Effect of Single-maze Angle on Outlet Dose Response Based on MCNP

YANG Yiwen; ZHU Yinan; LU Linyuan; ZHANG Haibin

doi:10.19554/j.cnki.1001-3563.2026.13.001

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Packaging Engineering ›› 2026, Vol. 47 ›› Issue (13) : 1-8. DOI: 10.19554/j.cnki.1001-3563.2026.13.001

Special Topic on Radiation Protection and Shielding Technologies for Multiple Scenarios in Complex Radiation Fields

Effect of Single-maze Angle on Outlet Dose Response Based on MCNP

YANG Yiwen¹, ZHU Yinan², LU Linyuan^1*, ZHANG Haibin^1*

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Abstract

To clarify the effect of continuous maze-angle variation on the normalized outlet dose response in a single-maze shielding structure, the work aims to investigate the quantitative relationship between the angle parameter and the outlet mean dose response, so as to provide a basis for low-dose angle screening and shielding structure optimization. A single-maze photon transport model was established with the Monte Carlo N-Particle Transport Code (MCNP). The angle range was set from -45° to 45° with an interval of 0.1°, resulting in 901 calculation cases. A rotating parallelogram region of interest (ROI) was defined at the outlet to extract the outlet mean dose D_mean, relative error and number of effective mesh cells. After quality filtering, y=log₁₀(D_mean) was taken as the response variable, and global polynomial fitting, piecewise sine-cosine fitting and machine learning prediction models were established. A total of 407 final fitting samples were obtained after filtering. The outlet mean dose showed obvious nonlinear variation and asymmetry between positive and negative angles, with a low-dose region near 0°. The weighted R² of the eighth-order global polynomial was 0.836 300, and the cross-validation R² was 0.828 613. The overall unweighted R² of the piecewise sine-cosine model reached 0.918 959, indicating that it could describe the cosine-like attenuation in the -45° to 0° interval and the sine-like low-dose fluctuation in the 0° to 45° interval. The Regularized XGBoost model achieved a test R² of 0.785 348, a full-sample R² of 0.857 388 on the final filtered samples, and a mean RepeatedKFold R² of 0.835 008. The single-maze angle has a significant effect on the normalized outlet dose response. The piecewise sine-cosine model is more suitable for describing the differentiated responses in the negative and positive angle intervals, and the machine learning model can be used for rapid prediction of candidate angles and preliminary screening of low-dose angles. However, key cases still need to be verified by MCNP recalculation for safety assessment.

Key words

single-maze / normalized outlet dose response / Monte Carlo N-Particle Transport Code (MCNP) / piecewise sine-cosine fitting / Regularized eXtreme Gradient Boosting (Regularized XGBoost) / error weighting

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YANG Yiwen, ZHU Yinan, LU Linyuan, ZHANG Haibin. Effect of Single-maze Angle on Outlet Dose Response Based on MCNP[J]. Packaging Engineering. 2026, 47(13): 1-8 https://doi.org/10.19554/j.cnki.1001-3563.2026.13.001

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