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Full-Text Articles in Engineering

A Game Modeling Of A Closed-Loop Supply Chain In A Water-Energy Nexus: Technology Advancement, Market Competition And Capacity Limit, Nabeel Hamoud Dec 2019

A Game Modeling Of A Closed-Loop Supply Chain In A Water-Energy Nexus: Technology Advancement, Market Competition And Capacity Limit, Nabeel Hamoud

Theses and Dissertations

Water and energy are two scarce and concerning resources interconnected in the water-energy nexus. In the nexus, production of energy needs water, and production of water needs energy. For better management of these resources in the nexus, this research considers a supply chain that consists of water suppliers, power suppliers, and consumers of these commodities. In the chain, water suppliers purchase power from power suppliers, and power suppliers purchase water from water suppliers. Other consumers can also buy these resources at the water and power markets. Each firm tries to maximize its own profit. The suppliers of water and power …


Evaluating The Resiliency Of Industrial Internet Of Things Process Control Using Protocol Agnostic Attacks, Hector L. Roldan Dec 2019

Evaluating The Resiliency Of Industrial Internet Of Things Process Control Using Protocol Agnostic Attacks, Hector L. Roldan

Theses and Dissertations

Improving and defending our nation's critical infrastructure has been a challenge for quite some time. A malfunctioning or stoppage of any one of these systems could result in hazardous conditions on its supporting populace leading to widespread damage, injury, and even death. The protection of such systems has been mandated by the Office of the President of the United States of America in Presidential Policy Directive Order 21. Current research now focuses on securing and improving the management and efficiency of Industrial Control Systems (ICS). IIoT promises a solution in enhancement of efficiency in ICS. However, the presence of IIoT …


Scatter Reduction By Exploiting Behaviour Of Convolutional Neural Networks In Frequency Domain, Carlos Ivan Jerez Gonzalez Dec 2019

Scatter Reduction By Exploiting Behaviour Of Convolutional Neural Networks In Frequency Domain, Carlos Ivan Jerez Gonzalez

Theses and Dissertations

In X-ray imaging, scattered radiation can produce a number of artifacts that greatly

undermine the image quality. There are hardware solutions, such as anti-scatter grids.

However, they are costly. A software-based solution is a better option because it is

cheaper and can achieve a higher scatter reduction. Most of the current software-based

approaches are model-based. The main issues with them are the lack of flexibility, expressivity, and the requirement of a model. In consideration of this, we decided to apply

Convolutional Neural Networks (CNNs), since they do not have any of the previously

mentioned issues.

In our approach we split …


Optimizing Hydrogen Sulfide Removal And Biogas Production Using The Water Wash Method, Brian Leightner Dec 2019

Optimizing Hydrogen Sulfide Removal And Biogas Production Using The Water Wash Method, Brian Leightner

Theses and Dissertations

Biogas forms from decomposing organic material in agricultural digesters, landfills, and wastewater treatment plant digesters. Biogas is mostly composed of methane, and can be used as a carbon-based fuel. Microorganisms that consume organics in these waste streams also produce hydrogen sulfide (H2S) as part of the biogas, in varying trace amounts. H2S is corrosive to engines and pipes for machinery, a human health hazard when inhaled, and an aquatic hazard when dissolved in water. Water washing is an absorption process that dissolves hydrogen sulfide and other water soluble compounds in this process and carries it away from the gas, thereby …


Person Identification With Convolutional Neural Networks, Kang Zheng Oct 2019

Person Identification With Convolutional Neural Networks, Kang Zheng

Theses and Dissertations

Person identification aims at matching persons across images or videos captured by different cameras, without requiring the presence of persons’ faces. It is an important problem in computer vision community and has many important real-world applica- tions, such as person search, security surveillance, and no-checkout stores. However, this problem is very challenging due to various factors, such as illumination varia- tion, view changes, human pose deformation, and occlusion. Traditional approaches generally focus on hand-crafting features and/or learning distance metrics for match- ing to tackle these challenges. With Convolutional Neural Networks (CNNs), feature extraction and metric learning can be combined in …


Cybersecurity Issues In The Context Of Cryptographic Shuffling Algorithms And Concept Drift: Challenges And Solutions, Hatim Alsuwat Oct 2019

Cybersecurity Issues In The Context Of Cryptographic Shuffling Algorithms And Concept Drift: Challenges And Solutions, Hatim Alsuwat

Theses and Dissertations

In this dissertation, we investigate and address two kinds of data integrity threats. We first study the limitations of secure cryptographic shuffling algorithms regarding preservation of data dependencies. We then study the limitations of machine learning models regarding concept drift detection. We propose solutions to address these threats.

Shuffling Algorithms have been used to protect the confidentiality of sensitive data. However, these algorithms may not preserve data dependencies, such as functional de- pendencies and data-driven associations. We present two solutions for addressing these shortcomings: (1) Functional dependencies preserving shuffle, and (2) Data-driven asso- ciations preserving shuffle. For preserving functional dependencies, …


Nonlinear Characterizing Of A New Titanium Nitride On Aluminum Oxide Metalens, Michael A. Cumming Oct 2019

Nonlinear Characterizing Of A New Titanium Nitride On Aluminum Oxide Metalens, Michael A. Cumming

Theses and Dissertations

A sample metalens generated from Titanium Nitride deposited onto Aluminum Oxide was designed to focus at 10 microns with a beam centered at 800nm, and when analyzed with high intensity illumination was found to have a focal length of 9.650 ±.003µm at an intensity of 16.93[MW/cm2 ]. Analyzing this change by comparing it to a Fresnel Lens’ physics shows that for this lens, the effective nonlinear index of refraction is certainly greater than the nonlinear index of just Titanium Nitride itself, at −1.6239 × 10−15[m2/W] compared to the materials −1.3 × 10−15[m2 …


Properties, Learning Algorithms, And Applications Of Chain Graphs And Bayesian Hypergraphs, Mohammad Ali Javidian Oct 2019

Properties, Learning Algorithms, And Applications Of Chain Graphs And Bayesian Hypergraphs, Mohammad Ali Javidian

Theses and Dissertations

Probabilistic graphical models (PGMs) use graphs, either undirected, directed, or mixed, to represent possible dependencies among the variables of a multivariate probability distri- bution. PGMs, such as Bayesian networks and Markov networks, are now widely accepted as a powerful and mature framework for reasoning and decision making under uncertainty in knowledge-based systems. With the increase of their popularity, the range of graphical models being investigated and used has also expanded. Several types of graphs with dif- ferent conditional independence interpretations - also known as Markov properties - have been proposed and used in graphical models.

The graphical structure of a …


Stacked Modelling Framework, Kareem Abdelfatah Oct 2019

Stacked Modelling Framework, Kareem Abdelfatah

Theses and Dissertations

The thesis develops a predictive modeling framework based on stacked Gaussian processes and applies it to two main applications in environmental and chemical en- gineering. First, a network of independently trained Gaussian processes (StackedGP) is introduced to obtain analytical predictions of quantities of interest (model out- puts) with quantified uncertainties. StackedGP framework supports component- based modeling in different fields such as environmental and chemical science, en- hances predictions of quantities of interest through a cascade of intermediate predic- tions usually addressed by cokriging, and propagates uncertainties through emulated dynamical systems driven by uncertain forcing variables. By using analytical first and …


Challenges In Large-Scale Machine Learning Systems: Security And Correctness, Emad Alsuwat Oct 2019

Challenges In Large-Scale Machine Learning Systems: Security And Correctness, Emad Alsuwat

Theses and Dissertations

In this research, we address the impact of data integrity on machine learning algorithms. We study how an adversary could corrupt Bayesian network structure learning algorithms by inserting contaminated data items. We investigate the resilience of two commonly used Bayesian network structure learning algorithms, namely the PC and LCD algorithms, against data poisoning attacks that aim to corrupt the learned Bayesian network model.

Data poisoning attacks are one of the most important emerging security threats against machine learning systems. These attacks aim to corrupt machine learning models by con- taminating datasets in the training phase. The lack of resilience of …


Digital Holography Efficiency Experiments For Tactical Applications, Douglas E. Thornton Sep 2019

Digital Holography Efficiency Experiments For Tactical Applications, Douglas E. Thornton

Theses and Dissertations

Digital holography (DH) uses coherent detection and offers direct access to the complex-optical field to sense and correct image aberrations in low signal-to-noise environments, which is critical for tactical applications. The performance of DH is compared to a similar, well studied deep-turbulence wavefront sensor, the self-referencing interferometer (SRI), with known efficiency losses. Wave optics simulations with deep-turbulence conditions and noise were conducted and the results show that DH outperforms the SRI by 10's of dB due to DH's strong reference. Additionally, efficiency experiments were conducted to investigate DH system losses. The experimental results show that the mixing efficiency (37%) is …


Targeted Germanium Ion Irradiation Of Aluminum Gallium Nitride/Gallium Nitride High Electron Mobility Transistors, Melanie E. Mace Aug 2019

Targeted Germanium Ion Irradiation Of Aluminum Gallium Nitride/Gallium Nitride High Electron Mobility Transistors, Melanie E. Mace

Theses and Dissertations

Microscale beams of germanium ions were used to target different locations of aluminum galliumnitride/gallium nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) to determine location dependent radiation effects. 1.7 MeV Ge ions were targeted at the gap between the gate and the drain to observe displacement damage effects while 47 MeV Ge ions were targeted at the gate to observe ionization damage effects. Electrical data was taken pre, during, and post irradiation. To separate transient from permanent degradation, the devices were characterized after a room temperature anneal for at least 30 days. Optical images were also analyzed pre and post irradiation. …


On The Pulsed Laser Ablation Of Metals And Semiconductors, Todd A. Van Woerkom Aug 2019

On The Pulsed Laser Ablation Of Metals And Semiconductors, Todd A. Van Woerkom

Theses and Dissertations

This dissertation covers pulsed laser ablation of Al, Si, Ti, Ge, and InSb, with pulse durations from tens of picosecond to hundreds of microseconds, fluences from ones of J/cm2 to over 10,000 J/cm2, and in ambient air and vacuum. A set of non-dimensional scaling factors was created to interpret the data relative to the laser and material parameters, and it was found that pulse durations shorter than a critical timescale formed craters much larger than the thermal diffusion length, and longer pulse durations created holes much shallower than the thermal diffusion length. Low transverse order Gaussian beams …


Light Scattering In Diffraction Limit Infrared Imaging, Ghazal Azarfar Aug 2019

Light Scattering In Diffraction Limit Infrared Imaging, Ghazal Azarfar

Theses and Dissertations

Fourier Transform Infrared (FTIR) microspectroscopy is a noninvasive technique for chemical imaging of micrometer size samples. Employing an infrared microscope, an infrared source and FTIR spectrometer coupled to a microscope with an array of detectors (128 x 128 detectors), enables collecting combined spectral and spatial information simultaneously. Wavelength dependent images are collected, that reveal biochemical signatures of disease pathology and cell cycle. Single cell biochemistry can be evaluated with this technique, since the wavelength of light is comparable to the size of the objects of interest, which leads to additional spectral and spatial effects disturb biological signatures and can confound …


Multi-Tap Extended Kalman Filter For A Periodic Waveform With Uncertain Frequency And Waveform Shape, And Data Dropouts, Justin Saboury Aug 2019

Multi-Tap Extended Kalman Filter For A Periodic Waveform With Uncertain Frequency And Waveform Shape, And Data Dropouts, Justin Saboury

Theses and Dissertations

Gait analysis presents the challenge of detecting a periodic waveform in the presence of time varying frequency, amplitude, DC offset, and waveform shape, with acquisition gaps from partial occlusions. The combination of all of these components presents a formidable challenge. The Extended Kalman Filter for this system model has six states, which makes it weakly identifiable within the standard Extended Kalman Filter network. In this work, a novel robust Extended Kalman Filter-based approach is presented and evaluated for clinical use in gait analysis. The novel aspect of the proposed method is that at each sample, the present and several past …


Optimizing Self-Healing Wind Turbine Blades Utilizing Dicyclopentadiene Infused Vascular Networks, Giovanni Lewinski Aug 2019

Optimizing Self-Healing Wind Turbine Blades Utilizing Dicyclopentadiene Infused Vascular Networks, Giovanni Lewinski

Theses and Dissertations

Self-healing wind turbine blades can reduce costs associated with maintenance, repair, and energy compensation. Self-healing is the ability to sustain and recover from damage autonomously. The self-healing presented in this paper uses the reaction of two agents Dicyclopentadiene, DCPD, and Grubbs’ first-generation catalyst, henceforward known as a catalyst to fuel this recovery. DCPD is housed as a liquid isolated from the catalyst until a damaging event occurs, causing the two agents to mix and solidify to form the thermoset Polydicyclopentadiene, PDCPD. We discuss the efforts made to optimize the self-healing properties of wind turbine blades and provide new systems to …


Model Augmented Deep Neural Networks For Medical Image Reconstruction Problems, Hongquan Zuo Aug 2019

Model Augmented Deep Neural Networks For Medical Image Reconstruction Problems, Hongquan Zuo

Theses and Dissertations

Solving an ill-posed inverse problem is difficult because it doesn't have a unique solution. In practice, for some important inverse problems, the conventional methods, e.g. ordinary least squares and iterative methods, cannot provide a good estimate. For example, for single image super-resolution and CT reconstruction, the results of these conventional methods cannot satisfy the requirements of these applications. While having more computational resources and high-quality data, researchers try to use machine-learning-based methods, especially deep learning to solve these ill-posed problems. In this dissertation, a model augmented recursive neural network is proposed as a general inverse problem method to solve these …


Cybersecurity Education In Utah High Schools: An Analysis And Strategy For Teacher Adoption, Cariana June Cornel Aug 2019

Cybersecurity Education In Utah High Schools: An Analysis And Strategy For Teacher Adoption, Cariana June Cornel

Theses and Dissertations

The IT Education Specialist for the USBE, Brandon Jacobson, stated:I feel there is a deficiency of and therefore a need to teach Cybersecurity.Cybersecurity is the “activity or process, ability or capability, or state whereby information and communications systems and the information contained therein are protected from and/or defended against damage, unauthorized use or modification, or exploitation” (NICE, 2018). Practicing cybersecurity can increase awareness of cybersecurity issues, such as theft of sensitive information. Current efforts, including but not limited to, cybersecurity camps, competitions, college courses, and conferences, have been created to better prepare cyber citizens nationwide for such cybersecurity occurrences. In …


Potential For On-Site, Prosecutorial Evidence From Drug Residues Collected On Plasmonic Paper: A Pilot Study For Sers-Psi-Ms, Daniel S. Burr Jul 2019

Potential For On-Site, Prosecutorial Evidence From Drug Residues Collected On Plasmonic Paper: A Pilot Study For Sers-Psi-Ms, Daniel S. Burr

Theses and Dissertations

Given the potential impact of improvements to on-site drug testing, as well as recent, successful displays of paper spray ionization mass spectrometry (PSI-MS) in this regard, this thesis pilots the implementation of Raman spectroscopy as a compliment to MS for field-based confirmatory drug testing. Surface enhanced Raman scattering (SERS) is utilized for applications to trace detection. Two-tiered analysis of individual drug samples is enabled using triangularly-cut plasmonic papers, from which both SERS and PS-MS analysis may be performed. Several drug compounds, representative of traditional and emerging drug types, are examined by these techniques, both separately and as a fully integrated, …


The Trust-Based Interactive Partially Observable Markov Decision Process, Richard S. Seymour Jun 2019

The Trust-Based Interactive Partially Observable Markov Decision Process, Richard S. Seymour

Theses and Dissertations

Cooperative agent and robot systems are designed so that each is working toward the same common good. The problem is that the software systems are extremely complex and can be subverted by an adversary to either break the system or potentially worse, create sneaky agents who are willing to cooperate when the stakes are low and take selfish, greedy actions when the rewards rise. This research focuses on the ability of a group of agents to reason about the trustworthiness of each other and make decisions about whether to cooperate. A trust-based interactive partially observable Markov decision process (TI-POMDP) is …


Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis May 2019

Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis

Theses and Dissertations

Biofilms are formed when a group of cells of microorganisms stick to each other and often on a surface. The development of biofilm has been a major issue in many fields (medical field, food, chemical, and water industry are a few such fields). In the medical field alone, biofilm infections have reportedly cost over five billion USD in additional healthcare expenses. The food industry usually halts the operation of its plant eight hours, every day to ensure that their equipment and transportation channels are clean and free from any biofilm presence. Similarly, the water and chemical industry need to ensure …


In Situ Chemical Probing Of Vacancy Defects In Graphene And Boron Nitride At Room Temperature, Ali Ihsan Altan May 2019

In Situ Chemical Probing Of Vacancy Defects In Graphene And Boron Nitride At Room Temperature, Ali Ihsan Altan

Theses and Dissertations

IN SITU CHEMICAL PROBING OF VACANCY DEFECTS IN GRAPHENE AND BORON NITRIDE AT ROOM TEMPERATURE

by

Ali Ihsan Altan

The University of Wisconsin-Milwaukee, 2019

Under the Supervision of Professor Jian Chen

Chemical vapor deposition (CVD) has emerged as the most promising technique towards manufacturing of large area, high quality graphene. Characterization, understanding, and controlling of various structural defects in CVD-grown graphene are essential to realize its true potential for real-world applications. We report a new method for in situ chemical probing of vacancy defects in CVD-grown graphene at room temperature. Our approach is based on a solid–gas phase reaction that …


Identifying And Incorporating Driver Behavior Variables Into Crash Prediction Models, Mohammad Razaur Rahman Shaon May 2019

Identifying And Incorporating Driver Behavior Variables Into Crash Prediction Models, Mohammad Razaur Rahman Shaon

Theses and Dissertations

All travelers are exposed to the risk for crashes on the road, as none of the roadways are entirely safe. Under Vision Zero, improving traffic safety on our nation’s highways is and will continue to be one of the most pivotal tasks on the national transportation agenda. For decades, researchers and transportation professionals have strived to identify causal relationships between crash occurrence and roadway geometry, and traffic-related variables on the mission of creating a safe environment for the traveling public. Although great achievements have been witnessed such as the publication of the Highway Safety Manual (HSM), research is rather limited …


The Design And Optimization Of Jet-In-Cross-Flow (Jicf) For Engineering Applications: Thermal Uniformity In Gas-Turbines And Cavitation Treatment In Hydro-Turbines, Tarek Mahmoud Mohammed Elgammal May 2019

The Design And Optimization Of Jet-In-Cross-Flow (Jicf) For Engineering Applications: Thermal Uniformity In Gas-Turbines And Cavitation Treatment In Hydro-Turbines, Tarek Mahmoud Mohammed Elgammal

Theses and Dissertations

Jet-in-cross-flow (JICF) is a well-known term in thermal flows field. Ranging from the normal phenomenon like the volcano ash and dust plumes to the designed film cooling and air fuel mixing for combustion, JICF is always studied to understand its nature at different conditions. Realizing the behavior of interacting flows and importance of many variables lead to the process of reiterating the shapes and running conditions for better outcomes or minimizing the losses. Summarizing the process under the name of optimization, two JICF applications are analyzed based on the principles of thermodynamics and fluid mechanics, then some redesigns are proposed …


Machine Intelligence For Advanced Medical Data Analysis: Manifold Learning Approach, Fereshteh S Bashiri May 2019

Machine Intelligence For Advanced Medical Data Analysis: Manifold Learning Approach, Fereshteh S Bashiri

Theses and Dissertations

In the current work, linear and non-linear manifold learning techniques, specifically Principle Component Analysis (PCA) and Laplacian Eigenmaps, are studied in detail. Their applications in medical image and shape analysis are investigated.

In the first contribution, a manifold learning-based multi-modal image registration technique is developed, which results in a unified intensity system through intensity transformation between the reference and sensed images. The transformation eliminates intensity variations in multi-modal medical scans and hence facilitates employing well-studied mono-modal registration techniques. The method can be used for registering multi-modal images with full and partial data.

Next, a manifold learning-based scale invariant global shape …


Cad-Based Porous Scaffold Design Of Intervertebral Discs In Tissue Engineering, Ye Guo May 2019

Cad-Based Porous Scaffold Design Of Intervertebral Discs In Tissue Engineering, Ye Guo

Theses and Dissertations

With the development and maturity of three-dimensional (3D) printing technology over the past decade, 3D printing has been widely investigated and applied in the field of tissue engineering to repair damaged tissues or organs, such as muscles, skin, and bones, Although a number of automated fabrication methods have been developed to create superior bio-scaffolds with specific surface properties and porosity, the major challenges still focus on how to fabricate 3D natural biodegradable scaffolds that have tailor properties such as intricate architecture, porosity, and interconnectivity in order to provide the needed structural integrity, strength, transport, and ideal microenvironment for cell- and …


Active Polymeric Materials For 3d Shaping And Sensing, Adebola Oyefusi May 2019

Active Polymeric Materials For 3d Shaping And Sensing, Adebola Oyefusi

Theses and Dissertations

Part I: Reprogrammable Chemical 3D Shaping for Origami, Kirigami, and Reconfigurable Molding

Origami- and kirigami-based design principles have recently received strong interest from the scientific and engineering communities because they offer fresh approaches to engineering of structural hierarchy and adaptive functions in materials, which could lead to many promising applications. Herein, we present a reprogrammable 3D chemical shaping strategy for creating a wide variety of stable complex origami and kirigami structures autonomously. This strategy relies on a reverse patterning method that encodes prescribed 3D geometric information as a spatial pattern of the unlocked phase (dispersed phase) in the locked phase …


In Situ Chemical Probing Of Vacancy Defects In Graphene And Boron Nitride At Room Temperature, Ali Ihsan Altan May 2019

In Situ Chemical Probing Of Vacancy Defects In Graphene And Boron Nitride At Room Temperature, Ali Ihsan Altan

Theses and Dissertations

IN SITU CHEMICAL PROBING OF VACANCY DEFECTS IN GRAPHENE AND BORON NITRIDE AT ROOM TEMPERATURE

by

Ali Ihsan Altan

The University of Wisconsin-Milwaukee, 2019

Under the Supervision of Professor Jian Chen

Chemical vapor deposition (CVD) has emerged as the most promising technique towards manufacturing of large area, high quality graphene. Characterization, understanding, and controlling of various structural defects in CVD-grown graphene are essential to realize its true potential for real-world applications. We report a new method for in situ chemical probing of vacancy defects in CVD-grown graphene at room temperature. Our approach is based on a solid–gas phase reaction that …


Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis May 2019

Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis

Theses and Dissertations

Biofilms are formed when a group of cells of microorganisms stick to each other and often on a surface. The development of biofilm has been a major issue in many fields (medical field, food, chemical, and water industry are a few such fields). In the medical field alone, biofilm infections have reportedly cost over five billion USD in additional healthcare expenses. The food industry usually halts the operation of its plant eight hours, every day to ensure that their equipment and transportation channels are clean and free from any biofilm presence. Similarly, the water and chemical industry need to ensure …


Piezoelectric Sensor Crack Detection On Airframe Systems, Kevin J. Lin Mar 2019

Piezoelectric Sensor Crack Detection On Airframe Systems, Kevin J. Lin

Theses and Dissertations

In 2008, the Department of Defense published a guidebook for a methodology named Condition-Based Maintenance Plus (CBM+) which capabilities include improving productivity, shortening maintenance cycles, lowering costs, and increasing availability and reliability. This push replaces existing inspection criteria, often conducted as non-destructive testing (NDT), with structural health monitoring (SHM) systems. The SHM system addressed utilizes guided Lamb waves generated by piezoelectric wafer active sensors (PWAS) to detect the existence, size, and location of damage from through-thickness cracks around a rivet hole. The SHM field lacks an experiment testing how small changes in receiver sensor distances affect damage detection. In addition, …