线元

This paper presents a new method for an estimation of the axis of rotation based on line element geometry and kinematic equation.

提出了一种基于线元几何与运动方程的旋转体点云数据特征分离与旋转轴提取算法。

For the studies of GIS uncertainty, error band model of a line segment is one of the current focus issues, which reason is not only that there are many open questions for the uncertainty of line segment but also that the uncertainty of line segment is the base of both the uncertainty of the surface element and GIS spatial analysis.

对GIS不确定性的研究来说，线元不确定性的研究是一个重点，因为线元不仅是面域不确定性的基础，其本身也是GIG叠置分析、缓冲区分析和空间地址配对分析等的基本元素。

The earliest proposed line element error band theory is "ε-band" model,then "E-band" model was proposed and developed to "G-band" model.

最早提出的线元误差带理论为"ε-带"模型，后来又提出了"E-带"模型和在其基础上发展的"G-带"模型。

Thirdly, three indexes are given to measure the precision of the line uncertainty based on the e model: the visualization graph, the average error band width and the error band area.

给出了基于该模型衡量线元位置不确定性的三种度量指标：可视化图形、平均误差带宽和误差带的面积。

Secondly, the analytic expressions of the error band boundary line for the s model of line segment are deduced, the parameter equations of the error band boundary are gotten.

考虑实用性和合理性，将线元看成离散点的集合，将线的不确定性看成点的不确定性的聚合体，将线元的位置不确定性模型看成以各点误差椭圆的长半轴E为半径的误差圆的聚合体，建立了以线元上任意点处的误差椭圆的长半轴E为带宽的线元不确定性ε模型。

The latter two all reckon that basic shape of line element error band based on control points error is "dumbbell-shape",i.e.error in control end points is larger than points error between two control points.

后两者均认为以控制点点位误差描述的线元的误差带的基本形状呈"哑铃"形，即认为线元上端点的位置不确定性大于端点之间的点的位置不确定性。

The subsection integral is used to get a simple function at first in the numerical calculation, and boundary integral is realized by gauss integral on each panel and line, then the complexity and isstability as a result of the high frequency surge function can be avoided.

数值计算中，首先采用分部积分对被积函数进行简化处理，然后采用高斯积分实现面元和线元上的积分，避免了被积函数为高频振荡函数所带来的数值计算的复杂性和不确定性。

This paper proposes an oppositional opinion to a popularly acceptedissue in GIS community about error-band of line element position uncertainty.

对当前GIS界流行的以点位误差描述线元位置不确定性的误差带理论提出相反的观点。

The authors view is oppos...

笔者的看法与此相反，笔者认为线元上两控制点之间的点的位置不确定性应大于控制点的位置不确定性，且在两控制点的中间达到最大，即线元误差带的基本形状应为&纺锤形&而不是&哑铃形&。

Horizontal alignment of a road is defined by polyline (straight line, circular curve, transition curve).

道路路线是由不同线元（直线、圆曲线、缓和曲线）组合而成的，随测点与哪个线元相关。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。