查询词典 length of curve

Length of Fourier transform is connected with curve resolution. Curve resolution is lower, window length of Fourier transform is narrower.

为截取最强地层响应信号，选取Fourier变换窗函数，窗长与曲线原始分辨率有关，分辨率越低的曲线窗长越大。

This dissertation investigates the construction of pseudo-random sequences (pseudo-random numbers) from elliptic curves and mainly analyzes their cryptographic properties by using exponential sums over rational points along elliptic curves. The main results are as follows:(1) The uniform distribution of the elliptic curve linear congruential generator is discussed and the lower bound of its nonlinear complexity is given.(2) Two large families of binary sequences are constructed from elliptic curves. The well distribution measure and the correlation measure of order k of the resulting sequences are studied. The results indicate that they are "good" binary sequences which give a positive answer to a conjecture proposed by Goubin et al.(3) A kind of binary sequences from an elliptic curve and its twisted curves over a prime field F_p. The length of the sequences is 4p. The "1" and "0" occur almost the same times. The linear complexity is at least one-fourth the period.(4) The exponential sums over rational points along elliptic curves over ring Z_ are estimated and are used to estimate the well distribution measure and the correlation measure of order k of a family of binary sequences from elliptic curves over ring Z_.(5) The correlation of the elliptic curve power number generator is given. It is proved that the sequences produced by the elliptic curve quadratic generator are asymptotically uniformly distributed.(6) The uniform distribution of the elliptic curve subset sum generator is considered.(7) We apply the linear feedback shift register over elliptic curves to produce sequences with long periods. The distribution and the linear complexity of the resulting sequences are also considered.

本文研究利用椭圆曲线构造的伪随机序列，主要利用有限域上椭圆曲线有理点群的指数和估计讨论椭圆曲线序列的密码性质——分布、相关性、线性复杂度等，得到如下主要结果：(1)系统讨论椭圆曲线-线性同余序列的一致分布性质，即该类序列是渐近一致分布的，并给出了它的非线性复杂度下界；(2)讨论两类由椭圆曲线构造的二元序列的"良性"分布与高阶相关性(correlation of order κ)，这两类序列具有"优"的密码性质，也正面回答了Goubin等提出的公开问题；(3)利用椭圆曲线及其挠曲线构造一类二元序列，其周期为4p(其中椭圆曲线定义在有限域F_p上)，0-1分布基本平衡，线性复杂度至少为周期的四分之一；(4)讨论了剩余类环Z_上的椭圆曲线的有理点的分布估计，并用于分析一类由剩余类环Z_上椭圆曲线构造的二元序列的伪随机性；(5)讨论椭圆曲线-幂生成器序列的相关性及椭圆曲线-二次生成器序列的一致分布；(6)讨论椭圆曲线-子集和序列的一致分布；(7)讨论椭圆曲线上的线性反馈移位寄存器序列的分布，线性复杂度等性质。

Namely, the first, the beginning, end and length of growing season of every type of vegetation is estimated with threshold method and moving average method, and the beginning end and length of growing season of vegetation from 1982 to 1999 is fitted linearly, finally, linear trend of the beginning end and length of growing season of vegetation is analyzed. The second, phenological phase in different years and zones is estimated based on greatest changes of slope method and EOF analysis method, and the result monitored by the two methods is compared, as a result, trend of growing season change from 1982 to 1999 in different latitude zones is better acquired. The third, phenological phase of vegetation in different spatial location from 1982 to 1999 is fitted based on curve. Then, spatial difference rules of growing season of every year and average of multi-year is discussed in article. In the end, lag correlation and linear regress are used to study relation between phenological phase of different types of vegetation, different latitude zones, different spatial places and climate changes.

利用阈值法和滑动平均法逐年估测了每种植被类型的生长季的开始、结束日期及长度；对18年中植被生长季的开始、结束时间和长度进行一次线性拟合，分析了植被生长季的开始、结束日期和长度的线性变化趋势；基于最大变化斜率法和EOF分析法估计了不同年份、不同区域内植被生长季的开始、结束时间及其长度，并对这两种方法的监测结果作了比较，从而得到了较好的不同纬度区域1982～1999年植被生长季的变化趋势；基于曲线拟合了1982～1999年的不同空间位置的植被物候期，然后讨论了每年和多年平均的植被生长季的空间分异规律；最后利用时滞相关分析和线性回归研究了不同类型植被的物候期与气候变化的相互关系，不同纬度带的植被物候期与气候变化的相互关系，植被物候期与气候变化空间相互关系。

The curve length of the QRS complex is longer than that of other parts of the ECG in the same interval, so that the ECG curve length characteristic is suitable for QRS dctcction. Our algorithm not only detects the QRS complex position but also its duration.

该算法根据QRS复合波的曲线长度在一定的等时间间隔内大于ECG其他部分的特性进行QRS波的信息提取，其不但检测QRS波的位置，而且同时检测出QRS波的宽度。

Based on the full three-dimensional numerical simulation for the centrifugal pump, an optimal mathematical model of blade curve is set up. In this model, the object function is the minimum length of the blade curve; the constraint condition is no recirculation atr=0.5. This model makes the design of optimum blade curve efficient.

在对离心泵内部流场进行全三维数值模拟的基础上，建立了叶片型线优化设计的数学模型以叶片长度最短为目标函数，叶轮相对半径，r=0.5处无回流为约束条件，讨论了该模型优化计算的方法。

By projecting 3D models into 1D smooth principal curves, equally segmentation and sampling along the length of curve are implemented to extract shape feature vectors, then one can retrieve 3D model according to the matching result of shape feature vectors of 1D manifold.

本文将三维网格模型，投影为三维的光顺主曲线；通过对主曲线沿弧长方向的均匀分割采样，提取主曲线的空间位置和姿态等形状特征；最后通过形状描述向量的比较实现了对应的三维模型检索。

For the image with random field feature, the description language is probability distribution model, and the description length equals the negative base-two logarithm of the probability of the image data; For the region homogeneity properties of active contour, the description language is chosen as a sign gradient map, and the description length is the summation of sign gradient inside the active contour; For the active contour regularity, the description language is smoothness, and the corresponding description length is the length of active contour curve.

随机场图像的描述语言采用概率分布模型，描述长度是围道内外区域中图像数据概率的以2为底对数的负数；活动围道区域一致性的描述语言为有符号的梯度图，描述长度是围道内区域有符号梯度的总和；围道形态的描述语言采用平滑性，描述长度正比于围道的长度。

The design of the 3-dimensional trajectory in horizontal wells is an optimal control system where the state variables are azimuth, inclination and the control variables are radius, tool-face angle and length of curve.

水平井三维轨道设计是以方位角、井斜角为状态变量，以曲线半径、装置角、曲线段长为控制变量，以入靶精度等为性能指标的非线性多阶段最优控制系统。

For drawing the parameter curve by point to point it orde to the parameter t's step length of increased make the progress range of the curve can not large than the length of one pels, otherwise the curve may step over one middle pels and skip one point that it should be on the curve.

要逐点地生成参数曲线，就要求参数t每次增加的步长要使曲线前进的幅度不得超过一个象素长度，否则有可能跨过一个中间象素而产生断点。

This dissertation investigates the construction of pseudo-random sequences (pseudo-random numbers) from elliptic curves and mainly analyzes their cryptographic properties by using exponential sums over rational points along elliptic curves. The main results are as follows:(1) The uniform distribution of the elliptic curve linear congruential generator is discussed and the lower bound of its nonlinear complexity is given.(2) Two large families of binary sequences are constructed from elliptic curves. The well distribution measure and the correlation measure of order k of the resulting sequences are studied. The results indicate that they are "good" binary sequences which give a positive answer to a conjecture proposed by Goubin et al.(3) A kind of binary sequences from an elliptic curve and its twisted curves over a prime field F_p. The length of the sequences is 4p. The "1" and "0" occur almost the same times. The linear complexity is at least one-fourth the period.(4) The exponential sums over rational points along elliptic curves over ring Z_ are estimated and are used to estimate the well distribution measure and the correlation measure of order k of a family of binary sequences from elliptic curves over ring Z_.(5) The correlation of the elliptic curve power number generator is given. It is proved that the sequences produced by the elliptic curve quadratic generator are asymptotically uniformly distributed.(6) The uniform distribution of the elliptic curve subset sum generator is considered.(7) We apply the linear feedback shift register over elliptic curves to produce sequences with long periods. The distribution and the linear complexity of the resulting sequences are also considered.

本文研究利用椭圆曲线构造的伪随机序列，主要利用有限域上椭圆曲线有理点群的指数和估计讨论椭圆曲线序列的密码性质——分布、相关性、线性复杂度等，得到如下主要结果：(1)系统讨论椭圆曲线-线性同余序列的一致分布性质，即该类序列是渐近一致分布的，并给出了它的非线性复杂度下界；(2)讨论两类由椭圆曲线构造的二元序列的&良性&分布与高阶相关性(correlation of order κ)，这两类序列具有&优&的密码性质，也正面回答了Goubin等提出的公开问题；(3)利用椭圆曲线及其挠曲线构造一类二元序列，其周期为4p(其中椭圆曲线定义在有限域F_p上)，0-1分布基本平衡，线性复杂度至少为周期的四分之一；(4)讨论了剩余类环Z_上的椭圆曲线的有理点的分布估计，并用于分析一类由剩余类环Z_上椭圆曲线构造的二元序列的伪随机性；(5)讨论椭圆曲线-幂生成器序列的相关性及椭圆曲线-二次生成器序列的一致分布；(6)讨论椭圆曲线-子集和序列的一致分布；(7)讨论椭圆曲线上的线性反馈移位寄存器序列的分布，线性复杂度等性质。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。