ground motion for a hypothetical earthquake. One approach is to map the median shaking estimated by empirical attenuation relationships. The other uses 3-D physics-based modeling, in which one analyzes a mathematical model of the earth's crust near the fault rupture and calculates the generation and propagation of seismic waves from source to ground surface by first principles. The two approaches produce different-looking maps. The more-familiar median maps smooth out variability and correlation. Using them in a planning scenario can lead to a systematic underestimation of damage and loss, and could leave a community underprepared for realistic shaking. The 3-D maps show variability, including some very high values that can disconcert non-scientists. So when the USGS Science Application for Risk Reduction's (SAFRR) Haywired scenario project selected 3-D maps, it was necessary to explain to scenario users—especially engineers who often use median maps—the differences, advantages, and disadvantages of the two approaches. We used authority, empirical evidence, and theory to support our choice. We prefaced our explanation with SAFRR's policy of using the best available earth science, and cited the credentials of the maps' developers and the reputation of the journal in which they published the maps. We cited recorded examples from past earthquakes of extreme ground motions that are like those in the scenario map. We explained the maps on theoretical grounds as well, explaining well established causes of variability: directivity, basin effects, and source parameters. The largest mapped motions relate to potentially unfamiliar extreme-value theory, so we used analogies to human longevity and the average age of the oldest person in samples of

  8. Laboratory rotational ground state transitions of NH3D+ and CF+

    NASA Astrophysics Data System (ADS)

    Stoffels, A.; Kluge, L.; Schlemmer, S.; Brünken, S.

    2016-09-01

    Aims: This paper reports accurate laboratory frequencies of the rotational ground state transitions of two astronomically relevant molecular ions, NH3D+ and CF+. Methods: Spectra in the millimetre-wave band were recorded by the method of rotational state-selective attachment of He atoms to the molecular ions stored and cooled in a cryogenic ion trap held at 4 K. The lowest rotational transition in the A state (ortho state) of NH3D+ (JK = 10-00), and the two hyperfine components of the ground state transition of CF+ (J = 1-0) were measured with a relative precision better than 10-7. Results: For both target ions, the experimental transition frequencies agree with recent observations of the same lines in different astronomical environments. In the case of NH3D+ the high-accuracy laboratory measurements lend support to its tentative identification in the interstellar medium. For CF+ the experimentally determined hyperfine splitting confirms previous quantum-chemical calculations and the intrinsic spectroscopic nature of a double-peaked line profile observed in the J = 1-0 transition towards the Horsehead photon-dominated region (PDR).

  9. Ground water in Oklahoma

    USGS Publications Warehouse

    Leonard, A.R.

    1960-01-01

    One of the first requisites for the intelligent planning of utilization and control of water and for the administration of laws relating to its use is data on the quantity, quality, and mode of occurrence of the available supplies. The collection, evaluation and interpretation, and publication of such data are among the primary functions of the U.S. Geological Survey. Since 1895 the Congress has made appropriations to the Survey for investigation of the water resources of the Nation. In 1929 the Congress adopted the policy of dollar-for-dollar cooperation with the States and local governmental agencies in water-resources investigations of the U.S. Geological Survey. In 1937 a program of ground-water investigations was started in cooperation with the Oklahoma Geological Survey, and in 1949 this program was expanded to include cooperation with the Oklahoma Planning and Resources Board. In 1957 the State Legislature created the Oklahoma Water Resources Board as the principal State water agency and it became the principal local cooperator. The Ground Water Branch of the U.S. Geological Survey collects, analyzes, and evaluates basic information on ground-water resources and prepares interpretive reports based on those data. Cooperative ground-water work was first concentrated in the Panhandle counties. During World War II most work was related to problems of water supply for defense requirements. Since 1945 detailed investigations of ground-water availability have been made in 11 areas, chiefly in the western and central parts of the State. In addition, water levels in more than 300 wells are measured periodically, principally in the western half of the State. In Oklahoma current studies are directed toward determining the source, occurrence, and availability of ground water and toward estimating the quantity of water and rate of replenishment to specific areas and water-bearing formations. Ground water plays an important role in the economy of the State. It is

  10. Reconstructing 3D coastal cliffs from airborne oblique photographs without ground control points

    NASA Astrophysics Data System (ADS)

    Dewez, T. J. B.

    2014-05-01

    Coastal cliff collapse hazard assessment requires measuring cliff face topography at regular intervals. Terrestrial laser scanner techniques have proven useful so far but are expensive to use either through purchasing the equipment or through survey subcontracting. In addition, terrestrial laser surveys take time which is sometimes incompatible with the time during with the beach is accessible at low-tide. By comparison, structure from motion techniques (SFM) are much less costly to implement, and if airborne, acquisition of several kilometers of coastline can be done in a matter of minutes. In this paper, the potential of GPS-tagged oblique airborne photographs and SFM techniques is examined to reconstruct chalk cliff dense 3D point clouds without Ground Control Points (GCP). The focus is put on comparing the relative 3D point of views reconstructed by Visual SFM with their synchronous Solmeta Geotagger Pro2 GPS locations using robust estimators. With a set of 568 oblique photos, shot from the open door of an airplane with a triplet of synchronized Nikon D7000, GPS and SFM-determined view point coordinates converge to X: ±31.5 m; Y: ±39.7 m; Z: ±13.0 m (LE66). Uncertainty in GPS position affects the model scale, angular attitude of the reference frame (the shoreline ends up tilted by 2°) and absolute positioning. Ground Control Points cannot be avoided to orient such models.

  11. Ground Signatures of EMIC Waves obtained From a 3D Global Wave Model

    NASA Astrophysics Data System (ADS)

    Rankin, R.; Sydorenko, D.; Zong, Q.; Zhang, L.

    2016-12-01

    EMIC waves generated in the inner magnetosphere are important drivers of radiation belt particle loss. Van Allen Probes and ground observations of EMIC waves suggest that localized magnetospheric sources inject waves that are guided along geomagnetic field lines and then reflected and refracted in the low altitude magnetosphere [Kim, E.-H., and J. R. Johnson (2016), Geophys. Res. Lett., 43, 13-21, doi:10.1002/2015GL066978] before entering the ionosphere. The waves then spread horizontally within the F-region waveguide and propagate to the ground. To understand the observed properties of EMIC waves, a global 3D model of ULF waves in Earth's magnetosphere, ionosphere, and neutral atmosphere has been developed. The simulation domain extends from Earth's surface to a spherical boundary a few tens of thousands of km in radius. The model uses spherical coordinates and incorporates an overset Yin-Yang grid that eliminates the singularity at the polar axis and improves uniformity of the grid in the polar areas [Kageyama, A., and T. Sato (2004), Geochem. Geophys. Geosyst., 5, Q09005, doi:10.1029/2004GC000734]. The geomagnetic field in the model is general, but is dipole in this study. The plasma is described as a set of electron and multiple species ion conducting fluids. Realistic 3D density profiles of various ion species as well as thermospheric parameters are provided by the Canadian Ionosphere Atmosphere Model (C-IAM) [Martynenko O.V. et al. (2014), J. Atmos. Solar-Terr. Phys., 120, 51-61, doi:10.1016/j.jastp.2014.08.014]. The global ULF wave model is applied to study propagation of EMIC waves excited in the equatorial plane near L=7. Wave propagation along field lines, reflection and refraction in the zone of critical frequencies, and further propagation through the ionosphere to the ground are discussed.

  12. Ground reaction force and 3D biomechanical characteristics of walking in short-leg walkers.

    PubMed

    Zhang, Songning; Clowers, Kurt G; Powell, Douglas

    2006-12-01

    Short-leg walking boots offer several advantages over traditional casts. However, their effects on ground reaction forces (GRF) and three-dimensional (3D) biomechanics are not fully understood. The purpose of the study was to examine 3D lower extremity kinematics and joint dynamics during walking in two different short-leg walking boots. Eleven (five females and six males) healthy subjects performed five level walking trials in each of three conditions: two testing boot conditions, Gait Walker (DeRoyal Industries, Inc.) and Equalizer (Royce Medical Co.), and one pair of laboratory shoes (Noveto, Adidas). A force platform and a 6-camera Vicon motion analysis system were used to collect GRFs and 3D kinematic data during the testing session. A one-way repeated measures analysis of variance (ANOVA) was used to evaluate selected kinematic, GRF, and joint kinetic variables (p<0.05). The results revealed that both short-leg walking boots were effective in minimizing ankle eversion and hip adduction. Neither walker increased the bimodal vertical GRF peaks typically observed in normal walking. However, they did impose a small initial peak (<1BW) earlier in the stance phase. The Gait Walker also exhibited a slightly increased vertical GRF during midstance. These characteristics may be related to the sole materials/design, the restriction of ankle movements, and/or the elevated heel heights of the tested walkers. Both walkers appeared to increase the demand on the knee extensors while they decreased the demand of the knee and hip abductors based on the joint kinetic results.

  13. Velocity and Density Models Incorporating the Cascadia Subduction Zone for 3D Earthquake Ground Motion Simulations

    USGS Publications Warehouse

    Stephenson, William J.

    2007-01-01

    INTRODUCTION In support of earthquake hazards and ground motion studies in the Pacific Northwest, three-dimensional P- and S-wave velocity (3D Vp and Vs) and density (3D rho) models incorporating the Cascadia subduction zone have been developed for the region encompassed from about 40.2?N to 50?N latitude, and from about -122?W to -129?W longitude. The model volume includes elevations from 0 km to 60 km (elevation is opposite of depth in model coordinates). Stephenson and Frankel (2003) presented preliminary ground motion simulations valid up to 0.1 Hz using an earlier version of these models. The version of the model volume described here includes more structural and geophysical detail, particularly in the Puget Lowland as required for scenario earthquake simulations in the development of the Seattle Urban Hazards Maps (Frankel and others, 2007). Olsen and others (in press) used the model volume discussed here to perform a Cascadia simulation up to 0.5 Hz using a Sumatra-Andaman Islands rupture history. As research from the EarthScope Program (http://www.earthscope.org) is published, a wealth of important detail can be added to these model volumes, particularly to depths of the upper-mantle. However, at the time of development for this model version, no EarthScope-specific results were incorporated. This report is intended to be a reference for colleagues and associates who have used or are planning to use this preliminary model in their research. To this end, it is intended that these models will be considered a beginning template for a community velocity model of the Cascadia region as more data and results become available.

  14. Inverse modeling of InSAR and ground leveling data for 3D volumetric strain distribution

    NASA Astrophysics Data System (ADS)

    Gallardo, L. A.; Glowacka, E.; Sarychikhina, O.

    2015-12-01

    Wide availability of modern Interferometric Synthetic aperture Radar (InSAR) data have made possible the extensive observation of differential surface displacements and are becoming an efficient tool for the detailed monitoring of terrain subsidence associated to reservoir dynamics, volcanic deformation and active tectonism. Unfortunately, this increasing popularity has not been matched by the availability of automated codes to estimate underground deformation, since many of them still rely on trial-error subsurface model building strategies. We posit that an efficient algorithm for the volumetric modeling of differential surface displacements should match the availability of current leveling and InSAR data and have developed an algorithm for the joint inversion of ground leveling and dInSAR data in 3D. We assume the ground displacements are originated by a stress free-volume strain distribution in a homogeneous elastic media and determined the displacement field associated to an ensemble of rectangular prisms. This formulation is then used to develop a 3D conjugate gradient inversion code that searches for the three-dimensional distribution of the volumetric strains that predict InSAR and leveling surface displacements simultaneously. The algorithm is regularized applying discontinuos first and zero order Thikonov constraints. For efficiency, the resulting computational code takes advantage of the resulting convolution integral associated to the deformation field and some basic tools for multithreading parallelization. We extensively test our algorithm on leveling and InSAR test and field data of the Northwest of Mexico and compare to some feasible geological scenarios of underground deformation.

  15. 3-D Ground Displacement Monitoring of very fast-moving Landslides in Emergency Scenario

    NASA Astrophysics Data System (ADS)

    Casu, Francesco; Manconi, Andrea; Bonano, Manuela; De Luca, Claudio; Elefante, Stefano

    2014-05-01

    On December 3rd, 2013, a large and fast-moving landslide phenomena, which occurred in South-West of Montescaglioso town (southern Italy) after some days of intense raining, caused ground displacements on the order of several meters. The mass wasting involved an important freeway connection disrupting more than 500 meters of the route and some isolated buildings. In this work we present a case study of application of SAR remote sensing techniques for retrieving ground displacement field in a landslide emergency scenario. To this aim, thanks to the availability of ascending and descending COSMO-SkyMed (CSK) satellite acquisitions, we first applied the DInSAR technique (Massonnet et al., 1993) to both datasets, for generating differential interferograms across the investigated event. In particular, two data pairs (one ascending and one descending) involving pre- and post-event epochs and approximately spanning the same time interval were identified. Unfortunately, the DInSAR analysis produced unsatisfactory results, because of the excessive phase noise within the area of interest, mainly related to the fast-moving deformation pattern (several meters) and also to the presence of vegetation. To overcome the above mentioned limitations, the amplitude-based Pixel Offset (PO) technique (Fialko and Simons, 2001) was applied to the previous identified CSK data pairs. In this case, the PO technique allowed us to retrieve the projection of the surface displacements across and along the satellite's track (range and azimuth, respectively) for both the ascending and descending orbits. Then, by properly combining these 2-D maps of the measured surface movements, we also retrieved the 3-D ground deformation pattern, i.e. the North, East and Vertical displacement components. The ground displacements have a main SSE component, with values exceeding 10 meters. Moreover, large subsidence values were identified in those areas experiencing the largest damages, as well as a clear uplift

  16. Rupture dynamics and ground motion from 3-D rough-fault simulations

    NASA Astrophysics Data System (ADS)

    Shi, Zheqiang; Day, Steven M.

    2013-03-01

    perform three-dimensional (3-D) numerical calculations of dynamic rupture along non-planar faults to study the effects of fault roughness on rupture propagation and resultant ground motion. The fault roughness model follows a self-similar fractal distribution over length scales spanning three orders of magnitude, from ~102 to ~105 m. The fault is governed by a strongly rate-weakening friction, and the bulk material is subject to Drucker-Prager viscoplasticity. Fault roughness promotes the development of self-healing rupture pulses and a heterogeneous distribution of fault slip at the free surface and at depth. The inelastic deformation, generated by the large dynamic stress near rupture fronts, occurs in a narrow volume around the fault with heterogeneous thickness correlated to local roughness slopes. Inelastic deformation near the free surface, however, is induced by the stress waves originated from dynamic rupture at depth and spreads to large distances (>10 km) away from the fault. The present simulations model seismic wave excitation up to ~10 Hz with rupture lengths of ~100 km, permitting comparisons with empirical studies of ground-motion intensity measures of engineering interest. Characteristics of site-averaged synthetic response spectra, including the distance and period dependence of the median values, absolute level, and intra-event standard deviation, are comparable to appropriate empirical estimates throughout the period range 0.1-3.0 s. This class of model may provide a viable representation of the ground-motion excitation process over a wide frequency range in a large spatial domain, with potential applications to the numerical prediction of source- and path-specific effects on earthquake ground motion.

  17. Evaluation of 3D Ground Penetrating Radar Efficiency for Abandoned Tailings Pond Internal Structure Analysis and Risk Assessment

    NASA Astrophysics Data System (ADS)

    Cortada, Unai; Martínez, Julián; Hidalgo, Mª Carmen; Rey, Javier

    2017-04-01

    Evaluation of 3D Ground Penetrating Radar Efficiency for Abandoned Tailings Pond Internal Structure Analysis and Risk Assessment Abandoned tailings ponds constitute a severe environmental problem in old Pb mining districts due to their high contents in metallic and semi-metallic elements. In most of the cases, there is a lack of information about the construction procedures and the previous environmental situation, which hinders the environmental risk evaluation. In these cases, Ground Penetrating Radar (GPR) could be an interesting technique to analyze the internal structure of the tailings ponds and detect vulnerable zones for leaching processes. Consequently, the GPR could help in the abandoned tailings ponds environmental risk assessment. In this study, a GPR 3D campaign was carried out with a 250 MHz frequency antenna in order to evaluate the efficiency of this technique in both the analysis of internal structures and the environmental risk assessment. Subsequently, 2D and 3D models were undertaken to represent graphically the obtained results. The studied tailings pond is located in the Guadiel river bank, a water course draining the mining district of Linares, Spain. The dam is 150 m length and 80 m width. The GPR 3D was done in a selected area near the central part of the pond. The analyzed grid was 25x50 m and the spacing of the slides was 1 m. The study revealed that the contact between the tailings and the substratum is located at 2.5 m. No intermediate layer was found, which means that the tailings pond was heightened on the fluvial terrace without any insulation system. Inside the first meter of the pond, a cross stratification was identified. The orientation of those laminations changed with the depth, which means that the stockpiling was performed from the different sides of the tailings pond. Furthermore, the direction of these stratifications is slightly concentric to the middle of the dam which could be associated with a central drainage system

  18. Photographing Internal Fractures of the Archaeological Statues with 3D Visualization of Ground Penetrating Radar Data

    NASA Astrophysics Data System (ADS)

    Kadioglu, S.; Kadioglu, Y. K.

    2009-04-01

    PHOTOGRAPHING INTERNAL FRACTURES OF THE ARCHAEOLOGICAL STATUES WITH 3D VISUALIZATION OF GROUND PENETRATING RADAR DATA Selma KADIOGLU1 and Yusuf K. KADIOGLU2 1Ankara University, Faculty of Engineering, Department of Geophysical Engineering, 06100 Tandogan/ANKARA-TURKEY kadioglu@eng.ankara.edu.tr 2Ankara University, Faculty of Engineering, Department of Geological Engineering, 06100 Tandogan/ANKARA-TURKEY kadi@eng.ankara.edu.tr The aim of the study is to illustrate a new approach to image the discontinuities in the archaeological statues before restoration studies using ground penetrating radar (GPR) method. The method was successfully applied to detect and map the fractures and cavities of the two monument groups and lion statues in Mustafa Kemal ATATURK's tumb (ANITKABIR) in Ankara-Turkey. The tumb, which has been started to build in 1944 and completed in 1953, represents Turkish people and Ataturk, who is founder of the Republic of Turkey. Therefore this monument is very important for Turkish people. The monument groups and lion statues have been built from travertine rocks. These travertine have vesicular textures with the percent of 12. They have been mainly composed of calcite, aragonite with rare amount of plant relict and clay minerals. The concentrations of Fe, Mg, Cl and Mn may lead to verify their colours changing from white through pale green to beige. The atmospheric contamination of Ankara has been caused to cover some parts of the surface of these travertine with a thin film of Pb as blackish in colour. The micro fractures have been observed specially at the rim of the vesicular of the rocks by the polarizing microscope. Parallel two dimensional (2D) GPR profile data with 10cm profile space were acquired by RAMAC CU II system with 1600 MHz shielded antenna on the monument groups (three women, three men and 24 lion statues) and then a three dimensional (3D) data volume were built using parallel 2D GPR data. Air-filled fractures and cavities in the

  19. 3D Modeling of Landslide in Open-pit Mining on Basis of Ground-based LIDAR Data

    NASA Astrophysics Data System (ADS)

    Hu, H.; Fernandez-Steeger, T. M.; Azzam, R.; Arnhardt, C.

    2009-04-01

    Slope stability is not only an important problem which is related to production and safety in open-pit mining, but also very complex task. There are three main reasons which affect the slope stability as follows: geotechnical factors: Geological structure, lithologic characteristics, water, cohesion, friction, etc.; climate factors: Rainfall and temperature; and external factors: Open-pit mining process, explosion vibration, dynamic load, etc.. The 3rd reason, as a specially one in open-pit mining, not only causes some dynamic problems but also induces the fast geometry changing which must be considered in the following research using numerical simulation and stability analysis. Recently, LIDAR technology has been applied in many fields and places in the world wide. Ground-based LIDAR technology with high accuracy up to 3mm increasingly accommodates to monitoring landslides and detecting changing. LIDAR data collection and preprocessing research have been carried out by Department of Engineering Geology and Hydrogeology at RWTH Aachen University. LIDAR data, so-called a point-cloud of mass data in high density can be obtained in short time for the sensitive open-pit mining area by using ground-based LIDAR. To obtain a consistent surface model, it is necessary to set up multiple scans with the ground-based LIDAR. The framework of data preprocessing which can be implemented by Poly-Works is introduced as follows: gross error detection and elimination, integration of reference frame, model fusion of different scans (re-sampled in overlap region), data reduction without removing the useful information which is a challenge and research front in LIDAR data processing. After data preprocessing, 3D surface model can be directly generated in Poly-Works or generated in other software by building the triangular meshes. The 3D surface landslide model can be applied to further researches such as: real time landslide geometry monitoring due to the fast data collection and

  20. 3D full-Stokes modeling of the grounding line dynamics of Thwaites Glacier, West Antarctica

    NASA Astrophysics Data System (ADS)

    Yu, H.; Rignot, E. J.; Morlighem, M.; Seroussi, H. L.

    2016-12-01

    Thwaites Glacier (TG) is the broadest and second largest ice stream in the West Antarctica. Satellite observations have revealed rapid grounding line retreat and mass loss of this glacier in the past few decades, which has been attributed to the enhanced basal melting in the Amundsen Sea Embayment. With a retrograde bed configuration, TG is on the verge of collapse according to the marine ice sheet instability theory. Here, we use the UCI/JPL Ice Sheet System Model (ISSM) to simulate the grounding line position of TG to determine its stability, rate of retreat and sensitivity to enhanced basal melting using a three-dimensional full-Stokes numerical model. Simulations with simplified models (Higher Order (HO), and Shelfy-Stream Approximation (SSA)) are also conducted for comparison. We first validate our full Stokes model by conducting MISMIP3D experiments. Then we applied the model to TG using new bed elevation dataset combining IceBridge (OIB) gravity data, OIB ice thickness, ice flow vectors from interferometry and a mass conservation method at 450 m spacing. Basal friction coefficient and ice rheology of floating ice are inferred to match observed surface velocity. We find that the grounding line is capable of retreating at rate of 1km/yr under current forcing and that the glacier's sensitivity to melt is higher in the Stokes model than HO or SSA, which means that projections using SSA or HO might underestimate the future rate of retreat of the glacier. This work has been performed at UC Irvine and Caltech's Jet Propulsion Laboratory under a contract with NASA's Cryospheric Science Program.

  1. 3-D Waveguide Effects of Topographical Structural Variation on Full Waveform Propagation: 3-D Finite Difference Modeling Comparisons with Field Data From Yuma Proving Ground, Arizona

    NASA Astrophysics Data System (ADS)

    Anderson, T. S.; Miller, R.; Greenfield, R.; Fisk, D.

    2002-12-01

    The propagation of seismic waves through regions of complex topography is not thoroughly understood. Surface waves, are of particular interest, as they are large in amplitude and can characterize the source depth, magnitude, and frequency content. The amplitude and frequency content of seismic waves that propagate in regions with large topographical variations are affected by both the scattering and blockage of the wave energy. The ability to predict the 3-d scattering due to topography will improve the understanding of both regional scale surface wave magnitudes, and refine surface wave discriminants as well as at the local scale (<2 km ) where it will aid in the development of rule of thumb guide lines for array sensor placement for real time sensing technologies. Ideally, when validating the numerical accuracy of a propagation model against field data, the input geologic parameters would be known and thus eliminates geology as a source of error in the calculation. In March of 2001, Kansas Geological Survey (KGS) performed a detailed seismic site characterization at the Smart Weapons Test Range, Yuma Proving Ground, Arizona. The result of the KGS characterization study is a high-resolution 3-d model that is used in our seismic simulations. The velocities Vs, Vp are calculated by tomography and refraction, attenuation coefficients estimated from the surface wave and from p-waves and are provided in a model with attributes resolved in 3-d to 0.5 meters. In the present work, we present comparisons of synthetic data with seismic data collected at the Smart Weapons Test Range to benchmark the accuracy achieved in simulating 3-d wave propagation in the vicinity of a topographical anomaly (trench). Synthetic seismograms are generated using a 3-d 8th order staggered grid visco-elastic finite difference code that accounts for topography. The geologic model is based on the Yuma site characterization. The size of these calculations required use of the DoD High Performance

  2. GROUND WATER CONTAMINATION

    SciTech Connect

    Unknown

    1999-09-01

    As required by the terms of the above referenced grant, the following summary serves as the Final Report for that grant. The grant relates to work performed at two separate sites, the Hoe Creek Underground Coal Gasification Site south of Gillette, Wyoming, and the Rock Springs In-Situ Oil Shale Retort Site near Rock Springs, Wyoming. The primary concern to the State of Wyoming at each site is ground water contamination (the primary contaminants of concern are benzene and related compounds), and the purpose of the grant has been to provide tiding for a Geohydrologist at the appropriate State agency, specifically the Land Quality Division (LQD) of the Wyoming Department of Environmental Quality. The LQD Geohydrologist has been responsible for providing technical and regulatory support to DOE for ground water remediation and subsequent surface reclamation. Substantial progress has been made toward remediation of the sites, and continuation of LQD involvement in the remediation and reclamation efforts is addressed.

  3. Quantification of Ground Motion Reductions by Fault Zone Plasticity with 3D Spontaneous Rupture Simulations

    NASA Astrophysics Data System (ADS)

    Roten, D.; Olsen, K. B.; Cui, Y.; Day, S. M.

    2015-12-01

    We explore the effects of fault zone nonlinearity on peak ground velocities (PGVs) by simulating a suite of surface rupturing earthquakes in a visco-plastic medium. Our simulations, performed with the AWP-ODC 3D finite difference code, cover magnitudes from 6.5 to 8.0, with several realizations of the stochastic stress drop for a given magnitude. We test three different models of rock strength, with friction angles and cohesions based on criteria which are frequently applied to fractured rock masses in civil engineering and mining. We use a minimum shear-wave velocity of 500 m/s and a maximum frequency of 1 Hz. In rupture scenarios with average stress drop (~3.5 MPa), plastic yielding reduces near-fault PGVs by 15 to 30% in pre-fractured, low-strength rock, but less than 1% in massive, high quality rock. These reductions are almost insensitive to the scenario earthquake magnitude. In the case of high stress drop (~7 MPa), however, plasticity reduces near-fault PGVs by 38 to 45% in rocks of low strength and by 5 to 15% in rocks of high strength. Because plasticity reduces slip rates and static slip near the surface, these effects can partially be captured by defining a shallow velocity-strengthening layer. We also perform a dynamic nonlinear simulation of a high stress drop M 7.8 earthquake rupturing the southern San Andreas fault along 250 km from Indio to Lake Hughes. With respect to the viscoelastic solution (a), nonlinearity in the fault damage zone and in near-surface deposits would reduce long-period (> 1 s) peak ground velocities in the Los Angeles basin by 15-50% (b), depending on the strength of crustal rocks and shallow sediments. These simulation results suggest that nonlinear effects may be relevant even at long periods, especially for earthquakes with high stress drop.

  4. Three-body problem in 3D space: ground state, (quasi)-exact-solvability

    NASA Astrophysics Data System (ADS)

    Turbiner, Alexander V.; Miller, Willard, Jr.; Escobar-Ruiz, Adrian M.

    2017-05-01

    We study aspects of the quantum and classical dynamics of a 3-body system in 3D space with interaction depending only on mutual distances. The study is restricted to solutions in the space of relative motion which are functions of mutual distances only. It is shown that the ground state (and some other states) in the quantum case and the planar trajectories in the classical case are of this type. The quantum (and classical) system for which these states are eigenstates is found and its Hamiltonian is constructed. It corresponds to a three-dimensional quantum particle moving in a curved space with special metric. The kinetic energy of the system has a hidden sl(4, R) Lie (Poisson) algebra structure, alternatively, the hidden algebra h (3) typical for the H 3 Calogero model. We find an exactly solvable three-body generalized harmonic oscillator-type potential as well as a quasi-exactly-solvable three-body sextic polynomial type potential; both models have an extra integral.

  5. Vegetation Structure and 3-D Reconstruction of Forests Using Ground-Based Echidna® Lidar

    NASA Astrophysics Data System (ADS)

    Strahler, A. H.; Yao, T.; Zhao, F.; Yang, X.

    2009-12-01

    A ground-based, scanning, near-infrared lidar, the Echidna® validation instrument (EVI), built by CSIRO Australia, retrieves structural parameters of forest stands rapidly and accurately, and by merging multiple scans into a single point cloud provides 3-D stand reconstructions. Echidna lidar technology scans with pulses of light at 1064 nm wavelength and digitizes the light returns sufficiently finely to recover and distinguish the differing shapes of return pulses as they are scattered by leaves and trunks or larger branches. Instrument deployments in the New England region in 2007 and 2009 and in the southern Sierra Nevada of California in 2008 provided the opportunity to test the ability of the instrument to retrieve tree diameters, stem count density (stems/ha), basal area, and above-ground woody biomass from single scans at points beneath the forest canopy. In New England in 2007, mean parameters retrieved from five scans located within six 1-ha stand sites match manually-measured parameters with values of R2 = 0.94-0.99. Processing the scans to retrieve leaf area index (LAI) provided values within the range of those retrieved with other optical instruments and hemispherical photography. Foliage profiles, which measure leaf area with canopy height, showed distinctly different shapes for the stands, depending on species composition and age structure. Stand heights, obtained from foliage profiles, were not significantly different from RH100 values observed by the Laser Vegetation Imaging Sensor in 2003. Data from the California 2008 and New England 2009 deployments were still being processed at the time of abstract submission. With further hardware and software development, Echidna® technology will provide rapid and accurate measurements of forest canopy structure that can replace manual field measurements, leading to more rapid and more accurate calibration and validation of structure mapping techniques using airborne and spaceborne remote sensors. Three

  6. Estimating porosity with ground-penetrating radar reflection tomography: A controlled 3-D experiment at the Boise Hydrogeophysical Research Site

    NASA Astrophysics Data System (ADS)

    Bradford, John H.; Clement, William P.; Barrash, Warren

    2009-04-01

    To evaluate the uncertainty of water-saturated sediment velocity and porosity estimates derived from surface-based, ground-penetrating radar reflection tomography, we conducted a controlled field experiment at the Boise Hydrogeophysical Research Site (BHRS). The BHRS is an experimental well field located near Boise, Idaho. The experimental data set consisted of 3-D multioffset radar acquired on an orthogonal 20 × 30 m surface grid that encompassed a set of 13 boreholes. Experimental control included (1) 1-D vertical velocity functions determined from traveltime inversion of vertical radar profiles (VRP) and (2) neutron porosity logs. We estimated the porosity distribution in the saturated zone using both the Topp and Complex Refractive Index Method (CRIM) equations and found the CRIM estimates in better agreement with the neutron logs. We found that when averaged over the length of the borehole, surface-derived velocity measurements were within 5% of the VRP velocities and that the porosity differed from the neutron log by less than 0.05. The uncertainty, however, is scale dependent. We found that the standard deviation of differences between ground-penetrating-radar-derived and neutron-log-derived porosity values was as high as 0.06 at an averaging length of 0.25 m but decreased to less than 0.02 at length scale of 11 m. Additionally, we used the 3-D porosity distribution to identify a relatively high-porosity anomaly (i.e., local sedimentary body) within a lower-porosity unit and verified the presence of the anomaly using the neutron porosity logs. Since the reflection tomography approach requires only surface data, it can provide rapid assessment of bulk hydrologic properties, identify meter-scale anomalies of hydrologic significance, and may provide input for other higher-resolution measurement methods.

  7. Detection of 3D tree root systems using high resolution ground penetration radar

    NASA Astrophysics Data System (ADS)

    Altdorff, D.; Honds, M.; Botschek, J.; Van Der Kruk, J.

    2014-12-01

    Knowledge of root systems and its distribution are important for biomass estimation as well as for the prevention of subsurface distribution network damages. Ground penetration radar (GPR) is a promising technique that enables a non-invasive imaging of tree roots. Due to the polarisation-dependent reflection coefficients and complicated three-dimensional root structure, accurate measurements with perpendicularly polarized antennas are needed. In this study, we show GPR data from two planes and one chestnut at two locations with different soil conditions. Perpendicular 10 x 10 cm grid measurements were made with a shielded 250 MHz antenna in combination with a high precision self-tracking laser theodolite that provides geo-referenced traces with a spatial resolution of ~ 2 cm. After selecting potential root hyperbolas within the perpendicular GPR profiles, the corresponding three-dimensional coordinates were extracted and visualized in planar view to reveal any linear structure that indicates a possible tree root. The coordinates of the selected linear structures were projected back to the surface by means of the laser-theodolite to indicate the locations for groundtruthing. Additionally, we interpolated the measured data into a 3D cube where time slices confirmed the locations of linear reflection events. We validated the indicated predictions by excavation of the soil with a suction dredge. Subsequent georeferencing of the true root distribution and comparison with the selected linear events showed that the approach was able to identify the precise position of roots with a diameter between 3 and 10 cm and a depth of up to 70 cm. However, not all linear events were roots; also mouse channels were found in these depths, since they also generate GPR hyperbolas aligned in linear structures. Roots at a second location at depths of 1 to 1.20 m did not generate identifiable hyperboles, which was probably due to an increased electrical conductivity below 86 cm depth. The

  8. Kinematic ground motion simulations on rough faults including effects of 3D stochastic velocity perturbations

    USGS Publications Warehouse

    Graves, Robert; Pitarka, Arben

    2016-01-01

    We describe a methodology for generating kinematic earthquake ruptures for use in 3D ground‐motion simulations over the 0–5 Hz frequency band. Our approach begins by specifying a spatially random slip distribution that has a roughly wavenumber‐squared fall‐off. Given a hypocenter, the rupture speed is specified to average about 75%–80% of the local shear wavespeed and the prescribed slip‐rate function has a Kostrov‐like shape with a fault‐averaged rise time that scales self‐similarly with the seismic moment. Both the rupture time and rise time include significant local perturbations across the fault surface specified by spatially random fields that are partially correlated with the underlying slip distribution. We represent velocity‐strengthening fault zones in the shallow (<5  km) and deep (>15  km) crust by decreasing rupture speed and increasing rise time in these regions. Additional refinements to this approach include the incorporation of geometric perturbations to the fault surface, 3D stochastic correlated perturbations to the P‐ and S‐wave velocity structure, and a damage zone surrounding the shallow fault surface characterized by a 30% reduction in seismic velocity. We demonstrate the approach using a suite of simulations for a hypothetical Mw 6.45 strike‐slip earthquake embedded in a generalized hard‐rock velocity structure. The simulation results are compared with the median predictions from the 2014 Next Generation Attenuation‐West2 Project ground‐motion prediction equations and show very good agreement over the frequency band 0.1–5 Hz for distances out to 25 km from the fault. Additionally, the newly added features act to reduce the coherency of the radiated higher frequency (f>1  Hz) ground motions, and homogenize radiation‐pattern effects in this same bandwidth, which move the simulations closer to the statistical characteristics of observed motions as illustrated by comparison with recordings from

  9. Cooperative 3D and 2D mapping with heterogenous ground robots

    NASA Astrophysics Data System (ADS)

    Rogers, John G., III; Baran, David; Stump, Ethan; Young, Stuart; Christensen, Henrik I.

    2012-06-01

    Efficient and accurate 3D mapping is desirable in disaster recovery as well as urban warfare situations. The speed with which these maps can be generated is vital to provide situational awareness in these situations. A team of mobile robots can work together to build maps more quickly. We present an algorithm by which a team of mobile robots can merge 2D and 3D measurements to build a 3D map, together with experiments performed at a military test facility.

  10. A 3D finite element simulation model for TBM tunnelling in soft ground

    NASA Astrophysics Data System (ADS)

    Kasper, Thomas; Meschke, Günther

    2004-12-01

    A three-dimensional finite element simulation model for shield-driven tunnel excavation is presented. The model takes into account all relevant components of the construction process (the soil and the ground water, the tunnel boring machine with frictional contact to the soil, the hydraulic jacks, the tunnel lining and the tail void grouting). The paper gives a detailed description of the model components and the stepwise procedure to simulate the construction process. The soil and the grout material are modelled as saturated porous media using a two-field finite element formulation. This allows to take into account the groundwater, the grouting pressure and the fluid interaction between the soil and slurry at the cutting face and between the soil and grout around the tail void. A Cam-Clay plasticity model is used to describe the material behaviour of cohesive soils. The cementitious grouting material in the tail void is modelled as an ageing elastic material with time-dependent stiffness and permeability. To allow for an automated computation of arbitrarily long and also curvilinear driving paths with suitable finite element meshes, the simulation procedure has been fully automated. The simulation of a tunnel advance in soft cohesive soil below the ground water table is presented and the results are compared with measurements taken from the literature. Copyright

  11. Imaging of Subglacial Meltwater Channels Using 3D Ground-Penetrating Radar

    NASA Astrophysics Data System (ADS)

    Irving, J.; Baron, L.; Ruttimann, S.; Lane, S. N.

    2016-12-01

    Knowledge regarding the spatial distribution and evolution of subglacial meltwater channels is critical for understanding and modeling subglacial hydrology and glacier flow dynamics. Although field experiments such as dye tracer tests can provide useful data to constrain overall channel network characteristics, the only hope of obtaining definitive information regarding the location of subglacial channels, aside from direct observation where possible, is through the use of geophysical methods. In particular, ground-penetrating radar (GPR) has attracted much interest in cryospheric studies due to its excellent propagation characteristics in ice and its potential for high-resolution reflection imaging. Here, we present the results of 3D GPR reflection imaging conducted on the Haut Glacier d'Arolla, a temperate alpine glacier located in the Val d'Herens, Switzerland. In August 2015, a 100 x 100 m region near the glacier terminus was surveyed using a recently developed real-time-sampling GPR instrument with 70 MHz antennas. GPR survey lines were spaced 1 m apart and accurate positioning on the glacier was achieved using real-time differential GPS. After basic processing, the corresponding GPR data cube showed clearly the reflection originating from the ice-bedrock contact at the base of the glacier, which was manually picked and used to "flatten" the data on this interface. Subsequent analysis of the instantaneous attributes of the glacier bed reflection clearly reveals a network of subglacial channels, the positions of which are consistent with the inferred bedrock topography as well as the observed location of glacial outlet streams. Interestingly, one of the major identified channels was found to correspond exactly with the position of a recent and extensive fracture located on the glacier surface, which opened approximately two months after the GPR survey was conducted.

  12. Ground penetrating radar and microwave tomography 3D applications for the deck evaluation of the Musmeci bridge in Potenza, Italy

    NASA Astrophysics Data System (ADS)

    Bavusi, Massimo; Soldovieri, Francesco; Di Napoli, Rosario; Loperte, Antonio; Di Cesare, Antonio; Carlo Ponzo, Felice; Lapenna, Vincenzo

    2011-09-01

    An extensive experimental and numerical investigation has been carried out to assess the status of the 'Ponte sul Basento' (1967-1976), in the town of Potenza (Basilicata region, southern Italy), better known as the Musmeci bridge. Architecturally, the bridge is a considerable reinforced 20th century concrete structure that was designed and built by the Italian architect Sergio Musmeci (1926-1981). Moreover, the bridge represents an important element of the infrastructural network, linking the city centre to the Potenza-Sicignano highway, crossing the Basento river and the railway close to the main train station of the city. Recently, due to ageing and continuous and significant traffic, the bridge started to be affected by several problems such as water infiltration. Within the presented study, a widespread ground penetrating radar (GPR) survey has been designed to investigate the geometrical characteristics of the bridge deck (Gerber saddles, internal stiffening walls, pillar supports) and detect the presence of defects or damage due to water infiltration and traffic fatigue. Concerning this, a 900 MHz 3D GPR survey has been performed along a zone of one of the lanes on the road surface. Moreover, a second 1500 MHz 3D survey has been carried out at the bottom of the bridge deck in order to gain detailed information about an important structural element of the bridge, the Gerber saddle. Both results have been processed following two approaches: the first a classical time-domain processing session based on commercial software and the use of migration; the second in microwave tomography, an advanced frequency domain automatic PC-based inversion algorithm. In this paper, we present a comparative interpretation of both kinds of processed results, and provide considerations about the investigated structures.

  13. Modeling Airport Ground Operations using Discrete Event Simulation (DES) and X3D Visualization

    DTIC Science & Technology

    2008-03-01

    studies, because it offers a number of features as for example: 12 1. Open source 2. Character animation support (CAL3D) 3. Game engine with...Simulation, DES, Simkit, Diskit, Viskit, Savage, XML, Distributed Interactive Simulation, DIS, Blender , X3D Edit 16. PRICE CODE 17. SECURITY...10 5. Blender Authoring Tool

  14. Ground water and energy

    SciTech Connect

    Not Available

    1980-05-01

    In view of complex environmental/energy decisions, the Environmental Impacts Division of the Office of Technology Impacts develops analytical methods for conducting policy analyses supporting decision making. The methods development process often begins with a workshop of leading experts and specialists in the relevant disciplines and issue areas; workshop findings are subsequently utilized by OTI to form a more solid foundation for viable policies. The National Workshop on Ground Water and Energy Production was envisioned as a tool through which OTI could obtain insights, information, and methods (on environmental, economical, physical, political, legal, and social issues) to use in its analyses, models, and assessments. To accomplish this, the Workshop comprised both plenary sessions and individual working groups. The former provided opportunities for all participants to explore issues from a broad perspective, whereas the latter enabled participants to focus on the three following areas: ground water supply; conflicts and barriers to its use; and alternatives or solutions to the various issues. This report summarizes information and insights gained by the Office of Technology Impacts during the course of the Workshop. The Key Findings section summarizes the most important facts discovered during the Workshop. The three general topics that follow (Supply, Conflicts and Barriers, and Alternatives) are those described in the Core Issues statements. The statements are reflective of the recommendations and analyses prepared by the several working groups.

  15. Ground water and climate change

    USDA-ARS?s Scientific Manuscript database

    As the world’s largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food secu¬rity will probably intensify under climate chan...

  16. A geographic data model for representing ground water systems.

    PubMed

    Strassberg, Gil; Maidment, David R; Jones, Norm L

    2007-01-01

    The Arc Hydro ground water data model is a geographic data model for representing spatial and temporal ground water information within a geographic information system (GIS). The data model is a standardized representation of ground water systems within a spatial database that provides a public domain template for GIS users to store, document, and analyze commonly used spatial and temporal ground water data sets. This paper describes the data model framework, a simplified version of the complete ground water data model that includes two-dimensional and three-dimensional (3D) object classes for representing aquifers, wells, and borehole data, and the 3D geospatial context in which these data exist. The framework data model also includes tabular objects for representing temporal information such as water levels and water quality samples that are related with spatial features.

  17. Capturing 3D Water Flow in Rooted Soil by Ultra-fast Neutron Tomography.

    PubMed

    Tötzke, Christian; Kardjilov, Nikolay; Manke, Ingo; Oswald, Sascha E

    2017-07-21

    Water infiltration in soil is not only affected by the inherent heterogeneities of soil, but even more by the interaction with plant roots and their water uptake. Neutron tomography is a unique non-invasive 3D tool to visualize plant root systems together with the soil water distribution in situ. So far, acquisition times in the range of hours have been the major limitation for imaging 3D water dynamics. Implementing an alternative acquisition procedure we boosted the speed of acquisition capturing an entire tomogram within 10 s. This allows, for the first time, tracking of a water front ascending in a rooted soil column upon infiltration of deuterated water time-resolved in 3D. Image quality and resolution could be sustained to a level allowing for capturing the root system in high detail. Good signal-to-noise ratio and contrast were the key to visualize dynamic changes in water content and to localize the root uptake. We demonstrated the ability of ultra-fast tomography to quantitatively image quick changes of water content in the rhizosphere and outlined the value of such imaging data for 3D water uptake modelling. The presented method paves the way for time-resolved studies of various 3D flow and transport phenomena in porous systems.

  18. Ground water: the hidden resource

    USGS Publications Warehouse

    Vandas, Stephen; Farrar, Frank

    1996-01-01

    Ground water is water underground in saturated zones beneath the land surface. Contrary to popular belief, ground water does not form underground "rivers." It fills the pores and fractures in underground materials such as sand, gravel, and other rock. If ground water flows from rock materials or can be removed by pumping from the saturated rock materials In useful amounts, the rock materials are called aquifers. Ground water moves slowly, typically at rates of 7 to 60 centimeters per day in an aquifer. As a result, water could remain in an aquifer for hundreds or thousands of years. Ground water is the source of about 40 percent of water used for public supplies and about 38 percent of water used for agriculture in the United States.

  19. Pedestrian and car detection and classification for unmanned ground vehicle using 3D lidar and monocular camera

    NASA Astrophysics Data System (ADS)

    Cho, Kuk; Baeg, Seung-Ho; Lee, Kimin; Lee, Hae Seok; Park, SangDeok

    2011-05-01

    This paper describes an object detection and classification method for an Unmanned Ground Vehicle (UGV) using a range sensor and an image sensor. The range sensor and the image sensor are a 3D Light Detection And Ranging (LIDAR) sensor and a monocular camera, respectively. For safe driving of the UGV, pedestrians and cars should be detected on their moving routes of the vehicle. An object detection and classification techniques based on only a camera has an inherent problem. On the view point of detection with a camera, a certain algorithm should extract features and compare them with full input image data. The input image has a lot of information as object and environment. It is hard to make a decision of the classification. The image should have only one reliable object information to solve the problem. In this paper, we introduce a developed 3D LIDAR sensor and apply a fusion method both 3D LIDAR data and camera data. We describe a 3D LIDAR sensor which is developed by LG Innotek Consortium in Korea, named KIDAR-B25. The 3D LIDAR sensor detects objects, determines the object's Region of Interest (ROI) based on 3D information and sends it into a camera region for classification. In the 3D LIDAR domain, we recognize breakpoints using Kalman filter and then make a cluster using a line segment method to determine an object's ROI. In the image domain, we extract the object's feature data from the ROI region using a Haar-like feature method. Finally it is classified as a pedestrian or car using a trained database with an Adaboost algorithm. To verify our system, we make an experiment on the performance of our system which is mounted on a ground vehicle, through field tests in an urban area.

  20. 2D and 3D Ground Penetrating Radar monitoring of a reinforced concrete asphalt plate affected by mechanical deformation.

    NASA Astrophysics Data System (ADS)

    Bavusi, M.; Dumoulin, J.; Loperte, A.; Rizzo, E.; Soldovieri, F.

    2012-04-01

    , a zero setting acquisition was carried out before perturbing the plate. Described experience demonstrates the GPR is a reliable technique for the: • foundation soil characterization and monitoring • Reinforced structural elements monitoring • asphalt/reinforced concrete characterization and monitoring • detection of water infiltration, structural elements, defects • evaluation of restoration intervention. In fact, the GPR technique was able to investigate the layers beyond the asphalt and provides a spatial resolution complying with the needs of the technical problem at hand by use of different antennas. Moreover noticeable performances of this technique can be further improved by implementing 3D processing and MT inversion procedures in order to increase the amount of information by the survey [2]. Acknowledgements. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement n. 225663 Joint Call FP7-ICT-SEC-2007-1 [1] Lapenna, V.; Cuomo, V.; Rizzo, E.; Fiore, S.; Troisi, S.; Straface, S. (2006). A new Large Lab-scale Facility for Hydro-Geophysical Experiments: Hydrogeosite. American Geophysical Union, Fall Meeting 2006, abstract #H31B-1422 [2] Bavusi M., Soldovieri F., Di Napoli R., Loperte A., Di Cesare A., Ponzo F.C and Lapenna V. (2011). Ground penetrating radar and microwave tomography 3D applications for the deck evaluation of the Musmeci bridge in Potenza, Italy. J. Geophys. Eng. 8 S33 doi:10.1088/1742-2132/8/3/S04

  1. Comparative studies on gravisensitive protists on ground (2D and 3D clinostats) and in microgravity

    NASA Astrophysics Data System (ADS)

    Hemmersbach, Ruth; Strauch, Sebastian M.; Seibt, Dieter; Schuber, Marianne

    2006-09-01

    In order to prepare and support space experiments, 2D and 3D clinostats are widely applied to study the influence of simulated weightlessness on biological systems. In order to evaluate the results a comparison between the data obtained in simulation experiments and in real microgravity is necessary. We are currently analyzing the gravity-dependent behavior of the protists Paramecium biaurelia (ciliate) and Euglena gracilis (photosynthetic flagellate) on these different experimental platforms. So far, first results are presented concerning the behaviour of Euglena on a 2D fast rotating clinostat and a 3D clinostat as well as under real microgravity conditions (TEXUS sounding rocket flight), of Paramecium on a 2D clinostat and in microgravity. Our data show similar results during 2D and 3D clinorotation compared to real microgravity with respect to loss of orientation (gravitaxis) of Paramecium and Euglena and a decrease of linearity of the cell tracks of Euglena. However, the increase of the mean swimming velocities, especially during 3D clinorotation (Euglena) and 2D clinorotation of Paramecium might indicate a persisting mechanostimulation of the cells. Further studies including long-term 2D and 3D clinostat exposition will enable us to demonstrate the qualification of the applied simulation methods.

  2. High-performance 3D printing of hydrogels by water-dispersible photoinitiator nanoparticles.

    PubMed

    Pawar, Amol A; Saada, Gabriel; Cooperstein, Ido; Larush, Liraz; Jackman, Joshua A; Tabaei, Seyed R; Cho, Nam-Joon; Magdassi, Shlomo

    2016-04-01

    In the absence of water-soluble photoinitiators with high absorbance in the ultraviolet (UV)-visible range, rapid three-dimensional (3D) printing of hydrogels for tissue engineering is challenging. A new approach enabling rapid 3D printing of hydrogels in aqueous solutions is presented on the basis of UV-curable inks containing nanoparticles of highly efficient but water-insoluble photoinitiators. The extinction coefficient of the new water-dispersible nanoparticles of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) is more than 300 times larger than the best and most used commercially available water-soluble photoinitiator. The TPO nanoparticles absorb significantly in the range from 385 to 420 nm, making them suitable for use in commercially available, low-cost, light-emitting diode-based 3D printers using digital light processing. The polymerization rate at this range is very fast and enables 3D printing that otherwise is impossible to perform without adding solvents. The TPO nanoparticles were prepared by rapid conversion of volatile microemulsions into water-dispersible powder, a process that can be used for a variety of photoinitiators. Such water-dispersible photoinitiator nanoparticles open many opportunities to enable rapid 3D printing of structures prepared in aqueous solutions while bringing environmental advantages by using low-energy curing systems and avoiding the need for solvents.

  3. High-performance 3D printing of hydrogels by water-dispersible photoinitiator nanoparticles

    PubMed Central

    Pawar, Amol A.; Saada, Gabriel; Cooperstein, Ido; Larush, Liraz; Jackman, Joshua A.; Tabaei, Seyed R.; Cho, Nam-Joon; Magdassi, Shlomo

    2016-01-01

    In the absence of water-soluble photoinitiators with high absorbance in the ultraviolet (UV)–visible range, rapid three-dimensional (3D) printing of hydrogels for tissue engineering is challenging. A new approach enabling rapid 3D printing of hydrogels in aqueous solutions is presented on the basis of UV-curable inks containing nanoparticles of highly efficient but water-insoluble photoinitiators. The extinction coefficient of the new water-dispersible nanoparticles of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) is more than 300 times larger than the best and most used commercially available water-soluble photoinitiator. The TPO nanoparticles absorb significantly in the range from 385 to 420 nm, making them suitable for use in commercially available, low-cost, light-emitting diode–based 3D printers using digital light processing. The polymerization rate at this range is very fast and enables 3D printing that otherwise is impossible to perform without adding solvents. The TPO nanoparticles were prepared by rapid conversion of volatile microemulsions into water-dispersible powder, a process that can be used for a variety of photoinitiators. Such water-dispersible photoinitiator nanoparticles open many opportunities to enable rapid 3D printing of structures prepared in aqueous solutions while bringing environmental advantages by using low-energy curing systems and avoiding the need for solvents. PMID:27051877

  4. Estimating 3D variation in active-layer thickness beneath arctic streams using ground-penetrating radar

    USGS Publications Warehouse

    Brosten, T.R.; Bradford, J.H.; McNamara, J.P.; Gooseff, M.N.; Zarnetske, J.P.; Bowden, W.B.; Johnston, M.E.

    2009-01-01

    We acquired three-dimensional (3D) ground-penetrating radar (GPR) data across three stream sites on the North Slope, AK, in August 2005, to investigate the dependence of thaw depth on channel morphology. Data were migrated with mean velocities derived from multi-offset GPR profiles collected across a stream section within each of the 3D survey areas. GPR data interpretations from the alluvial-lined stream site illustrate greater thaw depths beneath riffle and gravel bar features relative to neighboring pool features. The peat-lined stream sites indicate the opposite; greater thaw depths beneath pools and shallower thaw beneath the connecting runs. Results provide detailed 3D geometry of active-layer thaw depths that can support hydrological studies seeking to quantify transport and biogeochemical processes that occur within the hyporheic zone.

  5. SUPERFUND GROUND WATER ISSUE: GROUND WATER SAMPLING FOR METALS ANALYSES

    EPA Science Inventory

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Syperfund cleanup pracices occurs where one EPA Region implements a remedial action based on unfiltered ground-water samples,...

  6. SUPERFUND GROUND WATER ISSUE: GROUND WATER SAMPLING FOR METALS ANALYSES

    EPA Science Inventory

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Syperfund cleanup pracices occurs where one EPA Region implements a remedial action based on unfiltered ground-water samples,...

  7. 3D reconstruction from a monocular vision system for unmanned ground vehicles

    NASA Astrophysics Data System (ADS)

    Tompkins, R. Cortland; Diskin, Yakov; Youssef, Menatoallah M.; Asari, Vijayan K.

    2011-11-01

    In this paper we present a 3D reconstruction technique designed to support an autonomously navigated unmanned system. The algorithm and methods presented focus on the 3D reconstruction of a scene, with color and distance information, using only a single moving camera. In this way, the system may provide positional self-awareness for navigation within a known, GPS-denied area. It can also be used to construct a new model of unknown areas. Existing 3D reconstruction methods for GPS-denied areas often rely on expensive inertial measurement units to establish camera location and orientation. The algorithm proposed---after the preprocessing tasks of stabilization and video enhancement---performs Speeded-Up Robust Feature extraction, in which we locate unique stable points within every frame. Additional features are extracted using an optical flow method, with the resultant points fused and pruned based on several quality metrics. Each unique point is then tracked through the video sequence and assigned a disparity value used to compute the depth for each feature within the scene. The algorithm also assigns each feature point a horizontal and vertical coordinate using the camera's field of views specifications. From this, a resultant point cloud consists of thousands of feature points plotted from a particular camera position and direction, generated from pairs of sequential frames. The proposed method can use the yaw, pitch and roll information calculated from visual cues within the image data to accurately compute location and orientation. This positioning information enables the reconstruction of a robust 3D model particularly suitable for autonomous navigation and mapping tasks.

  8. Template-Free Synthesis of Functional 3D BN architecture for removal of dyes from water

    NASA Astrophysics Data System (ADS)

    Liu, Dan; Lei, Weiwei; Qin, Si; Chen, Ying

    2014-03-01

    Three-dimensional (3D) architectures are of interest in applications in electronics, catalysis devices, sensors and adsorption materials. However, it is still a challenge to fabricate 3D BN architectures by a simple method. Here, we report the direct synthesis of 3D BN architectures by a simple thermal treatment process. A 3D BN architecture consists of an interconnected flexible network of nanosheets. The typical nitrogen adsorption/desorption results demonstrate that the specific surface area for the as-prepared samples is up to 1156 m2 g-1, and the total pore volume is about 1.17 cm3 g-1. The 3D BN architecture displays very high adsorption rates and large capacities for organic dyes in water without any other additives due to its low densities, high resistance to oxidation, good chemical inertness and high surface area. Importantly, 88% of the starting adsorption capacity is maintained after 15 cycles. These results indicate that the 3D BN architecture is potential environmental materials for water purification and treatment.

  9. Ground water and climate change

    USGS Publications Warehouse

    Taylor, Richard G.; Scanlon, Bridget; Döll, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F.P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2012-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  10. Ground water and climate change

    NASA Astrophysics Data System (ADS)

    Taylor, Richard G.; Scanlon, Bridget; Döll, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F. P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2013-04-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  11. Ground Water and Climate Change

    NASA Technical Reports Server (NTRS)

    Taylor, Richard G.; Scanlon, Bridget; Doell, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; hide

    2013-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  12. Sedimentary basin effects in Seattle, Washington: Ground-motion observations and 3D simulations

    USGS Publications Warehouse

    Frankel, Arthur; Stephenson, William; Carver, David

    2009-01-01

    Seismograms of local earthquakes recorded in Seattle exhibit surface waves in the Seattle basin and basin-edge focusing of S waves. Spectral ratios of Swaves and later arrivals at 1 Hz for stiff-soil sites in the Seattle basin show a dependence on the direction to the earthquake, with earthquakes to the south and southwest producing higher average amplification. Earthquakes to the southwest typically produce larger basin surface waves relative to S waves than earthquakes to the north and northwest, probably because of the velocity contrast across the Seattle fault along the southern margin of the Seattle basin. S to P conversions are observed for some events and are likely converted at the bottom of the Seattle basin. We model five earthquakes, including the M 6.8 Nisqually earthquake, using 3D finite-difference simulations accurate up to 1 Hz. The simulations reproduce the observed dependence of amplification on the direction to the earthquake. The simulations generally match the timing and character of basin surface waves observed for many events. The 3D simulation for the Nisqually earth-quake produces focusing of S waves along the southern margin of the Seattle basin near the area in west Seattle that experienced increased chimney damage from the earthquake, similar to the results of the higher-frequency 2D simulation reported by Stephenson et al. (2006). Waveforms from the 3D simulations show reasonable agreement with the data at low frequencies (0.2-0.4 Hz) for the Nisqually earthquake and an M 4.8 deep earthquake west of Seattle.

  13. Intergrated 3-D Ground-Penetrating Radar,Outcrop,and Boreholoe Data Applied to Reservoir Characterization and Flow Simulation.

    SciTech Connect

    McMechan et al.

    2001-08-31

    Existing reservoir models are based on 2-D outcrop;3-D aspects are inferred from correlation between wells,and so are inadequately constrained for reservoir simulations. To overcome these deficiencies, we initiated a multidimensional characterization of reservoir analogs in the Cretaceous Ferron Sandstone in Utah.The study was conducted at two sites(Corbula Gulch Coyote Basin); results from both sites are contained in this report. Detailed sedimentary facies maps of cliff faces define the geometry and distribution of potential reservoir flow units, barriers and baffles at the outcrop. High resolution 2-D and 3-D ground penetrating radar(GPR) images extend these reservoir characteristics into 3-D to allow development of realistic 3-D reservoir models. Models use geometric information from the mapping and the GPR data, petrophysical data from surface and cliff-face outcrops, lab analyses of outcrop and core samples, and petrography. The measurements are all integrated into a single coordinate system using GPS and laser mapping of the main sedimentologic features and boundaries. The final step is analysis of results of 3-D fluid flow modeling to demonstrate applicability of our reservoir analog studies to well siting and reservoir engineering for maximization of hydrocarbon production. The main goals of this project are achieved. These are the construction of a deterministic 3-D reservoir analog model from a variety of geophysical and geologic measurements at the field sites, integrating these into comprehensive petrophysical models, and flow simulation through these models. This unique approach represents a significant advance in characterization and use of reservoir analogs. To data,the team has presented five papers at GSA and AAPG meetings produced a technical manual, and completed 15 technical papers. The latter are the main content of this final report. In addition,the project became part of 5 PhD dissertations, 3 MS theses,and two senior undergraduate research

  14. Integrated 3-D Ground-Penetrating Radar, Outcrop, and Borehole Data Applied to Reservoir Characterization and Flow Simulation

    SciTech Connect

    George McMechan; Rucsandra Corbeanu; Craig Forster; Kristian Soegaard; Xiaoxian Zeng; Carlos Aiken; Robert Szerbiak; Janok Bhattacharya; Michael Wizevich; Xueming Xu; Stephen Snelgrove; Karen Roche; Siang Joo Lim; Djuro Navakovic; Christopher White; Laura Crossey; Deming Wang; John Thurmond; William Hammon III; Mamadou BAlde; Ari Menitove

    2001-08-31

    OAK-B135 (IPLD Cleared) Existing reservoir models are based on 2-D outcrop studies; 3-D aspects are inferred from correlation between wells, and so are inadequately constrained for reservoir simulations. To overcome these deficiencies, we initiated a multidimensional characterization of reservoir analogs in the Cretaceous Ferron Sandstone in Utah. The study was conducted at two sites (Corbula Gulch and Coyote Basin); results from both sites are contained in this report. Detailed sedimentary facies maps of cliff faces define the geometry and distribution of potential reservoir flow units, barriers and baffles at the outcrop. High resolution 2-D and 3-D ground-penetrating radar (GPR) images extend these reservoir characteristics into 3-D, to allow development of realistic 3-D reservoir models. Models use geometric information from the mapping and the GPR data, petrophysical data from surface and cliff-face outcrops, lab analyses of outcrop and core samples, and petrography. The measurements are all integrated into a single coordinate system using GPS and laser mapping of the main sedimentological features and boundaries.The final step is analysis of results of 3-D fluid flow modeling to demonstrate applicability of our reservoir analog studies to well siting and reservoir engineering for maximization of hydrocarbon production. The main goals of the project are achieved. These are the construction of a deterministic 3-D reservoir analog model from a variety of geophysical and geologic measurements at the field sites, integrating these into comprehensive petrophysical models, and flow simulations through these models. This unique approach represents a significant advance in characterization and use of reservoir analogs.

  15. Inclusion of high resolution MODIS maps on a 3D tropospheric water vapor GPS tomography model

    NASA Astrophysics Data System (ADS)

    Benevides, Pedro; Catalao, Joao; Nico, Giovanni; Miranda, Pedro M. A.

    2015-10-01

    Observing the water vapor distribution on the troposphere remains a challenge for the weather forecast. Radiosondes provide precise water vapor profiles of the troposphere, but lack geographical and temporal coverage, while satellite meteorological maps have good spatial resolution but even poorer temporal resolution. GPS has proved its capacity to measure the integrated water vapor in all weather conditions with high temporal sampling frequency. However these measurements lack a vertical water vapor discretization. Reconstruction of the slant path GPS observation to the satellite allows oblique water vapor measurements. Implementation of a 3D grid of voxels along the troposphere over an area where GPS stations are available enables the observation ray tracing. A relation between the water vapor density and the distanced traveled inside the voxels is established, defining GPS tomography. An inverse problem formulation is needed to obtain a water vapor solution. The combination of precipitable water vapor (PWV) maps obtained from MODIS satellite data with the GPS tomography is performed in this work. The MODIS PWV maps can have 1 or 5 km pixel resolution, being obtained 2 times per day in the same location at most. The inclusion of MODIS PWV maps provides an enhanced horizontal resolution for the tomographic solution and benefits the stability of the inversion problem. A 3D tomographic grid was adjusted over a regional area covering Lisbon, Portugal, where a GNSS network of 9 receivers is available. Radiosonde measurements in the area are used to evaluate the 3D water vapor tomography maps.

  16. 3D time dependent thermo-fluid dynamic model of ground deformation at Campi Flegrei caldera

    NASA Astrophysics Data System (ADS)

    Castaldo, R.; Tizzani, P.; Manconi, A.; Manzo, M.; Pepe, S.; Pepe, A.; Lanari, R.

    2012-04-01

    In active volcanic areas deformation signals are generally characterized by non-linear spatial and temporal variations [Tizzani P. et al., 2007]. This behaviour has been revealed in the last two decades by the so-called advanced DInSAR processing algorithms, developed to analyze surface deformation phenomena [Berardino P. et al., 2002; Ferretti C. et al., 2001]. Notwithstanding, most of the inverse modelling attempts to characterize the evolution of the volcanic sources are based on the assumption that the Earth's crust behaves as a homogeneous linear elastic material. However, the behaviour of the upper lithosphere in thermally anomalous regions (as active volcanoes are) might be well described as a non-Newtonian fluid, where some of the material proprieties of the rocks (i.e., apparent viscosities) can change over time [Pinkerton H. et al., 1995]. In this context, we considered the thermal proprieties and mechanical heterogeneities of the upper crust in order to develop a new 3D time dependent thermo-fluid dynamic model of Campi Flegrei (CF) caldera, Southern Italy. More specifically, according to Tizzani P. et al. (2010), we integrated in a FEM environment geophysical information (gravimetric, seismic, and borehole data) available for the considered area and performed two FEM optimization procedures to constrain the 3D distribution of unknown physical parameters (temperature and viscosity distributions) that might help explaining the data observed at surface (geothermal wells and DInSAR measurements). First, we searched for the heat production, the volume source distribution and surface emissivity parameters providing the best-fit of the geothermal profiles data measured at six boreholes [Agip ESGE, 1986], by solving the Fourier heat equation over time (about 40 kys). The 3D thermal field resulting from this optimization was used to calculate the 3D brittle-ductile transition. This analysis revealed the presence of a ductile region, located beneath the centre of

  17. Comparison of INSAT-3D AOD over Indian region with satellite- and ground-based measurements: a data assimilation perspective

    NASA Astrophysics Data System (ADS)

    Kumar, Sumit; George, John P.; Sreevathsa, M. N. Raghavendra; Indira Rani, S.

    2016-05-01

    This paper aims at comparing the INSAT-3D AOD with other space based observations over the continental regions. INSAT-3D launched in 2013 is an advanced geostationary weather satellite of India at 82° East longitude provides Aerosol Optical Depth (AOD) observations at 650 nm over both land and ocean. The level-3 daily AOD measurements from MODIS (both Aqua and Terra) and MISR are used for comparison with that from INSAT-3D. This work is applied during premonsoon season of 2015. Overall statistical scores and systematic errors are compared to characterize various error sources. Our study indicates that significant differences exist between different aerosol observations which may be partly due to retrieval algorithm, sensor configurations and temporal sampling. Comparison of INSAT observed AOD shows less bias towards MISR and MODIS-Terra observed AOD than with MODIS-Aqua. The INSAT observations over oceanic region have better correlation, minimum bias and rmse than land region. Overall, the mean bias of the dataset is ±0.05, with a root mean square error of 0.22, but these errors are also found highly dependent on geographical region. Additionally, we compared INSAT 660 nm AOD with two AERONET ground stations. The comparison of INSAT with different observations shows that the retrieved AOD is closer to the ground-based data than the MISR and MODIS AOD.

  18. Application of 3D electrical capacitance tomography in probing anomalous blocks in water

    NASA Astrophysics Data System (ADS)

    Liao, Aimin; Zhou, Qiyou; Zhang, Yun

    2015-06-01

    Water usually acts as a high-permittivity dielectric in many fields such as geophysics, hydrology, hydrogeology, aquaculture, etc. Thus, it may be of significance to adapt ECT to the fields with a high permittivity in which the conventional ECT is scarcely involved. To achieve this objective, a simplified 3D-ECT system was constructed with a high-precision inductance capacitance resistance meter and programmable logic controllers. In the aspect of sensing unit of the system, two geometries (i.e. cylinder and cube) of 3D sensors were constructed to probe anomalous blocks in water. Numerical simulations and physical experiments for both the sensors were performed to test the effectiveness of the constructed system to probe anomalous blocks in water. Furthermore, to justify the availability of this system in some possible fields, two experiments associated with applications of the 3D-ECT system were performed to measure the distribution of a plant root system in water, and to monitor the infiltration of water in soil in field. The experimental results demonstrate that the ECT system is capable of probing the location and rough size of anomalous blocks in water with both the sensors, determining the distribution of a plant root system in water, and monitoring the infiltration process of water in soil.

  19. Examination about Influence for Precision of 3d Image Measurement from the Ground Control Point Measurement and Surface Matching

    NASA Astrophysics Data System (ADS)

    Anai, T.; Kochi, N.; Yamada, M.; Sasaki, T.; Otani, H.; Sasaki, D.; Nishimura, S.; Kimoto, K.; Yasui, N.

    2015-05-01

    As the 3D image measurement software is now widely used with the recent development of computer-vision technology, the 3D measurement from the image is now has acquired the application field from desktop objects as wide as the topography survey in large geographical areas. Especially, the orientation, which used to be a complicated process in the heretofore image measurement, can be now performed automatically by simply taking many pictures around the object. And in the case of fully textured object, the 3D measurement of surface features is now done all automatically from the orientated images, and greatly facilitated the acquisition of the dense 3D point cloud from images with high precision. With all this development in the background, in the case of small and the middle size objects, we are now furnishing the all-around 3D measurement by a single digital camera sold on the market. And we have also developed the technology of the topographical measurement with the air-borne images taken by a small UAV [1~5]. In this present study, in the case of the small size objects, we examine the accuracy of surface measurement (Matching) by the data of the experiments. And as to the topographic measurement, we examine the influence of GCP distribution on the accuracy by the data of the experiments. Besides, we examined the difference of the analytical results in each of the 3D image measurement software. This document reviews the processing flow of orientation and the 3D measurement of each software and explains the feature of the each software. And as to the verification of the precision of stereo-matching, we measured the test plane and the test sphere of the known form and assessed the result. As to the topography measurement, we used the air-borne image data photographed at the test field in Yadorigi of Matsuda City, Kanagawa Prefecture JAPAN. We have constructed Ground Control Point which measured by RTK-GPS and Total Station. And we show the results of analysis made

  20. A neural network based 3D/3D image registration quality evaluator for the head-and-neck patient setup in the absence of a ground truth

    SciTech Connect

    Wu Jian; Murphy, Martin J.

    2010-11-15

    Purpose: To develop a neural network based registration quality evaluator (RQE) that can identify unsuccessful 3D/3D image registrations for the head-and-neck patient setup in radiotherapy. Methods: A two-layer feed-forward neural network was used as a RQE to classify 3D/3D rigid registration solutions as successful or unsuccessful based on the features of the similarity surface near the point-of-solution. The supervised training and test data sets were generated by rigidly registering daily cone-beam CTs to the treatment planning fan-beam CTs of six patients with head-and-neck tumors. Two different similarity metrics (mutual information and mean-squared intensity difference) and two different types of image content (entire image versus bony landmarks) were used. The best solution for each registration pair was selected from 50 optimizing attempts that differed only by the initial transformation parameters. The distance from each individual solution to the best solution in the normalized parametrical space was compared to a user-defined error threshold to determine whether that solution was successful or not. The supervised training was then used to train the RQE. The performance of the RQE was evaluated using the test data set that consisted of registration results that were not used in training. Results: The RQE constructed using the mutual information had very good performance when tested using the test data sets, yielding the sensitivity, the specificity, the positive predictive value, and the negative predictive value in the ranges of 0.960-1.000, 0.993-1.000, 0.983-1.000, and 0.909-1.000, respectively. Adding a RQE into a conventional 3D/3D image registration system incurs only about 10%-20% increase of the overall processing time. Conclusions: The authors' patient study has demonstrated very good performance of the proposed RQE when used with the mutual information in identifying unsuccessful 3D/3D registrations for daily patient setup. The classifier had

  1. Transparent 3D Visualization of Archaeological Remains in Roman Site in Ankara-Turkey with Ground Penetrating Radar Method

    NASA Astrophysics Data System (ADS)

    Kadioglu, S.

    2009-04-01

    Transparent 3D Visualization of Archaeological Remains in Roman Site in Ankara-Turkey with Ground Penetrating Radar Method Selma KADIOGLU Ankara University, Faculty of Engineering, Department of Geophysical Engineering, 06100 Tandogan/ANKARA-TURKEY kadioglu@eng.ankara.edu.tr Anatolia has always been more the point of transit, a bridge between West and East. Anatolia has been a home for ideas moving from all directions. So it is that in the Roman and post-Roman periods the role of Anatolia in general and of Ancyra (the Roman name of Ankara) in particular was of the greatest importance. Now, the visible archaeological remains of Roman period in Ankara are Roman Bath, Gymnasium, the Temple of Augustus of Rome, Street, Theatre, City Defence-Wall. The Caesar Augustus, the first Roman Emperor, conquered Asia Minor in 25 BC. Then a marble temple was built in Ancyra, the administrative capital of province, today the capital of Turkish Republic, Ankara. This monument was consecrated to the Empreror and to the Goddess Rome. This temple is supposed to have built over an earlier temple dedicated to Kybele and Men between 25 -20 BC. After the death of the Augustus in 14AD, a copy of the text of "Res Gestae Divi Augusti" was inscribed on the interior of the pronaos in Latin, whereas a Greek translation is also present on an exterior wall of the cella. In the 5th century, it was converted in to a church by the Byzantines. The aim of this study is to determine old buried archaeological remains in the Augustus temple, Roman Bath and in the governorship agora in Ulus district. These remains were imaged with transparent three dimensional (3D) visualization of the ground penetrating radar (GPR) data. Parallel two dimensional (2D) GPR profile data were acquired in the study areas, and then a 3D data volume were built using parallel 2D GPR data. A simplified amplitude-colour range and appropriate opacity function were constructed and transparent 3D image were obtained to activate buried

  2. Supply-demand 3D dynamic model in water resources evaluation: taking Lebanon as an example

    NASA Astrophysics Data System (ADS)

    Fang, Hong; Hou, Zhimin

    2017-05-01

    In this paper, supply-demand 3D dynamic model is adopted to create a measurement of a region’s capacity to provide available water to meet the needs of its population. First of all, we draw a diagram between supply and demand. Then taking the main dynamic factors into account, we establish an index to evaluate the balance of supply and demand. The three dimension vector reflects the scarcity of industrial, agricultural and residential water. Lebanon is chosen as the object of case study, and we do quantitative analysis of its current situation. After data collecting and processing, we calculate the 3D vector in 2012, which reveals that agriculture is susceptible to water scarcity. Water resources of Lebanon are “physical rich” but “economic scarcity” according to the correlation chart and other statistical analysis.

  3. 3-D Sound Propagation and Acoustic Inversions in Shallow Water Oceans

    DTIC Science & Technology

    2011-09-01

    method is used to study canonical environmental models of shelfbreak front systems and nonlinear internal wave ducts. The WHOI 3D Parabolic-Equation...localization methods with normal mode theory have been established for localizing low frequency, broadband signals in a shallow water environment. Gauss ...approach for low-frequency broadband sound source localization in a shallow-water ocean is established. Gauss -Markov inverse theory is used in both

  4. Real-time forecasting of Hong Kong beach water quality by 3D deterministic model.

    PubMed

    Chan, S N; Thoe, W; Lee, J H W

    2013-03-15

    Bacterial level (e.g. Escherichia coli) is generally adopted as the key indicator of beach water quality due to its high correlation with swimming associated illnesses. A 3D deterministic hydrodynamic model is developed to provide daily water quality forecasting for eight marine beaches in Tsuen Wan, which are only about 8 km from the Harbour Area Treatment Scheme (HATS) outfall discharging 1.4 million m(3)/d of partially-treated sewage. The fate and transport of the HATS effluent and its impact on the E. coli level at nearby beaches are studied. The model features the seamless coupling of near field jet mixing and the far field transport and dispersion of wastewater discharge from submarine outfalls, and a spatial-temporal dependent E. coli decay rate formulation specifically developed for sub-tropical Hong Kong waters. The model prediction of beach water quality has been extensively validated against field data both before and after disinfection of the HATS effluent. Compared with daily beach E. coli data during August-November 2011, the model achieves an overall accuracy of 81-91% in forecasting compliance/exceedance of beach water quality standard. The 3D deterministic model has been most valuable in the interpretation of the complex variation of beach water quality which depends on tidal level, solar radiation and other hydro-meteorological factors. The model can also be used in optimization of disinfection dosage and in emergency response situations.

  5. Nanostructured materials on 3D nickel foam as electrocatalysts for water splitting.

    PubMed

    Chaudhari, Nitin K; Jin, Haneul; Kim, Byeongyoon; Lee, Kwangyeol

    2017-08-31

    Highly efficient and low-cost electrocatalysts are essential for water spitting via electrolysis in an economically viable fashion. However, the best catalytic performance is found with noble metal-based electrocatalysts, which presents a formidable obstacle for the commercial success of electrolytic water splitting-based H2 production due to their relatively high cost and scarcity. Therefore, the development of alternative inexpensive earth-abundant electrode materials with excellent electrocatalytic properties is of great urgency. In general, efficient electrocatalysts must possess several key characteristics such as low overpotential, good electrocatalytic activity, high stability, and low production costs. Direct synthesis of nanostructured catalysts on a conducting substrate may potentially improve the performance of the resultant electrocatalysts because of their high catalytic surface areas and the synergistic effect between the electrocatalyst and the conductive substrate. In this regard, three dimensional (3D) nickel foams have been advantageously utilized as electrode substrates as they offer a large active surface area and a highly conductive continuous porous 3D network. In this review, we discuss the most recent developments in nanostructured materials directly synthesized on 3D nickel foam as potential electrode candidates for electrochemical water electrolysis, namely, the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). We also provide perspectives and outlooks for catalysts grown directly on 3D conducting substrates for future sustainable energy technologies.

  6. Natural Radionuclides in Ground Water.

    ERIC Educational Resources Information Center

    Davis, Stanley N.

    1988-01-01

    Described are the natural trace radionuclides in ground water. Indicates the geologic origin of these radionuclides. Discusses the importance of these radionuclides. Suggests future uses of a number of additional radionuclides. (CW)

  7. Natural Radionuclides in Ground Water.

    ERIC Educational Resources Information Center

    Davis, Stanley N.

    1988-01-01

    Described are the natural trace radionuclides in ground water. Indicates the geologic origin of these radionuclides. Discusses the importance of these radionuclides. Suggests future uses of a number of additional radionuclides. (CW)

  8. Ground water investigations in Oklahoma

    USGS Publications Warehouse

    Davis, Leon V.

    1955-01-01

    Prior to 1937, ground-water work in Oklahoma consisted of broad scale early-day reconnaissance and a few brief investigations of local areas. The reconnaissance is distinguished by C. N. Gould's "Geology and Water Resources of Oklahoma" (Water-Supply Paper 148, 1905), which covers about half of the present State of Oklahoma. Among the shorter reports are two by Schwennesen for areas near Enid and Oklahoma City, one by Renick for Enid, and one by Thompson on irrigation possibilities near Gage. These reports are now inadequate by modern standards.Cooperative ground-water work in Oklahoma by the United States Geological Survey began in 1937, with the Oklahoma Geological Survey as cooperating agency. With the passage of the new ground-water law by the State Legislature in 1949, the need for more information on available ground waters and the safe yield of the various aquifers became very pressing. Accordingly, the Division of Water Resources of the Oklahoma Planning and Resources Board, to which was delegated the responsibility of administering the Ground-Water Law, entered into a cooperative agreement with the U.S. Geological Survey, providing for an expansion of ground-water investigations. Both cooperators have consistently given full and enthusiastic cooperation, often beyond the requirements of the cooperative program.The first cooperative investigation was an evaluation of ground-water supplies available for irrigation in the Panhandle. In 1937 the Panhandle was still very much in the dust bowl, and it was hoped that irrigation would alleviate the drought. A bulletin on Texas County was published in 1939, and one on Cimarron County in 1943. Ground-water investigations during the World War II were restricted to the demands of Army and Navy installations, and to defense industries. Ground-water investigations since 1945 have included both country-wide and aquifer-type investigations. In Oklahoma it has been the policy for the State cooperator to publish the results

  9. Ground motion in the presence of complex Topography II: Earthquake sources and 3D simulations

    USGS Publications Warehouse

    Hartzell, Stephen; Ramirez-Guzman, Leonardo; Meremonte, Mark; Leeds, Alena L.

    2017-01-01

    Eight seismic stations were placed in a linear array with a topographic relief of 222 m over Mission Peak in the east San Francisco Bay region for a period of one year to study topographic effects. Seventy‐two well‐recorded local earthquakes are used to calculate spectral amplitude ratios relative to a reference site. A well‐defined fundamental resonance peak is observed with individual station amplitudes following the theoretically predicted progression of larger amplitudes in the upslope direction. Favored directions of vibration are also seen that are related to the trapping of shear waves within the primary ridge dimensions. Spectral peaks above the fundamental one are also related to topographic effects but follow a more complex pattern. Theoretical predictions using a 3D velocity model and accurate topography reproduce many of the general frequency and time‐domain features of the data. Shifts in spectral frequencies and amplitude differences, however, are related to deficiencies of the model and point out the importance of contributing factors, including the shear‐wave velocity under the topographic feature, near‐surface velocity gradients, and source parameters.

  10. Effects of 3-D Visualization of Groundwater Modeling for Water Resource Decision Making

    NASA Astrophysics Data System (ADS)

    Block, J. L.; Arrowsmith, R.

    2006-12-01

    The rise of 3-D visualization hardware and software technology provides important opportunities to advance scientific and policy research. Although the petroleum industry has used immersive 3-D technology since the early 1990's for the visualization of geologic data among experts, there has been little use of this technology for decision making. The Decision Theater at ASU is a new facility using immersive visualization technology designed to combine scientific research at the university with policy decision making in the community. I document a case study in the use of 3-D immersive technology for water resource management in Arizona. Since the turn of the 20th century, natural hydrologic processes in the greater Phoenix region (Salt River Valley) have been shut down via the construction of dams, canals, wells, water treatment plants, and recharge facilities. Water from rivers that once naturally recharged the groundwater aquifer have thus been diverted while continuing groundwater outflow from wells has drawn the aquifer down hundreds of feet. MODFLOW is used to simulate groundwater response to the different water management decisions which impact the artificial and natural inflow and outflow. The East Valley Water Forum, a partnership of water providers east of Phoenix, used the 3-D capabilities of the Decision Theater to build visualizations of the East Salt River Valley groundwater system based on MODFLOW outputs to aid the design of a regional groundwater management plan. The resulting visualizations are now being integrated into policy decisions about long term water management. I address challenges in visualizing scientific information for policy making and highlight the roles of policy actors, specifically geologists, computer scientists, and political decision makers, involved in designing the visualizations. The results show that policy actors respond differently to the 3-D visualization techniques based on their experience, background, and objectives

  11. Predicting ground geoelectric field using magnetospheric model and 3d conductivity model of Earth

    NASA Astrophysics Data System (ADS)

    Honkonen, I. J.; Kuvshinov, A. V.; Rastaetter, L.; Pulkkinen, A. A.

    2016-12-01

    We present a numerical scheme for modeling the effect of space weather on ground geoelectric field which takes into account the 3-dimensional distribution of Earth's conductivity. The scheme involves two steps: 1) Using a magnetohydrodynamic model of the magnetosphere coupled to an electrostatic model of the ionosphere, we compute the external magnetic field source (in the form of equivalent currents) that is responsible for a specific geomagnetic disturbance. 2) Solving the induction equations for a given source from step 1 and given 3-dimensional conductivity model of the Earth. We implement a scheme to compute geoelectric and magnetic fields during Halloween storm (2003-10-29) and discuss the results.

  12. Laser nanostructuring 3-D bioconstruction based on carbon nanotubes in a water matrix of albumin

    NASA Astrophysics Data System (ADS)

    Gerasimenko, Alexander Y.; Ichkitidze, Levan P.; Podgaetsky, Vitaly M.; Savelyev, Mikhail S.; Selishchev, Sergey V.

    2016-04-01

    3-D bioconstructions were created using the evaporation method of the water-albumin solution with carbon nanotubes (CNTs) by the continuous and pulsed femtosecond laser radiation. It is determined that the volume structure of the samples created by the femtosecond radiation has more cavities than the one created by the continuous radiation. The average diameter for multi-walled carbon nanotubes (MWCNTs) samples was almost two times higher (35-40 nm) than for single-walled carbon nanotubes (SWCNTs) samples (20-30 nm). The most homogenous 3-D bioconstruction was formed from MWCNTs by the continuous laser radiation. The hardness of such samples totaled up to 370 MPa at the nanoscale. High strength properties and the resistance of the 3-D bioconstructions produced by the laser irradiation depend on the volume nanotubes scaffold forming inside them. The scaffold was formed by the electric field of the directed laser irradiation. The covalent bond energy between the nanotube carbon molecule and the oxygen of the bovine serum albumin aminoacid residue amounts 580 kJ/mol. The 3-D bioconstructions based on MWCNTs and SWCNTs becomes overgrown with the cells (fibroblasts) over the course of 72 hours. The samples based on the both types of CNTs are not toxic for the cells and don't change its normal composition and structure. Thus the 3-D bioconstructions that are nanostructured by the pulsed and continuous laser radiation can be applied as implant materials for the recovery of the connecting tissues of the living body.

  13. Modeled ground water age distributions

    USGS Publications Warehouse

    Woolfenden, Linda R.; Ginn, Timothy R.

    2009-01-01

    The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from different recharge sources to aquifers. A numerical solution of the ground water age equation of Ginn (1999) was tested both on a hypothetical simplified one-dimensional flow system and under real world conditions. Results from these simulations yield the first continuous distributions of ground water age using this model. Complete age distributions as a function of one and two space dimensions were obtained from both numerical experiments. Simulations in the test problem produced mean ages that were consistent with the expected value at the end of the model domain for all dispersivity values tested, although the mean ages for the two highest dispersivity values deviated slightly from the expected value. Mean ages in the dispersionless case also were consistent with the expected mean ages throughout the physical model domain. Simulations under real world conditions for three dispersivity values resulted in decreasing mean age with increasing dispersivity. This likely is a consequence of an edge effect. However, simulations for all three dispersivity values tested were mass balanced and stable demonstrating that the solution of the ground water age equation can provide estimates of water mass density distributions over age under real world conditions.

  14. Modeled ground water age distributions.

    PubMed

    Woolfenden, Linda R; Ginn, Timothy R

    2009-01-01

    The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from different recharge sources to aquifers. A numerical solution of the ground water age equation of Ginn (1999) was tested both on a hypothetical simplified one-dimensional flow system and under real world conditions. Results from these simulations yield the first continuous distributions of ground water age using this model. Complete age distributions as a function of one and two space dimensions were obtained from both numerical experiments. Simulations in the test problem produced mean ages that were consistent with the expected value at the end of the model domain for all dispersivity values tested, although the mean ages for the two highest dispersivity values deviated slightly from the expected value. Mean ages in the dispersionless case also were consistent with the expected mean ages throughout the physical model domain. Simulations under real world conditions for three dispersivity values resulted in decreasing mean age with increasing dispersivity. This likely is a consequence of an edge effect. However, simulations for all three dispersivity values tested were mass balanced and stable demonstrating that the solution of the ground water age equation can provide estimates of water mass density distributions over age under real world conditions.

  15. A Ground-Based Study on Extruder Standoff Distance for the 3D Printing in Zero Gravity Technology Demonstration Mission

    NASA Technical Reports Server (NTRS)

    Prater, T. J.; Bean, Q. A.; Werkheiser, N. J.; Beshears, R. D.; Rolin, T. D.; Rabenberg, E. M.; Soohoo, H. A.; Ledbetter, F. E., III; Bell, S. C.

    2017-01-01

    Analysis of phase I specimens produced as part of the 3D printing in zero G technology demonstration mission exhibited some differences in structure and performance for specimens printed onboard the International Space Station (ISS) and specimens produced on the ground with the same printer prior to its launch. This study uses the engineering test unit for the printer, identical to the unit on ISS, to conduct a ground-based investigation of the impact of the distance between the extruder tip and the build tray on material outcomes. This standoff distance was not held constant for the phase I flight prints and is hypothesized to be a major source of the material variability observed in the phase I data set.

  16. Long Period Ground Motion Prediction Of Linked Tonankai And Nankai Subduction Earthquakes Using 3D Finite Difference Method

    NASA Astrophysics Data System (ADS)

    Kawabe, H.; Kamae, K.

    2005-12-01

    There is high possibility of the occurrence of the Tonankai and Nankai earthquakes which are capable of causing immense damage. During these huge earthquakes, long period ground motions may strike mega-cities Osaka and Nagoya located inside the Osaka and Nobi basins in which there are many long period and low damping structures (such as tall buildings and oil tanks). It is very important for the earthquake disaster mitigation to predict long period strong ground motions of the future Tonankai and Nankai earthquakes that are capable of exciting long-period strong ground motions over a wide area. In this study, we tried to predict long-period ground motions of the future Tonankai and Nankai earthquakes using 3D finite difference method. We construct a three-dimensional underground structure model including not only the basins but also propagation field from the source to the basins. Resultantly, we can point out that the predominant periods of pseudo-velocity response spectra change basin by basin. Long period ground motions with periods of 5 to 8 second are predominant in the Osaka basin, 3 to 6 second in the Nobi basin and 2 to 5 second in the Kyoto basin. These characteristics of the long-period ground motions are related with the thicknesses of the sediments of the basins. The duration of long period ground motions inside the basin are more than 5 minutes. These results are very useful for the earthquake disaster mitigation of long period structures such as tall buildings and oil tanks.

  17. Quantitative, nondestructive estimates of coarse root biomass in a temperate pine forest using 3-D ground-penetrating radar (GPR)

    NASA Astrophysics Data System (ADS)

    Molon, Michelle; Boyce, Joseph I.; Arain, M. Altaf

    2017-01-01

    Coarse root biomass was estimated in a temperate pine forest using high-resolution (1 GHz) 3-D ground-penetrating radar (GPR). GPR survey grids were acquired across a 400 m2 area with varying line spacing (12.5 and 25 cm). Root volume and biomass were estimated directly from the 3-D radar volume by using isometric surfaces calculated with the marching cubes algorithm. Empirical relations between GPR reflection amplitude and root diameter were determined for 14 root segments (0.1-10 cm diameter) reburied in a 6 m2 experimental test plot and surveyed at 5-25 cm line spacing under dry and wet soil conditions. Reburied roots >1.4 cm diameter were detectable as continuous root structures with 5 cm line separation. Reflection amplitudes were strongly controlled by soil moisture and decreased by 40% with a twofold increase in soil moisture. GPR line intervals of 12.5 and 25 cm produced discontinuous mapping of roots, and GPR coarse root biomass estimates (0.92 kgC m-2) were lower than those obtained previously with a site-specific allometric equation due to nondetection of vertical roots and roots <1.5 cm diameter. The results show that coarse root volume and biomass can be estimated directly from interpolated 3-D GPR volumes by using a marching cubes approach, but mapping of roots as continuous structures requires high inline sampling and line density (<5 cm). The results demonstrate that 3-D GPR is viable approach for estimating belowground carbon and for mapping tree root architecture. This methodology can be applied more broadly in other disciplines (e.g., archaeology and civil engineering) for imaging buried structures.

  18. Ground-based Transit Observation of the Habitable-zone Super-Earth K2-3d

    NASA Astrophysics Data System (ADS)

    Fukui, Akihiko; Livingston, John; Narita, Norio; Hirano, Teruyuki; Onitsuka, Masahiro; Ryu, Tsuguru; Kusakabe, Nobuhiko

    2016-12-01

    We report the first ground-based transit observation of K2-3d, a 1.5 R ⊕ planet supposedly within the habitable zone around a bright M-dwarf host star, using the Okayama 188 cm telescope and the multi(grz)-band imager MuSCAT. Although the depth of the transit (0.7 mmag) is smaller than the photometric precisions (1.2, 0.9, and 1.2 mmag per 60 s for the g, r, and z bands, respectively), we marginally but consistently identify the transit signal in all three bands, by taking advantage of the transit parameters from K2, and by introducing a novel technique that leverages multi-band information to reduce the systematics caused by second-order extinction. We also revisit previously analyzed Spitzer transit observations of K2-3d to investigate the possibility of systematic offsets in transit timing, and find that all the timing data can be explained well by a linear ephemeris. We revise the orbital period of K2-3d to be 44.55612 ± 0.00021 days, which corrects the predicted transit times for 2019, i.e., the era of the James Webb Space Telescope, by ∼80 minutes. Our observation demonstrates that (1) even ground-based, 2 m class telescopes can play an important role in refining the transit ephemeris of small-sized, long-period planets, and (2) a multi-band imager is useful to reduce the systematics of atmospheric origin, in particular for bluer bands and for observations conducted at low-altitude observatories.

  19. Ground water in Pavant Valley

    USGS Publications Warehouse

    Dennis, P. E.; Maxey, G.B.; Thomas, H.E.

    1946-01-01

    The users of wells for irrigation in Pavant Valley, particularly in the Flowell district, have long been cognizant of their utter dependency upon ground water for livelihood, and were among the first in the State to make an organized effort to conserve supplies by prevention of waste. Since passage of the State ground-water law in 1935, the State Engineer has not approved applications for new wells in the areas of most concentrated development, and has deferred adjudication of existing water rights until adequate data concerning the ground-water resources become available. The investigation of ground-water resources in Pavant Valley was suggested by the State Engineer and constitutes one of a series that are being made in the important groundwater basins of Utah by the Federal Geological Survey in cooperation with the State Engineer. The investigation was under the general supervision of Oscar E. Meinzer, geologist in charge of the ground-water division of the Federal Geological Survey. H. E. Thomas, in charge of groundwater investigations in Utah, returned from military service overseas in time to assist in the completion of the manuscript, and edited the report.

  20. GROUND WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    EPA's Office of Research and Development operates a Ground Water Technical Support Center (GWTSC). The Center provides support on issues regarding subsurface contamination, contaminant fluxes to other media (e.g., surface water or air), and ecosystem restoration. The GWTSC creat...

  1. GROUND WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    EPA's Office of Research and Development operates a Ground Water Technical Support Center (GWTSC). The Center provides support on issues regarding subsurface contamination, contaminant fluxes to other media (e.g., surface water or air), and ecosystem restoration. The GWTSC creat...

  2. Ground water quality protection

    SciTech Connect

    Canter, L.W.; Fairchild, D.; Knox, R.C.

    1986-01-01

    Considered by the EPA to be one of the ''major Environmental Issues of the 1980s'' groundwater supplies a large majority of the water we use. Here is a book that deals with this problem. It is necessary that this problem be studied and action taken to prevent despoliation of the aquifers where this water is now found, because once contaminated an aquifer is difficult to decontaminate. CONTENTS-Groundwater: An Important Resource; Groundwater Hydrology; Groundwater Information Sources; Groundwater Pollution Sources; Pollutant Transport and Fate in the Subsurface Environment: Abiotic and Biotic Processes; Pollutant Transport and Fate in the Subsurface Environment: Hydrodynamic Processes and Flow and Solute Modeling; Pollution Source Evaluation; Empirical Assessment Methods; Groundwater Monitoring Planning; Groundwater Sampling and Analysis; Groundwater Quality Management; Groundwater Clean-up. References. Index.

  3. Use of 3D laser radar for navigation of unmanned aerial and ground vehicles in urban and indoor environments

    NASA Astrophysics Data System (ADS)

    Uijt de Haag, Maarten; Venable, Don; Smearcheck, Mark

    2007-04-01

    This paper discusses the integration of Inertial measurements with measurements from a three-dimensional (3D) imaging sensor for position and attitude determination of unmanned aerial vehicles (UAV) and autonomous ground vehicles (AGV) in urban or indoor environments. To enable operation of UAVs and AGVs at any time in any environment a Precision Navigation, Attitude, and Time (PNAT) capability is required that is robust and not solely dependent on the Global Positioning System (GPS). In urban and indoor environments a GPS position capability may not only be unavailable due to shadowing, significant signal attenuation or multipath, but also due to intentional denial or deception. Although deep integration of GPS and Inertial Measurement Unit (IMU) data may prove to be a viable solution an alternative method is being discussed in this paper. The alternative solution is based on 3D imaging sensor technologies such as Flash Ladar (Laser Radar). Flash Ladar technology consists of a modulated laser emitter coupled with a focal plane array detector and the required optics. Like a conventional camera this sensor creates an "image" of the environment, but producing a 2D image where each pixel has associated intensity vales the flash Ladar generates an image where each pixel has an associated range and intensity value. Integration of flash Ladar with the attitude from the IMU allows creation of a 3-D scene. Current low-cost Flash Ladar technology is capable of greater than 100 x 100 pixel resolution with 5 mm depth resolution at a 30 Hz frame rate. The proposed algorithm first converts the 3D imaging sensor measurements to a point cloud of the 3D, next, significant environmental features such as planar features (walls), line features or point features (corners) are extracted and associated from one 3D imaging sensor frame to the next. Finally, characteristics of these features such as the normal or direction vectors are used to compute the platform position and attitude

  4. Regional rigorous 3-D modelling of ground geoelectric field due to realistic geomagnetic disturbances. An approach and implementation.

    NASA Astrophysics Data System (ADS)

    Ivannikova, Elena; Kruglyakov, Mikhail; Kuvshinov, Alexey; Rastaetter, Lutz; Pulkkinen, Antti

    2017-04-01

    Strong eruptions at the Sun's surface produce large release of plasma, which with a high speed (solar wind) flows into space. Solar wind interaction with the Earth's magnetosphere and the ionosphere leads to a continuous disturbance of the geomagnetic field. This fluctuating geomagnetic field induces a ground geoelectric field that in turn generates geomagnetically induced currents (GICs) in technological systems, such as power grids and pipelines. It is well known that GICs are one of the most dangerous factors affecting the operation of the above systems. Thus, an accurate modelling of the spatio-temporal evolution of the geoelectric field during abnormal (storm-time) geomagnetic activity is a key consideration in estimating the hazard to technological systems from space weather. We present a numerical tool for regional modelling of the space weather influence on ground geoelectric field. The tool exploits realistic regional and global three-dimensional (3-D) models of Earth's electrical conductivity, and realistic global models of the spatio-temporal evolution of magnetospheric and ionospheric current systems responsible for geomagnetic disturbances. The tool involves four steps. First, we compute the spatio-temporal distribution of external magnetic field on a regular grid at the surface of the Earth using a magnetohydrodynamic model of the magnetosphere coupled to an electrostatic model of the ionosphere. Second, from the external magnetic field we compute the global source in the form of equivalent currents flowing in a thin shell above the Earth. Third, for a given global source and a given global 3-D conductivity model of the Earth we compute ground geoelectric field globally at a coarse grid (using spherical geometry). Finally, for a given source and a given regional 3-D conductivity model(s) of the Earth we compute geoelectric field regionally (using Cartesian geometry) at a dense grid utilizing the results from the global modelling. Both global and

  5. Quasi 3D modeling of water flow and solute transport in vadose zone and groundwater

    NASA Astrophysics Data System (ADS)

    Yakirevich, A.; Kuznetsov, M.; Weisbrod, N.; Pachepsky, Y. A.

    2013-12-01

    The complexity of subsurface flow systems calls for a variety of concepts leading to the multiplicity of simplified flow models. One commonly used simplification is based on the assumption that lateral flow and transport in unsaturated zone is insignificant unless the capillary fringe is involved. In such cases the flow and transport in the unsaturated zone above groundwater level can be simulated as a 1D phenomenon, whereas through groundwater they are viewed as 2D or 3D phenomena. A new approach for a numerical scheme for 3D variably saturated flow and transport is presented. A Quasi-3D approach allows representing flow in the 'vadose zone - aquifer' system by a series of 1D Richards' equations solved in variably-saturated zone and by 3D-saturated flow equation in groundwater (modified MODFLOW code). The 1D and 3D equations are coupled at the phreatic surface in a way that aquifer replenishment is calculated using the Richards' equation, and solving for the moving water table does not require definition of the specific yield parameter. The 3D advection-dispersion equation is solved in the entire domain by the MT3D code. Using implicit finite differences approximation to couple processes in the vadose zone and groundwater provides mass conservation and increase of computational efficiency. The above model was applied to simulate the impact of irrigation on groundwater salinity in the Alto Piura aquifer (Northern Peru). Studies on changing groundwater quality in arid and semi-arid lands show that irrigation return flow is one of the major factors contributing to aquifer salinization. Existing mathematical models do not account explicitly for the solute recycling during irrigation on a daily scale. Recycling occurs throughout the unsaturated and saturated zones, as function of the solute mass extracted from pumping wells. Salt concentration in irrigation water is calculated at each time step as a function of concentration of both surface water and groundwater

  6. Radon in ground water supplies

    SciTech Connect

    Dixon, K.L.; Lee, R.G.

    1989-06-01

    In September 1986, the System Water Quality Department of the American Water Works Service Co. began conducting a radon survey that was designed to determine the levels of radon in American ground water supplies, and to assess the radon removal efficiency of existing treatment processes such as filtration through granular activated carbon (GAC) and various forms of aeration. The survey found that companies in the northeastern part of the country experienced the highest levels of radon in ground water supplies. The highest concentrations were in individual wells in New Hampshire, Maryland, Connecticut, Rhode Island, New Jersey, Pennsylvania and California. The analytical results from the occurrence phase of the survey seemed to correlate well with the known geology of the aquifer materials from which samples of ground water were drawn. The highest levels were associated with formations of uranium-bearing granitic rocks. GAC can effectively reduce radon concentrations in drinking water supplies to very low levels. However, the amount of contact time within the carbon bed required to do so would be prohibitive to many water utilities from an operational and economic standpoint. Further, disposal of the spent GAC as a low-level radioactive waste may be required. Aeration is very effective in the removal of radon from drinking water. Packed tower aerators achieved > 95% reduction in radon concentrations and conventional cascading tray aerators achieved > 75% reduction in radon concentrations. 7 refs., 6 tabs.

  7. Microbiology of potable water and ground water

    SciTech Connect

    Allen, M.J.

    1982-06-01

    A literature review dealing with the microbiology of potable water and ground water is presented. In recent years, there has been increased interest in the use of granular activated carbon (GAC) and alternate disinfection practices to reduce trihalomethane. Results of studies utilizing GAC columns are reported as well as studies evaluating ozone, chlorine dioxide, and chloromines. Virus removal efficiencies were compared with several disinfectants. Ground water studies demonstrate that biological contaminants can travel large distances underground without substantial attenuation by aquifer material.(KRM)

  8. Assessing soil water storage distribution under sprinkler irrigation by coupling 3D simulations and field observations

    NASA Astrophysics Data System (ADS)

    Taha, Uday; Shabeeb, Ahmed; dragonetti, giovanna; Lamaddalena, Nicola; Coppola, Antonio

    2016-04-01

    This work analyzed the variability of sprinkler irrigation application over a bare soil, both in terms of water application efficiency and uniformity, by integrating and comparing the information on the irrigation depth data (ID), as measured by catch cans, soil water storage in the upper root zone, as measured by TDR probes, and a 3D simulations of water flow in soils. Three irrigation tests were performed at three different pressures (2, 3 and 4 bar). A lateral water redistribution was observed and simulated after each irrigation event by comparing spatial distributions of site-specific water application efficiency (AEs), as well as ratios of site-specific actual water storage increase (SWEs) and irrigation depth (IDs) to the water content before irrigation. Because of soil water redistribution processes, distribution uniformity based on soil storages was systematically higher than the catch can uniformity. The obvious consequence of lateral water redistribution processes was that the soil smoothing action on non-uniformity observed at the surface increased both with depth and over time. At a given depth the uniformity of soil water storages always attained the same value, whatever the pressure considered and the catch can-based uniformity coefficient. It was concluded that, for the case of random distribution of ID, the uniformity of water storages is driven by the soil behavior rather than by the irrigation system.

  9. Combining 3D seismic tomography and ground-penetrating radar to reveal the structure of a megalithic burial tomb

    NASA Astrophysics Data System (ADS)

    Mendes, Manuela; Caldeira, Bento; Borges, José

    2017-04-01

    This work describes a case study concerning a prehistoric buried tomb (around 3000 years B.C.) located near Évora (Portugal). This monument is a tomb completely buried with only five visible irregular small stones distributed in a circle of 3 meter in diameter. A multi-approach combining 3D seismic tomography and ground-penetrating radar (GPR) have been applied to identify hidden elements and arrangement of the stones, required prior to any excavation work. The methodology for the 3D seismic data acquisition involves a total of 24 shots recorded by four lines, with twelve fixed receivers each one. For the GPR survey was used a 400 MHz antenna which moves along parallel lines with 50 cm separation, over a 30x30 m2 area that contains the buried tomb; the GPR unit was configured to a horizontal rate of 50 scans per meter (1024 samples/scan) and a time window of 60 ns. This multi-approach procedure allowed defining: (i) the housing of the tomb in the basement structure; (ii) the presence of a hidden corridor; (iii) the description of the internal structure of the walls of the tomb; (iv) the state of preservation of the monument. Acknowledgements: This work is co-financed by the European Union through the European Regional Development Fund under COMPETE 2020 (Operational Program for Competitiveness and Internationalization) through the ICT project (UID / GEO / 04683/2013) under the reference POCI-01-0145 -FEDER-007690.

  10. A large dataset of synthetic SEM images of powder materials and their ground truth 3D structures.

    PubMed

    DeCost, Brian L; Holm, Elizabeth A

    2016-12-01

    This data article presents a data set comprised of 2048 synthetic scanning electron microscope (SEM) images of powder materials and descriptions of the corresponding 3D structures that they represent. These images were created using open source rendering software, and the generating scripts are included with the data set. Eight particle size distributions are represented with 256 independent images from each. The particle size distributions are relatively similar to each other, so that the dataset offers a useful benchmark to assess the fidelity of image analysis techniques. The characteristics of the PSDs and the resulting images are described and analyzed in more detail in the research article "Characterizing powder materials using keypoint-based computer vision methods" (B.L. DeCost, E.A. Holm, 2016) [1]. These data are freely available in a Mendeley Data archive "A large dataset of synthetic SEM images of powder materials and their ground truth 3D structures" (B.L. DeCost, E.A. Holm, 2016) located at http://dx.doi.org/10.17632/tj4syyj9mr.1[2] for any academic, educational, or research purposes.

  11. 3D realtime echography and echography assisted by a robotic arm for investigating astronauts in the ISS from the ground.

    PubMed

    Arbeille, P; Herault, S; Roumy, J; Porcher, M; Besnard, S; Vieyres, P

    2001-07-01

    As human will stay for long duration in isolated sites like ISS there will be a need to perform quick and reliable diagnosis to evaluate the gravity of the pathology in presence of clinical symptoms. Many pathological situations (abnormal heart rate, pericardic collection, mitral prolaps, cholecystis, renal lithiasis, normal and ectopic pregnancies, ovarian cyst, acute appendicitis, phlebitis ... ) may occur even if all the astronauts are absolutely normal and healthy preflight. Ultrasound echography and Doppler are non invasive methods easy to use in space and very well adapted and used in routine for such diagnosis at the hospital. The objective of the present project was to design a method that guarantee a reliable echographic diagnostic in an isolated site (space station or earth site) by a Medical Doctor located at the expert site that should be the Nasa control center for ISS. It is supposed that there is only a non sonographer person in the isolated site and that the transmission system (audio, video, numeric..) is the only link between the 2 sites. Two options are proposed: (a) A 3D realtime acquisition echograph that can record quickly all the echos of a volume containing the organ suspected to have a lesion, all these echo information being sent to the ground and processed by the ground experts, (b) A robotic arm that hangs the echo probe in the isolated site tele-operated (through sattelite network) from the ground by an expert in clinical ultrasound. (As the expert moves the joystick of his ground computer the robotic arm reproduces the same movements on the probe).

  12. COMPILATION OF GROUND WATER MODELS

    EPA Science Inventory

    The full report presents an overview of currently available computer-based simulation models for ground-water flow, solute and heat transport, and hydrogeochemistry in both porous media and fractured rock. Separate sections address multiphase flow and related chemical species tra...

  13. COMPILATION OF GROUND WATER MODELS

    EPA Science Inventory

    The full report presents an overview of currently available computer-based simulation models for ground-water flow, solute and heat transport, and hydrogeochemistry in both porous media and fractured rock. Separate sections address multiphase flow and related chemical species tra...

  14. GROUND WATER SAMPLING FOR VOCS

    EPA Science Inventory

    Sampling protocol should be dictated by the sampling objective(s). It is important to obtain representative ground water samples, regardless of the sampling objective(s). Low-flow (minimum draw-down) purging and sampling techniques are best in most instances, particularly for VOC...

  15. Death Valley regional ground-water flow system, Nevada and California -- hydrogeologic framework and transient ground-water flow model

    USGS Publications Warehouse

    : Belcher, Wayne R.

    2004-01-01

    A numerical three-dimensional (3D) transient ground-water flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the ground-water flow system and previous less extensive ground-water flow models were incorporated and reevaluated together with new data to provide greater detail for the complex, digital model. A 3D digital hydrogeologic framework model (HFM) was developed from digital elevation models, geologic maps, borehole information, geologic and hydrogeologic cross sections, and other 3D models to represent the geometry of the hydrogeologic units (HGUs). Structural features, such as faults and fractures, that affect ground-water flow also were added. The HFM represents Precambrian and Paleozoic crystalline and sedimentary rocks, Mesozoic sedimentary rocks, Mesozoic to Cenozoic intrusive rocks, Cenozoic volcanic tuffs and lavas, and late Cenozoic sedimentary deposits of the Death Valley Regional Ground-Water Flow System (DVRFS) region in 27 HGUs. Information from a series of investigations was compiled to conceptualize and quantify hydrologic components of the ground-water flow system within the DVRFS model domain and to provide hydraulic-property and head-observation data used in the calibration of the transient-flow model. These studies reevaluated natural ground-water discharge occurring through evapotranspiration and spring flow; the history of ground-water pumping from 1913 through 1998; ground-water recharge simulated as net infiltration; model boundary inflows and outflows based on regional hydraulic gradients and water budgets of surrounding areas; hydraulic conductivity and its relation to depth; and water levels appropriate for regional simulation of prepumped and pumped conditions within the DVRFS model domain. Simulation results appropriate for the regional extent and scale of the model were

  16. 3-D or median map? Earthquake scenario ground-motion maps from physics-based models versus maps from ground-motion prediction equations

    NASA Astrophysics Data System (ADS)

    Porter, K.

    2015-12-01

    There are two common ways to create a ground-motion map for a hypothetical earthquake: using ground motion prediction equations (by far the more common of the two) and using 3-D physics-based modeling. The former is very familiar to engineers, the latter much less so, and the difference can present a problem because engineers tend to trust the familiar and distrust novelty. Maps for essentially the same hypothetical earthquake using the two different methods can look very different, while appearing to present the same information. Using one or the other can lead an engineer or disaster planner to very different estimates of damage and risk. The reasons have to do with depiction of variability, spatial correlation of shaking, the skewed distribution of real-world shaking, and the upward-curving relationship between shaking and damage. The scientists who develop the two kinds of map tend to specialize in one or the other and seem to defend their turf, which can aggravate the problem of clearly communicating with engineers.The USGS Science Application for Risk Reduction's (SAFRR) HayWired scenario has addressed the challenge of explaining to engineers the differences between the two maps, and why, in a disaster planning scenario, one might want to use the less-familiar 3-D map.

  17. Continental water storage inferred from 3-D GPS coordinates in Danube Basin

    NASA Astrophysics Data System (ADS)

    van Dam, T. M.; Wang, L.; Weigelt, M. L. B.; Tourian, M. J.; Chen, Q.; Sneeuw, N. J.

    2014-12-01

    GPS coordinates time series contain viable information about continental water storage (CWS) at global and regional scale. The permanent GPS network of GPS stations around the Earth recorded more than 15 years of data, which comprise the elastic response of the bed rock movements induced by mass loading. The inversion of the observed displacements, yields mass variations which can be interpreted as CWS under the condition that no other mass loading is interfering. GPS-derived CWS offers complimentary information to the widely used CWS determination by GRACE but is also able to mitigate a possible loss of data in case the GRACE mission ends before the launch of the GRACE Follow-On mission. GPS also allows increasing the temporal resolution (weekly from GPS versus monthly from GRACE) and the spatial resolution (especially in the regions with dense GPS networks). Here, we determine the weekly mass variations from GPS 3-D coordinates by using mass-loading Green's function in six Danube sub-basins. The results are validated against GRACE and hydro-meteorological models. We also demonstrate the contribution of GPS horizontals for regional water storage and provide insights into the benefits and limitations of 3-D GPS inversions for regional water storage.

  18. A 3D triple-deck photoanode with a strengthened structure integrality: enhanced photoelectrochemical water oxidation

    NASA Astrophysics Data System (ADS)

    Ma, Ming; Shi, Xinjian; Zhang, Kan; Kwon, Soonwoo; Li, Ping; Kim, Jung Kyu; Phu, Thanh Tran; Yi, Gi-Ra; Park, Jong Hyeok

    2016-02-01

    WO3/BiVO4 is one of the attractive Type II heterojunctions for photoelectrochemical (PEC) water splitting due to its well-matched band edge positions and visible light harvesting abilities. However, two light absorption components generally suffer from poor charge collection and cannot be efficiently utilized because of non-ideal interfaces. Herein, a triple-deck three-dimensional (3D) architecture was designed through a one-step shaping process with an additional stress relaxation WO3 underlayer. The final photoanodes showed a promising photocurrent density of 5.1 mA cm-2 at 1.23 V vs. RHE under AM 1.5G illumination. Using the uniformly distributed oxygen evolution co-catalyst (OEC) layer as the outer most shell of the WO3/BiVO4/OEC triple-deck 3D structure with a dense WO3 underlayer, the water splitting efficiency was improved dramatically by facilitating the charge transfer process at the electrode/electrolyte interface.WO3/BiVO4 is one of the attractive Type II heterojunctions for photoelectrochemical (PEC) water splitting due to its well-matched band edge positions and visible light harvesting abilities. However, two light absorption components generally suffer from poor charge collection and cannot be efficiently utilized because of non-ideal interfaces. Herein, a triple-deck three-dimensional (3D) architecture was designed through a one-step shaping process with an additional stress relaxation WO3 underlayer. The final photoanodes showed a promising photocurrent density of 5.1 mA cm-2 at 1.23 V vs. RHE under AM 1.5G illumination. Using the uniformly distributed oxygen evolution co-catalyst (OEC) layer as the outer most shell of the WO3/BiVO4/OEC triple-deck 3D structure with a dense WO3 underlayer, the water splitting efficiency was improved dramatically by facilitating the charge transfer process at the electrode/electrolyte interface. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08604c

  19. A 3-D implicit finite-volume model of shallow water flows

    NASA Astrophysics Data System (ADS)

    Wu, Weiming; Lin, Qianru

    2015-09-01

    A three-dimensional (3-D) model has been developed to simulate shallow water flows in large water bodies, such as coastal and estuarine waters. The eddy viscosity is determined using a newly modified mixing length model that uses different mixing length functions for the horizontal and vertical shear strain rates. The 3-D shallow water flow equations with the hydrostatic pressure assumption are solved using an implicit finite-volume method based on a quadtree (telescoping) rectangular mesh on the horizontal plane and the sigma coordinate in the vertical direction. The quadtree technique can locally refine the mesh around structures or in high-gradient regions by splitting a coarse cell into four child cells. The grid nodes are numbered with a one-dimensional index system that has unstructured grid feature for better grid flexibility. All the primary variables are arranged in a non-staggered grid system. Fluxes at cell faces are determined using a Rhie and Chow-type momentum interpolation, to avoid the possible spurious checkerboard oscillations caused by linear interpolation. Each of the discretized governing equations is solved iteratively using the flexible GMRES method with ILUT preconditioning, and coupling of water level and velocity among these equations is achieved by using the SIMPLEC algorithm with under-relaxation. The model has been tested in four cases, including steady flow near a spur-dyke, tidal flows in San Francisco Bay and Gironde Estuary, and wind-induced current in a flume. The calculated water levels and velocities are in good agreement with the measured values.

  20. 3D fault curvature and fractal roughness: Insights for rupture dynamics and ground motions using a Discontinous Galerkin method

    NASA Astrophysics Data System (ADS)

    Ulrich, Thomas; Gabriel, Alice-Agnes

    2017-04-01

    Natural fault geometries are subject to a large degree of uncertainty. Their geometrical structure is not directly observable and may only be inferred from surface traces, or geophysical measurements. Most studies aiming at assessing the potential seismic hazard of natural faults rely on idealised shaped models, based on observable large-scale features. Yet, real faults are wavy at all scales, their geometric features presenting similar statistical properties from the micro to the regional scale. Dynamic rupture simulations aim to capture the observed complexity of earthquake sources and ground-motions. From a numerical point of view, incorporating rough faults in such simulations is challenging - it requires optimised codes able to run efficiently on high-performance computers and simultaneously handle complex geometries. Physics-based rupture dynamics hosted by rough faults appear to be much closer to source models inverted from observation in terms of complexity. Moreover, the simulated ground-motions present many similarities with observed ground-motions records. Thus, such simulations may foster our understanding of earthquake source processes, and help deriving more accurate seismic hazard estimates. In this presentation, the software package SeisSol (www.seissol.org), based on an ADER-Discontinuous Galerkin scheme, is used to solve the spontaneous dynamic earthquake rupture problem. The usage of tetrahedral unstructured meshes naturally allows for complicated fault geometries. However, SeisSol's high-order discretisation in time and space is not particularly suited for small-scale fault roughness. We will demonstrate modelling conditions under which SeisSol resolves rupture dynamics on rough faults accurately. The strong impact of the geometric gradient of the fault surface on the rupture process is then shown in 3D simulations. Following, the benefits of explicitly modelling fault curvature and roughness, in distinction to prescribing heterogeneous initial

  1. Deriving the Properties of Coronal Pressure Fronts in 3D: Application to the 2012 May 17 Ground Level Enhancement

    NASA Astrophysics Data System (ADS)

    Rouillard, A. P.; Plotnikov, I.; Pinto, R. F.; Tirole, M.; Lavarra, M.; Zucca, P.; Vainio, R.; Tylka, A. J.; Vourlidas, A.; De Rosa, M. L.; Linker, J.; Warmuth, A.; Mann, G.; Cohen, C. M. S.; Mewaldt, R. A.

    2016-12-01

    We study the link between an expanding coronal shock and the energetic particles measured near Earth during the ground level enhancement of 2012 May 17. We developed a new technique based on multipoint imaging to triangulate the three-dimensional (3D) expansion of the shock forming in the corona. It uses images from three vantage points by mapping the outermost extent of the coronal region perturbed by the pressure front. We derive for the first time the 3D velocity vector and the distribution of Mach numbers, M FM, of the entire front as a function of time. Our approach uses magnetic field reconstructions of the coronal field, full magnetohydrodynamic simulations and imaging inversion techniques. We find that the highest M FM values appear near the coronal neutral line within a few minutes of the coronal mass ejection onset; this neutral line is usually associated with the source of the heliospheric current and plasma sheet. We illustrate the variability of the shock speed, shock geometry, and Mach number along different modeled magnetic field lines. Despite the level of uncertainty in deriving the shock Mach numbers, all employed reconstruction techniques show that the release time of GeV particles occurs when the coronal shock becomes super-critical (M FM > 3). Combining in situ measurements with heliospheric imagery, we also demonstrate that magnetic connectivity between the accelerator (the coronal shock of 2012 May 17) and the near-Earth environment is established via a magnetic cloud that erupted from the same active region roughly five days earlier.

  2. A 3D triple-deck photoanode with a strengthened structure integrality: enhanced photoelectrochemical water oxidation.

    PubMed

    Ma, Ming; Shi, Xinjian; Zhang, Kan; Kwon, Soonwoo; Li, Ping; Kim, Jung Kyu; Phu, Thanh Tran; Yi, Gi-Ra; Park, Jong Hyeok

    2016-02-14

    WO3/BiVO4 is one of the attractive Type II heterojunctions for photoelectrochemical (PEC) water splitting due to its well-matched band edge positions and visible light harvesting abilities. However, two light absorption components generally suffer from poor charge collection and cannot be efficiently utilized because of non-ideal interfaces. Herein, a triple-deck three-dimensional (3D) architecture was designed through a one-step shaping process with an additional stress relaxation WO3 underlayer. The final photoanodes showed a promising photocurrent density of 5.1 mA cm(-2) at 1.23 V vs. RHE under AM 1.5G illumination. Using the uniformly distributed oxygen evolution co-catalyst (OEC) layer as the outer most shell of the WO3/BiVO4/OEC triple-deck 3D structure with a dense WO3 underlayer, the water splitting efficiency was improved dramatically by facilitating the charge transfer process at the electrode/electrolyte interface.

  3. Mechanisms driving estuarine water quality: A 3D biogeochemical model for informed management

    NASA Astrophysics Data System (ADS)

    Wild-Allen, Karen; Skerratt, Jenny; Whitehead, Jason; Rizwi, Farhan; Parslow, John

    2013-12-01

    Estuaries are amongst the most productive marine ecosystems of the world but are also some of the most degraded due to coastal urban development. Sparse sampling of complex interactions between estuarine physics, sediment transport, chemistry, and biology limits understanding of the processes controlling estuarine water quality and confounds active management. We use a 3D coupled hydrodynamic, sediment and biogeochemical model to identify the key mechanisms driving fine-scale fluctuations in water quality in a temperate micro-tidal salt wedge estuary [Derwent Estuary, Tasmania]. Model results are dynamically consistent with relatively sparse monitoring data collected over a seasonal cycle and are considered to be a plausible hypothesis of sub-monitoring scale processes occurring in the estuary. The model shows enhanced mixing of nutrients across the pycnocline downstream of the salt wedge front that supports a persistent phytoplankton bloom. The length and flow regime of the estuary results in nutrient recycling and retention in the estuarine circulation driving a decline in bottom water dissolved oxygen in the mid- and upper-reaches. A budget analysis of modelled nitrogen suggests high levels of denitrification are critical to the maintenance of existing water quality. Active estuarine management focused on the improvement of bottom water dissolved oxygen for ecological health reasons must either concurrently reduce anthropogenic nitrogen loads or be sure to maintain high levels of microbial denitrification for net water quality improvement.

  4. 3D Imaging of Water-Drop Condensation on Hydrophobic and Hydrophilic Lubricant-Impregnated Surfaces

    PubMed Central

    Kajiya, Tadashi; Schellenberger, Frank; Papadopoulos, Periklis; Vollmer, Doris; Butt, Hans-Jürgen

    2016-01-01

    Condensation of water from the atmosphere on a solid surface is an ubiquitous phenomenon in nature and has diverse technological applications, e.g. in heat and mass transfer. We investigated the condensation kinetics of water drops on a lubricant-impregnated surface, i.e., a micropillar array impregnated with a non-volatile ionic liquid. Growing and coalescing drops were imaged in 3D using a laser scanning confocal microscope equipped with a temperature and humidity control. Different stages of condensation can be discriminated. On a lubricant-impregnated hydrophobic micropillar array these are: (1) Nucleation on the lubricant surface. (2) Regular alignment of water drops between micropillars and formation of a three-phase contact line on a bottom of the substrate. (3) Deformation and bridging by coalescence which eventually leads to a detachment of the drops from the bottom substrate. The drop-substrate contact does not result in breakdown of the slippery behaviour. Contrary, on a lubricant-impregnated hydrophilic micropillar array, the condensed water drops replace the lubricant. Consequently, the surface loses its slippery property. Our results demonstrate that a Wenzel-like to Cassie transition, required to maintain the facile removal of condensed water drops, can be induced by well-chosen surface hydrophobicity. PMID:27040483

  5. 3D Imaging of Water-Drop Condensation on Hydrophobic and Hydrophilic Lubricant-Impregnated Surfaces

    NASA Astrophysics Data System (ADS)

    Kajiya, Tadashi; Schellenberger, Frank; Papadopoulos, Periklis; Vollmer, Doris; Butt, Hans-Jürgen

    2016-04-01

    Condensation of water from the atmosphere on a solid surface is an ubiquitous phenomenon in nature and has diverse technological applications, e.g. in heat and mass transfer. We investigated the condensation kinetics of water drops on a lubricant-impregnated surface, i.e., a micropillar array impregnated with a non-volatile ionic liquid. Growing and coalescing drops were imaged in 3D using a laser scanning confocal microscope equipped with a temperature and humidity control. Different stages of condensation can be discriminated. On a lubricant-impregnated hydrophobic micropillar array these are: (1) Nucleation on the lubricant surface. (2) Regular alignment of water drops between micropillars and formation of a three-phase contact line on a bottom of the substrate. (3) Deformation and bridging by coalescence which eventually leads to a detachment of the drops from the bottom substrate. The drop-substrate contact does not result in breakdown of the slippery behaviour. Contrary, on a lubricant-impregnated hydrophilic micropillar array, the condensed water drops replace the lubricant. Consequently, the surface loses its slippery property. Our results demonstrate that a Wenzel-like to Cassie transition, required to maintain the facile removal of condensed water drops, can be induced by well-chosen surface hydrophobicity.

  6. Simulation of water temperature in two reservoirs with Delft3d

    NASA Astrophysics Data System (ADS)

    Yang, J. Y.; Zhou, L. Y.

    2016-08-01

    The proposeled Guanjingkou and Fengdou reservoir will be constructed at Chongqing city and Muling city in China respectively. The water temperature in the reservoir, in the downstream, and the aquatic ecosystem would be altered by the construction of the reservoirs. This paper simulates the water temperature in the two reservoirs by using the Delft3d z-layer model, which uses the fixed elevation for layers. According to the simulation results, the temperature profile in the reservoirs can be divided into three layers: the upmost epilimnion layer, the beneathed thermocline layer, and the constant tepmerature layer at bottom. The temperature effects can be reduced by measurements of stoplogs gates and mutiple gates, respectively. Based on the simulation results in the wet, nomal, and dry year, the temperature of water released from the stoplogs gates at Guanjingkou reservior can be respectively increased by 5.7°C, 6.8°C, 9.6°C, and 5.5°C in the irrigation season from May to August. The temperature of water released from the mutiple gates at Fengdou reservior can be respectively increased by 7.7 °C, 1.9 °C, 9.5 °C, and 10.1 °C from May to August. The negative impacts from the water with lower temperature on the related ecosystem can be significently alleviated.

  7. Characterization of shallow normal fault systems in unconsolidated sediments using 3-D ground penetrating radar (SE Vienna Basin, Austria)

    NASA Astrophysics Data System (ADS)

    Spahic, D.; Exner, U.; Behm, M.; Grasemann, B.; Haring, A.

    2009-04-01

    In a gravel pit at the eastern margin of the Eisenstadt Basin, a subbasin of Vienna Basin (Austria), a set of normal faults crosscuts a Middle Miocene succession consisting of gravel layers, sandy gravels, fine-grained sands and silts with variable thicknesses between 1 and 4 m. These mainly friable sediments are cut by a numerous N-S striking high angle normal faults of ca. 0.5 - 10m length, offsetting, dragging and tilting the sedimentary layering. Normal faults occur either as isolated planes, or as parallel sets of high-angle faults dipping to the West. The outcrop is situated in the hanging wall of a major normal fault with a vertical displacement of at least 40m, which was interpreted as listric fault associated with a rollover anticline (Decker & Peresson, 1996). The displacement magnitude varies significantly along individual faults from cm to a few meters. The strong displacement gradients along these short faults result in the formation of perturbation fields around them, which deflect the initially planar sedimentary marker beds in the vicinity of the faults producing a pronounced reverse fault drag. None of these short faults display listric geometries or are associated with low angle detachment horizons. The spatial orientation and distribution of the faults and the associated fault drag was mapped in detail on a 3D laser scan of the outcrop wall. In order to assess the 3D distribution and geometry of this fault system, a series of parallel GPR (ground penetrating radar) profiles were recorded with a low frequency antenna behind the well-studied outcrop wall. The profile data were interpolated into a 3D GPR cube. Faults with normal offset of ca. 0.5-1,5 m can be mapped by detailed correlation of conspicuous marker horizons. Additionally, the deflection of markers around the fault planes can be documented from the GPR dataset. Both outcrop and GPR data were compiled in a 3D structural model using Gocad (Paradigm). The detailed geometry of the

  8. A 3-D view of field-scale fault-zone cementation from geologically ground-truthed electrical resistivity

    NASA Astrophysics Data System (ADS)

    Barnes, H.; Spinelli, G. A.; Mozley, P.

    2015-12-01

    Fault-zones are an important control on fluid flow, affecting groundwater supply, hydrocarbon/contaminant migration, and waste/carbon storage. However, current models of fault seal are inadequate, primarily focusing on juxtaposition and entrainment effects, despite the recognition that fault-zone cementation is common and can dramatically reduce permeability. We map the 3D cementation patterns of the variably cemented Loma Blanca fault from the land surface to ~40 m depth, using electrical resistivity and induced polarization (IP). The carbonate-cemented fault zone is a region of anomalously low normalized chargeability, relative to the surrounding host material. Zones of low-normalized chargeability immediately under the exposed cement provide the first ground-truth that a cemented fault yields an observable IP anomaly. Low-normalized chargeability extends down from the surface exposure, surrounded by zones of high-normalized chargeability, at an orientation consistent with normal faults in the region; this likely indicates cementation of the fault zone at depth, which could be confirmed by drilling and coring. Our observations are consistent with: 1) the expectation that carbonate cement in a sandstone should lower normalized chargeability by reducing pore-surface area and bridging gaps in the pore space, and 2) laboratory experiments confirming that calcite precipitation within a column of glass beads decreases polarization magnitude. The ability to characterize spatial variations in the degree of fault-zone cementation with resistivity and IP has exciting implications for improving predictive models of the hydrogeologic impacts of cementation within faults.

  9. Hierarchically 3D assembled strontium titanate nanomaterials for water splitting application

    NASA Astrophysics Data System (ADS)

    Moniruddin, Md; Afroz, Khurshida; Shabdan, Yerkin; Bizri, Baraa; Nuraje, Nurxat

    2017-10-01

    Water splitting is an important technique to store solar energy in the simple form of chemical energy, such as hydrogen. Strontium titanate (SrTiO3) is one of the most promising photocatalysts to produce hydrogen gas from water splitting. In this research, an electrospinning technique in combination with sol-gel method was developed to synthesize 3D porous SrTiO3 nanostructures. Different crystallite sizes of SrTiO3-nanofibers (STO-NFs) were produced by varying the synthesis parameters including precursor concentration and calcination temperature. The synthesized nanofibers were characterized using DSC, TGA, XRD, SEM, and TEM. The crystallite size of STO-NFs decreases with increasing precursor concentration (3.03-15.78 vol.%) and gradually increases as the calcination temperature increases within the range of 600-800 °C. The photocatalytic activity of different STO-NFs (based on crystallite size) was also evaluated by the amount of H2 production from water splitting under UV irradiation. The H2 evolution study demonstrated that the photocatalytic activity of the STO-NFs strongly depends on the crystallite size of the nanofibers, precursor concentration, and calcination temperature. The H2 production rate increases with increasing crystallite size and temperature, whereas it decreases with increasing precursor concentration. The photocatalytic performance of the STO-NFs was also compared with the commercial SrTiO3 nanoparticles (STO-NPs) after Pt addition as a cocatalyst, where the synthesized nanofibers showed 2 times higher H2 production rate (1.14 mmol/g-h) than that of the nanoparticles. This synthesis technique provides a good example to produce other inorganic photocatalytic 3D porous structure materials.

  10. 3D Simulation of Missing Pellet Surface Defects in Light Water Reactor Fuel Rods

    SciTech Connect

    B.W. Spencer; J.D. Hales; S.R. Novascone; R.L. Williamson

    2012-09-01

    The cladding on light water reactor (LWR) fuel rods provides a stable enclosure for fuel pellets and serves as a first barrier against fission product release. Consequently, it is important to design fuel to prevent cladding failure due to mechanical interactions with fuel pellets. Cladding stresses can be effectively limited by controlling power increase rates. However, it has been shown that local geometric irregularities caused by manufacturing defects known as missing pellet surfaces (MPS) in fuel pellets can lead to elevated cladding stresses that are sufficiently high to cause cladding failure. Accurate modeling of these defects can help prevent these types of failures. Nuclear fuel performance codes commonly use a 1.5D (axisymmetric, axially-stacked, one-dimensional radial) or 2D axisymmetric representation of the fuel rod. To study the effects of MPS defects, results from 1.5D or 2D fuel performance analyses are typically mapped to thermo-mechanical models that consist of a 2D plane-strain slice or a full 3D representation of the geometry of the pellet and clad in the region of the defect. The BISON fuel performance code developed at Idaho National Laboratory employs either a 2D axisymmetric or 3D representation of the full fuel rod. This allows for a computational model of the full fuel rod to include local defects. A 3D thermo-mechanical model is used to simulate the global fuel rod behavior, and includes effects on the thermal and mechanical behavior of the fuel due to accumulation of fission products, fission gas production and release, and the effects of fission gas accumulation on thermal conductivity across the fuel-clad gap. Local defects can be modeled simply by including them in the 3D fuel rod model, without the need for mapping between two separate models. This allows for the complete set of physics used in a fuel performance analysis to be included naturally in the computational representation of the local defect, and for the effects of the

  11. Calculating the Probability of Strong Ground Motions Using 3D Seismic Waveform Modeling - SCEC CyberShake

    NASA Astrophysics Data System (ADS)

    Gupta, N.; Callaghan, S.; Graves, R.; Mehta, G.; Zhao, L.; Deelman, E.; Jordan, T. H.; Kesselman, C.; Okaya, D.; Cui, Y.; Field, E.; Gupta, V.; Vahi, K.; Maechling, P. J.

    2006-12-01

    Researchers from the SCEC Community Modeling Environment (SCEC/CME) project are utilizing the CyberShake computational platform and a distributed high performance computing environment that includes USC High Performance Computer Center and the NSF TeraGrid facilities to calculate physics-based probabilistic seismic hazard curves for several sites in the Southern California area. Traditionally, probabilistic seismic hazard analysis (PSHA) is conducted using intensity measure relationships based on empirical attenuation relationships. However, a more physics-based approach using waveform modeling could lead to significant improvements in seismic hazard analysis. Members of the SCEC/CME Project have integrated leading-edge PSHA software tools, SCEC-developed geophysical models, validated anelastic wave modeling software, and state-of-the-art computational technologies on the TeraGrid to calculate probabilistic seismic hazard curves using 3D waveform-based modeling. The CyberShake calculations for a single probablistic seismic hazard curve require tens of thousands of CPU hours and multiple terabytes of disk storage. The CyberShake workflows are run on high performance computing systems including multiple TeraGrid sites (currently SDSC and NCSA), and the USC Center for High Performance Computing and Communications. To manage the extensive job scheduling and data requirements, CyberShake utilizes a grid-based scientific workflow system based on the Virtual Data System (VDS), the Pegasus meta-scheduler system, and the Globus toolkit. Probabilistic seismic hazard curves for spectral acceleration at 3.0 seconds have been produced for eleven sites in the Southern California region, including rock and basin sites. At low ground motion levels, there is little difference between the CyberShake and attenuation relationship curves. At higher ground motion (lower probability) levels, the curves are similar for some sites (downtown LA, I-5/SR-14 interchange) but different for

  12. 3D Nitrogen-Anion-Decorated Nickel Sulfides for Highly Efficient Overall Water Splitting.

    PubMed

    Chen, Pengzuo; Zhou, Tianpei; Zhang, Mengxing; Tong, Yun; Zhong, Chengan; Zhang, Nan; Zhang, Lidong; Wu, Changzheng; Xie, Yi

    2017-08-01

    Developing non-noble-metal electrocatalysts with high activity and low cost for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is of paramount importance for improving the generation of H2 fuel by electrocatalytic water-splitting. This study puts forward a new N-anion-decorated Ni3 S2 material synthesized by a simple one-step calcination route, acting as a superior bifunctional electrocatalyst for the OER/HER for the first time. The introduction of N anions significantly modifies the morphology and electronic structure of Ni3 S2 , bringing high surface active sites exposure, enhanced electrical conductivity, optimal HER Gibbs free-energy (ΔGH* ), and water adsorption energy change (ΔGH2O* ). Remarkably, the obtained N-Ni3 S2 /NF 3D electrode exhibits extremely low overpotentials of 330 and 110 mV to reach a current density of 100 and 10 mA cm(-2) for the OER and HER in 1.0 m KOH, respectively. Moreover, an overall water-splitting device comprising this electrode delivers a current density of 10 mA cm(-2) at a very low cell voltage of 1.48 V. Our finding introduces a new way to design advanced bifunctional catalysts for water splitting. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Retrieval of Vegetation Structural Parameters and 3-D Reconstruction of Forest Canopies Using Ground-Based Echidna® Lidar

    NASA Astrophysics Data System (ADS)

    Strahler, A. H.; Yao, T.; Zhao, F.; Yang, X.; Schaaf, C.; Woodcock, C. E.; Jupp, D. L.; Culvenor, D.; Newnham, G.; Lovell, J.

    2010-12-01

    A ground-based, scanning, near-infrared lidar, the Echidna® validation instrument (EVI), built by CSIRO Australia, retrieves structural parameters of forest stands rapidly and accurately, and by merging multiple scans into a single point cloud, the lidar also provides 3-D stand reconstructions. Echidna lidar technology scans with pulses of light at 1064 nm wavelength and digitizes the full return waveform sufficiently finely to recover and distinguish the differing shapes of return pulses as they are scattered by leaves, trunks, and branches. Deployments in New England in 2007 and the southern Sierra Nevada of California in 2008 tested the ability of the instrument to retrieve mean tree diameter, stem count density (stems/ha), basal area, and above-ground woody biomass from single scans at points beneath the forest canopy. Parameters retrieved from five scans located within six 1-ha stand sites matched manually-measured parameters with values of R2 = 0.94-0.99 in New England and 0.92-0.95 in the Sierra Nevada. Retrieved leaf area index (LAI) values were similar to those of LAI-2000 and hemispherical photography. In New England, an analysis of variance showed that EVI-retrieved values were not significantly different from other methods (power = 0.84 or higher). In the Sierra, R2 = 0.96 and 0.81 for hemispherical photos and LAI-2000, respectively. Foliage profiles, which measure leaf area with canopy height, showed distinctly different shapes for the stands, depending on species composition and age structure. New England stand heights, obtained from foliage profiles, were not significantly different (power = 0.91) from RH100 values observed by LVIS in 2003. Three-dimensional stand reconstruction identifies one or more “hits” along the pulse path coupled with the peak return of each hit expressed as apparent reflectance. Returns are classified as trunk, leaf, or ground returns based on the shape of the return pulse and its location. These data provide a point

  14. ADVANCES IN GROUND WATER SAMPLING PROCEDURES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  15. ADVANCES IN GROUND WATER SAMPLING PROCEDURES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  16. Accuracy Based Generation of Thermodynamic Properties for Light Water in RELAP5-3D

    SciTech Connect

    Cliff B. Davis

    2010-09-01

    RELAP5-3D interpolates to obtain thermodynamic properties for use in its internal calculations. The accuracy of the interpolation was determined for the original steam tables currently used by the code. This accuracy evaluation showed that the original steam tables are generally detailed enough to allow reasonably accurate interpolations in most areas needed for typical analyses of nuclear reactors cooled by light water. However, there were some regions in which the original steam tables were judged to not provide acceptable accurate results. Revised steam tables were created that used a finer thermodynamic mesh between 4 and 21 MPa and 530 and 640 K. The revised steam tables solved most of the problems observed with the original steam tables. The accuracies of the original and revised steam tables were compared throughout the thermodynamic grid.

  17. Acquisition of 3D Ground-Penetrating Radar Data by an Autonomous Multiagent Team to Support In-Situ Resource Utilization

    NASA Astrophysics Data System (ADS)

    Frenzel, Francis

    This dissertation details the design and development of a mobile autonomous platform from which to conduct a 3D ground-penetrating radar survey. The system uses a three-rover multiagent team to perform a site-selection activity during a lunar analog mission. The work took place beginning in 2008 and culminated in a final field test on Mauna Kea in Hawaii. This demonstration of autonomous acquisition of 3D ground-penetrating radar in a space robtic application is promising not only for in-situ resource utilization, but also for the concept of multiagent teaming.

  18. Clusters, molecular layers, and 3D crystals of water on Ni(111)

    SciTech Connect

    Thürmer, Konrad; Nie, Shu; Bartelt, Norman C.; Feibelman, Peter J.

    2014-11-14

    We examined the growth and stability of ice layers on Ni(111) up to ∼7 molecular layers (ML) thick using scanning tunneling microscopy. At low coverage, films were comprised of ∼1 nm wide two-dimensional (2D) clusters. Only above ∼0.5 ML did patches of continuous 2D layers emerge, coexisting with the clusters until the first ML was complete. The structure of the continuous layer is clearly different from that of the 2D clusters. Subsequently, a second molecular layer grew on top of the first. 3D crystallites started to form only after this 2nd ML was complete. 2D clusters re-appeared when thicker films were partially evaporated, implying that these clusters represent the equilibrium configuration at low coverage. Binding energies and image simulations computed with density functional theory suggest that the 2D clusters are partially dissociated and surrounded by H adatoms. The complete 2D layer contains only intact water molecules because of the lack of favorable binding sites for H atoms. We propose molecular structures for the 2D layer that are composed of the same pentagon-heptagon binding motif and water density observed on Pt(111). The similarity of the water structures on Pt and Ni suggests a general prescription for generating low-energy configurations on close-packed metal substrates.

  19. 3-D water vapor field in the atmospheric boundary layer observed with scanning differential absorption lidar

    NASA Astrophysics Data System (ADS)

    Späth, Florian; Behrendt, Andreas; Muppa, Shravan Kumar; Metzendorf, Simon; Riede, Andrea; Wulfmeyer, Volker

    2016-04-01

    High-resolution three-dimensional (3-D) water vapor data of the atmospheric boundary layer (ABL) are required to improve our understanding of land-atmosphere exchange processes. For this purpose, the scanning differential absorption lidar (DIAL) of the University of Hohenheim (UHOH) was developed as well as new analysis tools and visualization methods. The instrument determines 3-D fields of the atmospheric water vapor number density with a temporal resolution of a few seconds and a spatial resolution of up to a few tens of meters. We present three case studies from two field campaigns. In spring 2013, the UHOH DIAL was operated within the scope of the HD(CP)2 Observational Prototype Experiment (HOPE) in western Germany. HD(CP)2 stands for High Definition of Clouds and Precipitation for advancing Climate Prediction and is a German research initiative. Range-height indicator (RHI) scans of the UHOH DIAL show the water vapor heterogeneity within a range of a few kilometers up to an altitude of 2 km and its impact on the formation of clouds at the top of the ABL. The uncertainty of the measured data was assessed for the first time by extending a technique to scanning data, which was formerly applied to vertical time series. Typically, the accuracy of the DIAL measurements is between 0.5 and 0.8 g m-3 (or < 6 %) within the ABL even during daytime. This allows for performing a RHI scan from the surface to an elevation angle of 90° within 10 min. In summer 2014, the UHOH DIAL participated in the Surface Atmosphere Boundary Layer Exchange (SABLE) campaign in southwestern Germany. Conical volume scans were made which reveal multiple water vapor layers in three dimensions. Differences in their heights in different directions can be attributed to different surface elevation. With low-elevation scans in the surface layer, the humidity profiles and gradients can be related to different land cover such as maize, grassland, and forest as well as different surface layer

  20. Validating Air Force Weather Satellite Retrieved 3D Cloud Products against Independent Ground and Space-Based Assets

    NASA Astrophysics Data System (ADS)

    Nobis, T. E.; Conner, M. D.

    2016-12-01

    Air Force Weather (AFW) has documented requirements for global cloud analyses and forecasts to support DoD missions around the world. Cloud analyses are constructed using passive cloud detection algorithms from 17 different near real time satellite sources. The algorithms are run on individual satellite transmissions at native satellite resolution in near real time. These native resolution products are then used to construct an hourly global merge on a 24km grid. AFW has also recently started creation of a time-delayed global cloud reanalysis to produce a `best possible' analysis for climatology and verification purposes. Cloud forecasts include global short-range cloud forecasts created using advection techniques as well as statistically post-processed cloud forecast products derived from various global and regional numerical weather forecast models. The result is a mix of cloud products covering different spatial and temporal resolutions with varying latency requirements. AFW has started to aggressively benchmark the performance of their current capabilities. Cloud information collected from so called `active' sensors on the ground at the DOE-ARM sites and from space by such instruments as CloudSat, CALIPSO and CATS are being utilized to characterize the performance of AFW products derived largely by passive means. The goal is to understand the performance of the 3D cloud analysis and forecast products of today to help shape the requirements and standards for a future Numerical Weather Model driven cloud analysis and forecast system driven by advanced 4DVAR techniques. This presentation will present selected results from these benchmarking efforts and highlight insights and observations between passively and actively derived observations and the impacts of varying spatial and temporal depictions of clouds.

  1. Synthesis and 3D printing of biodegradable polyurethane elastomer by a water-based process for cartilage tissue engineering applications.

    PubMed

    Hung, Kun-Che; Tseng, Ching-Shiow; Hsu, Shan-Hui

    2014-10-01

    Biodegradable materials that can undergo degradation in vivo are commonly employed to manufacture tissue engineering scaffolds, by techniques including the customized 3D printing. Traditional 3D printing methods involve the use of heat, toxic organic solvents, or toxic photoinitiators for fabrication of synthetic scaffolds. So far, there is no investigation on water-based 3D printing for synthetic materials. In this study, the water dispersion of elastic and biodegradable polyurethane (PU) nanoparticles is synthesized, which is further employed to fabricate scaffolds by 3D printing using polyethylene oxide (PEO) as a viscosity enhancer. The surface morphology, degradation rate, and mechanical properties of the water-based 3D-printed PU scaffolds are evaluated and compared with those of polylactic-co-glycolic acid (PLGA) scaffolds made from the solution in organic solvent. These scaffolds are seeded with chondrocytes for evaluation of their potential as cartilage scaffolds. Chondrocytes in 3D-printed PU scaffolds have excellent seeding efficiency, proliferation, and matrix production. Since PU is a category of versatile materials, the aqueous 3D printing process developed in this study is a platform technology that can be used to fabricate devices for biomedical applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Human interactions with ground-water

    USGS Publications Warehouse

    Zaporozec, A.

    1983-01-01

    Ground-Water could be considered as an immense reservoir, from which only a certain amount of water can be withdrawn without affecting the quantity and quality of water. This amount is determined by the characteristics of the environment in which ground-water occurs and by the interactions of ground-water with precipitation, surface water, and people. It should be recognized that quantity and quality of ground-water are intimately related and should be considered accordingly. Quantity refers to usable water and water is usable for any specific purpose only so long as its quality has not deteriorated beyond acceptable limits. Thus an overall quantitative and qualitative management of ground water is inevitable, and its should also involve the uses of ground-water reservoirs for purposes other than water supply. The main objective of ground-water management is to ensure that ground-water resources will be available in appropriate time and in appropriate quantity and quality to meet the most important demands of our society. Traditional, and obvious uses of ground-water are the extraction of water for water supplies (domestic, municipal, agricultural, and industrial) and the natural discharge feeding lakes and maintaining base flow of streams. Not so obvious are the uses of ground-water reservoirs, the very framework within which ground-water occurs and moves, and in which other fluids or materials can be stored. In the last two decades, ground-water reservoirs have been intensively considered for many other purposes than water supplies. Diversified and very often conflicting uses need to be evaluated and dealt with in the most efficient way in order to determine the importance of each possible use, and to assign priorities of these uses. With rising competition for the use of ground-water reservoirs, we will also need to increase the potential for effective planning of ground-water development and protection. Man's development and use of ground-water necessarily

  3. Ground Water Rule - Boil Water Advisory - Public Notification Template

    EPA Pesticide Factsheets

    The Ground Water Rule - Boil Water Advisory - Public Notification Template can be use to issue a Tier 1 Public Notification when it has been determined that source ground water is contaminated with E. Coli bacteria.

  4. Sustainability of ground-water resources

    USGS Publications Warehouse

    Alley, William M.; Reilly, Thomas E.; Franke, O. Lehn

    1999-01-01

    The pumpage of fresh ground water in the United States in 1995 was estimated to be approximately 77 billion gallons per day (Solley and others, 1998), which is about 8 percent of the estimated 1 trillion gallons per day of natural recharge to the Nation's ground-water systems (Nace, 1960). From an overall national perspective, the ground-water resource appears ample. Locally, however, the availability of ground water varies widely. Moreover, only a part of the ground water stored in the subsurface can be recovered by wells in an economic manner and without adverse consequences.

  5. Quasi 3D modelling of water flow in the sandy soil

    NASA Astrophysics Data System (ADS)

    Rezaei, Meisam; Seuntjens, Piet; Joris, Ingeborg; Boënne, Wesley; De Pue, Jan; Cornelis, Wim

    2016-04-01

    Monitoring and modeling tools may improve irrigation strategies in precision agriculture. Spatial interpolation is required for analyzing the effects of soil hydraulic parameters, soil layer thickness and groundwater level on irrigation management using hydrological models at field scale. We used non-invasive soil sensor, a crop growth (LINGRA-N) and a soil hydrological model (Hydrus-1D) to predict soil-water content fluctuations and crop yield in a heterogeneous sandy grassland soil under supplementary irrigation. In the first step, the sensitivity of the soil hydrological model to hydraulic parameters, water stress, crop yield and lower boundary conditions was assessed after integrating models at one soil column. Free drainage and incremental constant head conditions were implemented in a lower boundary sensitivity analysis. In the second step, to predict Ks over the whole field, the spatial distributions of Ks and its relationship between co-located soil ECa measured by a DUALEM-21S sensor were investigated. Measured groundwater levels and soil layer thickness were interpolated using ordinary point kriging (OK) to a 0.5 by 0.5 m in aim of digital elevation maps. In the third step, a quasi 3D modelling approach was conducted using interpolated data as input hydraulic parameter, geometric information and boundary conditions in the integrated model. In addition, three different irrigation scenarios namely current, no irrigation and optimized irrigations were carried out to find out the most efficient irrigation regime. In this approach, detailed field scale maps of soil water stress, water storage and crop yield were produced at each specific time interval to evaluate the best and most efficient distribution of water using standard gun sprinkler irrigation. The results show that the effect of the position of the groundwater level was dominant in soil-water content prediction and associated water stress. A time-dependent sensitivity analysis of the hydraulic

  6. Chemical contamination of ground water in India

    SciTech Connect

    Mohapatra, S.P.; Agnihoiri, N.P.

    1996-10-01

    Ground water is the main source of drinking water in rural areas and many urban areas in India. In addition, it has been increasingly used for irrigation in farmland. Contamination of ground water by persistent inorganic and organic chemicals has emerged as a major environmental concern in recent years. Nitrate, fluoride, heavy metals and organochlorine compounds are found to be major contaminants of ground water in different parts of the country. At many places the concentrations of these chemicals exceed national and international guideline values for drinking water. While large concentrations of heavy metals come from industrial sources, agricultural activities are responsible for ground water contamination by nitrate and organochlorine insecticides.

  7. 3D soil water nowcasting using electromagnetic conductivity imaging and the ensemble Kalman filter

    NASA Astrophysics Data System (ADS)

    Huang, Jingyi; McBratney, Alex; Minasny, Budiman; Triantafilis, John

    2017-04-01

    Mapping and immediate forecasting of soil water content (θ) and its movement can be challenging. Although apparent electrical conductivity (ECa) measured by electromagnetic induction has been used, it is difficult to apply it along a transect or across a field. Across a 3.95-ha field with varying soil texture, an ensemble Kalman filter (EnFK) was used to monitor and nowcast θ dynamics in 2-d and 3-d over 16 days. The EnKF combined a physical model fitted with θ measured by soil moisture sensors and an Artificial Neural Network model comprising estimate of true electrical conductivity (σ) generated by inversions of DUALEM-421S ECa data. Results showed that the spatio-temporal variation in θ can be successfully modelled using the EnKF (Lin's concordance = 0.89). Soil water dried fast at the beginning of the irrigation and decreased with time and soil depth, which were consistent with the classical soil drying theory and experiments. It was also found that the soil dried fast in the loamy and duplex soils across the field, which was attributable to deep drainage and preferential flows. It was concluded that the EnKF approach can be used to better the irrigation practice so that variation in irrigation is minimised and irrigation efficiency is improved by applying variable rates of irrigation across the field. In addition, soil water status can be nowcasted using this method with weather forecast information, which will provide guidance to farmers for real-time irrigation management.

  8. 3D soil water nowcasting using electromagnetic conductivity imaging and the ensemble Kalman filter

    NASA Astrophysics Data System (ADS)

    Huang, Jingyi; McBratney, Alex B.; Minasny, Budiman; Triantafilis, John

    2017-06-01

    Mapping and immediate forecasting of soil water content (θ) and its movement can be challenging. Although inversion of apparent electrical conductivity (ECa) measured by electromagnetic induction to calculate depth-specific electrical conductivity (σ) has been used, it is difficult to apply it across a field. In this paper we use a calibration established along a transect, across a 3.94-ha field with varying soil texture, using an ensemble Kalman filter (EnKF) to monitor and nowcast the 3-dimensional θ dynamics on 16 separate days over a period of 38 days. The EnKF combined a physical model fitted with θ measured by soil moisture sensors and an Artificial Neural Network model comprising σ generated by quasi-3d inversions of DUALEM-421S ECa data. Results showed that the distribution of θ was controlled by soil texture, topography, and vegetation. Soil water dried fastest at the beginning after the initial irrigation event and decreased with time and soil depth, which was consistent with classical soil drying theory and experiments. It was also found that the soil dried fastest in the loamy and duplex soils present in the field, which was attributable to deep drainage and preferential flow. It was concluded that the EnKF approach can be used to improve the irrigation efficiency by applying variable irrigation rates across the field. In addition, soil water status can be nowcasted across large spatial extents using this method with weather forecast information, which will provide guidance to farmers for real-time irrigation management.

  9. Improving organic tandem solar cells based on water-processed nanoparticles by quantitative 3D nanoimaging.

    PubMed

    Pedersen, E B L; Angmo, D; Dam, H F; Thydén, K T S; Andersen, T R; Skjønsfjell, E T B; Krebs, F C; Holler, M; Diaz, A; Guizar-Sicairos, M; Breiby, D W; Andreasen, J W

    2015-08-28

    Organic solar cells have great potential for upscaling due to roll-to-roll processing and a low energy payback time, making them an attractive sustainable energy source for the future. Active layers coated with water-dispersible Landfester particles enable greater control of the layer formation and easier access to the printing industry, which has reduced the use of organic solvents since the 1980s. Through ptychographic X-ray computed tomography (PXCT), we image quantitatively a roll-to-roll coated photovoltaic tandem stack consisting of one bulk heterojunction active layer and one Landfester particle active layer. We extract the layered morphology with structural and density information including the porosity present in the various layers and the silver electrode with high resolution in 3D. The Landfester particle layer is found to have an undesired morphology with negatively correlated top- and bottom interfaces, wide thickness distribution and only partial surface coverage causing electric short circuits through the layer. By top coating a polymer material onto the Landfester nanoparticles we eliminate the structural defects of the layer such as porosity and roughness, and achieve the increased performance larger than 1 V expected for a tandem cell. This study highlights that quantitative imaging of weakly scattering stacked layers of organic materials has become feasible by PXCT, and that this information cannot be obtained by other methods. In the present study, this technique specifically reveals the need to improve the coatability and layer formation of Landfester nanoparticles, thus allowing improved solar cells to be produced.

  10. Automated 3-D Printed Arrays to Evaluate Genotoxic Chemistry: E-Cigarettes and Water Samples.

    PubMed

    Kadimisetty, Karteek; Malla, Spundana; Rusling, James F

    2017-05-26

    A novel, automated, low cost, three-dimensional (3-D) printed microfluidic array was developed to detect DNA damage from metabolites of chemicals in environmental samples. The electrochemiluminescent (ECL) detection platform incorporates layer-by-layer (LbL) assembled films of microsomal enzymes, DNA and an ECL-emitting ruthenium metallopolymer in ∼10 nm deep microwells. Liquid samples are introduced into the array, metabolized by the human enzymes, products react with DNA if possible, and DNA damage is detected by ECL with a camera. Measurements of relative DNA damage by the array assess the genotoxic potential of the samples. The array analyzes three samples simultaneously in 5 min. Measurement of cigarette and e-cigarette smoke extracts and polluted water samples was used to establish proof of concept. Potentially genotoxic reactions from e-cigarette vapor similar to smoke from conventional cigarettes were demonstrated. Untreated wastewater showed a high genotoxic potential compared to negligible values for treated wastewater from a pollution control treatment plant. Reactivity of chemicals known to produce high rates of metabolite-related DNA damage were measured, and array results for environmental samples were expressed in terms of equivalent responses from these standards to assess severity of possible DNA damage. Genotoxic assessment of wastewater samples during processing also highlighted future on-site monitoring applications.

  11. International borders, ground water flow, and hydroschizophrenia.

    PubMed

    Jarvis, Todd; Giordano, Mark; Puri, Shammy; Matsumoto, Kyoko; Wolf, Aaron

    2005-01-01

    A substantial body of research has been conducted on transboundary water, transboundary water law, and the mitigation of transboundary water conflict. However, most of this work has focused primarily on surface water supplies. While it is well understood that aquifers cross international boundaries and that the base flow of international river systems is often derived in part from ground water, transboundary ground water and surface water systems are usually managed under different regimes, resulting in what has been described as "hydroschizophrenia." Adding to the problem, the hydrologic relationships between surface and ground water supplies are only known at a reconnaissance level in even the most studied international basins, and thus even basic questions regarding the territorial sovereignty of ground water resources often remain unaddressed or even unasked. Despite the tensions inherent in the international setting, riparian nations have shown tremendous creativity in approaching regional development, often through preventive diplomacy, and the creation of "baskets of benefits," which allow for positive-sum, integrative allocations of joint gains. In contrast to the notion of imminent water wars, the history of hydropolitical relations worldwide has been overwhelmingly cooperative. Limited ground water management in the international arena, coupled with the fact that few states or countries regulate the use of ground water, begs the question: will international borders serve as boundaries for increased "flows" of hydrologic information and communication to maintain strategic aquifers, or will increased competition for shared ground water resources lead to the potential loss of strategic aquifers and "no flows" for both ground water users?

  12. In situ growth rates of deep-water octocorals determined from 3D photogrammetric reconstructions

    NASA Astrophysics Data System (ADS)

    Bennecke, Swaantje; Kwasnitschka, Tom; Metaxas, Anna; Dullo, Wolf-Christian

    2016-12-01

    Growth rates of deep-water corals provide important information on the recovery potential of these ecosystems, for example from fisheries-induced impacts. Here, we present in situ growth dynamics that are currently largely unknown for deep-water octocorals, calculated by applying a non-destructive method. Videos of a boulder harbouring multiple colonies of Paragorgia arborea and Primnoa resedaeformis in the Northeast Channel Coral Conservation Area at the entrance to the Gulf of Maine at 863 m depth were collected in 2006, 2010 and 2014. Photogrammetric reconstructions of the boulder and the fauna yielded georeferenced 3D models for all sampling years. Repeated measurements of total length and cross-sectional area of the same colonies allowed the observation of growth dynamics. Growth rates of total length of Paragorgia arborea decreased over time with higher rates between 2006 and 2010 than between 2010 and 2014, while growth rates of cross-sectional area remained comparatively constant. A general trend of decreasing growth rates of total length with size of the coral colony was documented. While no growth was observed for the largest colony (165 cm in length) between 2010 and 2014, a colony 50-65 cm in length grew 3.7 cm yr-1 between 2006 and 2010. Minimum growth rates of 1.6-2.7 cm yr-1 were estimated for two recruits (<23 cm in 2014) of Primnoa resedaeformis. We successfully extracted biologically meaningful data from photogrammetric models and present the first in situ growth rates for these coral species in the Northwest Atlantic.

  13. Finite Element Methods and Multiphase Continuum Theory for Modeling 3D Air-Water-Sediment Interactions

    NASA Astrophysics Data System (ADS)

    Kees, C. E.; Miller, C. T.; Dimakopoulos, A.; Farthing, M.

    2016-12-01

    The last decade has seen an expansion in the development and application of 3D free surface flow models in the context of environmental simulation. These models are based primarily on the combination of effective algorithms, namely level set and volume-of-fluid methods, with high-performance, parallel computing. These models are still computationally expensive and suitable primarily when high-fidelity modeling near structures is required. While most research on algorithms and implementations has been conducted in the context of finite volume methods, recent work has extended a class of level set schemes to finite element methods on unstructured methods. This work considers models of three-phase flow in domains containing air, water, and granular phases. These multi-phase continuum mechanical formulations show great promise for applications such as analysis of coastal and riverine structures. This work will consider formulations proposed in the literature over the last decade as well as new formulations derived using the thermodynamically constrained averaging theory, an approach to deriving and closing macroscale continuum models for multi-phase and multi-component processes. The target applications require the ability to simulate wave breaking and structure over-topping, particularly fully three-dimensional, non-hydrostatic flows that drive these phenomena. A conservative level set scheme suitable for higher-order finite element methods is used to describe the air/water phase interaction. The interaction of these air/water flows with granular materials, such as sand and rubble, must also be modeled. The range of granular media dynamics targeted including flow and wave transmision through the solid media as well as erosion and deposition of granular media and moving bed dynamics. For the granular phase we consider volume- and time-averaged continuum mechanical formulations that are discretized with the finite element method and coupled to the underlying air/water

  14. Fracture control of ground water flow and water chemistry in a rock aquitard

    USGS Publications Warehouse

    Eaton, T.T.; Anderson, M.P.; Bradbury, K.R.

    2007-01-01

    There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/Ss) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies. ?? 2007 National Ground Water Association.

  15. Diamond in 3-D

    NASA Image and Video Library

    2004-08-20

    This 3-D, microscopic imager mosaic of a target area on a rock called Diamond Jenness was taken after NASA Mars Exploration Rover Opportunity ground into the surface with its rock abrasion tool for a second time. 3D glasses are necessary.

  16. Ground water near Newton, Jasper County, Iowa

    USGS Publications Warehouse

    Buchmiller, Robert C.

    2001-01-01

    The water quality in the South Skunk River and the alluvial aquifer was similar, except most ground-water samples contained low dissolved oxygen concentrations. The low dissolved-oxygen concentrations in ground water resulted in high concentrations of iron and manganese in some locations and reduced forms of nitrogen.

  17. Mississippi Embayment Regional Ground Water Study

    EPA Science Inventory

    Increased water usage in the southeastern United States in the tri-state area of Tennessee, Mississippi and Arkansas poses a dilemma to ensuring long-term sustainability of the quantity and quality of ground-water resources that underlie the region. Demand for ground water by ag...

  18. Mississippi Embayment Regional Ground Water Study

    EPA Science Inventory

    Increased water usage in the southeastern United States in the tri-state area of Tennessee, Mississippi and Arkansas poses a dilemma to ensuring long-term sustainability of the quantity and quality of ground-water resources that underlie the region. Demand for ground water by ag...

  19. Ground water resources of Lee County

    USGS Publications Warehouse

    Gordon, Donivan L.

    1980-01-01

    In terms of these factors, there are few locations in Lee County where the availability of ground water is not limited to some degree. The most common limitation is poor water quality, that is, highly mineralized ground water. Secondary limitations are generally related to poor distribution, small yields from some sources, and poor accessibility due to the great depths to adequate sources.

  20. Guide to Louisiana's ground-water resources

    USGS Publications Warehouse

    Stuart, C.G.; Knochenmus, D.D.; McGee, B.D.

    1994-01-01

    Ground water is one of the most valuable and abundant natural resources of Louisiana. Of the 4-.4 million people who live in the State, 61 percent use ground water as a source for drinking water. Most industrial and rural users and half of the irrigation users in the State rely on ground water. Quantity, however, is not the only aspect that makes ground water so valuable; quality also is important for its use. In most areas, little or no water treatment is required for drinking water and industrial purposes. Knowledge of Louisiana's ground-water resources is needed to ensure proper development and protection of this valuable resource. This report is designed to inform citizens about the availability and quality of ground water in Louisiana. It is not intended as a technical reference; rather, it is a guide to ground water and the significant role this resource plays in the state. Most of the ground water that is used in the State is withdrawn from 13 aquifers and aquifer systems: the Cockfield, Sparta, and Carrizo-Wilcox aquifersin northern Louisiana; Chicot aquifer system, Evangeline aquifer, Jasper aquifer system, and Catahoula aquifer in central and southwestern Louisiana; the Chicot equivalent, Evangeline equivalent, and Jasper equivalent aquifer systems in southeastern Louisiana; and the MississippiRiver alluvial, Red River alluvial, and upland terrace aquifers that are statewide. Ground water is affected by man's activities on the land surface, and the major ground-water concerns in Louisiana are: (1) contamination from surface disposal of hazardous waste, agricultural chemicals, and petroleum products; (2) contamination from surface wastes and saltwater through abandoned wells; (3) saltwater encroachment; and (4) local overdevelopment. Information about ground water in Louisiana is extensive and available to the public. Several State and Federal agencies provide published and unpublished material upon request.

  1. Ground Water in the Anchorage Area, Alaska--Meeting the Challenges of Ground-Water Sustainability

    USGS Publications Warehouse

    Moran, Edward H.; Galloway, Devin L.

    2006-01-01

    Ground water is an important component of Anchorage's water supply. During the 1970s and early 80s when ground water extracted from aquifers near Ship Creek was the principal source of supply, area-wide declines in ground-water levels resulted in near record low streamflows in Ship Creek. Since the importation of Eklutna Lake water in the late 1980s, ground-water use has been reduced and ground water has contributed 14-30 percent of the annual supply. As Anchorage grows, given the current constraints on the Eklutna Lake water availability, the increasing demand for water could place an increasing reliance on local ground-water resources. The sustainability of Anchorage's ground-water resources challenges stakeholders to develop a comprehensive water-resources management strategy.

  2. Improving organic tandem solar cells based on water-processed nanoparticles by quantitative 3D nanoimaging

    NASA Astrophysics Data System (ADS)

    Pedersen, E. B. L.; Angmo, D.; Dam, H. F.; Thydén, K. T. S.; Andersen, T. R.; Skjønsfjell, E. T. B.; Krebs, F. C.; Holler, M.; Diaz, A.; Guizar-Sicairos, M.; Breiby, D. W.; Andreasen, J. W.

    2015-08-01

    Organic solar cells have great potential for upscaling due to roll-to-roll processing and a low energy payback time, making them an attractive sustainable energy source for the future. Active layers coated with water-dispersible Landfester particles enable greater control of the layer formation and easier access to the printing industry, which has reduced the use of organic solvents since the 1980s. Through ptychographic X-ray computed tomography (PXCT), we image quantitatively a roll-to-roll coated photovoltaic tandem stack consisting of one bulk heterojunction active layer and one Landfester particle active layer. We extract the layered morphology with structural and density information including the porosity present in the various layers and the silver electrode with high resolution in 3D. The Landfester particle layer is found to have an undesired morphology with negatively correlated top- and bottom interfaces, wide thickness distribution and only partial surface coverage causing electric short circuits through the layer. By top coating a polymer material onto the Landfester nanoparticles we eliminate the structural defects of the layer such as porosity and roughness, and achieve the increased performance larger than 1 V expected for a tandem cell. This study highlights that quantitative imaging of weakly scattering stacked layers of organic materials has become feasible by PXCT, and that this information cannot be obtained by other methods. In the present study, this technique specifically reveals the need to improve the coatability and layer formation of Landfester nanoparticles, thus allowing improved solar cells to be produced.Organic solar cells have great potential for upscaling due to roll-to-roll processing and a low energy payback time, making them an attractive sustainable energy source for the future. Active layers coated with water-dispersible Landfester particles enable greater control of the layer formation and easier access to the printing

  3. 3D leaf water content mapping using terrestrial laser scanner backscatter intensity with radiometric correction

    NASA Astrophysics Data System (ADS)

    Zhu, Xi; Wang, Tiejun; Darvishzadeh, Roshanak; Skidmore, Andrew K.; Niemann, K. Olaf

    2015-12-01

    Leaf water content (LWC) plays an important role in agriculture and forestry management. It can be used to assess drought conditions and wildfire susceptibility. Terrestrial laser scanner (TLS) data have been widely used in forested environments for retrieving geometrically-based biophysical parameters. Recent studies have also shown the potential of using radiometric information (backscatter intensity) for estimating LWC. However, the usefulness of backscatter intensity data has been limited by leaf surface characteristics, and incidence angle effects. To explore the idea of using LiDAR intensity data to assess LWC we normalized (for both angular effects and leaf surface properties) shortwave infrared TLS data (1550 nm). A reflectance model describing both diffuse and specular reflectance was applied to remove strong specular backscatter intensity at a perpendicular angle. Leaves with different surface properties were collected from eight broadleaf plant species for modeling the relationship between LWC and backscatter intensity. Reference reflectors (Spectralon from Labsphere, Inc.) were used to build a look-up table to compensate for incidence angle effects. Results showed that before removing the specular influences, there was no significant correlation (R2 = 0.01, P > 0.05) between the backscatter intensity at a perpendicular angle and LWC. After the removal of the specular influences, a significant correlation emerged (R2 = 0.74, P < 0.05). The agreement between measured and TLS-derived LWC demonstrated a significant reduction of RMSE (root mean square error, from 0.008 to 0.003 g/cm2) after correcting for the incidence angle effect. We show that it is possible to use TLS to estimate LWC for selected broadleaved plants with an R2 of 0.76 (significance level α = 0.05) at leaf level. Further investigations of leaf surface and internal structure will likely result in improvements of 3D LWC mapping for studying physiology and ecology in vegetation.

  4. 3D numerical simulations of dense water cascading in an idealised laboratory setting

    NASA Astrophysics Data System (ADS)

    Wobus, F.; Shapiro, G. I.; Maqueda, M. A. M.; Huthnance, J. M.

    2012-04-01

    The sinking of dense waters flowing from shelf seas down the continental slope "cascading" contributes to ocean ventilation and water mass formation (notably in the Antarctic) and hence ocean circulation. It is also deemed to affect carbon cycling by providing an efficient mechanism of export of carbon-rich surface waters to a greater depth thus contributing to the "carbon pump". Cascading occurs where dense water - formed by cooling, evaporation or ice-formation with brine rejection over the shallow continental shelf - spills over the shelf edge and descends the continental slope as a near-bottom gravity current. During its descent, the plume is modified by mixing and entrainment, and detaches off the slope when reaching its neutral buoyancy level. Cascading over steep bottom topography is studied here in numerical experiments using POLCOMS, a 3D ocean circulation model which utilizes a terrain-following s-coordinate system (Wobus et al, 2011). The model setup is based on a previously conducted (Shapiro and Zatsepin, 1997) laboratory experiment of a continuous dense water flow from a central source on a conical slope in a rotating tank. The governing parameters of the experiments are the density difference between plume and ambient water, the flow rate, the speed of rotation and (in the model) diffusivity and viscosity. The descent of the dense flow as characterised by the length of the plume as a function of time is studied for a range of physical and model parameters. Very good agreement between the model and the laboratory results is shown in dimensional and non-dimensional variables. It is confirmed that a hydrostatic model is capable of reproducing the essential physics of cascading on a very steep slope if the model correctly resolves velocity veering in the bottom boundary layer. Experiments changing the height of the bottom Ekman layer (by changing viscosity) and modifying the plume from a 2-layer system to a stratified regime (by enhancing diapycnal

  5. Ground-water data for Michigan 1985

    USGS Publications Warehouse

    Huffman, G.C.

    1986-01-01

    Water levels, locations, depths, and aquifers tapped are given for 113 observation wells. Tabulated data include extremes of water levels for calendar year 1985 and for the period of record, pumpage of most major ground-water users in the State, and water-quality data from selected wells. The largest reported user of ground-water, the city of Lansing, pumped 7.9 billion gallons from the Saginaw Formation and glacial deposits in 1985.

  6. Ground-water data for Michigan 1989

    USGS Publications Warehouse

    Huffman, G.C.; Whited, C.R.

    1991-01-01

    Water levels, locations, depths, and aquifers tapped are given for 108 observation wells. Tabulated data include a listing of ground-water reports in Michigan, extremes of water levels for calendar year 1989 and for the period of record, pumpage of most major ground-water users in the State, and water-quality data from selected wells. In 1989, the two largest municipal users of ground water were Lansing and Kalamazoo. Lansing pumped 7.2 billion gallons from the Saginaw Formation and glacial deposits; Kalamazoo pumped 6.7 billion gallons from glacial deposits only.

  7. Ground-water data for Michigan 1990

    USGS Publications Warehouse

    Huffman, G.C.; Whited, C.R.

    1993-01-01

    Water levels, locations, depths, and aquifers tapped are given for 107 observation wells. Tabulated data include a listing of ground-water reports in Michigan, extremes of water levels for calendar year 1990 and for the period of record, pumpage of most major ground-water users in the State, and a map showing previous collected water-quality data from selected wells. In 1990, the two largest municipal users of ground water were Lansing and Kalamazoo. Lansing pumped 7.2 billion gallons from the Saginaw Formation and glacial deposits; Kalamazoo pumped 7.0 billion gallons from glacial deposits only.

  8. Ground-water data for Michigan 1988

    USGS Publications Warehouse

    Huffman, G.C.; Whited, C.R.

    1989-01-01

    Water levels, locations, depths, and aquifers tapped are given for 112 observation wells. Tabulated data include a listing of ground water reports in Michigan, extremes of water levels for calendar year 1988 and for the period of record, pumpage of most major ground-water users in the State, and water-quality data from selected wells. The two largest municipal users of ground water, were the cities of Lansing and Kalamazoo. In 1988, Lansing pumped 7.8 billion gallons from the Saginaw Formation and glacial deposits and Kalamazoo pumped 7.4 billion gallons from glacial deposits only.

  9. Ground water flow in a desert basin: challenges of simulating transport of dissolved chromium.

    PubMed

    Andrews, Charles B; Neville, Christopher J

    2003-01-01

    A large chromium plume that evolved from chromium releases in a valley near the Mojave River was studied to understand the processes controlling fate and migration of chromium in ground water and used as a tracer to study the dynamics of a basin and range ground water system. The valley that was studied is naturally arid with high evapotranspiration such that essentially no precipitation infiltrates to the water table. The dominant natural hydrogeologic processes are recharge to the ground water system from the Mojave River during the infrequent episodes when there is flow in the river, and ground water flow toward a playa lake where the ground water evaporates. Agricultural pumping in the valley from the mid-1930s to the 1970s significantly altered ground water flow conditions by decreasing water levels in the valley by more than 20 m. This pumping declined significantly as a result of dewatering of the aquifer, and water levels have since recovered modestly. The ground water system was modeled using MODFLOW, and chromium transport was simulated using MT3D. Several innovative modifications were made to these modeling programs to simulate important processes in this ground water system. Modifications to MODFLOW include developing a new well package that estimates pumping rates from irrigation wells at each time step based on available drawdown. MT3D was modified to account for mass trapped above the water table when the water table declines beneath nonirrigated areas and to redistribute mass to the system when water levels rise.

  10. 3D modeling of gas/water distribution in water-bearing carbonate gas reservoirs: the Longwangmiao gas field, China

    NASA Astrophysics Data System (ADS)

    Ou, Chenghua; Li, ChaoChun; Ma, Zhonggao

    2016-10-01

    A water-bearing carbonate gas reservoir is an important natural gas resource being developed worldwide. Due to the long-term water/rock/gas interaction during geological evolution, complex gas/water distribution has formed under the superposed effect of sedimentary facies, reservoir space facies and gravity difference of fluid facies. In view of these challenges, on the basis of the conventional three-stage modeling method, this paper presents a modelling method controlled by four-stage facies to develop 3D model of a water-bearing carbonate gas reservoir. Key to this method is the reservoir property modelling controlled by two-stage facies, and the fluid property modelling controlled by another two-stage facies. The prerequisite of this method is a reliable database obtained from solid geological investigation. On the basis of illustrating the principles of the modelling method controlled by four-stage facies, this paper further implements systematically modeling of the heterogeneous gas/water distribution of the Longwangmiao carbonate formation in the Moxi-Gaoshiti area, Sichuan basin, China.

  11. Application of Technical Measures and Software in Constructing Photorealistic 3D Models of Historical Building Using Ground-Based and Aerial (UAV) Digital Images

    NASA Astrophysics Data System (ADS)

    Zarnowski, Aleksander; Banaszek, Anna; Banaszek, Sebastian

    2015-12-01

    Preparing digital documentation of historical buildings is a form of protecting cultural heritage. Recently there have been several intensive studies using non-metric digital images to construct realistic 3D models of historical buildings. Increasingly often, non-metric digital images are obtained with unmanned aerial vehicles (UAV). Technologies and methods of UAV flights are quite different from traditional photogrammetric approaches. The lack of technical guidelines for using drones inhibits the process of implementing new methods of data acquisition. This paper presents the results of experiments in the use of digital images in the construction of photo-realistic 3D model of a historical building (Raphaelsohns' Sawmill in Olsztyn). The aim of the study at the first stage was to determine the meteorological and technical conditions for the acquisition of aerial and ground-based photographs. At the next stage, the technology of 3D modelling was developed using only ground-based or only aerial non-metric digital images. At the last stage of the study, an experiment was conducted to assess the possibility of 3D modelling with the comprehensive use of aerial (UAV) and ground-based digital photographs in terms of their labour intensity and precision of development. Data integration and automatic photo-realistic 3D construction of the models was done with Pix4Dmapper and Agisoft PhotoScan software Analyses have shown that when certain parameters established in an experiment are kept, the process of developing the stock-taking documentation for a historical building moves from the standards of analogue to digital technology with considerably reduced cost.

  12. GROUND WATER CONTAMINATION POTENTIAL FROM STORMWATER INFILTRATION

    EPA Science Inventory

    Prior to urbanization, ground water recharge resulted from infiltration of precipitation through pervious surfaces, including grasslands and woods. This infiltration water was relatively uncontaminated. With urbanization, the permeable soil surface area through which recharge by...

  13. GROUND WATER CONTAMINATION POTENTIAL FROM STORMWATER INFILTRATION

    EPA Science Inventory

    Prior to urbanization, ground water recharge resulted from infiltration of precipitation through pervious surfaces, including grasslands and woods. This infiltration water was relatively uncontaminated. With urbanization, the permeable soil surface area through which recharge by...

  14. Ground water currents: Developments in innovative ground water treatment, June 1994

    SciTech Connect

    Not Available

    1994-06-01

    ;Contents: Low-level uranium removed from ground water; Promising ion exchange technology seeks site for demonstration; Pervaporation membrane removes volatile organic compounds (VOCs); and Ground water sampling information available.

  15. Ground-water quality in Wyoming

    USGS Publications Warehouse

    Larson, L.R.

    1984-01-01

    This report graphically summarizes ground-water quality from selected chemical-quality data for about 2,300 ground-water sites in Wyoming. Dissolved-solids, nitrate, fluoride, arsenic, barium, cadmium, chromium, lead, mercury, selenium, iron, and manganese concentrations are summarized on a statewide basis. The major chemical-quality problem that limits the use of Wyoming ground-water is excessive dissolved-solids concentrations. The aquifers with the best quality water, based on the lowest median dissolved-solids concentration of water in aquifers with 20 or more sampled sites, are Holocene lacustrine deposits, the upper Testiary Ogallala Formation and Arikaree Formation, and the Mississippian Madison Limestone. The counties with the best quality water, based on the lowest median dissolved-solids concentrations are Teton County and Laramie County. Hot Springs County and Natrona County have the highest median dissolved-solids concentrations. About 3 percent of the nitrate concentrations of ground-water samples exceeded the national primary drinking-water standard of 10 milligrams per liter. Fluoride concentrations exceeded the national primary drinking-water standard in 14 percent of the ground-water samples. Except for selenium, toxic trace elements generally have not been found in concentrations in excess of the drinking-water standards. About 19 percent of the iron and about 30 percent of the manganese concentrations in ground-water samples exceeded the national secondary drinking-water standards. (USGS)

  16. 3D WO3 /BiVO4 /Cobalt Phosphate Composites Inverse Opal Photoanode for Efficient Photoelectrochemical Water Splitting.

    PubMed

    Zhang, Haifeng; Zhou, Weiwei; Yang, Yaping; Cheng, Chuanwei

    2017-04-01

    A novel 3D WO3 /BiVO4 /cobalt phosphate composite inverse opal is designed for photoeletrochemical (PEC) water splitting, yielding a significantly improved PEC performance. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Ground-water data for Michigan 1983

    USGS Publications Warehouse

    Huffman, G.C.

    1984-01-01

    Water levels, locations, depths, and aquifers tapped are given for 115 observation wells. Tabulated data include extremes of water levels for 1983 and for the period of record, pumpage of most major ground-water users in the State, and quality data on selected wells. The largest reported user of ground-water, the city of Lansing, pumped 8.1 billion gallons from the Saginaw Formation and glacial deposits.

  18. Ground-water data for Michigan 1982

    USGS Publications Warehouse

    Huffman, G.C.

    1983-01-01

    Water levels, locations, depths, and aquifers tapped are given for 117 observation wells. Tabulated data include extremes of water levels for 1982 and for the period of record, pumpage of most major ground-water users in the State, and quality data on selected wells. The largest reported user of ground-water, the city of Lansing, pumped 8.2 billion gallons from the Saginaw Formation and glacial deposits.

  19. Ground and Aerial Digital Documentation of Cultural Heritage: Providing Tools for 3d Exploitation of Archaeological Data

    NASA Astrophysics Data System (ADS)

    Cantoro, G.

    2017-02-01

    Archaeology is by its nature strictly connected with the physical landscape and as such it explores the inter-relations of individuals with places in which they leave and the nature that surrounds them. Since its earliest stages, archaeology demonstrated its permeability to scientific methods and innovative techniques or technologies. Archaeologists were indeed between the first to adopt GIS platforms (since already almost three decades) on large scale and are now between the most demanding customers for emerging technologies such as digital photogrammetry and drone-aided aerial photography. This paper aims at presenting case studies where the "3D approach" can be critically analysed and compared with more traditional means of documentation. Spot-light is directed towards the benefits of a specifically designed platform for user to access the 3D point-clouds and explore their characteristics. Beside simple measuring and editing tools, models are presented in their actual context and location, with historical and archaeological information provided on the side. As final step of a parallel project on geo-referencing and making available a large archive of aerial photographs, 3D models derived from photogrammetric processing of images have been uploaded and linked to photo-footprints polygons. Of great importance in such context is the possibility to interchange the point-cloud colours with satellite imagery from OpenLayers. This approach makes it possible to explore different landscape configurations due to time-changes with simple clicks. In these cases, photogrammetry or 3D laser scanning replaced, sided or integrated legacy documentation, creating at once a new set of information for forthcoming research and ideally new discoveries.

  20. Feasibility of RACT for 3D dose measurement and range verification in a water phantom

    SciTech Connect

    Alsanea, Fahed; Moskvin, Vadim; Stantz, Keith M.

    2015-02-15

    Purpose: The objective of this study is to establish the feasibility of using radiation-induced acoustics to measure the range and Bragg peak dose from a pulsed proton beam. Simulation studies implementing a prototype scanner design based on computed tomographic methods were performed to investigate the sensitivity to proton range and integral dose. Methods: Derived from thermodynamic wave equation, the pressure signals generated from the dose deposited from a pulsed proton beam with a 1 cm lateral beam width and a range of 16, 20, and 27 cm in water using Monte Carlo methods were simulated. The resulting dosimetric images were reconstructed implementing a 3D filtered backprojection algorithm and the pressure signals acquired from a 71-transducer array with a cylindrical geometry (30 × 40 cm) rotated over 2π about its central axis. Dependencies on the detector bandwidth and proton beam pulse width were performed, after which, different noise levels were added to the detector signals (using 1 μs pulse width and a 0.5 MHz cutoff frequency/hydrophone) to investigate the statistical and systematic errors in the proton range (at 20 cm) and Bragg peak dose (of 1 cGy). Results: The reconstructed radioacoustic computed tomographic image intensity was shown to be linearly correlated to the dose within the Bragg peak. And, based on noise dependent studies, a detector sensitivity of 38 mPa was necessary to determine the proton range to within 1.0 mm (full-width at half-maximum) (systematic error < 150 μm) for a 1 cGy Bragg peak dose, where the integral dose within the Bragg peak was measured to within 2%. For existing hydrophone detector sensitivities, a Bragg peak dose of 1.6 cGy is possible. Conclusions: This study demonstrates that computed tomographic scanner based on ionizing radiation-induced acoustics can be used to verify dose distribution and proton range with centi-Gray sensitivity. Realizing this technology into the clinic has the potential to significantly

  1. FUNDAMENTALS OF GROUND-WATER MODELING

    EPA Science Inventory

    Ground-water flow and contaminant transport modeling has been used at many hazardous waste sites with varying degrees of success. odels may be used throughout all phases of the site investigation and remediation processes. eveloping a better understanding of ground-water modeling...

  2. COMPILATION OF GROUND-WATER MODELS

    EPA Science Inventory

    Ground-water modeling is a computer-based methodology for mathematical analysis of the mechanisms and controls of ground-water systems for the evaluation of policies, action, and designs that may affect such systems. n addition to satisfying scientific interest in the workings of...

  3. Procedures for ground-water investigations

    SciTech Connect

    Not Available

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program.

  4. COMPILATION OF GROUND-WATER MODELS

    EPA Science Inventory

    Ground-water modeling is a computer-based methodology for mathematical analysis of the mechanisms and controls of ground-water systems for the evaluation of policies, action, and designs that may affect such systems. n addition to satisfying scientific interest in the workings of...

  5. FUNDAMENTALS OF GROUND-WATER MODELING

    EPA Science Inventory

    Ground-water flow and contaminant transport modeling has been used at many hazardous waste sites with varying degrees of success. odels may be used throughout all phases of the site investigation and remediation processes. eveloping a better understanding of ground-water modeling...

  6. Ground-water conditions in Georgia, 1999

    USGS Publications Warehouse

    Cressler, Alan M.

    2000-01-01

    Ground-water conditions in Georgia during 1999 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1999 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards. Ground-water-level and ground-water-quality data are essential for water assessment and management. Ground-water-level fluctuations and trends can be used to estimate changes in aquifer storage resulting from the effects of ground-water withdrawal and recharge from precipitation. These data can be used to address water-management needs and to evaluate the effects of management and conservation programs. As part of the ground-water investigations conducted by the U.S. Geological Survey (USGS), in cooperation with the State of Georgia and city and county governments, a Statewide water-level-measurement program was started in 1938. Initially, this program consisted of an observation-well network in the coastal area of Georgia to monitor variations in ground-water storage and quality. Additional wells were later included in areas where data could be used to aid in water resources development and management. During 1999, periodic water-level measurements were made in 46 wells, and continuous water-level measurements were obtained from 165 wells. Continuous water-level records were obtained using analog (pen and chart

  7. Water resources data, Virginia, water year 2004 volume 2. Ground-water-level and ground-water-quality records

    USGS Publications Warehouse

    White, Roger K.; Powell, Eugene D.; Guyer, Joel R.; Owens, Joseph A.

    2005-01-01

    Water-resources data for the 2004 water year for Virginia consist of records of water levels and water quality of ground-water wells. This report (Volume 2. Ground-Water-Level and Ground-Water-Quality Records) contains water levels at 346 observation wells and water quality at 40 wells. Locations of these wells are shown on figures 4 through 9. The data in this report represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Virginia.

  8. Hanford site ground water protection management plan

    SciTech Connect

    Not Available

    1994-10-01

    Ground water protection at the Hanford Site consists of preventative and remedial measures that are implemented in compliance with a variety of environmental regulations at local, state, and federal levels. These measures seek to ensure that the resource can sustain a broad range of beneficial uses. To effectively coordinate and ensure compliance with applicable regulations, the U.S. Department of Energy has issued DOE Order 5400.1 (DOE 1988a). This order requires all U.S. Department of Energy facilities to prepare separate ground water protection program descriptions and plans. This document describes the Ground Water Protection Management Plan (GPMP) for the Hanford Site located in the state of Washington. DOE Order 5400.1 specifies that the GPMP covers the following general topical areas: (1) documentation of the ground water regime; (2) design and implementation of a ground water monitoring program to support resource management and comply with applicable laws and regulations; (3) a management program for ground water protection and remediation; (4) a summary and identification of areas that may be contaminated with hazardous waste; (5) strategies for controlling hazardous waste sources; (6) a remedial action program; and (7) decontamination, decommissioning, and related remedial action requirements. Many of the above elements are currently covered by existing programs at the Hanford Site; thus, one of the primary purposes of this document is to provide a framework for coordination of existing ground water protection activities. The GPMP provides the ground water protection policy and strategies for ground water protection/management at the Hanford Site, as well as an implementation plan to improve coordination of site ground water activities.

  9. User interface for ground-water modeling: Arcview extension

    USGS Publications Warehouse

    Tsou, M.-S.; Whittemore, D.O.

    2001-01-01

    Numerical simulation for ground-water modeling often involves handling large input and output data sets. A geographic information system (GIS) provides an integrated platform to manage, analyze, and display disparate data and can greatly facilitate modeling efforts in data compilation, model calibration, and display of model parameters and results. Furthermore, GIS can be used to generate information for decision making through spatial overlay and processing of model results. Arc View is the most widely used Windows-based GIS software that provides a robust user-friendly interface to facilitate data handling and display. An extension is an add-on program to Arc View that provides additional specialized functions. An Arc View interface for the ground-water flow and transport models MODFLOW and MT3D was built as an extension for facilitating modeling. The extension includes preprocessing of spatially distributed (point, line, and polygon) data for model input and postprocessing of model output. An object database is used for linking user dialogs and model input files. The Arc View interface utilizes the capabilities of the 3D Analyst extension. Models can be automatically calibrated through the Arc View interface by external linking to such programs as PEST. The efficient pre- and postprocessing capabilities and calibration link were demonstrated for ground-water modeling in southwest Kansas.

  10. Ground-water program in Alabama

    USGS Publications Warehouse

    LaMoreaux, P.E.

    1955-01-01

    Several recent years of drought have emphasized the importance of Alabama's ground-water supplies, a matter of concern to us all.  So far we have been blessed in Alabama with ample ground-water, although a combination of increased use, waste, pollution, and drought has brought about critical local water shortages.  These problems serve as a fair warning of what lies ahead if we do not take the necessary steps to obtan adequate knowledge of our ground-water resources.

  11. Low-Cost 3D Laser Scanning in Air or Water Using Self-Calibrating Structured Light

    NASA Astrophysics Data System (ADS)

    Bleier, M.; Nüchter, A.

    2017-02-01

    In-situ calibration of structured light scanners in underwater environments is time-consuming and complicated. This paper presents a self-calibrating line laser scanning system, which enables the creation of dense 3D models with a single fixed camera and a freely moving hand-held cross line laser projector. The proposed approach exploits geometric constraints, such as coplanarities, to recover the depth information and is applicable without any prior knowledge of the position and orientation of the laser projector. By employing an off-the-shelf underwater camera and a waterproof housing with high power line lasers an affordable 3D scanning solution can be built. In experiments the performance of the proposed technique is studied and compared with 3D reconstruction using explicit calibration. We demonstrate that the scanning system can be applied to above-the-water as well as underwater scenes.

  12. Fracture control of ground water flow and water chemistry in a rock aquitard.

    PubMed

    Eaton, Timothy T; Anderson, Mary P; Bradbury, Kenneth R

    2007-01-01

    There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/S(s)) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies.

  13. Magnificent Ground Water Connection. [Sample Activities].

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    Water conservation and usage is an important concept in science. This document, geared specifically to New England, provides many activities for protecting and discussing ground water situations. Sample activities for grades K-6 include: (1) All the Water in the World; (2) The Case of the Disappearing Water; (3) Deep Subjects--Wells and Ground…

  14. Geostatistical Hydrogeochemical 3d Model for KŁODZKO Underground Water Intake Area Parameters of Underground Waters

    NASA Astrophysics Data System (ADS)

    Namysłowska-Wilczyńska, Barbara

    2013-03-01

    The paper presents the first stage of research on a geostatistical hydrogeochemical 3D model dedicated to the horizontal and vertical spatial and time variation in the topographical, hydrological and quality parameters of underground water in the Kłodzko water intake area. The research covers the period 1977-2012. For this purpose various thematic databases, containing original data on coordinates X, Y (latitude and longitude) and Z (terrain elevation and time - years) and on regionalized variables, i.e., the underground water quality parameters in the Kłodzko water intake area determined for different analytical configurations (22 wells, 14 wells, 14 wells + 3 piezometers), were created. The data were subjected to spatial analyses using statistical methods. The input for the studies was the chemical determination of the quality parameters of underground water samples taken from the wells in the water intake area in different periods of time. Both archival data (acquired in the years 1977-1999, 1977-2011) and the latest data (collected in November 2011 and in January 2012) were analyzed. First, the underground water intake area with 22 wells was investigated. Then in order to assess the current quality of the underground water, 14 wells out of the 22 wells were selected for further chemical analyses and a collection siphon wall was included. Recently, three new piezometers were installed in the water intake area and so new water samples were taken, whereby the databases were supplemented with new chemical determinations. The variation in the topographical parameter (terrain elevation) and in the hydrogeological parameters: water abstraction level Z (with and without the land layout being taken into account) and the depth of occurrence of the water table, was examined. Subsequently, the variation in quality parameters was studied on the basis of data coming from 22 wells, then 14 wells and finally from 14 wells and 3 piezometers. The variation in: Fe, Mn, ammonium

  15. Semi-3D dosimetry of high dose rate brachytherapy using a novel Gafchromic EBT3 film-array water phantom

    NASA Astrophysics Data System (ADS)

    Palmer, A. L.; Nisbet, A.; Bradley, D. A.

    2013-06-01

    There is a need to modernise clinical brachytherapy dosimetry measurement beyond traditional point dose verification to enable appropriate quality control within 3D treatment environments. This is to keep pace with the 3D clinical and planning approaches which often include significant patient-specific optimisation away from 'standard loading patterns'. A multi-dimension measurement system is required to provide assurance of the complex 3D dose distributions, to verify equipment performance, and to enable quality audits. However, true 3D dose measurements around brachytherapy applicators are often impractical due to their complex shapes and the requirement for close measurement distances. A solution utilising an array of radiochromic film (Gafchromic EBT3) positioned within a water filled phantom is presented. A calibration function for the film has been determined over 0 to 90Gy dose range using three colour channel analysis (FilmQAPro software). Film measurements of the radial dose from a single HDR source agree with TPS and Monte Carlo calculations within 5 % up to 50 mm from the source. Film array measurements of the dose distribution around a cervix applicator agree with TPS calculations generally within 4 mm distance to agreement. The feasibility of film array measurements for semi-3D dosimetry in clinical HDR applications is demonstrated.

  16. Light-Driven Overall Water Splitting Enabled by a Photo-Dember Effect Realized on 3D Plasmonic Structures.

    PubMed

    Chen, Min; Gu, Jiajun; Sun, Cheng; Zhao, Yixin; Zhang, Ruoxi; You, Xinyuan; Liu, Qinglei; Zhang, Wang; Su, Yishi; Su, Huilan; Zhang, Di

    2016-07-26

    Photoelectric conversion driven by sunlight has a broad range of energy/environmental applications (e.g., in solar cells and water splitting). However, difficulties are encountered in the separation of photoexcited charges. Here, we realize a long-range (∼1.5 μm period) electric polarization via asymmetric localization of surface plasmons on a three-dimensional silver structure (3D-Ag). This visible-light-responsive effect-the photo-Dember effect, can be analogous to the thermoelectric effect, in which hot carriers are thermally generated instead of being photogenerated. The induced electric field can efficiently separate photogenerated charges, enabling sunlight-driven overall water splitting on a series of dopant-free commercial semiconductor particles (i.e., ZnO, CeO2, TiO2, and WO3) once they are combined with the 3D-Ag substrate. These photocatalytic processes can last over 30 h on 3D-Ag+ZnO, 3D-Ag+CeO2, and 3D-Ag+TiO2, thus demonstrating good catalytic stability for these systems. Using commercial WO3 powder as a reference, the amount of O2 generated with 3D-Ag+CeO2 surpasses even its recently reported counterpart in which sacrificial reagents had to be involved to run half-reactions. This plasmon-mediated charge separation strategy provides an effective way to improve the efficiency of photoelectric energy conversion, which can be useful in photovoltaics and photocatalysis.

  17. Pollution of ground water in Europe

    PubMed Central

    Buchan, S.; Key, A.

    1956-01-01

    This paper discusses pollution of ground water in 20 countries of the European region, giving for each an account of the geology and hydrogeology, water supplies, the extent and nature of ground water pollution, and the legal, administrative, and technical means of controlling that pollution. For the countries not considered in the preceding article on surface water pollution, an account is also given of the superficial physical features, rainfall, population, and industries. A general discussion follows of such questions as the ways in which ground water pollution may occur, the factors mitigating or aggravating pollution, and ways of protection against pollution. The authors consider that the problem of ground water pollution in Europe may well be more serious than it would appear to be on the evidence so far obtained. PMID:13374533

  18. Where this occurs: Ground Water and Drinking Water

    EPA Pesticide Factsheets

    As ground water works its way through the soil, it can pick up excess nutrients and transport them to the water table. When polluted groundwater reaches drinking water systems it can pose serious public health threats.

  19. Simulation of submarine ground water discharge to a marine estuary: Biscayne Bay, Florida.

    PubMed

    Langevin, Christian D

    2003-01-01

    Variable density ground water flow models are rarely used to estimate submarine ground water discharge because of limitations in computer speed, data availability, and availability of a simulation tool that can minimize numerical dispersion. This paper presents an application of the SEAWAT code, which is a combined version of MODFLOW and MT3D, to estimate rates of submarine ground water discharge to a coastal marine estuary. Discharge rates were estimated for Biscayne Bay, Florida, for the period from January 1989 to September 1998 using a three-dimensional, variable density ground water flow and transport model. Hydrologic stresses in the 10-layer model include recharge, evapotranspiration, ground water withdrawals from municipal wellfields, interactions with surface water (canals in urban areas and wetlands in the Everglades), boundary fluxes, and submarine ground water discharge to Biscayne Bay. The model was calibrated by matching ground water levels in monitoring wells, baseflow to canals, and the position of the 1995 salt water intrusion line. Results suggest that fresh submarine ground water discharge to Biscayne Bay may have exceeded surface water discharge during the 1989, 1990, and 1991 dry seasons, but the average discharge for the entire simulation period was only approximately 10% of the surface water discharge to the bay. Results from the model also suggest that tidal canals intercept fresh ground water that might otherwise have discharged directly to Biscayne Bay. This application demonstrates that regional scale variable density models are potentially useful tools for estimating rates of submarine ground water discharge.

  20. Simulation of Submarine Ground Water Discharge to a Marine Estuary: Biscayne Bay, Florida

    USGS Publications Warehouse

    Langevin, C.D.

    2003-01-01

    Variable density ground water flow models are rarely used to estimate submarine ground water discharge because of limitations in computer speed, data availability, and availability of a simulation tool that can minimize numerical dispersion. This paper presents an application of the SEAWAT code, which is a combined version of MODFLOW and MT3D, to estimate rates of submarine ground water discharge to a coastal marine estuary. Discharge rates were estimated for Biscayne Bay, Florida, for the period from January 1989 to September 1998 using a three-dimensional, variable density ground water flow and transport model. Hydrologic stresses in the 10-layer model include recharge, evapotranspiration, ground water withdrawals from municipal wellfields, interactions with surface water (canals in urban areas and wetlands in the Everglades), boundary fluxes, and submarine ground water discharge to Biscayne Bay. The model was calibrated by matching ground water levels in monitoring wells, baseflow to canals, and the position of the 1995 salt water intrusion line. Results suggest that fresh submarine ground water discharge to Biscayne Bay may have exceeded surface water discharge during the 1989, 1990, and 1991 dry seasons, but the average discharge for the entire simulation period was only ???10% of the surface water discharge to the bay. Results from the model also suggest that tidal canals intercept fresh ground water that might otherwise have discharged directly to Biscayne Bay. This application demonstrates that regional scale variable density models are potentially useful tools for estimating rates of submarine ground water discharge.

  1. Studies of the Vector Field in Shallow Water and in the Presence of 3-D Variability

    DTIC Science & Technology

    2015-09-30

    and efficiency of the 3-D MMPE model. This included adaptations of the code to improve the bottom interface treatment, and a complete rewrite of...the code in an upgraded version of Fortran that can be utilized on multi-processor high-performance computer systems. 2 In order to investigate...efficiency were realized by rewriting the code in an updated version of Fortran , including adaptation of the code for use on multi-processor machines

  2. Research into a Single-aperture Light Field Camera System to Obtain Passive Ground-based 3D Imagery of LEO Objects

    NASA Astrophysics Data System (ADS)

    Bechis, K.; Pitruzzello, A.

    2014-09-01

    This presentation describes our ongoing research into using a ground-based light field camera to obtain passive, single-aperture 3D imagery of LEO objects. Light field cameras are an emerging and rapidly evolving technology for passive 3D imaging with a single optical sensor. The cameras use an array of lenslets placed in front of the camera focal plane, which provides angle of arrival information for light rays originating from across the target, allowing range to target and 3D image to be obtained from a single image using monocular optics. The technology, which has been commercially available for less than four years, has the potential to replace dual-sensor systems such as stereo cameras, dual radar-optical systems, and optical-LIDAR fused systems, thus reducing size, weight, cost, and complexity. We have developed a prototype system for passive ranging and 3D imaging using a commercial light field camera and custom light field image processing algorithms. Our light field camera system has been demonstrated for ground-target surveillance and threat detection applications, and this paper presents results of our research thus far into applying this technology to the 3D imaging of LEO objects. The prototype 3D imaging camera system developed by Northrop Grumman uses a Raytrix R5 C2GigE light field camera connected to a Windows computer with an nVidia graphics processing unit (GPU). The system has a frame rate of 30 Hz, and a software control interface allows for automated camera triggering and light field image acquisition to disk. Custom image processing software then performs the following steps: (1) image refocusing, (2) change detection, (3) range finding, and (4) 3D reconstruction. In Step (1), a series of 2D images are generated from each light field image; the 2D images can be refocused at up to 100 different depths. Currently, steps (1) through (3) are automated, while step (4) requires some user interaction. A key requirement for light field camera

  3. STATE WATER RESOURCES RESEARCH INSTITUTE PROGRAM: GROUND WATER RESEARCH.

    USGS Publications Warehouse

    Burton, James S.; ,

    1985-01-01

    This paper updates a review of the accomplishments of the State Water Resources Research Program in ground water contamination research. The aim is to assess the progress made towards understanding the mechanisms of ground water contamination and based on this understanding, to suggest procedures for the prevention and control of ground water contamination. The following research areas are covered: (1) mechanisms of organic contaminant transport in the subsurface environment; (2) bacterial and viral contamination of ground water from landfills and septic tank systems; (3) fate and persistence of pesticides in the subsurface; (4) leachability and transport of ground water pollutants from coal production and utilization; and (5) pollution of ground water from mineral mining activities.

  4. Ground-water conditions in Georgia, 2000

    USGS Publications Warehouse

    Cressler, A.M.; Blackburn, D.K.; McSwain, K.B.

    2001-01-01

    Ground-water conditions in Georgia during 1999 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1999 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards.

  5. Ground-water conditions in Georgia, 1998

    USGS Publications Warehouse

    Cressler, Alan M.

    1999-01-01

    Ground-water conditions in Georgia during 1998 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1998 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards.

  6. Coupling Between Microstrip Lines with Finite Width Ground Plane Embedded in Polyimide Layers for 3D-MMICs on Si

    NASA Technical Reports Server (NTRS)

    Ponchak, George E.; Dalton, Edan; Tentzeris, Emmanouil M.; Papapolymerou, John; Williams, W. Dan (Technical Monitor)

    2001-01-01

    Three-dimensional circuits built upon multiple layers of polyimide are required for constructing Si/SiGe monolithic microwave/millimeter-wave integrated circuits on complementary metal oxide semiconductor (CMOS) (low resistivity) Si wafers. Thin film microstrip lines (TFMS) with finite width ground planes embedded in the polyimide are often used. However, the closely spaced TFMS lines are susceptible to high levels of coupling, which degrades circuit performance. In this paper, Finite Difference Time Domain (FDTD) analysis and experimental measurements are used to show that the ground planes must be connected by via holes to reduce coupling in both the forward and backward directions.

  7. Ground-water resources of Kansas

    USGS Publications Warehouse

    Moore, R.C.; Lohman, S.W.; Frye, J.C.; Waite, H.A.; McLaughlin, Thad G.; Latta, Bruce

    1940-01-01

    Importance of ground-water resources.—The importance of Kansas' ground-water resources may be emphasized from various viewpoints and in different ways. More than three-fourths of the public water supplies of Kansas are obtained from wells. In 1939, only 60 out of 375 municipal water supplies in Kansas, which is 16 percent, utilized surface waters. If the water wells of the cities and those located on all privately owned land in the state were suddenly destroyed, making it necessary to go to streams, springs, lakes (which are almost all artificial), and ponds for water supply domestic, stock, and industrial use, there would be almost incalculable difficulty and expense. If one could not go to springs, or dig new wells, or use any surface water derived from underground flow, much of Kansas would become uninhabitable.  These suggested conditions seem absurd, but they emphasize our dependence on ground-water resources. Fromm a quantitative standpoint, ground-water supplies existent in Kansas far outweigh surface waters that are present in the state at any one time. No exact figures for such comparison can be given, but, taking 384 square miles as the total surface water area of the state and estimating an average water depth of five feet, the computed volume of surface waters is found to be 1/100th of that of the conservatively estimated ground-water storage in Kansas. The latter takes account only of potable fresh water and is based on an assumed mean thickness of ten feet of reservoir having an effective porosity of twenty percent. It is to be remembered, however, that most of the surface water is run-off, which soon leaves the state, stream valleys being replenished from rainfall and flow from ground-water reservoirs. Most of the ground-water supplies, on the other hand, have existed for many years with almost no appreciable movement--in fact, it is reasonably certain that some well water drawn from beneath the surface of Kansas in 1940 represents rainfall in

  8. 1D and 3D inversion of VES data to outline a fresh water zone floating over saline water body at the northwestern coast of Egypt

    NASA Astrophysics Data System (ADS)

    Massoud, Usama; Soliman, Mamdouh; Taha, Ayman; Khozym, Ashraf; Salah, Hany

    2015-12-01

    Seawater intrusion is a widespread environmental problem in the Egyptian coastal aquifers. It affects the groundwater used in domestic and agricultural activities along these coasts. In this study, resistivity survey in the form of Vertical Electrical Sounding (VES) was conducted at ZAWYET EL HAWALA cultivated site, northwest coast of Egypt to outline a freshwater zone overlies the main saltwater body, and to determine the most suitable location for drilling water well for irrigation purposes. The VES data were measured at 11 stations in the studied site. After processing, the data were inverted in 1-D and 3-D schemes and the final model was presented as resistivity slices with depth. The results indicate that the effect of saltwater intrusion was observed, as low resistivity values, at 7.5 m below ground surface (bgs) at the northern part of the study area (toward the Mediterranean Sea), and extends southward with increasing depth covering the whole area at about 30 m bgs. The fresh water zone shows a minimum thickness of less than 7.5 m at the northern side and a maximum thickness of about 20 m at the southern side of the area. The proper site for drilling water well tap and the freshwater zone is the location of VES6 or VES9 with a maximum well depth of about 20 m bgs. The water withdrawal from the proposed well should be controlled not to raise the main saline water table in the well site. The main sources of the freshwater zone are the rainfall and surface runoff descending from the southern tableland. Excess rainfall and surface runoff can be avoided from direct discharge to the sea by collecting them in man-made outlined trenches and re-using the stored water in irrigation during the dry seasons.

  9. Construction of a 3d Measurable Virtual Reality Environment Based on Ground Panoramic Images and Orbital Imagery for Planetary Exploration Applications

    NASA Astrophysics Data System (ADS)

    Di, K.; Liang, J.; Liu, Z.

    2011-08-01

    This paper presents a method of constructing a measurable virtual reality environment based on ground (lander/rover) panoramic images and orbital imagery. Ground panoramic images acquired by a lander/rover at different azimuth and elevation angles are automatically registered, seamlessly mosaicked and projected onto a cylindrical surface. A specific function is developed for inverse calculation from the panorama back to the original images so that the 3D information associated with the original stereo images can be retrieved or computed. The three-dimensional measurable panorama is integrated into a globe viewer based on NASA World Wind. The techniques developed in this research can be used in visualization of and measuring the orbital and ground images for planetary exploration missions, especially rover missions.

  10. Regional ground-water evapotranspiration and ground-water budgets, Great Basin, Nevada

    USGS Publications Warehouse

    Nichols, William D.

    2000-01-01

    PART A: Ground-water evapotranspiration data from five sites in Nevada and seven sites in Owens Valley, California, were used to develop equations for estimating ground-water evapotranspiration as a function of phreatophyte plant cover or as a function of the depth to ground water. Equations are given for estimating mean daily seasonal and annual ground-water evapotranspiration. The equations that estimate ground-water evapotranspiration as a function of plant cover can be used to estimate regional-scale ground-water evapotranspiration using vegetation indices derived from satellite data for areas where the depth to ground water is poorly known. Equations that estimate ground-water evapotranspiration as a function of the depth to ground water can be used where the depth to ground water is known, but for which information on plant cover is lacking. PART B: Previous ground-water studies estimated groundwater evapotranspiration by phreatophytes and bare soil in Nevada on the basis of results of field studies published in 1912 and 1932. More recent studies of evapotranspiration by rangeland phreatophytes, using micrometeorological methods as discussed in Chapter A of this report, provide new data on which to base estimates of ground-water evapotranspiration. An approach correlating ground-water evapotranspiration with plant cover is used in conjunction with a modified soil-adjusted vegetation index derived from Landsat data to develop a method for estimating the magnitude and distribution of ground-water evapotranspiration at a regional scale. Large areas of phreatophytes near Duckwater and Lockes in Railroad Valley are believed to subsist on ground water discharged from nearby regional springs. Ground-water evapotranspiration by the Duckwater phreatophytes of about 11,500 acre-feet estimated by the method described in this report compares well with measured discharge of about 13,500 acre-feet from the springs near Duckwater. Measured discharge from springs near Lockes

  11. Water-based polyurethane 3D printed scaffolds with controlled release function for customized cartilage tissue engineering.

    PubMed

    Hung, Kun-Che; Tseng, Ching-Shiow; Dai, Lien-Guo; Hsu, Shan-hui

    2016-03-01

    Conventional 3D printing may not readily incorporate bioactive ingredients for controlled release because the process often involves the use of heat, organic solvent, or crosslinkers that reduce the bioactivity of the ingredients. Water-based 3D printing materials with controlled bioactivity for customized cartilage tissue engineering is developed in this study. The printing ink contains the water dispersion of synthetic biodegradable polyurethane (PU) elastic nanoparticles, hyaluronan, and bioactive ingredients TGFβ3 or a small molecule drug Y27632 to replace TGFβ3. Compliant scaffolds are printed from the ink at low temperature. These scaffolds promote the self-aggregation of mesenchymal stem cells (MSCs) and, with timely release of the bioactive ingredients, induce the chondrogenic differentiation of MSCs and produce matrix for cartilage repair. Moreover, the growth factor-free controlled release design may prevent cartilage hypertrophy. Rabbit knee implantation supports the potential of the novel 3D printing scaffolds in cartilage regeneration. We consider that the 3D printing composite scaffolds with controlled release bioactivity may have potential in customized tissue engineering. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. 3D branched ZnO nanowire arrays decorated with plasmonic au nanoparticles for high-performance photoelectrochemical water splitting.

    PubMed

    Zhang, Xing; Liu, Yang; Kang, Zhenhui

    2014-03-26

    Plasmonic photoelectrochemical (PEC) water splitting is very promising in the conversion of abundant solar energy into chemical energy. However, the solar-to-hydrogen efficiencies reported so far are still too low for practical use, which can be improved by optimizing the design and synthesis of individual blocks (i. e., the compositions, sizes, shapes of the metal and the coupling semiconductors) and the assembly of these blocks into targeted three-dimensional (3D) structures. Here, we constructed a composite plasmonic metal/semiconductor photoanode by decorating gold nanoparticles (Au NPs) on 3D branched ZnO nanowire arrays (B-ZnO NWs) through a series of simple solution chemical routes. The 3D ordered Au/B-ZnO NWs photoanodes exhibited excellent PEC activities in both ultraviolet and visible region. The improved photoactivities in visible region were demonstrated to be caused by the surface-plasmon-resonance effect of Au NPs. The photoconversion efficiency of Au/B-ZnO NWs photoanode reached 0.52% under simulated sunlight illumination. This is a high value of solar-to-hydrogen efficiencies reported till nowadays for plasmonic PEC water splitting, which was mainly benefit from the extensive metal/semiconductor interfaces for efficient extraction of hot electron from Au NPs and excellent charge-carries collection efficiency of the 3D ordered Au/B-ZnO NWs photoelectrode.

  13. Ground-Water Protection and Monitoring Program

    SciTech Connect

    Dresel, P.E.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the ground-water protection and monitoring program strategy for the Hanford Site in 1994. Two of the key elements of this strategy are to (1) protect the unconfined aquifer from further contamination, and (2) conduct a monitoring program to provide early warning when contamination of ground water does occur. The monitoring program at Hanford is designed to document the distribution and movement of existing ground-water contamination and provides a historical baseline for evaluating current and future risk from exposure to the contamination and for deciding on remedial action options.

  14. 2D and 3D separate and joint inversion of airborne ZTEM and ground AMT data: Synthetic model studies

    NASA Astrophysics Data System (ADS)

    Sasaki, Yutaka; Yi, Myeong-Jong; Choi, Jihyang

    2014-05-01

    The ZTEM (Z-axis Tipper Electromagnetic) method measures naturally occurring audio-frequency magnetic fields and obtains the tipper function that defines the relationship among the three components of the magnetic field. Since the anomalous tipper responses are caused by the presence of lateral resistivity variations, the ZTEM survey is most suited for detecting and delineating conductive bodies extending to considerable depths, such as graphitic dykes encountered in the exploration of unconformity type uranium deposit. Our simulations shows that inversion of ZTEM data can detect reasonably well multiple conductive dykes placed 1 km apart. One important issue regarding ZTEM inversion is the effect of the initial model, because homogeneous half-space and (1D) layered structures produce no responses. For the 2D model with multiple conductive dykes, the inversion results were useful for locating the dykes even when the initial model was not close to the true background resistivity. For general 3D structures, however, the resolution of the conductive bodies can be reduced considerably depending on the initial model. This is because the tipper magnitudes from 3D conductors are smaller due to boundary charges than the 2D responses. To alleviate this disadvantage of ZTEM surveys, we combined ZTEM and audio-frequency magnetotelluric (AMT) data. Inversion of sparse AMT data was shown to be effective in providing a good initial model for ZTEM inversion. Moreover, simultaneously inverting both data sets led to better results than the sequential approach by enabling to identify structural features that were difficult to resolve from the individual data sets.

  15. Microfluidic Fabrication of Bio-Inspired Microfibers with Controllable Magnetic Spindle-Knots for 3D Assembly and Water Collection.

    PubMed

    He, Xiao-Heng; Wang, Wei; Liu, Ying-Mei; Jiang, Ming-Yue; Wu, Fang; Deng, Ke; Liu, Zhuang; Ju, Xiao-Jie; Xie, Rui; Chu, Liang-Yin

    2015-08-12

    A simple and flexible approach is developed for controllable fabrication of spider-silk-like microfibers with tunable magnetic spindle-knots from biocompatible calcium alginate for controlled 3D assembly and water collection. Liquid jet templates with volatile oil drops containing magnetic Fe3O4 nanoparticles are generated from microfluidics for fabricating spider-silk-like microfibers. The structure of jet templates can be precisely adjusted by simply changing the flow rates to tailor the structures of the resultant spider-silk-like microfibers. The microfibers can be well manipulated by external magnetic fields for controllably moving, and patterning and assembling into different 2D and 3D structures. Moreover, the dehydrated spider-silk-like microfibers, with magnetic spindle-knots for collecting water drops, can be controllably assembled into spider-web-like structures for excellent water collection. These spider-silk-like microfibers are promising as functional building blocks for engineering complex 3D scaffolds for water collection, cell culture, and tissue engineering.

  16. Octanol-Water Partition Coefficient from 3D-RISM-KH Molecular Theory of Solvation with Partial Molar Volume Correction.

    PubMed

    Huang, WenJuan; Blinov, Nikolay; Kovalenko, Andriy

    2015-04-30

    The octanol-water partition coefficient is an important physical-chemical characteristic widely used to describe hydrophobic/hydrophilic properties of chemical compounds. The partition coefficient is related to the transfer free energy of a compound from water to octanol. Here, we introduce a new protocol for prediction of the partition coefficient based on the statistical-mechanical, 3D-RISM-KH molecular theory of solvation. It was shown recently that with the compound-solvent correlation functions obtained from the 3D-RISM-KH molecular theory of solvation, the free energy functional supplemented with the correction linearly related to the partial molar volume obtained from the Kirkwood-Buff/3D-RISM theory, also called the "universal correction" (UC), provides accurate prediction of the hydration free energy of small compounds, compared to explicit solvent molecular dynamics [ Palmer , D. S. ; J. Phys.: Condens. Matter 2010 , 22 , 492101 ]. Here we report that with the UC reparametrized accordingly this theory also provides an excellent agreement with the experimental data for the solvation free energy in nonpolar solvent (1-octanol) and so accurately predicts the octanol-water partition coefficient. The performance of the Kovalenko-Hirata (KH) and Gaussian fluctuation (GF) functionals of the solvation free energy, with and without UC, is tested on a large library of small compounds with diverse functional groups. The best agreement with the experimental data for octanol-water partition coefficients is obtained with the KH-UC solvation free energy functional.

  17. Ground-Water Recharge in Minnesota

    USGS Publications Warehouse

    Delin, G.N.; Falteisek, J.D.

    2007-01-01

    'Ground-water recharge' broadly describes the addition of water to the ground-water system. Most water recharging the ground-water system moves relatively rapidly to surface-water bodies and sustains streamflow, lake levels, and wetlands. Over the long term, recharge is generally balanced by discharge to surface waters, to plants, and to deeper parts of the ground-water system. However, this balance can be altered locally as a result of pumping, impervious surfaces, land use, or climate changes that could result in increased or decreased recharge. * Recharge rates to unconfined aquifers in Minnesota typically are about 20-25 percent of precipitation. * Ground-water recharge is least (0-2 inches per year) in the western and northwestern parts of the State and increases to greater than 6 inches per year in the central and eastern parts of the State. * Water-level measurement frequency is important in estimating recharge. Measurements made less frequently than about once per week resulted in as much as a 48 percent underestimation of recharge compared with estimates based on an hourly measurement frequency. * High-quality, long-term, continuous hydrologic and climatic data are important in estimating recharge rates.

  18. Ground water in Tooele Valley, Utah

    USGS Publications Warehouse

    Gates, J.S.; Keller, O.A.

    1970-01-01

    This short report was written by condensing parts of a technical report on the ground water in Tooele Valley, which was prepared as part of a cooperative program between the Utah Department of Natural Resources, Division of Water Rights, and the U. S. Geological Survey to study water in Utah. If you would like to read the more detailed technical report, write for a copy of the Utah State Engineer Technical Publication 12, “Reevaluation of the ground-water resources of Tooele Valley, Utah” by J. S. Gates. Copies can be obtained free of charge from the Division of Water Rights, State Capitol, Salt Lake City, Utah 84114.

  19. 3-D Sound Propagation and Acoustic Inversions in Shallow Water Oceans

    DTIC Science & Technology

    2012-12-19

    models provide a physical insight into this shadowing effect (see Figure 8). In addition, the model suggests that 3-D sound focusing due to the canyon...Ocean. Eng., vol. 35, pp. 710-721. [published, refereed] 2010 J.F. Lynch, Y.-T. Lin, T.F. Duda, and A.E. Newhall, "Acoustic Ducting, Shadowing ...fixed arc-length grid.] 10 Modeling comparisons Propagate over seamount , off center Source at 250 m, 100Hz 4 cases - (1) Nx2D, (2) Cartesian, (3

  20. Near Real-time Full-wave Centroid Moment Tensor (CMT) Inversion for Ground-motion forecast in 3D Earth Structure of Southern California

    NASA Astrophysics Data System (ADS)

    Chen, P.; Lee, E.; Jordan, T. H.; Maechling, P. J.

    2011-12-01

    Accurate and rapid CMT inversion is important for seismic hazard analysis. We have developed an algorithm for very rapid full-wave CMT inversions in a 3D Earth structure model and applied it on earthquakes recorded by the Southern California Seismic Network (SCSN). The procedure relies on the use of receiver-side Green tensors (RGTs), which comprise the spatial-temporal displacements produced by the three orthogonal unit impulsive point forces acting at the receiver. We have constructed a RGT database for 219 broadband stations in Southern California using an updated version of the 3D SCEC Community Velocity Model (CVM) version 4.0 and a staggered-grid finite-difference code. Finite-difference synthetic seismograms for any earthquake in our modeling volume can be simply calculated by extracting a small, source-centered volume from the RGT database and applying the reciprocity principle. We have developed an automated algorithm that combines a grid-search for suitable epicenter and focal mechanisms with a gradient-descent method that further refines the grid-search results. In this algorithm, the CMT solutions are inverted near real-time by using waveform in a 3D Earth structure. Comparing with the CMT solutions provided by the Southern California Seismic Network (SCSN) shows that our solutions generally provide better fit to the observed waveforms. Our algorithm may provide more robust CMT solutions for earthquakes in Southern California. In addition, the rapid and accurate full-wave CMT inversion has potential to extent to accurate near real-time ground-motion prediction based on 3D structure model for earthquake early warning purpose. When combined with real-time telemetered waveform recordings, our algorithm can provide (near) real-time ground-motion forecast.

  1. Unimpeded permeation of water through biocidal graphene oxide sheets anchored on to 3D porous polyolefinic membranes

    NASA Astrophysics Data System (ADS)

    Mural, Prasanna Kumar S.; Jain, Shubham; Kumar, Sachin; Madras, Giridhar; Bose, Suryasarathi

    2016-04-01

    3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and hot-pressed samples revealed a clear picture as to how the morphology develops and coarsens over a function of time during post-processing operations like compression molding. The coarsening of PE/PEO blends was traced using X-ray micro-computed tomography and scanning electron microscopy (SEM) of annealed blends at different times. It is now understood from X-ray micro-computed tomography that by the addition of a compatibilizer (here lightly maleated PE), a stable morphology can be visualized in 3D. In order to anchor biocidal graphene oxide sheets onto these 3D porous membranes, the PE membranes were chemically modified with acid/ethylene diamine treatment to anchor the GO sheets which were further confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and surface Raman mapping. The transport properties through the membrane clearly reveal unimpeded permeation of water which suggests that anchoring GO on to the membranes does not clog the pores. Antibacterial studies through the direct contact of bacteria with GO anchored PE membranes resulted in 99% of bacterial inactivation. The possible bacterial inactivation through physical disruption of the bacterial cell wall and/or reactive oxygen species (ROS) is discussed herein. Thus this study opens new avenues in designing polyolefin based antibacterial 3D porous membranes for water purification.3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and

  2. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  3. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of: (1...

  4. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  5. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  6. Ground-water conditions in Georgia, 1997

    USGS Publications Warehouse

    Cressler, A.M.

    1998-01-01

    Ground-water conditions in Georgia during 1997 and for the period of record were evaluated using data from ground-water-level and ground-water-quality monitoring networks. Data for 1997 included in this report are from continuous water-level records from 71 wells and chloride analyses from 14 wells. In 1997, annual mean ground-water levels in Georgia ranged from 6.2 feet (ft) lower to 5.6 ft higher than in 1996. Of the 71 wells summarized in this report, 23 wells had annual mean water levels that were higher, 35 wells had annual mean water levels that were lower, and 11 wells had annual mean water levels that were about the same in 1997 as during 1996. Data for two wells are incomplete because data collection was discontinued at one well, and the equipment was vandalized at one well. Record-low daily mean water levels were recorded in six wells tapping the Upper Floridan aquifer, one well tapping the Caliborne aquifer, two wells tapping the Clayton aquifer, and three wells tapping Cretaceous aquifers. These record lows were from 0.2 to 5.6 ft lower than previous record lows. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standard. Ground-water-level and ground-water-quality data are essential for water assessment and management. Ground-water-level fluctuations and trends can be used to estimate changes in aquifer storage resulting from the effects of ground-water withdrawal and recharge from precipitation. These data can be used to address water-management needs and to evaluate the effects of management and conservation programs. As part of the ground-water

  7. 3D Dynamic Rupture with Slip Reactivation and Ground Motion Simulations of the 2011 Mw 9.0 Tohoku Earthquake

    NASA Astrophysics Data System (ADS)

    Dalguer, Luis; Galvez, Percy

    2013-04-01

    Seismological, geodetic and tsunami observations, including kinematic source inversion and back-projection models of the giant megathrust 2011 Mw 9.0 Tohoku earthquake indicate that the earthquake featured complex rupture patterns, with multiple rupture fronts and rupture styles. The compilation of these studies reveals fundamentally three main feature: 1) spectacular large slip over 50m, 2) the existence of slip reactivation and 3) distinct regions of low and high frequency radiation. In this paper we investigate the possible mechanisms causing the slip reactivation. For this purpose we perform earthquakes dynamic rupture and strong ground motion simulations. We investigate two mechanisms as potential sources of slip reactivation: 1) The additional push to the earthquake rupture (slip reactivation) comes from the rupture front back propagating from the free-surface after rupturing the trench of the fault, a phenomena usually observed in dynamic rupture simulations of dipping faults (e.g. Dalguer et al. 2001). This mechanism produces smooth slip velocity reactivation with low frequency content. 2) Slip reactivation governed by the friction constitutive low (in the form given by Kanamori and Heaton, 2000) in which frictional strength drops initially to certain value, but then at large slips there is a second drop in frictional strength. The slip velocity caused by this mechanism is a sharp pulse capable to radiate stronger ground motion. Our simulations show that the second mechanism produces synthetic ground motion pattern along the Japanese cost of the Tohoku event consistent with the observed ground motion. In addition, the rupture pattern with slip reactivation is also consistent with kinematic source inversion models in which slip reactivation is observed. Therefore we propose that the slip reactivation observed in this earthquake is results of strong frictional strength drop, maybe caused by fault melting, pressurization, lubrication or other thermal weakening

  8. Ground water geology of Edwards County, Texas

    USGS Publications Warehouse

    Long, Archie T.

    1963-01-01

    About 150,000 acre-feet of water is recharged annually to and discharged from the Edwards and associated limestones in Edwards County. Most of this water is available for additional development inasmuch as only about 900 acre-feet per year is currently being used; however, additional development of ground water will result in a reduction in streamflow.

  9. Understanding thermal Marangoni flow in water sessile evaporating drops via 3D-PTV

    NASA Astrophysics Data System (ADS)

    Rossi, Massimiliano; Marin, Alvaro; Kaehler, Christian J.

    2016-11-01

    Understanding the flow inside sessile evaporating drops is of great interest both from a fundamental and technological point of view. Despite strong research efforts in the recent years, a complete picture on the phenomena involved in this process and a way to control them is still far to be reached. This is due to a lack of reliable experimental data on the internal flow but more dramatically on the interfacial flow. A relevant open debate concerns the role played by the Marangoni flow induced by thermal gradients. We recently show how 3D particle tracking techniques are suitable to measure the internal flow of drops and to derive quantities such as surface shear and surface tension differences. Such experiments also indicated an increase of the thermal Marangoni flow as the droplet becomes thinner, in disagreement with current theoretical models and simulations. A possible reason for that could be a discrepancy of the imposed boundary conditions in the simulations and the experimental ones. This work follows up these observations with fully 3D time-resolved measurements of the flow inside drops evaporating on a quartz substrate, which temperature is controlled using a feedback temperature control and a microscope incubator system. Supported by DFG, Grant No. KA 1808/22.

  10. Efficient Electrochemical and Photoelectrochemical Water Splitting by a 3D Nanostructured Carbon Supported on Flexible Exfoliated Graphene Foil.

    PubMed

    Hou, Yang; Qiu, Ming; Zhang, Tao; Ma, Ji; Liu, Shaohua; Zhuang, Xiaodong; Yuan, Chris; Feng, Xinliang

    2017-01-01

    A novel 3D Co-Nx |P-complex-doped carbon grown on flexible exfoliated graphene foil is designed and constructed for both electrochemical and photoelectrochemical water splitting. The coordination of Co-Nx active centers hybridized with that of neighboring P atoms enhances the electron transfer and optimizes the charge distribution of the carbon surface, which synergistically promotes reaction kinetics by providing more exposed active sites. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. European Pressurized water Reactor (EPR) SAR ATWS Accident Analyses by using 3D Code Internal Coupling Method

    SciTech Connect

    Gagner, Renata; Lafitte, Helene; Dormeau, Pascal; Stoudt, Roger H.

    2004-07-01

    Anticipated Transients Without Scram (ATWS) accident analyses make part of the Safety Analysis Report of the European Pressurized water Reactor (EPR), covering Risk Reduction Category A (Core Melt Prevention) events. This paper deals with three of the most penalizing RRC-A sequences of ATWS caused by mechanical blockage of the control/shutdown rods, regarding their consequences on the Reactor Coolant System (RCS) and core integrity. A new 3D code internal coupling calculation method has been introduced. (authors)

  12. Dynamically coupled 3D pollutant dispersion model for assessing produced water discharges in the Canadian offshore area.

    PubMed

    Zhao, Lin; Chen, Zhi; Lee, Kenneth

    2013-02-05

    Produced water is the contaminated water that is brought to the surface in the process of recovering oil and gas. On the basis of discharge volume, this type of contaminated water is the largest contributor to the offshore waste stream. Modeling studies of large amounts of wastewater discharge into offshore areas have helped in the understanding of pollutant dispersion behaviors in marine environments and in further evaluating the potential environmental effects resulting from produced water discharges. This study presents an integrated three-dimensional (3D) approach for the simulation of produced water discharges in offshore areas. Specifically, an explicit second-order finite difference method was used to model the far-field pollutant dispersion behavior, and this method was coupled with the jet-plume model JETLAG with an extension of the 3D cross-flow conditions to simulate the near-field mixing processes. A dynamic coupling technique with full consideration of the interaction between the discharged fluids and receiving waters was employed in the model. A case study was conducted on the Grand Banks of Newfoundland, Canada. The field validation of the modeling results was conducted for both the near-field and far-field dispersion processes, and the modeling results were in good agreement with the field observations. This study provides an integrated system tool for the simulation of complex transport processes in offshore areas, and the results from such modeling systems can be further used for the risk assessment analysis of the surface water environment.

  13. Ground-water models cannot be validated

    USGS Publications Warehouse

    Konikow, L.F.; Bredehoeft, J.D.

    1992-01-01

    Ground-water models are embodiments of scientific hypotheses. As such, the models cannot be proven or validated, but only tested and invalidated. However, model testing and the evaluation of predictive errors lead to improved models and a better understanding of the problem at hand. In applying ground-water models to field problems, errors arise from conceptual deficiencies, numerical errors, and inadequate parameter estimation. Case histories of model applications to the Dakota Aquifer, South Dakota, to bedded salts in New Mexico, and to the upper Coachella Valley, California, illustrate that calibration produces a nonunique solution and that validation, per se, is a futile objective. Although models are definitely valuable tools for analyzing ground-water systems, their predictive accuracy is limited. The terms validation and verification are misleading and their use in ground-water science should be abandoned in favor of more meaningful model-assessment descriptors. ?? 1992.

  14. Fundamentals of Ground-Water Modeling

    EPA Pesticide Factsheets

    This paper presents an overview of the essential components of ground-water flow and contaminant transport modeling in saturated porous media. While fractured rocks and fractured porous rocks may behave like porous media with respect to many flow and...

  15. Section 9: Ground Water - Likelihood of Release

    EPA Pesticide Factsheets

    HRS training. the ground water pathway likelihood of release factor category reflects the likelihood that there has been, or will be, a release of hazardous substances in any of the aquifers underlying the site.

  16. Reagent removal of manganese from ground water

    NASA Astrophysics Data System (ADS)

    Brayalovsky, G.; Migalaty, E.; Naschetnikova, O.

    2017-06-01

    The study is aimed at the technology development of treating drinking water from ground waters with high manganese content and oxidizability. Current technologies, physical/chemical mechanisms and factors affecting in ground treatment efficiency are reviewed. Research has been conducted on manganese compound removal from ground waters with high manganese content (5 ppm) and oxidizability. The studies were carried out on granular sorbent industrial ODM-2F filters (0.7-1.5 mm fraction). It was determined that conventional reagent oxidization technologies followed by filtration do not allow us to obtain the manganese content below 0.1 ppm when treating ground waters with high oxidizability. The innovative oxidation-based manganese removal technology with continuous introduction of reaction catalytic agent is suggested. This technology is effective in alkalization up to pH 8.8-9. Potassium permanganate was used as a catalytic agent, sodium hypochlorite was an oxidizer and cauistic soda served an alkalifying agent.

  17. Section 10: Ground Water - Waste Characteristics & Targets

    EPA Pesticide Factsheets

    HRS Training. The waste characteristics factor category in the ground water pathway is made up of two components: the toxicity/mobility of the most hazardous substance associated with the site and the hazardous waste quantity at the site.

  18. A HIGHLY COLLIMATED WATER MASER BIPOLAR OUTFLOW IN THE CEPHEUS A HW3d MASSIVE YOUNG STELLAR OBJECT

    SciTech Connect

    Chibueze, James O.; Imai, Hiroshi; Tafoya, Daniel; Omodaka, Toshihiro; Chong, Sze-Ning; Kameya, Osamu; Hirota, Tomoya; Torrelles, Jose M.

    2012-04-01

    We present the results of multi-epoch very long baseline interferometry (VLBI) water (H{sub 2}O) maser observations carried out with the VLBI Exploration of Radio Astrometry toward the Cepheus A HW3d object. We measured for the first time relative proper motions of the H{sub 2}O maser features, whose spatio-kinematics traces a compact bipolar outflow. This outflow looks highly collimated and expanding through {approx}280 AU (400 mas) at a mean velocity of {approx}21 km s{sup -1} ({approx}6 mas yr{sup -1}) without taking into account the turbulent central maser cluster. The opening angle of the outflow is estimated to be {approx}30 Degree-Sign . The dynamical timescale of the outflow is estimated to be {approx}100 years. Our results provide strong support that HW3d harbors an internal massive young star, and the observed outflow could be tracing a very early phase of star formation. We also have analyzed Very Large Array archive data of 1.3 cm continuum emission obtained in 1995 and 2006 toward Cepheus A. The comparative result of the HW3d continuum emission suggests the possibility of the existence of distinct young stellar objects in HW3d and/or strong variability in one of their radio continuum emission components.

  19. Spectroscopic Evidence for a 3d(10) Ground State Electronic Configuration and Ligand Field Inversion in [Cu(CF3)4](1-).

    PubMed

    Walroth, Richard C; Lukens, James T; MacMillan, Samantha N; Finkelstein, Kenneth D; Lancaster, Kyle M

    2016-02-17

    The contested electronic structure of [Cu(CF3)4](1-) is investigated with UV/visible/near IR spectroscopy, Cu K-edge X-ray absorption spectroscopy, and 1s2p resonant inelastic X-ray scattering. These data, supported by density functional theory, multiplet theory, and multireference calculations, support a ground state electronic configuration in which the lowest unoccupied orbital is of predominantly trifluoromethyl character. The consensus 3d(10) configuration features an inverted ligand field in which all five metal-localized molecular orbitals are located at lower energy relative to the trifluoromethyl-centered σ orbitals.

  20. MTBE concentrations in ground water in Pennsylvania

    USGS Publications Warehouse

    McAuley, Steven D.

    2003-01-01

    The distribution, concentrations, and detection frequency of methyl tert-butyl-ether (MTBE), a gasoline additive used in reformulated gasoline to improve air quality, were characterized in Pennsylvania?s ground water. Two sources of MTBE in ground water, the atmosphere and storage-tank release sites, were examined. An analysis of atmospheric MTBE concentrations shows that MTBE detections (MTBE greater than or equal to 0.2 micrograms per liter) in ground water are more likely the result of storage-tank releases than atmospheric deposition. A comparison of 86 ground-water samples near storage-tank releases and 359 samples from ambient ground water (not thought to be affected by point-source releases of MTBE or BTEX compounds) shows that samples within about 0.5 mile downgradient of storagetank release sites have significantly greater MTBE detection frequency than ambient ground-water samples. Aquifer type, land use, and the use of Reformulated Gasoline (RFG) are associated with high rates of occurrence of MTBE in ground water in Pennsylvania. Ground-water samples from wells in crystalline-rock aquifers near storage- tank release sites have a significantly greater MTBE detection frequency (57 percent) compared to other aquifers. Samples from wells in urban areas have a significantly greater MTBE detection frequency compared to ambient samples in agricultural and forested areas. Samples from the RFG-use areas in the five southeastern counties of Pennsylvania have a significantly greater MTBE detection frequency than samples outside of the RFG-use area. MTBE detection frequency of samples near storage- tank release sites in the RFG-use area (45 percent) are significantly greater than ambient samples in the RFG-use area.

  1. Ground-water conditions in Georgia, 1993

    USGS Publications Warehouse

    Joiner, C.N.; Cressler, A.M.

    1994-01-01

    Ground-water conditions during 1993 and recent ground-water level and quality trends in Georgia were evaluated using data from precipitation, ground-water, and ground-water quality monitoring networks. Data for 1993 included in this report are from precipitation records from 10 National Weather Service stations, continuous water-level records from 72 wells, and chloride analyses from 13 wells. Annual mean ground-water levels in Georgia in 1993 ranged from about 3.2 feet higher to about 9.6 feet lower than in 1992. Of the 72 wells summarized in this report, 30 wells had annual mean water levels that were higher and 42 wells had annual mean water levels that were lower in 1993 than in 1992. Record-high daily mean water levels were recorded in one well tapping the surficial aquifer, one well tapping the Upper Floridan aquifer, one well tapping the Claiborne aquifer, and one well tapping the crystalline- rock aquifers. These record highs were from about 0.1 to 0.7 feet higher than previous record highs. Record-low daily mean water levels were recorded in one well tapping the surficial aquifer, two wells tapping the Upper Floridan aquifer, four wells tapping the Cretaceous aquifer, one well tapping the Dublin-Midville aquifer system, and one well tapping the crystalline-rock aquifers. These record lows were from about 0.1 foot to 7.2 feet lower than the previous record lows. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was below drinking water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency and has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking water standards.

  2. 3D crustal structure and long-period ground motions from a M9.0 megathrust earthquake in the Pacific Northwest region

    USGS Publications Warehouse

    Olsen, K.B.; Stephenson, W.J.; Geisselmeyer, A.

    2008-01-01

    We have developed a community velocity model for the Pacific Northwest region from northern California to southern Canada and carried out the first 3D simulation of a Mw 9.0 megathrust earthquake rupturing along the Cascadia subduction zone using a parallel supercomputer. A long-period (<0.5 Hz) source model was designed by mapping the inversion results for the December 26, 2004 Sumatra–Andaman earthquake (Han et al., Science 313(5787):658–662, 2006) onto the Cascadia subduction zone. Representative peak ground velocities for the metropolitan centers of the region include 42 cm/s in the Seattle area and 8–20 cm/s in the Tacoma, Olympia, Vancouver, and Portland areas. Combined with an extended duration of the shaking up to 5 min, these long-period ground motions may inflict significant damage on the built environment, in particular on the highrises in downtown Seattle.

  3. Ground-water quality atlas of Wisconsin

    USGS Publications Warehouse

    Kammerer, Phil A.

    1981-01-01

    This report summarizes data on ground-water quality stored in the U.S. Geological Survey's computer system (WATSTORE). The summary includes water quality data for 2,443 single-aquifer wells, which tap one of the State's three major aquifers (sand and gravel, Silurian dolomite, and sandstone). Data for dissolved solids, hardness, alkalinity, calcium, magnesium, sodium, potassium, iron, manganese, sulfate, chloride, fluoride, and nitrate are summarized by aquifer and by county, and locations of wells for which data are available 1 are shown for each aquifer. Calcium, magnesium, and bicarbonate (the principal component of alkalinity) are the major dissolved constituents in Wisconsin's ground water. High iron concentrations and hardness cause ground-water quality problems in much of the State. Statewide ,summaries of trace constituent (selected trace metals; arsenic, boron, and organic carbon) concentrations show that these constituents impair water quality in only a few isolated wells.

  4. Gebiss: an ImageJ plugin for the specification of ground truth and the performance evaluation of 3D segmentation algorithms

    PubMed Central

    2011-01-01

    Background Image segmentation is a crucial step in quantitative microscopy that helps to define regions of tissues, cells or subcellular compartments. Depending on the degree of user interactions, segmentation methods can be divided into manual, automated or semi-automated approaches. 3D image stacks usually require automated methods due to their large number of optical sections. However, certain applications benefit from manual or semi-automated approaches. Scenarios include the quantification of 3D images with poor signal-to-noise ratios or the generation of so-called ground truth segmentations that are used to evaluate the accuracy of automated segmentation methods. Results We have developed Gebiss; an ImageJ plugin for the interactive segmentation, visualisation and quantification of 3D microscopic image stacks. We integrated a variety of existing plugins for threshold-based segmentation and volume visualisation. Conclusions We demonstrate the application of Gebiss to the segmentation of nuclei in live Drosophila embryos and the quantification of neurodegeneration in Drosophila larval brains. Gebiss was developed as a cross-platform ImageJ plugin and is freely available on the web at http://imaging.bii.a-star.edu.sg/projects/gebiss/. PMID:21668958

  5. Ground-water data for Michigan 1986

    USGS Publications Warehouse

    Huffman, G.C.

    1988-01-01

    Water levels, locations, depths, and aquifers tapped are given for 112 observation wells. Tabulated data include extremes of water levels for calendar year 1986 and for the period of record, pumpage of most major groundwater users in the State, and water-quality data from selected wells. The largest reported user of ground-water, the city of Lansing, pumped 7.6 billion gallons from the Saginaw Formation and glacial deposits in 1986.

  6. Sonobuoy-Based, 3-D Acoustic Characterization of Shallow-Water Environments

    DTIC Science & Technology

    2015-09-30

    Shallow- Water Environments George V. Frisk Department of Ocean and Mechanical Engineering Florida Atlantic University SeaTech Campus 101 North Beach...TERM GOALS The long-term goal of this research is to increase our understanding of shallow water acoustic propagation and its relationship to the...three-dimensionally varying seabed and water column environments. OBJECTIVES The scientific objectives of this research are: (1) to develop high

  7. Coupling Between Microstrip Lines and Finite Ground Coplanar Lines Embedded in Polyimide Layers for 3D-MMICs on Silicon

    NASA Technical Reports Server (NTRS)

    Ponchak, G. E.; Bushyager, N.; Papapolymerou, J.; Tentzeris, E. M.; Laskar, J.

    2002-01-01

    Three-dimensional circuits built upon multiple layers of polyimide are required for constructing Si/SiGe monolithic microwave/mm-wave integrated circuits on CMOS (low resistivity) Si wafers. It is expected that these circuits will replace the ones fabricated on GaAs and reduce the overall system cost. However, the closely spaced transmission lines that are required for a high-density circuit environment are susceptible to high levels of cross-coupling, which degrades the overall circuit performance. In this paper, theoretical and experimental results on coupling and ways to reduce it are presented for two types of transmission lines: a) the microstrip line and b) the Finite Ground Coplanar (FGC) line. For microstrip lines it is shown that a fence of metalized via-holes can significantly reduce coupling, especially in the case when both lines are on the same polyimide layer or when the shielding structure extends through several polyimide layers. For closely spaced microstrip lines, coupling is lower for a metal filled trench shield than a via-hole fence. Coupling amongst microstrip lines is dependent on the ratio of line separation to polyimide thickness and is primarily due to magnetic fields. For FGC lines it is shown that they have in general low coupling that can be reduced significantly when there is even a small gap between the ground planes of each line. FGC lines have approximately 8 dB lower coupling than coupled coplanar waveguides (CPW). In addition, forward and backward characteristics of the FGC lines do not resemble those of other transmission lines such as microstrip. Therefore, the coupling mechanism of the FGC lines is different compared to thin film microstrip lines.

  8. Comparison of ground-based UV irradiance measurements with satellite-derived values and 1-D- and 3-D-radiative transfer model calculations in mountainous terrain

    NASA Astrophysics Data System (ADS)

    Wagner, J. E.; Arola, A.; Blumthaler, M.; Fitzka, M.; Kift, R.; Kreuter, A.; Rieder, H. E.; Simic, S.; Webb, A.; Weihs, P.

    2009-04-01

    Since the discovery of anthropogenic ozone depletion more than 30 year ago, the scientific community has shown an increasing interest in UV-B radiation. Nowadays, ground-based high quality measurements of spectrally resolved UV-radiation are available. On the other hand, 1-D- and 3-D models have been developed, that describe the radiative transfer through the atmosphere physically very accurately. Another approach for determining the UV-irradiance at the surface of the earth is the use of satellite-based reflectance measurements as input for retrieval algorithms. At the moment, the research focuses on the impact of clouds on UV-radiation, but the impact of mountains on UV-radiation, especially in combination with high surface albedo due to snowcover, is also very strong and detailed comparisons between measurements and modelling are lacking. Therefore, three measurement campaigns had been conducted in alpine areas of Austria (Innsbruck and Hoher Sonnblick). The goal was to investigate the impact of alpine terrain in combination with snowcover on spectral UV-irradiance and actinic flux. This contribution uses the ground-based UV-irradiance measurements to evaluate three different UV-irradiance calculation methods. Results from three different calculation methods (satellite retrieval, 1-D- and 3-D radiative transfer model) for UV radiation in terms of UV-Index, erythemally weighted daily doses and spectrally resolved UV-Irradiance at 305, 310, 324 and 380nm are presented and compared with ground-based high quality measurements. The real case study is performed in very inhomogenous terrain under clear sky conditions. The values of the different methods are not only compared for the measurements sites, but additionally the impact of altitude is investigated. So far it seems, that 1-D simulations show the best agreement (±10%) with the measurements whereas the 3-D model simulations and satellite retrieved values differ much more. Satellite retrieved values

  9. Transverse instability and viscous dissipation of forced 3-D gravity-capillary solitary waves on deep water

    NASA Astrophysics Data System (ADS)

    Cho, Yeunwoo

    2014-11-01

    The shedding phenomena of 3-D viscous gravity-capillary solitary waves generated by a moving air-forcing on the surface of deep water are investigated. Near the resonance where the forcing speed is close to 23 cm/s, two kinds of shedding modes are possible; Anti-symmetric and symmetric modes. A relevant theoretical model equation is numerically solved for the identification of shedding of solitary waves, and is analytically studied in terms of their linear stability to transverse perturbations. Furthermore, by tracing trajectories of shed solitary waves, the decay rate of a 3-D solitary wave due to viscous dissipation is estimated. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2014R1A1A1002441).

  10. 3D Printing of Cytocompatible Water-Based Light-Cured Polyurethane with Hyaluronic Acid for Cartilage Tissue Engineering Applications

    PubMed Central

    Shie, Ming-You; Chang, Wen-Ching; Wei, Li-Ju; Huang, Yu-Hsin; Chen, Chien-Han; Shih, Cheng-Ting; Chen, Yi-Wen; Shen, Yu-Fang

    2017-01-01

    Diseases in articular cartilages have affected millions of people globally. Although the biochemical and cellular composition of articular cartilages is relatively simple, there is a limitation in the self-repair ability of the cartilage. Therefore, developing strategies for cartilage repair is very important. Here, we report on a new liquid resin preparation process of water-based polyurethane based photosensitive materials with hyaluronic acid with application of the materials for 3D printed customized cartilage scaffolds. The scaffold has high cytocompatibility and is one that closely mimics the mechanical properties of articular cartilages. It is suitable for culturing human Wharton’s jelly mesenchymal stem cells (hWJMSCs) and the cells in this case showed an excellent chondrogenic differentiation capacity. We consider that the 3D printing hybrid scaffolds may have potential in customized tissue engineering and also facilitate the development of cartilage tissue engineering. PMID:28772498

  11. Ground-water data for Michigan, 1976

    USGS Publications Warehouse

    Huffman, G.C.

    1977-01-01

    The purpose of this report is to make available the records of water levels in principal aquifers of the State through 1976 and to compile related data, such as records of ground-water pumpage. Also included in the report are data on municipal, public, and industrial water-supply facilities. Records of water levels in areas of heavy pumpage and in areas where changes are principally due to natural influences are illustrated or tabulated to allow comparison between these types of water-level fluctuations. Water levels and related data provide a record for the evaluation of available ground-water supplies. The long-term records serve as a framework to which short-term records may be related. This report is written for persons, municipalities, industries, institutions, consultants, drillers, and hydrologists interested in the groundwater resources of the State.

  12. Fabrication of scalable and structured tissue engineering scaffolds using water dissolvable sacrificial 3D printed moulds.

    PubMed

    Mohanty, Soumyaranjan; Larsen, Layla Bashir; Trifol, Jon; Szabo, Peter; Burri, Harsha Vardhan Reddy; Canali, Chiara; Dufva, Marin; Emnéus, Jenny; Wolff, Anders

    2015-10-01

    One of the major challenges in producing large scale engineered tissue is the lack of ability to create large highly perfused scaffolds in which cells can grow at a high cell density and viability. Here, we explore 3D printed polyvinyl alcohol (PVA) as a sacrificial mould in a polymer casting process. The PVA mould network defines the channels and is dissolved after curing the polymer casted around it. The printing parameters determined the PVA filament density in the sacrificial structure and this density resulted in different stiffness of the corresponding elastomer replica. It was possible to achieve 80% porosity corresponding to about 150 cm(2)/cm(3) surface to volume ratio. The process is easily scalable as demonstrated by fabricating a 75 cm(3) scaffold with about 16,000 interconnected channels (about 1m(2) surface area) and with a channel to channel distance of only 78 μm. To our knowledge this is the largest scaffold ever to be produced with such small feature sizes and with so many structured channels. The fabricated scaffolds were applied for in-vitro culturing of hepatocytes over a 12-day culture period. Smaller scaffolds (6×4 mm) were tested for cell culturing and could support homogeneous cell growth throughout the scaffold. Presumably, the diffusion of oxygen and nutrient throughout the channel network is rapid enough to support cell growth. In conclusion, the described process is scalable, compatible with cell culture, rapid, and inexpensive.

  13. Ground Water Technical Support Center (GWTSC) Annual ...

    EPA Pesticide Factsheets

    The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA’s National Risk Management Research Laboratory (NRMRL). The GWTSC is one of an interlinked group of specialized Technical Support Centersthat were established under the Technical Support Project (TSP). The GWTSC provides technical support on issues related to groundwater. Specifically, the GWTSC provides technical support to U.S. EPA and State regulators for issues and problems related to:1. subsurface contamination (contaminants in ground water, soils and sediments),2. cross-media transfer (movement of contaminants from the subsurface to other media such as surface water or air), and3. restoration of impacted ecosystems.The GWTSC works with Remedial Project Managers (RPMs) and other decision makers to solve specific problems at Superfund, RCRA (Resource Conservation and Recovery Act), Brownfields sites, and ecosystem restoration sites. The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA’s National Risk Management Research Laboratory (NRMRL). The GWTSC is one of an interlinked group of specialized Technical Suppo

  14. Ground Water Discharges (EPA's Underground Injection ...

    EPA Pesticide Factsheets

    2017-07-06

    Most ground water used for drinking occurs near the earth's surface and is easily contaminated. Of major concern is the potential contamination of underground sources of drinking water by any of the hundreds of thousands of subsurface wastewater disposal injection wells nationwide.

  15. Ground Water Flow No Longer A Mystery

    ERIC Educational Resources Information Center

    Lehr, Jay H.; Pettyjohn, Wayne A.

    1976-01-01

    Examined are the physical characteristics of ground water movement. Some potential pollution problems are identified. Models are used to explain mathematical and hydraulic principles of flow toward a pumping well and an effluent stream, flow around and through lenticular beds, and effects of pumping on the water table. (Author/MR)

  16. Ground Water Flow No Longer A Mystery

    ERIC Educational Resources Information Center

    Lehr, Jay H.; Pettyjohn, Wayne A.

    1976-01-01

    Examined are the physical characteristics of ground water movement. Some potential pollution problems are identified. Models are used to explain mathematical and hydraulic principles of flow toward a pumping well and an effluent stream, flow around and through lenticular beds, and effects of pumping on the water table. (Author/MR)

  17. Ground-water data for Michigan, 1980

    USGS Publications Warehouse

    Huffman, G.C.

    1981-01-01

    The purpose of this report is to make available the 1980 records of water levels and related data for the principal aquifers of the State. This report is written for municipalities, industries, institutions, consultants, drillers, hydrologists and other people interested in the ground-water resources.

  18. Ground-water data for Michigan 1979

    USGS Publications Warehouse

    Huffman, G.C.

    1980-01-01

    The purpose of this report is to make available the 1979 records of water levels and related data for the principal aquifers of the State. This report is written for municipalities, industries, institutions, consultants, drillers, hydrologists, and other people interested in the ground-water resources.

  19. Ground-water data for Michigan, 1978

    USGS Publications Warehouse

    Huffman, G.C.

    1979-01-01

    The purpose of this report is to make available the 1978 records of water levels and related data for the principal aquifers of the State. This report is written for municipalities, industries, institutions, consultants, drillers, hydrologists, and other people interested in the ground-water resources of the State.

  20. Ground-water control of evaporite deposition

    USGS Publications Warehouse

    Wood, W.W.; Sanford, W.E.

    1990-01-01

    The ratio of ground-water outflow to inflow (flux ratio) in hydrologically open basins is as important in determining the mineralogy and thicknesses of evaporite deposits as the solute composition of the inflow water. Attainment of steady state flux ratios permits large thicknesses of two or three minerals to form rather than thin veneers of many minerals. -from Authors

  1. Rapid whole cerebrum myelin water imaging using a 3D GRASE sequence.

    PubMed

    Prasloski, Thomas; Rauscher, Alexander; MacKay, Alex L; Hodgson, Madeleine; Vavasour, Irene M; Laule, Corree; Mädler, Burkhard

    2012-10-15

    Myelin water imaging, a magnetic resonance imaging technique capable of resolving the fraction of water molecules which are located between the layers of myelin, is a valuable tool for investigating both normal and pathological brain structure in vivo. There is a strong need for pulse sequences which improve the quality and applicability of myelin water imaging in a clinical setting. In this study, we validated the use of a fast multi echo T(2) relaxation sequence for myelin water imaging. Using a multiple combined gradient and spin echo (GRASE) technique, we attain whole cerebrum myelin water images in under 15 minutes. Region of interest analysis indicates that this fast GRASE imaging sequence produces results which are in good agreement with pure spin echo measurements (R(2)=0.95, p<0.0001). This drastic improvement in speed and brain coverage compared to current spin echo standards will allow increased inclusion of myelin water imaging in neurological research protocols and opens up the possibility of applications in a clinical setting.

  2. Ground water and surface water; a single resource

    USGS Publications Warehouse

    Winter, Thomas C.; Harvey, Judson W.; Franke, O. Lehn; Alley, William M.

    1998-01-01

    The importance of considering ground water and surface water as a single resource has become increasingly evident. Issues related to water supply, water quality, and degradation of aquatic environments are reported on frequently. The interaction of ground water and surface water has been shown to be a significant concern in many of these issues. Contaminated aquifers that discharge to streams can result in long-term contamination of surface water; conversely, streams can be a major source of contamination to aquifers. Surface water commonly is hydraulically connected to ground water, but the interactions are difficult to observe and measure. The purpose of this report is to present our current understanding of these processes and activities as well as limitations in our knowledge and ability to characterize them.

  3. 3D imaging of the internal structure of a rock-cored drumlin using ground-penetrating radar

    NASA Astrophysics Data System (ADS)

    King, Edward; Spagnolo, Matteo; Rea, Brice; Ely, Jeremy; Lee, Joshua

    2016-04-01

    One key question linking subglacial bedform analyses to ice dynamics relates to the flux of sediment at the bed. It is relatively easy to measure the upper surface of subglacial sediments either in active contemporary systems (using ice-penetrating radar surveys) or in relict subglacial terrain (using high-resolution digital elevation models). However, constraining the lower surface of subglacial sediments, i.e. the contact between the bedform sediment and a lower sediment unit or bedrock, is much more difficult, yet it is crucial to any determination of sediment volume and hence flux. Without observations, we are reliant on assumptions about the nature of the lower sediment surface. For example, we might assume that all the drumlins in a particular drumlin field are deposited on a planar surface, or that all comprise a carapace of till over a rock core. A calculation of sediment volume will give very different results leading to very different interpretations of sediment flux. We have been conducting experiments in the use of ground-penetrating radar to find the lower sedimentary surface beneath drumlins near Kirkby Stephen (Northern England), part of the extensive Eden Valley drumlin field. The drumlins comprise diamict overlying a bedrock surface of Carboniferous limestone which outcrops frequently between the drumlins. Here we present the results of a grid survey over one of the drumlins that clearly demonstrate this drumlin comprises a thin carapace of till overlying a stepped limestone bedrock surface. We provide details on the field data acquisition parameters and discuss the implications for further geophysical studies of drumlin fields.

  4. Recharge estimation for transient ground water modeling.

    PubMed

    Jyrkama, Mikko I; Sykes, Jon F; Normani, Stefano D

    2002-01-01

    Reliable ground water models require both an accurate physical representation of the system and appropriate boundary conditions. While physical attributes are generally considered static, boundary conditions, such as ground water recharge rates, can be highly variable in both space and time. A practical methodology incorporating the hydrologic model HELP3 in conjunction with a geographic information system was developed to generate a physically based and highly detailed recharge boundary condition for ground water modeling. The approach uses daily precipitation and temperature records in addition to land use/land cover and soils data. The importance of the method in transient ground water modeling is demonstrated by applying it to a MODFLOW modeling study in New Jersey. In addition to improved model calibration, the results from the study clearly indicate the importance of using a physically based and highly detailed recharge boundary condition in ground water quality modeling, where the detailed knowledge of the evolution of the ground water flowpaths is imperative. The simulated water table is within 0.5 m of the observed values using the method, while the water levels can differ by as much as 2 m using uniform recharge conditions. The results also show that the combination of temperature and precipitation plays an important role in the amount and timing of recharge in cooler climates. A sensitivity analysis further reveals that increasing the leaf area index, the evaporative zone depth, or the curve number in the model will result in decreased recharge rates over time, with the curve number having the greatest impact.

  5. Iowa ground-water quality

    USGS Publications Warehouse

    Buchmiller, R.C.; Squillace, P.J.; Drustrup, R.D.

    1987-01-01

    The U.S. Geological Survey, in cooperation with the University of Iowa Hygienic Laboratory, the Iowa Department of Natural Resources, and several counties in Iowa, currently (1986) is monitoring about 1,500 public and private wells for inorganic and organic constituents. The principal objective of this program, begun in 1982, is to collect water-quality data that will describe the long-term chemical quality of the surficial and major bedrock aquifer systems in Iowa (Detroy, 1985).

  6. Ground-water data for Michigan, 1981

    USGS Publications Warehouse

    Huffman, G.C.

    1982-01-01

    This report summarizes data on water levels in 124 observation wells and provides information on well locations, depths, altitudes, and aquifers that they tap. Tabulated data include extremes of water levels for 1981 and for the period of record; pumpage of most major groundwater users in the State; and quality data on selected wells. The city of Lansing was the largest reported user of ground-water, pumping 8.6 billion gallons from the Saginaw Formation and glacial deposits.

  7. High Plains regional ground-water study

    USGS Publications Warehouse

    Dennehy, Kevin F.

    2000-01-01

    Over the last 25 years, industry and government have made large financial investments aimed at improving water quality across the Nation. Significant progress has been made; however, many water-quality concerns remain. In 1991, the U.S. Geological Survey (USGS) began implementing a full-scale National Water-Quality Assessment Program to provide consistent and scientifically sound information for managing the Nation's water resources. The goals of the NAWQA Program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers, (2) describe how water quality is changing over time, and (3) improve our understanding of the primary natural and human factors affecting water quality. Assessing the quality of water in every location in the Nation would not be practical; therefore, NAWQA Program studies are conducted within a set of areas called study units (fig. 1). These study units are composed of more than 50 important river and aquifer systems that represent the diverse geography, water resources, and land and water uses of the Nation. The High Plains Regional Ground-Water Study is one such study area, designed to address issues relevant to the High Plains Aquifer system while supplementing water-quality information collected in other study units across the Nation. Implementation of the NAWQA Program for the High Plains Regional Ground-Water Study area began in 1998.

  8. Water rights in areas of ground-water mining

    USGS Publications Warehouse

    Thomas, Harold E.

    1955-01-01

    Ground-water mining, the progressive depletion of storage in a ground-water reservoir, has been going on for several years in some areas, chiefly in the Southwestern States. In some of these States a water right is based on ownership of land overlying the ground-water reservoir and does not depend upon putting the water to use; in some States a right is based upon priority of appropriation and use and may be forfeited if the water is allowed to go unused for a specified period, but ownership of land is not essential; and in several States both these doctrines or modifications thereof are accepted, and each applies to certain classes of water or to certain conditions of development.Experience to date indicates that a cure for ground-water mining does not necessarily depend upon the water-rights doctrine that is accepted in the area. Indeed, some recent court decisions have incorporated both the areal factor of the landownership doctrines and the time factor of the appropriation doctrine. Overdraft can be eliminated if water is available from another source to replace some of the water taken from the affected aquifer. In areas where no alternate source of supply is available at reasonable cost, public opinion so far appears to favor treating ground water as a nonrenewable resource comparable to petroleum and metals, and mining it until the supply is exhausted, rather than curbing the withdrawals at an earlier date.

  9. Water-repellent coatings for surface and 3D wood processing

    NASA Astrophysics Data System (ADS)

    Debelova, N. N.; Gorlenko, N. P.; Volokitin, G. G.; Sarkisov, Yu S.; Dmitriyenko, V. P.; Zavyalova, E. N.; Zavyalov, P. B.

    2015-01-01

    The paper presents the results of research in organic chemical compositions for hydrophobic protection of wood with the use of surface and three-dimensional coating techniques of impregnation and chemical compositions. Water absorption indicators, angles of contact on the surface of treated samples are detected herein. Kinetic equation of the moisture diffusion transition in capillary-porous structure of wood is suggested.

  10. A molecular dynamics implementation of the 3D Mercedes-Benz water model

    NASA Astrophysics Data System (ADS)

    Hynninen, T.; Dias, C. L.; Mkrtchyan, A.; Heinonen, V.; Karttunen, M.; Foster, A. S.; Ala-Nissila, T.

    2012-02-01

    The three-dimensional Mercedes-Benz model was recently introduced to account for the structural and thermodynamic properties of water. It treats water molecules as point-like particles with four dangling bonds in tetrahedral coordination, representing H-bonds of water. Its conceptual simplicity renders the model attractive in studies where complex behaviors emerge from H-bond interactions in water, e.g., the hydrophobic effect. A molecular dynamics (MD) implementation of the model is non-trivial and we outline here the mathematical framework of its force-field. Useful routines written in modern Fortran are also provided. This open source code is free and can easily be modified to account for different physical context. The provided code allows both serial and MPI-parallelized execution. Program summaryProgram title: CASHEW (Coarse Approach Simulator for Hydrogen-bonding Effects in Water) Catalogue identifier: AEKM_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKM_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 20 501 No. of bytes in distributed program, including test data, etc.: 551 044 Distribution format: tar.gz Programming language: Fortran 90 Computer: Program has been tested on desktop workstations and a Cray XT4/XT5 supercomputer. Operating system: Linux, Unix, OS X Has the code been vectorized or parallelized?: The code has been parallelized using MPI. RAM: Depends on size of system, about 5 MB for 1500 molecules. Classification: 7.7 External routines: A random number generator, Mersenne Twister ( http://www.math.sci.hiroshima-u.ac.jp/m-mat/MT/VERSIONS/FORTRAN/mt95.f90), is used. A copy of the code is included in the distribution. Nature of problem: Molecular dynamics simulation of a new geometric water model. Solution method: New force-field for

  11. 3D basin-shape ratio effects on frequency content and spectral amplitudes of basin-generated surface waves and associated spatial ground motion amplification and differential ground motion

    NASA Astrophysics Data System (ADS)

    Kamal; Narayan, J. P.

    2015-04-01

    This paper presents the effects of basin-shape ratio (BSR) on the frequency content and spectral amplitudes of the basin-generated surface (BGS) waves and the associated spatial variation of ground motion amplification and differential ground motion (DGM) in a 3D semi-spherical (SS) basin. Seismic responses were computed using a recently developed 3D fourth-order spatial accurate time-domain finite-difference (FD) algorithm based on the parsimonious staggered-grid approximation of the 3D viscoelastic wave equations. The simulated results revealed the decrease of both the frequency content and the spectral amplitudes of the BGS waves and the duration of ground motion in the SS basin with the decrease of BSR. An increase of the average spectral amplification (ASA), DGM and the average aggravation factor (AAF) towards the centre of the SS basin was obtained due to the focusing of the surface waves. A decrease of ASA, DGM and AAF with the decrease of BSR was also obtained.

  12. Flexible 3D Nanoporous Graphene for Desalination and Bio-decontamination of Brackish Water via Asymmetric Capacitive Deionization.

    PubMed

    El-Deen, Ahmed G; Boom, Remko M; Kim, Hak Yong; Duan, Hongwei; Chan-Park, Mary B; Choi, Jae-Hwan

    2016-09-28

    Nanoporous graphene based materials are a promising nanostructured carbon for energy storage and electrosorption applications. We present a novel and facile strategy for fabrication of asymmetrically functionalized microporous activated graphene electrodes for high performance capacitive desalination and disinfection of brackish water. Briefly, thiocarbohydrazide coated silica nanoparticles intercalated graphene sheets are used as a sacrificial material for creating mesoporous graphene followed by alkaline activation process. This fabrication procedure meets the ideal desalination pore diameter with ultrahigh specific surface area ∼ 2680 m(2) g(-1) of activated 3D graphene based micropores. The obtained activated graphene electrode is modified by carboxymethyl cellulose as negative charge (COO(-2)) and disinfectant quaternary ammonium cellulose with positively charged polyatomic ions of the structure (NR4(+)). Our novel asymmetric coated microporous activated 3D graphene employs nontoxic water-soluble binder which increases the surface wettability and decreases the interfacial resistance and moreover improves the electrode flexibility compared with organic binders. The desalination performance of the fabricated electrodes was evaluated by carrying out single pass mode experiment under various cell potentials with symmetric and asymmetric cells. The asymmetric charge coated microporous activated graphene exhibits exceptional electrosorption capacity of 18.43 mg g(-1) at a flow rate of 20 mL min(-1) upon applied cell potential of 1.4 V with initial NaCl concentration of 300 mg L(-1), high charge efficiency, excellent recyclability, and, moreover, good antibacterial behavior. The present strategy provides a new avenue for producing ultrapure water via green capacitive deionization technology.

  13. Effect of 3-D instrument casing shape on the self-shading of in-water upwelling irradiance.

    PubMed

    Piskozub, Jacek

    2004-07-12

    The self-shading measurement error of the upwelling irradiance caused by the presence of a typical cylindrical housing of an optical instrument was calculated with the 3-D Monte-Carlo code as a function of the housing dimensions and of the optical parameters of seawater. The resulting values were compared to the self-shading error for a flat disk of the same diameter, originally used to establish self-shading error estimations universally used in marine optics. The results show that the self-shading of upwelling irradiance is underestimated by up to 25% producing a significant underestimation of the measured upwelling irradiance, and therefore reflectance, especially in turbid waters.

  14. Effect of 3-D instrument casing shape on the self-shading of in-water upwelling irradiance

    NASA Astrophysics Data System (ADS)

    Piskozub, Jacek

    2004-07-01

    The self-shading measurement error of the upwelling irradiance caused by the presence of a typical cylindrical housing of an optical instrument was calculated with the 3-D Monte-Carlo code as a function of the housing dimensions and of the optical parameters of seawater. The resulting values were compared to the self-shading error for a flat disk of the same diameter, originally used to establish self-shading error estimations universally used in marine optics. The results show that the self-shading of upwelling irradiance is underestimated by up to 25% producing a significant underestimation of the measured upwelling irradiance, and therefore reflectance, especially in turbid waters.

  15. Predicting Strong Ground-Motion Seismograms for Magnitude 9 Cascadia Earthquakes Using 3D Simulations with High Stress Drop Sub-Events

    NASA Astrophysics Data System (ADS)

    Frankel, A. D.; Wirth, E. A.; Stephenson, W. J.; Moschetti, M. P.; Ramirez-Guzman, L.

    2015-12-01

    We have produced broadband (0-10 Hz) synthetic seismograms for magnitude 9.0 earthquakes on the Cascadia subduction zone by combining synthetics from simulations with a 3D velocity model at low frequencies (≤ 1 Hz) with stochastic synthetics at high frequencies (≥ 1 Hz). We use a compound rupture model consisting of a set of M8 high stress drop sub-events superimposed on a background slip distribution of up to 20m that builds relatively slowly. The 3D simulations were conducted using a finite difference program and the finite element program Hercules. The high-frequency (≥ 1 Hz) energy in this rupture model is primarily generated in the portion of the rupture with the M8 sub-events. In our initial runs, we included four M7.9-8.2 sub-events similar to those that we used to successfully model the strong ground motions recorded from the 2010 M8.8 Maule, Chile earthquake. At periods of 2-10 s, the 3D synthetics exhibit substantial amplification (about a factor of 2) for sites in the Puget Lowland and even more amplification (up to a factor of 5) for sites in the Seattle and Tacoma sedimentary basins, compared to rock sites outside of the Puget Lowland. This regional and more localized basin amplification found from the simulations is supported by observations from local earthquakes. There are substantial variations in the simulated M9 time histories and response spectra caused by differences in the hypocenter location, slip distribution, down-dip extent of rupture, coherence of the rupture front, and location of sub-events. We examined the sensitivity of the 3D synthetics to the velocity model of the Seattle basin. We found significant differences in S-wave focusing and surface wave conversions between a 3D model of the basin from a spatially-smoothed tomographic inversion of Rayleigh-wave phase velocities and a model that has an abrupt southern edge of the Seattle basin, as observed in seismic reflection profiles.

  16. EPA GROUND WATER ISSUE: Ground Water Sample Preservation at ISCO Sites – Recommended Guidelines

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the introduction of a chemical oxidant into the subsurface for the purpose of transforming ground water contaminants into harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste sites may contai...

  17. EPA GROUND WATER ISSUE: Ground Water Sample Preservation at ISCO Sites – Recommended Guidelines

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the introduction of a chemical oxidant into the subsurface for the purpose of transforming ground water contaminants into harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste sites may contai...

  18. Ground-water situation in Oregon

    USGS Publications Warehouse

    Newcomb, R.C.

    1951-01-01

    The water that occurs beneath the land surface follows definite and well-known rules of hydraulics, the same as water on the surface. However, ground water must be studied by methods, some of which are unique to that type of water occurrence, in order to evaluate the part it plays in the over-all water scheme.Water that falls on the land surface as rain or snow and water that rests upon the surface may in places pass laterally or downward through the pores of the earth materials. There it may take one or more of a variety of paths before again flowing out on the surface or being expelled to the atmosphere by evaporation and by the transpiration of plants. Water so diverted underground is delayed or diverted from its course toward the sea and that digression results in many services of prime importance to mankind. Underground, the water generally exceeds in total quantity the water present on the land surface at any one time.The discussion of ground water can be clarified somewhat by a description of the major parts or phases of the normal path of water underground.

  19. Vanadium nanobelts coated nickel foam 3D bifunctional electrode with excellent catalytic activity and stability for water electrolysis

    NASA Astrophysics Data System (ADS)

    Yu, Yu; Li, Pei; Wang, Xiaofang; Gao, Wenyu; Shen, Zongxu; Zhu, Yanan; Yang, Shuliang; Song, Weiguo; Ding, Kejian

    2016-05-01

    Pursuit of highly active, stable and low-cost electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is the key point for large-scale water splitting. A vanadium nanobelts coating on a nickel foam (V/NF) is proposed as an excellent 3D bifunctional electrode for water electrolysis here, which exhibits high activities with overpotentials of 292 and 176 mV at 10 mA cm-2 for OER and HER, respectively. When employed as a bifunctional electrocatalyst in an alkaline water electrolyzer, a cell voltage of 1.80 V was required to achieve 20 mA cm-2 with a slight increase during a 24 h durability test. The existence of the appropriate amount of nitrogen and oxygen elements in the surface region of vanadium nanobelts is regarded to be responsible for the electrocatalytic activity.Pursuit of highly active, stable and low-cost electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is the key point for large-scale water splitting. A vanadium nanobelts coating on a nickel foam (V/NF) is proposed as an excellent 3D bifunctional electrode for water electrolysis here, which exhibits high activities with overpotentials of 292 and 176 mV at 10 mA cm-2 for OER and HER, respectively. When employed as a bifunctional electrocatalyst in an alkaline water electrolyzer, a cell voltage of 1.80 V was required to achieve 20 mA cm-2 with a slight increase during a 24 h durability test. The existence of the appropriate amount of nitrogen and oxygen elements in the surface region of vanadium nanobelts is regarded to be responsible for the electrocatalytic activity. Electronic supplementary information (ESI) available: More SEM, TEM images, XRD patterns, LSV curves, XPS spectra. See DOI: 10.1039/c6nr02395a

  20. Using High Frequency Focused Water-Coupled Ultrasound for 3-D Surface Depression Profiling

    NASA Technical Reports Server (NTRS)

    Roth, Don J.; Whalen, Mike F.; Hendricks, J. Lynne; Bodis, James R.

    1999-01-01

    Surface topography is an important variable in the performance of many industrial components and is normally measured with diamond-tip profilometry over a small area or using optical scattering methods for larger area measurement. A prior study was performed demonstrating that focused air-coupled ultrasound at 1 MHz was capable of profiling surfaces with 25 micron depth resolution and 400 micron lateral resolution over a 1.4 mm depth range. In this article, the question of whether higher-frequency focused water-coupled ultrasound can improve on these specifications is addressed. 10 and 25 MHz focused ultrasonic transducers were employed in the water-coupled mode. Time-of-flight images of the sample surface were acquired and converted to depth / surface profile images using the simple relation (d = V*t/2) between distance (d), time-of-flight (t), and the velocity of sound in water (V). Results are compared for the two frequencies used and with those from the 1 MHz air-coupled configuration.

  1. Enantiomeric two-fold interpenetrated 3D zinc(ii) coordination networks as a catalytic platform: significant difference between water within the cage and trace water in transesterification.

    PubMed

    Choi, Eunkyung; Ryu, Minjoo; Lee, Haeri; Jung, Ok-Sang

    2017-04-05

    Self-assembly of Zn(ClO4)2 with 1,1,2,2-tetramethyl-1,2-di(pyridin-3-yl)disilane (L) as a bidentate N-donor gives rise to 3D coordination networks, [Zn(μ-OH)(L)]3(ClO4)3·5H2O (1·5H2O), of unique, 10(3)-a srs net topology. An important feature is that two enantiomeric 3D frameworks, 4(1)- and 4(3)-[Zn(μ-OH)(L)]3(ClO4)3·5H2O, are interpenetrated to form a racemic two-fold 3D network with cages occupied by two water molecules. Another structural characteristic is a C3-symmetric planar Zn3(μ-OH)3 6-membered ring with tetrahedral Zn(ii) ions. The steric hindrance of substrates and trace water effects on transesterification catalysis using the network have been scrutinized. The coordination network acts as a remarkable heterogeneous transesterification catalytic system that shows both the significant steric effects of substrate alcohols and momentous water effects. The substrate activity is in the order ethanol > n-propanol > n-butanol > iso-propanol > 2-butanol > tert-butanol. For the reaction system, solvate water molecules within the cages of the interpenetrated 3D frameworks do not decrease the transesterification activity, whereas the trace water molecules in the substrate alcohols act as obvious obstacles to the reaction.

  2. Ground-Water Data for Georgia, 1988

    USGS Publications Warehouse

    Joiner, Charles N.; Peck, Michael F.; Reynolds, Mark S.; Stayton, Welby L.

    1989-01-01

    Continuous water-level records from 144 wells and water-level measurements from an additional 617 wells in Georgia during 1988 provide the basic data for this report. Daily mean water-level hydrographs for selected wells illustrate the effects that changes ln recharge and discharge have had on the ground-water reservoirs in the State during 1988. Monthly mean water levels are shown for the 10-year period 1979-88. Maps showing the potentiometric surface of the Upper Floridan aquifer for Hay 1988 and the Claiborne and Clayton aquifers for October 1988 also are presented. Annual mean water levels in Georgia generally were below those measured in 1987; water levels ranged from 6.9 feet higher to 7.3 feet lower. Record-low water levels were measured during the last half of 1988 in 18 wells tapping the crystalline rock aquifer, the Cretaceous rock aquifer system, the Midville aquifer system, and the Clayton, Upper Floridan, and upper Brunswick aquifers. These record lows were from 0.1 to 1.4 feet lower than the previous record lows. A prolonged drought resulted in decreased recharge to the aquifers and increased ground-water pumping, which caused water levels to decline. Water-quality samples collected periodically throughout Georgia are analyzed as part of areal and regional ground-water studies. Maps showing chloride concentrations in the Upper Floridan aquifer in October 1988 in coastal Georgia and in the Savannah and Brunswick areas are presented. Periodic monitoring of water quality in the Savannah and Brunswick areas indicates that chloride concentrations in the Upper Floridan generally have remained stable.

  3. Sensitivity analysis for the total nitrogen pollution of the Danjiangkou Reservoir based on a 3-D water quality model

    NASA Astrophysics Data System (ADS)

    Chen, Libin; Yang, Zhifeng; Liu, Haifei

    2017-06-01

    Inter-basin water transfers containing a great deal of nitrogen are great threats to human health, biodiversity, and air and water quality in the recipient area. Danjiangkou Reservoir, the source reservoir for China's South-to-North Water Diversion Middle Route Project, suffers from total nitrogen pollution and threatens the water transfer to a number of metropolises including the capital, Beijing. To locate the main source of nitrogen pollution into the reservoir, especially near the Taocha canal head, where the intake of water transfer begins, we constructed a 3-D water quality model. We then used an inflow sensitivity analysis method to analyze the significance of inflows from each tributary that may contribute to the total nitrogen pollution and affect water quality. The results indicated that the Han River was the most significant river with a sensitivity index of 0.340, followed by the Dan River with a sensitivity index of 0.089, while the Guanshan River and the Lang River were not significant, with the sensitivity indices of 0.002 and 0.001, respectively. This result implies that the concentration and amount of nitrogen inflow outweighs the geographical position of the tributary for sources of total nitrogen pollution to the Taocha canal head of the Danjiangkou Reservoir.

  4. A 3-D hydrologic transport model of a water recharge system using carbamazepine and chloride as tracers

    NASA Astrophysics Data System (ADS)

    Rona, Michael; Gasser, Guy; Negev, Ido; Pankratov, Irena; Elhanany, Sara; Lev, Ovadia; Gvirtzman, Haim

    2014-05-01

    Wastewater recharge facilities are often used as a final water treatment before the discharge to the sea or before water reclamation. These facilities are often located in active aquifers that supply drinking water. Thus, leakage from the water recharge facility and gradual expansion of the underground wastewater plume are of considerable health concern. Hydrological modeling of water recharge systems are widely used as operational and predictive tools. These models rely on distributed water head monitoring and at least one chemical or physical tracer to model solutes' transport. Refractory micropollutants have proven useful in qualitative identification of pollution leakages and for quantification of pollution to a specific site near water recharge facilities. However, their usefulness as tracers for hydrological modeling is still questionable. In this article, we describe a long term, 3-D hydraulic model of a large-scale wastewater effluents recharge system in which a combination of chloride and a refractory micropollutant, carbamazepine is used to trace the solute transport. The combination of the two tracers provides the model with the benefits of the high specificity of the carbamazepine and the extensive historic data base that is available for chloride. The model predicts westward expansion of the pollution plume, whereas a standing front is formed at the east. These trends can be confirmed by the time trace of the carbamazepine concentrations at specific locations. We show that the combination of two tracers accounts better (at least at some locations) for the evolution of the pollution plume than a model based on chloride or carbamazepine alone.

  5. 3D magnetic resonance imaging as a non-invasive tool for investigating water-filled karst formations

    NASA Astrophysics Data System (ADS)

    Legchenko, A.; Ezersky, M.; Boucher, M.; Chevalier, A.; Vouillamoz, J.-M.

    2012-04-01

    Magnetic Resonance Sounding (MRS) is a geophysical technique developed for groundwater exploration. MRS can be used for reliable identification of karst aquifers because of the relaxation time of the magnetic resonance signal (T1) is longer for bulk water in karst caverns and channels (about 2 s) than for water in porous rock (few tens of ms). MRS is sensitive primary to groundwater volume but electrically conductive layers modify electromagnetic fields in the subsurface and thus may have an effect on MRS performance. Generally, the study of a karst requires a 3D field set-up and we developed a measuring procedure and interpretation software that makes it possible to image heterogeneous water-bearing geological formations down to about 80 m (3D-SNMR method). Numerical modeling results show that limited resolution of the method allows only identification of large karst formations. For example detectable karst should be larger than a few hundred cubic meters when karst is located close to the surface and a few thousand cubic meters when it is located at 60 m. Time Domain Electromagnetic method (TDEM) is known as an efficient tool for investigating electrical conductivity of rocks. TDEM results allow more accurate computing of the EM field in the subsurface and thus contribute for improving accuracy of MRS results. TDEM and 3D-SNMR methods were applied jointly in the Dead Sea coast of Israel (Nahal Hever South). The subsurface in this area is heterogeneous and composed of intercalated sand and clay layers over a salt rock, which is partly karstified. Groundwater is very saline, with a chloride concentration of 100-225 g/l thus rendering the resistivity of geological formations less than 1 ohm-m. We have shown numerically that under Dead Sea coast conditions, 3D-SNMR is able to detect and to locate the target within an error of a few tens of meters. In the investigated area (500×500 m2) our results reveal a very heterogeneous shallow aquifer that could be divided into

  6. Tools to Perform Local Dense 3D Reconstruction of Shallow Water Seabed.

    PubMed

    Avanthey, Loïca; Beaudoin, Laurent; Gademer, Antoine; Roux, Michel

    2016-05-17

    Tasks such as distinguishing or identifying individual objects of interest require the production of dense local clouds at the scale of these individual objects of interest. Due to the physical and dynamic properties of an underwater environment, the usual dense matching algorithms must be rethought in order to be adaptive. These properties also imply that the scene must be observed at close range. Classic robotized acquisition systems are oversized for local studies in shallow water while the systematic acquisition of data is not guaranteed with divers. We address these two major issues through a multidisciplinary approach. To efficiently acquire on-demand stereoscopic pairs using simple logistics in small areas of shallow water, we devised an agile light-weight dedicated system which is easy to reproduce. To densely match two views in a reliable way, we devised a reconstruction algorithm that automatically accounts for the dynamics, variability and light absorption of the underwater environment. Field experiments in the Mediterranean Sea were used to assess the results.

  7. Tools to Perform Local Dense 3D Reconstruction of Shallow Water Seabed ‡

    PubMed Central

    Avanthey, Loïca; Beaudoin, Laurent; Gademer, Antoine; Roux, Michel

    2016-01-01

    Tasks such as distinguishing or identifying individual objects of interest require the production of dense local clouds at the scale of these individual objects of interest. Due to the physical and dynamic properties of an underwater environment, the usual dense matching algorithms must be rethought in order to be adaptive. These properties also imply that the scene must be observed at close range. Classic robotized acquisition systems are oversized for local studies in shallow water while the systematic acquisition of data is not guaranteed with divers. We address these two major issues through a multidisciplinary approach. To efficiently acquire on-demand stereoscopic pairs using simple logistics in small areas of shallow water, we devised an agile light-weight dedicated system which is easy to reproduce. To densely match two views in a reliable way, we devised a reconstruction algorithm that automatically accounts for the dynamics, variability and light absorption of the underwater environment. Field experiments in the Mediterranean Sea were used to assess the results. PMID:27196913

  8. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) to prevent contamination of samples and the ground water. ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A...

  9. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of...

  10. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  11. Summary appraisals of the Nation's ground-water resources; Alaska

    USGS Publications Warehouse

    Zenone, Chester; Anderson, Gary S.

    1978-01-01

    Present deficiencies in the ground-water information base are obvious limiting factors to ground-water development in Alaska. There is a need to extend the ground-water data-collection network and to pursue special research into the quantitative aspects of ground-water hydrology in cold regions, particularly the continuous permafrost zone.

  12. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of...

  13. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Ground-water monitoring systems. 258.51... FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of...

  14. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Ground-water monitoring systems. 257.22... Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number of...

  15. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of...

  16. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  17. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  18. 3D Dynamic Rupture process ans Near Source Ground Motion Simulation Using the Discrete Element Method: Application to the 1999 Chi-chi and 2000 Tottori Earthquakes

    NASA Astrophysics Data System (ADS)

    Dalguer Gudiel, L. A.; Irikura, K.

    2001-12-01

    We performed a 3D model to simulate the dynamic rupture of a pre-existing fault and near-source ground motion of actual earthquakes solving the elastodynamic equation of motion using the 3D Discrete Element Method (DEM). The DEM is widely employed in engineering to designate lumped mass models in a truss arrangement, as opposed to FEM (Finite Element) models that may also consist of lumped masses, but normally require to mount a full stiffness matrix for response determination. The term has also been used for models of solids consisting of assemblies of discrete elements, such as spheres in elastic contact, employed in the analysis of perforation or penetration of concrete or rock. It should be noted that the designation Lattice Models, common in Physics, may be more adequate, although it omits reference to a fundamental property of the approach, which is the lumped-mass representation. In the present DEM formulation, the method models any orthotropic elastic solid. It is constructed by a three dimensional periodic truss-like structures using cubic elements that consists of lumping masses in nodal points, which are interconnected by unidimensional elements. The method was previously used in 2D to simulate in a simplified way the 1999 Chi-chi (Taiwan) earthquake (Dalguer et. al., 2000). Now the method was extended to resolve 3D problems. We apply the model to simulate the dynamic rupture process and near source ground motion of the 1999 Chi-chi (Taiwan) and the 2000 Tottori (Japan) earthquakes. The attractive feature in the problem under consideration is the possibility of introducing internal cracks or fractures with little computational effort and without increasing the number of degrees of freedom. For the 3D dynamic spontaneous rupture simulation of these eartquakes we need to know: the geometry of the fault, the initial stress distribution along the fault, the stress drop distribution, the strength of the fault to break and the critical slip (because slip

  19. Developing an integrated 3D-hydrodynamic and emerging contaminant model for assessing water quality in a Yangtze Estuary Reservoir.

    PubMed

    Xu, Cong; Zhang, Jingjie; Bi, Xiaowei; Xu, Zheng; He, Yiliang; Gin, Karina Yew-Hoong

    2017-12-01

    An integrated 3D-hydrodynamic and emerging contaminant model was developed for better understanding of the fate and transport of emerging contaminants in Qingcaosha Reservoir. The reservoir, which supplies drinking water for nearly half of Shanghai's population, is located in Yangtze Delta. The integrated model was built by Delft3D suite, a fully integrated multidimensional modeling software. Atrazine and Bisphenol A (BPA) were selected as two representative emerging contaminants for the study in this reservoir. The hydrodynamic model was calibrated and validated against observations from 2011 to 2015 while the integrated model was calibrated against observations from 2014 to 2015 and then applied to explore the potential risk of high atrazine concentrations in the reservoir driven by agriculture activities. Our results show that the model is capable of describing the spatial and temporal patterns of water temperature, salinity and the dynamic distributions of two representative emerging contaminants (i.e. atrazine and BPA) in the reservoir. The physical and biodegradation processes in this study were found to play a crucial role in determining the fate and transport of atrazine and BPA in the reservoir. The model also provides an insight into the potential risk of emerging contaminants and possible mitigation thresholds. The integrated approach can be a very useful tool to support policy-makers in the future management of Qingcaosha Reservoir. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Self-Gated Free-Breathing 3D Coronary CINE Imaging with Simultaneous Water and Fat Visualization

    PubMed Central

    Liu, Jing; Nguyen, Thanh D.; Zhu, Yanchun; Spincemaille, Pascal; Prince, Martin R.; Weinsaft, Jonathan W.; Saloner, David; Wang, Yi

    2014-01-01

    The aim of this study was to develop a novel technique for acquiring 3-dimensional (3D) coronary CINE magnetic resonance images with both water and fat visualization during free breathing and without external respiratory or cardiac gating. The implemented multi-echo hybrid 3D radial balanced Steady-State Free Precession (SSFP) sequence has an efficient data acquisition and is robust against motion. The k-space center along the slice encoding direction was repeatedly acquired to derive both respiratory and cardiac self-gating signals without an increase in scan time, enabling a free-breathing acquisition. The multi-echo acquisition allowed image reconstruction with water-fat separation, providing improved visualization of the coronary artery lumen. Ten healthy subjects were imaged successfully at 1.5 T, achieving a spatial resolution of 1.0×1.0×3.0 mm3 and scan time of about 5 minutes. The proposed imaging technique provided coronary vessel depiction comparable to that obtained with conventional breath-hold imaging and navigator gated free-breathing imaging. PMID:24586682

  1. 3D measurement of the radiation distribution in a water phantom in a hadron therapy beam

    NASA Astrophysics Data System (ADS)

    Opalka, L.; Granja, C.; Hartmann, B.; Jakubek, J.; Jaekel, O.; Martisikova, M.; Pospisil, S.; Solc, J.

    2012-01-01

    Hadron therapy is a highly precise radio-therapeutic method with many advantages especially in cases when the tumour is close to sensitive organs where standard treatments cannot be used. For reliable treatment planning it is necessary to have calculation tools for maximization of the dose delivered to the targeted tissue and minimization of the dose outside of it. While the main physical processes in material irradiated by hadron beams are known, in reality the processes involved are complex so that analytical computations are impossible. Thus, the planning tools to incorporate simplified models and numerical approximations and an experimental method for high precision verification of the models within phantoms is desired. The development of sensitive, high resolution and online methods for measurement of the radiation environment inside of the irradiated object is the aim of this work. Such measurements are made possible by the resolving power of the state-of-the-art pixel detector Timepix. This quantum counting imaging device is able to record the characteristic shapes of the particle traces including their energies deposited in the detector. All these data recorded for each event allow to estimate the particle type, its energy and direction of flight. Event-by-event analysis is done using pattern recognition of the characteristic traces. The objective of the experiment is the detection and characterization of secondary radiation generated by the primary therapeutic beams in tissue equivalent material (water). Measurements were performed inside of a water phantom irradiated by a carbon beam at the Heidelberg Ion-Beam Therapy Center (HIT).

  2. Evaluating the Performance of Unmanned Ground Vehicle Water Detection

    NASA Technical Reports Server (NTRS)

    Rankin, Arturo; Ivanov, Tonislav; Brennan, Shane

    2010-01-01

    Water detection is a critical perception requirement for unmanned ground vehicle (UGV) autonomous navigation over cross-country terrain. During the Robotics Collaborative Technology Alliances (RCTA) program, the Jet Propulsion Laboratory (JPL) developed a set of water detection algorithms that are used to detect, localize, and avoid water bodies large enough to be a hazard to a UGV. The JPL water detection software performs the detection and localization stages using a forward-looking stereo pair of color cameras. The 3D coordinates of water body surface points are then output to a UGV's autonomous mobility system, which is responsible for planning and executing safe paths. There are three primary methods for evaluating the performance of the water detection software. Evaluations can be performed in image space on the intermediate detection product, in map space on the final localized product, or during autonomous navigation to characterize the avoidance of a variety of water bodies. This paper describes a methodology for performing the first two types of water detection performance evaluations.

  3. Evaluating the Performance of Unmanned Ground Vehicle Water Detection

    NASA Technical Reports Server (NTRS)

    Rankin, Arturo; Ivanov, Tonislav; Brennan, Shane

    2010-01-01

    Water detection is a critical perception requirement for unmanned ground vehicle (UGV) autonomous navigation over cross-country terrain. During the Robotics Collaborative Technology Alliances (RCTA) program, the Jet Propulsion Laboratory (JPL) developed a set of water detection algorithms that are used to detect, localize, and avoid water bodies large enough to be a hazard to a UGV. The JPL water detection software performs the detection and localization stages using a forward-looking stereo pair of color cameras. The 3D coordinates of water body surface points are then output to a UGV's autonomous mobility system, which is responsible for planning and executing safe paths. There are three primary methods for evaluating the performance of the water detection software. Evaluations can be performed in image space on the intermediate detection product, in map space on the final localized product, or during autonomous navigation to characterize the avoidance of a variety of water bodies. This paper describes a methodology for performing the first two types of water detection performance evaluations.

  4. Quality of ground water in Idaho

    USGS Publications Warehouse

    Yee, Johnson J.; Souza, William R.

    1987-01-01

    The major aquifers in Idaho are categorized under two rock types, sedimentary and volcanic, and are grouped into six hydrologic basins. Areas with adequate, minimally adequate, or deficient data available for groundwater-quality evaluations are described. Wide variations in chemical concentrations in the water occur within individual aquifers, as well as among the aquifers. The existing data base is not sufficient to describe fully the ground-water quality throughout the State; however, it does indicate that the water is generally suitable for most uses. In some aquifers, concentrations of fluoride, cadmium, and iron in the water exceed the U.S. Environmental Protection Agency's drinking-water standards. Dissolved solids, chloride, and sulfate may cause problems in some local areas. Water-quality data are sparse in many areas, and only general statements can be made regarding the areal distribution of chemical constituents. Few data are available to describe temporal variations of water quality in the aquifers. Primary concerns related to special problem areas in Idaho include (1) protection of water quality in the Rathdrum Prairie aquifer, (2) potential degradation of water quality in the Boise-Nampa area, (3) effects of widespread use of drain wells overlying the eastern Snake River Plain basalt aquifer, and (4) disposal of low-level radioactive wastes at the Idaho National Engineering Laboratory. Shortcomings in the ground-water-quality data base are categorized as (1) multiaquifer sample inadequacy, (2) constituent coverage limitations, (3) baseline-data deficiencies, and (4) data-base nonuniformity.

  5. Ground-water models for water resource planning

    USGS Publications Warehouse

    Moore, J.E.

    1983-01-01

    In the past decade hydrogeologists have emphasized the development of computer-based mathematical models to aid in the understanding of flow, the transport of solutes, transport of heat, and deformation in the ground-water system. These models have been used to provide information and predictions for water managers. Too frequently, ground-water was neglected in water resource planning because managers believed that it could not be adequately evaluated in terms of availability, quality, and effect of development on surface-water supplies. Now, however, with newly developed digital ground-water models, effects of development can be predicted. Such models have been used to predict hydrologic and quality changes under different stresses. These models have grown in complexity over the last ten years from simple one-layer models to three-dimensional simulations of ground-water flow, which may include solute transport, heat transport, effects of land subsidence, and encroachment of saltwater. Case histories illustrate how predictive ground-water models have provided the information needed for the sound planning and management of water resources in the USA. ?? 1983 D. Reidel Publishing Company.

  6. On the transition towards slow manifold in shallow-water and 3D Euler equations in a rotating frame

    NASA Technical Reports Server (NTRS)

    Mahalov, A.

    1994-01-01

    The long-time, asymptotic state of rotating homogeneous shallow-water equations is investigated. Our analysis is based on long-time averaged rotating shallow-water equations describing interactions of large-scale, horizontal, two-dimensional motions with surface inertial-gravity waves field for a shallow, uniformly rotating fluid layer. These equations are obtained in two steps: first by introducing a Poincare/Kelvin linear propagator directly into classical shallow-water equations, then by averaging. The averaged equations describe interaction of wave fields with large-scale motions on time scales long compared to the time scale 1/f(sub o) introduced by rotation (f(sub o)/2-angular velocity of background rotation). The present analysis is similar to the one presented by Waleffe (1991) for 3D Euler equations in a rotating frame. However, since three-wave interactions in rotating shallow-water equations are forbidden, the final equations describing the asymptotic state are simplified considerably. Special emphasis is given to a new conservation law found in the asymptotic state and decoupling of the dynamics of the divergence free part of the velocity field. The possible rising of a decoupled dynamics in the asymptotic state is also investigated for homogeneous turbulence subjected to a background rotation. In our analysis we use long-time expansion, where the velocity field is decomposed into the 'slow manifold' part (the manifold which is unaffected by the linear 'rapid' effects of rotation or the inertial waves) and a formal 3D disturbance. We derive the physical space version of the long-time averaged equations and consider an invariant, basis-free derivation. This formulation can be used to generalize Waleffe's (1991) helical decomposition to viscous inhomogeneous flows (e.g. problems in cylindrical geometry with no-slip boundary conditions on the cylinder surface and homogeneous in the vertical direction).

  7. Ground-water provinces of Brazil

    USGS Publications Warehouse

    Schneider, Robert

    1962-01-01

    As part of a study of the status of investigations and development of ground water in Brazil, made under the auspices of the United States International Cooperation Administration and with the cooperation of the Government of Brazil, the country was divided into seven ground-water provinces. The identification and delineation of the provinces were based on the regional distribution of the dominant geologic units which are known or inferred to have distinctive water-bearing characteristics. Three of the provinces, covering most of the country, are underlain by Precambrian crystalline rocks. Three others coincide in part with four extensive sedimentary basins--the Parnaiba or Maranhfio basin and the contiguous Sao Francisco basin in the northeast and east, the Amazon basin in the north and northwest, and the Paranfi basin in the south and southwest. In addition, the narrow, discontinuous coastal plain is considered as a province. the occurrence of ground water is discussed briefly, and pertinent data are given on the more important aquifers, together with information on some existing wells. Because of the widespread distribution of crystalline rocks of low permeability, it is difficult in many areas to develop large or even adequate ground-water supplies. In general, satisfactory supplies of water are available in most of the rest of the country. Some problems include the relative deficiency of rainfall in the northeast together with the occurrence, in parts of this region, of mineralized water in the crystalline rocks. Also, there is a potential problem of excessive lowering of water levels and interference among wells in the intensively developed area of the city of Sao Paulo.

  8. Well-posedness of linearized motion for 3-D water waves far from equilibrium

    SciTech Connect

    Hou, T.Y.; Zhen-huan Teng; Pingwen Zhang

    1996-12-31

    In this paper, we study the motion of a free surface separating two different layers of fluid in three dimensions. We assume the flow to be inviscid, irrotational, and incompressible. In this case, one can reduce the entire motion by variables on the surface alone. In general, without additional regularizing effects such as surface alone. In general, without additional regularizing effects such as surface tension or viscosity, the flow can be subject to Rayleigh-Taylor or Kelvin-Helmholtz instabilities which will lead to unbounded growth in high frequency wave numbers. In this case, the problem is not well-posed in the Hadamard sense. The problem of water wave with no fluid above is a special case. It is well-known that such motion is well-posed when the free surface is sufficiently close to equilibrium. Beale, Hous and Lowengrub derived a general condition which ensures well-posedness of the linearization about a presumed time-dependent motion in two dimensional case. The linearized equations, when formulated in a proper coordinate system are found to have a qualitative structure surprisingly like that for the simple case of linear waves near equilbrium. Such an analysis is essential in analyzing stability of boundary integral methods for computing free interface problems. 19 refs.

  9. Integrating Sensors into a Marine Drone for Bathymetric 3D Surveys in Shallow Waters

    PubMed Central

    Giordano, Francesco; Mattei, Gaia; Parente, Claudio; Peluso, Francesco; Santamaria, Raffaele

    2015-01-01

    This paper demonstrates that accurate data concerning bathymetry as well as environmental conditions in shallow waters can be acquired using sensors that are integrated into the same marine vehicle. An open prototype of an unmanned surface vessel (USV) named MicroVeGA is described. The focus is on the main instruments installed on-board: a differential Global Position System (GPS) system and single beam echo sounder; inertial platform for attitude control; ultrasound obstacle-detection system with temperature control system; emerged and submerged video acquisition system. The results of two cases study are presented, both concerning areas (Sorrento Marina Grande and Marechiaro Harbour, both in the Gulf of Naples) characterized by a coastal physiography that impedes the execution of a bathymetric survey with traditional boats. In addition, those areas are critical because of the presence of submerged archaeological remains that produce rapid changes in depth values. The experiments confirm that the integration of the sensors improves the instruments’ performance and survey accuracy. PMID:26729117

  10. Integrating Sensors into a Marine Drone for Bathymetric 3D Surveys in Shallow Waters.

    PubMed

    Giordano, Francesco; Mattei, Gaia; Parente, Claudio; Peluso, Francesco; Santamaria, Raffaele

    2015-12-29

    This paper demonstrates that accurate data concerning bathymetry as well as environmental conditions in shallow waters can be acquired using sensors that are integrated into the same marine vehicle. An open prototype of an unmanned surface vessel (USV) named MicroVeGA is described. The focus is on the main instruments installed on-board: a differential Global Position System (GPS) system and single beam echo sounder; inertial platform for attitude control; ultrasound obstacle-detection system with temperature control system; emerged and submerged video acquisition system. The results of two cases study are presented, both concerning areas (Sorrento Marina Grande and Marechiaro Harbour, both in the Gulf of Naples) characterized by a coastal physiography that impedes the execution of a bathymetric survey with traditional boats. In addition, those areas are critical because of the presence of submerged archaeological remains that produce rapid changes in depth values. The experiments confirm that the integration of the sensors improves the instruments' performance and survey accuracy.

  11. NITRATE CONTAMINATION OF GROUND WATER (GW-761)

    EPA Science Inventory

    The occurrence of nitrate and related compounds in ground water is discussed from the perspectives of its natural as well as anthropogenic origins. A brief explanation of the nitrogen cycle touches on the production as well as utilization of ammonia, nitrite, nitrate, and nitrog...

  12. PRIORITIZATION OF GROUND WATER CONTAMINANTS AND SOURCES

    EPA Science Inventory

    The objective of this research was to identify chemical, physical, bacteriological, and viral contaminants, and their sources, which present the greatest health threat in public ground water supplies in the USA; and to classify (prioritize) such contaminants and relative to their...

  13. Selenium in Oklahoma ground water and soil

    SciTech Connect

    Atalay, A.; Vir Maggon, D.

    1991-03-30

    Selenium with a consumption of 2 liters per day (5). The objectives of this study are: (1) to determine the concentrations of Se in Oklahoma ground water and soil samples. (2) to map the geographical distribution of Se species in Oklahoma. (3) to relate groundwater depth, pH and geology with concentration of Se.

  14. Ground water work breakdown structure dictionary

    SciTech Connect

    1995-04-01

    This report contains the activities that are necessary to assess in ground water remediation as specified in the UMTRA Project. These activities include the following: site characterization; remedial action compliance and design documentation; environment, health, and safety program; technology assessment; property access and acquisition activities; site remedial actions; long term surveillance and licensing; and technical and management support.

  15. Trace metal concentrations in shallow ground water

    USGS Publications Warehouse

    Zelewski, L.M.; Krabbenhoft, D.P.; Armstrong, D.E.

    2001-01-01

    Trace metal clean sampling and analysis techniques were used to examine the temporal patterns or Hg, Cu, and Zn concentrations in shallow ground water, and the relationships between metal concentrations in ground water and in a hydrologically connected river. Hg, Cu, and Zn concentrations in ground water ranged from 0.07 to 4.6 ng L-1, 0.07 to 3.10 ??g L-1, and 0.17 to 2.18 ??g L-1, respectively. There was no apparent seasonal pattern in any of the metal concentrations. Filtrable Hg, Cu, and Zn concentrations in the North Branch of the Milwaukee River ranged from below the detection limit to 2.65 ng Hg L-1, 0.51 to 4.30 ??g Cu L-1, and 0.34 to 2.33 ??g Zn L-1. Thus, metal concentrations in ground water were sufficiently high to account for a substantial fraction of the filtrable trace metal concentration in the river. Metal concentrations in the soil ranged from 8 to 86 ng Hg g-1, 10 to 39 ??g Cu g-1, and 15 to 84 ??g Zn g-1. Distribution coefficients, KD, in the aquifer were 7900, 22,000, and 23,000 L kg-1 for Hg, Cu, and Zn, respectively. These values were three to 40 times smaller than KD values observed in the Milwaukee River for suspended particulate matter.

  16. EPA'S GROUND WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    The purpose and the services provided by EPA's Ground Water Technical Support Center (GWTSC) will be presented. In 1987 the Office of Solid Waste and Emergency Response, Regional Waste Management Offices, and ORD established the Technical Support Project (TSP)

    The purpos...

  17. Ground Water in a Fish Tank.

    ERIC Educational Resources Information Center

    Mayshark, Robin K.

    1992-01-01

    Describes creating a Model Aquatic/Terrestrial Ecosystem for use in helping students understand how water moves beneath the ground's surface. The model is constructed from a fish tank using rocks, soil, gravel, clay, and organic materials. Author describes possible cooperative-learning and problem-solving activities that can be done with this…

  18. Ground Water Sampling for Metal Analyses

    EPA Pesticide Factsheets

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Superfund cleanup ractices occurs where one EPA Region implements a remedial action based on...

  19. PRIORITIZATION OF GROUND WATER CONTAMINANTS AND SOURCES

    EPA Science Inventory

    The objective of this research was to identify chemical, physical, bacteriological, and viral contaminants, and their sources, which present the greatest health threat in public ground water supplies in the USA; and to classify (prioritize) such contaminants and relative to their...

  20. IN-SITU BIOREMEDIATION OF GROUND WATER

    EPA Science Inventory

    The Robert S. Kerr Environmental Research Laboratory (RSKERL) has developed a number of Issue Papers and Briefing Documents which are designed to exchange up-to-date information related to the remediation of contaminated soil and ground water at hazardous waste sites. n an attemp...

  1. IN-SITU BIOREMEDIATION OF GROUND WATER

    EPA Science Inventory

    The Robert S. Kerr Environmental Research Laboratory (RSKERL) has developed a number of Issue Papers and Briefing Documents which are designed to exchange up-to-date information related to the remediation of contaminated soil and ground water at hazardous waste sites. n an attemp...

  2. EPA'S GROUND WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    The purpose and the services provided by EPA's Ground Water Technical Support Center (GWTSC) will be presented. In 1987 the Office of Solid Waste and Emergency Response, Regional Waste Management Offices, and ORD established the Technical Support Project (TSP)

    The purpos...

  3. Ground Water in a Fish Tank.

    ERIC Educational Resources Information Center

    Mayshark, Robin K.

    1992-01-01

    Describes creating a Model Aquatic/Terrestrial Ecosystem for use in helping students understand how water moves beneath the ground's surface. The model is constructed from a fish tank using rocks, soil, gravel, clay, and organic materials. Author describes possible cooperative-learning and problem-solving activities that can be done with this…

  4. Areas contributing ground water to the Peconic Estuary, and ground-water budgets for the north and south forks and Shelter Island, eastern Suffolk County, New York

    USGS Publications Warehouse

    Schubert, C.E.

    1998-01-01

    The Peconic Estuary, at the eastern end of Long Island, has been plagued by a recurrent algal bloom, locally referred to as ?Brown Tide,? that has caused the severe decline of local marine resources. Although the factors that trigger Brown Tide blooms remain uncertain, groundwater discharge has previously been shown to affect surface-water quality in the western part of the estuary. A U.S. Geological Survey groundwater- flow model of the main body of Long Island indicates that a total of about 7.5 x 106 ft3/d (cubic feet per day) of freshwater discharges to the western part of the estuary, but the model does not include the ground-water flow systems on the North and South Forks and Shelter Island, which contribute significant amounts of freshwater to the central and eastern parts of the estuary. The need for information on freshwater discharge to the entire estuary prompted the U.S. Geological Survey to evaluate ground-water discharge from the North and South Forks and Shelter Island. Source areas that contribute ground water to the Peconic Estuary were delineated, and groundwater budgets for these areas were developed, to evaluate the distribution and magnitude of ground-water discharge to the central and eastern parts of the estuary. Contributing-area boundaries that were delineated coincide with the hydraulic boundaries of the fresh ground-water-flow systems of the North and South Forks and Shelter Island; these boundaries are of two types? external (saltwater bodies) and internal (groundwater divides). Hydrologic components that were evaluated include recharge from precipitation, public-supply withdrawal and return flow, and agricultural withdrawal. Values for each of these components were calculated or estimated for the individual freshwater flow subsystems that form each ground-water-budget area, then summed to obtain the total discharge of fresh ground water to tidewater. Ground-water discharge to the Peconic Estuary is about 3.8 x 106 ft3/d from the North

  5. Imaging a 3D geological structure from HEM, airborne magnetic and ground ERT data in Kalat-e-Reshm area, Iran

    NASA Astrophysics Data System (ADS)

    Shirzaditabar, Farzad; Bastani, Mehrdad; Oskooi, Behrooz

    2011-11-01

    A set of geophysical data collected in an area in Iran are analyzed to check the validity of a geological map that was prepared in connection to a mineral prospecting project and also to image the spatial electrical resistivity distribution. The data set includes helicopter electromagnetic (HEM), airborne magnetic and ground electrical resistivity measurement. Occam approach was used to invert the HEM data to model the resistivity using a layered earth model with fixed thicknesses. The algorithm is based on a nonlinear inverse problem in a least-squares sense. The algorithm was tested on a part of an HEM dataset acquired with a DIGHEM helicopter EM system at Kalat-e-Reshm, Semnan in Iran. The area contains a resistive porphyry andesite that is covered by Eocene sedimentary units. The results are shown as resistivity sections and maps confirming the existence of an arc like resistive structure in the survey area. The resistive andesite seems to be thicker than it is indicated in the geological maps. The results are compared with the reduced to the pole (RTP) airborne magnetic anomaly field data as well as with two ground resistivity profiles. We found reasonable correlations between the HEM 1D resistivity models and 2D models from electrical resistivity tomography (ERT) inversions. A 3D visualization of the 1D models along all flight lines provided a useful tool for the study of spatial variations of the resistivity structure in the investigation area.

  6. Identifying the origin of differences between 3D numerical simulations of ground motion in sedimentary basins: lessons from stringent canonical test models in the E2VP framework

    NASA Astrophysics Data System (ADS)

    Chaljub, Emmanuel; Maufroy, Emeline; Moczo, Peter; Kristek, Jozef; Priolo, Enrico; Klin, Peter; De Martin, Florent; Zhang, Zenghuo; Hollender, Fabrice; Bard, Pierre-Yves

    2013-04-01

    Numerical simulation is playing a role of increasing importance in the field of seismic hazard by providing quantitative estimates of earthquake ground motion, its variability, and its sensitivity to geometrical and mechanical properties of the medium. Continuous efforts to develop accurate and computationally efficient numerical methods, combined with increasing computational power have made it technically feasible to calculate seismograms in 3D realistic configurations and for frequencies of interest in seismic design applications. Now, in order to foster the use of numerical simulations in practical prediction of earthquake ground motion, it is important to evaluate the accuracy of current numerical methods when applied to realistic 3D sites. This process of verification is a necessary prerequisite to confrontation of numerical predictions and observations. Through the ongoing Euroseistest Verification and Validation Project (E2VP), which focuses on the Mygdonian basin (northern Greece), we investigated the capability of numerical methods to predict earthquake ground motion for frequencies up to 4 Hz. Numerical predictions obtained by several teams using a wide variety of methods were compared using quantitative goodness-of-fit criteria. In order to better understand the cause of misfits between different simulations, initially performed for the realistic geometry of the Mygdonian basin, we defined five stringent canonical configurations. The canonical models allow for identifying sources of misfits and quantify their importance. Detailed quantitative comparison of simulations in relation to dominant features of the models shows that even relatively simple heterogeneous models must be treated with maximum care in order to achieve sufficient level of accuracy. One important conclusion is that the numerical representation of models with strong variations (e.g. discontinuities) may considerably vary from one method to the other, and may become a dominant source of

  7. Ground water and the rural homeowner

    USGS Publications Warehouse

    Waller, Roger M.

    1988-01-01

    As the salesmen sang in the musical The Music Man, "You gotta know the territory." This saying is also true when planning to buy or build a house. Learn as much as possible about the land, the water supply, and the septic system of the house before buying or building. Do not just look at the construction aspects or the beauty of the home and surroundings. Be sure to consider the environmental conditions around and beneath the site as well. Try to visit the site under adverse conditions, such as during heavy rain or meltwater runoff, to observe the drainage characteristics, particularly the condition of the basement. Many of the conditions discussed in this book, such as lowered well-water levels, flooded basements, and contamination from septic systems, are so common that rural families often have to deal with one or more of them. The purpose of this book is to awaken an interest in ground water and an awareness of where it is available, how it moves, how people can adjust to its patterns to avoid problems, and how it can be protected and used wisely. This booklet provides both present and prospective rural homeowners, particularly those in the glaciated northern parts of the United States, with a basic but comprehensive description of ground water. It also presents problems one may expect to encounter with ground water and some solutions or suggestions for help with these problems.

  8. Ground water and the rural homeowner

    USGS Publications Warehouse

    Waller, Roger M.

    1994-01-01

    As the salesmen sang in the musical The Music Man, "You gotta know the territory." This saying is also true when planning to buy or build a house. Learn as much as possible about the land, the water supply, and the septic system of the house before buying or building. Do not just look at the construction aspects or the beauty of the home and surroundings. Be sure to consider the environmental conditions around and beneath the site as well. Try to visit the site under adverse conditions, such as during heavy rain or meltwater runoff, to observe the drainage characteristics, particularly the condition of the basement. Many of the conditions discussed in this book, such as lowered well-water levels, flooded basements, and contamination from septic systems, are so common that rural families often have to deal with one or more of them. The purpose of this book is to awaken an interest in ground water and an awareness of where it is available, how it moves, how people can adjust to its patterns to avoid problems, and how it can be protected and used wisely. This booklet provides both present and prospective rural homeowners, particularly those in the glaciated northern parts of the United States, with a basic but comprehensive description of ground water. It also presents problems one may expect to encounter with ground water and some solutions or suggestions for help with these problems.

  9. Reading Ground Water Levels with a Smartphone

    NASA Astrophysics Data System (ADS)

    van Overloop, Peter-Jules

    2015-04-01

    Most ground water levels in the world are measured manually. It requires employees of water management organizations to visit sites in the field and execute a measurement procedure that requires special tools and training. Once the measurement is done, the value is jotted down in a notebook and later, at the office, entered in a computer system. This procedure is slow and prone to human errors. A new development is the introduction of modern Information and Communication Technology to support this task and make it more efficient. Two innovations are introduced to measure and immediately store ground water levels. The first method is a measuring tape that gives a sound and light when it just touches the water in combination with an app on a smartphone with which a picture needs to be taken from the measuring tape. Using dedicated pattern recognition algorithms, the depth is read on the tape and it is verified if the light is on. The second method estimates the depth using a sound from the smartphone that is sent into the borehole and records the reflecting waves in the pipe. Both methods use gps-localization of the smartphone to store the depths in the right location in the central database, making the monitoring of ground water levels a real-time process that eliminates human errors.

  10. Toward 3D graphene oxide gels based adsorbents for high-efficient water treatment via the promotion of biopolymers.

    PubMed

    Cheng, Chong Sage; Deng, Jie; Lei, Bei; He, Ai; Zhang, Xiang; Ma, Lang; Li, Shuang; Zhao, Changsheng

    2013-12-15

    Recent studies showed that graphene oxide (GO) presented high adsorption capacities to various water contaminants. However, the needed centrifugation after adsorption and the potential biological toxicity of GO restricted its applications in wastewater treatment. In this study, a facile method is provided by using biopolymers to mediate and synthesize 3D GO based gels. The obtained hybrid gels present well-defined and interconnected 3D porous network, which allows the adsorbate molecules to diffuse easily into the adsorbent. The adsorption experiments indicate that the obtained porous GO-biopolymer gels can efficiently remove cationic dyes and heavy metal ions from wastewater. Methylene blue (MB) and methyl violet (MV), two cationic dyes, are chosen as model adsorbates to investigate the adsorption capability and desorption ratio; meanwhile, the influence of contacting time, initial concentration, and pH value on the adsorption capacity of the prepared GO-biopolymer gels are also studied. The GO-biopolymer gels displayed an adsorption capacity as high as 1100 mg/g for MB dye and 1350 mg/g for MV dye, respectively. Furthermore, the adsorption kinetics and isotherms of the MB were studied in details. The experimental data of MB adsorption fitted well with the pseudo-second-order kinetic model and the Langmuir isotherm, and the results indicated that the adsorption process was controlled by the intraparticle diffusion. Moreover, the adsorption data revealed that the porous GO-biopolymer gels showed good selective adsorbability to cationic dyes and metal ions.

  11. Simulation of ground-water flow and areas contributing ground water to production wells, Cadillac, Michigan

    USGS Publications Warehouse

    Hoard, Christopher J.; Westjohn, David B.

    2005-01-01

    Ground water is the primary source of water for domestic, municipal, and industrial use within the northwest section of Michigan's Lower Peninsula. Because of the importance of this resource, numerous communities including the city of Cadillac in Wexford County, Michigan, have begun local wellhead protection programs. In these programs, communities protect their ground-water resources by identifying the areas that contribute water to production wells, identifying potential sources of contamination, and developing methods to cooperatively manage and minimize threats to the water supply. The U.S. Geological Survey, in cooperation with the city of Cadillac, simulated regional ground-water flow and estimated areas contributing recharge and zones of transport to the production well field. Ground-water flow models for the Clam River watershed, in Wexford and Missaukee Counties, were developed using the U.S. Geological Survey modular three-dimensional finite-difference ground-water flow model (MODFLOW 2000). Ground-water flow models were calibrated using the observation, sensitivity, and parameter estimation packages of MODFLOW 2000. Ground-water-head solutions from calibrated flow models were used in conjunction with MODPATH, a particle-tracking program, to simulate regional ground-water flow and estimate areas contributing recharge and zones of transport to the Cadillac production-well field for a 10-year period. Model simulations match the conceptual model in that regional ground-water flow in the deep ground-water system is from southeast to northwest across the watershed. Areas contributing water were determined for the optimized parameter set and an alternate parameter set that included increased recharge and hydraulic conductivity values. Although substantially different hydrologic parameters (assumed to represent end-member ranges of realistic hydrologic parameters) were used in alternate numerical simulations, simulation results differ little in predictions of

  12. Ground-water data for Michigan, 1977

    USGS Publications Warehouse

    Huffman, G.C.

    1979-01-01

    The purpose of this report is to make available the 1977 records of water levels and related data for the principal aquifers of the State. These records and data provide a means for evaluating available ground-water supplies. Long- term records serve as a framework to which short-term records may be related. Also, water levels in areas of heavy pumping may be compared to levels in areas of little or no pumping. This report is written for municipalities, industries, institutions, consultants, drillers, hydrologists, and other people interested in the groundwater resources of the State.

  13. ERTS imagery for ground-water investigations

    USGS Publications Warehouse

    Moore, Gerald K.; Deutsch, Morris

    1975-01-01

    ERTS imagery offers the first opportunity to apply moderately high-resolution satellite data to the nationwide study of water resources. This imagery is both a tool and a form of basic data. Like other tools and basic data, it should be considered for use in ground-water investigations. The main advantage of its use will be to reduce the need for field work. In addition, however, broad regional features may be seen easily on ERTS imagery, whereas they would be difficult or impossible to see on the ground or on low-altitude aerial photographs. Some present and potential uses of ERTS imagery are to locate new aquifers, to study aquifer recharge and discharge, to estimate ground-water pumpage for irrigation, to predict the location and type of aquifer management problems, and to locate and monitor strip mines which commonly are sources for acid mine drainage. In many cases, boundaries which are gradational on the ground appear to be sharp on ERTS imagery. Initial results indicate that the accuracy of maps produced from ERTS imagery is completely adequate for some purposes.

  14. Ground-water reconnaissance of American Samoa

    USGS Publications Warehouse

    Davis, Daniel Arthur

    1963-01-01

    The principal islands of American Samoa are Tutuila, Aunuu, Ofu, Olosega, and Ta'u, which have a total area of about 72 square miles and a population of about 20,000. The mean annual rainfall is 150 to 200 inches. The islands are volcanic in origin and are composed of lava flows, dikes, tuff. and breccia, and minor amounts of talus, alluvium, and calcareous sand and gravel. Tutuila is a complex island formed of rocks erupted from five volcanoes. Aunuu is a tuff cone. Ofu, Olosega, and Ta'u are composed largely of thin-bedded lava flows. Much of the rock of Tutuila has low permeability, and most of the ground water is in high-level reservoirs that discharge at numerous small springs and seeps. The flow from a few springs and seeps is collected in short tunnels or in basins for village supply, but most villages obtain their water from streams. A large supply of basal ground water may underlie the Tafuna-Leone plain at about sea level in permeable lava flows. Small basal supplies may be in alluvial fill at the mouths of large valleys. Aunuu has small quantities of basal water in beach deposits of calcareous sand and gravel. Minor amounts of high-level ground-water flow from springs and seeps on Ofu, Olosega, and Ta'u. The generally permeable lava flows in the three islands contain substantial amounts of basal ground water that can be developed in coastal areas in wells dug to about sea level.

  15. Identifying well contamination through the use of 3-D fluorescence spectroscopy to classify coalbed methane produced water.

    PubMed

    Dahm, Katharine G; Van Straaten, Colette M; Munakata-Marr, Junko; Drewes, Jörg E

    2013-01-02

    Production of unconventional gas resources commonly requires the use of hydraulic fracturing and chemical production well additives. Concern exists for the use of chemical compounds in gas wells due to the risk of groundwater contamination. This study focuses on a proposed method of identifying groundwater contamination from gas production. The method focuses on the classification of naturally occurring organic signatures of coalbed methane (CBM) produced water compared to anthropogenic organic compounds. The 3-D fluorescence excitation-emission matrix (EEM) spectra of coalbed methane produced water samples revealed four peaks characteristic of coalbed methane produced water: Peak P (aromatic proteins region), Peak M(1) (microbial byproducts region), Peak M(2) (microbial byproducts region), and Peak H (humic acid-like region). Peak H is characteristic of the coal-water equilibria present in all basins, while peaks P and M(2) correlate with microbial activity in basins with biogenic methane generation pathways. Anthropogenic well additives produce EEM signatures with notable flooding of peaks P, M(1), M(2), and H, relatively higher overall fluorescence intensity, and slightly higher DOC concentrations. Fluorescence spectroscopy has the potential to be used in conjunction with groundwater contamination studies to determine if detected organic compounds originate from naturally occurring sources or well production additives.

  16. Characterization of Climax granite ground water

    SciTech Connect

    Isherwood, D.; Harrar, J.; Raber, E.

    1982-08-01

    The Climax ground water fails to match the commonly held views regarding the nature of deep granitic ground waters. It is neither dilute nor in equilibrium with the granite. Ground-water samples were taken for chemical analysis from five sites in the fractured Climax granite at the Nevada Test Site. The waters are high in total dissolved solids (1200 to 2160 mg/L) and rich in sodium (56 to 250 mg/L), calcium (114 to 283 mg/L) and sulfate (325 to 1060 mg/L). Two of the samples contained relatively high amounts of uranium (1.8 and 18.5 mg/L), whereas the other three contained uranium below the level of detection (< 0.1 mg/L). The pH is in the neutral range (7.3 to 8.2). The differences in composition between samples (as seen in the wide range of values for the major constituents and total dissolved solids) suggest the samples came from different, independent fracture systems. However, the apparent trend of increasing sodium with depth at the expense of calcium and magnesium suggests a common evolutionary chemical process, if not an interconnected system. The waters appear to be less oxidizing with depth (+ 410 mV at 420 m below the surface vs + 86 mV at 565 m). However, with Eh measurements on only two samples, this correlation is questionable. Isotopic analyses show that the waters are of meteoric origin and that the source of the sulfate is probably the pyrite in the fracture-fill material. Analysis of the measured water characteristics using the chemical equilibrium computer program EQ3 indicates that the waters are not in equilibrium with the local mineral assemblage. The solutions appear to be supersaturated with respect to the mineral calcite, quartz, kaolinite, muscovite, k-feldspar, and many others.

  17. Ground water exfiltration in a river oxbow

    NASA Astrophysics Data System (ADS)

    Suck, M.; Nützmann, G.; Lewandowski, J.

    2009-04-01

    This paper deals with the quantification of the exchange between ground water and surface water in a river oxbow. Implementation and evaluation of the study site are based upon a conceptual model, in which exfiltration into the oxbow and mainly into the adjacent river Spree are supposed as major transport processes. A clogging mud layer in the oxbow with its low hydraulic conductivity controls exfiltration and is the highest hydraulic resistance in the considered aquatic system. The measurement of temperature depth profiles within that layer was one of the methods applied to measure groundwater exfiltration. Because of the different groundwater and surface water temperatures there are temperature differences between the upper and lower boundary of the mud layer. Depending on the extent of ground water exfiltration that depth profile is more or less curved. By adaptation of an analytical solution to the plotted temperature depth profiles the flux rates were calculated. A supplementary method to measure exfiltration, the seepage meter, is used for direct measurements of the flux rates. With that method the ground water flux which passes a defined cross section of the sediment-water boundary is collected. The evaluation of the results yields higher exfiltration rates for the temperature depth profiles than for the seepage meters. For the seepage meters the results show only a part of the actual flux rates because of several error sources. Despite those errors the comparison of the results from both methods shows a similar flux pattern with strong small-scale heterogeneities. At scales of few meters the measured flux rates fluctuate more than an order of magnitude. The flux rates near the bank are frequently higher than in the middle of the oxbow. However, the flux rates are controlled by the thickness of the clogging mud layer, its hydraulic conductivity, its heterogeneity and the water table differences between surface water and adjacent aquifer.

  18. Numerical model of water flow and solute accumulation in vertisols using HYDRUS 2D/3D code

    NASA Astrophysics Data System (ADS)

    Weiss, Tomáš; Dahan, Ofer; Turkeltub, Tuvia

    2015-04-01

    Keywords: dessication-crack-induced-salinization, preferential flow, conceptual model, numerical model, vadose zone, vertisols, soil water retention function, HYDRUS 2D/3D Vertisols cover a hydrologically very significant area of semi-arid regions often through which water infiltrates to groundwater aquifers. Understanding of water flow and solute accumulation is thus very relevant to agricultural activity and water resources management. Previous works suggest a conceptual model of dessication-crack-induced-salinization where salinization of sediment in the deep section of the vadose zone (up to 4 m) is induced by subsurface evaporation due to convective air flow in the dessication cracks. It suggests that the salinization is induced by the hydraulic gradient between the dry sediment in the vicinity of cracks (low potential) and the relatively wet sediment further from the main cracks (high potential). This paper presents a modified previously suggested conceptual model and a numerical model. The model uses a simple uniform flow approach but unconventionally prescribes the boundary conditions and the hydraulic parameters of soil. The numerical model is bound to one location close to a dairy farm waste lagoon, but the application of the suggested conceptual model could be possibly extended to all semi-arid regions with vertisols. Simulations were conducted using several modeling approaches with an ultimate goal of fitting the simulation results to the controlling variables measured in the field: temporal variation in water content across thick layer of unsaturated clay sediment (>10 m), sediment salinity and salinity the water draining down the vadose zone to the water table. The development of the model was engineered in several steps; all computed as forward solutions by try-and-error approach. The model suggests very deep instant infiltration of fresh water up to 12 m, which is also supported by the field data. The paper suggests prescribing a special atmospheric

  19. Encapsulated discrete octameric water cluster, 1D water tape, and 3D water aggregate network in diverse MOFs based on bisimidazolium ligands

    NASA Astrophysics Data System (ADS)

    Shi, Ruo-Bing; Pi, Min; Jiang, Shuang-Shuang; Wang, Yuan-Yuan; Jin, Chuan-Ming

    2014-08-01

    Four new metal-organic frameworks, [Zn(2-mBIM)2(SO3CF3)2·(H2O)4] (1), [Zn(BMIE)(1,4-BDC)]·(H2O)3 (2), [Cd(BIM)2(OH)(H2O)2(PF6)]·(H2O)4 (3), and [Cd(PA-BIM)2 (ClO4)2]·11.33H2O (4) (2-mBIM = bis(2-methylimidazol-1-yl)methane, BMIE = 1,2-bis[1-(2-methylimidazole)-diethoxy]ethane, BIM = bis(imidazol-1-yl)methane, and PA-BIM = 1,1-bis [(2-phenylazo)imidazol-1-yl]methane) have been prepared and structurally characterized. Complex 1 exhibits an infinite 1D cationic beaded-chain structure, which encapsulated discrete octameric water clusters that are comprised of a chair-like hexameric water cluster with two extra water molecules dangling on two diagonal vertices of the chair. Complex 2 forms a 1D infinite zigzag metal-organic chain structure with a 1D T4(0)A(4) water tape. Complexes 3 show a 2D grid-like sheet structure with the 1D water tape T4(0)A(0)2(0) motif. Complex 4 is a porous 3D MOF with tetrahedron-coordinated Cd(II) centers and trans-conformation PA-BIM ligands. These holes are occupied by a fascinating three-dimensional water clathrate network, which consists of cage-shaped structural tetradecameric water cluster (H2O)14 units and six independent bridged water molecules. The results suggest that the bisimidazolium ligands and anions play crucial roles in the formation of the different host structures and different guest water aggregations. Additionally, the thermal stabilities and photoluminescence spectra of the complexes have been discussed.

  20. Validation Analysis for the Calculation of a Turbulent Free Jet in Water Using CFDS-FLOW 3-D and FLUENT

    SciTech Connect

    Dimenna, R.A.; Lee, S.Y.

    1995-05-01

    The application of computational fluid dynamics methods to the analysis of mixing in the high level waste tanks at the Savannah River Site requires a demonstration that the computer codes can properly represent the behavior of fluids in the tanks. The motive force for mixing the tanks is a set of jet pumps taking suction from the tank fluid and discharging turbulent jets near the bottom of the tank. The work described here focuses on the free turbulent jet in water as the simplest case of jet behavior for which data could be found in the open literature. Calculations performed with both CFDS-FLOW3D and FLUENT were compared with data as well as classical jet theory. Results showed both codes agreed reasonably well with each other and with the data, but that results were sensitive to the computational mesh and, to a lesser degree, the selection of turbulence models.

  1. Ground water currents: Developments in innovative ground water treatment, issue No. 13, September 1995

    SciTech Connect

    1995-09-01

    ;Contents: Ground Water Remediation Center; A solution to bioremediation`s soil plugging; Bioremediation video; VISITT 4.0 update; Update on ZENON pervaporation; and Site search-NAPL contaminated site wanted.

  2. SUPERFUND GROUND WATER ISSUE - ACCURACY OF DEPTH TO WATER MEASUREMENTS

    EPA Science Inventory

    Accuracy of depth to water measurements is an issue identified by the Forum as a concern of Superfund decision-makers as they attempt to determine directions of ground-water flow, areas of recharge of discharge, the hydraulic characteristics of aquifers, or the effects of manmade...

  3. SUPERFUND GROUND WATER ISSUE - ACCURACY OF DEPTH TO WATER MEASUREMENTS

    EPA Science Inventory

    Accuracy of depth to water measurements is an issue identified by the Forum as a concern of Superfund decision-makers as they attempt to determine directions of ground-water flow, areas of recharge of discharge, the hydraulic characteristics of aquifers, or the effects of manmade...

  4. Regional 3-D ionospheric electron density specification on the basis of data assimilation of ground-based GNSS and radio occultation data

    NASA Astrophysics Data System (ADS)

    Aa, Ercha; Liu, Siqing; Huang, Wengeng; Shi, Liqin; Gong, Jiancun; Chen, Yanhong; Shen, Hua; Li, Jianyong

    2016-06-01

    In this paper, a regional 3-D ionospheric electron density specification over China and adjacent areas (70°E-140°E in longitude, 15°N-55°N in latitude, and 100-900 km in altitude) is developed on the basis of data assimilation technique. The International Reference Ionosphere (IRI) is used as a background model, and a three-dimensional variational technique is used to assimilate both the ground-based Global Navigation Satellite System (GNSS) observations from the Crustal Movement Observation Network of China (CMONOC) and International GNSS Service (IGS) and the ionospheric radio occultation (RO) data from FORMOSAT-3/COSMIC (F3/C) satellites. The regional 3-D gridded ionospheric electron densities can be generated with temporal resolution of 5 min in universal time, horizontal resolution of 2° × 2° in latitude and longitude, and vertical resolution of 20 km between 100 and 500 km and 50 km between 500 and 900 km. The data assimilation results are validated through extensive comparison with several sources of electron density information, including (1) ionospheric total electron content (TEC); (2) Abel-retrieved F3/C electron density profiles (EDPs); (3) ionosonde foF2 and bottomside EDPs; and (4) the Utah State University Global Assimilation of Ionospheric Measurements (USU-GAIM) under both geomagnetic quiet and disturbed conditions. The validation results show that the data assimilation procedure pushes the climatological IRI model toward the observation, and a general accuracy improvement of 15-30% can be expected. Thecomparisons also indicate that the data assimilation results are more close to the Center for Orbit Determination of Europe (CODE) TEC and Madrigal TEC products than USU-GAIM. These initial results might demonstrate the effectiveness of the data assimilation technique in improving specification of local ionospheric morphology.

  5. Estimating 3D L5/S1 moments and ground reaction forces during trunk bending using a full-body ambulatory inertial motion capture system.

    PubMed

    Faber, G S; Chang, C C; Kingma, I; Dennerlein, J T; van Dieën, J H

    2016-04-11

    Inertial motion capture (IMC) systems have become increasingly popular for ambulatory movement analysis. However, few studies have attempted to use these measurement techniques to estimate kinetic variables, such as joint moments and ground reaction forces (GRFs). Therefore, we investigated the performance of a full-body ambulatory IMC system in estimating 3D L5/S1 moments and GRFs during symmetric, asymmetric and fast trunk bending, performed by nine male participants. Using an ambulatory IMC system (Xsens/MVN), L5/S1 moments were estimated based on the upper-body segment kinematics using a top-down inverse dynamics analysis, and GRFs were estimated based on full-body segment accelerations. As a reference, a laboratory measurement system was utilized: GRFs were measured with Kistler force plates (FPs), and L5/S1 moments were calculated using a bottom-up inverse dynamics model based on FP data and lower-body kinematics measured with an optical motion capture system (OMC). Correspondence between the OMC+FP and IMC systems was quantified by calculating root-mean-square errors (RMSerrors) of moment/force time series and the interclass correlation (ICC) of the absolute peak moments/forces. Averaged over subjects, L5/S1 moment RMSerrors remained below 10Nm (about 5% of the peak extension moment) and 3D GRF RMSerrors remained below 20N (about 2% of the peak vertical force). ICCs were high for the peak L5/S1 extension moment (0.971) and vertical GRF (0.998). Due to lower amplitudes, smaller ICCs were found for the peak asymmetric L5/S1 moments (0.690-0.781) and horizontal GRFs (0.559-0.948). In conclusion, close correspondence was found between the ambulatory IMC-based and laboratory-based estimates of back load. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Estimation of water saturated permeability of soils, using 3D soil tomographic images and pore-level transport phenomena modelling

    NASA Astrophysics Data System (ADS)

    Lamorski, Krzysztof; Sławiński, Cezary; Barna, Gyöngyi

    2014-05-01

    There are some important macroscopic properties of the soil porous media such as: saturated permeability and water retention characteristics. These soil characteristics are very important as they determine soil transport processes and are commonly used as a parameters of general models of soil transport processes used extensively for scientific developments and engineering practise. These characteristics are usually measured or estimated using some statistical or phenomenological modelling, i.e. pedotransfer functions. On the physical basis, saturated soil permeability arises from physical transport processes occurring at the pore level. Current progress in modelling techniques, computational methods and X-ray micro-tomographic technology gives opportunity to use direct methods of physical modelling for pore level transport processes. Physically valid description of transport processes at micro-scale based on Navier-Stokes type modelling approach gives chance to recover macroscopic porous medium characteristics from micro-flow modelling. Water microflow transport processes occurring at the pore level are dependent on the microstructure of porous body and interactions between the fluid and the medium. In case of soils, i.e. the medium there exist relatively big pores in which water can move easily but also finer pores are present in which water transport processes are dominated by strong interactions between the medium and the fluid - full physical description of these phenomena is a challenge. Ten samples of different soils were scanned using X-ray computational microtomograph. The diameter of samples was 5 mm. The voxel resolution of CT scan was 2.5 µm. Resulting 3D soil samples images were used for reconstruction of the pore space for further modelling. 3D image threshholding was made to determine the soil grain surface. This surface was triangulated and used for computational mesh construction for the pore space. Numerical modelling of water flow through the

  7. Water management, agriculture, and ground-water supplies

    USGS Publications Warehouse

    Nace, Raymond L.

    1960-01-01

    Encyclopedic data on world geography strikingly illustrate the drastic inequity in the distribution of the world's water supply. About 97 percent of the total volume of water is in the world's oceans. The area of continents and islands not under icecaps, glaciers, lakes, and inland seas is about 57.5 million square miles, of which 18 million (36 percent) is arid to semiarid. The total world supply of water is about 326.5 million cubic miles, of which about 317 million is in the oceans and about 9.4 million is in the land areas. Atmospheric moisture is equivalent to only about 3,100 cubic miles of water. The available and accessible supply of ground water in the United States is somewhat more than 53,000 cubic miles (about 180 billion acre ft). The amount of fresh water on the land areas of the world at any one time is roughly 30,300 cubic miles and more than a fourth of this is in large fresh-water lakes on the North American Continent. Annual recharge of ground water in the United States may average somewhat more than 1 billion acre-feet yearly, but the total volume of ground water in storage is equivalent to all the recharge in about the last 160 years. This accumulation of ground water is the nation's only reserve water resource, but already it is being withdrawn or mined on a large scale in a few areas. The principal withdrawals of water in the United States are for agriculture and industry. Only 7.4 percent of agricultural land is irrigated, however; so natural soil moisture is the principal source of agricultural water, and on that basis agriculture is incomparably the largest water user. In view of current forecasts of population and industrial expansion, new commitments of water for agriculture should be scrutinized very closely, and thorough justification should be required. The 17 Western States no longer contain all the large irrigation developments. Nearly 10 percent of the irrigated area is in States east of the western bloc, chiefly in several

  8. Water resources data, Idaho, 2004; Volume 3. Ground water records

    USGS Publications Warehouse

    Campbell, A.M.; Conti, S.N.; O'Dell, I.

    2005-01-01

    Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 18 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

  9. Water resources data, Idaho, 2003; Volume 3. Ground water records

    USGS Publications Warehouse

    Campbell, A.M.; Conti, S.N.; O'Dell, I.

    2003-01-01

    Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

  10. Parallelized Modelling of Soil-Coupled 3D Water Uptake of Multiple Root Systems with Automatic Adaptive Time Step Control

    NASA Astrophysics Data System (ADS)

    Kalbacher, T.; Delfs, J.; Schneider, C.; Kolditz, O.; Ufz-Environmental Informatics

    2010-12-01

    Numerical modelling of interacting flow processes between roots and soil is essential for understanding the influence of different root geometries and types on the hydro-system. This technical contribution will describe the coupling of two software tools to enable the analysis of water uptake of plant communities, one modelling the water flow along a network of resistances from the bulk soil along radial soil discs towards the root system up to the root collar while the second tool is covering the non-linear dynamics of water flow within soil by a 3D-Richards model. Appropriate methods for geometric coupling, fast coupled parameter exchange and coordinated parallelization have been developed to ensure an efficient functionality. An adaptive time stepping with automatic control is introduced to guarantee the stability of the solution of non-linear problems. The development of benchmarking examples for roots-soil models with multiple root systems will be continuously and detailed reported on a new communication platform “HydroBench” for hydrological modeling.

  11. Improved water and lipid suppression for 3D PRESS CSI using RF band selective inversion with gradient dephasing (BASING).

    PubMed

    Star-Lack, J; Nelson, S J; Kurhanewicz, J; Huang, L R; Vigneron, D B

    1997-08-01

    A T1 insensitive solvent suppression technique-band selective inversion with gradient dephasing (BASING)-was developed to suppress water and lipids for 1H magnetic resonance spectroscopy (MRS). BASING, which consists of a frequency selective RF inversion pulse surrounded by spoiler gradient pulses of opposite signs, was used to dephase stopband resonances and minimally impact passband metabolites. Passband phase linearity was achieved with a dual BASING scheme. Using the Shinnar-Le Roux algorithm, a highpass filter was designed to suppress water and rephase the lactate methyl doublet independently of TE, and water/lipid bandstop filters were designed for the brain and prostate. Phantom and in vivo experimental 3D PRESS CSI data were acquired at 1.5 T to compare BASING with CHESS and STIR suppression. With BASING, the measured suppression factor was over 100 times higher than with CHESS or STIR causing baseline distortions to be removed. It was shown that BASING can be incorporated into a variety of sequences to offer improved suppression in the presence of B1 and T1 inhomogeneites.

  12. Procedures for ground-water investigations

    SciTech Connect

    Not Available

    1989-09-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water investigations are carried out to fulfill the requirements for the US Department of Energy (DOE) to meet the requirements of DOE Orders. Investigations are also performed for various clients to meet the requirements of the Resource Conservation and Recovery Act of 1976 (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). National standards including procedures published by the American Society for Testing and Materials (ASTM) and the US Geological Survey were utilized in developing the procedures contained in this manual.

  13. Ground water hydraulics as a geophysical aid

    USGS Publications Warehouse

    Ferris, John G.

    1948-01-01

    The publication of the non-equilibrium formula in 1935 in a paper by Theis marked the opening of a new era in the analysis and understanding of the hydraulics of percolating ground waters. Through the past decade 9 an ever-increasing number of engineers and geologists have become familiar-with the application of this formula to practical problems of ground-water flow and have tested it in the field, against precise observations, under controlled conditions. Although the highly idealized aquifer assumed for the derivation of this formula is not of widespread occurrence in the field, we gain increasing confidence in the use of the Theis method as our backlog of proven data accumulates until we now look askance at test data which do not conform to this theory. In many cases, careful study of these anomalous data will reveal the means for estimating the degree or manner in which an observed aquifer diverges from the idealized aquifer.

  14. REGIONAL GROUND-WATER-QUALITY NETWORK DESIGN.

    USGS Publications Warehouse

    Templin, William E.; ,

    1985-01-01

    This paper describes the approach used in designing a regional network to monitor the complex ground-water-quality conditions in the San Joaquin Valley, California. The actual network approximates the ideal network with the constraint of primarily using wells that are already being monitored by someone for some purpose. Further inventories of monitoring networks and installation of some specialized monitoring wells will be needed. Use of statistical network analysis techniques is also needed to make network improvements. Following these actions, the actual network will more closely approximate the ideal network in providing information on ground-water-quality trends, contaminant sources, prevention of future sources of contamination, monitoring well distributions, sampling frequencies, and constituents to be monitored.

  15. Coupled surface-water and ground-water model

    USGS Publications Warehouse

    Swain, Eric D.; Wexler, Eliezer J.

    1991-01-01

    In areas with dynamic and hydraulically well connected ground-water and surface-water systems, it is desirable that stream-aquifer interaction be simulated with models of equal sophistication and accuracy. Accordingly, a new, coupled ground-water and surface-water model was developed by combining the U.S. Geological Survey models MODFLOW and BRANCH. MODFLOW is the widely used modular three-dimensional, finite-difference, ground-water model and BRANCH is a one-dimensional numerical model commonly used to simulate flow in open-channel networks. Because time steps used in ground-water modeling commonly are much longer than those used in surface-water simulations, provision has been made for handling multiple BRANCH time steps within one MODFLOW time step. Verification testing of the coupled model was done using data from previous studies and by comparing results with output from a simpler four-point implicit open-channel flow model linked with MODFLOW.

  16. Regional Analysis of Ground-Water Recharge

    USGS Publications Warehouse

    Flint, Lorraine E.; Flint, Alan L.

    2007-01-01

    A modeling analysis of runoff and ground-water recharge for the arid and semiarid southwestern United States was performed to investigate the interactions of climate and other controlling factors and to place the eight study-site investigations into a regional context. A distributed-parameter water-balance model (the Basin Characterization Model, or BCM) was used in the analysis. Data requirements of the BCM included digital representations of topography, soils, geology, and vegetation, together with monthly time-series of precipitation and air-temperature data. Time-series of potential evapotranspiration were generated by using a submodel for solar radiation, taking into account topographic shading, cloudiness, and vegetation density. Snowpack accumulation and melting were modeled using precipitation and air-temperature data. Amounts of water available for runoff and ground-water recharge were calculated on the basis of water-budget considerations by using measured- and generated-meteorologic time series together with estimates of soil-water storage and saturated hydraulic conductivity of subsoil geologic units. Calculations were made on a computational grid with a horizontal resolution of about 270 meters for the entire 1,033,840 square-kilometer study area. The modeling analysis was composed of 194 basins, including the eight basins containing ground-water recharge-site investigations. For each grid cell, the BCM computed monthly values of potential evapotranspiration, soil-water storage, in-place ground-water recharge, and runoff (potential stream flow). A fixed percentage of runoff was assumed to become recharge beneath channels operating at a finer resolution than the computational grid of the BCM. Monthly precipitation and temperature data from 1941 to 2004 were used to explore climatic variability in runoff and ground-water recharge. The selected approach provided a framework for classifying study-site basins with respect to climate and dominant recharge

  17. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... result in contamination of ground water which may be needed or used for human consumption. This finding... water supplies; (vi) The existing quality of the ground water, including other sources of contamination... result in the contamination of ground water which may be needed or used for human consumption. Such...

  18. Ground water in Myrtle Creek - Glendale area, Douglas County, Oregon

    USGS Publications Warehouse

    Frank, F.J.

    1979-01-01

    The purpose of this report is to describe briefly the occurence of ground water and to present ground-water information that will help water users, public officials, and planners to determine the probability of obtaining adequate quanitities of good-quality ground water in the Myrtle Creek-Glendale area.

  19. Hydrogeology, water quality, and ground-water-development alternatives in the Upper Wood River Ground-Water Reservoir, Rhode Island. Water resources investigations

    SciTech Connect

    Dickerman, D.C.; Bell, R.W.

    1993-12-31

    This report describes the hydrogeology, water quality, and ground-water-development alternatives in the upper Wood River ground-water reservoir, Rhode Island. The report includes discussion of (1) recharge to and hydraulic properties of the stratified-drift aquifer, (2) stream-aquifer interconnection, (3) assessment of the quality of ground water and surface water, (4) input to and calibration of a two-dimensional ground-water-flow model, and (5) results of simulations of the effect of alternative ground-water-development schemes on ground-water levels and streamflow.

  20. Ground Water Atlas of the United States

    USGS Publications Warehouse

    ,

    2000-01-01

    PrefaceThe Ground Water Atlas of the United States presents a comprehensive summary of the Nation's ground-water resources and is a basic reference for the location, geography, geology, and hydrologic characteristics of the major aquifers in the Nation. The information was collected by the U.S. Geological Survey and other agencies during the course of many years of study. Results of the Regional Aquifer-System Analysis Program, a systematic study of the Nation's major aquifers by the U.S. Geological Survey, were used as a major, but not exclusive, source of information of the Atlas. The Atlas, which is designed in a graphical format that is supported by descriptive discussions, includes 13 chapters, each representing areas that collectively cover the 50 States and Puerto Rico, as well as the U.S. Virgin Islands. Each chapter of the Atlas presents and describes hydrogeologic and hydrologic conditions for the major aquifers in each regional area. The scale of the Atlas does not allow portrayal of minor features of the geology or hydrology of each aquifer presented, nor does it include detailed discussion of minor aquifers. Those readers who seek detailed local information for the aquifers will find extensive lists of references at the end of each chapter. The introductory chapter in this volume presents an overview of ground-water conditions Nationwide and gives an example of an aquifer in each of six hydrogeologic settings.

  1. Ground water in the Cuyama Valley, California

    USGS Publications Warehouse

    Upson, J.E.; Worts, George Frank

    1951-01-01

    This is the fourth of a series of interpretive reports on the water resources of the major valleys of Santa Barbara County, Calif., prepared by the Geological Survey, United States Department of the Interior, in cooperation with Santa Barbara County. The first three reports described the other major valleys in the county: the south-coast basins, Goleta and Carpinteria, and the Santa Maria and Santa Ynez River valleys. This report deals with the Cuyama Valley in the northeastern part of the county and adjoining parts of San Luis Obispo, Kern, and Ventura Counties. It includes estimates of natural discharge, pumpage, and yield of ground water, and all data on water levels, well records, and water quality that were available up to June 1946.

  2. Thrust faulting and 3D ground deformation of the 3 July 2015 Mw 6.4 Pishan, China earthquake from Sentinel-1A radar interferometry

    NASA Astrophysics Data System (ADS)

    Sun, Jianbao; Shen, Zheng-Kang; Li, Tao; Chen, Jie

    2016-06-01

    Boosted by the launch of Sentinel-1A radar satellite from the European Space Agency (ESA), we now have the opportunity of fast, full and multiple coverage of the land based deformation field of earthquakes. Here we use the data to investigate a strong earthquake struck Pishan, western China on July 3, 2015. The earthquake fault is blind and no ground break features are found on-site, thus Synthetic Aperture Radar (SAR) data give full play to its technical advantage for the recovery of coseismic deformation field. By using the Sentinel-1A radar data in the Interferometric Wide Swath mode, we obtain 3 tracks of InSAR data over the struck region, and resolve the 3D ground deformation generated by the earthquake. Then the Line-of-Sight (LOS) InSAR data are inverted for the slip-distribution of the seismogenic fault. The final model shows that the earthquake is completely blind with pure-thrust motion. The maximum slip is 0.48 m at a depth of 7 km, consistent with the depth estimate from seismic reflection data. In particular, the inverted model is also compatible with a south-dipping fault ramp among a group of fault interfaces detected by the seismic reflection profile over the region. The seismic moment obtained equals to a Mw 6.4 earthquake. The Pishan earthquake ruptured the frontal part of the thrust ramps under the Slik anticline, and unloaded the coulomb stress of them. However, it may have loaded stress to the back-thrust above the thrust ramps by 1-4 bar, and promoted it for future failure. Moreover, the stress loading on the west side of the earthquake fault is much larger than that on the east side, indicating a higher risk for failure to the west of the Zepu fault.

  3. Azimuthal filter to attenuate ground roll noise in the F-kx-ky domain for land 3D-3C seismic data with uneven acquisition geometry

    NASA Astrophysics Data System (ADS)

    Arevalo-Lopez, H. S.; Levin, S. A.

    2016-12-01

    The vertical component of seismic wave reflections is contaminated by surface noise such as ground roll and secondary scattering from near surface inhomogeneities. A common method for attenuating these, unfortunately often aliased, arrivals is via velocity filtering and/or multichannel stacking. 3D-3C acquisition technology provides two additional sources of information about the surface wave noise that we exploit here: (1) areal receiver coverage, and (2) a pair of horizontal components recorded at the same location as the vertical component. Areal coverage allows us to segregate arrivals at each individual receiver or group of receivers by direction. The horizontal components, having much less compressional reflection body wave energy than the vertical component, provide a template of where to focus our energies on attenuating the surface wave arrivals. (In the simplest setting, the vertical component is a scaled 90 degree phase rotated version of the radial horizontal arrival, a potential third possible lever we have not yet tried to integrate.) The key to our approach is to use the magnitude of the horizontal components to outline a data-adaptive "velocity" filter region in the w-Kx-Ky domain. The big advantage for us is that even in the presence of uneven receiver geometries, the filter automatically tracks through aliasing without manual sculpting and a priori velocity and dispersion estimation. The method was applied to an aliased synthetic dataset based on a five layer earth model which also included shallow scatterers to simulate near-surface inhomogeneities and successfully removed both the ground roll and scatterers from the vertical component (Figure 1).

  4. Ground water discharge and the related nutrient and trace metal fluxes into Quincy Bay, Massachusetts

    USGS Publications Warehouse

    Poppe, L.J.; Moffett, A.M.

    1993-01-01

    Measurement of the rate and direction of ground water flow beneath Wollaston Beach, Quincy, Massachusetts by use of a heat-pulsing flowmeter shows a mean velocity in the bulk sediment of 40 cm d-1. The estimated total discharge of ground water into Quincy Bay during October 1990 was 1324-2177 m3 d-1, a relatively low ground Water discharge rate. The tides have only a moderate effect on the rate and direction of this flow. Other important controls on the rate and volume of ground water flow are the limited thickness, geographic extent, and permeability of the aquifer. Comparisons of published streamflow data and estimates of ground water discharge indicate that ground water makes up between 7.4-12.1% of the gaged freshwater input into Quincy Bay. The data from this study suggest the ground water discharge is a less important recharge component to Quincy Bay than predicted by National Urban Runoff Program (NURP) models. The high nitrate and low nitrite and ammonia concentrations in the ground water at the backshore we]l sites and low nitrate and high nitrite and ammonia concentrations in the water flowing from the foreshore suggests that denitrification is active in the sediments. The low ground water flow rates and low nitrate concentrations in the foreshore samples suggest that little or no nitrate is surviving the denitrification process to affect the planktonic community. Similarly, oxidizing conditions in the aquifer and low trace metal concentrations in the ground water samples suggest that the metals may be precipitating and binding to sedimentary phases before impacting the bay.

  5. Estimation of the Above Ground Biomass of Tropical Forests using Polarimetric and Tomographic SAR Data Acquired at P Band and 3-D Imaging Techniques

    NASA Astrophysics Data System (ADS)

    Ferro-Famil, L.; El Hajj Chehade, B.; Ho Tong Minh, D.; Tebaldini, S.; LE Toan, T.

    2016-12-01

    Developing and improving methods to monitor forest biomass in space and time is a timely challenge, especially for tropical forests, for which SAR imaging at larger wavelength presents an interesting potential. Nevertheless, directly estimating tropical forest biomass from classical 2-D SAR images may reveal a very complex and ill-conditioned problem, since a SAR echo is composed of numerous contributions, whose features and importance depend on many geophysical parameters, such has ground humidity, roughness, topography… that are not related to biomass. Recent studies showed that SAR modes of diversity, i.e. polarimetric intensity ratios or interferometric phase centers, do not fully resolve this under-determined problem, whereas Pol-InSAR tree height estimates may be related to biomass through allometric relationships, with, in general over tropical forests, significant levels of uncertainty and lack of robustness. In this context, 3-D imaging using SAR tomography represents an appealing solution at larger wavelengths, for which wave penetration properties ensures a high quality mapping of a tropical forest reflectivity in the vertical direction. This paper presents a series of studies led, in the frame of the preparation of the next ESA mission BIOMASS, on the estimation of biomass over a tropical forest in French Guiana, using Polarimetric SAR Tomographic (Pol-TomSAR) data acquired at P band by ONERA. It is then shown that Pol-TomoSAR significantly improves the retrieval of forest above ground biomass (AGB) in a high biomass forest (200 up to 500 t/ha), with an error of only 10% at 1.5-ha resolution using a reflectivity estimates sampled at a predetermined elevation. The robustness of this technique is tested by applying the same approach over another site, and results show a similar relationship between AGB and tomographic reflectivity over both sites. The excellent ability of Pol-TomSAR to retrieve both canopy top heights and ground topography with an error

  6. EVALUATING THE EFFECTIVENESS OF GROUND WATER EXTRACTION SYSTEMS (JOURNAL)

    EPA Science Inventory

    The most common process for remediating contaminated ground water is extraction and treatment. Data from 19 ongoing and completed ground water extraction systems were collected and analyzed to evaluate the effectiveness of this process in achieving cleanup concentration goals for...

  7. EVALUATING THE EFFECTIVENESS OF GROUND WATER EXTRACTION SYSTEMS (JOURNAL)

    EPA Science Inventory

    The most common process for remediating contaminated ground water is extraction and treatment. Data from 19 ongoing and completed ground water extraction systems were collected and analyzed to evaluate the effectiveness of this process in achieving cleanup concentration goals for...

  8. Ground water in Creek County, Oklahoma

    USGS Publications Warehouse

    Cady, Richard Carlysle

    1937-01-01

    Creek County has been designated as a problem area by the Land Use Planning Section of the Resettlement Administration. Some of the earliest oil fields to brought into production were situated in and near this county, and new fields have been opened from time to time during the ensuing years. The production of the newer fields, however, has not kept pace with the exhaustion of the older fields, and the county now presents an excellent picture of the problems involved in adjusting a population to lands that are nearly depleted of their mineral wealth. Values of land have been greatly depressed; tax collection is far in arrears; tenancy is widespread; and in addition more people will apparently be forced to depend on the income from agriculture than the land seems capable of supporting. The county as a whole is at best indifferently suitable for general farming. The Land Use planning Section proposes to study the present and seemingly immanent maladjustments of population to the resources of the land, and make recommendations for their correction. The writer was detailed to the Land Use Planning Section of Region VIII for the purposes of making studies of ground water problems in the region. In Creek County two investigations were made. In September, 1936, the writer spent about ten days investigating the availability of ground water for the irrigation of garden crops during drouths. If it proved feasible to do this generally throughout the county, the Land Use Planning Section might be able to encourage this practice. The second investigation made by the writer was in regard to the extent to which ground water supplies have been damaged by oil well brines. He was in county for four days late in January 1937, and again in March, 1937. During part of the second field trip he was accompanied by R.M. Dixon, sanitary engineer of the Water Utilization Unit of the Resettlement Administration. (available as photostat copy only)

  9. 3-D Numerical Modeling as a Tool for Managing Mineral Water Extraction from a Complex Groundwater Basin in Italy

    NASA Astrophysics Data System (ADS)

    Zanini, A.; Tanda, M.

    2007-12-01

    The groundwater in Italy plays an important role as drinking water; in fact it covers about the 30% of the national demand (70% in Northern Italy). The mineral water distribution in Italy is an important business with an increasing demand from abroad countries. The mineral water Companies have a great interest in order to increase the water extraction, but for the delicate and complex geology of the subsoil, where such very high quality waters are contained, a particular attention must be paid in order to avoid an excessive lowering of the groundwater reservoirs or great changes in the groundwater flow directions. A big water Company asked our University to set up a numerical model of the groundwater basin, in order to obtain a useful tool which allows to evaluate the strength of the aquifer and to design new extraction wells. The study area is located along Appennini Mountains and it covers a surface of about 18 km2; the topography ranges from 200 to 600 m a.s.l.. In ancient times only a spring with naturally sparkling water was known in the area, but at present the mineral water is extracted from deep pumping wells. The area is characterized by a very complex geology: the subsoil structure is described by a sequence of layers of silt-clay, marl-clay, travertine and alluvial deposit. Different groundwater layers are present and the one with best quality flows in the travertine layer; the natural flow rate seems to be not subjected to seasonal variations. The water age analysis revealed a very old water which means that the mineral aquifers are not directly connected with the meteoric recharge. The Geologists of the Company suggest that the water supply of the mineral aquifers comes from a carbonated unit located in the deep layers of the mountains bordering the spring area. The valley is crossed by a river that does not present connections to the mineral aquifers. Inside the area there are about 30 pumping wells that extract water at different depths. We built a 3

  10. Worldwide occurrences of arsenic in ground water

    USGS Publications Warehouse

    Nordstrom, D. Kirk

    2002-01-01

    Numerous aquifers worldwide carry soluble arsenic at concentrations greater than the World Health Organization--and U.S. Environmental Protection Agency--recommended drinking water standard of 10 mg per liter. Sources include both natural (black shales, young sediments with low flushing rates, gold mineralization, and geothermal environments) and anthropogenic (mining activities, livestock feed additives, pesticides, and arsenic trioxide wastes and stockpiles). Increased solubility and mobility of arsenic is promoted by high pH (>8.5), competing oxyanions, and reducing conditions. In this Policy Forum, Nordstrom argues that human health risks from arsenic in ground water can be minimized by incorporating hydrogeochemical knowledge into water management decisions and by more careful monitoring for arsenic in geologically high-risk areas.

  11. Natural radionuclides in Hanford site ground waters

    SciTech Connect

    Smith, M.R.; Laul, J.C.; Johnson, V.G.

    1987-10-01

    Uranium, Th, Ra, Rn, Pb and Po radionuclide concentrations in ground waters from the Hanford Site indicate that U, Th, and Ra are highly sorbed. Relative to Rn, these radionuclides are low by factors of 10/sup -3/ to 10/sup -6/. Uranium sorption is likely due to its reduction from the +6 state, where it is introduced via surface waters, to the +4 state found in the confined aquifers. The distribution of radionuclides is very similar in all of the confined aquifers and significantly different from the distribution observed in the unconfined and surface waters. Barium correlates well with Ra over three orders of magnitude, indicating that stable element analogs may be useful for inferring the behavior of radioactive waste radionuclides in this candidate geologic repository. 8 refs., 7 figs., 1 tab.

  12. Estimating ground water yield in small research basins

    Treesearch

    Elon S. Verry

    2003-01-01

    An analysis of ground water recharge in 32 small research watersheds shows the average flow of ground water out of the watershed (deep seepage) is 45% of streamflow and ranges from 8 to 350 mm/year when apportioned over the watershed area. It is time to meld ground water and small watershed science. The use of we11 networks and the evaluation of ground water well...

  13. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... that ensures detection of ground-water contamination in the uppermost aquifer. When physical obstacles... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51...

  14. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  15. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  16. Ground water and small research basins: an historical perspective

    Treesearch

    Elon S. Verry

    2003-01-01

    Scientists have been studying hydrological processes within a watershed context for hundreds of years. Throughout much of that history, little attention was paid to the significance of ground water; in nearly all early studies, ground water was never considered. In many recent studies, ground water fluxes are assumed to be insignificantly small. The following is a...

  17. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the concentration...

  18. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  19. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  20. Winter Thaws Can Raise Ground Water Levels in Driftless Area

    Treesearch

    Richard S. Sartz

    1967-01-01

    Springflow and ground water levels both rose with winter thaws, even when the ground was frozen. A high soil water content suggests that water moved to the water table through a continuous column of soil water rather than as a wetting front

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

    NASA Astrophysics Data System (ADS)

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

    2004-06-01

    A 3D hydrodynamic model of the Aral Sea was successfully implemented to address the complex hydrodynamic changes induced by the combined effect of hydrologic and climatic change in the Aral region. The first barotropic numerical experiments allowed us to produce a comparative description of the mean general seasonal circulation patterns corresponding to the original situation (1956-1960) and of the average situation for the period from 1981 to 1985, a very low river flow period. The dominant anticyclonic circulation suggested by our seasonal simulation is in good agreement with previous investigations. In addition, this main anticyclonic gyre was shown to be stable and clearly established from February to September, while winter winds led to another circulation scenario. In winter, the main anticyclonic gyre was considerably limited, and cyclonic circulations appeared in the deep western basin and in the northeast of the shallow basin. In contrast, stronger anticyclonic circulation was observed in the Small Aral Sea during winter. As a consequence of the 10-m sea level drop observed between the two periods considered, the 1981-1985 simulation suggests an intensification of seasonal variability. Total water transport of the main gyre was reduced with sea level drop by a minimum of 30% in May and up to 54% in September. Before 1960, the study of the net flows through Berg and Kokaral Straits allowed us to evaluate the component of water exchange between the Small and the Large Seas linked with the general anticyclonic circulation around Kokaral Island. This exchange was lowest in summer (with a mean anticyclonic exchange of 222 m 3/s for July and August), highest in fall and winter (with a mean value of 1356 m 3/s from September to February) and briefly reversed in the spring (mean cyclonic circulation of 316 m 3/s for April and May). In summer, the water exchange due to local circulation at the scale of each strait was comparatively more important because net flows

  2. 3d-4f {Co(II)3Ln(OR)4} Cubanes as Bio-Inspired Water Oxidation Catalysts.

    PubMed

    Evangelisti, Fabio; Moré, René; Hodel, Florian; Luber, Sandra; Patzke, Greta Ricarda

    2015-09-02

    Although the {CaMn4O5} oxygen evolving complex (OEC) of photosystem II is a major paradigm for water oxidation catalyst (WOC) development, the comprehensive translation of its key features into active molecular WOCs remains challenging. The [Co(II)3Ln(hmp)4(OAc)5H2O] ({Co(II)3Ln(OR)4}; Ln = Ho-Yb, hmp = 2-(hydroxymethyl)pyridine) cubane WOC series is introduced as a new springboard to address crucial design parameters, ranging from nuclearity and redox-inactive promoters to operational stability and ligand exchange properties. The {Co(II)3Ln(OR)4} cubanes promote bioinspired WOC design by newly combining Ln(3+) centers as redox-inactive Ca(2+) analogues with flexible aqua-/acetate ligands into active and stable WOCs (max. TON/TOF values of 211/9 s(-1)). Furthermore, they open up the important family of 3d-4f complexes for photocatalytic applications. The stability of the {Co(II)3Ln(OR)4} WOCs under photocatalytic conditions is demonstrated with a comprehensive analytical strategy including trace metal analyses and solution-based X-ray absorption spectroscopy (XAS) investigations. The productive influence of the Ln(3+) centers is linked to favorable ligand mobility, and the experimental trends are substantiated with Born-Oppenheimer molecular dynamics studies.

  3. Water resources data, New Jersey, water year 2005.Volume 2 - ground-water data

    USGS Publications Warehouse

    Jones, Walter D.

    2006-01-01

    Water-resources data for the 2005 water year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water quality of streams: stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. Volume 2 contains a summary of the hydrologic conditions for 2005 water year; a listing of current water resource projects in New Jersey; a bibliography of water-related reports, articles, and fact sheets completed by the Geological Survey in recent years; records of ground-water levels from 214 wells; and a table of discontinued observation wells for which ground-water-level data are available. The locations of the ground-water level sites are shown on figure 4. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in New Jersey.

  4. Water resources data, New Jersey, water year 2004--volume 2. ground-water data

    USGS Publications Warehouse

    Jones, Walter D.

    2005-01-01

    Water-resources data for the 2004 water year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water quality of streams: stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. Volume 2 contains a summary of the hydrologic conditions for 2004 water year; a listing of current water resource projects in New Jersey; a bibliography of water-related reports, articles, and fact sheets completed by the Geological Survey in recent years; records of ground-water levels from 196 wells; and a table of discontinued observation wells for which ground-water-level data are available. The locations of the ground-water level sites are shown on figure 4. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, Sate, and local agencies in New Jersey.

  5. Water Resources Data, New Jersey, Water Year 2003 - Volume 2. Ground-Water Data

    USGS Publications Warehouse

    Jones, Walter D.

    2004-01-01

    Water-resources data for the 2003 water year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water quality of streams: stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. Volume 2 contains a summary of the hydrologic conditions for 2003 water year; a listing of current water resource projects in New Jersey; a bibliography of water-related reports, articles, and fact sheets completed by the Geological Survey in recent years; records of ground-water levels from 185 wells; and a table of discontinued observation wells for which ground-water-level data are available. The locations of the ground-water level sites are shown on figure 4. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, Sate, and local agencies in New Jersey.

  6. Studies of Grounding Line Migration Over Rutofrd Ice Stream Using 3D Short Repeat-Time Series From Multi-Track InSAR Acquisitions.

    NASA Astrophysics Data System (ADS)

    Milillo, P.; Minchew, B. M.; Riel, B. V.; Simons, M.; Gardner, A. S.; Agram, P. S.

    2015-12-01

    It has long been known that basal mechanics of ice streams are sensitive to short- timescale hourly to seasonal forcings, such as water pressure fluctuations and tidal loading as well as long-timescale (yearly to decadal) thinning. Designing SAR short repeat time observations to cover nearly an entire test-site in Antarctica from ascending and descending orbital directions, using every available SAR satellite is fundamental for understanding a new class of phenomena, underlying the physics of glaciers and ice streams. Understanding grounding-line dynamics is necessary for predictions of long-term ice-sheet stability. However, despite growing observations of the tidal influence on grounding-line migration, this short-timescale migration is poorly understood, with most modeling attempts assuming beam theory to calculate displacements. Knowing the position of the grounding line with accuracy is important for the global mass balance of ice sheets or for quantitatively modeling the mechanical interaction between ice shelves and ice sheets. Here we present a general method for retrieving three dimensional displacement vector given a set of multiple tracks, multiple geometry SAR acquisitions. The algorithm extends the single line of sight mathematical framework to the four spatial and temporal dimensions including both range and azimuth measurements. We designed COSMO-SkyMed (CSK) observations of Rutford Ice Stream to cover nearly the grounding zone from ascending and descending orbital directions using every available CSK satellite This spatially comprehensive observational scheme allowed us to derive time series of the 3-dimensional surface displacement for the grounding zone, facilitating studies of ice stream mechanics and tidally induced grounding line migrations with unprecedented spatial extent and temporal resolution. Having a constellation with occasional 1- day repeat time and an average 4-days repeat time is beneficial when looking at displacements of more than

  7. Ground-water development in Utah and effects on ground-water levels and chemical quality

    USGS Publications Warehouse

    Gates, Joseph S.; Allen, David V.

    1996-01-01

    Systematic ground-water development began in Utah shortly after settlement by Mormon pioneers in 1847. By 1939, about 230,000 acrefeet per year of ground water was being withdrawn from wells for irrigation, public supply, industrial use, and rural-domestic and stock supply. Withdrawals increased from about 600,000 to 700,000 acre-feet per year during 1963-67 to about 800,000 to 900,000 acre-feet per year during 1989-93, with a peak of 940,000 acre-feet in 1990.Most ground-water withdrawals from wells have been from unconsolidated basin-fill deposits in 13 areas along or near the eastern edge of the Basin and Range Province, which extends from the northern edge of Utah to its southwestern part. The proportions of withdrawals for various uses have changed; in 1964, 72 percent of withdrawals was for irrigation and II percent for public supply, whereas in 1993,64 percent was for irrigation and 21 percent for public supply.Long-term withdrawals from wells have caused declines in water levels in parts of western Utah from the 1940's and 1950's to 1994; the withdrawals apparently have caused local increases in dissolved-solids concentrations in ground water. Water levels have declined as much as 67 feet owing to withdrawals for public supply and industrial use in northwestern Utah, and as much as 88 feet owing to withdrawals for irrigation in southwestern Utah. Declines of this magnitude, however, are confined to local areas of large withdrawals. Withdrawals for irrigation apparently have caused increases in dissolved-solids concentrations in ground water in at least six irrigated areas of western Utah. Minor land subsidence related to compaction of basin-fill deposits caused by water-level declines has been observed locally in southwestern Utah.

  8. 3D Anisotropic Velocity Tomography of a Water Saturated Rock under True-Triaxial Stress in the Laboratory

    NASA Astrophysics Data System (ADS)

    Ghofrani Tabari, M.; Goodfellow, S. D.; Nasseri, M. B.; Young, R.

    2013-12-01

    A cubic specimen of water saturated Fontainebleau Sandstone is tested in the laboratory under true-triaxial loading where three different principal stresses are applied under drained conditions. Due to the loading arrangement, closure and opening of the pre-existing cracks in the rock, as well as creation and growth of the aligned cracks cause elliptical anisotropy and distributed heterogeneities. A Geophysical Imaging Cell equipped with an Acoustic Emission monitoring system is employed to image velocity structure of the sample during the experiment through repeated transducer to transducer non-destructive ultrasonic surveys. Apparent P-wave velocities along the rock body are calculated in different directions and shown in stereonet plots which demonstrate an overall anisotropy of the sample. The apparent velocities in the main three orthogonal cubic directions are used as raw data for building a mean spatial distribution model of anisotropy ratios. This approach is based on the concept of semi-principal axes in an elliptical anisotropic model and appointing two ratios between the three orthogonal velocities in each of the cubic grid cells. The spatial distribution model of anisotropy ratios are used to calculate the anisotropic ray-path segment matrix elements (Gij). These contain segment lengths of the ith ray in the jth cell in three dimensions where, length of each ray in each cell is computed for one principal direction based on the dip and strike of the ray and these lengths differ from the ones in an isotropic G Matrix. 3D strain of the squeezed rock and the consequent geometrical deformation is also included in the ray-path segment matrix. A Singular Value Decomposition (SVD) method is used for inversion from the data space of apparent velocities to the model space of P-wave propagation velocities in the three principal directions. Finally, spatial variation and temporal evolution of induced damages in the rock, representing uniformly distributed or

  9. Correlative 3D-imaging of Pipistrellus penis micromorphology: Validating quantitative microCT images with undecalcified serial ground section histomorphology.

    PubMed

    Herdina, Anna Nele; Plenk, Hanns; Benda, Petr; Lina, Peter H C; Herzig-Straschil, Barbara; Hilgers, Helge; Metscher, Brian D

    2015-06-01

    Detailed knowledge of histomorphology is a prerequisite for the understanding of function, variation, and development. In bats, as in other mammals, penis and baculum morphology are important in species discrimination and phylogenetic studies. In this study, nondestructive 3D-microtomographic (microCT, µCT) images of bacula and iodine-stained penes of Pipistrellus pipistrellus were correlated with light microscopic images from undecalcified surface-stained ground sections of three of these penes of P. pipistrellus (1 juvenile). The results were then compared with µCT-images of bacula of P. pygmaeus, P. hanaki, and P. nathusii. The Y-shaped baculum in all studied Pipistrellus species has a proximal base with two club-shaped branches, a long slender shaft, and a forked distal tip. The branches contain a medullary cavity of variable size, which tapers into a central canal of variable length in the proximal baculum shaft. Both are surrounded by a lamellar and a woven bone layer and contain fatty marrow and blood vessels. The distal shaft consists of woven bone only, without a vascular canal. The proximal ends of the branches are connected with the tunica albuginea of the corpora cavernosa via entheses. In the penis shaft, the corpus spongiosum-surrounded urethra lies in a ventral grove of the corpora cavernosa, and continues in the glans under the baculum. The glans penis predominantly comprises an enlarged corpus spongiosum, which surrounds urethra and baculum. In the 12 studied juvenile and subadult P. pipistrellus specimens the proximal branches of the baculum were shorter and without marrow cavity, while shaft and distal tip appeared already fully developed. The present combination with light microscopic images from one species enabled a more reliable interpretation of histomorphological structures in the µCT-images from all four Pipistrellus species. © 2015 Wiley Periodicals, Inc.

  10. Contamination of ground water, surface water, and soil, and evaluation of selected ground-water pumping alternatives in the Canal Creek area of Aberdeen Proving Ground, Maryland

    USGS Publications Warehouse

    Lorah, Michelle M.; Clark, Jeffrey S.

    1996-01-01

    Chemical manufacturing, munitions filling, and other military-support activities have resulted in the contamination of ground water, surface water, and soil in the Canal Creek area of Aberdeen Proving Ground, Maryland. Chlorinated volatile organic compounds, including 1,1,2,2-tetrachloroethane and trichloroethylene, are widespread ground-water contaminants in two aquifers that are composed of unconsolidated sand and gravel. Distribution and fate of chlorinated organic compounds in the ground water has been affected by the movement and dissolution of solvents in their dense immiscible phase and by microbial degradation under anaerobic conditions. Detection of volatile organic contaminants in adjacent surface water indicates that shallow contaminated ground water discharges to surface water. Semivolatile organic compounds, especially polycyclic aromatic hydrocarbons, are the most prevalent organic contaminants in soils. Various trace elements, such as arsenic, cadmium, lead, and zinc, were found in elevated concentrations in ground water, surface water, and soil. Simulations with a ground-water-flow model and particle tracker postprocessor show that, without remedial pumpage, the contaminants will eventually migrate to Canal Creek and Gunpowder River. Simulations indicate that remedial pumpage of 2.0 million gallons per day from existing wells is needed to capture all particles originating in the contaminant plumes. Simulated pumpage from offsite wells screened in a lower confined aquifer does not affect the flow of contaminated ground water in the Canal Creek area.

  11. Shallow Alluvial Aquifer Ground Water System and Surface Water/Ground Water Interaction, Boulder Creek, Boulder, Colorado

    NASA Astrophysics Data System (ADS)

    Babcock, K. P.; Ge, S.; Crifasi, R. R.

    2006-12-01

    Water chemistry in Boulder Creek, Colorado, shows significant variation as the Creek flows through the City of Boulder [Barber et al., 2006]. This variation is partially due to ground water inputs, which are not quantitatively understood. The purpose of this study is (1) to understand ground water movement in a shallow alluvial aquifer system and (2) to assess surface water/ground water interaction. The study area, encompassing an area of 1 mi2, is located at the Sawhill and Walden Ponds area in Boulder. This area was reclaimed by the City of Boulder and Boulder County after gravel mining operations ceased in the 1970's. Consequently, ground water has filled in the numerous gravel pits allowing riparian vegetation regrowth and replanting. An integrated approach is used to examine the shallow ground water and surface water of the study area through field measurements, water table mapping, graphical data analysis, and numerical modeling. Collected field data suggest that lateral heterogeneity exists throughout the unconsolidated sediment. Alluvial hydraulic conductivities range from 1 to 24 ft/day and flow rates range from 0.01 to 2 ft/day. Preliminary data analysis suggests that ground water movement parallels surface topography and does not noticeably vary with season. Recharge via infiltrating precipitation is dependent on evapotranspiration (ET) demands and is influenced by preferential flow paths. During the growing season when ET demand exceeds precipitation rates, there is little recharge; however recharge occurs during cooler months when ET demand is insignificant. Preliminary data suggest that the Boulder Creek is gaining ground water as it traverses the study area. Stream flow influences the water table for distances up to 400 feet. The influence of stream flow is reflected in the zones relatively low total dissolved solids concentration. A modeling study is being conducted to synthesize aquifer test data, ground water levels, and stream flow data. The

  12. The role of ground water in sub-Saharan Africa.

    PubMed

    Braune, Eberhard; Xu, Yongxin

    2010-01-01

    Although water resources managers speak of a water crisis in Africa, the management of ground water has to date not featured strongly in national and regional African water agendas. Examination of the physical environment of the continent and, in particular, the water resources in relation to the socioeconomic landscape and regional development challenges makes it clear that widely occurring, albeit largely low-yielding, ground water resources will be crucial in the achievement of water security and development. Ground water is important primarily in domestic water and sanitation services, but also for other local productive needs like community gardens, stock watering, and brick-making, all essential to secure a basic livelihood and thus to alleviate poverty. Despite the importance of small-scale farming in Africa, there is little information on the present and potential role of ground water in agriculture. In contrast to its socioeconomic and ecological importance, ground water has remained a poorly understood and managed resource. Widespread contamination of ground water resources is occurring, and the important environmental services of ground water are neglected. There appear to be critical shortcomings in the organizational framework and the building of institutional capacity for ground water. Addressing this challenge will require a much clearer understanding and articulation of ground water's role and contribution to national and regional development objectives and an integrated management framework, with top-down facilitation of local actions.

  13. Ground-water resources of Cambodia

    USGS Publications Warehouse

    Rasmussen, William Charles; Bradford, Gary M.

    1977-01-01

    available information is on the central lowlands and contiguous low plateaus, as the mountainous areas on the west and the high plateaus on the east are relatively unexplored with respect to their ground-water availability. No persistent artesian aquifer has been identified nor have any large potential ground-water sources been found .although much of the country yet remains to be explored by test drilling. Well irrigation for garden produce is feasible on a modest scale in many localities throughout Cambodia. It does not seem likely, however, that large-scale irrigation from wells will come about in the future. Ground water may be regarded as a widely available supplemental source to surface water for domestic, small-scale industrial, and irrigation use.

  14. Heterogeneity and thermal modeling of ground water.

    PubMed

    Ferguson, Grant

    2007-01-01

    Heat transport in aquifers is becoming an increasingly important topic due to recent growth in the use of ground water in thermal applications. However, the effect of heterogeneity on heat transport in aquifers has yet to be examined in the same detail as it has been for solute transport, and it is unclear what effect this may have on our ability to create accurate models. This study examines this issue through stochastic modeling using the geostatistics for two aquifers with low and high degrees of heterogeneity. The results indicate that there is considerable uncertainty in the distribution of heat associated with injection of warm water into an aquifer. Heterogeneity in the permeability field was also found to slightly reduce the ability to recover this introduced heat at a later time. These simulations also reveal that hydrodynamic macrodispersion is an important consideration in some heat flow problems.

  15. Animating ground water levels with Excel.

    PubMed

    Shikaze, Steven G; Crowe, Allan S

    2003-01-01

    This note describes the use of Microsoft Excel macros (programs written in Excel's internal language, Visual Basic for Applications) to create simple onscreen animations of transient ground water data within Excel. Compared to many specialized visualization software packages, the use of Excel macros is much cheaper, much simpler, and can rapidly be learned. The Excel macro can also be used to create individual GIF files for each animation frame. This series of frames can then be used to create an AVI video file using any of a number of graphics packages, such as Corel PhotoPaint. The technique is demonstrated through a macro that animates changes in the elevation of a water table along a transect over several years.

  16. Monitoring for pesticides in ground water in Nevada

    USGS Publications Warehouse

    Adams, Patricia A.; Moses, Charles W.; Bevans, Hugh E.

    1997-01-01

    Many pesticides designed to control weed encroachment, plant disease, and insect predation are used in agricultural and urban areas in the United States. Contamination of ground water by pesticides has increased over the last 20 years (U.S. Environmental Protection Agency, 1992). In 1985, the U.S. Environmental Protection Agency (USEPA) estimated the detection of at least 17 agricultural pesticides in the ground water of 23 states. By 1988, pesticides identified in ground water had increased to 46 in 26 states. To protect ground water from pesticide contamination, USEPA, through the Federal Fungicide Insecticide and Rodenticide Act (FIFRA), requires all states to institute a ground-water protection program.

  17. Ground-water models: Validate or invalidate

    USGS Publications Warehouse

    Bredehoeft, J.D.; Konikow, L.F.

    1993-01-01

    The word validation has a clear meaning to both the scientific community and the general public. Within the scientific community the validation of scientific theory has been the subject of philosophical debate. The philosopher of science, Karl Popper, argued that scientific theory cannot be validated, only invalidated. Popper’s view is not the only opinion in this debate; however, many scientists today agree with Popper (including the authors). To the general public, proclaiming that a ground-water model is validated carries with it an aura of correctness that we do not believe many of us who model would claim. We can place all the caveats we wish, but the public has its own understanding of what the word implies. Using the word valid with respect to models misleads the public; verification carries with it similar connotations as far as the public is concerned. Our point is this: using the terms validation and verification are misleading, at best. These terms should be abandoned by the ground-water community.

  18. Water Resources Data, Florida, Water Year 2002, Volume 3B. Southwest Florida Ground Water

    USGS Publications Warehouse

    Kane, R.L.; Fletcher, W.L.

    2003-01-01

    Water resources data for the 2002 water year in Florida consist of continuous or daily discharges for 392 streams, periodic discharge for 15 streams, continuous daily stage for 191 streams, periodic stage for 13 streams, peak stage for 33 streams and peak discharge for 33 streams, continuous or daily elevations for 14 lakes, periodic elevations for 49 lakes; continuous ground-water levels for 418 wells, periodic ground-water levels for 1,287 wells, and quality-of-water data for 116 surface-water sites and 291 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 125 wells; periodic ground-water elevations at 31 wells; miscellaneous ground-water elevations at 377 wells; and water quality at 46 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

  19. Water Resources Data, Florida, Water Year 2001, Volume 3B. Southwest Florida Ground Water

    USGS Publications Warehouse

    Stoker, Y.E.; Kane, R.L.; Fletcher, W.L.

    2002-01-01

    Water resources data for the 2001 water year in Florida consist of continuous or daily discharges for 406 streams, periodic discharge for 12 streams, continuous daily stage for 142 streams, periodic stage for 12 streams, peak stage and discharge for 37 streams, continuous or daily elevations for 11 lakes, periodic elevations for 30 lakes; continuous ground-water levels for 424 wells, periodic ground-water levels for 1,426 wells, and quality-of-water data for 80 surface-water sites and 245 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 128 wells; periodic ground-water elevations at 33 wells; miscellaneous ground-water elevations at 347 wells; and water quality at 25 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

  20. Water Resources Data, Florida, Water Year 2003, Volume 3B: Southwest Florida Ground Water

    USGS Publications Warehouse

    Kane, Richard L.; Fletcher, William L.; Lane, Susan L.

    2004-01-01

    Water resources data for the 2003 water year in Florida consist of continuous or daily discharges for 385 streams, periodic discharge for 13 streams, continuous daily stage for 255 streams, periodic stage for 13 streams, peak stage for 36 streams and peak discharge for 36 streams, continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,227 wells, and quality-of-water data for 133 surface-water sites and 308 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 128 wells; periodic ground-water elevations at 31 wells; miscellaneous ground-water elevations at 405 wells; and water quality at 32 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

  1. Water resources data Florida, water year 2004: Volume 3B: southwest Florida ground water

    USGS Publications Warehouse

    Kane, Richard L.

    2004-01-01

    Water resources data for the 2004 water year in Florida consist of continuous or daily discharges for 405 streams, periodic discharge for 12 streams, continuous or daily stage for 159 streams, periodic stage for 19 streams, peak stage for 30 streams and peak discharge for 30 streams, continuous or daily elevations for 14 lakes, periodic elevations for 23 lakes; continuous ground-water levels for 408 wells, periodic ground-water levels for 1,188 wells, and quality-of-water data for 140 surface-water sites and 240 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 98 wells; periodic ground-water elevations at 56 wells; miscellaneous ground-water elevations at 374 wells; and water quality at 25 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

  2. Water resources data, Florida, water year 2005. Volume 3B: Southwest Florida ground water

    USGS Publications Warehouse

    Kane, Richard L.

    2005-01-01

    Water resources data for the 2005 water year in Florida consist of continuous or daily discharges for 429 streams, periodic discharge for 9 streams, continuous or daily stage for 218 streams, periodic stage for 5 streams, peak stage for 28 streams and peak discharge for 28 streams, continuous or daily elevations for 15 lakes, periodic elevations for 23 lakes; continuous ground-water levels for 401 wells, periodic ground-water levels for 1,098 wells, and quality-of-water data for 211 surface-water sites and 208 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 108 wells; periodic ground-water elevations at 24 wells; miscellaneous ground-water elevations at 354 wells; and water quality at 2 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

  3. Fast Lipid And Water Levels by Extraction with Spatial Smoothing (FLAWLESS): 3-D Volume Fat/Water Separation at 7T

    PubMed Central

    2011-01-01

    Purpose To quickly and robustly separate fat/water components of 7T MR images in the presence of field inhomogeneity for the study of metabolic disorders in small animals. Materials and Methods Starting with a Markov random field (MRF) based formulation for the three-point Dixon separation problem, we incorporated new implementation strategies, including stability tracking, multiresolution image pyramid, and improved initial value generation. We term the new method FLAWLESS (Fast Lipid And Water Levels by Extraction with Spatial Smoothing). Results Compared to non-MRF techniques, FLAWLESS decreased the fat-water swapping mistakes in all of the 3-D animal volumes that we tested. FLAWLESS converged in about 1/60th of the computation time of other MRF approaches. The initial value generation of FLAWLESS further improved robustness to field inhomogeneity in 3-D volume data. Conclusion We have developed a novel three-point Dixon technique found to be useful for high field small animal imaging. It is being used to assess lipid depots and metabolic disorders as a function of genes, diet, age, and therapy. PMID:21591017

  4. Water Resources Data North Dakota Water Year 2002, Volume 2. Ground Water

    USGS Publications Warehouse

    Harkness, R.E.; Wald, J.D.

    2003-01-01

    Water-resources data for the 2002 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 2 contains water-level records for 117 ground-water wells and water-quality records for 65 monitoring wells. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.

  5. When People Push Water Deep Under Ground, It Can Cause Repeating Ground Shakes

    NASA Astrophysics Data System (ADS)

    Brudzinski, M.; Skoumal, R.; Currie, B.

    2016-12-01

    We look for ground shakes that repeat many times using a fast computer. We can do this when people put out a box that senses ground waves and stores all of them in computer memory. When a ground shake happens, we take the wave form from the ground shake, and use the fast computer to look for any matching wave forms in all of the ground waves stored in memory. Repeating ground shakes can happen when people push water deep down into the ground, which makes it easier for rocks to slip past each other. Sometimes people really push water down deep to break tight rocks and get more stuff stored inside that we use for power. The left over water from breaking rocks is not clean so it often gets pushed down even deeper, far away from the water people drink. In 99 out of 100 cases, pushing the water deep down under ground does not cause ground shakes we can see, even with a computer. Even fewer cases can be felt by people. In the cases where the water causes ground shakes, very small repeating ground shakes often happen early on. We can use a fast computer to find these repeating ground shakes to help us know if larger ground shakes might happen.

  6. A ground-water-quality monitoring program for Nevada

    USGS Publications Warehouse

    Nowlin, Jon O.

    1986-01-01

    A program was designed for the systematic monitoring of ground-water quality in Nevada. Basic hydrologic and water-quality principles are discussed in the formulation of a rational approach to developing a statewide monitoring program. A review of ground-water monitoring efforts in Nevada through 1977 indicates that few requirements for an effective statewide program are being met. A suggested program has been developed that consists of five major elements: (1) A Background-Quality Network to assess the existing water quality in Nevada aquifers, (2) a Contamination Source Inventory of known or potential threats to ground-water quality, (3) Surveillance Networks to monitor ground-water quality in selected hydrographic areas, (4) Intensive Surveys of individual instances of known or potential ground-water contamination, and (5) Ground-Water Data File to manage data generated by the other monitoring elements. Two indices have been developed to help assign rational priorities for monitoring ground water in the 255 hydrographic areas of Nevada: (1) A Hydrographic-Area Priority Index for surveillance monitoring, and (2) A Development-Potential Index for background monitoring of areas with little or no current development. Requirements for efficient management of data from ground-water monitoring are discussed and the three major systems containing Nevada ground-water data are reviewed. More than 11,000 chemical analyses of ground water have been acquired from existing systems and incorporated into a prototype data base.

  7. α-Fe2O3/TiO2 3D hierarchical nanostructures for enhanced photoelectrochemical water splitting.

    PubMed

    Han, Hyungkyu; Riboni, Francesca; Karlicky, Frantisek; Kment, Stepan; Goswami, Anandarup; Sudhagar, Pitchaimuthu; Yoo, Jeongeun; Wang, Lei; Tomanec, Ondrej; Petr, Martin; Haderka, Ondrej; Terashima, Chiaki; Fujishima, Akira; Schmuki, Patrik; Zboril, Radek

    2017-01-07

    We report the fabrication of 3D hierarchical hetero-nanostructures composed of thin α-Fe2O3 nanoflakes branched on TiO2 nanotubes. The novel α-Fe2O3/TiO2 hierarchical nanostructures, synthesized on FTO through a multi-step hydrothermal process, exhibit enhanced performances in photo-electrochemical water splitting and in the photocatalytic degradation of an organic dye, with respect to pure TiO2 nanotubes. An enhanced separation of photogenerated charge carriers is here proposed as the main factor for the observed photo-activities: electrons photogenerated in TiO2 are efficiently collected at FTO, while holes are transferred to the α-Fe2O3 nanobranches that serve as charge mediators to the electrolyte. The morphology of α-Fe2O3 that varies from ultrathin nanoflakes to nanorod/nanofiber structures depending on the Fe precursor concentration was shown to have a significant impact on the photo-induced activity of the α-Fe2O3/TiO2 composites. In particular, it is shown that for an optimized photo-electrochemical structure, a combination of critical factors should be achieved such as (i) TiO2 light absorption and photo-activation vs.α-Fe2O3-induced shadowing effect and (ii) the availability of free TiO2 surface vs.α-Fe2O3-coated surface. Finally, theoretical analysis, based on DFT calculations, confirmed the optical properties experimentally determined for the α-Fe2O3/TiO2 hierarchical nanostructures. We anticipate that this new multi-step hydrothermal process can be a blueprint for the design and development of other hierarchical heterogeneous metal oxide electrodes suitable for photo-electrochemical applications.

  8. Protecting ground water: pesticides and agricultural practices. Technical report (Final)

    SciTech Connect

    Not Available

    1988-02-01

    The booklet presents the results of a project conducted by EPA's Office of Ground-Water Protection to evaluate the potential impacts of various agronomic, irrigation, and pesticide application practices on ground water. The report provides State and local water quality and agricultural officials with technical information to help in the development of programs to protect ground water from pesticide contamination. The report explains the principles involved in reducing the risk of pesticide contamination and describes what is known about the impact of various agricultural practices on pesticide leaching. It is hoped that the information will be helpful to water-quality officials in developing and implementing ground-water protection programs.

  9. Hydrogeology and Ground-Water Flow in the Opequon Creek Watershed area, Virginia and West Virginia

    USGS Publications Warehouse

    Kozar, Mark D.; Weary, David J.

    2009-01-01

    model to develop a realistic simulation of ground-water flow in the larger Opequon Creek watershed area. In the model, recharge for average hydrologic conditions was 689 m3/d/km2 (cubic meters per day per square kilometer) over the entire Opequon Creek watershed area. Mean and median measured base flows at the streamflow-gaging station on the Opequon Creek near Martinsburg, West Virginia, were 604,384 and 349,907 m3/d (cubic meters per day), respectively. The simulated base flow of 432,834 m3/d fell between the mean and median measured stream base flows for the station. Simulated base-flow yields for subwatersheds during average conditions ranged from 0 to 2,643 m3/d/km2, and the median for the entire Opequon Creek watershed area was 557 m3/d/km2. A drought was simulated by reducing model recharge by 40 percent, a rate that approximates the recharge during the prolonged 16-month drought that affected the region from November 1998 to February 2000. Mean and median measured streamflows for the Opequon Creek watershed area at the Martinsburg, West Virginia, streamflow-gaging station during the 1999 drought were 341,098 and 216,551 m3/d, respectively. The simulated drought base flow at the station of 252,356 m3/d is within the range of flows measured during the 1999 drought. Recharge was 413 m3/d/km2 over the entire watershed during the simulated drought, and was 388 m3/d/km2 at the gaging station. Simulated base-flow yields for drought conditions ranged from 0 to 1,865 m3/d/km2 and averaged 327 m3/d/km2 over the entire Opequon Creek watershed. Water budgets developed from the simulation results indicate a substantial component of direct ground-water discharge to the Potomac River. This phenomenon had long been suspected but had not been quantified. During average conditions, approximately 564,176 m3/d of base flow discharges to the Potomac River. An additional 124,379 m3/d of ground water is also estimated to discharge directly to the Potomac River and rep

  10. Using Averaging-Based Factorization to Compare Seismic Hazard Models Derived from 3D Earthquake Simulations with NGA Ground Motion Prediction Equations

    NASA Astrophysics Data System (ADS)

    Wang, F.; Jordan, T. H.

    2012-12-01

    Seismic hazard models based on empirical ground motion prediction equations (GMPEs) employ a model-based factorization to account for source, propagation, and path effects. An alternative is to simulate these effects directly using earthquake source models combined with three-dimensional (3D) models of Earth structure. We have developed an averaging-based factorization (ABF) scheme that facilitates the geographically explicit comparison of these two types of seismic hazard models. For any fault source k with epicentral position x, slip spatial and temporal distribution f, and moment magnitude m, we calculate the excitation functions G(s, k, x, m, f) for sites s in a geographical region R, such as 5% damped spectral acceleration at a particular period. Through a sequence of weighted-averaging and normalization operations following a certain hierarchy over f, m, x, k, and s, we uniquely factorize G(s, k, x, m, f) into six components: A, B(s), C(s, k), D(s, k, x), E(s, k, x, m), and F(s, k, x, m, f). Factors for a target model can be divided by those of a reference model to obtain six corresponding factor ratios, or residual factors: a, b(s), c(s, k), d(s, k, x), e(s, k, x, m), and f(s, k, x, m, f). We show that these residual factors characterize differences in basin effects primarily through b(s), distance scaling primarily through c(s, k), and source directivity primarily through d(s, k, x). We illustrate the ABF scheme by comparing CyberShake Hazard Model (CSHM) for the Los Angeles region (Graves et. al. 2010) with the Next Generation Attenuation (NGA) GMPEs modified according to the directivity relations of Spudich and Chiou (2008). Relative to CSHM, all NGA models underestimate the directivity and basin effects. In particular, the NGA models do not account for the coupling between source directivity and basin excitation that substantially enhance the low-frequency seismic hazards in the sedimentary basins of the Los Angeles region. Assuming Cyber

  11. Water resources data, North Carolina, water year 2003. Volume 2: Ground-water records

    USGS Publications Warehouse

    Howe, S.S.; Breton, P.L.; Chapman, M.J.

    2004-01-01

    Water-resources data for the 2003 water year for North Carolina consist of records of stage, discharge, water quality for streams; stage and contents for lakes and reservoirs; precipitation; and ground-water levels and water quality of ground water. Volume 1 contains discharge records for 213 gaging stations; stage for 61 gaging stations; and continuous precipitation at 118 sites. Volume 2 contains ground-water-level data from 143 observation wells and ground-water-quality data from 72 wells. The collection of water-resources data in North Carolina is a part of the National Water-Data System operated by the U.S. Geological Survey in cooperation with State, municipal, and Federal agencies.

  12. 3_D modeling using TLS and GPR techniques to characterize above and below-ground wood distribution in pyroclastic deposits along the Blanco River (Chilean Patagonia)

    NASA Astrophysics Data System (ADS)

    Valdebenito, Galo; Tonon, Alessia; Iroume, Andrés; Alvarado, David; Fuentes, Carlos; Picco, Lorenzo; Lenzi, Mario

    2016-04-01

    origin, suggesting that these elements were generated by toppling and breaking of surrounding dead trees. Results obtained with the GPR confirm the ability of this instrument to localize the presence and distribution of buried wood. From the 3-D analysis it was possible to assess the spatial distribution and to estimate, as first approach, the volume of the buried wood which represents approximately 0.04% of the entire volcanic deposit. Further analysis will focus on additional GPR calibration with different wood sizes for a more accurate estimation of the volume. The knowledge of the overall wood amount stored in a fluvial system that can be remobilized over time, represent an essential factor to ensure better forest and river management actions.

  13. Constructing a novel hierarchical 3D flower-like nano/micro titanium phosphate with efficient hydrogen evolution from water splitting

    NASA Astrophysics Data System (ADS)

    Guo, Si-yao; Han, Song

    2014-12-01

    A novel nano/micro hierarchical structured titanium phosphate with unique 3D flower-like morphology has been prepared by a simple hydrothermal method without adding any surfactants. The shape of the titanium phosphate could be controlled by simply adjusting the concentration of phosphoric acid. The 3D flower-like titanium phosphate with diameter of 2-3 μm is characterized by the assembly of numerous porous and connected lamella structures. Interestingly, this novel hierarchical mesoporous 3D flower-like titanium exhibits enhanced hydrogen evolution from water splitting under xenon lamp irradiation in the presence of methanol as the sacrificial reagent, which is also the first example of 3D flower-like titanium phosphate with high photocatalytic activity for water splitting. Since the use of titanium phosphate as a photocatalyst has been mostly neglected up to now, this low-cost, simple procedure and large-scale yield of 3D nano/micro structure titanium phosphate could be expected to be applicable in the synthesis of controlled, reproducible and robust photocatalytic systems.

  14. Ground-Water Availability in the United States

    USGS Publications Warehouse

    Reilly, Thomas E.; Dennehy, Kevin F.; Alley, William M.; Cunningham, William L.

    2008-01-01

    Ground water is among the Nation's most important natural resources. It provides half our drinking water and is essential to the vitality of agriculture and industry, as well as to the health of rivers, wetlands, and estuaries throughout the country. Large-scale development of ground-water resources with accompanying declines in ground-water levels and other effects of pumping has led to concerns about the future availability of ground water to meet domestic, agricultural, industrial, and environmental needs. The challenges in determining ground-water availability are many. This report examines what is known about the Nation's ground-water availability and outlines a program of study by the U.S. Geological Survey Ground-Water Resources Program to improve our understanding of ground-water availability in major aquifers across the Nation. The approach is designed to provide useful regional information for State and local agencies who manage ground-water resources, while providing the building blocks for a national assessment. The report is written for a wide audience interested or involved in the management, protection, and sustainable use of the Nation's water resources.

  15. KT3D_H2O: a program for kriging water level data using hydrologic drift terms.

    PubMed

    Karanovic, Marinko; Tonkin, Matthew; Wilson, David

    2009-01-01

    It is often necessary to estimate the zone of contribution to, or the capture zone developed by, pumped wells: for example, when evaluating pump-and-treat remedies and when developing wellhead protection areas for supply wells. Tonkin and Larson (2002) and Brochu and Marcotte (2003) describe a mapping-based method for estimating the capture zone of pumped wells, developed by combining universal kriging (kriging with a trend) with analytical expressions that describe the response of the potentiometric surface to certain applied stresses. This Methods Note describes (a) expansions to the technique described by Tonkin and Larson (2002); (b) the concept of the capture frequency map (CFM), a technique that combines information from multiple capture zone maps into a single depiction of capture; (c) the development of a graphical user interface to facilitate the use of the methods described; and (d) the integration of these programs within the MapWindow geographic information system environment. An example application is presented that illustrates ground water level contours, capture zones, and a CFM prepared using the methods and software described.

  16. 3-D visualization of geologic structures and processes

    NASA Astrophysics Data System (ADS)

    Pflug, R.; Klein, H.; Ramshorn, Ch.; Genter, M.; Stärk, A.

    Interactive 3-D computer graphics techniques are used to visualize geologic structures and simulated geologic processes. Geometric models that serve as input to 3-D viewing programs are generated from contour maps, from serial sections, or directly from simulation program output. Choice of viewing parameters strongly affects the perception of irregular surfaces. An interactive 3-D rendering program and its graphical user interface provide visualization tools for structural geology, seismic interpretation, and visual post-processing of simulations. Dynamic display of transient ground-water simulations and sedimentary process simulations can visualize processes developing through time.

  17. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-water contamination in the uppermost aquifer. The relevant point of compliance specified by the Director... of the ground water, including other sources of contamination and their cumulative impacts on the... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Ground-water monitoring systems....

  18. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an underground drinking water source beyond the solid waste boundary or beyond an alternative boundary specified...

  19. Geology and occurrence of ground water in Lyon County, Minnesota

    USGS Publications Warehouse

    Rodis, Harry G.

    1963-01-01

    Large quantities of ground water are available from melt-water channels in the county. Moderate quantities, adequate for domestic and small industrial needs, are available from many of the small isolated deposits of sand and gravel in the till. Small quantities of ground water, adequate only for domestic supply, generally can be obtained from Cretaceous sandstone.

  20. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an underground drinking water source beyond the solid waste boundary or beyond an alternative boundary specified...

  1. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an underground drinking water source beyond the solid waste boundary or beyond an alternative boundary specified...

  2. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an underground drinking water source beyond the solid waste boundary or beyond an alternative boundary specified...

  3. Ground-water resources of Rusk County, Texas

    USGS Publications Warehouse

    Sandeen, W.M.

    1984-01-01

    Some mineralization of ground water is due to natural causes. Other mineralization of ground water is due to contamination. A program needs to be initiated to determine the extent and cause of mineralization that has taken place in freshwater sands. Water-quality data is needed at Henderson in order to monitor saltwater encroachment.

  4. Progress in ground-water protection and restoration

    SciTech Connect

    Not Available

    1990-02-01

    Since issuing EPA's 'Ground-Water Protection Strategy' in 1984, the Agency has made significant strides in the protection of ground-water resources, both in implementing the ground-water related statutory authorities and in developing new EPA initiatives and activities. States also have made great progress in developing their own ground-water protection strategies and wellhead protection programs. Despite the progress already made in the protection and restoration of ground water, as documented in the report, much remains to be done--especially with respect to preventing pollution of ground-water resources. On July 18, 1989, a ground-water task force with the primary goal to develop a strategy for the direction EPA will take in ground-water protection. The strategy will incorporate recommendations and initiatives to ensure effective and consistent decision-making in all Agency actions affecting the resource, guide us as we deal with future ground-water issues, and assure that a clean and safe source of water will be available to all Americans and to the ecological systems on which we depend.

  5. Ground-Water Hydrology of the Upper Deschutes Basin, Oregon

    USGS Publications Warehouse

    Gannett, Marshall W.; Lite, Kenneth E.; Morgan, David S.; Collins, Charles A.

    2001-01-01

    The upper Deschutes Basin is among the fastest growing regions in Oregon. The rapid population growth has been accompanied by increased demand for water. Surface streams, however, have been administratively closed to additional appropriation for many years, and surface water is not generally available to support new development. Consequently, ground water is being relied upon to satisfy the growth in water demand. Oregon water law requires that the potential effects of ground-water development on streamflow be evaluated when considering applications for new ground-water rights. Prior to this study, hydrologic understanding has been insufficient to quantitatively evaluate the connection between ground water and streamflow, and the behavior of the regional ground-water flow system in general. This report describes the results of a hydrologic investigation undertaken to provide that understanding. The investigation encompasses about 4,500 square miles of the upper Deschutes River drainage basin.A large proportion of the precipitation in the upper Deschutes Basin falls in the Cascade Range, making it the principal ground-water recharge area for the basin. Water-balance calculations indicate that the average annual rate of ground- water recharge from precipitation is about 3,500 ft3/s (cubic feet per second). Water-budget calculations indicate that in addition to recharge from precipitation, water enters the ground-water system through interbasin flow. Approximately 800 ft3/s flows into the Metolius River drainage from the west and about 50 ft3/s flows into the southeastern part of the study area from the Fort Rock Basin. East of the Cascade Range, there is little or no ground-water recharge from precipitation, but leaking irrigation canals are a significant source of artificial recharge north of Bend. The average annual rate of canal leakage during 1994 was estimated to be about 490 ft3/s. Ground water flows from the Cascade Range through permeable volcanic rocks

  6. Calibration of the DRASTIC ground water vulnerability mapping method

    USGS Publications Warehouse

    Rupert, M.G.

    2001-01-01

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

  7. A New Method of Absorption-Phase Nanotomography for 3D Observation of Mineral-Organic-Water Textiles and its Application to Pristine Carbonaceous Chondrites

    NASA Technical Reports Server (NTRS)

    Tsuchiyama, A.; Nakato, A.; Matsuno, J.; Sugimoto, M.; Uesugi, K.; Takeuchi, A.; Nakano, T.; Vaccaro, E.; Russel, S.; Nakamura-Messenger, K.; hide

    2017-01-01

    Pristine carbonaceous chondrites contain fine-grained matrix, which is composed largely of amorphous silicates, sub-micron silicate and sulfide crystals, and organic materials. They are regarded as primitive dust in the early Solar System that have suffered minimal alteration in their parent bodies. The matrix generally has different lithologies; some of them are unaltered but some are more or less aqueously altered. Their textures have been examined in 2D usually by FE-SEM/EDS, TEM/EDS, nano-SIMS and micro-XRD. Observation of their complex fine textures, such as spatial relation between different lithologies in 3D, is important for understanding aggregation and alteration processes. Synchrotron radiation (SR)-based X-ray tomography reveals 3D structures nondestructively with high spatial resolution of approximately greater than 100 nm. We have developed a new technique using absorption contrasts called "dual-energy tomography" (DET) to obtain 3D distribution of minerals at SPring-8, SR facility in Japan, and applied successfully to Itokawa particles. Phase and absorption contrast images can be simultaneously obtained in 3D by using "scanning-imaging x-ray microscopy" (SIXM) at SPring-8, which can discriminate between void, water and organic materials. We applied this technique combined with FIB micro-sampling to carbonaceous chondrites to search for primitive liquid water. In this study, we combined the DET and SIXM to obtain three dimensional submicron-scale association between minerals, organic materials and water and applied this to pristine carbonaceous chondrites.

  8. An application of thermometry to the study of ground water

    USGS Publications Warehouse

    Schneider, Robert

    1962-01-01

    The precise measurement of fluctuations in ground-water temperature, based on monthly readings in shallow glacial-outwash aquifers (up to about 70 feet deep), is useful in the study of ground-water movement and recharge. In addition to the study of natural phenomena in the hydrologic cycle, thermometry may be used as a tool in making detailed studies of (1) the effects of inducing the infiltration of surface water, (2) artificial recharge, (3) the effects of injecting petroleum products or radioactive or other wastes into the ground, and (4) ground-water movement in mines.

  9. Hanford Site environmental data for calendar year 1991 -- Ground water

    SciTech Connect

    Dresel, P.E.; Bates, D.J.; Merz, J.K.

    1993-03-01

    This report tabulates ground-water radiological and chemical data reported for calendar year 1991 by the Ground-Water Surveillance Project, Resource Conservation and Recovery Act (RCRA) Monitoring, and Operational Monitoring. The Ground-Water Surveillance Project is conducted by the Pacific Northwest Laboratory and the RCRA and Operational Monitoring Projects are conducted by the Westinghouse Hanford Company. This document supplements the reports Hanford Site Ground-Water Monitoring for 1991 (Evans et al. 1992) and Hanford Site Environmental Report for Calendar Year 1991 (Woodruff and Hanf 1992). The data listings provided here were generated from the Hanford Environmental Information System database.

  10. Hanford Site environmental data for calendar year 1990 -- Ground water

    SciTech Connect

    Dresel, P.E.; Bates, D.J.; Merz, J.K.

    1993-03-01

    This report tabulates ground-water radiological and chemical data for calendar year 1990 by the Ground-Water Surveillance Project, reported Resource Conservation and Recovery Act (RCRA) Monitoring, and Operational Monitoring. The Ground-Water Surveillance Project is conducted by the Pacific Northwest Laboratory and the RCRA and Operational Monitoring Projects are conducted by the Westinghouse Hanford Company. This document supplements the reports Hanford Site Ground-Water Monitoring for 1990 (Evans et al. 1992) and mental Report for Calendar Year 1990 (Woodruff and Hanf 1991). The data listings provided here were generated from the Hanford Environmental Information System database.

  11. Georgia's Ground-Water Resources and Monitoring Network, 2008

    USGS Publications Warehouse

    ,

    2008-01-01

    Ground water is an abundant resource in Georgia, providing 1.45 billion gallons per day, or 22 percent, of the total freshwater used (including thermoelectric) in the State (Fanning, 2003). Contrasting geologic features and landforms of the physiographic provinces of Georgia affect the quantity and quality of ground water throughout the State. Most ground-water withdrawals are in the Coastal Plain in the southern one-half of the State, where aquifers are highly productive. For a more complete discussion of the State's ground-water resources, see Leeth and others (2005).

  12. An overview of ground-water quality data in Wisconsin

    USGS Publications Warehouse

    Kammerer, Phil A.

    1984-01-01

    This report contains a summary of ground-water-quality data for Wisconsin and an evaluation of the adequacy of these data for assessing the impact of land disposal of wastes on ground-water quality. Chemical analyses used in data summaries were limited to those stored in the USGS computer system (WATSTORE). Information on documented instances of ground-water contamination and sources of potential contamination from land disposal of wastes was provided by the Wisconsin Department of Natural Resources. Available data provide an overview of ground water quality but may be insufficient for assessment of ground-water contamination from land disposal of wastes. Many sources of potential ground-water contamination (landfills, surface waste-storage impoundments, and buried tanks) are known. Some of these are probably causing local ground-water contamination that is not apparent from available regional data. Information needs for assessment of ground-water contamination from land disposal of wastes include improved understanding of both ground-water hydrology and the chemical behavior of specific contaminants in the environment. (USGS)

  13. Adsorption, Dissociation, and Dehydrogenation of Water Monomer and Water Dimer on the Smallest 3D Aluminum Particle. The O-H Dissociation Barrier Disappears for the Dimer.

    PubMed

    Moc, Jerzy

    2016-11-03

    We present a detailed mechanistic study on the interaction and reaction of water monomer and water dimer with the smallest 3D aluminum particle (Al6) by employing density functional and explicitly correlated coupled cluster CCSD(T)-F12 theories. Water adsorption, dissociation, and dehydrogenation are considered. For the monomer reaction, where core-valence correlation and an extrapolation to the complete basis set limit is allowed for, our coupled cluster calculations predict the O-H dissociation barrier of about 2 kcal/mol. For the dimer reaction, two distinct reaction paths are identified, initiated by forming separate dimer complexes wherein (H2O)2 adsorbs mainly via the oxygen atom of the donor H2O molecule. The key O-H dissociation transition states of the dimer reaction involve a concerted migration of two H atoms resulting in the dissociation of the donor molecule and formation of the OH-water complex adsorbed on the metal cluster's surface. The most remarkable feature of both dimer reaction energy profiles is the lack of the overall energy barrier for the (rate-determining) O-H dissociation. The hydrogen bond acceptor molecule is suggested to have an extra catalytic effect on the O-H dissociation barrier of the hydrogen bond donor molecule by removing this barrier. A similar effect on the dehydrogenation step is indicated.

  14. Ground-water availability and water quality, Farmington, Connecticut

    USGS Publications Warehouse

    Mazzaferro, David L.

    1980-01-01

    The strataified-drift aquifer in Farmington, Conn., is capable of yielding large amounts of water to individual wells. About 14 square miles of Farmington is underlain by stratified-drift deposits which, in places, are more than 450 feet thick. The most productive deposits are found in the Farmington River valley, from Unionville to River Glen, and along Scott Swamp Brook. In these areas, saturated, coarse-grained, stratified-drift deosits exceed 80 feet in thickness and estimated yields to individual wells ranged from 250 to 1,000 gallons per minute. Results of mathematical model analysis of three of the most favorable ground-water areas indicate that long-term yields range from 1.2 to 2.5 million gallons per day. Water in the Framington and Pequabuck Rivers meets the Connecticut Drinking Water Standards, assuming complete conventional treatment, for coliform orgaisms, color, trubidity, chloride, copper, and nitrate. Coliform bacteria concentrations in the Pequabuck river (12-month geometric mean of about 6,800 colonies per 100 milliliters of water) indicate a potential problem. Water in the stratified-drift aquifer is of good quality with the exception of manganese; 10 of 11 wells sampled had maganese concentrations above 0.05 milligram per liter. (USGS)

  15. 3D and beyond

    NASA Astrophysics Data System (ADS)

    Fung, Y. C.

    1995-05-01

    This conference on physiology and function covers a wide range of subjects, including the vasculature and blood flow, the flow of gas, water, and blood in the lung, the neurological structure and function, the modeling, and the motion and mechanics of organs. Many technologies are discussed. I believe that the list would include a robotic photographer, to hold the optical equipment in a precisely controlled way to obtain the images for the user. Why are 3D images needed? They are to achieve certain objectives through measurements of some objects. For example, in order to improve performance in sports or beauty of a person, we measure the form, dimensions, appearance, and movements.

  16. Ground-water conditions in Utah, spring of 2008

    USGS Publications Warehouse

    Burden, Carole B.; Allen, David V.; Danner, M.R.; Fisher, Martel J.; Freeman, Michael L.; Downhour, Paul; Wilkowske, C.D.; Eacret, Robert J.; Enright, Michael; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.

    2008-01-01

    This is the forty-fifth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2007. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs.gov/publications/GW2008.pdf.

  17. Ground-water conditions in Utah, spring of 2009

    USGS Publications Warehouse

    Burden, Carole B.; Allen, David V.; Rowland, Ryan C.; Fisher, Martel J.; Freeman, Michael L.; Downhour, Paul; Nielson, Ashley; Eacret, Robert J.; Myers, Andrew; Slaugh, Bradley A.; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.

    2009-01-01

    This is the forty-sixth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2008. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights. utah.gov/techinfo/ and http://ut.water.usgs.gov/publications/ GW2009.pdf.

  18. Ground-water conditions in Utah, spring of 2007

    USGS Publications Warehouse

    Burden, Carole B.; Allen, David V.; Danner, M.R.; Enright, Michael; Cillessen, J.L.; Gerner, S.J.; Eacret, Robert J.; Downhour, Paul; Slaugh, Bradley A.; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.; Fisher, Martel J.

    2007-01-01

    This is the forty-fourth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2006. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights.utah. gov/ and http://ut.water.usgs.gov/newUTAH/GW2007.pdf.

  19. Land subsidence caused by ground water withdrawal in urban areas

    USGS Publications Warehouse

    Holzer, T.L.; Johnson, A.I.

    1985-01-01

    At least eight urban areas in the world have encountered significant economic impact from land subsidence caused by pumping of ground water from unconsolidated sediment. The areas, most of which are coastal, include Bangkok, Houston, Mexico City, Osaka, San Jose, Shanghai, Tokyo, and Venice. Flooding related to decreased ground elevation is the principal adverse effect of the subsidence. Lesser effects include regional tilting, well-casing failures, "rising" buildings, and ground failure or rupture. Subsidence of most of these urban areas began before the phenomenon was discovered and understood. Thus, the subsidence problems were unanticipated. Methods to arrest subsidence typically have included control of ground water pumping and development of surface water to offset the reductions of ground water pumping. Ground water recharge has also been practiced. Areas threatened by flooding have been protected by extensive networks of dikes and sea walls, locks, and pumping stations to remove storm runoff. ?? 1985 D. Reidel Publishing Company.

  20. Ground-water monitoring in the Albuquerque area

    USGS Publications Warehouse

    Thorn, Condé R.

    1996-01-01

    At present (1996), all drinking water for Albuquerque residents comes from ground-water reserves. The Albuquerque area is the largest population center in the State and the largest consumer of ground water. Recent reports concerning the water resources of the Albuquerque area suggest that the Albuquerque Basin may soon face serious water-availability and water-quality problems due to anticipated ground-water development. Recent studies completed by the U.S. Geological Survey (USGS) have improved the understanding of the ground-water resources in the Albuquerque Basin. These studies have indicated that the more permeable units within the aquifer system--the upper Santa Fe Group--are less extensive than previously thought, and that water-levels have declined as much as 160 feet.

  1. Guide to North Dakota's Ground-Water Resources

    USGS Publications Warehouse

    Paulson, Q.F.

    1983-01-01

    Ground water, the water we pump from the Earth through wells or that which flows naturally from springs, is one of North Dakota's most valuable resources. More than 60 percent of the people living in the State use ground water for one purpose of another. It is the only source of water for thousands of farm families and their livestock. Almost all smaller cities and villages depend solely on groudn water as a source of supply. Increasingly, ground water is being used to irrigate crops and grasslands (fig. 1) during protracted dry spells so common in North Dakota. During recent years there has been a rapid development of rural water ditribution systems in which thousands of farms and rurals residences are connected via underground pipeline to a single water source, usually wells pumping ground water.

  2. Hanford Site ground-water monitoring for 1994

    SciTech Connect

    Dresel, P.E.; Thorne, P.D.; Luttrell, S.P.

    1995-08-01

    This report presents the results of the Ground-Water Surveillance Project monitoring for calendar year 1994 on the Hanford Site, Washington. Hanford Site operations from 1943 onward produced large quantities of radiologic and chemical waste that have impacted ground-water quality on the Site. Monitoring of water levels and ground-water chemistry is performed to track the extent of contamination and trends in contaminant concentrations. The 1994 monitoring was also designed to identify emerging ground-water quality problems. The information obtained is used to verify compliance with applicable environmental regulations and to evaluate remedial actions. Data from other monitoring and characterization programs were incorporated to provide an integrated assessment of Site ground-water quality. Additional characterization of the Site`s geologic setting and hydrology was performed to support the interpretation of contaminant distributions. Numerical modeling of sitewide ground-water flow also supported the overall project goals. Water-level monitoring was performed to evaluate ground-water flow directions, to track changes in water levels, and to relate such changes to changes in site disposal practices. Water levels over most of the Hanford Site continued to decline between June 1993 and June 1994. These declines are part of the continued response to the cessation of discharge to U Pond and other disposal facilities. The low permeability in this area which enhanced mounding of waste-water discharge has also slowed the response to the reduction of disposal.

  3. Cortical Dynamics of Figure-Ground Separation in Response to 2D Pictures and 3D Scenes: How V2 Combines Border Ownership, Stereoscopic Cues, and Gestalt Grouping Rules

    PubMed Central

    Grossberg, Stephen

    2016-01-01

    The FACADE model, and its laminar cortical realization and extension in the 3D LAMINART model, have explained, simulated, and predicted many perceptual and neurobiological data about how the visual cortex carries out 3D vision and figure-ground perception, and how these cortical mechanisms enable 2D pictures to generate 3D percepts of occluding and occluded objects. In particular, these models have proposed how border ownership occurs, but have not yet explicitly explained the correlation between multiple properties of border ownership neurons in cortical area V2 that were reported in a remarkable series of neurophysiological experiments by von der Heydt and his colleagues; namely, border ownership, contrast preference, binocular stereoscopic information, selectivity for side-of-figure, Gestalt rules, and strength of attentional modulation, as well as the time course during which such properties arise. This article shows how, by combining 3D LAMINART properties that were discovered in two parallel streams of research, a unified explanation of these properties emerges. This explanation proposes, moreover, how these properties contribute to the generation of consciously seen 3D surfaces. The first research stream models how processes like 3D boundary grouping and surface filling-in interact in multiple stages within and between the V1 interblob—V2 interstripe—V4 cortical stream and the V1 blob—V2 thin stripe—V4 cortical stream, respectively. Of particular importance for understanding figure-ground separation is how these cortical interactions convert computationally complementary boundary and surface mechanisms into a consistent conscious percept, including the critical use of surface contour feedback signals from surface representations in V2 thin stripes to boundary representations in V2 interstripes. Remarkably, key figure-ground properties emerge from these feedback interactions. The second research stream shows how cells that compute absolute disparity

  4. Cortical Dynamics of Figure-Ground Separation in Response to 2D Pictures and 3D Scenes: How V2 Combines Border Ownership, Stereoscopic Cues, and Gestalt Grouping Rules.

    PubMed

    Grossberg, Stephen

    2015-01-01

    The FACADE model, and its laminar cortical realization and extension in the 3D LAMINART model, have explained, simulated, and predicted many perceptual and neurobiological data about how the visual cortex carries out 3D vision and figure-ground perception, and how these cortical mechanisms enable 2D pictures to generate 3D percepts of occluding and occluded objects. In particular, these models have proposed how border ownership occurs, but have not yet explicitly explained the correlation between multiple properties of border ownership neurons in cortical area V2 that were reported in a remarkable series of neurophysiological experiments by von der Heydt and his colleagues; namely, border ownership, contrast preference, binocular stereoscopic information, selectivity for side-of-figure, Gestalt rules, and strength of attentional modulation, as well as the time course during which such properties arise. This article shows how, by combining 3D LAMINART properties that were discovered in two parallel streams of research, a unified explanation of these properties emerges. This explanation proposes, moreover, how these properties contribute to the generation of consciously seen 3D surfaces. The first research stream models how processes like 3D boundary grouping and surface filling-in interact in multiple stages within and between the V1 interblob-V2 interstripe-V4 cortical stream and the V1 blob-V2 thin stripe-V4 cortical stream, respectively. Of particular importance for understanding figure-ground separation is how these cortical interactions convert computationally complementary boundary and surface mechanisms into a consistent conscious percept, including the critical use of surface contour feedback signals from surface representations in V2 thin stripes to boundary representations in V2 interstripes. Remarkably, key figure-ground properties emerge from these feedback interactions. The second research stream shows how cells that compute absolute disparity in

  5. Characteristic of the Nanoparticles Formed on the Carbon Steel Surface Contacting with 3d-Metal Water Salt Solutions in the Open-Air System

    NASA Astrophysics Data System (ADS)

    Lavrynenko, O. M.; Pavlenko, O. Yu; Shchukin, Yu S.

    2016-02-01

    The contact of a steel electrode with water dispersion medium in an open-air system leads to the development of various polymorphic iron oxides and oxyhydroxides on the steel surface. Whereas the usage of distilled water causes the obtaining of Fe(II)-Fe(III) layered double hydroxides (green rust) as a primary mineral phase, but in the presence of inorganic 3d-metal water salt solutions, mixed layered double hydroxides (LDHs) together with non-stoichiometric spinel ferrite nanoparticles are formed on the steel surface. Mixed LDHs keep stability against further oxidation and complicate the obtaining of spinel ferrite nanoparticles. Thermal treatment of mixed LDHs among other mineral phases formed via the rotation-corrosion dispergation process at certain temperatures permits to obtain homogenous nanoparticles of spinel ferrites as well as maghemite or hematite doped by 3d-metal cations.

  6. Characteristic of the Nanoparticles Formed on the Carbon Steel Surface Contacting with 3d-Metal Water Salt Solutions in the Open-Air System.

    PubMed

    Lavrynenko, O M; Pavlenko, O Yu; Shchukin, Yu S

    2016-12-01

    The contact of a steel electrode with water dispersion medium in an open-air system leads to the development of various polymorphic iron oxides and oxyhydroxides on the steel surface. Whereas the usage of distilled water causes the obtaining of Fe(II)-Fe(III) layered double hydroxides (green rust) as a primary mineral phase, but in the presence of inorganic 3d-metal water salt solutions, mixed layered double hydroxides (LDHs) together with non-stoichiometric spinel ferrite nanoparticles are formed on the steel surface. Mixed LDHs keep stability against further oxidation and complicate the obtaining of spinel ferrite nanoparticles. Thermal treatment of mixed LDHs among other mineral phases formed via the rotation-corrosion dispergation process at certain temperatures permits to obtain homogenous nanoparticles of spinel ferrites as well as maghemite or hematite doped by 3d-metal cations.

  7. Calculation of Local Water Densities in Biological Systems — A Comparison of Molecular Dynamics Simulations and the 3D-RISM-KH Molecular Theory of Solvation

    PubMed Central

    Stumpe, Martin C.; Blinov, Nikolay; Wishart, David; Kovalenko, Andriy; Pande, Vijay S.

    2010-01-01

    Water plays a unique role in all living organisms. Not only is it nature’s ubiquitous solvent, but it also actively takes part in many cellular processes. In particular, the structure and properties of interfacial water near biomolecules like proteins are often related to the function of the respective molecule. It can therefore be highly instructive to study the local water density around solutes in cellular systems, particularly when solvent-mediated forces like the hydrophobic effect are relevant. Computational methods like molecular dynamics (MD) simulations seem well suited to study these systems at the atomic level. However, due to sampling requirements, it is not clear that MD simulations are indeed the method of choice to obtain converged densities at a given level of precision. We here compare the calculation of local water densities with two different methods, MD simulations and the three-dimensional reference interaction site model with the Kovalenko-Hirata closure (3D-RISM-KH). In particular, we investigate the convergence of the local water density to assess the required simulation times for different levels of resolution. Moreover, we provide a quantitative comparison of the densities calculated with MD and with 3D-RISM-KH, and investigate the effect of the choice of the water model for both methods. Our results show that 3D-RISM-KH yields density distributions that are very similar to those from MD up to a 0.5 Å resolution, but for significantly reduced computational cost. The combined use of MD and 3D-RISM-KH emerges as an auspicious perspective for efficient solvent sampling in dynamical systems. PMID:21174421

  8. Experimental Investigation of 2D thermal signature and 3D X-Ray Computed Tomography in contrasting Wettable and Water-Repellent Beads

    NASA Astrophysics Data System (ADS)

    Alsih, Abdulkareem; Flavel, Richard; McGrath, Gavan

    2017-04-01

    This study presents experimental results investigating spatial patterns of infiltration and evaporation in heterogeneous water repellent media. Infrared camera measurements and 3D X-ray computed tomography imaging was performed across wet-dry cycles on glass beads with engineered patches of water repellence. The imaging revealed spatial variability in infiltration and the redistribution of water in the media resulting in differences in relative evaporation rates during drying. It appears that the spatial organization of the heterogeneity play a role in the breakdown of water repellence at the interface of the two media. This suggests a potential mechanism for self-organization of repellency spatial patterns in field soils. At the interface between wettable and water repellent beads a lateral drying front propagates towards the wettable beads from the repellent beads. During this drying the relative surface temperatures change from a relatively cooler repellent media surface to a relatively cooler wettable media surface indicating the changes in evaporative water loss between the beads of varying water repellence. The lateral drying front was confirmed using thermography in a small-scale model of glass beads with chemically induced repellence and then subjected to 3D X-ray imaging. Pore-scale imaging identified the hydrology at the interface of the two media and at the drying front giving insights into the physics of water flow in water repellent soil.

  9. Water resources data, Maryland and Delaware, water year 1997, volume 2. ground-water data

    USGS Publications Warehouse

    Smigaj, Michael J.; Saffer, Richard W.; Starsoneck, Roger J.; Tegeler, Judith L.

    1998-01-01

    The Water Resources Division of the U.S. Geological Survey, in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Maryland and Delaware each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the U.S. Geological Survey, the data are published annually in this report series entitled 'Water Resources Data - Maryland and Delaware.' This series of annual reports for Maryland and Delaware began with the 1961 water year with a report that contained only data relating to the quantities of surface water. For the 1964 water year, a similar report was introduced that contained only data relating to water quality. Beginning with the l975 water year, the report format was changed to present, in one volume, data on quantities of surface water, quality of surface and ground water, and ground-water levels. In the 1989 water year, the report format was changed to two volumes. Both volumes contained data on quantities of surface water, quality of surface and ground water, and ground-water levels. Volume 1 contained data on the Atlantic Slope Basins (Delaware River thru Patuxent River) and Volume 2 contained data on the Monongahela and Potomac River basins. Beginning with the 1991 water year, Volume 1 contains all information on quantities of surface water and surface- water-quality data and Volume 2 contains ground-water levels and ground-water-quality data. This report is Volume 2 in our 1998 series and includes records of water levels and water quality of ground-water wells and springs. It contains records for water levels at 397 observation wells, discharge data for 6 springs, and water quality at 107 wells. Location of ground-water level wells are shown on figures 3 and 4. The location for the ground-water-quality sites are shown on figures 5

  10. Specific conductance identifies perched and ground water lakes.

    Treesearch

    Clarence F. Hawkinson; Elon S. Verry

    1975-01-01

    Shows that lakes can be classified into perched, ground water, and transitional categories according to specific conductance values. Confirms the classification with 10 years of water table measurements in 29 wells and discusses several applications of lake specific conductance values.

  11. Ground-water conditions in Utah, spring of 2005

    USGS Publications Warehouse

    Burden, Carole B.; Allen, David V.; Danner, M.R.; Walzem, Vince; Cillessen, J.L.; Kenney, T.A.; Wilkowske, C.D.; Eacret, Robert J.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Fisher, M.J.

    2005-01-01

    This is the forty-second in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, provide data to enable inter­ested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water with­drawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2004. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights and Division of Water Resources. This report is available online at http://www.waterrights.utah.gov/techinfo/ wwwpub/gw2005.pdf and http://ut.water.usgs.gov/publications/GW2005.pdf.

  12. Water resources data for North Carolina, water year 1995. Volume 2. Ground-water records. Water data report (Annual), 1 October 1994-30 September 1995

    SciTech Connect

    Smith, D.G.; George, E.D.; Breton, P.L.

    1996-06-01

    Water-resources data for the 1995 water year for North Carolina consist of records of ground-water levels and water quality of ground water; records of stage, discharge, and water quality of streams; and stage and contents of lakes and reservoirs. This report contains ground-water level data from 81 observation wells and ground-water quality data from 125 wells.

  13. Water resources data for North Carolina, water year 1993. Volume 2. Ground-water records. Water-data report (Annual), 1 October 1992-30 September 1993

    SciTech Connect

    Coble, R.W.; Smith, D.G.; Ragland, B.C.

    1994-04-13

    Water-resources data for the 1993 water year for North Carolina consist of records of ground-water levels and water quality of ground water; records of stage, discharge and water quality of streams; and stage and contents of lakes and reservoirs. This report contains ground-water level data from 82 observation wells and ground-water quality data from 41 wells.

  14. Ground Water in the Southern Lihue Basin, Kauai, Hawaii

    USGS Publications Warehouse

    Izuka, Scot K.; Gingerich, Stephen B.

    1998-01-01

    A multi-phased study of ground-water resources, including well drilling, aquifer tests, analysis of ground-water discharge, and numerical ground-water modeling, indicates that the rocks of the southern Lihue Basin, Kauai, have permeabilities that are much lower than in most other areas of ground-water development in the Hawaiian islands. The regional hydraulic conductivity of the Koloa Volcanics, which dominates fresh ground-water flow in the basin, is about 0.275 foot per day. The Waimea Canyon Basalt which surrounds the basin and underlies the Koloa Volcanics within the basin is intruded by dikes that reduce the bulk hydraulic conductivity of the rocks to about 1.11 feet per day. The low permeabilities result in steeper head gradients compared with other areas in the Hawaiian islands, and a higher proportion of ground-water discharging to streams than to the ocean. Water levels rise from near sea level at the coast to several hundreds of feet above sea level at the center of the basin a few miles inland. The high inland water levels are part of a completely saturated ground-water system. Because of the low regional hydraulic conductivity and high influx of water from recharge in the southern Lihue Basin, the rocks become saturated nearly to the surface and a variably saturated/unsaturated (perched) condition is not likely to exist. Streams incising the upper part of the aquifer drain ground water and keep the water levels just below the surface in most places. Streams thus play an important role in shaping the water table in the southern Lihue Basin. At least 62 percent of the ground water discharging from the aquifer in the southern Lihue Basin seeps to streams; the remainder seeps directly to the ocean or is withdrawn by wells.

  15. Ground water in the Thousand Oaks area, Ventura County, California

    USGS Publications Warehouse

    French, James J.

    1980-01-01

    The ground-water basin beneath the city of Thousand Oaks, Calif. , corresponds closely in area with the surface-water drainage basin of Conejo Valley. Before World War II there was little ground-water development. After World War II, urban development put a stress on the ground-water basin; many wells were drilled and water levels in wells were drawn down as much as 300 feet in places. Beginning in 1963, imported water replaced domestic and municipal ground-water systems, and water levels rapidly recovered to predevelopment levels or nearly so. Most of the ground water in the Thousand Oaks area is stored in fractured basalt of the middle Miocene Conejo Volcanics. Depending on the degree of occurrence of open fractures and cavities in the basalt, recoverable ground water in the upper 300 to 500 feet of aquifer is estimated to be between 400,000 and 600,000 acre-feet. The yield of water from wells in the area ranges from 17 to 1,080 gallons per minute. Most of the ground-water in the eastern part of the valley is high insulfate and has a dissolved-solids concentration greater than 1,000 milligrams per liter. In the western part of the valley the ground-water is mostly of a bicarbonate type, and the dissolved-solids concentration is less than 800 milligrams per liter. In most areas of Conejo Valley, ground-water is a viable resource for irrigation of public lands and recreation areas. (USGS)

  16. QUANTIFYING UNCERTAINTIES IN GROUND MOTION SIMULATIONS FOR SCENARIO EARTHQUAKES ON THE HAYWARD-RODGERS CREEK FAULT SYSTEM USING THE USGS 3D VELOCITY MODEL AND REALISTIC PSEUDODYNAMIC RUPTURE MODELS

    SciTech Connect

    Rodgers, A; Xie, X

    2008-01-09

    This project seeks to compute ground motions for large (M>6.5) scenario earthquakes on the Hayward Fault using realistic pseudodynamic ruptures, the USGS three-dimensional (3D) velocity model and anelastic finite difference simulations on parallel computers. We will attempt to bound ground motions by performing simulations with suites of stochastic rupture models for a given scenario on a given fault segment. The outcome of this effort will provide the average, spread and range of ground motions that can be expected from likely large earthquake scenarios. The resulting ground motions will be based on first-principles calculations and include the effects of slip heterogeneity, fault geometry and directivity, however, they will be band-limited to relatively low-frequency (< 1 Hz).

  17. Ferroelectric switchable behavior through fast reversible de/adsorption of water spirals in a chiral 3D metal-organic framework.

    PubMed

    Dong, Xi-Yan; Li, Bo; Ma, Bin-Bin; Li, Shi-Jun; Dong, Ming-Ming; Zhu, Yan-Yan; Zang, Shuang-Quan; Song, You; Hou, Hong-Wei; Mak, Thomas C W

    2013-07-17

    A polar homochiral 3D MOF [{Co2(L)(bpe)(H2O)}·5H2O]n constructed with cobalt(II) and a new ligand N-(1,3-dicarboxy-5-benzyl)-carboxymethylglycine (H4L) accommodates ordered helical water streams in its helical grooves. It provides the first example of switchable ferroelectric and optical behavior through two-step reversible single-crystal to single-crystal transformation (SCSC) upon desorption/adsorption of water spirals and coordinated water molecules, respectively.

  18. 3D mapping of reinforcement and tendon ducts on pre-stressed concrete bridges by means of Ground Penetrating Radar (GPR)

    NASA Astrophysics Data System (ADS)

    Cheilakou, E.; Theodorakeas, P.; Koui, M.; Zeris, C.

    2014-03-01

    The present study evaluates the potential of GPR for the inspection of pre-stressed concrete bridges and its usefulness to provide non visible information of the interior structural geometry and condition, required for strengthening and rehabilitation purposes. For that purpose, different concrete blocks of varying dimensions with embedded steel reinforcement bars, tendon ducts and fabricated voids, were prepared and tested by means of GPR in a controlled laboratory environment. 2D data acquisition was carried out in reflection mode along single profile lines of the samples in order to locate the internal structural elements. 3D surveys were also performed in a grid format both along horizontal and vertical lines, and the individual profiles collected were interpolated and further processed using a 3D reconstruction software, in order to provide a detailed insight into the concrete structure. The obtained 2D profiles provided the accurate depth and position of the embedded rebars and tendon ducts, verifying the original drawings. 3D data cubes were created enabling the presentation of depth slices and providing additional information such as shape and localization of the internal elements. The results obtained from this work showed the effectiveness and reliability of the GPR technique for pre-stressed concrete bridge investigations.

  19. Latin hypercube approach to estimate uncertainty in ground water vulnerability

    USGS Publications Warehouse

    Gurdak, J.J.; McCray, J.E.; Thyne, G.; Qi, S.L.

    2007-01-01

    A methodology is proposed to quantify prediction uncertainty associated with ground water vulnerability models that were developed through an approach that coupled multivariate logistic regression with a geographic information system (GIS). This method uses Latin hypercube sampling (LHS) to illustrate the propagation of input error and estimate uncertainty associated with the logistic regression predictions of ground water vulnerability. Central to the proposed method is the assumption that prediction uncertainty in ground water vulnerability models is a function of input error propagation from uncertainty in the estimated logistic regression model coefficients (model error) and the values of explanatory variables represented in the GIS (data error). Input probability distributions that represent both model and data error sources of uncertainty were simultaneously sampled using a Latin hypercube approach with logistic regression calculations of probability of elevated nonpoint source contaminants in ground water. The resulting probability distribution represents the prediction intervals and associated uncertainty of the ground water vulnerability predictions. The method is illustrated through a ground water vulnerability assessment of the High Plains regional aquifer. Results of the LHS simulations reveal significant prediction uncertainties that vary spatially across the regional aquifer. Additionally, the proposed method enables a spatial deconstruction of the prediction uncertainty that can lead to improved prediction of ground water vulnerability. ?? 2007 National Ground Water Association.

  20. EPA Research Evaluating CAFO Impacts on Ground Water Quality

    EPA Science Inventory

    An overview of several projects will be presented on a research program currently underway at ORD’s Ground Water and Ecosystems Restoration Division (GWERD) to evaluate CAFO impacts on ground water quality. The overall research objectives are to characterize the potential for gro...