论文标题
部分可观测时空混沌系统的无模型预测
Complex Observation in Electron Microscopy VIII: Novel Hilbert Phase-plates to Maximize Phase-contrast Sensitivity
论文作者
论文摘要
储层计算是预测湍流的有力工具，其简单的架构具有处理大型系统的计算效率。然而，其实现通常需要完整的状态向量测量和系统非线性知识。我们使用非线性投影函数将系统测量扩展到高维空间，然后将其输入到储层中以获得预测。我们展示了这种储层计算网络在时空混沌系统上的应用，该系统模拟了湍流的若干特征。我们表明，使用径向基函数作为非线性投影器，即使只有部分观测并且不知道控制方程，也能稳健地捕捉复杂的系统非线性。最后，我们表明，当测量稀疏、不完整且带有噪声，甚至控制方程变得不准确时，我们的网络仍然可以产生相当准确的预测，从而为实际湍流系统的无模型预测铺平了道路。
Phase-plate transmission electron microscopy has recently regressed since a report that Volta phase-plate phase-contrast is less sensitive than non-phase-plate phase contrast, which leads to conventional defocusing phase-contrast. What about Hilbert phase-plate phase-contrast? We report that the Hilbert phase-plate method can survive if two experiments using a pair of symmetric Hilbert phase-plates, of which phase is set to a value smaller than π, are combined. Three phase-contrast methods using the symmetric Hilbert phase-plates and Zernike phase-plate representing Volta phase-plate and Scherzer defocus respectively were compared in sensitivity theoretically relying on a contrast transfer theory and computationally on a simulator specifically designed for phase plate transmission electron microscopy. For the two phase-plate phase-contrasts, the phase that gives the highest sensitivity was searched for by changing the phase-plate phase. As a result, the symmetric Hilbert phase-plates phase-contrast was found to outperform Scherzer defocus phase-contrast in the phase around π/2. On the other hand, Zernike phase-plate phase-contrast was found considerably inferior to Scherzer defocus phase-contrast in the entire phase range from 0 to π. Furthermore, the novel Hilbert phase-plate method was compared with complex observation transmission electron microscopy, which also requires two experiments, and the origin of the higher sensitivity of symmetric Hilbert phase-plates phase-contrast was examined.
