A Fitting Study Of Nail EPR Dose Reconstruction Optimization

With the increasing use of nuclear and radiation,people are more and more likely to be exposed to ionizing radiation.When an accident occurs,how to quickly and efficiently estimate the dose and complete the classification is an important research problem in the field of Radiology and even nuclear emergency.However,when an accident occurs,it is not always possible for a personal dosimeter to provide accurate personal dose for clinical data support.Therefore,the physical or biological materials in the accident can be used for retrospective dose reconstruction to estimate the accident dose at that time.Electron paramagnetic resonance(EPR)technology can estimate the radiation dose according to the concentration of free radicals produced by radiation in human biological materials(such as enamel,nail,etc.).In dose retrospective study,the establishment of dose regression curve is not only an important prerequisite but also a crucial link in dose estimation,such as spectral subtraction.In order to establish dose regression curve with nail and provide basis for clinical classification,this paper uses C++to realize spectral subtraction with QT as the framework,simplifies the process of spectral subtraction,and visualizes it,which is convenient for users to operate interactively.At the same time,a method of nail fitting after water treatment is proposed to establish dose regression curve.In this method,the spectral line is regarded as the linear superposition of background signal and radiation signal.Based on the first-order differential function of Gaussian function,the nonlinear least square fitting(Levenberg Marquardt)of background signal and radiation signal is carried out respectively.After the simulation results are obtained,the linear fitting of each dose is carried out,and the dose after fitting is given At the same time,QT is used to program the fitting method visually,which is convenient for users to process the interface,making the fitting more concise,efficient and easy to operate.The results showed that the coefficient of determination of spectral subtraction dose regression curve was greater than 0.9,the standard error of prediction was about 1 Gy,and the efficiency was significantly improved after programming.The coefficient of determination of fitting method dose regression curve was greater than 0.9,the standard error of prediction was about 0.7 Gy,and the fitting method was better than spectral subtraction dose regression for the same batch of samples.In this paper,the spectral subtraction is programmed,and the area is used to replace the peak to peak value,so as to reduce the error caused by the line width.At the same time,the programming reduces the processing time of the spectral data,and the graphical interface is used instead.As long as the user selects the data set of the curve to be established,the regression curve can be easily established.At the same time,a more accurate fitting method is proposed and the method is programmed and interfaced to improve the efficiency of establishing dose regression.