两维的

The principle of the two dimensional acoustooptic Q switch is presented,the formulas of the diffraction efficiency and diffraction loss of the AO Q switch with normal Bragg diffraction is derived,the relationship between One dimensional and Two dimensional Bragg diffraction is analyzed.

描述了两维声光Q开关的基本原理，详细推导出正常布喇格衍射的两维声光Q开关衍射效率和衍射损耗的表达式，分析了两维布喇格衍射和一维布喇格衍射之间的关系，并给出了在驱动功率40W、光束直径5mm、光波长1。

At first, the velocity which is the outlet velocity of 2-D numerical model by using the VOF and κ~εmodel is used as the inlet velocity of the 3-D numerical model. The control equations of 3-D water and sediment movement are described in the orthogonal curvilinear coordinates, and the equations is segregated by using the Finite Volume Method.

以二维的水气两相流的VOF 模型结合雷诺时均法的κ~ε双方程模型进行水气两相流计算，得到稳定流场作为三维水沙计算的初始进口条件。

It is proved that the two-dimensional non-hydrostatic Boussinesq equations on the x ? z plane with the kinetic viscous term and the thermal dissipative term are unstable equations in the C 2 function class.2. If we replace the influence of the kinetic viscous term by Rayleigh friction and the thermal dissipative term by Newton cooling, the new generalized equations are stable equations in the C 1 function class. The construction of the solution space and the discriminating method for well-posedness of the problem of determining solution are given.

本文的主要结果如下：1证明了在y方向上均匀的带有运动粘性项以及热耗散项的两维非静力、Boussinesq近似的x-z面上两维旋转流体的控制方程组在C 2函数类中是一个不稳定的方程组。2如果以瑞利摩擦来代替粘性的影响，以牛顿冷却来代替热量的耗散，则所获得的一个新的方程组在C 1函数类中是一个稳定的方程组，给出了其解空间的构造和各种定解问题的适定性的判别方法。

Professor Simon Newcomb was expounding this to the New York Mathematical Society only a month or so ago.

你们都知道，我们可以在只有两维的平面上表现一个三维的立体图。

The optical illusion occurs because our mind tries to convert a two dimensional object into three dimensions. We try to assign 3D aspects to this illusion which are not there.

产生这种现象是因为我们的潜意识里希望把两维的物体转换成三维的，所以对这张图，我们的眼睛就试图去补上并不存在的横木的两个面。

However, a strong two-dimensional design is just as important as a feeling of depth, and perhaps more important.

然而，一个两维的强大设计与一种对深度的感觉同样重要，甚至要更为重要。

Our idea of easy dimensional driving includes mainiy:(1) a driving mechanism of construction constraints and dimensional constraints,(2) automatic graphic recognition of constraints,(3) a bothway cross dimensional linked list for storing dimension sparse matrices and for recalling them,(4) a reasonable method of constraint consistence checking,(5) the linking of movement of 2D views,(6) a method for creating a sequence graphic library.

随着二维与三维设计技术的交叉发展，目前的参数化设计主要有两个分支：①面向纯二维的图形参数化，其特点是二维图形为多拓扑环的复杂图形；②面向三维的基于CSG特征造型的参数化，用于拉伸扫描的单拓扑环的二维图形参数化及空间任意曲面的参数化是其特点。

The estimation of additive and dominance effects through QTL analysis by onedimensional search while ignoring epistases showed similar accuracy to that by two-dimensional search by including epistases. Existence of epistases could decrease the precision for the estimation of additive and dominance effects. The estimation of genetic main effects would be biased if ignoring the interaction effects of QTL×environment . Joint analysis of multiple environments including QE interaction effects could increase the precision for the estimation of genetic main effects.

忽略上位性效应的一维搜索QTL分析对加性效应和显性效应的估计精度与包括上位性的两维搜索QTL分析对这两种效应的估计精度相差不大，上位性的存在可能会降低对这两种效应估计的精度；忽略QTL×环境互作效应会导致对遗传主效应的有偏估计，而包括QE互作效应的多环境联合分析能够提高对遗传主效应的估计精度。

A 2D two phase horizontal fracture model was established when studying hydraulic fractures for the requirement of shallow reservoir stimulation in this block; and a 3D two phase model has been built for numerical simulation of a reservoir with five-spot pattern without considering vertical fracture flow. The impacts of horizontal fracture half length and flow conductivity on recovery factor and ultimate recovery factor are studied for some certain injection and production conditions. The parameters of hydraulic fracturing are optimized.

根据该区块浅层油层改造的实际需要，研究水力裂缝时建立两维两相的水平裂缝模型，不考虑裂缝垂直方向上流动，建立了五点井网条件下三维两相油藏数值模拟模型，研究了水平裂缝半长和导流能力对油井产量、注采条件下的采收率和最终采收率等指标的影响，优化了水平裂缝参数。

But we are not making 2-dimensional rectangles!

但是我们不是在制作两维的长方形！

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！