Engineering Commons^™

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 …

A Systematic Approach For Automatically Answering General-Purpose Objective And Subjective Questions, Lok Prasad Acharya

Theses and Dissertations

In this era of information explosion, people generally rely on the Internet, and more precisely, the search engines to get answers to their questions. However, what a search engine can do is just retrieve documents. Given some keywords, it only returns the relevant ranked documents that contain the keywords. Although users often want a precise answer to a question, they are left to extract answers from the documents themselves. This is where Automatic Question Answering (AQA) systems come into play. An AQA system takes questions in natural language as input and searches related answers in the set of documents and …

Effects Of Resampled Data On Time Series Forecasting Accuracy, Jennifer Garland

Theses and Dissertations

This thesis will look at time series forecasting of the air pollutants in Beijing, China and the power consumption of an individual household located in Sceaux, France. The forecast will be taken from two classical methods, the Holt-Winters’ methods and the Seasonal Autoregressive Integrated Moving Average (SARIMA) method. The Holt-Winters’ method will be looked at from the additive, multiplicative and damped methods. The SARIMA model will be looked at as a uni-variate model. In this thesis, it will be shown that less complex algorithms, such as the Holt-Winters’ methods can process larger data sets without the need of resampling, and …

Improving Grapheme-To-Phoneme Translation With The Use Of Nalu Attention Mechanisms, Brian Sheldon Smith

Theses and Dissertations

In recent years, Natural Language Processing in the field of machine learning has seen some major improvements. Data scientists have shown that neural networks are capable of breaking down semantics of sentences, translating languages, and answering complex questions with fast recall. While impressive, these feats all hinge on having access to a massive amount of clean text, or data sets with almost perfect grammar and spelling. Without this, neural networks will usually fail to converge on a meaningful result. To partially this dependency, Grapheme-to-Phoneme conversion can be employed. This is the conversion of words from their spellings to a form …

Deep Learning Models For Visibility Forecasting, Luz Carolina Ortega Gomez

Theses and Dissertations

This dissertation addresses the task of visibility forecasting via deep learning models using data from weather stations. Visibility is one of the most critical weather impacts on transportation systems. Low visibility conditions can seriously impact safety and traffic operations, leading to adverse scenarios, causing accidents, and jeopardizing transportation systems. Accurate visibility forecasting plays a key role in decision-making and management of transportation systems. However, due to the complexity and variability of weather variables, visibility forecasting remains a highly challenging task and a matter of significant interest for transportation agencies nationwide. This dissertation explores the use of deep learning models for …

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 …

A Data-Driven Predictive Model Of Reliability Estimation Using State-Space Stochastic Degradation Model, Farhad Balali

Theses and Dissertations

The concept of the Industrial Internet of Things (IIoT) provides the foundation to apply data-driven methodologies. The data-driven predictive models of reliability estimation can become a major tool in increasing the life of assets, lowering capital cost, and reducing operating and maintenance costs. Classical models of reliability assessment mainly rely on lifetime data. Failure data may not be easily obtainable for highly reliable assets. Furthermore, the collected historical lifetime data may not be able to accurately describe the behavior of the asset in a unique application or environment. Therefore, it is not an optimal approach anymore to conduct a reliability …

Dynamic Vehicular Trajectory Optimization For Bottleneck Mitigation And Safety Improvement, Wenqing Chen

Theses and Dissertations

Traffic bottleneck is defined as a disruption of traffic flow through a freeway or an arterial, which can be divided as two categories: stationary bottleneck and moving bottleneck. The stationary bottleneck is mainly formed by the lane drops in the multi-lane roadways, while the moving bottleneck are due to the very slowing moving vehicles which disrupt the traffic flow. Traffic bottlenecks not only impact the mobility, but also potentially cause safety issues.

Traditional strategies for eliminating bottlenecks mainly focus on expanding supply including road widening, green interval lengthening and optimization of intersection channelization. In addition, a few macroscopic methods are …

Uncertainty And Error In Combat Modeling, Simulation, And Analysis, Jason A. Blake

Theses and Dissertations

Due to the infrequent and competitive nature of combat, several challenges present themselves when developing a predictive simulation. First, there is limited data with which to validate such analysis tools. Secondly, there are many aspects of combat modeling that are highly uncertain and not knowable. This research develops a comprehensive set of techniques for the treatment of uncertainty and error in combat modeling and simulation analysis. First, Evidence Theory is demonstrated as a framework for representing epistemic uncertainty in combat modeling output. Next, a novel method for sensitivity analysis of uncertainty in Evidence Theory is developed. This sensitivity analysis method …

Two Essays On Distribution, Fulfillment And Pricing Decisions For Retailers With E-Commerce Channel, Khosro Pichka

Theses and Dissertations

E-commerce has grown rapidly in the past decade. In 2015, e-commerce was accounted for 7.2 percent of all retail sales in the U.S., which is massively higher than 0.2 percent in 1998 (U.S. Department of Commerce 2017). Worldwide e-commerce sales also show the same trend and reached $2.356 trillion in 2018 and are expected to grow steadily (Statista 2017). This trend has impacted major areas of operations management including supply chain management and revenue management. Today, e-commerce companies cannot satisfy their customers’ demand using traditional distribution systems. Therefore, retailers with e-commerce channels (e-tailers), cooperate with third party logistic service providers …

Development Of Cislunar Space Logistics Networks For Satellite Constellation Support Using Event-Driven Generalized Multi-Commodity Network Flows, Alexander R. Collins

Theses and Dissertations

As space becomes an increasingly congested domain, the risk of damage to satellite constellations is increasing. In response, there is an increasing need for capabilities for unmanned repair, refueling, and reconstitution (R3) of those constellations. Cislunar orbits offer a promising storage and low-cost transfer solution for on-orbit service vehicles and replacement satellites to leverage those capabilities. This research makes use of mixed-integer linear programming-based logistics models to determine the situations in which a cislunar mission architecture would offer a cost-effective alternative to Earth-based R3. The network models presented in this research make use of the latest developments in Event-Driven Generalized …

Operational Decision Making Under Uncertainty: Inferential, Sequential, And Adversarial Approaches, Andrew J. Keith

Theses and Dissertations

Modern security threats are characterized by a stochastic, dynamic, partially observable, and ambiguous operational environment. This dissertation addresses such complex security threats using operations research techniques for decision making under uncertainty in operations planning, analysis, and assessment. First, this research develops a new method for robust queue inference with partially observable, stochastic arrival and departure times, motivated by cybersecurity and terrorism applications. In the dynamic setting, this work develops a new variant of Markov decision processes and an algorithm for robust information collection in dynamic, partially observable and ambiguous environments, with an application to a cybersecurity detection problem. In the …

Equilibrium Modeling And Policy Analysis Of A Biofuel Supply Chain With A Hydroelectric Reservoir, Jinwoo Bae

Theses and Dissertations

This research proposesd a game theoretic model of a biofuel supply chain (BSC) where a utility company supplies reservoir water to two farmers, located in downstream and upstream of a hydropower dam. The decision-making process of the model is formulated as a three-stage Stackelberg game. We analyze the equilibrium of the decentralized systems and the effect of the government subsidy on energy crop (switchgrass) production for cellulosic biofuel industries, with two forms of subsidy: (1) discriminated subsidies and (2) equalized subsidies.

The results show that both forms of subsidy improve social welfare in the BSC unless the amount of subsidy …

Analysis Of Pile Driving Monitoring Equipment, Robert Joseph Rogulski Iii

Theses and Dissertations

Rebound is a problem affecting pile driving in Florida. Significant rebound can require excessive blows for a pile to reach bearing capacity and may damage the pile. In order to study rebound, precise instrumentation is required. For that reason, the objective of this thesis is to evaluate the Inopile’s Pile Driving Monitor (PDM) as a tool for measuring the rebound of large diameter pre-stressed concrete piles driven with open ended diesel hammers. Six sites from Florida were selected for testing. Five of the sites had pile driving and two of them had standard penetration testing (which was used as an …

Persuasion, Political Warfare, And Deterrence: Behavioral And Behaviorally Robust Models, William N. Caballero

Theses and Dissertations

This dissertation examines game theory models in the context of persuasion and competition wherein decision-makers are not completely rational by considering two complementary threads of research. The first thread of research pertains to offensive and preemptively defensive behavioral models. Research in this thread makes three notable contributions. First, an offensive modeling framework is created to identify how an entity optimally influences a populace to take a desired course of action. Second, a defensive modeling framework is defined wherein a regulating entity takes action to bound the behavior of multiple adversaries simultaneously attempting to persuade a group of decision-makers. Third, an …

Application Of The Gradient Projection Method To An Optimal Control Problem In Quantum Biology, Rashad Abdulla

Theses and Dissertations

Quantum biology is an emerging field which seeks to understand and analyze the effects of quantum mechanical phenomena on biological systems. One such phenomenon is the formation of radical pairs, compounds which exist in a quantum superposition of two states until they collapse into one or the other. The probability of the collapse into a preferred state can be calculated from the Schrödinger equation, and is in fact dependent on external magnetic fields. This project utilizes principles of mathematical optimal control and quantum biology to determine the precise sequence of magnetic field pulses that maximize the probability of achieving the …

Using Pythagorean Fuzzy Sets (Pfs) In Multiple Criteria Group Decision Making (Mcgdm) Methods For Engineering Materials Selection Applications, Alaa Fouad Momena

Theses and Dissertations

The process of materials’ selection is very critical during the initial stages of designing manufactured products. Inefficient decision-making outcomes in the material selection process could result in poor quality of products and unnecessary costs. In the last century, numerous materials have been developed for manufacturing mechanical components in different industries. Many of these new materials are similar in their properties and performances, thus creating great challenges for designers and engineers to make accurate selections. Our main objective in this work is to assist decision makers (DMs) within the manufacturing field to evaluate materials alternatives and to select the best alternative …

A Hierarchical, Fuzzy Inference Approach To Data Filtration And Feature Prioritization In The Connected Manufacturing Enterprise, Phillip Matthew Lacasse

Theses and Dissertations

The current big data landscape is one such that the technology and capability to capture and storage of data has preceded and outpaced the corresponding capability to analyze and interpret it. This has led naturally to the development of elegant and powerful algorithms for data mining, machine learning, and artificial intelligence to harness the potential of the big data environment. A competing reality, however, is that limitations exist in how and to what extent human beings can process complex information. The convergence of these realities is a tension between the technical sophistication or elegance of a solution and its transparency …

Fracture Toughness And Fatigue Crack Growth Rate Characterization Of Inconel 718 Formed By Laser Powder Bed Fusion, Charles C. Hohnbaum

Theses and Dissertations

Continuing improvement in the field of AM of metals provides the opportunity for direct fabrication of aerospace parts. AM was once used in large part for rapid prototyping but improvements in technology and increases in the knowledge base of AM materials has provided the opportunity for manufacture of AM parts for operational use. The ability to create low numbers of unique parts without having to invest in expensive tooling provides great economic incentive to utilize this technique. IN718 is the most common high temperature alloy used in the aerospace industry and lends itself readily to formation by LPBF. The superior …

Search And Rescue Operations Forecasting And Optimization, Zachary T. Hornberger

Theses and Dissertations

United States Coast Guard District 14 is responsible for the execution of eleven statutory missions across the Pacific region. Despite having the largest geographic area of responsibility (AOR), District 14 has command of among the fewest resources to accomplish these missions. When search and rescue (SAR) emergencies occur, these events take immediate priority because the ability to rapidly coordinate available assets can be the difference between saving or losing a life. Using historic records of SAR incidents for District 14, we leverage an approach called the stochastic zonal distribution model to evaluate spatiotemporal trends in emergency rates and response strategies …

Group Decision-Making, Edward Cook

Theses and Dissertations

The present work explores improvements in group decision-making. It begins with a practical example using state-of-the-art techniques for a complex, high-risk decision. We show how these techniques can reveal a better alternative. Although we created an improved decision process, decision-makers were apt to protect their own organizations instead of the project. This tendency was reduced over the course of the decision-making process but inspired the first conceptual component of this work.

The first concept describes the “Cost of Conflict” that can arise in a group decision, using game theory to represent the non-cooperative approach and comparing the outcome to the …

Material Interactions And Self-Assembly In Inkjet Printing, Karam Nashwan Al-Milaji

Theses and Dissertations

Inkjet printing has attracted much attention in recent years as a versatile manufacturing tool, suitable for printing functional materials. This facile, low-cost printing technique with high throughput and accuracy is considered promising for a wide range of applications including but not limited to optical and electronic devices, sensors, solar cells, biochips, and displays. The performance of such functional devices is significantly influenced by the deposit morphology and printing resolution. Therefore, fabrication functional devices with precise footprints by inkjet printing requires deep understanding of ink properties, material interactions, and material self-assembly.

In conventional inkjet printing process, where sessile droplets are directly …