特征方向

Based on wave propagation feature, this paper analyses 3D seismic migration algorithms such as alternating direction implicit method, LU decomposition method, and inverse operator approach method. The result shows that the alternating direction implicit method is fast but causes distortion in wave field extrapolation and affects image accuracy; however LU decomposition and inverse operator approach methods are fast while holding circular symmetry of wave field, and are promising in oilfield exploration and development.

在波的传播特征分析基础上，对交替方向隐式法、LU分解法、逆算子逼近法等三维地震偏移算法进行了分析研究，结果表明，交替方向隐式法虽然快捷但是在波场外推中明显产生畸变并影响成像的准确性，而LU分解和逆算子逼近法是保持波场圆对称特征前提下的快速算法，在油田勘探开发中具有较好的应用前景。

The process of the algorithm include: image enhancement, using self-adapting threshold value reduce redundance, using Hough transformation extract first feature line, according to the vertical projection of the horizontal gradient perform characters line, using the improving Hough transformation with angle constraints acquire the intersection of the two feature lines, according the characters of geometry position to judge the fault.

算法流程包括图像增强，自适应阈值变换滤除无关特征，应用Hough变换提取主特征线条，依据线型特征图像水平梯度沿垂直方向的积分投影定位主特征线，基于极角约束Hough变换推出两条主特征线交点，最后根据安全链和支架的几何形态特征判读故障。

First scanning the known handwriting materials then number them ,In pretreatment, we convert the valid part of the image into a standard size, as images carries out duotone and go throw off chirp handling in order to achieve better effect.draw features from the known handwriting materials with the Co-occurence,especially,we divided a copy of handwriting into 25 little pieces with the size of 128*128 ,drawing features from every little piecese with four directions(0 degree, 45 degrees, 90 degrees as well as 135 degrees) and calculate the four major feature values( veins and the statistical quantity of veins contrast and the statistical quantity of veins consistency Shang the statistical quantity of statistical quantity as well as the veins correlation of gray scale ), preservation all the feature value that drawn from all known ma terials to the handwriting characteristic database,then input the unknown handwriting materials, also using the method of the Co-occurence to draw those features, recycling the minimum European Distance law match the unknown writing material feature value with the handwriting characteristic feature database, export the label of the known hand writing materials which is most similar to the unknown material with minimum European Distance, and then we can confirm who is the author of the unknown material.

首先将笔迹材料作为图象扫描输入，并对其进行编号。预处理部分可将笔迹图象的有效部分规范化到一个统一尺寸，接着对其进行二值化和去除噪声的处理，以便于更好的提取图像的特征。在此我们采用了灰度共生矩阵法提取手写笔迹材料的纹理特征，与以往有所不同的是，我们将一份手写材料分割成64块大小为80*80象素的子图象，每个小块都从四个方向（0度、45度、90度以及135度）来更全面的提取特征，并计算出四个最主要的特征值（纹理一致性的统计量、纹理反差的统计量、纹理熵的统计量以及纹理灰度相关性的统计量），将从所有已知材料提取的特征值保存到纹理特征库中，对于待检手写材料，同样采用灰度共生矩阵的方法提取其纹理特征，再利用最小欧氏距离分类法将从待检手写材料中提取的特征值与纹理特征库中的特征值进行比对，与欧氏距离比对值最小的相匹配，输出匹配成功的原材料的标号，进而识别出待检材料书写者的身份。

Through S-wave polarization scanning mode of ultrasonic impulse testing, rock samples with three different properties are measured to evaluate the variation of S-wave velocity in three perpendicular coordinates. By analyzing S-wave splitting of three directions and polarization of the maximum or minimum speed S-wave amplitudes, we think that the velocity orthotropy and fracture orientation observed in the grain sandstones and crack marble samples can be estimated in terms of the polarization and velocity of S-wave. Also, perpendicularity characteristics on the two types of rocks can attribute to the bedding and structure of rocks (directional grains or crystallize).

在实验室通过选择了三种不同岩性的岩石，采用超声脉冲测试方法中的横波偏振扫描方式，观测了岩石样品三个坐标方向上的横波速度变化，通过分析三个传播方向上出现横波分裂的差异，以及出现最大或最小快慢横波振幅的偏振方向发现，可从横波偏振方向和速度值判断出纹理砂岩和裂隙大理岩样品存在不同程度的速度正交各向异性和裂隙方向等特征，认为这两种岩石的正交特性的原因是岩石的层理或裂隙与岩石本身的结构构成的。

New multiscale methods can give better performance in approximating multivariate function in high-dimension space than wavelet analysis.6. A method for texture classification is presented based on Brushlet and dyadic wavelet.

该方法从矩特征和方向信息特征出发，结合Brushlet变换的方向检测特性和二进小波变换的边缘检测特性，最后利用支撑矢量机对纹理图像进行分类。

Soil organic matter is isotropous in north-south and northeast-southwest direction with stronger spatial correlation, and is anisotropic in the southeast-northwest and east-west direction with larger spatial variability.

结果表明，以土壤有机质和农用地类型为协因子的球状模型Cokriging总体插值精度最高，试验区内土壤有机质分布格局是四周丘陵和水库区含量较低，巴江河两岸的平原地区、西南角的山前冲积平原含量较高，这也是灌溉水田密集的区域；试验区内土壤有机质含量菜地分布比较均匀、空间相关性很强，而水浇地分布差异较大、空间变异性较高；土壤有机质分布在南北、东北-西南两个方向相关性较强具有各向同性特征，在东南-西北、东西方向具有各向异性特征，受到随机因素的影响变异性较大。

This algorithm can determine the optimal parting direction and gain the information about the undercuts synchronously.

该算法可解决存在多特征复杂零件脱模方向的判定问题，不但可以获得最优脱模方向，还可得到侧凹特征的相关信息。

The area of Tiaozini Sandbanks locating hi the intertidal zone is very large, which has special geomorphology characters not only from East to West parallel to bank but also from South to North vertical to bank.

位于潮间带的条子泥沙洲面积广阔，不仅具有在平行于岸方向的由西向东逐渐过渡的地貌分带性特征，同时也具有在垂直于岸方向的由北向南逐渐过渡的地貌分带性特征。

So the evolution of the tidal-basin is a reduction of the whole tidal flat, which changes and evolution can provide important evidence for the whole Radiating Sandbanks.

位于潮间带的条子泥沙洲面积广阔，不仅具有在平行于岸方向的由西向东逐渐过渡的地貌分带性特征，同时也具有在垂直于岸方向的由北向南逐渐过渡的地貌分带性特征。

According to Gabo: texture characteristics in different directions on energy distribution of the characteristics of their improvements made Gabor texture characteristics with the direction of rotation invariance.

根据Gabo：纹理特征在不同方向上能量分布的特点，对其进行了改进，使得Gabor纹理特征具有了方向旋转不变性。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。