查询词典 fitting of a curve

In this paper, a region approximation idea that means using a "fat curve" with a width to approximate the offset curve is proposed, and a complete set of algorithms to approximate offset curve using disk Bézier curve are given and implemented. In the algorithms, the optimal and uniform approximate curve of the offset curve as the central curve of the Disk Bézier curve is found by using Remez method, and then the upper optimal and uniform approximation principle is proposed to compute the error radius function of the Disk Bézier curve. Thus, the whole Disk Bézier curve can be obtained. In the end of this paper, the approximate effect of the Disk Bézier curve is not only analyzed and assessed, but also some specific examples are provided.

提出用一条带宽度的"胖曲线"来逼近上述等距曲线的区域逼近思想，并建立与实现了圆域Bézier曲线等距逼近的整套算法，包括应用Remez方法求出等距曲线的最佳一致逼近曲线作为圆域Bézier曲线的中心曲线，提出上控最佳一致逼近的原理求出圆域Bézier曲线的误差半径函数，以及确定整条圆域Bézier曲线，最后还对该圆域Bézier逼近的效果做了分析和考核，并给出了一些具体实例。

This paper establishes cubic spline function, analyzes subsection curve function and curve slope and curvature, at last decides to place the curve especial points which can be obtain easement curve length and other line parameters, such as the ZH point (end of line and beginning of transition curve), the HY point (end of transition curve and beginning of circular curve), the QZ point, the YH point (end of circular curve and beginning of transition curve), the HZ point (end of transition curve and beginning of line).

针对公路平面线形的8种组合类型，其线形元素特征则由最基本的直线、圆曲线、缓和曲线组成的特点，解析三次样条函数模型，得分段曲线函数、曲线斜率、曲率，从而确定曲线特征点（直缓ZH点、缓圆HY点、曲中QZ点、圆缓YH点、缓直HZ点）位置，进而得到曲线缓和曲线长度及其他线形参数。

Based on the discussion about fitting normal error's definition, constitution and properties, it was suggested that fitting normal error represented the error of fitting plane linear in old highway. The accuracy index of fitting plane linear in old highway based on fitting normal error was set up. The algorithm of swinging approach on compressible size step that could be used to calculate the fitting normal error was put forward. The method and basic norm of decision about fitting normal error's symbolic were discussed.

在论述拟合法线偏差定义、构成及性质的基础上，提出以拟合法线偏差表征旧路平面线形拟合偏差；建立了基于法线偏差的旧路平面线形拟合精度指标；提出了采用步长压缩摆动趋近法计算拟合法线偏差的算法，并就拟合法线偏差的符号判定准则及方法进行了讨论。

This thesis introduces the basic principle of the least square data fitting.. According to the least square data fitting ,the paper studies and analyzes the linear least square fitting ,the quantic least square fitting and nonlinear least square fitting respectively . By using the mathimatic instrument Matlab , this paper shows a lot of examples of interrelated questions. Using Matlab makes the theory of data fitting easier to be understood.

本文介绍了最小二乘数据拟合法的基本原理，并根据最小二乘数据拟合方法，分别针对线性最小二乘拟合、多项式最小二乘拟合，非线性最小二乘拟合（lsqcurvefit、nlinfit、lsqnonlin、以及非线性的线性化）、多元最小二乘拟合进行了分析和研究，并通过数学工具Matlab实现了对相关问题的举例应用，使相关数据拟合理论更加生动易懂。

Utilizing Multivariate Regression Modeling and Spectral Derivative to establish five function pattern cotton dry matter accumulation modeling based on Ratio Vegetation Index and Normalized Difference Vegetation Index,all correlation coefficient is highly positive(α=1%,n=96),based on RVI modeling has a higher precision than NDVI does,hyperbolic curve fitting,exponential curve fitting and logarithmic curve fitting have further improved analysis against cotton dry matter accumulation.

利用北疆8个棉花主栽品种(其中2个棉花品种设4水平种植密度)的各生育期冠层高光谱数据，经多元统计分析与光谱微分处理，建立了基于比值植被指数和归一化植被指数的5种函数形式的棉花干物质积累估测模型，相关系数均达到了极显著水平(α=1%，n=96)。

Based on the platform of virtual instrument LabVIEW,this paper is to detect peaks of original signal respectively with power-weighted algorithm, Gaussian fitting algorithm, Gauss- polynomial fitting algorithm, a general polynomial fitting algorithm and Gaussian non-linear curve fitting algorithm, and compare their error means and standard deviations.

基于LabVIEW虚拟仪器开发平台，分析了功率加权算法、高斯拟合算法、高斯-多项式拟合算法、一般多项式拟合算法和高斯-非线性曲线拟合算法对原始信号寻峰，比较误差均值和标准偏差。

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。

That the fitting residual errors are in the 1nm magnitude order,so the curve fitting algorithm can be used in the high-precision curve fitting exactly.

试验结果表明：该算法的拟合误差在1nm数量级，可用于完成高精度的数据曲线拟合。

Finally it analyzes the feasibility that using hydromechanics to analyze traffic flow by contrasting various characters between traffic flow and fluid flow. It analyzes influence of road alignment to basic expressway segment capacity by hydromechanics, and obtains viscous resistance and viscous movement differential equation when the vehicle drives on circular curve segment of expressway. And it infers that viscous resistance is correlated with sideway force coefficient, slope of crown and radius of circular curve. Radius of circular curve, sideway force coefficient and slope of crown are bigger, viscous resistance is smaller, the influence to capacity is smaller when the vehicle is running on nearside lane of circular curve; but radius of circular curve and sideway force coefficient are bigger, slope of crown is smaller, viscous resistance is smaller, the influence to capacity is smaller when the vehicle is running on fast lane of circular curve.

最后通过对比交通流与流体流的相似性，运用流体力学分析了道路线形对快速路基本路段通行能力的影响，求出了车辆在曲线路段的粘性阻力，建立了车辆在曲线路段的粘性运动微分方程，并由此推知，粘性阻力与横向力系数、路拱横坡度和圆曲线半径都有关系，当车辆在圆曲线外侧车道上行驶时，圆曲线半径、横向力系数和路拱横坡度越大，粘性阻力就越小，对道路的通行能力影响就越小；而当车辆在圆曲线内侧车道上行驶时，圆曲线半径和横向力系数越大，路拱横坡度越小，粘性阻力就越小，对道路的通行能力影响就越小。

Result: Scoliosis was identified in 58 cases with Marfan syndrome (38 males and 20 females), the prevalence rate was 42.03%, male-female sex ratio was 1.18:1, 6 cases were in younger than 10-year-old group. 12 cases were in 11~20-year-old group, 19 cases were in 21~30-year-old group, 11 cases were in 31~40-year-old group, 7 cases were in 41~50-year-old group, 3 cases were in 51~60-year-old group. Mean magnitude of Cobb angle in coronal plane was 26.8°±27.8°, the types of scoliosis curve included thoracic curve (36 cases), thoracolumbar curve (11 cases), lumbar curve (2 cases), double curve (6 cases) and triple curve (3 cases), apex vertebraes were convex to the right side among single curves in 38 cases while 11 cases were convex to the left side. Mean magnitude of kyphosis in sagittal plane was 14.3°±13.2°, 5 patients had thoracic lordosis and 40 patients had hypokyphosis and 12 patients had normal kyphosis.

结果：58例(42.03%)患者合并脊柱侧凸，男38例，女20例，男女患病率比例为1.18：1，其中≤10岁6例，11~20岁12例，21~30岁19例，31~40岁11例，41~50岁7例，51~60岁3例；平均冠状面Cobb角为26.8°±27.8°；胸弯36例，胸腰弯11例，腰弯2例，双弯6例，三弯3例；单弯中顶椎凸向右侧38例，凸向左侧11例；矢状面胸椎后凸平均为14.3°±13.2°，其中胸椎前凸5例，胸椎后凸不足40例，胸椎正常后凸12例，仅1例胸椎后凸45°；11例患者冠状面Cobb角＞40°，平均年龄15.9岁。

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。