The envelope constrained (EC) filtering problem is concerned with the design of a time-invariant filter to process a given input pulse such that the output waveform is guaranteed to lie within a prescribed output mask...
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The envelope constrained (EC) filtering problem is concerned with the design of a time-invariant filter to process a given input pulse such that the output waveform is guaranteed to lie within a prescribed output mask. Using the orthonormal Laguerre functions the EC filtering problem can be posed as a quadratic programming (QP) problem with affine inequality constraints. An iterative algorithm for solving this QP problem is proposed. We also show that for the EC filtering problem, filters based on Laguerre functions offer a more robust and low-order alternative to finite impulse response (FIR) filters. A numerical example, concerned with the design of an equalization filter for a digital transmission channel, is presented to illustrate the effectiveness of the iterative algorithm and the Laguerre filter.
The parallelization of iterative algorithms is an important issue for efficient solution of large numerical problems. Several theoretical results concerning sufficient conditions for. and speed of convergence of paral...
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The parallelization of iterative algorithms is an important issue for efficient solution of large numerical problems. Several theoretical results concerning sufficient conditions for. and speed of convergence of parallel iterative algorithms are available. However, those results usually do not take into account the processor workloads and network communications at the application level. The approach in this paper develops a Markov chain based on random variables which describe aspects of the multiuser, distributed-memory environment and the phases of the algorithm. The performance characterization addresses stochastic characteristics of the algorithmic execution time such as mean values and standard deviations. We present simulation results as well as experimental results over different time periods. The results provide information about the impact of distributed environment and implementation style on long-run expected execution time characteristics. (C) Academic Press.
Due to the 'soft-field' nature of electrical capacitance tomography, it is necessary to employ an iterative approach for image reconstruction in order to obtain good-quality images. In an iterative algorithm i...
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Due to the 'soft-field' nature of electrical capacitance tomography, it is necessary to employ an iterative approach for image reconstruction in order to obtain good-quality images. In an iterative algorithm it is important to determine the gain factor, i.e., the step length approaching the converging point, because it may either cause divergence or slow down the iterative process. Usually the step length is fixed. In this communication, a method to determine the optimal step length is derived for an iterative algorithm. The efficiency of the method has been demonstrated experimentally.
Let K be a closed convex subset of a Banach space X. We consider complete metric spaces of self-mappings of K which are nonexpansive with respect to a convex function on X. We prove that the iterates of a generic oper...
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Let K be a closed convex subset of a Banach space X. We consider complete metric spaces of self-mappings of K which are nonexpansive with respect to a convex function on X. We prove that the iterates of a generic operator in these spaces converge strongly. In some cases the limits do not depend on the initial points and are the unique fixed point of the operator.
In this paper, we introduce and study a new class of generalized implicit quasivariational inclusions with fuzzy set-valued mappings. A existence theorem of solutions is proved without compactness assumptions. A new i...
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In this paper, we introduce and study a new class of generalized implicit quasivariational inclusions with fuzzy set-valued mappings. A existence theorem of solutions is proved without compactness assumptions. A new iterative algorithm is suggested and analyzed. The convergence of iterative sequence generated by the new algorithm is also given. As special cases, some known results are also discussed. (C) 1999 Elsevier Science Ltd. All rights reserved.
In this paper, by applying the auxiliary variational principle technique, some existence theorems of solutions for a class of mixed implicit quasi-variational inequalities with fuzzy mappings are proved in Hilbert spa...
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In this paper, by applying the auxiliary variational principle technique, some existence theorems of solutions for a class of mixed implicit quasi-variational inequalities with fuzzy mappings are proved in Hilbert spaces. A novel and innovative iterative algorithm to compute approximate solutions is suggested and analyzed. The convergence criteria is also given. As special cases of these results, the open problem put forward by Noor is answered positively. Our results are new and generalize a number of known results to mixed implicity quasi-variational inequalities with fuzzy mappings. (C) 1999 Elsevier Science Ltd. All rights reserved.
The determination of lower bound limit load of 3-D structures is by no means an easy task, especially for complex configurations and loading systems. In our previous work, a numerical method of upper bound limit analy...
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The determination of lower bound limit load of 3-D structures is by no means an easy task, especially for complex configurations and loading systems. In our previous work, a numerical method of upper bound limit analysis for 3-D structures with multi-loading systems was proposed. This method combines FEM and mathematical programming technique in an iterative procedure. In the present article, on the basis of the nature of the iterative procedure for upper bound limit analysis, the statically admissible stress fields, which satisfies the equilibrium equation and boundary conditions, are constructed using some intermediate variables obtained by upper bound limit analysis procedure. Moreover, a mathematical programming formulation is set up for the static limit analysis of 3-D structures under multi-loading systems and a direct iterative algorithm used to determine the lower bound limit load multiplier is proposed, which depends on the static theorem of plasticity. The numerical examples are given to demonstrate the applicability of the procedure. (C) 1999 Elsevier Science Ltd. All rights reserved.
In this paper, a new class of generalized nonlinear implicit quasivariational inclusions involving a set-valued maximal monotone wrapping are studied. A existence theorem of solutions for this class of generalized non...
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In this paper, a new class of generalized nonlinear implicit quasivariational inclusions involving a set-valued maximal monotone wrapping are studied. A existence theorem of solutions for this class of generalized nonlinear implicit quasivariational inclusions is Proved without compactness assumptions. A new iterative algorithm for finding approximate solutions of the generalized nonlinear implicit quasivariational inclusions is suggested and analysed and the convergence of iterative sequence generated by the new algorithm is also given, As special cases, some known results in this field are also discussed.
In this paper, by applying the auxiliary variational principle technique, an existence theorem of solutions for a new class of generalized mixed variational inequalities is proved in Hilbert spaces. A novel and innova...
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In this paper, by applying the auxiliary variational principle technique, an existence theorem of solutions for a new class of generalized mixed variational inequalities is proved in Hilbert spaces. A novel and innovative iterative algorithm to compute approximate solutions is suggested and analyzed. The convergence criteria and error estimates are also given. These results of existence, algorithm, and convergence are new and generalize some corresponding results involving single-valued mappings in recent literatures. (C) 1999 Elsevier Science Ltd. All rights reserved.
作者：
Yang, WQLiu, SUniv Manchester
Inst Sci & Technol Dept Elect Engn & Elect Proc Tomog Grp Manchester M60 1QD Lancs England Chinese Acad Sci
Inst Engn Thermophys Beijing 100080 Peoples R China
Electrical capacitance tomography (ECT) with circular sensors has previously been investigated. For some industrial applications such as circulating fluidised beds, square sensors are required. Research into this spec...
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Electrical capacitance tomography (ECT) with circular sensors has previously been investigated. For some industrial applications such as circulating fluidised beds, square sensors are required. Research into this specific area has been carried out for the first time. To generate sensitivity maps, the Laplace equation is solved using a finite difference method. Both the linear back-projection algorithm and an iterative algorithm have been implemented for image reconstruction. Experimental results are promising.
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