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Construction of Control Lyapunov Functions for a Class of Nonlinear Systems 被引量:5
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作者 CAI Xiu-Shan HAN Zheng-Zhi WANG Xiao-Dong 《自动化学报》 EI CSCD 北大核心 2006年第5期796-799,共4页
The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematica... The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematically via Lyapunov equation. Moreover, by a control Lyapunov function of the feedback linearizable part and a Lyapunov function of the zero dynamics, a control Lyapunov function for the overall nonlinear system is established. 展开更多
关键词 Nonlinear systems control Lyapunov functions semiglobal stabilization zero dynamics.
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Design of Luenberger function observer with disturbance decoupling for matrix second-order linear systems-a parametric approach 被引量:1
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作者 Wu Yunli Duan Guangren 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期156-162,共7页
A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure ass... A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure assignment. By introducing the H2 norm of the transfer function from disturbance to estimation error, sufficient and necessary conditions for disturbance decoupling in matrix second-order linear systems are established and are arranged into constraints on the design parameters via Luenberger function observers in terms of the closed-loop eigenvalues and the group of design parameters provided by the eigenstructure assignment approach. Therefore, the disturbance decoupling problem is converted into an eigenstructure assignment problem with extra parameter constraints. A simple example is investigated to show the effect and simplicity of the approach. 展开更多
关键词 matrix second-order linear systems Luenberger function observers eigenstructure assignment disturbance decoupling
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Shape control on probability density function in stochastic systems 被引量:4
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作者 Lingzhi Wang Fucai Qian Jun Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期144-149,共6页
A novel strategy of probability density function (PDF) shape control is proposed in stochastic systems. The control er is designed whose parameters are optimal y obtained through the improved particle swarm optimiza... A novel strategy of probability density function (PDF) shape control is proposed in stochastic systems. The control er is designed whose parameters are optimal y obtained through the improved particle swarm optimization algorithm. The parameters of the control er are viewed as the space position of a particle in particle swarm optimization algorithm and updated continual y until the control er makes the PDF of the state variable as close as possible to the expected PDF. The proposed PDF shape control technique is compared with the equivalent linearization technique through simulation experiments. The results show the superiority and the effectiveness of the proposed method. The control er is excellent in making the state PDF fol ow the expected PDF and has the very smal error between the state PDF and the expected PDF, solving the control problem of the PDF shape in stochastic systems effectively. 展开更多
关键词 stochastic systems probability density function (PDF) shape control improved particle swarm optimization.
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Stabilization of discrete nonlinear systems based on control Lyapunov functions 被引量:1
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作者 Cai Xiushan Wang Xiaodong Lü Ganyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期131-133,共3页
The stabilization of discrete nonlinear systems is studied. Based on control Lyapunov functions, a sufficient and necessary condition for a quadratic function to be a control Lyapunov function is given. From this cond... The stabilization of discrete nonlinear systems is studied. Based on control Lyapunov functions, a sufficient and necessary condition for a quadratic function to be a control Lyapunov function is given. From this condition, a continuous state feedback law is constructed explicitly. It can globally asymptotically stabilize the equilibrium of the closed-loop system. A simulation example shows the effectiveness of the proposed method. 展开更多
关键词 control Lyapunov functions discrete systems STABILIZATION
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Universal construction of control Lyapunov functions for a class of nonlinear systems 被引量:1
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作者 Cai Xiushan Wang Xiaodong Zhang Haoran 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期598-602,共5页
A method is developed by which control Lyapunov functions of a class of nonlinear systems can be constructed systematically. Based on the control Lyapunov function, a feedback control is obtained to stabilize the clos... A method is developed by which control Lyapunov functions of a class of nonlinear systems can be constructed systematically. Based on the control Lyapunov function, a feedback control is obtained to stabilize the closed-loop system. In addition, this method is applied to stabilize the Benchmark system. A simulation shows the effectiveness of the method. 展开更多
关键词 control Lyapunov functions nonlinear systems stabilization.
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基于自由曲面和L-system的红掌生长模型
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作者 邹一波 褚诗贤 +1 位作者 葛艳 陈明 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期85-90,共6页
针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于... 针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于红掌生长规律的微分L-system,可有效模拟红掌的拓扑结构和生长过程;通过虚拟器官表示红掌器官的几何属性,降低微分L-system的复杂度。试验验证提出的方法对红掌各项生长指标拟合度可达0.89以上,并可对每个生长阶段的红掌进行模拟,能有效地对红掌的生长过程进行建模。 展开更多
关键词 红掌 自由曲面建模 L-system 生长函数 虚拟器官
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Random testing for system-level functional verification of system-on-chip 被引量:4
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作者 Ma Qinsheng Cao Yang +1 位作者 Yang Jun Wang Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1378-1383,共6页
In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity o... In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity of this method is proven theoretically.Specifically, testcases are generated according to many approaches of randomization.Moreover, the testbench for the system-level verification according to the proposed method is designed by using advanced modeling language.Therefore, under the circumstances that the testbench generates testcases quickly, the hardware/software co-simulation and co-verification can be implemented and the hardware/software partitioning planning can be evaluated easily.The comparison method is put to use in the evaluation approach of the testing validity.The evaluation result indicates that the efficiency of the partition testing is better than that of the random testing only when one or more subdomains are covered over with the area of errors, although the efficiency of the random testing is generally better than that of the partition testing.The experimental result indicates that this method has a good performance in the functional coverage and the cost of testing and can discover the functional errors as soon as possible. 展开更多
关键词 VLSI circuit VERIFICATION random process function TESTING system-ON-CHIP system-level.
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Stability Analysis of T-S Fuzzy Control Systems Based on Parameter-dependent Lyapunov Function 被引量:2
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作者 DINGBao-Cang SUNHe-Xu QIAOYu-E 《自动化学报》 EI CSCD 北大核心 2005年第4期651-654,共4页
For discrete-time T-S fuzzy systems, the stability and controller design method are in-vestigated based on parameter-dependent Lyapunov function (PDLF). T-S fuzzy systems di?er fromnon-fuzzy systems with polytopic des... For discrete-time T-S fuzzy systems, the stability and controller design method are in-vestigated based on parameter-dependent Lyapunov function (PDLF). T-S fuzzy systems di?er fromnon-fuzzy systems with polytopic description or multi-model description in that the weighting coef-ficients have respective meanings. They, however, have stability aspect in common. By adopting astability condition for polytopic systems obtained via PDLF, and combining the properties of T-Sfuzzy systems, new results are given in this paper. An example shows that by applying the newresults, the stability conditions that can be distinguished are less conservative. 展开更多
关键词 稳定性分析 模糊控制 参数设置 LYAPUNOV函数
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Functionality evaluation of system of systems architecture based on extended influence diagrams 被引量:1
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作者 ZHANG Mengmeng CHEN Honghui +2 位作者 ZHANG Xiaoxue LUO Aimin LIU Junxian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期510-518,共9页
System of systems architecture(SoSA) has received increasing emphasis by scholars since Zachman ignited its flame in 1987. Given its complexity and abstractness, it is critical to validate and evaluate SoSA to ensur... System of systems architecture(SoSA) has received increasing emphasis by scholars since Zachman ignited its flame in 1987. Given its complexity and abstractness, it is critical to validate and evaluate SoSA to ensure requirements have been met.Multiple qualities are discussed in the literature of SoSA evaluation, while research on functionality is scarce. In order to assess SoSA functionality, an extended influence diagram(EID) is developed in this paper. Meanwhile, a simulation method is proposed to elicit the conditional probabilities in EID through designing and executing SoSA. An illustrative anti-missile architecture case is introduced for EID development, architecture design, and simulation. 展开更多
关键词 system of systems architecture(SoSA) functionality evaluation extended influence diagram(EID) anti-missile architecture SIMULATION
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Direct adaptive control for nonlinear uncertain system based on control Lyapunov function method 被引量:1
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作者 Chen Yimei Han Zhengzhi Tang Houjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期619-623,共5页
The problem of adaptive stabilization of a class of multi-input nonlinear systems with unknown parameters both in the state vector-field and the input vector-field has been considered. By employing the control Lyapuno... The problem of adaptive stabilization of a class of multi-input nonlinear systems with unknown parameters both in the state vector-field and the input vector-field has been considered. By employing the control Lyapunov function method, a direct adaptive controller is designed to complete the global adaptive stability of the uncertain system. At the same time, the controller is also verified to possess the optimality. Example and simulations are provided to illustrate the effectiveness of the proposed method. 展开更多
关键词 adaptive control control Lyapunov function nonlinear uncertain system optimality.
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Particle filter with importance density function generated by updated system equation 被引量:3
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作者 左军毅 贾颖娜 +1 位作者 张炜 高全学 《Journal of Central South University》 SCIE EI CAS 2013年第10期2700-2707,共8页
The current measurement was exploited in a more efficient way. Firstly, the system equation was updated by introducing a correction term, which depends on the current measurement and can be obtained by running a subop... The current measurement was exploited in a more efficient way. Firstly, the system equation was updated by introducing a correction term, which depends on the current measurement and can be obtained by running a suboptimal filter. Then, a new importance density function(IDF) was defined by the updated system equation. Particles drawn from the new IDF are more likely to be in the significant region of state space and the estimation accuracy can be improved. By using different suboptimal filter, different particle filters(PFs) can be developed in this framework. Extensions of this idea were also proposed by iteratively updating the system equation using particle filter itself, resulting in the iterated particle filter. Simulation results demonstrate the effectiveness of the proposed IDF. 展开更多
关键词 IMPORTANCE density function nonlinear dynamic systems SEQUENCE IMPORTANCE sampling particle filter MONTE Carlo STEP
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Fuzzy Adaptive Control of Stochastic Nonlinear Systems with Unknown Virtual Control Gain Function 被引量:11
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作者 WANG Ying-Chun ZHANG Hua-Guang WANG Yi-Zhong 《自动化学报》 EI CSCD 北大核心 2006年第2期170-178,共9页
The problem of track control is studied for a class of strict-feedback stochastic nonlinear systems in which unknown virtual control gain function is the main feature. First, the so-called stochastic LaSalle theory is... The problem of track control is studied for a class of strict-feedback stochastic nonlinear systems in which unknown virtual control gain function is the main feature. First, the so-called stochastic LaSalle theory is extended to some extent, and accordingly, the results of global ultimate boundedness for stochastic nonlinear systems are developed. Next, a new design scheme of fuzzy adaptive control is proposed. The advantage of it is that it does not require priori knowledge of virtual control gain function sign, which is usually demanded in many designs. At the same time, the track performance of closed-loop systems is improved by adaptive modifying the estimated error upper bound. By theoretical analysis, the signals of closed-loop systems are globally ultimately bounded in probability and the track error converges to a small residual set around the origin in 4th-power expectation. 展开更多
关键词 随机非线性系统 模糊自适应控制 虚拟控制 增益函数
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Delay-dependent H∞ Control for T-S Fuzzy Systems Based on a Switching Fuzzy Model and Piecewise Lyapunov Function 被引量:5
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作者 XIA Zhi-Le LI Jun-Min 《自动化学报》 EI CSCD 北大核心 2009年第9期1235-1239,共5页
关键词 时延 模糊系统 线性矩阵不等式 分段LYAPUNOV函数
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Hopping Wave Function in Quantum Kicked Systems
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作者 CHONG Gui-shu,HAI Wen-huaCorrespondence Author (1.Department of Physics, Hunan Normal University, Changsha, 410081, China) 《原子与分子物理学报》 CAS CSCD 北大核心 2003年第1期107-113,共7页
A model of a kicked particle in an infinite potential well is studied. We presented the wave functions of the system applying a direct perturbation method. Theoretical analyses and numerical calculations show that the... A model of a kicked particle in an infinite potential well is studied. We presented the wave functions of the system applying a direct perturbation method. Theoretical analyses and numerical calculations show that the wave function is discontinuous across each kicking instant. As an extension of this result, we find that the wave function of any periodically kicked system usually has this property. Therefore, at each kicking instant, the wave function chooses randomly between the limits on either side and may be hopping. 展开更多
关键词 原子物理学 结构 波函数 量子体系
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构网型技术:演进历程、功能定位与应用展望 被引量:14
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作者 王伟 周少泽 +4 位作者 黄萌 艾诚 李奕曈 韦徵 郑玉平 《电力系统自动化》 北大核心 2025年第1期1-13,共13页
为支撑新能源高效利用和电力保供,构网型技术在电力系统不同应用场景中已获得初步探索实践。为促进构网型技术的规模化应用,文中探讨了构网型技术在新型电力系统中的功能定位和应用发展方向。通过梳理构网型技术的演进历程,以及国内外... 为支撑新能源高效利用和电力保供,构网型技术在电力系统不同应用场景中已获得初步探索实践。为促进构网型技术的规模化应用,文中探讨了构网型技术在新型电力系统中的功能定位和应用发展方向。通过梳理构网型技术的演进历程,以及国内外现有的标准和规范,分析了构网型技术发展的内在驱动需求,明晰了不同形态电网场景下构网型技术的功能定位;最后,从静、动、暂态的稳定性分析等维度,剖析了构网型技术当前面临的挑战,并对其大规模应用所需解决的问题进行了展望。 展开更多
关键词 构网型控制 构网型装备 新型电力系统 新能源 功能定位
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机场智慧飞行区愿景与架构 被引量:1
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作者 刘诗福 赵鸿铎 +1 位作者 郝航程 凌建明 《同济大学学报(自然科学版)》 北大核心 2025年第1期75-82,共8页
针对目前机场飞行区运行现状及管理使用的需求,结合《智慧民航建设路线图》和未来科技发展趋势,明确了机场智慧飞行区运行愿景。在此基础上,进一步诠释与梳理智慧飞行区的架构。智慧飞行区以智能物理要素为基础,以功能系统为支撑,组织... 针对目前机场飞行区运行现状及管理使用的需求,结合《智慧民航建设路线图》和未来科技发展趋势,明确了机场智慧飞行区运行愿景。在此基础上,进一步诠释与梳理智慧飞行区的架构。智慧飞行区以智能物理要素为基础,以功能系统为支撑,组织相关业务模块,最终保障运行愿景的实现。最后,系统分析了智慧飞行区在场面运行、设施管养、地勤服务、应急救援、能源保障方面的发展方向,提出了有效支撑智慧飞行区安全、效率、效益、环保的业务组织模式,对未来智慧飞行区的规划与应用具有重要参考意义和价值。 展开更多
关键词 智慧飞行区 愿景 架构 功能系统 业务模块
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Function Analyses of Geographic Information System on Rural Distribution Network
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作者 FANG Junlong FAN Yongcun +1 位作者 ZHANG Chunmei GU Shumin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第2期178-181,共4页
With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution n... With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution network, in order to develop rural distribution network. 展开更多
关键词 function analyses geographic information system distribution network
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基于自适应滑模控制器的PMSM调速策略研究 被引量:1
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作者 王要强 王秋旭 +2 位作者 聂福全 张晓光 梁军 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期88-94,共7页
为了提高永磁同步电机的调速性能,滑模控制逐渐取代PI控制被引入控制系统中。但是传统滑模控制中趋近律的趋近速度慢与固有抖振问题制约着滑模控制的发展,为此提出一种改进的滑模趋近律。首先,为了解决传统等速趋近律中趋近速度和抖振... 为了提高永磁同步电机的调速性能,滑模控制逐渐取代PI控制被引入控制系统中。但是传统滑模控制中趋近律的趋近速度慢与固有抖振问题制约着滑模控制的发展,为此提出一种改进的滑模趋近律。首先,为了解决传统等速趋近律中趋近速度和抖振难以平衡的问题,在所提趋近律中引入系统状态变量,并在滑模增益中引入指数项,使其在保证趋近速度的同时抑制滑模抖振。其次,由于开关函数在零点附近具有不连续的特性,会引起滑模抖振,为此采用sat函数代替常规开关函数,能够在保证响应速度的前提下抑制滑模抖振。然后,基于所提趋近律,设计永磁同步电机的滑模速度控制器。最后,仿真和实验结果表明,所提趋近律可以提高永磁同步电机调速系统的控制性能。 展开更多
关键词 永磁同步电机 滑模控制 自适应趋近律 sat函数 系统状态量
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营养治疗对ARDS病人肺-肠-免疫系统轴的影响 被引量:1
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作者 王洁 许惠仙 《肠外与肠内营养》 北大核心 2025年第2期113-118,共6页
营养支持在重症病人中的应用日益广泛,因其对肠道功能及相关免疫系统具有益处。ARDS病人易出现肠道菌群紊乱和肠道功能损伤,这有利于肠道致病菌通过“肠-肺”轴进入ARDS病人的肺部,激活相关免疫系统,加重ARDS病人的肺损伤,因此恢复ARDS... 营养支持在重症病人中的应用日益广泛,因其对肠道功能及相关免疫系统具有益处。ARDS病人易出现肠道菌群紊乱和肠道功能损伤,这有利于肠道致病菌通过“肠-肺”轴进入ARDS病人的肺部,激活相关免疫系统,加重ARDS病人的肺损伤,因此恢复ARDS病人肠道内环境的稳定以及免疫系统功能的正常发挥具有重要意义。本文综述了营养支持如何通过肺-肠-免疫系统轴影响ARDS病人的肠道黏膜屏障功能及免疫系统,并探讨了相关营养元素的作用机制。 展开更多
关键词 营养支持 ARDS 肠道功能 免疫系统
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高校教学督导制度的伦理审视:价值、缺失与回归 被引量:1
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作者 王芳亮 朱萍 《教育理论与实践》 北大核心 2025年第9期50-55,共6页
教学督导制度是高校内部教学质量治理的“利器”,其在诊断反馈、监督检查、评价改进中起着非常重要的作用。伦理思想之于高校教学督导制度具有独特的价值意蕴,它是高校教学督导实践向善的基点、高校教学督导制度合理的前提、高校教学督... 教学督导制度是高校内部教学质量治理的“利器”,其在诊断反馈、监督检查、评价改进中起着非常重要的作用。伦理思想之于高校教学督导制度具有独特的价值意蕴,它是高校教学督导实践向善的基点、高校教学督导制度合理的前提、高校教学督导文化和谐的保障。然而,现实中的高校教学督导制度在督导功能、督导模式、督导程序、督导主体和督导关系方面存在着种种伦理缺失,出现工具理性对价值理性的儹越、重效率轻公平、教师正当权益缺失、评价权制约教学自主权、评价双方关系对立等现象,遮蔽了教学督导育人、爱人和助人的本真伦理价值。为实现高校教学督导制度的伦理回归,应追求工具理性与价值理性的统一、效率与公平的统一、效能价值与程序价值的统一、能力与道德的统一、信任与对话的统一。 展开更多
关键词 高校 教学督导制度 伦理 督导功能 督导模式 督导程序 督导主体 督导关系
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