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111.
在综合考虑梁柱任意半刚性连接及弹性支撑特性的基础上,建立了单层多跨平面钢框架结构整体失稳的线弹性屈曲荷载的解析计算模型,并同时考虑了所有柱脚的半刚性特征,使模型的适用范围更为广泛.本模型中的半刚性连接特性通过在所有梁柱连接处设置虚拟约束弹簧实现,弹性支撑则通过在柱顶引入具有任意刚度参数的水平弹簧实现.基于上述的基本模型,通过对所有构件建立失稳状态的控制方程并引入相应的连续性条件和边界条件,建立了平面单层任意多跨框架结构整体失稳的临界荷载解析计算方法,并研制了相应的计算程序.分析结果表明,半刚性连接特性和水平支撑效应对框架结构整体稳定性的影响极为显著,而且作用于多跨框架结构柱硕竖向荷载的分布特征对结构的整体稳定性有不可忽视的影响.另外,结构的支撑刚度及节点的半刚性连接特性对单层框架整体稳定性的影响具有明显的界限性和区间效应,对此需进一步开展深入研究. 相似文献
112.
Anna Jen?ová 《Journal of Functional Analysis》2006,239(1):1-20
We present a construction of a Banach manifold structure on the set of faithful normal states of a von Neumann algebra, where the underlying Banach space is a quantum analogue of an Orlicz space. On the manifold, we introduce the exponential and mixture connections as dual pair of affine connections. 相似文献
113.
R. Vosylius 《Lithuanian Mathematical Journal》2008,48(4):463-476
We continue the investigation of regular representations of the extended Galilean group {ie463-01} acting on the smooth canonical
fiber bundle π: R
n+1 → I R
n
. First-and second-order nonholonomic affine connections Γ
1, Γ
2, Γ
1,2 are constructed using the results presented in papers [3, 4, 5, 6]. 相似文献
114.
This paper proposes a novel approach to detect hotspots using NOAA advanced very high resolution radiometer (AVHRR) for the
Jharia, Jharkhand (India) region. Jharia coalfield in Jharkhand is the richest coal bearing area in India that contains a
large number of mine fires which have been burning for several decades. In this paper, a fuzzy based methodology has been
applied for the determination of hotspots to Jharia AVHRR images based on a theoretical model that establishes relationship
among AVHRR channel 4, channel 5 and different vegetation indices. The algorithm consists of four stages: data preprocessing,
multi-channel information fusion, hotspot detection using fuzzy logic approach and validation of result. The most commonly
used existing algorithms like contextual algorithms, multi-thresholding, entropy based thresholding, and genetic algorithms
have limitation that they need some mathematical model for training in order to get the required result. The employed fuzzy
logic approach overcomes this requirement and in addition, it is flexible, tolerant of imprecise data and is based on natural
language. The results were compared with the results obtained by ground survey and a good agreement has been obtained between
observed and predicted hotspots. 相似文献
115.
Xiao-ning XIE Rui-hong YUE Kang-jie SHI Sheng WU Li-xia ZHANG 《Frontiers of Physics in China》2008,3(1):69-73
In this paper, we show that the Lax connections can yield new classical solutions with a spectral parameter of the hybrid
formulism for the Type IIB superstring in an AdS
2 × S
2 background with Ramond-Ramond flux. This series of classical solutions have the same infinite set of classically conserved
charges.
相似文献
117.
Mahuya Datta 《Proceedings of the American Mathematical Society》2000,128(12):3723-3729
Let be a principal bundle over a manifold of dimension , and let be its -dimensional Pontrjagin class. In this paper, we aim at answering the following question: Which representatives of the class can be realised as the Pontrjagin form of some connection on ?
118.
119.
We present some properties of the distributions T of the form ∑i (δpi−δni), with ∑i d(pi,ni)<∞, which arise in the study of the 3-d Ginzburg–Landau problem; see Bourgain et al. (C. R. Acad. Sci. Paris, Ser. I 331 (2000) 119–124). We show that there always exists an irreducible representation of T. We also extend a result of Smets (C. R. Acad. Sci. Paris, Ser. I 334 (2002) 371–374) which says that T is a measure iff T can be written as a finite sum of dipoles. 相似文献
120.
Cătălin Ciupală 《Czechoslovak Journal of Physics》2004,54(8):821-832
In this paper we introduce basic notions from noncommutative geometry to the quantum hyperplane: linear connections, submanifolds, distributions and we give a Frobenius type theorem for the quantum hyperplane. 相似文献