Digital Commons Network^™

Spare Parts On Demand Using Additive Manufacturing : A Simulation Model For Cost Evaluation., Stefan Jedeck

Electronic Theses and Dissertations

Little is known about the impact of additive manufacturing in the spare part supply chain. A few studies are available, but they focus on specific parts and their applications only. A general model, which can be adapted to different applications, is nonexistent. This dissertation proposes a decision making framework that enables an interested practitioner/manager to decide whether using additive manufacturing to make spare parts on demand is economical when compared to conventional warehousing strategy. The framework consists of two major components: a general discrete event simulation model and a process of designing a wide range of simulation scenarios. The goal …

Heat Transfer Mechanisms In Water-Based Nanofluids., Masoudeh Ahmadi

Electronic Theses and Dissertations

Nanofluids are a class of heat transport fluids created by suspending nano-scaled metallic or nonmetallic particles into a base fluid. Some experimental investigations have revealed that the nanofluids have remarkably higher thermal conductivities than those of conventional pure fluids and are more suited for practical application than the existing techniques of heat transfer enhancement using millimeter and/or micrometer-sized particles in fluids. Use of nanoparticles reduces pressure drop, system wear, and overall mass of the system leading to a reduction in costs over existing enhancement techniques. In this work, the heat transfer coefficient is determined experimentally using copper oxide (CuO) based …

The Effects Of Uncertainty In Engineering Data On The Design And Performance Of Automotive Thermal Systems, Ashley Nicole Lehman

Electronic Theses and Dissertations

This study has two purposes: (1) to investigate the effects of uncertainty on thermal design and performance (2) to establish a process to couple the results from uncertainty analysis with Design for Six Sigma (DFSS) to improve robustness. The research was conducted with support from FCA group. The analysis was applied to a component selected by FCA group; however, it is applicable to any system. The effects of uncertainty were investigated using the Fourier Amplitude Sensitivity Test (FAST). The analysis was run on MATLAB software package using estimated uncertainty ranges for each parameter. The parameters with the greatest influence on …

Supporting Simulation With Training: A Study Of Faculty Perspectives, Joseph Patrick Sweeney

Electronic Theses and Dissertations

Authentic learning is rooted in the idea that learning is situated within a real world context. The learning is then assessed through the performance of a skill or demonstration of applied knowledge (authentic assessment). Using simulation in healthcare education allows students to engage in authentic tasks, and in turn, develop the many skills they need in order to be successful healthcare practitioners. While simulation is not a new concept, advancements in Human Patient Simulators (HPSs) have furthered the possibilities available for the simulation experience, and the use of HPSs continues to grow. Professional development is an important support for undergraduate …

Models And Solutions Algorithms For Improving Operations In Marine Transportation, Maxim A. Dulebenets

Electronic Theses and Dissertations

International seaborne trade rose significantly during the past decades. This created the need to improve efficiency of liner shipping services and marine container terminal operations to meet the growing demand. The objective of this dissertation is to develop simulation and mathematical models that may enhance operations of liner shipping services and marine container terminals, taking into account the main goals of liner shipping companies (e.g., reduce fuel consumption and vessel emissions, ensure on-time arrival to each port of call, provide vessel scheduling strategies that capture sailing time variability, consider variable port handling times, increase profit, etc.) and terminal operators (e.g., …

A Framework For Safety Training Using Virtual Reality Software, Rana Riad

Electronic Theses and Dissertations

Safety training is a vital component to the well-being of individuals in all industries. With technology advancing at the current pace, conventional training methods are no longer the most effective way to communicate information. There is a strong need for safety training that incorporates new methods and forms of communication to obtain higher levels of comprehension. Virtual reality systems offer a highly customizable and interactive form of delivering information to users. This research addresses major gaps in the field of safety training using virtual reality systems and provides a design framework for creating a virtual safety-training system. A model for …

The Impact Of Structured Prebriefing On Nursing Students' Competency Performance, Clinical Judgment And Experience In Simulation, Karin Page-Cutrara

Electronic Theses and Dissertations

AIM To examine the intervention of structured prebriefing, for its effect on students' simulation performance and their prebriefing experience. Prebriefing is the introductory phase of the simulation process.

BACKGROUND Despite its inclusion in the simulation process, little research is available on prebriefing. Reflection theory and concept mapping informed a model-based structured prebriefing activity for preparing students for meaningful learning in simulation.

METHOD A group-randomized, experimental study of 76 baccalaureate nursing students compared competency performance, clinical judgment, and the perception of the prebriefing experience of those receiving structured prebriefing, to those receiving traditional prebriefing activities. The relationship between simulation performance and …

Combustion Kinetics Of Advanced Biofuels, Ghazal Barari

Electronic Theses and Dissertations

Use of biofuels, especially in automotive applications, is a growing trend due to their potential to lower greenhouse gas emissions from combustion. Ketones are a class of biofuel candidates which are produced from cellulose. However, ketones received rather scarce attention from the combustion community compared to other classes such as, alcohols, esters, and ethers. There is little knowledge on their combustion performance and pollutant generation. Hence their combustion chemistry needs to be investigated in detail. Diisopropyl ketone (DIPK) is a promising biofuel candidate, which is produced using endophytic fungal conversion. A detailed understanding of the combustion kinetics of the oxidation …

Modeling Social Norms In Real-World Agent-Based Simulations, Rahmatollah Beheshti

Electronic Theses and Dissertations

Studying and simulating social systems including human groups and societies can be a complex problem. In order to build a model that simulates humans' actions, it is necessary to consider the major factors that affect human behavior. Norms are one of these factors: social norms are the customary rules that govern behavior in groups and societies. Norms are everywhere around us, from the way people handshake or bow to the clothes they wear. They play a large role in determining our behaviors. Studies on norms are much older than the age of computer science, since normative studies have been a …

Information Propagation Algorithms For Consensus Formation In Decentralized Multi-Agent Systems, Christopher Hollander

Electronic Theses and Dissertations

Consensus occurs within a multi-agent system when every agent is in agreement about the value of some particular state. For example, the color of an LED, the position or magnitude of a vector, a rendezvous location, the most recent state of data within a database, or the identity of a leader are all states that agents might need to agree on in order to execute their tasking. The task of the decentralized consensus problem for multi-agent systems is to design an algorithm that enables agents to communicate and exchange information such that, in finite time, agents are able to form …

A New Methodology For Evaluating The Effectiveness Of Bus Rapid Transit Strategies, Ahmad Alomari

Electronic Theses and Dissertations

Over the last few years, public transportation has become more desirable as capacity of existing roadways failed to keep up with rapidly increasing traffic demand. Buses are one of the most common modes of public transportation with low impact on network capacity, especially in small and congested urban areas. However, the use of regularly scheduled buses as the main public transport mode can become useless with the presence of traffic congestion and dense construction areas. In cases like these, innovative solutions, such as bus rapid transit (BRT), can provide an increased level of service without having to resort to other, …

The Effect Of Videogame Play On Robotic Surgery Skill Acquisition, Alyssa Tanaka

Electronic Theses and Dissertations

Robotic surgery uses innovative technology to transcend a surgeon's skills when performing complex procedures. Currently, the only FDA approved robotic system is Intuitive's da Vinci Surgical System. While this system offers many advantages over other minimally invasive techniques, it also introduces a need for specialized training. Virtual reality simulators have emerged as valuable tools for standardized and objective robotic surgery skill training and assessments. In recent years, the idea of using video game technology in surgical education for laparoscopy has also been explored; however few have attempted to make a connection between video game experience and robotic surgical skills. Thus, …

Data-Driven Simulation Modeling Of Construction And Infrastructure Operations Using Process Knowledge Discovery, Reza Akhavian

Electronic Theses and Dissertations

Within the architecture, engineering, and construction (AEC) domain, simulation modeling is mainly used to facilitate decision-making by enabling the assessment of different operational plans and resource arrangements, that are otherwise difficult (if not impossible), expensive, or time consuming to be evaluated in real world settings. The accuracy of such models directly affects their reliability to serve as a basis for important decisions such as project completion time estimation and resource allocation. Compared to other industries, this is particularly important in construction and infrastructure projects due to the high resource costs and the societal impacts of these projects. Discrete event simulation …

Integrated Maritime Simulation Complex Management, Quality And Training Effectiveness From The Perspective Of Modeling And Simulation In The State Of Florida, Usa (A Case Study), Yaser Sendi

Electronic Theses and Dissertations

Naturally, maritime training simulators at all events are valuable instructional and pedagogical tools. Through the history, the maritime simulation was utilized to train prospective maritime apprentices in whom it has filled the gap left by the acute shortage of opportunities for jobs onboard vessels around the globe. However, professional seafarers are the axis of success and competitiveness in the field of maritime training. They are the ones that, who are well trained and have the responsibilities of their work and the surrounding environment. In order to achieve the success along with effective training skills, both maritime companies and seafarers should …

A Generic Framework For Multi-Method Modeling And Simulation Of Complex Systems Using Discrete Event, System Dynamics And Agent Based Approaches., Konstantinos Mykoniatis

Electronic Theses and Dissertations

Decisions about Modeling and Simulation (M&S) of Complex Systems (CS) need to be evaluated prior to implementation. Discrete Event (DE), System Dynamics (SD), and Agent Based (AB) are three different M&S approaches widely applied to enhance decision-making of complex systems. However, single type M&S approaches can face serious challenges in representing the overall multidimensional nature of CS and may result in the design of oversimplified models excluding important factors. Conceptual frameworks are necessary to offer useful guidance for combining and/or integrating different M&S approaches. Although several hybrid M&S frameworks have been described and are currently deployed, there is limited guidance …