The direct (DIviding RECTangles) algorithm JONESJOTi, a variant ofLipschitzian methods for bound constrained global optimization, hasbeen applied to the optimal transmitter placement for indoor wirelesssystems. Power ...
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The direct (DIviding RECTangles) algorithm JONESJOTi, a variant of
Lipschitzian methods for bound constrained global optimization, has
been applied to the optimal transmitter placement for indoor wireless
systems. Power coverage and BER (bit error rate) are considered as
two criteria for optimizing locations of a specified number of
transmitters across the feasible region of the design space. The
performance of a direct implementation in such applications depends
on the characteristics of the objective function, the problem
dimension, and the desired solution accuracy. Implementations with
static data structures often fail in practice because of unpredictable
memory requirements. This is especially critical in $S^4W$
(Site-Specific System Simulator for Wireless communication systems),
where the direct optimization is just one small component connected
to a parallel 3D propagation ray tracing modeler running on a 200-node
Beowulf cluster of Linux workstations, and surrogate functions for a
WCDMA (wideband code division multiple access) simulator are also
used to estimate the channel performance. Any component failure of this
large computation would abort the entire design process. To make the
direct global optimization algorithm efficient and robust, a set of
dynamic data structures is proposed here to balance the memory
requirements with execution time, while simultaneously adapting to
arbitrary problem size. The focus is on design issues of the dynamic data
structures, related memory management strategies, and application issues
of the direct algorithm to the transmitter placement optimization for
wireless communication systems. Results for two indoor systems
are presented to demonstrate the effectiveness of the present work.
In this paper, a new direct algorithm for solving linear complementarity problem with Z-matrix is proposed. The algorithm exhibits either a solution or its nonexistence after at most n steps (where n is the dimension ...
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In this paper, a new direct algorithm for solving linear complementarity problem with Z-matrix is proposed. The algorithm exhibits either a solution or its nonexistence after at most n steps (where n is the dimension of the problem) and the computational complexity is at most 1/3n^2+O(n^2)
An algorithm for the computation of the continued fraction expansions of numbers which are zeros of differentiable functions is given. The method is direct in the sense that it requires function evaluations at appropr...
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An algorithm for the computation of the continued fraction expansions of numbers which are zeros of differentiable functions is given. The method is direct in the sense that it requires function evaluations at appropriate steps, rather than the value of the number as input in order to deliver the expansion. Statistical data on the first 10000 partial quotients for various real numbers are also given.
First, the concepts of fuzzy valuation convex (or concave) function and fuzzy convex-geometric-programming problem are based on a fuzzy valuation set in this paper. Secondly, fuzzy posynomial geometric programming and...
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First, the concepts of fuzzy valuation convex (or concave) function and fuzzy convex-geometric-programming problem are based on a fuzzy valuation set in this paper. Secondly, fuzzy posynomial geometric programming and its dual-form properties concerned are discussed by means of a fuzzy geometric inequality and of a fuzzy dual theory. Lastly, direct and dual algorithms of fuzzy posynomial geometric programming are respectively deduced by the aid of a fuzzy fixed-point theorem and the notion of α, β-cut.
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