将双索斜拉梁结构分段处理，基于索、梁经典的面内振动微分方程，通过索、梁连接处的动态平衡条件，建立双索斜拉梁模型面内振动理论。应用分离变量法和边界条件对双索斜拉梁结构平面内自由振动的特征值问题进行求解并进行参数分析。同时，建立双索斜拉梁的有限元模型，有限元所得结果与本文理论研究非常吻合，证明了本文理论和方法的正确性。采用两种方法对模型进行非线性动力学研究：通过Hamilton原理采用一阶模态截断的方
Early-warning signals for impending regime shifts are highly desirable,because it is often difficult to revert a system to the previous state once a transition has occurred.Here,early-warning signals
近年来复杂网络的研究已经成为热点问题之一，尤其是对于小世界网络的研究。我们生活在各种各样的网络中，如通信网络、计算机网络、交通网络，生物网络，认知和语义网络和社会网络等。对于网络的动力学行为的研究有利于改善我们现有的网络系统，因此对于变得尤为迫切和重要。本文考虑多个相同的子网络单元组成的链状耦合的网络系统，采用分而治之的方法，分析耦合系统的邻接矩阵的特征值与其中子网络的特征值关系，并利用中心流型定
The bifurcation analysis of a simple electric power system involving two synchronous generators connected by a transmission network to an infinite-bus is carried out in this paper.In this system,the i
参与基因调控作用的蛋白质多数以聚合体的形式参与生命调节过程的,所以基因调控网络的数学模型具有高度的非线性。由于基因调控过程是由一系列生化反应来实现的,它在本质上又具有随机性。已有研究表明,mRNA和蛋白质等物质均以阵发性的方式产生,这种产生方式呈现出了"重尾"的分布特性,即基因片段会瞬间开始高频率地进行转录,随后又快速地衰减。注意到含有跳跃成份的Levy扩散能呈现多项式衰减的"重尾"分布特征,因而
Isoxazoles have a wide variety of bioactivities,and widely applied in the field of medicines and pesticides.Isoxazoles are an important class of N-heterocycles.
2H-azirines skeleton is a key heterocyclic motif that is responsible for a broad spectrum of biological and pharmacological activities,and has become a key substructure in drug design.
Indoles derivatives have received much attention as building blocks for the synthesis of many natural products and other biological active compounds.Allene is a class of unsaturated compound with cumu
In the synthesis of 2-(4-fluorophenyl)thiophene(1),the 1-bromo-4-fluorobenzene and 2-bromothiophene was used as starting material,the highest yield was obtained when reaction time was 8h at 20℃ ; 2 an
The study on Organic Electroluminescence Devices(OELDs)have become one of the fascinating fields recently.Compared with Inorganic Electroluminescence Devices,OELDs possess excellent features,such as h