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51.
Suspension bridges are widely used as engineering structures to across long spans and give rise to the usage of domains under the bridge. In the finite element analyses of suspension bridges, it is assumed that the structure is built and loaded in a second. However, this type of analysis does not always give the reliable and healthy solutions. Because, construction period of this type of the structures continue along time and loads may be changed during this period. Therefore, construction stages and time dependent material properties should be considered in the analysis to obtain the reliable and healthy results.  相似文献   
52.
本文对用惠斯通电桥测电容器的方法进行了研究和论证  相似文献   
53.
The article shows a bridge representation for the joint density of a system of stochastic processes consisting of a Brownian motion with drift coupled with a correlated fractional Brownian motion with drift. As a result, a small time approximation of the joint density is readily obtained by substituting the conditional expectation under the bridge measure by a single path: the modal-path from the initial point to the terminal point.  相似文献   
54.
A series of chelating bridge functionalized bis-N-heterocyclic carbenes (NHC) complexes of rhodium (I) were prepared by reacting the corresponding imidazolium salts with [Rh(COD)Cl]2 in an in-situ reaction. For the N-methyl substituted complex with a PF6-anion an X-ray crystal structure was exemplary obtained. All complexes were spectroscopically characterized and tested for the hydrosilylation of acetophenone.  相似文献   
55.
孙英勋 《力学学报》2005,13(4):546-550
EH4电磁成像系统是一套双源型电磁法数据自动采集和处理的物探系统,它是CSAMT和MT的结合体。本文介绍了EH4的原理、特点、工作方法和资料处理。该系统首次运用于高速公路长大深埋隧道勘察中,结合其他手段,成功解译出了隧道的软弱层、地下水及断层破碎带的位置,为划分隧道围岩类别提供了较好的依据,同时也为高速公路长大深埋隧道提供了一种新的勘察方法。  相似文献   
56.
In this paper, we construct CCRRS, complete coupling round robin schedules, for n teams each consisting of two pairs. The motivation for these schedules is a problem in scheduling bridge tournaments. We construct CCRRS(n) for n a positive integer, n?3, with the possible exceptions of n∈{54,62}. For n odd, we show that a CCRRS(n) can be constructed using a house with a special property. For n even, a CCRRS(n) can be constructed from a Howell design, H(2n-2,2n), with a special property called Property P. We use a combination of direct and recursive constructions to construct H(2n-2,2n) with Property P. In order to apply our main recursive construction, we need group divisible designs with odd group sizes and odd block sizes. One of our main results is the existence of these group divisible designs.  相似文献   
57.
Abstract  The molecular structure of [Cu2(MeCN)2(μ-tpy)2][BPh4]2 has been determined. The two terpyridine ligands coordinate to the same Cu(I) center in a bidentate configuration, in which the copper adopted a distorted tetrahedral geometry with the four nitrogen donors. The third ring of each terpyridine ligand forms a bridge with a second Cu(I) center, whose tetrahedral coordination sphere is completed by two acetonitrile ligands. The resulting structure represents a section of a double helix. Crystal data: space group C2/c, a = 27.202(5), b = 12.995(3), c = 23.409(5) ?, β = 123.13(3)°; V = 6930(2) ?3, Z = 4, R = 0.0613, wR 2 = 0.0946. Graphical Abstract  The molecular structure of [Cu2(MeCN)2(μ-tpy)2][BPh4]2 has been determined. The terpyridine ligands coordinate in a bidentate fashion to the same Cu center and monodentate to a second Cu center resulting in a double helical structural motif.   相似文献   
58.
为了将非匀一硬球流体的桥密度泛函近似扩展到非匀一非硬球流体,提出了一个理论方案.所得的LJ流体的密度泛函近似计算简单,精确.特别是密度泛函近似仅仅需要共存体相流体的二阶直接相关函数作为输入,因而可以应用于超临界与亚临界温度.所提出的理论方案可以认为是热力学理论的非匀一对应物.  相似文献   
59.
60.
Abstract

This paper proposes a pricing method for path-dependent derivatives with discrete monitoring when an underlying asset price is driven by a time-changed Lévy process. The key to our method is to derive a backward recurrence relation for computing the multivariate characteristic function of the intertemporal joint distribution of the time-changed Lévy process. Using the derived representation of the characteristic function, we obtain semi-analytical pricing formulas for geometric Asian, forward start, barrier, fader and lookback options, all of which are discretely monitored.  相似文献   
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