This paper initially applied the non-destructive evaluation-computerized tomography and the fractal theory to research the feature of wood fracture. Pinus elliottii, Populus×canadensis cv. ‘I-214’ and Larix gme...This paper initially applied the non-destructive evaluation-computerized tomography and the fractal theory to research the feature of wood fracture. Pinus elliottii, Populus×canadensis cv. ‘I-214’ and Larix gmelinii were choosed as samples. The author established the logarithm-logarithm relationship between the section area of wood fracture and its location, then defined the slope-D_L regressed by the two factors above as the section variation fractal dimension of wood fracture. The results showed: the non-destructive evaluation-computerized tomography can effectively analysis the feature of wood fracture. All the samples exist an marked linear relationship between the section area of fracture and its location, D_L is a new effective parameter to quantitatively characterize the feature of wood fracture, the delta of -2 described the complexity of fracture surface of wood. Due to the anisotropy and variation of wood properties, D_L is the statistically fractal dimension. All the results are tested by the statistic software——SARS, there exists remarkable difference between the D_L from different species. The average fractal dimension of fracture surface of Pinus elliottii is 2.25, Populus×canadensis cv. ‘I-214’ is 2.46, Larix gmelinii is 2.65.展开更多
Based on the geometrical relationships between image pixels and projection rays at different viewing angles,a Multiorientation Simultaneous Back Projection (MSBP) approach is proposed in this papar for two-dimensional...Based on the geometrical relationships between image pixels and projection rays at different viewing angles,a Multiorientation Simultaneous Back Projection (MSBP) approach is proposed in this papar for two-dimensional (2-D) parallel and fan beam CT systems. In this scheme, backprojections for eight views, 6, π/2 - θ, π/2 + 6, π- θ, π+ θ, 3π/2 - θ, 3π/2 + θ, and 2π- θ, are implemented at the same time,while the locating operation of pixels for interpolation and computation of weighting parameters are only required for one of them when one half of the number of thaws is even. Implementation remits on an Intel 80386 hosed computer show that the proposed method has a notable computational gain,compared with the conventional implementation of backprojection.展开更多
为满足借助医学图像辅助诊断的要求,提出了一种基于Apriori算法的特征融合算法:融合图像的纹理特征和医院信息系统(HIS:Hospital Information System)中病患自然特征。结合剪枝方法建立关联规则库,实现了一个可以自动将CT(Computer Tomo...为满足借助医学图像辅助诊断的要求,提出了一种基于Apriori算法的特征融合算法:融合图像的纹理特征和医院信息系统(HIS:Hospital Information System)中病患自然特征。结合剪枝方法建立关联规则库,实现了一个可以自动将CT(Computer Tomography)图像分为正常与异常两类的原型系统。依据该系统进行了评价实验。实验表明,通过该算法建立的关联规则库,对辅助医生诊断具有较好的效果。展开更多
文摘This paper initially applied the non-destructive evaluation-computerized tomography and the fractal theory to research the feature of wood fracture. Pinus elliottii, Populus×canadensis cv. ‘I-214’ and Larix gmelinii were choosed as samples. The author established the logarithm-logarithm relationship between the section area of wood fracture and its location, then defined the slope-D_L regressed by the two factors above as the section variation fractal dimension of wood fracture. The results showed: the non-destructive evaluation-computerized tomography can effectively analysis the feature of wood fracture. All the samples exist an marked linear relationship between the section area of fracture and its location, D_L is a new effective parameter to quantitatively characterize the feature of wood fracture, the delta of -2 described the complexity of fracture surface of wood. Due to the anisotropy and variation of wood properties, D_L is the statistically fractal dimension. All the results are tested by the statistic software——SARS, there exists remarkable difference between the D_L from different species. The average fractal dimension of fracture surface of Pinus elliottii is 2.25, Populus×canadensis cv. ‘I-214’ is 2.46, Larix gmelinii is 2.65.
文摘Based on the geometrical relationships between image pixels and projection rays at different viewing angles,a Multiorientation Simultaneous Back Projection (MSBP) approach is proposed in this papar for two-dimensional (2-D) parallel and fan beam CT systems. In this scheme, backprojections for eight views, 6, π/2 - θ, π/2 + 6, π- θ, π+ θ, 3π/2 - θ, 3π/2 + θ, and 2π- θ, are implemented at the same time,while the locating operation of pixels for interpolation and computation of weighting parameters are only required for one of them when one half of the number of thaws is even. Implementation remits on an Intel 80386 hosed computer show that the proposed method has a notable computational gain,compared with the conventional implementation of backprojection.
文摘为满足借助医学图像辅助诊断的要求,提出了一种基于Apriori算法的特征融合算法:融合图像的纹理特征和医院信息系统(HIS:Hospital Information System)中病患自然特征。结合剪枝方法建立关联规则库,实现了一个可以自动将CT(Computer Tomography)图像分为正常与异常两类的原型系统。依据该系统进行了评价实验。实验表明,通过该算法建立的关联规则库,对辅助医生诊断具有较好的效果。
