- 标题
- 摘要
- 关键词
- 实验方案
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Multimodal hard x-ray imaging with resolution approaching 10 nm for studies in material science
摘要： We report multimodal scanning hard x-ray imaging with spatial resolution approaching 10 nm and its application to contemporary studies in the field of material science. The high spatial resolution is achieved by focusing hard x-rays with two crossed multilayer Laue lenses and raster-scanning a sample with respect to the nanofocusing optics. Various techniques are used to characterize and verify the achieved focus size and imaging resolution. The multimodal imaging is realized by utilizing simultaneously absorption-, phase-, and fluorescence-contrast mechanisms. The combination of high spatial resolution and multimodal imaging enables a comprehensive study of a sample on a very fine length scale. In this work, the unique multimodal imaging capability was used to investigate a mixed ionic-electronic conducting ceramic-based membrane material employed in solid oxide fuel cells and membrane separations (compound of Ce0.8Gd0.2O2?x and CoFe2O4) which revealed the existence of an emergent material phase and quantified the chemical complexity at the nanoscale.
关键词： mixed ionic-electronic conducting membrane,x-ray nanoscale imaging,multimodal imaging,high spatial resolution
更新于2025-09-23 15:23:52
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Object-based automatic multi-index built-up areas extraction method for WorldView-2 satellite imagery
摘要： In this study, an object-based automatic multi-index BUs extraction method was developed. First, several indices, including built-up areas extraction index (NBEIr-c), vegetation extraction index(NDVInir2-r) and water extraction index (NDWI b-nir1), were developed to obtain the BUs, vegetation and water maps, and then the fractional-order Darwinian particle swarm optimization (FODPSO) algorithm was employed to automatically segment the multi-index images and obtained BUs, water, vegetation and BS information. Finally, the extracted BUs results were optimized via an object-based analysis method and the results were compared with those of two other relevant indices, which confirmed the proposed indices had a higher accuracy and exhibited higher performance when separating the BS from the BUs.
关键词： Built-up areas,Object-based,Multi-index,Worldview-2,High spatial resolution images
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE MTT-S International Wireless Symposium (IWS) - Guangzhou, China (2019.5.19-2019.5.22)] 2019 IEEE MTT-S International Wireless Symposium (IWS) - A Dual-Mode Dual-Band Waveguide Filter Excited by Coaxial Probe
摘要： In this paper, we discuss the scienti?c outcomes of the 2015 data fusion contest organized by the Image Analysis and Data Fusion Technical Committee (IADF TC) of the IEEE Geoscience and Remote Sensing Society (IEEE GRSS). As for previous years, the IADF TC organized a data fusion contest aiming at fostering new ideas and solutions for multisource studies. The 2015 edition of the contest proposed a multiresolution and multisensorial challenge involving extremely high-resolution RGB images and a three-dimensional (3-D) LiDAR point cloud. The competition was framed in two parallel tracks, considering 2-D and 3-D products, respectively. In this paper, we discuss the scienti?c results obtained by the winners of the 2-D contest, which studied either the complementarity of RGB and LiDAR with deep neural networks (winning team) or provided a comprehensive benchmarking evaluation of new classi?cation strategies for extremely high-resolution multimodal data (runner-up team). The data and the previously undisclosed ground truth will remain available for the community and can be obtained at http://www.grss-ieee.org/community/technical-committees/data-fusion/2015-ieee-grss-data-fusion-contest/. The 3-D part of the contest is discussed in the Part-B paper [1].
关键词： image analysis and data fusion (IADF),multiresolution-,landcover classification,multimodal-data fusion,multisource-,Deep neural networks,extremely high spatial resolution,LiDAR
更新于2025-09-19 17:13:59
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400 Gb/s Silicon Photonic Transmitter and Routing WDM technologies for glueless 8-socket Chip-to-Chip interconnects
摘要： A novel frequency-based classification framework and new wavelet algorithm (Wave-CLASS) is proposed using an overcomplete decomposition procedure. This approach omits the downsampling procedure and produces four-texture information with the same dimension of the original image or window at infinite scale. Three image subsets of QuickBird data (i.e., park, commercial, and rural) over a central region in the city of Phoenix were used to examine the effectiveness of the new wavelet overcomplete algorithm in comparison with a widely used classical approach (i.e., maximum likelihood). While the maximum-likelihood classifier produced < 78.29% overall accuracies for all three image subsets, the Wave-CLASS algorithm achieved high overall accuracies—95.05% for the commercial subset (Kappa = 0.94), 93.71% for the park subset (Kappa = 0.93), and 89.33% for the rural subset (Kappa = 0.86). Results from this study demonstrate that the proposed method is effective in identifying detailed urban land cover types in high spatial resolution data.
关键词： overcomplete decomposition,high spatial resolution,infinite scale,urban land cover,Classification,wavelet transforms
更新于2025-09-16 10:30:52
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Assessing the infinitely expanding intersection region for the development of large-scale multipoint laser Doppler velocimetry
摘要： Multipoint laser Doppler velocimetry (MLDV) has been effective for non-invasively measuring the flow velocity distribution with a high-spatial and high-time resolution. The flow velocity can be estimated using a scattered light signal by seeding particles passing through a fringe pattern formed in the intersection region of two laser beams. The shape of this intersection region can be easily changed by changing the optical components and positions of the lasers. An infinitely expanding intersection region is proposed in the present paper. A wide intersection region was indicated by the measurement results of flow velocity. The intersection region is evaluated using a flow channel (1.4 mm ? 1.4 mm). The area of the operating measurement region exceeds 150 mm in the horizontal direction and is less than ?10 mm in the vertical direction. This new MLDV is referred to as a large-scale MLDV.
关键词： flow velocity distribution,high-spatial resolution,large-scale MLDV,intersection region,high-time resolution,Multipoint laser Doppler velocimetry,MLDV
更新于2025-09-12 10:27:22
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[IEEE 2019 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) - Auckland, New Zealand (2019.5.20-2019.5.23)] 2019 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) - High-Spatial Resolution Demodulation of Weak FBGs Based on Incoherent Optical Frequency Domain Reflectometry Using a Chaotic laser
摘要： A high-spatial resolution demodulation technique based on incoherent optical frequency domain reflectometry is proposed for distributed weak fiber Bragg grating (FBG) sensing. A single longitudinal mode, narrow linewidth light output from Distributed Feedback Laser (DFB) is modulated with a frequency swept microwave, then enter the FBGs and reflected. The reflected optical signal is transformed into electric signal by a photodiode, and then mixes with the original microwave to produce the beat frequency. We can use Fast Fourier transformation to analyze the beat frequency to modulate the location information, next control the wavelength of DFB laser to sweep in a specific range and finally obtain the wavelength information of FBGs. In order to eliminate the influence of interference between light reflected from the FBGs, chaotic signals from DFB laser with optical feedback are generated to broaden the linewidth of laser. Therefore, the spatial resolution of FBGs can be greatly improved to 10cm. and we have demonstrated the long distance demodulation nearly 500m and 10cm interval with the achieved accuracy to be 16 pm.
关键词： high-spatial resolution,chaotic laser,narrow linewidth,Incoherent Optical Frequency Domain Reflection
更新于2025-09-12 10:27:22
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Scanning laser terahertz near-field reflection imaging system
摘要： We developed a scanning laser terahertz (THz) near-field reflection imaging system using a fiber-coupled femtosecond laser source for high spatial resolution measurements without any sub-wavelength probes. In this system, THz wave pulses generated at the laser focusing spot in a non-linear optical crystal interact with a sample set on the crystal. Using this system, we obtained the THz reflection images of metallic structures with a resolution of ～λTHz/34 (λTHz = 680 μm) and also observed paraffin-embedded human breast tissue of several 10 μm in size. These results promise that this system can be suitable for industrial applications which require micron-scale resolution.
关键词： near-field,terahertz,reflection imaging,femtosecond laser,high spatial resolution
更新于2025-09-12 10:27:22
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Knowledge-Based Identification and Damage Detection of Bridges Spanning Water via High-Spatial-Resolution Optical Remotely Sensed Imagery
摘要： Bridges over water are important artificial objects that can be damaged by natural disasters. Accurate identification and damage detection of such bridges through the use of high-spatial-resolution optical remotely sensed imagery are important in emergency rescue and lifeline safety assessment. In this study, we detail a knowledge-based method of identification and damage detection of bridges spanning water using high-spatial-resolution optical remotely sensed imagery. Data on the body of water are extracted to define spatial extent and improve the timeliness of identification and damage detection, the threshold values of the rectangle degree and area are set to remove false bridge targets, and the damaged parts are detected according to the bridge’s rectangular characteristics and the relationship with the body of water. First, the characteristics, such as spectral, geometric, and textural, and spatial relationships of the bridge over water, are analyzed. Second, to limit the spatial extent of bridge identification and improve computational efficiency, data on the body of water are extracted. Third, the post-event bridge is identified from the viewpoint of bridge integrity based on shape and area parameters. Damage detection is then performed according to the bridge’s integrity. Finally, the results are evaluated for both non-positional and positional accuracy. Results of experiments carried out in Huiyang and Wenchuan, China, show that the proposed method, using high-spatial-resolution optical remotely sensed imagery, is effective for identification and damage detection of fallen and collapsed bridges spanning water. Therefore, the method is useful in updating the geographic database of bridges and assessing damage to them caused by natural disasters.
关键词： Bridges spanning water,High-spatial-resolution optical remotely sensed imagery,Feature knowledge,Feature analysis,Identification and damage detection
更新于2025-09-12 10:27:22
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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 - Tree Crown Detection and Delineation Using Optical Satellite Imagery
摘要： Automated individual tree crown detection and delineation (ITCD) is essential for forest mapping, sustainable urban planning and 3D city model. In this paper, ITCD using high-resolution optical Worldview-2 satellite imagery over Singapore is presented. The object-based multiresolution approach for tree mapping including tree positions, crown sizes and canopy gaps is described. Accuracy assessment is performed with ground truth data.
关键词： tree crown detection,tree crown,object based method,high spatial resolution,canopy
更新于2025-09-10 09:29:36
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Variable location channels to improve efficiency and precision for direct ? <i>T</i> <sub/><i>e</i> </sub> measurements and high spatial resolution <i>T</i> <sub/><i>e</i> </sub> -profile measurements using electron cyclotron emission
摘要： Electron cyclotron emission (ECE) diagnostics that use variable location channels based on yttrium iron garnet (YIG) bandpass filters improve the precision and the efficiency of measurements of electron temperature (Te) profiles and fluctuations (δTe). These variable frequency filters were substituted for fixed frequency filters in the intermediate frequency section to achieve the required higher resolution over a target radial range, just before the experiment. Here, we present the proof-of-principle for high temporal resolution measurement of the electron temperature gradient, via real-time slewing of a YIG filter for relocation of an ECE channel during a long pulse. The key component is the application of YIG tunable filters with their narrow bandwidth and capability for a high slew rate of their center frequency. This application permits fast relocation of the ECE channels for direct measurement of the gradient and close spacing of channels to investigate the magnetic island’s dynamic behavior.
关键词： Electron cyclotron emission,YIG bandpass filters,electron temperature gradient,high spatial resolution
更新于2025-09-10 09:29:36