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Full-Text Articles in Engineering
Simulation Research On Twc Dynamics Model During Cold Starting For Hybrid Electric Vehicle, Deng Tao, Xiaojing Li, Chunsong Lin, Renzhi Lu
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
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 …
Research Of Vibration Control On Nonlinear Rotor System With Fuzzy-Pid, Liu Jun, Zhenwang Liu, Jianen Chen, Liangfu Wang
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 …
Reconfigurable Rtgpu's Architecture And Simulation, Xiaopeng Cao, Jungang Han
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
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
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 …
Modeling And Simulation Of Power Communication Networking Based On Quality Of Service, Xueyi Zhang, Juhui Gu, Meiqin Zhou
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 …
Improved Design Scheme And Simulation Analysis Of Non-Valve Controlled Hydraulic Impact System, Liu Zhong, Zou Yu, Zhang Kai, Zhao Fei, Junjun Liu
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% …
Simulation And Analysis Of Ultra High Frequency Induction Heating Circuit Based On Current Source, Mangyuan Ma, Xinchun Shi, Wang Hui, Jianhui Meng
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 …
Force/Position Hybrid Control Method For Surface Parts Polishing Robot, Yufeng Ding, Xinpu Min
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. …
An Agent-Based Model To Study Competitive Construction Bidding And The Winner's Curse, Amr Elsayegh, Cihan H. Dagli, Islam H. El-Adaway
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 …
A Simulation Approach To Evaluate The Impact Of Breast Cancer Overdiagnosis On Patient Outcomes, Sierra Wagner
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 …
Robust, Time-Critical, Evidence-Based Adaptive Data Fusion, Mohammad Amin Javadi
Robust, Time-Critical, Evidence-Based Adaptive Data Fusion, Mohammad Amin Javadi
Industrial, Manufacturing, and Systems Engineering Dissertations
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 …
Optimization And Simulation Models To Improve Access To Organ Transplantation In The United States., Fatemeh Karami
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 …
One Design Mode Of Highly Configurable Modular Simulation System, Chunsheng Hu, Chengdong Xu, Penfei Zhang
One Design Mode Of Highly Configurable Modular Simulation System, Chunsheng Hu, Chengdong Xu, Penfei Zhang
Journal of System Simulation
Abstract: The computer simulation technology is an essential verification way to the design, construction and application optimization of the modern complex system. Following the continuous growing complexity of the system, the higher requirement on the configurability of the simulation system is needed to face the rapidly change. Based on the analysis on the configurability and some coupling factors with the adverse effect, a design mode of highly configurable and open and easy to expend modular simulation system is proposed. The results show that, despite the cost of some real-time performance, the design mode can realize the high configurability of the …
Validation Risk Across Hierarchical Models, John B. Young
Validation Risk Across Hierarchical Models, John B. Young
Computational Modeling & Simulation Engineering Theses & Dissertations
Modeling and simulation are applied in a great many methods across a variety of topics. Model developers and users alike have a professional duty to understand the complexities of the tools and methods they are used. Oftentimes, models that have been independently constructed and executed are used to inform one another for an analytic purpose and the compatibility of the models is not always addressed. In the literature, great attention has been paid to model validation. When using models constructively with one another, analysts must understand the bounds of model validity and ensure that the combination of models does not …
Simulation Analysis On Flexible Track Drilling Machine Based On Adams, Yanchao Zhang, Ting Wang, Danlong Song
Simulation Analysis On Flexible Track Drilling Machine Based On Adams, Yanchao Zhang, Ting Wang, Danlong Song
Journal of System Simulation
Abstract: The three-dimensional model of the flexible track drilling machine is designed by the virtual prototyping technology. The model is imported into ADAMS (Automatic Dynamic Analysis of Mechanical Systems) software to carry out the kinematics and dynamic simulation analysis of its virtual prototype, and the rationality and feasibility of the system design are evaluated. Through the comparative analysis, the reasonable driving velocity and acceleration parameters of the hole making system are given. According to the analysis of the dynamic characteristics of the systems, the asymmetric driving problems in the system are found and the corresponding improvement scheme is put forward. …
Emergency Evacuation Simulation For Dense Passenger Flow In A Rail Transit Transfer Station, Xu Hui, Tian Cheng, Wang Yong
Emergency Evacuation Simulation For Dense Passenger Flow In A Rail Transit Transfer Station, Xu Hui, Tian Cheng, Wang Yong
Journal of System Simulation
Abstract: The rail transit is one of the important modes of the public transportation, and its safety operation is crucial. Based on the passenger volume and structure features that have been obtained through the field investigation in Chongqing Lianglukou railway station in China, a multi-level rail transit transfer station simulation model is built to analyze the evacuation process of pedestrians in the consideration of explosion and other emergencies by the software AnyLogic. The evacuation routes and evacuation time of passengers during emergency evacuation in a rail transit transfer station are studied. The research aims at verifying the emergency evacuation capacity …
Design Of Air Defense Missile Weapon System Simulation Platform Based On Xsim Platform, Kaizhi Ruan, Qingqing Yuan, Wenhua Zhai, Zhiqiang Zhang
Design Of Air Defense Missile Weapon System Simulation Platform Based On Xsim Platform, Kaizhi Ruan, Qingqing Yuan, Wenhua Zhai, Zhiqiang Zhang
Journal of System Simulation
Abstract: Taking the system simulation technology which applied to the scheme argumentation, optimization design, flight test forecast, battle effectiveness evaluation of air defense missile weapon system as background, the design method of air defense missile weapon system simulation platform based on Xsim platform was put forward. The total configuration design, model design and simulation process design of the platform were discussed. An simulation platform of an air defense missile weapon system was accomplished. The result proves the platform can simulate the battle process of air defense missile weapon system, support the simulation work of air defense weapon at different …
Energy Forensics Analysis, Rupa Das
Energy Forensics Analysis, Rupa Das
Graduate Theses, Dissertations, and Problem Reports
The energy consumed by a building can reveal information about the occupants and their activities inside the building. This could be utilized by industries and law enforcement agencies for commercial or legal purposes. Utility data from Smart Meter (SM) readings can reveal detailed information that could be mapped to foretell resident occupancy and type of appliance usage over desired time intervals. However, obtaining SM data in the United States is laborious and subjected to legal and procedural constraints. This research develops a user-driven simulation tool with realistic data options and assumptions of potential human behavior to determine energy usage patterns …