摘要 :
The long-time behavior of solutions (more precisely, the existence of random pullback attractors) for an integro-differential parabolic equation of diffusion type with memory terms, more particularly with terms containing both fin...
展开
The long-time behavior of solutions (more precisely, the existence of random pullback attractors) for an integro-differential parabolic equation of diffusion type with memory terms, more particularly with terms containing both finite and infinite delays, as well as some kind of randomness, is analyzed in this paper. We impose general assumptions not ensuring uniqueness of solutions, which implies that the theory of multivalued dynamical system has to be used. Furthermore, the emphasis is put on the existence of random pullback attractors by exploiting the techniques of the theory of multivalued nonautonomous/random dynamical systems.
收起
摘要 :
This paper provides numerical evaluation and verifies spacial properties of the Linear Quadratic Coupled Delay Compensator (LQCDC) which was designed to circumvent the effects of the randomly varying distributed delays, both from ...
展开
This paper provides numerical evaluation and verifies spacial properties of the Linear Quadratic Coupled Delay Compensator (LQCDC) which was designed to circumvent the effects of the randomly varying distributed delays, both from sensor to controller and from controller to actuator, in addition to the time skew caused by mis- synchronization of sensor and controller sampling instants. With ensured numerical convergence, an oblique projection matrix is established such that its column and row spaces, respectively, constitute the control and estimation subspaces of the coupled delay compensator. Factorization of the projection matrix and a calculation method to find the steady state control gains are suggested. Two illustrative examples are demonstrated. One is used as a counter example to explore the potential instability of the linear quadratic Guassian controller that is valid only if the certainty equivalence principle holds. The other demonstrates the simulation experiment results of an aircraft flight control in longitudinal motion to verify the superiority and stability with respect to delay traffic uncertainty of the proposed LQCDC.
收起
摘要 :
The high dose/refuge strategy for delaying evolution of resistance to Bt maize [Zea mays L. (Poaceae)] relies on random mating between resistant European corn borers, Ostrinia nubilalis (Hcobner) (Lepidoptera: Crambidae), and susc...
展开
The high dose/refuge strategy for delaying evolution of resistance to Bt maize [Zea mays L. (Poaceae)] relies on random mating between resistant European corn borers, Ostrinia nubilalis (Hcobner) (Lepidoptera: Crambidae), and susceptible O. nubilalis from the refuge. However, differences in developmental rate caused by feeding on Bt maize, or infection with the microsporidium Nosema pyrausta Paillot (Microsporida: Nosematidae) may result in assortative mating. Developmental delays and mortality caused by infection with N. pyrausta and feeding on Bt maize were quantified alone and in combination in Cry1Ab-resistant and susceptible O. nubilalis. Feeding on Cry1Ab-incorporated diet significantly increased number of days from hatch to pupation and decreased survival in the resistant population. Infection with N. pyrausta increased mortality and lengthened development in both the resistant and susceptible populations. The combination of Cry1Ab-incorporated diet and infection with N. pyrausta in resistant O. nubilalis lengthened development and increased mortality to a greater extent than either factor alone. Greater larval delays of resistant O. nubilalis feeding on Bt maize could lead to temporal isolation from adults emerging from refuge maize. The resulting assortative mating would hasten the evolution of resistance. Developmental delays caused by infection with N. pyrausta may increase the likelihood of mating between resistant and infected susceptible adults emerging from refuge maize, producing infected offspring that are also more susceptible to Bt maize.
收起
摘要 :
This article describes the behavior of solutions to the delay integral equation f(x+1)=1/x∫_0~xf(x-t)f(t)dt. Here the "initial data" is an L~2 function, instead of the step function studied in [1,3]for one-dimensional random pack...
展开
This article describes the behavior of solutions to the delay integral equation f(x+1)=1/x∫_0~xf(x-t)f(t)dt. Here the "initial data" is an L~2 function, instead of the step function studied in [1,3]for one-dimensional random packing problems. We give asymptotic formulas for f, and compute a constant involved in these formulas. We compare several methods of numerical approximation for this constant.
收起
摘要 :
We investigate a random differential equation with random delay. First the nonautonomous case is considered. We show the existence and uniqueness of a solution that generates a cocycle. In particular, the existence of an attractor...
展开
We investigate a random differential equation with random delay. First the nonautonomous case is considered. We show the existence and uniqueness of a solution that generates a cocycle. In particular, the existence of an attractor is proved. Secondly we look at the random case. We pay special attention to the measurability. This allows us to prove that the solution to the random differential equation generates a random dynamical system. The existence result of the attractor can be carried over to the random case.
收起
摘要 :
In this paper, adaptive NN control is proposed for bilateral teleoperation system with dynamic uncertainties, unknown external disturbances, and unsymmetrical stochastic delays in communication channel to achieve transparency and ...
展开
In this paper, adaptive NN control is proposed for bilateral teleoperation system with dynamic uncertainties, unknown external disturbances, and unsymmetrical stochastic delays in communication channel to achieve transparency and robust stability. Compared with previous passivity-based teleoperation framework, the communication delays are unsymmetrical and stochastic. By partial feedback linearization using nominal dynamics, the nonlinear dynamics of the teleoperation system are transformed into two subsystems: local master/slave dynamics control and time-delay motion tracking. By integrating Markov jump systems and adaptive parameters updating, adaptive NN control strategy is developed. The stability of the closed-loop system and the boundedness of tracking errors are proved using Lyapunov–Krasovskii functional synthesis under specific linear matrix inequalities conditions. The proposed adaptive NN control is robust against motion disturbances, parametric uncertainties, and unsymmetrical stochastic delay, which effectiveness is validated by extensive simulation studies.
收起
摘要 :
We present a first step towards a general theory of difference and differential equationsincorporating unbounded random delays. The main technical tool relies on recent workof Lian and Lu, which generalizes the multiplicative ergo...
展开
We present a first step towards a general theory of difference and differential equationsincorporating unbounded random delays. The main technical tool relies on recent workof Lian and Lu, which generalizes the multiplicative ergodic theorem by Oseledets toBanach spaces.
收起
摘要 :
In this paper, an adaptive fuzzy control scheme is proposed for hybrid motion/force of trilateral teleoperation systems with a dual-master–single-slave configuration under stochastic time-varying delays in communication channels....
展开
In this paper, an adaptive fuzzy control scheme is proposed for hybrid motion/force of trilateral teleoperation systems with a dual-master–single-slave configuration under stochastic time-varying delays in communication channels. Different from previous works on bilateral teleoperation systems, this paper addresses dual-master trilateral control of a single holonomic-constrained robotic manipulator, where the communication delays are modeled as multiple Markov chains, and the motion/force controls are investigated under consideration of unsymmetric stochastic time-varying delays and system dynamical uncertainties. Using partial feedback linearization, the whole trilateral teleoperation system, which consists of both master and slave manipulator dynamics, is transformed into three subsystems. By integrating Markov jump systems to handle random delays, adaptive fuzzy control strategies are developed for the nonlinear teleoperators with modeling uncertainties and external disturbances by using the approximation property of the fuzzy logic systems (FLSs). It is proven that the trilateral teleoperation system is stochastically stable in mean square under specific linear matrix inequality (LMI) conditions, and all the signals of the resulting closed-loop system are uniformly bounded. The proposed scheme is validated by extensive simulations.
收起
摘要 :
It is shown that for a broad class of random binary processes, the mean of a binary process, conditioned on its zero crossings, is proportional to the derivative of the correlation function of that process. This specific mean, ref...
展开
It is shown that for a broad class of random binary processes, the mean of a binary process, conditioned on its zero crossings, is proportional to the derivative of the correlation function of that process. This specific mean, referred to as the implicit mean, can be used both to characterize a random binary waveform and to determine its delay. The proposed empirical estimator of the implicit mean is unbiased, and its variance depends on the number of selected trajectories of the waveform being processed and the correlation between those trajectories.
收起
摘要 :
This paper investigates the global asymptotic synchronization in an array of coupled neural networks with random coupling strengths, probabilistic interval time-varying coupling delays as well as unbounded distributed delays (mixe...
展开
This paper investigates the global asymptotic synchronization in an array of coupled neural networks with random coupling strengths, probabilistic interval time-varying coupling delays as well as unbounded distributed delays (mixed delays). Two important integral inequalities that include the Jensen's inequality as a special case are developed. On the basis of the developed inequalities, the properties of random variables and Lyapunov functional method, several delay-dependent sufficient synchronization criteria are derived for the considered model. The derived synchronization criteria are formulated by linear matrix inequalities (LMIs) and can be easily verified by using MATLAB LMI Toolbox. Some existing results are improved and extended by taking different values of parameters of the obtained results. Numerical simulations are finally given to demonstrate the effectiveness of the theoretical results.
收起
原文获取