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2012

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Articles 5041 - 5070 of 6303

Full-Text Articles in Engineering

Micro Grid Stability Improvements By Employing Storage, Sumiti Lamichhane Jan 2012

Micro Grid Stability Improvements By Employing Storage, Sumiti Lamichhane

LSU Master's Theses

Storage devices can be used in a power gird to store the excess energy when the energy production is high and the demand is low and utilize the stored energy when the produced energy cannot meet the high demands of the consumers. This thesis represents a micro grid consisting of a conventional synchronous generator, as well as renewable energy sources, energy storage, and loads in order to investigate the effective energy flow control and transient stability improvement by employing thermal storage. Thermal storage, unlike electrical one (such as battery) is more environmental friendly, has longer life span, and is more …

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An Electronic Architecture For Mediating Digital Information In A Hallway Fac̦Ade, Narendra Nallapeta Aswathanarayana Setty Jan 2012

An Electronic Architecture For Mediating Digital Information In A Hallway Fac̦Ade, Narendra Nallapeta Aswathanarayana Setty

LSU Master's Theses

Ubiquitous computing requires integration of physical space with digital information. This presents the challenges of integrating electronics, physical space, software and the interaction tools which can effectively communicate with the audience. Many research groups have embraced different techniques depending on location, context, space, and availability of necessary skills to make the world around us as an interface to the digital world. Encouraged by early successes and fostered by project undertaken by tangible visualization group. We introduce an architecture of Blades and Tiles for the development and realization of interactive wall surfaces. It provides an inexpensive, open-ended platform for constructing large-scale …

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Fundamental Characterization Of Asphalt Mixtures: Warm Mix Asphalt Technologies In Flexible Pavement Systems, Bhanu Vijay Vallabhu Jan 2012

Fundamental Characterization Of Asphalt Mixtures: Warm Mix Asphalt Technologies In Flexible Pavement Systems, Bhanu Vijay Vallabhu

LSU Master's Theses

Increasing concerns on environment and greenhouse effect, coupled with increased construction prices led to the development of new technologies by the Asphalt industry to produce Asphalt Concrete (AC) pavements. Extensive research is being done to evaluate the impact and performance of these new technologies. Warm Mix Asphalt (WMA) is one of these technologies that allow mixing, production, placing and compaction of asphalt mixes at significantly lower temperatures as compared to the traditional Hot Mix Asphalt (HMA) practice. Lower temperatures result in reduced fuel usage, fume exhausts, greenhouse gas emissions, wear and tear at plants; while enhancing worker health and safety …

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The Impact Of 5s On The Safety Climate Of Manufacturing Workers, Siddarth Srinivasan Jan 2012

The Impact Of 5s On The Safety Climate Of Manufacturing Workers, Siddarth Srinivasan

LSU Master's Theses

The occupational injury rate in the manufacturing sector is higher than the average of all private industries, necessitating safety studies. Occupational safety can be measured through different approaches. Safety climate, a predictive measure of safety, studies the workers’ perceptions of safety of the workplace. This measure includes several dimensions of safety like management commitment, involvement and work place hazard evaluation and was chosen as a method of evaluation in this study. Even though occupational safety is an important concern, management often prioritizes reducing waste and cost. So, there is a necessity for some technique which reduces waste and simultaneously improves …

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Design And Optimization Of 2.5 Dimension Porous Media Micromodel For Nanosensor Flow Experiments, Saade Alexis Bou-Mikael Jan 2012

Design And Optimization Of 2.5 Dimension Porous Media Micromodel For Nanosensor Flow Experiments, Saade Alexis Bou-Mikael

LSU Master's Theses

Micromodels are used to visualize and study pore-scale phenomena such as immiscible displacements in porous media, foam flow behavior, and CO2 flooding. The understanding gained from these experiments can be used to develop models to predict future behavior of the reservoir. Most micromodels are constructed using lithography techniques that are restricted to 2D patterns that require artificial generation or manipulation of images to develop connected micromodels. Characteristics innate to the original rock structure are often lost or skewed in developing micromodels that bear little resemblance to the original media. Alternative microfabrication techniques using a micromilling tool have allowed us to …

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Hurricane Damage Assessment Process For Residential Buildings, Carol C. Massarra Jan 2012

Hurricane Damage Assessment Process For Residential Buildings, Carol C. Massarra

LSU Master's Theses

Assessing an affected area immediately after a severe natural hazard event and saving the resulting data are vitally important in any effort to reduce future economic losses from natural hazards. These data are used as a record of buildings performance and as a major component for statistical analysis and damage modeling studies. Since these data are used as input for these studies, the data must be assessed and collected in a scientific and standardized way. Despite this requirement, neither a systematic damage assessment process nor a standardized data collection protocol is currently available in the United States to ensure that …

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Base-Caged Adenosine Triphosphate As A Model System For Photoactivatable Small Interfering Rna, Amanda Yoesting Hendrix Jan 2012

Base-Caged Adenosine Triphosphate As A Model System For Photoactivatable Small Interfering Rna, Amanda Yoesting Hendrix

LSU Master's Theses

Photocaged adenosine triphosphate (ATP) is one of the earliest examples of exerting spatial-temporal control over the activity of a substrate. The activity of ATP is blocked until near-ultraviolet light exposure photocleaves the cage moiety. Caged ATP has been used for a myriad of applications including kinetic studies of ATP-dependent enzymes. Traditional caging of ATP occurs at the gamma-phosphate, which has been found to competitively inhibit several enzymatic systems. It was hypothesized that blocking access to the adenosine N6 position via cage molecule would prevent the initial enzyme-substrate binding event from occurring prior to photolysis, effectively minimizing competitive inhibition. Utilizing a …

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Non-Rigid Registration Of 2-D/3-D Dynamic Data With Feature Alignment, Huanhuan Xu Jan 2012

Non-Rigid Registration Of 2-D/3-D Dynamic Data With Feature Alignment, Huanhuan Xu

LSU Master's Theses

In this work, we are computing the matching between 2D manifolds and 3D manifolds with temporal constraints, that is we are computing the matching among a time sequence of 2D/3D manifolds. It is solved by mapping all the manifolds to a common domain, then build their matching by composing the forward mapping and the inverse mapping. At first, we solve the matching problem between 2D manifolds with temporal constraints by using mesh-based registration method. We propose a surface parameterization method to compute the mapping between the 2D manifold and the common 2D planar domain. We can compute the matching among …

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Characterization Of Nanogumbos For Future Electronic Devices, Naveen Narayan Jagadish Jan 2012

Characterization Of Nanogumbos For Future Electronic Devices, Naveen Narayan Jagadish

LSU Master's Theses

In our work on hybrid (organic-inorganic) electronic materials (HEMs), we have developed a reasonably facile method for characterizing GUMBOS or a Group of Uniform Materials Based on Organic Salts. In addition to the versatility of traditional ionic liquids (i.e.-solubility, melting point, viscosity), NanoGUMBOS are functionalizable to exhibit properties such as fluorescence, magnetic susceptibility, and even antimicrobial activity. However, given our interest in the electrical properties of HEMs, we have made first-time measurements of NanoGUMBOS, using conductive probe Atomic Force Microscopy (CP-AFM), in order to deduce their room temperature current-voltage characteristics. In conjunction with the nanoscale imaging of AFM alone, we …

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Rapid Microwave Drying Of Non-Food Agricultural Feedstock For Improved Biofuel Production, Laura A. Picou Jan 2012

Rapid Microwave Drying Of Non-Food Agricultural Feedstock For Improved Biofuel Production, Laura A. Picou

LSU Master's Theses

Due to limited supply of traditional fossil based fuels, and increased interest in air and water quality along with other environmental concerns, there has been a rise in the utilization of biomass based energy sources. Many agricultural materials can be used for the production of biofuels, including materials that are typically underutilized such as sweet sorghum bagasse and otherwise nuisance species such as Chinese tallow tree seeds. The goal of this project was to examine the relationship between the dielectric properties of sweet sorghum bagasse and Chinese tallow tree (CTT) seeds, respectively, and frequency and moisture content; to determine pertinent …

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Impact Of Lean Production On Workers' Exposure To Risk In Modular Home Building Manufacturing, Joel James Jan 2012

Impact Of Lean Production On Workers' Exposure To Risk In Modular Home Building Manufacturing, Joel James

LSU Master's Theses

The construction industry records the highest number of work-related injuries and fatalities in the United States according to the Bureau of Labor Statistics. Workers’ exposure to risk may be affected by implementing Lean concepts. This study describes the effects on worker’s safety environment after a Kaizen event, a Lean tool, conducted in three workstations within a modular home manufacturer: base-framing, sheet-rock hanging, and painting. The effects of Lean on safety hazards at each of the three workstations were determined by conducting a Job Safety Analysis (JSA) before and after each Kaizen. Based on the JSAs a risk assessment tool (questionnaire) …

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Down-Modulation Of Mica On Malignant Glioma Cells By Herpes Simplex Virus, Carl Irwin Odom Jan 2012

Down-Modulation Of Mica On Malignant Glioma Cells By Herpes Simplex Virus, Carl Irwin Odom

All ETDs from UAB

Glioblastoma Multiforme is a primary malignancy of the central nervous system and is fatal for patients despite surgical resection and radiotherapy. Oncolytic Herpes Simplex Virus (oHSV) vectors deleted of the γ134.5 neurovirulence gene are potential therapies for treating glioblastoma tumors. Although replication in permissive cells is considered the primary mechanism of oHSV mediated tumor clearance, there is evidence that the immune system is part of the tumor clearance mechanism during treatment with oncolytic viruses. Specifically, natural killer (NK) cells may be important for tumor clearance during oHSV therapy. NK cell activation relies partially on the stimulation of activating or inhibitory …

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Investigating Potential Novel Angiogenic And Immunogenic Properties Of Heme Oxygenase-1, Carl Antonio Frizell Jan 2012

Investigating Potential Novel Angiogenic And Immunogenic Properties Of Heme Oxygenase-1, Carl Antonio Frizell

All ETDs from UAB

INVESTIGATING POTENTIAL NOVEL ANGIOGENIC AND IMMUNOGENIC PROPERTIES OF HEME OXYGENASE-1 According to the American Heart Association and Centers of Disease Control and Prevention, cardiovascular diseases comprise the primary causes of death in the United States. Heme oxygenase-1 (HO-1), an inducible microsomal enzyme, catalyzes the rate limiting step in heme degradation releasing equimolar amounts of biliverdin, iron and carbon monoxide. Importantly, the induction of HO-1 is an adaptive response that affords protection in these disease states and several others. Expression of HO-1 has been demonstrated in several disease states and pathophysiological processes, including ischemia-reperfusion, inflammation and organ transplantation. This protection is …

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Low-Order Modeling Of Micro-Flier Impact With Thin Stationary Energetic Targets, Mark B. Fry Jan 2012

Low-Order Modeling Of Micro-Flier Impact With Thin Stationary Energetic Targets, Mark B. Fry

LSU Master's Theses

The impact of high-speed (500-1500 m/s), laser driven micro-fliers with thin energetic targets (10-100 &# 956;m) is being examined to characterize impact-induced heating and combustion of these materials. Aluminum fliers are propelled by a laser into a thin metallic target plate having a layer of energetic material deposited on its backside. Mass spectrometry is performed in vacuo on the energetic side to interrogate the shock-induced chemistry of the energetic material. It is important to ignite and possibly detonate the energetic material without perforation of the target plate avoiding contamination of the vacuum chamber. To guide development of these experiments, a …

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Combinatorial Multi-Level Mold Inserts Using Micro Machining And X-Ray Lithography, Oblesh Jinka Jan 2012

Combinatorial Multi-Level Mold Inserts Using Micro Machining And X-Ray Lithography, Oblesh Jinka

LSU Master's Theses

The present technology advancement in biomedical, micro-electro-mechanical systems (MEMS) engineering, bio-MEMS, healthcare, etc. is driving the need to fabricate devices with multi-level, high aspect ratio and complex microstructures, which in turn requires high quality mold inserts with all these features. The present thesis is concentrated in fabricating a multi-level mold insert with complex quasi 3 dimensional micro structures with dimensions down to 10µm and aspect ratios greater than 30 using a process combination of micro milling with X-ray lithography. Therefore, in this study the main focus was to fabricate a high quality mold insert template, which can be electroplated to …

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Biodiesel Production From Microalgae: Co-Location With Sugar Mills, Christian Lohrey Jan 2012

Biodiesel Production From Microalgae: Co-Location With Sugar Mills, Christian Lohrey

LSU Master's Theses

Co-location of algae production facilities with sugarcane mills in Louisiana was investigated as a way to address the bottlenecks for algal biodiesel production. Using the process modeling software Sugars™, an algal biodiesel production process was integrated with the operation of a typical-sized 10,000 metric tons/day (11,000 short tons/day) sugarcane mill to evaluate material and energy balances. A process is proposed wherein alga production is supplemented with energy, water, and CO2 available from a sugarcane mill. The Energy Return on Invested, EROI (a ratio of the energy produced/energy required) of the proposed algal biodiesel production process was 1.25; meaning 25% more …

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Modulation Of Mesenchymal Stem Cell Behavior By Nano And Micro-Sized Beta-Tricalcium Phosphate Particles In Suspension And Composite Structures, Lekeith Terrell Jan 2012

Modulation Of Mesenchymal Stem Cell Behavior By Nano And Micro-Sized Beta-Tricalcium Phosphate Particles In Suspension And Composite Structures, Lekeith Terrell

LSU Master's Theses

Nano and micro particles have steadily grown in interest for synthetic bone composite structures. Nano and micro sized calcium phosphates especially are of interest because of the osteoinductive behavior of calcium phosphate. Engineered composites incorporating polymers and ceramics, such as poly l-lactic acid (PLLA)/β-TCP, for bone tissue regeneration have been well investigated for their proliferative and osteoinductive abilities. Limited research has been done to thoroughly investigate the effects of various sized β-TCP particles on human mesenchymal stem cell behavior. Foreign bodies are known to elicit an inflammatory and cytotoxic response and several nano-particles are known to elicit cytotoxic and pro-inflammatory …

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Evaluation Of Phosphorous And Nitrogen Removal In Alligator And Dairy Wastewater Via Lime And Bentonite Precipitation, Srikanth Bukkapatnam Tirumala Jan 2012

Evaluation Of Phosphorous And Nitrogen Removal In Alligator And Dairy Wastewater Via Lime And Bentonite Precipitation, Srikanth Bukkapatnam Tirumala

LSU Master's Theses

In many situations, the manure produced by confined animal feeding operations (CAFO) needs to be treated before being land applied in order to prevent negative impacts on the environment. Treatment methods are focused on reducing organics, recovering nitrogen and phosphorous. The purpose of this study is to evaluate the efficacy of burnt-lime (Ca(OH)2) and bentonite clay precipitation system of recovering phosphorous from dairy wastewater and alligator wastewater and trapping any possible emissions of ammonia (NH3). Wastewater samples of flush dairy manure from a collection pit, dairy wastewater from an anaerobic lagoon and alligator wastewater from an anaerobic lagoon were investigated …

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The Effect Of Elevated Water Content On Ethanol Combustion, Baine Bernard Breaux Jan 2012

The Effect Of Elevated Water Content On Ethanol Combustion, Baine Bernard Breaux

LSU Master's Theses

Ethanol is currently being considered as a potential alternative to traditional fuels. However, the fuel offers a low return in terms of energy output per dollar invested when compared to fossil fuels. More than 1/3 of the cost associated with bio-ethanol production is devoted to distillation and water removal. This study seeks to validate the use of hydrous ethanol as a practical fuel to be used in lieu of fossil fuels or anhydrous ethanol. Success would reduce the production cost associated with ethanol fuel. Hydrous ethanol was burned in a swirl-stabilized combustor, air is introduced at a constant flow rate …

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A Method To Improve Interest Point Detection And Its Gpu Implementation, Prabakar Karuppannan Gunashekhar Jan 2012

A Method To Improve Interest Point Detection And Its Gpu Implementation, Prabakar Karuppannan Gunashekhar

LSU Master's Theses

Interest point detection is an important low-level image processing technique with a wide range of applications. The point detectors have to be robust under affine, scale and photometric changes. There are many scale and affine invariant point detectors but they are not robust to high illumination changes. Many affine invariant interest point detectors and region descriptors, work on the points detected using scale invariant operators. Since the performance of those detectors depends on the performance of the scale invariant detectors, it is important that the scale invariant initial stage detectors should have good robustness. It is therefore important to design …

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Double-Bond Isomerization Of Long Chain Olefins, James Edward Bruno Jan 2012

Double-Bond Isomerization Of Long Chain Olefins, James Edward Bruno

LSU Master's Theses

Bruno, James Edward, B.S., Western Michigan University, 2010 Master of Science, Fall Commencement, 2012 Major: Chemical Engineering Double-Bond Isomerization of Long Chain Olefins Thesis directed by Professor Kerry Dooley Pages in thesis, 54. Words in Abstract, 349. ABSTRACT Alkenyl Succinic Anhydride (ASA) is commonly used in the paper industry as a sizing agent. ASA is produced by reacting maleic anhydride with long-chain internal olefins. Such olefins are only available with the double bond in the terminal position, so an isomerization step is necessary. The isomerization can be catalyzed using solid strong acid catalysts, such as those containing sulfonic acid groups. …

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Boron Composite Nanoparticles For Enhancement Of Bio-Fuel Combustion, Neng Wang Jan 2012

Boron Composite Nanoparticles For Enhancement Of Bio-Fuel Combustion, Neng Wang

LSU Master's Theses

Bio-fuels such as ethanol are good candidates to replace fossil fuels, which are being depleted, and whose combustion is associated with net production of greenhouse gases and other environmental issues. However, bio-fuels have low energy densities and can be subject to incomplete combustion. Boron is a promising additive for bio-fuels in combustion applications. It can increase their overall heat release and reduce ignition temperature, because boron itself is among the highest energy density materials. In this study, different B/rare earth oxide and B/Fe composite nanoparticles were produced by simple mechanical milling. Also, a new low temperature milling method was developed …

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Factors Controlling Macondo Oil Biodegraqdation On A Rapidly Eroding Coastal Headlands Beach, Marilany G. Urbano Jan 2012

Factors Controlling Macondo Oil Biodegraqdation On A Rapidly Eroding Coastal Headlands Beach, Marilany G. Urbano

LSU Master's Theses

Fourchon Beach, located along the southeast Louisiana coast, was affected by the oil leaking from the British Petroleum’s Deepwater Horizon Oil rig explosion in 2010. The oil, labeled MC252 oil, came ashore in a stable emulsion form, contaminating the sand, salt pan, marsh and mangroves along the beach. A unique oil form, labeled SSRB (small surface residue ball) was formed from the MC252 oil and a combination of environmental factors. The SSRB is an aggregate of sand and emulsified oil, and forms a large portion of the oil still present on the supratidal zone of Fourchon Beach. SSRBs have not …

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A Novel Rna Extraction Method For Cyanobacteria, Zenghui Zhang Jan 2012

A Novel Rna Extraction Method For Cyanobacteria, Zenghui Zhang

LSU Master's Theses

Research on production of polyhydroxyalkanoates (PHA) by microorganisms has captured attention over the last two decades, since PHA have similar properties as petroleum-based thermoplastics, yet are close to carbon neutral and made from renewable sources. Cyanobacteria are considered to be good PHA producers because of their simple nutrient requirements (mainly water, sunlight and CO2) and fast cell growth. However, knowledge of metabolisms behind PHA production by cyanobacteria is limited. Therefore, gene expression analysis of cyanobacteria is required to get a thorough understanding at the molecular level, and gene expression analysis requires the extraction of high quality RNA. Extracting high quality …

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A Review Of Offshore Blowouts And Spills To Determine Desirable Capabilities Of A Subsea Capping Stack, Louise Matilde Smith Jan 2012

A Review Of Offshore Blowouts And Spills To Determine Desirable Capabilities Of A Subsea Capping Stack, Louise Matilde Smith

LSU Master's Theses

The events surrounding the Deepwater Horizon disaster have changed the face of deepwater operations. In order to continue drilling in the Gulf of Mexico, the regulatory body, the Bureau of Safety and Environmental Enforcement (BSEE), has required that applications to conduct work in the Gulf of Mexico (GOM) include a plan to stop, capture, or contain any uncontrolled release of fluids. The capping and containment systems built and implemented by BP during the event are an excellent starting point for minimizing pollution from deepwater subsea blowouts, but the system has limitations. The industry recognizes these limits but is currently focused …

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Consensusability Of Discrete-Time Multi-Agent Systems, Abhishek Pandey Jan 2012

Consensusability Of Discrete-Time Multi-Agent Systems, Abhishek Pandey

LSU Master's Theses

The study of multi-agent systems (MAS) focuses on systems in which many intelligent agents interact within an environment. The agents are considered to be autonomous entities. MAS can be used to solve problems that are difficult or impossible for an individual agent to solve. The main feature which is achieved when developing MAS, if they work, is flexibility, since MAS can be added to, modified and reconstructed, without the need for detailed rewriting of the application. MAS can manifest self-organization as well as self-steering related complex behaviors even when the individual strategies of all their agents are simple. The goal …

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Evaluation Of Methods To Operate Gate Valves Using Elapsed Time, Rating Of Perceived Exertion, And Electromyography, Francis Williams Hutchinson Jan 2012

Evaluation Of Methods To Operate Gate Valves Using Elapsed Time, Rating Of Perceived Exertion, And Electromyography, Francis Williams Hutchinson

LSU Master's Theses

Hutchinson, Francis Williams, B.G.S., Louisiana State University, 1989 Master of Science in Industrial Engineering, Summer Commencement, 2012 Major: Industrial Engineering Evaluation Of Methods To Operate Gate Valves Using Elapsed Time, Rating Of Perceived Exertion, And Electromyography Thesis directed by Professor Fereydoun Aghazadeh, Ph.D., PE Pages in thesis, 86. Words in abstract, 253. ABSTRACT Industrial valve handwheels are in common use in many industries to block, allow, or regulate the flow of materials within a system. Significant numbers of musculoskeletal disorders have been attributed to turning valve handwheels. The torques encountered to “break” and/or turn these handwheels often exceeds 100 Nm …

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Effect Of Electrical Vehicles On Residential Distribution Systems, Paul Haley Jan 2012

Effect Of Electrical Vehicles On Residential Distribution Systems, Paul Haley

LSU Master's Theses

This thesis focuses on the present state of electrical vehicles (EVs) in the market and the effects that these vehicles could have on residential distribution systems. The current EVs available on the market and the current level of market penetration were investigated. Advantages and disadvantages of EVs from a consumer and governmental perspective were identified. The efficiencies of the whole energy delivery process of electrical vehicles and gasoline vehicles were estimated. Efficiency estimation was used to estimate the impact of EVs on the consumption of fossil fuels and emission of greenhouse gases. Measurement of an EV battery charging cycle and …

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Shear Strength Evaluation Of An Erosional Soil System At Fourchon Beach, Jacques Pierre Boudreaux Jan 2012

Shear Strength Evaluation Of An Erosional Soil System At Fourchon Beach, Jacques Pierre Boudreaux

LSU Master's Theses

South Louisiana is vanishing. Subsidence due to relative sea level rise with erosion of weak wetland soils together produce devastating rates of land loss for this area. It is believed that high rates of erosion are due to weak strength properties of fine-grained sediments in the beaches, marshes, and other wetlands in coastal Louisiana. Wave action is known to initiate the movement of weak coastal soils in a manner that is related to the difference between the shear stresses applied by waves and the critical shear strength of erosional sediments. Direct shear tests were performed on samples obtained from the …

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Catalytic Oxidative Desulfurization: A Comparison Of Reactors, Andrew Marshall Madrid Jan 2012

Catalytic Oxidative Desulfurization: A Comparison Of Reactors, Andrew Marshall Madrid

LSU Master's Theses

A novel technology, a pulsed oscillating monolith reactor (POMR), was compared to a standard autoclave reactor for oxidative desulfurization (ODS) of a model diesel fuel. Two classes of catalysts, mesoporous Ti-MCM-41 and Pd on carbon, were used for ODS. The oxidants used were O2 and peroxide. The model diesel compound was 75 wt% alkanes, 24 wt% alkylaromatic, 0.95 wt% sulfur heterocycles and 0.05% nitrogen heterocycles. ODS reactions were conducted from 343-423 K and pressures from 1.0-1.3 MPa O2. The only component that was not oxidized was the alkane. The POMR showed promise; there was up to a factor of 20 …

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