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91.
V. P. Golubyatnikov 《Siberian Advances in Mathematics》2009,19(2):85-90
We describe simple sufficient conditions on tomography-type measurements of a planar set which imply convexity of this set. The cases of partial convexity and higher-dimensional sets are considered as well. 相似文献
92.
SUN Xiaowei WANG Youde 《偏微分方程(英文版)》2010,(2):203-208
We define a kind of KdV (Korteweg-de Vries) geometric flow for maps from a real line or a circle into a Kahler manifold (N,J,h) with complex structure J and metric h as the generalization of the vortex filament dynamics from a real line or a circle. By using the geometric analysis, the existence of the Cauchy problems of the KdV geometric flows will be investigated in this note. 相似文献
93.
94.
95.
《Optimization》2012,61(2):305-319
The scalarization functions were used in vector optimization for a long period. Similar functions were introduced and used in economics under the name of shortage function or in mathematical finance under the name of (convex or coherent) measures of risk. The main aim of this article is to study Lipschitz continuity properties of such functions and to give some applications for deriving necessary optimality conditions for vector optimization problems using the Mordukhovich subdifferential. 相似文献
96.
《Optimization》2012,61(6):921-933
For a rather general class of stochastic processes induced by time-stationary and by event-stationary random marked point processes, respectively, conditions are given for the almost sure finiteness of these processes and for their continuous dependence on the underlying random marked point process. 相似文献
97.
98.
Quantum correlations in a family of states comprising any mixture of a pair of arbitrary bi-qubit product pure states are studied by employing geometric discord [Phys. Rev. Lett. 105(2010) 190502] as the quantifier. First, the inherent symmetry in the family of states about local unitary transformations is revealed. Then, the analytic expression of geometric discords in the states is worked out. Some concrete discussions and analyses on the captured geometric discords are made so that their distinct features are exposed. It is found that, the more averagely the two bi-qubit product states are mixed, the bigger geometric discord the mixed state owns. Moreover, the monotonic relationships of geometric discord with different parameters are revealed. 相似文献
99.
壁板颤振的分析模型、数值求解方法和研究进展 总被引:3,自引:0,他引:3
研究壁板颤振问题需要计及大挠度变形下结构的几何非线性效应,不仅涉及气动弹性稳定性,而且关心结构的非线性颤振响应.该文回顾了飞行器壁板颤振问题的国内外研究情况,评述了在壁板颤振研究中采用的分析模型、数值求解方法以及在理论分析和试验方面的研究成果,并提出了今后壁板颤振问题的4个研究方向. 相似文献
100.
A scheme to perfectly preserve an initial qubit state in
geometric quantum computation is proposed for a single-qubit geometric
quantum gate in a nuclear magnetic resonance system. At first, by
adjusting some magnetic field parameters, one can let the dynamic
phase be proportional to the geometric phase. Then, by controlling
the azimuthal angle in the initial state, we may realize a
geometric quantum gate whose fidelity is equal to one under
cyclic evolution. This means that the quantum information is no
distortion in the process of geometric quantum computation. 相似文献