利用PDA自身具有蓝牙通信功能、扩展SD卡、使用方便等特点,在Visual Studio 2008环境下开发一套基于Windows Mobile操作系统PDA的核数据处理与显示软件,将其设计成一种便携式核仪器的处理与显示终端。利用蓝牙通讯技术使操作人员远程操控仪器并利用便携式掌上电脑(PDA)对数据的分析,实现对放射性的快速评价,最大程度上保护操作者的安全。
A semi-empirical detector response function （DRF） model of Si （PIN） detector is proposed to fit element Kα and Kβ X-ray spectra, which is based on statistical distribution analytic （SDA） method. The model for each single peak contains a step function, a Gaussian function and an exponential tail function. Parameters in the model are obtained by weighted nonlinear least-squares fitting method. In the application, six kinds of elements＇ characteristic X-ray spectra are obtained by Si （PIN） detector, and fitted out by the established DRF model. Reduced chi-square values are at the interval of 1.11-1.25. Other applications of the method are also discussed.
针对多参数影响长距离α测量(Long range alpha detector,LRAD)系统准确度的问题,通过模拟现场管道,开展管道内LRAD敞开式测量关键参数特征研究试验,获得影响系统收集离子的特征。针对系统输入输出的非线性关系,用BP神经网络对多参数影响下系统的输出进行网络训练与预测,预测平均百分误差在5%以内。研究表明,满足放射性测量统计涨落规律条件下,BP网络对LRAD分析结果预测有较好的准确度,基本克服了系统非线性的影响。
In this paper,energy loss of alpha particles in different vacuum levels is studied experimentally and via theoretical analysis.A better understanding of energy loss of a particle in vacuum will help detect more exact numbers of alpha particles.Two ^(239)Pu sources are used to measure the energy loss of a particle crossing different vacuum levels (different air pressures).The experimental data are obtained from an instrument-PAM-100 developed by authors. The experimental results have shown that increasing vacuum levels will lead to more alpha residual energy but less energy loss.When the vacuum level reaches 0.04 MPa,alpha particles(^(239)Pu,5.115 MeV)will lose the energy of about 0.175 MeV with traversing 5 mm distance.Theoretical calculations have shown a good agreement with experimental results.This implies that the instrument has a high accuracy and could be applied in field work.
