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Ultra-Violet Lithography Of Thick Photoresist For The Applications In Biomems And Micro Optics, Ren Yang

LSU Doctoral Dissertations

UV lithography of thick photoresist is widely used in microelectromechanical systems (MEMS) and micro-optoelectromechanical systems (MOEMS). SU-8 is a typical negative tone thick photoresist for micro systems, and can be used for both structural material and pattern transfer. This dissertation presents an effort to comprehensively study these important subjects. The first part, and the most fundamental part of this dissertation concentrated on the numerical analysis and experimental study of the wavelength dependent absorbance of SU-8 and the diffraction effects on the sidewall profiles of the microstructures made using UV lithography of SU-8. This study has laid the foundation for all …

Distribution Dynamics Of Complex Systems, Young-Pyo Jeon

LSU Doctoral Dissertations

A complex system is defined as a system with many interdependent parts having emergent self-organization; analyzing and designing such complex systems is a new challenge. A common observable structure of many complex systems is the network, which is connections among nodes, and thus inherently difficult to describe. The goal of this research is to introduce an effective methodology to describe complex systems, and thus we will construct a population balance (distribution kinetics) model based on the association-dissociation process to describe the evolution of complex systems. Networks are commonly observed structures in complex systems with interdependent parts that self-organize. How networks …

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 …

Evaluation Of An Amperometric Biosensor For The Detection Of Escherichia Coli O157:H7, Danyelle Denise Small

LSU Master's Theses

Escherichia coli O157:H7 contamination is a major hazard in the water supply, causing outbreaks of disease. Conventional methods of E. coli O157:H7 detection usually takes 1-2 days and require hands-on preparation. There is a need to develop a rapid, inexpensive means of detecting the organism. The amperometric biosensor technology has achieved success in the area of metabolite detection. In this study, a bench scale amperometric biosensor was investigated to rapidly detect Escherichia coli O157:H7. The amperometric biosensor consisted of a power source, Clark electrode, autoranging picoammeter, and fabricated polyvinyl chloride (PVC) outer insert with nitrocellulose membrane and attached horseradish peroxidase …

Dynamics Of An Atmospheric Pressure Plasma Plume Generated By Submicrosecond Voltage Pulses, Xinpei Lu, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

Nonequilibrium plasmas driven by submicrosecond high voltage pulses have been proven to produce high-energy electrons, which in turn lead to enhanced ionization and excitations. Here, we describe a device capable of launching a cold plasma plume in the surrounding air. This device, "the plasma pencil," is driven by few hundred nanosecond wide pulses at repetition rates of a few kilohertz. Correlation between current-voltage characteristics and fast photography shows that the plasma plume is in fact a small bulletlike volume of plasma traveling at unusually high velocities. A model based on photoionization is used to explain the propagation kinetics of the …

Reproducing Published Results From In Silico Computer Models Of The Acute Inflammatory Response To Severe Sepsis, Wayne W. Wakeland, Joe Fusion, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

Recent studies describe computer simulation models of the acute or systemic inflammatory response (AIR or SIR) to severe sepsis, a condition that can lead to multiple organ failure and death. One study used an agent-based model, while the other used differential equations (DEs) to simulate a randomized clinical trial. Both studies obtained results similar to the actual results from a successful clinical drug trial of severe sepsis, suggesting that in silico (simulated) randomized clinical trials may be used to design more effective in vivo clinical trials.

Use Of Thermally Induced Higher Order Modes Of A Microcantilever For Mercury Vapor Detection, Gregory P. Nordin, Michael A. George, Ashwini R. Kadam

Faculty Publications

We demonstrate the use of thermally induced higher order modes of a microcantilever as an alternate detection technique by studying Au-Hg interactions. The first four thermally induced flexural modes - i.e., the fundamental and first three higher order modes - have been examined for two different Au coatings. In the first case, 50 nm thick Au is sputter deposited along the entire length of a rectangular Si microcantilever. In the second case the Au is confined to a 30 µm length at the tip of the Si microcantilever. In both cases the microcantilever spectral response and deflection has been studied …

Gis And 3d Analysis Applied To Sea Turtle Mortalities And Navigation Channel Dredging, Bradley A. Shellito, Keith B. Lockwood

Virginia Journal of Science

Between 2000 and 2003 there were an increased number of documented sea turtle mortalities related to hopper dredging in the channels of the Chesapeake Bay. A pilot study was undertaken to create a bathymetric surface and three-dimensional model of the Cape Henry Channel using Geographic Information Systems (GIS) as a visualization tool to examine sea turtle mortalities in relation to the dredging. In Fall 2003, the US Army Corps of Engineers dredged the Thimble Shoals Federal Navigation Channel, and a more refined model was developed using this data. This project examines the growing concerns over sea turtle mortality rates and …

Recombinant Human Bmp-7 Effectively Prevents Non-Union In Both Young And Old Rats, David J. Hak, Takeshi Makino, Takahiro Niikura, Scott J. Hazelwood, Shane Curtiss, A. Hari Reddi

Biomedical Engineering

The purpose of this study was to evaluate the influence of age on the effectiveness of rhBMP-7 treatment in a fracture with severe periosteal damage that is known to result in non-union formation. Closed stabilized femur fractures were produced in 3-month-old and 18-month-old rats. The fracture site was exposed and 2 mm of the periosteum cauterized circumferentially to impair normal fracture healing. The cauterized fracture site was immediately treated with either 100 mg rhBMP-7 (BMP-7 group), or with 25 xL of vehicle alone (control group). Fracture healing was evaluated with radiographs taken at 3 and 6 weeks. Animals were sacrificed …

Enzyme Engineering Of Aminotransferases For Improved Activity And Thermostability, Abraham Rogelio Mártin García

Dissertations, Master's Theses and Master's Reports - Open

The production by biosynthesis of optically active amino acids and amines satisfies the pharmaceutical industry in its demand for chiral building blocks for the synthesis of various pharmaceuticals. Among several enzymatic methods that allow the synthesis of optically active aminoacids and amines, the use of minotransferase is a promising one due to its broad substrate specificity and no requirement for external cofactor regeneration. The synthesis of chiral compounds by aminotransferases can be done either by asymmetric synthesis starting from keto acids or ketones, and by kinetic resolution starting from racemic aminoacids or amines.

The asymmetric synthesis of substituted (S)-aminotetralin, an …

Postharvest Treatment To Control Codling Moth In Fresh Apples Using Water Assisted Radio Frequency Heating, Shaojin Wang, Sohan Birla, J. D. Hansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Apples destined for export to Japan and South Korea are currently disinfested for codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), using methyl bromide fumigation. Restrictions and limitations imposed on the uses of methyl bromide have increased interest in developing alternative non-chemical quarantine treatments. It is imperative that the treatment is effective against codling moth yet maintains the quality of treated apples. The present study explored the application of radio frequency (RF) energy in conjunction with conventional hot water treatment to develop feasible heat treatments. Treatment parameters were selected based on minimum time–temperature conditions required for 100% mortality of fifth-instar codling …

Heat Transfer And Chemical Processes In Chemical Vapor Deposition Reactor For Synthesis Of Carbon Nanotubes, Wahed Rezk Wasel

University of Kentucky Doctoral Dissertations

A small-scale model of a CVD reactor was built. Axial and radial of major species concentrations and temperature profiles were obtained with a micro gas chromatograph and a fine thermocouple. Those temperature and species concentrations revealed detailed thermal and chemical structures of the CVD reactor.

The concentrations of argon plus hydrogen, methane, and C₂H_x (C₂H₂ + C₂H₄ + C₂H₆) resulting from xylene decomposition were measured along the CVD at different temperatures. Ferrocene was added to xylene to investigate the effect of a catalyst on composition profiles. The …

Reduction Of Automobile And Aircraft Collisions With Wildlife In Indiana, David J. Glista, J. Andrew Dewoody, Travis Lee Devault

JTRP Technical Reports

Conflicts between wildlife and human interests have increased in recent decades due to growing human populations and the resulting expansion of anthropogenic pressures into wildlife habitat. Our overall objectives were to evaluate the the potential impacts of wildlife on transportation in Indiana and vice-versa. The results presented in this final report summarize two aspects of our research: the impact of automotive traffic on wildlife (“road kill”; Part I), and the wildlife hazards present at general aviation airports around the state (“airstrike”; Part II). The road kill dataset indicated that at 13 survey routes traversing 180 linear km of road, 11,068 …

Pi And Pid Controller Tuning Rules: An Overview And Personal Perspective, Aidan O'Dwyer

Conference papers

The ability of PI and PID controllers to compensate many practical processes has led to their wide acceptance in industrial applications. The requirement to choose two or three controller parameters is most easily done using tuning rules. Starting with a general discussion of industrial practice, the paper provides a survey of additional tuning rules for continuous-time PI and PID control of time-delayed single-input, single-output (SISO) processes, to those explored in a recent book by the author.

Synthesising Life-Sciences And Control Engineering: An Outline Survey And A Practical Example, Aidan O'Dwyer

Conference papers

There is an increasing interest in life science related areas in the electrical and control engineering community [1]. One manifestation of this interest is the development of interdisciplinary programmes, such as the B.Sc. in Medical Physics and Bioengineering, offered by the Dublin Institute of Technology from September 2005. A significant amount of research work in control engineering has focused on aspects of human physiological system, for example blood glucose regulation [2], cardiovascular modelling and control [3], and limb control [4]. There is an increasing emphasis on interdisciplinary research; in recognition of this, the Institute of Electrical Engineers (IEE) has starting …

Density Estimation Using A Generalized Neuron, R. Kiran, Ganesh K. Venayagamoorthy, M. Palaniswami

Electrical and Computer Engineering Faculty Research & Creative Works

Neural networks have been shown to be useful tools for density estimation. However, the training of neural network structures is time consuming and requires fast processors for practical applications. A new method with a generalized neuron (GN) for density estimation is presented in this paper. The GN is trained with the particle swarm optimization algorithm which is known to have fast convergence than the standard backpropagation algorithm. Results are presented to show that the GN can estimate the density functions for distribution functions with different means and variances. This density estimation method can also be applied to the multi-sensor data …

Surface Modification Of Su-8 By Photografting Of Functional Polymers For Lab-On-A-Chip Applications, Zhan Gao, David Henthorn, Chang-Soo Kim

Chemical and Biochemical Engineering Faculty Research & Creative Works

Due to the high flexibility and versatility in the process development of microfluidic devices, an epoxybased, high-aspect ratio photoresist SU-8 is now attracting attention as the main structuring material of the fluidic channels. Manipulation of the surface properties of SU-8 channel wall is critical to attach functional films such as enzyme-immobilized layers or biocompatible layers. We describe a new in situ patterning method to form a hydrogel film on SU-8 by a photografted polymerization procedure. The hydrophobic surface of SU-8 is modified using a surface bound initiator HCPK (1-hydroxycyclohexyl phenyl ketone). A p-HEMA (poly-2-hydroxyethylmethacrylate) hydrogel film is grafted by photopolymerization …

Heuristics And Genetic Algorithms, Michael D. Mobley, Cihan H. Dagli, David Enke

Engineering Management and Systems Engineering Faculty Research & Creative Works

Genetic algorithms are design tools used in generating optimal solutions. While they can often be shown to outperform various heuristic methods and hybrid approaches, using a combination of evolutionary algorithms and heuristic approaches can generate an optimal solution more quickly than either of the two methods independently. Our purpose is to provide an overview of genetic algorithms, to discuss the types of problems that lend themselves to being solved by genetic algorithms, and to identify heuristics that have been shown to aid genetic algorithms in their quest for optimal solutions. While the sample problems discussed in this paper are generally …

Design Of Near-Optimal Waveforms For Chest And Abdominal Compression And Decompression In Cpr Using Computer-Simulated Evolution, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Objective: To discover design principles underlying the optimal waveforms for external chest and abdominal compression and decompression during cardiac arrest and CPR. Method: A 14-compartment mathematical model of the human cardiopulmonary system is used to test successive generations of randomly mutated external compression waveforms during cardiac arrest and resuscitation. Mutated waveforms that produced superior mean perfusion pressure became parents for the next generation. Selection was based upon either systemic perfusion pressure (SPP=thoracic aortic minus right atrial pressure) or upon coronary perfusion pressure (CPP=thoracic aortic pressure minus myocardial wall pressure). After simulations of 64,414 individual CPR episodes, 40 highly evolved waveforms …

A New Biomechanical Head Injury Criterion, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This paper presents a new analysis of the physics of closed head injury caused by intense acceleration of the head. At rest a 1 cm gap filled with cerebrospinal fluid (CSF) separates the human brain from the skull. During impact whole head acceleration induces artificial gravity within the skull. Because its density differs slightly from that of CSF, the brain accelerates, strikes the inner aspect of the rigid skull, and undergoes viscoelastic deformation. Analytical methods for a lumped parameter model of the brain predict internal brain motions that correlate well with published high-speed photographic studies. The same methods predict a …

Three-Photon Absorption Process In Organic Dyes Enhanced By Surface Plasmon Resonance, Ion Cohanoschi

Electronic Theses and Dissertations

Multi-photon absorption processes have received significant attention from the scientific community during the last decade, mainly because of their potential applications in optical limiting, data storage and biomedical fields. Perhaps, one of the most investigated processes studied so far has been two-photon absorption (2PA). These investigations have resulted in successful applications in all the fields mentioned above. However, 2PA present some limitations in the biomedical field when pumping at typical 2PA wavelengths. In order to overcome these limitations, three-photon absorption (3PA) process has been proposed. However, 3PA in organic molecules has a disadvantage, typical values of σ3' are small (10-81 …

High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen

Electronic Theses and Dissertations

In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism …

Designing Computer Agents With Facial Personality To Improve Human-Machine Collaboration, Brian Esley Tidball

Browse all Theses and Dissertations

The development of computer agents to enhance human-computer interfaces is an evolving field of study. This study examined whether people perceive personality in static digital faces that portray expressions of emotion, and if the digital faces would influence human performance on a simple human-machine collaborative task. The first experiment measured user-perception of personality, based on the emotional expression in two sets of five static digital faces. The results from this first phase revealed that participants provided different ratings, of the Big-Five personality model sub-traits, based on the emotional expression of a static digital face. This indicates a perception of personality …

Digital Channelized Wide Band Receiver Implemented With A Systolic Array Of Multi-Rate Fir Filters, David M. Rodney

Browse all Theses and Dissertations

This thesis proposes the use of a Systolic Array of Multi-Rate FIR Filters to improve performance by eliminating the requirement of the FFT and De-Multiplexer associated with the conventional receiver while achieving the same functionality. The FFT is a major bottle neck for improving system performance for the conventional DCWBR because many complex multiplications and additions are required. The proposed new architecture is designed and evaluated in MATLAB to illustrate its viability. Two approaches for improved channel arbitration are accessed in MATLAB, namely, channel bin’s rms comparison and parallelism of the Systolic Array Multi-Rate FIR Filters. The FIR filters (high-pass …

Fpga Frequency Domain Based Gps Coarse Acquisition Processor Using Fft, Cyprian D. Sajabi

Browse all Theses and Dissertations

The Global Positioning System or GPS is a satellite based technology that has gained widespread use worldwide in civilian and military applications. Direct Sequence Spread spectrum (DSSS) is the method whereby the data transmitted by the satellite and received by user is kept secure, low power and relatively noise-immune. The first step required in the GPS operation is to perform a lock on the incoming signal, both with respect to time synchronization and frequency resolution. Because of the need for reduced time to lock and also reduced hardware, algorithms based in the frequency domain have been developed. These algorithms take …

Cognitively-Engineered Multisensor Data Fusion Systems For Military Applications, Amanda Christine Muller

Browse all Theses and Dissertations

The fusion of imagery from multiple sensors is a field of research that has been gaining prominence in the scientific community in recent years. The technical aspects of combining multisensory information have been and are currently being studied extensively. However, the cognitive aspects of multisensor data fusion have not received so much attention. Prior research in the field of cognitive engineering has shown that the cognitive aspects of any human-machine system should be taken into consideration in order to achieve systems that are both safe and useful. The goal of this research was to model how humans interpret multisensory data, …

A Formal Language Approach For Detecting Texture Paths And Patterns In Images, Prithviraj S. Patil

Browse all Theses and Dissertations

This Master thesis considers the use of formal languages representation for image processing, especially texture patterns and determining texture paths in them. The texture paths are detected and extracted by using image processing techniques, such as image segmentation to isolate regions of interest, and then the extraction of repeating textures. The detection of the texture blocks is obtained by recursively using 27 X 27, 9 X 9, and 3 X 3 windows. Predefined repeating texture patterns are also searched for in each of the sets. For each set of texture blocks with similar or same characteristics, curve fitting techniques are …

Study Of Salt Wash Water Toxicity On Wastewater Treatment, Mostafa F. Hashad, Surabhi Sharma, Loring F. Nies, James E. Alleman

JTRP Technical Reports

This research effort focused on evaluating the toxicity of the saline waste water generated from washing of Indiana Department of Transportation (INDOT) deicing trucks and to study the feasibility of discharging it into wastewater treatment plants. Performance of activated sludge treating wastewater under varying levels of salt concentration was studied by measuring the Chemical Oxygen Demand (COD), activated sludge oxygen uptake rate (OUR) and Turbidity. For the COD tests, wastewater was tested with salt concentrations ranging from 0 mg/L – 1500 mg/L. Within this range there is no impact of salt on COD stabilization, suggesting that the microorganisms are not …

Filter Performance And Design For Highway Drains, Sangho Lee, Philippe L. Bourdeau

JTRP Technical Reports

The research is an investigation of soil filtration by geotextile fabrics, with the ultimate objective of improving design and long-term performance of underdrain systems in Indiana highways. Experiments were conducted in the laboratory using the best available techniques, Flexible Wall Gradient Ratio Test and Rapid Retention Test, in order to assess soil-filter compatibility and monitor geotextile clogging, for a range of materials and testing conditions. Field information was also collected and samples from highway reconstruction project were examined for their long-term performance. The main findings relate to the influence of the amounts of silt and clay and the state of …

E(Fg)2: A New Fixed-Grid Shape Optimization Method, Florin Bobaru Ph.D., Srinivas Rachakonda

Department of Engineering Mechanics: Faculty Publications

We propose a shape optimization method over a fixed grid. Nodes at the intersection with the fixed grid lines track the domain’s boundary. These “floating” boundary nodes are the only ones that can move/appear/disappear in the optimization process. The element-free Galerkin (EFG) method, used for the analysis problem, provides a simple way to create these nodes. The fixed grid (FG) defines integration cells for EFG method. We project the physical domain onto the FG and numerical integration is performed over partially cut cells. The integration procedure converges quadratically. The performance of the method is shown with examples from shape optimization …