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1.
戴俊  褚翔升  何大韧 《物理学报》2006,55(8):3979-3984
总结两个保守映象不可逆地分段连续链接(称为类耗散系统)以及一个保守映象与一个耗散映象不可逆地分段连续链接(称为半耗散系统)情况下得到的五项共同动力学特征:不连续边界象集构成的随机网成为唯一的混沌轨道;由于某些相点具有两个逆象而导致的相空间塌缩(类耗散);由于系统的不连续不可逆性质而出现的胖分形禁区网;在具有吸引子共存时占据不连续边界象集随机网和胖分形禁区网区域的点滴状吸引域以及由此导致的吸引子不可预言性;即使在传统强耗散存在的情况下点滴状吸引域仍由类耗散机制主宰.以一个累积-触发电路为例,说明这五项系统动 关键词: 随机网 禁区网 点滴状吸引域  相似文献   
2.
We present in this paper a domain decomposition method to treat faults in geological basin modeling. The particularity of this model is that the faults whose widths are very small in comparison with the basin size, are not characterized as subdomains any more but as interfaces between sedimentary blocks. The originality of this work lies in the formulation of this new fault model and in the definition and the computation of the interface conditions between the subdomains. To cite this article: E. Flauraud et al., C. R. Mecanique 331 (2003).  相似文献   
3.
In this paper, we describe an Aptian (Early Cretaceous) larger foraminiferal species Orbitolina (Mesorbitolina) parva from the limestone olistoliths in the lower part of the Yezo Group in the Yubari–Ashibetsu area, central Hokkaido and from limestone pebbles in the lowermost part of the Yezo Group in the Nakagawa area, northern Hokkaido. This is the first report of this species from the circum-North Pacific regions. Based on its occurrences, the shallow-marine carbonates, re-deposited in the lower part of the Yezo Group, are precisely assigned in age to the Late Aptian. Comparison of the lower part of the Yezo Group in central and northern Hokkaido indicates differences of the Aptian–Albian depositional history between the two areas. This study reveals that after Late Aptian, Mesogean key taxa (typical Cretaceous Tethyan biota) demised in the Northwest Pacific.  相似文献   
4.
A filled function with adjustable parameters is suggested in this paper for finding a global minimum point of a general class of nonlinear programming problems with a bounded and closed domain. This function has two adjustable parameters. We will discuss the properties of the proposed filled function. Conditions on this function and on the values of parameters are given so that the constructed function has the desired properties of traditional filled function.  相似文献   
5.
In the light of the plate tectonics the outline of paleogeography, sedimentary properties and facies patterns in the depositional processes of the Wutong Formation at the Lower Yangtze area are discussed. The argument that the Wutong Formation contains not only terrestrial sediments but also marine-terrestrial transitional or marine sediments is expounded to cover the development, evolution and paleoclimate of the Wutong depositional regions.  相似文献   
6.
Cl?(H2O)n (n = 1–4) clusters were investigated using a basin‐hopping (BH) algorithm coupled with density functional theory (DFT). Structures, energetics, thermodynamics, vertical detachment energies, and vibrational frequencies were obtained from high‐level ab initio calculations. Through comparisons with previous theoretical and experimental data, it was demonstrated that the combination of the BH method and DFT could accurately predict the global and local minima of Cl?(H2O)n (n = 1–4). Additionally, to optimize larger Cl?(H2O)n (n > 4) clusters, several popular density functionals as well as DF‐LMP2 (Schütz et al., J. Chem. Phys. 2004, 121, 737) (second‐order Møller‐Plesset perturbation theory using local and density fitting approximations) were tested with appropriate basis sets through comparisons with MP2 optimized results. DF‐LMP2 will be used in future studies because its overall performance in describing the relative binding energies and the geometrical parameters of Cl?(H2O)n (n = 1–4) was outstanding in this study. © 2013 Wiley Periodicals, Inc.  相似文献   
7.
Hopkinson non-penetrating low-speed impact test was carried out on Kevlar flexible fabrics. The impact basin was formed by the clay on the back of the fabric, and the ultimate deformation of the fabric was recorded completely. The 3D shape of the clay impact basin was measured by fringe projection profilometry and converted into the impact basin volume. At the same time, the relationship between the indentation volume and the deformation energy of the clay was calibrated using the clay intrusion test. The clay impact basin volume is then converted into the residual energy of the flexible fabric subjected to the low-speed impact, and a new index of the impact basin volume is established to evaluate the energy absorption efficiency of fabric under the low-speed impact. Finally, combined with the deformation of single-layer fabric, the stress wave propagation in the impact deformation process of fabric is discussed, which is helpful to understand the impact energy absorption mechanism of flexible fabric.  相似文献   
8.
This paper demonstrates and analyses double heteroclinic tangency in a three-well potential model, which can produce three new types of bifurcations of basin boundaries including from smooth to Wada basin boundaries, from fractal to Wada basin boundaries in which no changes of accessible periodic orbits happen, and from Wada to Wada basin boundaries. In a model of mechanical oscillator, it shows that a Wada basin boundary can be smooth.  相似文献   
9.
临夏盆地晚新生代沉积特征与青藏高原隆升   总被引:1,自引:0,他引:1  
临夏盆地是青藏高原东北边缘的一个新生代断陷盆地,盆地中的新生代沉积蕴含了丰富的环境演变等信息,并具鲜明的特征,其演化及宏观地貌结构特征的形成具有深刻的构造、气候演变及区域性特征背景,其中构造背景-青藏高原的隆升对其的影响尤为突出,其中发生了3.2MaB.P.、5.3.MaP.P.、2.4MaB.P和1.6MaB.P.的几次强烈的构造运动对于其现代地貌格局与特征的形成具有重要意义。一系列重大地质事件,如黄河于1.6MaB.P.在盆地中出现、河流阶地系列的形成和风成黄土的沉积等青藏高原的阶段性整体隆升密切相关。  相似文献   
10.
The behavior of single-degree-of-freedom systems possessing quadratic and cubic nonlinearities subject to parametric excitation is investigated. Both fundamental and principal parametric resonances are considered. A global bifurcation diagram in the excitation amplitude and excitation frequency domain is presented showing different possible stable steady-state solutions (attractors). Fractal basin maps for fundamental and principal parametric resonances when three attractors coexist are presented in color. An enlargement of one region of the map for principal parametric resonance reveals a Cantor-like set of fractal boundaries. For some cases, both periodic and chaotic attractors coexist.  相似文献   
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