Operations Research, Systems Engineering and Industrial Engineering Commons^™

3d Printing For Solving Part Obscolescence, Ayman G. Alqarni

Theses and Dissertations

The purpose of this research was to highlight the issue of parts obsolescence and to highlight the possibility of using alternative methods to overcome parts shortage. Specifically, this thesis sought to answer the research question: is the three-dimensional printing technology (3D) an applicable approach to overcome part obsolescence. The research question was answered through data research and survey analysis. Notwithstanding, the diminished manufacturing sources and material shortages (DMSMS) management and other existing approaches, such as forecasting, contracting, and reverse engineering (RE), were discussed briefly in the literature review and profoundly in chapter IV to differentiate among applicable existing solutions toward …

Operationalized Intent For Improving Coordination In Human-Agent Teams, Michael F. Schneider

Theses and Dissertations

With the increasing capabilities of artificial intelligent agents (AIAs) integrated into multi-agent systems, future concepts include human-agent teams (HATs) in which the members perform fluidly as a coordinated team. Research on coordination mechanisms in HATs is largely focused on AIAs providing information to humans to coordinate better (i.e. coordination from the AIA to the human). We focus on the compliment where AIAs can understand the operator to better synchronize with the operator (i.e. from the human to the AIA). This research focuses specifically on AIA estimation of operator intent. We established the Operationalized Intent framework which captures intent in a …

Survey Of Airflow Around A Heated Manikin As A Simulated Aeromedical Evacuation Patient On A Litter With Computational Fluid Dynamics Models, George P. Lemmer

Theses and Dissertations

Aeromedical Evacuations remain the predominant method used to transport patients from forward deployed areas of operations to secure locations with more robust medical infrastructure. Transportation of chemical warfare casualties and infectious patients require additional attention to prevent cross contamination. Specific airflow characteristics paired with environmental control system settings are a gap in scholarly literature. Based on the available literature computational fluid dynamics models were created to simulate the airflow around a patient represented by human geometry using commercially available software. In order to compare simulated and experimental results a heated manikin was placed in the MURPHEE aerosol exposure chamber and …

Analysis Of The Factors That Correlate With Transition Outcomes Of Commercial Technology Prototype Projects, Matthew D. Schoemaker

Theses and Dissertations

A key metric of success for Department of Defense (DoD) Research and Development organizations is the ability to transition technologies and prototypes. Office of the Undersecretary of Defense for Research and Engineering's prototyping guide shows successful transition pathways come in the forms of transition to operational use, rapid fielding, existing program adoption, or a new acquisition program (2018). There are many factors that occur throughout a prototype projects lifecycle that impact the likelihood of transition. These factors include both qualitative and quantitative factors. Limited research has been performed, past the best practice considerations, of what factors impact transition of prototyping …

Trainer Appropriation And Transfer Of A New Prevention Approach In Material Handling Based On Action Principles, Denys Denis, Maud Gonella, Marie Comeau, Martin Lauzier

Rapports de recherche scientifique

Mise en contexte et objectif

Prenant acte du constat d’échec des formations à la manutention axées sur l’enseignement exclusif de la technique sécuritaire « dos droit – genoux fléchis », une nouvelle approche d’intervention dite « stratégie intégrée de prévention en manutention » (SIPM) a été proposée en 2011. Son originalité repose, entre autres, sur l’utilisation de neuf principes d’action permettant de comprendre et de commenter la richesse des techniques de manutention utilisées naturellement par les manutentionnaires dans leur milieu de travail. L’étude a pour objectif central d’évaluer l’appropriation et le transfert de la SIPM par un groupe d’intervenants formés …

Large Signal Modeling For Llc Resonant Converter, Zheng Kai, Jianbing Li, Zhou Dongfang, Li Kai, Songzhen Zhang

Journal of System Simulation

Abstract: The large-signal model modeling issue of LLC resonant converter was dealt with by using averaged large-signal modeling method, on the basis of a full-bridge LLC voltage-multiplying resonant converter. The SSOC (self-sustained oscillation controller) was analyzed, and the operation mode of LLC resonant converter under the SSOC mode was investigated. The nonlinear state space model of LLC resonant converter was established by analyzing linear approximation of nonlinear terms and harmonic balance, and the averaged large-signal model of LLC resonant converter was proposed. Two curves of large signal model and nonlinear state space model were proved to be identical …

Construction Of Virtual Atmospheric Environment Based On Mm5 And Sedris, Lianlei Lin, Ding Wei

Journal of System Simulation

Abstract: The new virtual test for virtual atmosphere environment puts forward higher requirements, such as providing complex atmospheric environment which includes a variety of atmospheric parameters and improving usability and reusability of atmospheric environment data. A method to construct virtual atmospheric environment based on MM5 and SEDRIS was proposed which met the above demands. The original data of complex atmospheric environment in any region and scale was generated by using MM5 model. According to the characteristics as well as the dynamic relationship between time and space of grid of atmospheric data, SEDRIS was selected to regulate appropriate DRM class, SRF …

Bus Frequency Optimization: When Waiting Time Matters In User Satisfaction, Songsong Mo, Zhifeng Bao, Baihua Zheng, Zhiyong Peng

Research Collection School Of Computing and Information Systems

Reorganizing bus frequency to cater for the actual travel demand can save the cost of the public transport system significantly. Many, if not all, existing studies formulate this as a bus frequency optimization problem which tries to minimize passengers’ average waiting time. However, many investigations have confirmed that the user satisfaction drops faster as the waiting time increases. Consequently, this paper studies the bus frequency optimization problem considering the user satisfaction. Specifically, for the first time to our best knowledge, we study how to schedule the buses such that the total number of passengers who could receive their bus services …

Solar Power Forecasting Using Wavelet Transform And Machine Learning Approaches, Abdullah Nor Azliana

Student Works (2020-2029)

Generation of photovoltaic (PV) power is intermittent in nature and integration of PV system into the grid system causes an imbalanced power production and power demand. One of the efforts to reduce this problem is to forecast the generation of solar power in the PV system. Solar power forecasting requires the collection of solar power and meteorological data. Hence, this work collected solar power data and various meteorological data (global radiation, tilted radiation, temperature surrounding, humidity surrounding, PV module/ PV panel temperature and wind speed) from Universiti Teknikal Malaysia Melaka (UTeM). A pre-processing process is carried out to ensure that …

Aligning Performance Management Systems For Lasting Outcomes In Humanitarian Operations, Kalyn M. Howard

Theses and Dissertations

Logistics is dynamic, expansive, and critical to organizational success. While it is generally believed that effective logistics management is associated with positive performance outcomes, the links between organizational practice and performance are understudied. This dissertation leverages resource-based theory and organizational learning theory to examine organizational practice and performance in non-traditional logistics settings, with particular focus on military organizations and humanitarian operational settings. First, a meta-analytical study establishes generalizable associations between various operations management practices and performance outcomes. Then, this is applied to dynamic humanitarian logistics settings, exploring how practitioners perceive practice and performance, and how this is reported and documented …

A Hybrid Framework Using A Qubo Solver For Permutation-Based Combinatorial Optimization, Siong Thye Goh, Sabrish Gopalakrishnan, Jianyuan Bo, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In this paper, we propose a hybrid framework to solve large-scale permutation-based combinatorial problems effectively using a high-performance quadratic unconstrained binary optimization (QUBO) solver. To do so, transformations are required to change a constrained optimization model to an unconstrained model that involves parameter tuning. We propose techniques to overcome the challenges in using a QUBO solver that typically comes with limited numbers of bits. First, to smooth the energy landscape, we reduce the magnitudes of the input without compromising optimality. We propose a machine learning approach to tune the parameters for good performance effectively. To handle possible infeasibility, we introduce …

Research About Method Of Face Detection And Tracking Based On Active Vision, Enzeng Dong, Shengxu Yan, Jigang Tong

Journal of System Simulation

Abstract: Based on the method of combining the Camshift algorithm mixing Kalman filter with Adaboost algorithm, a face-detection and tracking algorithm on the active vision was proposed. The algorithm proposed realized the face automatic detection and tracking by using Adaboost algorithm and Camshift mixed algorithm; according to the positional relation of target centroid and the view centre, and the difference of area between the region of the face target and the view, the Pan-Tilt-Zoom (PTZ) control algorithm was designed. Through the rules designed for pan, tilt and zoom control, the algorithm achieved the goal of …

Three-Dimensional Fuzzy Control Of Catheter Robotic In Endovascular Master-Slave Interventional Surgery, Ximei Zhao, Jiankang You, Liu Hao, Hongyi Li

Journal of System Simulation

Abstract: In minimally invasive endovascular interventional surgery, catheter was vulnerable to be interfered by uncertain factors such as heartbeat and breathing of patients during catheter robot of slave side conveyed catheter. In order to retrain impact on catheter transport of these factors and realize that slave side of catheter robot system tracked control command of master side accurately and quickly, kinematic model of catheter distal bending section was established, and catheter robot system based on three-dimensional fuzzy controller was designed. Three-dimensional fuzzy controller that introduced the function of rate of error change on the basis of two-dimensional fuzzy controller …

Velocity Deception Jamming Analysis Of Coherent Video Simulation Of Anti-Ship Pd Seeker, Cuiqiong Mo, Jiahai Li, Huanyao Dai, Qiuju Chen, Zhao Jing

Journal of System Simulation

Abstract: According to existed experimental evaluation of radar electronic jamming simulation for terminal guidance, the ballistic calculation model was simplified relatively. Particle model was usually adopted which made simulation results have serious distortion. The pulse Doppler radar seeker was discussed in six degree of freedom trajectory simulation of the closed loop (PDRS) for coherent video simulation, and simulation results show that the VGPO has no direct effect on the angle tracking loop, just through guidance filter affects the convergence angle velocity estimation, which leads to little change of guidance precision. The conclusion and anechoic chamber measurements results show that the …

Algorithm For Solving Symmetric Cone Complementarity Problems, Leifu Gao, Dongmei Yu

Journal of System Simulation

Abstract: A monotonic trust region algorithm for symmetric cone complementarity problems was proposed based on a smoothing function. The problem was transformed into unconstrained optimization problem and the trust region subproblem was constructed. The problem was solved by using trust region algorithm combined with nonmonotonic strategies, and the global convergence of the algorithm was proved. Numerical experimental results demonstrate that the algorithm is effective for symmetric cone complementarity problems.

Pid Closed Loop Control Performance Analysis Of Piezostack-Driven Jet Dispensing Valve, Yunbo Fu, Xinbo Li, Guojun Liu, Jianfang Liu, Yaowu Shi

Journal of System Simulation

Abstract: A new type of piezostack-driven jetting dispenser was proposed which used hydraulic magnification, and analyzed its injection process and injection condition. The open loop model of dispensing system was built by AMESim software. The simulation proved the feasibility. The closed loop control system with PID (Proportion Integration Differentiation) algorithm was set up to improve performance of open loop dispensing system, and the open and closed loop control performance was compared under the simulation environment. Analysis shows that PID closed loop system can improve performance of piezostack-driven jetting dispensing system. When nozzle diameter is 0.1mm and syringe pressure …

A Genetic Algorithm To Minimise Number Of Vehicles In An Electric Vehicle Routing Problem, Kiian Leong Bertran Queck, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Electric Vehicles (EVs) and charging infrastructure are starting to become commonplace in major cities around the world. For logistics providers to adopt an EV fleet, there are many factors up for consideration, such as route planning for EVs with limited travel range as well as long-term planning of fleet size. In this paper, we present a genetic algorithm to perform route planning that minimises the number of vehicles required. Specifically, we discuss the challenges on the violations of constraints in the EV routing problem (EVRP) arising from applying genetic algorithm operators. To overcome the challenges, techniques specific to addressing the …

Simulation Of Physical Field Of 300ka Prebaked Aluminum Reduction Cell, Shuiping Zeng, Shasha Wang, Rongjuan Wang

Journal of System Simulation

Abstract: The SY300 Prebake cell of some factory as a basic simplified model, the solidworks software was used to build a three-dimensional physical model of aluminum reduction cell. In the use of some assumptions, reasonable ideal field segmentation and under the premise of sharing model information and results, the physical model of electric field, magnetic field, flow field and its calculation module of coupling field were established respectively by using the the finite element software Comsol and Matlab Multiphysics software. On Comsol platform, electric, magnetic field of aluminum electrolytic cell were solved when replacing the anode, and current density …

Low Complexity Method Based On Fc-Ce-Slm For Papr Reduction In Ofdm System, Ce Ji, Lijuan Wang

Journal of System Simulation

Abstract: Selected mapping (SLM) algorithm uses Cross Entropy (CE) algorithm to get the most optimal sign sequence so that SLM can make the effect of PAPR Reduction achieve optimum. However, it needs too many times iterative computations, so it will increase the complexity of the algorithm. In order to solve this problem, a fast convergence factor in the CE-SLM algorithm was introduced to make the sampling probability converge to 0 or 1 quickly in the system, which reduced the iterative times of getting the optimal sign sequence. Computer simulation results show that the approved algorithm reduces the iterative times of …

Research On Parallel Simulation Of Hypersonic Vehicles, Xuegong Sun, Chunye Gong

Journal of System Simulation

Abstract: The system simulation of hypersonic vehicles was a multi-physics coupling process. It needed many iterations with large scale data to finish the simulation. To fix up the computational challenges, the distributed simulation was developed. But distributed simulation had no obvious effect on the computational efficiency. In order to enhance the computational efficiency, the grid parallel method and model parallel algorithm were studied based on the high performance cluster system. The parallel simulation method for fluid dynamics, data exchange method for partition boundary and load balance technology for parallel computing were developed and applied to the system simulation of hypersonic …