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LSU Master's Theses

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Full-Text Articles in Engineering

A Study On Buckled-Beam Actuators For Rf Mems Applications, Seunghoon Park Jan 2007

A Study On Buckled-Beam Actuators For Rf Mems Applications, Seunghoon Park

LSU Master's Theses

When combined with MEMS actuators, a mechanical lock is a useful device for various applications including memory cells, micro-relays, micro-valves, optical switches, and digital micro-mirrors. It allows removal of actuation force during idle periods without affecting an actuated state of a device, which makes standing power consumption completely unnecessary. In this thesis, a bistable buckled-beam actuator for RF MEMS switch applications has been examined. The buckled-beam geometry was designed based upon theoretical analysis. It was fabricated by SU-8 lithography and copper pulse electroplating. It was actuated by the Lorentz force using external magnet and current flow through the beam. Measured …


Design, Fabricaton, And Testing Of A Compact Quasi-Isothermal Prox Reactor Using Micro Heat Exchangers, Curtis Maurice Hebert Jan 2007

Design, Fabricaton, And Testing Of A Compact Quasi-Isothermal Prox Reactor Using Micro Heat Exchangers, Curtis Maurice Hebert

LSU Master's Theses

A two stage PROX reactor with micro heat exchangers was designed, built, and tested to demonstrate the ability to control the temperature in the reactor and improve PROX performance in terms of CO conversion and selectivity. The gas stream was composed of 40% H2, 1% CO, 9% CO2, 0.5% O2, and 49.5% Ar. Metal foams were used to support a 5 wt% Pt/0.5 wt% Fe/γ-Al2O3 catalyst. Two sections of foam catalyst were used with heat exchangers positioned before and after each section. The resulting axial temperature profile of the gas stream …


Evaluation Of Shear Strength Parameters Of Shale And Siltstone Using Single Point Cutter Tests, Mahendra Shewalla Jan 2007

Evaluation Of Shear Strength Parameters Of Shale And Siltstone Using Single Point Cutter Tests, Mahendra Shewalla

LSU Master's Theses

Detournay and Tan (2002) performed experiments with a rock cutting device to measure the load required to fail the rock under confining stress. They proposed models describing the correlation between the specific energy and confining stress for shear dilatant rocks as a function of unconfined specific energy at failure, cutter rake angle (θ), internal friction angle (φ) of the rock and an assumed interface friction angle (ψ) between the rock and the cutter. The aim of this research is to evaluate the model proposed by Detournay and Tan (2002), which states that specific energy varies linearly with bore hole pressure …


Experimental Investigation Of Heat Transfer Rate In Micro-Channels, Pritish Ranjan Parida Jan 2007

Experimental Investigation Of Heat Transfer Rate In Micro-Channels, Pritish Ranjan Parida

LSU Master's Theses

Metal-based MHEs are of current interest due to the combination of high heat transfer performance and improved mechanical integrity. Efficient methods for fabrication and assembly of functional metal-based MHEs are essential to ensure the economic viability of such devices. The present study focuses on the results of heat transfer testing of assembled Cu- and Al- based microchannel heat exchanger (MHE) prototypes. Efficient fabrication of Cu- and Al- based high-aspect-ratio microscale structures (HARMS) have been achieved through molding replication using surface engineered, metallic mold inserts. Replicated metallic HARMS were assembled through eutectic bonding to form entirely Cu- and Al- based MHE …


Study Of Ranking Irregularities When Evaluating Alternatives By Using Some Electre Methods And A Proposed New Mcdm Method Based On Regret And Rejoicing, Xiaoting Wang Jan 2007

Study Of Ranking Irregularities When Evaluating Alternatives By Using Some Electre Methods And A Proposed New Mcdm Method Based On Regret And Rejoicing, Xiaoting Wang

LSU Master's Theses

Multi-criteria decision-making (MCDM) is one of the most widely used decision methodologies in the sciences, business, and engineering worlds. MCDM methods aim at improving the quality of decisions by making the process more explicit, rational, and efficient. One intriguing problem is that oftentimes different methods may yield different answers to the same decision problem. Thus, the issue of evaluating the relative performance of different MCDM methods is raised. One evaluating procedure is to examine the stability of an MCDM method’s mathematical process by checking the validity of its proposed rankings. The ELECTRE II and III methods are two well-known MCDM …


A Collaborative High Performance And Grid Computing Portal, Prathyusha Akunuri-Venkata Jan 2007

A Collaborative High Performance And Grid Computing Portal, Prathyusha Akunuri-Venkata

LSU Master's Theses

The world of high performance and grid computing is so vast that it always poses constant challenges and high learning curves to researchers and scientists. A Portal-based solution facilitates a simple web-based graphical user interface that helps the non computer science users take advantage of highly evolving, on-demand, distributed computing to carry out their research activities. A collaborative portal brings together various resources, applications and services under one roof and provides a single point of entry and access to the users. This thesis work endeavors to build a unique High Performance and Grid Computing Portal that combines two existing high …


Juvenile Crawfish (Procambarus Clarkii) Lc50 Mortality From South Louisiana Crude, Peanut And Mineral Oil, Okey Umejuru Jan 2007

Juvenile Crawfish (Procambarus Clarkii) Lc50 Mortality From South Louisiana Crude, Peanut And Mineral Oil, Okey Umejuru

LSU Master's Theses

Nearly every continent has species of crawfish that inhabit wetlands or are near coastal areas where petroleum and other oils are produced, transported, and accidentally released. Most crawfish cannot tolerate polluted water. Thus, they could serve as biomonitors of fossil fuel, biofuel, and other oil releases and assess potential negative impacts such oils have on wetland and coastal ecosystems. The objectives of this study were to estimate the acute toxicity of three oils to juvenile crawfish and determine if toxicity was due to poisoning or interference with oxygen transfer across the gills. Juvenile crawfish (Procambarus clarkii) were tested for acute …


Film Cooling From A Row Of Holes Supplemented With Anti Vortex Holes, Alok Dhungel Jan 2007

Film Cooling From A Row Of Holes Supplemented With Anti Vortex Holes, Alok Dhungel

LSU Master's Theses

Film cooling is a technique employed to protect the external surface of gas turbine blades from the hot mainstream gas by ejecting the internal coolant air through discrete holes or slots at several locations on the blade exterior surface. Passing the coolant through conventional cylindrical holes causes a pair of vortices to form which lifts off the coolant jet instead of letting it adhere to the surface. The present study aims at investigating the enhanced cooling performance caused by addition of anti-vortex holes to the main cylindrical film cooling holes. Both heat transfer coefficient and film cooling effectiveness are determined …


Photo-Control Of Antisense Activity In Cell Culture Using Caged Oligodeoxynucleotides, Mindi Huguet Faubion Jan 2007

Photo-Control Of Antisense Activity In Cell Culture Using Caged Oligodeoxynucleotides, Mindi Huguet Faubion

LSU Master's Theses

Antisense oligodeoxynucleotides (AS ODNs) are short single-stranded pieces of DNA that are designed to hybridize with messenger RNA and thus offer a powerful technique for controlling gene expression. Phosphorothioate AS ODNs are a well-established modification of the traditional phosphodiester structure that increase the in vitro half-life of AS ODN activity. In this work, we describe a method for controlling the hybridization activity of PS ODNs in cell culture with a photo-reversible mechanism. The influence of a photocaging compound, 1-(4,5-dimethoxy-2-nitrophenyl)diazoethane (DMNPE) on hybridization of ISIS 2302, a 20-mer PS ODN, was modeled using a molecular beacon assay. Based on this model, …


Differential Space Time Modulation And Demodulation For Time Varying Multiple Input Multiple Output Channels, Chetan Neginhal Chitnis Jan 2007

Differential Space Time Modulation And Demodulation For Time Varying Multiple Input Multiple Output Channels, Chetan Neginhal Chitnis

LSU Master's Theses

Over the last decade there has been considerable interest in wireless communication using multiple transmit and receive antennas. Several literatures exists that show that these multiple link support very high data rates with low error probabilities when the channel state information is available at the receiver. However when multiple antennas are employed or when the mobile environments change rapidly, it is not always possible to have apriori knowledge of the channel state matrices which calls for Differential Space-Time modulation techniques. Differential modulation is used in conjunction with Unitary Space-Time codes to evaluate their performance over time varying channels. Jakes model …


Fabrication Of Perforated Polymer Membranes Using Imprinting Technology, Anish Roychowdhury Jan 2007

Fabrication Of Perforated Polymer Membranes Using Imprinting Technology, Anish Roychowdhury

LSU Master's Theses

The goal of the present study was to fabricate perforated membrane structures in polymers with the pore diameter ranging from 10 ìm down to the sub ìm scale. The perforated membrane structure plays an important role in many biological systems. Thus the ability to reproduce such architecture will help with the study of biological systems by mimicking biological cell membrane-like structures and open new vistas in the study of transport behavior in cell biology and the separation of biological vesicles. Such structures also have potential uses as components in polymer optics and modular micro/nanofluidic devices. Use of polymer substrates is …


Comparative Study On Double-Rotor Pm Brushless Motors With Cylindrical And Disc Type Slot-Less Stator, Pavani Gottipati Jan 2007

Comparative Study On Double-Rotor Pm Brushless Motors With Cylindrical And Disc Type Slot-Less Stator, Pavani Gottipati

LSU Master's Theses

Among brushless permanent magnet machines, the torus motors (also called Axial Flux Double-Rotor Permanent Magnet (AFTR PM) motors) are most compact and highly efficient. A cylindrical counterpart of this motor is a newly proposed Radial Flux Double-Rotor Permanent Magnet (RFTR PM) motor. The objectives of this thesis are to optimize the magnetic circuit of both AFTR PM and RFTR PM motors and to compare their electromechanical parameters on the basis of the results obtained from magnetic field simulation using Finite Element Method (FEM). To reach these objectives, FEM models are developed for both the motors, for particular given data. Applying …


Manufacturing And Characterization Of High-Aspect-Ratio Diffusive Micro-Mixers, Vamsidhar Palaparthy Jan 2007

Manufacturing And Characterization Of High-Aspect-Ratio Diffusive Micro-Mixers, Vamsidhar Palaparthy

LSU Master's Theses

In the Ligase Detection Reaction (LDR) technique different chemical reagents of varying concentration are mixed with the by-products of the polymerase chain reaction (PCR) for the detection of low abundant cancer diagnostic markers [1]. An effective micro-mixer which is cheap, durable over a relatively broad range of flows with easy manufacturing is required in this process. This work is aimed at manufacturing mixers according to the required specifications with metrology at every manufacturing process to estimate the limits and tolerances during manufacturing and analyzing their efficiency both numerically and experimentally. An optimum mixer design developed earlier by Maha et.al [2] …


Level Basin Approaches To Improve Water Management In Surface Irrigation For Northeast Louisiana, Luis R. Ocampo Briceno Jan 2007

Level Basin Approaches To Improve Water Management In Surface Irrigation For Northeast Louisiana, Luis R. Ocampo Briceno

LSU Master's Theses

In the state of Louisiana surface irrigation is widely used due to the low start-up cost, typically high rainfall, and soil conditions. Irrigation scheduling is an important practice to achieve water use efficiency in agriculture. The objectives of this study were to compare three different methods to determine crop evapotranspiration (ETc) for soybeans in addition to, evaluate a computer based irrigation scheduling program using real scale fields. Weather variables, soil moisture and irrigation water use collected during the summer months of 2005 and 2006 at a production agriculture farm in northeast Louisiana were studied. The ETc estimates obtained using atmometers …


An Optimal Operational Policy For An Integrated Production-Delivery System Under Continuous Price Decrease, Deniz Mungan Jan 2007

An Optimal Operational Policy For An Integrated Production-Delivery System Under Continuous Price Decrease, Deniz Mungan

LSU Master's Theses

In today’s competitive world, the unit cost of a high-tech product declines significantly over its life cycle. An integrated inventory model for products experiencing continuous decrease in unit cost is studied in this research. In this integrated model a manufacturing facility purchases raw material from outside supplier at a fixed size and supplies a fixed quantity of finished products to a buyer periodically after using its production processes. Moreover, buyers demand frequent deliveries of small lots of finished products since the price is continuously decreasing, and this emphasizes the significance of just-in-time (JIT) inventory management for successful companies in technology-related …


Simulation Study Evaluating Alternative Initial Responses To Formation Fluid Influx During Managed Pressure Drilling, Asis Kumar Das Jan 2007

Simulation Study Evaluating Alternative Initial Responses To Formation Fluid Influx During Managed Pressure Drilling, Asis Kumar Das

LSU Master's Theses

Managed pressure drilling is an innovative technique to precisely manage wellbore pressure. It is particularly applicable for reducing the risk of a kick or lost returns when drilling with a narrow window between pore pressure and fracture pressure. The constant bottomhole pressure method of managed pressure drilling uses annular frictional pressure and choke pressure in addition to mud hydrostatic pressure to achieve precise wellbore pressure control. This project investigated alternative initial responses to kicks to determine which would be most effective and reliable under different well scenarios when applying the constant bottomhole pressure method of managed pressure drilling. Three different …


Direct White Sugar Production: Optimization And Chemical Regeneration Of Fixed-Bed Activated Carbon Adsorbers, Raul Alejandro Cortes Jan 2007

Direct White Sugar Production: Optimization And Chemical Regeneration Of Fixed-Bed Activated Carbon Adsorbers, Raul Alejandro Cortes

LSU Master's Theses

A system for the direct production of white sugar from clarified sugar cane juice in a raw sugar factory has been developed at the Audubon Sugar Institute. This Direct White Sugar Production (DWiSP) system employs a series of columns packed with adsorbent media. Activated carbon is used in the first column(s) as a filter and bulk decolorizer. Ion exchange resins are then used to remove ash and remaining color. Batch testing was performed in order to determine equilibrium parameters. An analytical model was utilized in conjunction with column loading tests to determine dynamic characteristics of the carbon adsorber for use …


Fabrication Of Single Walled Carbon Nanotube (Sw-Cnt) Cantilevers For Chemical Sensing, Jui-Ching Hsu Jan 2007

Fabrication Of Single Walled Carbon Nanotube (Sw-Cnt) Cantilevers For Chemical Sensing, Jui-Ching Hsu

LSU Master's Theses

With the discovery of carbon nanotubes (CNTs), many applications have been implemented based on their unique electronic, mechanical, chemical and optoelectronic properties. One area of applications is in gas sensors for detecting, oxygen, flammable and toxic gases. In our work, the focus is on the fabrication of carbon nanotube (CNT) cantilever sensors for integration with CMOS readout chip which offer increased sensitivity. The higher surface-to-bulk ratio enhances the property and performance of the gas sensor by nanocantilevers. In this work, we present the detection method based on the change in capacitance of the single walled carbon nanotube (SWCNT) cantilever. Carbon …


A Novel Template Stage With Superior Alignment Capability For Nanoimprint And Step And Flash Lithography, Yunmi Jeon Jan 2007

A Novel Template Stage With Superior Alignment Capability For Nanoimprint And Step And Flash Lithography, Yunmi Jeon

LSU Master's Theses

The high-resolution capabilities of imprinting and step and flash lithography make these techniques strong contenders for the next generation lithography. Unfortunately, alignment remains an area of concern for nanoimprint because it must be completed before the template is moved into contact with the wafer. The large forces on the template during the process, even for step and flash, place additional demands on the stiffness as well as the reproducibility of the template stage. In this thesis, a prototype flexure stage has been developed to meet these demands. A compressive load, slightly below the Euler's limit, is used to produce relatively …


Reactive Multilayer Foils And Their Applications In Joining, Xiaotun Qiu Jan 2007

Reactive Multilayer Foils And Their Applications In Joining, Xiaotun Qiu

LSU Master's Theses

In this study, Ni/Al multilayer foils were fabricated by a cold rolling method. A two-stage reaction process was observed in the reaction-ignition experiment. The phase formation process in the cold rolled foils was studied. The first reaction stage with a slow reaction velocity was the lateral growth of Al3Ni phase at isolated nucleation sites and the subsequent coalescence into a continuous layer. The second reaction stage with a fast reaction velocity was the growth of the Al3Ni layers in the direction normal to the Ni/Al interface until all Al was consumed. Afterwards, Al3Ni reacted with the remaining Ni to form …


The Catalytic Partial Oxidation Of N-Tetradecane On Rh And Sr Substituted Pyrochlores, Daniel Haynes Jan 2007

The Catalytic Partial Oxidation Of N-Tetradecane On Rh And Sr Substituted Pyrochlores, Daniel Haynes

LSU Master's Theses

Catalyst deactivation by high levels of sulfur and aromatics limits the catalytic partial oxidation (CPOX) of diesel fuel into a H2-rich stream for fuel cells. These species poison traditional supported metal catalysts because they adsorb strongly to electron dense metal clusters and promote the formation of carbon on the surface. Therefore, it is logical to spatially distribute an active metal into the lattice of a chemically and thermally stable material to create an active catalyst surface that is less likely to accumulate carbon or be deactivated by sulfur. In this work, Rh metal only and Rh + Sr …


Optimum Energy Allocation For Detection In Wireless Sensor Networks, Krishna Kishore Gunturu Jan 2007

Optimum Energy Allocation For Detection In Wireless Sensor Networks, Krishna Kishore Gunturu

LSU Master's Theses

The problem of binary hypothesis testing in a wireless sensor network is studied in the presence of noisy channels and for non-identical sensors. We have designed a mathematically tractable fusion rule for which optimal energy allocation for individual sensors can be achieved. In this thesis we considered two methods for transmitting the sensor observations; binary modulation and M-ary modulation. In binary modulation we are able to allocate the energy among the sensors and protect the individual quantized bits where as the M-ary modulation provides optimum energy allocation only among the sensors. The goal is to design a fusion rule and …


Urban Stream Stabilization Using Regional Hydraulic Geometry Curves For Bankfull Floodplain Design, Jonathan Edward Fourrier Jan 2007

Urban Stream Stabilization Using Regional Hydraulic Geometry Curves For Bankfull Floodplain Design, Jonathan Edward Fourrier

LSU Master's Theses

The objective of this thesis was to determine the effectiveness of hydraulic geometry curves for designing bankfull floodplains to stabilize urban streams. In stable streams bankfull discharge is contained within the stream's banks. Higher flows spread out onto the floodplain where the water's velocity drops due to the increase in area and vegetation. This dissipation of energy promotes sediment deposition, decreases flow velocity, and reduces channel erosion. In cases like Galbraith Drain where historical gage data are not available and bankfull indicators are not present, a degraded stream's bankfull depth may be estimated with hydraulic geometry curves. Over forty cross …


Development Of A Biomass Transducer For Automated Microalgal Bioreactors, Amar Shivaram Hegde Jan 2007

Development Of A Biomass Transducer For Automated Microalgal Bioreactors, Amar Shivaram Hegde

LSU Master's Theses

A highly sensitive miniaturized biomass transducer is necessary for continuous and reliable monitoring of the microalgal biomass in a computer controlled, automated microalgal bioreactor. Previous known methods to determine microalgal biomass applicable in these bioreactors are based on single wavelength turbidimetric or fluorescence. The objectives of this research were to (1) determine the light absorption characteristics of some commercially applicable microalgae in the electromagnetic wavelength range of 200-800 nm (2) design and construct a new miniaturized biomass transducer (3) process the transducer output to correlate with the biomass. Wavelength sensitivity analysis was conducted on the commercially important microalgal species - …


Study Of Demolding Process In Thermal Imprint Lithography Via Numerical Simulation And Experimental Approaches, Zhichao Song Jan 2007

Study Of Demolding Process In Thermal Imprint Lithography Via Numerical Simulation And Experimental Approaches, Zhichao Song

LSU Master's Theses

The objective of present study was to analyze the mechanical behavior of polymer resist during the demolding process, such as stress distribution and evolution; distortion and tilt of microstructures in thermal imprint lithography, a new emerging technique in mass production of micro/nanoscale patterns. One of the most challenging technical issues for thermal imprint lithography is the structural damages during demolding process. Thermal stress, adhesion force and friction force all play important roles in determination of the success of demolding and it is crucial to understand the underlying physics in order to optimize the structure and process design. In present study, …


Magnetically Induced Release Of Fluorescein Isothiocyanate (Fitc) From Polymer Nanoparticle Composites (Pncs), Michelle Urbina Jan 2007

Magnetically Induced Release Of Fluorescein Isothiocyanate (Fitc) From Polymer Nanoparticle Composites (Pncs), Michelle Urbina

LSU Master's Theses

Magnetically induced drug release can be used as a site-specific, minimally invasive pharmaceutical treatment. Its purpose is to increase the efficacy of drug therapies to diseased or damaged tissue and to decrease the amount of unnecessary damage to healthy, surrounding tissue. To prove the concept of drug release by a magnetic field, this study focused on the release of a fluorescent molecule from magnetic polymeric nanoparticle composites (PNCs) via induction of an alternating current (AC) magnetic field. Fluorescent magnetic PNCs used were 250 ?m or less in size, and were made of poly(methyl methacrylate) (PMMA) containing either the magnetic material …


Production Well Operations Optimization In Water Distribution System Using Genetic Algorithm, Vineet Katiyar Jan 2007

Production Well Operations Optimization In Water Distribution System Using Genetic Algorithm, Vineet Katiyar

LSU Master's Theses

The City of Chandler, Arizona lies in semi-arid area and the water resources management has been a major concern by the State citizen. There is always a need of optimizing the available water resources when the rate of demand constantly beats the rate of replenishment. In this study we have developed a management model to link the Chandler water distribution model (EPANET) with the Chandler groundwater flow model (MODFLOW) under an optimization framework (Genetic algorithm). The EPANET model supplied by the Chandler city municipal authority has several improper setting (pumping schedules, valves settings, pressure zones etc.). The original model has …


Pile Capacity Utilization For Bridge Bents Designed Using Simplified Procedures, Md Rubiat Ferdous Jan 2007

Pile Capacity Utilization For Bridge Bents Designed Using Simplified Procedures, Md Rubiat Ferdous

LSU Master's Theses

Bent substructure systems are being used increasingly in bridge construction. Among the various bent systems, pile bents are considered a popular choice due to their effectiveness in reducing time and cost. They are constructed by first driving piles to a specified elevation above the ground surface. Then, a cast-in-place reinforced concrete bent cap ties the piles together at their top end. The current Louisiana Department of Transportation and Development Bridge Design Manual provides guidelines for the structural analysis and construction details for general use in the preparation of plans for pile bents. The manual allows the use of a simplified …


The Electrodeposition Of Cerium/Copper Prox Catalysts On Metal Foam, James Matthew Faubion Jan 2007

The Electrodeposition Of Cerium/Copper Prox Catalysts On Metal Foam, James Matthew Faubion

LSU Master's Theses

A cerium/copper (Ce/Cu) preferred carbon monoxide (CO) oxidation (PROX) catalyst has been synthesized via electrodeposition onto a metal foam monolith. The catalyst was characterized using ICP, TPRS, TPR and SEM/EDS. Preliminary PROX TPRS evidence in a reaction mixture of 1% CO, 0.5% O2, 40% H2 (bal. Ar.) indicated that the highest activity was seen in a sequential deposition, in which Cu was deposited first. The highest CO oxidation activity was obtained when the Ce concentration in the second step was 0.1 M (resulting in a bulk wt% loading of 0.24 Ce:Cu). SEM/EDS analysis indicated that an increase in ceria loading …


A Liquid Lens Based On Electrowetting, Jihwan Park Jan 2007

A Liquid Lens Based On Electrowetting, Jihwan Park

LSU Master's Theses

A primary goal of this work is to develop and characterize a novel liquid lens based on electrowetting. A droplet of silicone oil confined in an aqueous solution works as a lens. Electrowetting then controls the shape of the confined silicone oil, and the focal length may be varied upon an applied electric potential. The planar lens design is employed for easy integration of a lens system into a microfluidic device. The achievements of this work are to develop an electrowetting-based planar liquid lens without an off-the-plane electrode structure and to demonstrate the planar liquid lens with variable focal length …