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Full-Text Articles in Physical Sciences and Mathematics

Evaluation Method Of Training Simulation Result Based On Grey Clustering And Analytic Hierarchy Process, Zhaobin Wu, Chen Li, Chunxia Zhao Aug 2020

Evaluation Method Of Training Simulation Result Based On Grey Clustering And Analytic Hierarchy Process, Zhaobin Wu, Chen Li, Chunxia Zhao

Journal of System Simulation

Abstract: An evaluation method based on grey relational analytic hierarchy process was proposed in order to improve rationality of evaluation training result of portable anti-air missile training simulation system. The evaluating indicators including definitions and calculation equations were proposed from three aspects including accuracy, rapidity and stationarity. The weights of the evaluating indicators were calculated by analytic hierarchy process of multiple experts, and the scores of the evaluating indicators were given by 0-1 process and grey clustering evaluation, and using the weights and scores of the evaluating indicators the training score could be obtained. An example of evaluation training result …


Research And Simulation On Trajectory Control Of Telescopic Boom Aerial Work Platform For Hull Spray Painting, Wang Xin, Lingchong Gao, Zhaoqiu Huang, Yuchen Xiao Aug 2020

Research And Simulation On Trajectory Control Of Telescopic Boom Aerial Work Platform For Hull Spray Painting, Wang Xin, Lingchong Gao, Zhaoqiu Huang, Yuchen Xiao

Journal of System Simulation

Abstract: Telescopic boom aerial work platform, which has been widely applied in ship building field, is taken as research object. An intelligent method of spray painting, continuous spray painting along hull's contour was proposed. Correspondence between position vector of boom's top and drive-space vector was established. A path planning strategy of continuous spray painting was designed, and the variation of driving-space vector was acquired when the path was known. The trajectory control system of intelligent spray painting was modeled in Simulink environment based on the transfer function of electro-hydraulic proportional position control system. The correction link made of …


Invasive Weed Optimization Algorithm Combined With Chaotic Mutation And Analysis Of Its Property, Huang Xia, Chunming Ye, Cao Lei Aug 2020

Invasive Weed Optimization Algorithm Combined With Chaotic Mutation And Analysis Of Its Property, Huang Xia, Chunming Ye, Cao Lei

Journal of System Simulation

Abstract: Inspired by the reproductive aggressive behavior of weeds in nature, invasive weed optimization algorithm (IWO) was developed as a novel bionic swarm intelligence optimization algorithm. An improved IWO algorithm was proposed on the basis of analyzing bionic principle and limitations of basic IWO, which applied an initialization strategy based on chaotic opposition-based learning, increased the diversity of the population through the mutation operator, and enhanced its ability to jump out of local optimal value by chaotic search around current elites. Simulation results for benchmark functions show that the proposed algorithm has improved optimization property compared with IWO, as an …


Improved Genetic Algorithm-Based Network Game Path Selection And Simulation, Jianping Gu, Mingmin Zhang, Meiliang Wang Aug 2020

Improved Genetic Algorithm-Based Network Game Path Selection And Simulation, Jianping Gu, Mingmin Zhang, Meiliang Wang

Journal of System Simulation

Abstract: Traditional optimal path algorithm only sets the shortest path as the target, and it does not consider the network congestion and the number of users in game area for real-time situation, thus resulting in some limitations. According to the actual circumstance of network game, network game path selection model was proposed, and the improved genetic algorithm was employed for simulation. The method pre-processed the game map to get each road weighted length value for a real-time game map, and optimization solution was obtained through the genetic algorithm. A network game path selection method based on improved genetic algorithm was …


Simulation Research On Wireless Power Transmission System Of Cardiac Pacemaker Based On Magnetic Resonance, Xiuquan Liu, Yanhong Li, Huang Ping Aug 2020

Simulation Research On Wireless Power Transmission System Of Cardiac Pacemaker Based On Magnetic Resonance, Xiuquan Liu, Yanhong Li, Huang Ping

Journal of System Simulation

Abstract: Aiming at disadvantages of the battery limited supply time of the implantable cardiac pacemaker and the actual application of electromagnetic induction wireless power transmission (WPT) system, the resonant WPT technology was proposed. The basic working principle of a WPT system of the implantable cardiac pacemaker was introduced. Based on Magnetic resonance coupling and mutual inductance calculation model, the mathematics models of the WPT system of the cardiac pacemaker were established. By the accurate formulae of the mutual inductance of the primary and secondary coreless coils, the influences of the parameters, such as the axial distance, radial offset and coli …


Virtual Reality Game For Head Rehabilitation Based On Kinect, Shutao Shen, Gao Fei, Xu Ning Aug 2020

Virtual Reality Game For Head Rehabilitation Based On Kinect, Shutao Shen, Gao Fei, Xu Ning

Journal of System Simulation

Abstract: The application of virtual reality in the rehabilitation has been extensively studied, which helps patients after a stroke independently perform daily living activities, while saving time, money and other costs. This study used Microsoft Kinect virtual reality game to assess the movement of the users. The game required movement outside of the head, torso and arms. In nine games exercise, the average and maximum amount of movement remained unchanged. However, with the increase of exercise, the frequency of head movement increased. The results show that by head movement, video games can be used to balance the posture rehabilitation, …


Facial Vital Sign Based Countermeasure Against 3d Mask Attacks, Xiaojing Gu, Chuanqing Fu, Xingsheng Gu Aug 2020

Facial Vital Sign Based Countermeasure Against 3d Mask Attacks, Xiaojing Gu, Chuanqing Fu, Xingsheng Gu

Journal of System Simulation

Abstract: Vulnerability to spoofing attacks is the main drawback for current face authentication systems. Traditional spoofing attacks include displaying printed photos and replaying recorded videos. With the development of 3D printing technology, the 3D mask spoofing attack has been becoming the new threat. A novel anti-spoofing feature was proposed to 3D mask attacks. A liveness feature from the power spectrum of facial color signal was extracted based on a physiological phenomenon that the color of real human face changed periodically due to the blood circulation. The performance of countermeasure jointly using the liveness feature and facial texture feature was evaluated …


Research On Direct Torque Control Of Induction Motor Based On Svpwm, Yougui Guo, Dongqing Pan, Deng Cheng, Li Hui, Wenlang Deng Aug 2020

Research On Direct Torque Control Of Induction Motor Based On Svpwm, Yougui Guo, Dongqing Pan, Deng Cheng, Li Hui, Wenlang Deng

Journal of System Simulation

Abstract: The traditional direct torque control of induction motor directly controls the flux and torque through hysteresis comparator, which leads to problems such as limited voltage control vectors, large flux and torque ripple. To solve the problems, adopting SVPWM-DTC, a direct toque control (DTC) method based on space vector pulse width modulation (SVPWM) was verified with a simulation. The results show that this method can improve the performances of DTC system efficiently and maintain the switch frequency constant at the same time. A practical application used in variable speed constant frequency double-fed wind power system was proposed, in which the …


Novel Modeling Of Memristive Cellular Neural Network And Its Circuit Simulation, Xiaohong Zhang, Linyu Liao, Lianghua Yu Aug 2020

Novel Modeling Of Memristive Cellular Neural Network And Its Circuit Simulation, Xiaohong Zhang, Linyu Liao, Lianghua Yu

Journal of System Simulation

Abstract: The memristor as the fourth fundamental circuit component included along with the resistor, capacitor and inductor could simulate the storage memory function of brain neural network. A traditional three-dimensional CNN was designed, and the output function was implemented with the nonlinear characteristics of a flux-controlled memristor. The conventional electronic devices in Multisim were utilized to simulate flux-controlled memristor which simplified the output function part of the circuits. To compare with the CNN system which has chaotic behaviors, the circuits of novel memristive cellular neural network not only can show a chaos attractors phenomenon, but also the inner magnetic energy …


Prediction Of Energy Efficiency Of Nc Machine Tools Based On Recursive Method With Discounted Measurements, Cai Lei, Wang Yan, Zhicheng Ji Aug 2020

Prediction Of Energy Efficiency Of Nc Machine Tools Based On Recursive Method With Discounted Measurements, Cai Lei, Wang Yan, Zhicheng Ji

Journal of System Simulation

Abstract: Aiming at the problem that the energy efficiency of numerical control machine tool is difficult to obtain directly, a new method combined with the recursive method with discounted measurements was presented to predict the energy efficiency of machine tool. The estimation model of the cutting power was given in view of the power balance equation of the machine tool main drive system and the additional load loss function, further taking into account the additional load loss coefficients in model could not be directly measured, the recursive method with discounted measurements was adopted to identify the additional load loss coefficients …


Calculation Of Transformer Core Loss Based On Finite Element Coupling Algorithm, Yongqiang Wang, Zhihong Zheng, Baolong Ouyang, Jianfang Li Aug 2020

Calculation Of Transformer Core Loss Based On Finite Element Coupling Algorithm, Yongqiang Wang, Zhihong Zheng, Baolong Ouyang, Jianfang Li

Journal of System Simulation

Abstract: In order to accurately calculate the deducting transformer core loss, on the basis of analysis on traditional finite element method and Steinmetz method, an edge-nodal coupled $E-\psi$ method was proposed to calculate the High Power High Frequency High Voltage transformer core loss. Taking a 20 kHz, 50 kV, 60 kW transformer for example, the 3D model was established to calculate the transformer core loss. By comparing the measured data of transformer core loss with the figures calculated by edge-nodal coupled $E-\psi$ method, NFEM, EFEM and Steinmetz method, the comparison results show that: the edge-nodal coupled $E-\psi$ method has higher …


Stylization Rendering Algorithm Based On Interactive Graph Cuts Method For Image Segmentation, Zhao Yang, Guowu Yuan, Dangen Xie, Xu Dan Aug 2020

Stylization Rendering Algorithm Based On Interactive Graph Cuts Method For Image Segmentation, Zhao Yang, Guowu Yuan, Dangen Xie, Xu Dan

Journal of System Simulation

Abstract: The image is cut into two parts, the object and background, using the Graph Cuts interactive image segmentation algorithm. Through interactive image segmentation, user segmented image into a foreground region and a background region. For background area, a variety of non-photorealistic rendering algorithm was designed, which could render the original image into artistic images with other cartoon painting, pencil drawing or painting style. For foreground region, the algorithm maintained its feathers unchanged. By merging foreground and background areas, the artistic images were obtained with variety styles. Experiments show that the algorithm designed can get the desired result for processing …


Research On Scheduling Problem Of Single-Arm Cluster Tools With Residency Time Constraints, Lu Rui, Linying Li Aug 2020

Research On Scheduling Problem Of Single-Arm Cluster Tools With Residency Time Constraints, Lu Rui, Linying Li

Journal of System Simulation

Abstract: Considering the scheduling model and schedulibility for single-arm cluster tools with wafer residency time constraints, a mixed- integer linear programming model with both single-arm and temporal constraints for processing module was constructed. The rationality of equivalent processing time for concurrency module was theoretically proved. Based on this, the periodic wafer processing and transportation procedure for both single-arm and processing module was analyzed. Meanwhile, the schedulibility conditions for cluster tools were proved. The simulation experiments were carried out to test the model and schedulable conditions, and the results reveal the validity and feasibility of the presented model.


Low-Complexity Soft-Decision Decoding Algorithm For Bch Code In Beidou System, Guowei Qu, Songfeng Deng Aug 2020

Low-Complexity Soft-Decision Decoding Algorithm For Bch Code In Beidou System, Guowei Qu, Songfeng Deng

Journal of System Simulation

Abstract: A low-complexity soft-decision decoding algorithm based on the re-encoding technique was proposed for the BCH(15,11) code in BeiDou satellite navigation system. Several candidate information sequences were constructed by the soft-decision vector and then re-encoded in the algorithm if the error in the hard-decision result was detected. The correlation between each codeword and the soft-decision vector was calculated, and the codeword with the maximum correlation value was selected as decoding output. Simulation results show that the presented algorithm outperforms traditional hard-decision decoding at the expense of moderate complexity increase. Moreover, the storage of error-correction ROM signal is avoided. …


Multiresolution Scene Matching Algorithm For Infrared And Visible Images Based On Non-Subsampled Contourlet Transform, Liu Gang, Guangyu Wang, Zhou Heng, Mingjing Wang Aug 2020

Multiresolution Scene Matching Algorithm For Infrared And Visible Images Based On Non-Subsampled Contourlet Transform, Liu Gang, Guangyu Wang, Zhou Heng, Mingjing Wang

Journal of System Simulation

Abstract: Aiming at scene matching problem for taking infrared image as the actual data and the visible image as the referenced data, a multiresolution matching algorithm was proposed based on non-subsampled contourlet transform (NSCT). By using the transform of phase congruency transform, the difference of grayscale and contrast between infrared image and visible light image was weakened. Subsequently, the two types of images were separately transformed into non-subsampled contourlet domain and the proposed method took the Krawtchouk invariant moment as matching feature. The presented method, which used the improved genetic algorithm (GA) as searching strategy which conquered the precocious phenomenon, …


Study On Hand Gesture Recognition And Portfolio Optimization Model Based On Svm, Zhiwei Cai, Shuyan Wu, Junfeng Song Aug 2020

Study On Hand Gesture Recognition And Portfolio Optimization Model Based On Svm, Zhiwei Cai, Shuyan Wu, Junfeng Song

Journal of System Simulation

Abstract: Hand gesture recognition was researched. The idea of extracting related features was proposed by using SVM algorithm in machine learning domain, and combination optimization method was used, which consists of ANN, HMM and DTW, to do hand gesture recognition. The experimental results show that portfolio optimization model based gesture recognition method has high accuracy and is very effective.


Modeling And Motion Analysis Of Multi-Bodies Dynamic Of Unmaned Parafoil Vehicle, Zhang Hao, Zili Chen, Jingang Qiu Aug 2020

Modeling And Motion Analysis Of Multi-Bodies Dynamic Of Unmaned Parafoil Vehicle, Zhang Hao, Zili Chen, Jingang Qiu

Journal of System Simulation

Abstract: Unmanned Parafoil Vehicle (UPV) has gradually become a hotspot in the flexible wing vehicle research filed for its superior fight performance and advantages in application. An eight degrees of freedom (DOF) nonlinear dynamic model of UPV in mechanism law was proposed, aiming at the structure characteristics of the two flexible connections, and considering the added mass of canopy and the relative motion of two bodies. The response of model to different levels of thrust changes was simulated and analyzed, pulling a single steering line and pulling the left and right steering lines of canopy symmetrically on the steady state …


Simulation And Analysis Of Airborne Phase Array Weather Radar Reflectivity, Wang Lei, Chaopeng Yu, Liu Ping Aug 2020

Simulation And Analysis Of Airborne Phase Array Weather Radar Reflectivity, Wang Lei, Chaopeng Yu, Liu Ping

Journal of System Simulation

Abstract: The relation between radar parameters such as radar gain, beam width and impulse width and radar reflectivity based on the parameters of airborne phase array weather radar at X-band were proposed. Combined with weather radar equation correction and flight parameters, horizontal sector scanning and vertical sector scanning reflectivity data of airborne phased array weather radar were simulated based on new generation weather radar (CINRAD/SA) reflectivity. The results show that along the radial direction, the distance resolution of airborne phase array radar used impulse compress technology is higher than new generation weather radar and along the shear direction, because antenna …


Analysis And Simulation Of A Class Of Time-Varying Wireless Networked Control Systems, Weihua Deng, Minrui Fei Aug 2020

Analysis And Simulation Of A Class Of Time-Varying Wireless Networked Control Systems, Weihua Deng, Minrui Fei

Journal of System Simulation

Abstract: The problem of stabilization was investigated for a class of discrete time-varying systems over a physical IEEE 802.11b wireless channel. The wireless network-induced delays were characterized by an inverse Gaussian distribution model (IGDM) and the time-varying nature was depicted by uncertain parameter model. The model-based state feedback controller was designed to compensate the influence of delays and time-varying nature. And the stochastic stabilisability of discrete time-varying networked control system was analyzed and the solution of controller was given in the form of linear matrix inequalities (LMIs). The effectiveness of the proposed methods was illustrated by numerical simulation examples.


Robust Steerable Frequency Invariant Beamformer Design Based On Srv-Cls, Suting Chen, Zhang Wei Aug 2020

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 …


Dynamic Arrival Sequencing & Scheduling Based On Branch & Bound Algorithm, Junfeng Zhang, Wang Fei, Tengteng Ge Aug 2020

Dynamic Arrival Sequencing & Scheduling Based On Branch & Bound Algorithm, Junfeng Zhang, Wang Fei, Tengteng Ge

Journal of System Simulation

Abstract: Optimization of arrival sequencing and scheduling is not only the prerequisite for properly allocating and fully utilizing the runway resource, but also the fundamental element for improving terminal operation efficiency. Dynamic arrival sequencing was obtained by time-triggered sliding time window method. On the basis of accurate 4D trajectory prediction, branch and bound algorithm was adopted to generate an optimal sequence, combined with the actual operation constraints. Taking Shanghai Pudong Airport as an example for simulation, the optimization results were compared with the actual landing time and simulation results based on first come first serve strategy. The results indicate that …


Study Of Synchronization For Fractional-Order Hyperchaotic System And Its Application In Secure Communication, Xue Wei, Jinkang Xu, Hongyan Jia Aug 2020

Study Of Synchronization For Fractional-Order Hyperchaotic System And Its Application In Secure Communication, Xue Wei, Jinkang Xu, Hongyan Jia

Journal of System Simulation

Abstract: A unidirectionally coupled synchronization method was adopted to design and implement the synchronization for the reported commensurate fractional-order hyperchaotic system, and its correctness and effectiveness were analyzed in theory. Moreover, taking an example of 3.6-order hyperchaotic system, analog circuits were designed to implement the fractional-order hyperchaotic system and its unidirectionally coupled synchronization with the frequency-domain approximation method based on Bode diagram. By conducting the circuit implementation, it is found that the results of the circuit implementation are in good agreement with those of the numerical simulation, which demonstrates the feasibility of the synchronization. On this basis, a secure communication …


Simulation Study On External Explode Of Large Equivalent Charge On Large Buildings, Weiping Zhao, Xiankun Ge, Chuanwu Liu, Fengchun Zhu Aug 2020

Simulation Study On External Explode Of Large Equivalent Charge On Large Buildings, Weiping Zhao, Xiankun Ge, Chuanwu Liu, Fengchun Zhu

Journal of System Simulation

Abstract: The particle algorithm in AUTODYN, Smoothed Particle Hydrodynamics (SPH), was used to simulate dynamic damage of the external explosion on large buildings, which provided a visual effect. The dynamic damage details of reinforced concrete and brick masonry structure at different time were proposed by the simulation of single component. Additionally, the overpressure of shock wave, caving velocity and kinetic energy were obtained. It shows that the caving can speed up to a maximum value of 152 m/s with the kinetic energy of 18 000 J, that means a great damage to personnel and equipment in the building. Under …


Adaptive Minimum Entropy Blind Equalization Algorithm Based On Quantum Artificial Fish Swarm Optimization, Yecai Guo, Wu Xing, Huang Wei, Wang Hui Aug 2020

Adaptive Minimum Entropy Blind Equalization Algorithm Based On Quantum Artificial Fish Swarm Optimization, Yecai Guo, Wu Xing, Huang Wei, Wang Hui

Journal of System Simulation

Abstract: In order to improve the equalization performance of high order inconstant modulus signals, adaptive minimum entropy super-exponential iteration blind equalization algorithm based on quantum artificial fish swarm optimization was proposed. The proposed algorithm could accelerate convergence rate via super-exponential iteration algorithm and could further decease the mean square error of the super-exponential iteration adaptive minimum entropy blind equalization algorithm via using the global optimization of the quantum artificial fish swarm algorithm designed by Schrodinger equation. The simulation results demonstrate that the proposed algorithm has fast convergence rate and lower mean square error for different higher modulation signals comparison with …


Vehicle Routing Optimization Model Of Cold Chain Logistics Based On Stochastic Demand, Xiangguo Ma, Tongjuan Liu, Pingzhe Yang, Rongfen Jiang Aug 2020

Vehicle Routing Optimization Model Of Cold Chain Logistics Based On Stochastic Demand, Xiangguo Ma, Tongjuan Liu, Pingzhe Yang, Rongfen Jiang

Journal of System Simulation

Abstract: The costs of vehicle distribution in the process of cold chain logistics is analyzed and amended; A mathematical model with mixing time window is built to balance the customers' service request with importance level; To minimize the total cost, a mathematical model which uses a factor to make balance between the stability of customer demand fluctuation and the cost increase in the assignment phase is established. Based on MATLAB software, the optical solution is found with adaptive genetic algorithm by taking the background of a distribution center to simulate and analyze.


Repairable K/N Voting System Life Situation Model Analysis And Simulation From Time Response, Yongfeng Fang, Jianjun Chen Aug 2020

Repairable K/N Voting System Life Situation Model Analysis And Simulation From Time Response, Yongfeng Fang, Jianjun Chen

Journal of System Simulation

Abstract: For the k of k/n system is given according to the one's experience in the current, the probability of the failure of the singular system components was given according to the stress-strength interference theory and the load distribution of the component withstand. The dynamic reliability prediction model of the repairable k/n system was established by using probabilistic differential equations and by the repairable system components moving in reliable and failure. The equation was solved and their answers were shown to give the precisely k when the k would be determined. The model shows accuracy and feasibility …


Modeling And Simulation Of Executable Architecture Based On P-Devs, Jianpeng Hu, Linpeng Huang Aug 2020

Modeling And Simulation Of Executable Architecture Based On P-Devs, Jianpeng Hu, Linpeng Huang

Journal of System Simulation

Abstract: Executable architecture modeling plays a vital role in the design of complex systems and System of Systems (SoS), but there is still no common view and standard, unified execution mechanism and environment for an executable architecture. Three major elements of executable architecting were analyzed and summarized with a comparison among the options of these elements. To realize automated transformation from graphical models to executable codes, a generic modeling approach to executable architecture of SoS based on Parallel Discrete Event System Specification (P-DEVS) was proposed, and a case study of airport SoS shows its feasibility and effectiveness.


Research On Switched Current Mirror Mismatch And Simulation, Jierong Guo, Yigang He, Changqing Liu Aug 2020

Research On Switched Current Mirror Mismatch And Simulation, Jierong Guo, Yigang He, Changqing Liu

Journal of System Simulation

Abstract: Typical sources of switched current mirror mismatch were discussed. The most important three parameter of mismatch: transconductance, threshold voltage and the sub threshold slope were analyzed, due to the switch current circuit adopts the width to length ratio characteristic for calibration design. SPICE model using Hspice platform and 0.18 um BSIM3_V3.1 were proposed for circuit simulation. The simulation and analysis of mismatch were executed based on two kinds of operating rules of weak inversion and strong inversion. The compensation ability for mismatch was provided by floating gate switch current mirror which was also verified by simulation. Analysis and simulation …


Using Raster Lattices To Build Terrain Attribute Of Wargame Map, Jinming Zhang Aug 2020

Using Raster Lattices To Build Terrain Attribute Of Wargame Map, Jinming Zhang

Journal of System Simulation

Abstract: Wargame map is a sketchy description of geographical environment under certain conditions. It is used to assist commanders or operational models to locate spatial positions and to determine spatial attributes. The former process is called geometric modeling and the latter attribute modeling, and the combination of which is known as Wargame Map Modeling. A Raster Lattice Algorithm for attribute modeling was proposed, which could effectively reduce modeling complexity and improve modeling efficiency. The basic process of attribute modeling and discussing its difficulty was described, i.e., the calculation of the covered areal ratio between hexagon and the geographical environment element. …


Nonlinear H Control For Marine Speed With Parameter Perturbation And Ambient Interference, Yupeng Yuan, Zhang Meng, Xinping Yan, Guo Bo, Jianglong Wan Aug 2020

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 …