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Edge modes in finite-size systems with different edge terminals
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作者 Huiping Wang Li Ren +1 位作者 Xiuli Zhang Liguo Qin 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期381-387,共7页
We investigate the behavior of edge modes in the presence of different edge terminations and long-range(LR)hopping.Here,we mainly focus on such model crystals with two different types of structures(type I:“…-P-Q-P-Q... We investigate the behavior of edge modes in the presence of different edge terminations and long-range(LR)hopping.Here,we mainly focus on such model crystals with two different types of structures(type I:“…-P-Q-P-Q-…”and type II:“…=P-Q=P-Q=…”),where P and Q represent crystal lines(CLs),while the symbols“-”and“=”denote the distance between the nearest neighbor(NN)CLs.Based on the lattice model Hamiltonian with LR hopping,the existence of edge modes is determined analytically by using the transfer matrix method(TMM)when different edge terminals are taken into consideration.Our findings are consistent with the numerical results obtained by the exact diagonalization method.We also notice that edge modes can exhibit different behaviors under different edge terminals.Our result is helpful in solving novel edge modes in honeycomb crystalline graphene and transition metal dichalcogenides with different edge terminals. 展开更多
关键词 edge modes long-range hopping different edge terminals
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Land Use Dynamics and Ecosystem Service Value Changes in the Yangtze River Delta Urban Agglomeration Under Different Scenarios
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作者 HE Xiangmei LI Jialin +4 位作者 GUAN Jian LIU Yongchao TIAN Peng AI Shunyi GONG Hongbo 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1105-1118,共14页
Urban agglomerations,serving as pivotal centers of human activity,undergo swift alterations in ecosystem services prompted by shifts in land utilization.Strengthening the monitoring of ecosystem services in present an... Urban agglomerations,serving as pivotal centers of human activity,undergo swift alterations in ecosystem services prompted by shifts in land utilization.Strengthening the monitoring of ecosystem services in present and future urban agglomerations contributes to the rational planning of these areas and enhances the well-being of their inhabitants.Here,we analyzed land use conversion in the Yangtze River Delta(YRD)urban agglomeration during 1990-2020 and discussed the spatiotemporal response and main drivers of changes in ecosystem service value(ESV).By considering the different development strategic directions described in land use planning policies,we predicted land use conversion and its impact on ESV using the Future Land Use Simulation(FLUS)model in three scenari-os in 2025 and 2030.Results show that:1)from 1990 to 2020,land use change is mainly manifested as the continuous expansion of con-struction land to cultivated land.Among the reduced cultivated land,82.2%were occupied by construction land.2)The land use types conversion caused a loss of 21.85 billion yuan(RMB)in ESV during 1990-2020.Moreover,the large reduction of cultivated land area led to the continuous decline of food production value,accounting for 13%of the total ESV loss.3)From 2020 to 2030,land use change will mainly focus on Yangzhou and Zhenjiang in central Jiangsu Province and Taizhou in southern Zhejiang Province.Under the BAU(natural development)and ED(cultivated land protection)scenarios,construction land expansion remains dominant.In contrast,under the EP(ecological protection)scenario,the areas of water bodies and forest land increase significantly.Among the different scenarios,ESV is highest in the EP scenario,making it the optimal solution for sustainable land use.It can be seen that the space use conflict among urban,agriculture and ecology is a key factor leading to ESV change in the urban agglomeration of Yangtze River Delta.There-fore,it is crucial to maintain spatial land use coordination.Our findings provide suggestions for scientific and rational land use planning for the urban agglomeration. 展开更多
关键词 land use Future Land Use Simulation(FLUS)model ecosystem service value(ESV) different scenarios Yangtze River Delta(YRD)urban agglomeration China
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Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Crop Yield and Soil K Under Different Planting Systems 被引量:25
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作者 TAN De-shui JIN Ji-yun HUANG Shao-wen LI Shu-tian HE Ping 《Agricultural Sciences in China》 CAS CSCD 2007年第2期200-207,共8页
Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertiliz... Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertilizer and wheat straw to soil in Hebei fluvo aquic soil and Shanxi brown soil in northern China were begun in 1992. The results showed that K fertilizer and straw could improve the yields of wheat and maize with the order of NPK + St 〉 NPK 〉 NP + St 〉 NP, and treatment of K fertilizer made a significant difference to NP, and the efficiency of K fertilizer in maize was higher than in wheat under rotation system of Hebei. In contrast with Shanxi, the wastage of soil potassium was a more serious issue in the rotation system in Hebei, only treatment of NPK + St showed a surplus of potassium and the others showed a wane. K fertilizer and straw could improve the content of water-soluble K, nonspecifically adsorbed K, non-exchangeable K, mineral K, and total K in contrast to NP; however, K fertilizer and straw reduce the proportion of mineral K and improve proportion of other forms of potassium in the two locating sites. Compared with the beginning of orientation, temporal variability character of soil K content and proportion showed a difference between the two soil types; furthermore, there was a decrease in the content of mineral K and total K simultaneously in the two locating sites. As a whole, the effect of K fertilizer applied to soil directly excelled to wheat straw to soil. Wheat straw to soil was an effective measure to complement potassium to increase crop yield and retard the decrease of soil K. 展开更多
关键词 different planting systems long-term application of K fertilizer wheat straw to soil crop yield soil K
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Synchronization of chaotic systems with different orders 被引量:14
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作者 吕翎 栾玲 郭治安 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期346-351,共6页
A controller is designed to realize the synchronization between chaotic systems with different orders. The structure of the controller, the error equations and the Lyapunov functions are determined based on stability ... A controller is designed to realize the synchronization between chaotic systems with different orders. The structure of the controller, the error equations and the Lyapunov functions are determined based on stability theory. Hyperchaotic Chen system and Rossler system are taken for example to demonstrate the method to be effective and feasible. Simulation results show that all the state wriables of Rossler system can be synchronized with those of hyperchaotic Chen system by using only one controller, and the error signals approach zero smoothly and quickly. 展开更多
关键词 chaos synchronization hyperchaotic Chen system Rossler system chaotic systems with different orders
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Gas drainage from different mine of drainage systems for deep coal areas: optimal placement seams with high gas emissions 被引量:10
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作者 Ping Lu Ping Li +3 位作者 Jian Chen Chuijin Zhang Junhua Xue Tao Yu 《International Journal of Coal Science & Technology》 EI 2015年第1期84-90,共7页
The techniques of stress relief mining in low-permeability coal seams and pillarless gob side retained roadway entry using Y-type ventilation and gas drainage systems were developed to control gas outbursts and applie... The techniques of stress relief mining in low-permeability coal seams and pillarless gob side retained roadway entry using Y-type ventilation and gas drainage systems were developed to control gas outbursts and applied successfully. However, as the mining depth increasing, parts of the gas drainage system are not suitable for mines with high gas emissions. Because larger mining depths cause higher ground stresses, it becomes extremely difficult to maintain long gob side roadways. The greater deformation suffered by the roadway is not favorable lor borehole drilling for continuous gas drainage. To solve these problems, Y-type ventilation and gas drainage systems installed from a roof roadway were designed for drainage optimization. This system was designed based on a gas-enrichment zone analysis developed from mining the 11-2 coal seam in the Zhuji Mine at Huainan, Anhui Province, China. The method of Y-type gas extraction from different mine areas was applied to the panel 1112(1) in the Zhuji Mine. The absolute gas emission rate was up to 116.3 m^3/min with an average flow of 69.1 m^3/min at an average drainage concentration of nearly 85 %. After the Y-type method was adopted, the concentration of gas in the return air was 0.15 %-0.64 %, averaging 0.39 % with a ventilation rate of 2100-2750 m^3/min. The gas management system proved to be efficient, and the effective gas control allowed safe production to continue . 展开更多
关键词 Gas drainage different gas sources Y-type ventilation Gob side retained roadway Gas emission Gas-enrichment zone
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CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS 被引量:3
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作者 丁小丽 Juan J.NIETO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1003-1013,共11页
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex... Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results. 展开更多
关键词 CONTROLLABILITY OPTIMALITY neutral equations different fractional orders
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MEROMORPHIC SOLUTIONS OF A TYPE OF SYSTEM OF COMPLEX DIFFERENTIAL-DIFFERENCE EQUATIONS 被引量:5
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作者 李海绸 高凌云 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期195-206,共12页
Applying Nevanlinna theory of the value distribution of meromorphic functions, we mainly study the growth and some other properties of meromorphic solutions of the type of system of complex differential and difference... Applying Nevanlinna theory of the value distribution of meromorphic functions, we mainly study the growth and some other properties of meromorphic solutions of the type of system of complex differential and difference equations of the following form {j=1∑nαj(z)f1(λj1)(z+cj)=R2(z,f2(z)),j=1∑nβj(z)f2(λj2)(z+cj)=R1(z,f1(z)). where λij (j = 1, 2,…, n; i = 1, 2) are finite non-negative integers, and cj (j = 1, 2,… , n) are distinct, nonzero complex numbers, αj(z), βj(z) (j = 1,2,… ,n) are small functions relative to fi(z) (i =1, 2) respectively, Ri(z, f(z)) (i = 1, 2) are rational in fi(z) (i =1, 2) with coefficients which are small functions of fi(z) (i = 1, 2) respectively. 展开更多
关键词 growth order system of equations complex differential equations difference equations Nevanlinna theory value distribution
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Fiber Migration and Distribution of Twist at Different Radial Positions of Rotor Yarn-by Hi-Scope Video Microscope System 被引量:5
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作者 王善元 CHEUNG H.W. +2 位作者 张宏伟 LO M.T. 卢明德 《Journal of Donghua University(English Edition)》 EI CAS 2002年第3期45-47,共3页
This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions o... This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions of tracer fibers were measured in three dimensions accurately, and the migration index and the twist distribution at different radial positions of rotor yarn were calculated and analyzed. This research result serves to provide useful references for further study on the structural mechanics of rotor spun yarn. 展开更多
关键词 rotor yarn fiber migration twist distribution at different radial positions.
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SUFFICIENT CONDITIONS FOR THE EXISTENCE OF PERIODIC SOLUTIONS OF A AUTONOMOUS DIFFERENTIAL SYSTEM 被引量:1
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作者 黄立宏 庚建设 《Acta Mathematica Scientia》 SCIE CSCD 1995年第2期126-135,共10页
In this paper, some sufficient conditions on the existence of non-trivial periodic solutions of the system dx/dt=e(y), dy/dt=- f(x)h(y)- g(x)are obtained, which not only generalize some known results concerning the Li... In this paper, some sufficient conditions on the existence of non-trivial periodic solutions of the system dx/dt=e(y), dy/dt=- f(x)h(y)- g(x)are obtained, which not only generalize some known results concerning the Lienard system in this direction, but also relax or eliminate some traditional assumptions. 展开更多
关键词 autonomous differental system periodic solution existence.
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EXISTENCE TIME FOR SOLUTIONS OFSEMILINEAR DIFFERENT SPEED KLEIN-GORDONSYSTEM WITH WEAK DECAY DATA IN 1D 被引量:2
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作者 方道元 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期79-98,共20页
A -4/3|log |-2 result is obtained for the existence time of solutions of semi- linear different speed Klein-Gordon system in one space dimension for weakly decaying Cauchy data, of size , in certain circumstances of ... A -4/3|log |-2 result is obtained for the existence time of solutions of semi- linear different speed Klein-Gordon system in one space dimension for weakly decaying Cauchy data, of size , in certain circumstances of nonlinearity. 展开更多
关键词 Weakly decaying Cauchy data existence time. Klein-Gordon equations with different speeds
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Adaptive generalized projective synchronization of two different chaotic systems with unknown parameters 被引量:1
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作者 张若洵 杨世平 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4073-4079,共7页
This paper presents a general method of the generalized projective synchronization and the parameter identification between two different chaotic systems with unknown parameters. This approach is based on Lyapunov sta... This paper presents a general method of the generalized projective synchronization and the parameter identification between two different chaotic systems with unknown parameters. This approach is based on Lyapunov stability theory, and employs a combination of feedback control and adaptive control. With this method one can achieve the generalized projective synchronization and realize the parameter identifications between almost all chaotic (hyperchaotic) systems with unknown parameters. Numerical simulations results are presented to demonstrate the effectiveness of the method. 展开更多
关键词 different chaotic systems generalized projective synchronization parameter identification unknown parameters
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Generalized Synchronization Between Different Fractional-Order Chaotic Systems 被引量:1
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作者 ZHOU Ping CHENG Xue-Feng ZHANG Nian-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期931-934,共4页
In this paper,using scalar feedback controller and stability theory of fractional-order systems,a gener-alized synchronization method for different fractional-order chaotic systems is established.Simulation results sh... In this paper,using scalar feedback controller and stability theory of fractional-order systems,a gener-alized synchronization method for different fractional-order chaotic systems is established.Simulation results show theeffectiveness of the theoretical results. 展开更多
关键词 generalized synchronization different fractional-order chaotic systems scalar controller
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3D Physical Simulation of Water Flooding Characteristics of Buried Hill Reservoir with Different Fracture Systems 被引量:1
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作者 Xiaolin Zhu Zhiqiang Meng +2 位作者 Pingzhi Gong Guanglong Li Xinran Wang 《Journal of Power and Energy Engineering》 2020年第5期1-13,共13页
In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional ... In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional physical model of fractured reservoirs is established according to the similarity criterion based on the prototype of metamorphic buried hill reservoirs in JZ Oilfield in Bohai Bay Basin. Combined with the fractured reservoir characteristics of JZ Oilfield, the water displacement characteristics of the top-bottom staggered injection-production well pattern in different fracture network mode and different fracture development degree of buried hill reservoir are studied. The experimental results show that: 1) the more serious the fracture system irregularity is, the shorter the water-free oil production period is and the lower the water-free oil recovery is. After water breakthrough of production wells, the water cut rises faster, and the effect of water flooding development is worse;2) under the condition of non-uniform fracture development, the development effect of the bottom fracture undeveloped is better than that of the middle fracture undeveloped. Water injection wells are deployed in areas with relatively few fractures, while oil wells are deployed in fractured areas with higher oil recovery and better development effect. 展开更多
关键词 METAMORPHIC Buried HILL Reservoir different FRACTURE systemS 3D Physical Simulation Water Flooding CHARACTERISTICS
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Design,test,and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment 被引量:1
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作者 Haichun Hao Mingzhong Gao +10 位作者 Yan Wu Zheng Gao Yongcheng Li Xuemin Zhou Peng Chu Xuan Wang Jiahua Li Lang Zhou Jie Song Tianxiang Ao Yikun Yang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1259-1272,共14页
The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and soci... The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and society.Technological exploration and research in the field of deep space science,especially lunar-based exploration,is a scientific strategy that has been pursued in China and worldwide.Drilling and sampling are key to accurate exploration of the desirable characteristics of deep lunar resources.In this study,an in-situ condition preserved coring(ICP-Coring)and analysis system,which can be used to test drilling tools and develop effective sampling strategies,was designed.The key features of the system include:(1)capability to replicate the extreme temperature fluctuations of the lunar environment(-185 to 200℃)with intelligent temperature control;(2)ability to maintain a vacuum environment at a scale of 10^(-3) Pa,both under unloaded conditions within Ф580 mm×1000 mm test chamber,and under loaded conditions using Ф400 mm×800 mm lunar rock simulant;(3)application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa;(4)sample rotation at any angle with a maximum sampling length of 800 mm;and(5)multiple modes of rotary-percussive drilling,controlled by penetration speed and weight on bit(WOB).Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were conducted.The results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated environment.The rotary-percussive drilling method effectively shortens the sampling time.With increasing sampling depth,the temperature rise of the drilling tools tends to rapidly increase,followed by slow growth or steady fluctuations.The temperature rise energy accumulation of the drill bits under vacuum is more significant than that under atmospheric pressure,approximately 1.47 times higher.The real-time monitored drilling pressure,penetration speed and rotary torque during drilling serve as parameters for discriminating the drilling status.The results of this research can provide a scientific basis for returning samples from lunar rock in extreme lunar-based environments. 展开更多
关键词 Lunar-based Large temperature difference Vacuum Drilling and coring system design
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Synchronization of N different coupled chaotic systems with ring and chain connections
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作者 刘艳 吕翎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第10期1299-1308,共10页
Synchronization of N different coupled chaotic systems with ring and chain connections is investigated. The New system, the Chen system, the Lii system, the Lorenz system, and the Rossler system are used as examples i... Synchronization of N different coupled chaotic systems with ring and chain connections is investigated. The New system, the Chen system, the Lii system, the Lorenz system, and the Rossler system are used as examples in verifying effectiveness of the method. Based on the Lyapunov stability theory, the form of the controller is designed and the area of the coupling coefficients is determined. Simulations indicate that global synchronization of the N different chaotic systems can be realized by choosing appropriate coupling coefficients by using the controller. 展开更多
关键词 chaos synchronization Lyapunov stability theory coupling with ring and chain connection different chaotic systems coupling coefficient
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Realization of generalized synchronization between different chaotic systems via scalar controller
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作者 周平 曹玉霞 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2903-2907,共5页
In this paper, a very simple generalized synchronization method between different chaotic systems is presented. Only a scalar controller is used in this method. The method of obtaining the scalar controller from chaot... In this paper, a very simple generalized synchronization method between different chaotic systems is presented. Only a scalar controller is used in this method. The method of obtaining the scalar controller from chaotic systems is established. The sufficient and necessary condition of generalized synchronization is obtained from a rigorous theory, and the sufficient and necessary condition of generalized synchronization is irrelative to chaotic system itself. Theoretical analyses and simulation results show that the method established in this paper is effective. 展开更多
关键词 generalized synchronization different chaotic systems scalar controller
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Fixed-Time Adaptive Time-Varying Matrix Projective Synchronization of Time-Delayed Chaotic Systems with Different Dimensions
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作者 Peng Zheng Xiaozhen Guo Guoguang Wen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1451-1463,共13页
This paper deals with the fixed-time adaptive time-varying matrix projective synchronization(ATVMPS)of different dimensional chaotic systems(DDCSs)with time delays and unknown parameters.Firstly,to estimate the unknow... This paper deals with the fixed-time adaptive time-varying matrix projective synchronization(ATVMPS)of different dimensional chaotic systems(DDCSs)with time delays and unknown parameters.Firstly,to estimate the unknown parameters,adaptive parameter updated laws are designed.Secondly,to realize the fixed-time ATVMPS of the time-delayed DDCSs,an adaptive delay-unrelated controller is designed,where time delays of chaotic systems are known or unknown.Thirdly,some simple fixed-time ATVMPS criteria are deduced,and the rigorous proof is provided by employing the inequality technique and Lyapunov theory.Furthermore,the settling time of fixed-time synchronization(Fix-TS)is obtained,which depends only on controller parameters and system parameters and is independent of the system’s initial states.Finally,simulation examples are presented to validate the theoretical analysis. 展开更多
关键词 Time-varying matrix projective synchronization(TVMPS) fixed-time control unknown parameters different dimensions time-delayed chaotic systems(TDCSs)
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A Study on the Multiple Differential Structure of Development in China^s Ethnic Areasand Exploiting the Differentiation and Collaborative Policy—On the New Form of China’s Ethnic Relations and the New System of Ethnic Policies
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作者 Xu Hongwei 《民族学刊》 2016年第3期119-120,共2页
A fter 60 years of im plem entation, the ethnic regional autonomous policy has provided basic p o litica l support for promoting the common development and prosperity of a ll ethnic groups.
关键词 the STRUCTURE of MULTIPLE DISPARITY hierarchical difference complex cooperation the DEVELOPMENT of policy.
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Trajectory Controllability of Nonlinear Integro-Differential System—An Analytical and a Numerical Estimations
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作者 Dimplekumar Chalishajar Heena Chalishajar John David 《Applied Mathematics》 2012年第11期1729-1738,共10页
A stronger concept of complete (exact) controllability which we call Trajectory Controllability is introduced in this paper. We study the Trajectory Controllability of an abstract nonlinear integro-differential system... A stronger concept of complete (exact) controllability which we call Trajectory Controllability is introduced in this paper. We study the Trajectory Controllability of an abstract nonlinear integro-differential system in the finite and infinite dimensional space setting. We will then discuss how approximations to these problems can be found computationally using finite difference methods and optimization. Examples will be presented in one, two and three dimensions. 展开更多
关键词 Trajectory CONTROLLABILITY MONOTONE Operator Theory Set VALUED Function LIPSCHITZ CONTINUITY Finite Difference Optimization
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Differentiated Production and the Differentiated Film Market System
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作者 RAO Shu-guang LI Guo-cong Wu Bi-yu 《Journal of Literature and Art Studies》 2019年第2期270-273,共4页
The relationship between the differentiated production and the differentiated film market system is paid more attention to.The paper clarifies how to explore“extended screening”and“differentiated screening”,how to... The relationship between the differentiated production and the differentiated film market system is paid more attention to.The paper clarifies how to explore“extended screening”and“differentiated screening”,how to give art films a place to survive and thrive,and how to give audiences a variety of choices.Some effective suggestions are given from three dimensions.The differentiated low and mid-budget films are tower base and trailblazer.It is also necessary to comprehensively promote the development of a differentiated film market system in order to make differentiated,localized and genre-based productions that are competitive in the market. 展开更多
关键词 DIFFERENCE production FILM MARKET system
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