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Overview Of Cogeneration At Lsu, Robert,Jr. Buckley Jan 2006

Overview Of Cogeneration At Lsu, Robert,Jr. Buckley

LSU Master's Theses

Cogeneration (or Combined Heat and Power) continues to gain importance in power production because of its high efficiency, environmental friendliness, and flexibility. Louisiana State University (LSU) recently began operation of a new 20 MW cogeneration system. This new facility can serve as a useful learning tool for chemical and mechanical engineering students throughout their education at LSU. The goal of this project is to develop educational modules utilizing the cogeneration system which have industrial significance. Educational modules will include: a comparison of ideal gas versus real gas thermodynamics for a cogeneration optimization problem, a cogeneration data reconciliation problem, and a …


Automatic Active Contour Modelling And Its Potential Application For Non-Destructive Testing, Srinath Vepathur Sitaraman Jan 2006

Automatic Active Contour Modelling And Its Potential Application For Non-Destructive Testing, Srinath Vepathur Sitaraman

LSU Master's Theses

Active contouring techniques are very useful in medical imaging, digital mapping, non-destructive ultrasonic evaluation, etc. Therefore, we try to explore and investigate the advanced automatic active contouring methods, which can benefit the aforementioned applications. In this thesis work, we study the automatic active contour models adopted for the object characterization, whose extensions could include the potential defect analysis in the ultrasonic non-destructive testing. The active contouring scheme (also called a snake) or an energy minimizing spline, is an algorithm which is very sensitive to the manually marked initial points, and thereby requires an expertly operation. Therefore, we make new research …


Calibration Of Flexural Design Of Concrete Members Reinforced With Frp Bars, Sujata Nandkumar Kulkarni Jan 2006

Calibration Of Flexural Design Of Concrete Members Reinforced With Frp Bars, Sujata Nandkumar Kulkarni

LSU Master's Theses

Fiber Reinforced Polymer (FRP) composites have been increasingly accepted in the construction industry as a promising substitute for steel. Bridge deck deterioration is one of the most common deficiencies in a bridge system. The use of FRP bars as reinforcement for concrete bridge decks provides a potential for increased service life, economic, and environmental benefits. This research presents the development of resistance models for concrete members (beams and slabs) reinforced with FRP bars (FRP-RC), for carrying out reliability analysis. The scope of this model is limited to the flexural behavior only; i.e. the failures are not shear failure and debonding. …


Compiler Assisted Cache Prefetch Using Procedure Call Hierarchy, Sheela A. Doshi Jan 2006

Compiler Assisted Cache Prefetch Using Procedure Call Hierarchy, Sheela A. Doshi

LSU Master's Theses

Microprocessor performance has been increasing at an exponential rate while memory system performance improved at a linear rate. This widening difference in performances is increasingly rendering advances in computer architecture less useful as more instructions spend more time waiting for data to be fetched from the memory after a cache miss. Data prefetching is a technique that avoids some cache misses by bringing data into the cache before it is actually needed. Different approaches to data prefetching have been developed, however existing prefetch schemes do not eliminate all cache misses and even with smaller cache miss ratio, miss latency remains …


Numerical Solution Of Flow Resistance In Outflow Pathway And Intravitreal Drug Delivery In Vitrectomised Eyes, Jyoti Gururaj Kathawate Jan 2006

Numerical Solution Of Flow Resistance In Outflow Pathway And Intravitreal Drug Delivery In Vitrectomised Eyes, Jyoti Gururaj Kathawate

LSU Master's Theses

In this study, numerical computations of the ocular fluid dynamics in a human eye are presented with a perspective of understanding the mechanisms of increased flow resistance. In the present study, the TM is represented as a multilayered-graded porous structure with specific pore size and void fraction. The flow patterns and pressure distribution in anterior chamber are analyzed to delineate key flow mechanism; the shear stresses on the lens, iris and IW of SC are also examined to locate the maximum values. Inside the human eye, the largest pressure drop occurs across JCT and IW of SC. The highest pressure …


Electrodeposition Of Cocu Nanostructures, Yutong Li Jan 2006

Electrodeposition Of Cocu Nanostructures, Yutong Li

LSU Doctoral Dissertations

Electrodeposition is a key component in the microelectronic industry because it has the following advantages: low cost, easy operation and the capability to deposit into irregular geometries such as recessed and curved areas. In this dissertation, CoCu alloys were investigated to fabricate multilayers, microdevices and microposts. All of these multilayer structures were composed of nanometric copper and cobalt-rich layers in order to obtain magnetoresistance, a phenomenon where the resistance of multilayer structures decreases with increases of external magnetic field. An investigation was carried out in order to evaluate appropriate plating conditions during multilayered thin film deposition, with the aim to …


Physical Model Study Of The Effects Of Wettability And Fractures On Gas Assisted Gravity Drainage (Gagd) Performance, Wagirin Ruiz Paidin Jan 2006

Physical Model Study Of The Effects Of Wettability And Fractures On Gas Assisted Gravity Drainage (Gagd) Performance, Wagirin Ruiz Paidin

LSU Master's Theses

The Gas-Assisted Gravity Drainage (GAGD) process was developed to take advantage of the natural segregation of injected gas from crude oil in the reservoir. It consists of placing a horizontal producer near the bottom of the reservoir and injecting gas using existing vertical wells. As the injected gas rises to the top to form a gas cap, oil and water drain down to the horizontal producer. Earlier experimental work using a physical model by Sharma had demonstrated the effectiveness of the GAGD process in improving the oil recovery when applied in water-wet porous media. The current research is an extension …


Effect Of Repetitions On Static And Dynamic Strength, Sai Chaitanya Reddy Bogolu Jan 2006

Effect Of Repetitions On Static And Dynamic Strength, Sai Chaitanya Reddy Bogolu

LSU Master's Theses

The objective of this study was to investigate the effect of repetitions on static and dynamic strength. The study is divided into two parts, the first part investigated static and dynamic strength during one, three and six repetitions per minute, and the second part of the study analyzed dynamic strength data collected using the Multiaxial Multipurpose Isokinetic Dynamometer. The study comprised of dynamic strength test data at three speeds of one, five and ten inch per second. Five male subjects participated in the first part of the study, and the results were analyzed by plotting a time series to observe …


Exploring The Hot-Carrier Effect On The Wireless Transceivers, Sameer R. Herlekar Jan 2006

Exploring The Hot-Carrier Effect On The Wireless Transceivers, Sameer R. Herlekar

LSU Doctoral Dissertations

Phase noise can be regarded as the most severe cause of performance degradation in the wireless communication systems. The hot-carriers (HCs), found in the CMOS synchronization circuits, are the high-energy charge carriers that degrade the MOSFET devices’ performance by increasing the threshold voltage required to operate the MOSFETs. The HC effect manifests itself as the phase noise whose level increases with the continued MOSFET operation and such increases result in the performance degradation of the voltage-controlled oscillator (VCO) built on the MOSFETs. The HC effect is particularly evident in the short-channel MOSFET devices. In this dissertation, we analyze the wireless …


Alpha-Tocopherol: Extraction From Rice Bran By Microwave-Assisted Method, And Entrapment And Release From Polymeric Nanoparticles, Imola G. Zigoneanu Jan 2006

Alpha-Tocopherol: Extraction From Rice Bran By Microwave-Assisted Method, And Entrapment And Release From Polymeric Nanoparticles, Imola G. Zigoneanu

LSU Master's Theses

The purpose of this study was two-fold, 1) to extract and quantify vitamin E components from rice bran using microwave extraction, to determine the antioxidant activity of the rice bran oil, and the effect of solvent and temperature on vitamin E components and oil yield, and 2) to entrap alpha-tocopherol into polymeric nanoparticles, to characterize the nanoparticles in terms of morphology, size and size distribution, zeta potential, entrapment efficiency, and amount of residual PVA associated with the nanoparticles, as well as to study the release of alpha-tocopherol from PLGA nanoparticles. Microwave-assisted extraction was an efficient method for the extraction of …


Intercarrier Interference Suppression For The Ofdm Systems In Time-Varying Multipath Fading Channels, Xiaozhou Huang Jan 2006

Intercarrier Interference Suppression For The Ofdm Systems In Time-Varying Multipath Fading Channels, Xiaozhou Huang

LSU Doctoral Dissertations

Due to its spectral efficiency and robustness over the multipath channels, orthogonal frequency division multiplexing (OFDM) has served as one of the major modulation schemes for the modern communication systems. In the future, the wireless OFDM systems are expected to operate at high carrier-frequencies, high speed and high throughput mobile reception, where the fasting time-varying fading channels are encountered. The channel variation destroys the orthogonality among the subcarriers and leads to the intercarrier interference (ICI). ICI poses a significant limitation to the wireless OFDM systems. The aim of this dissertation is to find an efficient method of providing reliable communication …


A Plasticity-Damage Model For Plain Concrete, Umit Cicekli Jan 2006

A Plasticity-Damage Model For Plain Concrete, Umit Cicekli

LSU Doctoral Dissertations

A plastic-damage model for plain concrete is developed in this work. The model uses two different yield criteria: one for plasticity and one for damage. In order to account both for compression and tension loadings, the damage criterion is divided into two parts: one for compression and a second for tension. The superscripts (+) and (-) in this work are used to represent tension and compression cases, respectively. The total stress is decomposed into tension and compressions components. The total strain is decomposed into elastic and plastic parts. The strain equivalence concept is used such that the strains in the …


Characterization And Tribological Behavior Of Diamond-Like Carbon And Nitrogen-Doped Diamond-Like Carbon Thin Films, Krishna Chaitanya Kadiyala Jan 2006

Characterization And Tribological Behavior Of Diamond-Like Carbon And Nitrogen-Doped Diamond-Like Carbon Thin Films, Krishna Chaitanya Kadiyala

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, electrical and tribological behavior and thus, possess great potential for applications in tribology. However, the high level of internal stress developed and low thermal stability are the main drawbacks. Synthesis of nitrogen-doped DLC (N-DLC) offers the possibility of overcoming these drawbacks. In the present study, DLC and N-DLC films (with low N content) were deposited on Si substrates using a hybrid plasma-assisted CVD/PVD process. Film characterization in terms of microstructure, composition and chemical state of components …


Refurbishment Of Louisiana State University Calibration Chamber, Ardita Dushi Jan 2006

Refurbishment Of Louisiana State University Calibration Chamber, Ardita Dushi

LSU Master's Theses

This thesis focuses on the refurbishment of Louisiana State University calibration chamber. The testing equipments were checked and connected together to complete the calibration chamber system. The data acquisition system was upgraded to National Instruments (NI) SCXI system. Therefore, a compatible computer program language in LabVIEW was developed. LabVIEW is a programming language developed by NI that reads the data from the instruments, displays the data in graphical form, calculates the desired parameters, commands the transducer to apply the required pressure to the specimen, and saves the data at the desired frequency. The Anisotropic Modified Cam Clay Model (AMCCM) following …


A Thermodynamic Model For Wear In Sliding Contact, Susheel Brahmeshwarkar Jan 2006

A Thermodynamic Model For Wear In Sliding Contact, Susheel Brahmeshwarkar

LSU Master's Theses

Consideration of wear, an irreversible phenomenon, is a very important criterion in design. The knowledge of wear and its behavior enables one to make major considerations to conceptualize and design efficient machinery components with enhanced performance and reliability. The present work deals with the introduction of a novel approach of correlating wear with the thermodynamic properties of the system. The approach involves relating wear to thermodynamic entropy flow in the system using the laws of thermodynamics. This relation is verified experimentally and theoretically by considering a sliding contact in a disk-on-disk configuration for two sets of contacting materials namely Bronze …


Pulsed Vertical Jet In Cross Flow At Mean Blowing Ratios 0.35 And 0.45, Pierre-Emmanuel Jacques Joseph Bouladoux Jan 2006

Pulsed Vertical Jet In Cross Flow At Mean Blowing Ratios 0.35 And 0.45, Pierre-Emmanuel Jacques Joseph Bouladoux

LSU Master's Theses

This thesis deals with a pulsed vertical jet transverse to a cross flow (U=1.6m/s) at mean blowing ratios 0.35 and 0.45. First the reasons of this study are explained and the previous work in the field is described. Then the experimental setup, the experimental procedures and the data processing are detailed. The system (wind tunnel and jet) is characterized before studying the Jet in Cross Flow (JICF). The JICF is explored under unforced and forced conditions through LASER sheet visualizations and constant temperature anemometry (CTA) measurements using hot-wire sensors. Blowing ratios ranging from 0.150 to 0.600 are studied …


Information Analysis Of Dna Sequences, Riyazuddin Mohammed Jan 2006

Information Analysis Of Dna Sequences, Riyazuddin Mohammed

LSU Master's Theses

The problem of differentiating the informational content of coding (exons) and non-coding (introns) regions of a DNA sequence is one of the central problems of genomics. The introns are estimated to be nearly 95% of the DNA and since they do not seem to participate in the process of transcription of amino-acids, they have been termed “junk DNA.” Although it is believed that the non-coding regions in genomes have no role in cell growth and evolution, demonstration that these regions carry useful information would tend to falsify this belief. In this thesis, we consider entropy as a measure of information …


Molecular Dynamics Simulation Study Of Grain Boundary Migration In Nanocrystalline Pd, Shengyu Wang Jan 2006

Molecular Dynamics Simulation Study Of Grain Boundary Migration In Nanocrystalline Pd, Shengyu Wang

LSU Master's Theses

We present a new methodology for measuring the grain boundary mobility for curved boundaries using molecular-dynamics simulation of grain growth in a small, specifically tailored Pd nanocrystalline structure. In the model system, the boundaries move under the forces provided by their curvature and in the presence of the triple junctions. As a consequence of grain boundary migration the boundary area per unit volume is reduced and the mean grain size of grains increases with time. Our investigation shows that at elevated temperatures the activation energy for grain growth in this specifically tailored microstructure is very close to that of grain …


Erosion Control Products From Sugarcane Bagasse, Irina Dinu Jan 2006

Erosion Control Products From Sugarcane Bagasse, Irina Dinu

LSU Master's Theses

The erosion control industry uses different types of geosynthetics in order to mitigate the negative impact that erosion has on the environment. One of the most rapidly growing segments within this industry is the natural mats and blankets market. With new environmental regulations and enforcement, the demand for these natural products has considerably increased because of their biodegradability, good moisture retention, low cost and environmentally friendly image. The goal of this present work was to develop a continuous manufacturing process for sugarcane bagasse mats, which could be implemented in the local sugar mills and could provide an economic benefit to …


Study Of Particle Growth And Breakdown In Single Size Gamma Prime Distribution And High Temperature Creep In In738lc Nickel Superalloy, Arvind Kumar Dwarapureddy Jan 2006

Study Of Particle Growth And Breakdown In Single Size Gamma Prime Distribution And High Temperature Creep In In738lc Nickel Superalloy, Arvind Kumar Dwarapureddy

LSU Master's Theses

IN738LC, a nickel based superalloy has wide applications in the gas turbine engines because of its ability to retain its strength at high temperatures involved. The stability of the γ' Ni3Al (Ti, Nb) precipitate microstructure which gives the alloy its strength is very important. After an initial annealing at 1200°C for 4 hours and water quenching, a uniform distribution of single size (70nm) γ' fine precipitates is obtained. Growth of the γ' particles, their size and distribution are studied after subsequent annealing heat treatments, conducted at different temperatures for different time periods. The average precipitate size data of …


A Configurable Decoder For Pin-Limited Applications, Matthew Collin Jordan Jan 2006

A Configurable Decoder For Pin-Limited Applications, Matthew Collin Jordan

LSU Master's Theses

Pin limitation is the restriction imposed on an IC chip by the unavailability of a sufficient number of I/O pins. This impacts the design and performance of the chip, as the amount of information that can be passed through the boundary of the chip becomes limited. One area that would benefit from a reduction of the effect of pin limitation is reconfigurable architectures. In this work, we consider reconfigurable devices called Field Programmable Gate Arrays (FPGAs). Due to pin limitation, current FPGAs use a form of 1-hot decoder to select elements (one frame at a time) during partial reconfiguration. This …


Development Of An Inexpensive Guidance System For Agricultural Purposes, Goutam Jagannadha Nistala Jan 2006

Development Of An Inexpensive Guidance System For Agricultural Purposes, Goutam Jagannadha Nistala

LSU Master's Theses

Robotics is a rapidly growing technology and robots have pervaded into most of the industries. Robotics and automation are designed to remove the human factor from the labor intensive and monotonous work and thereby decrease the associated costs. The application of robotics to agriculture is fairly recent. Robotic applications in agriculture vary from autonomous row-guidance tractors to fruit picking robots. Similarly, soil testing and soil sampling is one area in agriculture where automation of tasks and the employment of an autonomous robot would be of great use to consultants and farmers employing site specific farming techniques. Soil testing is an …


Acoustic Emission Monitoring And Quantitative Evaluation Of Damage In Reinforced Concrete Members And Bridges, Archana Nair Jan 2006

Acoustic Emission Monitoring And Quantitative Evaluation Of Damage In Reinforced Concrete Members And Bridges, Archana Nair

LSU Master's Theses

A considerable proportion of highway bridges in the US, are made of reinforced concrete. The vulnerability of these structures during their long service life is a cause of major concern for civil engineers. Since there is a need to detect and recuperate the condition of the bridge structures numerous innovative non-destructive testing (NDT) techniques have come into the forefront. Of the many available technologies, acoustic emission (AE) monitoring has been the most popular non-destructive technique used on highway bridges. Acoustic emission is a passive monitoring technique. Thus, it can be appropriately used for field bridge monitoring applications. Usually AE monitoring …


[Delta] Iddq Testing Of A Cmos 12-Bit Charge Scaling Digital-To-Analog Converter, Kalyan Madhav Golla Jan 2006

[Delta] Iddq Testing Of A Cmos 12-Bit Charge Scaling Digital-To-Analog Converter, Kalyan Madhav Golla

LSU Master's Theses

This work presents design, implementation and test of a built-in current sensor (BICS) for ∆IDDQ testing of a CMOS 12-bit charge scaling digital-to-analog converter (DAC). The sensor uses power discharge method for the fault detection. The sensor operates in two modes, the test mode and the normal mode. In the test mode, the BICS is connected to the circuit under test (CUT) which is DAC and detects abnormal currents caused by manufacturing defects. In the normal mode, BICS is isolated from the CUT. The BICS is integrated with the DAC and is implemented in a 0.5 μm n-well CMOS technology. …


Performance Of Torus-Type Brushless Dc Motor With Winding Connected In Two And Three-Phase System, Dinakar Choppa Jan 2006

Performance Of Torus-Type Brushless Dc Motor With Winding Connected In Two And Three-Phase System, Dinakar Choppa

LSU Master's Theses

A torus-type permanent magnet brushless DC motor is the object of this thesis. The motor can operate with the winding connected either in two - phase or three - phase system. A comparative study of performance of the motor operating in these two systems is the objective of the thesis. To analyze the motor performance, the dynamic models of the motors operating with two - phase and three - phase motors have been proposed. The simulation of motor operation was carried out using the MATLAB/SIMULINK software package. A study of motors operation in steady state conditions has been done by …


Communication Blades: Modular Communications For Tangible And Embedded Interfaces, Karun Kumar Kallakuri Jan 2006

Communication Blades: Modular Communications For Tangible And Embedded Interfaces, Karun Kumar Kallakuri

LSU Master's Theses

Bladed Tiles is a modular hardware toolkit for building tangible and embedded interface devices. It includes “function blades” and “interaction tiles,” which can provide a flexible, inexpensive, open-ended platform for constructing a wide variety of tangible and embedded interfaces. In this paper, we propose Communication Blades. These are a class of electronic modules with varied computational capabilities for interfacing devices built using bladed tiles toolkit and also for interfacing embedded devices as adapters with external communication networks. These blades provide flexibility by offering the ability to select between different communication technologies and connectivity by providing devices with interoperability over different …


Performance Modeling Of Explosively Actuated Devices, Adam M. Braud Jan 2006

Performance Modeling Of Explosively Actuated Devices, Adam M. Braud

LSU Master's Theses

Explosively actuated devices (pin pullers, cable cutters, valves, etc) are used extensively to perform critical functions for aerospace, industrial, and defense related applications. The failure of these devices have led to a greater effort to quantify device design and performance. This thesis describes the actuation process of an explosively actuated valve, including: 1) the burning of the solid explosive HMX (C4H8N8O8) and production of its high pressure gas products, 2) the mass transfer of gas products through an actuator to an expansion volume including choked flow effects, 3) the resulting piston motion …


Grinding Wheel Condition Monitoring With Boosted Classifiers, Fengming Tang Jan 2006

Grinding Wheel Condition Monitoring With Boosted Classifiers, Fengming Tang

LSU Master's Theses

In this thesis, two data sets collected in grinding process under different cutting and wheel conditions were studied. One is the cutting forces in three directions, i.e. X, Y and Z, collected under two different cutting conditions. The other one is the acoustic emission (AE) signals collected under different wheel conditions(sharp and dull). For the goal of grinding wheel condition monitoring, the regression model with autocorrelated errors was proved to be effective and was used to extract features from signals in this study. The coefficients of the models served as the features used in the classification step that employed boosting …


Robust Fault-Tolerant Control For Aircraft Systems, Phalguna Kumar Rachinayani Jan 2006

Robust Fault-Tolerant Control For Aircraft Systems, Phalguna Kumar Rachinayani

LSU Master's Theses

The need to design controllers that guarantee both stability and performance upon the occurrence of faults has been an active area of research. To address this problem, in this thesis we present different methodologies to design robust controllers that guarantee both stability and robustness for actuator faults and uncertainties. In the first part of this thesis, we introduce the classical uncertainty formulation using Linear Fractional Transformation (LFT) and describe LFT's special cases-norm bounded and convex polytopic uncertainty descriptions. Practical methods to formulate these uncertainty structures are described. In the same spirit, formulation of faults and their modeling for robust control …


Development And Application Of Methods For Evaluation Of Hurricane Shelters, James P. Gregg Jan 2006

Development And Application Of Methods For Evaluation Of Hurricane Shelters, James P. Gregg

LSU Master's Theses

With the population of hurricane prone regions increasing, it has become more difficult to evacuate entire communities, increasing the need for hurricane shelters in coastal areas. Community officials generally use American Red Cross Standard ARC 4496 to evaluate the suitability of buildings for use as shelters.. ARC 4496 uses a least-risk process that evaluates many building and site characteristics. However, it does not address characteristics of the approaching storm and does not provide insight to the expected hazards and performance of the facility under different hurricane conditions. A new method for evaluating facilities for use as hurricane shelters is proposed. …