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31.
Device-to-Device(D2D) communication has been proposed as a promising implementation of green communication to benefit the existed cellular network.In order to limit cross-tier interference while explore the gain of short-range communication,we devise a series of distributed power control(DPC) schemes for energy conservation(EC)and enhancement of radio resource utilization in the hybrid system.Firstly,a constrained opportunistic power control model is built up to take advantage of the interference avoidance methodology in the presence of service requirement and power constraint.Then,biasing scheme and admission control are added to evade ineffective power consumption and maintain the feasibility of the system.Upon feasibility,a non-cooperative game is further formulated to exploit the profit in EC with minor influence on spectral efficiency(SE).The convergence of the DPC schemes is validated and their performance is confirmed via simulation results. 相似文献
32.
We generalize Axel Thue’s familiar definition of overlaps in words, and observe that there are no infinite words avoiding split occurrences of these generalized overlaps. We give estimates for the length of the longest finite word that avoids split overlaps. Along the way we prove a useful theorem about repeated disjoint occurrences in words — an interesting natural variation on the classical de Bruijn sequences. 相似文献
33.
This paper deals with the Lipschitz regularity of minimizers for a class of variational obstacle problems with possible occurrence of the Lavrentiev phenomenon. In order to overcome this problem, the availment of the notions of relaxed functional and Lavrentiev gap is needed. The main tool used here is a crucial Lemma which reveals to be needed because it allows us to move from the variational obstacle problem to the relaxed-functional-related one. This is fundamental in order to find the solutions’ regularity that we intended to study. We assume the same Sobolev regularity both for the gradient of the obstacle and for the coefficients. 相似文献
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Vidya Venkateswaran 《Discrete Mathematics》2007,307(21):2508-2513
We say the pair of patterns (σ,τ) is multiset Wilf equivalent if, for any multiset M, the number of permutations of M that avoid σ is equal to the number of permutations of M that avoid τ. In this paper, we find a large new class of multiset Wilf equivalent pairs, namely, the pair (σn-2(n-1)n, σn-2n(n-1)), for n?3 and σn-2 a permutation of {1x1,2x2,…,(n-2)xn-2}. It is the most general multiset Wilf equivalence result to date. 相似文献
35.
Håkan Hedenmalm 《Journal of Mathematical Analysis and Applications》2006,314(1):345-362
In practical work with American put options, it is important to be able to know when to exercise the option, and when not to do so. In computer simulation based on the standard theory of geometric Brownian motion for simulating stock price movements, this problem is fairly easy to handle for options with a short lifespan, by analyzing binomial trees. It is considerably more challenging to make the decision for American put options with long lifespan. In order to provide a satisfactory analysis, we look at the corresponding free boundary problem, and show that the free boundary—which is the curve that separates the two decisions, to exercise or not to—has an asymptotic expansion, where the coefficient of the main term is expressed as an integral in terms of the free boundary. This raises the perspective that one could use numerical simulation to approximate the integral and thus get an effective way to make correct decisions for long life options. 相似文献
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Noah Arbesfeld 《Discrete Mathematics》2013,313(22):2614-2625
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We study the homogenization of p-Laplacian with obstacles in perforated domain, where the holes are periodically distributed and have random size. And we assume that the p-capacity of each hole is stationary ergodic. 相似文献