光云

Given a planar point set,the moving least squaremethod is adopted to denoise and resample it so that the resulting point set is with low noise and uniform sampling density.Then the reliable signed distance field of the preprocessed point set is constructed by using the Level Set method.Finally,an algebraic B-spline function is adopted to fit the signed distance field by solving a linear equation system.

首先给定一个表示封闭曲线、可能带有噪音且分布不均匀的平面点云，采用移动最小平方(moving least square，简称MLS)方法对点云去噪、重采样，得到一个低噪音、分布均匀的"线状"点云，再通过Level Set方法建立该"线状"点云的离散几何距离场，最后用一个代数B-样条函数光顺拟合该离散距离场，代数函数的零点集即为重建曲线。

Finding conjugate points in the overlapped parts of scanned data sets and calculating the coordinate transformation parameters are the common steps of merging point cloud data.

透过重叠点云资料之共轭点位进行地面光达点云资料的结合是常用的方法，而空载光达的应用亦常需以共轭点位进行航带平差。

Because of ICP algorithm can identify a solution regarding the correspondence problem. In this study, I use ICP algorithm to calculate the transformation parameters of overlapped strips and compare the results with other adjusted Airborne LiDAR cloud point data to evaluate its feasibility.

本文即藉由ICP演算法能处理点云间误差的特性，对光达重叠航带的点云资料加以处理，将所得的成果进而与平差处理过后的光达点云资料做分析比较，以探讨其可行性。

Therefore, the crepuscular rays from a setting sun will appear to re-converge on the other side of the sky. At the anti-solar point 180 degrees around from the Sun, they are referred to as anticrepuscular rays.

也因此，来自落日或旭日的云隙光，视觉会在反向的天空重新会聚在一起，形成了一个和太阳相隔180度的反日点，这种光线特别被称为是反云隙光。

Data preprocessing refers to the process of polygonization, smoothing, decimation and registration. The flow and main steps of data preprocessing are described here. Several specific cases, for example the sampling method based on chordal deviation, the feature based registration, are discussed.

本文研究和讨论了点云预处理的基本流程和主要步骤，研究点云光顺的高斯滤波，中值滤波和平均滤波方法、点云精简的弦高差算法和多视点云特征对齐的方法。

Volcanoes also inject water vapor into the upper atmosphere, which can lead to night-shining clouds.

火山把水蒸气注入到高层大气之中，可以导致夜光云。

Night-shining clouds are high enough in the atmosphere that the sun still hits them, even though it's dark on the ground.

夜光云在大气层中的位置足够高使得即使地面上是夜间的时候，太阳光仍然可以照射到云层。

In addition, more night-shining clouds tend to light up the skies during times when the sun is quiet, according to Daniel Marsh of the National Center for Atmospheric Research in Boulder, Colorado.

另外，当太阳活动处于相对平静的时期，会出现更多的夜光云照亮夜空。科罗拉多州的顽石坝大气研究所的Daniel Marsh说道。

The Overfly is naked luster of the skin to glitter a golden yellow ray which shines my eyes, from the corona step, stretches out the slender white hands, and extends to me.

怡飞赤裸的玉体闪烁着金黄色耀眼的光辉，从光云里缓缓步出，纤长的玉手温柔地伸向我。

To use this method,hold the lens up with a fluorescent ceiling light in the background and view the lens surface.

要使用这个方法，停透镜与一个萤光云？？在背景中并且观看透镜表面。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。