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Full-Text Articles in Engineering
Research On Recovering Of Complex Networks Based On Boundary Nodes Of Giant Connected Component, Zhe Wang, Jianhua Li, Kang Dong
Research On Recovering Of Complex Networks Based On Boundary Nodes Of Giant Connected Component, Zhe Wang, Jianhua Li, Kang Dong
Journal of System Simulation
Abstract: Network recovery is an important way to solve the inevitable failure,and the reasonable recovery strategy can reduce the cost of resource and improve the network robustness.In order to study the dynamic behavior of recovery process and the relationship between recovery and network robustness,a Recovery Model of Boundary Nodes (RMBN) based on boundary of giant connected component is proposed,and two network Recovery strategies,Average Recovery of Boundary Nodes (ARBN) strategy and Priority Recovery of Boundary Nodes (PRBN) strategy are designed.The simulation results of different recovery strategies on three network models show that with the increase of recovery ratio,the …
One Turbulent Modeling Method Based On Environmental Forecast Data, Dawei Fan, Jiahui Tong
One Turbulent Modeling Method Based On Environmental Forecast Data, Dawei Fan, Jiahui Tong
Journal of System Simulation
Abstract: Based on the existing natural environment model of aircraft simulation test,the method of conversion and processing for environmental prediction data is studied.Based on the random wave theory,the mathematical model of turbulent wind is established,and the simulation modeling method is studied.Based on Davenport spectrum,a turbulent wind model based on environmental prediction data is established and is introduced into the mathematical simulation experiment of a type of aircraft to obtain the influence of wind turbulent on the flight state of the aircraft.The experimental results show that the gust turbulence has a greater impact on the aircraft's angle of …
Controller Design For Hypersonic Vehicle Based On Kalman Filter, Tao Chao, Jianliang Ai
Controller Design For Hypersonic Vehicle Based On Kalman Filter, Tao Chao, Jianliang Ai
Journal of System Simulation
Abstract: For a generic hypersonic vehicle with unstable longitudinal and lateral-directional mode, considering the three dimensional turbulence and their gradient, all states linear dynamic equations were established. All states H∞ feedback control was proposed based on the discrete Kalman filter when three dimensional turbulence and system measurement noise were taken into consideration. In this way, state estimation created by the Kalman filter to the H∞ controller was delivered. This method could guarantee the robustness when external atmospheric turbulence and itself parameter matrices perturbation caused by the flight condition variation existed. The results show that for both the nominal …
Research On Evolution Modeling Of Complex Network Based On Priority Of Equipment Capability, Fengqin Zhang, Liang Dong, Guan Hua, Dawu Chen, Xiaoqing Li, Qingfeng Zhang
Research On Evolution Modeling Of Complex Network Based On Priority Of Equipment Capability, Fengqin Zhang, Liang Dong, Guan Hua, Dawu Chen, Xiaoqing Li, Qingfeng Zhang
Journal of System Simulation
Abstract: According to disadvantages of the traditional approaches of complex modeling for description of weapons and equipment on dynamic and uncertainty, referencing to the OODA theory, a new approach for evolution modeling of combat system complex network was put forward based on priority of equipment capability, which had improved BA scale-free networks model by the process of choosing linking objects, defining link edges, backing out of combat nodes and dynamic adjusting to the modeling policy based on the capability values of each nodes of weapon and equipment under particular applications. By simulation experiments, the new approach, which has the features …
Nonlinear H∞ Control For Marine Speed With Parameter Perturbation And Ambient Interference, Yupeng Yuan, Zhang Meng, Xinping Yan, Guo Bo, Jianglong Wan
Nonlinear H∞ Control For Marine Speed With Parameter Perturbation And Ambient Interference, Yupeng Yuan, Zhang Meng, Xinping Yan, Guo Bo, Jianglong Wan
Journal of System Simulation
Abstract: In order to improve the automation level and enhance the navigation safety of ships, stable control for ship speed is very important. Good control effect is difficult to obtain based on the conventional control method since the marine speed control system is a time-varying parameters and nonlinear complicated propulsion system. The uncertainty of the system parameters and the effect of environment such as winds, waves and currents were considered adequately in ship motion mathematical model with disturbing force. The mathematic model was linearized accurately with the differential geometry method. Then the nonlinear H∞ controller was designed according to …
Robust Steerable Frequency Invariant Beamformer Design Based On Srv-Cls, Suting Chen, Zhang Wei
Robust Steerable Frequency Invariant Beamformer Design Based On Srv-Cls, Suting Chen, Zhang Wei
Journal of System Simulation
Abstract: The frequency invariant beamformer (FIB) has important applications in wideband array signal processing. Conventional FIB design approaches are usually proposed without considering the mismatches in microphone array characteristic, which leads to the performance of the FIBs degrading in practical applications. Therefore, a robust steerable frequency invariant beamformer design approach based on spatial response variation constrained least squares (SRV-CLS) was proposed. It combined the SRV-CLS FIB design approach with classical robust beamforming algorithm, and added the microphone characteristics as robust favor in the cost function. The proposed approach could work well in the presence of microphone mismatches, ensured the frequency …
Broadband Beamforming Method For Circular Sensor Array, Gan Tian
Broadband Beamforming Method For Circular Sensor Array, Gan Tian
Journal of System Simulation
Abstract: The beamforming method based on mode decomposition is a kind of very good beamforming method for circular sensor arrays, in order to apply it to the broadband beamforming, An against white noise robust beamforming method was proposed to design an expect beam. The method designed the modal domain robust modal coefficient using the model decomposition method to generate different beam under the different mode circumstances, using second-order cone optimization algorithm gain more reasonable compromise than the other methods in the broadband beam performance, The platform of choice and operation of space were provided according to the demand for …
Robustness Research For Adaptive Control Algorithms Of Pipe Conveying Fluid Vibration, Chen Bing, Yuanyuan Huang, Zhongjun Yin
Robustness Research For Adaptive Control Algorithms Of Pipe Conveying Fluid Vibration, Chen Bing, Yuanyuan Huang, Zhongjun Yin
Journal of System Simulation
Abstract: Pipes with supported ends may lose their dynamic stability due to parametric instability when they convey pulsating fluid. the piezoelectric actuators were taken as the control actuators, and built a controlling mathematical model of the pipeline system. Then aiming at the traditional PID controller’s poor robustness on pipeline system parameters, MRAC system and MRAC system based on adaptive gain of the PD were designed on the basis of Lyapunov stability theory, not only the vibration peak values of the pipeline system were suppressed in a short time, but also the controllers had better robustness on pipeline system parameters. Control …
Two Image Watermarkingmethodsbased On Compressive Sensing, Yidi Miao, Lü Ju, Xiumei Li
Two Image Watermarkingmethodsbased On Compressive Sensing, Yidi Miao, Lü Ju, Xiumei Li
Journal of System Simulation
Abstract: As an emerging sample theory, compressive sensing attracts wide attention because it breaks through the Nyquist sampling theorem. , Two different methods of watermark embedding and extraction are presented by measuring the carrier image and watermark image respectively based on compressive sensing. Moreover, the attack tests, such as the Gaussian noise, pepper and salt noise, filtering, compression, and cropping, are implemented to watermarked images. Experiment results show that although the two different methods for image watermarking have different processing procedure, both can guarantee the robustness and security of embedded digital watermark.
System-Of-Systems Combat Ooda Loop Robustness Modeling And Experiment, Mingzhi Zhang, Ma Li
System-Of-Systems Combat Ooda Loop Robustness Modeling And Experiment, Mingzhi Zhang, Ma Li
Journal of System Simulation
Abstract: It is a difficult issue to design metrics of measure of the OSOS capabilities, which are emergent properties of OSOS. The concept of the OODA loop robustness was proposed and it was closely related to the overall capabilities of OSOS. A new method to measure the OODA loop robustness was discussed. The OSOS combat network mode was established l. Based on the weighted network, the Perron-Frobenius Eigenvalue (PFE) of the adjacency matrix of the network was used to measure the OODA loop robustness. Simulations show that there is a strong correlation between the PFE and the metric …