Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

LSU Master's Theses

Discipline
Keyword
Publication Year

Articles 901 - 930 of 1307

Full-Text Articles in Engineering

Study Of Half-Order Bod Reactions, Nicole Plauche Lirette Jan 2007

Study Of Half-Order Bod Reactions, Nicole Plauche Lirette

LSU Master's Theses

Appropriate modeling of Biochemical Oxygen Demand, BOD, is an important part of understanding the character of a wastewater. Much necessary information is gleaned and extracted from the kinetic equation chosen for modeling, especially when a BOD model is included in a dissolved oxygen model. Some information includes the ultimate level of BOD exerted, the rate the BOD demand for dissolved oxygen is exerted, and the critical time at which the minimum level of dissolved oxygen occurs. Although widely used, the first-order kinetic BOD model is not suited for all situations. In some instances, as is the case with constituents found …


Transcendental Eigenvalue Problems Associated With Vibration, Buckling And Control, Jayaram Subramanian Jan 2007

Transcendental Eigenvalue Problems Associated With Vibration, Buckling And Control, Jayaram Subramanian

LSU Master's Theses

The static and dynamic analysis of structures requires us to obtain solutions of their espective governing differential equations subject to appropriate boundary conditions. The dynamic analysis of non-uniform continuous structures is of primary interest, as most traditional methods take the help of discrete models to analyze them. Well established discrete model methods lead to an algebraic eigenvalue problem, the characteristic equation associated with which is a polynomial. The spectral characteristics of a continuous system nevertheless are represented by transcendental functions and cannot be approximated by polynomials efficiently. Hence finite dimensional discrete models are not capable of predicting the response of …


On The Stress Analysis Of Bimetallic Packing Rings, Eric Richard Lewis Jan 2007

On The Stress Analysis Of Bimetallic Packing Rings, Eric Richard Lewis

LSU Master's Theses

The purpose of this research is to try and understand hypercompressor packing ring failures better with a view of ultimately reducing or even eliminating their occurrences. In order to gain further understanding of packing ring failures, we seek to obtain an appreciation of the stresses they experience during operation. First we consider a conventional simulation of an axisymmetric packing ring and cup subjected to the typical pressure loading conditions experienced by these components when installed in a hypercompressor cylinder. The key locations of interest are along the bimaterial interface, and in particular at the ends of the interface. These ends …


Predictive Data Compression Using Adaptive Arithmetic Coding, Claudio Jose Iombo Jan 2007

Predictive Data Compression Using Adaptive Arithmetic Coding, Claudio Jose Iombo

LSU Master's Theses

The commonly used data compression techniques do not necessarily provide maximal compression and neither do they define the most efficient framework for transmission of data. In this thesis we investigate variants of the standard compression algorithms that use the strategy of partitioning of the data to be compressed. Doing so not only increases the compression ratio in many instances, it also reduces the maximum data block size for transmission. The partitioning of the data is made using a Markov model to predict if doing so would result in increased compression ratio. Experiments have been performed on text files comparing the …


Sigma-Delta Modulation Based Distributed Detection In Wireless Sensor Networks, Dimeng Wang Jan 2007

Sigma-Delta Modulation Based Distributed Detection In Wireless Sensor Networks, Dimeng Wang

LSU Master's Theses

We present a new scheme of distributed detection in sensor networks using Sigma-Delta modulation. In the existing works local sensor nodes either quantize the observation or directly scale the analog observation and then transmit the processed information independently over wireless channels to a fusion center. In this thesis we exploit the advantages of integrating modulation as a local processor into sensor design and propose a novel mixing topology of parallel and serial configurations for distributed detection system, enabling each sensor to transmit binary information to the fusion center, while preserving the analog information through collaborative processing. We develop suboptimal fusion …


Pre-Treatment Of Dynamically Varying Waste Gas Concentrations Using Activated Carbon Prior To Biofiltration: Effect Of Cycle Length On Degree Of Load Equalization, Kodi L. Collins Jan 2007

Pre-Treatment Of Dynamically Varying Waste Gas Concentrations Using Activated Carbon Prior To Biofiltration: Effect Of Cycle Length On Degree Of Load Equalization, Kodi L. Collins

LSU Master's Theses

Dynamically varying waste gas concentrations pose challenges to the operation and design of air pollution control techniques such as biofilters. Although design approaches are becoming well established for biofilters treating gases containing VOC concentrations that are constant as a function of time, many industrial processes emit gas streams contaminated with volatile organic compounds at concentrations that fluctuate with time. Application of an effective load equalization technique could eliminate some challenges associated with fluctuating pollutant concentrations. Recent research has demonstrated that granular activated carbon (GAC) can serve as a passively controlled system to provide load-equalization as a pre-treatment prior to biofiltration. …


Oblivious Transfer For Secure Communication, Abhishek Parakh Jan 2007

Oblivious Transfer For Secure Communication, Abhishek Parakh

LSU Master's Theses

Over the past four decades, computational power and algorithmic strategies have advanced tremendously resulting in an enormous increase in the key sizes required for secure cryptosystems such as RSA. At the same time, the electronic devices have grown smaller and portable requiring algorithms running on them to be optimized in size and efficiency while providing security, at least, equivalent to that provided on a typical desktop computer. As a result, the industry is moving towards newer cryptosystems such as ECC and NTRU that are well suited for resource constrained environments. While, ECC claims to provide security equivalent to that of …


Characterization Of Polyethylene Glycol Hydrogels For Biomedical Applications, Anushree Datta Jan 2007

Characterization Of Polyethylene Glycol Hydrogels For Biomedical Applications, Anushree Datta

LSU Master's Theses

Polyethylene glycol is one of the most widely used synthetic materials for biomedical applications. Its biocompatibility, flexibility, and 'stealth' properties make it ideal for use in drug delivery applications. The main objective of this paper is to characterize the structural and mass transfer properties of polyethylene glycol hydrogels for applications in drug delivery and biological immobilization. Swelling behavior of the gels was studied to determine the mesh size, and other significant structural parameters of the gel. For accurate design of drug delivery device, along with network design, mathematical modeling of release profiles was performed. The study of PEG hydrogels was …


Quasi Group Based Crypto-System, Maruti Venkat Kartik Satti Jan 2007

Quasi Group Based Crypto-System, Maruti Venkat Kartik Satti

LSU Master's Theses

For electronic commerce and other applications it is required to encrypt data that is transmitted over an unsecured channel. The data is encrypted/randomized using a key. Algorithms such as DES and ECC randomize the data such that un-authorized user cannot decrypt it .This thesis presents a practical implementation of a quasi group based multilevel, indexed scrambling transformation for use in signal encryption. Results of experiments with text and speech scrambling are presented. It is shown that the quasi group transformation maximizes the entropy at the output, which is desirable for a good system. This system provides extremely large group of …


Characterization And Analysis Of Hybrid Electronic Materials For Molecular Based Devices, Sathish Thiruvengadam Jan 2007

Characterization And Analysis Of Hybrid Electronic Materials For Molecular Based Devices, Sathish Thiruvengadam

LSU Master's Theses

The goal of this work is to characterize and to analyze hybrid electronic materials (HEMs) using fluorescence (FL) spectroscopy and conductive probe-atomic force microscopy (CP-AFM) in order to investigate the electrical and optical properties of these materials. Currently, research efforts to characterize novel organic materials for the determination of molecular level transport properties are of great interest.[6] One of the most interesting organic materials is the porphyrin molecule, which exhibits behavior useful for memory applications.[4] Colloidal CdS quantum dots (Q-CdS) capped with dioctyl sulfosuccinate (AOT) and thiol functionalized porphyrin molecules are explored for their potential application to next-generation hybrid electronic …


Saltwater Intrusion Simulation In Heterogeneous Aquifer Using Lattice Boltzmann Method, Borja Servan Camas Jan 2007

Saltwater Intrusion Simulation In Heterogeneous Aquifer Using Lattice Boltzmann Method, Borja Servan Camas

LSU Master's Theses

This study develops a saltwater intrusion simulation model using a lattice Boltzmann method (LBM) in a two-dimensional coastal confined aquifer. The saltwater intrusion is described by density-dependent groundwater flow and mass transport equations, where a freshwater-saltwater mixing zone is considered. The problem is formulated in terms of hydraulic head instead of pressure, which is recommended in those cases where static pressures dominate to reduce computational cost. The aquifer heterogeneity is explicitly a function of the speed of sound, relaxation parameter and time steps in the LBM. This study explores the equivalent squared sound speed to deal with the spatial-temporal heterogeneity …


Manufacturing, Testing And Modeling Of Advanced Filament Wound Grid Stiffened Composite Cylinders, Ravi Chaitanya Velamarthy Jan 2007

Manufacturing, Testing And Modeling Of Advanced Filament Wound Grid Stiffened Composite Cylinders, Ravi Chaitanya Velamarthy

LSU Master's Theses

Advanced Grid Stiffened (AGS) structures are a kind of FRP composites that are being extensively used in many engineering fields because of their inherent advantages. Hence it is of utmost importance to understand the basic mechanism of these structures in order to develop better models and to find ways to improve their efficiency. This thesis discusses the manufacturing technology used viz. the filament winding technique to fabricate grid stiffened composite cylinders. A step by step procedure of the fabrication process of grid cylinders is explained. The confinement effectiveness of the AGS cylinders is evaluated by filling them with concrete and …


Evaluation Of Consolidation Parameters Of Cohesive Soils Using Pcpt Method, Rohit Raj Pant Jan 2007

Evaluation Of Consolidation Parameters Of Cohesive Soils Using Pcpt Method, Rohit Raj Pant

LSU Master's Theses

The piezocone penetration test (PCPT) has emerged as most widely used in situ method for obtaining soil profile as well as physical properties. The PCPT method provides three independent and nearby continuous measurements with the depth; they are: tip stress (qc), sleeve friction (fs) and pore pressure (u1, u2, or u3). These measurements have been successfully used to correlate various soil properties such as undrained shear strength, unit weight and consolidation parameters. This study presents the evaluation of the PCPT interpretation methods for their capability to reasonably estimate the consolidation parameters namely constrained modulus, overconsolidation ratio and vertical coefficient of …


Computer-Aided Weld Inspection By Fuzzy Modeling With Selected Features, Sean Najm Ghazavi Jan 2007

Computer-Aided Weld Inspection By Fuzzy Modeling With Selected Features, Sean Najm Ghazavi

LSU Master's Theses

This thesis develops a computer-aided weld inspection methodology based on fuzzy modeling with selected features. The proposed methodology employs several filter feature selection methods for selecting input variables and then builds fuzzy models with the selected features. Our fuzzy modeling method is based on a fuzzy c-means (FCM) variant for the generation of fuzzy terms sets. The implemented FCM variant differs from the original FCM method in two aspects: (1) the two end terms take the maximum and minimum domain values as their centers, and (2) all fuzzy terms are forced to be convex. The optimal number of terms and …


Production Data Analysis Of Shale Gas Reservoirs, Adam Michael Lewis Jan 2007

Production Data Analysis Of Shale Gas Reservoirs, Adam Michael Lewis

LSU Master's Theses

Hydrocarbon resources from unconventional shale gas reservoirs are becoming very important in the United States in recent years. Understanding the effects of adsorption on production data analysis will increase the effectiveness of reservoir management in these challenging environments. The use of an adjusted system compressibility proposed by Bumb and McKee (1988) is critical in this process. It allows for dimensional and dimensionless type curves to be corrected at a reasonably fundamental level, and it breaks the effects of adsorption into something that is relatively simple to understand. This coupled with a new form of material balance time that was originally …


Biodegradation And Characterization Of A Bio-Based Polyester, Benjamin Edward Stevens Jan 2007

Biodegradation And Characterization Of A Bio-Based Polyester, Benjamin Edward Stevens

LSU Master's Theses

Anaerobic biodegradation in sewage sludge and aerobic biodegradation in compost of polyhydroxybutyrate (PHB) were investigated to determine degradation kinetics and identify changes in polymer properties. To determine the impact of a natural plasticizer on biodegradation, tributyl citrate (TBC) was blended with some test specimens. For comparison to another bioplastic, polylactic acid (PLA) was biodegraded in the anaerobic study. Evolved gaseous carbon was measured to assess biodegradability according to ASTM standards D5210 and D5338. Mass loss experiments were performed to facilitate determination of degradation kinetics. Melt-pressed plates of the bioplastic with five different initial mass-to-surface-area ratios (plate thicknesses of 0.24, 0.5, …


Studies On The Heat/Mass Transfer Characteristics And Fluid Structure In A Square Internal Cooling Channel With Dimpled Surfaces, Fuguo Zhou Jan 2007

Studies On The Heat/Mass Transfer Characteristics And Fluid Structure In A Square Internal Cooling Channel With Dimpled Surfaces, Fuguo Zhou

LSU Master's Theses

Experimental and numerical studies of heat/mass transfer on the dimpled surfaces in square channels are performed. The naphthalene sublimation method is employed in the experimental study. First, in a two-passage rotating channel, circle dimple matrices are cast on the leading and trailing walls in both the inlet and outlet of the serpentine channel. The experiments are carried out with Reynolds number of 7,000 and 21,000, and with Rotation number of 0 and 0.2. The dimpled walls lead to heat/mass transfer enhancements over smooth surfaces both in the stationary case and in the rotating case. In the stationary case, the dimple …


Optimization For Software Release And Crash, Tanvir Khan Jan 2007

Optimization For Software Release And Crash, Tanvir Khan

LSU Master's Theses

Software testing is a process to detect faults in the completeness and quality of developed computer software. Testing is a key process in assuring quality by identifying defects in software, and possibly fixing them, before it is delivered to end-users. A major decision to make during this software testing is, to determine whether to continue testing and eventually releasing the software, or when to stop the test and ‘crash’ it. Such a decision needs to be made to optimally balance the tradeoff between the cost of development and the reliability of the software. In this paper, a new optimal strategy …


Passive Alignment Of Micro-Fluidic Chips Using The Principle Of Elastic Averaging, Sitanshu Gurung Jan 2007

Passive Alignment Of Micro-Fluidic Chips Using The Principle Of Elastic Averaging, Sitanshu Gurung

LSU Master's Theses

This thesis presents a novel design for a passive alignment feature for vertically stacking chips in a micro fluidic device. Each chip is the size of a standard microscopic slide (75mm—25mm) and is a highly specialized functional unit designed and fabricated to process fluidic samples. The fluidic samples in the device flows from one chip to another using inter connecting holes 500μm-100μm in diameter. Hence an alignment of better than 100μm between chips is necessary to allow for the interconnecting holes to overlap so as to provide with a path for the fluid to flow. The feature to be used …


Data Compression With Application To Geo-Location, William Perkins Jan 2007

Data Compression With Application To Geo-Location, William Perkins

LSU Master's Theses

A common way to locate an emitter within a wireless sensor network requires the estimation of time-difference-of-arrival (TDOA) parameters using data collected by a set of spatially separated sensors. Compressing the data that is shared among the sensors can provide tremendous savings in terms of the energy and transmission latency. Traditional MSE and perceptual based data compression schemes fail to accurately capture the effects of compression on the TDOA estimation task; therefore, it is necessary to investigate compression algorithms suitable for TDOA parameter estimation. This thesis explores the effects of data compression on TDOA parameter estimation accuracy. The first part …


Measuring Skeletal Kinematics With Accelerometers On The Skin Surface, Kevin Curtis Ayer Jan 2007

Measuring Skeletal Kinematics With Accelerometers On The Skin Surface, Kevin Curtis Ayer

LSU Master's Theses

The most common motion analysis method uses cameras to track the position of markers on bodily surfaces over time. Although each species has a common skeletal frame to reference recorded motions, the soft tissue covering each is not rigid. Markers, therefore, experience motion relative to the bone and do not accurately portray underlying bone activity. This limits clinical use of motion studies and the understanding of joint motion. Use of MEMS accelerometers for removing soft tissue artifact, motion relative to the bone, from surface measurements and determining the position of the underlying bone was investigated. An animal limb was modeled …


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 …


Jet Impingement Cooling Configurations For Gas Turbine Combustion, Eric Ian Esposito Jan 2006

Jet Impingement Cooling Configurations For Gas Turbine Combustion, Eric Ian Esposito

LSU Master's Theses

Impinging jets are commonly used to enhance heat transfer in modern gas turbine engines. Impinging jets used in turbine blade cooling typically operate at lower Reynolds numbers in the range of 10,000 to 20,000. In combustor liner cooling, the Reynolds numbers of the jets can be as high as 60,000. The present study is aimed at experimentally testing two different styles of jet impingement geometries to be used in backside combustor cooling. The higher jet Reynolds numbers lead to increased overall heat transfer characteristics, but also an increase in crossflow caused from spent air. The crossflow air has the effect …


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 …


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 …


Evaluation Of Media Influence And Practical Applications For The Use Of Static Low Density Media Filters In Domestic Wastewater Treatment, Steven Marty Bellelo Jan 2006

Evaluation Of Media Influence And Practical Applications For The Use Of Static Low Density Media Filters In Domestic Wastewater Treatment, Steven Marty Bellelo

LSU Master's Theses

Static Low Density Media filters have been used over the past two decades for nitrification and solids removal in high-density recirculating aquaculture systems. The SLDM filters are submerged biofilters which contain a plastic media with a density less than that of water. The media beds remain packed, or static, during operation except for periodic expansion of the bead bed during a backwash. More recently SLDM filters have been evaluated for secondary clarification of domestic wastewater where concurrent biological treatment and particulate removal occur within one unit. Recirculation is accomplished using airlifts which provide external aeration coupled with multiple pass removal …


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 …


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 …


Frictional Interaction Properties Between Geomaterials And Geosynthetics, Julian Javier Coronel Jan 2006

Frictional Interaction Properties Between Geomaterials And Geosynthetics, Julian Javier Coronel

LSU Master's Theses

Soil reinforcement interaction is a primary issue for designing reinforced soil structures. The soil to geosynthetic interaction parameters are influenced by a) Interaction mechanism between geomaterials and geosynthetics (pull-out or direct shear), b) Physical and mechanical properties of geomaterials (density, grain shape and size, grain size distribution, water content, and plasticity of clayey soils), and c) Mechanical properties (tensile peak strength), shape and geometry of geosynthetics. The soil to geogrid interface friction parameters (interface friction angle "δ" and adhesion "ca") for different plasticity indexes, moisture contents, and dry densities were investigated. For this purposes, a large scale direct …


Partial Continuity In Prestressed Concrete Girder Bridges With Jointless Decks, Ram Naren Mothe Jan 2006

Partial Continuity In Prestressed Concrete Girder Bridges With Jointless Decks, Ram Naren Mothe

LSU Master's Theses

Jointless multi-simple span deck-girder (composite concrete deck with steel or prestressed concrete girders) bridge construction has been accepted as an alternative to jointed construction. Bridge deck joints add to the construction and maintenance costs of the bridge. Bridge support bearing pads deterioration is a common problem in bridges with jointed bridge decks. One of the methods used for building a jointless bridge is to provide a link slab that connects the decks of the adjacent spans. This study mainly focuses on the behavior of the link slab and its effect on the behavior of the bridge system as a whole. …