查询词典 fitting of a curve

From a neutral gray balance curve, the curve Y, m, and the basic coincideut from neutral gray balance curve, the curve Y, m, and C coincideut basic curve the Y, m into a bow-shaped curve.

而从洋性灰不均弧线来看，Y、M弧线根基重分，而从洋性灰不均弧线来看，Y、M弧线根基重分，而C弧线则矮不入Y、M成为一条弓形弧线。

In consideration of the chain grate stoker with steam capacity of 20t/h,based on experimental testing data,a fast modeling with step input,was set up by calculating transfer function on step response curve,gets model parameters on "two-point method" on the first,and then modifies those parameters with "curve fitting method" through MATLAB/SIMULINK software,proves that the combination of "two-point method" and curve fitting mothod...

对阶跃响应曲线先采用&两点法&得出模型参数，再采用&曲线拟合法&对模型参数进行修正，从而实现系统动态特性建模。着重讨论了针对阶跃响应曲线，在&两点法&建模的基础上，进一步采用在MATLAB/SIMULINK软件环境下&曲线拟合法&对模型进行修正，发现&两点法&与&曲线拟合法&相结合的方法可以更准确地对系统进行建模。此方法可为锅炉燃烧优化设计、热力系统仿真研究提供热工对象理论模型，也可用于控制系统调试时控制参数的预选择。

Two-phase-learning is adopted. The strongpoint is that intuitionistic knowledge can be used to control the segmentation by using input-weight and distant-weight. Examples prove that segmentation using SOFM network is right and efficient. Surface fitting is an absolutely necessarily process in REGM. Surface fitting includes algebraic and parametric surface fitting. Algebraic surface fitting has not extra requirement for data distribute format and boundary shape.

第三种方法把人工智能用于反向工程的数据分区，因为数据分区的实质是相似特征的聚类，而神经网络可以实现自组织特征映射，在本论文中第一次把自组织特征映射神经网络用于多视图点云的数据分区，通过神经网络对数据点的坐标、法向量等几何特征进行聚类，并且运用了快速稳定的训练方法——两阶段训练算法，最重要的是，通过距离权值和输入权值可以把用户观察所得的直观知识加入聚类过程。

Results from Monte Carlo experiments support the hypotheses that (1) fitting both surface and contour is superior, in terms of the quaality of the fit, to either surface fitting or contour fitting alone;(2) the shape of the surface is less likely to be misclassified when we use the proposed fused data fitting method.

藉蒙地卡罗方式的测验，我们得以证实：(1)线条及表面资料同时调适的结果，以调适的品质来看，会优於个别调适的方式；(2)利用对应光度及景深影像资料来侦测物体的形状，可以降低物体表面错误分类的发生。

The cubic algebraic curves (the Bezier curve and B style curve, etc belong to the parameter curve) is apter to realize the curve transition and fitting to dispersed data than the cubic parametric curves.

比如参数曲面与平面的交线就是一条平面代数曲线；平面参数曲线的等距曲线也是一条代数曲线。

First, a smooth curve is obtained from the data by curve fitting with the method of non-linear least squares fit. Then the tangent vector and the radius of curvature of each point on the curve can be calculated for the error evaluation. With the fitted curve, the focusing state of the aspheric lens can be obtained by the method of ray tracing.

主要过程为首先采用非线性最小二乘拟合的方法进行曲线拟合，并计算出曲线上各点的切矢量和曲率半径，分析它们的误差，最后对拟合后的曲线用光线追迹的方法得到非球面镜的聚焦情况。

Sphere fitting method, conicoid fitting method and line scanning curve fitting method are used to approach system error for the first time. The effect on the measurement error of each method is also analyzed.

首次利用球面拟合法、二次曲面拟合法以及行扫描曲线拟合法去逼近系统误差，并分析了各种方法进行系统误差校正时对最终测量误差的影响。

For a general parametric curve/surface, we usually cannot compute its exact implicit form. Even though its exact implicit form can be computed, the curve/surface implicitization involves relatively complicated computation and the degree is higher. Moreover, it may have unexpected components and self-intersections. All these unsatisfied properties limit the applications of the exact implicitization. So finding curve/surface approximate implicitization has become a practical problem. In this paper, we present an algorithm to solve the approximate implicitization of a given parametric curve by using a quadratic algebraic spline curve.

由于精确隐式化过程不一定可以实现，即使可以实现隐式曲线曲面的阶数高计算复杂，并且具有不希望的自交点和奇异分支，从而限制了隐式化的运用，所以寻求参数曲线曲面的近似隐式化问题成为很实际又重要的问题，提出利用二次代数样条曲线来实现一般平面参数曲线近似隐式化的一种算法。

This article first introduces the math foundation required by ECC,including the addition rule for elliptic curve point defined over finite field.Then , the principle of ECC is discussed and its security and efficiency of ECC are analyzed.Third, a cryptosystem is designed through analyzing the security requiration, choosing the elliptic curve domain parameters,denoting field element,elliptic curve and elliptic curve point,choosing associate primitves and schemes andpartitioning functional module.Forth, how to develop a crytosystem based on elliptic curve encryption algorithm is investigated.Fifth, a cryptosystem we have developed by us and the testing result is described.

本文首先介绍了ECC的数学基础，对有限域上椭圆曲线点的运算规则进行了详细描述；其次探讨了ECC的原理，分析了ECC的安全性和有效性；第三，设计了一个基于ECC的加密系统，包括系统的安全需求分析，域参数选择，域元、椭圆曲线、点的表示，原语和方案的选择，及整个系统的模块功能划分；第四，在设计的基础上，研究如何开发一个基于椭圆曲线的加密系统；第五，描述了一个我们已经设计与开发的基于椭圆曲线的加密系统，并给出了相应的测试结果。

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。

Salt is good, but if the salt becomes flat and tasteless, with what do you season it?

14：33 盐本是好的，盐若失了味，可用什么叫它再咸呢？

He reiterated that the PLA is an army of the people under the leadership of the Communist Party of China.

他重申，人民解放军是在中国共产党领导下的人民军队。