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Full-Text Articles in Engineering

Vision-Based Framework For Monitoring Of Eating Behavior Of Persons With Alzheimer’S Disease, Haitham Al-Anssari Dec 2018

Vision-Based Framework For Monitoring Of Eating Behavior Of Persons With Alzheimer’S Disease, Haitham Al-Anssari

Dissertations

Dementia is a syndrome used to describe an array of significant declines in cognitive abilities due to progressive and irreversible loss of neurons and brain functioning. This neurodegeneration seriously affects daily life activities like driving, shopping, working and speaking. Among these, Alzheimer’s disease is the most common type of dementia, with individuals experiencing loss of memory and thinking and reasoning skills. Due to cognitive decline, individuals with Alzheimer’s often suffer from malnutrition, since they do not eat, even when food is presented, and must be fed with assistance. This assistance presents a significant burden of time to caregivers, and consequently …


Integrated Compressive Sensing And Feature Descriptors- A Framework For Facial Recognition Systems, Ali Kadhem Jaber Dec 2018

Integrated Compressive Sensing And Feature Descriptors- A Framework For Facial Recognition Systems, Ali Kadhem Jaber

Dissertations

Facial recognition is still a challenge in many applications, particularly in surveillance, security systems, and human-computer interactive (HCI) tools. The impact of real-world environmental variations on the performance of any facial recognition system can be significant. These variations may include illumination, facial expressions, poses, disguises (facial hair, glasses or cosmetics) and partial face occlusion. Furthermore, the number of images (samples) needed for facial recognition systems can be very large, much larger than what is typically required by an algorithm, and this is often made worse with expansion of the feature space dimensionality. Truly, the “curse of dimensionality” haunts any real-time …


Hybrid Processes In Material Removal Of Hard And Brittle Materials, Hossein Mohammadi Dec 2018

Hybrid Processes In Material Removal Of Hard And Brittle Materials, Hossein Mohammadi

Dissertations

New technologies demand new materials with better mechanical, optical, and thermal properties. Materials that are light weight, strong with high resistance to high temperatures, and compatible with a predetermined condition. Such materials usually are challenging to manufacture and process compared to widely available materials such as metals. Ceramics and semiconductors are considered extremely hard and brittle, making them very difficult to cut and manufacture. The other major and fast-growing type of materials are composites (including Ceramic Matrix Composites, CMC) that are also considered very challenging to machine. All these materials have many applications in major industries (i.e. electronics, aerospace, optics, …


Finite Element Modeling And Experimental Characterization Of Knot Configuration Effect On The Mechanical Performance Of Surgical Suture, Arz Y. Qwam Alden Dec 2018

Finite Element Modeling And Experimental Characterization Of Knot Configuration Effect On The Mechanical Performance Of Surgical Suture, Arz Y. Qwam Alden

Dissertations

Tendon injuries in orthopedic surgery and sports medicine are escalating; hence there is great interest in improving tendon repair. The integrity of tendon repair depends in part on a combination of suture material, suture size and knot configuration. Recent studies have indicated the failure of surgical knots as a failure mode during surgical repair. Further, there is still no consensus on the ideal (best/safest) surgical knot techniques. Also, this failure mode is related to stress concentrations, which cannot be easily established with traditional tensile testing. Most researchers have focused on the measurement and comparison of the gross structural response of …


Retinex-Based Visibility Enhancement System For Inclement Weather With Tracking And Distance Estimation Capabilities, Marwan S. Alluhaidan Dec 2018

Retinex-Based Visibility Enhancement System For Inclement Weather With Tracking And Distance Estimation Capabilities, Marwan S. Alluhaidan

Dissertations

Road conditions affected by weather are well known to have an impact on the number of vehicle accidents and fatalities, due to low- to no-visibility conditions. According to the U.S. Department of Transportation, there are more than 1,259,000 crashes each year. On average, 6,000 people are killed and more than 445,000 people are injured annually due to severe weather conditions. These accidents could be significantly reduced if real-time visibility enhancement systems were made available. However, eliminating the impact of weather conditions on visibility is still lacking and beyond our control. The time has come to develop technology that is capable …


Analysing Online User Activity To Implicitly Infer The Mental Workload Of Web-Based Tasks Using Defeasible Reasoning, Paul Mara Sep 2018

Analysing Online User Activity To Implicitly Infer The Mental Workload Of Web-Based Tasks Using Defeasible Reasoning, Paul Mara

Dissertations

Mental workload can be considered the amount of cognitive load or effort used over time to complete a task in a complex system. Determining the limits of mental workload can assist in optimising designs and identify if user performance is affected by that design. Mental workload has also been presented as a defeasible concept, where one reason can defeat another and a 5-layer schema to represent domain knowledge to infer mental workload using defeasible reasoning has compared favourably to state-of-the-art inference techniques. Other previous work investigated using records of user activity for measuring mental workload at scale using web-based tasks …


Temporal And Spatial Effects Of Shock Overpressure On Blood-Brain Barrier Permeability In Blast-Induced Traumatic Brain Injury, Matthew Joseph Kuriakose Aug 2018

Temporal And Spatial Effects Of Shock Overpressure On Blood-Brain Barrier Permeability In Blast-Induced Traumatic Brain Injury, Matthew Joseph Kuriakose

Dissertations

Exposure to shock waves is the leading cause of traumatic brain injury (TBI) in military personnel and blast-induced TBI (bTBI) is considered the signature wound in recent conflicts in Iraq and Afghanistan. Many researchers attempt to replicate field-relevant shock waves in laboratory settings through the use of gas-driven shock tubes in order to investigate the generation and propagation of shock waves and also explore possible mechanisms of bTBI. Among several injury mechanisms of bTBI, damage to the blood-brain barrier (BBB) has been identified as a potential candidate and has been the focus of several clinical and experimental investigations aimed to …


Cellulose-Derived Glycosaminoglycan Mimetic For Use In Cartilage Tissue Engineering Strategies, Roseline Dominic Menezes Aug 2018

Cellulose-Derived Glycosaminoglycan Mimetic For Use In Cartilage Tissue Engineering Strategies, Roseline Dominic Menezes

Dissertations

Articular cartilage has limited healing and self-repair capability due to the absence of vasculature, lymphatic vessels, and nerves. Damage to articular cartilage becomes irreversible leading to formation of osteoarthritis that could severely degrade a person's quality of life. Approximately, 5-10% of cartilage tissue is made up of glycosaminoglycans (GAG), which sequester growth factors as well as provide structural integrity to the native cartilage tissue. Transforming growth factor-beta3 (TGF-β3) is an important growth factor for inducing chondrogenesis in mesenchymal stem cells (MSCs). Bioavailability of TGF-β3 plays a critical role in cartilage repair both in vitro and in vivo. This study evaluates …


Screen Printed Moisture Sensor On Barrier Coated Sbs Board: The Characterizations Of The Hemicellulose-Based Biofilms And Their Applications For Smart Packaging, Ruoxi Ma Aug 2018

Screen Printed Moisture Sensor On Barrier Coated Sbs Board: The Characterizations Of The Hemicellulose-Based Biofilms And Their Applications For Smart Packaging, Ruoxi Ma

Dissertations

Fiber-based packaging materials have many advantages over their petroleum-based plastic competitors, such as sustainability, recyclability and stiffness/weight ratio. However, the poor barrier properties and sensitivity towards moisture are the main challenges for their extended use. Therefore, there has been a need to provide a biodegradable and biocompatible biopolymer packaging material with improved barrier properties for food and pharmaceutical packaging. Also, the moisture loss/gain problem causes a lot of waste every year. Therefore, there is a need of better tracking and sensing methods attached to the package in order to control the moisture level along the supply chain. To accomplish these …


Decomposition And Ionization Of Ionic Liquids, Forrest Grady Kidd Iii Aug 2018

Decomposition And Ionization Of Ionic Liquids, Forrest Grady Kidd Iii

Dissertations

The United States Air Force is interested in developing a situationally responsive space environment. In order to achieve this, dual-mode-propulsion will be utilized. A new class of propellants is being developed for this application based on energetic ionic liquids. Two ionic liquids of current interest are Hydroxylammonium Nitrate (HAN) and Hydroxyethylhydrazinium Nitrate (HEHN) due to their beneficial performance characteristics. The decomposition and ionization chemistry of these two species is investigated in this work. Using GAUSSIAN09 software, reactions with important radicals are explored through quantum chemistry. The energetics of reactions as well as the identity of key product complexes are given. …


Practical Vortex Beam Generation, Nedime Pelin Mohamed Hassan Salem Jul 2018

Practical Vortex Beam Generation, Nedime Pelin Mohamed Hassan Salem

Dissertations

Vector vortex beams are monochromatic electromagnetic wave fields carrying spin angular momentum (SAM) and orbital angular momentum (OAM). Spin angular momentum is associated with the polarization of the field, whereas OAM yields an azimuthal field dependence of the form exp( jqφ), where φ is the azimuthal angle, and q is an integer designating the helicity order, which is also known as the topological charge of the vortex beam. Vortex beams owe their names to the characteristic on-axis phase singularity and amplitude null.

In this study, a new method to generate vector vortex beams in the microwave regime is devised …


An Integrated Decision Support Framework For Life-Cycle Building Asset Management, Maha Reda Alkasisbeh Jun 2018

An Integrated Decision Support Framework For Life-Cycle Building Asset Management, Maha Reda Alkasisbeh

Dissertations

Building assets are essential to the economic, cultural, and historical growth of any nation. Examples of buildings include shelters, entertainment facilities, living spaces, teaching facilities, civil offices, parking structures, police buildings, libraries, and service areas used to accommodate human activity. Deterioration of building assets, inadequate renewal budgets, climbing deficits, and increasing demand levels are difficulties that face owners when managing building assets. The role of asset management has recently become significant in municipal governments for strategic, operational, and financial reasons. The main functions of an asset management system include assessment of the current condition, prediction of future deterioration, asset prioritization, …


Deterioration Prediction Modeling For The Condition Assessment Of Concrete Bridge Decks, Aqeed Moshin Chyad Jun 2018

Deterioration Prediction Modeling For The Condition Assessment Of Concrete Bridge Decks, Aqeed Moshin Chyad

Dissertations

Bridges are key elements in the US transportation system. There are more than six hundred thousand bridges on the highway system in the United States. Approximately one third of these bridges are in need of maintenance and will cost more than $120 billion to rehabilitate or repair. Several factors affect the performance of bridges over their life spans. Identifying these factors and accurately assessing the condition of bridges are critical in the development of an effective maintenance program. While there are several methods available for condition assessment, selecting the best technique remains a challenge. Therefore, developing an accurate and reliable …


Optimized Insulation And Filter Design Of Rotating Machines Fed By Fast Front Pulses, Mohammed Khalil Hussain Jun 2018

Optimized Insulation And Filter Design Of Rotating Machines Fed By Fast Front Pulses, Mohammed Khalil Hussain

Dissertations

AC rotating machines are exposed to fast front pulses when fed from inverters. This type of excitation produces dielectric stress in the machine’s insulation system that can result in premature deterioration or even failure.

In this dissertation, a non-uniform transmission line model to predict the transient voltage distribution in a machine coil under steep-fronted surge conditions is described and implemented. This model is a function not only of frequency but also of space to represent the variation of electrical parameters in the overhang and slot regions of the coil. These parameters are computed using the finite element method. In order …


Measurements Of Fluid Structures And Mass Transport In Channel With Fabric Base, Karl David Mcallister Jun 2018

Measurements Of Fluid Structures And Mass Transport In Channel With Fabric Base, Karl David Mcallister

Dissertations

This thesis studies the relationships between flow structures and mass transport (dye concentration) within a Poiseuelle water flow glass chamber using optical flow experimental techniques in turbulent conditions. Through optical flow methods, velocity, vorticity, kinetic energy, Reynolds stress and turbulent production metrics where determined by laser illuminated glass beads and Rhodamine 6G dye removing from three different fabric substrates for multiple horizontal planes and one vertical plane. From the dye intensity, mass concentration metrics were determined providing visualization of velocity and mass transport simultaneously along with kinetic energy, mass flux, and concentration fluctuations.


A 3d Simulation Of Leukocyte Adhesion In Blood Flow, Tai-Hsien Wu Jun 2018

A 3d Simulation Of Leukocyte Adhesion In Blood Flow, Tai-Hsien Wu

Dissertations

It has been widely acknowledged that further understanding about the dynamics between blood cells and blood flow can help us gain more knowledge about the causes of diseases and discover more effective treatments. Examples of such dynamics include red blood cell (RBC, or erythrocyte) aggregation, white blood cell (WBC, or leukocyte) margination, and WBC extravasation. WBC extravasation is an important multiple-step process in the inflammatory response and therefore has drawn considerable attention over the past two decades. In this multiple-step process, a WBC undergoes at least four steps, including capture, rolling, firm adhesion, and transmigration, and each step is influenced …


Online Edge Caching And Wireless Delivery In Fog-Aided Networks, Seyyed Mohammadreza Azimi May 2018

Online Edge Caching And Wireless Delivery In Fog-Aided Networks, Seyyed Mohammadreza Azimi

Dissertations

Multimedia content is the significant fraction of transferred data over the wireless medium in the modern cellular and wireless communication networks. To improve the quality of experience perceived by users, one promising solution is to push the most popular contents as close as to users, also known as the "edge" of network. Storing content at the edge nodes (ENs) or base stations (BSs) is called "caching". In Fog Radio Access Network (F-RAN), each EN is equipped with a cache as well as a "fronthaul" connection to the content server. Among the new design problems raised by the outlined scenarios, two …


Borehole Communication Via Drill Strings In Oil Wells, Ali Hamdan Alenezi May 2018

Borehole Communication Via Drill Strings In Oil Wells, Ali Hamdan Alenezi

Dissertations

The performance of multichannel and single channel accelerometers used as uphole communication receivers is studied. Using measured channels from the drill string testbed, it is shown that one tri-axial accelerometer can provide nearly uncorrelated signals when compared to two single channel accelerometers. Having uncorrelated signals at the uphole receiver provides a diversity which in turn can lead to an increase in the communication system performance. The use of a strain sensor as a receiver in borehole communication is proposed. Using measured channels from the drill string testbed, the performance of a strain receiver with a single-accelerometer receiver is compared. The …


Prediction Of Forelimb Muscle Activities And Movement Phases Using Corticospinal Signals In The Rat, Sinan Gok May 2018

Prediction Of Forelimb Muscle Activities And Movement Phases Using Corticospinal Signals In The Rat, Sinan Gok

Dissertations

The targeted population for this project is primarily patients with high level spinal cord injury (SCI) and individuals with motor neuron diseases (MND). In both SCI and MND cases motor control is interrupted due to lack of communication between the brain and the musculature, although both sides are otherwise functional. The approach in this project is to use neural engineering techniques to restore the motor function that was lost because of an injury or disease.

Brain-computer interfaces (BCIs) attempt to extract the volitional signals from the cortex when the brain's normal outputs to the musculoskeletal system are impaired. However, BCIs …


Secure Entity Authentication, Zuochao Dou May 2018

Secure Entity Authentication, Zuochao Dou

Dissertations

According to Wikipedia, authentication is the act of confirming the truth of an attribute of a single piece of a datum claimed true by an entity. Specifically, entity authentication is the process by which an agent in a distributed system gains confidence in the identity of a communicating partner (Bellare et al.). Legacy password authentication is still the most popular one, however, it suffers from many limitations, such as hacking through social engineering techniques, dictionary attack or database leak. To address the security concerns in legacy password-based authentication, many new authentication factors are introduced, such as PINs (Personal Identification Numbers) …


Decontamination Of The Passaic River Sediments Using Ultrasound With Ozone Nano-Bubbles, Janitha Hewa Batagoda May 2018

Decontamination Of The Passaic River Sediments Using Ultrasound With Ozone Nano-Bubbles, Janitha Hewa Batagoda

Dissertations

The Passaic River is 129km long and flows through the northern New Jersey. During the mid-twentieth century, the U.S. census indicated that there were approximately 2,900 industries along the river bank. The amount of industries established next to the river indicated the inevitable river pollution, which was compounded by lenient environmental protection laws. One of the major contributors of the river pollution was Diamond Alkali Co., which started production of chemicals around 1951 at the 4km marker in the Passaic River.

In 1970, the United States Environmental Protection Agency (U.S. EPA) identified the Passaic River as the second most polluted …


Development And Evaluation Of Cooperative Intersection Management Algorithm Under Connected Vehicles Environment, Slobodan Gutesa May 2018

Development And Evaluation Of Cooperative Intersection Management Algorithm Under Connected Vehicles Environment, Slobodan Gutesa

Dissertations

Recent technological advancements in the automotive and transportation industry established a firm foundation for development and implementation of various automated and connected vehicle (C/AV) solutions around the globe. Wireless communication technologies such as the dedicated short-range communication (DSRC) protocol are enabling instantaneous information exchange between vehicles and infrastructure. Such information exchange produces tremendous benefits with the possibility to automate conventional traffic streams and enhance existing signal control strategies. While many promising studies in the area of signal control under connected vehicle (CV) environment have been introduced, they mainly offer solutions designed to operate a single isolated intersection or they require …


From Geographically Dispersed Data Centers Towards Hierarchical Edge Computing, Abbas Kiani May 2018

From Geographically Dispersed Data Centers Towards Hierarchical Edge Computing, Abbas Kiani

Dissertations

Internet scale data centers are generally dispersed in different geographical regions. While the main goal of deploying the geographically dispersed data centers is to provide redundancy, scalability and high availability, the geographic dispersity provides another opportunity for efficient employment of global resources, e.g., utilizing price-diversity in electricity markets or utilizing locational diversity in renewable power generation. In other words, an efficient approach for geographical load balancing (GLB) across geo-dispersed data centers not only can maximize the utilization of green energy but also can minimize the cost of electricity. However, due to the different costs and disparate environmental impacts of the …


Design, Analysis And Optimization Of Visible Light Communications Based Indoor Access Systems For Mobile And Internet Of Things Applications, Sihua Shao May 2018

Design, Analysis And Optimization Of Visible Light Communications Based Indoor Access Systems For Mobile And Internet Of Things Applications, Sihua Shao

Dissertations

Demands for indoor broadband wireless access services are expected to outstrip the spectrum capacity in the near-term "spectrum crunch". Deploying additional femtocells to address "spectrum crunch" is cost-inefficient due to the "backhaul challenge" and the exorbitant system maintenance. According to an Alcatel-Lucent report, most mobile Internet access traffic happens indoors. To alleviate the "spectrum crunch" and the "backhaul challenge" problems, visible light communication (VLC) emerges as an attractive candidate for indoor wireless access in the 5G architecture. In particular, VLC utilizes LED or fluorescent lamps to send out imperceptible flickering light that can be captured by a smart phone camera …


On Distributed Mobile Edge Computing, Xiang Sun May 2018

On Distributed Mobile Edge Computing, Xiang Sun

Dissertations

Mobile Cloud Computing (MCC) has been proposed to offload the workloads of mobile applications from mobile devices to the cloud in order to not only reduce energy consumption of mobile devices but also accelerate the execution of mobile applications. Owing to the long End-to-End (E2E) delay between mobile devices and the cloud, offloading the workloads of many interactive mobile applications to the cloud may not be suitable. That is, these mobile applications require a huge amount of computing resources to process their workloads as well as a low E2E delay between mobile devices and computing resources, which cannot be satisfied …


Assessing The Effectiveness Of Managed Lane Strategies For The Rapid Deployment Of Cooperative Adaptive Cruise Control Technology, Zijia Zhong May 2018

Assessing The Effectiveness Of Managed Lane Strategies For The Rapid Deployment Of Cooperative Adaptive Cruise Control Technology, Zijia Zhong

Dissertations

Connected and Automated Vehicle (C/AV) technologies are fast expanding in the transportation and automotive markets. One of the highly researched examples of C/AV technologies is the Cooperative Adaptive Cruise Control (CACC) system, which exploits various vehicular sensors and vehicle-to-vehicle communication to automate vehicular longitudinal control. The operational strategies and network-level impacts of CACC have not been thoroughly discussed, especially in near-term deployment scenarios where Market Penetration Rate (MPR) is relatively low. Therefore, this study aims to assess CACC's impacts with a combination of managed lane strategies to provide insights for CACC deployment. The proposed simulation framework incorporates 1) the Enhanced …


Submandibular Mechanical Stimulation Of Upper Airway Muscles To Treat Obstructive Sleep Apnea, Ferhat Erdogan May 2018

Submandibular Mechanical Stimulation Of Upper Airway Muscles To Treat Obstructive Sleep Apnea, Ferhat Erdogan

Dissertations

The extrinsic tongue muscles are activated in coordination with pharyngeal muscles to keep a patent airway during respiration in wakefulness and sleep. The activity of genioglossus, the primary tongue-protruding muscle playing an important role in this coordination, is known to be modulated by several reflex pathways mediated through the mechanoreceptors of the upper airways. The main objective is to investigate the effectiveness of activating these reflex pathways with mechanical stimulations, for the long-term goal of improving the upper airway patency during disordered breathing in sleep. The genioglossus response is examined during mandibular and sub-mandibular mechanical stimulations in healthy subjects during …


Fluorescent Probes And Functionalized Nanoparticles For Bioimaging: Synthesis, Photophysical Properties And Applications, Xinglei Liu May 2018

Fluorescent Probes And Functionalized Nanoparticles For Bioimaging: Synthesis, Photophysical Properties And Applications, Xinglei Liu

Dissertations

The development of new organic molecular probes with excellent photophysical properties and high fluorescence quantum yields is of considerable interest to many research areas including one- and two-photon fluorescence microscopy, fluorescence-based sensing methodologies, and cancer therapy. Series of organic linear-/non-linear optical molecules including squaraine derivatives, and fluorene derivatives as well as other bioconjugates are designed and synthesized during the doctoral study for the aim of ion detection (Chapter 5), photo dynamic therapy, and deep-tissue imaging (Chapter 4). These optical probes are capable of absorbing light in the near infrared (NIR) window and thus have deeper penetration and cause less photodamage …


Silicon Based Uncooled Microbolometer, Asahel Banobre May 2018

Silicon Based Uncooled Microbolometer, Asahel Banobre

Dissertations

During the last decade, uncooled microbolometer infrared detectors have attracted the attention of military and civilian infrared detection and imaging industry due to their significant advantages. In actuality, infrared imaging systems play a critical role in sectors such as thermography (predictive maintenance and building inspection), commercial and civilian applications (vision automotive, surveillance, navigation and fire-fighting), and defense industry (thermal weapon sight, soldier vision and vehicle vision enhancer). Compared with the cryogenically cooled infrared photon detectors, uncooled infrared imaging technology offers advantages such as operation at room temperature, light weight and size, reduced power consumption, easy integration with read-out electronics and …


Kinetic Study Of Free Radical-Radical Reactions Of Combustion Importance At Elevated Pressures, Chao Yan May 2018

Kinetic Study Of Free Radical-Radical Reactions Of Combustion Importance At Elevated Pressures, Chao Yan

Dissertations

Combustion mechanisms consist of hundreds elementary reactions of free radicals and stable molecules. Radical-radical elementary reactions play important roles due to the high concentration in which free radicals are accumulated in combustion systems. Radical-radical reactions are typically multi-channel. Some of the channels might be of chain propagation or even chain branching nature, while other channels might be of chain termination nature. The relative importance of different channels is pressure dependent. Compared to radical-molecule reactions, radical-radical reactions are much less studied. This is due to the difficulties of well characterized quantitative production of radical species as well as due to the …