三次抛物线

According to the hypothesis of continuum, a tube with the corner strengthened is gained to make an equal of the frame-tube. B3-spline functions and parabola functions are applied to simulate the displacement functions of the frame-tube. The system of equations about the undetermined coefficients of displacement functions is deduced by using energy-variational principle, by solving which the displacement of the frame-tube is gained. Then the internal forces in the columns and beams of the former frame-tube are obtained according to the principles of elasticity mechanics.

根据连续化假设将框筒等效为角部加强筒体，将三次样条函数与抛物线函数结合假定框筒的位移函数，运用能量变分原理推导出了关于位移函数待定系数的方程组，解得位移函数待定系数进而解得框筒的位移，再根据弹性力学原理确定原框筒中梁柱的内力。

In order to discuss the rationality of various warping displacement modes, second-degree parabola, cubic parabola, fourth-degree parabola and cosine function are selected respectively. It has been demonstrated that these displacement modes have limitation to some extent, and a more reasonable mode needs to be developed.

为了探讨各种剪滞翘曲位移模式的合理性，分别选取二次抛物线、三次抛物线、四次抛物线及余弦函数等翘曲位移模式进行计算；结果表明，这些翘曲位移模式在一定程度上均存在不足，目前还缺乏一种更加合理的位移模式。

Further simplification can be achieved near the classical stability threshold, where the effective potential can be replaced by a cubic parabola (1) with a .

在经典的稳定性阈值附近可以获得进一步简化，那里有效势可以用三次抛物线（1）代替。

With the help of the chart of "Unit Cubic Parabola"presented in this paper, clvil engineers may findit more convenient to acquire the routs uf the cubic-equation.

借助本文建立的"单位三次抛物线"图线，工程设计人员可以快速图解出三次方程的根，从而进行相关的应力计算或其它分析。

The stress-strain curve of new-old concrete and HPRRC, are suggested to be modeled by two sections: the ascending section of the stress-strain curve is simulated by cubic parabola equation and the descending section is simulated by rational fraction, where the theoretical value is in good agreement with the test value.

新—老砼及HPRRC应力—应变全曲线建议采用两段式拟合：上升段采用三次抛物线方程模拟，下降段采用有理分式模拟，理论值与试验结果吻合较好。

I was a university student, I had not done a very complex programming exercise, This is the first time I upload source. this is the upload computer graphics, I do exercises at the WIN-TC environment prepared by some of the procedures, these are the basic 2D graphics transform (translation, rotation, Shear, Zooming, symmetric) animation demonstration, three-dimensional map of the two-dimensional plane of the hidden map, the lines cut, the parabolic mapping and B-spline curves mapping, detailed procedures of the Notes, and I hope to the students friends to help.

详细说明：我是一名大学的学生，我没有做过很复杂的编程练习，这也是我第一次上传源程序，这次上传的是我做计算机图形学的练习时在WIN-TC环境下所编的一些程序，其中有二维图形的基本变换（平移，旋转，错切，放缩，对称）的动画演示、三维图在二维平面上的消隐图的显示、线条的裁减、抛物线的绘制以及B样条曲线的绘制，程序中有详细的注释，希望对学生朋友们能够有所帮助。

Furthermore,it can represent the elliptic curves,parabola and other quadratic curves without using rational form.

给出了一种基于三角函数的类三次参数曲线，该曲线不仅具有类似于三次Bézier曲线的诸多性质，而且无需有理形式即可精确地表示椭圆、抛物线等二次曲线。

The continous prestressed concrete girder bridge is divided into three inters,(30m+50m+30m), with the main span of 50m, and 30m-symmetry one.

本预应力混凝土连续梁桥共分为三跨（30m+50m+30m）主跨50m，边跨对称30m；主梁采用单箱单室预应力混凝土箱梁，跨中梁高为1.5m，支座处梁高为2.8m，截面高度按二次抛物线形式变化；桥面净宽为7+2×1.5m；设计荷载为公路-Ⅰ级。

In order to design optimum nozzle for air-air missile solid rocket motor, the mass model of solid rocket motor, the nozzle specifice impulse model of solid rocket motor and the objective function are established. Five different type of nozzles are choosen lor calculation: Conical, parabolidal,two different arcs,quadiatic polynominal and cubic polynominal.

以两种空-空导弹固体火箭发动机喷管作为算例，为此，建立固体火箭发动机的质量模型，喷管的质量比冲模型和目标函数模型，选择五种喷管扩散段内型面：锥形喷管，抛物线喷管，双圆弧喷管，二次多项式喷管和三次多项式喷管，进行优化设计，利用优化理论，成功地完成了五个设计变量的优化问题。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。