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Operations Research, Systems Engineering and Industrial Engineering
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- Systems engineering (5)
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- Bi-objective optimization (2)
- Case study (2)
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- Control chart pattern recognition (2)
- Daniel Felix Ritchie School of Engineering and Computer Science (2)
- Data mining (2)
- Decision Making (2)
- Demand response (2)
Articles 31 - 60 of 261
Full-Text Articles in Engineering
Mathematical Models And Analysis For Demand Side Management In Residential Electricity Distribution Networks., Arnab Roy
Electronic Theses and Dissertations
Development of smart grids along with communication technologies have led to the increased attention and adoption of demand side management (DSM) in the residential sector. Among various DSM schemes, demand response (DR) is a market- based mechanism to shave peak electricity consumption at the system level. In the past decade, the academia has seen a growing literature studying load management methodologies for residential consumers. A typical demand response program has three important facets: the energy cost, comfort of the consumers and overall system efficiency. In this dissertation, we investigate and develop models for effective load control to minimize energy cost …
Determining The Efficacy Of Additive Manufacturing For The Aerospace Spare Parts Supply Chain, Kyle O'Brien
Determining The Efficacy Of Additive Manufacturing For The Aerospace Spare Parts Supply Chain, Kyle O'Brien
Electronic Theses and Dissertations
This thesis investigates how additive manufacturing (AM) based on-demand part production can supplement or replace the traditional production and inventory in typical aerospace’s spare parts supply chain systems. This study focuses on the operational characteristics of AM and its impacts on the overall logistics of plant-level operations. To capture the microscopic operational aspects of the AM production, a discrete-event simulation based approach was adopted, with key AM operation resources (e.g. AM system, operator) and attributes (e.g. AM manufacturing speed, individual part characteristics and demands) accounted for in the modeling process. In addition, a benchmark warehouse inventory model was also established …
A Machine Learning Approach For Allocating Route Cost To Customers For Transportation And Logistics Services., Alison Davis
A Machine Learning Approach For Allocating Route Cost To Customers For Transportation And Logistics Services., Alison Davis
Electronic Theses and Dissertations
Advancements in big data enabled management practices inspire logistics companies to study deeper into their transportation operations with a data driven approach. One such question asks: How can a logistics firm identify high-cost customers in their service network? In the presence of rich data on routes involving many customers, this thesis develops a framework to allocate a route cost among customers that the route serves, where each route is associated with multiple route features related to the transportation cost. Cost is allocated using the proportional allocation approach in combination with the random forest method in machine learning. First, this framework …
Optimization And Simulation Models To Improve Access To Organ Transplantation In The United States., Fatemeh Karami
Optimization And Simulation Models To Improve Access To Organ Transplantation In The United States., Fatemeh Karami
Electronic Theses and Dissertations
Organ allocation in the U.S. is administrated by the United Network of Organ Sharing (UNOS). UNOS’s mission is to ensure fair and equitable allocation of organs as stated in the Code of Federal Regulations, which reads "neither place of residence nor place of listing shall be a major determinant of access to transplant". Despite the regulations, there has been endless controversy surrounding the disparity in access to organ transplants. In this context, the primary research goal in this dissertation was to reduce geographic disparity in access to transplants in the U.S., with a focus on heart and kidney transplants. To …
Effects Of Design Autonomy On The Flow Experience, Antonio F Coriano
Effects Of Design Autonomy On The Flow Experience, Antonio F Coriano
Electronic Theses and Dissertations
Most modern workplace settings are laden with operating procedures aimed at standardizing action in the name of efficiency. The cost of this standardization is the autonomy of the operator. Mihaly Csikszentmihalyi stated the problem concisely in his 1975 work Beyond Boredom and Anxiety “… [M]ost of the institutions that take up our time…are organized around the assumption that serious work is grim and unpleasant. Because of this assumption, most of our time is spent doing unpleasant things”. An experiment was created to study and better understand how to redress this harmful situation. Sixteen subjects were given a SolidWorks computer-aided design …
Joint Location And Inventory Models And Algorithms For Deployment Of Hybrid Electric Vehicle Charging Stations., Jie Zhang
Electronic Theses and Dissertations
This thesis describes a study of a novel concept of hybrid electric vehicle charging stations in which two types of services are offered: battery swapping and fast level-3 DC charging. The battery swapping and fast-charging service are modeled by using the M/G/s/s model and the M/G/s/$\infty$ model, respectively. In particular, we focus on the operations of joint battery swapping and fast charging services, develop four joint locations and inventory models: two for the deployment of battery swapping service, two for the deployment of hybrid electric vehicle charging service. The first model for each deployment system considers a service-level constraint for …
Gridhub: A Grid-Based, High-Density Material Handling System., Gang Hao
Gridhub: A Grid-Based, High-Density Material Handling System., Gang Hao
Electronic Theses and Dissertations
In the past twenty years, the share of e-commerce has increased (FRED, 2019). Since more and more activities, such as picking and sorting customers’ orders, are done in warehouses, high efficiency warehouses are in demand. Furthermore, the efficiency of warehouses is related to customer satisfaction (Colla and Lapoule, 2012). Storage systems are key components in warehouses, which are related to the efficiency of warehouse operations. In this dissertation, we address an automatic puzzle-based storage system under decentralized control. We call this system GridHub. GridHub meets standards of Industry 4.0 (Lasi et al., 2014), and it features high throughput with parallel …
Investigating The Feasibility, Procedures, Benefits, And Challenges Of Using Mixed Reality In Construction Projects: An Electrical Layout Case Study, Samjhana Shakya
Investigating The Feasibility, Procedures, Benefits, And Challenges Of Using Mixed Reality In Construction Projects: An Electrical Layout Case Study, Samjhana Shakya
Electronic Theses and Dissertations
Innovation and development of technology in the field of visualization have affected the way of designing, presenting, and interacting of the design in the architecture and construction industry. With the invention of the Mixed Reality (MR) device, HoloLens, 2016, many researchers and construction practitioners have marched their research of implementing the MR application in the construction industry. However, there is scarce research on the MR application review, the workflow of using BIM models with the HoloLens, its implementation in the site, and the benefits and challenges of the MR application in the construction site. The gap in the research needs …
Simulation And Optimization Of A Multi-Agent System On Physical Internet Enabled Interconnected Urban Logistics., Long Zheng
Electronic Theses and Dissertations
An urban logistics system is composed of multiple agents, e.g., shippers, carriers, and distribution centers, etc., and multi-modal networks. The structure of Physical Internet (PI) transportation network is different from current logistics practices, and simulation can effectively model a series of PI-approach scenarios. In addition to the baseline model, three more scenarios are enacted based on different characteristics: shared trucks, shared hubs, and shared flows with other less-than-truckload shipments passing through the urban area. Five performance measures, i.e., truck distance per container, mean truck time per container, lead time, CO2 emissions, and transport mean fill rate, are included in …
Aisle Design For Order Picking Operations With Unit-Load Replenishment., Dominic Ian Sleigh
Aisle Design For Order Picking Operations With Unit-Load Replenishment., Dominic Ian Sleigh
Electronic Theses and Dissertations
The warehouse design problem has been addressed in the last decade with fewer constraints than ever before. Between optimization for unit load and order picking warehouses, the former has had extensively more research performed. Unit load optimization efforts have promised labor savings of 20-22%. Of the existing research for order-picking warehouses, only small improvements of less than 4% have been claimed. We propose the design optimization for order-picking warehouses requires consideration for inherently incurred unit load operations from pallet inbound activities, as well as forward-pick area replenishment. We perform experiments comparing optimization of aisle design using order picking data with …
A Study Of Nonlinear Dynamics Of Eeg Responses To Simulated Unmanned Vehicle Tasks, Ziqing Xu
A Study Of Nonlinear Dynamics Of Eeg Responses To Simulated Unmanned Vehicle Tasks, Ziqing Xu
Electronic Theses and Dissertations
In the contemporary world, mental workload becomes higher as technology evolves and task demand becomes overwhelming. The operators of a system are usually required to complete tasks with higher complicity within a shorter period of time. Continuous operation under a high level of mental workload can be a major source of risk and human error, thus put the operator in a hazardous working environment. Therefore, it is necessary to monitor and assess mental workload. In this study, an unmanned vehicle operation with visual detection tasks was investigated by means of nonlinear analysis of EEG time series. Nonlinear analysis is considered …
Hybrid Life Cycle Sustainability Assessment-Based Multi-Objective Optimization: A Case For Sustainable Fleet Mix, Burak Sen
Electronic Theses and Dissertations
Sustainable transportation idea includes not only switching from conventional energy sources to alternative fuel resources, but also diverging from private vehicle use and shifting to alternative transportation modes. As a part of alternative transportation mode, utilizing alternative fuels in public transportation operation supports sustainable transportation at it full-glance. Given their implications in terms of air quality and sustainable movement of people, transit buses, which provide the primary public transportation service, are considered an ideal domain for the deployment of alternative fuels. An input-output (IO) model is developed based on Eora database – a detailed IO database that consists of national …
A Two-Stage Approach To Ridesharing Assignment And Auction In A Crowdsourcing Collaborative Transportation Platform., Peiyu Luo
Electronic Theses and Dissertations
Collaborative transportation platforms have emerged as an innovative way for firms and individuals to meet their transportation needs through using services from external profit-seeking drivers. A number of collaborative transportation platforms (such as Uber, Lyft, and MyDHL) arise to facilitate such delivery requests in recent years. A particular collaborative transportation platform usually provides a two sided marketplace with one set of members (service seekers or passengers) posting tasks, and the another set of members (service providers or drivers) accepting on these tasks and providing services. As the collaborative transportation platform attracts more service seekers and providers, the number of open …
Maximizing Space Utilization In Unit-Load Warehouses., Luis Felipe Cardona Olarte
Maximizing Space Utilization In Unit-Load Warehouses., Luis Felipe Cardona Olarte
Electronic Theses and Dissertations
In a unit-load warehouse, products are stored and retrieved in pallet quantities. Examples include retail distribution centers (DC), third-party DCs, and transshipment hubs in freight transportation. Expenses related to space are a significant component of the operational cost of unit-load warehouses; therefore, maximizing space utilization is important. Moreover, the continuing revolution of retail e-commerce is changing the role and design of modern distribution centers (Boysen et al., 2018). An important trend with serious implications for design is the desire of many distributors to locate DCs in or near metropolitan areas in order to support same-day service or better (Thuermer, 2018). …
A Framework To Develop Anomaly Detection/Fault Isolation Architecture Using System Engineering Principles, Thomas Clark
A Framework To Develop Anomaly Detection/Fault Isolation Architecture Using System Engineering Principles, Thomas Clark
Electronic Theses and Dissertations
For critical systems, timely recognition of an anomalous condition immediately starts the evaluation process. For complex systems, isolating the fault to a component or subsystem results in corrective action sooner so that undesired consequences may be minimized. There are many unique anomaly detection and fault isolation capabilities available with innovative techniques to quickly discover an issue and identify the underlying problems. This research develops a framework to aid in the selection of appropriate anomaly detection and fault isolation technology to augment a given system. To optimize this process, the framework employs a model based systems engineering approach. Specifically, a SysML …
A Methodology For Data-Driven Decision-Making In Last Mile Delivery Operations, Edgar Gutierrez Franco
A Methodology For Data-Driven Decision-Making In Last Mile Delivery Operations, Edgar Gutierrez Franco
Electronic Theses and Dissertations
Across all industries, from manufacturing to services, decision-makers must deal day to day with the outcomes from past and current decisions that affect their business. Last-mile delivery is the term used in supply chain management to describe the movement of goods from a hub to final destinations. This research proposes a methodology that supports decision making for the execution of last-mile delivery operations in a supply chain. This methodology offers diverse, hybrid, and complementary techniques (e.g., optimization, simulation, machine learning, and geographic information systems) to understand last-mile delivery operations through data-driven decision-making. The hybrid modeling might create better warning systems …
The Challenges And Barriers To Employment For Female In Riyadh And Tabuk, Sultan Almutairi
The Challenges And Barriers To Employment For Female In Riyadh And Tabuk, Sultan Almutairi
Electronic Theses and Dissertations
Women labor force participation plays an important role in economic. The developing in economy in Saudi Arabia depends on men rather than women, more than 50 years the Saudi women participation in the labor force extremely is low, this dissertation seeks to identify the challenges and barriers to employment for women in Riyadh and Tabuk. This study examines three research questions. The first question explored the difference between the rate of women unemployment in Tabuk and the rate of women unemployment in Riyadh. The second question investigated ways in which a logistic regression using demographics data could be used to …
The Challenges And Barriers Facing Successful Lean Implementation In The Qatari Manufacturing Organizations, Abdulwahab Alyousef
The Challenges And Barriers Facing Successful Lean Implementation In The Qatari Manufacturing Organizations, Abdulwahab Alyousef
Electronic Theses and Dissertations
The success of Toyota, the inventor of Lean Systems has drawn the attention of academics, researchers, and executives in the last decades. However, existing lean research is largely focused on developed economies in Europe, the Americas, and in Southeast Asia with little focus on the Arab world in general and Qatar specifically. There has been an emergence of manufacturing organizations and Small and Medium- sized Enterprises (SME) in Qatar recently which was the focus of this research. Despite the many attempts to implement lean in organizations, there have been a large number of failed attempts. This research aims to study …
Stochastic Optimization And Applications With Endogenous Uncertainties Via Discrete Choice Models, Mengnan Chen
Stochastic Optimization And Applications With Endogenous Uncertainties Via Discrete Choice Models, Mengnan Chen
Electronic Theses and Dissertations
Stochastic optimization is an optimization method that solves stochastic problems for minimizing or maximizing an objective function when there is randomness in the optimization process. In this dissertation, various stochastic optimization problems from the areas of Manufacturing, Health care, and Information Cascade are investigated in networks systems. These stochastic optimization problems aim to make plan for using existing resources to improve production efficiency, customer satisfaction, and information influence within limitation. Since the strategies are made for future planning, there are environmental uncertainties in the network systems. Sometimes, the environment may be changed due to the action of the decision maker. …
A Study Of Perceptions On Incident Response Exercises, Information Sharing, Situational Awareness, And Incident Response Planning In Power Grid Utilities, Joseph Garmon
Electronic Theses and Dissertations
The power grid is facing increasing risks from a cybersecurity attack. Attacks that shut off electricity in Ukraine have already occurred, and successful compromises of the power grid that did not shut off electricity to customers have been privately disclosed in North America. The objective of this study is to identify how perceptions of various factors emphasized in the electric sector affect incident response planning. Methods used include a survey of 229 power grid personnel and the use of partial least squares structural equation modeling to identify causal relationships. This study reveals the relationships between perceptions by personnel responsible for …
Multi-Level Optimization With Pricing Strategy Under Boundedly Rationality User Equilibrium, Guanxiang Yun
Multi-Level Optimization With Pricing Strategy Under Boundedly Rationality User Equilibrium, Guanxiang Yun
Electronic Theses and Dissertations
We study multi-level optimization problem on energy system, transportation system and information network. We use the concept of boundedly rational user equilibrium (BRUE) to predict the behaviour of users in systems. By using multi-level optimization method with BRUE, we can help to operate the system work in a more efficient way. Based on the introducing of model with BRUE constraints, it will lead to the uncertainty to the optimization model. We generate the robust optimization as the multi-level optimization model to consider for the pessimistic condition with uncertainty. This dissertation mainly includes four projects. Three of them use the pricing …
Factors Affecting Systems Engineering Rigor In Launch Vehicle Organizations, Denton Gibson
Factors Affecting Systems Engineering Rigor In Launch Vehicle Organizations, Denton Gibson
Electronic Theses and Dissertations
Systems engineering is a methodical multi-disciplinary approach to design, build, and operate complex systems. Launch vehicles are considered by many extremely complex systems that have greatly impacted where the systems engineering industry is today. Launch vehicles are used to transport payloads from the ground to a location in space. Satellites launched by launch vehicles can range from commercial communications to national security payloads. Satellite costs can range from a few million dollars to billions of dollars. Prior research suggests that lack of systems engineering rigor as one of the leading contributors to launch vehicle failures. A launch vehicle failure could …
Methods For Online Feature Selection For Classification Problems, Alaleh Razmjoo
Methods For Online Feature Selection For Classification Problems, Alaleh Razmjoo
Electronic Theses and Dissertations
Online learning is a growing branch of machine learning which allows all traditional data mining techniques to be applied on an online stream of data in real-time. In this dissertation, we present three efficient algorithms for feature ranking in online classification problems. Each of the methods are tailored to work well with different types of classification tasks and have different advantages. The reason for this variety of algorithms is that like other machine learning solutions, there is usually no algorithm which works well for all types of tasks. The first method, is an online sensitivity based feature ranking (SFR) which …
Modeling The Innovation Ecosystem And Development Of A Dynamic Innovation Index, Henriette Schoen
Modeling The Innovation Ecosystem And Development Of A Dynamic Innovation Index, Henriette Schoen
Electronic Theses and Dissertations
The topic of innovation currently generates a tremendous amount of interest around the world. Innovation is considered an essential part of the solution to creating more jobs and improving the socio-economic conditions of many countries around the globe. Innovation comes about through the existence of many interrelated solutions to socio-economic problems in an extensively interconnected network, which create value for each other. Such a complex creativity and innovation value-creating network is here called an Innovation Ecosystem (IE). The main objective of this dissertation research is to improve the current understanding of the IE by developing a simulation model that uses …
Developing Optimization Techniques For Logistical Tendering Using Reverse Combinatorial Auctions, Jennifer Kiser
Developing Optimization Techniques For Logistical Tendering Using Reverse Combinatorial Auctions, Jennifer Kiser
Electronic Theses and Dissertations
In business-to-business logistical sourcing events, companies regularly use a bidding process known as tendering in the procurement of transportation services from third-party providers. Usually in the form of an auction involving a single buyer and one or more sellers, the buyer must make decisions regarding with which suppliers to partner and how to distribute the transportation lanes and volume among its suppliers; this is equivalent to solving the optimization problem commonly referred to as the Winner Determination Problem. In order to take into account the complexities inherent to the procurement problem, such as considering a supplier’s network, economies of scope, …
Binder Jetting Additive Manufacturing Process Fundamentals And The Resultant Influences On Part Quality., Hadi Miyanaji
Binder Jetting Additive Manufacturing Process Fundamentals And The Resultant Influences On Part Quality., Hadi Miyanaji
Electronic Theses and Dissertations
Binder jetting additive manufacturing (BJ-AM) technology is a process by which a part is fabricated layer by layer through depositing liquid binder in the designated regions of each layer until the feature is complete. Due to the use of binder in geometry generation, this process possesses various advantages over the other additive manufacturing technologies including the ability to create colored objects via colored binders, lower cost, lack of heat-induced defects, and its potential capability to print a variety of materials such as metals, sands and ceramics. Although the application of the binder jetting process has been recently reported by different …
Solving School Bus Routing And Student Assignment Problems With Heuristic And Column Generation Approach., Di Zhang
Electronic Theses and Dissertations
In this dissertation, we solve a school bus routing problem of transporting students including special education (handicapped) students and assigning them in Oldham county education district. The main contribution of this research is that we consider special education students (Type-2) along with other students (Type-1) and design a comprehensive school bus schedule to transport both kinds of students at the same time. Also, a student assignment mathematical model is presented to optimize the number of bus stops in use as well as one important measure of service quality, the total student walking distance. Comparing to the classic clustering methods, heuristic …
Tooling For Injection Molding Using Laser-Powder Bed Fusion., Mohith Ram Buxani
Tooling For Injection Molding Using Laser-Powder Bed Fusion., Mohith Ram Buxani
Electronic Theses and Dissertations
Laser-Powder Bed Fusion (L-PBF) has been considered for some time by the injection molding industry for the fabrication of tooling for injection molding in order to address large lead times and costs for tool-making. Computer-aided simulations are also routinely used to evaluate new part and mold designs as well as understanding the effects of material compositions and processing conditions on part quality and overall productivity. However, there remains a significant need to integrate the perspectives from injection molding, 3D printing, metal powders, and component design and process simulation to better utilize LPBF for fabricating tooling required for injection molding. The …
An Agent Based Model To Assess Crew Temporal Variability During U.S. Navy Shipboard Operations, Kevin Muhs
An Agent Based Model To Assess Crew Temporal Variability During U.S. Navy Shipboard Operations, Kevin Muhs
Electronic Theses and Dissertations
Understanding the factors that affect human performance variability as well as their temporal impacts is an essential element in fully integrating and designing complex, adaptive environments. This understanding is particularly necessary for high stakes, time-critical routines such as those performed during nuclear reactor, air traffic control, and military operations. Over the last three decades significant efforts have emerged to demonstrate and apply a host of techniques to include Discrete Event Simulation, Bayesian Belief Networks, Neural Networks, and a multitude of existing software applications to provide relevant assessments of human task performance and temporal variability. The objective of this research was …
Ultrasonic Nondestructive Evaluation Of Metal Additive Manufacturing., Venkata Karthik Nadimpalli
Ultrasonic Nondestructive Evaluation Of Metal Additive Manufacturing., Venkata Karthik Nadimpalli
Electronic Theses and Dissertations
Metal Additive Manufacturing (AM) is increasingly being used to make functional components. One of the barriers for AM components to become mainstream is the difficulty to certify them. AM components can have widely different properties based on process parameters. Improving an AM processes requires an understanding of process-structure-property correlations, which can be gathered in-situ and post-process through nondestructive and destructive methods. In this study, two metal AM processes were studied, the first is Ultrasonic Additive Manufacturing (UAM) and the second is Laser Powder Bed Fusion (L-PBF). The typical problems with UAM components are inter-layer and inter-track defects. To improve the …