To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxeliza...To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxelization energy loss projection algorithm.First,the energy loss equation for muon transmission tomography is derived from the Bethe–Bloch formula,and the imaging region is then dissected into several units using the model voxelization method.Thereafter,the three-dimensional(3-D)imaging model is discretized into parallel and equally spaced two-dimensional(2-D)slices using the model layering method to realize a dimensional reduction of the 3-D volume data and accelerate the forward calculation speed.Subsequently,the muon energy loss transmission tomography equation is discretized using the ray energy loss projection method to establish a set of energy loss equations for the muon penetration voxel model.Finally,the muon energy loss values at the outgoing point are obtained by solving the projection coefficient matrix of the ray length-weighted model,achieving a significant reduction in the number of muons and improving the computational efficiency.A comparison of our results with the simulation results based on the Monte Carlo method verifies the accuracy and effectiveness of the algorithm proposed in this paper.The metallic mineral identification tests show that the proposed algorithm can quickly identify high-density metallic minerals.The muon energy loss response can accurately identify the boundary of the anomalies and their spatial distribution characteristics.展开更多
提出了一种基于CAD零件离散体素模型的异质材料建模方法,重点对多材料模型和功能梯度材料模型建模进行阐述,提出固定参考特征活动梯度源(Fixed reference features & active gradient sources,FRF&AGs)的概念,引入复合AGS和不同方向FR...提出了一种基于CAD零件离散体素模型的异质材料建模方法,重点对多材料模型和功能梯度材料模型建模进行阐述,提出固定参考特征活动梯度源(Fixed reference features & active gradient sources,FRF&AGs)的概念,引入复合AGS和不同方向FRF的建模算子,提高异质材料/零件建模的效率和灵活性。并将传统CAD实体建模的交、并、差等布尔算子扩展到异质材料零件的建模中。最后给出了设计实例。展开更多
基金supported by the National Key Research and Development Project of China (2016YFC0303104)the National Natural Science Foundation of China(41304090)。
文摘To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxelization energy loss projection algorithm.First,the energy loss equation for muon transmission tomography is derived from the Bethe–Bloch formula,and the imaging region is then dissected into several units using the model voxelization method.Thereafter,the three-dimensional(3-D)imaging model is discretized into parallel and equally spaced two-dimensional(2-D)slices using the model layering method to realize a dimensional reduction of the 3-D volume data and accelerate the forward calculation speed.Subsequently,the muon energy loss transmission tomography equation is discretized using the ray energy loss projection method to establish a set of energy loss equations for the muon penetration voxel model.Finally,the muon energy loss values at the outgoing point are obtained by solving the projection coefficient matrix of the ray length-weighted model,achieving a significant reduction in the number of muons and improving the computational efficiency.A comparison of our results with the simulation results based on the Monte Carlo method verifies the accuracy and effectiveness of the algorithm proposed in this paper.The metallic mineral identification tests show that the proposed algorithm can quickly identify high-density metallic minerals.The muon energy loss response can accurately identify the boundary of the anomalies and their spatial distribution characteristics.
文摘提出了一种基于CAD零件离散体素模型的异质材料建模方法,重点对多材料模型和功能梯度材料模型建模进行阐述,提出固定参考特征活动梯度源(Fixed reference features & active gradient sources,FRF&AGs)的概念,引入复合AGS和不同方向FRF的建模算子,提高异质材料/零件建模的效率和灵活性。并将传统CAD实体建模的交、并、差等布尔算子扩展到异质材料零件的建模中。最后给出了设计实例。