Engineering Commons^™

Shock Tube And Mid-Infrared Laser Absorption Measurements Of Ignition Delay Times And Species Time-Histories, Batikan Koroglu

Electronic Theses and Dissertations

Energy consumption has increased dramatically as the world advances and becomes more industrialized. Over the next twenty five years, the U.S. Department of Energy expects the energy demand to increase by 29% with majority of the new energy coming from natural gas (methane). Another promising fuel source for power generation and transportation is the biofuels. The biofuel use in the US is shown to have increased substantially in the last decade. There are serious environmental concerns associated with greenhouse (e.g. carbon-dioxide) and toxic gas emissions (e.g. nitrogen oxides and aldehydes such as propanal) due to deriving energy from natural gas …

Phase Transformation And Growth Kinetics In Reaction Zone Between Uranium Alloy And Zirconium Diffusion Barrier, Young Joo Park

Electronic Theses and Dissertations

U-10wt.%Mo (U10Mo) alloy as a part of monolithic fuel system is being developed under Material Management and Minimization Reactor Conversion (MMMRC) program, tasked with replacing high-enriched uranium (HEU) fuel with low-enriched uranium (LEU) fuel in civilian research and test reactors. Use of U10Mo fuel alloy entails a Zr diffusion barrier to avoid the undesirable interdiffusion and reactions between the U10Mo and Al-alloy cladding. To better understand the interaction between these fuel system constituents, microstructural development and diffusion kinetics in U-Mo-Zr, U-Zr and fuel plate assembly processed by co-rolling and hot isostatic pressing (HIP) were investigated using a variety of analytical …

Estimating A Freight Mode Choice Model: A Case Study Of Commodity Flow Survey 2012, Nowreen Keya

Electronic Theses and Dissertations

This research effort develops a national freight mode choice model employing data from the 2012 Commodity Flow Survey (CFS). While several research efforts have developed mode choice model with multiple modes in the passenger travel context, the literature is sparse in the freight context. The primary reasons being unavailability and/or the high cost associated with the acquisition of mode choice and level of service (LOS) measures – such as travel time and travel cost. The first contribution of the research effort is to develop travel time and cost measures for various modes reported in the CFS. The study considers five …

Modeling And Compensation For Efficient Human Robot Interaction, Nicholas Paperno

Electronic Theses and Dissertations

The purpose of this research is to first: identify the important human factors to performance when operating an assistive robotic manipulator, second: develop a predictive model that will be able to determine a user's performance based on their known human factors, and third: develop compensators based on the determined important human factors that will help improve user performance and satisfaction. An extensive literature search led to the selection of ten potential human factors to be analyzed including reaction time, spatial abilities (orientation and visualization), working memory, visual perception, dexterity (gross and fine), depth perception, and visual acuity of both eyes …

A Framework For Quantifying And Managing Overcrowding In Healthcare Facilities, Abdulrahman Albar

Electronic Theses and Dissertations

Emergency Departments (EDs) represent a crucial component of any healthcare infrastructure. In today's world, healthcare systems face growing challenges in delivering efficient and time-sensitive emergency care services to communities. Overcrowding within EDs represents one of the most significant challenges for healthcare quality that adversely impacts clinical outcomes, patient safety, and overall satisfaction. Research in this area has resulted in creating several ED crowding indices, such as National Emergency Department Overcrowding Scale (NEDOCS) and Emergency Department Work Index (EDWIN) that have been developed to provide measures aimed at mitigating overcrowding. Recently, efforts made by researchers to examine the validity and reproducibility …

A Neuroergonomics Study Of Brain Eeg's Activity During Manual Lifting Tasks, Awad Aljuaid

Electronic Theses and Dissertations

Electroencephalography (EEG) has been shown to be a reliable tool in neuroergonomics studies due to the relatively low cost of brain data collection and limited body invasion. The application of EEG frequency bands (including theta, alpha and beta), enjoyed a wide range of interest in physical and cognitive ergonomics. The psychophysical approach has been used for decades to improve safe work practices by understanding human limitations in manual materials handling. The main objective of this research project was to study the brain's EEG activity expressed by the power spectral density during manual lifting tasks related to: 1) the maximum acceptable …

Computational Methods For Comparative Non-Coding Rna Analysis: From Secondary Structures To Tertiary Structures, Ping Ge

Electronic Theses and Dissertations

Unlike message RNAs (mRNAs) whose information is encoded in the primary sequences, the cellular roles of non-coding RNAs (ncRNAs) originate from the structures. Therefore studying the structural conservation in ncRNAs is important to yield an in-depth understanding of their functionalities. In the past years, many computational methods have been proposed to analyze the common structural patterns in ncRNAs using comparative methods. However, the RNA structural comparison is not a trivial task, and the existing approaches still have numerous issues in efficiency and accuracy. In this dissertation, we will introduce a suite of novel computational tools that extend the classic models …

Performance Evaluation Of Connectivity And Capacity Of Dynamic Spectrum Access Networks, Osama Al-Tameemi

Electronic Theses and Dissertations

Recent measurements on radio spectrum usage have revealed the abundance of under- utilized bands of spectrum that belong to licensed users. This necessitated the paradigm shift from static to dynamic spectrum access (DSA) where secondary networks utilize unused spectrum holes in the licensed bands without causing interference to the licensed user. However, wide scale deployment of these networks have been hindered due to lack of knowledge of expected performance in realistic environments and lack of cost-effective solutions for implementing spectrum database systems. In this dissertation, we address some of the fundamental challenges on how to improve the performance of DSA …

Application Of Landfill Treatment Approaches For The Stabilization Of Municipal Solid Waste, Stephanie Bolyard

Electronic Theses and Dissertations

This research focused on the fundamental requirements of stabilizing a mature landfill using three treatment approaches as well as the implications of discharging leachate organic matter (LOM) to wastewater treatment plants (WWTPs). Three treatment approaches aimed at removing releasable carbon and nitrogen from mature landfills including flushing with clean water, leachate recirculation with ex-situ chemical oxidation, and leachate recirculation with ex-situ chemical oxidation and in-situ aeration were evaluated. After extensive treatment of the waste in the flushing bioreactor (FB) scenarios, the overall biodegradable fraction was reduced relative to mature waste. Leachate quality improved for all FBs but through different mechanisms. …

Cyber-Physical Systems: Complex System Governance As An Integrating Construct, Polinpapilinho F. Katina, Charles B. Keating, Adrian V. Gheorghe

Engineering Management & Systems Engineering Faculty Publications

This paper examines contributions of Complex System Governance (CSG) as an integrating construct for the emerging fields of critical cyber-physical systems (CPS). CPS is concerned with physical entities that are controlled by computational elements. The field is relatively new, emerging, and also somewhat fragmented in development. There are multiple agencies, entities, and activities being undertaken to address a nexus of emerging issues (e.g., cybersecurity) in critical infrastructures. However, the development of critical CPS, as a field, albeit with good intentions and efforts, appears to be largely ‘self-organizing.’ In response, we suggest CSG as an organizing construct capable of provided a …

Performance Analysis Of Secondary Users In Heterogeneous Cognitive Radio Network, Tanjil Amin

College of Graduate Studies: Theses & Dissertations

Continuous increase in wireless subscriptions and static allocation of wireless frequency bands to the primary users (PUs) are fueling the radio frequency (RF) shortage problem. Cognitive radio network (CRN) is regarded as a solution to this problem as it utilizes the scarce RF in an opportunisticmanner to increase the spectrumefficiency. InCRN, secondary users (SUs) are allowed to access idle frequency bands opportunistically without causing harmful interference to the PUs. In CRN, the SUs determine the presence of PUs through spectrum sensing and access idle bands by means of dynamic spectrum access. Spectrum sensing techniques available in the literature do not …

Optimizing Cobalt Carbide Based Nanomaterials By Using Nucleating Agents And Statistical Routes, Turki I. Almugaiteeb

Theses and Dissertations

The continuous high demand on permanent magnets in industries opened new research plateau to develop alternative magnetic material. The current used permanent magnet materials in the market still suffer from high cost and insufficient magnetic or thermal properties. The central focus of this dissertation work is the optimization of cobalt carbide based nanomaterial by means of modifying polyol synthesis assisted by nucleation agent and systematic statistics using JMP software tool. In most existing literatures, producing cobalt carbide (Co₂C or Co₃C) lack reproducibility and consistency resulting in nonsolid magnetic properties results. The practical requirements for cobalt carbide …

Efficiency Evaluation Of A Magnetically Driven Multiple Disk Centrifugal Blood Pump, Kayla H. Moody

Theses and Dissertations

Heart failure is expected to ail over 8 million people in America by 2030 leaving many in need of cardiac replacement. To accommodate this large volume of people, ventricular assist devices (VADs) are necessary to provide mechanical circulatory support. Current VADs exhibit issues such as thrombosis and hemolysis caused by large local pressure drops and turbulent flow within the pump. Multiple disk centrifugal pumps (MDCPs) use shearing and centrifugal forces to produce laminar flow patterns and eliminate large pressure drops within the pump which greatly reduce risks that are in current VADs. The MDCP has a shaft drive system (SDS) …

Power Maximization For Pyroelectric, Piezoelectric, And Hybrid Energy Harvesting, Murtadha A. Shaheen

Theses and Dissertations

The goal of this dissertation consists of improving the efficiency of energy harvesting using pyroelectric and piezoelectric materials in a system by the proper characterization of electrical parameters, widening frequency, and coupling of both effects with the appropriate parameters.

A new simple stand-alone method of characterizing the impedance of a pyroelectric cell has been demonstrated. This method utilizes a Pyroelectric single pole low pass filter technique, PSLPF. Utilizing the properties of a PSLPF, where a known input voltage is applied and capacitance C_p and resistance R_p can be calculated at a frequency of 1 mHz to 1 Hz. …

Development And Characterization Of Lung Derived Extracellular Matrix Hydrogels, Robert A. Pouliot

Theses and Dissertations

Chronic obstructive pulmonary disease (COPD) including emphysema is a devastating condition, increasing in prevalence in the US and worldwide. There remains no cure for COPD, rather only symptomatic treatments. Due to unique challenges of the lung, translation of therapies for acute lung injury to target chronic lung diseases like COPD has not been successful. We have been investigating lung derived extracellular matrix (ECM) hydrogels as a novel approach for delivery of cellular therapies to the pulmonary system.

During the course of this work we have developed and characterized a lug derived ECM hydrogel that exhibits “injectability,” allowing cells or dugs …

An Injectable Stem Cell Delivery System For Treatment Of Musculoskeletal Defects, Shirae Leslie

Theses and Dissertations

The goal of this research was to develop a system of injectable hydrogels to deliver stem cells to musculoskeletal defects, thereby allowing cells to remain at the treatment site and secrete soluble factors that will facilitate tissue regeneration. First, production parameters for encapsulating cells in microbeads were determined. This involved investigating the effects of osmolytes on alginate microbead properties, and the effects of alginate microbead cell density, alginate microbead density, and effects of osteogenic media on microencapsulated cells. Although cells remained viable in the microbeads, alginate does not readily degrade in vivo for six months. Therefore, a method to incorporate …

A Computational Study Of Curvature In The Outflow Graft Of A Continuous Flow Left Ventricular Assist Device, Laura Patterson

Theses and Dissertations

Left ventricular assist devices (LVADs) are an increasingly utilized therapy for end-stage heart failure. Thrombosis within the graft from the pump to the aorta has been documented, but is poorly researched. This study examines the effect of graft geometry, as measured by radius of curvature, bend angle, and diameter, on thrombogenic flow patterns within the graft for a range of flow conditions. It also examines the effect blood properties, including viscosity and density, on these flow patterns. The results indicated that radius of curvature had a powerful effect on thrombogenic flow patterns. Flowrate and bend angle were also influential. The …

Ultra–Low Power Straintronic Nanomagnetic Computing With Saw Waves: An Experimental Study Of Saw Induced Magnetization Switching And Properties Of Magnetic Nanostructures, Vimal G. Sampath

Theses and Dissertations

A recent International Technology Roadmap for Semiconductors (ITRS) report (2.0, 2015 edition) has shown that Moore’s law is unlikely to hold beyond 2028. There is a need for alternate devices to replace CMOS based devices, if further miniaturization and high energy efficiency is desired. The goal of this dissertation is to experimentally demonstrate the feasibility of nanomagnetic memory and logic devices that can be clocked with acoustic waves in an extremely energy efficient manner. While clocking nanomagnetic logic by stressing the magnetostrictive layer of a multiferroic logic element with with an electric field applied across the piezoelectric layer is known …

Using Mavt To Incorporate Public Perception When Choosing A Nuclear Fuel Cycle, Stephen Clement

Theses and Dissertations

Nuclear energy is a source of carbon free power. With many countries striving to make deep carbon cuts in their energy sectors, nuclear energy could be a large part of the solution. One of the main obstacles standing in the way of the use of nuclear energy is the issue of used nuclear fuel disposal. According to the NEI, the U.S. creates about 2000 metric tons of used nuclear fuel per year and has generated around 76,000 metric tons of used nuclear fuel over the last 4 decades. While there are technical problems that need to be solved, it is …

The Dawn Of New Quantum Dots: Synthesis And Characterization Of Ge1-Xsnx Nanocrystals For Tunable Bandgaps., Richard J. Esteves

Theses and Dissertations

Ge_1-xSn_x alloys are among a small class of benign semiconductors with composition tunable bandgaps in the near-infrared spectrum. As the amount of Sn is increased the band energy decreases and a transition from indirect to direct band structure occurs. Hence, they are prime candidates for fabrication of Si-compatible electronic and photonic devices, field effect transistors, and novel charge storage device applications. Success has been achieved with the growth of Ge_1-xSn_x thin film alloys with Sn compositions up to 34%. However, the synthesis of nanocrystalline alloys has proven difficult due to larger discrepancies (~14%) in …

Resilient Dynamic State Estimation In The Presence Of False Information Injection Attacks, Jingyang Lu

Theses and Dissertations

The impact of false information injection is investigated for linear dynamic systems with multiple sensors. First, it is assumed that the system is unaware of the existence of false information and the adversary is trying to maximize the negative effect of the false information on Kalman filter's estimation performance under a power constraint. The false information attack under different conditions is mathematically characterized. For the adversary, many closed-form results for the optimal attack strategies that maximize the Kalman filter's estimation error are theoretically derived. It is shown that by choosing the optimal correlation coefficients among the false information and allocating …

Role Of E-Cadherin Force In The Spatial Regulation Of Cell Proliferation, Abhinav Mohan

Theses and Dissertations

Cell proliferation and contact inhibition play a major role in maintaining epithelial cell homeostasis. A hallmark of epithelial cells is strong cell-cell junctions. These junctions include E-Cadherin, a type of adherens junction that is critical for both barrier function and contact inhibition. Prior experiments by other groups have shown that adherens junctions are subject to mechanical tension. Externally applied forces (e.g. stretch) results in changes in E-Cadherin forces that coordinate proliferation. My current work tests the hypothesis that E-Cadherin forces mediate the spatial regulation of cell proliferation even in the absence of externally applied forces.

Traser: A Traffic Signal Event-Based Recorder, Chenhui Liu, Anuj Sharma, Edward Smaglik, Sirisha Kothuri

Civil and Environmental Engineering Faculty Publications and Presentations

In the past decades, the demand for high-resolution event-based traffic signal indication and detector data has increased due to the need for the collection and reporting of performance measures. This paper will first lay a groundwork for why this type of data acquisition is important, followed by the introduction of a new low-cost, user-friendly, high-resolution traffic signal event-based recorder—TraSER, with integrated video. This paper describes TraSER’s structure, operating principles, and field applications. TraSER allows researchers to be able to collect high-resolution event-based controller data at signalized intersections easily and conveniently. The paper concludes with a discussion on future expansion of …

Detecting And Tracing Slow Attacks On Mobile Phone User Service, Brian Cusack, Zhuang Tian

Australian Digital Forensics Conference

The lower bandwidth of mobile devices has until recently filtered the range of attacks on the Internet. However, recent research shows that DOS and DDOS attacks, worms and viruses, and a whole range of social engineering attacks are impacting on broadband smartphone users. In our research we have developed a metric-based system to detect the traditional slow attacks that can be effective using limited resources, and then employed combinations of Internet trace back techniques to identify sources of attacks. Our research question asked: What defence mechanisms are effective? We critically evaluate the available literature to appraise the current state of …

The Proceedings Of 14th Australian Digital Forensics Conference, 5-6 December 2016, Edith Cowan University, Perth, Australia, Craig Valli

Australian Digital Forensics Conference

Conference Foreword

This is the fifth year that the Australian Digital Forensics Conference has been held under the banner of the Security Research Institute, which is in part due to the success of the security conference program at ECU. As with previous years, the conference continues to see a quality papers with a number from local and international authors. 11 papers were submitted and following a double blind peer review process, 8 were accepted for final presentation and publication. Conferences such as these are simply not possible without willing volunteers who follow through with the commitment they have initially made, …

We Can Hear You With Wi-Fi!, Guanhua Wang, Yongpan Zou, Zimu Zhou, Kaishun Wu, Lionel M. Ni

Research Collection School Of Computing and Information Systems

Recent literature advances Wi-Fi signals to “see” people’s motions and locations. This paper asks the following question: Can Wi-Fi “hear” our talks? We present WiHear, which enables Wi-Fi signals to “hear” our talks without deploying any devices. To achieve this, WiHear needs to detect and analyze fine-grained radio reflections from mouth movements. WiHear solves this micro-movement detection problem by introducing Mouth Motion Profile that leverages partial multipath effects and wavelet packet transformation. Since Wi-Fi signals do not require line-of-sight, WiHear can “hear” people talks within the radio range. Further, WiHear can simultaneously “hear” multiple people’s talks leveraging MIMO technology. We …

Water Demand Forecasting In Al-Ain City, United Arab Emirates, Hebah Ibrahim Younis

Theses

Al-Ain city is the second largest city in the Emirate of Abu Dhabi and the third in the United Arab Emirates (UAE). Currently, desalination plants are the only source of municipal water in Al-Ain city with an average daily supply of 170 MIG. The expected natural population growth, in addition to future projects, will certainly put additional stress on the water resources in the city. Therefore, Al-Ain city seems to be in an urgent need for estimations of future water demands for achieving sustainable development. The main aim of this thesis is to introduce a water demand forecasting model to …

Thermal Envelope Analysis Of Local Authority Low Rise Housing Based On Stock Aggregation Theory Using A Remote Feature Extraction Technique., James Pittam

Theses

Understanding the buildings thermal envelope is paramount to analysing existing problems which facilitate cold bridging and low surface temperatures. As no detailed housing stock database is in existence in Ireland which describes the geometrical configuration of the existing housing stock, and to create one would be a major challenge, this research set out to develop a high speed remote cataloguing and geometrical data extraction methodology to build such a database. Replacing traditional measurement methods with a remote method allows for the rapid extraction of fagade information. A remote surveying process is proposed named, the Virtual Survey Method, for the classification …

Analysis And Modelling Of Sediment Transport On The River Bandon, John Gamble

Theses

Sediment behaviour and transport in river systems has been studied for centuries and potentially impacts on river capacity, navigation, water quality, ecology and flooding. This thesis investigates sediment behaviour and transport on the River Bandon, a river system which has experienced severe flooding on a periodic basis. The River Bandon is located in the South Western River Basin District with a total catchment area of 608km“. The River Bandon offers a positive environment for biodiversity, facilitating habitats for some endangered species. This thesis presents a literature review on the River Bandon and its catchment, on sediment behaviour and transport and …

Performance Enhancement Of Equivalence Principle Algorithm, Xin Fu, Li (Lijun) Jun Jiang, Zu Hui Ma, Shi Quan He

Electrical and Computer Engineering Faculty Research & Creative Works

The conventional equivalence principle algorithm (EPA) exploits cubical surfaces to support equivalent sources. However, it introduces strong discontinuities due to sharp edges and corners. In this letter, a spherical surface is employed as the equivalence surface to avoid singularities from nonsmoothness. To achieve better accuracy, the meshless sampling scheme is used for integral operators on the spherical equivalence surface. The numerical examples are provided to validate the performance enhancement of EPA through the proposed method.