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By means of the dual of Said-Ball basis, the Marsden identity is got in terms of Said-Ball basis, and a degree reduction algorithm for Said-Ball curves is presented through the transform from Bezier curves to Said-Ball curves.

利用Said-Ball基函数的对偶基，得到幂基函数在Said-Ball基下的Marsden恒等式，及从Bézier曲线到Said-Ball曲线的转换。并给出Said-Ball曲线的降阶赋值算法。

In order to transfer the experimental JR curves from laboratory to real cracked components, a mathematical expression representing a family of the JR curves was constructed for steel 18G2A by using the test data of JR curves for the SENB specimens.

同时，为了将实验得到的18G2A钢的JR曲线应用于实际裂纹构件，建立了JR曲线与约束参数A2之间的关系，给出了与约束参数A2相关的JR曲线族的表达式。

Some new formulae for the derivative bounds of parametric curves, such as the general polynomial curves and rational polynomial curves in CAGD, are presented.

对CAGD中常见的多项式曲线和有理多项式曲线的导矢的界提出了新的估计公式。

Secondly, in this part, we will introduce the notation of average geodesic curvature for curves in the hyperbolic plane, and investigate the relationship between the embeddedness of the curve and its average geodesic curvature. Finally, we will employ the Minkowskis support function to construct a new kind of non-circular smooth constant breadth curves in order to attack some open problems on the constant width curves for example, whether there is a non-circular polynomial curve of constant width, etc.

其次，对双曲平面上的曲线引入平均测地曲率的概念，并讨论双曲平面上凸曲线的嵌入性与它的平均测地曲率之间的关系，其目的是为了将双曲平面上曲线的性质与欧氏平面中曲线的性质作一些对比；最后，我们利用Minkowski支撑函数构造了一类新的非圆的光滑常宽曲线，其目的是想回答有关常宽曲线的一些未解决问题如是否存在非圆的多项式常宽曲线？

Results indicate that:(1) by using HANTS, the researchers could get the EVI/NDVI harmonic curves, the mean VIs and the amplitude of the harmonics which then were utilized in the identification of the cultivated land, and EVI appeared to be more precise, with the overall accuracies of 97.17% and 95.99% and Kappa coefficients of 0.7938 and 0.6518, respectively.(2) Multiple cropping index was extracted by counting the number of the curve's peak; and when the threshold of the peak value of the NDVI and EVI curves were set as 0.25 and 0.20, respectively, the fallow land could be well figured out.(3) From harmonic curves, some eigenvalues, such as time of the maximum growth rate, time of peak and the value of peak can be extracted, based on which the crop types can be primarily distinguished. And EVI still performed better than NDVI in this section.

结果显示：（1）利用傅立叶谐波变换得到的EVI和NDVI时间谱曲线的谐波余项及谐波振幅对耕地进行识别，从识别精度来看，EVI要优于NDVI，识别精度分别为97.17%和 95.99%，Kappa系数分别达到0.7938和0.6518；（2）通过计算时间序列曲线的波峰数能够提取耕地的复种指数，并且在EVI和NDVI曲线波峰阈值分别设为0.20和0.25时，休耕地能较为准确地被识别出来；（3）通过提取作物生长期内曲线的VI最大增长速率时间点以及峰值时间点等信息，作物种类能被初步识别，并且EVI较NDVI具有更强的识别能力。

Ythagorean hodograph curves enjoy a number of remarkable properties, such as, its offset curves have exact rational representations; the arc length function of a Pythagorean hodograph curve is simply a polynomial function of the curve parameter; and the lower degree Pythagorean hodograph curves have intuitive geometrical interpretation.

H曲线具有诸如有精确的有理 Offset、弧长函数可由多项式函数表示以及几何解释优美等一系列优良性质。基于复分析方法，避免了实分析讨论中出现的复杂表示及繁琐计算，构造了满足给定 C1 Hermite插值条件且以C1拼接连续的三次 PH曲线偶。该曲线偶可灵活处理拐点，从而克服了一般三次 PH曲线因恒凸而无法处理拐点的缺陷。

In order to analyze rheological property and establish constitutive model of Q_2 loess, a series of uniaxial creep experiments on different water content are done .The creep test curves and stress-strain isochronism curves are drawed with the result of experiments and conclusions are reached from the curves. The creep performance of Q_2 loess is different under the different stress level. In the different time the stress-strain isochronism curve has obvious inflection point namely yield stress and the yield stress reduces along with the increase of water content, which can be described by exponential function.

为了分析黄土的流变特性和建立相应的本构模型，本文首先根据对不同含水量的Q_2黄土进行的一系列单轴应力条件的室内蠕变试验结果，分析总结了Q_2黄土蠕变特征和应力—应变等时曲线特征，得出Q_2黄土在不同的应力水平下蠕变变形表现形式不同；在不同的时刻应力—应变等时曲线存在有较明显的拐点，拐点所对应的应力即为屈服应力，屈服应力随着含水量的增大而呈指数形式降低；Q_2黄土可近似看成一种线性粘弹塑性体。

The technique of perturbations constraint when applied to degree reduction of Bézier curves gives fairly well results This paper discusses why these kind of technique have limitation when applied to B-spline curves, and the least squares approximation approach is presented for reducing the degree of B-spline curves Examples comparing the new method with existing ones are illustrate

将扰动约束技术应用于B啨zier曲线的降阶给出了理想的结果讨论了将这类方法应用于B样条曲线降阶时结果不理想的原因，提出了采用最佳平方逼近技术对B样条曲线做降阶运算的方法；并用实例对该方法和基于扰动约束的降阶方法进行了比

In digital process method of the I-V characteristic curves of the probe, we carry out the smooth treatment of the curves and obtain the second derivatives of the curves, using the ready-made software ORIGIN5.O. This is a simple and effective method.

在对探针特性曲线的数值处理方法上，采用了现成软件Origin5.0先对其进行光滑处理，然后进行二次微分的方法，取得了良好的效果。

In curve fitting, the speed-flow rate curve shows that the curve of 16mm pitch wheel is a line and that of 12mm pitch wheel is a down-winding curve, the speed-pressure curves of two pitches both are up-winding curves and in the resistance-flow rate curves the curve of 12mm one has lower slope than that of the 16mm one.

曲线拟合结果显示，在转速-流量曲线中，16mm螺距叶轮为一直线，12mm螺距的叶轮为一向下弯曲的曲线；转速-压力曲线显示两者都是向上弯曲的曲线；阻力-流量曲线显示12mm螺距的叶轮斜率较小。

Metrorrhagia is also gynaecological problems of common diseases.

崩漏是妇科常见病也是疑难症。

WordFTP gives you the convenience and timesaving you need.

wordftp让您的方便和省时您所需要的。