Operations Research, Systems Engineering and Industrial Engineering Commons^™

All-Metallic Phase Change Thermal Management Systems For Transient Spacecraft Loads, Carl R. Hartsfield, Travis E. Shelton, Brian O. Palmer, Ryan P. O'Hara

Faculty Publications

In this work, we explore the thermal properties of gallium as an effective phase change material for thermal management applications. Thermal storage and dissipation of gallium manufactured heat sinks were compared to conventional phase change heat sinks. The comparison revealed a 50-fold (80 K versus 1.5 K) potential reduction in temperature during the phase change process due to the high density, thermal conductivity, and latent heat of fusion. The gallium creates shallow thermal gradients when transiently heated, producing a nearly isothermal process. Computational estimates using lumped sum parameters were able to provide simple modeling to predict the results. Gallium based …

Study On New Sampling Plans And Optimal Integration With Proactive Maintenance In Production Systems, Sinan Obaidat

Graduate Theses and Dissertations

Sampling plans are statistical process control (SPC) tools used mainly in production processes. They are employed to control processes by monitoring the quality of produced products and alerting for necessary adjustments or maintenance. Sampling is used when an undesirable change (shift) in a process is unobservable and needs time to discover. Basically, the shift occurs when an assignable cause affects the process. Wrong setups, defective raw materials, degraded components are examples of assignable causes. The assignable cause causes a variable (or attribute) quality characteristic to shift from the desired state to an undesired state.

The main concern of sampling is …

Gender Differences And Cockpit Design, Susan Archer, Heidi Brewer, Stacie Fain, Stephanie Smith

Student Works

The design project reported in this paper examined female pilots’ experiences with how well or poorly cockpit design allowed them to safely accomplish their flying missions. The general aviation aircraft cockpit is not designed for female pilots, often causing them to find ways to adapt to the cockpit in order to operate the aircraft safely. Two primary focal areas for adaptations address issues with accessibility of controls and “viewability” inside and outside the cockpit. The design team used a Situation Awareness-Oriented Interface Design (SAOD) approach in preparing cockpit design recommendations for general aviation aircraft that would accommodate female pilots.

Feature Bagging And Extreme Learning Machines: Machine Learning With Severe Memory Constraints, Kallin Khan, Edward Ratner, Robert Ludwig, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

With the Onset of Easy Access to Supercomputers with High Amounts of Memory Available, Machine Learning Algorithms Have Continued to Increase the Resources Necessary to Perform their Data Analysis. This Paper Aims to Show Development in the Other Direction, by Showing that through the Use of a Combination of Feature Bagging and Ensembles of Extreme Learning Machines (Elms) It is Possible to Leverage Machine Learning, Without Loss of Accuracy, on Devices Where Flash Memory is Very Scarce, and Random-Access Memory (Ram) is Even Scarcer, Such as on Embedded Systems. This Novel Strategy is Called Feature Bagged Extreme Learning Machines (Fb-Elms).

Towards A Cyber-Physical Manufacturing Cloud Through Operable Digital Twins And Virtual Production Lines, Md Rakib Shahriar

Graduate Theses and Dissertations

In last decade, the paradigm of Cyber-Physical Systems (CPS) has integrated industrial manufacturing systems with Cloud Computing technologies for Cloud Manufacturing. Up to 2015, there were many CPS-based manufacturing systems that collected real-time machining data to perform remote monitoring, prognostics and health management, and predictive maintenance. However, these CPS-integrated and network ready machines were not directly connected to the elements of Cloud Manufacturing and required human-in-the-loop. Addressing this gap, we introduced a new paradigm of Cyber-Physical Manufacturing Cloud (CPMC) that bridges a gap between physical machines and virtual space in 2017. CPMC virtualizes machine tools in cloud through web services …

How Does Robotic Surgery Influence Communication, Leadership, And Team Outcomes? A Multimethod Examination., Jordan E. Rogers

Doctoral Dissertations and Master's Theses

The practice of delivering surgical care has evolved to be less invasive to the patients undergoing surgery. Minimally-invasive surgery can be practiced through traditional laparoscopic methods as well as with robotic technology that displaces the surgeon from the operating table. Robotic surgery has been cited to be safer and more effective than traditional laparoscopic surgery; however, little research has endeavored to investigate the role of surgical modality upon aspects of teamwork. This dissertation contributes to the human factors and teamwork literature by evaluating how surgical modality may influence communication, shared leadership, and team outcomes. Multiple methods were employed to study …

Simulation-Based An Exploratory Analysis Of Drone Air Strike On Saudi Oilfields, Jiajun Zhang, Xiaochao Qian, Jinpeng Zhou, Xuanling Wang, Zhifeng Lu

Journal of System Simulation

Abstract: The incident of air strike in Sandi Arabia in September 2019 is taken as an example，A rapid analysis method for crisis events based on simulation is proposed. Combining the simulation with the exploratory analysis, the uncertainty of crisis events is comprehensively analyzed and dealt with. According to the public information of the incidents details from Sandi Arabia, Yemen, the combat situation of the air strike is replayed based on the wargaming. The rationality and authenticity of the details in the event statement is verified and can also provide reference to the development and combat research of the “Low, Small …

Multi-Tank Adaptive Scheduling Algorithm And Simulation For Ship Stability Realization, Xiong Yong, Xuanzhuo Liang, Zhang Jia

Journal of System Simulation

Abstract: Aiming at the influence of the oil tank on the floating state and stability of the ship, the multi-tank adaptive dispatching control algorithm to maintain the stability of the ship is studied. The automatic floating state adjustment simulation system of the ship is realized by the WinCC (Windows Control Center) configuration software. For the system architecture, the Boolean logic table is used to construct the connection relationships of the oil tanks, pumps and pipelines, and the amount of oil exchange between the cabins is calculated according to the floating equation, and the balance of the floating state in the …

Simulation-Based Effectiveness Evaluation For System-Of-System Under Multi-Equipment Collaboration, Ma Ning, Shenglin Lin

Journal of System Simulation

Abstract: Complex coordination exists among the various equipment in the system-of-system (SoS) operational process. The influence relationship among the various indexes is ignored in the traditional effectiveness evaluation methods. Aiming at this, a new effectiveness evaluation approach for the SoS is proposed. Numerous evaluation data is analyzed, based on the association rules mining, to obtain the influence among the effectiveness indexes. The networked evaluation index system is constructed, and the effectiveness integration evaluation is realized based on the analytic network process. The feasibility and validity of the proposed method are verified by evaluating the effectiveness of an air defense SoS.

Identification Method For Fractional-Order Systems Based On Haar Wavelet Operational Matrix, Yuanlu Li, Li Teng, Baoying Liu

Journal of System Simulation

Abstract: Studies have shown that the dynamical systems can be more accurately described by the fractional-order systems because its order can be any number. That’s why the fractional-order systems are being paid more and more attention. However, how to create a fractional-order system is still in the exploratory stage. Considering the nonlocal features of the fractional differentiation, a method for the fractional-order system identification is proposed by taking the Haar wavelet operational matrix. The proposed method can reduce the dimension of the operational matrix by abandoning the high frequency coefficients of the input and output signals so that the buffer …

Classification Of Chest X-Ray Disease Based On Convolutional Neural Network, Huang Xin, Fang Yu, Mengdan Gu

Journal of System Simulation

Abstract: The artificial intelligence technology can effectively assist the chest X-ray diagnosis. On the basis of the analysis of Chinese reports of chest X-rays, a labeling method of the thoracic disease classification for the chest abnormal parts is proposed and a dataset of the thoracic disease classification labels is complied. The thoracic disease classification is evaluated through four kinds of convolutional neural networks, AlexNet, VGGNet, ResNet and DenseNet and through three kinds of training methods, direct training, ImageNet pre-training and Chest X-14 pre-training. The result shows that the more complicated convolutional neural network with the more parameters, the better performance …

Study Of Parallelized Graph Clustering Algorithm Based On Spark, Dongjiang Liu, Jianhui Li

Journal of System Simulation

Abstract: The parallelized graph clustering algorithm is researched. A new parallelized graph clustering algorithm is proposed based on Spark. As the top operation of Spark occupies a lot of memory space, a new algorithm which is used to substitute the top operation is proposed to reduce the memory consumption. By improving bottom up hierarchical clustering algorithm, the speed of the proposed algorithm is improved. A new data filtering method based on the feature of graph data is proposed. By the method, the running time and memory space comsuption is reduced greatly. The reason of the high efficiency of this filtering …

A Multi-Strategy Differential Evolution Algorithm Combined With Neighborhood Search, Can Sun, Xinyu Zhou, Mingwen Wang

Journal of System Simulation

Abstract: The difficulties of designing a multi-strategy differential evolution (DE) algorithm are how to select the mutation strategies and allocate these strategies. A multi-strategy DE algorithm combined with the neighborhood search operator is proposed. The population is divided into three subpopulations according to the fitness values, and each subpopulation employs a different mutation strategy and parameter settings to complement the search ability, to balance the exploration and exploitation ability of the whole population. The subpopulation with the best fitness values employs the neighborhood search operator to exploit possible benefit information to guide the search. Extensive experiments are carried out on …

Holiday Highway Traffic Flow Prediction Method Based On Deep Learning, Xiaofeng Ji, Yicheng Ge

Journal of System Simulation

Abstract: Accurately predicting highway traffic holiday flow can provide important data for the emergency management of highway. The LSTM-SVR prediction model is established by using the theoretical framework of deep learning. The BP neural network is used to process the sample data, and the data features captured by LSTM are input into the SVR regression layer to realize the traffic flow prediction. Before and after the “Eleventh” Golden Week, the LSTM-SVR model was verified by using the traffic monitoring data of the intermodulation station in Lijiang City and the prediction results were compared with the others. It is found that …

Study On Evacuation Cellular Automaton Model Considering Avoidance Behavior, Yinghua Song, Zhang Yu, Feizhou Huo, Lü Wei, Yaping Ma

Journal of System Simulation

Abstract: To study the avoidance behavior in the evacuation process, a cellular automaton model considering avoidance behavior is established. The model divides the evacuees into avoiders and transferees, and reflects the avoidance behavior by changing the selected probability of evacuees. The impact of the avoidance behavior on the efficiency and evacuation process in different personnel ratios and different initial positions is analyzed. The results show that the avoidance behavior can optimize the evacuation sequence, improve the evacuation efficiency and reduce the risk of evacuation process. The evacuation time is significantly reduced when the probability of avoidance exceeds the thread value, …

Crowd Evacuation Model Based On Improved Pso Algorithm, Changhua Li, Chenggong Bi, Zhijie Li

Journal of System Simulation

Abstract: Aiming at the poor local optimization ability and easy premature convergence of the particle swarm optimization (PSO) algorithm in evacuation simulation, a crowd evacuation model based on the improved PSO algorithm is proposed. On the basis of the original model, factors such as the forward driving force, exclusion driving force and panic degree of evacuees are introduced. According to the environmental factors and crowd movement, evacuees' direction is dynamically adjusted, and tends to the ideal exit under the optimal exit selection mechanism. The parametric simulation experiment of evacuation efficiency is carried out for the physical factors such as the …

A Discrete Krill Herd Algorithm For The No-Wait Flow Shop Scheduling Problem, Changping Liu, Zhenfu Jian, Wenhan Fu

Journal of System Simulation

Abstract: A discrete krill herd algorithm (DKH) is proposed to solve the no-wait flow shop scheduling problem (NWFSP) with the makespan criterion. Based on the characteristics of the optimization mechanism, the notion of “virtual food” in krill herd algorithm and the influenced crossover rules between krill individuals are defined. The concept and calculation method of the individual distance are redefined to measure the neighborhood range to realize the information exchange. The local search strategies of random swap, inverse and insert operator are employed to enhance the local search ability of DKH, and the multiple initialization strategies are redesigned to promote …

3d Reconstruction Of Uav Sequence Image Based On Motion Structure Graph, Yuhao Wu, Xuefeng Cao, Jinchao Peng, Lianrui Xu

Journal of System Simulation

Abstract: UAV sequence image has the characteristics of high overlap and strong topological connection. Aiming at the inefficient and unstable in processing the large-scale UAV images of the existing incremental 3D reconstruction algorithm, a 3D reconstruction method based on motion structure graph is proposed. The image matching index is established by using the geolocation information and IMU data to improve the image matching efficiency, and the random motion consistency algorithm is used to calculate the relative motion; motion structure graph is used to represent the "association" between images, and closed-loop detection algorithm is used to eliminate the false edges. Under …

Modeling And Simulation Of Quadrotor Uav With Vector Thrust Based On Backstepping, Zhou Nan, Wang Liang, Jianliang Ai

Journal of System Simulation

Abstract: Combined with characteristics of the traditional quadrotor and the quad tilt-wing UAV, a quadrotor UAV with the vector thrust (VTQ) is proposed. This UAV has the ability of vertical take-off and landing and hovering, as well as the high maneuverability of the traditional quad tilt-wing UAV. It has the ability of completing the diversified tasks by being specified the desired yaw angle and pitch angle. Control system adopts the method of the layered design. The upper layer is the position control system, the lower layer is the attitude control system, and the control laws are both designed by the …

Research On Modeling Technology For Hard Cutting Process, Caixu Yue, Liu Xin, Jiang Nan, Xianli Liu, Genghuang He, Lingxiang Li

Journal of System Simulation

Abstract: The hard cutting has the features of the high maching flexibility, economical efficiency and environmental friendliness, and is widely used in automobile industry, bearing industry, hydraulic industry, etc. The simulation modeling not only plays an important role in predicting the performance of the hard machining and optimizing machining parameters, but also better reflects the nature of the machining and provides the theoretical guidance to the actual machining. The simulation modeling methods of the hard cutting at home and abroad are introduced, and the chip formation, cutting force, cutting temperature, tool wear and machined surface quality are summarized, and the …