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“位置模糊”趋势下现代篮球运动中锋进攻技术特点分析 被引量:2
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作者 袁悦 《青少年体育》 2022年第5期74-77,共4页
本文运用文献资料法、逻辑分析法、数理分析法等研究方法,基于“位置模糊”概念,对传统中锋与“位置模糊”中锋的进攻特点及技术进行对比研究。结果表明,具有“位置模糊”特点的前锋、中锋的进攻方式及得分手段均优于传统中锋,但也有其... 本文运用文献资料法、逻辑分析法、数理分析法等研究方法,基于“位置模糊”概念,对传统中锋与“位置模糊”中锋的进攻特点及技术进行对比研究。结果表明,具有“位置模糊”特点的前锋、中锋的进攻方式及得分手段均优于传统中锋,但也有其进攻的局限性。建议:第一,在篮球训练中制订包含“位置模糊”的训练计划;第二,完善我国本土的篮球训练理论,以提高我国篮球整体竞技水平。 展开更多
关键词 “位置模糊” 篮球运动 中锋 进攻技术
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Criteria Selecting Knowledge Base in the FuzzyController of the Electrohydraulic Position Control System
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作者 高建臣 吴平东 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期84-91,共8页
Aim To analyse the influence of knowledge base on the performance of the fuzzy controller of the electrohydraulic position control system,and to determine their selection cri- teria. Methods Experiments based on diffe... Aim To analyse the influence of knowledge base on the performance of the fuzzy controller of the electrohydraulic position control system,and to determine their selection cri- teria. Methods Experiments based on different membership functions,scaling factors and con-trol rules were done separately.The experiment results and the influence of different know- ledge base on the control performance were analysed in theory so that criteria of selcting knowledge base can be summarized correctly.Results Knowledge base,including membershipfunctions, scaling factors and control rules,has a crucial effect on the fuzzy control system.Suitably selected knowledge base can lead to good control performance of fuzzy control sys-tem. Conclusion Being symmetric,having an intersection ratio of 1 and satisfying width con- dition are three necessities for selecting membership functions.Selecting scaling factors dependson both the system requirement and a comprehensive analysis in the overshoot,oscillation, rising time and stability. Integrity and continuity must be guaranteed when determining control rules. 展开更多
关键词 fuzzy control knowledge base position control systems fuzzy sets
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Improvement of Dynamic and Steady Characteristics of Pneumatic Position Servo with Fuzzy-PI Control
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作者 杨功军 赵彤 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期57+53-57,共6页
This paper provided a fuzzy-PI control. It makes use of the advantages of fuzzy controller for dynamic characteristics, and the advantages of PI control for steady characteristics of pneumatic position servo. Experime... This paper provided a fuzzy-PI control. It makes use of the advantages of fuzzy controller for dynamic characteristics, and the advantages of PI control for steady characteristics of pneumatic position servo. Experimental results show that positioning accuracy meets the conventional industrial needs, and prove that the fuzzy-PI controller to be correct and more effective than the usual PID controller. The control method improve the dynamic and steady characteristics of the system. 展开更多
关键词 non-linear control system fuzzy control/pneumatic position servo fuzzy-PI control
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Interval Type-2 fuzzy position control of electro-hydraulic actuated robotic excavator 被引量:3
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作者 Hassan Mohammed Yousif Kothapalli Ganesh 《International Journal of Mining Science and Technology》 SCIE EI 2012年第3期437-445,共9页
This paper deals with fuzzy intelligent position control of electro-hydraulic activated robotic excavator for the control of boom, arm and bucket axes. Intelligent control systems are required to overcome unde- sirabl... This paper deals with fuzzy intelligent position control of electro-hydraulic activated robotic excavator for the control of boom, arm and bucket axes. Intelligent control systems are required to overcome unde- sirable stick-slip motion, limit cycles and oscillations. Models of electro-hydraulic servo controlled front end loader excavators are highly nonlinear. The nonlinear model accounts for fluid flow rate of valve, pump hydraulics, and friction forces. The friction forces are modelled by Coulomb, viscous and Stribeck function. Interval Type-2 Fuzzy Logic Controller (IT2FLC) is used to study the time-domain position responses of axes in the presence of external applied load. It has the ability to control the position of each of the three axes with minimum actuator position errors. Models presented are accurate and study the dynamics of the actuator and load. To improve the transient behaviour of the robotic excavator, we elim- inated iitter of the bucket movement in the presence of nonlinearities. 展开更多
关键词 ExcavatorFuzzy controlMiningRobotType-2
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Decryption of pure-position permutation algorithms 被引量:3
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作者 赵晓宇 陈刚 +2 位作者 张亶 王肖虹 董光昌 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期803-809,共7页
Pure position permutation image encryption algorithms, commonly used as image encryption investigated in this work are unfortunately frail under known-text attack. In view of the weakness of pure position permutation ... Pure position permutation image encryption algorithms, commonly used as image encryption investigated in this work are unfortunately frail under known-text attack. In view of the weakness of pure position permutation algorithm,we put forward an effective decryption algorithm for all pure-position permutation algorithms. First, a summary of the pure position permutation image encryption algorithms is given by introducing the concept of ergodic matrices. Then, by using probability theory and algebraic principles, the decryption probability of pure-position permutation algorithms is verified theoretically; and then, by defining the operation system of fuzzy ergodic matrices, we improve a specific decryption al-gorithm. Finally, some simulation results are shown. 展开更多
关键词 DECRYPTION Image encryption FUZZY Position permutation
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Power loss reduction of distribution systems using BFO based optimal reconfiguration along with DG and shunt capacitor placement simultaneously in fuzzy framework 被引量:1
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作者 M.Mohammadi A.Mohammadi Rozbahani S.Bahmanyar 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期90-103,共14页
In distribution systems,network reconfiguration and capacitor placement are commonly used to diminish power losses and keep voltage profiles within acceptable limits.Moreover,the problem of DG allocation and sizing is... In distribution systems,network reconfiguration and capacitor placement are commonly used to diminish power losses and keep voltage profiles within acceptable limits.Moreover,the problem of DG allocation and sizing is great important.In this work,a combination of a fuzzy multi-objective approach and bacterial foraging optimization(BFO) as a meta-heuristic algorithm is used to solve the simultaneous reconfiguration and optimal sizing of DGs and shunt capacitors in a distribution system.Each objective is transferred into fuzzy domain using its membership function.Then,the overall fuzzy satisfaction function is formed and considered a fitness function inasmuch as the value of this function has to be maximized to gain the optimal solution.The numerical results show that the presented algorithm improves the performance much more than other meta-heuristic algorithms.Simulation results found that simultaneous reconfiguration with DG and shunt capacitors allocation(case 5) has 77.41%,42.15%,and 56.14%improvements in power loss reduction,load balancing,and voltage profile indices,respectively in 33-bus test system.This result found 87.27%,35.82%,and 54.34%improvements of mentioned indices respectively for 69-bus system. 展开更多
关键词 network reconfiguration distributed generation (DG) capacitor banks fuzzy framework bacterial foragingoptimization
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Modeling and fuzzy adaptive proportion-integration-differentiation control of X-Y position servo system actuated by oscillating pneumatic cylinder
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作者 袁德虎 Zhang Ziqun Meng Guoxiang 《High Technology Letters》 EI CAS 2010年第4期337-344,共8页
The servo system actuated by oscillating pneumatic cylinder for X-Y plate is a multi-variable nonlinear control system. Its mathematical model is established, and nonlinear factors are analyzed. Due to the existence o... The servo system actuated by oscillating pneumatic cylinder for X-Y plate is a multi-variable nonlinear control system. Its mathematical model is established, and nonlinear factors are analyzed. Due to the existence of deadlock zone and the small damp of the pneumatic oscillating cylinder, it is likely to result in overshoot, and there is also certain steady-state error, so online modifying of proportion-integration-differentiation (PID) parameters is needed so as to achieve better control performance. Meanwhile considering the stability demand for long-term run, a fuzzy adaptive PID controller is designed. The result of hardware-inloop (HIL) test and real-time control experiment shows that the adaptive PID controller has desirable serfadaptability and robustness to external disturbance and to change of system parameters, and its control per- fonnance is better than that of traditional PID controllers. 展开更多
关键词 fuzzy adaptive control servo system actuated by oscillating cylinder hardware-in-loop (HIL) trajectory tracking
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Research on Clothing Retail Store Location in Shanghai Business Streets With Fuzzy Comprehensive Evaluation Method
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作者 仓平 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期94-99,共6页
Based on the factors influencing location selection, this paper set up an evaluation system and got evaluation results of the related indexes in four main business centers in Shanghai with fuzzy comprehensive evaluati... Based on the factors influencing location selection, this paper set up an evaluation system and got evaluation results of the related indexes in four main business centers in Shanghai with fuzzy comprehensive evaluation method. In the mean time, this method can be applied in the evaluation of retail store location selection. 展开更多
关键词 Fuzzy Comprehensive Evaluation Method LOCATION Downtown
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Dynamic Friction Control Using Dynamic Structured RFNN and Friction Parameter Estimator
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作者 Seong-ik HAN Kwon-soon LEE +2 位作者 Dae-yeon YEO Sang-ok HAN Kyung-wan KOO 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期191-194,共4页
A nonlinear dynamic friction control is dealt with using dynamic friction observer and intelligent cantrol. The adaptive dynamic friction obsrver based on the LuGre friction is proposed to estimate the friction parame... A nonlinear dynamic friction control is dealt with using dynamic friction observer and intelligent cantrol. The adaptive dynamic friction obsrver based on the LuGre friction is proposed to estimate the friction parameters and a directly friction state variable The dynamic structured Fuzzy Neural Network (RFNN) is designed to give additional robustness to the cantrol system under the presence of the friction model uncertainty. A proposed composite cantrol scheme is applied to the position tracking control of the servo systen. The performances of the proposed friction observer and the friction controller are demonstrated by simulation. 展开更多
关键词 LuGre friction model adaptive friction observer dynamic structured RFNN servo system control
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