Observation of 3 - dimensional Internal Structure of Rock Using X - ray CT : (1) Density Calibration of CT Value
Observation of 3 - dimensional Internal Structure of Rock Using X - ray CT : (1) Density Calibration of CT Value
复制标题
利用X射线CT观察岩石三维内部结构：（1）CT值的密度校准
DOI：
10.6010/geoinformatics1990.8.4_239
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
H. Ohtsuka
中科院分区：
文献类型：
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作者：
T. Nakano;Koichi Nakamura;Toshiaki Someya;H. Ohtsuka
为了观察和分析各种岩石样品的内部结构，利用工业用高强度X射线CT扫描仪获得的数据重建了三维CT图像。采用滤波反投影(FBP)方法从X射线强度数据重建CT图像。图像的空间分辨率和大小分别为0.2×0.2×1和1024×1024×320像素(体素)。CT值(对象的X射线线性吸收系数)被存储为图像中每个像素上的16位整数。使用已知密度的标准样品对图像中的CT值进行密度校准。采用了新的校正方法来校正边缘区域低CT值对每个样本的平均CT值的影响。使用校准的结果，根据CT值确定CT图像中对象的密度，判定误差约为0.3g/cm3。
:To observe and to analyze the internal structures of various kinds of rock samples, a 3-dimensional CT(Computerized Tomography)image was reconstructed from the data obtained by an industry X-ray CT scanner with high intensity X-ray beam. FBP(Filtered Back-Projection)method was used for the reconstruction of the CT image from the X-ray intensity data. Spatial resolution and size of the image were 0.2×0.2×1 and 1024×1024×320 pixels (voxels), respectively. CT value(X-ray liner absorption coefficient for the object)was stored as a 16 bits integer on each pixel in the image. Density calibration of the CT value in the image was performed using the standard samples with known densities. New methods were applied to the calibration to correct the effect of low CT values in the edge region on the mean CT value of each sample. Using the result of the calibration, density of an object in the CT image was determined from the CT value with decision error of about 0.3 g/cm3.