Engineering Commons^™

A Comparison Of Two Method For Dg Optimizing In Power System, Yu Li

Electronic Theses and Dissertations

In this paper, we mainly focus on using new method to solve the DG problem in order to reducing the loss. We start from comparing two new method. We list out the mathematics theory of the two methods. And then, we using a 33 bus modeling to show which method has a better function on reducing the loss for system. After that, we take the better method to reducing the loss for two cases (14 bus , 34 bus modeling). At last, we conclude the result of the research and give some comment on the future works.

Study Of Bidirectional Broadband Passive Optical Network (Bpon) Using Edfa, Yasser Almalaq

Electronic Theses and Dissertations

Optical line terminals (OLTs) and number of optical network units (ONUs) are two main parts of passive optical network (PON). OLT is placed at the central office of the service providers, the ONUs are located near to the end subscribers. When compared with point-to-point design, a PON decreases the number of fiber used and central office components required.

Broadband PON (BPON), which is one type of PON, can support high-speed voice, data and video services to subscribers' residential homes and small businesses. In this research, by using erbium doped fiber amplifier (EDFA), the performance of bi-directional BPON is experimented and …

2014 Tsu Undergraduate Research Program, David Owerbach

Office of Research Institutional Research and Scholarship

No abstract provided.

Thermal And Structural Modeling Of Electrochromics On Glass, Mahesh B. Manandhar

Electronic Theses and Dissertations

Advanced glazing is a type of window glazing that interacts with the surrounding environment to change its thermal and optical properties to create a more comfortable and energy efficient indoor environment. Electrochromics are one type of such advanced glazing materials that change their properties in response to an externally applied voltage controllable by the user or by automation.

The effectiveness of electrochromics depends upon how well it can keep off extreme temperature conditions from outdoors all year round as well as how structurally stable it can remain at such conditions. This research investigates the use of COMSOL, a finite element …

Design Of A Sign-Out Process To Improve Surgical Safety, Sumonthip Chompoodang Gmitro

All Theses

According to the World Health Organization (WHO), the surgical safety checklist consists of three parts; sign-in, time-out and sign-out. It has been observed that the sign-out process is the least frequently completed. In this study, because of a concern for the risk of adverse events occurring in the OR, the sign-out process used in a local hospital was redesigned as a web-based application embedded on a desktop computer and on a mobile device. Both web-based platforms were tested along with the current sign-out process on a computer. Eighteen circulating nurses in the operating rooms of Greenville Memorial Hospital used each …

Atomistic Simulation And Virtual Diffraction Characterization Of Alumina Interfaces: Evaluating Structure And Stability For Predictive Physical Vapor Deposition Models, Shawn Patrick Coleman

Graduate Theses and Dissertations

The objectives of this work are to investigate the structure and energetic stability of different alumina (Al₂O₃) phases using atomistic simulation and virtual diffraction characterization. To meet these objectives, this research performs molecular statics and molecular dynamics simulations employing the reactive force-field (ReaxFF) potential to model bulk, interface, and surface structures in the θ-, γ-, κ-, and α-Al₂O₃ system. Simulations throughout this study are characterized using a new virtual diffraction algorithm, developed and implemented for this work, that creates both selected area electron diffraction (SAED) and x-ray diffraction (XRD) line profiles without assuming …

Mitigation Of Alkali-Silica Reaction (Asr) In An Interstate Median Barrier, Richard Albert Deschenes

Graduate Theses and Dissertations

In 2012 it was discovered that roughly 4 miles of interstate median barrier along Interstate 540 had rapidly deteriorated. After the initial inspection, a sample was submitted for analysis, and found to contain evidence of alkali-silica reaction (ASR). A research program was implemented with the goal of determining the cause of ASR and developing a program for mitigating the ongoing deterioration. The median barrier had not deteriorated equally throughout the 4 miles, and the level of damage varied considerable throughout the length. A visual inspection of the median barrier was conducted and the median barrier was divided into sections based …

Durability Of Silane Sealer In A Highly Alkaline Environment, Cameron David Murray

Graduate Theses and Dissertations

Alkali-silica reaction (ASR) is a chemical reaction between siliceous minerals present in certain aggregates and alkalis in the concrete pore solution. The reaction can lead to expansion and severe damage in concrete members. One method to mitigate ASR expansion is to use a penetrating sealer such as silane. A set of columns located in a food preparation facility was treated with silane and a complimentary laboratory study was performed. A cleaning regimen involving application of an alkaline cleaner is employed at the facility, followed by rinsing with hot, pressurized water. The purpose of this research is to evaluate the effectiveness …

Dynamic Testing Of An Elevated Water Tank, Alexander Michael Font

Graduate Theses and Dissertations

The objective of this thesis was to identify the modal properties of a pedesphere type, elevated water tank under different operating conditions relating to the water level in the tank. The research that was conducted included both numerical and experimental components. The numerical components consisted of a simple hand calculation to identify the fundamental frequency as well as numerical computer models to identify the natural frequencies and mode shapes for the first three bending modes. The experimental components consisted of characterizing the vibration of the elevated water tank in its current environment through ambient vibration testing.

Multiple Reference Impact Testing Of Bridges Using A Network Of Low-Cost Dynamic Exciters, James David Lindsey

Graduate Theses and Dissertations

Multiple Reference Impact Testing (MRIT) is a form of Experimental Modal Analysis (EMA) that can be used to identify the dynamic properties of full-scale bridges. These dynamic properties include natural frequencies, mode shapes, damping ratios, modal scaling and modal flexibility. Since these system properties that are directly related to the mass and stiffness characteristics of a structure, impact test measurements can be used to quantitatively characterize condition of a structure. Over time, changes in the properties can be monitored and evaluated as indicators of damage or deterioration. Instrumented hammers and drop masses are typically used to perform MRIT by providing …

Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe

Graduate Theses and Dissertations

A compacted clay liner (test pad) was constructed and instrumented with volumetric water content and soil matric potential sensors to determine soil water characteristic curves (SWCC) and hydraulic conductivity (k) functions. Specifically, the compacted clay liner was subjected to an infiltration cycle during a sealed double ring infiltrometer (SDRI) test followed by a drying cycle. After the drying cycle, Shelby tube samples were collected from the compacted clay liner and flexible wall permeability (FWP) tests were conducted on sub-samples to determine the saturated hydraulic conductivity. Moreover, two computer programs (RETC and UNSAT-H) were utilized to model the SWCCs and k-functions …

Homotopy Techniques In Solving Systems Of Nonlinear Equations: A Theoretical Justification Of Convex Combinations, Nicholas Sun

Departmental Technical Reports (CS)

One of the techniques for solving systems of non-linear equations F₁(x₁,...,x_n) = 0, ..., F_n(x₁,...,x_n) = 0, (F(x) = 0 in vector notations) is a homotopy method, when we start with a solution of a simplified (and thus easier-to-solve) approximate system G_i(x₁,...,x_n) = 0, and then gradually adjust this solution by solving intermediate systems of equation H_i(x₁,...,x_n) = 0 for an appropriate "transition" function H(x) = f(λ,F(x),G(x)). The success of this method depends on the …

Log-Periodic Power Law As A Predictor Of Catastrophic Events: A New Mathematical Justification, Vladik Kreinovich, Hung T. Nguyen, Songsak Sriboonchitta

Departmental Technical Reports (CS)

To decrease the damage caused by meteorological disasters, it is important to be able to predict these disasters as accurately as possible. One of the most promising ways of achieving such a prediction comes from the observation that in the vicinity of a catastrophic event, many parameters exhibit log-periodic power behavior, with oscillations of increasing frequency. By fitting the corresponding formula to the observations, it is often possible to predict the catastrophic event. Such successful predictions were made in many application areas ranging from ruptures of fuel tanks to earthquakes to stock market disruptions. The fact that similar formulas can …

A Dual Band High Impedance Antenna For Rf Harvest Applications, Andres J. Medina

Theses and Dissertations - UTB/UTPA

A design for a compact dual band very high impedance antenna for RF Harvest applications is presented. The antenna is designed to present a very high input impedance at its feed point at 900 MHz and 1.8 GHz. The design incorporates the folding concept into a customized bowtie antenna to achieve high input impedance. The design methodology and simulations are presented, as well as a comparison of the measured results against the simulation results. A rectifier circuit and dual band matching network are also simulated and presented.

Commuter Rail, Timothy J. Brock, Reginald R. Souleyrette

Civil Engineering Faculty Publications

No abstract provided.

Evaluating The Effectiveness Of The Global Nuclear Detection Architecture Using Multiple-Objective Decision Analysis, Holly Hilliard

Industrial Engineering Undergraduate Honors Theses

The National Academy of Sciences has recently completed a study of the Global Nuclear Detection Architecture (GNDA) Metrics for the Department of Homeland Security's Domestic Nuclear Detection Office. This research uses the reports strategic framework and notional metrics (and additional information) to develop one overall measure of GNDA effectiveness. The potential benefit of one effectiveness measure would be ability to assess and communicate progress over time to the diverse group of national and international stakeholders and decision makers. This thesis uses the mathematics of multiple objective decision analysis to develop the effectiveness measure. A notional model was developed and it …

Numerical Investigation Of Hydrodynamic Focusing And Coulter Principle In A Microfluidic Device, Muheng Zhang

Electronic Theses and Dissertations

Particle information such as particle size and amount is significant to many fields such as chemical engineering, biological research, medical analysis, and environment detection. Microfluidic Coulter counter is suitable for this task because it can get fast and accurate analysis. However, the fundamental principle and several design strategies details are still needed to be analyzed and modeled in order to improve its performance. This dissertation focused on several challenges from the numerical simulation aspects. First one is the analysis for the hydrodynamic focusing in microfluidic Coulter Counter. In recent years, many microfluidic Coulter Counter designs have utilized a technique termed …

Utilizing Radiation For Smart Robotic Applications Using Visible, Thermal, And Polarization Images., Ali H. Mahmoud

Electronic Theses and Dissertations

The domain of this research is the use of computer vision methodologies in utilizing radiation for smart robotic applications for driving assistance. Radiation can be emitted by an object, reflected or transmitted. Understanding the nature and the properties of the radiation forming an image is essential in interpreting the information in that image which can then be used by a machine e.g. a smart vehicle to make a decision and perform an action. Throughout this work, different types of images are used to help a robotic vehicle make a decision and perform a certain action. This work presents three smart …

A Novel Nmf-Based Dwi Cad Framework For Prostate Cancer., Patrick Mcclure

Electronic Theses and Dissertations

In this thesis, a computer aided diagnostic (CAD) framework for detecting prostate cancer in DWI data is proposed. The proposed CAD method consists of two frameworks that use nonnegative matrix factorization (NMF) to learn meaningful features from sets of high-dimensional data. The first technique, is a three dimensional (3D) level-set DWI prostate segmentation algorithm guided by a novel probabilistic speed function. This speed function is driven by the features learned by NMF from 3D appearance, shape, and spatial data. The second technique, is a probabilistic classifier that seeks to label a prostate segmented from DWI data as either alignat, contain …

A Novel Diffusion Tensor Imaging-Based Computer-Aided Diagnostic System For Early Diagnosis Of Autism., Mahmoud Mostapha

Electronic Theses and Dissertations

Autism spectrum disorders (ASDs) denote a significant growing public health concern. Currently, one in 68 children has been diagnosed with ASDs in the United States, and most children are diagnosed after the age of four, despite the fact that ASDs can be identified as early as age two. The ultimate goal of this thesis is to develop a computer-aided diagnosis (CAD) system for the accurate and early diagnosis of ASDs using diffusion tensor imaging (DTI). This CAD system consists of three main steps. First, the brain tissues are segmented based on three image descriptors: a visual appearance model that has …

The Second Generation Of The Cccm System For In-Vitro Cardiac Tissue Engineering., Mai-Dung Thi Nguyen

Electronic Theses and Dissertations

Cardiovascular disease is the leading cause of death worldwide. When a myocardial infarction occurs, scar tissue compensates the damaged myocardial tissue. This scar tissue increases the stiffness of the heart tissue, reduces the heart’s function, and finally leads to the heart failure (HF) disease. To have the tissue engraftment, in-vitro cardiac tissue should have the same properties as the native mature cardiac tissue. However, current in-vitro cell culture technologies fail to accurately recreate the in-vivo like mechanically physiological environment for in-vitro cardiac tissue culture, and therefore, fail to regenerate the in-vivo like mature cardiac tissue. Hence, a microfluidic cardiac cell …

Semi-Blind Robust Indentification And Robust Control Approach To Personalized Anemia Management., Elom Akabua

Electronic Theses and Dissertations

The homeostatic blood hemoglobin (Hb) content of a healthy individual varies between the range of 14-18 g/dL for a male and 12-16 g/dL for a female. This quantity provides an estimate of red blood cell (RBC) count in circulation at any given moment. RBC is a protein carrying substance that transports oxygen from the lungs to other tissues in the body and is synthesized by the kidney through a process known as erythropoiesis where erythropoietin is secreted in response to hypoxia. In this regard, the kidneys act not only as a controller but also as a sensor in regulating RBC …

Fast And Robust Hybrid Framework For Infant Brain Classification From Structural Mri : A Case Study For Early Diagnosis Of Autism., Amir Alansary

Electronic Theses and Dissertations

The ultimate goal of this work is to develop a computer-aided diagnosis (CAD) system for early autism diagnosis from infant structural magnetic resonance imaging (MRI). The vital step to achieve this goal is to get accurate segmentation of the different brain structures: whitematter, graymatter, and cerebrospinal fluid, which will be the main focus of this thesis. The proposed brain classification approach consists of two major steps. First, the brain is extracted based on the integration of a stochastic model that serves to learn the visual appearance of the brain texture, and a geometric model that preserves the brain geometry during …

Photomechanical Actuation Of Liquid Crystal Nanotube Elastomers., Xiaoming Fan

Electronic Theses and Dissertations

Elastomeric composites based on nanotube liquid crystals (LCs) that preserve the internal orientation of nanotubes could lead to anisotropic physical properties and flexible energy conversion. Using simple vacuum filtration technique of fabricating nanotube LCs films and utilizing a transfer process to poly (dimethyl) siloxane wherein the LCs arrangement is preserved, in this thesis we demonstrate unique and reversible photomechanical response of this layered composite to excitation by near infra-red (NIR) light at ultra-low nanotube mass fractions. Schlieren textures were noted in these LCs composites confirming long range macroscopic nematic order of nanotubes within the composites. Maximum photomechanical stress of ~23kPa, …

Nanoporous Bi2te3 Thermoelectric Based Knudsen Gas Pump., Abderrazzak Faiz

Electronic Theses and Dissertations

This dissertation reports on the fabrication of a bi-directional Knudsen gas pump using a multifunctional nanoporous thermoelectric material. The integration of the channels into the thermoelectric material has the advantages of reducing heat losses and power consumption, improving the pump efficiency, and reducing the overall pump size. The Knudsen pump operates on the thermal transpiration principle, the phenomenon that gas molecules drift from the cold end to the hot end of a narrow channel. The gas pumping is realized in the transition or free molecular regime. The Knudsen pump is needed in a great number of applications such as gas …

Hydraulic Switch For Dishwashers With Bottle Blaster System., Lazaro Galban

Electronic Theses and Dissertations

A dishwasher works by using water pressure to operate the Spray Arms. There are different types of wash systems with the most common being two spray arms, a lower and middle arm. These two spray arms operate independently from each other and can be powered individually. In this particular wash system, the subsystem of interest is the Mid Spray Arm which is connected with the Bottle Blaster where both operate simultaneously. The Mid Spray Arm is used to clean the upper dishwasher rack while the Bottle Blaster is used to clean bottles, also in the upper rack. In order to …

Numerical Study Of Leading Edge Vortex Circulation Development On Finite Aspect Ratio Perching Wings., Kyle Hord

Electronic Theses and Dissertations

The perching maneuver of natural fliers is a complex motion involving fast change of angle of attack, complicated wing kinematics, large wing deformation and agile body motion control, but the prominent aerodynamic features can be revealed using a simple pitch-up wing motion coupled with a stream wise deceleration. In this dissertation the aerodynamic forces, the leading edge vorterx (LEV) development, and LEV circulation of pitch-up and perching wings are extensively studied at low Reynolds number conditions. 2D and 3D wings of different aspect ratios were linearly pitched up from 0 to 90 at three reduced pitch rates. The numerical investigation …

Context Dependent Spectral Unmixing., Hamdi Jenzri

Electronic Theses and Dissertations

A hyperspectral unmixing algorithm that finds multiple sets of endmembers is proposed. The algorithm, called Context Dependent Spectral Unmixing (CDSU), is a local approach that adapts the unmixing to different regions of the spectral space. It is based on a novel function that combines context identification and unmixing. This joint objective function models contexts as compact clusters and uses the linear mixing model as the basis for unmixing. Several variations of the CDSU, that provide additional desirable features, are also proposed. First, the Context Dependent Spectral unmixing using the Mahalanobis Distance (CDSUM) offers the advantage of identifying non-spherical clusters in …

Analysis Of Contrast-Enhanced Medical Images., Fahmi Abdallah Fahmi Mohammed Khalifa

Electronic Theses and Dissertations

Early detection of human organ diseases is of great importance for the accurate diagnosis and institution of appropriate therapies. This can potentially prevent progression to end-stage disease by detecting precursors that evaluate organ functionality. In addition, it also assists the clinicians for therapy evaluation, tracking diseases progression, and surgery operations. Advances in functional and contrast-enhanced (CE) medical images enabled accurate noninvasive evaluation of organ functionality due to their ability to provide superior anatomical and functional information about the tissue-of-interest. The main objective of this dissertation is to develop a computer-aided diagnostic (CAD) system for analyzing complex data from CE magnetic …

Investigation Of Stabilization Mechanisms For Colloidal Suspension Using Nanoparticles., Qingwen He

Electronic Theses and Dissertations

Over the past decade, charged nanoparticles have been found to enhance the stability of colloidal suspensions. One promising explanation of this stabilization mechanism is “Nanoparticle Haloing”- the formation of a non-adsorbing nanoparticle layer surrounding neutral colloids that would induce an effective electrostatic repulsion between them. The objective of this work was to investigate the effect of additional charged nanoparticles on the interaction between neural colloids in nanoparticle-regulated complex fluids. Firstly, colloidal probe Atomic Force Microscopy (CP-AFM) is used to directly measure the interaction force in such system with nanoparticle volume fractions varying from 10-6 to 10-2. It is found that …