- 标题
- 摘要
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- 实验方案
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Region-Based Co-Seismic Ground Displacement Dectection Using Optical Aerial Imagery
摘要： Ground analysis is important after an earthquake occurred in order to understand the surface variations. By optical imagery before and after a disaster, this paper tries to find the co-seismic ground displacement using region-based image patches. By comparing the similarity of pre- and post-event orthophotos, regions of ground changes can be detected. Conjugate objects were then recognized through feature extraction and image matching. An image with pose parameters can estimate the three-dimensional positions of those objects in the world space. Thus, three-dimensional geometric correlation between the pre- and post-event objects can measure the ground displacement. The results indicate that the proposed approach is able to estimate the co-seismic ground displacements based on the spatial information from optical imagery. In addition, surface shifts can be identified based on the spatial correlations.
关键词： spatial correlation,Image similarity,ground variation,image matching
更新于2025-09-10 09:29:36
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Spaceborne Repeat-pass Interferometric Synthetic Aperture Radar Experimental Evaluation for the GaoFen-3 Satellite
摘要： High-precision DEM can be generated by SAR interferometry processing with GaoFen-3 repeat-pass data.This paper presents the first results from GaoFen-3 SAR Interferometry obtained with two interferometric SAR data pairs at the selected experiment sites. The temporal separations were 29 days. At the site the coherence requirements were met, resulting in high quality interferogram .The experimental results show that GaoFen-3 repeat-pass data have some good characteristics, such as high imaging quality, stable spatial baseline, high temporal correlation and spatial correlation, which has a good repeat-pass SAR interferometry application prospect.
关键词： SAR Interferometry,correlation,Repeat-pass,DEM,GaoFen-3
更新于2025-09-10 09:29:36
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - An Adaptive Region-Based Method for Speckle Reduction in SAR Images with Local Geometric Correlation
摘要： For adaptive region-based despeckling methods, the shape of the adaptive region is of large influence on the estimation of the true value. In this paper, given the effectiveness of patch-based index on measuring the relativity of samples, an adaptive region is formed at each pixel via the patch-based index where the local geometric correlation (such as the anisotropy and the compactness) among the pixels in the patch is explored as an Adaptive Kernel (AK) function. Then, using all pixels contained in the adaptive region, Maximum likelihood rule is adopted to estimate the true value of the concerned pixel. From the experimental results on real and synthetic SAR images, by using the AK function embedded patchy index to determine the adaptive region, not only the speckle is largely reduced, but also the resolution of the details is well preserved by our method.
关键词： adaptive region,patch-based index,local geometric correlation,speckle reduction,SAR imagery
更新于2025-09-10 09:29:36
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Correlation-Based Variational Change Detection for Elevation Models
摘要： In this study, we propose a correlation based variational change detection (CVCD) method for elevation models. In essence, CVCD aims to produce smooth change maps while preserving the details of the terrain by minimizing a variational cost function. Proposed cost function is constructed with a novel data fidelity term using normalized correlation coefficient and (cid:96)1-norm total variation regularization term. An effective algorithm is suggested to minimize the cost function using simple approximations in an iterative method. Quantitative experiments on synthetic noisy data show that CVCD can provide a detection rate of 95% while staying in the low false alarm regime, i.e. less than 10?2. Also, qualitative experiments on real-world data show the success of the CVCD for the changes with different characteristics.
关键词： normalized cross correlation,digital elevation model,change detection,sparsity
更新于2025-09-10 09:29:36
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Change Detection in Optical Remote Sensing Images with a Fully Object-Level Approach
摘要： In this paper, an efficient and accurate multilevel change detection method is presented, achieved by the combination of an unsupervised object-based correlation analysis and a supervised post-classification comparison. Before the change detection procedure, fast multitemporal segmentation is applied to provide object-level information on two registered images. Then the proposed object-based correlation analysis method is used to extract the potential changed areas efficiently and stably, which improves the accuracy of overall performance. Notably, all the procedures are highly automatic except for the necessary selection of training examples within all supervised algorithms. The experimental results demonstrate the superior performance of our method compared with the four typical state-of-the-art change detection methods.
关键词： fast multitemporal segmentation,object-based correlation analysis,change detection,post-classification comparison
更新于2025-09-10 09:29:36
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A sensor detecting kissing bonds in adhesively bonded joints using electric time domain reflectometry
摘要： The joining technology with the highest potential in lightweight construction is the adhesive bonding. In an adhesively bonded joint different defects can occur. Alongside gross defects like areas of uncured adhesive and voids, adhesion defects like kissing bonds pose a serious problem to the confidence in these kind of joints in the aircraft industry and other industries. Since kissing bonds are small interfacial defects of as few as nanometers in thickness, the detection by conventional nondestructive testing methods is not possible in most applications. In this paper a novel adhesive sensor based on the electric time domain reflectometry is proposed detecting differences in the deformation of the adherents in an adhesively bonded joint to infer that a kissing bond is taking affect. Numerical calculations are used to show that the proposed sensor principle poses a productive approach. For the numerical calculations a finite difference time domain model is used. The sensor is then validated experimentally by shear tension testing of single lap shear specimens with the adhesive sensor integrated into the joint.
关键词： Kissing bond,Fiber reinforced plastics,Digital image correlation,Non-destructive testing,Adhesively bonded joint,Electric time domain reflectometry
更新于2025-09-10 09:29:36
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Pulse Compressed Time Domain Multiplexed Fiber Bragg Grating Sensor: A Comparative Study
摘要： This paper experimentally demonstrates the feasibility of improving the sensing performance of fiber Bragg grating (FBG)-based point sensors by deploying two pulse coding techniques, simplex coding (SSC), and Golay complementary codes (GCC). The two techniques are separately combined with the conventional time-domain multiplexed FBG (TDM-FBG) interrogation sensor, and their results are compared with respect to the conventional single pulse interrogation technique. Consistently with the theory, for both the coding techniques, we have confirmed that the signal-to-noise ratio improved proportionally to the code length. In details, for both the techniques, the signal-to-noise improvement ratio of two FBGs located after around 16.35 km of fiber has significantly increased up to about 6 dB. Furthermore, the decoded signals from both techniques conserve their original spatial properties, confirming the successfulness of Hadamard transform and Golay auto-correlation calculations. Our experimental analysis confirms the simplex codes with their significant noise reduction ability, which is translated into well formed and accurate mean amplitude calculations. Moreover, the analysis of TDM-FBG-based GCCs have confirmed the unique properties of the auto-correlation process to increase the FBG signals up to around 128 times compared with the single pulse case.
关键词： simplex pulse coding,Hadamard transform,TDM-FBG,auto-correlation,SSC,Golay complementary codes (GCC),signal-to-noise-ratio,Noise reduction
更新于2025-09-10 09:29:36
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EXPRESS: Two-Dimensional Correlation Spectroscopy (2D-COS) for Analysis of Spatially Resolved Vibrational Spectra
摘要： The last two decades have seen tremendous progress in the application of two-dimensional correlation spectroscopy (2D-COS) as a versatile analysis method for data series obtained by a large variety of different spectroscopic modalities, including infrared (IR) and Raman spectroscopy. The analysis technique is applicable to a series of spectra recorded under the influence of an external sample perturbation. 2D-COS analysis is not only helpful to decipher correlations which may exist between distinct spectral features, but can be utilized also to obtain the sequence of individual spectral changes. The focus of this review article is on the application of 2D-COS for analyzing spatially resolved data with special emphasis on hyperspectral imaging (HSI) study. In this review, we briefly introduce the fundamentals of the generalized 2D-COS analysis approach, discuss specific points of 2D-COS application to spatially resolved spectra and demonstrate essential aspects of data pre-processing for 2D-COS analysis of spatially resolved spectra. Based on illustrative examples we show that 2D-COS is useful for spectral band assignment in HSI applications and demonstrate its utility for detecting subtle correlations between spectra features, or between features from different imaging modalities in the case of heterospectral (multimodal) HSI. Furthermore, a short overview on existing 2D-COS software tools is provided. It is hoped that this article represents not only a useful guideline for 2D-COS analyses of spatially resolved hyperspectral data but supports also further dissemination of the 2D-COS analysis method as a whole.
关键词： Spatially Resolved Vibrational Microspectroscopy,Multimodal Imaging,Two-Dimensional Correlation Spectroscopy (2D-COS),Hyperspectral Imaging
更新于2025-09-10 09:29:36
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The Repeatability of Retinal Layer Thickness Measurements with Spectral-Domain Optical Coherence Tomography in Normal Eyes
摘要： Purpose: To evaluate the repeatability of retinal layer thickness measurements in normal eyes imaged using spectral domain optical coherence tomography (SD-OCT). Methods: Sixty-eight eyes of 34 healthy subjects were enrolled in this study. Imaging was performed 4 times using 9 × 9 mm macular scans with SD-OCT (RS 3000 Advance HD OCT, NIDEK, Gamagori, Japan) at the same visit by an experienced examiner. After automatic retinal segmentation (layering) in 5 layers, the thickness of each layer was calculated. Macular thickness of 9 Early Treatment of Diabetic Retinopathy Study (ETDRS)–like regions was obtained. Repeatability for each of the 9 subfield areas was calculated by their repeatability coefficients and intraclass correlation coefficients (ICCs). Results: There was no significant difference in average retinal thickness and each retinal layer thickness between all measurements acquired by the experienced examiner. The ICCs of retinal layer thickness ranged from 0.826 to 0.847 for the ganglion cell layer + inner plexiform layer, inner nuclear layer + outer plexiform layer and outer nuclear layer + external limiting membrane in the fovea. The ICCs were greater than 0.909 for the other intra-retinal layers in all 9 ETDRS subfield thickness between all measurement pairs. Conclusions: Excellent repeatability was observed for SD-OCT retinal segmented layer thickness measurements in healthy subjects.
关键词： Repeatability,Spectral domain optical coherence tomography,Retinal layer thickness,Automated segmentation,Intraclass correlation coefficients
更新于2025-09-10 09:29:36
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Intraspectrum Discrimination and Interspectrum Correlation Analysis Deep Network for Multispectral Face Recognition
摘要： Multispectral images contain rich recognition information since the multispectral camera can reveal information that is not visible to the human eye or to the conventional RGB camera. Due to this characteristic of multispectral images, multispectral face recognition has attracted lots of research interest. Although some multispectral face recognition methods have been presented in the last decade, how to fully and effectively explore the intraspectrum discriminant information and the useful interspectrum correlation information in multispectral face images for recognition has not been well studied. To boost the performance of multispectral face recognition, we propose an intraspectrum discrimination and interspectrum correlation analysis deep network (IDICN) approach. Multiple spectra are divided into several spectrum-sets, with each containing a group of spectra within a small spectral range. The IDICN network contains a set of spectrum-set-specific deep convolutional neural networks attempting to extract spectrum-set-specific features, followed by a spectrum pooling layer, whose target is to select a group of spectra with favorable discriminative abilities adaptively. IDICN jointly learns the nonlinear representations of the selected spectra, such that the intraspectrum Fisher loss and the interspectrum discriminant correlation are minimized. Experiments on the well-known Hong Kong Polytechnic University, Carnegie Mellon University, and the University of Western Australia multispectral face datasets demonstrate the superior performance of the proposed approach over several state-of-the-art methods.
关键词： multispectral face recognition,spectra selection,useful interspectrum correlation information exploration,Deep convolutional neural networks (DCNNs),intraspectrum discriminant information exploration
更新于2025-09-10 09:29:36