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Articles 2881 - 2910 of 3180

Full-Text Articles in Engineering

Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager Aug 2007

Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager

Material Science and Engineering Theses - Archive

Several undisclosed fiberglass and carbon fiber laminates with toughened resin systems were tested and examined. Experiments were conducted to determine Modes I and II interlaminar fracture toughness for each of the nine laminates with varying types of processing forms such as roving, tape, and slit tape of glass and carbon fibers. Fractography was then used to correlate the fracture toughness results with the unique characteristics and failure mechanisms. Overall, fiberglass laminates had larger interlaminar fracture toughness for both Modes I and II over the carbon laminates. This was also confirmed by the significant amount of the fractured surface area and …

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Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure Aug 2007

Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure

Material Science and Engineering Theses - Archive

In the field of organic solar cell, the conjugated polymer-fullerene bulk heterojunction concept is one of the ongoing research interests. In this work, the use of de-oxyribose nucleic acid/ hexadecyl trimethyl ammonium chloride (DNA/CTMA) thin films as hole transport layer in poly(3-hexylthiophene)-methanofullerene (P3HT-PCBM) bulk heterojunction polymer solar cell is demonstrated. P3HT-PCBM bulk heterojunction polymer solar cell was fabricated with a DNA complex layer replacing commonly used PEDOT-PSS (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS). While PEDOT-PSS, as a hole transport and electron blocking layer, often improves the solar cell performance by improving fill factor, it requires careful engineering of spin-coating for the aqueous solution of …

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Complete Stress Analysis For Two Dimensional Inclusion Problem Using Complex Variables, Rohan Arun Patil Aug 2007

Complete Stress Analysis For Two Dimensional Inclusion Problem Using Complex Variables, Rohan Arun Patil

Mechanical and Aerospace Engineering Theses - Archive

This thesis addresses the problem of finding stresses and displacements in an infinite plate with a two dimensional circular inclusion with different material properties using complex variable method with biaxial loading acting on it. The complex variable method is used so that the continuity equations of traction force and displacement field are satisfied at the interface .All the complex equations are solved using software Mathematica.

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Stress Analysis Of An Ellipsoidal Inclusion, Mahesh Kailas Aug 2007

Stress Analysis Of An Ellipsoidal Inclusion, Mahesh Kailas

Mechanical and Aerospace Engineering Theses - Archive

The focus of the present thesis is to develop a mathematical model to calculate the stresses inside an ellipsoidal inclusion present in an infinitely extended matrix region and to validate the mathematically derived model by the Finite Element Method. To this end, a theoretical model has been developed to predict the stress inside an ellipsoidal inclusion. This model is based on equivalent inclusion method used to evaluate the stress distribution theoretically. Though there have been many theories to predict the stress distribution inside an ellipsoidal inclusion, its numerical validation is new despite its importance. A finite element model of a …

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Exploratory Studies Of Convective Flows Due To Arc Tracking, Richard R. Mitchell Aug 2007

Exploratory Studies Of Convective Flows Due To Arc Tracking, Richard R. Mitchell

Mechanical and Aerospace Engineering Theses - Archive

The objective of the research was to develop an understanding of how a flame propagates through an electronic enclosure. FLUENT®, a Navier-Stokes solver, was chosen due to its widespread commercial use, the availability of turbulence models and its ability to handle combustion. The relevance of this study with respect to the aerospace and domestic appliance industry was shown through case reports. Initial observations were made on arc discharges, chemical compounds and their relevance to establishing the flame. Experimental bench tests highlighted the instigating factors for flame ignition. The first round of bench testing revealed that solder node separation played an …

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Vehicular Emissions Models Using Mobile6.2 And Field Data, Abhishek Yerramalla Aug 2007

Vehicular Emissions Models Using Mobile6.2 And Field Data, Abhishek Yerramalla

Civil Engineering Theses - Archive

Regression models to predict vehicular emissions for different categories of vehicles for different pollutants are presented in this thesis. Vehicular emissions are affected by numerous variables which, among others, include speed, temperature, acceleration, deceleration, driving behavior and meteorological data. Regression models are developed based on data obtained from Mobile 6.2 and on-board emissions measurements. The U.S. Department of Transportation (US DOT) conducted sensitivity analysis of Mobile6 where they evaluated different parameters used to find the emission factors, such as vehicle miles traveled, speed, humidity, etc. The sensitivity analysis investigated the overall Mobile6.2 model behavior for various conditions. In the analysis, …

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Large Array Emg Monitoring Of Lumbar Region Muscle Action In Discogenic Low Back Pain, Jazzmyne Ann Richardson Buckels Aug 2007

Large Array Emg Monitoring Of Lumbar Region Muscle Action In Discogenic Low Back Pain, Jazzmyne Ann Richardson Buckels

Bioengineering Theses - Archive

This project explored the use of large array surface electromyography (LASE) as a technique for assessing the patterns of muscular activity under standardized loading conditions in patients with lumbar disc related pain and healthy subjects. Specifically, the project evaluated quantitative parameters of visually observed patterns of muscle action proposed to clinically discriminate between groups. If such correlates exist, then, this work may lead to technology assessment for sensitivity and specificity as a diagnostic procedure. Solutions to the issues for determining the effects of low back pain (LBP) on force and moment generation in the spine as well as its effect …

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A Functional Analysis Of The Mechanically And Metabolically Sensitive Components Of The Skeletal Muscle Exercise Pressor Reflex In Hypertension, Anna Katherine Leal Aug 2007

A Functional Analysis Of The Mechanically And Metabolically Sensitive Components Of The Skeletal Muscle Exercise Pressor Reflex In Hypertension, Anna Katherine Leal

Bioengineering Theses - Archive

Background - In hypertension, physical activity creates a risk for adverse cardiac events by causing exaggerated increases in mean arterial pressure (MAP) and heart rate (HR). One physiological mechanism responsible for this cardiovascular hyperactivity is the exercise pressor reflex (EPR). The EPR is a neural pathway originating in skeletal muscle that contributes to cardiovascular regulation during exercise. The EPR is composed of two afferent arms: one is comprised of mostly mechanically sensitive, group III afferent fibers that respond to muscle stretch and pressure, and the other is predominantly metabolically sensitive, group IV afferent fibers that respond to the chemical milieu …

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Development Of A Broadband Multi-Channel Nirs System For Quantifying Absolute Concentrations Of Hemoglobin Derivatives And Reduced Scattering Coefficients, Dheerendra Kashyap Aug 2007

Development Of A Broadband Multi-Channel Nirs System For Quantifying Absolute Concentrations Of Hemoglobin Derivatives And Reduced Scattering Coefficients, Dheerendra Kashyap

Bioengineering Dissertations - Archive

Near infrared spectroscopy (NIRS) has been widely applied to investigate hemoglobin oxygenations of muscles, brain and breast tumors. Steady state reflectance techniques developed previously have been restricted to determination of relative concentrations. To overcome these limitations, this dissertation describes the development, validation and applications of broadband, steady-state, optical spectroscopic systems and algorithms to quantify absolute concentrations of hemoglobin derivatives and reduced light scattering coefficients using (1) thin optical probes with small (100 μm - 1 mm) source-detector separations and (2) a large separation (< 4 cm) probe.. A recently developed mathematical model by Zonios and Dimou for reflectance at small source-detector separations was used to develop techniques to quantify chromophore concentrations and light scattering coefficients (Chap. 2). Blood-intralipid phantom models were used to determine empirical coefficients to model reflectance spectra. This technique was further applied to quantify hemodynamic changes during formalin- induced pain behaviors in rats (Chap. 3). To overcome limitations in penetration depth and investigated tissue volume, another approach to quantify concentrations of chromophores in tissues at large source-detector separations was also developed. This novel approach uses the process of second differential spectroscopy to quantify concentrations of deoxygenated hemoglobin with respect to the tissue water content. Based on such quantification, an adaptation of the ant colony optimization algorithm was utilized to quantify absolute concentrations of other constituent tissue chromophores. The developed techniques were validated with the reflectance measurements from blood-intralipid phantoms and further applied to monitoring of ex vivo human prostate lesions and of rat brain tumor growth in vivo (Chap. 4). In the second stage of my doctoral development, a multi-channel, broadband, steady-state, NIRS imaging system was developed to determine spatial distributions of hemoglobin concentrations and reduced light scattering coefficients. The imager was calibrated with laboratory phantoms to eliminate deterministic instrumentation bias of CCD-spectrometers, optical fibers, and multiplexer channels. Calibration procedures also include determinations of the source strength and boundary coefficients in order to obtain accurate image reconstructions. A multi-wavelength, spectrally constrained reconstruction algorithm was developed to obtain tomographic maps of hemoglobin derivative concentrations and reduced scattering coefficients, using laboratory tissue phantoms. The developed imaging system and reconstruction algorithms were validated with both static and dynamic multi-tube phantoms.

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Resolution And Localization In Single Molecule Microscopy, Sripad Ram Aug 2007

Resolution And Localization In Single Molecule Microscopy, Sripad Ram

Bioengineering Dissertations - Archive

Rayleigh's criterion is extensively used in optical microscopy to determine the resolution of microscopes. Despite its widespread use, it is well known that this criterion is based on heuristic notions and can be surpassed in a regular optical microscope. The inadequacy of Rayleigh's criterion has necessitated a reassessment of the resolution limits of optical microscopes. The thesis proposes a new resolution criterion that overcomes the limitations of Rayleigh's criterion. The new result predicts that there is no resolution limit, but that the resolvability depends on the number of detected photons. Analytical tools are introduced to estimate the distance from microscopy …

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Spatial Resolution And Biliary Tissue Classification Properties Of A Near Infrared Light Imaging Probe, Praveen Kumar Gulaka Aug 2007

Spatial Resolution And Biliary Tissue Classification Properties Of A Near Infrared Light Imaging Probe, Praveen Kumar Gulaka

Bioengineering Theses - Archive

Approximately 500,000 Gallbladder Surgeries or Laparoscopic Cholecystectomies are performed annually to remove the Gallbladder. This surgery becomes necessary due to formation of gall stones. As biliary tract tissues are embedded in fat, differentiating them from neighboring tissues and blood vessels is critical in helping surgeons during laparoscopic cholecystectomy to avoid post-surgical complications. Optical spectroscopy (in both visible and near infrared regions) is investigated as a possible technique to identify biliary tract tissues and blood vessels. Such reflectance measurements provide information of effective attenuation, which is an index of optical properties of the tissue.Specifically, optical reflectance measurements were made on biliary …

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Experimental And Field Monitoring Studies On Recycled Materials As Pavement Bases, Sunil Kumar Sirigiripet Aug 2007

Experimental And Field Monitoring Studies On Recycled Materials As Pavement Bases, Sunil Kumar Sirigiripet

Civil Engineering Theses - Archive

Natural aggregates derived from a variety of source rocks have been used as a road base material. But the extraction of natural aggregates resources is increasingly being constrained by urbanization, increased costs and environmental concerns. Thus, increased amounts of reclaimed materials are being used to supplement natural aggregates in road construction. Recycled Asphalt Pavement (RAP) material is one of the important recycled materials used in the present geotechnical applications. Many agencies are constantly seeking to reap the benefits of utilizing RAP. Main advantages of utilizing RAP include the preservation of the existing profile, conservation of asphalt and aggregate resources, conservation …

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The Travel Behavior Of Minority Cohorts In Texas, Gustavo A. Jimenez Vera Aug 2007

The Travel Behavior Of Minority Cohorts In Texas, Gustavo A. Jimenez Vera

Civil Engineering Theses - Archive

Texas is changing dramatically; the most conservative population forecast indicates that Hispanics will account for 50% of the Texas population before 2035. Not only is the number of Hispanics on the rise in Texas, but also the foreign-born share has increased dramatically over the last 15 years. The State of Texas is now a majority minority state, and minority cohorts are expected to grow and become more than 65% of the Texas population before 2035. Transportation professionals in the State of Texas are wondering how these demographic changes will affect the transportation system. To gain an understanding of this, one …

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Cmos Vco & Lna Implemented By Air-Suspended On-Chip Rf Mems Inductors, Varun K. Shenoy Aug 2007

Cmos Vco & Lna Implemented By Air-Suspended On-Chip Rf Mems Inductors, Varun K. Shenoy

Electrical Engineering Theses - Archive

In this thesis, a CMOS 2.4 GHz Low noise amplifier (LNA) and Voltage-controlled oscillator (VCO) was designed and simulated. These circuits were designed to operate in the 2.4GHz Industrial Scientific Medicine (ISM) band and to achieve Bluetooth and Wifi standard specifications. High-Q RF MEMS air-suspended circular spiral inductors are used in both circuits. High-Q inductors give the circuit better performance parameters including higher gain, lower noise figure and narrower bandwidth. The integration of these RF MEMS inductors onto RF circuit chips was carried out using the UV-LIGA technique and an additive pattern transfer technique such as electroplating. The LNA maintains …

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Spatially Resolving Spectrometer For Characterisation Of Broad-Area Laser Diodes, Sheldon Fernandes Aug 2007

Spatially Resolving Spectrometer For Characterisation Of Broad-Area Laser Diodes, Sheldon Fernandes

Electrical Engineering Theses - Archive

The mode pattern of the BALD (Broad-Area Laser Diode) is characterized and measured using a 1-GHz resolution double-pass spectrometer. The design of spectrometer allowed also a spatial discrimination with 1mkm resolution. The construction and design of the double-pass grating is analyzed and discussed. A matrix approach is developed for the double-pass measurement arrangement. The developed procedure of analysis of spatially resolved spectra provides unique information about broad-area laser diode active medium and cavity geometry and potentially will help to predict the reliability of the laser diode. The developed model is based on paraxial approximation. The laser diode modes are measured …

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Fabrication Of A Silicon Single Electron Transistor, Sharukh Roomy Chinoy Aug 2007

Fabrication Of A Silicon Single Electron Transistor, Sharukh Roomy Chinoy

Electrical Engineering Theses - Archive

Single electronics has bright prospects because of its high scalability. The single electron transistor (SET) which utilizes these principles could replace the current workhorse of the industry, the MOSFET. The SET is plagued with limitations such as, a low operating temperature, background charge issues, a low voltage gain and high output impedance. The current generation SET devices have overcome most of the aforementioned issues but use highly complicated fabrication techniques. Electron beam lithography was used to pattern device structures on silicon-on-insulator (SOI) wafers with a hydrogen silsesquioxane (HSQ) system being the resist. The silicon was then etched using HSQ as …

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A Potential Field Approach To Multiple Robot Formation Control, Rohit Santosh Talati Aug 2007

A Potential Field Approach To Multiple Robot Formation Control, Rohit Santosh Talati

Electrical Engineering Theses - Archive

A special case of cooperative control for mobile robots is considered - formation control. A potential field based algorithm is developed in which geometric, communication and information centric influences are considered and allowed to deform the formation. Control is accomplished in a leader-follower(s) method. One leader robot defines the overall trajectory and follower nodes individually and autonomously maintain the formation while simultaneously moving toward a goal position. The particular nodes considered are the ARRIbots developed at the Distributed and Intelligence and Autonomy Lab (DIAL) in the Automation and Robotic and Research Institute (ARRI), which are non-holonomic differential-drive wheeled robots. In …

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Characterization Of A Hyperspectral Imager: A Diagnostic Tool For Monitoring Retinal Diseases, Nirad Zinzuwadia Aug 2007

Characterization Of A Hyperspectral Imager: A Diagnostic Tool For Monitoring Retinal Diseases, Nirad Zinzuwadia

Bioengineering Theses - Archive

We developed a novel hyperspectral slit lamp ophthalmoscope for visualizing vascular changes for clinical monitoring of retinal diseases, for example, diabetic retinopathy. The device consists of a visible charge couple device, CCD, and liquid crystal tunable filter, LCTF, coupled to the standard clinical slit lamp ophthalmoscope. The LCTF is used as a spectral light source illuminating the retina with different wavelengths of light that are recorded by the CCD and stored as a series of wavelength dependent images of the retina. Chemometric analysis produces a gray scale encoded image for the percentage of oxyhemoglobin at each pixel within the field …

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Roadway Shallow Water Flow Modeling By Velocity Distribution, Chirakarn Sirivitmaitrie Aug 2007

Roadway Shallow Water Flow Modeling By Velocity Distribution, Chirakarn Sirivitmaitrie

Civil Engineering Dissertations - Archive

Manning's equation is a widely used method for determining flow discharge in a channel with unconfined gravity flow. The roughness value, n-value, is a critical factor for Manning equation to obtain the accurate amount of flow. A precise estimation of Manning "n" is difficult to obtain and varies by investigator justification and experience. Flow on a roadway is a type of open channel flow normally determined by Manning's equation. To ensure reliability and highway safety, the hydraulic geometry dimensions such as spread, depth and discharge must be accurately estimated. A Texas Department of Transportation Manning n-value research project collected data …

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Discrete Event Controller: Application Using Dynamic Resource Allocation, Abhishek Trivedi Aug 2007

Discrete Event Controller: Application Using Dynamic Resource Allocation, Abhishek Trivedi

Electrical Engineering Theses - Archive

This work consists of developing a Discrete Event Controller with Dynamic Resource Allocation, simulating it and than applying it on a test-bed using robots and static sensor nodes. These are the contributions made: 1. Interfacing the Garcia robot with Mica2/Cricket Sensor. 2. Implementing Obstacle Avoidance and Path planning on Garcia Robot for navigational purposes. 3. Localizing the Garcia Robot with the help of Cricket sensor and controlling it from the Base Station to perform assigned tasks. 4. Simulating a Discrete Event Controller which dynamically coordinates multiple missions and simultaneously performing dynamic resource assignment and solving any shared resource conflicts. 5. …

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Optimized Class-E Rf Power Amplifier Design In Bulk Cmos, Tao Wang Aug 2007

Optimized Class-E Rf Power Amplifier Design In Bulk Cmos, Tao Wang

Electrical Engineering Theses - Archive

The telecommunication market calls for the integration of complicated wireless applications. To build RF power amplifiers in CMOS remains challenging due to the nonideal effects in CMOS. The aim of this thesis is to provide an optimized yet explicit design method for the Class-E amplifiers in CMOS. Taking the finite DC feed inductor into consideration, a simple but accurate numerical design method is proposed by applying polynomial interpolation. Combining with a practical design stategy for nonideal transistors of finite conductance and parasitic capacitances, a two-staged Class-E power amplifier is implemented in 0.18um CMOS. The simulation results show that this power …

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Detection Of Positive Cancer Margins Intra-Operatively During Nephrectomy And Prostatectomy Using Optical Reflectance Spectroscopy, Disha Laxman Peswani Aug 2007

Detection Of Positive Cancer Margins Intra-Operatively During Nephrectomy And Prostatectomy Using Optical Reflectance Spectroscopy, Disha Laxman Peswani

Bioengineering Theses - Archive

In recent years optical spectroscopies have become the basis for popular research activity directed towards the development of novel, noninvasive technologies for tissue diagnostics. The motivation for my research was to eliminate the need for surgical removal of tissue samples for biopsy and histology. With the help of an optical probe placed on or near the surface of the tissue, Near Infrared (NIR) spectroscopy can provide diagnostic signatures, non-invasively and in real time. While the ultimate goal vi is the elimination of the need to remove tissue samples, this technology can also be used to provide additional guidance during laparoscopic …

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Foreign Body Reactions To Neural Implants In The Brain, Parisa Lotfi Aug 2007

Foreign Body Reactions To Neural Implants In The Brain, Parisa Lotfi

Bioengineering Theses - Archive

Neural implants have been used and studied for many decades. They are applied to record neural signals or to locally deliver drugs. Unfortunately, foreign body reaction and accompanied glial scar formation often lead to implant failure. The lack of knowledge about the molecular mechanism governing foreign body reactions in the brain significantly hinders the development of brain implantable devices with improved safety and biocompatibility. To study the immune responses to brain implants, a novel animal model has been developed and used for the following investigation. Our studies have established cell recruitment time courses of astrocytes, microglial cells, lymphocytes, monocytes and …

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Functionalized Nanoparticles For The Selective Killing Of Cancer Cells, Paul Todd Thevenot Aug 2007

Functionalized Nanoparticles For The Selective Killing Of Cancer Cells, Paul Todd Thevenot

Bioengineering Theses - Archive

The use of nanoparticles for cancer imaging and drug delivery has produced some success in improving the efficacy and safety of cancer chemotherapy. It is generally believed that the efficiency of nanoparticle-based cancer therapy would be greatly improved if such particles could be designed to directly interact with and eradicate tumor. Many recent studies have revealed that surface functionality plays an important role in particle:cell interactions. Using titanium dioxide (TiO2) nanoparticles (21 nm diameter) as test subjects, nanoparticles with different functional groups, hydroxyl (-OH), amine (-NH2), and carboxyl (-COOH) were produced and used in this investigation. An in vitro cell …

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Cytotoxic Evaluation And Factorial Analysis Of 3d Photopolymerizable Thermoresponsive Composite Nanoparticle Hydrogels For Controlled Drug Delivery In Restenosis And Wound Healing, Abhimanyu Rajaram Sabnis Aug 2007

Cytotoxic Evaluation And Factorial Analysis Of 3d Photopolymerizable Thermoresponsive Composite Nanoparticle Hydrogels For Controlled Drug Delivery In Restenosis And Wound Healing, Abhimanyu Rajaram Sabnis

Bioengineering Theses - Archive

To develop a smart drug delivery system for restenosis and wound healing applications, we investigated photopolymerizable composite nanoparticle hydrogels which can release the drug in a temperature-responsive manner. Our novel system consisting of thermoresponsive poly(N-isopropylacrylamide-co-acrylamide) (PNIPA-AAm) nanoparticles and poly(ethylene glycol) diacrylate (PEGDA) as photo cross-linker can be formed in situ in presence of ultraviolet (UV) light and Irgacure 2959 photoinitiator (PI). The main aims of this project were to investigate the system cytotoxicity and optimize drug release characteristics by performing biocompatibility and factorial analysis studies, respectively. We evaluated the cell survival of human vascular smooth muscle cells and NIH/3T3 fibroblasts …

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Investigation Of Brain Activities Using Two State-Of-The-Art Diffuse Optical Imagers, Suresh Prajapati Aug 2007

Investigation Of Brain Activities Using Two State-Of-The-Art Diffuse Optical Imagers, Suresh Prajapati

Bioengineering Theses - Archive

Near-Infrared Spectroscopy (NIRS) and diffuse optical imaging (DOI) are increasingly used to detect hemodynamic changes in the cerebral cortex induced by brain activity. The new commercially available DOI systems CW5 and DYNOT have large number of sources and detectors; by arranging them in specific patterns, one can cover most of the adult head. This study is a preliminary step in understanding CW5 and DYNOT and exploring their capabilities for various purposes. My work is divided in to three major parts. The first goal of this study was to study changes in hemodynamic response of brain during Breath holding, using both …

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Gas Permeation Through Nanoporous Polycarbonate Track- Etched Membranes: Pulsed Plasma Polymerization Of Thin Coatings To Modulate Gas Permeability, Christopher Lewis Chapman Aug 2007

Gas Permeation Through Nanoporous Polycarbonate Track- Etched Membranes: Pulsed Plasma Polymerization Of Thin Coatings To Modulate Gas Permeability, Christopher Lewis Chapman

Bioengineering Theses - Archive

Polycarbonate track-etched membranes (PCTE) of 50nm and 100nm pore size, precoated with Poly Vinyl Pyrrolidone (PVP), were surface treated with either Vinyl Acetic acid (VAA) or Perfluorohexane (C6F14) using a low duty cycle pulsed plasma polymerization technique. The effects of this surface treatment on gas permeation properties of the PCTE were addressed. Plasma coating thickness was controllably varied and resulted in gradual reduction of O2 and CO2 permeability as thickness increased from 10nm to 100nm. Plasma coating material, permeant gas, membrane pore size, and crosslink density were also varied in order to gain insight into the permeation properties of the …

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Evaluation And Applications Of Gas Sensors, Hung Viet Cao Aug 2007

Evaluation And Applications Of Gas Sensors, Hung Viet Cao

Electrical Engineering Theses - Archive

Gas sensors are used widely for environmental and biomedical uses. This work focuses on verifying specifications of commercial-off-the-shelf (COTS) gas sensors and their particular applications. The first chapter in this thesis gives a literature review on gas sensors, especially metal-oxide based sensors and their advantages. The second chapter focuses on evaluation of COTS NO2 sensors. The purpose is to establish a characterization method to evaluate gas sensors. I have evaluated three COTS metal-oxide based NO2 sensors and a COTS electrochemical sensor for comparison. Four different tests have been implemented to investigate the sensitivity, humidity effects, temperature effects, and selectivity for …

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Design And Simulation Of An Accurate Breast Biopsy System, Sumit Tandon Aug 2007

Design And Simulation Of An Accurate Breast Biopsy System, Sumit Tandon

Electrical Engineering Theses - Archive

Core needle biopsy is a non-invasive technique for confirming breast and prostate cancer. Over the years, several non-real time image guided systems have been developed to guide the needle to the target lesion/tumor. Frequently used methods are those employing x-ray, ultrasound, MRI or x-ray fluoroscopy to guide the needle during biopsy. However, these methods suffer from the disadvantages that they are non-real time or the imaging technique is two dimensional or ionizing. Our broad objective is to develop a visually guided, haptic assisted breast biopsy system (henceforth called ViHAB) using real time 3D ultrasound imaging and haptic guidance. The system …

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System And Method For The Pooling Of Sterile Product, David A. Edelen Aug 2007

System And Method For The Pooling Of Sterile Product, David A. Edelen

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

This dissertation defines an automated system and method for removing the tops from individual sealed bottles and pooling the small volumes of liquid contained in each bottle together in a collection container while maintaining the sterility of the product. This research further applied system development and process improvement methodology. More particularly, this research solved a previously unsolved problem through the unique research and development, and application of ultrasonic technology, to mitigate both product and personnel risk, and provide process improvement, as associated with the aseptic process for the pooling of sterile product.

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