Operations Research, Systems Engineering and Industrial Engineering Commons^™

An Investigation On The Effectiveness Of A Problem Structuring Method In A Group Decision-Making Process, Ying Thaviphoke

Engineering Management & Systems Engineering Theses & Dissertations

There is no shortage of methods to address messy problems. A messy problem is a system of problems with multiple stakeholders who may hold different views of what is feasible or desirable. Decision-makers in a messy problem are prone to committing an error – especially the Type III error. One of the ways to mitigate the chance of committing the error in a messy problem is to reach a group consensus. Problem Structuring Methods (PSM) are the collections of participatory modeling methods that aim to tackle a messy problem. Despite the positive reports, literature indicates some challenges and criticisms of …

Comparison Of Classification Algorithms And Undersampling Methods On Employee Churn Prediction: A Case Study Of A Tech Company, Heather Cooper

Master's Theses

Churn prediction is a common data mining problem that many companies face across industries. More commonly, customer churn has been studied extensively within the telecommunications industry where there is low customer retention due to high market competition. Similar to customer churn, employee churn is very costly to a company and by not deploying proper risk mitigation strategies, profits cannot be maximized, and valuable employees may leave the company. The cost to replace an employee is exponentially higher than finding a replacement, so it is in any company’s best interest to prioritize employee retention.

This research combines machine learning techniques with …

The Effects Of Aircraft Use And Available Repar Spares On Aircraft Sortie Generaiton: A Long-Duration Logistical Wargaming Simulationtool, Nathaniel M. Choo

Theses and Dissertations

A long-duration logistical wargame simulation tool that can provide quick insights into the daily aircraft availability and the daily number of missions accomplished for a variety of operational scenarios is developed. This simulation tool is designed to be a stepwise wargaming support tool for adjudication within long-duration logistical wargames and provides the user many capabilities including, but not limited to, the ability to have multiple bases and types of aircraft. Additionally, the user has the ability to control types of part failures, control parts availability, control maintenance capabilities, and control number of mission scheduled. Finally, the user can account for …

Designing An Autonomous Goods-To-Person Order Picking System: From Storage To Pick., Mina Shekari Ashgzari

Electronic Theses and Dissertations

In recent years, there has been an increased growth in e-commerce, which is a special case of a business-to-customer model. Among all the operations for fulfilling online orders, order picking has been the concern of many researchers and practitioners in the field of warehousing and material handling. This is due to very different technical assumptions and service expectations for online retailers compared to the case of business-to-business models. The most fundamental change in order processing, imposed by business-to-customer models, is shipping individual items or “eaches,” instead of cases and pallets, which is typical of business-to-business models. As a result, the …

Development Of A Deformation-Based Structural Health System With Contactless Sensors And Machine Learning For Health Characterization And Failure Prediction, Juan Camilo Avendano Arbelaez

Theses and Dissertations

This dissertation presents the design and development of a structural health monitoring (SHM) system specifically tailored for transportation infrastructure components, such as bridges. The proposed system collects data by using contactless sensors and performs health characterization and failure prediction. It is capable of simulating multiple load conditions on structures, identifying possible failure points, and detecting and predicting failure scenarios. Both hardware and software implementations of a model of a bridge were performed as a pilot project in order to validate the proposed system. Computer simulation in ANSYS and the application of gradient boosting neural networks were performed to produce a …

ℓ-Ctp: Utilizing Multiple Agents To Find Efficient Routes In Disrupted Networks, Andrew Alseth

Graduate Theses and Dissertations

Recent hurricane seasons have demonstrated the need for more effective methods of coping with flooding of roadways. A key complaint of logistics managers is the lack of knowledge when developing routes for vehicles attempting to navigate through areas which may be flooded. In particular, it can be difficult to re-route large vehicles upon encountering a flooded roadway. We utilize the Canadian Traveller’s Problem (CTP) to construct an online framework for utilizing multiple vehicles to discover low-cost paths through networks with failed edges unknown to one or more agents a priori. This thesis demonstrates the following results: first, we develop the …

A Parametric Evaluation Of Iot Applications To Freight Transportation Using Model-Based Systems Engineering, Paul George Crawford

Theses and Dissertations

Industrial Internet of Things or IIoT consists of computing and communication at the operational edge of a value chain. Applications span manufacturing, energy, and transportation, among others. In the transportation context, IIoT translates to connected vehicle architecture and ITS applications. Current trends in communication allow more applications and devices to contribute to functions traditionally allocated to transportation ITS infrastructure. This poses challenges to design engineers to prototype emerging technologies in the existing transportation context and reduce integration, validation, and time to market. Model-based systems engineering is crucial step for IIoT deployment since it allows for a feature-rich digital representation of …

Optimal Collaborative Path Planning For Unmanned Surface Vehicles Carried By A Parent Boat Along A Planned Route, Ari Carisza Graha Prasetia, I-Lin Wang, Aldy Gunawan

Research Collection School Of Computing and Information Systems

In this paper, an effective mechanism using a fleet of unmanned surface vehicles (USVs) carried by a parent boat (PB) is proposed to complete search or scientific tasks over multiple target water areas within a shorter time . Specifically, multiple USVs can be launched from the PB to conduct such operations simultaneously, and each USV can return to the PB for battery recharging or swapping and data collection in order to continue missions in a more extended range. The PB itself follows a planned route with a flexible schedule taking into consideration locational constraints or collision avoidance in a real-world …

Parametric Study Of Residual Stresses In Wire And Arc Additive Manufactured Parts, Hisham Khaled Jamil Abusalma

Mechanical & Aerospace Engineering Theses & Dissertations

Wire and Arc Additive Manufacturing (WAAM) is a cost-effective additive manufacturing process due to its capability to fabricate large metal parts with high deposition rate and low equipment cost. Although this method is gaining popularity in manufacturing industry, more research is needed to understand process parameters’ effects on residual stress (RS) distribution and part distortion. As such, a 3D thermo-elastic-plastic transient model was established in ABAQUS and employed to investigate the effect of process parameters such as the torch speed, the deposition power and the interlayer dwell time on RS distribution and distortion in WAAM part. The numerical model utilized …

Systems Thinking In Engineering Design: Differences In Expert Vs. Novice And Relationship To Personality Traits, Yuzhen Luo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Systems thinking is the ability to see the big picture and the related elements when designing, and how these relationships form the big picture. In engineering design, systems thinking is valuable to both industry, as well as engineering education. As such, it creates opportunities for researchers to better understand systems thinking of both professional engineers in industry, who are assumed to be the experts, and engineering students in higher education, who are assumed to be the novices. The purpose of this study was to compare and identify the differences between expert and novice systems thinking in engineering design. Additionally, the …

Improvement Of Light Intensity And Efficiency Of N-Zno/Nio/P-Gan Heterojunction-Based White Light Emitting Diodes Using Micro-/Nanolens Array, Apurba Adhikary, Md Shamim Ahsan, Md Mahbub Hossain, Md Bipul Hossain, S. H. Shah Newaz, Farid Ahmed, Ik-Bu Sohn

Manufacturing & Industrial Engineering Faculty Publications

Our study proposes a technique to enhance light extraction efficiency of light emitting diodes (LEDs) by incorporating various micro-/nanolens arrays (MNLAs) on the substrate layer, which in turn increases the external quantum efficiency (EQE) of the LEDs. To simulate the LEDs, we utilized the finite difference time domain method. To achieve a white LED, we inserted a thin layer of NiO at the interface between the n-type ZnO and the p-type GaN. The basic n-ZnO/NiO/p-GaN heterojunction-based LED exhibited an EQE of 10.99% where the effective refractive index of the LED structure was 1.48. The EQE was further increased by engraving …

Demystifying Artificial Intelligence Based Digital Twins In Manufacturing- A Bibliometric Analysis Of Trends And Techniques, Satish Kumar, Shruti Patil, Arunkumar Bongale, Ketan Kotecha, Anup Kumar M. Bongale, Pooja Kamat

Library Philosophy and Practice (e-journal)

Nowadays, data is considered as a new life force for operations of physical systems in various domains such as manufacturing, healthcare, transportations, etc. However, the hugely generated data, which mirrors the working essence of the product life cycle, is still underutilised. Digital Twin (DT), a collective representation of active and passive captured data, is a virtual counterpart of the physical resources that could help prevent effective preventive maintenance in any applied domain. Currently, lots of research is going on about the applicability of digital twin in smart IOT based manufacturing industry 4.0 environment. Still, it lacks a formal study, which …

Influence Of Fiberboard Container Design On Compression Bulge Displacement, Koushik Saha, Shane Messner, John Dizon, Nirav Chhajed, Jay Singh

Journal of Applied Packaging Research

Bulge effect is the out-of-plane displacement of a panel of a corrugated fiberboard box from its original position. This bulge effect often is the result of excessive weight being placed on a box that rests at the bottom of a palletized load. Panels that are out-of-plane reduce the stacking strength of the box and can result in damage to products inside the containers. This study was designed to find the influence of fiberboard container design on its bulging performance when under compression. The objective of the study was to determine if change in height of a regular slotted container will …

Under Impact Of Non-Motor Vehicle Violation An Analysis On Vehicle Operation Efficiency, Sun Di, Zhou Jin, Sijia Liu, Xiaoming Zhang, Xueying Gao

Journal of System Simulation

Abstract: In order to study the impact of non-motor vehicle violations on motor vehicle traffic efficiency at signalized intersections, the non-motor vehicle traffic behaviors are analyzed. An actual intersection is selected as study object, the main violation behaviors of on selected intersection are analyzed by using the linear regression model. For traffic light violation behavior of non-motor vehicles, the violation rate is modeled by using logistic model, and the results are analyzed. At the signal controlled intersection, non-motor vehicle violations affect the normal motor vehicles, and time is delayed. The delay time of motor vehicle under non-motor vehicle …

Time-Varying Parameter System Modeling Method Based On Zonotope-Ellipsoid Double Filtering, Ziyun Wang, Peiyu Wang, Yacong Zhan

Journal of System Simulation

Abstract: The traditional system modeling method using zonotopes as the feasible parameter sets islikely to increase the computational complexity of the algorithm due to the increasing dimensions of the zonotope shape matrix. This paper proposes a time-varying parameter modeling systems method based on zonotope-ellipsoid double filtering technique. Considering the time-varying parameters, a zonotope with the minimum volume is obtained during the iterations of the intersection with the constraint strip. After transforming the shape matrix of the zonotope, the dimensionality reduction is performed, instead of directly finding the row sum of the extended shape matrix, to reduce the algorithm conservativeness originated …

Research On Configurable Simulation Integration Technology For Equipment Software, Yuanyuan Wang, Yuxin Duan, Guangzhao Song

Journal of System Simulation

Abstract: The problems of the traditional distributed digital simulation system are analyzed. The method of constructing the digital simulation system based on the equipment software is studied. The configurable simulation integration middleware is designed. The overall structure of the configurable middleware is designed and the design ideas of each module are briefly summarized. An example of a digital simulation system with networked transformation of equipment shows that the middleware can be effectively and flexibly configured and can provide support for constructing digital simulation system with software, which can be promoted and used in other simulation systems.

Research On Multi-Objective Optimization Method Based On Model, Jianjun Liu, Guangya Si, Yanzheng Wang, Dachuan He

Journal of System Simulation

Abstract: There is a model-based algorithm for the optimization of multiple objective functions by means of black-box evaluation is proposed. The algorithm iteratively generates candidate solutions from a mixture distribution over the solution space and updates the mixture distribution based on the sampled solutions’ domination count, such that the future search is biased towards the set of Pareto optimal solutions. The proposed algorithm seeks to find a mixture distribution on the solution space so that each component of the mixture distribution is a degenerate distribution centered at a Pareto optimal solution and each estimated Pareto optimal solution is uniformly spread …

Research And Application Of A Lightweight Real-Time Human Posture Detection Model, Hongkun Zhu, Jiawei Yin, Wenyu Feng, Hua Liang, Minrui Fei, Kun Zhang

Journal of System Simulation

Abstract: The traditional OpenPose model has good accuracy but slow speed in human posture detection. In order to accelerate the detection speed and reduce the model on condition of the detection precision, based on the traditional OpenPose model, the residual network with second-order term fusion is used to extract the low-level features, the weights of the trained model are pruned by the L1 norm weight, and an improved OpenPose model is proposed. Experiments show that when the detection accuracy is approximately equal to original model, the model size reduces to about 8%, the parameters reduces by nearly 83%, and the …

Construction And Test Method Of A Semi-Physical Simulation System For Laser Driving Guidance Weapon, Zhang Xiang, Mengyan Liu, Zhang Peng, Kewei Zhu, Xiaodong Yan

Journal of System Simulation

Abstract: To achieve the previous semi-physical simulation of the laser beam-guided weapon, the two-dimensional translation system must be used. But the technical index of the two-dimensional translation system is not high enough to meet the requirements of the relative motion simulation speed and acceleration of the projectile. To solve the problem, a new method and test method for the semi-physical simulation system of laser driving guidance weapon is proposed. The “two-axis turret + load bracket” simulation system construction method is adopted to replace the linear motion of the two-dimensional translation system by the rotational angular motion of the …

Two Gd Atoms Adsorbed On Zigzag Graphene Nanoribbon:A First-Principles Study, Weifeng Xie, Zuo Xu

Journal of System Simulation

Abstract: A giant Rashba-type spin splitting is highly critical for the application of spintronics, but one-dimensional magnetic systems are rarely involved. In order to explore the characteristics and strength of Rashba effect in one-dimensional magnetic systems, two Gd atoms adsorbed on Zigzag graphene nanoribbon system is proposed. The characteristics and strength of the Rashba effect in different magnetization directions and the magnetic anisotropy of the system are analyzed through the first-principles calculations. The results show that the antiferromagnetic ground state system has strong Rashba strength and out-of-plane magnetic anisotropy. In addition, the Rashba effect in magnetic system needs to …