一种电子输运的矢量化Monte Carlo模拟方法

给出了一种采用SSE（Streaming SIMD Extensions)技术实现矢量化模拟电子在人体组织中输运的蒙特卡罗方法，并对一个计算放疗剂量分布的蒙卡特罗代码DPM进行了实施，将DPM模拟电子的方式由原来的一个个顺序模拟改为一次模拟4个电子，这4个电子进行同一个动作时，这部分程序可借助于SSE指令实现并行处理。计算结果显示，在不增加任何硬件成本的情况下，可以提高计算电子剂量分布的速度1．8倍左右。

Vectorized Monte Carlo simulation on the transport of electrons

With the help of SSE(streaming SIMD Extensions) technology, a vectorized MC(Monte Carlo) code for simulating the transport of electrons in radiotherapy problems is presented, which is based on DPM, a recently developed MC code. The electron transport mechanics of DPM is modified from one by one model to simulating four electrons at one time. In the parts of DPM code, where the four electrons have same actions, parallelism calculation can be achieved by SSE instructions. The result shows a 180% efficiency increase without extra hardware expense.