密切曲线

This model has been applied to simulate the crack extension in three point bending creep test.

应用该模型，对三点弯曲蠕变试验中裂缝的扩展过程进行了有限元计算，发现裂缝扩展随时间的变化与应力—应变曲线的形状，尤其是强度破坏点以后的曲线形状密切相关。

The paper introduces the concept of curve following turnout branch line,the confirmation of head and end,the chord offset calculation of points,the measuring steps in the field.

道岔附带曲线是由道岔侧股引出一与导曲线成反向曲线的曲线，它与道岔有着密切的联系。

Five main phenomena were found, firstly, the high plasticity clay could well suitable to large deformation, and had strain-hardening behavior obviously, as well as, the little dilatancy; secondly, there was no correlation between stress paths and shear strength but the stress-strain relations were influenced by stress paths; thirdly, the little stress increment ratio, the higher increase speeding of shear stress and breaking strength under the condition of same initial normal stress; the fourth, the relations between normal strain and normal stress in simple shear test was consistent with which in the single-direction compression test, if there was no dilatancy; the last, the curve of relation between stress ratio and shear strain could be well simulated by hyperbola.

试验结果表明，高塑性粘土能够较好地适应大变形，接触面剪应力与切向应变关系呈剪切硬化型曲线，法向剪胀不明显；接触面剪切强度与应力路径无关，应力应变关系与应力路径密切相关；初始法向应力一定，应力增量比越小，剪应力增长越快，对应的破坏剪应力也越高；无剪胀发生情况下，法向应变与法向应力关系曲线与单向压缩试验具有一致性；应力比与切向应变呈良好的双曲线关系。

In flat space, it is not possible to close curves and go back in time.

在平板的空间，这是不可能的密切曲线和返回的时间。

First, the paper introduces the moving coordinate system based on the curve tangent vector and the curvature component vectors. Next, the total curvature vector is composed and the osculating plane determined in the moving coordinate system. The curve bending is then calculated and the recursion analysis made on the osculating plane.

鉴于空间曲线上曲率采集面的变化，引入了由曲线切向量和曲率分量决定的运动坐标系，接着在运动坐标系中合成曲率矢量，确定密切平面，然后在密切平面中对曲线进行弯曲计算和运动坐标系的变换分析，并对相关公式进行了推导。

Three preliminary conclusions could be approached as follows:(1) SST changes were distinctively characteristic of stepwise fluctuations. A warming trend during the last deglaciation was punctuated by a slightly cooling event which corresponded to the Younger Dryas. The Holocene episode could be divided into three phases of warming, continuously high temperature and cooling.(2) Two remarkable cooling records were documented around 4 kaBP and 1.5 kaBP after the megathermal of the Holocene.(3) Comparison between time series of MD05-2904 diatom R SST index and stalagmite δ^18O results from Dongge Cave, Guizhou Province suggested that changes in the East Asian Monsoon climate is synchronous with variations in the SST in the northern SCS since the last deglaciation and they might have a close correlation with each other

结果表明：(1)南海北部15 kaBP以来表层海水温度呈现明显的阶段性波动特点，即末次冰消期气候转暖过程中，12.9~11.5 kaBP前后温度略有下降，与新仙女木事件对应，全新世南海北部气候依次经历了升温期、高温期和降温期3个变化阶段；(2)全新世大暖期鼎盛期结束后，南海北部海水温度阶段下降，两次明显降温分别发生于4 kaBP前后和1.5 kaBP前后；(3) MD05-2904孔硅藻R值时间序列曲线与董哥洞D4石笋δ^18O曲线对比表明，南海北部表层海水温度变化与末次冰消期以来东亚季风强度变化关系较为密切。

The close relationship between the Hybrid polynomial approximation and the classical Hermite polynomial approximation to rational curves and surfaces are studied, Hermite approximation is in fact a special case of Hybrid approximation. The sufficient and necessary condition for the convergence of Hybrid approximation to rational Bézier surface is deduced and proved.

围绕着有理曲线曲面的Hybrid逼近，作者研究了有理曲线曲面的Hybrid多项式逼近与传统的Hermite多项式逼近之间的密切关系，并指出Hermite逼近事实上是Hybrid逼近的一种特例，此后演绎并证明了有理Bézier曲面的Hybrid多项式逼近收敛的充分必要条件。

The macroscopic rheological parameters and microstructure parameters were closely related, it is helpful to explain the essence of multiple rheological properties through the analysis of which the wax evolution process and microstructure of the crude oil which is waxy and high viscosity; the yield time of gelled waxy crude oil monotone increases along with the decreasing of rate of shear (the time of stress effect prolonged), there was power function relationship between them, it can be expressed with ; when adding diesel oil to Sudan crude oil, dilute proportion bigger the eccentricity degree of paraffin particles were bigger too, that was to say the symmetry of wax crystal was better, the wax crystal form fabric more hardly when the intermolecular interaction was smaller; in the light of macroscopica, the fall extent of the abnormity temperature, solidifying point and viscosity could be larger along with the accretion of dilute proportion, as a result, it's rheological properties could be improved.

SD原油析蜡点为94℃，析蜡高峰为50～30℃，异常点为40℃；其蜡晶颗粒细小、对称性差，所以具有较大的比表面能，容易形成联生、联锁结构；损耗角曲线与储能模量曲线或损耗模量曲线的交点所对应的温度与原油凝点或倾点温度非常接近，大约在39℃左右；也就是说，含蜡原油粘弹特性曲线的交点可以表征其流动性；原油宏观流变参数与微观结构参数密切相关，原油析蜡过程及蜡晶微观结构分析有助于诠释易凝高粘原油多重流变特性的本质；胶凝含蜡原油的屈服时间随剪切速率的降低而单调增加，二者显然存在幂函数关系，可用关系式描述；当SD原油加柴油稀释处理时，稀释比越高，蜡晶颗粒的偏心度也越大，亦即蜡晶对称性越好，分子间作用力越小，蜡晶颗粒越不易形成结构，宏观表现为异常点、凝点及表观粘度等流变参数下降的幅度越大，流动性越好。

For the application of Mathematica in the differential geometry,this paper introduces how to processe the curve curvature and the torsion questions,the graphic expression of the curvature and the torsions,and draw curves by the curvature and the torsions. Curvature ; torsion ; solution curve ; osculating plane ; natural parameter ; natural equation

利用Mathematica，只要输入有关系统命令就可以得到期望的结果。1曲率和挠率及其图形意义假设R3上的曲线一般参数表示为r=r它的曲率和挠率计算公式是：κ=‖r′×r"‖‖r′‖3τ=‖r′×r‖我们知道，空间曲线r=r在一点(s=s0)邻近的近似方程为ξ=sη=120κs2ζ=160κ0τs3通过近似方程可以确定曲线在其基本三棱形的三个平面(即密切平面，法平面，从切平面)上的投

For the application of Mathematica in the differential geometry,this paper introduces how to processe the curve curvature and the torsion questions,the graphic expression of the curvature and the torsions,and draw curves by the curvature and the torsions. Curvature ; torsion ; solution curve ; osculating plane ; natural parameter ; natural equation

利用Mathematica，只要输入有关系统命令就可以得到期望的结果。1曲率和挠率及其图形意义假设R3上的曲线一般参数表示为r=r它的曲率和挠率计算公式是：κ=‖r′×r&‖‖r′‖3τ=‖r′×r‖我们知道，空间曲线r=r在一点(s=s0)邻近的近似方程为ξ=sη=120κs2ζ=160κ0τs3通过近似方程可以确定曲线在其基本三棱形的三个平面(即密切平面，法平面，从切平面)上的投

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。