Digital Commons Network^™

Investigations Of Wave-Induced Turbulent Structures In Vegetated Flows, Agnimitro Chakrabarti

LSU Master's Theses

The role of coastal vegetation in mitigating shoreline erosion by damping of incoming waves and the resultant effect on sediment transport is a critical area of coastal management research. However our understanding of the underlying hydrodynamic processes is limited. Laboratory flume experiments were conducted where a naturally grown emergent vegetation channel and a vegetation-less sand channel were exposed to regular waves. Wave height data was collected using wave gauges located at various points along the channel in the direction of oncoming waves. Acoustic Doppler Velocimeters (ADVs) placed at various depths in the water column measured wave orbital velocity signatures. This …

A Methodology Towards Comprehensive Evaluation Of Shape Memory Alloy Actuators For Prosthetic Finger Design, Kevin O'Toole

Doctoral

Presently, DC motors are the actuator of choice within intelligent upper limb prostheses. However, the weight and dimensions associated with suitable DC motors are not always compatible with the geometric restrictions of a prosthetic hand; reducing available degrees of freedom and ultimately rendering the prosthesis uncomfortable for the end-user. As a result, the search is on-going to find a more appropriate actuation solution that is lightweight, noiseless, strong and cheap. Shape memory alloy (SMA) actuators offer the potential to meet these requirements. To date, no viable upper limb prosthesis using SMA actuators has been developed. The primary reasons lie in …

Anti-Microbial Self-Assembling "Click" Monolayers Utilizing Silver Nanoparticles For Indwelling Medical Devices, Emily Ann Hodges

LSU Master's Theses

The objective of this study was to synthesize and characterize antimicrobial, silver nanoparticles based self-assembling monolayer coatings, for use on chronic indwelling medical devices. The coatings are comprised of novel biomass mediated silver nano particles (SNP) that are biocompatible, highly concentrated, highly pure, cost-effective, polydispersed and compatible for use with existing chronic indwelling medical devices. The HPC SNPs were functionalized with an azide functional group and covalently bound to titanium substrates via ¨Dclick¡¬ chemistry.

Emerging M&S Application In Risk Management, C. Ariel Pinto, Andreas Tolk, Michael Mcshane

Engineering Management & Systems Engineering Faculty Publications

There has been compelling signs of the great potential of building further synergy with academics, researchers, and industry practitioners from the areas of Modeling and Simulation (M&S) managing risk events. This paper provides an introduction to risk management and how M&S has permeated the risk management process. The trend has been to harness the advantages of M&S tools and techniques in terms of efficiency and effectiveness in managing risks. However, the more important contribution of M&S may be in how it provides a way for specialists in various disciplines or industries interact to manage risks that require multi-disciplinary approach. This …

Evaluating Algal Growth At Different Temperatures, Keelin Owen Cassidy

Theses and Dissertations--Biosystems and Agricultural Engineering

In recent years, there has been a concern for the amount of carbon dioxide released into the atmosphere and how it will be captured. One way to capture carbon dioxide is with algae. In this study, algae's growth was measured at different temperatures. The first part of the study was to grow Scenedesmus and Chlorella with M8 or urea growth media at a temperature of 25, 30 or 35ºC. It was found that 30ºC had the best growth rates for both algae. The second part studied Scenedesmus growth with urea, more in-depth, and found the optimum growth temperature to be …

Synthesis And Characterization Of Carbon Magnetic Nanoparticles, Sunilsingh Gusain

Material Science and Engineering Theses - Archive

Carbon incorporated iron nanoparticles (Fe-CNPs) were successfully synthesized using ultrasonic cavitation in Benzene. This novel method of carbon nanoparticle (CNP) synthesis is a very cost-effective and versatile as one can easily tune the microstructure and magnetic properties by varying few parameters, for e.g. voltage. The Fe-CNP complexes are produced due to the electric plasma discharge generated between the electrodes in an ultrasonic cavitation field of liquid benzene. The constituent of the CNPs can be easily modified by different choice of electrode materials- iron and graphite. The resultant Fe-CNPs were characterized by high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy to …

The Design And Modification Of A Sputter System For Dc Reactive Sputtering Of Alumina And Zirconia Thin Films, Diane Van Ho

LSU Master's Theses

Yttria-stabilized zirconia (7% YSZ) is the most used material for thermal barrier coatings (TBCs) to reduce the conductive heat transfer on turbine blades, but it is not resistant to infrared radiation. In order to reduce radiation heat transfer, alternating materials, such as alumina and zirconia, can be used to fabricate multi-layer coatings in which each layer is optimized to reflect a targeted range of wavelength. This research aims to fabricate these multi-layer coatings by reactive magnetron sputtering. Reactive magnetron sputtering is the sputtering of an elemental target in the presence of a reactive gas that will react with the target …

Screening Of Tar Cracking Catalysts For Syngas Produced By Biomass Gasification, Bijeet Mukherjee

LSU Master's Theses

The gasification of biomass produces tars and particulates. These tars and particulates create problems in the gasification systems. Tars condense on surfaces at lower temperatures, such as exit pipes and on particulate filters, leading to blockages and clogged filters. Tars also have varied impacts on other downstream processes. Due to these reasons, syngas containing significant concentrations of tars cannot be used in internal combustion engines. Thus the processes through which tars can be removed have been subject to considerable research. The objective of this research was to identify the best catalyst for for down-draft gasifiers, including the LSU AgCenter down-draft …

Development Of A Total Nutrient Treatment System For Alligator And Dairy Parlor Wastewater Using Hydrated Lime And Organic Bacterial Growth Media, Troy Francis Davis

LSU Master's Theses

Over application of phosphorus and the loss of ammonia-nitrogen to runoff and volatilization have resulted in the buildup of phosphorus in agricultural top soils around the world, and especially in the United States. Over the past few decades, raising livestock has trended towards the development of the Confined Animal Feeding Operations (CAFO’s) which produce large volumes of wastes that need to be treated before being land applied. Nutrient treatment systems have typically focused on one nutrient singularly: either nitrogen or phosphorus. In order to develop a total nutrient system a phosphorus and nitrogen system had to be developed and evaluated …

Test 1999a: John Deere 8335rt My12, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Column: The Physics Of Digital Information, Fred Cohen

Journal of Digital Forensics, Security and Law

No abstract provided.

Coupled Photonic Crystal Micro-Cavities With Ultra-Low Threshold Power For Stiumulated Raman Scattering, Qiang Liu, Zhengbiao Ouyang, Sacharia Albin

Electrical & Computer Engineering Faculty Publications

We propose coupled cavities to realize a strong enhancement of the Raman scattering. Five sub cavities are embedded in the photonic crystals. Simulations through finite-difference time-domain (FDTD) method demonstrate that one cavity, which is used to propagate the pump beam at the optical-communication wavelength, has a Q factor as high as 1.254 × 10⁸ and modal volume as small as 0.03μm³ (0.3192(λ/n)³). These parameters result in ultra-small threshold lasing power ~17.7nW and 2.58nW for Stokes and anti-Stokes respectively. The cavities are designed to support the required Stokes and anti-Stokes modal spacing in silicon. The proposed structure …

Developing A Tool To Characterize The Ultradian Rhythm In Diploid Saccharomyces Cervisiae Using The Reporter Gene Green Fluorescent Protein, Imran Chiragh

LSU Master's Theses

Biological rhythms control many temporal behaviors of organism, such as the sleep cycle, hearts rhythms, seasonal animal migrations etc. Understanding these rhythms would provide insight into the temporal process of living organisms. Saccharomyces cerevisiae, a budding yeast, is an ideal model organism to study biological rhythms in eukaryotic cells because of its sequenced genome and discerned processes. By characterizing the biological rhythm in budding yeast, insight can be gained into more complex organisms. Previous studies have exhibited oscillatory behavior of oxygen consumption and determined that deletion of the GTS1 gene dissipates this rhythm. However, to further understand the specific behavior …

Bcc Skin Cancer Diagnosis Based On Texture Analysis Techniques, Shao-Hui Chuang, Xiaoyan Sun, Wen-Yu Chang, Gwo-Shing Chen, Adam Huang, Jiang Li, Frederic D. Mckenzie

Electrical & Computer Engineering Faculty Publications

In this paper, we present a texture analysis based method for diagnosing the Basal Cell Carcinoma (BCC) skin cancer using optical images taken from the suspicious skin regions. We first extracted the Run Length Matrix and Haralick texture features from the images and used a feature selection algorithm to identify the most effective feature set for the diagnosis. We then utilized a Multi-Layer Perceptron (MLP) classifier to classify the images to BCC or normal cases. Experiments showed that detecting BCC cancer based on optical images is feasible. The best sensitivity and specificity we achieved on our data set were 94% …

2d Face Database Diversification Based On 3d Face Modeling, Qun Wang, Jiang Li, Vijayan K. Asari, Mohammad A. Karim, Manuel Filipe Costa (Ed.)

Electrical & Computer Engineering Faculty Publications

Pose and illumination are identified as major problems in 2D face recognition (FR). It has been theoretically proven that the more diversified instances in the training phase, the more accurate and adaptable the FR system appears to be. Based on this common awareness, researchers have developed a large number of photographic face databases to meet the demand for data training purposes. In this paper, we propose a novel scheme for 2D face database diversification based on 3D face modeling and computer graphics techniques, which supplies augmented variances of pose and illumination. Based on the existing samples from identical individuals of …

Ductile Mode Material Removal Of Ceramics And Semiconductors, Deepak Ravindra

Dissertations

Ceramics and semiconductors are hard, strong, inert and lightweight. They also have good optical properties, wide energy bandgap and high maximum current density. This combination of properties makes them ideal candidates for tribological, semiconductor, MEMS and optoelectronic applications respectively. Manufacturing these materials without causing surface and subsurface damage is extremely challenging due to their high hardness, brittle characteristics and poor machinability. However, ductile regime machining of these materials is possible due to the high-pressure phase transformation occurring in the material caused by the high compressive stresses induced by the single point diamond tool tip. In this study, to further augment …

Small Footprint High Flow Rate Microdevice For Rare Target Cell Capture, Taehyun Park

LSU Doctoral Dissertations

A novel high flow rate cell capture design was introduced to overcome the limitations of the current technologies or methods for rare target cell capture. Even though the rare target cell capture using BioMEMS technology has great potential for cancer diagnosis, previous rare cell capture research could not overcome the limitations of low flow rate or low recovery rate. Rare cell research requires precise sample preparation for accurate results. A new method of preparation for a single or a precise number of target cell was introduced. Current sample preparation methods which are not suitable for rare cell research, such as …

Surface Functionalization Of Crystalline Silicon Substrates, Sri Sai Vegunta

LSU Doctoral Dissertations

In this work, various chemical and electrochemical methods were demonstrated to attach application-specific organic monolayers to crystalline silicon substrates. In one study, alkyl monolayers were anodically electrografted or thermally grafted onto planar (100) silicon substrates using Grignard precursors. The results show electrografted methyl monolayers provide a stable Si-C termination, resisting oxidation on (100) surfaces for approximately 55 days in air. The alkyl termination could provide a potential alternative to defective native oxides and kinetically unstable hydride surfaces. A mechanism involving two electron transfers per grafting event was established for both the thermal and electrochemical routes. In another study, unsaturated organic …

High Speed Continuous Thermal Curing Microfabrication System, Franklin Dibartolomeo

University of Kentucky Master's Theses

Rapid creation of devices with microscale features is a vital step in the commercialization of a wide variety of technologies, such as microfluidics, fuel cells and self-healing materials. The current standard for creating many of these microstructured devices utilizes the inexpensive, flexible material poly-dimethylsiloxane (PDMS) to replicate microstructured molds. This process is inexpensive and fast for small batches of devices, but lacks scalability and the ability to produce large surface-area materials. The novel fabrication process presented in this paper uses a cylindrical mold with microscale surface patterns to cure liquid PDMS prepolymer into continuous microstructured films. Results show that this …

Characterization Of Novel Akermanite:Poly-E-Caprolactone Scaffolds For Bone Tissue Engineering Aapplications Combined With Human Adipose-Derived Stem Cells, Andre S. Zanetti

LSU Doctoral Dissertations

The development of porous materials useful as scaffolds for the sustained three-dimensional (3D) growth of human adipose-derived stem cells (hASC) is of particular interest to facilitate healing after musculoskeletal injuries. In this study, a composite porous material obtained by blending akermanite with poly-e-caprolactone (PCL) is proposed as novel alternative to bone tissue regeneration. The objectives of this study are (1) to characterize the akermanite:PCL scaffold properties; (2) to investigate the in vitro osteogenic potential of hASC loaded to optimal akermanite:PCL scaffolds; (3) to assess the metabolic activity and osteogenesis of hASC loaded to optimal akermanite:PCL scaffolds post-thawing using optimal cryopreservation …

Implementation Of A Wireless Sensor Network With Ez430-Rf2500 Development Tools And Msp430fg4618/F2013 Experimenter Boards From Texas Instruments, Lu De Yang

LSU Master's Theses

Wireless sensor networks have found a great deal of applications in diverse areas. Recent interest has been focused on low-power feature of the sensor nodes because the power consumption is always an issue for wireless sensor nodes which are supplied from the batteries. The eZ430RF2500 Development Tool and MSP430FG4618/F2013 Experimenter Board from Texas Instruments have integrated MSP430 family of ultralow-power microcontrollers and CC2500 low-power wireless RF transceivers which are suitable for low-power, low-cost wireless applications. In this thesis, the features of these TI devices are explored and a wireless sensor network is implemented with these devices. To implement the routing …

Molecular Dynamics Simulation Studies Of Surface-Stress Effects In Metallic Nanostructures, Jijun Lao

LSU Doctoral Dissertations

Using molecular dynamics (MD) simulations we investigate the surface-stress-induced structural transformations and pseudoelastic behavior in palladium (Pd) crystalline nanowires. For a <100> initial crystal orientation our studies indicate that the surface stress can cause Pd nanowires to spontaneously undergo structural changes with characteristics that are determined by the wire cross-sectional area. Specifically, when the cross-sectional area is below 2.18nm x 2.18nm the wire changes spontaneously its crystal structure from the initial fcc structure to a body-centered-tetragonal (bct) structure. In wires of larger cross-sectional area (i.e., 2.57nm x 2.57nm) the structural transformation is achieved via a spontaneous lattice reorientation leading to an …

Computer Simulation Of A Hollow-Fiber Bioreactor: Heparan Regulated Growth Factors-Receptors Binding And Dissociation Analysis, Changjiang Zhang

University of Kentucky Doctoral Dissertations

This thesis demonstrates the use of numerical simulation in predicting the behavior of proteins in a flow environment.

A novel convection-diffusion-reaction computational model is first introduced to simulate fibroblast growth factor (FGF-2) binding to its receptor (FGFR) on cell surfaces and regulated by heparan sulfate proteoglycan (HSPG) under flow in a bioreactor. The model includes three parts: (1) the flow of medium using incompressible Navier-Stokes equations; (2) the mass transport of FGF-2 using convection-diffusion equations; and (3) the cell surface binding using chemical kinetics. The model consists of a set of coupled nonlinear partial differential equations (PDEs) for flow and …

Droplet Motion On Miniaturized Ratchets, Jeong Tae Ok

LSU Doctoral Dissertations

The main objective of this study is to evaluate the feasibility of using miniaturized asymmetric structures to move liquid droplets and understand the driving mechanism. We developed the fabrication process for large area topological ratchets with the period ranging from millimeter down to sub-micrometer using micromachining techniques. Non-wetting superhydrophobic surfaces were successfully fabricated using soft UV or thermal nanoimprint lithography, reactive ion etching by oxygen plasma, and chemical surface modification by fluorinated silane vapor deposition. An accurate and reproducible experimental setup equipped with high speed camera and automatic injection system was established. Image processing tools allowed us to obtain various …

Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …

Foldable Substrates For Micro-Ultrasonic Transducers, Karthik Balasubramanian

LSU Master's Theses

Ultrasound has broad range of applications from underwater examination, nondestructive testing of materials and medical diagnosis and treatment. The ultrasonic transducer plays an vital role in determining the resolution, sensitivity, as well as other diagnostic capabilities of an ultrasonic imaging system. Current piezoelectric transducer which dominates the medical field has limited applications compared to the capacitive ultrasonic transducer. The capacitive transducer is easy to fabricate compared to the piezoelectric transducer. In this work, the fabrication of a foldable substrate for a capacitive ultrasonic transducer has been discussed. The foldable substrate was fabricated using an ultrathin silicon wafer which is 50 …

Control Characteristics Of An All-Digital Proportional-Integral-Derivative (Pid) Compensator, David Michael Feinauer

Theses and Dissertations--Electrical and Computer Engineering

The digitization of classical control systems presents a number of challenges and opportunities with respect to the miniaturization, distribution, reliability verification and obsolescence of both the controller and the underlying system under control. A method for the design of proportional-integral-derivative (PID) compensators realized in the form of all-digital components is presented. All-digital refers to a system implementation that is realizable with a wide range of digital logic components including discrete digital logic elements and programmable logic devices (PLDs) such as field-programmable gate arrays. The proportional, integral and derivative components of the classical PID control law were re-envisioned in terms of …

Design Of Laser Multi-Beam Generator For Plant Discrimination, Sreten Askraba, Arie Paap, Kamal Alameh, John Rowe

Research outputs 2011

Optimisation of the optical signal from the laser multi-spot beam generator employed in a photonic based real-time plant discrimination sensor for use in selective herbicide spraying systems is presented. The plant detection sensor uses a three-wavelength laser diode module that sequentially emits identically-polarized laser light beams through a common aperture, along one optical path. Each laser beam enters a multi-spot beam generator which produces 15 parallel laser beams over a 240mm span. The intensity of the reflected light from each spot is detected by a high-speed line scan image sensor. Plant discrimination is based on calculating the slope of the …

Estimation Of The Centre Of Mass From Motion Capture And Force Plate Recordings: A Study On The Elderly, Sebastien Cotton, Michele Vanoncini, Philippe Fraisse, Nacim Ramdani, Emel Demircan, Andrew P. Murray, Thierry Keller

Mechanical and Aerospace Engineering Faculty Publications

The estimation of the centre of mass position in humans is usually based on biomechanical models developed from anthropometric tables. This method can potentially introduce errors in studies involving elderly people, since the ageing process is typically associated with a modification of the distribution of the body mass. In this paper, an alternative technique is proposed, and evaluated with an experimental study on 9 elderly volunteers. The technique is based on a virtual chain, identified from experimental data and locating the subject's centre of mass. Its configuration defines the location of the centre of mass, and is a function of …

Computational Investigation Of Particle Settling Effects On Inhaled Submicron Bioaerosol Deposition In The Human Lung, Mohammed Ali, Essam A. Ibrahim

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 1-5