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941.
H. Nakaya 《Lithuanian Mathematical Journal》2000,40(2):156-165
We study an asymptotic formula of the DirichletL-functions in the critical strip. This is an analogy of the Atkinson-type formula for DirichletL-functions.
Published in Lietuvos Matematikos Rinkinys, Vol. 40, No. 2, pp. 201–213, April–June, 2000. 相似文献
942.
邵春玉 《宁波大学学报(理工版)》1995,(3)
研究在定时有替换截尾试验下,指数模型点估计的验前参数的确定方法,讨论了验前参数的有关性质并给出了确定验前参数取值适合域的方法.最后用例子说明Bayes估计“优于”经典估计. 相似文献
943.
In this paper, a scheme of spatial perturbation is introduced into a class of excitable media, which are described
by two-dimensional partial-differential equation models. Inertial acentric force (or centripetal force), which is generated by circumgyrating the whole system vs. a right axis, is used to
disturb the system. The whole system becomes homogeneous as soon
as the spatial perturbation is imposed on even when the noise is in consideration. The principle of this scheme is confirmed based on the theory of Hopf bifurcation and numerical simulation. 相似文献
944.
A decorated lattice is suggested and the Ising model on it with three kinds
of interactions K1,
K2, and
K3 is studied. Using an equivalent transformation, the square decorated Ising lattice is transformed into a regular square Ising lattice with nearest-neighbor, next-nearest-neighbor, and four-spin interactions, and the critical fixed point is found at
K1=0.5769,
K2=-0.0671, and
K3=0.3428, which determines the critical temperature of the system. It is also found that this system and
the regular square Ising lattice, and the eight-vertex model belong to the
same universality class. 相似文献
945.
一组新氨基酸描述子用于肽定量构效关系研究 总被引:2,自引:0,他引:2
用主成分分析从20种天然氨基酸0D~3D结构信息中收集到的共1369个描述子变量得到了一组新氨基酸描述子(SZOTT), 将其用于血管紧张素转化酶抑制剂和苦味二肽结构表征并以偏最小二乘法建立定量构效关系模型, 得复相关系数RCU2分别为0.894和0.908, 留一法交互检验的复相关系数RCV2分别为0.828和0.736, 估计均方根误差RMS分别为0.331和0.195. 研究结果表明, SZOTT描述子含信息量大, 操作简便, 结构表达能力强, 有望在多肽定量构效关系研究中得到进一步推广. 相似文献
946.
PbS microcrystals with a magic‐square‐shaped structure were successfully fabricated via a simple hydrothermal route, employing (CH3COO)2Pb and Na2S2O3 as the lead and sulfur source without the assistance of any surfactant or template. S2O32‐ ions acted not only a supplier of S2‐ ions but also a coordinating reagent. The formation of the above morphology was the direct result of the coordination between thiosulfate ions and lead ions. Researches indicated that the different synthetic approach could influence the morphology of the final product. A possible formation mechanism was suggested. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
947.
“合理”QSAR模型是指在了解配体与受体相互作用模式的前提下建立定量构效关系, 这样避开了传统做法仅仅依靠样本集分子自身信息来构建预测模型的诸多弊端. 本文将此思想应用于肽/蛋白质亲和活性的研究当中, 借助于遗传算法作为虚拟受体结合靶点及相互作用模式的筛选手段得到了一种新的建模技术: 肽/蛋白质结合模式遗传虚拟筛选(genetic virtual screening of combinative mode for peptide/protein, GVSC). 该法成功解决了“合理”QSAR研究中的难题, 即大多数情况下受体结构未知而难以了解配基与之发生的结合方式. 分别使用58个血管紧张素转化酶, 18个Camel抗体蛋白cAb-lys3双位点突变残基对GVSC加以检验, 其结果表明GVSC能够较好地阐明配基与受体之间的作用机理, 并能得到优于传统方法的QSAR模型. 相似文献
948.
Three-dimensional interfacial wave theory of dendritic growth: (Ⅱ). non-axi-symmetric global wave modes and selection criterion of pattern formation 下载免费PDF全文
This paper is the continuation of part (I), which completes the
derivations of the 3D global wave modes solutions, yields the
stability criterion and, on the basis of the results obtained,
demonstrates the selection criterion of pattern formation. 相似文献
949.
In this paper we study the existence and stability of two-dimensional discrete gap
breathers in a two-dimensional diatomic face-centered square lattice
consisting of alternating light and heavy atoms, with on-site
potential and coupling potential. This study is focused on
two-dimensional breathers with their frequency in the gap that
separates the acoustic and optical bands of the phonon spectrum. We
demonstrate the possibility of the existence of two-dimensional gap
breathers by using a numerical method. Six types of two-dimensional
gap breathers are obtained, i.e., symmetric, mirror-symmetric and
asymmetric, whether the center of the breather is on a light or a
heavy atom. The difference between one-dimensional discrete gap
breathers and two-dimensional discrete gap breathers is also
discussed. We use Aubry's theory to analyze the stability of
discrete gap breathers in the two-dimensional diatomic face-centered
square lattice. 相似文献
950.
LUO Shun-Long 《理论物理通讯》2007,47(4):597-600
In classical statistics, the Fisher information is unique in the sense that it is essentially the only monotone Riemannian metric on the space of probability densities. In quantum theory, this uniqueness breaks down, and there are many natural quantum analogues of the Fisher information, among which two particular versions distinguish themselves by their intuitive and informational significance: The first has its origin in the skew information introduced by Wigner and Yanase in 1963 in the context of quantum measurement, and is defined via the square root of the density operator. The second arises from Helstrom's study of quantum detection in 1967, and is defined via the symmetric logarithmic derivative. The aim of this paper Js to compare these two versions of quantum Fisher information, and to establish two informational inequalities relating them. 相似文献