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81.
82.
本文证明了赋范线性空间中闭弱拟凸集必为凸集,并指出郭元明的”弱拟凸集的一些性质及其应用”、“广义凸集的联合逼近特性”两文中的主要结论实质上是已知的结果. 相似文献
83.
研究了拟Fourier-Jacobi级数逐项求导后所得的导级教,给出了一个等价收敛定理. 相似文献
84.
The problem of nonlinear optimization is encountered while fitting the observed response of certain radiation detectors. In
this paper the development of an optimizing technique based on quasi random search is described. The performance of this technique
is compared with other existing methods of gradient search and linear Taylor differential correction technique in the case
of fitting the photopeak responses of Nal(Tl) detectors. Our results are favourable especially when the observed data are
associated with poor statistics. 相似文献
85.
CHEN Xia & CHEN Xiru School of Mathematics Statistics Wuhan University Wuhan China Graduate School Chinese Academy of Science Beijing China 《中国科学A辑(英文版)》2005,48(6):829-846
This paper gives a thorough theoretical treatment on the adaptive quasi-likelihood estimate of the parameters in the generalized linear models. The unknown covariance matrix of the response variable is estimated by the sample. It is shown that the adaptive estimator defined in this paper is asymptotically most efficient in the sense that it is asymptotic normal, and the covariance matrix of the limit distribution coincides with the one for the quasi-likelihood estimator for the case that the covariance matrix of the response variable is completely known. 相似文献
86.
87.
Yusuke Hamabe Sungbong Jung Hikotaro Suzuki Naoto Koizumi Muneyoshi Yamada 《Journal of synchrotron radiation》2010,17(4):530-539
Ni species on the spent NiMo catalyst from ultra‐deep hydrodesulfurization of gas oil in a commercial plant were studied by Ni K‐edge EXAFS and TEM measurement without contact of the catalysts with air. The Ni–Mo coordination shell related to the Ni–Mo–S phase was observed in the spent catalyst by quasi in situ Ni K‐edge EXAFS measurement with a newly constructed high‐pressure chamber. The coordination number of this shell was almost identical to that obtained by in situ Ni K‐edge EXAFS measurement of the fresh catalyst sulfided at 1.1 MPa. On the other hand, large agglomerates of Ni3S2 were observed only in the spent catalyst by quasi in situ TEM/EDX measurement. MoS2‐like slabs were sintered slightly on the spent catalyst, where they were destacked to form monolayer slabs. These results suggest that the Ni–Mo–S phase is preserved on the spent catalyst and Ni3S2 agglomerates are formed by sintering of Ni3S2 species originally present on the fresh catalyst. 相似文献
88.
《Journal of Graph Theory》2018,88(1):192-210
A tournament is called locally transitive if the outneighborhood and the inneighborhood of every vertex are transitive. Equivalently, a tournament is locally transitive if it avoids the tournaments W4 and L4, which are the only tournaments up to isomorphism on four vertices containing a unique 3‐cycle. On the other hand, a sequence of tournaments with is called almost balanced if all but vertices of have outdegree . In the same spirit of quasi‐random properties, we present several characterizations of tournament sequences that are both almost balanced and asymptotically locally transitive in the sense that the density of W4 and L4 in goes to zero as n goes to infinity. 相似文献
89.
90.
We investigate some geometric properties of level sets of the solutions of parabolic problems in convex rings. We introduce the notion of parabolic quasi‐concavity, which involves time and space jointly and is a stronger property than the spatial quasi‐concavity, and study the convexity of superlevel sets of the solutions (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献