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Corrosion Protection Of Steel Using Nonanomalous Ni-Zn-P Coatings, Basker Veeraraghavan, Bala Haran, Swaminatha P. Kumaraguru, Branko N. Popov Jan 2003

Corrosion Protection Of Steel Using Nonanomalous Ni-Zn-P Coatings, Basker Veeraraghavan, Bala Haran, Swaminatha P. Kumaraguru, Branko N. Popov

Faculty Publications

A novel technique for obtaining nonanomalous Ni-Zn-P coatings with high Ni content (74 wt % as compared to 15-20 wt % in the conventional plating method) has been developed. These coatings show promise as a replacement for Cd in sacrificially protecting steel. Ni-Zn-P coatings were deposited using an electroless method from a solution containing NiSO4, complexing agent and ammonium chloride. Varying the concentration of ZnSO4 in the bath controls the final amount of Zn in the deposit. The Zn content in the coating was optimized based on the corrosion resistance of the final deposit. Coatings with 16.2 …


Development Of A Novel Electrochemical Method To Deposit High Corrosion Resistant Silicate Layers On Metal Substrates, Basker Veeraraghavan, Bala Haran, Dragan Slavkov, Swaminatha Prabhu, Branko N. Popov, Bob Heimann Jan 2003

Development Of A Novel Electrochemical Method To Deposit High Corrosion Resistant Silicate Layers On Metal Substrates, Basker Veeraraghavan, Bala Haran, Dragan Slavkov, Swaminatha Prabhu, Branko N. Popov, Bob Heimann

Faculty Publications

A novel method for electrodepositing silicates on metallic substrates from aqueous solutions has been developed. The technique is demonstrated by forming a passive film on galvanized steel. The silicate layer was deposited cathodically from a bath containing PQ Corporation N sodium silicate solution (3.22 weight ratio sodium silicate, 37.5% solution in water). A post-treatment drying process increased the Si content in the coating and improved the corrosion characteristics of the silicate layer. Deposition parameters like bath concentration and temperature have been optimized using corrosion characteristics and surface morphology of the final coating. Finally, stability studies show that the silicate coatings …


Antenna-Coupled Infrared Focal Plane Array, Francisco Javier Gonzalez Jan 2003

Antenna-Coupled Infrared Focal Plane Array, Francisco Javier Gonzalez

Retrospective Theses and Dissertations

In this dissertation a new type of infrared focal plan array (IR FPA) was investigated, consisting of antenna-coupled microbolometer fabricated using electron-beam lithography. Four different antenna designs were experimentally demonstrated at 10-micron wavelength: dipole, bowtie, square-spiral, and log-periodic. The main differences between these antenna types were their bandwidth, collection area, angular reception pattern, and polarization. To provide pixel collection areas commensurate with typical IR FPA requirements, two configurations were investigated: a two-dimensional serpentine interconnection of individual IR antennas, and a Fresnel-zone-plate (FZP) coupled to a single-element antenna. Optimum spacing conditions for the two-dimensional interconnect were developed. Increased sensitivity was demonstrated …


Public Street Surveillance: A Psychometric Study On The Perceived Social Risk, David J. Brooks Jan 2003

Public Street Surveillance: A Psychometric Study On The Perceived Social Risk, David J. Brooks

Theses: Doctorates and Masters

Public street surveillance, a domain of Closed Circuit Television (CCTV), has grown enormously and is becoming common place with increasing utilization in society as an all-purpose security tool. Previous authors (Ditton, 1999; Davies, 1998; Horne, 1998; Tomkins, 1998) have raised concern over social, civil and privacy issues, but there has been limited research to quantify these concerns. There are a number of core aspects that could relocate the risk perception and therefore, social support of public street surveillance. This study utilized the psychometric paradigm to quantitatively measure the social risk perception of public street surveillance. The psychometric paradigm is a …


Automatic Human Face Detection In Color Images, Son Lam Phung Jan 2003

Automatic Human Face Detection In Color Images, Son Lam Phung

Theses: Doctorates and Masters

Automatic human face detection in digital image has been an active area of research over the past decade. Among its numerous applications, face detection plays a key role in face recognition system for biometric personal identification, face tracking for intelligent human computer interface (HCI), and face segmentation for object-based video coding. Despite significant progress in the field in recent years, detecting human faces in unconstrained and complex images remains a challenging problem in computer vision. An automatic system that possesses a similar capability as the human vision system in detecting faces is still a far-reaching goal. This thesis focuses on …


Educating The Guess: Strategies, Concepts And Tools For The Fuzzy Front End Of Product Development, Antonie J. Jetter Jan 2003

Educating The Guess: Strategies, Concepts And Tools For The Fuzzy Front End Of Product Development, Antonie J. Jetter

Engineering and Technology Management Faculty Publications and Presentations

Many companies lack efficient management of the early phases of new product development (NPD) - the socalled fuzzy front end (FFE). Rather than on structured methods, decision makers rely on ?gut ?feel? or ?guessing?. In an attempt to ?educate the guess? this paper discusses the activities and challenges of the FFE, as well as strategies to manage them successfully. It then briefly presents traditional and recent approaches to front-end management support. Based on the identified strengths and weaknesses of existing front-end solutions, the framework of a new management support system for the FFE is presented. Conceptually, the system is based …


Under The Plastic: A Quantitative Look At Dvd Video Encoding And Its Impact On Video Modeling, Wu-Chi Feng, Jin Choi, Wu-Chang Feng, Jonathan Walpole Jan 2003

Under The Plastic: A Quantitative Look At Dvd Video Encoding And Its Impact On Video Modeling, Wu-Chi Feng, Jin Choi, Wu-Chang Feng, Jonathan Walpole

Computer Science Faculty Publications and Presentations

In this paper, we examine the DVD encoding process and the implications this process has video modeling and network traffic analysis. We have assembled a system that allows us to extract the video data from the DVDs as they were encoded for distribution. Analyzing the resulting video trace data, we describe how DVD encodings have evolved over time. In addition, our findings show that the underlying video content is fundamentally different than those produced by basic consumer video capture boards. We demonstrate how this affects current video modeling proposals and their affect on network traffic characterization. This research is based …


The Zen Of The Web, Jeff Heflin, Michael N. Huhns Jan 2003

The Zen Of The Web, Jeff Heflin, Michael N. Huhns

Faculty Publications

No abstract provided.


Being And Acting Rational, Michael N. Huhns Jan 2003

Being And Acting Rational, Michael N. Huhns

Faculty Publications

Rationality alone is insufficient to specify agent design. Using economic theory, we can program agents to behave in ways that maximize their utility while responding to environmental changes. However, economic models for agents, although general in principle, are typically limited in practice because the value functions that are tractable essentially reduce an agent to acting selfishly. Building a stable social system from a collection of agents motivated by self-serving interests is difficult. Finally, understanding rationality and knowledge requires interdisciplinary results from artificial intelligence, distributed.


A Numerical Investigation Of Interior Resonances In The Hybrid Fem/Mom Method, Yun Ji, Hao Wang, Todd H. Hubing Jan 2003

A Numerical Investigation Of Interior Resonances In The Hybrid Fem/Mom Method, Yun Ji, Hao Wang, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

The interior resonance problem that can occur when using a hybrid finite-element method/method of moments (FEM/MoM) method to model electromagnetic scattering problems is investigated. Calculations of the bistatic radar cross section of a coated dielectric sphere are presented using different formulations, solution approaches, and solvers. The solutions using the electric-field integral equation have significant errors near an interior resonance frequency. When the combined-field integral equation is employed, satisfactory solutions can be obtained that do not depend on the particular solution approach or solver.


Self-Assembly Of Fept Nanoparticles Into Nanorings, Weilie L. Zhou, Jibao He, Jiye Fang, Tuyet-Anh Huynh, Trevor J. Kennedy, Kevin L. Stokes, Charles J. O'Connor Jan 2003

Self-Assembly Of Fept Nanoparticles Into Nanorings, Weilie L. Zhou, Jibao He, Jiye Fang, Tuyet-Anh Huynh, Trevor J. Kennedy, Kevin L. Stokes, Charles J. O'Connor

Physics Faculty Publications

The application of nanoparticles as quantum dots in nanoelectronics demands their arrangement in ordered arrays. Shape controlled self-assembly is a challenge due to the difficulties of obtaining proper self-assembling parameters, such as solvent concentration, organic ligands, and nanoparticle size. In this article, hard magnetic FePt nanoparticles were synthesized using a combination approach of reduction and thermal decomposition. The nanoparticles are about 4.5 nm and appeared as truncated octahedral enclosed by the

{100} and {111}

crystal facets of fcc structure. The nanoparticles are of hexagonal close packing and orient randomly in the self-assembly nanoarrays.  By diluting the solution for large-area self-assembly, …


Strength Properties Of Granular Materials, Brenda Novoa-Martinez Jan 2003

Strength Properties Of Granular Materials, Brenda Novoa-Martinez

LSU Master's Theses

This thesis presents the results of the experimental work conducted on glass beads in order to investigate the effects of particle size, confining pressure, and surface roughness on the strength properties of the particulate media. Conventional triaxial compression tests were conducted to investigate those effects. Three different sizes of beads were tested: small (diameter = 0.75 – 1.00 mm), medium (diameter = 1.55 – 1.85 mm), and large (diameter = 3.30 – 3.60 mm). The glass beads were subjected to three different confining pressures: 25-, 100-, and 400-kPa. Smooth and etched beads were tested; the etched surface was achieved by …


Analytical Ise Calculation And Optimum Control System Design, Tony Kealy, Aidan O'Dwyer Jan 2003

Analytical Ise Calculation And Optimum Control System Design, Tony Kealy, Aidan O'Dwyer

Conference papers

In control system theory, a performance index is a quantitative measure of the performance of a system and is chosen so that emphasis is given to the important system parameters. In this paper, the authors demonstrate two methods to determine analytically the ISE performance index value for a FOPDT process model under PI control. The ability of proportional/integral (PI) and proportional/integral/derivative (PID) controllers to compensate most practical industrial processes has led to their wide acceptance in industrial applications. The most direct way to set up PI/PID controller parameters is the use of tuning rules. The second part of this paper …


Heat Transfer In Outdoor Aquaculture Ponds, Jonathan Lamoureux Jan 2003

Heat Transfer In Outdoor Aquaculture Ponds, Jonathan Lamoureux

LSU Master's Theses

An energy balance was developed for heated and unheated earthen aquaculture ponds to 1) determine the relative importance of energy transfer mechanism affecting pond temperature; 2) predict pond temperatures; 3) estimate the energy required to control pond temperatures, and 4) recommend efficient heating and cooling methods. PHATR (Pond Heating and Temperature Regulation), a computer program using 4th order Runge-Kutta numerical method was developed to solve the energy balance using weather, flow rate and pond temperature data. By comparing measured and modeled pond temperatures, the average difference (the average bias) was 0.5°C for unheated ponds and 2.4°C for heated ponds. The …


Staying Afloat: A Risk Analysis Study Of Flooding In South Louisiana, Marlene Tomaszkiewicz Jan 2003

Staying Afloat: A Risk Analysis Study Of Flooding In South Louisiana, Marlene Tomaszkiewicz

LSU Master's Theses

For decades, South Louisiana has been battling with flood risk. The area has been inundated with flood waters several times, whether it is due to tropical weather, strong rainfall events, or rising waters. This has resulted in millions of dollars in damages, and in some instances, the same home has been affected multiple times. Many agree that South Louisiana is just not a livable area to begin with; the risk is just too great. However, abandoning the area is simply not an option. As a result, the flood risk battle ensues. How much risk are we talking about? The Federal …


Axis-Switching In Square Coaxial Jets, Victor Piffaut Jan 2003

Axis-Switching In Square Coaxial Jets, Victor Piffaut

LSU Master's Theses

Airflow from single and coaxial contoured nozzles with a square cross section is studied using constant temperature anemometry. The inner to outer jet velocity ratio is 1.5. The Reynolds number of the outer jet based on the hydraulic diameter of the outer nozzle exit is 15,300. Results are compared to previous data obtained with circular nozzles under the same conditions. Properties of the jets and their shear layers such as turbulence shear layer thicknesses and growth rates were derived from the velocity record. The mixing between the jets and with the external flow was found to be enhanced by passive …


Synthesis, Structure And Properties Of Nanolayered Dlc/Dlc Films, Pankaj Gupta Jan 2003

Synthesis, Structure And Properties Of Nanolayered Dlc/Dlc Films, Pankaj Gupta

LSU Master's Theses

Diamondlike carbon (DLC) films have been explored extensively in the past due to their highly attractive properties. However, the high level of internal stress developed during growth prevents deposition of thick films. Synthesis of DLC/DLC multilayers (DDM) presents a venue to overcome this drawback. In the present study, DLC films and DDM were deposited on Si substrate using dc plasma of CH4 and Ar gas mixture. FTIR was used to analyze the structure of the DLC films. Mechanical properties of the films were characterized by microhardness testing and nanoindentation. The tribological properties were studied by conducting pin-on-disc experiments in …


Numerical Solution Of Ocular Fluid Dynamics, Satish Kumar Jan 2003

Numerical Solution Of Ocular Fluid Dynamics, Satish Kumar

LSU Master's Theses

Numerical calculations of the aqueous humor dynamics in the anterior chamber of both the rabbit and the human eye are presented to delineate the basic flow and transport mechanisms. The calculations are based on a geometrical model of the eye, which represents the Trabecular mesh (TM) as a multi-layered porous zone of specified pore sizes and void fraction. Buoyancy is observed to be the dominant driving mechanism for the convective motion in both orientations (horizontal and vertical) of the eye. Reducing the TM pore size does not appear to have a significant influence on the intra-ocular pressure (IOP) until the …


Modeling Intracranial Fluid Flows And Volumes During Traumatic Brain Injury To Better Understand Pressure Dynamics, Wayne W. Wakeland, James Mcnames, Mateo Aboy, D. Hollemon, Brahm Goldstein Jan 2003

Modeling Intracranial Fluid Flows And Volumes During Traumatic Brain Injury To Better Understand Pressure Dynamics, Wayne W. Wakeland, James Mcnames, Mateo Aboy, D. Hollemon, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

See additional files below for the Presentation.

We describe a computer model of intracranial pressure (ICP) dynamics that evaluates clinical treatment options for elevated ICP during traumatic brain injury (TBI). The model uses fluid volumes as primary state variables and explicitly models fluid flows as well as the resistance, compliance, and pressure associated with each intra - and extracranial compartment (arteries and arterioles, capillary bed, veins, venous sinus, ventricles, and brain parenchyma). The model evaluates clinical events and therapies such as intra - and extra-parenchymal hemorrhage, cerebral edema, cerebrospinal fluid drainage, mannitol administration, head elevation, and mild hyperventilation. The model …


Computational Model For Heat Transfer In The Human Eye Using The Finite Element Method, Umit Cicekli Jan 2003

Computational Model For Heat Transfer In The Human Eye Using The Finite Element Method, Umit Cicekli

LSU Master's Theses

In this work a finite element model for the human eye presented. Thermal analysis was done in order to capture the temperature variation in the human eye. The model was created using advance finite element program ABAQUS. In the model each of the eye's component (cornea, sclera, lens, iris, aqueous and vitreous humor) has own material property. Specific boundary conditions were used for the model. The model incorporates the interaction between eyes components. The Comparisons were done with the available experimental results. The results show that there is a temperature variation in the human eye components with the increasing the …


Selected Chemoautotrophic Processes In Wastewater Treatment: Low Temperature Nitrification Inhibition By An Azo Dye And Biofiltration For Odor Control Of Hydrogen Sulfide, Ronald W. Martin Jr. Jan 2003

Selected Chemoautotrophic Processes In Wastewater Treatment: Low Temperature Nitrification Inhibition By An Azo Dye And Biofiltration For Odor Control Of Hydrogen Sulfide, Ronald W. Martin Jr.

Dissertations, Master's Theses and Master's Reports - Open

Biochemical processes by chemoautotrophs such as nitrifiers and sulfide and iron oxidizers are used extensively in wastewater treatment. The research described in this dissertation involved the study of two selected biological processes utilized in wastewater treatment mediated by chemoautotrophic bacteria: nitrification (biological removal of ammonia and nitrogen) and hydrogen sulfide (H2S) removal from odorous air using biofiltration.

A municipal wastewater treatment plant (WWTP) receiving industrial dyeing discharge containing the azo dye, acid black 1 (AB1) failed to meet discharge limits, especially during the winter. Dyeing discharge mixed with domestic sewage was fed to sequencing batch reactors at 22oC and 7oC. …


Breaking The Silicon Ceiling: Women In Engineering Freshmen Seminar, Aura Ganz, Susannah Howe, Vanessa Rivera, Yuechun Chu Jan 2003

Breaking The Silicon Ceiling: Women In Engineering Freshmen Seminar, Aura Ganz, Susannah Howe, Vanessa Rivera, Yuechun Chu

Engineering: Faculty Publications

In this paper we describe a pilot study for freshmen women engineering students we launched at the College of Engineering at UMass Amherst in the fall of 2002. This pilot study, which targeted increased retention of women in engineering, was comprised of the following three main elements: a weekly seminar, use of Pocket PCs and a web-based information and exchange center. The students' feedback to our seminar was very positive. The students noted that the seminar allayed their fears and concerns about pursuing engineering, provided a (classroom and online) forum for networking with their peers and other women engineers. This …


How To Establish Successful Cooperative Student Learning Centers For Stem Courses, Ronald James Bieniek, Douglas R. Carroll, Cesar Mendoza, Oran Allan Pringle, Ekkehard Sinn, Kai-Tak Wan, Donald C. Wunsch Jan 2003

How To Establish Successful Cooperative Student Learning Centers For Stem Courses, Ronald James Bieniek, Douglas R. Carroll, Cesar Mendoza, Oran Allan Pringle, Ekkehard Sinn, Kai-Tak Wan, Donald C. Wunsch

Physics Faculty Research & Creative Works

Students learn more if they are actively involved in the learning process, particularly in a cooperative manner. Several UMR faculty have operated course-based learning centers (LCs) as part of the campus-wide Learning Enhancement Across Disciplines (LEAD) Program of student learning assistance and enhancement. LCs are designed to assist large numbers of students in a cost- and time-efficient manner that promotes student engagement without requiring undue amounts of faculty time. Course instructors spend time in the open learning environment of the LC, in lieu of office hours, guiding students to master course material and skills in their evolution from novice to …


Mobile Communications And Mobile Services, Keng Siau, Z. Shen Jan 2003

Mobile Communications And Mobile Services, Keng Siau, Z. Shen

Research Collection School Of Computing and Information Systems

As wireless technologies evolve, the coming mobile revolution will bring dramatic and fundamental changes to the world. This revolution has already begun and is gaining momentum. The revolution will impact numerous facets of our daily lives and the way business is conducted. It will provide important data in real time to assist decision makers, exert great influence on communications between businesses and their customers, and transform the way we live our lives. This paper examines issues in providing services via wireless technologies, i.e. mobile services. The paper discusses the challenges facing mobile services, such as changes in business strategies, investment …


Application Of Mechanistic Models In Predicting Flow Behavior In Deviated Wells Under Ubd Conditions, Faisal Abdullah Aladwani Jan 2003

Application Of Mechanistic Models In Predicting Flow Behavior In Deviated Wells Under Ubd Conditions, Faisal Abdullah Aladwani

LSU Master's Theses

Underbalanced drilling (UBD) has increased in recent years because of the many advantages associated with it. These include increase in the rate of penetration and reduction of lost circulation and formation damage. Drilling of deviated and horizontal wells also increased since recovery can be improved from a horizontal or a deviated well. The drilling of deviated wells using UBD method will reduce several drilling related problems such as hole cleaning and formation damage. Prediction of flow and pressure profiles while drilling underbalanced in such wells will help in designing and planning of the well. The main aim of this research …


Feasibility Of Radiographic Absorptiometry Of The Mandible As An Osteoporosis Screening Method, Julie A. Skipper Jan 2003

Feasibility Of Radiographic Absorptiometry Of The Mandible As An Osteoporosis Screening Method, Julie A. Skipper

Browse all Theses and Dissertations

The purpose of this work was to develop and evaluate single- and dual-energy radiographic absorptiometry (RA) for the measurement of mandibular bone mineral density (BMD), using standard dental equipment, that would allow for inexpensive and widespread osteoporosis screening. Accurately measured x-ray tube spectra are important for validating the simulations used in the design of the method. A constrained least-squares deconvolution technique for reducing the detector-induced blurring of the energy spectrum was developed. Application of this analytic correction to spectra acquired with a NaI-photomultiplier detector improved the measured data by 20-60%. Implementation of the screening method is accomplished by simultaneously acquiring …


Analysis Of Molten Carbonate Fuel Cell Performance Using A Three-Phase Homogeneous Model, N. Subramanian, B. S. Haran, P. Ganesan, Ralph E. White, Branko N. Popov Jan 2003

Analysis Of Molten Carbonate Fuel Cell Performance Using A Three-Phase Homogeneous Model, N. Subramanian, B. S. Haran, P. Ganesan, Ralph E. White, Branko N. Popov

Faculty Publications

In this study a three-phase homogeneous model was developed to simulate the performance of the molten carbonate fuel cell (MCFC) cathode. The homogeneous model is based on volume averaging of different variables in the three phases over a small volume element. This approach can be used to model porous electrodes as it represents the real system much better than the conventional agglomerate model. Using the homogeneous model the polarization characteristics of the MCFC cathode was studied under different operating conditions.


A University Wide Smart Card System, Philip Cummins Jan 2003

A University Wide Smart Card System, Philip Cummins

Theses : Honours

Presently, many tertiary educational institutions utilise card technologies for staff and student identification and the support of other related services within the institution. A new type of card technology has been developed known as a Smart Card, where an existing plastic card has an embedded integrated circuit and is capable of expanding the range of applications and services capable within an institution. This thesis will detail the advantages that these new Smart Cards have over existing institution cards, detail other institution's attempts to use Smart Cards and finally, this thesis proposes a suitable system for integrating Smart Cards into an …


Frequency-Hopped Multiple-Access Communications With Noncoherent M-Ary Ofdm-Ask, A. Al-Dweik, Fuqin Xiong Jan 2003

Frequency-Hopped Multiple-Access Communications With Noncoherent M-Ary Ofdm-Ask, A. Al-Dweik, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

A noncoherent, bandwidth-efficient modulation scheme is proposed for frequency-hopping multiple-access (FH-MA) networks. The proposed scheme is a combination of noncoherent M-ary amplitude-shift keying (NMASK) and orthogonal frequency-division multiplexing (OFDM). Using this scheme minimizes the required data bandwidth. The number of frequency slots available to the users increases significantly for a fixed spread-spectrum bandwidth (BWSS). The effect of the multiple-access interference is reduced. Simple and accurate bit error rate expressions have been derived for FH-OFDM-MASK in additive white Gaussian noise channels and for FH-OFDM-ASK in Rayleigh fading channels.


Performance Evaluation Of Sip Based Services In Umts, Maria Isabel Pous Fenollar Jan 2003

Performance Evaluation Of Sip Based Services In Umts, Maria Isabel Pous Fenollar

Theses

With ever increasing penetration of IP technologies and the tremendous growth in wireless data traffic, the wireless industry is evolving the mobile core networks towards IP technology. The 3rd Generation Partnership Project (3GPP) is specifying an IP Multimedia Core Network Sub-System (IMS) in UMTS Release 5 and Release 6, which is adjunct to the UMTS GPRS core network. This IP-based network will allow mobile operators to provide commonly used Internet applications to wireless user. The UMTS IMS uses the Internet Engineering Task Force (IETF) defined text based Session Initiation Protocol (SIP), to control a wide range of anticipated IP-based services …