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51.
刘理蔚 《高校应用数学学报(A辑)》1995,(1)
本文在实Banach空间的锥上证明了集值映射的随机逼近定理.作为应用,讨论了几个随机的不动点定理.我们的工作推广了Lin,Sehgal和Singh的结果. 相似文献
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The evidence for the existence of a chemical mechanism in surface‐enhanced resonance Raman scattering (SERRS) of rhodamine 6G (R6G) adsorbed on colloidal silver excited at 1064 nm is reported on the basis of experimental and theoretical analyses. A weak absorption peak at around 1060 nm for R6G‐functionalized silver nanoparticles was observed, which is not present in the individual spectra of R6G or silver nanoparticles. Theoretically, the charge difference density reveals that this weak absorption is a metal‐to‐molecule charge transfer excited state. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
55.
For b ∈ Lip(?n); the Calderón commutator with variable kernel is defined by In this paper, we establish the L2(?n) boundedness for [b, T1] with Ω(x, z′) ∈ L∞(?n)-Lq(Sn-1) (q > 2(n-1)=n) satisfying certain cancellation conditions. Moreover, the exponent q > 2(n-1)/n is optimal. Our main result improves a previous result of Calderón.
相似文献
$$[b,{T_1}]f(x) = p.v.\int_{{R n}} {\frac{{\Omega (x,x - y)}}{{|x - y{| {n + 1}}}}(b(x) - b(y))f(y)dy} $$
56.
Jianzhong Zhang Liwei Zhang Xiantao Xiao 《Mathematical Methods of Operations Research》2010,72(3):379-404
We consider an inverse quadratic programming (QP) problem in which the parameters in both the objective function and the constraint
set of a given QP problem need to be adjusted as little as possible so that a known feasible solution becomes the optimal
one. We formulate this problem as a linear complementarity constrained minimization problem with a positive semidefinite cone
constraint. With the help of duality theory, we reformulate this problem as a linear complementarity constrained semismoothly
differentiable (SC1) optimization problem with fewer variables than the original one. We propose a perturbation approach to solve the reformulated
problem and demonstrate its global convergence. An inexact Newton method is constructed to solve the perturbed problem and
its global convergence and local quadratic convergence rate are shown. As the objective function of the problem is a SC1 function involving the projection operator onto the cone of positively semi-definite symmetric matrices, the analysis requires
an implicit function theorem for semismooth functions as well as properties of the projection operator in the symmetric-matrix
space. Since an approximate proximal point is required in the inexact Newton method, we also give a Newton method to obtain
it. Finally we report our numerical results showing that the proposed approach is quite effective. 相似文献
57.
采用激发波长800 nm、脉宽50 fs、重复频率1 kHz的Ti:sapphire放大飞秒激光器作为激发光源,利用开孔Z扫描技术研究了不同粒径的CdTe:Mn量子点的非线性吸收性质。理论计算结果表明,同一生长时间CdTe:Mn量子点的双光子吸收系数是CdTe量子点的1.1倍,其双光子吸收系数随量子点尺寸的减小而增大,这是由于CdTe:Mn量子点非线性吸收属于反饱和吸收,掺杂了Mn元素,减小了表面缺陷浓度,表明掺杂量子点具有很好的双光子吸收现象。 相似文献
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The (parabolic) second-order directional derivatives of singular values of matrices and symmetric matrix-valued functions induced by real-valued functions play important roles in studying second-order optimality conditions for different types of matrix cone optimization problems. We propose a direct way to derive the formula for the second-order directional derivative of any eigenvalue of a symmetric matrix in Torki (Nonlinear Anal 46:1133–1150 2001), from which a formula for the second-order directional derivative of any singular value of a matrix is established. We demonstrate a formula for the second-order directional derivative of the symmetric matrix-valued function. As applications, the second-order derivative for the projection operator over the SDP cone is derived and used to get the second-order tangent set of the SDP cone in Bonnans and Shapiro (2000), and the tangent cone and the second-order tangent set of the epigraph of the nuclear norm are given as well. 相似文献
60.
Liwei CHEN 《物理化学学报》2019,35(12):1299-1300
<正>随着人类对能源需求的持续提高,太阳能、风能等可再生能源的开发和利用备受关注。可再生能源发电的规模化发展需要与之相匹配的大规模、高效能量存储技术。液流电池是有潜力的大型电化学储能技术之一,具有储能规模大、循环寿命长、安全性高等优势1,2。发展更高储能密度、更低成本、可商业化应用的液流电池技术是实现国家能源安全和可持续发展的重大需求。液流电池的 相似文献