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91.
Interpolation norms between row and column spaces and the norm problem for elementary operators 总被引:1,自引:1,他引:0
Danko R. Joci 《Linear algebra and its applications》2009,430(11-12):2961-2974
92.
《Linear algebra and its applications》2009,430(4):1313-1327
Let C={1,2,…,m} and f be a multiplicative function such that (f∗μ)(k)>0 for every positive integer k and the Euler product converges. Let (Cf)=(f(i,j)) be the m×m matrix defined on the set C having f evaluated at the greatest common divisor (i,j) of i and j as its ij-entry. In the present paper, we first obtain the least upper bounds for the ij-entry and the absolute row sum of any row of (Cf)-1, the inverse of (Cf), in terms of ζf. Specializing these bounds for the arithmetical functions f=Nε,Jε and σε we examine the asymptotic behavior the smallest eigenvalue of each of matrices (CNε),(CJε) and (Cσε) depending on ε when m tends to infinity. We conclude our paper with a proof of a conjecture posed by Hong and Loewy [S. Hong, R. Loewy, Asymptotic behavior of eigenvalues of greatest common divisor matrices, Glasg. Math. J. 46 (2004) 551-569]. 相似文献
93.
94.
We introduce a new method to derive lower bounds on randomized and quantum communication complexity. Our method is based on factorization norms, a notion from Banach Space theory. This approach gives us access to several powerful tools from this area such as normed spaces duality and Grothendiek's inequality. This extends the arsenal of methods for deriving lower bounds in communication complexity. As we show, our method subsumes most of the previously known general approaches to lower bounds on communication complexity. Moreover, we extend all (but one) of these lower bounds to the realm of quantum communication complexity with entanglement. Our results also shed some light on the question how much communication can be saved by using entanglement. It is known that entanglement can save one of every two qubits, and examples for which this is tight are also known. It follows from our results that this bound on the saving in communication is tight almost always. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2009 相似文献
95.
In this paper, we deepen the theoretical study of the geometric structure of a balanced complex polytope (b.c.p.), which is
the generalization of a real centrally symmetric polytope to the complex space. We also propose a constructive algorithm for
the representation of its facets in terms of their associated linear functionals. The b.c.p.s are used, for example, as a
tool for the computation of the joint spectral radius of families of matrices. For the representation of real polytopes, there
exist well-known algorithms such as, for example, the Beneath–Beyond method. Our purpose is to modify and adapt this method
to the complex case by exploiting the geometric features of the b.c.p. However, due to the significant increase in the difficulty
of the problem when passing from the real to the complex case, in this paper, we confine ourselves to examine the two-dimensional
case. We also propose an algorithm for the computation of the norm the unit ball of which is a b.c.p.
This work was supported by INdAM-GNCS. 相似文献
96.
邹黎敏 《浙江大学学报(理学版)》2013,40(1):27-28
最近,对于任何的酉不变范数,KITTANEH得到了Heinz不等式的一个改进. 在这篇注记中,得到了KITTANEH结果的一个改进. 相似文献
97.
In this paper, the problem of two-dimensional fluid flow past a stationary and rotationally oscillating equilateral triangular cylinder with a variable incident angle, Reynolds number, oscillating amplitude, and oscillating frequency is numerically investigated. The computations are carried out by using a two-step Taylor-characteristic-based Galerkin (TCBG) algorithm. For the stationary cases, simulations are conducted at various incident angles of α=0.0–60.0° and Reynolds numbers of Re=50–160. For the oscillation cases, the investigations are done at various oscillating amplitudes of θmax=7.5–30.0° and oscillating frequencies of Fs/Fo=0.5–3.0 considering two different incidence angles (α=0.0°, 60.0°) and three different Reynolds numbers (Re=50, 100, 150). The results show that the influences of key parameters (incidence angle, Reynolds number, oscillating amplitude, and oscillating frequency) are significant on the flow pattern and hydrodynamic forces. For the stationary cases, at smaller angle of incidence (α≤30.0°), Reynolds number has a large impact on the position of the separation points. When α is between 30.0° and 60.0°, it was found that the separation points are located at the rear corners. From a topological point of view, the diagram of flow pattern is summarized, including two distinct patterns, namely, main separation and vortex merging. A deep analysis of the influence of Reynolds number and incidence angles on the mean pressure coefficient along the triangular cylinder surface is presented. Additionally, for the oscillating cases, the lock-on phenomenon is captured. The dominant flow patterns are 2S mode and P+S mode in lock-on region at α=0.0°. It is found at α=60.0°, however, that the flow pattern is predominantly 2S mode. Furthermore, except for the case of Fs/Fo=2.0, the mean drag decreases as the oscillating amplitude increases for each Reynolds number at α=0.0°. At α=60.0°, the minimum mean drag for Fs/Fo=1.5 is lower than that for stationary case, and occurs at θmax=15.0° (Re=100) and θmax=22.5° (Re=150), respectively. Finally, the effect of Reynolds number on a rotational oscillation cylinder is elucidated. 相似文献
98.
Hoda Bidkhori 《Journal of Combinatorial Theory, Series A》2012,119(3):765-787
In this paper we study finite Eulerian posets which are binomial, Sheffer or triangular. These important classes of posets are related to the theory of generating functions and to geometry. The results of this paper are organized as follows:
- •
- We completely determine the structure of Eulerian binomial posets and, as a conclusion, we are able to classify factorial functions of Eulerian binomial posets.
- •
- We give an almost complete classification of factorial functions of Eulerian Sheffer posets by dividing the original question into several cases.
- •
- In most cases above, we completely determine the structure of Eulerian Sheffer posets, a result stronger than just classifying factorial functions of these Eulerian Sheffer posets.
99.
《Optimization》2012,61(2):111-127
Necessary and sufficient proper efficiency conditionsand eight duality models are presented for two classes of constrained multiobjective optimal controi problemb containing albitl-ary norills and square roots of positive semidefinite quadratic forms 相似文献
100.
This study applies fuzzy sets to integrate the supply chain network of an edible vegetable oils manufacturer. The proposed fuzzy multi-objective linear programming model attempts to simultaneously minimize the total transportation costs. The first part of the total transportation costs is between suppliers and silos; and rest one is between manufacturer and warehouses. The approach incorporates all operating realities and actual flow patterns at production/distribution network with reference to demands of warehouses, capacities of tin and pet packaging lines. The model has been formulated as a multi objective linear programming model where data are modeled by triangular fuzzy numbers. Finally, the developed fuzzy model is applied for the case study, compiled the results and discussed. 相似文献