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101.
We study the effective manipulation of the Andreev bound states (ABS), zero mode Majorana fermion and Josephson current (JC) in a superconductor–normal–superconductor junction on the surface of a topological insulator in unexplored regime of parameters. It is found that the energy of the ABS changes dramatically with the phase difference between both superconductors (SCs) in a certain range of the incident angle of quasiparticles. It is shown that the velocity of Majorana fermion and the JC can be effectively tuned in a wide range of the chemical potential in the normal region (μN) and the separation width (L ) of the two SCs. In addition, we expose that the critical JC and its product with the normal resistance are, respectively, a quarter and the same to those in a graphene-based Josephson junction. The dependence of the critical JC on the chemical potential in the superconducting region is not monotonous: it increases (decreases) for small (large) μN. 相似文献
102.
This article improves results of Hamada, Helleseth and Maekawa on minihypers in projective spaces and linear codes meeting the Griesmer bound.In [10,12],it was shown that any
-minihyper, with
, where
, is the disjoint union of
points,
lines,...,
-dimensional subspaces. For q large, we improve on this result by increasing the upper bound on
non-square, to
non-square,
square,
, and (4) for
square, p prime, p<3, to
. In the case q non-square, the conclusion is the same as written above; the minihyper is the disjoint union of subspaces. When q is square however, the minihyper is either the disjoint union of subspaces, or the disjoint union of subspaces and one subgeometry
. For the coding-theoretical problem, our results classify the corresponding
codes meeting the Griesmer bound. 相似文献
103.
The Boltzmann distribution used in the steady-state analysis of the simulated annealing algorithm gives rise to several scale invariant properties. Scale invariance is first presented in the context of parallel independent processors and then extended to an abstract form based on lumping states together to form new aggregate states. These lumped or aggregate states possess all of the mathematical characteristics, forms and relationships of states (solutions) in the original problem in both first and second moments. These scale invariance properties therefore permit new ways of relating objective function values, conditional expectation values, stationary probabilities, rates of change of stationary probabilities and conditional variances. Such properties therefore provide potential applications in analysis, statistical inference and optimization. Directions for future research that take advantage of scale invariance are also discussed. 相似文献
104.
We give some sufficient conditions for proper lower semicontinuous functions on metric spaces to have error bounds (with exponents).
For a proper convex function f on a normed space X the existence of a local error bound implies that of a global error bound. If in addition X is a Banach space, then error bounds can be characterized by the subdifferential of f. In a reflexive Banach space X, we further obtain several sufficient and necessary conditions for the existence of error bounds in terms of the lower Dini
derivative of f.
Received: April 27, 2001 / Accepted: November 6, 2001?Published online April 12, 2002 相似文献
105.
106.
求解课程表问题的分支定界算法 总被引:6,自引:2,他引:6
本通过对中学排课程表问题的特征分析,给出了基于分支定界法的优化算法,数值试验表明这是解决一般编排中学课程表问题的有效算法。 相似文献
107.
本文证明了:方程x2+2m=yn,x,y,m,n∈N,gcd(x,y)=1,n>2仅有有限多组解(x,y,m,n),而且当(x,y,m,n)≠(5,3,1,3),(11,5,2,3),(7,3,5,4)时,n是适合n≡7(mod8)以及23≤n<8.5·106的奇素数,max(x,y,m)<C1;方程x2-2m=yn,x,y,m,n∈N,gcd(x,y)=1,y>1;n>2仅有有限多组解(x,y,m,n),而且这些解都满足n<2·109炉以及max(x,y,m)<C2,这里C1,C2是可有效计算的绝对常数. 相似文献
108.
设m是正整数,f(X,Y)=a0Xn+a1X(n-1)Y+...+anYn∈Z[X,Y]是Q上不可约化的叫n(n≥3)次齐次多项式。本文证明了:当gcd(m,a0)=1,n≥400且m≥10(35)时,方程|f(x,y)|=m,x,y∈z,gcd(x,y)=1,至多有6nv(m)组解(x,y),其中v(m)是同余式F(z)=f(z,1)≡0(modm)的解数。特别是当gcd(m,DF)=1时,该方程至多有6n(ω(m)+1)组解(x,y),其中DF是多项式F的判别式,ω(m)是m的不同素因数的个数. 相似文献
109.
LIWEI(李伟);CAOJINHUA(曹晋华)(InstituteofAppliedMathematics,theChineseAcademyofSciences,Beijing100080,ChinaandAsia-PacificOperatio... 相似文献
110.
LIN Zhengyan 《中国科学A辑(英文版)》2000,43(11):1154-1163
We establish the Berry-Esseen bound O(n/2) for a studentized U-statistic under the assumption of existence of the (2+)-th moment. 相似文献