Engineering Commons^™

Analysis Of Static Equilibrium Workspace For Under-Constrainted Cable-Driven System With Multi-Robots, Zhigang Zhao, Li Wei, Youde Li, Yanlin Wang, Ma Yan

Journal of System Simulation

Abstract: For the under-constrainted system that multi-robots tow the payload by cables, which does not meet the condition of force closure and equations are generally not compatible, so the accurate workspace can't be found out. The static equilibrium equation of the system was established, and then the least squares principle combined with the Monte-Carlo method was put forward. When the movement is low speed or quasi static for the payload, the approximate static equilibrium workspace can be found out quickly and the expression of the cable tension is given by using the normal equations and QR decomposition respectively. When position …

Closed-Loop Feedback Simulation To Process Of Ram Blowout Preventer Shut-In Locking, Fangzhou Zhang, Ruixue Sun, Wenjing Zhang, Li Long, Li Qiang

Journal of System Simulation

Abstract: Well control training was explained mainly by teacher in recent years. Virtual simulation made it difficult for students to understand the actual operation. Application of drilling well control simulation training system solved effectively the problem of the scene seldom repetition and high cost of well control training. For the simulation of the process of ram blowout preventer shut-in locking in the well controlled physical simulation training system, the stepping motor driver and the stepping motor were installed in ram blowout preventer, and locking operation of the lock device was realized by using speed and torque of the stepping motor …

Research On Simulation Of Emergency Evacuation Guidance Under Biochemical Terror Attacks, Sui Jie, Shengjie Long

Journal of System Simulation

Abstract: Biochemical terror attacks can cause numerous casualties, especially when it happens in public places such as subway station, which is densely populated, sealed, and complex in topography. And evacuating guidance plays an important role in reducing casualties. A guidance scheme was established based on both evacuating empirical formula and passengers escaping rules, according to evacuation problems in subway station. Meanwhile, the different features of passengers and their behaviors under attack were analyzed, as well as their impacts on evacuation. By simulating various evacuation situations based on social force simulation model, the importance of environmental features and passengers features in …

System Modeling And Simulation For Cylinder Controlled By Servo Valve Of Hydraulic Looper In Hot Strip Mills, Guilin Tao, Weigang Li

Journal of System Simulation

Abstract: Starting from the flow characteristics of cylinder controlled by servo valve of hydraulic looper in hot strip mills, a new mathematic model for hydraulic cylinder controlled by servo valve was established by analyzing and deducing the flow characteristics of two chambers of hydraulic cylinder. The model is different from the traditional equivalent model of “load-pressure flux”, and it is adaptable to many structural forms such as symmetric cylinder, asymmetric cylinder and piston cylinder. The simplified equivalent model was deduced by the simplified method of automatic control principles. The simulation experiments were carried out on a practical cylinder controlled …

Motion Analysis And Simulation Of Lower Limb Based On Adams, Zhang Yan, Haomiao Zhang, Bokai Xuan, Yongchang Zhang

Journal of System Simulation

Abstract: On the basis of the lower limb movement kinematics and dynamics analysis, a lower limb motion simulation system was established by the virtual prototyping technology. The human model was designed by ADAMS and the angle and moment of force in each joint were obtained through kinematics and dynamics analysis. The established model of lower limb was validated by the simulation of human lower limb movement under different road conditions. The experiment result shows that the walking process of each road conditions are stable and normal. It indicates that the virtual prototype model can accurately describe the process of human …

Simulation Of Ultrasonic Shear Wave Imaging In Detection Of Liver Rupture, Yu Jiao, Erwei Nie, Yanying Zhu

Journal of System Simulation

Abstract: Ultrasonic shear wave imaging technology provides the elastic information of the soft tissue by examining the propagation of the shear waves in the tissue. The possibility of using ultrasonic shear wave imaging technology combined with a directional filter for the detection of liver rupture was explored. The COMSOL Multiphysics software was used to simulate the generation and propagation of the shear waves in the liver medium with a rupture, a directional filter-based algorithm was applied to separate the incident wave and reflected wave, and an edge detection algorithm was applied to detect and delineate the liver rupture. Preliminary results …

Simulation-Based Optimization For Site Selection Of Agv Charging Mode, Danlan Xie, Haihong Yu, Chen Jing, Zhipeng Gao, Zhanghao Zhang

Journal of System Simulation

Abstract: With the development of intelligent manufacturing, automation of production line is improving. AGV (automated guided vehicle) as a necessary device in the automation system, it is important to design its charging system. Aiming at the problem of the site selection of online charging, the software FlexSim was used to build simulation model, based on the operation requirements of an actual assembly shop, in an actual planning process. Through a large number of simulation experiments, the maximum stay location of AGV in the different lines was obtained under the influence of random factors. By comparing the idle and blocked …

Simulation Research On Twc Dynamics Model During Cold Starting For Hybrid Electric Vehicle, Deng Tao, Xiaojing Li, Chunsong Lin, Renzhi Lu

Journal of System Simulation

Abstract: To reduce the emissions for gasoline engine during cold starting, the influences of crevice effect, wet wall effect because of the low cylinder temperature, adsorption/desorption of cylinder oil film and incomplete combustion on the HC emissions were analyzed. Moreover, the influences of the storage and release of oxygen on effective oxygen concentration were considered. The three-way catalytic (TWC) model was established with the lumped parameter method and analyzed under NEDC cycle. The temperature of exhaust gas getting in and out of the catalytic converter, the quantity and the efficiency curve of emissions were obtained. Furthermore, the conversion efficiency …

Simulation Research On Electromagnetic Radiation Noise Of Pantograph Arc, Fengyi Guo, Xili Wang, Xingbang Hu, Zhiyong Wang, Yanli Liu

Journal of System Simulation

Abstract: Pantograph-catenary system electromagnetic noise radiation not only endangers traffic safety, but also adversely affects the health of nearby residents and communications along the railway. By studying the radiation characteristics of the electromagnetic noise of the pantograph-catenary, provide a theoretical basis for suppression its radiation intensity. A Matlab simulation model of the pantograph offline arc was established, the simulation result shows out the discharge characteristics and the spectrum bounds of the arc. Then using the finite element analysis software to do a simulation analysis about pantograph typical frequency of the arc, the far-field and near-field characteristics based on the pantograph …

Reconfigurable Rtgpu's Architecture And Simulation, Xiaopeng Cao, Jungang Han

Journal of System Simulation

Abstract: Although GPU has developed rapidly, the core still uses rasterization and it is a hard problem for the complex scene. The ray tracing can simulate the geometrical optics and get the better effect, but it needs the amounts of computing power. Thus, the characteristic of the ray tracing was studied and the new pipeline was designed. A dynamic reconfigurable hardware architecture (RTGPU) was put forward mapping the pipeline to it. A simulation platform was designed. According to results of experiments, more than 11x on RTGPU could be gained achieving the better performance than GPU.

Optimization Design And Simulation Of Washout Algorithm For Flight Simulator, Wang Hui, Daoyang Zhu, Xiaojing Fu

Journal of System Simulation

Abstract: The key of the fidelity of flight simulators lies in the merits of the washout algorithm; the classical washout algorithm has been widely applied owing to its convenient parameter adjustment as well as rapid feedback and execution speed. However, the classical washout algorithm still exists some certain defects in its structure design, which will cause exaggerated phase retardation error and false cues thus resulting in the deterioration in dynamic fidelity of flight simulators. According to vestibular perception system, the structure redesign of the classical washout algorithm was carried out, using the compensation theory to reduce its phase retardation and …

Study On Pulverizing System Simulation Model Of 300mw Lignite Oxygen-Enriched Combustion Boiler, Jianqiang Gao, Shaodong Sun

Journal of System Simulation

Abstract: The simulation model of the pulverizing system of a 300 MW lignite oxygen-enriched combustion boiler was developed. And the dynamic and static simulation experiments were completed, the experiments included lignite surface moisture content variation, disturbance of feeder norm speed, flue gas inlet temperature and flow rate etc. The results show that, the model is able to correctly simulate the dynamic process of the system. Moisture reduction has a larger impact on the pulverizing system operating parameters. The mill outlet temperature gets a significant rise, especially when it is less than 30%. When the feeder norm speed or flow rate …

Research Of Vibration Control On Nonlinear Rotor System With Fuzzy-Pid, Liu Jun, Zhenwang Liu, Jianen Chen, Liangfu Wang

Journal of System Simulation

Abstract: In order to overcome the problems which are the model of the nonlinear restoring force and the nonlinear vibration control, the vibration control of the nonlinear rotor system and the processing the nonlinear restoring force were accomplished based on the electromagnetic actuator using the FUZZY-PID controller with the fitness function of the variable width and variable geometric shapes. Using the Jeffcott rotor model with the nonlinearities of the forces of the bearing and the electromagnetic actuator, the simulations of the vibration control on the rotor system were performed. Through comparing with the control methods of the traditional PID and …

Stability Analysis Of Systems With Time Delay Simulation Program, Matthew Carroll, Brandon Replogle

Electrical Engineering

A small company wants to develop a CAD tool, ideally as part of the MATLAB suite of tools, for system stability analysis of nonlinear control systems with time-delay. The program must allow the designer to input the system block diagram graphically, then using symbolic expansion, automatically generate the Laplace domain stability boundary and disturbance settling time. The stable regions are then to be graphically plotted as a set of 2- or 3-dimensional parametric stability boundaries. The designer can then input performance constraints on the system through the MATLAB console and a Simulink environment will automatically be generated.

This program is …

Improved Design Scheme And Simulation Analysis Of Non-Valve Controlled Hydraulic Impact System, Liu Zhong, Zou Yu, Zhang Kai, Zhao Fei, Junjun Liu

Journal of System Simulation

Abstract: Due to valve port commutation of traditional hydraulic impact system caused valve leakage. For the above shortcomings, an improved structure principle of the new type of non-valve controlled hydraulic impact system was proposed establishing dynamic equations of impact system andconducting simulation analysis based on AMESim. Due to the simulation results which was inconsistent with design goal, two improvement schemes were proposed adding throttle device and controlling inlet and outlet circuit. The simulation results suggest that the working performance of impact system has been improved by adding throttle device, and its efficiency has been increased from 11.8% to 18.3% …

Modeling And Simulation Of Power Communication Networking Based On Quality Of Service, Xueyi Zhang, Juhui Gu, Meiqin Zhou

Journal of System Simulation

Abstract: For the complex network topology and channel time-varying characteristics of power line carrier communication in low voltage distribution grid, there is a phenomenon of slow convergence and stagnation when solving the routing problem with traditional ant colony algorithm. The algorithm used is easy to fall into premature and local optimization. An automatic networking algorithm based on transmission delay and the load factor of the evaluation factors was proposed and a genetic algorithm was joined at a later stage. The optimal solution was obtained by using the improved crossover operators, and the convergence of optimal algorithm solution was accelerated by …

Design For Additive Manufacturing, Michael Charonnat, Leonardo Franco-Muñoz, Sam Noble, J.P. Purdom

Mechanical Engineering

This document outlines the critical design details and timeline for the Design for Additive Manufacturing Senior Project sponsored by Solar Turbines, Inc. The scope of this project encompasses the redesign of two of Solar Turbine’s cast parts for metal additive manufacturing in order to minimize lead time, cost, and weight. With the overall objective of performing in-depth analysis exploring affordability & feasibility, this redesign process will aid Solar Turbines in expanding their knowledge of Design for Additive Manufacturing principles and enable them to further incorporate the use of additive manufacturing into their production processes. The first part that the team …

Simulation And Analysis Of Ultra High Frequency Induction Heating Circuit Based On Current Source, Mangyuan Ma, Xinchun Shi, Wang Hui, Jianhui Meng

Journal of System Simulation

Abstract: The operating frequency range, operating mode and output power are determined by the circuit. A suitable circuit is very important for induction heating power supply. On the basis of Class-E and Boost Chopper circuit, a new current source was analyzed with parallel resonant load circuit by energy conservation law and Fourier decomposition, which derived mathematical relation among the parameters and provided application theory. This circuit was studied by using Matlab/Simulink with variable parameters, which obtained the operating waves with different parameters and values. Comparing the operating waves with the theoretical analysis, the simulation results are completely consistent with the …

Development Of Reduced Chemical Kinetic Models For The Numerical Simulation Of Combustion And Emissions Behavior Of Representative Conventional And Bio-Derived Fuels, Mazen A. Eldeeb

Mineta Transportation Institute

The study addresses two of the main challenges facing combustion modeling for transportation fuels: simultaneous simulation of non-related combustion problems and reducing the computational cost of the modeling process itself. To address the first challenge, researchers determine a characteristic flame time from thermal diffusivity and laminar burning velocity. Researchers examine parametric dependence of flame time and ignition delay time on pressure, temperature and equivalence ratio for methane, based on validated chemical kinetic mechanisms. The study reveals flame time and ignition delay time show similar temperature dependence, flame time has stronger dependence on equivalence ratio and weaker dependence on pressure than …

Evaluating Driving Performance Of A Novel Behavior Planning Model On Connected Autonomous Vehicles, Keyur Shah

Honors Scholar Theses

Many current algorithms and approaches in autonomous driving attempt to solve the "trajectory generation" or "trajectory following” problems: given a target behavior (e.g. stay in the current lane at the speed limit or change lane), what trajectory should the vehicle follow, and what inputs should the driving agent apply to the throttle and brake to achieve this trajectory? In this work, we instead focus on the “behavior planning” problem—specifically, should an autonomous vehicle change lane or keep lane given the current state of the system?

In addition, current theory mainly focuses on single-vehicle systems, where vehicles do not communicate with …

Force/Position Hybrid Control Method For Surface Parts Polishing Robot, Yufeng Ding, Xinpu Min

Journal of System Simulation

Abstract: A force/position hybrid control method for polishing the complex surface with an industrial robot is put forward. The method can achieve the stable force control and precise position control to ensure the consistency of the material removal rate at different normal vectors. After the trajectory of the normal vector is planned in CAD software, the force signal feedback from the sensor and the PI controller in the normal vector direction are combined,and the robot end tool corrects the motion trajectory in the vector direction of the surface to indirectly control the contact force between the tool and the surface. …

A Quantile-Based Approach For Transmission Expansion Planning, Jairo Cervantes, F. Fred Choobineh

Department of Electrical and Computer Engineering: Faculty Publications

Transmission expansion planning is an integral part of power system planning and consists of generating and selecting transmission proposals for maintaining sufficient transmission capacity to satisfy the electric load. Specifically, the desire to increase the use of renewable energy has exposed the limitations of transmission networks and has elevated the importance of transmission expansion planning. However, considering the random nature of renewable sources in conjunction with the power outages makes the planning process very challenging. We present a new procedure for selecting the best transmission enhancement proposal from a set of finite proposals under uncertainty. The selection is based on …

An Agent-Based Model To Study Competitive Construction Bidding And The Winner's Curse, Amr Elsayegh, Cihan H. Dagli, Islam H. El-Adaway

Engineering Management and Systems Engineering Faculty Research & Creative Works

Reverse auction theory is the basis for competitive construction bidding process. The lowest bid method is utilized for selecting contractors in public projects. The winning contractor having the lowest bid value could be cursed when the submitted bid value results in negative profits. This is caused by many factors such as the contractor's estimation accuracy and markup. This is addressed in this paper by providing a model simulating the construction competitive bidding and the occurrence of the winner's curse. To this end, the authors show the extent to which the winner's curse affects the status of contracting companies. The objectives …

Robust, Time-Critical, Evidence-Based Adaptive Data Fusion, Mohammad Amin Javadi

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Sensors have become inevitable part of many studies and working areas ranging from navigation, transportation and medical applications. A sensor can help a user in a variety of situations including dangerous, inaccessible, time and money-consuming circumstances. Applying multiple sensors simultaneously allows for improving the accuracy of measurement estimates for system states. As an example, a part of this study uses a GPS sensor to increase the accuracy of the position estimation obtained by an IMU in an indoor environment. The same GPS device with position outputs can also be studied to provide a new measuring dimension such as velocity. This …

A Simulation Approach To Evaluate The Impact Of Breast Cancer Overdiagnosis On Patient Outcomes, Sierra Wagner

Industrial Engineering Undergraduate Honors Theses

Breast cancer overdiagnosis risk is difficult to estimate and varies significantly across current research. This research establishes a simulation approach to examine the relationship between breast cancer overdiagnosis and patient outcome and understand the impact that the range of breast cancer overdiagnosis rate estimates in the current literature has on patient outcomes. Overdiagnosis is represented in this study by a set of disease regression probabilities. Using microsimulation, we evaluate patient outcome, measured by number of mammograms and lifetime breast cancer mortality risk, as a function of treatment policy and regression probability. We use numerical experiments to evaluate treatment policies and …

Impact Of Large-Scale Correlated Failures On Multilevel Virtualized Networks, Max G. Medina, Mohammed J.F. Alenazi, Egemen K. Cetinkaya

Electrical and Computer Engineering Faculty Research & Creative Works

Communication network architectures have been evolving with increased programmability and virtualization of physical infrastructures. While this evolution enables a faster introduction of new services and efficient utilization of resources, the complexities and interdependencies among the physical and virtual infrastructures, as well as the control and management planes, hinder a complete understanding of the system at hand. It is imperative, therefore, to model and study these evolving virtualized infrastructures. We propose a multilevel virtualized network embedding model and study its performance against correlated failures. Our analysis of multiple synthetic network models identified that grid-like infrastructures capture the realistic Internet2 structure the …

Optimization And Simulation Models To Improve Access To Organ Transplantation In The United States., Fatemeh Karami

Electronic Theses and Dissertations

Organ allocation in the U.S. is administrated by the United Network of Organ Sharing (UNOS). UNOS’s mission is to ensure fair and equitable allocation of organs as stated in the Code of Federal Regulations, which reads "neither place of residence nor place of listing shall be a major determinant of access to transplant". Despite the regulations, there has been endless controversy surrounding the disparity in access to organ transplants. In this context, the primary research goal in this dissertation was to reduce geographic disparity in access to transplants in the U.S., with a focus on heart and kidney transplants. To …

Impact Of Magnetocaloric Material Properties On Performance Of A Magnetocaloric Heat Pump., Michael G. Schroeder

Electronic Theses and Dissertations

In the field of magnetocaloric heat pumps much research has been performed around machine design and theoretical machines, but little has been researched around practical problems such as variability in material properties. The present work defines a simulation tool that has been proven with experimental data. Magnetocaloric material cascades were statistically analyzed and parameterized, such that they could be recreated parametrically using a split Lorentz function with normally distributed parameters. Correlated curve-defining values with standard deviations were used as input into the simulation tool to determine the effect of variation on cooling heat pump performance for a household refrigerator application. …

Discrete Vortex Modeling Of Aerodynamic Flutter Of A Flat Plate With Damped Oscillations, Emma Chao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aerodynamic flutter is the unstable oscillation of a body caused by the interaction of aerodynamic forces, structural elasticity, and inertial effects induced by vortex shedding. Current models of this phenomenon require finite element analysis and extensive computational power and processing time. The purpose of this study was to develop and validate a program that is faster and more efficient than existing approaches by using the discrete vortex method (DVM). By reducing the complexities of flutter to the shedding of vortices in an inviscid model of a two-dimensional flat plate with a torsional spring constant at its center, this phenomenon can …

An Exploratory Study Of Us Navy T-45c Simulation Training, Aaron D. Judy Ed.D., Tom Gollery Ed.D.

Journal of Applied Social Science Research and Practice

Flight training is costly and workload intensive. According to a recent Government Accountability Office (GAO) report, the US Navy and US Air Force predict a 25% shortage of fighter pilots by 2023 (GAO, 2018). The military needs empirical research to determine the effectiveness of flight simulation training and whether simulation training can decrease the overall training time for student pilots. The purpose of this study was to compare intermediate and advanced military student pilots’ scores on the T-45C OFT simulator training events and scores on the T-45C aircraft training events in four training domains; the intervention in this study included …