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Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson Jan 1992

Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to speed the process of computing long term groundwater pumping strategies. These combined models can also greatly ease the planning tasks of water management agencies. They make the process of computing optimal perennial yield groundwater management strategies fairly straightforward. S/0 models dramatically improve conjunctive water management and can help minimize the cost of groundwater contaminant clean-up. The differences between S/0 models and the simulation (S) models currently used by over 98 % of practitioners are illustrated with recent applications of S/0 models in regional planning.


Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta Jan 1992

Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Generally, the embedding technique for optimizing groundwater management has been limited to small scale or steady-state groundwater flow management cases. The embedding approach causes sparse, highly structured constraint matrices which have been sometimes difficult to solve. Embedding applications have been limited by lack of: optimization algorithms able to easily address such matrices for large scale problems, and efficient methods for addressing common nonlinearities and converging to a solution. Computer software, USUEM, addresses these issues by: creation of alternative linear, nonlinear, combined and partitioned formulations of the same problem, implemention of an efficient cycling procedure, and good selection of optimization algorithm …


Bioengineering For Water Cleanup: State-Of-The-Art Assessment, Judith L. Sims, Ronald C. Sims, Jon S. Ginn Jan 1992

Bioengineering For Water Cleanup: State-Of-The-Art Assessment, Judith L. Sims, Ronald C. Sims, Jon S. Ginn

Reports

No abstract provided.


Evaluation Of Mechanisms Of Alteration And Humification Of Pahs For Water Quality Management, Ronald C. Sims, Carolyn K. Abbott Jan 1992

Evaluation Of Mechanisms Of Alteration And Humification Of Pahs For Water Quality Management, Ronald C. Sims, Carolyn K. Abbott

Reports

Introduction: Creosote-pentachlorophenol (PCP) is a mixture commonly used as a wood preservative in the U.S. (1). A 1988 survey (2) indicated that 1,397 wood preserving waste contaminated sites exist in the United States consisting of 555 active wood treatment plants and 842 inactive plants. Stinson (3) indentifed 58 wood preserving sites on the National Priorities List, of which 51 have PCP and/or creosote or polycyclic aromatic hydrocarbon (PAH) contamination. Principal classes of organic constituents present in creosote waste are PAHs (~85% by weight) and phenolics. PAHs with less than three fused benzene rings comprise 69% (i.e., naphthalene, anthracene and phenanthrene); …


Composting Of Explosives Contaminated Soil Using The White Rot Fungus Phanerochaete Chrysosporium, Michael J. Mcfarland, Shashi Kalaskar, Eric Baiden Jan 1992

Composting Of Explosives Contaminated Soil Using The White Rot Fungus Phanerochaete Chrysosporium, Michael J. Mcfarland, Shashi Kalaskar, Eric Baiden

Reports

Bioaugmentation using the white rot fungus Phanerochaete chrysosporium was found to be effective in enhancing TNT removal in lightly (i.e., below 100 mg/kg) contaminated soil. The percent reduction in TNT increased from 15% to 53% when soils were treated with fungal inoculated organic material. Maximum removal rates improved from 0.33 mg TNT/kg-day to 0.76 mg TNT/kg-day during the same treatment. Neither fungal inoculation nor organic amendment addition resulted in improving TNT removal kinetics in highly contaminated soils (i.e., above 1000 mg/kg). Executive Summary: Laboratory scale compost studies were conducted to evaluate the effect of bioaugmentation with the white rot fungus,


A Spatially Distributed Water Balance Based On Physical, Isotropic And Airborne Remotely Sensed Data, C. M.U. Neale, David G. Tarboton, J. J. Mcdonnell Jan 1992

A Spatially Distributed Water Balance Based On Physical, Isotropic And Airborne Remotely Sensed Data, C. M.U. Neale, David G. Tarboton, J. J. Mcdonnell

Reports

Introduction: The objective of this research to develop a spatially distributed water balance model based on the integration of spatially distributed data. Progress this year has consisted of model development, instrument acquisition, installation and development of experimental procedures, and baseline data collection. The original research plan called for detailed observations related to the water balance over the year September 1991 to August 1992. The detailed measurements were to start with accumulation of the snowpack followed by melt and evapotranspiration measurements from March to August. The objective was to measure the energy balance parameters starting with the peak accumulation, through the …


Soil Nitrogen Dynamics Following Harvesting And Conversion Of Red Alder And Douglas-Fir Stands, H. Van Miegroet, P. S. Homann, D. W. Cole Jan 1992

Soil Nitrogen Dynamics Following Harvesting And Conversion Of Red Alder And Douglas-Fir Stands, H. Van Miegroet, P. S. Homann, D. W. Cole

Watershed Sciences Faculty Publications

Drastic reductions in NO3- leaching have been observed after harvesting of mature red alder (Alnus rubra Bong.) stands. Our objective was to examine whether these reduction were linked to changes in soil N dynamics. Adjacent alder and Douglas fir [Pseudotsuga menziessii (Mirbel.) Franco] stands on young glacial soils (Alderwood; a loamy-skeletal, mixed, mesic, ortstein Aquic Haplorthod) in western Washington were harvested and replanted with either alder or Douglas fir seedlings; reference plots were established in nearby undisturbed stands. Three years after site conversion, when NO3- leaching declined most drastically in the harvested alder plots, net N mineralization and net nitrification …


Estimation Of Shrub Leaf Biomass Available To White-Tailed Deer, Lynn Rogers, Ronald E. Mcroberts Jan 1992

Estimation Of Shrub Leaf Biomass Available To White-Tailed Deer, Lynn Rogers, Ronald E. Mcroberts

Aspen Bibliography

No abstract provided.


Introduction To The Variational Bicomplex, Ian M. Anderson Jan 1992

Introduction To The Variational Bicomplex, Ian M. Anderson

Mathematics and Statistics Faculty Publications

The variational bicomplex was first introduced in the mid 1970's as a means of studying the inverse problem of the calculus of variations. This is the problem of characterizing those differential equations which are the Euler-Lagrange equations for a classical, unconstrained variational problem. Since then, the variational bicomplex has emerged as an effective means for studying other formal, differential-geometric aspects of the calculus of variations. Moreover, it has been shown that the basic variational bicomplex constructed to solve the inverse problem can be modified in various ways and that the cohomology groups associated with these modified bicomplexes are relevant to …


Calculation Of Barriers To Proton Transfer Using Multiconfiguration Self‐Consistent‐Field Methods. I. Effects Of Localization, K. Luth, Steve Scheiner Jan 1992

Calculation Of Barriers To Proton Transfer Using Multiconfiguration Self‐Consistent‐Field Methods. I. Effects Of Localization, K. Luth, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The usefulness of multiconfiguration self‐consistent‐field (MCSCF) calculations in computing correlated proton transfer potentials is investigated for the systems HF2−, H7N2+, H3O2−, and H5O2+. In deciding whether to include particular molecular orbitals, it is important to consider the balance of electron density between the donor and acceptor groups and the interactions that are incorporated in the orbitals. Only orbitals which have the proper symmetry to interact with the transferring hydrogen need be included in the MCSCF active space. Reasonable transfer barriers are obtained …


Proton–Donor Properties Of Water And Ammonia In Van Der Waals Complexes With Rare‐Gas Atoms. Kr–H2o And Kr–Nh3, G. Chalasinski, M. M. Szczesniak, Steve Scheiner Jan 1992

Proton–Donor Properties Of Water And Ammonia In Van Der Waals Complexes With Rare‐Gas Atoms. Kr–H2o And Kr–Nh3, G. Chalasinski, M. M. Szczesniak, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The perturbation theory of intermolecular forces in conjunction with the supermolecular Møller–Plesset perturbation theory is applied to the analysis of the potential‐energy surfaces of Kr–H2O and Kr–NH3 complexes. The valleylike minimum region on the potential‐energy surface of Kr–H2O ranges from the coplanar geometry with the C2 axis of H2O nearly perpendicular to the O–Kr axis (T structure) to the H‐bond structure in which Kr faces the H atom of H2O. Compared to the previously studied Ar–H2O [J. Chem. Phys. 94, 2807 (1991)] the minimum has more …


General Catalog 1992 - 1994, Utah State University Jan 1992

General Catalog 1992 - 1994, Utah State University

University Catalogs

Contains course descriptions, University college calendar, and college administration.


Nonparametric Stratigraphic Interpretation From Drill Log Data, Upmanu Lall, A. I. Ali Jan 1992

Nonparametric Stratigraphic Interpretation From Drill Log Data, Upmanu Lall, A. I. Ali

Reports

Near surface groundwater contamination is a widespread problem. The potential for contamination of deep aquifers in such areas depends on the vertical hydraulic gradient as well as the extent and location of interconnection between the upper and lower aquifers. In alluvial, sedimentary environment, the geologic units are typically weakly connected lenses or layers of high or low conductivity with variable size, geometry and orientation. Drill logs provide qualitative, local information on such aquifer heterogeneities. A binary (high or low conductivity) indicator function is used to describe the aquifer system. A nonparametric statistical methodology for assessing the probability that a particular …


Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta Jan 1992

Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

In 1988 a preliminary assessment (PA) study was conducted at Chemical Disposal Pit No. 4 to address several concerns of Hill Air Force Base (HAFB), the facility operators. The objectives of the PA were; i) to assess the potential for organic chemical releases to the subsurface environment, and ii) to determine the need for any immediate control measures, if the subsurface environment were threatened.


Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta Jan 1992

Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

No abstract provided.


The Feasibility Of Enhacing Streamflow In The Sevier River Basin Of Utah By Seeding Winter Mountain Clouds, Arlin B. Super, David W. Reynolds, Bureau Of Reclamation, U.S. Department Of The Interior Dec 1991

The Feasibility Of Enhacing Streamflow In The Sevier River Basin Of Utah By Seeding Winter Mountain Clouds, Arlin B. Super, David W. Reynolds, Bureau Of Reclamation, U.S. Department Of The Interior

All U.S. Government Documents (Utah Regional Depository)

The Bureau of Reclamation conducted a feasibility study of seeding winter mountain clouds as a possible means of enhancing the water supplies of the Sevier River Basin of Utah. A considerable body of pertinent meteorological observations from in or near the basin is examined. The evidence indicates that Utah winter mountain clouds often have more supercooled liquid water available than is naturally converted to snowfall. Thus, the needed "raw material" for cloud seeding to be effective is frequently available. Much of the excess liquid water has been found in the lowest kilometer or less over the mountain barriers, a region …


Surface Topographical And Compositional Characterization Using Backscattered Electron Methods, Dirk A. Wassink, Jerry Z. Raski, Joel A. Levitt, David Hildreth, Kenneth C. Ludema Oct 1991

Surface Topographical And Compositional Characterization Using Backscattered Electron Methods, Dirk A. Wassink, Jerry Z. Raski, Joel A. Levitt, David Hildreth, Kenneth C. Ludema

Scanning Microscopy

Two pairs of diametrically opposed Schottky surface barrier diodes in a modified scanning electron microscope (SEM) are used to reconstruct surface elevations and composition differences. An empirically determined function of difference of signals from opposing diodes is used to calculate slopes, which are then integrated to elevations by an efficient 2-dimensional Fast Fourier Transform. Composition differences are distinguished by variations in the overall backscattered electron (BSE) intensity estimated by the sum of the four diode signals. Arithmetic average roughness measurements from the BSE device are within 10% of stylus surface tracer measurements when surface slopes average less than 6 degrees …


Electron Beam Induced Current Investigations Of Electrical Inhomogeneities With High Spatial Resolution, Eu. Yakimov Oct 1991

Electron Beam Induced Current Investigations Of Electrical Inhomogeneities With High Spatial Resolution, Eu. Yakimov

Scanning Microscopy

Electron beam induced current (EBIC) microscopy is a very promising SEM technique for the study of diffusion length and depletion region width inhomogeneities with high spatial resolution. However, this resolution is limited by the dimensions of the electron-hole pair generation region. In this paper the possibilities to improve spatial resolution are discussed. Electron beam tomography, i.e. the reconstruction of physical property distributions from sets of two-dimensional images, seems to be the most promising for this purpose. It is shown that in the case of dislocations it is possible to obtain information about dislocation impurity atmosphere parameters from EBIC measurements. The …


Microphotometric Quantification Of Crystal Growth In Gels For The Study Of Calcium Oxalate Urolithiasis, Wolfgang Achilles Oct 1991

Microphotometric Quantification Of Crystal Growth In Gels For The Study Of Calcium Oxalate Urolithiasis, Wolfgang Achilles

Scanning Microscopy

This paper gives a review on an efficient microtechnique (Gel Crystallization Method; GCM) which quantifies crystal growth in gel matrices, and its application to research into urinary stone formation. Relative crystal growth rates (Vcr) of calcium oxalate hydrates (CaOx) were determined by simultaneous multiple measurements in 96-well microplates using computer controlled microscopic photometry. Efficiency: 120 kinetic measurements/h; imprecision: < 2% at standard conditions. The method was applied to study the effects of diverse small-ionic and macromolecular constituents of human urine on the crystal growth rate of CaOx. The 'inhibitory activity' of urine could be evaluated by comparison of the Vcr measured in native and corresponding artificial samples. Macromolecules, at physiological concentration, played only a minor role as inhibitors in the model under regard. The GCM was employed to study the in-vivo effects of different therapeutic measures on CaOx growth in urine of normal volunteers. While the application of alkali citrate resulted in a > 70% decline of Vcr, no beneficial effects could be found with three magnesium compounds, and a dietary fiber preparation. In a study including 20 male recurrent CaOx stone formers and 29 well-matched controls, among all parameters under investigation, the Vcr showed the …


Restoration And Expansion Of Bear River Migratory Bird Refuge, Brigham City, Utah, Environmental Assessment, Keith S. Hansen, U.S. Fish And Wildlife Service, Division Of Refuges And Wildlife Oct 1991

Restoration And Expansion Of Bear River Migratory Bird Refuge, Brigham City, Utah, Environmental Assessment, Keith S. Hansen, U.S. Fish And Wildlife Service, Division Of Refuges And Wildlife

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.


Auxiliary Field In Conformal Gauge Theory, James Thomas Wheeler Sep 1991

Auxiliary Field In Conformal Gauge Theory, James Thomas Wheeler

All Physics Faculty Publications

When the full conformal algebra is gauged there arises a gauge field for inverse translations in addition to the usual translational gauge field. By considering every scale-invariant action constructible from the curvatures of the conformal group and the metric, we show that when the gauge field of the usual translations is identified as the vierbein, the gauge field of inverse translations may always be eliminated by its own field equation. After this elimination, every torsion-free, scale-invariant action reduces to a linear combination of the square of the conformal curvature tensor Cαβμν and the square of the Weyl field strength …


Initial Climate Change Scenario For The Western United States, United States Department Of The Interior, Bureau Of Reclamation Sep 1991

Initial Climate Change Scenario For The Western United States, United States Department Of The Interior, Bureau Of Reclamation

Meterology

Observations of atmospheric carbon dioxide (CO2) concentrations in recent decades have shown an accelerating upward trend due mainly to burning of fossil fuels. Physical considerations indicate that observed and projected increases in the concentrations of CO2 and other greenhouse gases in the atmosphere will lead to significant global warming. Previous authors have followed both empirical and theoretical approaches to develop scenarios for changed climate conditions. The most common empirical approach is the use of analogs of global warming drawn from historical records and paleoclimates. The principal theoretical approach involves the interpretation of output for general circulation models …


Preparation And Characterization Of Some Particulate Materials In The Aluminum Industry, A. Csordás-Tóth, B. Szikora, J. Kürthy-Komlósy, I. Tassy Sep 1991

Preparation And Characterization Of Some Particulate Materials In The Aluminum Industry, A. Csordás-Tóth, B. Szikora, J. Kürthy-Komlósy, I. Tassy

Scanning Microscopy

Preparation and characterization techniques for the following particulate materials are reviewed: micromineralogical samples of bauxite, alumina and its trihydroxide, as well as sedimentary and respirable particles. Scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDS) and image analysis were used to characterize the microminerals of bauxite. Comparisons were made among micromineralogical samples with various grain size fractions and the degree of weathering could be quantified. Programs were developed for characterization of the sandy and floury types of aluminum trihydroxide and alumina. We have used backscattered electron SEM images to characterize the size and shape of various aluminum trihydroxides. Comparison could …


Single Event Upset Error Protection For Solid State Data Memory On Microsatellites, M.S. Hodgart, C.I. Underwood, J.W. Ward Aug 1991

Single Event Upset Error Protection For Solid State Data Memory On Microsatellites, M.S. Hodgart, C.I. Underwood, J.W. Ward

Small Satellite Conference

Many microsatellite missions rely upon large arrays of CMOS static RAM for data storage. Even a satellite with strict power and volume limitations can carry several Mbytes of SRAM. Experience has shown that these memory arrays are useful for scientific data collection image storage, store and- forward message switching and spacecraft telemetry monitoring. This paper describes the authors' design and implementation of error protection codes which protect large CMOS RAM arrays from radiation-induced single event upsets.


Brem-Sat Attitude Control At Low Altitudes, Hans Koenigsmann, H. Rath, H. Oelze, A. Ginatii Aug 1991

Brem-Sat Attitude Control At Low Altitudes, Hans Koenigsmann, H. Rath, H. Oelze, A. Ginatii

Small Satellite Conference

The German University satellite BREM-SAT (scheduled for launch in early 1993) carries two experiments which require attitude control down to 150 km altitude and aerodynamic stabilization between 150 and 100 km altitude. These contradicting requirements and new ways to change the satellite's attitude and to keep it stable and controlled at very high disturbance torque levels. Complex numerical attitude simulation has shown the feasibility to maintain the required attitude with a momentum wheel and a single torque coil down to 150 km when optimized algorithms are used. To achieve the aerodynamic stabilization, the momentum wheel has to be ejected and …


"Space Eggs" - Satellite Coverage Model For Low Earth Orbit Constellations, Janis Indrikis, Robert Cleave Aug 1991

"Space Eggs" - Satellite Coverage Model For Low Earth Orbit Constellations, Janis Indrikis, Robert Cleave

Small Satellite Conference

The effectiveness calculations of global, regional, and area coverage for proliferated small satellite constellations in low altitude orbits stress the capability of conventional analytical techniques. A new approach that combines the Mollweide (equal area) projection with an on-screen color manipulation of the picture elements (or pixels) has been developed and utilized over the past decade. This technique enables the optimization of large satellite constellations with multiple communication or sensor viewing configurations, with a minimum number of calculations. Complex viewing geometries are well adapted with this analytical approach, along with exclusion requirements such as the sun, moon or earth avoidance. This …


Medsat: A Small Satellite For Malaria Early Warning And Control, James Slawski, John Vesecky, Byron Wood, James Lawless Aug 1991

Medsat: A Small Satellite For Malaria Early Warning And Control, James Slawski, John Vesecky, Byron Wood, James Lawless

Small Satellite Conference

This paper presents the design for a low cost, light satellite used to aid in the control of vector-borne diseases like malaria. The 340 kg satellite contains both a synthetic aperture radar and a visual/infrared multispectral scanner for remotely sensing the region of interest. Most of the design incorporates well established technology, but innovative features include the Pegasus launch vehicle, low mass and volume SAR and VIS/IR sensors, integrated design, low power SAR operation, microprocessor power system control, and advanced data compression and storage. This paper describes the main design considerations of the project which include, the remote sensing task, …


To The Moon From A B-52: Robotic Lunar Exploration Using The Pegasus Winged Rocket And Ballistic Lunar Capture, Edward Belbruno, Rex Ridenoure, Jaime Fernandez Aug 1991

To The Moon From A B-52: Robotic Lunar Exploration Using The Pegasus Winged Rocket And Ballistic Lunar Capture, Edward Belbruno, Rex Ridenoure, Jaime Fernandez

Small Satellite Conference

A subset of the presently-defined NASA robotic lunar exploration objectives may be achievable with a new mission architecture involving the Pegasus winged rocket, small satellites, and a new class of Earth-Moon trajectories incorporating ballistic lunar capture. Enabling this potentially low-cost method of lunar exploration - perhaps for a few tens of millions of dollars per mission - is the application of the Weak Stability Boundary Theory developed by Belbruno during 1987-89, which leads to ballistic ("maneuverless") Earth-Moon trajectories. On such a path, a spacecraft could be orbited at the Moon for little additional ∆ V (< 50 m/s for minor trajectory correction maneuvers) beyond that supplied by the Pegasus for the initial Earth departure burn, resulting in a significant propellant savings. (Additional maneuvers would then be required to establish a more useful lunar orbit.) The price for this savings is an extended trip time to the Moon of 3-5 months. This type of trajectory is presently being demonstrated for the first time by the Japanese Hiten spacecraft, using an …


Elemental Analysis And Fine Structure Of Mitochondrial Granules In Growth Plate Chondrocytes Studied By Electron Energy Loss Spectroscopy And Energy Dispersive X-Ray Microanalysis, Joanna Wroblewski, Romuald Wróblewski, Claudie Mory, Christian Colliex Aug 1991

Elemental Analysis And Fine Structure Of Mitochondrial Granules In Growth Plate Chondrocytes Studied By Electron Energy Loss Spectroscopy And Energy Dispersive X-Ray Microanalysis, Joanna Wroblewski, Romuald Wróblewski, Claudie Mory, Christian Colliex

Scanning Microscopy

Electron energy loss spectrometry - EELS, and energy dispersive X-ray microanalysis - XRMA, were used to study the elemental composition of mitochondrial dense granules - mdg. The study was performed on dry cut thin sections (80-200 nm) of freeze-dried and low temperature embedded cartilage. Results obtained by means of XRMA clearly showed high phosphorus and calcium content in the mdg. Using EELS at 100 kV primary voltage we found that small concentrations of elements (i.e. below typically 1% atomic weight) are difficult to analyze and map, this especially in sections thicker than 50-60 nm. Surprisingly, analysis of calcium can be …


Comparing Simulated And Experimental Hysteretic Two-Phase Transient Fluid Flow Phenomena, R. J. Lenhard, J. C. Parker, Jagath J. Kaluarachchi Aug 1991

Comparing Simulated And Experimental Hysteretic Two-Phase Transient Fluid Flow Phenomena, R. J. Lenhard, J. C. Parker, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A hysteretic model for two-phase permeability (k)-saturation (S)-pressure (P) relations is outlined that accounts for effects of nonwetting fluid entrapment. The model can be employed in unsaturated fluid flow computer codes to predict temporal and spatial fluid distributions. Consideration is given to hysteresis in S-P relations caused by contact angle, irregular pore geometry, and nonwetting fluid entrapment effects and to hysteresis in k-Srelations caused by nonwetting fluid entrapment effects. An air-water flow experiment is conducted with a 72-cm vertical soil column where the water table is fluctuated to generate scanning S-P paths. Water contents are measured via a gamma radiation …