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The asymptotic relation between the first crossing point and the last exit time of Gaussian order statistics sequences
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作者 NING Zi-jun TAN Zhong-quan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第4期545-561,共17页
In this paper,we study the asymptotic relation between the first crossing point and the last exit time for Gaussian order statistics which are generated by stationary weakly and strongly dependent Gaussian sequences.I... In this paper,we study the asymptotic relation between the first crossing point and the last exit time for Gaussian order statistics which are generated by stationary weakly and strongly dependent Gaussian sequences.It is shown that the first crossing point and the last exit time are asymptotically independent and dependent for weakly and strongly dependent cases,respectively.The asymptotic relations between the first crossing point and the last exit time for stationary weakly and strongly dependent Gaussian sequences are also obtained. 展开更多
关键词 rst crossing point last exit time stationary Gaussian sequences Gaussian order statistic se-quences
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A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
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作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic order Quantity) INVENTORY time-Proportional Deterioration Two-Phased Demand
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Discussion on the feature of strong earthquake: Orderly distribution in time, space and intensity before the Western Kunlun Mountain Pass M=8.1 earthquake
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作者 张晓东 张永仙 +1 位作者 吕梅梅 余素荣 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第6期598-605,共8页
In the paper, the feature of strong earthquake orderly distribution in time, space and intensity before the Western Kunlun Mountain Pass M=8.1 earthquake is preliminarily studied. The modulation and triggering factors... In the paper, the feature of strong earthquake orderly distribution in time, space and intensity before the Western Kunlun Mountain Pass M=8.1 earthquake is preliminarily studied. The modulation and triggering factors such as the earth rotation, earth tides are analyzed. The results show that: the giant earthquakes with the magnitude more than 8 occurred about every 24 years and the earthquakes with the magnitude more than 7 about every 7 years in Chinese mainland. The Western Kunlun Mountain M=8.1 earthquake exactly occurred at the expected time; The spatial distance show approximately the same distances between each two swarms. The earth rotation, earth tide, sun tide and sun magnetic field have played a role of modulation and triggering in the intensity. At last, the condi-tions for earthquake generation and occurrence are also discussed. 展开更多
关键词 giant earthquake time space and intensity in order FEATURE
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On The Conceptions of Time and Order in Faulkner's The Sound and The Fury 被引量:1
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作者 王伟 《海外英语》 2011年第4X期206-208,共3页
The publication of the famous novel The Sound and The Fury projects the long-enduring reputation of William Faulkner as a household American writer in every nook and cranny of the world.Just in this novel,Faulkner emp... The publication of the famous novel The Sound and The Fury projects the long-enduring reputation of William Faulkner as a household American writer in every nook and cranny of the world.Just in this novel,Faulkner employs the literary device of stream of consciousness and makes a good play with time and order to his own joy,which makes it an outstanding literary feature in the novel.In this essay,the unusual conceptions of time and order in the novel are tentatively probed mainly from the following three perspectives:1) the initiative for Faulkner creating the novel as a novel against time and order.2) the disordered arrangement as an artistic device——the optimum key to delivering the story.3) the potential order underlying the seeming disorder in the novel. 展开更多
关键词 FAULKNER The SOUND and The Fury STREAM of CONSCIOUSNESS time order
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A New Kind of Two-Fold Integration Transformation in Phase Space and Its Uses in Weyl Ordering of Operators 被引量:3
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作者 FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期935-937,共3页
We propose a new two-fold integration transformation in p-q phase space∫∫^∞-∞dpdq/π e^2i(p-x)(q-y)f(p,q)≡G(x,y),which possesses some well-behaved transformation properties. We apply this transformation t... We propose a new two-fold integration transformation in p-q phase space∫∫^∞-∞dpdq/π e^2i(p-x)(q-y)f(p,q)≡G(x,y),which possesses some well-behaved transformation properties. We apply this transformation to the Weyl ordering of operators, especially those Q-P ordered and P-Q ordered operators. 展开更多
关键词 new two-fold integration transform phase space Weyl ordering of operators
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Dynamics Analysis of Fractional Order Memristive Time Delay Chaotic System and Circuit Implementation 被引量:1
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作者 Dawei Ding Hui Liu +2 位作者 Yecui Weng Xiaolei Yao Nian Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第2期65-74,共10页
The integer order memristive time delay chaotic system has attracted much attention and has been well discussed.However,the fractional order system is closer to the real system.In this paper,a nonlinear time delay cha... The integer order memristive time delay chaotic system has attracted much attention and has been well discussed.However,the fractional order system is closer to the real system.In this paper,a nonlinear time delay chaotic circuit based on fractional order memristive system was proposed.Some dynamical properties,including equilibrium points,stability,bifurcation,and Lyapunov exponent of the oscillator,were investigated in detail by theoretical analyses and simulations.Moreover,the nonlinear phenomena of coexisting bifurcation and attractor was found.The phenomenon shows that the state of this oscilator was highly sensitive to its initial value,which is called coexistent oscillation in this paper.Finally,the results of the system circuit simulation accomplished by Multisim were perfectly consistent with theoretical analyses and numerical simulation. 展开更多
关键词 FRACTIONAL order time DELAY coexisting ATTRACTORS coexisting BIFURCATION circuit simulation
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Parameter Estimation and Topology Identification of Uncertain General Fractional-order Complex Dynamical Networks with Time Delay 被引量:4
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作者 Xiaojuan Chen Jun Zhang Tiedong Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期295-303,共9页
Complex networks have attracted much attention from various fields of sciences and engineering in recent years. However, many complex networks have various uncertain information, such as unknown or uncertain system pa... Complex networks have attracted much attention from various fields of sciences and engineering in recent years. However, many complex networks have various uncertain information, such as unknown or uncertain system parameters and topological structure, which greatly affects the system dynamics. Thus, the parameter estimation and structure identification problem has theoretical and practical importance for uncertain complex dynamical networks. This paper investigates identification of unknown system parameters and network topologies in uncertain fractional-order complex network with time delays (including coupling delay and node delay). Based on the stability theorem of fractional-order differential system and the adaptive control technique, a novel and general method is proposed to address this challenge. Finally two representative examples are given to verify the effectiveness of the proposed approach. © 2014 Chinese Association of Automation. 展开更多
关键词 Adaptive control systems Complex networks Structure (composition) time delay TOPOLOGY Uncertainty analysis
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Consensus problem of second-order multi-agent systems with time-varying communication delay and switching topology 被引量:8
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作者 Chenglin Liu Fei Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期672-678,共7页
Leader-following stationary consensus problem is investigated for the second-order multi-agent systems with timevarying communication delay and switching topology. Based on Lyapunov-Krasovskii functional and Lyapunov-... Leader-following stationary consensus problem is investigated for the second-order multi-agent systems with timevarying communication delay and switching topology. Based on Lyapunov-Krasovskii functional and Lyapunov-Razumikhin functions respectively, consensus criterions in the form of linear matrix inequality (LMI) are obtained for the system with time-varying communication delays under static interconnection topology con- verging to the leader's states. Moreover, the delay-dependent consensus criterion in the form of LMI is also obtained for the system with time-invariant communication delay and switching topologies by constructing Lyapunov-Krasovskii functional. Numerical simulations present the correctness of the results. 展开更多
关键词 second-order multi-agent system time-varyingcommunication delay switching topology Lyapunov-Krasovskii Lyapunov-Razumikhin.
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Consensus of high-order continuous-time multi-agent systems with time-delays and switching topologies 被引量:1
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作者 杨谈 金跃辉 +1 位作者 王伟 史莹晶 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期164-169,共6页
Consensus problems of high-order continuous-time multi-agent systems with time-delays and switching topologies are studied. The motivation of this work is to extend second-order continuous-time multi-agent systems fro... Consensus problems of high-order continuous-time multi-agent systems with time-delays and switching topologies are studied. The motivation of this work is to extend second-order continuous-time multi-agent systems from the liter- ature. It is shown that consensus can be reached with arbitrarily bounded time-delays even though the communication topology might not have spanning trees. A numerical example is included to show the theoretical results. 展开更多
关键词 high-order multi-agent systems CONSENSUS dynamically changing topologies time-DELAYS
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EXISTENCE AND UNIQUENESS OF SOLUTIONS FOR INITIAL VALUE PROBLEMS OF SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS IN BANACH SPACES
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作者 洪世煌 胡适耕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第3期290-299,共10页
In this paper, the initial value problems of second order ordinary differential equations in Banach spaces are discussed. By using the monotone iterative technique, some existence and uniqueness theorems for solutions... In this paper, the initial value problems of second order ordinary differential equations in Banach spaces are discussed. By using the monotone iterative technique, some existence and uniqueness theorems for solutions are obtained. 展开更多
关键词 ordered Banach spaces measures of noncompactness mixed monotone operators
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Higher-order differential variational principle and differential equations of motion for mechanical systems in event space
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作者 张相武 李院院 +1 位作者 赵小侠 罗文峰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期292-298,共7页
In this paper we study the higher-order differential variational principle and differential equations of motion for mechanical systems in event space. Based on the higher-order d'Alembert principle of the system, the... In this paper we study the higher-order differential variational principle and differential equations of motion for mechanical systems in event space. Based on the higher-order d'Alembert principle of the system, the higher-order velocity energy and the higher-order acceleration energy of the system in event space are defined, the higher-order d'Alembert- Lagrange principle of the system in event space is established, and the parametric forms of Euler-Lagrange, Nielsen and Appell for this principle are given. Finally, the higher-order differential equations of motion for holonomic systems in event space are obtained. 展开更多
关键词 event space the higher-order d'Alembert-Lagrange principle the higher-order time rate of changeof force the higher-order differential equations of motion
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AN INTEGRATION METHOD WITH FITTING CUBIC SPLINE FUNCTIONS TO A NUMERICAL MODEL OF 2ND-ORDER SPACE-TIME DIFFERENTIAL REMAINDER——FOR AN IDEAL GLOBAL SIMULATION CASE WITH PRIMITIVE ATMOSPHERIC EQUATIONS
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作者 辜旭赞 张兵 王明欢 《Journal of Tropical Meteorology》 SCIE 2013年第4期388-396,共9页
In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubi... In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubic spline numerical model(Spline Model for short),which is with a quasi-Lagrangian time-split integration scheme of fitting cubic spline/bicubic surface to all physical variable fields in the atmospheric equations on spherical discrete latitude-longitude mesh.A new algorithm of"fitting cubic spline—time step integration—fitting cubic spline—……"is developed to determine their first-and2nd-order derivatives and their upstream points for time discrete integral to the governing equations in Spline Model.And the cubic spline function and its mathematical polarities are also discussed to understand the Spline Model’s mathematical foundation of numerical analysis.It is pointed out that the Spline Model has mathematical laws of"convergence"of the cubic spline functions contracting to the original functions as well as its 1st-order and 2nd-order derivatives.The"optimality"of the 2nd-order derivative of the cubic spline functions is optimal approximation to that of the original functions.In addition,a Hermite bicubic patch is equivalent to operate on a grid for a 2nd-order derivative variable field.Besides,the slopes and curvatures of a central difference are identified respectively,with a smoothing coefficient of 1/3,three-point smoothing of that of a cubic spline.Then the slopes and curvatures of a central difference are calculated from the smoothing coefficient 1/3 and three-point smoothing of that of a cubic spline,respectively.Furthermore,a global simulation case of adiabatic,non-frictional and"incompressible"model atmosphere is shown with the quasi-Lagrangian time integration by using a global Spline Model,whose initial condition comes from the NCEP reanalysis data,along with quasi-uniform latitude-longitude grids and the so-called"shallow atmosphere"Navier-Stokes primitive equations in the spherical coordinates.The Spline Model,which adopted the Navier-Stokes primitive equations and quasi-Lagrangian time-split integration scheme,provides an initial ideal case of global atmospheric circulation.In addition,considering the essentially non-linear atmospheric motions,the Spline Model could judge reasonably well simple points of any smoothed variable field according to its fitting spline curvatures that must conform to its physical interpretation. 展开更多
关键词 NUMERICAL forecast and NUMERICAL SIMULATION 2nd-order space-time differential REMAINDER NUMERICAL model cubic spline functions Navier-Stokes PRIMITIVE EQUATIONS quasi-Lagrangian time-split integration scheme global SIMULATION case
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SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:5
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作者 Harun Polat Feyzi Basar 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期254-266,共13页
Kizmaz [13] studied the difference sequence spaces ∞(A), c(A), and co(A). Several article dealt with the sets of sequences of m-th order difference of which are bounded, convergent, or convergent to zero. Alta... Kizmaz [13] studied the difference sequence spaces ∞(A), c(A), and co(A). Several article dealt with the sets of sequences of m-th order difference of which are bounded, convergent, or convergent to zero. Altay and Basar [5] and Altay, Basar, and Mursaleen [7] introduced the Euler sequence spaces e0^r, ec^r, and e∞^r, respectively. The main purpose of this article is to introduce the spaces e0^r△^(m)), ec^r△^(m)), and e∞^r△^(m))consisting of all sequences whose mth order differences are in the Euler spaces e0^r, ec^r, and e∞^r, respectively. Moreover, the authors give some topological properties and inclusion relations, and determine the α-, β-, and γ-duals of the spaces e0^r△^(m)), ec^r△^(m)), and e∞^r△^(m)), and the Schauder basis of the spaces e0^r△^(m)), ec^r△^(m)). The last section of the article is devoted to the characterization of some matrix mappings on the sequence space ec^r△^(m)). 展开更多
关键词 Difference sequence spaces of order m Schauder basis the α- β- and γ-duals matrix mappings
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CHARACTERIZATIONS OF COMPACT OPERATORS ON SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:2
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作者 Ivana Djolovi Eberhard Malkowsky 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1465-1474,共10页
In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ (... In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ ( m ) ) and e r ∞ (△ ( m ) ) and characterized some classes of matrix transformations on them. In our paper, we add a new supplementary aspect to their research by characterizing classes of compact operators on those spaces. For that purpose, the spaces are treated as the matrix domains of a triangle in the classical sequence spaces c 0 , c and ∞ . The main tool for our characterizations is the Hausdorff measure of noncompactness. 展开更多
关键词 difference sequence spaces of order m matrix transformations compact operators Hausdorff measure of noncompactness
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Existence of Positive Solutions for Higher Order Boundary Value Problem on Time Scales 被引量:2
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作者 Xie Da-peng Liu Yang +1 位作者 Sun Ming-zhe Li Yong 《Communications in Mathematical Research》 CSCD 2013年第1期1-13,共13页
In this paper, we investigate the existence of positive solutions of a class higher order boundary value problems on time scales. The class of boundary value problems educes a four-point (or three-point or two-point... In this paper, we investigate the existence of positive solutions of a class higher order boundary value problems on time scales. The class of boundary value problems educes a four-point (or three-point or two-point) boundary value problems, for which some similar results are established. Our approach relies on the Krasnosel'skii fixed point theorem. The result of this paper is new and extends previously known results. 展开更多
关键词 higher order boundary value problem positive solution SEMIPOSITONE on time scale fixed point
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The Hierarchical Order of Spaces in Arab Traditional Towns: The Case of Najd, Saudi Arabia 被引量:3
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作者 Mohammed Mashary Alnaim 《World Journal of Engineering and Technology》 2020年第3期347-366,共20页
The built environment faces many challenges in accommodating multi-cultural diversity and migrating from the suburbs, which led to different places being isolated or neglected. Sub-identities established by a specific... The built environment faces many challenges in accommodating multi-cultural diversity and migrating from the suburbs, which led to different places being isolated or neglected. Sub-identities established by a specific group of people become isolated and away from the shared identity that the built environment established for itself. We examine this issue in the Najdi </span><span style="font-family:Verdana;">built environment by examining how Najdi locals generated a holistic</span><span style="font-family:Verdana;"> hierarchical order of specs. This paper argues that the spatial order encouraged locals to develop a shared and agreed mechanism while in parallel, it gave individuals the ability to modify their places without affecting that shared holistic spatial order. 展开更多
关键词 HIERARCHY order space Built Environment Najd Urban Fabric CULTURE space Syntax
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Higher Order Moment Spectra Time-Frequency Analysis of the Geophysical Signal 被引量:1
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作者 Liu Xiang hong, Zhao Zheng yu , Xie Shu guo, Ni Bin\|bin School of Electronic Information, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第4期801-806,共6页
On the basis of an introduction of the Wigner Higher-Order spectra (WHOS) and a general class of time-frequency higher-order moment spectra, the geophysical signal was analyzed using the higher order time-frequency di... On the basis of an introduction of the Wigner Higher-Order spectra (WHOS) and a general class of time-frequency higher-order moment spectra, the geophysical signal was analyzed using the higher order time-frequency distributions (TFD). Simulation results obtained in this paper show that the higher-order TFD (Wigner Bispectrum, Wigner Trispectrum and Choi-Williams Trispectrum) have much better Time-Frequency Concentration than the second-order TFD, and the reduced interference higher-order TFD such as CWT can effectively reduce the cross-term in multicomponent signals and simultaneously obtain high time-frequency concentration. 展开更多
关键词 non stationary Wigner high order spectra time frequency higher order moment spectra cross term attenuation
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Consensus problems of first-order dynamic multi-agent systems with multiple time delays 被引量:7
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作者 纪良浩 廖晓峰 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期50-55,共6页
Consensus problems of first-order multi-agent systems with multiple time delays are investigated in this paper. We discuss three cases: 1) continuous, 2) discrete, and 3) a continuous system with a proportional pl... Consensus problems of first-order multi-agent systems with multiple time delays are investigated in this paper. We discuss three cases: 1) continuous, 2) discrete, and 3) a continuous system with a proportional plus derivative controller. In each case, the system contains simultaneous communication and input time delays. Supposing a dynamic multi-agent system with directed topology that contains a globally reachable node, the sufficient convergence condition of the system is discussed with respect to each of the three cases based on the generalized Nyquist criterion and the frequency-domain analysis approach, yielding conclusions that are either less conservative than or agree with previously published results. We know that the convergence condition of the system depends mainly on each agent’s input time delay and the adjacent weights but is independent of the communication delay between agents, whether the system is continuous or discrete. Finally, simulation examples are given to verify the theoretical analysis. 展开更多
关键词 MULTI-AGENT time delays CONSENSUS FIRST-order CONVERGENCE
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FIXED POINTS OF INCREASING OPERATORS IN ORDERED SPACE WITH APPLICATIONS 被引量:1
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作者 YANG Guang-chong(杨光崇) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第3期341-349,共9页
The minimal-maximal fixed points theorems of increasing operators are proved in ordered space and some well-known results of increasing operators and monotone operators are improved and generalized. The obtained resul... The minimal-maximal fixed points theorems of increasing operators are proved in ordered space and some well-known results of increasing operators and monotone operators are improved and generalized. The obtained results are then applied to singular nonlinear boundary problem in ordinary differential equation without any assumption of continuity, compactness, convexity and concavity. 展开更多
关键词 ordered space supremum and infimum increasing operator and fixed point singular boundary problem
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Containment Control of Fractional Order Multi-Agent Systems With Time Delays 被引量:8
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作者 Hongyong Yang Fuyong Wang Fujun Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第3期727-732,共6页
In complex environments, many distributed multiagent systems are described with the fractional-order dynamics.In this paper, containment control of fractional-order multiagent systems with multiple leader agents are s... In complex environments, many distributed multiagent systems are described with the fractional-order dynamics.In this paper, containment control of fractional-order multiagent systems with multiple leader agents are studied. Firstly,the collaborative control of fractional-order multi-agent systems(FOMAS) with multiple leaders is analyzed in a directed network without delays. Then, by using Laplace transform and frequency domain theorem, containment consensus of networked FOMAS with time delays is investigated in an undirected network, and a critical value of delays is obtained to ensure the containment consensus of FOMAS. Finally, numerical simulations are shown to verify the results. 展开更多
关键词 Containment control FRACTIONAL-order multiagent systems time delays
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