Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 80

Full-Text Articles in Engineering

Bench-Scale Compost Reactors System And The Self-Heating Capabilities, Michael Alden Vining Jan 2002

Bench-Scale Compost Reactors System And The Self-Heating Capabilities, Michael Alden Vining

LSU Master's Theses

Less expensive bench-scale composting reactor systems which can mimic actual composting process via self-heating are needed. One can achieve such systems without using the expensive temperature feed-back control by properly insulating the bench composting reactors. However, the knowledge of heat generation and transfer in bench composting reactors is essential in properly designing such inexpensive insulation systems. All compost trial temperature profiles illustrated initial elevated temperature levels followed by a slow gradual temperature decreasing phase. Of all of the variables, the airflow rate, the volume and the overall heat transfer coefficient, seem to have the greatest impact on producing thermophilic temperatures. …


Evaluation Of The Hydrocarbon Potential In Low-Salinity Shaly Sand, Fnu Kurniawan Jan 2002

Evaluation Of The Hydrocarbon Potential In Low-Salinity Shaly Sand, Fnu Kurniawan

LSU Master's Theses

This research utilizes reservoir data from an oilfield in Indonesia, which is characterized by shaly sand and low salinity formation water. Both low salinity and shaliness reduce the resistivity contrast between oil and water. The aim of this research was to build a comprehensive interpretation algorithm to evaluate the shaly-sand reservoir in a low salinity formation water using limited well log data. Shaly-sand interpretation is still evolving with numerous researchers conducting investigations of the clay minerals effect on rock conductivity through theoretical and experimental approach. These investigations can be loosely divided into either Fractional Shale Volume models or the Cation …


Numerical Study Of Water Coning Control With Downhole Water Sink (Dws) Completions In Vertical And Horizontal Wells, Solomon Ovueferaye Inikori Jan 2002

Numerical Study Of Water Coning Control With Downhole Water Sink (Dws) Completions In Vertical And Horizontal Wells, Solomon Ovueferaye Inikori

LSU Doctoral Dissertations

Approximately 2.5 billion dollars is spent annually to solve the problem of produced water in oil and gas wells. Downhole Water Sink (DWS) technology is one industry solution to control water coning in oil wells. DWS technology involves the segregated production of oil and water through separate completions with zonal isolation packer. However, several problems have been experienced in the application of the technology in watered-out oil wells. This study identified two factors that could aid in a better modeling of the technology in old vertical wells – inclusion of capillary transition pressures and relative permeability hysteresis. It also identified …


Mechanism Of The Nicofe Ternary Alloy Deposition, Yun Zhuang Jan 2002

Mechanism Of The Nicofe Ternary Alloy Deposition, Yun Zhuang

LSU Doctoral Dissertations

Electrodeposited NiCoFe ternary alloys are of interest for their magnetic and thermophysical properties. The reaction rates and resulting composition and current efficiency are often determined empirically, due to a lack of understanding of the electrodeposition mechanism and coupled mass transport. Therefore, the effects of electrolyte concentration, bulk pH and solution agitation are studied over a wide range of applied current densities to investigate the interrelated behavior of the partial reaction rates. The Fe rate during alloy deposition is independent of Co2+ and Fe2+ bulk concentrations, but is enhanced compared with its single metal rate. Both catalytic and inhibiting effects are …


Optimal Channel Equalization For Filterbank Transceivers In Presence Of White Noise, Ehab Farouk Badran Jan 2002

Optimal Channel Equalization For Filterbank Transceivers In Presence Of White Noise, Ehab Farouk Badran

LSU Doctoral Dissertations

Filterbank transceivers are widely employed in data communication networks to cope with inter-symbol-interference (ISI) through the use of redundancies. This dissertation studies the design of the optimal channel equalizer for both time-invariant and time-varying channels, and wide-sense stationary (WSS) and possible non-stationary white noise processes. Channel equalization is investigated via the filterbank transceivers approach. All perfect reconstruction (PR) or zero-forcing (ZF) receiver filterbanks are parameterized in an affine form, which eliminate completely the ISI. The optimal channel equalizer is designed through minimization of the mean-squared-error (MSE) between the detected signals and the transmitted signals. Our main results show that the …


Hard Surface Coating Experimental Evaluation And Thermomechanical Analysis Of A Seal With Micro Heat Exchanger, Yifan Qiu Jan 2002

Hard Surface Coating Experimental Evaluation And Thermomechanical Analysis Of A Seal With Micro Heat Exchanger, Yifan Qiu

LSU Master's Theses

Mechanical face seals are important components of many rotating machinery. Minimizing the friction between seal faces and efficiently removing the heat generated between seal surfaces are two crucial considerations in the design of mechanical seal. Thin film coating and MEMS technology hold great promise for improving the performance of mechanical seals from the viewpoint of reducing friction and heat at the interface in these two aspects. To reveal what effect the coating and MEMS technology can have on tribological properties of seals, friction and wear characteristics of Ti-C:H coatings on seal-like rings and heat transfer performances of a seal prototype …


Tapered Liga Mold Insert, Ryan Anthony Turner Jan 2002

Tapered Liga Mold Insert, Ryan Anthony Turner

LSU Master's Theses

The applications of microstructures produced by the LIGA process are useful in a broad range of fields including: microfluidics, heat transfer, and mechanics. The Microsystems Engineering Team at Louisiana State University has used the LIGA process as a foundation for the team’s productivity in these areas. Many advances in the processes involved in producing these microstructures have been made in the past increasing the efficiency of the entire process. A modified exposure technique in the lithography stage of the LIGA process is being developed to produce microstructures with a draft angle as opposed to the standard straight walled structures. Electroformed …


Development Of A Phosphorus Management Model To Address Filamentous Algae In A Shallow, Subtropical, Urban Hypereutrophic Lake, Jennifer Eileen Ruley Jan 2002

Development Of A Phosphorus Management Model To Address Filamentous Algae In A Shallow, Subtropical, Urban Hypereutrophic Lake, Jennifer Eileen Ruley

LSU Master's Theses

City Park Lake is a shallow, subtropical, urban hypereutrophic lake located in Baton Rouge, Louisiana. By the late 1970’s, this artificial lake had experienced extreme eutrophication and suffered from frequent algal blooms and fish kills. Restoration of City Park Lake occurred in 1983 and consisted of dredging nutrient-laden sediments and the rehabilitation of sewage pipelines. Pre- and post-restoration water quality monitoring programs have provided valuable information by which to gage the long-term success of the restoration work. Following the restoration effort, dramatic improvements were observed in the lake including lower nitrogen, phosphorus and chlorophyll-a concentrations, reduced frequencies in algal blooms …


Modeling Adsorption Of Cane Sugar Colorant In Packed-Bed Ion Exchangers, Hugh Anthony Broadhurst Jan 2002

Modeling Adsorption Of Cane Sugar Colorant In Packed-Bed Ion Exchangers, Hugh Anthony Broadhurst

LSU Master's Theses

The removal of cane sugar solution colorant by packed-bed ion exchangers was modeled using a linear driving force (LDF) adsorption model. Adsorption of colorant is of interest to the developers of the White Sugar Mill (WSM) process as it is a complex subject. The problem is that color is an indiscrete mixture of many components making it difficult to measure and even more challenging to model. Colorant formation was investigated using gel permeation chromatography (GPC) with the objective of developing a method to define pseudo-components representative of cane sugar solution colorants. WSM is a process for producing white sugar directly …


Utilization Of Rice Bran By Pythium Irregulare For Lipid Production, Hui Zhu Jan 2002

Utilization Of Rice Bran By Pythium Irregulare For Lipid Production, Hui Zhu

LSU Master's Theses

This research investigated the feasibility of utilizing rice bran as feedstock for submerged fermentation of Pythium irregulare to produce fungal lipids, which contain polyunsaturated fatty acids (PUFAs) including arachidonic acid (AA, C20:4n6) and eicosapentaenoic acid (EPA, C20:5n3). The fungal nutrient requirements, temperature characterization and growth modeling were determined in glucose-yeast extract media. Sixteen media combinations based on a 24 factorial design with four levels of glucose and yeast extract ranged from 1% to 4% and 0.25% to 1%, respectively, and corresponding carbon/nitrogen ratio (C/N) ranged from 4 to 64, were examined. The suitable C/N for Pythium irregulare growth ranged from …


The Effects Of Local Hydrodynamics On Mass Transfer In Disordered Porous Media, Gang Guo Jan 2002

The Effects Of Local Hydrodynamics On Mass Transfer In Disordered Porous Media, Gang Guo

LSU Doctoral Dissertations

Interfacial mass transfer in disordered media was studied experimentally and numerically. The dissolution of solid benzoic acid spheres in packed columns showed the existence of spatial variations in mass transfer coefficients in monodisperse and polydisperse packings at the same overall Peclet number. The concept of a local Peclet number (single-particle average) was introduced to quantify the effect of local hydrodynamics on local mass transfer. Correlations between Sherwood number and Peclet number having the form Shi=A·(xiPe)m were used to quantify data from various sites in each packing. These experiments also showed that the exponent m varies …


Quantification Of The Spatial Gradient Of Local Volume Fraction From Tomography Images, Yongping Wang Jan 2002

Quantification Of The Spatial Gradient Of Local Volume Fraction From Tomography Images, Yongping Wang

LSU Master's Theses

Asphalt concrete has three constituents: aggregate, asphalt binder and air voids. In the mixture, aggregates serve as a skeleton of the mixture; asphalt serves as a binder to hold the aggregates together; and air voids prevent asphalt concrete from bleeding to avoid plastic mixes. The properties of asphalt concrete are controlled by the interaction of these three components. In asphalt concrete, asphalt binder, voids and aggregates are not uniformly distributed. The local volume fractions of these constituents vary with spatial locations. As a result, there exist a spatial gradient of the local volume fractions between two locations. Due to the …


Non-Linear Kinematic Hardening Model For Multiaxial Cyclic Plasticity, Marcio Costa Araujo Jan 2002

Non-Linear Kinematic Hardening Model For Multiaxial Cyclic Plasticity, Marcio Costa Araujo

LSU Master's Theses

A model of kinematic work hardening based on Frederick and Armstrong (1966), Phillips and Weng (1975), Chaboche (1979), and Voyiadjis and Basuroychowdhury (1998) is proposed for metal like behavior materials. In this proposed model, ratcheting is taken into account through the observation of the backstress evolution equation, modified by the addition of a new term, . Experimental observations made by Phillips and Lee (1979) showed that the direction of the movement of the center of the yield surface occurs in between the stress rate tensor and the plastic strain rate tensor directions. The new term, added to Chaboche model (1979), …


Bayesian Updating Of Simulated Household Travel Survey Data For Small/Medium Metropolitan Areas, Sirisha Murthy Kothuri Jan 2002

Bayesian Updating Of Simulated Household Travel Survey Data For Small/Medium Metropolitan Areas, Sirisha Murthy Kothuri

LSU Master's Theses

This thesis tests an approach for generating simulated travel survey data that has local characteristics incorporated in it. Travel survey data are generally required for estimating and calibrating travel demand models for a region. The high cost associated with travel surveys puts them beyond the budget of most small/medium MPOs. Therefore simulation of travel survey data provides a viable alternative for these data starved regions to generate data. The simulated data is produced by combining socio-demographic data along with a national survey data set. Updating the simulated data distributions with the distributions obtained by surveying a small sample of local …


Efficient Convolvers Using The Polynomial Residue Number System Technique, Surendar Paruchuri Jan 2002

Efficient Convolvers Using The Polynomial Residue Number System Technique, Surendar Paruchuri

LSU Master's Theses

The problem of computing linear convolution is a very important one because with linear convolution we can mechanize digital filtering. The linear convolution of two N-point sequences can be computed by the cyclic convolution of the following 2N-point sequences. The original sequence padded with N zero’s each. The cyclic convolution of two N-point sequences requires multiplications and additions for its computation. A very efficient way of computing cyclic convolution of two sequences is by using the Polynomial Residue Number System (PRNS) technique. Using this technique the cyclic convolution of two N-point sequences can be computed using only N multiplications instead …


Supercritical Carbon Dioxide Extraction Of Lipids From Raw And Bioconverted Rice Bran, Rohit Badal Jan 2002

Supercritical Carbon Dioxide Extraction Of Lipids From Raw And Bioconverted Rice Bran, Rohit Badal

LSU Master's Theses

Rice bran is often discarded despite its nutritional value because the oil in rice bran easily becomes rancid. This has necessitated the search for a method for utilizing the rice bran. The present study involves the application of supercritical fluid extraction (SFE) and bioprocessing (microbial growth on rice bran media) for increasing the value of the rice bran to produce products of high value (nutraceuticals) with superior health benefit. This study was focused on determining the effect of particle size (>48 mesh and 16-48 mesh) and biotreatment on the yield and quality of rice bran oil. SFE technique (40°C, …


A State-Of-The-Practice Review Of Hurricane Evacuation Plans And Policies, Elba Alicia Urbina Jan 2002

A State-Of-The-Practice Review Of Hurricane Evacuation Plans And Policies, Elba Alicia Urbina

LSU Master's Theses

The events of recent hurricane seasons have made evacuation one of the leading emergency management issues. In 1998 and 1999, Hurricanes Georges and Floyd precipitated the two largest evacuations in U.S. history and perhaps, its two largest traffic jams. In response to the problems experienced during these events, many State Department’s of Transportation (DOT) have begun to take a more active role in the planning, management, and operation of hurricane evacuations. Since the involvement of transportation professionals in the evacuation field has been a fairly recent development; many of the newest practices and policies have only been used once, if …


The Interaction Between Hydrology And Water Quality For Urban Rainfall-Runoff: Implications For Management Strategies, Christopher Michael Dean Jan 2002

The Interaction Between Hydrology And Water Quality For Urban Rainfall-Runoff: Implications For Management Strategies, Christopher Michael Dean

LSU Master's Theses

In urban environments, anthropogenic activity deposits potentially hazardous residuals onto impervious surfaces. To investigate the process of wet-weather constituent transport, twelve rainfall/runoff events collected at an experimental catchment site in Baton Rouge, Louisiana were analyzed for temporal delivery of aggregate constituents (SSC, COD, TDS) as well as dissolved and particulate-bound metal concentrations (Cd, Cu, Pb and Zn). Event mean concentrations for the parameters analyzed often exceeded USEPA discharge limits. Rainfall-runoff events were characterized as either mass-limited or flow-limited. Events designated as mass-limited exhibited a high runoff volume, low vehicle to volume ratio (VPV), high stream power and a low correlation …


Prediction Of Transient Head On Seepage Path Using Boundary Fitted Coordinate (Bfc) System, Sherly Hartono Jan 2002

Prediction Of Transient Head On Seepage Path Using Boundary Fitted Coordinate (Bfc) System, Sherly Hartono

LSU Master's Theses

One of the main causes of levee failure is seepage through levee. This seepage can cause weakening in the levee structure, which in turn can cause sudden levee failure or overtopping of the levee due to levee depression. The purpose of this study is to determine the transient head on the seepage path due to changing water level during flood period. Transient seepage problems are very important as critical condition can occur during this time rather than during steady state condition. Seepage path through a levee can be predicted using the Boundary Fitted Coordinate (BFC) system method. The physical coordinate …


A Correlation Between The Optical And Mechanical Properties Of Novel Polysilane/Polysiloxane Nanocomposites, Sungho Lee Jan 2002

A Correlation Between The Optical And Mechanical Properties Of Novel Polysilane/Polysiloxane Nanocomposites, Sungho Lee

LSU Master's Theses

Polysilanes are ¥ò-conjugated conductive polymers with a one-dimensional Si backbone and organic substituted side chains. The conventional Wurtz-type coupling reaction has been used for preparing various alkyl substituted polysilanes, i.e. poly(di-n-hexyl)silane and poly(hexylmethyl)silane. For each polysilane examples with methoxy (-OCH3) and allyl (-CH2CH=CH2) end caps have been prepared. The solution UV absorption characteristics of the polysilanes at room temperature have been measured, from which the wavelength maximum of the UV-VIS absorption and the absorptivity have been obtained. Allyl end capped polysilanes have the same wavelength maximum as methoxy end capped polysilanes. However, the absorptivities of allyl end capped polysilanes are …


Parametric And Sensitivity Analysis Of A Vibratory Automobile Model, Kanika Nicole Vessel Jan 2002

Parametric And Sensitivity Analysis Of A Vibratory Automobile Model, Kanika Nicole Vessel

LSU Master's Theses

Vibration response is an important aspect of any engineering problem. This thesis deals with developing a method to obtain the vibration, parametric and sensitivity of an automobile analyzed as a 2-DOF rigid body system with damping. The focus of the vibration analysis is to obtain the poles, eigenvectors, and natural frequencies of the system. The parametric analysis gave information on how the natural frequency is affected when one of the parameters is perturbed. Information about how much the system is affected by the change in one parameter is what is obtained from the sensitivity analysis. The theoretical solution contained in …


Wavelength Assignment In All-Optical Networks For Mesh Topologies, Prabhulaiah Bijja Jan 2002

Wavelength Assignment In All-Optical Networks For Mesh Topologies, Prabhulaiah Bijja

LSU Master's Theses

All-Optical Networks employing Dense Wavelength Division Multiplexing (DWDM) are believed to be the next generation networks that can meet the ever-increasing demand for bandwidth of the end users. This thesis presents some new heuristics for wavelength assignment and converter placement in mesh topologies. Our heuristics try to assign the wavelengths in an efficient manner that results in very low blocking probability. We propose novel static and dynamic assignment schemes that outperform the assignments reported in the literature even when converters are used. The proposed on-line scheme called "Round-Robin" assignment outperforms previously proposed strategies such as first-fit and random assignment schemes. …


Experimental Evaluation Of Control Fluid Fallback During Off-Bottom Well Control In Vertical And Deviated Wells, Fernando Sebastian Flores-Avila Jan 2002

Experimental Evaluation Of Control Fluid Fallback During Off-Bottom Well Control In Vertical And Deviated Wells, Fernando Sebastian Flores-Avila

LSU Doctoral Dissertations

This study measured the liquid fallback during simulated blowout conditions. The purpose of the study was to establish a basis for developing a procedure for controlling blowouts that relies on the accumulation of liquid kill fluid injected while the well continues to flow. The results from experiments performed with air, water, 10.5 ppg and 12.0 ppg mud in an experimental 48 ft flow loop at 0°, 20°, 40°, 60° and 75° deviation angles from the vertical, as well as results from full-scale experiments performed with natural gas and water based drilling fluid in a vertical 2787-foot deep research well, are …


Log-Derived Cation Exchange Capacity Of Shaly Sands : Application To Hydrocarbon Detection And Drilling Optimization, Gamze Ipek Jan 2002

Log-Derived Cation Exchange Capacity Of Shaly Sands : Application To Hydrocarbon Detection And Drilling Optimization, Gamze Ipek

LSU Doctoral Dissertations

Researchers at Louisiana State University, LSU, have introduced several petrophysical models expressing the electric properties of shaly sands. These models, to be used for hydrocarbon detection, are based on the Waxman and Smits concept of supplementing the water conductivity with a clay counterions conductivity. The LSU models also utilize the Dual Water theory, which relates each conductivity term to a particular type of water, free and bound, each occupying a specific volume of the total pore space. The main difference between these models and the other shaly sand models is that the counterion conductivity is represented by a hypothetical sodium …


Numerical Reservoir Characterization Using Dimensionless Scale Numbers With Application In Upscaling, Djuro Novakovic Jan 2002

Numerical Reservoir Characterization Using Dimensionless Scale Numbers With Application In Upscaling, Djuro Novakovic

LSU Doctoral Dissertations

Dimensionless space provides a tool for analyzing the behavior of complex systems described by mathematical relationships. The limited application of dimensionless variables in numerical reservoir simulation and experimental design motivated the development of a complete set of dimensionless scaling groups. Inspectional analysis yielded 8 dimensionless groups completely describing the flow system. Further analysis of fluid interaction reduced the number of dimensionless groups to 7. The newly developed dimensionless equations and groups were used for analytical and numerical reservoir characterization, quantifying the behavior of differential and difference equations employed in fluid flow in three-dimensional porous media. The behavior of the dimensionless …


Three-Dimensional Micromachined On-Chip Inductors For High Frequency Applications, Nimit Chomnawang Jan 2002

Three-Dimensional Micromachined On-Chip Inductors For High Frequency Applications, Nimit Chomnawang

LSU Doctoral Dissertations

Demands for wireless communication are ever-escalating for consumer and military communication applications. The requirements of portability, more functionality and lower cost have been driving forces toward smaller, more sophisticated and flexible wireless devices with lower power consumption. To meet these requirements, monolithically integrated passive inductors with high Q-factors and high self-resonant frequencies are desirable. Q-factor and self-resonant frequency of an inductor are significantly degraded at high frequencies due to conductor ohmic loss, magnetically induced eddy current in the conductive substrate, and lower self-resonant frequency from capacitance between conductive substrate and conductors.
In this dissertation, novel three-dimensional arch-like solenoid and dome-shaped …


Liga Mold Insert Fabrication Using Su-8 Photoresist, Jian Zhang Jan 2002

Liga Mold Insert Fabrication Using Su-8 Photoresist, Jian Zhang

LSU Master's Theses

The LIGA process potentially enables economic mass-production of devices with high aspect ratio geometry. Central to the LIGA process is the fabrication of high quality LIGA molds. But in the traditional LIGA mold insert fabrication process, the x-ray photoresist poly-methyl-methacrylate (PMMA) is not highly sensitive to x-rays and a thick piece of PMMA sheet (>1mm) needs too much time to get exposed (bottom dose: 3500J/cm3), which results in excessive cost/ fabrication difficulty of the mold insert. Thus, in this thesis a negative photoresist SU-8 was tested as an x-ray photoresist in the LIGA fabrication process. SU-8 is much more …


Impact Of Subject Related Factors And Position Of Flight Control Stick On Acquisition Of Simulated Flying Skills Using A Flight Simulator, Bo-Keun Cho Jan 2002

Impact Of Subject Related Factors And Position Of Flight Control Stick On Acquisition Of Simulated Flying Skills Using A Flight Simulator, Bo-Keun Cho

LSU Doctoral Dissertations

Increasing demand on aviation industry calls for more pilots. Thus, pilot training systems and pilot-candidate screening systems are essential for civil and military flying training institutes. Before actual flight training, it is not easy to determine whether a flight trainee will be successful in the training. Due to the high cost of actual flight training, it would be better if there were low cost methods for screening and training candidates prior to the actual flight training. This study intended to determine if subject related factors and flight control stick position have an impact on acquisition of simulated flying skills using …


Analysis Of Diagnostic Testing Of Sustained Casing Pressure In Wells, Rong Xu Jan 2002

Analysis Of Diagnostic Testing Of Sustained Casing Pressure In Wells, Rong Xu

LSU Doctoral Dissertations

Over 8,000 wells in the Gulf of Mexico exhibit sustained casing pressure (SCP). SCP is defined as “any measurable casing pressure that rebuilds after being bled down, attributable to cause(s) other than artificially applied pressures or temperature fluctuations in the well”. The Minerals Management Service (MMS) regulations consider SCP hazardous and, in principle, require its elimination. In some cases the agency may allow continuing production at a well with SCP by granting a temporary “departure” permit. The departure permits are based on diagnostic tests involving pressure bleed-down through a 0.5-inch needle valve followed by closing the valve and recording pressure …


Transient Thermomechanical Interactions Of Shaft-Bushing Pair In Bearings - A Finite Element Study, Rajesh Krithivasan Jan 2002

Transient Thermomechanical Interactions Of Shaft-Bushing Pair In Bearings - A Finite Element Study, Rajesh Krithivasan

LSU Master's Theses

This thesis presents a finite element parametric study of the transient thermomechanical interactions of shaft-bushing pairs in bearings to gain insight into the nature of two categories of failures encountered in practice. The first type of failure deals with occurrence of the so-called thermally induced seizure (TIS) during the start-up period followed by an investigation of TIS due to a transient flow-disturbance. The second part deals with the thermomechanical interactions of pin-bushing assembly under heavy oscillating loads where the failure is by TIS and/or thermal galling. An extensive set of parametric simulations covering a wide range of loads, speeds, operating …