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61.
Takanori Ide Hiroshi Isozaki Susumu Nakata Samuli Siltanen Gunther Uhlmann 《纯数学与应用数学通讯》2007,60(10):1415-1442
Let a physical body Ω in ?2 or ?3 be given. Assume that the electric conductivity distribution inside Ω consists of conductive inclusions in a known smooth background. Further, assume that a subset Γ ? ?Ω is available for boundary measurements. It is proved using hyperbolic geometry that certain information about the location of the inclusions can be exactly recovered from static electric measurements on Γ. More precisely: given a ball B with center outside the convex hull of Ω and satisfying (B? ∩ ?Ω) ? Γ, boundary measurements on Γ with explicitly given Dirichlet data are enough to determine whether B intersects the inclusion. An approximate detection algorithm is introduced based on the theory. Numerical experiments in dimension two with simulated noisy data suggest that the algorithm finds the inclusion‐free domain near Γ and is robust against measurement noise. © 2007 Wiley Periodicals, Inc. 相似文献
62.
In this paper we investigate the acute triangulations of flat Mobius strips. We find out that we can always triangulate a
flat Mobius strip with at most nine acute triangles, and sometimes (but not always) that many triangles are really needed. 相似文献
63.
64.
65.
《Physica A》2006,369(2):266-274
The Percus–Yevick equation is solved numerically for hard disks on a sphere. The effect of curvature of the hosting surface is calculated, and an empirical correction to the equation of state is proposed. 相似文献
66.
《European Journal of Operational Research》2006,174(2):887-904
Consider a two-stage production system with a significant setup time at the upstream station. A threshold production control rule is used at the upstream station, with an objective of minimizing the work-in-process level while maintaining a required busy probability at the downstream station. To characterize the system performance under this rule, a Markov model is constructed and from which the analytical performance measures are obtained. The objective function for the decision rule is found to have good analytical properties and numerical optimization can thus be performed using a simple algorithm. 相似文献
67.
We consider the classical problem of searching for a heavier coin in a set of n coins, n-1 of which have the same weight. The weighing device is b-balance which is the generalization of two-arms balance. The minimum numbers of weighings are determined exactly for worst-case sequential algorithm, average-case sequential algorithm, worst-case predetermined algorithm, average-case predetermined algorithm.We also investigate the above search model with additional constraint: each weighing is only allowed to use the coins that are still in doubt. We present a worst-case optimal sequential algorithm and an average-case optimal sequential algorithm requiring the minimum numbers of weighings. 相似文献
68.
We describe the fractal structure of expanding meromorphic maps of the form , where H and Q are rational functions whose most transparent examples are among the functions of the form with . In particular we show that depending upon whether the Hausdorff dimension of the Julia set is greater or less than 1, the
finite non-zero geometric measure is provided by the Hausdorff or packing measure. In order to describe this fractal structure
we introduce and explore in detail Walters expanding conformal maps and jump-like conformal maps.
Received: 3 May 2001 / Published online: 5 September 2002 相似文献
69.
In this paper, we give a necessary and sufficient solvable condition for diagonal cubic equation with prime variable in arithmetic progressions and the outline of the proof. 相似文献
70.
This paper discusses a kind of optimization problem with linear complementarity constraints, and presents a sequential quadratic
programming (SQP) algorithm for solving a stationary point of the problem. The algorithm is a modification of the SQP algorithm
proposed by Fukushima et al. [Computational Optimization and Applications, 10 (1998),
5-34], and is based on a reformulation of complementarity condition as a system of linear equations. At each iteration,
one quadratic programming and one system of equations needs to be solved, and a curve search is used to yield the step size.
Under some appropriate assumptions, including the lower-level strict complementarity, but without the upper-level strict
complementarity for the inequality constraints, the algorithm is proved to possess strong convergence and superlinear convergence.
Some preliminary numerical results are reported. 相似文献