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Additionally, we apply the proposed method to four publicly available datasets, and the results show that our methods may be helpful for the detection and analysis of retinopathy.The Scheimpflug measurement system has broad application prospects in the fields of tomographic particle image velocimetry (PIV), ophthalmology, and three-dimensional reconstruction. Additionally, its special imaging structure makes the theoretical model of other traditional calibration methods no longer applicable. A cross-point calibration method in which the real-world coordinate system is transferred from an in-kind calibrator to displacement, achieving great improvements in the quantity and accuracy of the feature points, is proposed. This method, which makes up for the defects introduced by the distorted imaging plane, also in turn simplifies the calibration process. Finally, the proposed method is tested via both simulation and calibration experiments. The high calibration accuracy verifies that the method is feasible.An efficient scheme for a microwave (MW) receiver is proposed based on the active Raman gain (ARG) in Rydberg atoms. The 87Rb atoms are excited to the Rydberg state (53D5/2), and the gain spectrum has a single gain peak. The MW field is resonant with the Rydberg transition (53D5/2→54P3/2), resulting in a split in the gain spectrum. The frequency splitting of two peaks depends linearly on the MW field strength. The distortion and attenuation of the probe field are reduced, due to the system's operating in the stimulated Raman emission mode. Simulation results show that the fidelity of MW communication based on the Rydberg atomic ARG scheme is improved by at least 10 times compared to that based on an electromagnetically induced transparency scheme, and the system seems more robust to amplitude modulation signals with different modulation depths.In this study, we design a Cassegrain-based concentrator with tailored mirrors. The proposed concentrator comprises a primary optical element (POE) and a secondary optical element (SOE). The POE is a parabolic concave mirror and the SOE is a hyperbolic convex mirror. In order to achieve uniform irradiance distribution without a homogenizer, the POE is tailored and tilted to generate a uniform distribution by overlapping the energy well. The Cassegrain-based concentrator with tailored mirrors can achieve a geometric concentration ratio of 1236×, a concentration ratio of 1034×, an optical efficiency of 83.66%, an acceptance angle of ±0.38∘, a uniformity of 7.87, and an aspect ratio of 0.254.When the scatterer size is less than 100 wavelengths, the effect of diffraction is large. The analysis of diffraction is important for 3D shape measurement. However, in soft x rays, shapes suitable for rigorous diffraction analysis have been limited to ellipses and periodic structures. We have developed a method to expand this to any shape (isolated triangle, rectangle, etc.). Experimentally, we measured the respective widths of the cross section of a column consisting of two layers and showed that the resolution was at least a few wavelengths. For this purpose, we have also developed a fast simulation method with a small memory size.As a measurement system that can realize target detection and optical imaging, the accuracy of three-dimensional laser radar is a main performance index, which makes calibration an extremely important work. Traditional calibration methods have many disadvantages, such as harsh environment requirements, complex and tedious calibration processes, and inaccurate calibration results. To solve these problems, we propose a calibration method so that the relative position of the cooperative target and the detection sensor is fixed. The principle of space-time transform is used to simulate distance, and the synchronous control of distance is realized by controlling the delay module. In addition, a simple and practical calibration device is designed. In the actual measurement, the average absolute error is 0.0019 m, and the relative error is 0.0678% in the range of 0.5-25 m. The experimental results show that this method is stable and accurate, and it can calibrate the plane array laser radar quickly and accurately.An image interpolation model based on sparse representation is proposed. Two widely used priors including sparsity and nonlocal self-similarity are used as the regularization terms to boost the performance of the interpolation model. Meanwhile, we incorporate nonlocal linear regression into this model, since nonlocal similar patches could provide a better approximation to a given patch. selleck Moreover, we propose a new approach to learn an adaptive sub-dictionary online instead of clustering. For each patch, similar patches are grouped to learn the adaptive sub-dictionary, generating a more sparse and accurate representation. Finally, weighted encoding is introduced to suppress tailing of fitting residuals in data fidelity. Abundant experimental results show that our proposed method achieves better performance compared to several state-of-the-art methods in terms of subjective and objective evaluations.The quantitative analyses of pH value in soil have been performed using laser-induced breakdown spectroscopy (LIBS) technology. The aim of this work was to obtain a reliable and accurate method for rapid detection of pH value in soil. Seventy-four samples were used as a calibration set, and 24 samples were used as a prediction set. To eliminate the matrix effect, the multivariate models of partial least-squares regression (PLSR) and least-squares support vector regression (LS-SVR) were used to construct the models. The intensities of nine emission lines of C, Ca, Na, O, H, Mg, Al, and Fe elements were used to fit the models. For the PLSR model, the correlation coefficient was 0.897 and 0.906 for the calibration and prediction set, respectively. Furthermore, the analysis accuracy was improved effectively by the LS-SVR method, and the correlation coefficients for calibration and prediction set were improved to 0.991 and 0.987. The prediction mean absolute error was pH 0.1 units, and the root mean square error of the prediction was only 0.