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Analysis Of The Dynamics Of Vasomotion Using Laser Doppler Flow, Shruthi Raj

Bioengineering Theses - Archive

Vasomotion is a phenomenon caused by changes in the diameters of blood vessels. It is due to the contractile activity of small arteries and arterioles resulting in periodic changes of blood flow in the skin. These flow variations in the arteries are reflected by the Laser Doppler Flowmeter. The goal of the skin blood flow (blood perfusion) study is to establish a method to analyze and quantify the pattern of vasomotion as detected using Laser Doppler Flow (LDF). Spectral analysis of the LDF signal reveals the presence of periodic components in the vascular system. The study involves twelve subjects of …

Performance Evaluation Of Bamboo Reinforced Concrete Beams, Leena Khare

Civil Engineering Theses - Archive

This study presents the evaluation of the feasibility of the use of bamboo as a potential reinforcement in concrete structural members. To achieve this objective a series of tensile tests on three types of bamboo Solid; Moso; and Tonkin; were conducted to obtain their constitutive relation. Also, four-point bending tests on concrete beams reinforced with bamboo were performed to identify their behavior compared to steel reinforced concrete members. Tensile tests specimens were prepared by cutting the bamboo typically in 1/2 in (13 mm) wide strips of 9 to 12 in (228 mm to 305 mm) in length. In order to …

Performance And Check-Out Verification Testing Of A New True Triaxial Apparatus Using Partially Saturated Silty Sand, Jae Hyun Park

Civil Engineering Theses - Archive

A stress-controlled, flexible boundary, true triaxial (cubical) testing apparatus has been developed to test 3-inch cubical specimen of partially saturated soil under different moisture contents and for a wide range of multiaxial stress paths. A series of HC, CTC, TC, TE, and SS tests were conducted in order to perform a thorough performance and check-out verification testing of the newly developed device by investigating the multiaxial stress-strain response of partially saturated silty sand specimens artificially prepared in the laboratory. The development of the apparatus, specimen preparation process, test procedure, and the corresponding validation of its suitability for testing partially saturated …

Modeling And Characterization Of A Fabry Perot Pressure Sensor, Shruthika Prasanna

Electrical Engineering Theses - Archive

Fabry-Perot interferometers (FPIs) have been used as sensing elements for pressure transducers in many applications. Most of the current FPI pressure sensors measure amplitude changes of the reflected signals from a deformable diaphragm. A new technique to design an FPI pressure sensor has been proposed in this thesis. The proposed methodology aims to maximize the sensitivity by measuring frequency shifts and optimize the dimensions of the sensors for various materials and applications. The sensor diaphragm is built directly on the end surface of an optical fiber with a sacrificial layer introducing the required FPI cavity height. The resulting sensor detects …

Physics Based Time-Frequency Analysis To Reduce Multi-Bounce And Clutter In Radar Imaging, Anilkumar Kollipara

Electrical Engineering Theses - Archive

The concept of time-frequency analysis of the scattered far field data from multiple targets is presented. The scattered data from the target is collected using a mono-static antenna configuration. The hardware system and the data acquisition system used in the process are discussed in detail. The results obtained using the ISAR imaging algorithm are presented and the effect of different non-point and dispersive scattering phenomena on these images are discussed. A physics based time-frequency analysis using wavelets is done on this scattered data to reduce the inter-target interactions and thereby produce cleaner images of the target under consideration. The results …

Optical Amplifiers For 10 Gb/S Wdm Recirculating Loop Testbed, Sravanthi Thotakura

Electrical Engineering Theses - Archive

This Master's thesis deals with building experimental setup for characterization of novel nonlinear optical devices for fiber communication. The first part of the thesis deals with the description of the theoretical basis for operation of a particular type of such nonlinear optical devices, namely a parametric amplifier. Document includes deriving and solving the equations for parametric amplification in optical fiber when signal, idler and pump beams are linearly co-polarized. We consider both non-degenerate and degenerate pump cases for arbitrary phase mismatch. In the second part of the thesis we present the design and experimental implementation of electrical interface between commercial …

Time Synchronization In Network-Centric Sensor Networks, Sejal D. Raje

Electrical Engineering Theses - Archive

Time synchronization is a crucial component of infrastructure for wireless sensor networks (WSN). Most applications of WSNs make extensive use of time synchronization, for accurate timestamping of events, coordinate activities of the network, data fusion, object tracking or TDMA scheduling. The unique requirements of sensor networks in terms of precision, lifetime, energy and scope of the synchronization achieved, calls for design of new synchronization methods for WSNs. In this thesis, we describe the design of three novel techniques for achieving synchronization in network centric scenario of sensor networks: sequential least squares, Kalman filter and fuzzy logic systems. The strength of …

Collision Response For Virtual Laparoscopic Surgery, Jitesh Devidas Butala

Electrical Engineering Theses - Archive

During laparoscopic surgery the surgeon operates inside the abdomen guided by the 2D imagery of the operating area. This image is obtained via a camera inserted through a small incision. Laparoscopic surgery, in contrast to open surgery, results in low pain and recovery time for the patient. However, the surgeons have some difficulty, as the training required for this type of surgery is more intense and rigorous than that for conventional open surgery. Hence, surgical trainers for laparoscopic surgery are important. The main difference in the different types of surgical trainers is the degree to which the actual environment of …

First Observation Of Dijet Events With An Antiproton Tag At [Square Root]S = 1.96 Tev Using The Dø Forward Proton Detector, Michael Strang

Physics Dissertations - Archive

The Forward Proton Detector (FPD) is a new sub-system of the DØ detector, a 5000 ton particle physics detector located at the Fermilab Tevatron proton-antiproton collider. The FPD was implemented for the Tevatron Run II and gives access to a wide range of diffractive scattering processes, where one or both of the beam particles remain intact. The analysis described in this thesis makes use of the dipole spectrometer of the FPD to tag outgoing antiprotons in events that have a dijet signature in the central D0 calorimeter. Properties of jets with a diffractive tag signature are compared to jets without …

Surface Functionalization Of Polymer Substrates And Nanoparticles Via Pulsed Plasma Polymerization Process, Jing Wu

Chemistry & Biochemistry Theses - Archive

This thesis investigates the RF plasma polymerizations of chlorinated saturated linear monomer 1,1,1-trichloroethane and the dicarboxylic citraconic acid. It utilizes a variable duty cycle plasma technique to provide film chemistry control during the plasma polymerization process. Film chemical compositions and deposition rates were characterized as functions of the plasma processing conditions. In each system studied, spectroscopic analyses revealed that large progressive changes in film compositions were obtained with sequential variations in plasma duty cycles in the plasma polymerization of both 1,1,1-trichloroethane and citraconic acid. The plasma approach was also employed to modify the surfaces of nanoparticles. Thin polymeric films, produced …

Structure & Decision In Mobile Wireless Sensor Networks, Prasanna Mohan Ballal

Electrical Engineering Theses - Archive

This work concerns the development of a novel structure of Discrete Event Controller (DEC) for mobile wireless sensor networks consisting of mobile robots and stationary wireless sensing nodes known as Unattended Ground Sensors (UGS). These are the three contributions: 1. Decision-making systems such as Fuzzy Logic and Dempster Shafer Theory for sensor fusion are implemented. 2. Decision-making is used for a special case of routing of resources for multiple tasks performed by different resources. 3. The DEC was actually implemented in the Mobile Wireless Sensor Networks lab at Automation & Robotics Research Institute. This work was supported by ARO grant …

Vascular Stent Analysis, Tre Raymond Welch

Bioengineering Theses - Archive

It is important for cardiologist to understand the stresses and strains the stent experiences during deployment. We created a 3-D model of the coiled stent which is exported into ANSYS creating the finite element model. The stent material is Poly-L-Lactic Acid (PLLA) fiber with a Young's modulus of 7043(MPa) and a Poisson's ratio of 0.35. A nonlinear material analysis simulates the material behavior through plastic deformation during expansion from 1(atm) to 14(atm). The von Mises stresses, principal stresses, and principal strains are analyzed to determine the yielding of the PLLA fiber. Also, the effect of different material properties including Young's …

Near Infrared Spectroscopy: A Study Of Cerebral Hemodynamics During Breathholding And Development Of A System For Hot Flash Measurement, Vikrant Sharma

Bioengineering Theses - Archive

Near Infrared (NIR) spectroscopy and imaging has become popular in research fields for the past 2-3 decades. My research focuses on the continuous wave near infrared imaging technique. The work consists of two main parts. In the first part, an existing commercial system, an LEDI (Light Emitting Diode Imager), is used to study the cerebral hemodynamics during breath holding. The aim was to evaluate the ability of an LED-based continuous wave imager to capture changes in hemodynamics occurring inside the skull induced by breath holding. The study involved 15 human subjects. It was found that the total hemoglobin concentration (in …

Dynamic Modeling Of Cerebral Blood Flow Autoregulation Using Arx And Windkessel Models, Piyush Gehalot

Bioengineering Theses - Archive

Linear lumped parameter models like ARX and Windkessel models are simple, easy to solve, and find their application in real time modeling. The present study is focused on employing single input single output ARX and Windkessel models to beat-to-beat mean arterial blood pressure (MABP, mmHg) considered as input to the model, and cerebral blood flow velocity (CBFV, cm/sec) considered as output of the model. For some models and modeling methodologies, the data consisted of cerebral perfusion pressure (CPP, mmHg, estimated from MABP) and CBFV. The data was measured from 10 healthy normal subjects while the subjects performed Valsalva maneuver with …

Feasibility For Utilization Of A Freshwater Pulmonate Snail, Physa Acuta, As A Model Organism For Environmental Toxicity Testing, With Special Reference To Cadmium Ion Toxicity, Valerie Woodard

Biology Dissertations - Archive

The benefits of developing the pond snail, Physa acuta, as a model species for testing acute and chronic toxicity of aquatic pollutants include its wide North American distribution, ease of field collection and laboratory maintenance, and efficacy in testing toxicity responses including mortality, crawling behavior, reproduction and metabolism under both field and laboratory conditions. Mortality, as 50 % sample lethal concentration (LC50) and 50 % sample lethal time (LT50) values with increased cadmium chloride (CdCl2) concentration in both acute 192 h and chronic 672 h tests. A new endpoint of 50 % sample crawl-out response (CO50) proved to be a …

Use Of Reovirus Monoreassortants To Define Lysis Of Transfomed Cells, Christine Nora Mutsoli

Biology Theses - Archive

Reovirus is known to selectively destroy transformed cells while establishing a persistent infection in normal cells. For this study the transformed cell lines used were L929, WI-38 VA13 2RA, T1, N1, and MYC-3. Additionally, the normal cells WI-38 and MMEC were used to examine differential sensitivity to reovirus serotypes 1, 2, and 3. Reovirus is able to replicate efficiently in L929 cells because it induces a transition from capped to uncapped translation of viral mRNA. Reovirus maintains a persistent infection in WI-38 cells, but lyses WI-38 VA13 2RA cells. Reovirus has also been demonstrated to lyse and produce more virus …

Using A Structural Equation Model To Examine Child Maltreatment Potential Across Ecological Systems In A Population Of Families In Poverty, Cynthia Lorraine Juby

Social Work Dissertations - Archive

This study was a secondary analysis designed to examine the ecological system indicators of child maltreatment potential. A total of 263 families living within 200% of the poverty level were included in the sample. Results of the study revealed the exosystem indicator of social support had the greatest impact on child maltreatment while maltreatment of the parent as a child (history of maltreatment), an ontogenic system indicator, was the second highest predictor. Additionally, these two indicators were highly correlated within the structural model. The microsystem indicator of parental educational attainment and the macrosystem indicator of belief in corporal punishment had …

Direct Numerical Simulation For Flow Transition Over A Flat Plate, Shutian Deng

Mathematics Dissertations - Archive

In this paper, direct numerical simulation (DNS) of flow transition over a flat plate at a free stream Mach number of 0.5 and a Reynolds number of 1000 based on the free stream velocity and inflow displacement thickness has been carried out. The time-dependent Navier-Stokes equations are solved directly by a third-order TVD Runge-Kutta method from Shu(1998). A sixth order central compact scheme from Lele (1992) that facilitates high resolution of the flow field is used for spatial discretization together with a sixth order implicit compact filter. To avoid possible non-physical wave reflection from the boundaries, the non-reflecting boundary conditions …

On The Image Of The Totalling Functor, Kristen Ann Beck

Mathematics Theses - Archive

Let A denote a DG algebra and k a field. The totalling functor, from the category of chain complexes over the graded A-modules to the catagory of DG modules over A, can be extended to one between their derived categories. If this extension were onto, the derived category of the category of DG modules would be superfluous. This paper investigates the image of the extension of Tot in the fundamental case when A is the polynomial ring in d variables over k. When d is at least 2, there are semifree DG modules of rank n, where n is at …

A Framework For Supporting Quality Of Service Requirements In A Data Stream Management System, Qingchun Jiang

Computer Science and Engineering Dissertations - Archive

Currently, a large class of data-intensive applications, in which data are presented in the form of continuous data streams rather than static relations, has been widely recognized in the database community. Not only is the size of the data for these applications unbounded and the data arrives in a highly bursty mode, but these applications have to conform to Quality of Service (QoS) requirements for processing continuous queries (CQs) over data streams. These characteristics make it infeasible to simply load the arriving data streams into a traditional database management system and use currently available techniques for their processing. Therefore, a …

Mcpherson County, Sd Air Photos (1939 + Field Notes), Plant Science Department

South Dakota Counties Aerial Photos Collection

Pedology CD 05-14
This file contains 145 images from 1939 of McPherson County, SD.

The photos are from McPherson (1939 + Field Notes) County, SD. No index map was prepared for the photos. The scale of the original photos was 1:20,000 or 3.17 inches = 1 mile. The inventory of images does not represent coverage of the entire county. The images contained in this file represent part of the air photo collection for Meade County, SD that the South Dakota State University (SDSU) Pedology Project had on July 2005.
The structure of the files is as follows:

1. There is a …

An Evaluation Of Religion And Spirituality In Social Work Education, Sharina Nicole Branum

Social Work Theses - Archive

This study evaluated how BSW students at two Texas universities, one publicly funded and one privately funded, perceive their level of preparedness, comfort and the importance of addressing / using religion and spirituality in social work. In this study 41 students nearing the completion of their baccalaureate degree and enrolled in a field placement, were invited to complete a multi-faceted questionnaire consisting of 92 very specific questions. Of the 41 students invited to participate in the study, all subjects chose to complete the questionnaire. The questionnaire used gathered some information regarding the students' personal religious and spiritual affiliation however, the …

On A Class Of Abcs, Sridevi Lalgudi Ganapathy

Physics Theses - Archive

The local density approximation to density functional theory (LDA-DFT) has been used to study the different possible relaxations and reconstructions of In-rich InSb (100) surface. Various electronic and geometric structure properties such as, bond lengths, cohesive energies, band gaps and density of states of the ideal (1x1) surface and the (2x1), (4x2) and c(8x2) reconstructed InSb surfaces are reported. Adsorptions of lithium atom as well as other halogen atoms such as chlorine, bromine and iodine on the (1x1), (2x1), (4x2) and c (8x2) InSb surfaces in the different symmetric sites, such as, top, bridge, hollow, cave, trough and also interstitial …

An Examination Of Individuals' Self-Selections To Organizations, Sarah Chan

Psychology Dissertations - Archive

It has long been noted that people have a tendency to look for and engage in situations that are congruent with their personalities, their self-concepts, their interests, their attitudes and their values (Allport, 1937; Bandura, 1973; Ickes, Snyder & Garcia, 1997). However, most studies in the Person-Organization fit area are limited to examining employees who have been hired, while the self-selection process of choosing to apply for certain organizations or the self-assessment of fit with an organization are less explored. The present study examines job seekers' decision-making processes on ratings of attractiveness for hypothetical companies. Using a decision-making process model …

Synthesis And Characterization Of Magnetic Nanoparticles, Narayan Poudyal

Physics Theses - Archive

Synthesis of uniform nanoparticles (<100 nm) of hard and soft magnetic materials have attracted much attention in the last two decades because of their unique magnetic properties and potential for many applications such as high density recording media, biotechnology, ferrofluids, and fabrication of exchange-coupled nanocomposite permanent magnets. In this thesis, synthesis and characterization of hard (FePt) and soft (Fe3O4 and CoFe2O4) magnetic nanoparticles with different sizes are reported. Monodisperse FePt, Fe3O4 and CoFe2O4 nanoparticles were synthesized by chemical solution methods. Particle diameter was tuned from 3 to 20 nm by varying reaction conditions or by seed-mediated growth method. Monodisperse face-centered tetragonal (fct) FePt nanoparticles were prepared by annealing at 700oC the disodered face-centered cubic (fcc) FePt nanopaticles in NaCl matrix to convert the fcc particles into ordered fct structure. Morphological, structural, and compositional characterizations of the nanoparticles were performed by Transmission Electron Microscopy (TEM), High resolution TEM (HRTEM), Laser Particle-Size Analyzer, X-ray Diffractometer (XRD), Energy Dispersive X-ray (EDX), and Inductively Coupled Plasma (ICP). Magnetic properties of nanoparticles of different sizes at different temperatures were studied by Anternating Gradiant Magnetometer (AGM), and Superconducting Quantum Interference Device (SQUID) magnetometer. It has been found that all the as-synthesized Fe3O4 nanoparticles up to 20 nm are superparamagnetic at room temperatue while CoFe2O4 nanoparticles larger than 12 nm are ferromagnetic. An exchange bias field up to 3 kOe was observed for 3 nm CoFe2O4 nanoparticles in field cooling measurements. Very high coercivity of the isolated fct FePt nanoparticles up to 30 kOe at room temperature has been obtained. Interesting experimental results on the size dependent magnetic properties for both the hard and soft magnetic nanoparticles at different temperatures have been found.

A First-Principles Study On The Enhancement Of Beryllium Doping In Gallium Nitride, Xiao Wang

Physics Theses - Archive

The excellent physical and electrical properties of Gallium Nitride (GaN) have made it a good candidate in light-emitting diodes and UV detecting semiconductor materials. However, GaN's p-type doping has long been a difficulty. Although beryllium (Be) substitutials arise as shallow acceptors in GaN, the concentration of Be substitutials, and hence the population of holes, is not high enough. In the present work, formation energies of Be point defects and complex defects are calculated and compared by first-principles density functional theory (DFT) method. We find self-compensation is easily formed when Be substitutials and Be interstitials co-exist in GaN, which is responsible …

On The Behavior Of The 5f Electrons, Pratik Pankajkumar Dholabhai

Physics Theses - Archive

Considerable theoretical efforts have been devoted in recent years to studying the electronic and geometric structures and related properties of surfaces to high accuracy. One of the many motivations for this burgeoning effort has been a desire to understand the detailed mechanisms that lead to surface corrosion in the presence of environmental gases; a problem that is not only scientifically and technologically challenging but also environmentally important. Such efforts are particularly important for systems like the actinides for which experimental work is relatively difficult to perform due to material problems and toxicity. As is known, the actinides are characterized by …

Piezoelectric Analysis For Hetrogeneous Medium, Solmaz Torabi

Material Science and Engineering Theses - Archive

In the recent years, several types of piezocomposites have been fabricated since they have provided material properties superior to conventional piezoelectric materials. In order to design these composites, it is essential to find the elastic and electric fields for their different parts, as well as the effective properties of the composite. In the present study, the analytical approach based on the extension of Eshelby's theory in piezoelectricity and the numerical approach based on FEM modeling and ANSYS software have been used to find these elastic and electric fields inside the piezoceramic inhomogeneity for two different piezocomposite according to their connectivity, …

Nonlinear H2/H∞ Constrained Feedback Control: A Practical Design Approach Using Neural Networks, Murad Abu-Khalaf

Electrical Engineering Dissertations - Archive

In this research, practical methods for the design of H2 and H8 optimal state feedback controllers for constrained input systems are proposed. The dynamic programming principle is used along with special quasi-norms to derive the structure of both the saturated H2 and H8 optimal controllers in feedback strategy form. The resulting Hamilton-Jacobi-Bellman (HJB) and Hamilton-Jacobi-Isaacs (HJI) equations are derived respectively. It is shown that introducing quasi-norms on the constrained input in the performance functional allows unconstrained minimization of the Hamiltonian of the corresponding optimal control problem. Moreover, it is shown how to obtain nearly optimal minimum-time and constrained state controllers …

Finding Blood In Capsule Endoscopy Video, Jay Frederick Cox

Computer Science and Engineering Theses - Archive

Capsule Endoscopy (CE) is a new procedure where endoscopists can visualize and discriminate anomalies of the human gastrointestinal track by allowing the patient to swallow a camera pill. The digital video obtained from the pill is used to safely pinpoint the location of these abnormalities in areas previously unavailable for view. One of the main functions of CE is determining the location of bleeding. Given Imaging, currently the only maker of a FDA approved CE device, has a proprietary and unspecified blood test, called Suspected Blood Index, which can be used to automatically detect where blood occurs in the video. …