Cosmic-ray muon sources exhibit distinct scattering angle distributions when interacting with materials of different atomic numbers(Z values),facilitating the identification of various Z-class materials,particularly r...Cosmic-ray muon sources exhibit distinct scattering angle distributions when interacting with materials of different atomic numbers(Z values),facilitating the identification of various Z-class materials,particularly radioactive high-Z nuclear elements.Most traditional identification methods are based on complex statistical iterative reconstruction or simple trajectory approximation.Supervised machine learning methods offer some improvement but rely heavily on prior knowledge of the target materials,significantly limiting their practical applicability in detecting concealed materials.To the best of our knowledge,this is the first study to introduce transfer learning into muon tomography.We propose two lightweight neural network models for fine-tuning and adversarial transfer learning,utilizing muon scattering data of bare materials to predict the Z-class of materials coated by typical shieldings(e.g.,aluminum or polyethylene),simulating practical scenarios such as cargo inspection and arms control.By introducing a novel inverse cumulative distribution-based sampling method,more accurate scattering angle distributions could be obtained from the data,leading to an improvement of nearly 4% in prediction accuracy compared with the traditional random sampling-based training.When applied to coated materials with limited labeled or even unlabeled muon tomography data,the proposed method achieved an overall prediction accuracy exceeding 96%,with high-Z materials reaching nearly 99%.The simulation results indicate that transfer learning improves the prediction accuracy by approximately 10% compared to direct prediction without transfer.This study demonstrates the effectiveness of transfer learning in overcoming the physical challenges associated with limited labeled/unlabeled data and highlights the promising potential of transfer learning in the field of muon tomography.展开更多
As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in in...As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in increasing the quality, reusability and maintainability of software.With the automatic programming model of software engineering, through the analysis for Z specification language, a feasible semi-automatic way of refinement and transformation is proposed, and the correctness of the procedure is also discussed.展开更多
基金supported by the Research Program of State Key Laboratory of Heavy Ion Science and Technology,Institute of Modern Physics,Chinese Academy of Sciences(No.HIST2025CS06)the National Natural Science Foundation of China(Nos.12405402,12475106,12105327,and 12405337)the Guangdong Basic and Applied Basic Research Foundation,China(No.2023B1515120067)。
文摘Cosmic-ray muon sources exhibit distinct scattering angle distributions when interacting with materials of different atomic numbers(Z values),facilitating the identification of various Z-class materials,particularly radioactive high-Z nuclear elements.Most traditional identification methods are based on complex statistical iterative reconstruction or simple trajectory approximation.Supervised machine learning methods offer some improvement but rely heavily on prior knowledge of the target materials,significantly limiting their practical applicability in detecting concealed materials.To the best of our knowledge,this is the first study to introduce transfer learning into muon tomography.We propose two lightweight neural network models for fine-tuning and adversarial transfer learning,utilizing muon scattering data of bare materials to predict the Z-class of materials coated by typical shieldings(e.g.,aluminum or polyethylene),simulating practical scenarios such as cargo inspection and arms control.By introducing a novel inverse cumulative distribution-based sampling method,more accurate scattering angle distributions could be obtained from the data,leading to an improvement of nearly 4% in prediction accuracy compared with the traditional random sampling-based training.When applied to coated materials with limited labeled or even unlabeled muon tomography data,the proposed method achieved an overall prediction accuracy exceeding 96%,with high-Z materials reaching nearly 99%.The simulation results indicate that transfer learning improves the prediction accuracy by approximately 10% compared to direct prediction without transfer.This study demonstrates the effectiveness of transfer learning in overcoming the physical challenges associated with limited labeled/unlabeled data and highlights the promising potential of transfer learning in the field of muon tomography.
文摘As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in increasing the quality, reusability and maintainability of software.With the automatic programming model of software engineering, through the analysis for Z specification language, a feasible semi-automatic way of refinement and transformation is proposed, and the correctness of the procedure is also discussed.