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- 摘要
- 关键词
- 实验方案
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[IEEE 2018 IEEE 16th Intl Conf on Dependable, Autonomic and Secure Computing, 16th Intl Conf on Pervasive Intelligence and Computing, 4th Intl Conf on Big Data Intelligence and Computing and Cyber Science and Technology Congress(DASC/PiCom/DataCom/CyberSciTech) - Athens, Greece (2018.8.12-2018.8.15)] 2018 IEEE 16th Intl Conf on Dependable, Autonomic and Secure Computing, 16th Intl Conf on Pervasive Intelligence and Computing, 4th Intl Conf on Big Data Intelligence and Computing and Cyber Science and Technology Congress(DASC/PiCom/DataCom/CyberSciTech) - Road Extraction from High-Resolution Remotely Sensed Image Based on Improved Ant Colony Optimization Method
摘要： Based on improved ant colony optimization method, this paper presents a new developed approach to extract road from high-resolution panchromatic remotely sensed image. The former original ant colony optimization is used to extract the road network and its detail information is not exact. This paper improved the deployment of ants and the heuristic function to extract the complete road information. With the guidance of the neighbor gray level, ants are deployed at the edge of the image and move forward for reaching the opposite side. As ants spread pheromone along their paths, roads can be extracted based on aggregated pheromone levels. This paper analyzed the practicality of this method by measuring the correctness and completeness of the extracted roads. The experimental results prove that the improved ant colony optimization method can improve the quality of the extracted roads by raising the road’s correctness and retaining the road’s completeness.
关键词： ant colony optimization,pheromone,high-resolution remotely sensed image,road extraction
更新于2025-09-11 14:15:04
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Visual, aberrometric, photic phenomena, and patient satisfaction after myopic wavefront-guided LASIK using a high-resolution aberrometer
摘要： The purpose of this study was to evaluate the visual, refractive, and aberrometric outcomes as well as the level of patient satisfaction and photic phenomena after myopic laser in situ keratomileusis (LASIK) surgery using wavefront-guided (WFG) ablations based on measurements obtained with a high-resolution aberrometer. This study was a prospective analysis including 253 eyes of 127 patients (aged between 19 years and 54 years) undergoing WFG LASIK using the STAR S4 IR Excimer Laser System combined with the iDesign System and iFS Femtosecond Laser. Visual, refractive, and aberrometric outcomes during a 2-month follow-up as well as patient satisfaction and photic phenomena were evaluated by means of a questionnaire. A total of 85% (215/253) and 99% (251/253) of eyes achieved a postoperative (Postop) uncorrected distance visual acuity of 20/16 and 20/20, respectively, and all eyes achieved an uncorrected distance visual acuity of 20/25. Postop spherical equivalent values were within ±0.25 D and ±0.50 D in 97% and 100% of eyes, respectively. Likewise, manifest cylinder was <0.25 D in 97% (245/253) of eyes. A statistically significant reduction was found in the total root mean square (P<0.001) and in the level of primary spherical aberration (P=0.001). Postop difficulties related to vision were graded as minimal, with low levels of photic phenomena and high levels of patient satisfaction. The level of difficulty to perform daily activities and the level of glare perceived by patients while driving car were significantly decreased (P<0.001). WFG LASIK surgery using the technology evaluated is predictable and effective for the correction of myopia and leads to high levels of patient satisfaction.
关键词： Wave-front guided LASIK,patient satisfaction,glare,LASIK,high resolution aberrometer,photic phenomena
更新于2025-09-11 14:15:04
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A Long-Term Historical Aerosol Optical Depth Data Record (1982-2011) Over China From AVHRR
摘要： A long-term historical aerosol optical depth (AOD) data (15–45° N; 75–135° E) with 0.1 spatial resolution has been produced from Advanced Very High Resolution Radiometer (AVHRR) Pathfinder Atmospheres—Extended level-2B data. The spatial distribution pattern shows that high AOD values are found in central and eastern China over the entire period with AODs larger in summer and spring than in autumn and winter. As the high-quality products from AERONET were absent for this period over mainland China, AOD data obtained using the broadband extinction method from solar radiation stations have been used to verify the quality of the AVHRR AOD data set over China. The intercomparison results show that the interannual variation of AOD has been well captured in the variation curve of the AOD monthly mean and the variation trend is also consistent over the whole period. The correlation coefficient of the monthly mean is mostly larger than 0.55, the agreement index is larger than 0.57, and the relative error is less than 21%. Both AVHRR and visibility data sets show high values in regions with rapid economic development. Using Moderate Resolution Imaging Spectroradiometer AOD data as references, it is found that AVHRR AOD from this paper has better accuracy in general than that from Deep Blue (DB) algorithm over China, especially over eastern and southern China, while DB provides more coverage especially over bright surface such as northwest China. This long-term historic AOD data set can be used together with other AOD data sets to study the climate and environmental changes, especially in the 1980s and 1990s.
关键词： Aerosol optical depth (AOD),Advanced Very High Resolution Radiometer (AVHRR),solar radiation,multiple regression method,Moderate Resolution Imaging Spectroradiometer (MODIS)
更新于2025-09-10 09:29:36
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Optimized image acquisition for dopamine transporter imaging with ultra-high resolution clinical pinhole SPECT
摘要： SPECT can be used to image dopamine transporter (DaT) availability in the human striatum, e.g. for diagnosis of Parkinson’s disease (PD). As traditional SPECT provides limited resolution and sensitivity, we proposed a full ring focusing multi-pinhole SPECT system (G-SPECT-I (Beekman 2015 Eur. J. Nucl. Med. Mol. Imaging 42 S209)) which demonstrated a 2.5 mm reconstructed resolution in phantom scans. G-SPECT-I achieves data completeness in the scan region of interest by translating the patient bed with an xyz-stage and combining projections from all bed positions into image reconstruction using a scanning focus method (SFM). This paper aims to develop dedicated SFM parameters for performing a DaTscan with high effective sensitivity and appropriate sampling. To this end, the axial scanning length was restricted and transaxial bed trajectories with a reduced number of positions based on a convex hull data-completeness model were tested. Quantitative accuracy was assessed using full G-SPECT-I simulations of an Alderson phantom based on measured system matrices. For each sampling strategy, the specific binding ratio (SBR) and asymmetry index (AI) in the left and right striatum, as well as the Localized SBR (L-SBR) and the Localized AI (L-AI) in eight striatal sub-regions were calculated and compared to those of the reference scan which performs full brain oversampling using 112 bed positions. Results show that structures essential for PD diagnosis were visually and quantitatively barely affected even when using the lowest number of bed translations (i.e. 4). The maximum deviation from the reference was only 1.5%, 1.5%, 5.5% and 7.0% for the SBR, AI, L-SBR and L-AI, respectively, when 4 positions were used. Thus, it is possible to perform an accurate DaTscan with a confined axial scan region and a limited number of focused bed positions. This enables protocols for extremely fast dynamic SPECT scans with less than half-minute time frames, which can be useful for motion correction.
关键词： sampling,pinhole collimator,brain imaging,high resolution SPECT,DaTscan,high sensitivity SPECT,clinical SPECT
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 Improved CFAR Scheme for Man-Made Target Detection in High Resolution SAR Images
摘要： CFAR is a widely used algorithm for target detection in SAR images. The simplicity of computation and stable performance make it a key role in practice. However, for man-made target detection, conventional CFAR has a limited performance because of the non-adaptive processing window and the varieties of categories, sizes and structures of targets. In order to detect man-made targets with different size and complex structures in high resolution SAR images, an improved CFAR algorithm with an adaptive processing window named Adaptive-Window CFAR is proposed. A global guard window obtained by pre-detection adaptively is used to take place of the guard window in conventional CFAR makes AW-CFAR an algorithm with both adaptive threshold and adaptive processing window. In this case, the size of detectable targets is not fixed anymore and targets of different sizes and complex structures are detectable in AW-CFAR. Images with different resolutions and environments, which contain different categories of man-made targets, are used in the experiments. The experimental results show that the AW-CFAR inherits the simplicity of computation and stable performance of the conventional CFAR and has a better performance of man-made target detection in high resolution SAR images.
关键词： high resolution SAR image,global guard window,CFAR,adaptive processing window,man-made target detection
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 (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - End-to-End Learning of Polygons for Remote Sensing Image Classification
摘要： While geographic information systems typically use polygonal representations to map Earth's objects, most state-of-the-art methods produce maps by performing pixelwise classification of remote sensing images, then vectorizing the outputs. This paper studies if one can learn to directly output a vectorial semantic labeling of the image. We here cast a mapping problem as a polygon prediction task, and propose a deep learning approach which predicts vertices of the polygons outlining objects of interest. Experimental results on the Solar photovoltaic array location dataset show that the proposed network succeeds in learning to regress polygon coordinates, yielding directly vectorial map outputs.
关键词： convolutional neural networks,vectorial,polygon,regression,deep learning,High-resolution aerial images
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 - Exploiting Nonlocal Filters for High-Resolution Insar Dem Generation
摘要： Nonlocal filters show outstanding performance in the field of interferometric phase restoration by providing strong filtering power together with high spatial features preservation. In this work we focus on the generation of Digital Elevation Models (DEM) from a pair of interferometric SAR images. In the specific, we aim at comparing the performance of state-of-the-art InSAR filtering approaches on the basis of their noise suppression and detail preservation capabilities. We exploit a dataset of TanDEM-X SAR data relative to the volcanic area of the Kamchatka region (Russia).
关键词： InSAR,Interferometry,High-resolution Digital Elevation Model,Nonlocal filter
更新于2025-09-10 09:29:36
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High-resolution analysis of the 12.6?μm spectral region of the nitryl chloride ClNO2 molecule
摘要： The 12.6 μm region of nitryl chloride (ClNO2) has been recorded at high resolution (0.00102 cm?1) using a Fourier transform spectrometer and the SOLEIL synchrotron light source. ClNO2 was found during our studies of chlorine nitrate and, after fractional distillations it was introduced into a multipass White cell made of inert materials, with an optical path length of 5.4 m. 320 scans were recorded for the range 600–980 cm?1 at a total pressure of 0.23 hPa and a temperature of 250 K. A thorough analysis of the ν2, 2ν6 and 2ν3 bands of 35ClNO2 falling in this region has been carried out using a Hamiltonian model which takes explicitly into account the numerous resonances affecting the ro-vibrational energy levels; especially the C-type Coriolis resonance between the ν2 and the ν3 + ν6 modes. These two modes are only separated by less than 20 cm?1 and are thoroughly mixed. From the fittings, the following band centers were derived: νo(ν2) = 792.761264(60) cm?1, νo(ν3 + ν6) = 775.8923(20) cm?1 for 35ClNO2 where the uncertainties are one standard deviation. Due to their sharp Q branches falling into an atmospheric “window”, the detection of the ν2 bands might be an advantageous route for future attempts to quantify atmospheric ClNO2, using infrared techniques.
关键词： Nitryl chloride,Line positions,Coriolis and Fermi resonances,ClNO2,High-resolution fourier transform spectroscopy
更新于2025-09-10 09:29:36
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Highly sensitive detection of photo-thermal transient stress by a sub-nanosecond pump probe with surface plasmon resonance
摘要： Photoacoustic microscopy (PAM) has attracted increasing attention for non-invasive functional imaging in biomedicine and biomedical studies. The surface plasmon resonance (SPR) sensor is a potential acoustical detector with high sensitivity and wide bandwidth for use in high-resolution 3D PAM. In this study, we investigated a simple Kretschmann SPR sensor, demonstrating highly sensitive stress detection in the sub-nanosecond timescale by directly inducing photo-thermal transient stress. To do this, we designed and used a sub-nanosecond pump probe system. The SPR sensor clearly detected the transient response from the thermal elastic effect, while a simple pump-probe sensor without SPR did not detect it. Our experimental results demonstrate a simple SPR sensor that can detect stress with high sensitivity and sub-nanosecond time resolution. This technique could be used in high-resolution 3D PAM by mounting a small biomedical sample on the sensor.
关键词： photoacoustic microscopy,sub-nanosecond pump probe,surface plasmon resonance,photo-thermal transient stress,high-resolution 3D imaging
更新于2025-09-10 09:29:36
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High-resolution speckle imaging
摘要： One of the most exciting and challenging pursuits of 21st-century astrophysics is to identify an exoplanet—that is, a planet orbiting an alien sun—on which life may exist. Such a planet is likely to reside in the habitable zone of its sun, meaning that it can harbor liquid water on its surface. Many astrobiologists posit that a life-harboring planet must also be small, rocky, and similar in density to our own. One critical input to any future discovery will be a precise determination of the planet radius, a value that will probably be obtained with the help of high-resolution speckle imaging.
关键词： speckle imaging,exoplanet,adaptive optics,atmospheric turbulence,high-resolution imaging
更新于2025-09-10 09:29:36