PARALLEL IMAGE RECONSTRUCTION FOR 3-D POSITRON CT

三维正电子并行处理方案的研究 计算机断层扫描（P-CT）。计算机断层 自20世纪60年代以来，成像技术在医学中发挥了重要作用。 并有望成为一种必然的诊断技术 在未来然而，长的图像重建时间一直是问题之一。 与该技术相关的主要缺点。计算需求 未来的三维正电子CT系统将是强大的，因为巨大的 投影数据量大，重建算法耗时。它 众所周知，传统的顺序计算机不能提供 如此巨大的计算能力。因此，采用多重处理 加快重建势在必行。这个目标 研究的目的是开发高效的并行计算架构， 专用于3-D P-CT的算法，可以从 投影数据足够快的实际应用， 成本 CT图像重建包括滤波和反投影， 分析算法，估计和校正，基本上有 类似于反投影的计算结构，在迭代中 算法这将是该项目的第一步，以确定潜在的 算法的每个部分内和不同部分之间的并行性。 然后，一个平衡的多处理器系统将被设计为最优地 利用高效的并行重建来开发并行性 算法 在整个拟议的研究中，我们会特别强调 实现处理元件之间的平滑数据流。

A study on developing parallel processing schemes for -3-D positron computerized tomography (P-CT) is proposed. Computerized tomographic imaging techniques have played an important role in medicine since the early 1970's and are expected to become an inevitable diagnostic technique in the future. However, the long image reconstruction time has been one of the major drawbacks associated with the technique. The computational demand for future 3-D positron CT systems would be formidable due to the enormous amount of projection data and time-consuming reconstruction algorithm. It is well recognized that conventional sequential computer cannot provide such an enormous computing power. Therefore, employing multiple processing elements is inevitable to speed up reconstruction. The goal of this research is to develop efficient parallel computing architecture and algorithm dedicated to 3-D P-CT, which can reconstruct images from projection data fast enough for practical applications at a reasonable cost. CT image reconstruction consists of filtering and backprojection in an analytic algorithm, and estimation and correction, which basically have the similar computational structure to that of backprojection, in an iterative algorithm. It will be the first step in this project to identify potential parallelism within each part and among different parts of the algorithm. Then, a well-balanced multiprocessor system is to be designed to optimally exploit the parallelism with the efficient parallel reconstruction algorithms. Throughout the proposed study, great emphasis will be laid on achieving smooth data flow among processing elements.