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Shoreline Change Modeling As A Tool In Coastal Environmental Management, Jorge Espinoza Amaguana Jul 1998

Shoreline Change Modeling As A Tool In Coastal Environmental Management, Jorge Espinoza Amaguana

Civil & Environmental Engineering Theses & Dissertations

The one-line numerical model GENESIS has been calibrated to evaluate its performance as a tool in providing insights into the physical components to manage the coastal environment. To calibrate the model, physical environmental data, literature research, and computer modeling methodologies were utilized in addressing the objectives of this thesis. The model was applied at three beaches of the Virginia Beach City with different man-made structures by using the actual field wave data for wave year J 997. Waves are the main environmental component affecting the coastal system; however, additional environmental data and the best engineering decision were used as model …


Use Of Dissolved Oxygen Concentration Probes In Biological Wastewater Treatment Plants, S Manyele Jun 1998

Use Of Dissolved Oxygen Concentration Probes In Biological Wastewater Treatment Plants, S Manyele

Tanzania Journal of Engineering and Technology (TJET)

A study on use Of dissolved oxygen probes (DOP) for measurement Of oxygen concentration in warer and wastewater treatment is presented. The principles Of operation, design considerations and selection criteria for Two types of probes, viz. galvanic and polarographic, are discussed Use of polarographic probes in n rhree-phase fluidized bed bioreactor and in laboratory experiments is presented and discussed. The effect of airflow rate and treatment time on dissolved oxygen concentration was found to be significant. It was found that polarographic probes are important equipment in determining the pollution of the industrial effluents. Finally, the use of the DOC probes …


Sustainability And Resource Assessment: A Case Study Of Soil Resources In The United States, Dana L. Hoag, Jennie S. Hughes Popp, D. Eric Hyatt Jun 1998

Sustainability And Resource Assessment: A Case Study Of Soil Resources In The United States, Dana L. Hoag, Jennie S. Hughes Popp, D. Eric Hyatt

United States Environmental Protection Agency: Publications

Assessment of environmental condition is critical to wise management and policy decisions. However, for some concerns such as sustainability, it is difficult to assess environmental condition because it involves disparate social objectives and an understanding of complex ecological systems. Here, a general framework is proposed to examine sustainability of environmental resources in objective, measurable ways. By using soil quality as an example, sustainability research is taken beyond theory and into application.
Sustainability depends on the quality of resource endowment. Endowment of a natural resource can be modeled as an index of quality to assess the degree of sustainable management. This …


Psychophysically Derived Work Frequencies For Manual Pouring Operations In The Foundry, Sadat Karim Jun 1998

Psychophysically Derived Work Frequencies For Manual Pouring Operations In The Foundry, Sadat Karim

Masters Theses

This paper presents a study on a combination lift and carrying task and was designed to simulate a metal pouring operation commonly found in foundries. Two laboratory experiments were conducted. The first experiment was designed to study the effects of two different mold heights (0.6096 m. and 0.4572 m.) and two carrying distances (1.2192 m. and 4.572 m.) on physiological response variables and on subjects' rating of perceived exertion while performing a simulated pouring operation at a documented foundry frequency. The second experiment was designed to determine maximum acceptable task frequencies (MAF) for males performing a simulated pouring operation at …


Data-Driven Homologue Matching For Chromosome Identification, R. Joe Stanley, James M. Keller, Paul D. Gader, Charles William Caldwell Jun 1998

Data-Driven Homologue Matching For Chromosome Identification, R. Joe Stanley, James M. Keller, Paul D. Gader, Charles William Caldwell

Electrical and Computer Engineering Faculty Research & Creative Works

Karyotyping involves the visualization and classification of chromosomes into standard classes. In "normal" human metaphase spreads, chromosomes occur in homologous pairs for the autosomal classes 1-22, and X chromosome for females. Many existing approaches for performing automated human chromosome image analysis presuppose cell normalcy, containing 46 chromosomes within a metaphase spread with two chromosomes per class. This is an acceptable assumption for routine automated chromosome image analysis. However, many genetic abnormalities are directly linked to structural or numerical aberrations of chromosomes within the metaphase spread. Thus, two chromosomes per class cannot be assumed for anomaly analysis. This paper presents the …


Optimizing Conjunctive Water Use For Sustainable Production: Tools For The Management Spectrum, Richard C. Peralta, Shengjun J. Wu, H. J. Morel-Seytoux, Fernando Chanduvi Jun 1998

Optimizing Conjunctive Water Use For Sustainable Production: Tools For The Management Spectrum, Richard C. Peralta, Shengjun J. Wu, H. J. Morel-Seytoux, Fernando Chanduvi

Civil and Environmental Engineering Faculty Publications

Making best use of water resources requires coordinating use of groundwater and surface waters--conjunctive use. Conjunctive water management is important on the regional (watershed or aquifer), water district and field scales. Goals might differ for the different administrative levels. A regionally optimal water management strategy is not necessarily optimal for water district managers and individual farmers. Interactions between levels are affected by laws, regulations, traditions and public pressure. To help each organizational level develop water management strategies that best achieve its goals, computer simulation/optimization (S/O) models are useful. Such S/O models couple water flow and transport simulation techniques with formal …


Removal Of Volatile Organic Compound (Voc) Vapors In Biotrickling Filters : Process Modeling And Validation With Chlorinated Aromatic Compounds, Christos J. Mpanias May 1998

Removal Of Volatile Organic Compound (Voc) Vapors In Biotrickling Filters : Process Modeling And Validation With Chlorinated Aromatic Compounds, Christos J. Mpanias

Dissertations

This study dealt with the removal of vapors of volatile organic compounds from airstreams in biotrickling filters (BTFs). A detailed general model was developed for describing the process under steady-state conditions. The model accounts for mass transfer between phases (air, liquid, biofilm) and biodegradation of pollutants in the biofilm. It also accounts for potential kinetic interactions among pollutants as well as potential process limitations by oxygen availability.

The general model was experimentally validated using mono-chlorobenzene (m-CB) and ortho-dichlorobenzene (o-DCB) as model compounds either alone or in mixture with each other. Before BTF experiments were undertaken, a systematic kinetic study was …


Modelling Of In-Situ Bioremediation With Emphasis On Inhibitory Kinetics And Biomass Growth, Dilip Kumar Mandal May 1998

Modelling Of In-Situ Bioremediation With Emphasis On Inhibitory Kinetics And Biomass Growth, Dilip Kumar Mandal

Dissertations

This thesis was motivated by the need for better engineering tools to predict the extent of contaminant plume migration in the saturated zone. The principal result was a mathematical model analogous to a catalytic packed-bed reactor, in which the subsurface was considered to be composed (conceptually) of soil aggregates (the "catalyst" particles, in which biodegradation, diffusion, and sorption take place), and a mobile phase (groundwater) passing around the aggregates, in which convection, axial diffusion, and mass transfer from the aggregates take place.

The modelling emphasis was on a more detailed exposition of the biokinetics of the system (including an inhibitory …


Mathematical Model Of Human Sit-To-Stand And Stand-To-Sit Motion Analysis, Jayeshkumar Gandhi May 1998

Mathematical Model Of Human Sit-To-Stand And Stand-To-Sit Motion Analysis, Jayeshkumar Gandhi

Theses

In designing a device for an amputee, it is important to find those underlying principles which determine the normal human sit-to-stand task. For this purpose we have developed a mathematical model of human sit-to-stand movement, which it is possible to predict the minimum mechanical energy consumption to move from the sit-to-stand position.

To the best of author's knowledge, this thesis represents the first time that the periodic motion of stand-to-sit and sit-to-stand movements have been mathematically modeled by a simple mechanical system. A complex model, such as the one used by Seireg and Arvikar (1973) [1] that contained 31 muscles …


Investigation Of Pathophysiologic Trends In Caucasian And Afro-American Hypertensives By Means Of Heart Rate Variability Recording During Upright Tilt-Table Testing, Jose F. Torrealba May 1998

Investigation Of Pathophysiologic Trends In Caucasian And Afro-American Hypertensives By Means Of Heart Rate Variability Recording During Upright Tilt-Table Testing, Jose F. Torrealba

Theses

The incidence of hypertension is more prevalent among the Afro-American population than the Caucasians and there is not a satisfactory explanation for this discrepancy.

Heart Rate Variability (HRV) has been demonstrated to reflect the relative activities of the sympathetic (SMP) and parasympathetic (PSMP) divisions of the autonomic nervous system (ANS).

This study consisted in comparing the HRV, as well as the blood pressure (BP) of four different groups during up-right tilt table testing. The subjects were grouped by age, gender, race and health condition. Analysis in time and frequency domain was applied to the data. In the frequency domain, the …


Quantitative Estimation Of Heparin Content On Biological Pericadium Tissue Using In Vitro Anti-Factor Xa Assay, Jean-Claude Simeon May 1998

Quantitative Estimation Of Heparin Content On Biological Pericadium Tissue Using In Vitro Anti-Factor Xa Assay, Jean-Claude Simeon

Theses

Shelhigh Inc. (Millburn, NJ) has developed a new heparin binding technique to biological tissues. The technique seems to bind heparin to tissues in a more permanent fashion. Shelhigh's heparinized biological tissues are intended for use in long term implants. This investigation was undertaken to assess whether heparin leaching is prevalent when tissues are quarantine for long shelflife at room temperature, whether tissues maintained thromboresistance properties when in contact with plasma and to estimate heparin content of the tissues.

The study used anti-factor Xa assaying methods: clotting time and chromogenic factor Xa sensitive substrate in order to fulfill the aforementioned objectives. …


New Esr-Electrochemical Cell Designs For Coaxial Microwave Cavity, Lin Zhuang, Jun-Tao Lu May 1998

New Esr-Electrochemical Cell Designs For Coaxial Microwave Cavity, Lin Zhuang, Jun-Tao Lu

Journal of Electrochemistry

New cell designs for simultaneous electrochemical (EC) and electron spin resonance (ESR) measurements are reported for coaxial microwave cavity. Adjustable shieldings are introduced so that the working electrode can be much shorter than the full height of the cavity. Besides the traditional helical electrode, the working electrode can be cylinders made from metal plates, metallic meshes or even composite materials. The counter electrode can be placed either inside or outside the cavity. These features make the new designs more flexible than that previously reported. With a nonperforated cylindrical electrode, this cell can be used to determine the standard potential and …


1998 - The Third Annual Symposium Of Student Scholars May 1998

1998 - The Third Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the Third Annual Symposium of Student Scholars, held on May 8th, 1998. Includes abstracts from the presentation and posters.


Remedial Action Plan For A Petroleum Hydrocarbon Release, Marty E. Murrietta May 1998

Remedial Action Plan For A Petroleum Hydrocarbon Release, Marty E. Murrietta

UNLV Theses, Dissertations, Professional Papers, and Capstones

This Remediation Action Plan (RAP) presents the methods and results of feasibility testing, the screening and selection of remedial options, preliminary conceptual design, methods, permitting requirements, recommendations and cleanup goals for on- and off-site remediation of petroleum hydrocarbon impacted soil and groundwater at an undisclosed site in Laughlin, Nevada. This site is an active convenience store and former retail fueling station. Plans are being made for the demolition of the fueling station and construction of a Factory Outlet Mall on the former refueling station site and surrounding properties to the south, west, and northwest. Remediation activities cannot significantly interfere with …


Characteristics And Performance Of R413a As An Alternative Refrigerant To R12, Waleed Mahmoud El-Nahas May 1998

Characteristics And Performance Of R413a As An Alternative Refrigerant To R12, Waleed Mahmoud El-Nahas

Archived Theses and Dissertations

No abstract provided.


Poseidon American Society Of Civil Engineers/Master Builders Rocky Mountain Regional Concrete Canoe Competition, William Spencer Guthrie May 1998

Poseidon American Society Of Civil Engineers/Master Builders Rocky Mountain Regional Concrete Canoe Competition, William Spencer Guthrie

Undergraduate Honors Capstone Projects

The concrete canoe team has been selected in behalf of the Utah State University Student Chapter of the American Society of Civil Engineers to prepare an entry for the 1998 ASCE Rocky Mountain Regional Concrete Canoe Competition. This event is co-sponsored by the American Society of Civil Engineers and Master Builders, Inc., and has become a tradition at annual ASCE regional conferences nationwide.


Parameter Estimation Using Artificial Neural Network And Genetic Algorithm For Free-Product Migration And Recovery, J. Morshed, Jagath J. Kaluarachchi May 1998

Parameter Estimation Using Artificial Neural Network And Genetic Algorithm For Free-Product Migration And Recovery, J. Morshed, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Artificial neural network (ANN) is considered to be a universal function approximator, and genetic algorithm (GA) is considered to be a robust optimization technique. As such, ANN regression analysis and ANN-GA optimization techniques can be used to perform inverse groundwater modeling for parameter estimation. In this manuscript the applicability of these two techniques in solving an inverse problem related to a light-hydrocarbon-contaminated site is assessed. The critical parameters to be evaluated are grain-size distribution index α and saturated hydraulic conductivity of water Ksw, since these parameters control free-product volume predictions and flow. A set of published data corresponding to a …


Multidirectional Ecg Coherent Optimal Timing Of Defibrillation Shocks, Abhijit R. Patwardhan, Fabio M. Leonelli Apr 1998

Multidirectional Ecg Coherent Optimal Timing Of Defibrillation Shocks, Abhijit R. Patwardhan, Fabio M. Leonelli

Biomedical Engineering Faculty Patents

A method for of delivering a defibrillation shock to a heart at an optimal time to stop ventricular fibrillation which involves obtaining an electrocardiogram of a heart in at least two directions, determining a time-coherency of the electrocardiogram based upon each of the at least two directions, and computing a tracking function from the time-coherency. An optimal time to apply a defibrillation shock to the heart is determined by locating a local maximum on the tracking function. The method utilizes spacia characteristics of the ventricular fibrillation. The method can be incorporated into implantable cardioverter defibrillators utilizing existing hardware technology.


Optimizing Separate Phase Light Hydrocarbon Recovery From Contaminated Unconfined Aquifers, G. S. Cooper, Richard C. Peralta, Jagath J. Kaluarachchi Apr 1998

Optimizing Separate Phase Light Hydrocarbon Recovery From Contaminated Unconfined Aquifers, G. S. Cooper, Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A modeling approach is presented that optimizes separate phase recovery of light non-aqueous phase liquids (LNAPL) for a single dual-extraction well in a homogeneous, isotropic unconfined aquifer. A simulation/regression/optimization (S/R/O) model is developed to predict, analyze, and optimize the oil recovery process. The approach combines detailed simulation, nonlinear regression, and optimization. The S/R/O model utilizes nonlinear regression equations describing system response to time-varying water pumping and oil skimming. Regression equations are developed for residual oil volume and free oil volume. The S/R/O model determines optimized time-varying (stepwise) pumping rates which minimize residual oil volume and maximize free oil recovery while …


Molecular Modelling Studies Of Acetylcholinesterase, Charilaos E. Linaras Apr 1998

Molecular Modelling Studies Of Acetylcholinesterase, Charilaos E. Linaras

Dissertations

The controversial role of electrostatic interactions in the process of steering of acetylcholine into the active site of acetylcholinesterases was investigated in this study. A novel methodology was implemented to simulate the process of recognition of acetylcholine by Torpedo Californica and both wild type and charge neutralized mutated Human AChE. The obtained results suggest the important role of coulombic interactions in the steering process. The steering process of selected irreversible AChE inhibitors was also simulated supporting the role of electrostatic interactions in the recognition process.

A novel methodology was also employed to model the covalent adducts of Torpedo Californica and …


Energy Efficient Resource Recovery Project, Daniel Panetta, Douglas Williams, Walter Bremer, Gary Karner, Harap Mallareddy, Margot Mcdonald, Samuel A. Vigil, Bailey Green, Henry Hammer, William J. Oswald, William Roley, Jr. Apr 1998

Energy Efficient Resource Recovery Project, Daniel Panetta, Douglas Williams, Walter Bremer, Gary Karner, Harap Mallareddy, Margot Mcdonald, Samuel A. Vigil, Bailey Green, Henry Hammer, William J. Oswald, William Roley, Jr.

Civil and Environmental Engineering

No abstract provided.


Material Evaluation By Pulsed Diode Laser Optoacoustics, Xiaodong Xu Apr 1998

Material Evaluation By Pulsed Diode Laser Optoacoustics, Xiaodong Xu

Electrical & Computer Engineering Theses & Dissertations

Pulsed diode laser optoacoustic diagnostics were carried out to characterize solid sample materials. The apparatus developed is compact, portable, cost-effective and therefore very promising for both industrial as well as laboratory applications. To our knowledge, this is the first time that optoacoustic characterization and measurement have been performed with a diode laser. The method was successfully applied to measure the thickness of a multilayer structure non-intrusively. Internal cracks of the material were detected by this technique.

A theory for optoacoustic signal generation, propagation and detection is given. A numerical analysis technique is developed to solve for the expected signal. In …


Thin-Layer Prestressed Composite Ferroelectric Driver And Sensor Characterization With Application To Separation Flow Control, Karla M. Mossi Apr 1998

Thin-Layer Prestressed Composite Ferroelectric Driver And Sensor Characterization With Application To Separation Flow Control, Karla M. Mossi

Mechanical & Aerospace Engineering Theses & Dissertations

Experiments were conducted in two different stages--general piezoelectric actuator characterization and flow separation control applications. The characterization of the piezoelectric devices was performed in several stages, due to the many variables that affect performance. The first stage of the characterization consisted of tests conducted on 13 different THUNDERTM (thin-layer composite unimorph ferroelectric driver and sensor) configurations. These configurations consisted of a combination of 1, 3, 5, 7, and 9 layers of 25μ thick aluminum as backing material, with and without a top layer of 25μ aluminum. All of these configurations used the same piezoelectric ceramic wafer (PZT-5A) with dimensions …


Parallel Implementation Of An Artificial Neural Network Integrated Feature And Architecture Selection Algorithm, Craig W. Rizzo Mar 1998

Parallel Implementation Of An Artificial Neural Network Integrated Feature And Architecture Selection Algorithm, Craig W. Rizzo

Theses and Dissertations

The selection of salient features and an appropriate hidden layer architecture contributes significantly to the performance of a neural network. A number of metrics and methodologies exist for estimating these parameters. This research builds on recent efforts to integrate feature and architecture selection for the multilayer perceptron. In the first stage of work a current algorithm is developed in a parallel environment, significantly improving its efficiency and utility. In the second stage, improvements to the algorithm are proposed. With regards to feature selection, a common random number (CRN) addition is proposed. Two new methods of architecture selection are examined, to …


A Municipal Landfill Cover With A Paper Sludge Barrier Layer, Carsten H. Floess, Warren A. Harris Iv, Horace K. Moo-Young Jr., Thomas F. Zimmie Mar 1998

A Municipal Landfill Cover With A Paper Sludge Barrier Layer, Carsten H. Floess, Warren A. Harris Iv, Horace K. Moo-Young Jr., Thomas F. Zimmie

International Conference on Case Histories in Geotechnical Engineering

The Corinth landfill closure project was the first in New York State to use paper sludge as alternative barrier layer material in a landfill cap. The use of paper mill sludge in the cap reduced cost relative to a conventional clay or geomembrane cap system. The beneficial reuse of the paper sludge also saved landfill space. To demonstrate the feasibility of using paper sludge as barrier layer material, extensive research was conducted to evaluate the physical properties of the sludge, primarily hydraulic conductivity. Centrifuge model tests were conducted to simulate infiltration through the cap over a 30 year period. Centrifuge …


A Particular Foundation Problem On A Waste Fill, F. Colleselli, M. Macoratti Mar 1998

A Particular Foundation Problem On A Waste Fill, F. Colleselli, M. Macoratti

International Conference on Case Histories in Geotechnical Engineering

The construction of a new aerobic water treatment system for polluted water in the ENJCHEM chemical plant at Mantova (N. Italy), emphasized a particular foundation problem; the complete treatment system, covering a surface area of 12000 m2, lies on a zone once used as a waste fill, 4-6 m deep and composed of various materials from industrial processing, with highly variable origins and poor resistance characteristics. The main structures are: steel tanks with fixed roofs, and gauge and settling tanks, of 30 and 26 m diameter respectively, each containing a 15-m water head, reinforced concrete sediment thickeners and …


From The Past To The Future Of Landfill Engineering Through Case Histories, R. Kerry Rowe Mar 1998

From The Past To The Future Of Landfill Engineering Through Case Histories, R. Kerry Rowe

International Conference on Case Histories in Geotechnical Engineering

The advances in landfill engineering are outlined based on a number of case histories illustrating past problems, hydraulic performance of clay liners, diffusive transport through liners, hydraulic containment and clogging of leachate collection systems. The importance of conventional geotechnical considerations (e.g. stability) will also be highlighted with reference to a number of cases. Finally, the recent advances in landfill operations are illustrated with respect to a modern landfill. It is concluded that, provided all key failure mechanisms are considered in the design, construction and operation of the facility, modern landfills should provide environmental protection both today and well into the …


Use Of Geofabrics For Controlling Landslides − Case Histories, Dipak Mukherjee, Satish Kumar Mar 1998

Use Of Geofabrics For Controlling Landslides − Case Histories, Dipak Mukherjee, Satish Kumar

International Conference on Case Histories in Geotechnical Engineering

Four case histories on erosion and rock fall control by the use of natural and synthetic geogrids are described. Each of the affected area was analysed and treated adopting different techniques of installation of geofabrics mantle as control measures which resulted in significant improvement of slope stability. Treatment also helped in maintaining ecological balance of the hills.


The Rationale For Negligible Risk Exemptions In The Telecommunications Act Of 1996: Cellular Phone And Personal Communication System Transmitters, Gregg H. Claycamp Mar 1998

The Rationale For Negligible Risk Exemptions In The Telecommunications Act Of 1996: Cellular Phone And Personal Communication System Transmitters, Gregg H. Claycamp

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

Dr. Claycamp explains the adequacy of current legislation and regulation.


How To Divide A Territory? A New Simple Differential Formalism For Optimization Of Set Functions, Hung T. Nguyen, Vladik Kreinovich Mar 1998

How To Divide A Territory? A New Simple Differential Formalism For Optimization Of Set Functions, Hung T. Nguyen, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical problems, we must optimize a set function, i.e., find a set A for which f(A) is maximum, where f is a function defined on the class of sets. Such problems appear in design, in image processing, in game theory, etc.

Most optimization problems can be solved (or at least simplified) by using the fact that small deviations from an optimal solution can only decrease the value of the objective function; as a result, some derivative must be equal to 0. This approach has been successfully used, e.g., for set functions in which the desired set A …