代数曲线

Let H. f and g be real polynomials in x, y of degree n+1, at most n and at most n respectively,△ be a set of h such that the real algebraic curve H =h has a compact component δ, and ω=gdx-fdy be a polynomial 1-form.

设H是n+1次实多项式，f，g为至多n次的实多项式，记△为使实代数曲线H=h有一个紧分支δ的所有h之值的集合，ω=gdx-fdy为多项式1-形式。

Given a planar point set,the moving least squaremethod is adopted to denoise and resample it so that the resulting point set is with low noise and uniform sampling density.Then the reliable signed distance field of the preprocessed point set is constructed by using the Level Set method.Finally,an algebraic B-spline function is adopted to fit the signed distance field by solving a linear equation system.

首先给定一个表示封闭曲线、可能带有噪音且分布不均匀的平面点云，采用移动最小平方(moving least square，简称MLS)方法对点云去噪、重采样，得到一个低噪音、分布均匀的"线状"点云，再通过Level Set方法建立该"线状"点云的离散几何距离场，最后用一个代数B-样条函数光顺拟合该离散距离场，代数函数的零点集即为重建曲线。

Furthermore, people found that the relationship between intrinsic properties of planar algebraic curves and the singularity ofbivariate spline spaces is m-ore and more important.

尤其是经过近年来的研究，人们发现多元样条空间的奇异性问题与代数曲线的内在性质有着越来越重要的关系。

The paper is devoted to the quartic invariant algebraic curves in quadratic system.

本文在给定参数满足一定的条件下，研究了一类二次系统的四次不变代数曲线系统平衡点的稳定性态，并运用Dulac函数法给出了该系统不存在极限环的充分条件，这一研究在同类问题中具有一定的拓展性。

This method is based on our blowup sampling method of algebraic curves, which solves the difficult problem of sampling around singular points in essence.

这种逼近建立在所提出的代数曲线胀开采样的基础上，这种胀开采样算法从本质上解决了奇异点周围采样难的问题。

By using the techniques of an explicit criterion to determine the number of real roots of a univariate polynomial in ( [13] , [73] ); B-net form of bivariate splines function; discriminant sequence of polynomial (cf. [13] , [73] ) and the number of sign changes in the sequence of coefficients of the highest degree terms of sturm sequence, this paper determines the number of real intersection points two piecewise algebraic curves whose common points are finite.

3：利用杨路，张景中，侯晓荣在文献（[13]，[73]）中关于一元多项式实根的显式判准，以及二元样条函数的B-网形式，多项式的判别序列和Sturm序列的最高次数项系数序列的变号数，本文给出了两个分片代数曲线的实交点数的计算公式。

It is suitable for all irreducible real plane algebraic curves with arbitrary genus.

它适合于任意亏格的不可约的实平面代数曲线。

Secondly, several singular point properties of piecewisealgebraic curves are discussed.

其次，简要讨论了分片代数曲线的奇点性质。

We do some research in a kind of five-order algebra curve's structure.

对一类五次代数曲线的结构进行研究。

For the regular curves, we find two Killing fields for the purpose of integrating the structural equations of the p-elastic curves and express the p-elastica by quadratures in a system of cylind...

对于正则曲线的情形，我们发现了两个用于求解p-弹性曲线的结构方程的Killing向量场并用积分将p-弹性曲线在一个柱面坐标系中表示出来，而对仿射星形曲线的情形，我们用积分方法解出了欧拉-拉格朗日方程，利用Killing向量场及线性李代数s1(2，R)、s1(3，R)和s1(4，R)的分类将高阶结构方程降为一阶线性方程，因此我们用积分完全解出了中心仿射p-弹性曲线。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。