通过机器学习方法通过电子密度及其应用估计质子停止功率比和平均激发能量
1Department of Mathematics, University of Nigeria, Nsukka, Enugu, Nigeria.
Journal of medical physics
|August 12, 2024
概括
本研究提出了一种灵活的方法,用于使用相对电子密度准确估计制止功率比率 (SPR) 和平均激发能量 (I). 与现有方法相比,开发的模型表现出强大的性能和较低的测试误差.
科学领域:
- 医学物理 医学物理
- 计算物理 计算物理
背景情况:
- 准确估计停止功率比率 (SPR) 和平均激发能量 (I) 对于辐射剂量测量和医学成像至关重要.
- 计算这些参数的现有方法可能很复杂,可能缺乏灵活性.
研究的目的:
- 开发一种简单,灵活和准确的方法来估计SPR和平均激发能 (I) 基于相对电子密度 (ρe).
- 通过现有技术验证拟议的方法,并评估其性能.
主要方法:
- 制定SPR,平均激发能量 (I) 和相对电子密度 (ρe) 之间的经验关系.
- 使用优化工具估计模型系数.
- 应用基向量方法 (BVM) 和Hunemohr和Saito (H-S) 方法进行 ρe 估计.
- 使用80kVp和150kVp Sn X射线光谱的双能量方法实现.
主要成果:
- 拟议的方法实现了SPR的建模误差≤0.32%,测试根平均平方误差 (RMSE) ≤0.92%,平均误差接近0.00%.
- 对平均激发能 (I) 的建模RMSE为2.12%,表明进一步改进的潜力.
- 与其他方法相比,该方法在BVM应用时显示了可比或优异的结果.
结论:
- 开发的方法是稳健的,可以准确估计SPR和平均激发能量 (I).
- 该方法的灵活性允许使用机器学习算法进行潜在的增强,以改进组织分类和模型程度.
- 它为现有方法提供了一个有希望的替代方案,在大多数应用中显示较低的测试错误.
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