In this paper, we modify the normal Mann's iterative process to have strong convergence for a k-strictly pseudo-contractive non-self mapping in the framework of Hilbert spaces. Our results improve and extend the c...
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In this paper, we modify the normal Mann's iterative process to have strong convergence for a k-strictly pseudo-contractive non-self mapping in the framework of Hilbert spaces. Our results improve and extend the corresponding results announced by many others. (C) 2008 Elsevier Ltd. All rights reserved.
A new approach to subspace-based channel estimation for multiple-input-multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems is proposed. The proposed method exploits both the receive diversit...
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A new approach to subspace-based channel estimation for multiple-input-multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems is proposed. The proposed method exploits both the receive diversity and the statistical property of the received signal based on the iterative algorithm. To reduce the effect of residual error affecting the accuracy of the noise subspace, a measure called the Hermitian angle is introduced. In addition, the forgetting factor is used to consider a time-varying channel
This study addresses the state feedback stabilisation problem for networked control systems (NCSs) with time delays and packet losses. By introducing the concept of 'effective sensor packet', a new discrete-ti...
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This study addresses the state feedback stabilisation problem for networked control systems (NCSs) with time delays and packet losses. By introducing the concept of 'effective sensor packet', a new discrete-time switched model is formulated, and the sufficient conditions for the asymptotical stability of the closed-loop system are derived. An iterative algorithm is proposed to design the corresponding stabilising controller, and the synthesis method is also extended to the servo control case. The proposed method can be easily implemented to various applications, since it is simple and has no assumptions on the time delays model and the packet losses model. Simulation and experimental results are given to demonstrate the effectiveness of the proposed approaches.
Let K be a closed convex subset of a real Hilbert space H and assume that T-i : K -> H is a k(i)-strictly pseudo-contractive mapping for some 0 = 1. where I denotes the identity mapping on K, S : K -> H is a map...
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Let K be a closed convex subset of a real Hilbert space H and assume that T-i : K -> H is a k(i)-strictly pseudo-contractive mapping for some 0 <= k(i) < 1 such that boolean AND(N)(i=1) F(T-i) = {x is an element of K : x = T(i)x, i = 1.2 .... N) not equal empty set. Consider the following iterative algorithm in K given by {x(1) is an element of K, x(n+1) = alpha(n)gamma f(x(n)) + (1-alpha(n)A)P-K Sx(n), for all n >= 1. where I denotes the identity mapping on K, S : K -> H is a mapping defined by Sx = kx + (1 - k) Sigma(N)(i=1) eta(i)T(i)x, P-K is the metric projection of H onto K, A is a bounded linear strong positive operator on K, f is a contraction on K. It is proved that the sequence {x(n)} generated by the above iterative algorithm converges strongly to a common fixed point of {T-i}(i=1)(N), which solves a variational inequality related to the linear operator A. Our results improve and extend the results announced by [B. Halpern, Fixed points of nonexpansive maps, Bull. Amer. Math. Soc. 73 (1967) 957-961;R. Wittmann, Approximation of fixed points of nonexpansive mappings, Arch. Math. 58 (1992) 486-491;A. Moudafi, Viscosity approximation methods for fixed points problems, J. Math. Anal. Appl. 241 (2000) 46-55;G. Marino, H.K. Xu, A general iterative method for nonexpansive mappings in Hilbert spaces, J. Math. Anal. Appl. 318 (2006) 43-52] and many others. (C) 2008 Elsevier Ltd. All rights reserved.
A new system of the set-valued mixed quasi-variational-like inclusions (SSMQVLI) involving H-η-monotone operators is studied in general Banach spaces without uniform smoothness. By using the resolvent operator tech...
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A new system of the set-valued mixed quasi-variational-like inclusions (SSMQVLI) involving H-η-monotone operators is studied in general Banach spaces without uniform smoothness. By using the resolvent operator technique of H-η-monotone operators, a new iterative algorithm for finding approximate solutions to SSMQVLI is proposed. It is shown that the iterative sequences generated by the algorithm converge strongly to the exact solution of SSMQVLI under appropriate assumptions. These obtained new results have extended and improved previous results.
In this paper, we study nonlinear control of a spacecraft symmetric about its principal axis with two control torques. Using a computationally efficient H-infinity control design procedure, attitude stabilization and ...
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In this paper, we study nonlinear control of a spacecraft symmetric about its principal axis with two control torques. Using a computationally efficient H-infinity control design procedure, attitude stabilization and command tracking problems of the axisymmetric spacecraft are solved locally. The proposed nonlinear H-infinity control approach uses higher order Lyapunov functions and reformulates the difficult Hamilton-Jacobian-Isaacs inequalities as semidefinite optimization conditions. Sum-of-squares programming techniques are then applied to obtain computationally tractable solutions, from which nonlinear control laws will be constructed. The nonlinear H-infinity control designs for spacecraft are capable of exploiting the most suitable forms of Lyapunov functions for performance improvement.
In this paper, we consider and study a system of generalized variational inclusions with H-accretive operators in uniformly smooth Banach spaces. We prove the convergence of iterative algorithm for this system of gene...
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In this paper, we consider and study a system of generalized variational inclusions with H-accretive operators in uniformly smooth Banach spaces. We prove the convergence of iterative algorithm for this system of generalized variational inclusions. A new definition of H-resolvent operator as a retraction is introduced, and in support of the definition, we have constructed an example and a numerical example through Matlab programming. Some special cases are also discussed. (C) 2008 Elsevier B.V. All rights reserved.
The problem of optimal allocation of radar resources is addressed. Open-loop optimal strategies are obtained by direct optimization. The satisfaction of the Maximum Principle is verified by a noniterative process. The...
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The problem of optimal allocation of radar resources is addressed. Open-loop optimal strategies are obtained by direct optimization. The satisfaction of the Maximum Principle is verified by a noniterative process. The structure of the solutions is investigated by extensive numerical solutions and the main features of the optimal strategies are characterized.
The article focuses on a study on the development of a linear feedback guidance scheme for-low thrust Earth-orbit transfers that involve many orbital revolutions. The key concept of the proposed guidance scheme is cit...
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The article focuses on a study on the development of a linear feedback guidance scheme for-low thrust Earth-orbit transfers that involve many orbital revolutions. The key concept of the proposed guidance scheme is cited. It notes that the study used the parameterized control law in both optimization and guidance. According to the author, the scheme possesses near-optimal performance because the optimal trajectory and control can tracked by means of space vehicles.
In this paper, we introduced and study a new class of system of variational inclusions involving H(center dot,center dot)-accretive operator in Banach spaces. By using the resolvent operator technique associated with ...
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In this paper, we introduced and study a new class of system of variational inclusions involving H(center dot,center dot)-accretive operator in Banach spaces. By using the resolvent operator technique associated with H(center dot,center dot)-accretive operator, we prove the existence of the solution for the system of inclusions and develop a step-controlled iterative algorithm to approach the unique solution. (c) 2009 Elsevier Inc. All rights reserved.
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