半无限的

Then, for the first time, a finite element model of the cylindrical shell surface was bring forward and set up.

首次提出和建立了柱体坐标系下的曲面柱壳单元有限元模型，以及在柱坐标系下的边界元法基本方程和柱坐标系下无限域与半无限域基本解。

After determining the control equation and defined problems for infiltration, redistribution and evaporation, implicit finite difference method was used for ponded infiltration, semi-infinite soil redistribution and semi-infinite evaporation. The calculated results agreed well with measured data.

9在确定了入渗、再分布及蒸发的控制方程及定解问题基础上，采用隐式差分格式对垂直一维积水入渗、半无限土体再分布及半无限土体蒸发进行了数值模拟，与计算结果对比表明，计算值与实测值比较符合。

The result showed that,if only the necessary but insufficient condition,the equilibrium condition ,was adopted to deal with the infinite uncertain boundary condition,the solution to the stress was non-unique due to the fact that the boundary problem here was a mal posed mathematic problem.

通过两个典型的半无限体实例，对水平表面作用无限均布压力下弹性地基的应力和位移解答进行研究，结果表明：对边界条件不明确的无限边界仅采用解答的必要非充分条件——平衡条件来等效处理，其应力解答不是唯一的，因为此时该边值问题不是一个适定的数学问题。

According to a semi-infinite truncated cone model, in Laplace space the approximate analytical solutions of the bottom surface of rigid circular plate and semi-infinite viscoelastic medium are obtained and the calculating model and formulae of seismic forces are presented.

根据半无限截头圆锥模型，在拉氏空间中获得刚性圆板底面与半无限弹性介质相互作用的近似分析解，提出了刚性圆板地震力计算模型及计算公式。

According to two logical judgements, the relation of the semi-infinite plane strain problem and semi-infinite spatial problem is found through analyzing the classical answer of wedge, semi-infinite plane, cone and semi-infinite spatial etc. The Flament answer of semi-infinite plane strain problem and the Boussinesq answer of semi-infinite spatial problem are confinable from the relation.

根据两个合理的判断依据，对弹性力学中的楔形体、半平面体、圆锥体和半空间体等经典解答进行了比较分析，发现了半无限平面应变问题和半空间体问题解答之间的关系；通过对解答之间的关系进行研究分析指出，弹性力学中的半无限平面体的符拉芒解答和半空间体的布希涅斯克解答存在局限性。

For the problem of the ratio of inner to outer diameter of long tube, according to the "residual core" in the target plays an important role in DOP of long tube penetrator, the analytical model of long tube pentration in semi-infinite homogeneous steel target is established and calculated to devide three kinds of different scopes, the rule of varied by the ratio of inner to outer diameter is analyzed. The patterns of penetration of the yawed tubular against a normal homogeneous semi-infinite target is established, the size and direction of "residual core" is analyzed, under the different impact yawed, the regularity of variations in the yawed of the tube and depth of the penetrateion is described during the penetrateion against the plate.

二是对于长管体的不同内外径比，依据长管体时形成的中间&靶芯&是其侵彻机理不同于长杆体的重要因素，分三种情况建立了长管体对半无限均质靶板的简化理论模型，并进行了分析，得出了穿深随内外径比变化的规律；描述了带攻角长管体垂直侵彻半无限厚靶的物理图像，分析了&靶芯&力的大小和方向，建立了侵彻简化模型，给出了在不同的初始攻角条件下，管体在侵彻过程中攻角和穿深的变化规律。

C The semi-infinite crack propagating in infinite region with the fiber bridging traction action is equal to the semi-infinite crack propagating in strip.

(3)受桥联纤维力作用的半无限长裂纹在无限域中扩展等效于半无限长裂纹在带域中扩展。

The conclusions are: The sonic velocity determined by the material's properties is the upper limit of the crack velocity; Bridging fibers plays a key role in increasing the composite's toughness and stopping the crack's propagation; The semi-infinite crack propagating in infinite region with the fiber bridging traction action is equal to the semi-infinite crack propagating in strip.

结论有：(1)由材料性能决定的音速是裂纹传播速度的上限；(2)桥联纤维在增韧复合材料和组织裂纹扩展中起了关键作用；(3)受桥联纤维力作用的半无限长裂纹在无限域中扩展等效于半无限长裂纹在带域中扩展。

A particular class of problems, known as Grand Challenge problems, are problems whose full solution requires semi-infinite computing resources.

某一特定类别的问题，被称为大挑战问题，这些问题的全面解决方案需要半无限的计算资源。

The dynamic propagation problem of semi-infinite mode Ⅲcrack in an orthotropic infinite body is investigated.

研究了无限大正交异性材料中半无限长Ⅲ型裂纹的动态扩展问题。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。