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排序方式: 共有2698条查询结果,搜索用时 15 毫秒
991.
设D=n∏i=1p_i(n∈Z~+),p_i≡5(mod6)(i=1,2,…,n)为彼此不相同的奇素数,q≡1(mod6)为奇素数,运用Pell方程的解的性质、同余式、平方剩余、递归序列等给出了丢番图方程x~3±1=6qDy~2仅有平凡解的三个充分条件. 相似文献
992.
Mohammed El Aïdi 《Integral Transforms and Special Functions》2016,27(12):974-980
We furnish an upper bound for the moment of negative eigenvalues for a relativistic Schrödinger operator defined in a proper subspace of square-integrable functions. 相似文献
993.
994.
Presenting the structure equation of a hom-Lie algebra 𝔤, as the vanishing of the self commutator of a coderivation of some associative comultiplication, we define up to homotopy hom-Lie algebras, which yields the general hom-Lie algebra cohomology with value in a module. If the hom-Lie algebra is quadratic, using the Pinczon bracket on skew symmetric multilinear forms on 𝔤, we express this theory in the space of forms. If the hom-Lie algebra is symmetric, it is possible to associate to each module a quadratic hom-Lie algebra and describe the cohomology with value in the module. 相似文献
995.
Characterizations of Sobolev spaces associated to operators satisfying off‐diagonal estimates on balls 下载免费PDF全文
Junqiang Zhang Der‐Chen Chang Dachun Yang 《Mathematical Methods in the Applied Sciences》2017,40(8):2907-2929
Let be a metric measure space of homogeneous type and L be a one‐to‐one operator of type ω on for ω ∈[0, π /2). In this article, under the assumptions that L has a bounded H ∞ ‐functional calculus on and satisfies (p L , q L ) off‐diagonal estimates on balls, where p L ∈[1, 2) and q L ∈(2, ∞ ], the authors establish a characterization of the Sobolev space , defined via L α /2, of order α ∈(0, 2] for p ∈(p L , q L ) by means of a quadratic function S α , L . As an application, the authors show that for the degenerate elliptic operator L w : =? w ? 1div(A ?) and the Schrödinger type operator with a ∈(0, ∞ ) on the weighted Euclidean space with A being real symmetric, if n ?3, with q ∈[1, 2], , p ∈(1, ∞ ) and with , then, for all , , where the implicit equivalent positive constants are independent of f , denotes the class of Muckenhoupt weights, the reverse Hölder class, and D (L w ) and the domains of L w and , respectively. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
996.
997.
We use computational linear algebra and commutative algebra to study spaces of relations satisfied by quadrilinear operations. The relations are analogues of associativity in the sense that they are quadratic (every term involves two operations) and nonsymmetric (every term involves the identity permutation of the arguments). We focus on determining those quadratic relations whose cubic consequences have minimal or maximal rank. We approach these problems from the point of view of the theory of algebraic operads. 相似文献
998.
圆锥规划是一类重要的非对称锥优化问题.基于一个光滑函数,将圆锥规划的最优性条件转化成一个非线性方程组,然后给出求解圆锥规划的光滑牛顿法.该算法只需求解一个线性方程组和进行一次线搜索.运用欧几里得约当代数理论,证明该算法具有全局和局部二阶收敛性.最后数值结果表明算法的有效性. 相似文献
999.
Let X(t), , be a centered real-valued stationary Gaussian process with spectral density f(λ). The paper considers a question concerning asymptotic distribution of Toeplitz type quadratic functional Q
T
of the process X(t), generated by an integrable even function g(λ). Sufficient conditions in terms of f(λ) and g(λ) ensuring central limit theorems for standard normalized quadratic functionals Q
T
are obtained, extending the results of Fox and Taqqu (Prob. Theory Relat. Fields 74: 213–240, 1987), Avram (Prob. Theory
Relat. Fields 79:37–45, 1988), Giraitis and Surgailis (Prob. Theory Relat. Fields 86: 87–104, 1990), Ginovian and Sahakian
(Theory Prob. Appl. 49:612–628, 2004) for discrete time processes.
相似文献
1000.
An algorithm of sequential systems of linear equations for nonlinear optimization problems with arbitrary initial point 总被引:6,自引:0,他引:6
For current sequential quadratic programming (SQP) type algorithms, there exist two problems: (i) in order to obtain a search
direction, one must solve one or more quadratic programming subproblems per iteration, and the computation amount of this
algorithm is very large. So they are not suitable for the large-scale problems; (ii) the SQP algorithms require that the related
quadratic programming subproblems be solvable per iteration, but it is difficult to be satisfied. By using ε-active set procedure
with a special penalty function as the merit function, a new algorithm of sequential systems of linear equations for general
nonlinear optimization problems with arbitrary initial point is presented. This new algorithm only needs to solve three systems
of linear equations having the same coefficient matrix per iteration, and has global convergence and local superlinear convergence.
To some extent, the new algorithm can overcome the shortcomings of the SQP algorithms mentioned above.
Project partly supported by the National Natural Science Foundation of China and Tianyuan Foundation of China. 相似文献