查询词典 centroid

As for azimuth scalloping compensation, accurate Doppler Centroid estimation is needed. Besides, superior scalloping correction function also plays an important role which needs to be derived from specific ScanSAR azimuth parameters.

针对方位向Scalloping校正，其关键在于精确估计多普勒中心频率，同时还要根据ScanSAR模式的技术特点建立较优的Scalloping校正函数。

Assuming the initial shape of a skirt to be an n-sided cylinder, the shape of its bottom edge can be modified by changing the distance between each edge and the centroid of bottom plane according to the amplitude of sine curve at corresponding angle.

所显示是一个n支持的圆筒，它的下缘形状可以被改变每个边缘和底下飞机之间矩心的距离修改根据高度正弦曲线在对应的角度。

Fortunately, the desertification degree decreased obviously, and moderate and light desertification took the leading position. From 1986 to 2003, the spatial centroid of desertification landscape patches expanded southwestward and northeastward, giving serious threat to the ecological safety of the southeast and northeast loess gully and hilly areas.

沙漠化程度明显下降，沙漠化主导类型已由严重沙漠化转变为中度和轻度沙漠化。1986-2003年沙漠化景观整体上向西南和东北方向扩展，严重威胁着西南和东北部黄土丘陵区的生态安全。

Continuous beam models with spring supports were set up to model end-plate connections. By comparing the results from tests with those from model analysis, the following conclusions can be drawn: during loading process, the neutral axis moves from the centroid axis to compression zone, not exceeding the center line of bolts inside the compression flange; ultimately, the tension flange and end-plate can be simplified as T-stub on the assumption that the axial forces of bolts in tension zone are equal to each other.

理论计算系建立带弹性支座的连续梁模型模拟端板连接，将模型计算结果与试验结果比较分析，结果表明：加载过程中，螺栓群中和轴逐渐从其形心轴向受压区移动，但不超过受压翼缘内侧螺栓中心线；极限状态下，受拉翼缘和端板可简化为等效T型件。

Our main work is as follows: the stable laser mode theory in uniform plasmas is extended to non-uniform plasma cases; the discussion of the sufficient and necessary conditions for laser self-focusing in uniform plasmas is developed to non-uniform plasma cases; a quantitative approach to judge the impact of different plasma density distribution on laser self-focusing is proposed; the evolution properties of asymmetric laser filed in non-uniform and uniform plasmas are discussed and mechanisms that symmetric channel-like plasmas can confine the laser centroid around the plasma channel axes and symmetrize initially asymmetric laser beams are proposed; the formation of solitary standing wave in moderate plasma density is studied by PIC simulations and can be explained by stimulated Raman scattering of laser beams in plasmas.

主要工作为：把均匀等离子体中激光的稳定模理论推广到横向非均匀等离子体情形；把均匀等离子体中激光自聚焦的充分和必要条件的讨论推广到横向非均匀等离子体情形；给出横向密度分布不同的等离子体影响激光自聚焦的定量判据。讨论了初始不对称的激光场在横向非均匀及均匀等离子体中的演化特性，并提出了具有对称腔道结构的等离子体箍缩激光质心和对称化初始不对称激光场的物理机制。用粒子模拟讨论了激光场在等离子体中形成孤立驻波的过程，认为前向受激拉曼散射是发生此现象的可能机制。

The mean, maximum and minimum value of the area of transverse section and the major axis length of ellipse and the maximum centroid displacement can be used to discriminate width of pulse tracing.

长轴长度周期平均值、最大值、最小值，面积周期平均值、最大值、最小值，以及轴心在平行于皮肤表面的最大位移等参数可以作为初步判别脉宽的参数。

For example, we study the properties of the"centroid curve" and the"auxiliary curve", and identify two planes in which these two curves are defined respectively; we also use the idea of homotopy method to prove a fact that the orbit of a differential system has no triple contact point with the line we considered. Another key technique, which we use several times, is deformation argument.

例如研究由Abel积分之比定义的"质心曲线"和"辅助曲线"的几何性质，并把这两条在不同平面上定义的曲线放在同一坐标系中考虑；利用拓扑中同伦的思想来证明微分系统的轨线不可能与某条直线三重相切；利用几何方法与分析计算相结合证明了某一曲线是正则的；以及连续变动参数的技巧。

In order to reduce the cost of matching, we used multiple scale technique. 4. We presented a novel method of searching for similar fragments of 3D curves. with this method, a hash vector is associated with each fixed-length fragments of 3D sherd. Each vector consists of low frequence component of Fourier-Like spectrum for the distance between profile curve and the centroid.

依据样条曲线的基本理论，研究了基于B样条的轮廓曲线的匹配方法，给出了由轮廓曲线不变量曲率和挠率构造的相似不变量的选取以及基于相似矩阵的匹配算法，并对该算法的时间复杂度作了估计，同时，将多尺度技术引入到物体轮廓的匹配问题中。

To optimize the performance of the hybrid model,it applies k-means algorithm to perform vector clustering in the LSA vector space while the density function is used to initialize the centroid.

研究了潜在语义分析理论及其在连续语音识别中应用的相关技术，在此基础上利用WSJ0文本语料库上构建LSA模型，并将其与3-gram模型进行插值组合，构建了包含语义信息的统计语言模型；同时为了进一步优化混合模型的性能，提出了基于密度函数初始化质心的k-means聚类算法对LSA模型的向量空间进行聚类。

Based on the improvement of Taubin s discrete curvature estimation method of triangular mesh by the adoption of area and angle weighted triangle vertex normal vector calculation formula and triangle centroid weights, a novel algorithm for triangular mesh regularization is presented.

采用面积夹角加权的三角网格模型顶点法矢及三角片质心权值对Taubin的三角网格模型离散曲率计算方法进行了改进，在此基础上提出了一种新的三角网格模型优化调整方法。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。