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Electronic Theses and Dissertations

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Full-Text Articles in Engineering

Operational Decision Making For Medical Clinics Through The Use Of Simulation And Multi-Attribute Utility Theory., Bo Sun May 2016

Operational Decision Making For Medical Clinics Through The Use Of Simulation And Multi-Attribute Utility Theory., Bo Sun

Electronic Theses and Dissertations

Currently, health care is a large industry that concerns everyone. Outpatient health care is an important part of the American health care system and is one of the strongest growth areas in the health care system. Many people pay attention to how to keep basic health care available to as many people as possible. A large health care system is usually evaluated by many performance measures. For example, the managers of a medical clinic are concerned about increasing staff utilization; both managers and patients are concerned about patient waiting time. In this dissertation, we study decision making for clinics in …


Mixing And Mean Age In Multiphase Systems., David Chandler Russ May 2016

Mixing And Mean Age In Multiphase Systems., David Chandler Russ

Electronic Theses and Dissertations

Mean age theory is a useful tool for analyzing mixing by providing spatial distributions of time based data for material inside a system using a steady-state CFD approach, but has been limited to single phase systems. Mean age theory was extended here to multiphase systems by defining the scalar tracer concentration independently for individual phases, which allows mean age to be solved at steady-state for each phase independently within a multiphase system. The theory was validated by comparing multiphase mean age (MMA) distributions extracted from spatial distributions determined computationally at two locations where RTDs were experimentally measured in a water-oil …


A Preliminary Study Of The Relationship Between Complexity, Motivation, And Design Quality., Philip John Mountain Apr 2016

A Preliminary Study Of The Relationship Between Complexity, Motivation, And Design Quality., Philip John Mountain

Electronic Theses and Dissertations

This collection of work comprises a preliminary study of the relationships between product complexity, design motivation, and design quality. Complexity, as it relates to the design process, is largely undefined and there exists no generally accepted method of measurement. This study applies an independent data set to a complexity measurement technique and develops complexity measurements at the pre and post design stages. Pre design is considered when design ideas are in formation and customer needs are being addressed. Post design is considered when a functional prototype is realized, manufacturing and assembly processes have been considered, and the product design is …


Foot Strike Patterns And Body Alignment Effects On Muscle Activity During Running., Nicole Knapp Mar 2016

Foot Strike Patterns And Body Alignment Effects On Muscle Activity During Running., Nicole Knapp

Electronic Theses and Dissertations

The mechanics of the running stride was altered around the 1970s when shoes were released with an elevated heel (McDougall 2009). At this point in time a heel strike running style became increasingly common and has remained the popular pattern when running in traditional shoes. In fact, the exact same person has been seen to alter their stride when running in a traditional shoe where they heel strike verses barefoot where they take on a forefoot strike (Lieberman 2010).

When an individual heel strikes, the ground reaction force is greater and contains an initial peak which is void in a …


Synthesis And Characterization Of Kesterite Cu2znsns4 (Czts) Thin Films For Solar Cell Application, Mohamed M.A. Abusnina Jan 2016

Synthesis And Characterization Of Kesterite Cu2znsns4 (Czts) Thin Films For Solar Cell Application, Mohamed M.A. Abusnina

Electronic Theses and Dissertations

The quaternary compound Cu2ZnSnS4 (CZTS) gained considerable attention in the last decade due to its potential as an active-layer semiconductor for low-cost thin-film solar cells. The material is composed of nontoxic and Earth-abundant constituents, has optical properties suitable for photovoltaic application, and can be synthesized using a wide variety of methods.

Polycrystalline CZTS was grown in this work using vacuum-based deposition to first deposit metal films (precursors) of Cu, Zn, and Sn. In a subsequent step, the precursors underwent an annealing treatment in sulfur vapor environment (sulfurization) to form CZTS. Using sputtering, a physical vapor deposition (PVD) …


Cost-Effective Prosthetic Hand Controlled By Emg, Mohammad Yahya Almuhanna Jan 2016

Cost-Effective Prosthetic Hand Controlled By Emg, Mohammad Yahya Almuhanna

Electronic Theses and Dissertations

A cost-effective five-finger prosthetic hand is designed from aluminum, modeled and controlled using surface Electromyography (EMG) signals, which are obtained from the human body. Force sensors are used to control required forces needed to grasp and pick objects. A prototype hand is developed and it is experimentally tested to reproduce a wide spectrum of human hand motions. The size of the five-finger hand is similar to an adult male human hand, and it is capable of reproducing most of movements. Each finger has the same number of links as the real/human hand. Each finger also has a force sensor used …


Integrated Phev Charging Loads Forecasting Model And Optimization Strategies, Yin Yao Jan 2016

Integrated Phev Charging Loads Forecasting Model And Optimization Strategies, Yin Yao

Electronic Theses and Dissertations

In this dissertation, an integrated Plug-in Electric Vehicle (PHEV) charging loads forecasting model is developed for regular distribution level system and microgrid system. For regular distribution system, charging schedule optimization is followed up. The objectives are 1. Better cooperation with renewable energy sources (especially wind). 2. Relieving the pressure of current distribution transformers in condition of high penetration level PHEVs. As for microgrid, renewable energy power plants (wind, solar) plays a more important role than regular system. Due to the fluctuation of solar and wind plants' output, an empirical probabilistic model is developed to predict their hourly output. On the …


A Reserve-Based Method For Mitigating The Impact Of Renewable Energy, Ibrahim Krad Jan 2016

A Reserve-Based Method For Mitigating The Impact Of Renewable Energy, Ibrahim Krad

Electronic Theses and Dissertations

The fundamental operating paradigm of today's power systems is undergoing a significant shift. This is partially motivated by the increased desire for incorporating variable renewable energy resources into generation portfolios. While these generating technologies offer clean energy at zero marginal cost, i.e. no fuel costs, they also offer unique operating challenges for system operators. Perhaps the biggest operating challenge these resources introduce is accommodating their intermittent fuel source availability. For this reason, these generators increase the system-wide variability and uncertainty. As a result, system operators are revisiting traditional operating strategies to more efficiently incorporate these generation resources to maximize the …


Modeling And Simulation Of Optical Properties Of Noble Metals Triangular Nanoprisms, Soad Zahir Alsheheri Jan 2016

Modeling And Simulation Of Optical Properties Of Noble Metals Triangular Nanoprisms, Soad Zahir Alsheheri

Electronic Theses and Dissertations

Gold and silver has gained huge attention across the scientific community for its applications arising from its plasmonic properties. The optical properties achieved by these materials via excitation of plasmons is very unique to these materials and used as diagnostic and therapeutic agents in the field of medicine, and as sensors in a gamut of disciplines such as energy and environmental protection to name a few. Surface plasmon resonance (SPR) properties of the gold and silver are size and shape dependent. Of the various shapes reported in literature, triangular nanoprisms has tunable optical properties in the visible and near IR …


Autonomous Collision Avoidance For A Teleoperated Uav Based On A Super-Ellipsoidal Potential Function, Mohammed Salim Qasim Jan 2016

Autonomous Collision Avoidance For A Teleoperated Uav Based On A Super-Ellipsoidal Potential Function, Mohammed Salim Qasim

Electronic Theses and Dissertations

This thesis presents the design of a super-ellipsoidal potential function (SEPF) that can be used, in a static and dynamic environment, for autonomous collision avoidance of an unmanned aerial vehicle (UAV) in a 3-dimensional space. In the design of the SEPF, we have the full control over the shape and size of the potential function. In our proposed approach, a teleoperated UAV can not only autonomously avoid collision with surrounding objects but also track the operator' control input as closely as possible. As a result, an operator can always be in control of the UAV for his/her high-level guidance and …


Ex-Vivo Slaughterhouse Porcine Crystalloid-Perfused Beating Heart Via Langendorff Method, Rahiemin Talukder Jan 2016

Ex-Vivo Slaughterhouse Porcine Crystalloid-Perfused Beating Heart Via Langendorff Method, Rahiemin Talukder

Electronic Theses and Dissertations

The objective of this study was to resuscitate isolated beating porcine hearts obtained from slaughterhouse swine for a minimum of 1 hour with a crystalloid buffer reperfusion instead of blood via an extracorporeal Langendorff apparatus. The isolated beating heart functions outside of the body under simulated physiologic conditions. Live functional anatomy was controlled under benchtop experimental settings. Porcine hearts (26 total) were topically cooled with saline. 300mL of 25°C cardioplegia with 20KU Streptokinase was preflushed via aortic root. WIT was less than 5 minutes. 1L 4°C cardioplegia was flushed antegrade with aortic cannula (Group 1) or coronary catheterization (Group 2). …


Aging Assessment Of High Voltage Single Component Room Temperature Vulcanized Silicone Rubber (Rtv-1) Subjected To Aqueous Salt, Monika Bleszynski Jan 2016

Aging Assessment Of High Voltage Single Component Room Temperature Vulcanized Silicone Rubber (Rtv-1) Subjected To Aqueous Salt, Monika Bleszynski

Electronic Theses and Dissertations

Single component room temperature vulcanized (RTV-1) silicone based caulk used in high voltage insulators and other applications is frequently subjected to environmental pollutants. Aging of RTV-1 silicone rubber is the result of various stressors, including environmental aging conditions such as UV, acid, and salt exposure from ocean mist. Loss of hydrophobicity due to damage of the hydrophobic methyl groups, as well as loss of mechanical strength due to depolymerization via hydrolysis as a result of aqueous salt exposure were the two main factors of material aging assessed in this work. Multiple RTV-1 formulations were initially assessed for resistance to aging …


A Comprehensive Methodology For Design Of A Circulation Control Small-Scale Unmanned Aircraft, Konstantinos Kanistras Jan 2016

A Comprehensive Methodology For Design Of A Circulation Control Small-Scale Unmanned Aircraft, Konstantinos Kanistras

Electronic Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) have become increasingly prevalent and important for a wide spectrum of civilian and military operations. When focusing on small-scale fixed-wing UAVs, payload, power and energy requirements limit considerably their utilization and flexibility allowing them to complete only those specific missions they are designed for. Circulation Control (CC) is an active flow control method used to produce increased lift over the traditional systems (flaps, slats, etc...) currently in use. This dissertation focuses on the foundations of a comprehensive methodology from design to implementation and experimental testing of Coanda-based Circulation Control Wings (CCW) for unmanned aircraft. The …


Galvanic Corrosion Of Aluminum/Carbon Composite Systems, Eva Håkansson Jan 2016

Galvanic Corrosion Of Aluminum/Carbon Composite Systems, Eva Håkansson

Electronic Theses and Dissertations

Aluminum/carbon composite systems can have outstanding mechanical properties. Aluminum and carbon fiber reinforced polymer matrix composites (CFRP) are typically considered corrosion resistant when used alone, but can develop severe galvanic corrosion when in physical contact in the same component or structure.

General engineering practice is to avoid contact between aluminum and CFRP in any application where moisture may be present, but it is still of great importance to understand the consequences if the two materials accidentally become in contact. There may also be applications where a low rate of galvanic corrosion is acceptable.

This dissertation contributes unique experimental and numerical …


Design And Development Of The Ebear: A Socially Assistive Robot For Elderly People With Depression, Amirhossein Kargarbideh Jan 2016

Design And Development Of The Ebear: A Socially Assistive Robot For Elderly People With Depression, Amirhossein Kargarbideh

Electronic Theses and Dissertations

There has been tremendous progress in the field of robotics in the past decade and especially developing humanoid robots with social abilities that can assist human at a socio-emotional level. The objective of this thesis is to develop and study a perceptive and expressive animal-like robot equipped with artificial intelligence in assisting the elderly people with depression. We investigated how social robots can become companions of elderly individuals with depression and improve their mood and increase their happiness and well-being. The robotic platform built in this thesis is a bear-like robot called the eBear. The eBear can show facial expression …


Design And Development Of An Air Supply System For An Unmanned Circulation Control Aerial Vehicle, Pranith Chander Saka Jan 2016

Design And Development Of An Air Supply System For An Unmanned Circulation Control Aerial Vehicle, Pranith Chander Saka

Electronic Theses and Dissertations

Small-scale Unmanned Aerial Vehicles (UAVs) have been used for decades and are increasing in number and effectiveness as aircraft, sensor and automation technologies mature. Since the demand for UAV platforms capable of performing multiple missions with enhanced performance is increasing, technologies as Circulation Control (CC), which is an active flow control technique that is used to achieve enhanced payload and aerodynamic efficiency, attracts the interest of the research community. This thesis describes the design, development,integration and testing (ground and flight testing) of a CC system capable to provide the required mass flow for a CC-based flight. Performance evaluation is conducted …


Ultra-Wideband Radar Based Human Motion Analysis, Zhichong Zhou Jan 2016

Ultra-Wideband Radar Based Human Motion Analysis, Zhichong Zhou

Electronic Theses and Dissertations

This thesis proposes and investigates two techniques in ultra-wideband (UWB) radar based human motion analysis. The first one is accurate human body landmark detection using UWB radars. The detection is achieved by moving target indication (MTI) and constant false alarm rate detection (CFAR). A new CFAR detection technique is proposed, namely the out-of-band (OB) CFAR detection. In the field experiment, two RF reflective markers are attached to the wrist and elbow of one human arm for reflecting radar signals. It is demonstrated that detection of two markers are feasible and successfully achieved. And our results suggests the OB-CFAR performs better …


Design And Control Of Islanded Microgrid, Zeya Cai Jan 2016

Design And Control Of Islanded Microgrid, Zeya Cai

Electronic Theses and Dissertations

The control of frequency and power has always been a problem in the development of microgrid. This thesis focuses on the design and control of islanded microgrid; more specifically, it includes the design of the PV system and wind power system and the control of the frequency, voltage and the power output of the islanded microgrid.

Microgrid consists of the power sources, the control system, the distribution network and the load. More specifically, the power sources are composed of PV system and wind turbine system; the control system in the microgrid includes the droop controller, the Maximum Power Point Tracking …


Power Grid Management In Response To Extreme Events, Rozhin Eskandarpour Jan 2016

Power Grid Management In Response To Extreme Events, Rozhin Eskandarpour

Electronic Theses and Dissertations

Power system management in response to extreme events is one the most important operational aspects of power systems. In this thesis, a novel Event-driven Security Constrained Unit Commitment (E-SCUC) model and a statistical method, based on regression and data mining to estimate the system components outages, are proposed. The proposed models help consider the simultaneous outage of several system components represented by an N-1-m reliability criterion and accordingly determine the proper system response. In addition, an optimal microgrid placement model with the objective of minimizing the cost of unserved energy to enhance power system resilience is proposed.

The …


Bioremediation Of A Trichloroethene Dnapl Source Zone Utilizing A Partitioning Electron Donor - Field Implementation, Joseph Bartlett Jan 2016

Bioremediation Of A Trichloroethene Dnapl Source Zone Utilizing A Partitioning Electron Donor - Field Implementation, Joseph Bartlett

Electronic Theses and Dissertations

Trichloroethene (TCE) is a chlorinated volatile organic compound (CVOC) that can be found in industrial and household products. It is typically used as a solvent or degreaser. TCE can have detrimental health impacts and is known to be carcinogenic to humans. Federal and state regulatory drivers determine the need to assess and remediate soil and groundwater contaminated with CVOCs. There are many different methods for remediation; however, bioremediation has the ability to breakdown TCE all the way to harmless gasses (ethene and ethane). Bioremediation requires dechlorinating microbes (indigenous or augmented), electron donor (food source), and an electron acceptor (CVOCs). Electron …


A Simulation-Based Evaluation Of Efficiency Strategies For A Primary Care Clinic With Unscheduled Visits, Afrifah Bobbie Jan 2016

A Simulation-Based Evaluation Of Efficiency Strategies For A Primary Care Clinic With Unscheduled Visits, Afrifah Bobbie

Electronic Theses and Dissertations

In the health care industry, there are strategies to remove inefficiencies from the health delivery process called efficiency strategies. This dissertation proposed a simulation model to evaluate the impact of the efficiency strategies on a primary care clinic with unscheduled "walk-in" patient visits. The simulation model captures the complex characteristics of the Orlando Veteran's Affairs Medical Center (VAMC) primary care clinic. This clinic system includes different types of patients, patient paths, and multiple resources that serve them. Added to the problem complexity is the presence of patient no-shows characteristics and unscheduled patient arrivals, a problem which has been until recently, …


Understanding Hydroclimatic Controls On Stream Network Dynamics Using Lidar Data, Seoyoung Kim Jan 2016

Understanding Hydroclimatic Controls On Stream Network Dynamics Using Lidar Data, Seoyoung Kim

Electronic Theses and Dissertations

This dissertation investigates the hydroclimatic controls on drainage network dynamics and characterizes the variation of drainage density in various climate regions. The methods were developed to extract the valley and wet channel networks based on Light Detection and Ranging (LiDAR) data including the elevation and intensity of laser returns. The study watersheds were selected based on the availability of streamflow observations and LiDAR data. Climate aridity index was used as a quantitative indicator for climate. The climate controls on drainage density were re-visited using watersheds with minimal anthropogenic interferences and compared with the U-shape relationship reported in the previous studies. …


A Systems Approach To Assessing, Interpreting And Applying Human Error Mishap Data To Mitigate Risk Of Future Incidents In A Space Exploration Ground Processing Operations Environment, Tiffaney Alexander Jan 2016

A Systems Approach To Assessing, Interpreting And Applying Human Error Mishap Data To Mitigate Risk Of Future Incidents In A Space Exploration Ground Processing Operations Environment, Tiffaney Alexander

Electronic Theses and Dissertations

Research results have shown that more than half of aviation, aerospace and aeronautics mishaps/incidents are attributed to human error. Although many existing incident report systems have been beneficial for identifying engineering failures, most of them are not designed around a theoretical framework of human error, thus failing to address core issues and causes of the mishaps. Therefore, it is imperative to develop a human error assessment framework to identify these causes. This research focused on identifying causes of human error and leading contributors to historical Launch Vehicle Ground Processing Operations mishaps based on past mishaps, near mishaps, and close calls. …


Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby Jan 2016

Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby

Electronic Theses and Dissertations

Fog along roadways is a dangerous hazard that leads to crashes resulting from limited visibility. Low visibility gives drivers less time to react to potential obstacles that can suddenly appear and require immediate action. To solve this issue, early warning systems involving Dynamic Message Signs or other types of devices are used to alert drivers of the impending visibility condition so that they are prepared. This research focuses on testing the effectiveness of one form of warning systems to investigate how it impacts driver behavior in foggy conditions. To accomplish this objective, a simulation study is developed to test variables …


Energy-Aware Reconfigurable Logic Device Using Spin-Based Storage And Carbon Nanotube Switching, Mohan Krishna Gopi Krishna Jan 2016

Energy-Aware Reconfigurable Logic Device Using Spin-Based Storage And Carbon Nanotube Switching, Mohan Krishna Gopi Krishna

Electronic Theses and Dissertations

Scaling of semiconductors to the 14-nanometer range and below nanometer range introduces serious design challenges that include high static power in memories and high leakage power, hindering further integration of CMOS devices. Thus, emerging devices are under intense analysis to overcome these drawbacks caused by transistor size scaling. Spintronics technology provides excellent features such as Non-Volatility, low read power, low read delay, higher scalability as well as easy integration with CMOS in comparison with SRAM memories. In addition, Carbon-Nanotube Field-Effect Transistors (CNFETs) provide superior electrical conductivity, low delay and low power consumption in comparison with conventional CMOS technology. Thus in …


On-Orbit Inter-Satellite Radiometric Calibration Of Cross-Track Scanning Microwave Radiometers, Hamideh Ebrahimi Jan 2016

On-Orbit Inter-Satellite Radiometric Calibration Of Cross-Track Scanning Microwave Radiometers, Hamideh Ebrahimi

Electronic Theses and Dissertations

This dissertation concerns the development of an improved algorithm for the inter-satellite radiometric calibration (XCAL) for cross track scanning microwave radiometers in support of NASA's Global Precipitation Mission (GPM). This research extends previous XCAL work to assess the robustness of the CFRSL "double difference" technique for sounder X-CAL. In this work, using a two-year of observations, we present a statistical analysis of radiometric biases performed over time and viewing geometry. In theory, it is possible to apply the same X-CAL procedure developed for conical-scanning radiometers to cross-track scanners; however the implementation is generally more tedious. For example, with the cross-track …


Control Of Metal-Release And Tuberculation In A Silica-Laden Groundwater Distribution System On The Volcanic Island Of Lana'i, Samantha Myers Jan 2016

Control Of Metal-Release And Tuberculation In A Silica-Laden Groundwater Distribution System On The Volcanic Island Of Lana'i, Samantha Myers

Electronic Theses and Dissertations

A corrosion control study for two distinct water distribution systems (WDS) has been completed for the Pulama Lana'i Water Company (Pulama). This project evaluated the use of chemical inhibitors to control corrosion and tuberculation within the Manele Bay WDS and the Lana'i City WDS. Pulama provides water to a population of 3,100 residents and is considering incorporating alternative water supplies in the future. Hence, knowing baseline corrosion rates within the WDS was desired. Several groundwater wells feed each of the WDS's; however, water quality between wells varies. Well water supplied to the WDS's is generally of high quality, therefore, the …


Joint Modeling Of Traffic Related Crashes: A Copula Based Approch, Tammam Nashad Jan 2016

Joint Modeling Of Traffic Related Crashes: A Copula Based Approch, Tammam Nashad

Electronic Theses and Dissertations

The study contributes to safety literature on transportation safety by employing copula based models for count frequency analysis at a macro-level. Most studies in the transportation safety area identify a single count variable (such as vehicular, pedestrian or bicycle crash counts) for a spatial unit and study the impact of exogenous variables. While the traditional count models perform adequately in the presence of a single count variable, it is necessary to modify these approaches to examine multiple dependent variables for each study unit. To that extent, the current research effort contributes to literature by developing two multivariate models based on …


Smart Grasping Using Laser And Tactile Array Sensors For Ucf-Manus- An Intelligent Assistive Robotic Manipulator, Kiran Prakash Jan 2016

Smart Grasping Using Laser And Tactile Array Sensors For Ucf-Manus- An Intelligent Assistive Robotic Manipulator, Kiran Prakash

Electronic Theses and Dissertations

This thesis presents three improvements in the UCF MANUS Assistive Robotic Manipulator's grasping abilities. Firstly, the robot can now grasp objects that are deformable, heavy and have uneven contact surfaces without undergoing slippage during robotic operations, e.g. paper cup, filled water bottle. This is achieved by installing a high precision non-contacting Laser sensor1 that runs with an algorithm that processes raw-input data from the sensor, registers smallest variation in the relative position of the object with respect to the gripper. Secondly, the robot can grasp objects that are as light and small as single cereal grain without deforming it. To …


Passive, Wireless Saw Ofc Strain Sensor And Software Defined Radio Interrogator, James Humphries Jan 2016

Passive, Wireless Saw Ofc Strain Sensor And Software Defined Radio Interrogator, James Humphries

Electronic Theses and Dissertations

Surface acoustic wave (SAW) devices have exhibited unique capabilities to meet the demands for many applications due to the inherent properties of SAW devices and piezoelectric materials. In particular, SAW devices have been adapted as sensors that can be configured to operate both passively and wirelessly. SAW sensors can be operated in harsh environmental extremes where typical sensor technologies are not able to operate. Because the sensors are passive, a radio transceiver is required to interrogate the sensor and receive the reflected response that has been modulated by the SAW device. This dissertation presents the design of a passive, wireless …