Operations Research, Systems Engineering and Industrial Engineering Commons^™

Ultrafast Laser Ablation Of Inconel 718 For Surface Improvement, Sampson Canacoo, Enrique Contreras Lopez, Oscar Coronel, Farid Ahmed, Jianzhi Li, Anil K. Srivastava

Manufacturing & Industrial Engineering Faculty Publications

Inconel 718 is considered difficult to machine because of its ability to maintain its properties at high temperatures. The low thermal conductivity of the alloy causes accelerated tool deterioration when machining. Selective laser melting (SLM) additive manufacturing introduces a possibility of eliminating these difficulties, and producing complex shapes with this difficult-to-machine material. However, high surface roughness and porosity usually occur at the surface of components produced through additive manufacturing. In this study, the surfaces of Inconel 718 samples produced through selective laser melting were treated using laser ablation. The process parameters for the laser ablation process were analyzed in …

A Methodological Framework For Parametric Combat Analysis, Dustin L. Hayhurst Sr.

Theses and Dissertations

This work presents a taxonomic structure for understanding the tension between certain factors of stability for game-theoretic outcomes such as Nash optimality, Pareto optimality, and balance optimality and then applies such game-theoretic concepts to the advancement of strategic thought on spacepower. This work successfully adapts and applies combat modeling theory to the evaluation of cislunar space conflict. This work provides evidence that the reliability characteristics of small spacecraft share similarities to the reliability characteristics of large spacecraft. Using these novel foundational concepts, this dissertation develops and presents a parametric methodological framework capable of analyzing the efficacy of heterogeneous force compositions …

Evaluating Performance Competencies In The Royal Saudi Air Force Engineering Directorate And Squadrons, Faisal A. Al Dawood

Theses and Dissertations

The effectiveness of tasks performed by the directorate of aeronautical engineering and squadrons in RSAF directly impacts flight safety, which in turn influences the organization either positively or negatively. Therefore, improving engineers' competencies will improve the overall performance of the organization. The study refined and reconstructed a model, namely a T-shape competency model, to assess the engineers' competencies which revealed some management and competency-related deficiencies and concluded with managerial recommendations.

Root-Cause Analysis Of Rsaf Maintenance-Related Flight Safety Mishaps, Heaf H. Alqahtani

Theses and Dissertations

Poor maintenance is a major factor in many aviation mishaps. This is due to the fact that some maintenance activities are carried out improperly or overlooked as a result of human error. It is important to acknowledge that maintenance mistakes are a visible sign of deeper organizational issues. Therefore, adequate solutions to maintenance issues must consider organizational influences. Despite efforts to reduce the accident rate within the Royal Saudi Air Force (RSAF), the RSAF suffers from an increasing trend in mishaps attributed to maintenance. Therefore, safety data was analyzed to examine trends. Additionally, the Human Factors Analysis and Classification System …

A Carbon-Aware Planning Framework For Production Scheduling In Mining, Nurual Asyikeen Azhar, Aldy Gunawan, Shih-Fen Cheng, Erwin Leonardi

Research Collection School Of Computing and Information Systems

Managing the flow of excavated materials from a mine pit and the subsequent processing steps is the logistical challenge in mining. Mine planning needs to consider various geometric and resource constraints while maximizing the net present value (NPV) of profits over a long horizon. This mine planning problem has been modelled and solved as a precedence constrained production scheduling problem (PCPSP) using heuristics, due to its NP-hardness. However, the recent push for sustainable and carbon-aware mining practices calls for new planning approaches. In this paper, we propose an efficient temporally decomposed greedy Lagrangian relaxation (TDGLR) approach to maximize profits while …

Two-Phase Matheuristic For The Vehicle Routing Problem With Reverse Cross-Docking, Aldy Gunawan, Audrey Tedja Widjaja, Pieter Vansteenwegen, Vincent F. Yu

Research Collection School Of Computing and Information Systems

Cross-dockingis a useful concept used by many companies to control the product flow. It enables the transshipment process of products from suppliers to customers. This research thus extends the benefit of cross-docking with reverse logistics, since return process management has become an important field in various businesses. The vehicle routing problem in a distribution network is considered to be an integrated model, namely the vehicle routing problem with reverse cross-docking (VRP-RCD). This study develops a mathematical model to minimize the costs of moving products in a four-level supply chain network that involves suppliers, cross-dock, customers, and outlets. A matheuristic based …

Choice-Based Crowdshipping: A Dynamic Task Display Problem, Alp Arslan, Firat Kilci, Shih-Fen Cheng, Archan Misra

Research Collection School Of Computing and Information Systems

This paper studies the integration of the crowd workforce into a generic last-mile delivery setting in which a set of known delivery requests should be fulfilled at a minimum cost. In this setting, the crowd drivers are able to choose to perform a parcel delivery among the available and displayed requests. We specifically investigate the question: what tasks should be displayed to an individual driver, so as to minimize the overall delivery expenses? In contrast to past approaches, where drivers are either (a) given the choice of a single task chosen so as to optimize the platform’s profit, or (b) …

Computation Of Risk Measures In Finance And Parallel Real-Time Scheduling, Yajuan Li

Dissertations

Many application areas employ various risk measures, such as a quantile, to assess risks. For example, in finance, risk managers employ a quantile to help determine appropriate levels of capital needed to be able to absorb (with high probability) large unexpected losses in credit portfolios comprising loans, bonds, and other financial instruments subject to default. This dissertation discusses the computation of risk measures in finance and parallel real-time scheduling.

Firstly, two estimation approaches are compared for one risk measure, a quantile, via randomized quasi-Monte Carlo (RQMC) in an asymptotic setting where the number of randomizations for RQMC grows large, but …

Optimizing Incentives For Systems With Heterogeneous Agents, Chen Chen

Dissertations

This dissertation explores new models and applications based on the game theory of incentives. This exploration starts with controlling an invasive insect problem to address one of the most significant challenges facing our forests, the invasion of the Emerald ash borer (EAB), a non-native, wood-boring insect that threatens to kill most ash trees in North America, through designing two new cost-sharing programs between the landowners and local governments. Ash trees are one of North America’s most widely distributed tree genera and a vital part of the green infrastructure of cities, where they provide residents with numerous social, economic, and ecological …

Back And Shoulder Exoskeletons For Occupational Use: A Review, Erkan Ozan

Theses

Work-related musculoskeletal disorders (MSDs) account for a large portion of all work-related injuries according to OSHA. Back and shoulder-related disorders make the most of work-related MSDs according to the Bureau of Labor Statistics (BLS). Exoskeletons emerged in recent years with the potential to reduce the risks of work-related musculoskeletal disorders and injuries. Their use in occupational settings is increasing, and exoskeleton designs are rapidly evolving. This paper reviewed recent scientific articles (2015 and after) that evaluated back and shoulder-support passive industrial exoskeletons. The findings of these articles are summarized and analyzed to assess the benefits of passive upper-body exoskeletons by …

Evaluating Safety And Productivity Relationship In Human-Robot Collaboration, Aayush Jain, Shakra Mehak, Philip Long, John D. Kelleher, Michael Guilfoyle, Maria Chiara Leva

Conference papers

Collaborative robots can improve ergonomics on factory floors while allowing a higher level of flexibility in production. The evolution of robotics and cyber-physical systems in size and functionality has enabled new applications which were never foreseen in traditional industrial robots. However, the current human-robot collaboration (HRC) technologies are limited in reliability and safety, which are vital in risk-critical scenarios. Certainly, confusion about European safety regulations has led to situations where collaborative robots operate behind security barriers, thus negating their advantages while reducing overall application productivity. Despite recent advances, developing a safe collaborative robotic system for performing complex industrial or daily …

Artificial Neural Networks And Gradient Boosted Machines Used For Regression To Evaluate Gasification Processes: A Review, Owen Sedej, Eric Mbonimpa, Trevor Sleight, Jeremy M. Slagley

Faculty Publications

Waste-to-Energy technologies have the potential to dramatically improve both the natural and human environment. One type of waste-to-energy technology that has been successful is gasification. There are numerous types of gasification processes and in order to drive understanding and the optimization of these systems, traditional approaches like computational fluid dynamics software have been utilized to model these systems. The modern advent of machine learning models has allowed for accurate and computationally efficient predictions for gasification systems that are informed by numerous experimental and numerical solutions. Two types of machine learning models that have been widely used to solve for quantitative …

Mission Operations, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Overview

• In review – CONOPS

• Mission Planning

• Anomaly Resolution

• Miscellaneous, but important considerations

• Looking forward

Image Dehazing Network Based On Densely Connected Residual Block And Channel Pixel Attention, Weidong Jin, Shuli Zhang, Peng Tang, Man Zhang

Journal of System Simulation

Abstract: Abstruct: A lot of research achievements have been made in image dehazing based on neural network,but there aiming at the fog residue, even the color distortion and texture loss, in complex outdoor image dehazing, an image dehazing network based on densely connected residual block and channel pixel attention is proposed. Densely connected residual blocks are used to extract and fuse the features of foggy images,and the repair module with channel pixel attention mechanism is used to repair the color and texture of the feature maps. The experimental results show that, compared with the existing methods, the proposed method and …

Research On Motion Recognition And Tracking For Space Survey And Launch Tasks, Bin Ren, Xiaoyu Wang

Journal of System Simulation

Abstract: Space survey and launch task has high precision and long cycle, and needs to be exposed to direct sunlight for a long time, so that the non-contact action calibration and comparison in a virtual working environment is an efficient way to improve the mission completion success rate. Aiming at the real-time motion tracking of aerospace personnel, a keyframe optimization algorithm for the action recognition is proposed. According to the bone data in the depth image, the bone features are extracted, and the keyframes are extracted by the feature threshold. The characteristic data of the keyframe is input into bi-directional …

Sensorless Control Of Pmsm Based On An Anfis Optimized Flux Sliding Mode Observer, Huilin Zhang, Yujie Jin, Haima Yang

Journal of System Simulation

Abstract: Aiming at the low estimation accuracy of rotor speed and position and the system chattering in sensorless control of permanent magnet synchronous motor (PMSM), an adaptive neuro-fuzzy inference system (ANFIS) is proposed to optimize the flux sliding mode observer(FSMO). Compared with the traditional sliding mode observer, the FSMO improves the estimation accuracy of the rotor flux. The FSMO optimized by ANFIS realizes the on-line adjustment of the observer gain and reduces the system chattering. The improved PLL improves the estimation accuracy of the rotor speed and position. A simulation platform is established to verify the results which show …

Simulation Of Unmanned Tank Clusters Cooperative Combat Based On Military Rules, Chunyan Wang, Hao Ren, Minchi Kuang, Danfeng Wu, Xiangshu Cao, Heng Shi

Journal of System Simulation

Abstract: Modern warfare is developing towards the unmanned, informatized, and intelligent form. Being the important combat equipment in the future land warfare, unmanned tanks have greater advantages of mobility, safety, and economy. Single unmanned tank can not fulfill the complex tasks of large-scale battles as the cooperation of unmanned tank clusters can do. Focuses on the collaborative applications of unmanned tank clusters, the single unmanned tank system model is established, including dynamic control, decision-making, and weapon armor. A collaborative perception model of unmanned tank clusters is designed considering the unmanned tank's own state and the fusion situation. Based on the …

Modeling Of Traffic Flow Velocity Control Strategy For Human-Machine Mixed Driving At Signalized Intersections, Jianxu Zhang, Shuai Hu, Hongyi Jin

Journal of System Simulation

Abstract: In order to analyze the influence of speed control strategy of autonomous vehicle on the operation characteristics of traffic flow, a deterministic decision-making model for intersections with artificially driven vehicles considering the driver's influence on the acquisition of driving information is constructed. An automatic driving speed control strategy considering the influence of the speed of preceding vehicle is proposed, and the continuous Cellular Automata update rules for signalized intersections are constructed respectively. By introducing the different penetration rates of automatic driving, road saturation and control area length parameters, the influence of CAV speed control strategy on the traffic …

Research On Passenger Ship Evacuation Simulation Based On Social Force Model, Qimiao Xie, Shuaishuai Guo

Journal of System Simulation

Abstract: Aiming at the influence of group behavior and different evacuation methods on the passenger ship evacuation process. Three evacuation methods of passengers arriving at the assembly stations with and without group behavior are provided, and the passenger assembly time, congestion area, congestion timing and duration are analyzed. The simulation results show that the group behavior has a significant effect on the passenger assembly time and increases the variation range of the passenger assembly time, and the congestion area with and without group behavior remains the same. The influences of group behavior on the congestion timing and duration are complicated, …

Layout Planning Of Metro-Based Underground Logistics System Network Considering Fuzzy Uncertainties, Wanjie Hu, Jianjun Dong, Rui Ren, Zhilong Chen

Journal of System Simulation

Abstract: Aming at the network design and optimization of metro-based urban underground logistics under uncertainties, the facility components of two-tier metro-based underground logistics system (M-ULS) are proposed. Focus on the comprehensive costs and system utilization rate, a M-ULS network flow assignment model is established based on the expectation of environmental benefits of underground freight transport. a M-ULS network location-allocation-routing fuzzy random programming model is established, and a crisp linearization method is presented. A solution portfolio combining discrete binary chaos particle swarm optimization-genetic algorithm and exact algorithms is designed for combinatorial optimization. Effectiveness of the presented models and algorithms is verified …