Browsing by Author "CHANG, YC"

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CHARACTERIZATION OF THE SHIELDING EFFECTS ON THE FREQUENCY-DEPENDENT EFFECTIVE DIELECTRIC-CONSTANT OF A WAVE-GUIDE-SHIELDED MICROSTRIP USING THE FINITE-DIFFERENCE TIME-DOMAIN METHOD
(1991-10-01)
WU, LK
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CHANG, YC
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交大名義發表
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傳播研究所
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National Chiao Tung University
The dispersion behavior of waveguide-shielded microstrip line is investigated using the finite-difference time-domain method. The result is a frequency-dependent effective dielectric constant. Structures having centered strip are examined to determine the effects of a top cover alone and the effects of two symmetrically placed sidewalls. Structures with off-centered strip are used to investigate the effects of a single sidewall alone and the combined effects of a single sidewall plus the top wall. Differences between the effects of a single sidewall alone and those of the two symmetrically placed sidewalls are identified. In addition, new results on the combined effects of the top wall plus one sidewall, which are important when considering the placement of the outermost elements of a packaged circuit, are also discussed.
ELEMENT PERTURBATION PROBLEMS OF OPTIMUM SPANNING-TREES WITH 2-PARAMETER OBJECTIVES
(1994)
CHANG, YC
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HSU, LH
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資訊科學與工程研究所
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Institute of Computer Science and Engineering
Let G = (V, E) be a graph. We associate with each edge ei E E an ordered pair of rational numbers (ni, bi). Let the weight of a spanning tree T, w(T), be defined as (Sigma(ei is an element of T) a(i))(2) + (Sigma(ei is an element of T) b(i))(2). A spanning tree T in G is called an optimum spanning tree if w(T) greater than or equal to w(T') for all spanning trees T' in G. The problem of finding the optimum spanning tree of the two-parameter objective is called MST2P. Hassin and Tamir have proposed an O(q(6)) algorithm for solving: MST2P, where q = E. Let f(G) denote the weight of the optimum spanning tree of G. The element perturbation problem of MST2P is to compute f(G - e(k)) for all e(k) is an element of E. In this paper, we present an O(q(6)) algorithm to solve the element perturbation problem of MST2P. Our algorithm can also be applied to the EPP of minimal cost/reliability ratio spanning tree problem in communication network design.
ELEMENT PERTURBATION PROBLEMS OF OPTIMUM SPANNING-TREES WITH 2-PARAMETER OBJECTIVES
(1995-01-13)
CHANG, YC
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HSU, LH
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資訊工程學系
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Department of Computer Science
Let G = (V,E) be a graph. We associate with each edge e(i) is an element of E an ordered pair of rational numbers (a(i), b(i)). Let the weight of a spanning tree T, w(T), be defined as Sigma(ei is an element of T) a(i) + Pi(ei is an element of T) b(i). A spanning tree T in G is called a w-optimum spanning tree if w(T) greater than or equal to w(T') for all spanning trees T' in G. The function w is one instance in a class of two-parameter objectives. Hassin and Tamir proposed a unified approach for solving the class of two-parameter objective optimum spanning tree problems. Let s be an objective in the class and F-s(G) denote the weight of the s-optimum spanning tree of G. The element perturbation problem of the s-optimum spanning tree is to compute F-s(G - e(k)) for all e(k) is an element of E. With Hassin and Tamir's approach, let t(s)(p, q) be the complexity of computing the s-optimum spanning tree where p = V and q = E. In this paper, we present an approach to solve the element perturbation problem of the s-optimum spanning tree in t(s)(p, q).