Engineering Commons^™

The Great Salt Lake: A Barometer Of Low Frequency Climate Variability, Upmanu Lall, Michael Mann

Reports

Low frequency (interannual or longer period) climatic variability is of interest bacause of its sugnificance for the understanding and prediction of protracted climatic anomalies. Closed basin lakes are sensitive to long term climatic fluctuations and integrate out high frequency variability. It is thus natural to examine the records of such lakes to better understand long term climate dynamics. Here we use Singular Spectral Analysis (SSA) and Multi-Taper Spectral Analysis (MTM) to analyze the time series of Great Slat Lake (GSL) monthly volume changes from 1848-1992, and monthly precipitation, temperature and streamflow for nearby stations with 74 or more years of …

Utah Water Research Laboratory Publications Listing 1989-1994, David S. Bowles, Leaunda S. Hemphill

Reports

No abstract provided.

A Spatially Distributed Energy Balance Snowmelt Model, David G. Tarboton, Tanveer G. Chowdhury, Thomas H. Jackson

Reports

This paper describes an energy balance snowmelt model developed for the prediction of rapid snowmelt rates responsible for soil erosion and water input to a distributed water balance model. The model uses a lumped representation of the snowpack with two state variables, namely, water equivalent and energy content relative to a reference state of water in the ice phase at 0 degrees Celcius. This energy content is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used in a …

Measurements And Modeling Of Snow Energy Balance And Sublimation From Snow, David G. Tarboton

Reports

Snow melt runoff is an important factor in runoff generation for most Utah rivers and a large contributer to Utah's water supply and periodically flooding. The melting of snow is driven by fluxes of energy into the snow during warm periods. These consist of radiant energy from the sun and atmosphere, sensible and latent heat transfers due to turbulent energy exchanges at the snow surface and a relatively small ground flux from below. The turbulent energy exchanges are also responsible for sublimation from the snow surface, particularly in arid environments, and result in a loss of snow water equivalent available …

The Source Hydrology Of Severe Sustained Drought In Th Southwestern U.S., David G. Tarboton

Reports

This paper considers the risk of drought and develops drough scenarios for use in the study of severe sustained drought in the Southwestern United States. The focus is on the Colorado River gbasin and regions to which Colorado River water is exported, especially southern California, which depends on water from the Colorado River as well as the four major rivers in northern California. Drought scenarios are developed using estimates of unimpaired historic streamflow as well as reconstructions of streamflow based on tree ring widths. Drought scenarios in the Colorado River are defined on the basis of annual flow at Lees …

Hycrest Crested Wheatgrass Accelerates The Degradation Of Pentachlorophenol In Soil, A. Ferro, Ronald C. Sims, B. Bugbee

Biological Engineering Faculty Publications

We investigated the effects of vegetation on the fate of pentachlorophenol (PCP) in soil using a novel high-flow sealed test system. Pentachlorophenol has been widely used as a wood preservative, and this highly toxic biocide contaminates soil and ground water at many sites. Although plants are known to accelerate the rates of degradation of certain soil contaminants, this approach has not been thoroughly investigated for PCP. The fate of [14C]PCP, added to soil at a concentration of 100 mg/kg, was compared in three unplanted and three planted systems. The plant used was Hycrest, a perennial, drought-tolerant cultivar of crested wheatgrass …

Introducing Uncertainty Of Aquifer Parameters Into An Optimization Model, Robert L. Ward, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A stochastic analysis is made for a previously described groundwater contaminant management model {Peralta and Ward, 1988). The stochastic model is based on incorporating uncertainty of the aquifer parameters transmissivity and effective porosity into the model. This is accomplished by finding the partial derivative of drawdown with respect to each of these parameters using a Taylor series expansion approximation of the Theis equation. Input that is required for the stochastic version is the mean of the transmissivity and effective porosity, the coefficient of variation of the transmissivity and effective porosity, and a reliability level (0%-100%) . The reliability is a …

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, Ghassan R. Musharrafieh, Richard C. Peralta, Ronald J. Hanks, Lynn M. Dudley

Civil and Environmental Engineering Faculty Publications

Irrigation strategies which maximize crop yield while maintaining target salt concentration in the root zone and/or prevent salt from leaching to the groundwater are computed using a nonlinear, one dimensional, simulation/optimization management model. The included constraint equations maintain a water volume balance and salt transport in the unsaturated zone. Utilized are implicit finite difference forms of the nonlinear, unsteady, unsaturated water flow equation (Richards's equation), and the diffusion-convection solute transport equation. Other constraints include nonlinear functions describing the hydraulic properties of the medium (hydraulic conductivity as a function of matric potential, volumetric water content as a function of matric potential, …

Preventing Pesticide Contamination Of Groundwater While Maximizing Irrigated Crop Yield, Richard C. Peralta, M. A. Hegazy, G. Musharrafieh

Civil and Environmental Engineering Faculty Publications

A simulation/optimization model is developed for maximizing irrigated crop yield while avoiding unacceptable pesticide leaching. The optimization model is designed to help managers prevent non-point source contamination of shallow groundwater aquifers. It computes optimal irrigation amounts for given soil, crop, chemical, and weather data and irrigation frequencies. It directly computes the minimum irrigated crop yield reduction needed to prevent groundwater contamination. Constraint equations used in the model maintain a layered soil moisture volume balance; describe percolation, downward unsaturated zone solute transport and pesticide degradation; and limit the amount of pesticide reaching groundwater. Constraints are linear, piecewise linear, nonlinear, and exponential. …

Modeling Technique For Optimal Recovery Of Immiscible Light Hydrocarbons As Free Product From Contaminated Aquifer, Grant S. Cooper Jr., Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Contamination sites associated with light non-aqueous phase liquids {LNAPL) are numerous and represent difficult cleanup problems. Remediation methods for cleanup of LNAPL fluids in subsurface systems are continuously evolving with the development of various technologies for pump.-and~treat, soil venting, and in-situ bioremediation. Evaluating the effectiveness of remediation techniques as well as attempting to improve their efficiency has been a focus of many researchers, These efforts have included the development of computer simulation models to predict and analyze the fluid movement, entrapment, and mobilization of three~phase systems in porous media. The capability of computer models that not only simulate but optimize …

S/O Modeling Technique For Optimal Containment Of Light Hydrocarbons In Contaminated Unconfined Aquifers, Grant S. Cooper Jr., Jagath J. Kaluarachchi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

An innovative approach is presented to minimize pumping for immobilizing a floating plume of a light non-aqueous phase liquid (LNAPL). The best pumping strategy is determined to contain the free oil product and provide for gradient control of the water table. This approach combined detailed simulation, statistical analysis, and optimization. This modeling technique uses regression equations that describe system response to variable pumping stimuli. The regression equations were developed from analysis of systematically performed simulations of multiphase flow in an areal region of an unconfined aquifer. Simulations were performed using ARMOS, a finite element model. ARMOS can be used simulate …

The Spirit Iii Radiometer Data Compression System, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

In this paper, we describe the image data compressor designed and built for the SPIRIT III radiometer which will be used to provide a real-time "quick-look" capability for the instrument. A a brief description of elements of the radiometer design which determine the data compression requirements is given, followed by a description of the VQ-based hybrid data compression algorithm. Highlights of the hardware design are also discussed.

The performance of the compressor is presented. Tests made using data obtained during cold tests of the instrument indicate an RMS error of 6.26 counts for the 10:1 compression mode and 5.83 counts …

Review Of Planning Distribution Model (Pdm) Status And Application Possibilities For The Egyptian Irigation System, Robert W. Hill, Richard C. Peralta, Gary P. Merkley

Civil and Environmental Engineering Faculty Publications

The comprehensive water management Planning Distribution Model, or PDM, was developed by the Biological and Irrigation Engineering Department, Utah State University (USU), under contract with the United States Bureau of Reclamation (USBR). Most of the work was carried out in the Planning Sector, Ministry of Public Works and Water Resources (MPWWR) , in Cairo, under the Planning Studies and Models Component of the USAID funded Irrigation Management Systems Project.

Optimal Contaminant Plume Management With Us/Wells, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A micro-computer based software package developed at utah State University for computing optimal pumping strategies for well systems (US/WELLS) is demonstrated. US/WELLS is used to determine the optimal time-varying sequence of extraction and injection rates when only limited data is available. The software determines the extraction/injection rates, in pre-specified locations, needed for immobilizing and/or extracting a groundwater contaminant plume. In the optimization problem, the objective function can be either to minimize the extraction/injection rates needed {linear) or to minimize the hydraulic power used for lifting water (quadratic). In either case, different weights can be assigned to emphasize any time period. …

Optimizing Conjunctive Water Use In A Dynamic Stream Aquifer System, Getachew Belaineh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Long-term water management planning models frequently use large time steps and must employ fairly crude assumptions (such as average climatic conditions, etc.). Managing stream aquifer systems during a dry season requires using finer discretization in time and space. Presented is a computer model, US/REMAX, developed by Utah State University personnel for aiding best management of stream-aquifer systems for both long and short eras. The model computes strategies for optimally allocating surface and ground water resources in time and space. For a water supply problem the model can maximize the sum of delivered surface and ground water. For an environmental protection …

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, G. R. Musharrafieh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We developed a simulation-optimization model which maximizes crop yield while maintaining target salt concentration in the root zone, and/ or preventing salt from leaching to the groundwater. The model performs nonlinear optimization and simulation. Implicit finite difference forms of the nonlinear, transient, unsaturated water flow equation, and the convection-diffusion equation are embedded as constraints. Other constraints include nonlinear functions describing the hydraulic properties of the medium. The objectives of the management model is to develop irrigation strategies which prevent salt leaching to the groundwater when salty irrigation water is used. Five different irrigation strategies are developed for Huntington Research Farm, …

A Generalized Data Conversion System, Kevan Morgan

Undergraduate Honors Capstone Projects

To assist in the processing of data files collected by the Space Dynamics Laboratory at Utah State University, the software project GENDACS has been completed. GENDACS, acronym for A Generalized Data Conversion System, will contribute to its research program.

Data are collected from various sensory instruments by the Computer Data Acquisition System. The instrument readings are brought in, tagged with the time they were taken, and stored on an optical disk in a compact, binary (non-ASCII) format. GENDACS is designed so that the program can read in such files, sort out the data, and convert them into a new ASCII …

Climatic Variability And Dynamics Of Great Salt Lake Hydrology, Taiye B. Sangoyomi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The time evolution of the Great Salt Lake hydro-climatic system is studied from the perspective of nonlinear dynamics. The dynamics are reconstructed in phase space using the Great Salt Lake volume time series. Important attributes for describing the system are then obtained from the reconstructed space. These include the minimum number of state variables required to describe the system inferred from a determination of the intrinsic dimension, and characterization of the system in terms of linear/nonlinear, and deterministic/stochastic. Other attributes obtained are the dominant modes of behavior of the system, as well as the limit of predictability or information loss, …

Practical Optimization Modeling For Contaminant Plume Management, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to greatly speed the process of computing desirable groundwater pumping strategies for plume management. They make the process of computing optimal strategies fairly straightforward and can help minimize the labor and cost of groundwater contaminant clean-up.

Analysis Of Cutthroat Flume Discharge Ratings, Liyan Ren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sixteeen sets of original laboratory data collected by many investigators for various Cutthroat flume sizes are thoroughly reviewed and organized. Best-fit discharge parameters are obtained by performing the free-flow analysis and the submerged-flow analysis. Then, the transition submergence can be calculated. Afterwards, the unified free-flow and submerged-flow discharge parameters are developed for each flume size in order to generalize the calibrations for Cutthroat flumes. This is a very tedious process requiring a trial-and-error approach. Finally, comparisons are made of the measured laboratory discharges with the predicted discharges for both free flow and submerged flow using both the best-fit and the …

A Mechanistic Approach To Modeling Habitat Needs Of Drift-Feeding Salmonids, R. Craig Addley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mechanistic model is developed to determine the habitat needs of drift-feeding stream salmonids from the direct cause-and-effect relationships of environmental and physiological variables on net energy intake (NEI). The model determines NEI by subtracting energy costs (basal metabolism, swimming cost, digestion cost) and losses (egestion and excretion) from the gross energy intake obtained as a result of simulated prey capture. The prey capture portion of the model utilizes components of the predation model of C.S. Holling and the prey capture model of N.F. Hughes and L.M. Dill to determine the rate of prey capture (gross energy intake) as a …

Probable Maximum Flood Estimation In Northern Utah, Khin Maung Win

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The probable maximum flood (PMF) is used for the xxi assessment of maximum flood potentials in spillway sizing of new dams and in evaluating the adequacy of existing hydrologic structures. Determination of the PMF begins with the estimation of the probable maximum precipitation (PMP) for a particular dam site. Selecting hydrologic methods and assumptions for converting PMP to PMF, which are most appropriate for Utah conditions, is important to meet current inflow design flood (IDF) safety standards.

The objectives of this study were (a) to demonstrate a maximization approach to PMF determination, (b) to evaluate effects of basin characteristics and …

Jet Velocity Dissipation And Modelling With Aeration, Stephen J. Schlenker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of natural aeration and fall height upon velocity dissipation and modelling were studied. Underwater velocities and void ratios (proportion of air volume to total volume) were measured along the jet centerline at various depths in the receiving pool under 1- and 2-inch diameter vertical circular free-falling jets. Maximum air bubble penetration depths were also measured. In the tests, the nozzle velocities were designed so that the two differently sized models would have equivalent Froude numbers for direct comparison of respective underwater parameters. Air entrainment-the natural development of air bubbles within a pool receiving a free-falling jet-causes voids to …

Heating Of Calcium Phosphate Crystals: Morphological Consequences And Biological Implications, W. Bohne, J. A. Pouezat, L. Peru, G. Daculsi

Cells and Materials

Sintering hydroxyapatite (HA) and ß-tricalcium phosphate (ß-TCP) affects the chemical composition, the crystallinity, and the morphological features as demonstrated by means of X-ray diffraction (XRD) , infrared spectroscopy (IR), and scanning electron microscopy (SEM). When heated to 1230°C, 16.7% of HA had decomposed to ß-TCP. SEM investigations showed homogeneous, sharp angular polyhedric blocks of 30 to 50 µm with rare surface pores. On heating at 1230°C, ß-TCP had entirely transformed to a-TCP. During sintering, the size of the powder grains increased and progressive bridging between the grains was observed. At 1230°C, a network within round-shaped polyhedric blocks of 50 to …

Surface Subsidence Over A Room-And-Pillar Mine In The Western United States, United States Department Of The Interior, Bureau Of Mines

Mines and Mineral Resources

This report summarizes the results from the subsidence research study completed by the U.S. Bureau of Mines at the Roadside Mine, Powderhorn Coal Co., Palisade, CO. This research was conducted from February 1981 to August 1985, with additional data obtained during July 1991, to evaluate residual subsidence. The Bureau studied subsidence at three distinct room-and-pillar sections at separate locations over the mine and determined the maximum subsidence values and surface subsidence profiles for each mining section. Maximum subsidence of 3.0 ft. occurred over the room-and-pillar sections, with over-burden depths ranging from 50 to 600 ft. Surface tension cracks had occurred, …

Bone Growth On Sol-Gel Calcium Phosphate Thin Films In Vitro, Q. Qiu, P. Vincent, B. Lowenberg, M. Sayer, J. E. Davies

Cells and Materials

Thin, sub-micron, films of calcium phosphate were fabricated on either glass or quartz supports by a colloidal suspension sol-gel method. These films, which varied in both surface chemistry and topography were then employed as culture substrata for osteogenic rat bone marrow cells. During an 18 day culture period, the cells elaborated a morphologically distinguishable bone matrix on all substrata which was similar to that reported earlier on tissue culture polystyrene. Selected samples of the culture substrata were fractured, critical point dried, and observed by scanning electron microscopy. Particular attention was paid to the morphologies of the interface between the so1-gellayer …

Mineralized Matrix Synthesis By Isolated Mouse Odontoblast-Like Cells In Vitro, P. B. Andrews, A. R. Ten Cate, J. E. Davies

Cells and Materials

First mandibular molar tooth germs were dissected from 17 day mouse embryos. The dental papilla was isolated using both mechanical separation and enzymatic digestion. The cells of the papilla were then enzymatically disaggregated and cultured in 35 mm polystyrene dishes containing alpha minimum essential medium supplemented with 15 % fetal calf serum, 50 μglml ascorbic acid, 1 o-8 M dexamethasone and 10 mM Na-13-glycerophosphate. The cultures were maintained for 23 days. The cultured cells initially appeared as large flat cells having numerous cell processes. Multilayered cell nodules, distributed randomly in the cultures, were apparent after 5 days. Matrix was visible …

Ultrastructural, Cytochemical, And Immunocytochemical Studies On Bone And Its Interfaces, M. D. Mckee, A. Nanci

Cells and Materials

Bone cells possess the ability to synthesize, secrete and direct the assembly and maintenance of extracellular matrix to form a functionally rigid and/or weight-bearing mineralized tissue complex, the skeleton. The skeleton not only supports and protects the organs and tissues of the body, but also acts as a mineral ion reservoir for maintaining systemic calcium balance (calcium homeostasis). The remarkable biological precision necessary for the formation, turnover and constant adaptation of bone to external mechanical forces is a dynamic process requiring a coordinated cellular effort relying on a variety of cell-cell and cell-matrix/mineral interactions. Indeed, cell-matrix interfaces found in a …

Multinucleated Giant Cells-Hydroxyapatite Interactions: A Time-Related Quantitative Study In A Rat Skull Defect, J. M. Dersot, A. Llorens, J. L. Saffar

Cells and Materials

The implantation of calcium phosphate ceramics in the bone environment elicits the differentiation of multinucleated giant cells (MNGCs). MNGC interactions with both crushed and standard hydroxyapatite (HA, Bioapatite ®) particles (cHA and sHA) were studied in rat skull defects. Light microscopy (LM) of undemineralized material after 21 and 42 days of implantation showed that the number of particles in the defect significantly decreased (about SO%) with the two HA forms. Concomitantly, average cHA particle size increased significantly due to the elimination of the smallest particles by the MNGCs. The number of MNGCs per mm2 of defect decreased significantly between 21 …

Evaluation Of Drug Delivery Systems By Electron Microscopy Techniques, Y. V. Pathak, V. D. Labhashetwar

Cells and Materials

This review covers the applications of electron microscopic techniques to the characterization and evaluation of drug delivery systems. Various electron microscopic (EM) related techniques such as transmission electron microscopy, scanning electron microscopy (SEM), SEM with energy dispersive X-ray microanalysis, and freeze-fracture electron microscopy are extensively used for this purpose. Microcapsules, microspheres, nanocapsules, liposomes , polymeric carriers and other drug delivery systems are characterized using EM related techniques for their surface topography, size and shape analysis, biodegradation, in vitro - in vivo evaluation and drug excipient interactions and characterization. Electron microscopy methods are very useful in understanding the mechanism of drug …