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71.
陈迪 《应用数学与计算数学学报》1994,8(1):70-76
本文讨论了具有r个成败型元件串联系统可靠性的置信下限问题。研究了虚拟系统法置信下限的小样本性质,证明了,在通常情况下虚拟系统法置信下限要大于常见的L-M法置信下限.更一般地,本文证明了在成败型试验中,当成功数与试验数之比保持不变时,试验次数的增加将直接缩小成功率置信区间的长度。 相似文献
72.
HypersurfacewithConstantMainCurvatureSymmetricFunctions¥WuBaoqiang;SongHongzao(XuzhouTeachersCollege,221009)(HenanUniversity,... 相似文献
73.
Zhu Da xin 《数学年刊B辑(英文版)》1994,15(3):293-298
ACOMPLETEMETRICOFPOSITIVECURVATUREONR~nANDEXISTENCEOFCLOSEDGEODESICS¥ZHUDAXIN(DepartmentofMathematics,TianjinUniversitylTianj?.. 相似文献
74.
关于3维Minkowski空间中类空曲面的若干结果 总被引:2,自引:0,他引:2
在本文,我们证明2维黎曼流形能实现为L3中的类空极大曲面的充要条件是相应的Ricci条件成立,此外还确定了L3中其平均曲率向量h满足条件△h=λh(λ∈R)的类空曲面 相似文献
75.
Projected gradient methods for linearly constrained problems 总被引:23,自引:0,他引:23
The aim of this paper is to study the convergence properties of the gradient projection method and to apply these results
to algorithms for linearly constrained problems. The main convergence result is obtained by defining a projected gradient,
and proving that the gradient projection method forces the sequence of projected gradients to zero. A consequence of this
result is that if the gradient projection method converges to a nondegenerate point of a linearly constrained problem, then
the active and binding constraints are identified in a finite number of iterations. As an application of our theory, we develop
quadratic programming algorithms that iteratively explore a subspace defined by the active constraints. These algorithms are
able to drop and add many constraints from the active set, and can either compute an accurate minimizer by a direct method,
or an approximate minimizer by an iterative method of the conjugate gradient type. Thus, these algorithms are attractive for
large scale problems. We show that it is possible to develop a finite terminating quadratic programming algorithm without
non-degeneracy assumptions.
Work supported in part by the Applied Mathematical Sciences subprogram of the Office of Energy Research of the U.S. Department
of Energy under Contract W-31-109-Eng-38.
Work supported in part by the Applied Mathematical Sciences subprogram of the Office of Energy Research of the U.S. Department
of Energy under Contract W-31-109-Eng-38. 相似文献
76.
Error bounds for asymptotic expansions of the distribution of the MLE in a GMANOVA model 总被引:1,自引:0,他引:1
Yasunori Fujikoshi 《Annals of the Institute of Statistical Mathematics》1987,39(1):153-161
Summary In this paper we obtain asymptotic expansions for the distribution function and the density function of a linear combination
of the MLE in a GMANOVA model, and for the density function of the MLE itself. We also obtain certain error bounds for the
asymptotic expansions. 相似文献
77.
《Physics letters. A》2020,384(16):126322
Quantum key distribution (QKD) is a promising application to establish unconditional secure communications by quantum mechanics. However, its widespread application still faces a great challenge, that is, the fundamental linear key-rate constraint called Pirandola-Laurenza-Ottaviani-Banchi (PLOB) bound. Recently, twin-field QKD (TF-QKD) was proposed (Lucamarini et al., 2018 [4]), it overcomes the constraint mentioned above. However, the original TF-QKD is based on the phase-encoding strategy, which requires active alignment. In this paper, we improve the original TF-QKD with the photon orbital angular momentum (OAM), and propose a novel reference frame independent protocol to overcome the reference frame dependence. No more alignment procedure is needed, and the intrinsic misalignment errors are eliminated by utilizing the rotation-invariance of OAM photons. Besides, the security performance is also improved. 相似文献
78.
79.
The supersymmetric extension of the five-dimensional Chern–Simons gravity is studied from the Hamiltonian point of view. This model containing the Gauss–Bonnet term quadratic in the Riemann curvature is the gauge theory of the supergroup SU(2,2/1). In the first order, the theory has a polynomial structure, but the second-order leads to a nonpolynomial structure for both the Hamiltonian and the supersymmetry transformation rules of the fields. The second-order theory has the advantage that the apparent gauge degrees of freedom are unambiguously removed leaving only the physical ones. This important feature is analyzed by constructing the second-order Hamiltonian theory. The gauge invariances of the model and the generator of time evolution are found. 相似文献
80.
We give a reduction procedure to determine (locally) the surfaces with constant Gauss curvature in a three-dimensional manifold which are invariant under the action of a one-parameter subgroup of the isometry group of the ambient space. We apply this procedure to describe the invariant surfaces with constant Gauss curvature in and in . 相似文献