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Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson Mar 2000

Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson

Theses and Dissertations

In this work, genetic algorithms (GAs) were used to help interpret tracer breakthrough curves from partitioning interwell tracer tests (PITTs) conducted at Hill AFB, Utah by researchers from the University of Florida. Two transport models were developed to simulate tracer transport in the test cells. One model assumed the cell consisted of multiple layers, and that transport in each layer could he described by the one-dimensional advective/dispersive equation. The second model also assumed multiple layers, and modeled transport in the individual layers as advective transport through 100 tubes. Transport times were represented by a stochastic (lognormal) distribution. The model solutions …


Inhibition Of N,N'-O-Phenylen-Bis(3-Methoxysalicylidenimine) On Copper In Halide Solutions, Hou-Yi Ma, Shen-Hao Chen, Zhen-Lan Quan, Lin Niu, Shu-Lan Li Feb 2000

Inhibition Of N,N'-O-Phenylen-Bis(3-Methoxysalicylidenimine) On Copper In Halide Solutions, Hou-Yi Ma, Shen-Hao Chen, Zhen-Lan Quan, Lin Niu, Shu-Lan Li

Journal of Electrochemistry

Inhibition of N,N'-o-phenylen-bis(3-methoxysalicylidenimine) (V-o-Ph-V) on corrosion and anodic disslution of copper in neutral NaCl and NaBr solutions was investigated in terms of potentiostatic steady-state polarization and A.C. impedance techniques. The inhibition mechanism of V-o-Ph-V to copper corrosion was interpreted in detail by comparing the electrochemical behaviors of copper in halide solutions with or without V-o-Ph-V. Besides, the inhibition effect of self-assembled V-o-Ph-V film on copper corrosion in NaCl was also studied.


Electrochemical Characterization Of Ir-Ta-Ti Metal Oxide Coated Titanium Anodes, Ting-Yong Wang, Li-Kun Xu, Guang-Zhang Chen Feb 2000

Electrochemical Characterization Of Ir-Ta-Ti Metal Oxide Coated Titanium Anodes, Ting-Yong Wang, Li-Kun Xu, Guang-Zhang Chen

Journal of Electrochemistry

Ir-Ta-Ti metal oxide coated titanium anodes of variable composition were prepared by thermal decomposition. Their micro morphorogies and electrochemical properties were characterized by scanning electron microscope, open circuit potential, cyclic voltammetry, consumption rate measurements and accelerated life test. The SEM results indicated that all coatings were of a porous and cracked-mud microstructure influenced greatly by the composition of coatings. The electrochemical measurements showed that the Ir-Ta-Ti ternary oxide-coated anodes exhibited excellent electrochemical activity and electrochemical stability in both acidic media and seawater which were affected by the composition and microstructure of the coatings. Owing to good corrosion resistance and low …


Reactor And Method For Solid Phase Peptide Synthesis, Nicholas Stepanluk, Keith Tomazi, Michael C. Stapleton Feb 2000

Reactor And Method For Solid Phase Peptide Synthesis, Nicholas Stepanluk, Keith Tomazi, Michael C. Stapleton

Chemical and Biochemical Engineering Faculty Research & Creative Works

A solid phase peptide synthesis reactor system and method of operating the reactor are provided. The reactor system includes a basket rotatable about an axis within a housing and a receiver which delivers fluid to; and collects fluid from; the housing. The basket has a perforate side wall against which a resin cake for the peptide synthesis formed. The reactor and receiver form a loop or circuit through which solutions are circulated. The circulation of the solutions prevents the reactor from flooding so that the basket Will not be submerged in solution and allows for the use of less liquid. …


Final Environmental Impact Statement - Iron Point Exploraton License - Iron Point Coal Lease Tract - Elk Creek Coal Lease Tract, Volume 2, United States Department Of Agriculture -- Forest Service, United States Department Of The Interior -- Bureau Of Land Management Feb 2000

Final Environmental Impact Statement - Iron Point Exploraton License - Iron Point Coal Lease Tract - Elk Creek Coal Lease Tract, Volume 2, United States Department Of Agriculture -- Forest Service, United States Department Of The Interior -- Bureau Of Land Management

Environmental Assessments (CO)

This appendix documents BLM and Forest Service activities to involve and consult with other government agencies and the public in the preparation of the Final EIS for the potential leasing of the Iron Point and Elk Creek Coal lease tracts, as well as the issuance of a coal exploration license for an area within and surrounding the Iron Point Coal lease Tract.


Multilevel Coded Modulation For Unequal Error Protection And Multistage Decoding—Part I: Symmetric Constellations, Robert H. Morelos-Zaragoza, Marc P. C. Fossorier, Shu Lin, Hideki Imai Feb 2000

Multilevel Coded Modulation For Unequal Error Protection And Multistage Decoding—Part I: Symmetric Constellations, Robert H. Morelos-Zaragoza, Marc P. C. Fossorier, Shu Lin, Hideki Imai

Faculty Publications

In this paper, theoretical upper bounds and computer simulation results on the error performance of multilevel block coded modulations for unequal error protection (UEP) and multistage decoding are presented. It is shown that nonstandard signal set partitionings and multistage decoding provide excellent UEP capabilities beyond those achievable with conventional coded modulation. The coding scheme is designed in such a way that the most important information bits have a lower error rate than other information bits. The large effective error coefficients, normally associated with standard mapping by set partitioning, are reduced by considering nonstandard partitionings of the underlying signal set. The …


Utilization Of Slag And Dust Generated From Iron And Steel Industry In Egypt, Yasser Sayed Korany Feb 2000

Utilization Of Slag And Dust Generated From Iron And Steel Industry In Egypt, Yasser Sayed Korany

Archived Theses and Dissertations

This thesis presents proposed environmentally friendly construction materials by utilizing slags and dust generated from steel industry in Egypt. Electrical Arc Furnace (EAF) dust is suggested to be used as an alternative to the conventional pigments for mortars and as a chemical resistance agent too. While air-cooled Blast Furnace (BF) slag, Basic Oxygen-converter Furnace (BOF) slag, and EAF slag are proposed to replace fine minerals in preparing cement floor hardeners and screed mortars for new and existing concrete floors. Furthermore, all slag types are also proposed to replace coarse aggregates in producing cement masonry units and paving stone interlocks. The …


Bs News Feb 2000

Bs News

Building Services Engineering

No abstract provided.


Collaborative Distance Education In Power Engineering, Anil Pahwa, Shelli K. Starrett, Kraig J. Olejniczak, S. D. Sudhoff, Mariesa Crow Feb 2000

Collaborative Distance Education In Power Engineering, Anil Pahwa, Shelli K. Starrett, Kraig J. Olejniczak, S. D. Sudhoff, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a perspective on offering "shared-courses," or courses simultaneously offered at two or more universities via various distance educational frameworks. Over a three year duration, two senior/graduate level courses were jointly developed and offered to the students at the University of Missouri--Rolla, the University of Arkansas, Kansas State University, and Purdue University. This paper discusses the various distance educational technologies including two-way audio/visual via ISDN line, video-tapes, and web-based conferencing. Both instructor and student reactions to these mediums are included. Pedagogical methods appropriate for these mediums are outlined. The paper concludes with recommendations and strategies for engineering institutions …


Development And Application Of Dynamic Models For Predicting Transit Arrival Times, Yuqing Ding Jan 2000

Development And Application Of Dynamic Models For Predicting Transit Arrival Times, Yuqing Ding

Dissertations

Stochastic variations in traffic conditions and ridership often have a negative impact in transit operations resulting in the deterioration of schedule/headway adherence and lengthening of passenger wait times. Providing accurate information on transit vehicle arrival times is critical to reduce the negative impacts on transit users. In this study, models for dynamically predicting transit arrival times in urban settings are developed, including a basic model, a Kalman filtering model, link-based and stop-based artificial neural networks (ANNs) and Neural/Dynamic (ND) models. The reliability of these models is assessed by enhancing the microscopic simulation program CORSIM which can calculate bus dwell and …


Multi-User Detection For Multi-Rate Ds/Cdma Systems, Jinwen Ma Jan 2000

Multi-User Detection For Multi-Rate Ds/Cdma Systems, Jinwen Ma

Dissertations

Wireless cellular communication is witnessing a rapid growth in market, technology and range of services. Current and future demands for wireless communication services motivate the need for handling multi-media traffic types. In a multimedia communication system, users with different and even time-varying rates and quality of services (QoS) requirements, such as voice, image and data, must be accommodated. The use of Spread Spectrum modulation with Code Division Multiple Access (CDMA) technology is an attractive approach for economical spectrally efficient and high quality cellular and personal communication services. This dissertation explores the technologies of applying different interference cancellation techniques to multi-rate …


Finite Fraction Method For Tracking Desinfection By-Product Precursors In Water Treatment, Doanh Van Jan 2000

Finite Fraction Method For Tracking Desinfection By-Product Precursors In Water Treatment, Doanh Van

Dissertations

Dissolved Organic Matter (DOM) has been the subject of recent regulatory activities and agenda. Among them are the Infonnation Collection Rule (ICR), the Disinfectants/Disinfection By-Product Rule (D/DBPR) and the Interim Enhanced Surface Water Treatment Rule (ESWTR). Both the latter two have provisions to limit the formation of disinfection by-products (DBP) by controlling reactivity and removal of DOM or both. Brief regulatory review of these rules was given.

Although the topic of DBP formation potential and DBP precursor removal have been studied by many researchers since Rooks (1974), the efficacy of methods that have been developed to date has been handicapped …


Data Hiding In Multimedia - Theory And Applications, Mahalingam Ramkumar Jan 2000

Data Hiding In Multimedia - Theory And Applications, Mahalingam Ramkumar

Dissertations

Multimedia data hiding or steganography is a means of communication using subliminal channels. The resource for the subliminal communication scheme is the distortion of the original content that can be tolerated. This thesis addresses two main issues of steganographic communication schemes:

1. How does one maximize the distortion introduced without affecting fidelity of the content?

2. How does one efficiently utilize the resource (the distortion introduced) for communicating as many bits of information as possible? In other words, what is a good signaling strategy for the subliminal communication scheme?

Close to optimal solutions for both issues are analyzed. Many techniques …


A Study Of Sound Attenuation Using Sonic Energy Focussed At An Artificial Soil Fracture, Minhaz Bootwala Jan 2000

A Study Of Sound Attenuation Using Sonic Energy Focussed At An Artificial Soil Fracture, Minhaz Bootwala

Theses

Several laws have been passed over the past two decades to control contamination and to remediate already existing contaminated sites. There are a large number of these sites and several ex-situ and in-situ techniques have been developed to decontaminate these sites. These techniques can be quite expensive, especially the ex-situ clean-up operations, and there has always been a need for cheap, quick remediation methods.

This study investigates the attenuation of sound used in the in situ remediation technique coupling Sonic Energy with Pneumatic Fracturing and Vapor Extraction. Preliminary attenuation studies were performed in the laboratory with a microphone made at …


Editing Mpeg2 Video In Compressed Domain, Ren Egawa Jan 2000

Editing Mpeg2 Video In Compressed Domain, Ren Egawa

Theses

As MPEG2 becomes the heart of most digital video applications, the need to edit an MPEG2 bitstream video in compressed domain has increased. To realize this need, two major technical issues must be resolved: decoder buffer and segment extraction.

In the decoder buffer issue, the edited stream must ensure that the buffer would not overflow or underfiow as the result of the editing. This thesis invented a mathematical model that could describe the editing task and predict the editing effect on the buffer. Based on this model, the thesis then built a method to edit a stream safely. This method …


Measurement Of Microcarrier Weighted Floc Using The Environmental Electron Microscope, Viriya Vithayaveroj Jan 2000

Measurement Of Microcarrier Weighted Floc Using The Environmental Electron Microscope, Viriya Vithayaveroj

Theses

Utilizing the concept of coagulation in conjunction with the sediment enhancement by microcarrier, the microcarrier process has been demonstrated in a laboratory investigation as an effective and economic operation in removing colloidal particles in an aquatic system. The microcarrier, an inert aluminum silicate particulate (Ottawa Sand) of 53 to 75 micrometers in diameter was used in this study. The interaction between the flocs and the microcarriers plays an important role in the mixing process. The principal objective of this study is to examine the structural interaction between the flocs and the microcarrier.

The study was designed into two stages, the …


Ultra High Density Storage Media And Method Thereof, Ravi F. Saraf Jan 2000

Ultra High Density Storage Media And Method Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A storage media for storing information having a substrate. The substrate has an upper surface and a molecular weight greater than 5,000. Preferably the material is a polymer. The material has a plurality of piles of molecular chains in selected areas formed by pushing the molecular chains of the material on its upper surface to the selected area mechanically with a mechanical tool. The piles represent written information. The mechanical tool is preferably an atomic force microscope. Another aspect of the present invention is a method for storing information having the steps of selecting a material substrate having an upper …


Investigation Of Tantalum Silicon Oxide As An Attenuated Phase Shift Masking Material For 157nm Lithography, Matthew Malley Jan 2000

Investigation Of Tantalum Silicon Oxide As An Attenuated Phase Shift Masking Material For 157nm Lithography, Matthew Malley

Journal of the Microelectronic Engineering Conference

As the microelectronics industry trends toward 157nm lithography and device geometries shrink below O.1μm, it seems more than likely that phase shift masking will be necessary as a means of optical enhancement. The attenuated phase shift mask is an attractive tool by which lithographers hope to push their art to its limits. However, potential niaterials for use as the attenuating film at wavelengths as low as 157nm have yet to be determined. There are several requirements that must be met by a material before it will be considered seriously for use on attenuating phase shift masks. One material …


Winter/Spring 2001, 90.9 Wmpg Fm Jan 2000

Winter/Spring 2001, 90.9 Wmpg Fm

WMPG Program Guides

Newspaper format.


Summer 2000, 90.9 Wmpg Fm Jan 2000

Summer 2000, 90.9 Wmpg Fm

WMPG Program Guides

No abstract provided.


Winter/Spring 2000, 90.9 Wmpg Fm Jan 2000

Winter/Spring 2000, 90.9 Wmpg Fm

WMPG Program Guides

Newspaper format


Fall/Winter 2000, Wmpg 90.9 Fm Jan 2000

Fall/Winter 2000, Wmpg 90.9 Fm

WMPG Program Guides

WMPG program guide for Fall/Winter 2000

Includes notes from Program Director, information on shows and events, and schedule.


Use Of The Generalized Integral Transform Method For Solving Equations Of Solute Transport In Porous Media, Chongxuan Liu, Jim E. Szecsody, John M. Zachara, William P. Ball Jan 2000

Use Of The Generalized Integral Transform Method For Solving Equations Of Solute Transport In Porous Media, Chongxuan Liu, Jim E. Szecsody, John M. Zachara, William P. Ball

United States Department of Energy: Publications

The generalized integral transform technique (GITT) is applied to solve the one-dimensional advection-dispersion equation (ADE) in heterogeneous porous media coupled with either linear or nonlinear sorption and decay. When both sorption and decay are linear, analytical solutions are obtained using the GITT for one-dimensional ADEs with spatially and temporally variable flow and dispersion coefficient and arbitrary initial and boundary conditions. When either sorption or decay is nonlinear the solutions to ADEs with the GITT are hybrid analytical-numerical. In both linear and nonlinear cases, the forward and inverse integral transforms for the problems described in the paper are apparent and straightforward. …


On The Error Performance Of 8-Vsb Tcm Decoder For Atsc Terrestrial Broadcasting Of Digital Television, Dojun Rhee, Robert H. Morelos-Zaragoza Jan 2000

On The Error Performance Of 8-Vsb Tcm Decoder For Atsc Terrestrial Broadcasting Of Digital Television, Dojun Rhee, Robert H. Morelos-Zaragoza

Faculty Publications

The error performance of various 8-VSB TCM decoders for reception of terrestrial digital television is analyzed. In previous work, 8-state TCM decoders were proposed and implemented for terrestrial broadcasting of digital television. In this paper, the performance of a 16-state TCM decoder is analyzed and simulated. It is shown that not only a 16-state TCM decoder outperforms one with 8-states, but it also has much smaller error coefficients.


Ultrasonic Testing For Compacted Clayey Soils, Nazli Yesiller, Gokhan Inci, Carol J. Miller Jan 2000

Ultrasonic Testing For Compacted Clayey Soils, Nazli Yesiller, Gokhan Inci, Carol J. Miller

Civil and Environmental Engineering

In this study, tests were conducted to investigate the use of ultrasonic methods to determine compaction characteristics of clayey soils. In particular, through-transmission test method was used to determine P-wave velocities in compacted clayey soils. Effects of soil type and compaction conditions on velocity were investigated. Tests were conducted on three soils that had low, medium, and high plasticity. Soils were prepared at water contents ranging from dry to wet of optimum using standard and modified compaction efforts. It was observed that velocity increased with increasing compactive effort and decreasing plasticity and clay content. Moreover, the variation of ultrasonic velocity …


Development Of Vaccines For Prevention Of Botulism, Michael P. Byrne, Leonard A. Smith Jan 2000

Development Of Vaccines For Prevention Of Botulism, Michael P. Byrne, Leonard A. Smith

United States Army: Publications

Botulism is a potentially lethal disease caused by one of seven homologous neurotoxic proteins usually produced by the bacterium, Clostridium botulinum. This neuromuscular disorder occurs through an exquisite series of molecular events, ultimately ending with the arrest of acetylcholine release and hence, flaccid paralysis. The development of vaccines that protect against botulism dates back to the 1940s. Currently, a pentavalent vaccine that protects against BoNT serotypes A-E and a separate monovalent vaccine that protects against BoNT serotype F are available as Investigational New Drugs. However, due to the numerous shortcomings associated with the toxoid vaccines, several groups have efforts …


Mineral Transformation Associated With The Microbial Reduction Of Magnetite, Hailiang Dong, James K. Fredrickson, David W. Kennedy, John M. Zachara, Ravi K. Kukkadapu, Tullis C. Onstott Jan 2000

Mineral Transformation Associated With The Microbial Reduction Of Magnetite, Hailiang Dong, James K. Fredrickson, David W. Kennedy, John M. Zachara, Ravi K. Kukkadapu, Tullis C. Onstott

United States Department of Energy: Publications

Although dissimilatory iron reducing bacteria (DIRB) are capable of reducing a number of metals in oxides and soluble forms, the factors controlling the raterextent of magnetite reduction and the nature of the mineral products resulting from magnetite reduction are not well understood. This study was carried out to investigate mechanisms and biogeochemical processes occurring during magnetite reduction by the DIRB, Shewanella putrefaciens strains CN32 and MR-1. Reduction experiments were performed with biogenic and synthetic magnetite in well-defined solutions. Biogenic magnetite was generated via microbial reduction of hydrous ferric oxide (HFO). Biogenic magnetite in solutions buffered with either bicarbonate (HCO3 …


Reduction Of U(Vi) In Goethite (Α-Feooh) Suspensions By A Dissimilatory Metal-Reducing Bacterium, James K. Fredrickson, John M. Zachara, David Kennedy, Martine Duff, Yuri Gorby, Shu-Mei Li, Kenneth Krupka Jan 2000

Reduction Of U(Vi) In Goethite (Α-Feooh) Suspensions By A Dissimilatory Metal-Reducing Bacterium, James K. Fredrickson, John M. Zachara, David Kennedy, Martine Duff, Yuri Gorby, Shu-Mei Li, Kenneth Krupka

United States Department of Energy: Publications

Dissimilatory metal-reducing bacteria (DMRB) can utilize Fe(III) associated with aqueous complexes or solid phases, such as oxide and oxyhydroxide minerals, as a terminal electron acceptor coupled to the oxidation of H2 or organic substrates. These bacteria are also capable of reducing other metal ions including Mn(IV), Cr(VI), and U(VI), a process that has a pronounced effect on their solubility and overall geochemical behavior. In spite of considerable study on an individual basis, the biogeochemical behavior of multiple metals subject to microbial reduction is poorly understood. To probe these complex processes, the reduction of U(VI) by the subsurface bacterium, Shewanella …


The Effect Of Ozone On Below-Ground Carbon Allocation In Wheat, J. K. Mccrady, C.P. Andersen Jan 2000

The Effect Of Ozone On Below-Ground Carbon Allocation In Wheat, J. K. Mccrady, C.P. Andersen

United States Environmental Protection Agency: Publications

Short-term 14CO2 pulse and chase experiments were conducted in order to investigate the effect of ozone on below-ground carbon allocation in spring wheat seedlings (Triticum aestivum L. `ANZA'). Wheat seedlings were grown in a sand-hydroponic system and exposed to either high ozone (38-40 ppm-h) or low ozone (23-31 ppm-h) for 21 days in a series of replicated experiments. Following the ozone exposures, the plants were pulsed with 14CO2 and allocation of 14C-labeled photosynthate was measured in the plant and growth media. Soluble root exudates were measured, without disturbing the plant roots, 24 h after …


Evaporation Reduction Potential In An Undisturbed Soil Irrigated With Surface Drip And Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman Jan 2000

Evaporation Reduction Potential In An Undisturbed Soil Irrigated With Surface Drip And Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman

Biosystems and Agricultural Engineering Faculty Publications

The efficiency of drip irrigation is highly dependent on evaporation losses occurring from the constantly saturated soil beneath emitters. Advent of subsurface drip irrigation is in part an approach to curb this inefficiency. An irrigation method, Sand Tube Irrigation (STI), is proposed to increase the efficiency of “Normal” surface applied drip Irrigation (NI method) on permanent tree crops without the need for burying the irrigation tubing. The sand tube consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was constructed in the laboratory and instrumented to directly measure temporal evaporation …