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Articles 4711 - 4740 of 5443
Full-Text Articles in Engineering
Optimal Conjunctive Use Of Ground And Surface Waters, Richard C. Peralta, A. Gharbi, L. S. Willardson, A. W. Peralta
Optimal Conjunctive Use Of Ground And Surface Waters, Richard C. Peralta, A. Gharbi, L. S. Willardson, A. W. Peralta
Civil and Environmental Engineering Faculty Publications
Conjunctive water management involves coordinating the use of groundwater and surface water in time and in space. The water sources might or might not be in hydraulic connection with each other. In this chapter, conjunctive water use involves the combined use of surface and groundwater to supply crop water needs.
Two simplified examples of conjunctive use follow. Farmer Allen uses river water to irrigate his crops. In dry years, with below average stream flow, his surface water supply is severely limited by late summer. To augment this surface water supply, he pumps groundwater. In wet years, when the surface water …
Conjunctive Water Use/Sustained Groundwater Yield Planning: Case History, A. R. Yar, Richard C. Peralta
Conjunctive Water Use/Sustained Groundwater Yield Planning: Case History, A. R. Yar, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
A methodology for computing perennial ground-water yield and conjunctive water use strategies is presented, using the Arkansas Grand Prairie as a case study. This includes development and use of an optimization model for computing sustainable ground-water pumping strategies and a post-processor for allocating ground-water and surface water supplies in time and space. The optimization model utilizes embedded finite difference flow equations as constraints and bounds on pumping, recharge and potentiometric head. Computed conjunctive use strategies will maintain, as much as possible, the existing stressed potentiometric surface. They will also assure at least 6 meters of saturated thickness in all locations …
Thiokol/Wasatch Installation Evaluation Of The Redesigned Field Joint Protection System (Concepts 1 And 3) Final Test Report, United States, National Aeronautics And Space Administration
Thiokol/Wasatch Installation Evaluation Of The Redesigned Field Joint Protection System (Concepts 1 And 3) Final Test Report, United States, National Aeronautics And Space Administration
Miscellaney
Redesigned field joint protection system installations were performed between 7 and 15 Nov 1989 at the Thiokol Corporation Static Test Bay T-18. The purpose of the installations was to develop procedures for two field joint protection system redesign concepts (Concepts 1 and 3), and to evaluate the processing capability of each concept. The Concept 1 (Double Cork Band Design) configuration consists of two cork bands with K5NA ablation compound applied between them and to the bottom edge of the aft cork band. The Concept 3 (K5NA Design) configuration consists of a single layer of K5NA over the joint/heater/sensor/pin retainer band …
Pesticide Movement And Water Management, Majid Ehteshami, Richard C. Peralta
Pesticide Movement And Water Management, Majid Ehteshami, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Agricultural chemicals are essential components of agricultural production systems in the United states. Pesticides control weeds, insects, and have had an important role in increasing agricultural productivity in the last 50 years, despite diminishing crop land acreage. The benefits of chemicals use options in agriculture must be balanced against potential contamination of surface water and ground water resources. This study shows the effect of water management practices on pesticide movement and its potential pollution to ground water. It indicates that careful use of pesticides, water management practices and irrigation system design alternatives could cause a major reduction in ground water …
Water Resources Development Alternatives For The Mississippi Alluvial Plain In Eastern Arkansas, Gary L. Mahon, John E. Terry, Richard C. Peralta
Water Resources Development Alternatives For The Mississippi Alluvial Plain In Eastern Arkansas, Gary L. Mahon, John E. Terry, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Effective management of the water resources of the Mississippi Alluvial Plain in eastern Arkansas involves understanding the nature of existing problems, estimating total water demands, predicting how much of the total demand can be provided by the underlying aquifer and available surface-water sources, and deducing how much water must come from alternate sources. Various Federal and State agencies have cooperatively provided hydrologic information for the area to evaluate water-resources development alternatives ensuring that (1) the use of water from the aquifer be maximized while maintaining a minimum of 20 feet of saturated thickness, (2) the use of surface water be …
Expandable Membrane Ground Anchors In Talus, United States Department Of Transportation, Federal Highway Administration
Expandable Membrane Ground Anchors In Talus, United States Department Of Transportation, Federal Highway Administration
Dams
Expander Body (EB) tieback anchors were installed in talus material in Glenwood Canyon and evaluated as to their ease of installation and performance. The EB consists of a steel tube with thin, folded walls which is expanded in the soil by injection of cement grout. The EB system can be expanded in coarse, angular materials at high pressure without rupturing. It, therefore, can be successfully used to limit grout take in permeable materials.
Based on the results of this study, the EB system was approved as a permanent anchoring method in construction of I 70 through Glenwood Canyon.
Application Of Bmp For Prevention Of Ground-Water Contamination, Majid Ehteshami, Richard C. Peralta
Application Of Bmp For Prevention Of Ground-Water Contamination, Majid Ehteshami, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
The use of pesticides is an integral part of today's agriculture. In many cases, pesticides safeguard crops from severe pest infestation, or increase yield by suppressing competing weed growth. Pesticides often make the difference between profits and losses in farming operations. However, pesticides, even in extremely low concentrations, can pose a risk to human health and to the environment. Applied to plant or soil surfaces, or injected into the soil, pesticides may leach to the ground water or may be washed off with surface water. Pesticide contaminated surface water can reach ground water, or contaminated ground water can reach the …
Bioremediation Of Contaminated Surface Soils, J. L. Sims, R. C. Sims, J. E. Matthews
Bioremediation Of Contaminated Surface Soils, J. L. Sims, R. C. Sims, J. E. Matthews
Reports
Biological remediation of soils contaminated with organic chemicals is an alternative treatment technology that can often meet the goal of achieving a permanent clean-up remedy at hazardous waste sites, as encouraged by the U.S. Environmental Protection Agency (U.S. EPA) for implementation of The Superfund Amendments and Authorization Act (SARA) of 1986. Bioremediation is consistent with the philosophical thrust of SARA, for it involves the use of naturally occurring microorganisms to degrade and/or detoxify hazardous constituents in the soil at a contaminated slip to protect public health and the environment.Bioremediation of contaminated soils, including applications and limitations, has been addressed.
On-Farm Reservoir Construction In The Grand Prairie Region Of Arkansas: An Engineering Economic Analysis, Jayson K. Harper, Richard C. Peralta, Robert N. Shulstad
On-Farm Reservoir Construction In The Grand Prairie Region Of Arkansas: An Engineering Economic Analysis, Jayson K. Harper, Richard C. Peralta, Robert N. Shulstad
Civil and Environmental Engineering Faculty Publications
No abstract provided.
An Evaluation Of The Plasma Frequency Probe, Charles Merrill Swenson
An Evaluation Of The Plasma Frequency Probe, Charles Merrill Swenson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Electron density in a plasma can be measured by determining the plasma frequency. For 20 years this electron density measurement technique has been used with the plasma frequency probe. The purpose of this paper is to characterize, evaluate, and suggest improvements for this instrument. Although the current plasma frequency probe is a highly successful instrument for measuring absolute electron density in the ionosphere, several areas for improvement were found. These were in the radio frequency head and the voltage controlled oscillator. Currently, the plasma frequency probe is approximately 20% accurate in determining absolute densities around 1.5x104 electrons/cm3 but …
Density-Dependent Convective Flow In Closed Basins, Kim L. Mccleary
Density-Dependent Convective Flow In Closed Basins, Kim L. Mccleary
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Great Basin is a region of the Basin and Range Physiographic Province, which is completely isolated hydrologically from the sea. All precipitation that falls within the Great Basin is lost from the land surface or from the surface of closed inland lakes through evapotranspiration. Playas are often found at the base of these undrained basins. This study focuses on subsurface groundwater flow patterns in closed basins. Because all discharge from the basins occurs via evapotranspiration on and near the playa, the water table of the aquifer beneath the playa is often just below the ground surface. Fluctuations of the …
Agricultural Pesticide Hazard To Groundwater In Utah, Hubert Eisele, Majid Ehteshami, Richard C. Peralta, Howard M. Deer, Terry T. Tindall
Agricultural Pesticide Hazard To Groundwater In Utah, Hubert Eisele, Majid Ehteshami, Richard C. Peralta, Howard M. Deer, Terry T. Tindall
Civil and Environmental Engineering Faculty Publications
We gratefully acknowledge the funding support of the Utah Department of Agriculture and the following offices at Utah State University. The Department of Agricultural and Irrigation Engineering, the International Irrigation Center, the Department of Animal, Dairy and Veterinary Sciences, the Department of Soil Science and Biometerology, and the University Extension Services.
Computational Aspects Of Chance-Constrained Sustained Groundwater Yield Management, R. R.A. Cantiller, Richard C. Peralta
Computational Aspects Of Chance-Constrained Sustained Groundwater Yield Management, R. R.A. Cantiller, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
A methodology for including chance-constraints in models for maximizing regional sustained-yield groundwater extraction is presented. The procedure utilizes the spatially distributed mean and variance of saturated thickness in a confined aquifer. This data is derivable from kriging, a geostatistical technique. The technique is applied to a scenario of somewhat egalitarian agricultural development dependent on groundwater. Decision makers in this situation know that groundwater availability is insufficient to supply all potential demand. They plan to implement a sustained yield groundwater extraction strategy. They know that because of uncertain knowledge of aquifer parameters, at some point in the future, available groundwater in …
Symmetric Self-Electro-Optic Effect Device: Optical Set-Reset Latch, Differential Logic Gate, And Differential Modulator/Detector, Anthony L. Lentine, Harvard S. Hinton, David A. B. Miller, Jill E. Henry, J. E. Cunningham, Leo M. F. Chirovsky
Symmetric Self-Electro-Optic Effect Device: Optical Set-Reset Latch, Differential Logic Gate, And Differential Modulator/Detector, Anthony L. Lentine, Harvard S. Hinton, David A. B. Miller, Jill E. Henry, J. E. Cunningham, Leo M. F. Chirovsky
Electrical and Computer Engineering Faculty Publications
The symmetric self-electrooptic-effect device (S-SEED), a structure consisting of two p-i-n diodes electrically connected in series and acting as an optically bistable set-reset latch, is discussed. Applications and extensions of this device are also discussed. The devices do not require the critical biasing that is common to most optically bistable devices and thus is more useful for system applications. They have been optically cascaded in a photonic ring counter and have been used to perform different NOR, OR, NAND, and AND logic functions. Using the same device, a differential modulator that generates a set of complementary output beams with a …
Toxicity And Environmental Health Hazards Of Petroleum Products In Wells Used For Drinking Water In The Intermountain West, Robert D.R. Parker, Raghubir P. Sharma, R. Ryan Dupont, Gin-Chang Hsieh
Toxicity And Environmental Health Hazards Of Petroleum Products In Wells Used For Drinking Water In The Intermountain West, Robert D.R. Parker, Raghubir P. Sharma, R. Ryan Dupont, Gin-Chang Hsieh
Reports
Introduction: Groundwater is aprimary source of drinking water for about 50 percent of the population in the U.S. This source of drinking water has been generally regarded as safe from contamination. Several papers indicate that numerous underground storage tanks containing petroleum products may be leaking and contaminating public water supply wells across the U.S. (Matis, 1971; Ferguson, 1979; Woodhull, 1981; Burmaster and Harris, 1982; Lehman, 1984; Dowd, 1984; OTA, 1984). A study conducted by the Utah Cureau of Solid and Hazardous Wastes in 1985 concluded that there are at least 2,314 underground steel tanks, most of which are used to …
Soil Phase Photodegradation Of Toxic Organics At Contaminated Disposal Sites For Soil Renovation And Groundwater Quality Protection, W. M. Moore, R. Ryan Dupont, J. E. Mclean
Soil Phase Photodegradation Of Toxic Organics At Contaminated Disposal Sites For Soil Renovation And Groundwater Quality Protection, W. M. Moore, R. Ryan Dupont, J. E. Mclean
Reports
Accurate assessment of the potential for contaminated soil remediation requires detailed knowledge of the fate of waste constituents within the soil environment. For many non-biodegradable organics compounds, photochemical degradation may provide a potential pathway for the removal of such compounds from soil surfaces. A study was conducted to evaluate the rate of photodegradation of ten hazardous organic compounds from three soils, silica gel, and four soil minerals (kaolinite, montmorillonite, illite, and calcite) under conditions of controlled irradiation. In addition, the effect of siz amendment treatments (methylene blue, riboflavin, hydrogen peroxide, diethylamine, peat moss, and silica gel) on the rates of …
Evaluation Of Algrow As A Binder In Hydromulch And Preliminary Determination Of The Influence Of Algrow On Germination And Seedling Growth, C. Earl Israelsen, Gilberto Urroz, Ronald V. Canfield
Evaluation Of Algrow As A Binder In Hydromulch And Preliminary Determination Of The Influence Of Algrow On Germination And Seedling Growth, C. Earl Israelsen, Gilberto Urroz, Ronald V. Canfield
Reports
Introduction: The application of mulch during or immediately following seeding provides the minimum following advantages: energy dissipation of falling raindrops which decreases or eliminates erosion, prevention of surface-soil crusting, decreased water loss, and surface temperature modification. To better hold mulch in place, chemical binders are addd to it during munufacture or just before it is applied to the soil. Sometimes a binder is applied as an oversptray after the mulch is in place. (This overspray is generally referred to as a tackifier.) Algea Produkter A/S, Drammen, Norway, produces a product called ALGROW which may habe utility as a mulch binder …
Friction Factor Tests On 375 Mm High Density Polyethylene Pipe, Steven L. Barfuss, J. Paul Tullis
Friction Factor Tests On 375 Mm High Density Polyethylene Pipe, Steven L. Barfuss, J. Paul Tullis
Reports
No abstract provided.
Bear River Water Quality: Bioavailable Phosphorus Measurement, Sources, And Control, Kenneth W. Barker, Darwin L. Sorensen, Jay C. Andersen, Jean M. Ihnat
Bear River Water Quality: Bioavailable Phosphorus Measurement, Sources, And Control, Kenneth W. Barker, Darwin L. Sorensen, Jay C. Andersen, Jean M. Ihnat
Reports
No abstract provided.
Friction Factor Tests On 300 Mm High Density Polyethylene Pipe, Steven L. Barfuss, J. Paul Tullis
Friction Factor Tests On 300 Mm High Density Polyethylene Pipe, Steven L. Barfuss, J. Paul Tullis
Reports
No abstract provided.
Coordinating Institutional Approaches To Assure Sustainable Groundwater Of Adequate Quality And Quantity In Utah, Richard C. Peralta, A. W. Peralta, K. Wyatt, Robert W. Hill
Coordinating Institutional Approaches To Assure Sustainable Groundwater Of Adequate Quality And Quantity In Utah, Richard C. Peralta, A. W. Peralta, K. Wyatt, Robert W. Hill
Civil and Environmental Engineering Faculty Publications
Utah is an arid state, without the abundant surface water resources enjoyed by states in the humid east. Most precipitation in the state falls in the higher elevations of the Uinta and Wasatch mountains of northern and central Utah. Much of this precipitation ultimately ends up in alluvial deposits at the base of these ranges, from which the vast majority of pumping wells draw their water (Barnes and Croft, 1986). This groundwater is an essential resource for use by the people of Utah. About sixty-three percent of Utah's population is at least partially reliant on groundwater for domestic use. In …
Optimizing Short-Term Plume Containment: Comparison Of Well Arrangements., Herminio H. Suguino, Richard C. Peralta
Optimizing Short-Term Plume Containment: Comparison Of Well Arrangements., Herminio H. Suguino, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Three well configurations were compared in terms of term ground-water contaminant plume containment. include parallel, octagonal and combination systems. system had three extraction wells upqradient and injection wells downgradient of the contaminant plume.
For each system, optimal pumping values and resulting potentiometric surface smoothness were computed for a hypothetical plume. Tested models utilized linear programming optimization and simulation via the response matrix method.
The octagonal well configuration required less pumping for a pumping period of 8 days, than did the parallel or combination systems. The octagonal configuration resulted in the smoothest potentiometric surface, in terms of difference in final head …
Sstar Users Manual, Richard C. Peralta, P. W. Killian, A. Yazdanian, V. Kumar
Sstar Users Manual, Richard C. Peralta, P. W. Killian, A. Yazdanian, V. Kumar
Civil and Environmental Engineering Faculty Publications
There are four objective functions available to date (11/86), these include 1) maximimize total regional groundwater withdrawl. 2) minimize total coat of satisfying regional needs. and 3) maximize the sum of selected local withdrawls. and 4) maximize the present value of total net economic return.
Finite Element Model Of Nitrogen Species Transformation And Transport In The Unsaturated Zone, Jagath J. Kaluarachchi, J. C. Parker
Finite Element Model Of Nitrogen Species Transformation And Transport In The Unsaturated Zone, Jagath J. Kaluarachchi, J. C. Parker
Civil and Environmental Engineering Faculty Publications
A two-dimensional finite element model based on Galerkin's weighted residual approach and incorporating an upstream weighting technique was developed to predict the simultaneous transformation and transport of nitrogen species. The nitrogen cycle used in the analyses assumes first-order rate coefficients for nitrification, denitrification, immobilization and mineralization between the nitrogen species NH +4, NO -3, organic-N and denitrified fractions. The NO -3-N component in the soil solution was assumed to have negligible adsorption on exchange sites while adsorption of NH +4 was assumed to be represented by a Freundlich type nonlinear isotherm ( S = kdCp). The accuracy and validity of …
Development Of A Combined Quantity And Quality Model For Optimal Unsteady Groundwater Management, Richard C. Peralta, J. Solaimanian, C. L. Griffis
Development Of A Combined Quantity And Quality Model For Optimal Unsteady Groundwater Management, Richard C. Peralta, J. Solaimanian, C. L. Griffis
Civil and Environmental Engineering Faculty Publications
Presented are alternative techniques for including conservative solute transport within computer models for optimizing groundwater extraction rates. Unsteady two-dimensional flow and dispersed conservative solute transport are assumed. Comparisons are made of the practicality of including modified forms of implicit and explicit finite difference solute transport equations within optimization models. These equations can be calibrated and subsequently used within a MODCON procedure. The MODCON modelling procedure consists of an integrated series of five optimization or simulation modules. The procedure is applicable for either an entire aquifer system or for a subsystem of a larger system. The first module, A, computes physically …
Maximizing Reliable Crop Production In A Dynamic Stream/Aquifer System, Richard C. Peralta, K. Kowalski, R. R.A. Cantiller
Maximizing Reliable Crop Production In A Dynamic Stream/Aquifer System, Richard C. Peralta, K. Kowalski, R. R.A. Cantiller
Civil and Environmental Engineering Faculty Publications
A procedure for planning the optimal spatial distribution of crops to be reliably irrigated by conjunctive use of water resources is presented. The implicitly stochastic procedure utilizes. simulation/ optimization model of • stream/ aquifer system. The model utilizes linear optimization, hydrologic influence coefficients and time-varying crop water production functions. It appropriately simulates the time variant, interdependent responses of groundwater levels, stream nap and stream/aquifer interflow to groundwater pumping, and diversion of river water to nonriparian lands. It determines the temporally and spatially varying distribution of groundwater and diverted river water that should be utilized In order to maximizing annual crop …
Optimal Conjunctive Use-Sustained Yield Pumping Analysis For Eastern Arkansas, Rosalinda R.A. Cantiller, Richard C. Peralta, Hossein Azarmnia
Optimal Conjunctive Use-Sustained Yield Pumping Analysis For Eastern Arkansas, Rosalinda R.A. Cantiller, Richard C. Peralta, Hossein Azarmnia
Civil and Environmental Engineering Faculty Publications
The likelihood that irrigated agricultural acreages will increase in eastern Arkansas is high. This results from favorable agricultural soils, climate, and the availability of significant water resources.
Measurement And Simulation Of One-Dimensional Transient Three Phase Flow For Monotonic Liquid Drainage, R. J. Lenhard, J. Dane, J. C. Parker, Jagath J. Kaluarachchi
Measurement And Simulation Of One-Dimensional Transient Three Phase Flow For Monotonic Liquid Drainage, R. J. Lenhard, J. Dane, J. C. Parker, Jagath J. Kaluarachchi
Civil and Environmental Engineering Faculty Publications
Simultaneous movement of oil, water, and air in a sandy porous medium was investigated experimentally under transient flow conditions and results were compared to numerical simulations employing a finite element multiphase flow code. The liquid hydrocarbon was Soltrol 170, a low-density branched alkane mixture. Liquid saturations were measured using a collinear dual-energy gamma radiation apparatus and liquid pressures were measured using hydrophilic (untreated) and hydrophobic (treated) ceramic tensiometers connected to pressure transducers. The experimental regime was selected to impose monotonically draining water and total liquid saturation paths to avoid hysteretic effects. Measured saturations and pressures are compared to values obtained …
Investigation Of Accuracy Limitations Of The Ionospheric Plasma Frequency Probe And Recommendations For A New Instrument, Mark Duane Jensen
Investigation Of Accuracy Limitations Of The Ionospheric Plasma Frequency Probe And Recommendations For A New Instrument, Mark Duane Jensen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A unique wide-range voltage-controlled oscillator (VCO) has been part of the plasma frequency probe (PFP) for many years. The uniqueness of this VCO is how it is tuned with an electronic tuneable inductor in conjunction with a varactor diode. Though the PFP has been utilized successfully for rocketborne ionospheric electron density measurements, fine resolution data was limited by strange frequency jumps (approximately 5 percent uncertainty in electron density) which have appeared in flight results. This thesis examines the cause of some of these jumps, and shows they are instrument related and more particularly caused by the ferrite tank inductor core …
Bioavailable Phosphorus In The Bear River System, Utah, Kenneth Warren Barker
Bioavailable Phosphorus In The Bear River System, Utah, Kenneth Warren Barker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The bioavailable fraction of phosphorus (BAP) in the lower Bear River system waters was investigated. BAP plays a critical role as the limiting nutrient for algal production and eutrophication in proposed reservoirs in the Bear River system. The Bear River system has a hardness ranging between 180-240 mg/L as CaCO3 which significantly affects BAP.
BAP estimation was done by a modified Selenastrum capricornutum Printz Algal Assay Bottle Test. The algal bioassay is considered the best estimator of BAP because no chemical tests or indicator parameters are available. Autoclaving and UV radiation were found to be unacceptable means for sterilization …