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At present most radiation dose meters have serious problems on aspects of energy response and angular response. In order to improve the accuracy of dose measurements, a method of average angular response has been proposed. The method can not only correct the energy response, but also the angular response. This method has been verified on NaI(Tl)(50 mm×50 mm) scintillation detectors, but has not been proved on other types and sizes of detectors, In this paper the method is also verified for LaBr 3 (Ce) scintillation detectors and HPGe detector To apply the method, first of all, five detectors are simulated by Geant4 and average angular response values are calculated. Then experiments are performed to get the count rates of full energy peak by standard point source of 137 Cs, 60 Co and 152 Eu. After that the dose values of five detectors are calculated with the method of average angular response. Finally experimental results are got. These results are divided into two groups to analyze the impact of detectors of various types and sizes. The result of the first group shows that the method is appropriate for different types of detector to measure dose, with deviations of less than 5% compared with theoretical values. Moreover, when the detector's energy resolution is better and the count rate of the full energy peak is calculated more precisely, the measured dose can be obtained more precisely. At the same time, the result of the second group illustrates that the method is also suited for different sizes of detectors, with deviations of less than 8% compared with theoretical values.

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A91transition probabilities until predicted prevalence of each health state and agespecific incidence of esophageal cancer were similar to findings from esophageal cancer screening in high-risk areas of China. Results: Annual transition probabilities were 0.024,0.05, and 0.12 for normal to mild dysplasia,mild dysplasia to moderate dysplasia, and moderate dysplasia to severe dysplasia/carcinoma in situ (CIS), respectively.Age-specific progression probabilities were 0.08-0.18 for severe dysplasia to intramucosal carcinoma,0.40-0.87 for intramucosal carcinoma to submucosal carcinoma (T1N0M0), and 0.2-0.85 for submucosal carcinoma to invasive carcinoma.As for regression,transition probabilities were 0.05 for mild dysplasia to normal,and 0.08 for moderate dysplasia to mild dysplasia,and 0.09-0.17 for severe dysplasia/CIS to moderate dysplasia.Predicted incidence of esophageal cancer increased with age, and model generated estimates for prevalence and incidence were consistent with empirical data. ConClusions: We obtain reliable transition probabilities from a Markov model based on empirical data.Our model can be potentially useful for understanding the natural history of esophageal cancer.