分类: 物理学 >> 核物理学 提交时间: 2023-10-15
摘要: In -ray imaging, localization of the -ray interaction in the scintillator is critical. Convolutional neural network (CNN) techniques are highly promising for improving -ray localization. Our study evaluated the generalization capabilities of a CNN localization model with respect to the -ray energy and thickness of the crystal. The model maintained a high positional linearity (PL) and spatial resolution (SR) for ray energies between 591460 keV. The PL at the incident surface of the detector was 0.99, and the resolution of the central incident point source ranged between 0.521.19 mm. In modified uniform redundant array (MURA) imaging systems using a thick crystal, the CNN -ray localization model significantly improved the useful field-of-view (UFOV) from 60.32% to 93.44% compared to the classical centroid localization methods. Additionally, the signal-to-noise ratio (SNR) of the reconstructed images increased from 0.95 to 5.63.
分类: 核科学技术 >> 粒子加速器 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: In this paper, a genetic-algorithm-based artificial neural network (GAANN) model radioactivity prediction is proposed, which is verified by measuring results from Long Range Alpha Detector (LRAD). GAANN can integrate capabilities of approximation of Artificial Neural Networks (ANN) and of global optimization of Genetic Algorithms (GA) so that the hybrid model can enhance capability of generalization and prediction accuracy, theoretically. With this model, both the number of hidden nodes and connection weights matrix in ANN are optimized using genetic operation. The real data sets are applied to the introduced method and the results are discussed and compared with the traditional Back Propagation (BP) neural network, showing the feasibility and validity of the proposed approach.