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Full-Text Articles in Engineering

Preliminary Evaluation Of The Effects Of A Pumping Well On Existing Surface Water Resources Located In T. 12n, R. 2e, Sec. 23, Cache And Box Elder Counties, Denny J. Johnson, Richard C. Peralta Nov 1996

Preliminary Evaluation Of The Effects Of A Pumping Well On Existing Surface Water Resources Located In T. 12n, R. 2e, Sec. 23, Cache And Box Elder Counties, Denny J. Johnson, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This report contains the results of a preliminary study of the impact of pumping a well located in T. 12N, R. 2E, sec. 23, Cache and Box Elder Counties, Utah. A semianalytical capture zone analysis was performed to determine if pumping at the well is likely to reduce flow in Willow Creek or any of three springs in the surrounding area. The well has been used from 1974 to present and is sometimes pumped at 90 gallons per minute (gpm) (verbal communication, Veibell, 1996).


On Hack's Law, Riccardo Rigon, Ignacio Rodriguez-Iturbe, Amos Maritan, Achille Giacometti, David G. Tarboton, Andrea Rinaldo Nov 1996

On Hack's Law, Riccardo Rigon, Ignacio Rodriguez-Iturbe, Amos Maritan, Achille Giacometti, David G. Tarboton, Andrea Rinaldo

Civil and Environmental Engineering Faculty Publications

Hack's law is reviewed, emphasizing its implications for the elongation of river basins as well as its connections with their fractal characteristics. The relation between Hack's law and the internal structure of river basins is investigated experimentally through digital elevation models. It is found that Hack's exponent, elongation, and some relevant fractal characters are closely related. The self-affine character of basin boundaries is shown to be connected to the power law decay of the probability of total contributing areas at any link and to Hack's law. An explanation for Hack's law is derived from scaling arguments. From the results we …


Software For Optimizing Groundwater Or Conjunctive Water Management, Richard C. Peralta, Alaa H. Aly Jun 1996

Software For Optimizing Groundwater Or Conjunctive Water Management, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

US/REMAX is a computer program designed to assist water managers in developing optimal groundwater and/or surface water strategies for a wide range of management problems. It employs response matrix, regression and other methods adapted for nonlinear systems. US/REMAX performs deterministic or reliability-based, single- or multi-objective optimization. Decision variables are ground-water extraction/injection and/or surface water diversion. State variables include water flows, stages and concentrations. Hard coded objective functions and constraints are linear, nonlinear, integer or mixed integer. Special constraints can be added to address unusual situations.


Toward A Balanced Strategy To Address Contaminated Groundwater Plumes At The Massachusetts Military Reservation, Richard C. Peralta May 1996

Toward A Balanced Strategy To Address Contaminated Groundwater Plumes At The Massachusetts Military Reservation, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This document contains the findings and recommendations of the Technical Review and Evaluation Team (TRET) for the plume containment project at the Massachusetts Military Reservation (MMR). The findings and recommendations are in response to the 60 Percent Plume Containment Design, submitted by Operational Technologies (OpTech) in January 1996. In short, the TRET recommends the MMR depart substantially from the strategy of simultaneous, 100 percent containment and treatment that was assigned to OpTech for design in accordance with the Record of Decision (ROD) for Interim Action. This strategy guided the course of the plume containment project over the past two years


A Spatially-Distributed Hydrologic Model For A Small Arid Mountain Watershed, Thomas H. Jackson, David G. Tarboton, Keith R. Cooley May 1996

A Spatially-Distributed Hydrologic Model For A Small Arid Mountain Watershed, Thomas H. Jackson, David G. Tarboton, Keith R. Cooley

Civil and Environmental Engineering Faculty Publications

A distributed water balance model was developed as a part of an intensive-field study to simulate the snowmelt-driven hydrologic response of a small mountain watershed using measured values of solar radiation, wind speed, air temperature, relative humidity and precipitation as input.

Snowmelt and evapotranspiration were modeled with point energy balances, written in terms of the snow surface and soil surface temperatures, respectively, corrected for local topographic characteristics and snow drifting. Meltwater was routed to the basin outlet as topography-driven, saturated subsurface flow, with all flow in excess of local transmissivity taken as surface runoff.

The model was calibrated with 1985-6 …


A Nonparametric Wet/Dry Spell Model For Resampling Daily Precipitation, Upmanu L. Lall, Balaji Rajagopalan, David G. Tarboton Apr 1996

A Nonparametric Wet/Dry Spell Model For Resampling Daily Precipitation, Upmanu L. Lall, Balaji Rajagopalan, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

A nonparametric wet/dry spell model is developed for resampling daily precipitation at a site. The model considers alternating sequences of wet and dry days in a given season of the year. All marginal, joint, and conditional probability densities of interest (e.g., dry spell length, wet spell length, precipitation amount, and wet spell length given prior to dry spell length) are estimated nonparametrically using at-site data and kernel probability density estimators. Procedures for the disaggregation of wet spell precipitation into daily precipitation and for the generation of synthetic sequences are proffered. An application of the model for generating synthetic precipitation traces …


Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Mather Afb, California, Richard C. Peralta, Alaa H. Aly Mar 1996

Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Mather Afb, California, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

USU first estimated the future TCE concentrations that would result if no pumping strategy were implemented (Figure 5, Scenario AO). Then USU used the procedure of Appendix B with the model formulation of Appendix C to compute optimal pumping strategies. In computing optimal strategies USU cycled until an arbitrary three percent contaminant mass convergence criterion was satisfied.


Effect Of Subsurface Heterogeneity On Free-Product Recovery From Unconfined Aquifers, Jagath J. Kaluarachchi Mar 1996

Effect Of Subsurface Heterogeneity On Free-Product Recovery From Unconfined Aquifers, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Free-product record system designs for light-hydrocarbon-contaminated sites were investigated to evaluate the effects of subsurface heterogeneity using a vertically integrated three-phase flow model. The input stochastic variable of the areal flow analysis was the log-intrinsic permeability and it was generated using the Turning Band method. The results of a series of hypothetical field-scale simulations showed that subsurface heterogeneity has a substantial effect on free-product recovery predictions. As the heterogeneity increased, the recoverable oil volume decreased and the residual trapped oil volume increased. As the subsurface anisotropy increased, these effects together with free- and total-oil contaminated areas were further enhanced. The …


A Hybrid-Seed Smart Pixel Array For A Four-Stage Intelligent Optical Backplane Demonstrator, David R. Rolston, David V. Plant, Ted H. Szymanski, Harvard Scott Hinton, W. S. Hsiao, Michael H. Ayliffe, David Kabal, Michael B. Venditti, P. Desai, Ashok V. Krishnamoorthy, Keith W. Goossen, J. A. Walker, B. Tseng, S. P. Hui, J. C. Cunningham, W. Y. Jan Jan 1996

A Hybrid-Seed Smart Pixel Array For A Four-Stage Intelligent Optical Backplane Demonstrator, David R. Rolston, David V. Plant, Ted H. Szymanski, Harvard Scott Hinton, W. S. Hsiao, Michael H. Ayliffe, David Kabal, Michael B. Venditti, P. Desai, Ashok V. Krishnamoorthy, Keith W. Goossen, J. A. Walker, B. Tseng, S. P. Hui, J. C. Cunningham, W. Y. Jan

Electrical and Computer Engineering Faculty Publications

This paper describes the VLSI design, layout, and testing of a Hybrid-SEED smart pixel array for a four-stage intelligent optical backplane. The Hybrid-SEED technology uses CMOS silicon circuitry with GaAs-AlGaAs multiple-quantum-well modulators and detectors. The chip has been designed based on the HyperPlane architecture and is composed of four smart pixels which act as a logical 4-bit parallel optical channel. It has the ability to recognize a 4-bit address header, inject electrical data onto the backplane, retransmit optical data, and extract optical data from the backplane. In addition, the smart pixel array can accommodate for optical inversions and bit permutations …


An Atm-Based Intelligent Optical Backplane Using Cmos-Seed Smart Pixel Arrays And Free- Space Optical Interconnect Modules, Dominic J. Goodwill, Kent E. Devenport, Harvard Scott Hinton Jan 1996

An Atm-Based Intelligent Optical Backplane Using Cmos-Seed Smart Pixel Arrays And Free- Space Optical Interconnect Modules, Dominic J. Goodwill, Kent E. Devenport, Harvard Scott Hinton

Electrical and Computer Engineering Faculty Publications

The architecture, smart pixel array chip design, and optical design of an intelligent free-space digital optical backplane for ATM switching are presented. The smart pixel chip uses reflective SEED (self-electrooptic effect device) optical modulators and detectors flip-chip bonded to CMOS circuitry. This chip is one of the most complex designs ever reported in this technology, and it operates at a simulated backplane clock rate of 125 MHz. The low-loss optical system employs f/4 diffractive minilenses and microlenses to interconnect clusters of smart pixels, and it is shown to allow 2060 connections per chip if 1-cm2 -sized smart pixel chips are …


Progress In The Smart Pixel Technologies, Harvard Scott Hinton Jan 1996

Progress In The Smart Pixel Technologies, Harvard Scott Hinton

Electrical and Computer Engineering Faculty Publications

The purpose of this paper is to review the recent progress in the developing smart pixel technologies. The paper begins by reviewing some of the rapidly evolving smart pixel terminologies. It then describes several of the smart pixel technologies that have recently emerged. Finally, it outlines the performance of these technologies in both device complexity and aggregate capacity. The reviewed SPA technologies include both the modulator-based FET-SEED, hybrid CMOS-SEED, and LCOS smart pixels and the source-based hybrid VCSEL/MSM, ELO, flip-chip-bonded VCSEL/MSM, and monolithic MSM/MESFET/VCSEL smart pixels.


Design, Modeling, And Characterization Of Fet-Seed Smart Pixel Transceiver Arrays For Optical Backplanes, David V. Plant, Alain Z. Shang, Marcos R. Otazo, David R. Rolston, Brian Robertson, Harvard Scott Hinton Jan 1996

Design, Modeling, And Characterization Of Fet-Seed Smart Pixel Transceiver Arrays For Optical Backplanes, David V. Plant, Alain Z. Shang, Marcos R. Otazo, David R. Rolston, Brian Robertson, Harvard Scott Hinton

Electrical and Computer Engineering Faculty Publications

The design, modeling, and characterization of FET-SEED smart pixel transceiver arrays fabricated for application in optical backplanes are presented. Results of digital and analog measurements on 4×4 transmitter arrays and 4×4 receiver arrays, packaged at the printed circuit-board level, will be presented. In addition, these results will be compared to device and circuit models developed for these optoelectronics. Finally, the description of the successful application of these optoelectronics to interconnect two printed circuit boards will be described.


The Study Of The Resistance And Stability Of Vegetation Ecosystem Plant Groupings In Flood Control Channels: Vol. 1, William Rahmeyer, David Werth Jan 1996

The Study Of The Resistance And Stability Of Vegetation Ecosystem Plant Groupings In Flood Control Channels: Vol. 1, William Rahmeyer, David Werth

Reports

Preface: The following report was prepared by the utah Water Research Laboratory of Utah State University in Logan, Utah. Volume 1 of the UWRL report USU--400A contains the data summary and conclusions of flow tests conducted with different plant types and ecosystem groupings of shrubs and woody vegetation in the hydraulics flumes of Utah State University. The methodology and equations that were developed to predict flow resistance for fultiple plant types include the effects of plant fexibility, varying plant density, plant characteristics, and multiple plant stems. The study included over 214 flow tests, testing of 20 different plant types, 5 …


Utah Water Research Laboratory Publications Listing 1993-1996, David S. Bowles, Leaunda S. Hemphill Jan 1996

Utah Water Research Laboratory Publications Listing 1993-1996, David S. Bowles, Leaunda S. Hemphill

Reports

No abstract provided.


Cache County Water Demand/Supply Model, Trevor C. Hughes, Gregory J. Norby, Laxman Thyagarajan Jan 1996

Cache County Water Demand/Supply Model, Trevor C. Hughes, Gregory J. Norby, Laxman Thyagarajan

Reports

This report descibes a municipal water demand forecasting model for use in areas of mixed rural and urban housing types. A series of residential demand functions were derived which forecast water demand based on the ype and density of housing and season. Micro sampling techniques were used to correlate water use data and explanatory variable data for low, medium, and high density housing. The demand functions were incorporated into a geographic information system (GIS) platform cosisting of a desk-top mapping program, MapInfo, coupled with a user interface program written in Visual Basic. The GIS-based model analyzes water demand at the …