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Impact Of Static Flexion Duration On The Development Of A Neuromuscular Disorder Of The Lumbar Spine, Rebecca Victoria Labry
Impact Of Static Flexion Duration On The Development Of A Neuromuscular Disorder Of The Lumbar Spine, Rebecca Victoria Labry
LSU Master's Theses
Many occupational groups work under adverse conditions in which their spinal columns are fully flexed under load for substantial periods of time. This study was designed to determine the response of the lumbar spine to a static load of a substantial duration under a range of load magnitudes. The impact of static loads of 20, 40 and 60N were applied over 30 min flexion, 10 min rest, and 30 min flexion (for a total of one hour exposure) followed by a 7 h rest. Lumbar viscoelastic creep (laxity) and reflex electromyographic (EMG) activity were monitored over both flexion periods and …
Color, Texture And Rehydration Characteristics Of Ohmically Treated Sweet Potatoes, Sireesha Bhattiprolu
Color, Texture And Rehydration Characteristics Of Ohmically Treated Sweet Potatoes, Sireesha Bhattiprolu
LSU Master's Theses
Ohmic heating has been shown to affect the drying rate and texture of foods. This research was designed to determine the effect of ohmic heating on rehydration, color and texture properties of sweet potatoes. Three combinations: 60Hz, 40V, 60Hz, 60V and 1Hz, 40V were applied to ohmically heat sweet potato cubes. The ohmic treated cubes and untreated cubes or controls were stored for six days in four different %relative humidities of 11.15%, 32.73%, 57.70% and 75.32%. Results showed that there was no significant difference in the rehydration properties of ohmic treated samples and control samples. The % moisture gain varied …
Mesoscopic Simulation Of Abnormal Grain Growth, Rakesh Kumar Behera
Mesoscopic Simulation Of Abnormal Grain Growth, Rakesh Kumar Behera
LSU Master's Theses
Grain growth is the process that takes place during annealing of polycrystalline materials; its major feature is a systematic increase in grain size. Two different types of grain growth can be distinguished: the normal and abnormal grain growth. During normal grain growth, the microstructure exhibits a uniform increase in grain size with time and the grain size distribution follows the log-normal distribution with the grain sizes ranging from 0 - 2.2 times the average grain size (R). On the contrary, when the abnormal grain growth is the dominant mechanism, there are certain grains (abnormal grains) in the microstructure that grow …
Design And Performance Of Electric Shock Absorber, Oly D. Paz
Design And Performance Of Electric Shock Absorber, Oly D. Paz
LSU Master's Theses
The electric shock absorber is a device that converts the kinetic energy of an oscillating object into electric energy. This kinetic energy is normally dumped in a form of thermal energy in a conventional, mechanical shock absorber. The electric shock absorber consists of a permanent magnet linear synchronous generator (PMLSG), a spring, and an electric energy accumulator. The major goal of the project is to design and analyze the operation of an electric shock absorber. In order to define the initial requirements that the electric shock absorber has to satisfy, the construction and performance of currently used shock absorbers were …
Development Of Resilient Modulus Prediction Models For Base And Subgrade Pavement Layers From In Situ Devices Test Results, Ravindra Gudishala
Development Of Resilient Modulus Prediction Models For Base And Subgrade Pavement Layers From In Situ Devices Test Results, Ravindra Gudishala
LSU Master's Theses
Currently, the design of flexible pavements is generally conducted based on static properties such as California Bearing Ratio and soil support value. These properties do not represent the actual response of the pavement layers under traffic loadings. Recognizing this deficiency, the current and the 2002 mechanistic –empirical guide for design of pavement structures recommended the use of resilient modulus for characterizing the base and subgrade soil and for the design of flexible pavements. The objective of this study was to develop models to estimate the resilient modulus of base and subgrade soils from in situ test devices. Two types of …
First Order Sigma-Delta Modulator Of An Oversampling Adc Design In Cmos Using Floating Gate Mosfets, Syam Prasad Sbs Kommana
First Order Sigma-Delta Modulator Of An Oversampling Adc Design In Cmos Using Floating Gate Mosfets, Syam Prasad Sbs Kommana
LSU Master's Theses
We report a new architecture for a sigma-delta oversampling analog-to-digital converter (ADC) in which the first order modulator is realized using the floating gate MOSFETs at the input stage of an integrator and the comparator. The first order modulator is designed using an 8 MHz sampling clock frequency and implemented in a standard 1.5µm n-well CMOS process. The decimator is an off-chip sinc-filter and is programmed using the VERILOG and tested with Altera Flex EPF10K70RC240 FPGA board. The ADC gives an 8-bit resolution with a 65 kHz bandwidth.
Heat/Mass Transfer In Smooth And Ribbed Rectangular Serpentine Passages Of Different Aspect Ratio's And Orientation, Peeyush Agarwal
Heat/Mass Transfer In Smooth And Ribbed Rectangular Serpentine Passages Of Different Aspect Ratio's And Orientation, Peeyush Agarwal
LSU Master's Theses
An experimental study of heat/mass transfer in rectangular smooth and ribbed serpentine passages with and without rotation in two different aspect ratios (1:4 and 4:1) channel is performed for two different orientations of the test section (90-degree and 45-degree). The Reynolds number is varied in the range of 5,000 to 40,000 and rotation numbers in the range of 0-0.12. Such passages are encountered close to the mid-chord sections or towards the trailing edge of the turbine blade. Two different configurations of the Normal ribs (e/Dh=0.3125, P/e=8 and e/Dh=0.156, P/e=11.2) are placed on the leading and the …
An Evaluation Of Methods Used To Obtain The Railroad Preemption Queue Clearance Time, Deeangela Renee Kenon
An Evaluation Of Methods Used To Obtain The Railroad Preemption Queue Clearance Time, Deeangela Renee Kenon
LSU Master's Theses
Because of the potential for serious train-vehicle accidents at or near railroad-highway grade crossings, preemption of traffic signals is a very important supplement to an active warning system. Preemption is the transfer of normal signal phasing to a special control mode with the purpose of clearing any vehicles that are queued within the dynamic envelope as the train approaches, and prohibiting signal phases that would allow additional vehicles in the track area while the train is present. The focus of this research was the determination of the Clear Track Green Interval (or the Queue Clearance Time). The clear track green …
Probabilistic Risk Assessment Method For Prioritization Of Risk Factors, Jay Tarakkumar Shah
Probabilistic Risk Assessment Method For Prioritization Of Risk Factors, Jay Tarakkumar Shah
LSU Master's Theses
Risk management involves assessing the risk sources and designing strategies and procedures to mitigate those risks to an acceptable level. Measurement of risk factors plays an important role in the assessment of risk. This research proposes to develop risk assessment frameworks and mathematical model (Probabilistic Risk Assessment model) identify the risk factors. Quantification and prioritization of risk factors will help to design controls, resource allocation policies and minimize the total cost using the Cost Minimization model. The proposed models are applied to a complex system that is representative of actual business situations.
Metal-Doped Rare Earth Oxide Catalysts For Condensations To Ketones, Arvind Karkal Bhat
Metal-Doped Rare Earth Oxide Catalysts For Condensations To Ketones, Arvind Karkal Bhat
LSU Master's Theses
Metal-doped supported rare earth oxide catalysts were examined to determine their suitability for the decarboxylative condensation of two carboxylic acids to produce ketones. The catalysts were characterized based on chemisorption tests, coke analysis using thermo-gravimetric analysis and X-ray absorption spectroscopy. Effect of catalyst particle size on rate of reaction was studied for various supported cerium oxide catalysts. Catalysts were tested for activity, selectivity, and stability using isothermal fixed bed reactors. Optimal operating conditions for the production of diisopropyl ketone and methyl nonyl ketone were determined. It was found that supported cerium oxide catalysts effectively catalyzed the condensation of isobutyric acid …
Synthesis, Characterization And Tribological Behavior Of Nitrogen-Doped Chromium-Diamond-Like Carbon Nanocomposite Thin Films, Sunil Kumar Pal
Synthesis, Characterization And Tribological Behavior Of Nitrogen-Doped Chromium-Diamond-Like Carbon Nanocomposite Thin Films, Sunil Kumar Pal
LSU Master's Theses
Diamond-like carbon (DLC) films have been extensively studied for more than two decades due to their highly attractive properties. These films exhibit unique mechanical, chemical and electronic properties and thus, possess great potential for applications in tribology. However, two drawbacks in the DLC films are high level of internal stress developed during growth preventing deposition of thick films and low thermal stability. Synthesis of Me-DLC (Cr-DLC and N-doped Cr-DLC) presents a way to overcome these drawbacks. In the present study, DLC, Cr-DLC and N-doped Cr-DLC films were deposited on Si substrate using a hybrid Plasma assisted CVD/PVD process. Film characterization …
Analysis And Evaluation Of A Bioengineered Submerged Breakwater, Matthew Dwain Campbell
Analysis And Evaluation Of A Bioengineered Submerged Breakwater, Matthew Dwain Campbell
LSU Master's Theses
Louisiana's coastline has received national attention due to rapid erosion rates estimated from approximately 60 to 100 square kilometers per year. The disappearance of coastal areas jeopardizes public and private infrastructure, property values, aquatic ecosystems, and standards of living. In order to resolve the erosion problem, innovative solutions have been explored that may improve effectiveness and cost efficiency. This research involves a technology, termed an "oysterbreak," which is a bioengineered submerged breakwater. This structure promotes oysters to form a dense structure that dissipates wave energy. Since the structure is biologically dominated, initial material use is modest. The oysterbreak was evaluated …
Small And Large Strain Monitoring Of Unsaturated Soil Behavior By Means Of Multiaxial Testing And Shear Wave Propagation, Oscar F. Porras Ortiz
Small And Large Strain Monitoring Of Unsaturated Soil Behavior By Means Of Multiaxial Testing And Shear Wave Propagation, Oscar F. Porras Ortiz
LSU Doctoral Dissertations
The deformation and strength behavior of dry and saturated soils is controlled by the effective stresses as defined by Terzaghi. However, Terzaghi’s definition of the effective stresses fails for unsaturated soils, as capillarity force influence is also important. The effects of capillarity forces in soil are evaluated by the concept of matrix suction. Several techniques are used to evaluate soil suction however their applications involve difficult calibrations and tedious methodology. Furthermore, suction is a microscopic property and it is influenced by interparticle soil attraction, which can change by sampling disturbance. This research program evaluates the effect of suction on stiffness …
Stabilization Of Flue Gas Desulfurization Sludge For Application In Marine Environments, Tej Kour
Stabilization Of Flue Gas Desulfurization Sludge For Application In Marine Environments, Tej Kour
LSU Master's Theses
Flue Gas Desulfurization sludge (FGD, CaSO4·2H2O, CaSO3·1/2H2O) is a waste by-product produced when sorbent slurry is passed through wet scrubbers. FGD contains higher concentrations of Ca, S, Si, Fe, Al and Br making it of great environmental concern. Presently only 16% of 24 million metric tons (MT) of FGD sludge produced is being recycled; the rest is disposed in landfills. This research was focused towards stabilizing FGD sludge with Portland Type II cement and Class C fly ash to produce lightweight fill material to be used in the construction of coastal devices. The specific objectives included the development of a …
Testing A Cmos Operational Amplifier Circuit Using A Combination Of Oscillation And Iddq Test Methods, Pavan K. Alli
Testing A Cmos Operational Amplifier Circuit Using A Combination Of Oscillation And Iddq Test Methods, Pavan K. Alli
LSU Master's Theses
This work presents a case study, which attempts to improve the fault diagnosis and testability of the oscillation testing methodology applied to a typical two-stage CMOS operational amplifier. The proposed test method takes the advantage of good fault coverage through the use of a simple oscillation based test technique, which needs no test signal generation and combines it with quiescent supply current (IDDQ) testing to provide a fault confirmation. A built in current sensor (BICS), which introduces insignificant performance degradation of the circuit-under-test (CUT), has been utilized to monitor the power supply quiescent current changes in the CUT. The testability …
Optimal Test Case Selection For Multi-Component Software System, Praveen Babu Kysetti
Optimal Test Case Selection For Multi-Component Software System, Praveen Babu Kysetti
LSU Master's Theses
The omnipresence of software has forced upon the industry to produce efficient software in a short time. These requirements can be met by code reusability and software testing. Code reusability is achieved by developing software as components/modules rather than a single block. Software coding teams are becoming large to satiate the need of massive requirements. Large teams could work easily if software is developed in a modular fashion. It would be pointless to have software that would crash often. Testing makes the software more reliable. Modularity and reliability is the need of the day. Testing is usually carried out using …
Development Of A Neural Network Approach For The Assessment Of The Performance Of Traffic Sign Retroreflectivity, Nagajyothi Swargam
Development Of A Neural Network Approach For The Assessment Of The Performance Of Traffic Sign Retroreflectivity, Nagajyothi Swargam
LSU Master's Theses
The goal of the research was to develop a new predictive tool for assessing the performance of traffic sign retroreflectivity and to compare the developed tool with the existing linear regression models. Retroreflectivity decreases as sign sheeting ages. Currently Louisiana Department of Transportation and Development (LADOTD) replace signs with low reflectivity based on driver complaints. This practice might have resulted in premature sign replacement (removal of signs with several years of in-service life still remaining) or in non-replacement of signs that are not in compliance with LADOTD minimum reflectivity standards. In this study, both neural network models and regression models …
Development And Integration Of New Processes Consuming Carbon Dioxide In Multi-Plant Chemical Production Complexes, Sudheer Indala
Development And Integration Of New Processes Consuming Carbon Dioxide In Multi-Plant Chemical Production Complexes, Sudheer Indala
LSU Master's Theses
New, energy-efficient and environmentally acceptable, catalytic processes have been identified that can use excess high purity CO2 as a raw material from the sources available in a chemical production complex. The chemical complex in the lower Mississippi River Corridor has been used to show how these new plants can be integrated into this existing infrastructure using the Chemical Complex and Cogeneration Analysis System. Eighty six published articles of laboratory and pilot plant experiments were reviewed that describe new methods and catalysts to use CO2 for producing commercially important products. Reactions have been categorized as hydrogenation reactions; hydrocarbon synthesis …
Iddq Testing Of A Cmos First Order Sigma-Delta Modulator Of An 8-Bit Oversampling Adc, Anand K. Chamakura
Iddq Testing Of A Cmos First Order Sigma-Delta Modulator Of An 8-Bit Oversampling Adc, Anand K. Chamakura
LSU Master's Theses
This work presents IDDQ testing of a CMOS first order sigma-delta modulator of an 8-bit oversampling analog-to-digital converter using a built-in current sensor [BICS]. Gate-drain, source-drain, gate-source and gate-substrate bridging faults are injected using fault injection transistors. All the four faults cause varying fault currents and are successfully detected by the BICS at a good operation speed. The BICS have a negligible impact on the performance of the modulator and an external pin is provided to completely cut-off the BICS from the modulator. The modulator was designed and fabricated in 1.5 μm n-well CMOS process. The decimator was designed on …
Zooplankton Visualization System: Design And Real-Time Lossless Image Compression, Dattatreya Reddy Tetala Satya Surya
Zooplankton Visualization System: Design And Real-Time Lossless Image Compression, Dattatreya Reddy Tetala Satya Surya
LSU Master's Theses
In this thesis, I present a design of a small, self-contained, underwater plankton imaging system. I base the imaging system’s design on an embedded PC architecture based on PC/104-Plus standards to meet the compact size and low power requirements. I developed a simple graphical user interface to run on a real-time operating system to control the imaging system. I also address how a real-time image compression scheme implemented on an FPGA chip speeds up image transfer speeds of the imaging system. Since lossless compression of the image is required in order to retain all image details, I began with an …
Numerical And Experimental Investigation Of Transport Processes In Biological Systems, Yimeng He
Numerical And Experimental Investigation Of Transport Processes In Biological Systems, Yimeng He
LSU Master's Theses
This thesis focuses on optimization techniques for transport process during the cryopreservation of biological systems. In the first part of this thesis, a well established shape independent Differential Scanning Calorimeter (DSC) technique was used to measure the dehydration response during freezing of Pacific oyster sperm cells. Volumetric shrinkage during freezing of diploid and tetraploid pacific oyster sperm cell suspensions was obtained at cooling rates of 5 and 20 ˚C/min in the presence of extracellular ice and CPAs. By fitting a model of water transport to the experimentally obtained volumetric shrinkage data the best fit membrane permeability parameters (Lpg and …
Travel Time Tomographic Imaging Of The Distribution Of The Effective Stress In Clean Sand Under A Model Footing, William M. Tanner
Travel Time Tomographic Imaging Of The Distribution Of The Effective Stress In Clean Sand Under A Model Footing, William M. Tanner
LSU Master's Theses
The use of high-speed data acquisition systems, inexpensive and reliable transducers, and better models of interpretation have combined to make elastic wave tomographic imaging of geotechnical engineering systems easier to accomplish both in the laboratory and in the field. An important application of these developments is that the evaluation of states of effective stress in soils using images of elastic wave velocity distribution. As a consequence, it is possible to experimentally estimate the state of induced and in-situ effective stresses and to compare these results with established models of stress distribution based on the theory of elasticity (e.g., Boussinesq’s solution). …
A Novel Mechanical Seal Design With Superior Thermal Characteristics, Anoop Kumar Somanchi
A Novel Mechanical Seal Design With Superior Thermal Characteristics, Anoop Kumar Somanchi
LSU Master's Theses
A mechanical face seal is an important component of variety of pumps used in chemical, petrochemical and process industry. The primary function of a mechanical seal is to prevent leakage of the process fluid from the pump housing and shaft to the environment. The factors that affect the performance of a mechanical seal to leak are friction, wear and its thermal characteristics. Improving upon the thermal characteristics of a mating ring in a mechanical seal would enhance its performance. Implanting a heat exchanger in the mating ring hold great promise for improving the performance of mechanical seals from the viewpoint …
Design And Development Of A Process Control Temperature System For Eastern Oyster Crassostrea Virginica Research, Praveen Kolar
Design And Development Of A Process Control Temperature System For Eastern Oyster Crassostrea Virginica Research, Praveen Kolar
LSU Master's Theses
A process-control temperature system was designed and developed for facilitating somatic cell research on eastern oyster Crassostrea virginica. The system consisted of sixteen independent tanks capable of individual temperature regimes controlled by a central computer. Food grade 250-L tanks were used to hold 60 oysters per tank. Each tank was equipped with heating and cooling mechanisms. Immersion heaters were used for heating and a pump and a stainless steel heat exchangers immersed in chilled water (~ 7°C) were used for cooling. Type-T thermocouples along with a CIOEXP32 multiplexer board (Measurement Computing Inc.) were used to measure water temperatures. Control was …
Online Heat Transfer Measurement And Analysis For Sugar Mill Evaporators, David Timothy Solberg
Online Heat Transfer Measurement And Analysis For Sugar Mill Evaporators, David Timothy Solberg
LSU Master's Theses
Fouling and scaling in evaporators has been an area of great interest to raw sugar mills for a number of years and many of the mechanisms causing the scale and the rates of scaling are unknown. In an attempt to quantify the scaling rates and measure the scaling, an online model has been developed to model a system of evaporators. Monitoring the heat transfer coefficient as a function of time enabled measurement of the scaling rate by monitoring the heat transfer coefficient as it decreased with time. It is assumed that the scaling on the juice side of the evaporators …
Evaluation Of New Methods For Processing Drilling Data To Determine The Cause Of Changes In Bit Performance, Jaime Solano
Evaluation Of New Methods For Processing Drilling Data To Determine The Cause Of Changes In Bit Performance, Jaime Solano
LSU Master's Theses
Drilling operations represent the major cost in finding and developing new petroleum reserves. Poor drilling performance when drilling deep shale and strong rocks, as evidenced by slow rate of penetration (ROP), has a significant detrimental impact on drilling costs. Also, it has been concluded that bit balling is the main cause of low ROP when drilling deep, clay-rich shale with water-based mud. In addition, it is estimated that a potential saving in drilling cost of hundreds of millions of dollars a year can be obtained if bit balling is mitigated and ROP is improved. Several methods have been developed in …
Performance Assessment Of Coated Cemented Carbide Tools In Turning Aisi 1018 Steel, Mohamad Nouilati
Performance Assessment Of Coated Cemented Carbide Tools In Turning Aisi 1018 Steel, Mohamad Nouilati
LSU Master's Theses
In this study, the machining performance of a series of commercially available coated tungsten based cemented carbides, with 55o diamond shape, were investigated during finish turning of AISI 1018 steel under dry conditions. The inserts tested had a coating of TiN, Al2O3, TiN/Al2O3 and TiC/Al2O3/TiN respectively. For comparison, uncoated cemented tungsten carbide was also tested under the same cutting conditions. The coated tools exhibited superior wear resistance over the uncoated tool. The TiC/Al2O3/TiN coated tool had the lowest flank wear due to the high abrasive resistance of the TiC layer. The Al2O3 coated tool showed superior wear-resistance over the TiN/Al2O3 …
Numerical Simulation And Field Verification Of Inclined Piezocone Penetration Test In Cohesive Soils, Lei Wei
Numerical Simulation And Field Verification Of Inclined Piezocone Penetration Test In Cohesive Soils, Lei Wei
LSU Doctoral Dissertations
A large strain finite element analysis is performed to analyze the effect of soil anisotropy on the inclined piezocone penetration test in normally consolidated cohesive soils. The piezocone penetration is numerically simulated using the commercial finite element code ABAQUS. The saturated clay is modeled as a two-phase material and the effective stress principle is used to describe its behavior. A frictional contact interface utilizing Mohr-Coulomb's theory was chosen to represent interactions between the surface of the cone and the soil. The Anisotropic Modified Cam Clay Model (AMCCM) by Dafalias (1987) was chosen and implemented into ABAQUS through user subroutine UMAT. …
Chemical Production Complex Optimization, Pollution Reduction And Sustainable Development, Aimin Xu
Chemical Production Complex Optimization, Pollution Reduction And Sustainable Development, Aimin Xu
LSU Doctoral Dissertations
The objective of this research is to propose, develop and demonstrate chemical production complex optimization to determine the optimal configuration of chemical plants in a superstructure of possible plants. The Chemical Complex Analysis System is a new methodology that has been developed to determine the best configuration of plants in a chemical production complex based on the AIChE Total Cost Assessment (TCA) for economic, energy, environmental and sustainable costs. All new, energy-efficient, and environmentally acceptable plants using greenhouse gases that can produce potentially commercial products designed with HYSYS were integrated into the chemical complex using the System. The optimum configuration …
Development Of Dynamic Travel Demand Models For Hurricane Evacuation, Haoqiang Fu
Development Of Dynamic Travel Demand Models For Hurricane Evacuation, Haoqiang Fu
LSU Doctoral Dissertations
Little attention has been given to estimating dynamic travel demand in transportation planning in the past. However, when factors influencing travel are changing significantly over time – such as with an approaching hurricane - dynamic demand and the resulting variation in traffic flow on the network become important. In this study, dynamic travel demand models for hurricane evacuation were developed with two methodologies: survival analysis and sequential choice model. Using survival analysis, the time before evacuation from a pending hurricane is modeled with those that do not evacuate considered as censored observations. A Cox proportional hazards regression model with time-dependent …