Engineering Commons^™

Enhancing Gan Led Efficiency Through Nano-Gratings And Standing Wave Analysis, Gabriel M. Halpin

Master's Theses

Improving energy efficient lighting is a necessary step in reducing energy consumption.Lighting currently consumes 17% of all U.S. residential and commercial electricity, but a report from the U.S. Office of Energy Efficiency and Renewable Energy projects that switching to LED lighting over the next 20 years will save 46% of electricity used in lighting.GaN LEDs are used for their efficient conversion of electricity to light, but improving GaN efficiency requires optically engineering the chip to extract more light.Total internal reflection limits GaN LED performance since light must approach the chip surface within 23.6° of normal to escape into air.This thesis …

An Algorithm To Recognize Multi-Stable Behavior From An Ensemble Of Stochastic Simulation Runs, Eduardo Monzon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic biological designers are demanding tools to help with the design and verification process of new biological models. Some of the most common tools available aggregate multiple simulation results into one “clean” trajectory that hopefully is representative of the system’s behavior. However, for systems exhibiting multiple stable states, these techniques fail to show all the possible trajectories of the system. This work introduces a method capable of detecting the presence of more than one “typical” trajectory in a system, which can also be integrated with other available simulation tools.

Developing A Framework For Determining The Contribution Of Transportation Project To Sustainable Development, Karim Ahmed Abdel Warith

Open Access Dissertations

In the past few years, stakeholders in the transportation industry have been concerned with sustainability. However, transportation decision makers have had difficulty incorporating sustainability into transportation infrastructure decisions. This is mainly attributed to the vagueness of the term. Incorporating sustainability into transportation decision making has been a desire put forth by engineers for that past 10 years. However, with no apparent method of defining sustainability, designers and decision makers have not been able to fulfill this desire.

This investigation attempts to define sustainability in a comprehensive and quantitative manner. The research proposes a new methodology that relies on the objective …

Real-Time Visualization Of Finite Element Models Using Surrogate Modeling Methods, Ryan C. Heap

Theses and Dissertations

Finite element analysis (FEA) software is used to obtain linear and non-linear solutions to one, two, and three-dimensional (3-D) geometric problems that will see a particular load and constraint case when put into service. Parametric FEA models are commonly used in iterative design processes in order to obtain an optimum model given a set of loads, constraints, objectives, and design parameters to vary. In some instances it is desirable for a designer to obtain some intuition about how changes in design parameters can affect the FEA solution of interest, before simply sending the model through the optimization loop. This could …

Using Real-Time Location Systems & Simulation Modeling To Improve Healthcare, Colby Thomas Mattie

Masters Theses

In the healthcare industry, facility managers often find themselves with limited resources, lack of timely data, and unexpected crises that they have to respond too. Their options are based on hastily made assumptions and a limited understanding of all implications of the problems at hand. This scenario has become a concerning issue for the healthcare industry where problems can arise at any time and every minute counts. The healthcare industry is also littered with wasteful processes and regulations that increase the cost for physicians and facility operators and decrease the overall care for the patients. This is very evident in …

The Effects Of Mismatches And Probe Tethering Configurations On The Stability Of Dna Duplexes On Surfaces, Kyle Evan Pratt

Theses and Dissertations

DNA microarrays are chip-based, analysis tools which can perform hundreds of thousands of parallel assays to determine the identity of genes or gene expression levels present in a sample. They have been identified as a key technology in genomic sciences and emergent medical techniques; however, despite their abundant use in research laboratories, microarrays have not been used in the clinical setting to the fullest potential due to the difficulty of obtaining reproducible results. Microarrays work on the principle of DNA hybridization, and can only be as accurate as this process is robust. Fundamental, molecular-level understanding of hybridization on surfaces is …

Using Discrete Event Simulation To Improve The Patient Care Process In The Emergency Department Of A Rural Kentucky Hospital., Molly Cassaro Jones

Electronic Theses and Dissertations

The patient care process of a rural Kentucky hospital is a complex process that must be flexible in order to deal with a large variety of patient needs and a fluctuating patient volume where all patients are unscheduled. A simulation model of an average month in the emergency department was built using the Arena Simulation package. Methods for creating a simulation using Arena are included in this work. Statistics were generated from a number of different sources to create an accurate representation of the model. The Hospital reporting shows a need to improve on two quality measures being tracked, the …

Uav Formation Flight Utilizing A Low Cost, Open Source Configuration, Christian W. Lopez

Master's Theses

The control of multiple unmanned aerial vehicles (UAVs) in a swarm or cooperative team scenario has been a topic of great interest for well over a decade, growing steadily with the advancements in UAV technologies. In the academic community, a majority of the studies conducted rely on simulation to test developed control strategies, with only a few institutions known to have nurtured the infrastructure required to propel multiple UAV control studies beyond simulation and into experimental testing. With the Cal Poly UAV FLOC Project, such an infrastructure was created, paving the way for future experimentation with multiple UAV control systems. …

East Tennessee Children's Hospital Lean, Eddie D. Eatherly, Catherine Julson, Kelsey Tjader, Jack Smodic, Lanier Loftin

Chancellor’s Honors Program Projects

No abstract provided.

Thermo-Piezo-Electro-Mechanical Simulation Of Algan (Aluminum Gallium Nitride) / Gan (Gallium Nitride) High Electron Mobility Transistor, Lorin E. Stevens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to the current public demand of faster, more powerful, and more reliable electronic devices, research is prolific these days in the area of high electron mobility transistor (HEMT) devices. This is because of their usefulness in RF (radio frequency) and microwave power amplifier applications including microwave vacuum tubes, cellular and personal communications services, and widespread broadband access. Although electrical transistor research has been ongoing since its inception in 1947, the transistor itself continues to evolve and improve much in part because of the many driven researchers and scientists throughout the world who are pushing the limits of what modern …

Traffic Modeling In Lagrangian Coordinates Using Smartphone Apps, Sergio Contreras

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traditionally, one of the ways traffic flow has been studied is by using the kinematic wave model. This model is derived in the Eulerian framework by using conservation of the number of vehicles. Recently, the kinematic wave model has been transformed into Lagrangian coordinates. In this framework, the independent variables are unique

vehicles and time. The detailed change in framework, and the properties of the model in the changed framework are reviewed. Numerical results from different traffic cases are explained. Since vehicle trajectory data can be easily collected from smartphones,

a smartphone application is developed for this purpose. This data …

Development Of Cfd Models For The Purposes Of Exploring Free Surface Wave Phenomena, Leonard P. Stoehr

Masters Theses

With the push for finding alternative, green energy sources, the harnessing of energy from ocean and lake waves is becoming a more researched field. To fully understand the behavior of wave interactions and optimize designs to extract this energy, it is necessary to develop computer models that can accurately replicate this behavior. A case is presented in which previous work done using the wave tank found in the Western Michigan University fluids lab is examined. The case involves harnessing the energy generated by ocean waves through the usage of plates of different shapes resting horizontally on the water’s surface. The …

Stochastic Modeling And Time-To-Event Analysis Of Voip Traffic, Imad Al Ajarmeh

College of Computing and Digital Media Dissertations

Voice over IP (VoIP) systems are gaining increased popularity due to the cost effectiveness, ease of management, and enhanced features and capabilities. Both enterprises and carriers are deploying VoIP systems to replace their TDM-based legacy voice networks. However, the lack of engineering models for VoIP systems has been realized by many researchers, especially for large-scale networks. The purpose of traffic engineering is to minimize call blocking probability and maximize resource utilization. The current traffic engineering models are inherited from the legacy PSTN world, and these models fall short from capturing the characteristics of new traffic patterns. The objective of this …

Protein-Surface Interactions With Coarse-Grain Simulation Methods, Shuai Wei

Theses and Dissertations

The interaction of proteins with surfaces is a major process involved in protein microarrays. Understanding protein-surface interactions is key to improving the performance of protein microarrays, but current understanding of the behavior of proteins on surfaces is lacking. Prevailing theories on the subject, which suggest that proteins should be stabilized when tethered to surfaces, do not explain the experimentally observed fact that proteins are often denatured on surfaces. This document outlines several studies done to develop a model which is capable of predicting the stabilization and destabilization of proteins tethered to surfaces. As the start point of the research, part …

Understanding The Capabilities And Limitations Of Advanced Interactive M&S: A Cricothyroidotomy Simulation Case Study, Lillian Campbell-Wynn

Electronic Theses and Dissertations

Simulation for surgical education and training is increasingly perceived as a valuable contribution to traditional teaching methods providing a structured learning experience. Surgical simulations allow surgeons to practice tactics, techniques and procedures numerous times without the cost, limitations and ethical problems of using cadaver-based models. The goal of this research is to advance the use of modeling and simulation in support of emergency medical training. This research explores questions identified through a case study of two different modeling and simulation techniques – virtual reality and mannequins - in the support of combat emergency medical education and training. To reduce the …

Modeling And Simulation Of All-Electric Aircraft Power Generation And Actuation, David Woodburn

Electronic Theses and Dissertations

Modern aircraft, military and commercial, rely extensively on hydraulic systems. However, there is great interest in the avionics community to replace hydraulic systems with electric systems. There are physical challenges to replacing hydraulic actuators with electromechanical actuators (EMAs), especially for flight control surface actuation. These include dynamic heat generation and power management. Simulation is seen as a powerful tool in making the transition to all-electric aircraft by predicting the dynamic heat generated and the power flow in the EMA. Chapter 2 of this dissertation describes the nonlinear, lumped-element, integrated modeling of a permanent magnet (PM) motor used in an EMA. …

A Compiler-Based Framework For Automatic Extraction Of Program Skeletons For Exascale Hardware/Software Co-Design, Amruth Rudraiah Dakshinamurthy

Electronic Theses and Dissertations

The design of high-performance computing architectures requires performance analysis of largescale parallel applications to derive various parameters concerning hardware design and software development. The process of performance analysis and benchmarking an application can be done in several ways with varying degrees of fidelity. One of the most cost-effective ways is to do a coarse-grained study of large-scale parallel applications through the use of program skeletons. The concept of a “program skeleton” that we discuss in this paper is an abstracted program that is derived from a larger program where source code that is determined to be irrelevant is removed for …

Development Of An In Situ Measurement Device For Obtaining Material Thermal Properties, Mark A. Hepokoski

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

This thesis presents a methodology for measuring thermal properties in situ, with a special focus on obtaining properties of layered stack-ups commonly used in armored vehicle components. The technique involves attaching a thermal source to the surface of a component, measuring the heat flux transferred between the source and the component, and measuring the surface temperature response. The material properties of the component can subsequently be determined from measurement of the transient heat flux and temperature response at the surface alone. Experiments involving multilayered specimens show that the surface temperature response to a sinusoidal heat flux forcing function is also …

Increased Capacity For Vdl Mode 2 Aeronautical Data Communication, Sanjin Đerić

ETD Archive

VDL Mode 2 is the principal data communication technology for aeronautical communications implemented in the NextGen project for the National Airspace System (NAS), with potentially worldwide service. Aeronautical communications have strict transmission delay standards for safety considerations. Meeting the strict standards significantly drops the capacity of the number of aircraft that can communicate using the Very High Frequency (VHF) Data Radio (VDR). In this thesis, three methods of increasing the capacity while maintaining the strict standards are evaluated: transmit power control, load regulation and ground station placement. A simulation model using OPNET software is used for testing. Load regulation shows …

Exploration Of The Impact Of Affective Variables On Human Performance In A Live Simulation, Ken Westerlund

Electronic Theses and Dissertations

Live simulations play an important role in allowing users to practice and develop skills they learn in training. Although live simulations are playing an increasingly important role in training, ways to improve them are not well understood or documented. In order to improve the efficacy of live simulation and maximize results from funds spent on training; this research examines the relationship between the affective variables of the participants and their performance in the live simulation. Prior to participating in the instructor development live simulation used in this study two training preference scales were administered to a group of trainees. These …

Packet Coalescing And Server Substitution For Energy-Proportional Operation Of Network Links And Data Servers, Mehrgan Mostowfi

USF Tampa Graduate Theses and Dissertations

Electricity generation for Information and Communications Technology (ICT) contributes over 2% of the human-generated CO2 to the atmosphere. Energy costs are rapidly becoming the major operational expense for ICT and may soon dwarf capital expenses as software and hardware continue to drop in price. In this dissertation, three new approaches to achieving energy-proportional operation of network links and data servers are explored.

Ethernet is the dominant wireline communications technology for Internet connectivity. IEEE 802.3az Energy Efficient Ethernet (EEE) describes a Low Power Idle (LPI) mechanism for allowing Ethernet links to sleep. A method of coalescing packets to consolidate link idle …

A Methodology For Scheduling Operating Rooms Under Uncertainty, Marbelly Paola Davila

USF Tampa Graduate Theses and Dissertations

An operating room (OR) is considered to be one of the most costly functional areas within hospitals as well as its major profit center. It is known that managing an OR department is a challenging task, which requires the integration of many actors (e.g., patients, surgeons, nurses, technicians) who may have conflicting interests and priorities.

Considering these aspects, this dissertation focuses on developing a simulation based methodology for scheduling operating rooms under uncertainty, which reflects the complexity, uncertainty and variability associated with surgery.

We split the process of scheduling ORs under uncertainty into two main components. First, we designed a …

A Study On Lane-Change Recognition Using Support Vector Machine, Weiping Deng

USF Tampa Graduate Theses and Dissertations

This research focuses primary on recognition of lane-change behaviors using support vector machines (SVMs). Previous research and statistical results show that the vast majority of motor vehicle accidents are caused by driver behavior and errors. Therefore, the interpretation and evaluation of driver behavior is important for road safety analysis and improvement. The main limit to understanding driver behavior is the data availability. In particular, a full-scale lane-change data set is difficult to collect in a real traffic environment because of the safety and cost issues. Considering the data demands of the recognition model development and the obstacles of field data …

Modeling And Simulation Of Surface Profile Forming Process Of Microlenses And Their Application In Optical Interconnection Devices, Zhengyu Miao

LSU Doctoral Dissertations

Free space micro-optical systems require to integrate microlens array, micromirrors, optical waveguides, beam splitter, etc. on a single substrate. Out-of-plane microlens array fabricated by direct lithography provides pre-alignment during mask fabrication stage and has the advantage of mass manufacturing at low cost. However, this technology requires precise control of the surface profile of microlenses, which is a major technical challenge. The quality control of the surface profile of microlenses limits their applications. In this dissertation, the surface forming process of the out-of-plane microlenses in UV-lithography fabrication was modeled and simulated using a simplified cellular automata model. The microlens array was …

Evaluating The E-Consult Process For Diabetes Care Delivery At An Outpatient Care Clinic, Brian M. Zoll

Browse all Theses and Dissertations

The occurrence of one of the most common chronic conditions in the U.S., diabetes, is expected to rise 53% from 24 million cases in 2003 to 37 million cases in 2023. The U.S. Veterans Health Administration (VHA) is not immune to this. The VHA has experienced an $820 million increase spending on diabetes patients between 2000 and 2008. The VHA has tried to keep the growth of chronic care costs in check through improvements in patient access to care by expanding its network of community-based outpatient clinics. Other methods the VHA has used to curb chronic care spending costs are …

Dynamic Simulation Of Turbine Engine Used With Molten Carbonate Fuel Cell For Power Generation In The Megawatt Range, Carlos Eduardo Gutierrez

Browse all Theses and Dissertations

Molten carbonate fuel cells (MCFC) have a high operating temperature of approximately 650° C (1200° F) to achieve sufficient conductivity of its carbonate electrolyte. Therefore, a gas turbine engine coupled with a MCFC is desirable since the turbine engine can be used to provide hot gas to the cathode, and the cathode gas residue can be used to raise the temperature of the natural gas and water vapor mixture (fuel) before it enters the MCFC at the anode. Dynamic models of a hybrid power plant consisting of a gas turbine engine and a MCFC with their respective components were developed …