A general formulation of hypoplasticity

A general formulation of the theory of hypoplasticity is given, under the assumption that Cauchy stress is the only state variable. Such a formulation allows to discuss the relation between the so‐called out‐of‐axis and in‐axis moduli. It is proved that, in general, the out‐of‐axis moduli are independent from the in‐axis moduli, which allows the former to be calibrated making use of experimental shear band data, as it is done in CLoE‐hypoplasticity. The implicit assumptions made in K‐hypoplasticity are detailed for two particular models of this family. Copyright © 2004 John Wiley & Sons, Ltd.     

Group Velocity of Anisotropic Waves-Part Ⅱ: Conservative Properties

It has been argued in Part I that traditional expression of multidimensional group velocity used in meteorology is only applicable for isotropic waves. While for anisotropic waves, it cannot manifest propagation of waves group along the trajectory of a reference wave point, and varies with rotation of coordinates. The general mathematical expression of group velocity which may be used also for anisotropic waves has been derived in Part I. It will be proved that the mean wave energy, momentum and wave action density are all conserved as a wave group propagates at the general group velocity. Since general group velocity represents the movement of a reference point in either isotropic or anisotropic wave trains, it may be used to define wave rays. The variations of wave parameters along the rays in a slowly varying environment are represented by ray-tracing equations. Using the general group velocity, we may derive the anisotropic ray-tracing equations, which give the traditional ray-tracing equations for     

High-order <Emphasis Type="Italic">h</Emphasis>-adaptive discontinuous Galerkin methods for ocean modelling

In this paper, we present an h-adaptive discontinuous Galerkin formulation of the shallow water equations. For a discontinuous Galerkin scheme using polynomials up to order , the spatial error of discretization of the method can be shown to be of the order of , where is the mesh spacing. It can be shown by rigorous error analysis that the discontinuous Galerkin method discretization error can be related to the amplitude of the inter-element jumps. Therefore, we use the information contained in jumps to build error metrics and size field. Results are presented for ocean modelling problems. A first experiment shows that the theoretical convergence rate is reached with the discontinuous Galerkin high-order h-adaptive method applied to the Stommel wind-driven gyre. A second experiment shows the propagation of an anticyclonic eddy in the Gulf of Mexico. An erratum to this article can be found at     

钙原子二步三光子与三步三光子共振电离研究

激光共振电离光谱技术是痕量分析中的重要手段之一。本文以速率方程理论为基础 ,对钙原子的激光共振电离过程进行分析 ,通过编程对该原子的二步单色三光子和三步三色三光子非饱和激发电离过程进行模拟 ,得到了相应的电离效率与激光的能量、作用时间之间的关系曲线 ,并对这 2种电离方案进行了比较。     

Numerical Wave Flume Study on Wave Motion Around Submerged Plates

1 .IntroductionApile supportedplatesubmergedatacertaindepthunderseasurfacewasdevelopedasanewtypeofunderwaterbreakwaterfortheprotectionofcoastlinesandharbors .Thisisbecauseitdoesnothinderthewaterexchangebetweentheopenseaandtheprotectedareanordoesithindertheviewovertheopensea .Besides,itislessdependentonthegeotechnicalconditionsoftheseabottomwherethestructureistobeinstalled ;however,itscostishigh ,particularlyinrelativelydeepwaters .Formanyapplicationsitispossibletoreducethewavemotionintheprotec…     

非线性波传播的新型数值模拟模型及其实验验证引入变换速度变量

以一种新型的含变换速度变量的Boussinesq型方程为控制方程组,采用五阶Runge-Kutta-England格式离散时间积分,采用七点差分格式离散空间导数,并采用恰当的出流边界条件,从而建立了非线性波传播的新型数值模拟模型.对均匀水深水域内波浪传播的数值模拟,说明在引入变换速度后进一步增大了模型的水深适用范围.对潜堤地形上波浪传播的数值模拟说明,在引入变换速度后进一步提高了模型的数值模拟精度.     

CHIMEHERB—人工皮肤的毒理学试验

用CHIMEHERB人工皮肤对小白鼠和大白鼠等实验动物分别以10.20g/kg,9.60g/kg,2.98g/kg和0.96g/kg的口服剂量进行了急性毒性和长期毒性试验,结果指出:对动物的行为,体重、肝、肾等内脏器官的功能未发现任何中毒现象.对皮肤的刺激和过敏试验也证实无任何反应.     

Theoretical Analysis of Harbor Resonance in Harbor with An Exponential Bottom Profile

The general features of oscillations within a rectangular harbor of exponential bottom are investigated analytically. Based on the linear shallow water approximation, analytical solutions for longitudinal oscillations induced by the incident perpendicular wave are obtained by the method of matched asymptotics. The analytic results show that the resonant frequencies are shifted to larger values as the water depth increases and the oscillation amplitudes are enhanced due to the shoaling effect. Owing to the refraction effect, there could be several transverse oscillation modes existing in when the width of the harbor is on the order of the oscillation wavelength. These transverse oscillations are similar to standing edge waves, and there are m node lines in the longshore direction and n node lines running in the offshore direction corresponding to mode (n, m). Furthermore, the transverse eigen frequency is not only related to the width of the harbor, but also to the boundary condition at the backwall and the bottom shape.     

长江经济带空间结构演化及重组

在重新认识长江经济带的空间范围及空间结构内涵的基础上,运用空间数据分析的一般方法,获得了长江经济带空间分异的基本特征。经过独立发展阶段、区域集聚与链接阶段、 行政经济区阶段和空间竞争与链接阶段等4 个时期的发展,长江经济带形成了特殊的条形核 心-外围-边缘结构,存在三大核心、一条主轴、一条辅轴、四条地方轴、一个外围地区和 一个边缘地域。运用空间相互作用理论,从互补性、通达性和介入机会等方面分析了长江经 济带空间结构形成与演化的基础。为加快长江经济带空间结构的优化,首先要求空间管理组织的创新,其次是空间结构要素的优化。一个以政府、城市管理与经营者和具有跨国或跨区 域网络的精英企业三者组成的长江经济带空间组织与管理机构,是管理长江经济带的理想组 织模式,只有当政府、城市管理与经营者和企业建立起三者协商与联合的机制,才能进行有 效的空间管理。长江经济带的空间结构要素中,节点和通道是骨架,也是空间结构优化的两 大关键要素。