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Measuring the Sky with Rulers:Research on the Records of Astronomical Phenomena Observed with the Naked Eye in the Scale System in Chinese Sources
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作者 WANG Yumin 《Chinese Annals of History of Science and Technology》 2025年第2期1-57,共57页
In pre-modern China,systematic records of astronomical phenomena measured by units including“zhang,”“chi,”and“cun”and records using phrases such as“as large as something”(making comparison with images取象比类)... In pre-modern China,systematic records of astronomical phenomena measured by units including“zhang,”“chi,”and“cun”and records using phrases such as“as large as something”(making comparison with images取象比类)were kept.Some of these records survive and together they constitute a“scale system”for records of astronomical phenomena.A textual model of the celestial sphere based on naked eye observations also survives.According to this model and using the conversion ratio that 1 chi equals 1 degree,the author has reconstituted the geometric meaning of the records of“zhang,”“chi,”and“cun,”while records that use a comparison with a certain object have been converted to their apparent diameters or magnitudes.Finally,these two records are integrated into one system.Through an analysis of the origin of the chi system,the author obtains the result that the radius of the celestial sphere when the ancients observed the sky with the naked eye was about 13 meters.The paper supports this conclusion from various perspectives,including psychological factors,the radius of planetariums,and the nautical Method of Reckoning by the Stars.As naked eye observers always regard the vault of heaven as a plane hemisphere,they have a common false impression in their minds;the pre-modern observational data therefore contains some systematic errors.Under different illumination and weather conditions,the vault of heaven is plane in varying degrees,for which the author has defined“the angle of apparent plane degree”视扁度角.To correct the visual errors,the author has devised a series of calculation tables for daytime,nighttime,cloudy days,clear days,moonlit nights,and moonless nights,to convert the apparent heights or sizes of celestial bodies to the true heights or sizes. 展开更多
关键词 observe with naked eyes astronomical phenomena scale system celestial sphere plane quantification correction
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Decentralized robust guaranteed cost control for a class of interconnected singular large-scale systems with time-delay and parameter uncertainty 被引量:8
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作者 Wo Songlin Shi Guodong Zou Yun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期111-119,共9页
The decentralized robust guaranteed cost control problem is studied for a class of interconnected singular large-scale systems with time-delay and norm-bounded time-invariant parameter uncertainty under a given quadra... The decentralized robust guaranteed cost control problem is studied for a class of interconnected singular large-scale systems with time-delay and norm-bounded time-invariant parameter uncertainty under a given quadratic cost performance function. The problem that is addressed in this study is to design a decentralized robust guaranteed cost state feedback controller such that the closed-loop system is not only regular, impulse-free and stable, but also guarantees an adequate level of performance for all admissible uncertainties. A sufficient condition for the existence of the decentralized robust guaranteed cost state feedback controllers is proposed in terms of a linear matrix inequality (LMI) via LMI approach. When this condition is feasible, the desired state feedback decentralized robust guaranteed cost controller gain matrices can be obtained. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 Uncertain singular large-scale systems Time-delay system Guaranteed cost control LMI
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Modeling Research on Manufacturing Execution System Based on Large-scale System Cybernetics 被引量:1
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作者 吴瑜 许晓栋 李从心 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第6期744-747,共4页
A cybernetics model of manufacturing execution system(MES CM) was proposed and studied from the viewpoint of cybernetics.Combining with the features of manufacturing system, the MES CM was modeled by"generalized ... A cybernetics model of manufacturing execution system(MES CM) was proposed and studied from the viewpoint of cybernetics.Combining with the features of manufacturing system, the MES CM was modeled by"generalized modeling"method that is discussed in large-scale system theory.The mathematical model of MES CM was constructed by the generalized operator model, and the main characteristics of MES CM were analyzed. 展开更多
关键词 CYBERNETICS manufacturing execution system large scale system
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Optimal tracking control for nonlinear large-scale systems with persistent disturbances 被引量:1
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作者 Ruichun TANG Xianmin LU +1 位作者 Yili ZHAI Cunqun GONG 《控制理论与应用(英文版)》 EI 2010年第4期515-520,共6页
This paper studies the optimal control with zero steady-state error problem for nonlinear large-scale systems affected by external persistent disturbances.The nonlinear large-scale system is transformed into N nonline... This paper studies the optimal control with zero steady-state error problem for nonlinear large-scale systems affected by external persistent disturbances.The nonlinear large-scale system is transformed into N nonlinear subsystems with interconnect terms.Based on the internal model principle,a disturbance compensator is constructed such that the ith subsystem with external persistent disturbances is transformed into an augmented subsystem without disturbances.According to the sensitivity approach,the optimal tracking control law for the ith nonlinear subsystem can be obtained.The optimal tracking control law for the nonlinear large-scale systems can be obtained.A numerical simulation shows that the method is effective. 展开更多
关键词 Nonlinear systems Large-scale systems Persistent disturbances Optimal tracking control Sensitivity approach
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Optimal tracking control for linear time-delay large-scale systems with persistent disturbances 被引量:1
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作者 Tang Ruichun Ma Huamin +1 位作者 Guo Shuangle Ren Lijie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期1058-1064,共7页
An optimal tracking control (OTC) problem for linear time-delay large-scale systems affected by external persistent disturbances is investigated. Based on the internal model principle, a disturbance compensator is c... An optimal tracking control (OTC) problem for linear time-delay large-scale systems affected by external persistent disturbances is investigated. Based on the internal model principle, a disturbance compensator is constructed. The system with persistent disturbances is transformed into an augmented system without persistent disturbances. The original OTC problem of linear time-delay system is transformed into a sequence of linear two- point boundary value (TPBV) problems by introducing a sensitivity parameter and expanding Maclaurin series around it. By solving an OTC law of the augmented system, the OTC law of the original system is obtained. A numerical simulation is provided to illustrate the effectiveness of the proposed method. 展开更多
关键词 optimal tracking control sensitivity approach time-delay large-scale system persistent disturbance
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Decentralized robust stabilization of discrete-time fuzzy large-scale systems with parametric uncertainties: a LMI method 被引量:1
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作者 Zhang Yougang Xu Bugong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期836-845,共10页
Decentralized robust stabilization problem of discrete-time fuzzy large-scale systems with parametric uncertainties is considered. This uncertain fuzzy large-scale system consists of N interconnected T-S fuzzy subsyst... Decentralized robust stabilization problem of discrete-time fuzzy large-scale systems with parametric uncertainties is considered. This uncertain fuzzy large-scale system consists of N interconnected T-S fuzzy subsystems, and the parametric uncertainties are unknown but norm-bounded. Based on Lyapunov stability theory and decentralized control theory of large-scale system, the design schema of decentralized parallel distributed compensation (DPDC) fuzzy controllers to ensure the asymptotic stability of the whole fuzzy large-scale system is proposed. The existence conditions for these controllers take the forms of LMIs. Finally a numerical simulation example is given to show the utility of the method proposed. 展开更多
关键词 fuzzy large-scale system parametric uncertainties decentralized Parallel distributed compensation linear matrix inequalities.
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ON DECENTRALIZED STABILIZATION OF LINEAR LARGE SCALE SYSTEMS WITH SYMMETRIC CIRCULANT STRUCTURE
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作者 金朝永 张湘伟 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第8期863-872,共10页
The decentralized stabilization of continuous and discrete linear large scale systems with symmetric circulant structure was studied.A few sufficient conditions on decentralized stabilization of such systems were prop... The decentralized stabilization of continuous and discrete linear large scale systems with symmetric circulant structure was studied.A few sufficient conditions on decentralized stabilization of such systems were proposed.For the continuous systems,by introducing a concept called the magnitude of interconnected structure,a very important property that the decentralized stabilization of such systems is fully determined by the structure of each isolated subsystem that is obtained when the magnitude of interconnected structure of the overall system is given.So the decentralized stabilization of such systems can be got by only appropriately designing or modifying the structure of each isolated subsystem,no matter how complicated the interconnected structure of the overall system is.A algorithm for obtaining decentralized state feedback to stabilize the overall system is given.The discrete systems were also discussed.The results show that there is a great dfference on decentralized stabilization between continuous case and discrete case. 展开更多
关键词 large scale system decentralized stabilization symmetric circulant structure magnitude of interconnected structure Ricatti equation
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Advances of Model Order Reduction Research in Large-scale System Simulation
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作者 SUN Dao-heng, MA Hai-yang, WANG Yan-hua (Department of Mechanical and Electrical Engineering, Xiamen Universi ty, Xiamen 361005, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期174-,共1页
Model Order Reduction (MOR) plays more and more imp or tant role in complex system simulation, design and control recently. For example , for the large-size space structures, VLSI and MEMS (Micro-ElectroMechanical Sys... Model Order Reduction (MOR) plays more and more imp or tant role in complex system simulation, design and control recently. For example , for the large-size space structures, VLSI and MEMS (Micro-ElectroMechanical Systems) etc., in order to shorten the development cost, increase the system co ntrolling accuracy and reduce the complexity of controllers, the reduced order model must be constructed. Even in Virtual Reality (VR), the simulation and d isplay must be in real-time, the model order must be reduced too. The recent advances of MOR research are overviewed in the article. The MOR theor y and methods may be classified as Singular Value decomposition (SVD) based, the Krylov subspace based and others. The merits and demerits of the different meth ods are analyzed, and the existed problems are pointed out. Moreover, the applic ation’s fields are overviewed, and the potential applications are forecaste d. After the existed problems analyzed, the future work is described. There are som e problems in the traditional methods such as SVD and Krylov subspace, they are that it’s difficult to (1)guarantee the stability of the original system, (2) b e adaptive to nonlinear system, and (3) control the modeling accuracy. The f uture works may be solving the above problems on the foundation of the tradition al methods, and applying other methods such as wavelet or signal compression. 展开更多
关键词 model order reduction large-scale system SVD krylov
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THE ASYMPTOTIC STABILITY OF THE LINEAR.DISCRETE LARGE-SCALE SYSTEMS
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作者 胡朝阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第1期95-100,共6页
In this paper, we directly use the tirear norm Liapunov function to investigate the stability of the linear discrete large-scale systems and obtain some criteria for the asymptotic stability of such a system.
关键词 discrete large-scale systems STABILITY Liapunov function
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Optimal decentralized control of large scale systems
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作者 Xiao Qi SHI Daniel E. DAVISON +1 位作者 Raymond KWONG Edward J. DAVISON 《Control Theory and Technology》 EI CSCD 2016年第4期287-313,共27页
This paper presents a new optimized decentralized controller design method for solving the tracking and disturbance rejection problems for large-scale linear time-invariant systems, using only low-order decentralized ... This paper presents a new optimized decentralized controller design method for solving the tracking and disturbance rejection problems for large-scale linear time-invariant systems, using only low-order decentralized controllers. To illustrate the type of results which can be obtained using the new optimized decentralized control design method, the control of a large flexible space structure is studied and compared with the standard centralized LQR-observer controller. The order of the resultant decentralized controller is much smaller than that of the standard centralized LQR-observer controller. The proposed controller also has certain fail-safe properties and, in addition, it can be five orders of magnitude more robust than the standard LQR-observer controller based on their real stability radii. The new decentralized controller design method is applied to a large flexible space structure system with 5 inputs and 5 outputs and of order 24. 展开更多
关键词 Decentralized control multivariable control PID control ROBUSTNESS OPTIMIZATION large-scale systems flexiblestructures
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Partial stability of a class of large-scale systems with partiallystable isolated subsystems
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作者 JianJigui LuoHaigeng LiaoXiaoxin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期346-350,共5页
The problem of partial stability is investigated for a class of continuous-time large-scale systems. Under assumption that the null solution of the isolated subsystems is stable, based on decomposition-aggregation met... The problem of partial stability is investigated for a class of continuous-time large-scale systems. Under assumption that the null solution of the isolated subsystems is stable, based on decomposition-aggregation methods and Lyapunov second method, some theorems concerning the globally partial asymptotic stability and globally partial exponential stability are obtained via utilizing the inequality analysis technique and comparison technique. Finally, an example is presented to illustrate the results. 展开更多
关键词 large-scale systems partial stability INEQUALITY comparison principle Lyapunov function.
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ON DECENTRALIZED OBSERVATION AND DECENTRALIZED CONTROL OF LARGE SCALE SYSTEMS
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作者 蔚润义 高为炳 《Acta Mathematica Scientia》 SCIE CSCD 1991年第2期136-141,共6页
In this paper, the problem of decentralized observation and decentralized control of linear, time-invariant large scale systems is studied. Based on conventional observer theory, the necessary and sufficient condition... In this paper, the problem of decentralized observation and decentralized control of linear, time-invariant large scale systems is studied. Based on conventional observer theory, the necessary and sufficient conditions for existence of completely decentralized observer are obtained. Moreover, the necessary and sufficient condition is given for stabilization of large scale systems by local output with state of the subsystem estimated through the completely decentralized observer. 展开更多
关键词 ON DECENTRALIZED OBSERVATION AND DECENTRALIZED CONTROL OF LARGE scale systemS
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Distributed Model Predictive Control with One-Step Delay Communication for Large-Scale Systems and a Case Study
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作者 张艳 徐成 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第6期747-754,共8页
A distributed model predictive control(MPC) scheme with one-step delay communication is proposed for on-line optimization and control of large-scale systems in this paper. Cooperation between subsystems is achieved by... A distributed model predictive control(MPC) scheme with one-step delay communication is proposed for on-line optimization and control of large-scale systems in this paper. Cooperation between subsystems is achieved by exchanging information with neighbor-to-neighbor communication and by optimizing the local problem with the improved performance index in the neighborhood. A distributed MPC algorithm with one-step delay communication is developed for the situation that there is a one-step delay in the information available from its neighbors when a subsystem solves the local optimization problem. The nominal stability is employed for the whole system under the distributed MPC algorithm without the inequality constraints. Finally, the case study of the reactor-storage-separator(RSS) system is illustrated to test the practicality of the presented control algorithm. 展开更多
关键词 large-scale systems model predictive control(MPC) exchange information one-step delay communication reactor-storage-separator(RSS)
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Robust non-fragile control for discrete-delay nonlinear large-scale systems
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作者 吴忠强 李卓 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第4期481-485,共5页
Time-delays,due to the information transmission between subsystems,naturally exist in large-scale systems and the existence of the delay is frequently a source of instability. This paper considers the problems of robu... Time-delays,due to the information transmission between subsystems,naturally exist in large-scale systems and the existence of the delay is frequently a source of instability. This paper considers the problems of robust non-fragile fuzzy control for a class of uncertain discrete nonlinear large-scale systems with time-delay and controller gain perturbations described by T-S fuzzy model. An equivalent T-S fuzzy model is represented for discrete-delay nonlinear large-scale systems. A sufficient condition for the existence of such non-fragile controllers is further derived via the Lyapunov function and the linear matrix inequality( LMI) approach. Simulation results demonstrate the feasibility and the effectiveness of the proposed design and the proper stabilization of the system in spite of controller gain variations and uncertainties. 展开更多
关键词 non-fragile control discrete-delay nonlinear large-scale systems T-S fuzzy model linear matrix inequality
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Stability Analysis of Continuous-Time Fuzzy Large-Scale System
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作者 曾怡达 张友刚 肖建 《Journal of Southwest Jiaotong University(English Edition)》 2003年第2期144-151,共8页
A continuous-time fuzzy large-scale system F consists of some interconnected Takagi-Sugeno fuzzy subsystems. Two sufficient conditions for the asymptotic stability of this system (namely, theorem 1 and theorem 2) are... A continuous-time fuzzy large-scale system F consists of some interconnected Takagi-Sugeno fuzzy subsystems. Two sufficient conditions for the asymptotic stability of this system (namely, theorem 1 and theorem 2) are derived via a multiple Lyapunov function approach. In theorem 1, the information of membership functions of fuzzy rules should be known in order to analyze the stability of F. But in general this information is not easy to be acquired for their time-varying property. So theorem 2 is provided to judge the asymptotic stability of F, based on which there is no need to know the information of membership functions in stability analysis. Finally, a numerical example is given to show the utility of the method proposed in this paper. 展开更多
关键词 fuzzy large-scale system stability analysis Takagi-Sugeno fuzzy model multiple Lyapunov funcion
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Optimal Control for Nonlinear Interconnected Large-scale Systems: A Successive Approximation Approach 被引量:30
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作者 唐功友 孙亮 《自动化学报》 EI CSCD 北大核心 2005年第2期248-254,共7页
The optimal control problem for nonlinear interconnected large-scale dynamic systems is considered. A successive approximation approach for designing the optimal controller is proposed with respect to quadratic perfor... The optimal control problem for nonlinear interconnected large-scale dynamic systems is considered. A successive approximation approach for designing the optimal controller is proposed with respect to quadratic performance indexes. By using the approach, the high order, coupling,nonlinear two-point boundary value (TPBV) problem is transformed into a sequence of linear decoupling TPBV problems. It is proven that the TPBV problem sequence uniformly converges to the optimal control for nonlinear interconnected large-scale systems. A suboptimal control law is obtained by using a finite iterative result of the optimal control sequence. 展开更多
关键词 非线性 互联大系统 最优控制 逐次逼近法
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Stabilization for a Class of Discrete-time Switched Large-scale Systems with Parameter Uncertainties 被引量:2
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作者 Chang-Chun Sun 《International Journal of Automation and computing》 EI CSCD 2019年第4期543-552,共10页
The problem of robust stabilization for a class of discrete-time switched large-scale systems with parameter uncertainties and nonlinear interconnected terms is considered. By using state feedback and Lyapunov functio... The problem of robust stabilization for a class of discrete-time switched large-scale systems with parameter uncertainties and nonlinear interconnected terms is considered. By using state feedback and Lyapunov function technique, a decentralized switching control approach is put forward to guarantee the solutions of large-scale systems converge to the origin globally. A numerical example and a corresponding simulation result are utilized to verify the effectiveness of the presented approach. 展开更多
关键词 SWITCHED large-scale systems DISCRETE-TIME state feedback DECENTRALIZED control SWITCHING LAW
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Decentralized Iterative Learning Controllers for Nonlinear Large-scale Systems to Track Trajectories with Different Magnitudes 被引量:3
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作者 RUAN Xiao-E CHEN Feng-Min WAN Bai-Wu 《自动化学报》 EI CSCD 北大核心 2008年第4期426-432,共7页
在为大规模工业进程的层次不变的优化编程,一种可行技术是使用真实系统的信息以便修改基于模型的最佳。在这种情形,有不同大小的步功能类型控制决定的一个序列被计算,由哪个真实系统连续地被刺激。在这份报纸,一套反复的学习控制器... 在为大规模工业进程的层次不变的优化编程,一种可行技术是使用真实系统的信息以便修改基于模型的最佳。在这种情形,有不同大小的步功能类型控制决定的一个序列被计算,由哪个真实系统连续地被刺激。在这份报纸,一套反复的学习控制器为大规模非线性的工业过程的一个班在分散的模式被嵌进层次不变的优化的过程。为每个分系统的控制器被用来产生升级的控制信号的一个序列以便与不同规模承担顺序的步骤控制决定的责任。学习控制设计的目的是连续地精制系统的短暂性能。借助于卷绕旋转积分的 Hausdorff 年轻的不平等,更新的规则的集中在 Lebesgue-p 标准的意义被分析。集中上的非线性和相互作用的发明被讨论。建议控制计划的有效性和有效性被一些模拟表明。 展开更多
关键词 恒星 非线性控制系统 轨迹 星等
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Sample-data Decentralized Reliable H∞ Hyperbolic Control for Uncertain Fuzzy Large-scale Systems with Time-varying Delay 被引量:2
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作者 LIU Xin-Rui ZHANG Hua-Guang 《自动化学报》 EI CSCD 北大核心 2009年第12期1534-1540,共7页
这份报纸学习样品数据的问题为有变化时间的延期的不明确的连续时间的模糊大规模系统的可靠 H 夸张控制。第一,模糊夸张模型( FHM )被用来为某些复杂大规模系统建立模型,然后根据 Lyapunov 指导方法和大规模系统的分散的控制理论,线... 这份报纸学习样品数据的问题为有变化时间的延期的不明确的连续时间的模糊大规模系统的可靠 H 夸张控制。第一,模糊夸张模型( FHM )被用来为某些复杂大规模系统建立模型,然后根据 Lyapunov 指导方法和大规模系统的分散的控制理论,线性 matrixine 质量( LMI )基于条件 arederived toguarantee H 性能不仅当所有控制部件正在操作很好时,而且面对一些可能的致动器失败。而且,致动器的精确失败参数没被要求,并且要求仅仅是失败参数的更低、上面的界限。条件依赖于时间延期的上面的界限,并且不依赖于变化时间的延期的衍生物。因此,获得的结果是不太保守的。最后,二个例子被提供说明设计过程和它的有效性。 展开更多
关键词 模糊双曲模型 线性矩阵不等式 分散控制理论 执行器
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Analysis on the Meso-scale System Activity and the Structure Characteristics of A Short-time Rainstorm 被引量:3
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作者 黄卓禹 刘志雄 +2 位作者 肖妙妮 沈安云 吴艳林 《Meteorological and Environmental Research》 CAS 2010年第9期57-61,66,共6页
By using the rainfall data in the regional automatic station,FY-2E satellite data,NCEP reanalysis data,the evolution features and the structure characteristics of a meso-scale convective system(MCS) which happened on ... By using the rainfall data in the regional automatic station,FY-2E satellite data,NCEP reanalysis data,the evolution features and the structure characteristics of a meso-scale convective system(MCS) which happened on May 6 in 2010 in Loudi City of Hunan Province were analyzed.The results showed that MCS was the important influence system for the generation and development of strong precipitation.The equivalent blackbody brightness temperature(TBB) field of satellite inversion could directly reflect the convective activity of cumulus,the precipitation distribution and the intensity characteristics in the rainstorm process.TBB low value belt had the good corresponding relationship with the rainstorm falling zone.The disturbance flow field and the height field which passed Barnes band-pass wave filtering represented that there existed the obvious high-layer anticyclonic circulation and the low-layer cyclonic circulation near the rainstorm zone.The divergence in the high layer and the convergence in the low layer enhanced the occurrence and development of MCS.In addition,the disturbance temperature field revealed the main source of energy which the occurrence and development of strong convective weather needed. 展开更多
关键词 Meso-scale convective system Strong precipitation TBB Barnes band-pass wave filtering China
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