Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Simulation (135)
- Path planning (76)
- Genetic algorithm (48)
- Deep learning (44)
- Numerical simulation (44)
-
- Digital twin (42)
- Virtual reality (42)
- Modeling and simulation (39)
- Multi-objective optimization (39)
- Particle swarm optimization (35)
- Reinforcement learning (34)
- Modeling (33)
- Fault diagnosis (29)
- Attention mechanism (28)
- Deep reinforcement learning (28)
- UAV (26)
- Neural network (25)
- Simulation model (25)
- Complex network (22)
- System simulation (22)
- System dynamics (21)
- Visualization (21)
- Virtual simulation (20)
- DRL (19)
- Optimization (19)
- Multi-agent (18)
- Trajectory planning (18)
- Traffic simulation (17)
- Unity3D (17)
- A* algorithm (16)
- Publication Year
Articles 3451 - 3480 of 3880
Full-Text Articles in Systems Science
Trust Evaluation Model Based On Fuzzy Set And D-S Evidence Theory In Wireless Sensor Network, Zhiping Zhou, Xiaoxiao Zhao, Nannan Shao
Trust Evaluation Model Based On Fuzzy Set And D-S Evidence Theory In Wireless Sensor Network, Zhiping Zhou, Xiaoxiao Zhao, Nannan Shao
Journal of System Simulation
Abstract: A trust evaluation model based on fuzzy set and D-S evidence in wireless sensor network is proposed. Considering security requirements and energy consumption, three typical trust factors are defined to calculate node’s direct trust which is for fuzzy classification by using fuzzy set theory. Fuzzy membership function is the basic belief function of the D-S evidence theory. Indirect trust is obtained from neighbor nodes’ recommendations, the direct trust and indirect trust are fused according to Dempster combination rule after being amended with weight. The effective combination of identity-based cryptosystem and the trust management mechanism improve the security …
Forestry Felling & Cultivation Machine Virtual Training System Based On Unity3d, Bowen Cheng, Yili Zheng, Qingqing Huang, Jinhao Liu
Forestry Felling & Cultivation Machine Virtual Training System Based On Unity3d, Bowen Cheng, Yili Zheng, Qingqing Huang, Jinhao Liu
Journal of System Simulation
Abstract: A forestry felling & cultivation machine virtual training system based on Unity3D was developed. The models of forestry felling & cultivation machine were built up using 3dsMAX with the assistance of SolidWorks based on a forestry felling & cultivation machine. The models of forestry felling & cultivation machine and trees were imported into Unity3D to create a virtual operating environment. Each part of forestry felling & cultivation machine needs to be processed for the establishment of paternity in accordance with the simulation, the corresponding mathematical model was established to simulate the motion of the manipulator based on the analysis …
Elevator Traffic Pattern Recognition With Fcm Clustering Based Fuzzy Neural Network, Zhenshan Yang, Wenjiao Yue
Elevator Traffic Pattern Recognition With Fcm Clustering Based Fuzzy Neural Network, Zhenshan Yang, Wenjiao Yue
Journal of System Simulation
Abstract: Elevator traffic demand pattern recognition is the prerequisite for effectively implementing the strategies of elevator group control system. In view of the characteristics of time-varying, nonlinear and uncertainty of elevator traffic demand, an elevator traffic pattern recognition method with FCM (Fuzzy C-means) clustering based fuzzy neural network is presented. The method introduces the fuzzy logic into the calculation and learning of BP neural network, and employs FCM clustering algorithm to cluster the original traffic demand to realize the fuzzy partition of the input space of fuzzy system to determine the initial value of network membership function and clustering center …
Parallel Pattern Recognition Of Leak Current Data Using Spark-Knn, Li Li, Yongli Zhu, Yaqi Song
Parallel Pattern Recognition Of Leak Current Data Using Spark-Knn, Li Li, Yongli Zhu, Yaqi Song
Journal of System Simulation
Abstract: With the rapid development of smart grid, the status monitoring data of power grid equipment increase exponentially and gradually form the big data. Traditional computing architectures are no longer to meet the demand of computing performance. This paper explores how Spark and Cloud computing can accelerate performance of missive insulator leak current data pattern recognition. The Parallel KNN (k-Nearest Neighbor) algorithm is designed and implemented by using Spark and Aliyun E-MapReduce cloud computing platform. The results from experiments show that the performance of Spark-KNN is 2.97 times of MapReduce-KNN and gains acceleration of 8.8 times. The experimental results confirm …
Application Of Multiple-Stepwise And Kalman Filtering In Haze Forecast, Yunhao Xian, Hengde Zhang, Yonghua Xie, Le Yang
Application Of Multiple-Stepwise And Kalman Filtering In Haze Forecast, Yunhao Xian, Hengde Zhang, Yonghua Xie, Le Yang
Journal of System Simulation
Abstract: Considering the importance of objective haze forecast and the low accuracy rate of haze forecast, a new haze objective forecast correction method based on the multiple stepwise regression algorithms and the Kalman filtering algorithm is proposed. The multiple stepwise regression method is used to control the physical factor of the dependent variable, and the visibility forecast equation is established. The Kalman filtering method is adopted to correct the regression coefficient in multivariate stepwise regression algorithm according to the actual data, and the haze objective forecast correction model is established. The experiments are carried out in Beijing, Guangzhou, Nanjing and …
Optimal Operation Of Grid-Connected Microgrid Based On Abc Algorithm, Qiuli Cui
Optimal Operation Of Grid-Connected Microgrid Based On Abc Algorithm, Qiuli Cui
Journal of System Simulation
Abstract: An optimal scheduling model of grid-connected microgrid composed of wind power generators, photovoltaic cells, fuel cells and batteries is established. The economy and environmental protection elements are considered in this model. To maximize the role of peak shaving and valley filling in microgrid system, based on the time-of-use price mechanism, the heuristic rules combined with peak shaving and valley filling is used to design a grid-connected energy scheduling strategy. By monitoring the net load state and the price time interval, and adjusting the particular state of the micro source of power, the system optimal energy scheduling state is obtained. …
Stress Distribution Formula Of Threads Casing Joint Under Symmetrical Load, Tong Hua, Xiaohong Tang, Xiaohua Zhu, He Huan, Haoran Tao
Stress Distribution Formula Of Threads Casing Joint Under Symmetrical Load, Tong Hua, Xiaohong Tang, Xiaohua Zhu, He Huan, Haoran Tao
Journal of System Simulation
Abstract: While itis difficult tomeasure thestress distribution of casing threads underground without calculation by finite element method. Here assumes a deformation compatibility factor Ux, use an initial calculation to represent the thread stress, f(x)=f0Ux, and applythe ABAQUS finite element software to calculate the stress distribution of the threads under different symmetrical loads. Obtain the expressions of Ux by curve fitting, and get the threads stress calculation formula to provide an intuitive, fast and accurate method of calculation for the site. Providea theoretical reference for development and manufacture of casing …
Overview Of Multi-Agents Modeling And Simulation For Underwater Unmanned Combat Systems, Hongtao Liang, Fengju Kang, Yanfang Fu
Overview Of Multi-Agents Modeling And Simulation For Underwater Unmanned Combat Systems, Hongtao Liang, Fengju Kang, Yanfang Fu
Journal of System Simulation
Abstract: Military UUV is developing toward the direction of intellectualization and coordination of multi-UUV system. It is composed of complex underwater unmanned system (UUS) with changeable underwater environment and complex combat mission. Multi-agents (MAS) modeling technology has become the mainstream method to study this kind of complex system. The development and characteristics of UUS are briefly and comprehensively reviewed. The latest developments of MAS theory are systematically summarized, and MAS modeling and simulation technology for multi-UUV cooperative combat system (MUCCS) are analyzed. A novel MAS theory method, that is immune agent interactive network (IAIN), is proposed, which combines the modeling …
Neural Coding Model For Fast And Significant Perceptual In The Pigeon Optic Tectum, Songwei Wang, Shuman Huang, Shi Li, Mengke Wang
Neural Coding Model For Fast And Significant Perceptual In The Pigeon Optic Tectum, Songwei Wang, Shuman Huang, Shi Li, Mengke Wang
Journal of System Simulation
Abstract: In the classical target recognition theory, many neurons in the mammalian retina and LGN perform DoG operations. Their functions are generally considered to be whitening, eliminating redundancy, and enhancing edges. Where is the redundant information? In this paper, the electrophysiological study of the ON-OFF neurons of the dove optic roof was performed. It was found that the FSL was used to carry out the rough and fast transfer of the whole scene information, and then the salient features in the scene were successively transmitted using the issue rate. For this reason, by analyzing the response pattern of neurons, this …
Numerical Simulation Of Borehole Stability In Underbalanced Drilling Coal Seam, Yumei Li, Su Zhong, Zhang Tao, Delong Zhang, Liwei Yu, Si Na
Numerical Simulation Of Borehole Stability In Underbalanced Drilling Coal Seam, Yumei Li, Su Zhong, Zhang Tao, Delong Zhang, Liwei Yu, Si Na
Journal of System Simulation
Abstract: According to the formation parameters of No.3 coal seam in the Qinshui Basin, Shanxi Province, considering the interaction between seepage and deformation in the borehole wall of coal seam, using the finite element method for establishing the stable elastoplastic numerical model of the borehole in coal seam,the variation of pore pressure near the wellbore wall with the seepage time and the effect of time delay on wellbore stability under underbalanced drilling condition were studied. The variation law of maximum displacement and maximum plastic deformation around borehole wall with bottom pressure were analyzed. The simulation results show that there …
Permanent Magnet Synchronous Motor Multi-Parameter Identification Based On Improved Salp Swarm Algorithm, Mengqiu Wang, Wang Yan, Zhicheng Ji
Permanent Magnet Synchronous Motor Multi-Parameter Identification Based On Improved Salp Swarm Algorithm, Mengqiu Wang, Wang Yan, Zhicheng Ji
Journal of System Simulation
Abstract: Since the multi-parameter identification of permanent magnet synchronous motor (PMSM) has slow speed and low accuracy, a parameter identification method based on the improved salp swarm algorithm was proposed in this paper. The algorithm firstly adopted the self-adaptive evaluation-move strategy and neighborhood optimum guide strategy based Von Neumann topology to update the position of followers twice, which strengthened information cooperation in the population and accelerated the convergence rate of parameter identification. Secondly, the algorithm used the opposition-based learning strategy to perturb the population position with a certain mutation probability, that avoided local optimum and misconvergence of the parameters. The …
Analysis And Optimization Of Hospital Pharmacy Sorting System Based On Simulation, Liu Shuang, Lü Chao
Analysis And Optimization Of Hospital Pharmacy Sorting System Based On Simulation, Liu Shuang, Lü Chao
Journal of System Simulation
Abstract: The assignment rules are presented by researching system data information with a large Chinese medicine pharmacy sorting system as an object. Based on simulation technology, the system model is presented; the system operation time, cost, efficiency, and assigned laws and human resources configuration as well as many other factors affecting the performance of the system are analyzed. Based on the analysis of the original system, three optimization schemes are designed and compared. The simulation results show that, during the same simulation period, the reallocation of human resources can reduce the economic cost, but it has little improvement on …
Improvement Of Grey Target Algorithm And Its Application In Assessment Of Marine Gas Turbine, Tongqing Wang, Mei Shan, Xiaobo Li, Jiajie Liu
Improvement Of Grey Target Algorithm And Its Application In Assessment Of Marine Gas Turbine, Tongqing Wang, Mei Shan, Xiaobo Li, Jiajie Liu
Journal of System Simulation
Abstract: In the modern shipbuilding industry, gas turbines are increasingly becoming the main power supply devices for ships with their good overall performance. The assessment of their overall performance is very important in the development and introduction of gas turbines. By using the grey target theory, a comprehensive gas turbine performance evaluation model is constructed and the grey target method can easily deal with the evaluation problem which has the characteristics of "small amount of data, lean information, and uncertainty". By discussing the influence of distinguishing coefficient in the algorithm, a method for determining the value of the distinguishing coefficient …
Impact Of Attractiveness And Influence Of Information On Cascade Size Distribution, Dong Jian, Bin Chen, Liu Liang, Chuan Ai, Zhang Fang, Xiaogang Qiu
Impact Of Attractiveness And Influence Of Information On Cascade Size Distribution, Dong Jian, Bin Chen, Liu Liang, Chuan Ai, Zhang Fang, Xiaogang Qiu
Journal of System Simulation
Abstract: The distribution of the cascade size can capture the distribution of popularity of a social network. Numerous studies have shown that the cascade size distribution follows fat-tail distributions, including power-law distribution and bimodal distribution; The underlying characteristic of this highly skewed distribution lacks quantitative experimental analysis. Based on the heterogeneous stochastic information dissemination model, namely the SVRF model, this paper examines the impact of the information attractiveness and influence on the cascade size distribution through lots of computational experiments. We find that when the mean value of the information influence and attractiveness is small, the cascade sizes follow …
Simulation Analyzing For Drawing Up Methodology Of Cooperative Train Working Diagram And Route Allocation Plan, Zhou Yan
Journal of System Simulation
Abstract: The quality of the train diagram directly affects the efficiency of the transport operation and management. Though the inadequacies of computer drawing train working diagram were reviewed, an integrated drawing up methodology of train diagram and train route allocation plan was put forward to optimize the allocation of resources, based on the interaction relationship of train diagram and train route allocation plan. On that basis, the overall state transition adjustment algorithm, which consists of the “full timetable” result and collaborative model route allocation plan, was also proposed. Finally, the prototype system framework based on .NET was described, and the …
Three-Dimensional Model Of Magnetostrictive Force Sensor Considering Stress Coupling And Experimental Research, Li Bo, Jiabin Yang, Shu Liang, Penghui Li, Wu Hong
Three-Dimensional Model Of Magnetostrictive Force Sensor Considering Stress Coupling And Experimental Research, Li Bo, Jiabin Yang, Shu Liang, Penghui Li, Wu Hong
Journal of System Simulation
Abstract: Considering the brittleness of normal magnetostrictive and piezoelectric materials, a new magnetostrictive force sensor is proposed, in which Galfenol alloy is taken as the sensing element. Considering the anisotropy of Galfenol, three-dimensional magneto-mechanical coupled model is presented on the basis of electromagnetic and mechanical governing equation. The nonlinear magnetization behavior of Galfenol is described by employing the discrete energy-averaged model. The coupling of the magnetization model and the structural model is implemented with the PDE weak form equations. The model is solved by using the weak form module of Comsol Multiphysics. Simulation results show that both field and stress …
Design Of Fault Tolerant Control Visual Simulation System For Flying Wing Aircrafts, Shaojie Zhang, Qingkai Meng
Design Of Fault Tolerant Control Visual Simulation System For Flying Wing Aircrafts, Shaojie Zhang, Qingkai Meng
Journal of System Simulation
Abstract: A visual simulation platform based on Qt Quick was designed with respect to the simulation about fault tolerant control for flying wing aircrafts. Aircraft mathematical model and control law were developed using Simulink. Man-machine interface was developed based on Qt Quick to inject fault to Simulink model, load control law, setting up the simulation parameters and process, the interface can monitor and display graphically the key parameters to test and verify fault tolerant control laws. FlightGear visual engine was driven by MATLAB to achieve real-time visual flight simulation and the aircraft were showed in 3-D model. Baidu Map’s API …
Multi-Constraint Service Selection Based On Decomposition Of Global Qos, Fang Chen, Jindong Wang, Hengwei Zhang, Wang Na
Multi-Constraint Service Selection Based On Decomposition Of Global Qos, Fang Chen, Jindong Wang, Hengwei Zhang, Wang Na
Journal of System Simulation
Abstract: With the rapid growth of Web services in cloud computing environment, users make new demands on dynamic service composition, that quickly selects composite service which can meet multi-constraints. According to the demand, a multi-constraint service selection method based on decomposition of global QoS was proposed. A new cultural genetic algorithm was designed to decompose the global QoS constraints, and services were filtered by combining with the functional constraints between candidate services. An adaptive replacement strategy was used to dynamically adjust QoS constraint boundaries, so as to ensure the most appropriate composite service obtained by local selection. Experimental results show …
Research On Impact Performance Of Layer-Number Of 2024 Aerospace Aluminum Alloy Immobilized Target Against Bird Strike, Jianxin Xu, Jiajun Yuan, Yunfei Deng
Research On Impact Performance Of Layer-Number Of 2024 Aerospace Aluminum Alloy Immobilized Target Against Bird Strike, Jianxin Xu, Jiajun Yuan, Yunfei Deng
Journal of System Simulation
Abstract: In order to investigate the anti-penetration performance of target plate of the same thickness under different number of layers, a model of SPH(Smoothed Particle Hydrodynamics) cylindrical bird bullet to impact 2024 aerospace aluminum alloy Lagrange target is established by using the AUTODYN finite element software. The thickness of target is 1 mm, 2 mm, 3 mm and 4 mm, 1 mm and 2 mm target plate is divided into single and double, 3 mm target plate is divided into single, double and three layers, 4 mm target plate is divided into single, double and four layers. …
Fault Co-Simulation Of Fuel Regulator In A Certain Type Of Turbofan Engine, Wei Xiang, Benwei Li, Xinyi Yang, Xingbo Wang
Fault Co-Simulation Of Fuel Regulator In A Certain Type Of Turbofan Engine, Wei Xiang, Benwei Li, Xinyi Yang, Xingbo Wang
Journal of System Simulation
Abstract: A co-simulation method for fuel regulator fault diagnosis in a certain type of turbofan engine is performed, which consists of AMEsim Model of main fuel control system and Simulink Model of aero-engine. The AMEsim Model of main fuel system and Simulink Model of aero-engine are built and their accuracy is validated by experiments and the engine’s operating data, respectively. The co-simulation model based on the main fuel control system and the aero-engine is proposed through the interface of AMEsim and Simulink software. The typical faults and obviation methods are simulated by the co-simulation model. The research shows that the …
Study On Design And Simulation Of Pyramidal Horn Antenna, Denghua Li, Fangfang Ji, Hao Cui, Wenbai Chen
Study On Design And Simulation Of Pyramidal Horn Antenna, Denghua Li, Fangfang Ji, Hao Cui, Wenbai Chen
Journal of System Simulation
Abstract: In order to study the low-profile panel antenna that works in Ku band (12.25’12.75GHz), a high-gain Pyramidal horn antenna is designed as the unit of low-profile panel antenna. To meet dual polarization, it was taken into account that the radiation aperture of antenna unit has symmetric structure. Thus the feed waveguide is designed into a square waveguide. The proposed antenna is designed, simulated and optimized for antenna gain with HFSS (High Frequency Structure Simulator) software. Simulated results show that: in the Ku band, the reflection coefficient is less than -21dB; and the VSWR …
Assessment And Verification Of Code-Carrier Coherence On Bds, Dongxia Li, Fuhan Song, Ruihua Liu
Assessment And Verification Of Code-Carrier Coherence On Bds, Dongxia Li, Fuhan Song, Ruihua Liu
Journal of System Simulation
Abstract: In order to verify code-carrier coherence on BeiDou Navigation Satellite System (BDS), the monitoring and assessment system of code-carrier coherence on BDS is designed. Code-Carrier Divergence (CCD) monitor is designed to detect the anomaly status of ionosphere, and based on the detection results, ionosphere delay error is eliminated by using Divergence-Free Smoothing (DFree) or Ionosphere-Free Smoothing (IFree) separately. The values of integer ambiguity are calculated based on tri-frequency ambiguity decomposition model, and the cycle slip is detected by using tri-frequency pseudorange code and combination of carrier phase. Assessment and verification of code-carrier coherence can be conducted. It is …
Analysis And Optimization Of Mr Damper Based On Parallel Of Positive And Negative Stiffness, Yanbin Liu, Yawei Wang, Jianhai Han
Analysis And Optimization Of Mr Damper Based On Parallel Of Positive And Negative Stiffness, Yanbin Liu, Yawei Wang, Jianhai Han
Journal of System Simulation
Abstract: For purpose of reducing broadband vibration of precision machine tool from environment, a MR damper with squeeze mode was designed based on parallel of positive and negative stiffness. First, according to fluid continuity equation and momentum equation, the LPM (Lumped Parameter Model) was set up. Then, using two-way fluid-solid coupled nonlinear FEA (Finite Element Analysis), the flow field distribution was discussed for revealing flow characteristics of damper. Based on the LPM, the dynamic stiffness and displacement transfer rate, as well as the high-low frequency decoupling theory, were studied. Finally, multi-objective genetic algorithm was used to carry out the optimization …
Modeling And Simulating On Flow Characters Of Axial Piston Pump With Concial Cylinder Block Considering The Hydraulic Oil Containing Air, Donglin Tang, Wu Fan, Zhiquan Ma, Zhichun Zeng
Modeling And Simulating On Flow Characters Of Axial Piston Pump With Concial Cylinder Block Considering The Hydraulic Oil Containing Air, Donglin Tang, Wu Fan, Zhiquan Ma, Zhichun Zeng
Journal of System Simulation
Abstract: Aiming at the problem that air bubbles mix into hydraulic oil would affect fluid properties, and then would affect the flow characters of axial piston pump with concial cylinder block, according to the theoretical ananlysis, the generic submodel of the fluid properties and single piston/swash plate mechanism were developed by AMESet, and the simulation result verified the applicability of the fluid properties generic submodel. The model of whole pistion pump was developed by AMESim. The influences of air content in hydraulic oil and pistion dip angle on the flow characters of pistion pump were studied. The results …
High Performance Fault-Tolerant Scheduling Method And Simulation For Heterogeneous Multicore, Shigan Yu, Zhimin Tang, Xiaochun Ye, Zhimin Zhang
High Performance Fault-Tolerant Scheduling Method And Simulation For Heterogeneous Multicore, Shigan Yu, Zhimin Tang, Xiaochun Ye, Zhimin Zhang
Journal of System Simulation
Abstract: To deal with the problem of low performance and high power consumption when solving the transient fault of the processor with three mode redundancy (TMR), a task execution algorithm for heterogeneous multicore considering fault tolerant (TEAHFT) is proposed. The tasks to be executed are divided into sensitive tasks and fault-tolerant tasks. The sensitive tasks are executed in a TMR mode, and the fault-tolerant tasks are executed in a competitive scheduling mode. The task will be rerun in TMR method if the results of the fault-tolerant tasks do not meet the reliability threshold. The simulation experimental results show that TEAHFT …
Method And Simulation Of Gradual Rough Milling Based On Surface Deformation, Xiulin Sui, Xiaoqi Chen, Jianghua Ge
Method And Simulation Of Gradual Rough Milling Based On Surface Deformation, Xiulin Sui, Xiaoqi Chen, Jianghua Ge
Journal of System Simulation
Abstract: In view of uneven allowance and rough surface of traditional equal height stratification for rough milling, a gradual hierarchy process method was proposed. As the model established by T-spline surface has unified parameter domain, an improved variable distance offset method was used to define the rules of surface deformation, and a series of deformation surface sequences were obtained. The cutting depth, tool radius and other machining parameters were used as constraint conditions so as to get the sequence of processing layers. By planning the tool path of each layer, the whole tool path of gradual hierarchy process which was …
Cam Of Possible Accident For Longitudinal Slope Curve Of Mountain Freeway, Mingbao Pang, Zhanghui Cai
Cam Of Possible Accident For Longitudinal Slope Curve Of Mountain Freeway, Mingbao Pang, Zhanghui Cai
Journal of System Simulation
Abstract: Based on the analysis of vehicle driving behaviors and accidents, a cellular automaton (CA) simulation model of longitudinal slope curve on mountain freeway with the possible occurrence of traffic accident was established. The model was preliminarily validated via the comparisons between the accident rates in simulation experiments and that in actual statistics for the concrete roads. The possible schemes were determined by setting the different values of road geometric linear parameters. The nonlinear behaviors of traffic flow were simulated and the accident probabilities were obtained. The relations among the accident rate and the parameters’ values were discussed. …
Modeling And Simulation Of C2 System For Intercepting Lss Targets, Zhipeng Zhang, Su Zhong
Modeling And Simulation Of C2 System For Intercepting Lss Targets, Zhipeng Zhang, Su Zhong
Journal of System Simulation
Abstract: For analyzing the characteristics of low slow small (LSS) targets, a model of command and control (C2) system is established, the corresponding strategy is designed, and the designed scenario is simulated, which can improve the interception effect of the system on LSS targets. In the part of modeling, the trajectory of the target is plotted, the radar information is analyzed, the coordinate transformation between the parts is designed, and the track fusion is designed, which can improve discovery process. As the different characteristics of LSS targets, combined with the limited resources for intercepting weapons, the threat assessment strategies and …
Simulation Of Blade Tip Grooving Effect On Performance Of Twin-Stage Variable-Pitch Axial Fan, Xuemin Ye, Jiankun Zhang, Chunxi Li
Simulation Of Blade Tip Grooving Effect On Performance Of Twin-Stage Variable-Pitch Axial Fan, Xuemin Ye, Jiankun Zhang, Chunxi Li
Journal of System Simulation
Abstract: For a twin-stage variable-pitch axial fan, a novel blade tip treatment carving a chute from the pressure side to suction side is proposed, and fan performance under different blade tip treatments is simulated to determine the excellent treatment. The effects of blade tip grooving in a single stage or both stages on fan performance and internal dynamics are examined. Numerical results show that both blade tip treatments can improve the fan performance; the overall promotion of fan performance illustrates that the best scheme is the blade tip grooving in the first stage followed by the blade tip grooving …
Design Of Third-Order Zero-Free Mracs Taking State Variables From Model, Qian Chao, Song Fei
Design Of Third-Order Zero-Free Mracs Taking State Variables From Model, Qian Chao, Song Fei
Journal of System Simulation
Abstract: Since the current design method of the relative order n*≥3 MRACS taking state variables from model introduces some linear positive feedback loops, so it is difficult to be used in practical systems. This paper took the third-order zero-free (n*=3) system as the study object and designed the controller for third-order zero-free MRACS taking state variables from model by using the zero state equivalence relation between two different control systems. The design method of the controller is based on the Popov hyperstability theory. The controller only used integrators except for a differentiator and avoided introducing linear …