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Full-Text Articles in Engineering

“Hydraulic Fracturing Efficiency In The Olmos Sand Formation”, Lauren N. Fogarty Dec 2010

“Hydraulic Fracturing Efficiency In The Olmos Sand Formation”, Lauren N. Fogarty

Honors Theses

No abstract provided.


Catalytic Oxidative Desulfurization Of A Model Diesel, Dongxing Liu Jan 2010

Catalytic Oxidative Desulfurization Of A Model Diesel, Dongxing Liu

LSU Major Papers

An analysis of heterogeneous oxidation catalysts was performed to determine the activities and optimal operating conditions for the multiphase oxidative desulfurization (ODS) reactions, using a model diesel. Catalysts studied included well-characterized Pd on Al2O3 and activated carbon supports, and carbon-supported Mo2C and W2C, which were prepared by temperature programmed reaction. Several other typical oxidation catalysts were also examined. The model diesel consisted of ~1 wt% sulfur compounds (thiophene and dibenzothiophene) with appropriate amounts of aliphatic, alkylaromatic and N-heterocyclic compounds to simulate a raw number 2 diesel. With oxygen as the oxidant in ODS reactions of this model diesel (70-90ºC, 0.8-1.8 …


Degradation Behavior Of Shape Memory Polymer Due To Water And Diesel Fuel, Mohammad Nazmul Hasan Nahid Jan 2010

Degradation Behavior Of Shape Memory Polymer Due To Water And Diesel Fuel, Mohammad Nazmul Hasan Nahid

LSU Master's Theses

Shape memory polymers (SMP) are smart materials, which have the ability to memorize the original or permanent shape. Owing to this characteristic SMP can be used as a sensor, a transplant, as well as structural materials in wide range of applications. Despite its importance, its degradation behavior is still not completely known; and only a limited amount of work has been reported in the literature. In this thesis, the experiments have been carried out to evaluate the degradation behavior of Veriflex- SMP (industry supplied SMP samples) upon exposure to two different types of liquids; water and diesel fuel separately. It …


Development Of A Compact Optical System For A Forward-Looking Endoscope, Anandi Kalyan Dutta Jan 2010

Development Of A Compact Optical System For A Forward-Looking Endoscope, Anandi Kalyan Dutta

LSU Master's Theses

ABSTRACT Optical Coherence Tomography has been effectively used for endoscopy in many previous studies. In this work, a 2 mm diameter forward-looking endoscope is developed with the help of MEMS technology and Optical Coherence Technology (OCT) to obtain in-vivo cross-sectional images of tissues or body cavities. The design consists of a GRIN lens, optical fiber and MEMS chip that are placed in line to fulfill the aim of achieving a 2 mm diameter probe. A standard assembly process has been established for the probe. An anisotropic etching was performed on the sample chip to create the V-groove for carrying the …


Antioxidant Nanoparticles As Delivery Systems, Carlos Ernesto Astete R. Jan 2010

Antioxidant Nanoparticles As Delivery Systems, Carlos Ernesto Astete R.

LSU Doctoral Dissertations

The goal of the study was to develop antioxidant polymeric nanoparticles as a new delivery system for food and pharmaceutical applications. Natural antioxidants like alpha-tocopherol, vitamin C, and carnosine, are responsible to protect biological systems against free radicals attack. The conjugation of vitamin C-vitamin E (EC) and alpha-tocopherol-carnosine (VECAR) were performed to obtain antioxidant surfactants which were used for polymeric nanoparticle synthesis. The surfactant made of á-tocopherol (vitamin E) and ascorbic acid (vitamin C) of antioxidant properties dubbed as EC was used to make poly(lactic-co-glycolic) acid (PLGA) nanoparticles. Self-assembled EC nanostructures and PLGA-EC nanoparticles were made by nanoprecipitation, and the …


Modeling And Multiresolution Characterization Of Micro/Nano Surface For Novel Tailored Nanostructures, Rajib Mukherjee Jan 2010

Modeling And Multiresolution Characterization Of Micro/Nano Surface For Novel Tailored Nanostructures, Rajib Mukherjee

LSU Doctoral Dissertations

Nanofabrication is state of the art technology. Various chemical, mechanical, biochemical and semiconductor products have characteristics controlled by the nanostructures of the surface and interphase. Surface microscopic imaging is generally used to capture different surface features. By properly analyzing the surface image, valuable information regarding manufacturing process and product performance can be extracted. While microscopy measurements can offer very accurate qualitative information about surface features, for many applications, it is critical to obtain a quantitative description of the surface morphology. Various statistical features can be used to characterize the surface in quantitative way. Such an analysis can be done by …


Effects Of Bondline Thickness On Nonlinear Interfacial Fracture Of Bonded Adhesive Joint, Gefu Ji Jan 2010

Effects Of Bondline Thickness On Nonlinear Interfacial Fracture Of Bonded Adhesive Joint, Gefu Ji

LSU Doctoral Dissertations

A number of existing and emerging industrial applications are dependent on layered substrates through adhesive bonding. The interfacial fracture of adhesively bonded structures is a critical issue for its extensive applications to a variety of modern industries. In the recent two decades, cohesive zone models (CZMs) have been receiving intensive attentions for fracture problems of adhesively bonded joints due to its fairly simple and accurate predictive ability. In CZMs the nonlinear interfacial fracture behaviors are described by the traction-separation laws (also referred to as cohesive laws). The cohesive laws represent the local constitutive behavior, instead of the global parameter, such …


An Experimental Study Of Surfactant Enhanced Waterflooding, Paulina Metili Mwangi Jan 2010

An Experimental Study Of Surfactant Enhanced Waterflooding, Paulina Metili Mwangi

LSU Master's Theses

Surfactants have a variety of applications in the petroleum industry due to their remarkable ability to lower the oil-water interfacial tension and alter wettability. However, surfactant adsorption on rock surfaces has severely crippled this means of improving oil recovery due to the high cost associated with the large quantities of surfactant needed. A previous experimental study by Ayirala (2002) reported the development of mixed wettability using a nonionic surfactant. At this mixed-wet state he was able to recover about 94% of the original oil in place. The underlying motivation of this study was to achieve such high recoveries without using …


Fabrication, Characterization, Modeling And Testing Of A Nanostructured Bulk Thermoelectric Cooler, Dinesh Pinisetty Jan 2010

Fabrication, Characterization, Modeling And Testing Of A Nanostructured Bulk Thermoelectric Cooler, Dinesh Pinisetty

LSU Doctoral Dissertations

New generation micro/nano devices are emerging to monitor, control and act on living systems. Particularly, in the field of cryobiology, there is a need to monitor and control temperature at the cellular level. An important step towards achieving this aim is to fabricate a novel bulk nanostructured thermoelectric cooler (TEC). As a first step towards achieving efficient localized control of temperature in biological systems, Bismuth-telluride (Bi2Te3) and Antimony-Telluride (Sb2Te3) arrays of nanowires and nanotubes were fabricated, characterized and modeled. A thermal conductivity model originally developed by Dames and Chen for superlattice nanowires was extended to nanotubes. Based on this model …


Point-Of-Care Immunoassay System Using Carbon Nanotube Labels, Adeyabeba Abera Jan 2010

Point-Of-Care Immunoassay System Using Carbon Nanotube Labels, Adeyabeba Abera

LSU Doctoral Dissertations

The goal of this research was to develop enhanced signal detection mechanisms for immunosensing using carbon nanotubes (CNTs). The utilization of CNT labels for direct electrical measurement was implemented on lateral flow system and microfluidic integrated interdigitated array microelectrodes. These sensing mechanisms in simple and miniaturized system provided higher sensitivity and autonomous flow control for rapid detection aimed at point-of-care diagnostics. Specific functionalization protocols were carried out to chemically modify the surface of the CNTs for uniform dispersion and antibody conjugation in aqueous solution. Surfactant assisted dispersion of the CNTs was studied using PVP and PEG. Covalent conjugation of antibodies …


Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner Jan 2010

Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner

LSU Master's Theses

Safety research and practice have shifted focus away from accident rates and accident causal information to a more proactive approach that may predict organizational safety trends. This proactive approach involves the concept of an organizational safety culture and the use of surveys to measure organizational safety climate or „snapshot‟ of the organizational safety culture. Surveys were administered to line workers, supervisors, and managers at a modular home manufacturing company before and after safety climate information was presented to supervisors and managers in an attempt to measure the effect of the supervisors‟ and managers‟ increased awareness of the factors that define …


Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan Jan 2010

Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan

LSU Doctoral Dissertations

Fuel Cells are attractive power source for use in electronic applications. Physical phenomena (water generation, saturation effect in fuel cell, poisoning, and thermal stress) are studied that governs the operation of a Proton Exchange Membrane Fuel Cell (PEMFC) and Solid Oxide Fuel cell (SOFC). Additionally, experimental studies and numerical simulations on PEMFC gas flow channel, the determination of the impact of the single channel fuel cell are presented. Furthermore, preliminary study is done for the application of APS (Air Plasma Spray) to SOFC and adhesion of anode and cathode with electrolytes for the determination of parameters involved in manufacturing the …


Model-Based Nonlinear Control Of Active Tilting-Pad Bearings, An Wu Jan 2010

Model-Based Nonlinear Control Of Active Tilting-Pad Bearings, An Wu

LSU Doctoral Dissertations

A promising mechanical bearing candidate for active operation is the tilting-pad bearing. The proposed active tilting-pad bearing has linear actuators that radially translate each pad. The use of feedback control in determining the actuator forces allows for the automatic, continuous adjustment of the pad position during the operation of the rotating machine. In the first part of the dissertation, we develop a nonlinear dynamic model of the active bearing system. The hydrodynamic force produced by the fluid film is modeled as a nonlinear, squeeze-film damper plus repellent spring. A model-based nonlinear controller is then designed to exponentially regulate the rotor …


Quantification Of Energy Intake Using Food Image Analysis, Sertan Kaya Jan 2010

Quantification Of Energy Intake Using Food Image Analysis, Sertan Kaya

LSU Master's Theses

Obtaining real-time and accurate estimates of energy intake while people reside in their natural environment is technically and methodologically challenging. The goal of this project is to estimate energy intake accurately in real-time and free-living conditions. In this study, we propose a computer vision based system to estimate energy intake based on food pictures taken and emailed by subjects participating in the experiment. The system introduces a reference card inclusion procedure, which is used for geometric and photometric corrections. Image classification and segmentation methods are also incorporated into the system to have fully-automated decision making.


Operational And Safety Assessment Of Joint And Conventional Lane Merge Configurations For Freeway Work Zones, Pradeep Rayaprolu Jan 2010

Operational And Safety Assessment Of Joint And Conventional Lane Merge Configurations For Freeway Work Zones, Pradeep Rayaprolu

LSU Master's Theses

Inefficient operation of traffic at work zone areas typically leads to increase in travel time delays, queue length, fuel consumption, number of forced merges, and roadway accidents. In order to improve the operational efficiency of work zones, research on freeway work zones constantly seeks to develop different lane merge control strategies, in addition to the conventional lane merge configuration, recommended by the Manual on Uniform Traffic Control Devices. This study evaluates the operational efficiency and safety benefits of a newly proposed configuration, joint lane merge (JLM), and compare its performance with the conventional lane merge (CLM) configuration. A simulation model …


Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso Jan 2010

Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso

LSU Doctoral Dissertations

Efforts are underway in the New Orleans area to raise the elevations of its levee system to combat the effects of hurricane storm surge. When complete, the majority of the system will be comprised of a combination of levees, sheet pile I-Walls, floodgates, and pile-supported concrete floodwalls, commonly referred to as T-Walls. Given the magnitude of the hydrostatic forces associated with storm surge, global instability is failure mechanism that must be considered in the design of T-Walls. In the past, it was assumed that these forces would be resisted by the T-Wall’s sheet pile cut-off wall. Recent literature review and …


Macroinstability And Perturbation In Turbulent Stirred Tank Flows, Somnath Roy Jan 2010

Macroinstability And Perturbation In Turbulent Stirred Tank Flows, Somnath Roy

LSU Doctoral Dissertations

Impeller stirred tank reactors (STRs) are commonly used in the chemical processing industries for a variety of mixing and blending technologies. In this research, a numerical study of flow and mixing inside turbulently agitated STRs are carried out. An immersed boundary method (IBM) is utilized to represent moving impeller geometries in the background of multi-block structured curvilinear fluid. The IBM This curvilinear-IBM methodology is further combined with the large eddy simulation (LES) technique to address the issue of modeling unsteady turbulent flows in the STR. Verification of the combined IBM-LES implementation strategy in curvilinear coordinates is done through comparisons with …


Value-Added Processing Of Rice And Rice By-Products, Rebecca C. Schramm Jan 2010

Value-Added Processing Of Rice And Rice By-Products, Rebecca C. Schramm

LSU Doctoral Dissertations

World competition has encouraged United States rice farmers and rice mills to be efficient in farming and production practices. Efforts to augment economic competitiveness include development of new varieties, improvements in milling practices, and identification of uses for rice products and by-products. The research detailed in this dissertation adds to the body of knowledge in milling practices and identification of uses for rice bran. To improve the prediction of milled rice quality at industrial scale, correlations for milling quality among laboratory, pilot, and industrial scale mills were identified for Clearfield 161. Final industrial product whiteness was ten points higher than …


Identifying And Quantifying Factors Affecting Traffic Crash Severity In Louisiana, Hong Zhang Jan 2010

Identifying And Quantifying Factors Affecting Traffic Crash Severity In Louisiana, Hong Zhang

LSU Doctoral Dissertations

This study was conducted to identify and quantify the factors affecting highway crash severity in Louisiana. Three candidate models were fit to the crash data to compare their performance and the Ordered Mixed Logit (OML) model was selected as the crash severity prediction model of choice. The factors contributing to crash severity identified by the OML model are: age and gender of the driver, vehicle speed, whether alcohol played a role in the crash, whether seatbelts were used, whether the driver was ejected from the vehicle, whether the crash was a head-on collision, whether an airbag was deployed, and whether …


Thermal Conductivity And Its Effects On The Performance Of Pcc Pavements In Mepdg, Upender Kodide Jan 2010

Thermal Conductivity And Its Effects On The Performance Of Pcc Pavements In Mepdg, Upender Kodide

LSU Master's Theses

This study developed a standard thermal conductivity test procedure to test concrete specimens and studied factors influencing those specimens. The thermal conductivity of concrete is significantly affected by moisture content, type, and percentage of coarse aggregate; this finding was confirmed statistically by Analysis of Variance (ANOVA). The study also developed a model for predicting the thermal conductivity of concrete that varies with moisture content and the coarse aggregate percentage. To understand the effect of supplementary cementitious materials (SCMs), this study also measured thermal conductivity of control and ternary mixtures. An increase in thermal conductivity percentage due to increase in moisture …


Optimization Of New Chinese Remainder Theorems Using Special Moduli Sets, Narendran Narayanaswamy Jan 2010

Optimization Of New Chinese Remainder Theorems Using Special Moduli Sets, Narendran Narayanaswamy

LSU Master's Theses

The residue number system (RNS) is an integer number representation system, which is capable of supporting parallel, high-speed arithmetic. This system also offers some useful properties for error detection, error correction and fault tolerance. It has numerous applications in computation-intensive digital signal processing (DSP) operations, like digital filtering, convolution, correlation, Discrete Fourier Transform, Fast Fourier Transform, direct digital frequency synthesis, etc. The residue to binary conversion is based on Chinese Remainder Theorem (CRT) and Mixed Radix Conversion (MRC). However, the CRT requires a slow large modulo operation while the MRC requires finding the mixed radix digits which is a slow …


The Weakening Of Branch Predictor Performance As An Inevitable Side Effect Of Exploiting Control Independence, Christopher Joseph Michael Jan 2010

The Weakening Of Branch Predictor Performance As An Inevitable Side Effect Of Exploiting Control Independence, Christopher Joseph Michael

LSU Doctoral Dissertations

Many algorithms are inherently sequential and hard to explicitly parallelize. Cores designed to aggressively handle these problems exhibit deeper pipelines and wider fetch widths to exploit instruction-level parallelism via out-of-order execution. As these parameters increase, so does the amount of instructions fetched along an incorrect path when a branch is mispredicted. Many of the instructions squashed after a branch are control independent, meaning they will be fetched regardless of whether the candidate branch is taken or not. There has been much research in retaining these control independent instructions on misprediction of the candidate branch. This research shows that there is …


Audio Watermarking Using Transformation Techniques, Rajkiran Ravula Jan 2010

Audio Watermarking Using Transformation Techniques, Rajkiran Ravula

LSU Master's Theses

Watermarking is a technique, which is used in protecting digital information like images, videos and audio as it provides copyrights and ownership. Audio watermarking is more challenging than image watermarking due to the dynamic supremacy of hearing capacity over the visual field. This thesis attempts to solve the quantization based audio watermarking technique based on both the Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT). The underlying system involves the statistical characteristics of the signal. This study considers different wavelet filters and quantization techniques. A comparison is performed on diverge algorithms and audio signals to help examine the performance …


Itraconazole Loaded Poly (Lactic-Co-Glycolic) Acid Nanoparticles For Improved Antifungal Activity, Nipur Rajan Patel Jan 2010

Itraconazole Loaded Poly (Lactic-Co-Glycolic) Acid Nanoparticles For Improved Antifungal Activity, Nipur Rajan Patel

LSU Master's Theses

PLGA (polylactic-co-glycolic acid) nanoparticles containing the hydrophobic antifungal Itraconazole (ITZ) were developed to address the need for more efficient means of treating fungal infections. PLGA-ITZ nanoparticles were synthesized using an oil-in-water emulsion evaporation method. The nanoparticles morphology (TEM), size and size distribution, zeta potential (DLS), encapsulation efficiency (UV-VIS), release profile, and antifungal activity were characterized. The blank NPs and loaded PLGA-ITZ NPs were spherical with diameters of 201±5 nm, 232±1 nm and 223±36 nm at 0%, 12.5% and 25% loadings, respectively. All synthesized particles measured a negative zeta potential ranging from -28 to -33 mV. The maximum encapsulation efficiency of …


Modeling And Analysis Of Radial Flux Toroidally Wound Twin Rotor Permanent Magnet Motor, Ravi Kishore Pratapa Jan 2010

Modeling And Analysis Of Radial Flux Toroidally Wound Twin Rotor Permanent Magnet Motor, Ravi Kishore Pratapa

LSU Master's Theses

The main objective of current thesis is the study of Radial Flux Twin Rotor Permanent Magnet (RFTWTRPM) motor. The tasks were to review the literature about RFTWTPM motors and model the motor using Finite Element Method Magnetics (FEMM 4.0). Later the performance of RFTWTRPM motor as a brushless dc motor was analyzed by using MATLAB/SIMULINK package. To find the electrical and mechanical parameters of the RFTWTRPM motor, the rotor and stator dimensions of the motor were firstly optimized using linear FEMM model of the motor. The optimized dimensions were used to construct the cylindrical FEMM model. This model was later …


Design And Fabrication Of Micronozzles For Drug Delivery Applications, Yuxuan Zhou Jan 2010

Design And Fabrication Of Micronozzles For Drug Delivery Applications, Yuxuan Zhou

LSU Master's Theses

Inhaled drug is an important drug delivery route. It is widely used in medications for respiratory disorders. However, it has some significant limitations, for examples, concentration of drug, output, and particles size, are not accurately controlled in most of the available drug delivery systems today. Various new devices and technologies continue to be developed and introduced. Vibrating orifice is one of them. The critical issue of vibrating orifice technology is the fabrication of micro-nozzles. Traditional technique to fabricate these nozzles is to use dry etching method, which tends to be expensive and inconvenient for mass production. Other two optional fabrication …


A Portable Phonatory Feedback Device For Patients With Speech Disorders, Richie Sajan Jan 2010

A Portable Phonatory Feedback Device For Patients With Speech Disorders, Richie Sajan

LSU Master's Theses

Vocal intensity-related speech disorders such as dysarthria and vocal nodules can limit quality of life and reduce the patient’s ability to interact with family, socialize, or pursue employment. Behavioral speech therapies exist to address these issues but have limited effectiveness because they are expensive and clinic-based. The ability to monitor vocal intensity outside of the clinical setting will greatly aid in the treatment of these speech disorders, enabling patients to make quicker progress by reinforcing techniques learned in the clinic. The Voice Volume Monitor (VVM) is a portable and cost-effective therapeutic aid designed for this purpose, providing real-time feedback regarding …


A Simulation Study Of Factors That Affect Pressure Control During Kick Circulation In Managed Pressure Drilling Operations, Jose Eduardo Eduardo Chirinos Jan 2010

A Simulation Study Of Factors That Affect Pressure Control During Kick Circulation In Managed Pressure Drilling Operations, Jose Eduardo Eduardo Chirinos

LSU Master's Theses

An university-industry consortium has been studying alternative well control procedures to be used for kicks taken during managed pressure drilling (MPD) operations using the constant bottom hole pressure (CBHP) method. The CBHP method of MPD allows more precise control of wellbore pressure than conventional drilling. MPD surface equipment allows more alternatives for controlling a kick and may support faster detection of kicks and losses which can reduce the severity of a well control event. Nevertheless, the elimination of well control incidents cannot be guaranteed, and the uncertainty in downhole drilling margins are not reduced by adopting MPD methods. The primary …


X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos Jan 2010

X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos

LSU Doctoral Dissertations

Synthetic fuels derived from methane, coal or biomass are essential in addressing future transportation fuel demands which are expected to exceed petroleum-derived capacities. The Fischer-Tropsch synthesis (FTS) is the most studied technique for the conversion of coal or biomass-derived syngas into transportation fuels. Fe-based catalysts are typically used for the FTS of biomass and/or coal-derived syngas due to: the relatively low cost of iron, water-gas shift activity, and low methane selectivity at industrial FTS conditions. Fe/Cu/SiO2 Fischer-Tropsch catalysts promoted with Cr, Mn, Mo, W, or Zr were studied in-situ, using Fe K-edge TPR XANES (temperature programmed reduction X-ray absorption near-edge …


Modeling And Simulation For Shape Memory Polymer Based Self-Healing Syntactic Foam, Wei Xu Jan 2010

Modeling And Simulation For Shape Memory Polymer Based Self-Healing Syntactic Foam, Wei Xu

LSU Doctoral Dissertations

Syntactic foams, renowned for their low density and high mechanical properties, are enjoying continuing growth in various civilian and military sectors. However, like laminated composites, foam cored structures are vulnerable to impact damages and suffering from inabilities in repairing macro-scale cracks. A self-healing mechanism for structural damage is genuinely desired. A recent development in self-healing structural damage is a two-step close then heal (CTH) scheme proposed by Li and Nettles [1] and elucidated by Li and Uppu [2], by mimicking the self-healing process of human skin. This concept has been further demonstrated in Nji and Li’s work [3] that a …