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1.
The majority difficulty for uncertainty system control is that agreements haven't been arrived in concept of uncertainty information and its characteristics, uncertainty system and its properties. Therefore some control problems have discussed based on some confused concepts, and the result shows that the study on uncertainty system control hasn't made great progress yet. In addition, problems concerning uncertainty system control are very wide in the practical engineering. Aimed at above problems the concept of uncertainty information and its classification, basic properties of uncertainty system and desired control strategy based on own practical experience are studied. Finally, that intelligent control strategy is wise choice for uncertainty system control based on successful engineering application.  相似文献   

2.
Because there are lots of difficulties in mathematic modeling for uncertainty complex object, so it is not suitable to utilize traditional methods in some aspect such as identification, analysis, synthetical design and implementation. Especially, for the idea of system modeling, it is very different in comparison with traditional mathematic modeling, therefore, it is very difficult to study control problem for uncertainty system in technology and theory. On the basis of summarizing characteristics of uncertainty complex object, present to establish generalized control model, and apply intelligent control strategy to implement control effectively. In addition, authors also studied control algorithm and system structure. Engineering practice shows that it is effective and successful to establish generalized control model, and select intelligent control strategy for uncertainty control system.  相似文献   

3.
In view of the vehicle cornering or path changing under ultimate handling maneuver, a 3-DOF nonlinear vehicle dynamics model which takes the vehicle lateral velocity, yaw rate and body roll angle as the State variables is presented. Based on the dynamic analysis, the method which using additional yaw moment produced by different longitudinal braking force among each wheels to improving vehicle handling stability in emergency situations is discussed. Considering the sideslip angle as one of the vehicle state variables is difficult to measuring, the sideslip angle estimation based on vehicle dynamic model and kinematics is designed. And then, based on the theory of siding model control, the combining sliding model control system is founded, which taking the vehicle yaw rate and body side-slip angle errors between the estimated and the real as the input variables, and taking the braking torque and the steering angle as control aims. The simulation results indicate that the control method can effectively improve the vehicle lateral handling stability.  相似文献   

4.
In practical industrial fields, it is very difficult to control uncertain complexity object effectively, because there are various uncertainties from internal dynamic characteristic and external, surroundings disturbance for controlled object. Its complexity is not only shown in structure, but also in information relation, so it is uneasy to implement it on technology. Aimed at selecting puzzle of control strategy for uncertain complexity system control, the authors describe cybernetics model based on analysis on some kinds of control strategy and contrastive research, and the model is applied in physical engineering system successfully. Finally, the authors point out that intelligent control strategy should be selected for uncertain complexity system control, and that Human Simulation Intelligent Control is a wise choice.  相似文献   

5.
In this paper,the conception of bus voltage stability control area of local powersystem is presented,based on the practical criterion for voltage stability calculated by the real-timeinformation and the quasi-real time information form the power system.The method is test6d onIEEE-30-bus test system and results are satisfactory.  相似文献   

6.
Analysis and Control on Roof Stability of Rock-salt Cavity   总被引:1,自引:0,他引:1  
Analysis and control on roof stability of rock-salt cavity are very important to ensure safety and benefit in production, build and use of repertorv of rock salt cavity. Dynamic balance process and instability process of rock-salt carity roof are studied, and instability mechanism of rock-salt cavity roof is studied with catastrophe theory, and the influencing factor are analyzed, which will be theoretical basis of rock-salt cavity stability control.  相似文献   

7.
The issue of exponential stability for TS-model-based fuzzy chaotic control systems with constant or time-varying delays is investigated. A linear-feedback fuzzy controller is designed using parallel dispersal compensation technique for a large class of chaotic control systems. By means of the Lyapunov-Krasovskii functional approach in combination of the linear matrix inequality and differential inequality techniques, the criteria for exponential stability of the TS-model-based fuzzy controller are derived, and the corresponding control laws are presented. The results are easy to be calculated numerically because of the linear matrix inequalities representation.  相似文献   

8.
基于CiteSpace的外生菌根知识图谱计量分析   总被引:1,自引:1,他引:0  
为更好地了解和掌握外生菌根的国内研究进展,以"外生菌根"为主题词,时间跨度为1979—2018年,从CNKI数据库中得到相关文献1607篇,运用CiteSpace知识图谱分析工具对关键词、作者、机构进行可视化分析,并对外生菌根的研究进展、发展趋势和资助基金等方面进行相关分析。结果表明:(1)外生菌根研究经历了起步阶段、快速增长阶段和稳定发展阶段3个阶段;(2)1979年以来,外生菌根研究主要围绕外生菌根、外生菌根真菌、樟子松、马尾松、菌根真菌、油松、大型真菌、多样性等展开;(3)内蒙古农业大学林学院、抚顺矿业集团林业处、西北农林科技大学林学院是最主要的研究机构;(4)闫伟是外生菌根研究领域发文量最多学者;(5)《内蒙古农业大学学报》是外生菌根相关研究刊载论文数量最多的期刊;(6)国家自然科学基金是研究外生菌根投入最多的基金项目。随着国内学者的研究逐渐深入,国内外生菌根的研究取得了快速发展,相关研究逐渐深入,可以预见国内外生菌根的研究会取得非常可喜的成果。  相似文献   

9.
基于知识模型和GIS的棉花生产潜力评价系统   总被引:11,自引:2,他引:9  
引入知识模型概念,建立以棉花生产潜力知识模型为特征的知识系统,将知识工程和数据库有机结合,以 Mapinfo 5.5 为系统开发平台,利用 MapBasic和 Visual Basic程序设计语言,建立基于知识模型的棉花生产潜力评价系统,实现棉花生产潜力评价的计算机辅助决策。应用本系统对江苏地区棉花生产潜力进行实例评价,并与实际单产相比较,进行单产潜力、潜力系数和总产潜力的对比分析,确定棉花生产地域优势。  相似文献   

10.
基于知识模型的棉花管理决策支持系统   总被引:3,自引:1,他引:2  
张怀志  朱艳  曹卫星 《棉花学报》2005,17(4):201-206
通过对棉花栽培研究资料和专家知识的总结归纳,运用系统学方法和结构化途径,建立了基于知识模型的棉花管理决策支持系统(KMDSSCM)。它由数据库、知识模型库、专家咨询库和人机界面等部分组成;可以实现栽培方案设计、适宜生育指标确定、适时苗情调控、专家知识咨询和系统维护等功能,具有普适性强,独立性好等特点。实例分析结果表明,系统可以根据决策点的基础农情条件,设计出适宜的综合性栽培管理方案和生育指标动态。  相似文献   

11.
Based on the second method of Lyapunov stability theory, the stability of non-equilibrium state for multiphase system is analysed. The results show that the dV/dt is always less than zero ff the V-function, which is defined as the entropy generation of the system, is greater than zero for the non-equilibrium state in linear zone, and the system is absolutely stable. On the other hand, the stability of the system in non-linear zone is determined with the symbol of dV/dt.  相似文献   

12.
设计了一套水暖锅炉自动调温系统应用于农业生产,主要部件包括主机、辅机、控制系统和水暖管道装置等。基于PLC的锅炉补水泵控制系统能够对整个锅炉的运行状况进行监测、报警、控制,保证锅炉正常、可靠地运行。该设计克服了以往养殖水暖锅炉中存在的缺陷,可以保证锅炉补水泵控制系统稳定可靠工作。  相似文献   

13.
客观分析国内氮沉降研究现状,总结现阶段研究的重点与薄弱点,旨在为氮沉降的科研工作者与决策者提供数据参考.以"氮沉降"为主题词,从CNKI数据库中得到2009-2019年发表的相关文献754篇,运用CiteSpace知识图谱分析工具对关键词、作者、机构进行可视化分析,并对氮沉降的研究进展、发展趋势和资助基金等方面进行相关...  相似文献   

14.
The two-level handstand pendulum system based on fuzzy control is designed. It is impossible to adopt classical control theory, for the mathematical modeling of the system is nonlinear, the fuzzy control is proposed to improve the former linear control algorithms. For the key to fuzzy control is control rule, it becomes most important to design suitable fuzzy rules. Two methods, one based on experience and the other based on system simulation, are presented to set u Pan effective rule base. The practice proves that the control result is of well stability. A control example for two-level handstand pendulum system shows that the control law is efficient and more robust than the classical state feedback optimal control law with respect to errors produced by the external disturbances.  相似文献   

15.
基于本体的茶叶知识服务系统研究与实现   总被引:1,自引:1,他引:0  
传统农业知识服务系统缺乏语义支持,并且在农业领域应用极为不足,本研究提出利用本体论和语义网知识建立知识服务系统的必要性。以茶叶领域为例,分析了生产过程中各类用户的实际需要,设计了适合农业生产实际的茶叶知识服务系统工作流程与主要模块,模块由三层架构组成:用户服务接口,知识服务平台以及知识库。描述了系统实现中的关键技术,如茶叶本体的构建方法,系统信息抽取算法以及系统的具体实现等,初步实现了系统功能。  相似文献   

16.
基于温湿度指数的牛舍喷淋降温系统的控制   总被引:4,自引:2,他引:2  
针对夏季高温对奶牛的不利影响,本文对适合应用于牛舍的喷淋降温系统的控制部分进行了研究。根据奶牛的生理特性,该控制系统以温湿指数(THI)为主控参数,结合时间控制参数等,编制的定时控制喷淋降温模式,能使奶牛生活环境得到更为合理的控制,能更加有效的减轻奶牛热应激。本文对该控制系统软硬件设计的主要内容进行了阐述。该控制系统主要采用单片机技术来完成对喷淋降温设备的控制,其研究主要包括单片机控制单元和动力驱动单元的设计。单片机控制单元以AT89S52单片机为核心,通过设计的外围电路及编写的功能程序实现对动力驱动单元的控制;动力驱动单元通过线路的设计布置,实现喷淋模式中降温设备的交替运行功能,从而对喷淋降温设备进行直接控制。  相似文献   

17.
为了加快农业生产信息化和数字化的发展,节约宝贵的水资源,降低能耗,提高灌溉的质量和效率,提升控制管理水平,笔者以维控LEVI102A型触摸屏为人机界面,台达DVP60ES2型可编程控制器为控制核心构建了一套自动灌溉控制系统。该系统不仅可以根据当前土壤中含水率和用户设定的土壤含水率的情况自动控制水泵电机和电磁阀的启闭,遇到雨天自动停止灌溉,还可以按照用户设定的时间自动进行灌溉。该系统实现了灌溉的自动监控功能,节省了人力,节约了用水,提高了灌溉的质量和效率,具有造价低廉,运行稳定,操作便捷,维护简易,人机界面友好等优点,具有广阔的应用前景和实际使用价值。  相似文献   

18.
This article takes SOFC-PEM hybrid systems as the research object and considers the operating parameters to be uncertainty. Uncertainty analysis method based on Latin hypercube sampling involves quantifying the uncertainty in the input parameters in the form of appropriate distribution functions, propagating the uncertainty through a deterministic model to construct the output variability distributions, and analyzing the effects of operational parameter uncertainty on system output. Furthermore, non-traditional sensitivity analysis approach is used to evaluate the relative importance of various parameters considering this distribution structure. Results show that higher operating temperature of SOFC stack, lower fuel rate and lower fuel utilization of SOFC stack can reduce the influence of uncertainty on system output at the expense of system output. Uncertainty analysis can provides more credible basis for the optimization of design parameters under uncertainty.  相似文献   

19.
Aiming at systems which are of characteristics of multi-input and multi-output, nonlinearity and time-variation in the industrial control fields, this paper presents a intelligent PID control method based on ameliorative RBF neural networks, which constructs RBF neural networks identifier on-line and identifies a controlled object on-line by means of adopting the nearest neighbor-clustering algorithm, and adjusts parameters of PID controller on-line and realizes decoupiing control of multivariable, nonlinear and time-variation system. The simulation result indicates that the controller can get parameters which are optimal under some control law, it makes the decoupled system, compared to the PID control method based on the conventional RBF neural networks, has perfect dynamic and static performances, possesses the advantages of high precision, quick response speed and is of great adaptability and robustness.  相似文献   

20.
By comparing the techniges of the production and the logic predicate for knowledge representation, this paper presents a kind of constructure of combinatorial knowledge base applied to the expert system for switch operation in electric power system . This constructure of knowledge base to be expanded and revised easily,and it is cinvenitnt to build the general shell of the expert system.  相似文献   

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