- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Demonstration of complementarity between path information and interference with thermal light
摘要： We report an experimental demonstration of complementarity between path information and interference in second-order correlation with thermal light. The key apparatus is a Sagnac interferometer in which an off-axis slit is inserted. Two orthogonal thermal light beams travel through the slit clockwise and anticlockwise in the interferometer. The second-order interference fringes vanish when the path information is acquired. The interference fringes are revived when the path information is effaced.
关键词： path information,second-order correlation,thermal light,Sagnac interferometer,complementarity,interference
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - A New Registration Algorithm for Multimodal Remote Sensing Images
摘要： Automatic registration of remote sensing images is a challenging problem in the applications of remote sensing. The multimodal remote sensing images have significant nonlinear radiometric differences, which lead to the failure of area-based and feature-based registration methods. In this paper, to overcome significant nonlinear radiometric differences and large scale differences of multimodal remote sensing images, we propose a new registration algorithm, which can meet the need of initial registration of multimodal remote sensing images that conform to similarity transformation model. Our synthetic and real-data experimental results demonstrate the effectiveness and good performance of the proposed method in terms of visualization and registration accuracy.
关键词： multi-scale atlas,phase correlation,Log-Gabor filter,Multimodal remote sensing images,image registration
更新于2025-09-23 15:22:29
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Sparse Reconstruction-Based Thermal Imaging for Defect Detection
摘要： This paper proposes an idea of employing sparse reconstruction-based technique for thermal imaging defect detection. The implementation of the reconstruction technique is tested on a carbon fiber reinforced polymer test piece with artificially drilled defects and the test results are compared with the established cross correlation method. The two processes are compared in terms of defect detectability, their SNR variation with defect depth and their computation complexity. When compared with cross correlation algorithm, the technique is expected to solve memory space problems by compressing all information from large cross-correlated pulse video into a single reconstructed image as an output. Furthermore, in existing cross correlation methods, the pulse peak time shifts with defect depth. Hence, defect quantification algorithms, such as SNR calculation, require multiple frame analysis. Such algorithms are comparatively simplified in sparse reconstruction technique. This paper explores sparse reconstruction algorithm for resolving close-spaced defects. This paper further describes cross-validation method for optimization of a user parameter in sparse reconstruction method.
关键词： thermal nondestructive testing,sparse reconstruction,pulse compression,nondestructive evaluation and remote sensing,frequency modulated thermal wave imaging,Cross correlation algorithm
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE 3rd International Conference on Image, Vision and Computing (ICIVC) - Chongqing (2018.6.27-2018.6.29)] 2018 IEEE 3rd International Conference on Image, Vision and Computing (ICIVC) - Distributed Compressive Video Sensing with Adaptive Reconstruction Based on Temporal Correlation
摘要： Aiming at enhance reconstruction quality, this paper proposes an adaptive reconstruction scheme with no feedback channel for distributed compressive video sensing, effectively exploiting temporal correlation. Specifically, the proposed scheme divides each block of non-key frames into different classifications based on temporal correlation in the encoding side and selects corresponding reconstruction mode which adaptively utilizes side information in the decoding side. The simulation results show that the proposed scheme achieves superior performance over existing methods in terms of reconstruction quality and computation cost.
关键词： adaptive reconstruction,distributed compressive video sensing,temporal correlation
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Efficient Registration for InSAR Large-Scale Image Using Quadtree Segmentation
摘要： In this paper, an efficient registration algorithm for InSAR large scale image via discrete Fourier transform (DFT) model of the maximum correlation and image quadtree segmentation is proposed. In the scheme, a DFT-based sub-pixel registration model of InSAR complex images is constructed. Then, efficient sub-pixel registration for InSAR large-scale image is achieved by joint quadtree segmentation and DFT-based interpolation registration. Simulation and experimental results are presented to confirm the effectiveness of the proposed algorithm. The results demonstrate that the algorithm not only can achieve sub-pixel registration of InSAR large-scale image, but also has higher computational efficiency compared with the traditional maximum correlation registration method.
关键词： quadtree segmentation,maximum correlation,InSAR,large-scale image,image registration
更新于2025-09-23 15:22:29
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[IEEE 2018 China International SAR Symposium (CISS) - Shanghai (2018.10.10-2018.10.12)] 2018 China International SAR Symposium (CISS) - Range-Variant Channel Errors Calibration Algorithm for Multichannel HRWS SAR Imaging
摘要： Azimuth multichannel SAR system can realize high-resolution and wide-swath (HRWS) SAR imaging, which has attracted interests. The azimuth ambiguities of multichannel SAR can be suppressed by digital beamforming (DBF) techniques. However, the presence of inevitable channel errors deteriorates the performance of ambiguity suppression. In this paper, we focus on the research of range-variant channel phase errors. We analyze the effect of radial position errors by using the second order Taylor series to expand the azimuth phase history. It indicates that the radial position errors can be regarded as range-variant phase errors. We divide the raw data into several blocks along range direction. Then we use the azimuth cross-correlation technique to estimate the phase errors of each block data. Compared with the subspace-based calibration techniques, the azimuth cross-correlation technique does not use the information of azimuth ambiguities. Afterwards, the fitting process is employed to estimate the range-variant channel phase errors. Finally, the experiments on real data processing validate the effectiveness of our proposed method.
关键词： channel error calibration,Range-variant,HRWS,cross-correlation,multichannel SAR
更新于2025-09-23 15:22:29
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Displacement Measurement Errors in Digital Image Correlation Due to Displacement Mapping Function
摘要： In the classic subset-based local digital image correlation (DIC) technique, the displacement measurement errors due to the displacement mapping function have been an important factor to improve the measurement accuracy. In general, the first-order displacement mapping function is broadly used. But, in the real experiments, the order of the deformation of the test sample is higher than that of the used displacement mapping function. So the errors due to the undermatched displacement mapping functions are existent. Although the random errors due to the overmatched shape function have been studied, the root-mean square errors (RMSEs) due to the matched or mismatched displacement mapping function are not studied. In this paper, the RMSEs of the measured displacements due to the matched or mismatched displacement mapping function are investigated experimentally by employing the simulated and real experimental speckle patterns. Moreover, the relationships between the RMSE and the subset size or the image noise are thoroughly examined. Finally, the practical implementation of DIC is recommended in terms of the subset size and the image noise.
关键词： Shape function,Error,Digital image correlation,Undermatched,Displacement,Displacement mapping function
更新于2025-09-23 15:22:29
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Object Tracking Algorithm Based on Dual Color Feature Fusion with Dimension Reduction
摘要： Aiming at the problem of poor robustness and the low effectiveness of target tracking in complex scenes by using single color features, an object-tracking algorithm based on dual color feature fusion via dimension reduction is proposed, according to the Correlation Filter (CF)-based tracking framework. First, Color Name (CN) feature and Color Histogram (CH) feature extraction are respectively performed on the input image, and then the template and the candidate region are correlated by the CF-based methods, and the CH response and CN response of the target region are obtained, respectively. A self-adaptive feature fusion strategy is proposed to linearly fuse the CH response and the CN response to obtain a dual color feature response with global color distribution information and main color information. Finally, the position of the target is estimated, based on the fused response map, with the maximum of the fused response map corresponding to the estimated target position. The proposed method is based on fusion in the framework of the Staple algorithm, and dimension reduction by Principal Component Analysis (PCA) on the scale; the complexity of the algorithm is reduced, and the tracking performance is further improved. Experimental results on quantitative and qualitative evaluations on challenging benchmark sequences show that the proposed algorithm has better tracking accuracy and robustness than other state-of-the-art tracking algorithms in complex scenarios.
关键词： self-adaptive feature fusion,principal component analysis,feature fusion,correlation filter,visual tracking
更新于2025-09-23 15:22:29
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A spatiotemporal probabilistic model-based temperature-augmented probabilistic load flow considering PV generations
摘要： The probabilistic steady‐state forecasting of a PV‐integrated power system requires a suitable forecasting model capable of accurately characterizing the uncertainties and correlations among multivariate inputs. The critical and foremost difficulties in the development of such a model include the accurate representation of the characterizing features such as complex nonstationary pattern, non‐Gaussianity, and spatial and temporal correlations. This paper aims at developing an improved high‐dimensional multivariate spatiotemporal model through enhanced preprocessing, transformation techniques, principal component analysis, and a suitable time series model that is capable of accurately modeling the trend in the variance of uncertain inputs. The proposed model is applied to the probabilistic load flow carried out on the modified Indian utility 62‐bus transmission system using temperature‐augmented system model for an operational planning study. A detailed discussion of various results has indicated the effectiveness of the proposed model in capturing the aforesaid characterizing features of uncertain inputs.
关键词： PV generation,probabilistic load flow,operational planning,spatiotemporal correlation,steady‐state forecasting
更新于2025-09-23 15:22:29
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Assessment of Fringe Pattern Decomposition with a Cross-Correlation Index for Phase Retrieval in Fringe Projection 3D Measurements
摘要： Phase retrieval from single frame projection fringe patterns, a fundamental and challenging problem in fringe projection measurement, attracts wide attention and various new methods have emerged to address this challenge. Many phase retrieval methods are based on the decomposition of fringe patterns into a background part and a fringe part, and then the phase is obtained from the decomposed fringe part. However, the decomposition results are subject to the selection of model parameters, which is usually performed manually by trial and error due to the lack of decomposition assessment rules under a no ground truth data situation. In this paper, we propose a cross-correlation index to assess the decomposition and phase retrieval results without the need of ground truth data. The feasibility of the proposed metric is verified by simulated and real fringe patterns with the well-known Fourier transform method and recently proposed Shearlet transform method. This work contributes to the automatic phase retrieval and three-dimensional (3D) measurement with less human intervention, and can be potentially employed in other fields such as phase retrieval in digital holography.
关键词： parameter selection,cross-correlation,Fourier transform,phase retrieval,Shearlet transform,fringe pattern decomposition
更新于2025-09-23 15:21:21