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Bioconcentrations Of Heavy Metals Copper, Chromium (Tot), Lead, Zinc, Nickel And Mercury In The Missouri River 1991 Jan 1991

Bioconcentrations Of Heavy Metals Copper, Chromium (Tot), Lead, Zinc, Nickel And Mercury In The Missouri River 1991

United States Army Corps of Engineers, Omaha District

The presence of heavy metals within aquatic environments can be attributed to sources such as industry, municipal discharges, agriculture and natural processes which release various amounts into natural systems. Metals such as copper, zinc and chromium are listed as essential micronutrients for many plant and animal species. Of potential concern, however, is the tendency of heavy metals to accumulate within the food webs of ecosystems. Classified as biologically hard to degrade, heavy metals may concentrate to significant amounts within the trophic levels of a particular ecosystem. At these increased concentrations many of these heavy metals become toxic to living organisms. …


Assessing Pesticide Contamination To Groundwater: A Rapid Approach, Majid Ehteshami, Richard C. Peralta, Hubert Eisele, Howard M. Deer, Terry Tindall Jan 1991

Assessing Pesticide Contamination To Groundwater: A Rapid Approach, Majid Ehteshami, Richard C. Peralta, Hubert Eisele, Howard M. Deer, Terry Tindall

Civil and Environmental Engineering Faculty Publications

A methodology has been developed for identifying hazardous pesticides/site combinations threatening ground-water contamination. Screening methodologies are required to determine which locations and pesticides now in use should receive the greatest attention to safeguard the public health. The presented method uses a hazard to ground-water hydrogeological screening model (DRASTIC) and employs a one-dimensional pesticide transport model ( CMLS). The method is an efficient and practical technique to identify where particular combinations of pesticides, water management practices, soils, and geology result in the greatest potential hazard to ground-water contamination. Use of the presented approach can reduce sampling needs and expense.


Studies Related To Nutrients Entering Groundwater From The Heber Valley Sewer Farm And Dairies, Roland W. Jeppson, Joan Mclean, Calvin G. Clyde, Scott Korom Jan 1991

Studies Related To Nutrients Entering Groundwater From The Heber Valley Sewer Farm And Dairies, Roland W. Jeppson, Joan Mclean, Calvin G. Clyde, Scott Korom

Reports

Foreword: This report includes the results from a two year study in the Heber Valley to determine amounts of nutrients that are entering the groundwaters of the Heber Valley, and might ultimately enter Deer Creek Reservoir. Since Deer Creek Reservoir in Heber Valley, Utah supplies approximately 65 percent of the water distributed to Salt Lake County, the maintenance of its quality is of considerable importance. To maintain the quality of this reservoir and limit its eutrophication "best management" practices for surface water have been implemented gradually during the past decade in Heber Valley. These practices have significantly improved the qualities …


Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith Jan 1991

Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith

Engineering Management & Systems Engineering Theses & Dissertations

Capitalism developed where and when it did because there was high information access. There was high information access because of a major advance in information technology--the press. Where the technology was not controlled by the "powers that be" there was economic growth and a shift in the entire social structure. Where it was controlled there was no structural change and there was economic ruin. The development of capitalism is a major step change in economic growth. It is also a major change in the way people organize themselves into groups.

Major step changes in the growth and in the organization …


Biodegradation Of Hexachlorocyclohexane In Sand And Wastewater Using Immobilized Phanerochaete Chrysosporum, Ajaykumar C. Gami Dec 1990

Biodegradation Of Hexachlorocyclohexane In Sand And Wastewater Using Immobilized Phanerochaete Chrysosporum, Ajaykumar C. Gami

Theses

The present study was carried out in order to assess the ability of Phanerochaete chysosporium to degrade lindane (hexachlorocyclohexane) in sand as well as in water. It was found that the fungus is immobilized on saw dust, it is able to degrade lindane in a packed-bed reactor configuration, with a first-order rate constant of 0.00066min-1. The fungus is also able to degrade lindane in sand. As with the packed-bed reactor, a supplemental carbon source (glucose) is required. In this study it was found that a glucose concentration of 20 gm/kg of sand, and 40% w/w moisture content, give …


Renewable Energy Activities For Middle Grades, Florida Solar Energy Center, David Lahart Dec 1990

Renewable Energy Activities For Middle Grades, Florida Solar Energy Center, David Lahart

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) is a research and education arm of the State University System hosted by the University of Central Florida. The Florida legislature established FSEC in 1974 to conduct research in alternative energy technologies, to ensure the quality of solar energy equipment sold in Florida, and to educate people about renewable energy technology.

One method of disseminating research results has been through teacher education programs and the development of instructional materials. FSEC-developed materials are designed to teach science and social studies research methods and/or process skills. The units have been field-tested and correlated with student performance …


A Low-Cost Part-Task Flight Training System: An Application Of A Head Mounted Display, David A. Dahn Dec 1990

A Low-Cost Part-Task Flight Training System: An Application Of A Head Mounted Display, David A. Dahn

Theses and Dissertations

To investigate the feasibility of using head-mounted display(HMD) and Computer Image Generators(CIG) in a low cost part-task trainer, we created a prototype system. Our approach was to build a virtual world interface using a HMD to an existing flight simulator application. This allowed a CIG with only one graphics channel to drive the display. To investigate which class of computing platform was suitable for use as the CIG, a cooperative thesis effort was launched to host the simulator on a mini-computer and micro-computer platform. The appropriate CIG could then be determined through demonstration and comparison between the systems. A software …


Speech Coding And Compression Using Wavelets And Lateral Inhibitory Networks, Richard Ricart Dec 1990

Speech Coding And Compression Using Wavelets And Lateral Inhibitory Networks, Richard Ricart

Theses and Dissertations

The purpose of this thesis is to introduce the concept of lateral inhibition as a generalized technique for compressing time/frequency representations of electromagnetic and acoustical signals, particularly speech. This requires at least a rudimentary treatment of the theory of frames-which generalizes most commonly known time/frequency distributions--the biology of hearing, and digital signal processing. As such, this material, along with the interrelationships of the disparate subjects, is presented in a tutorial style. This may leave the mathematician longing for more rigor, the neurophysiological psychologist longing for more substantive support of the hypotheses presented, and the engineer longing for a reprieve from …


Irish Building Services News Dec 1990

Irish Building Services News

Building Services Engineering

No abstract provided.


Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration Dec 1990

Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration

Publications (WR)

The Lake Mead Fertilization Project is a research program designed to investigate the potential for using large-scale artificial fertilization to enhance the game fisheries of this reservoir through an increase in the population of threadfin shad, the system's primary forage species. A substantial decline in the population of largemouth bass, together with poor condition of adult striped bass, are the two major issues affecting the Lake Mead game fisheries. Both issues have been hypothesized to be a result of an inadequate amount of forage in the reservoir. Previous studies have in turn suggested that a major factor limiting the shad …


Graphical Representation Of Parallel Algorithmic Processes, Edward M. Williams Dec 1990

Graphical Representation Of Parallel Algorithmic Processes, Edward M. Williams

Theses and Dissertations

Algorithm animation is a visualization method used to enhance understanding of functioning of an algorithm or program. Visualization is used for many purposes, including education, algorithm research, performance analysis, and program debugging. This research applies algorithm animation techniques to programs developed for parallel architectures, with specific on the Intel iPSC/2 hypercube. While both P-time and NP-time algorithms can potentially benefit from using visualization techniques, the set of NP-complete problems provides fertile ground for developing parallel applications, since the combinatoric nature of the problems makes finding the optimum solution impractical. The primary goals for this visualization system are: Data should be …


Design And Fabrication Of An Implantable Cortical Semiconductor Integrated Circuit Electrode Array, Pierre K. Lefevre Dec 1990

Design And Fabrication Of An Implantable Cortical Semiconductor Integrated Circuit Electrode Array, Pierre K. Lefevre

Theses and Dissertations

This research furthered the processing steps of the AFIT 16 by 16 implantable cortical semiconductor integrated circuit electrode array, or brain chip. The areas of interest include the brain chip electron ics, metallization, ionic permeation, and implantation. The electronics and metallization are heavily covered. A high speed, single clock divide-by-two circuit was modified with a reset transistor and cascaded to form a ripple counter. This device had stable operation at specific source voltage and clock voltage and frequency. A 7-stage inverter with 10 unmodified divide-by-two circuits cascaded operated between 1.7 and 8 volts, and between 39 Khz and 1 Mhz, …


Analysis Of Visual Illusions Using Gabor Filters, Richard A. Oberndorf Dec 1990

Analysis Of Visual Illusions Using Gabor Filters, Richard A. Oberndorf

Theses and Dissertations

This thesis has demonstrated the correctness of using spatial filters in the analysis of various visual illusions; the specific form of filter has been derived from a Gabor equation model of simple cell response on the visual cortex. The Gabor Low Pass Filter (GLPF) applied to these anomalies was derived from proposals made that simple cell response on the visual cortex may be modeled by a set of equations originally proposed by Gabor in the 1940's. Based upon the extension of these equations into two dimensions, a GLPF process was applied to computer-generated black and white illusions (the Kanizsa Triangle, …


An Evaluation Of An Ada Implementation Of The Rete Algorithm For Embedded Flight Processors, F. Jesse Fanning Dec 1990

An Evaluation Of An Ada Implementation Of The Rete Algorithm For Embedded Flight Processors, F. Jesse Fanning

Theses and Dissertations

The purpose of this thesis was to design and develop an expert system shell in Ada, and to evaluate the shell's execution and size performance to determine its suitability for real-time operation on the MIL-STD-1750A embedded flight processor. The expert system shell uses the CLIPS/Ada inference engine, a forward-chaining Ada implementation of Rete. The expert system shell design is presented along with an overview of the target environment--the MIL-STD-1750A VHSIC Avionic Modular Processor (VAMP) running under the Ada Avionics Real-Time Software (AARTS) Operating System. Theoretical and empirical complexity analyses of the inference engine are presented and discussed in view of …


Ligament Reconstruction : A Biomechanical Cadaveric Test Of Autogenous Repairs And The In Vivo Evaluation Of Synthetic Scaffold Materials, Anne Marie Daly Sep 1990

Ligament Reconstruction : A Biomechanical Cadaveric Test Of Autogenous Repairs And The In Vivo Evaluation Of Synthetic Scaffold Materials, Anne Marie Daly

Theses

The knee joint is the largest and one of the most complex joints in the human body. The anterior cruciate ligament (ACL) is one of the major intra-articular ligaments responsible for controlling and guiding the knee through most of its range of motion and its rupture alters normal joint mechanics.

One objective of this thesis was to determine if two autogenous tissue ACL reconstruction methods were biomechanically equivalent. The first method using the central one-third of the patellar tendon has been used clinically since the early 1960s. The second method utilizes portions of both the semitendinosus and the iliotibial band. …


A Transputer Based Distributed Graphics Display, Ramana V. Kattula Sep 1990

A Transputer Based Distributed Graphics Display, Ramana V. Kattula

Theses

The design of a transputer based graphics display is discussed. The problems associated with the single processor graphics systems are described. A solution based on multiple transputers is proposed. The transputer based graphics display described is a general purpose graphics system which can achieve any required compute performance and drawing performance without using special hardware. The display resolution and color depth can be enhanced as per the user requirements with little or no change in hardware.


Landmark-Based Partial Shape Recognition By A Two-Stage Bam Neural Network, Xianjun Liu Sep 1990

Landmark-Based Partial Shape Recognition By A Two-Stage Bam Neural Network, Xianjun Liu

Theses

In this thesis, we develop a Bitfirectional Associative Memory (BAM) based neural network to achieve partial shape recognition. To recognize objects which are partially occluded, we represent each object by a set of landmarks. The landmarks of an object are points of interest relative to the object that have important shape attributes. To achieve recognition, feature values (landmark values) of each model object are trained and stored in the network. Each memory cell is trained to store landmark values of a model object for all possible positions. Given a scene which may consist of several objects, landmarks in the scene …


32nd Rocky Mountain Conference Jul 1990

32nd Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 32nd annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 29 - August 3, 1990.


Impulse, Kara Donohue Jul 1990

Impulse, Kara Donohue

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page 2] Sander named engineering dean
[Page 3] Students create model of proposed laboratory
[Page 4] Kurtenbach named Distinguished Engineer
[Page 5] Governor creates Buckley award
[Page 5] Merit service award named for Buckley
[Page 5] Structural seminar draws many speakers

Special Section: Entrepreneurship:
[Page 6] Governor's proclamation
[Page 7-9] Entrepreneurs' Workshop offers training for successful business ventures
[Page 9] A letter from President Robert Wagner
[Page 10] Jerry Lohr to share his vision for entrepreneurial achievement
[Page 11] Engineering students excel in journalism
[Page 12] Entrepreneurs' Workshop schedule and registration form

Departments:
Alumni
[Page 13] Alumnus launches hydraulics …


Irish Building Services News Jul 1990

Irish Building Services News

Building Services Engineering

No abstract provided.


Coke Oven Emissions: A Case Study Of Technology-Based Regulation, John D. Graham, David R. Holtgrave Jun 1990

Coke Oven Emissions: A Case Study Of Technology-Based Regulation, John D. Graham, David R. Holtgrave

RISK: Health, Safety & Environment (1990-2002)

After examining and analyzing the experience with coke ovens, the authors conclude that attempts to force technology beyond its demonstrated competence can be both expensive and ineffective in controlling hazards. They also suggest implications for pending proposals to further control air pollution.


Computer Modeling And Analysis Of Biological Rhythms, Shi Xiong Yang May 1990

Computer Modeling And Analysis Of Biological Rhythms, Shi Xiong Yang

Dissertations

Biological rhythms are an important phenomenon and feature of physiologic systems. Indirect means have to be employed for their description and exploration due to the unclear internal nature of the system. This study analyzed and developed several possible mathematical models using single or multidimensional nonlinear differential equations to approach the experimental circadian data. The numerical solutions of the models were obtained by computer simulation and the simulated and experimental acquired circadian data were analyzed in both the time and frequency domains. Phase plane plots, phase response curves and power spectrum analysis were employed to determine the nonlinearity of the system …


A Comparison Of Integrated And Differential Estimates Of Flourescent Intensity Profiles Using Digital Video Image Analysis, Langfang Wu May 1990

A Comparison Of Integrated And Differential Estimates Of Flourescent Intensity Profiles Using Digital Video Image Analysis, Langfang Wu

Theses

The dynamics of macromolecular transport across microvascular walls in the hamster cheek pouch have previously been studied by other investigators using fluorescence intravital microscopy. Fluorescein Isothiocyanate labeled Dextrans (FITC-Dx) of 20,000, and 70,000 molecular weight (FITC-Dx-20 and FITC- Dx-70) were used as macromolecular probes. Values of fluorescent intensity were previously recorded on videotape as a function of distance perpendicular to leaking vessels over a period of about 2.5 hr to allow for tracer equilibration in the interstitial space. In this study, these videotapes were played back frame-by-frame and 215x130-pixel windows around each leaking vessel were selected for further analysis of …


Eeg Mapping Using The Personal Computer, Zhuan-Zhang Pei May 1990

Eeg Mapping Using The Personal Computer, Zhuan-Zhang Pei

Theses

An approach for brain electrical activity mapping using a personal computer has been investigated to enhance the visibility of the EECs. An automatic procedure from data acquisition to the final mapping has been developed for on-line or off-line data processing, in which a table-look-up technique has been introduced to eliminate redundant processing. The power spectra in different EEC frequency bands for four electrodes are coded into 15 colors and mapped on a color monitor. The data correspondings to the areas between electrodes are interpolated by the surface spline method. The mapping speed and smoothness has been optimized. An experiment has …


Finite Element Stress Analysis Of Engine Piston, Anil Nanalal Mistry May 1990

Finite Element Stress Analysis Of Engine Piston, Anil Nanalal Mistry

Theses

In this analysis, Ford Motor Company's, modular engine seriespiston was selected for the analysis purposes. The engine has a capacity of 4.6 liter, V-8 cylinder and with 2 valves.The piston is made of aluminum alloy material Z-16-T6. A three-dimensional finite element model was created to analyze the piston. The model, which contains only the quarter section of the piston due to loading symmetry and geometry, was used to calculate operating temperatures and the corresponding thermal expansion. Operating stresses due to thermal and mechanical loads were also calculated. The accuracy of the model was verified by material data published in the …


A Study Of The Effect Of Flexibility On Manufacturing Performance, Prashanth B. Nagendra May 1990

A Study Of The Effect Of Flexibility On Manufacturing Performance, Prashanth B. Nagendra

Theses

Manufacturing flexibility has been a major topic of research in recent years. Researchers and managers are concerned about the role of flexibility in manufacturing performance. The strategic and economic impact of flexibility is of vital importance for managers in today's competitive industry.

This thesis initially provides an in-depth.perception of the prior research conducted in the area of manufacturing flexibility. Manufacturing flexibility, in this study, has been classified into four major types. Simple definitions and operational measures are provided for each of these primary types. The different factors effecting these flexibilities are identified. A new concept called the Cause-Effect-Flexibility-Technology diagrams based …


Development Of Air-Break Circuit Breaker, Ravi Kanth Korrapati May 1990

Development Of Air-Break Circuit Breaker, Ravi Kanth Korrapati

Theses

This thesis describes the development of an Air-Break circuit breaker, for Heinemann Electric Co., New Jersey, using I-DEAS CAD software. The physical properties obtained from the software, for the components of the armature assembly and the contact arm and the carriage, are used in determining the initial forces on a helical delay spring and in calculating accelerations of links in the trip mechanism. The trip mechanism is a four-bar mechanism with a spring as a coupler. Two second order differential equations define the motion of its links, the contact arm and the carriage. A time history of the links is …


A Study Of Methane Gas Production On Anaerobic Digestion System, Seng-Fung Su May 1990

A Study Of Methane Gas Production On Anaerobic Digestion System, Seng-Fung Su

Theses

The anaerobic sludge digestion process is not a recent development. At least 100 years ago in France,Louis H. Mouras designed and constructed fermenters to liquefy the sludge obtained from domestic wastes.

Since the turn of the century, the anaerobic fermentation process has been used extensively in the treatment of waste-water solids.

The necessity of preventing pollution of water resource, as a consequence of the rapid increase in human waste, demands adequate treatment of liquid wastes from domestic and industrial sources. For this purpose, the anaerobic digestion process can play an important role as a method for stabilizing and eliminating wastes …


The History Of The Trinity Highway: A Study In Transportation Dynamics, Richard Wilutus May 1990

The History Of The Trinity Highway: A Study In Transportation Dynamics, Richard Wilutus

Books and Other Publications

Although the primary focus of this thesis is a history of California 299--the Trinity Highway, I have studied the construction of that road in the context of the history of transportation between Weaverville and Humboldt Bay. The history of a transportation network is not only a history of connections between people and places but also, in this remote region, the vital link connecting wilderness with civilization.

Ever since the settlement of the Weaverville area in 1848, its residents have sought reliable transportation to Humboldt Bay's seaport and merchandise. During this period a road has connected these two places for less …


Pesticide And Water Management Alternatives To Mitigate Potential Ground-Water Contamination For Selected Counties In Utah, Majid Ehteshami, Antonio M. Requena, Richard C. Peralta, Howard M. Deer, Robert W. Hill, Ahmad Yar Ranjha May 1990

Pesticide And Water Management Alternatives To Mitigate Potential Ground-Water Contamination For Selected Counties In Utah, Majid Ehteshami, Antonio M. Requena, Richard C. Peralta, Howard M. Deer, Robert W. Hill, Ahmad Yar Ranjha

Civil and Environmental Engineering Faculty Publications

Production of adequate supplies of food and fiber currently requires that pesticides be used to limit crop losses from insects, pathogens, weeds and other pests. Although pesticides are necessary in today's agriculture, they can be a serious problem if they reach and contaminate ground water, especially in places where drinking water needs are supplied from ground water. The relative reduction of potential ground-water contamination due to agricultural use of pesticides was analyzed for particular sites in Utah. The potential reduction of pesticides in ground water was considered by utilizing alternative irrigation systems, water management practices and pesticides. A one-dimensional simulation …