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91.
函数连接型网络应用于维生素B族四组分同时测定 总被引:6,自引:0,他引:6
报道了函数连接型网络(FLN)用于维生素B族四组分同时测定。采用相关系数和标准偏差从原始紫外光谱数据中挑选11个波长点供网络处理。在函数连接型网络中,非线性输入模式得到了增强,并使用了推广的δ学习规则。预测结果极行,其相关系数和标准偏差分别为0.99904和0.26885。 相似文献
92.
Thecalcualtionof〈zk1,zk2,…,zkn〉LofthispaperwillbeintermoftheKauffmanbracket-polynomial[1,2,3].TheKauffmanbracketpolynomialofaplanardiagramofanunorientedlinkisanelement〈D〉∈Z[A,A-1]definedbythefollowingprocess.AstateofDisdefinedtobeamapsfromthecrossing… 相似文献
93.
Darryl McCullough 《Proceedings of the American Mathematical Society》2003,131(7):2247-2253
Fix a free, orientation-preserving action of a finite group on a -dimensional handlebody . Whenever acts freely preserving orientation on a connected -manifold , there is a -equivariant imbedding of into . There are choices of closed and Seifert-fibered for which the image of is a handlebody of a Heegaard splitting of . Provided that the genus of is at least , there are similar choices with closed and hyperbolic.
94.
François Jaeger 《Journal of Algebraic Combinatorics》1995,4(2):103-144
Motivated by the construction of invariants of links in 3-space, we study spin models on graphs for which all edge weights (considered as matrices) belong to the Bose-Mesner algebra of some association scheme. We show that for series-parallel graphs the computation of the partition function can be performed by using series-parallel reductions of the graph appropriately coupled with operations in the Bose-Mesner algebra. Then we extend this approach to all plane graphs by introducing star-triangle transformations and restricting our attention to a special class of Bose-Mesner algebras which we call exactly triply regular. We also introduce the following two properties for Bose-Mesner algebras. The planar duality property (defined in the self-dual case) expresses the partition function for any plane graph in terms of the partition function for its dual graph, and the planar reversibility property asserts that the partition function for any plane graph is equal to the partition function for the oppositely oriented graph. Both properties hold for any Bose-Mesner algebra if one considers only series-parallel graphs instead of arbitrary plane graphs. We relate these notions to spin models for link invariants, and among other results we show that the Abelian group Bose-Mesner algebras have the planar duality property and that for self-dual Bose-Mesner algebras, planar duality implies planar reversibility. We also prove that for exactly triply regular Bose-Mesner algebras, to check one of the above properties it is sufficient to check it on the complete graph on four vertices. A number of applications, examples and open problems are discussed. 相似文献
95.
博客(Blog)网站作为近年来新型的网络媒体得到越来越多的个人和企业的关注,因此针对Blog数据设计了相应的数据分析系统.并介绍了Blog数据分析与传统Web挖掘的区别和联系,阐明研究了Blog数据的必要性,其次详细分析了本系统的主要功能模块及其实现方法,最后采集中国博客网的数据对本系统进行验证,实验结果显示本系统是可行且有效的. 相似文献
96.
我们选择了由40个CH基团组成的环形聚乙炔链作为分子桥,基于Landauer-Buttiker理论,利用求解散射波函数的方法,研究了这种环状聚乙炔分子桥与金属多端连接的电导随能量的变化关系.结果表明,在给定入射端的条件下,电导在正负能量上是对称的,当各个端口满足旋转对称性时,相对于入射端对称的两个出射端的电导相同.当分子桥耦合较弱时,电导对能量的变化相当敏感. 相似文献
97.
周治修 《浙江大学学报(理学版)》2005,32(1):21-24,29
T.Kanenobu研究了K(a,b)与K(p1,p2,…,pn)的多项式不变量的基本结构,此文讨论了更一般的K(A,B)与K(P1,P2,…,Pn)的多项式不变量的性质.所采用的工具是skein理论,主要结果为命题5~9.其中关于K(A,B)的结论可以推广到一族Km(A,B)(m∈Z). 相似文献
98.
V. O. Manturov 《Acta Appl Math》2002,74(3):293-336
In this paper, we introduce a way of encoding links (long links). This ways leads to a combinatorial representation of links by words in a given finite alphabet. We prove that the link semigroup is isomorphic to some algebraically defined semigroup with a simple system of relations. Thus, knot theory is represented as a bracket calculus: the link recognition problem is reduced to a recognition problem in this semigroup. 相似文献
99.
100.
The advantages of a radio-frequency (r.f.) method in comparison with conventional transport measurements for characterization of superconducting weak links are discussed. In particular it is pointed out, that (i) the current–phase relationship (CPR) can be deduced from r.f. measurements of the phase-biased weak link without any fitting parameters and (ii) the supercurrent is measurable even if the Josephson coupling energy is considerably smaller than the thermal energy. Examples of the CPR for several configurations of Josephson junctions are shown. 相似文献