查询词典 projection method

Using planar graph to express the three-dimensional objects, or a projection map to express the three-dimensional objects, must be consistent with the projection theory of descriptive geometry.

用平面图形来表达三维立体实物，或用一个投影图来表达三维立体实物，必须符合画法几何的投影理论要求。

Study results indicate that the horizontal projection length of diagonal cracks cannot be predicted accurately when considering shear span ratio and strength ratio of longitudinal steels to stirrups separately. However the horizontal projection length can be well predicted through integrating these two influence factors due to their well representation of the entire process of diagonal cracks' occurring and development.

分析结果表明，单独考虑剪跨比和纵筋－箍筋强度比都不能很好地预测斜裂缝水平投影长度，而将两者结合能够较好地反应斜裂缝出现和发展的全过程，从而准确地计算斜裂缝水平投影长度。

In order to reduce distortions of map projection, a new map projection according to the normal of ellipsoid surface is proposed in this paper.

为更大幅度地减小地图投影变形，提出了按椭球面法线投影的一种新的地图投影方法。

The work of projection from the ellipsoidal surface is not done, which avoids the projection distortion.

由于并未经过从椭球面到平面的投影，从而避免了投影变形。

First, by using the properties of knots and the Jones polynomial, we research the relation between them, thereby involving in the projection diagram with n crossings, discuss the state S of the projection diagram L , through the properties of vertexgraph, Euler Formula, one studied the problem of the equal of the knots.

首先，我们利用纽结及琼斯多项式的性质研究了它们的关系，进而涉及了有n个交叉点的纽结投影图，对其投影图L的状态S进行讨论，并通过四岔地图，欧拉公式等性质，研究了纽结等价性问题。

A set of complex Morlet wavelet are applied on projection slice of each direction to decompose each projection into several frequency channels,the average and variance extracted are computed in each frequency channel,and then linear regression model is employed to computer realationship feature between frequency channels.1-D DFT is applied to features and the amplitudes of Fourier coefficient are selected as features,then the extracted features are rotation invariant.

该算法是将一定大小的图像进行二维傅里叶变换；其次在变换后的图像中央选择一个圆盘区域，并在方向［0°，180°］内进行等间隔角度频率抽样，实现方向分解，使用一组复Morlet小波对每个方向上的映射切片进行小波变换，从而实现多通道频率分解；在各个频率通道中计算均值和方差作为特征，并利用线性回归模型计算频率通道之间的关系特征；将特征沿方向进行一维傅里叶变换并取其幅值，从而得到旋转不变性特征。

This paper systematically states the basic concept of map projection,the map projection transformation,the Gauss zone dividing porjection.

系统阐述了地图投影、地图投影变换、高斯投影及其分带投影的基本原理。

Finally, the paper presents a relatively complete plan for the reform of course system regarding such special topics as projection principles and basic drawing skills, applied foundation of projection graphics and general purpose computer assisted graphics software, mechanical drawing and general purpose computer assisted drawing software, special computer assisted drawing topics, etc.

多媒体计算机辅助教学以其声音、图像、动画、文字为一体的技术特点，为教学手段的现代化及教学课程体系的改革带来了很好的机遇。

Keywords : AFSA;neural network;coupling regress model of projection pursuit;projection direction;threshold;Hermite polynomial

应用神经网络的投影寻踪耦合回归模型存在优化问题，学习过程中运用人工鱼群算法进行优化，进而获得最佳的投影方向、阈值和正交Hermite多项式系数。

First, an initial projection matrix is obtained through homography between an image and a scene plane. The homograph matrix between two images, i. e., the image plane and the scene plane, can then be calculated from matching points of these two images. Thus the projection matrix of every next frame can be calculated from homograph matrix between the current image plane and the previous one. Registration of virtual objects is finally completed.

根据这个原理，首先通过一个景物平面和图像之间的单应得到初始状态相机的投影矩阵，然后对后面每帧图像和前一帧进行自然特徵点匹配，通过匹配点对计算出图像之间以及图像与景物平面的单应关系，由此就可以得到每一帧图像对应的相机的投影矩阵，从而完成虚拟物体的注册。

I hope that this success is just the first in a long series.

我希望这只是成功的开始。

Three dimensional stresses on the interface of tire and soil, tire deflection and soil sinkage are measured.

测试轮胎——沙土界面上的三向应力、轮胎变形和沙土沉陷；建立考虑剪切应力对沙土承载特性产生影响的车轮牵引性能预测模型；分析车轮作用下土壤的纵向稳定性。