Tomographic reconstruction of tokamak plasma light emission from single image using wavelet-vaguelette decomposition
Tomographic reconstruction of tokamak plasma light emission from single image using wavelet-vaguelette decomposition
复制标题
使用小波-模糊分解从单图像中托卡马克等离子体光发射的断层扫描重建
DOI：
10.1088/0029-5515/52/1/013005
复制
发表时间：
2011
期刊：
影响因子：
--
通讯作者：
P. Monier
中科院分区：
文献类型：
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作者：
R. N. yen;N. Fedorczak;F. Brochard;G. Bonhomme;Kai Schneider;M. Farge;P. Monier
安装在托卡马克装置上的摄像机所获得的图像很难解释，因为等离子体的三维结构是以一种非平凡的方式扁平化的。然而，利用缓慢变化的波动沿沿着磁场线，光学变换可以近似由广义阿贝尔变换，为此，我们提出了一种基于小波变换的反演技术。新方法的验证后，使用的学术测试用例和数值数据获得的托卡马克2D代码，我们提出了一个应用程序的托卡马克Tore Supra中获得的实验电影。与一个经典的正则化技术不适定的反问题，奇异值分解的比较，使我们能够评估的效率。小波变换的优势体现在保留局部特征，如斑点和前线，在去噪的发射率地图。
Images acquired by cameras installed in tokamaks are difficult to interpret because the three-dimensional structure of the plasma is flattened in a non-trivial way. Nevertheless, taking advantage of the slow variation of the fluctuations along magnetic field lines, the optical transformation may be approximated by a generalized Abel transform, for which we propose an inversion technique based on the wavelet-vaguelette decomposition. After validation of the new method using an academic test case and numerical data obtained with the Tokam 2D code, we present an application to an experimental movie obtained in the tokamak Tore Supra. A comparison with a classical regularization technique for ill-posed inverse problems, the singular value decomposition, allows us to assess the efficiency. The superiority of the wavelet-vaguelette technique is reflected in preserving local features, such as blobs and fronts, in the denoised emissivity map.