英语专业论文习得表

研读文献习得表阅读时间2014.05.20论文名称3D cone-beam CT reconstruction for circular trajectories词汇习得reconstruction 重建focal-spot 焦点algorithm 算法cone-beam 锥束parallel-beam 平行束rebinning 重排projection 投影filtered backprojection 滤波反投影low-intensity drop 低对比度computer tomography CThybrid 3D reconstruction technique 螺旋三维重建技术circularsource–detector 圆轨迹探测器Illuminating 照明Simplified 简化Volume 体积filter direction 滤波方向Virtual rectangular detector 虚拟探测器Summarize 总结Quality 质量，品Non-planar 曲线的句型习得1 In this paper we propose an alternative approach based on a cone-beam to parallel-beam rebinning step, acorresponding rebinning step into a rectangular virtual detector plane and a filtered backprojection.作者写这篇文章的目的是提出了一种基于数据重排的滤波反投影。

2 Based on this idea, a hybrid 3D cone-beam reconstruction method is formulated that enlargesthe reconstruction volume in its dimension along the rotation axis of the cone-beam CT system.为了解决实际的困难，提出了一种新的三维锥束重建算法。

3 This paper is organized as follows: in the following section the rebinning of cone-beam projection data to a virtual rectangular detector plane and the T-FDK reconstruction methodis introduced。

T-FDK算法的提出，锥束投影数据重排。

4 Each of these source positions generate a fan-beam in the direction orthogonal to the plane defined by the circular source path and illuminates a single detector column.5 within this plane the line integrals are located in a convex shaped area as a consequence of the varying distances from the source to this plane非中心平面与中心平面之间的关系。

6 It should be mentioned that the reconstruction method described in this section can be understood on the one hand as an extension of the fan-beam to parallel-beam rebinning technique from one- to two-dimensional detectors.虚拟语气，宾语从句。

7 The overall effect of decreasing the low-intensity drop by means of the T-FDK method is smaller than in the case of the Shepp–Logan phantom, but still visible.对于Shepp-Logan 体模，TFDK算法重建效果更好。

8 It also yields this image quality improvement in comparison to reconstruction approaches filtering along curved lines in the convex shaped plane in the centre of rotation after the cone-beam to parallel-beam rebinning (P-FDK) 。

提高图像质量的方法原理介绍。

9 A fast and efficient scheme for 3D cone-beam reconstruction from projection data obtained along circular source–detector trajectories results, which provides excellent image qualitywithin a cylindrical volume.科技论文中，长短句比较多，会出现很多的形容词或者名词的句子，在实验中论证比较充分，得到的结论篇章结构习得This paper is organized as follows: in the following section the rebinning of cone-beamprojection data to a virtual rectangular detector plane and the T-FDK reconstruction methodis introduced. In section 3 first results of this method are compared with Feldkamp’s original approach. The hybrid 3D cone-beam reconstruction technique is presented in section 4 andthe corresponding reconstruction results are discussed in sections. Finally, section 6 containsa short summary.文章先进行了简单的介绍，然后提出了T-FDK算法，第二部分介绍了算法的原理，第三部分与原始的FDK算法进行了比较，第四部分介绍了HT-FDK，进行了仿真实验，最后进行了一个简短的总结。

疑难点1 The images containing the rotation axis of the system clearly show the so-called low-intensity drop with increasing cone-angle as a consequence of missing data in Radon space.专业知识比较难理解，语句还可以。

2 Non-planar orbits are currently discussed as a solution to this problem in the framework of exact cone-beam re-construction methods句子语法比较难以理解。

3As can be seen from this schematic view, all projection data obtained along the circular source–detector trajectory contribute to the central area。

专业知识较难。

总结The idea that voxels located at different positions inside the reconstruction volume can be reconstructed from one cone-beam projection data set by using the reconstruction condition appropriate for the position leads to a hybrid T-FDK approach. The method is based on the extension of the 2D 180 reconstruction condition to the 3D case. A significant enlargementof the reconstruction volume results.A fast and efficient scheme for 3D cone-beam reconstruction from projection data obtained along circular source–detector trajectories results, which provides excellent image quality within a cylindrical volume. The overall ratio between the reconstructible and the irradiated object volume is optimized.文中在FDK算法的基础上提出了T-FDK算法，介绍了原理和实验结果，得出的效果比原始的FDK算法好。