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Wavelet Analysis of Space Solar Telescope Images 被引量:2
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作者 Xi-AnZhu Sheng-ZhenJin +1 位作者 Jing-YuWang Shu-NianNing 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2003年第6期587-596,共10页
The scientific satellite SST (Space Solar Telescope) is an important research project strongly supported by the Chinese Academy of Sciences. Every day, SST acquires 50 GB of data (after processing) but only 10GB can b... The scientific satellite SST (Space Solar Telescope) is an important research project strongly supported by the Chinese Academy of Sciences. Every day, SST acquires 50 GB of data (after processing) but only 10GB can be transmitted to the ground because of limited time of satellite passage and limited channel volume. Therefore, the data must be compressed before transmission. Wavelets analysis is a new technique developed over the last 10 years, with great potential of application. We start with a brief introduction to the essential principles of wavelet analysis, and then describe the main idea of embedded zerotree wavelet coding, used for compressing the SST images. The results show that this coding is adequate for the job. 展开更多
关键词 stars: images - techniques: image processing - methods: wavelet analysis
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Example-based super-resolution for single-image analysis from the Chang'e-1 Mission
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作者 Fan-Lu Wu Xiang-Jun Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第11期57-60,共4页
Due to the low spatial resolution of images taken from the Chang'e-1 (CE-I) orbiter, the details of the lunar surface are blurred and lost. Considering the limited spatial resolution of image data obtained by a CCD... Due to the low spatial resolution of images taken from the Chang'e-1 (CE-I) orbiter, the details of the lunar surface are blurred and lost. Considering the limited spatial resolution of image data obtained by a CCD camera on CE-1, an example-based super-resolution (SR) algorithm is employed to obtain high- resolution (HR) images. SR reconstruction is important for the application of image data to increase the resolution of images. In this article, a novel example-based algorithm is proposed to implement SR reconstruction by single-image analysis, and the computational cost is reduced compared to other example-based SR methods. The results show that this method can enhance the resolution of images using SR and recover detailed information about the lunar surface. Thus it can be used for surveying HR terrain and geological features. Moreover, the algorithm is significant for the HR processing of remotely sensed images obtained by other imaging systems. 展开更多
关键词 Moon - methods: data analysis - techniques: image processing
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Analysis of the geomorphology surrounding the Chang'e-3 landing site 被引量:6
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作者 Chun-Lai Li Ling-Li Mu +8 位作者 Xiao-Duan Zou Jian-Jun Liu Xin Ren Xing-Guo Zeng Yi-Man Yang Zhou-Bin Zhang Yu-Xuan Liu Wei Zuo Han Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1514-1529,共16页
Chang'e-3 (CE-3) landed on the Mare Imbrium basin in the east part of Sinus Iridum (19.51°W, 44.12°N), which was China's first soft landing on the Moon and it started collecting data on the lunar surfa... Chang'e-3 (CE-3) landed on the Mare Imbrium basin in the east part of Sinus Iridum (19.51°W, 44.12°N), which was China's first soft landing on the Moon and it started collecting data on the lunar surface environment. To better understand the environment of this region, this paper utilizes the available high-resolution topography data, image data and geological data to carry out a detailed analysis and research on the area surrounding the landing site (Sinus Iridum and 45 km×70 km of the landing area) as well as on the topography, landform, geology and lunar dust of the area surrounding the landing site. A general topographic analysis of the surrounding area is based on a digital elevation model and digital elevation model data acquired by Chang'e-2 that have high resolution; the geology analysis is based on lunar geological data published by USGS; the study on topographic factors and distribution of craters and rocks in the surrounding area covering 4km^4km or even smaller is based on images from the CE-3 landing camera and images from the topographic camera; an analysis is done of the effect of the CE-3 engine plume on the lunar surface by comparing images before and after the landing using data from the landing camera. A comprehensive analysis of the results shows that the landing site and its surrounding area are identified as typical lunar mare with flat topography. They are suitable for maneuvers by the rover, and are rich in geological phenomena and scientific targets, making it an ideal site for exploration. 展开更多
关键词 atlases -- methods: data analysis -- techniques: image processing --techniques: photometric
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Reconstructing the landing trajectory of the CE-3 lunar probe by using images from the landing camera 被引量:3
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作者 Jian-Jun Liu Wei Yan +3 位作者 Chun-Lai Li Xu Tan Xin Ren Ling-Li Mu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1530-1542,共13页
An accurate determination of the landing trajectory of Chang'e-3 (CE-3) is significant for verifying orbital control strategy, optimizing orbital planning, accu- rately determining the landing site of CE-3 and anal... An accurate determination of the landing trajectory of Chang'e-3 (CE-3) is significant for verifying orbital control strategy, optimizing orbital planning, accu- rately determining the landing site of CE-3 and analyzing the geological background of the landing site. Due to complexities involved in the landing process, there are some differences between the planned trajectory and the actual trajectory of CE-3. The land- ing camera on CE-3 recorded a sequence of the landing process with a frequency of 10 frames per second. These images recorded by the landing camera and high-resolution images of the lunar surface are utilized to calculate the position of the probe, so as to reconstruct its precise trajectory. This paper proposes using the method of trajectory reconstruction by Single Image Space Resection to make a detailed study of the hov- ering stage at a height of 100 m above the lunar surface. Analysis of the data shows that the closer CE-3 came to the lunar surface, the higher the spatial resolution of im- ages that were acquired became, and the more accurately the horizontal and vertical position of CE-3 could be determined. The horizontal and vertical accuracies were 7.09 m and 4.27 m respectively during the hovering stage at a height of 100.02 m. The reconstructed trajectory can reflect the change in CE-3's position during the powered descent process. A slight movement in CE-3 during the hovering stage is also clearly demonstrated. These results will provide a basis for analysis of orbit control strategy, and it will be conducive to adjustment and optimization of orbit control strategy in follow-up missions. 展开更多
关键词 Moon - methods: data analysis - techniques: image processing
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A new segmentation algorithm for lunar surface terrain based on CCD images 被引量:2
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作者 Hong-Kun Jiang Xiao-Lin Tian Ao-Ao Xu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第9期1604-1612,共9页
Terrain classification is one of the critical steps used in lunar geomorphologic analysis and landing site selection. Most of the published works have focused on a Digital Elevation Model (DEM) to distinguish differ... Terrain classification is one of the critical steps used in lunar geomorphologic analysis and landing site selection. Most of the published works have focused on a Digital Elevation Model (DEM) to distinguish different regions of lunar terrain. This paper presents an algorithm that can be applied to lunar CCD images by blocking and clustering according to image features, which can accurately distinguish between lunar highland and lunar mare. The new algorithm, compared with the traditional algo- rithm, can improve classification accuracy. The new algorithm incorporates two new features and one Tamura texture feature. The new features are generating an enhanced image histogram and modeling the properties of light reflection, which can represent the geological characteristics based on CCD gray level images. These features are ap- plied to identify texture in order to perform image clustering and segmentation by a weighted Euclidean distance to distinguish between lunar mare and lunar highlands. The new algorithm has been tested on Chang'e-1 CCD data and the testing result has been compared with geological data published by the U.S. Geological Survey. The result has shown that the algorithm can effectively distinguish the lunar mare from highlands in CCD images. The overall accuracy of the proposed algorithm is satisfactory, and the Kappa coefficient is 0.802, which is higher than the result of combining the DEM with CCD images. 展开更多
关键词 Moon -- methods: data analysis -- techniques: image processing
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A new lunar absolute control point: established by images from the landing camera on Chang'e-3 被引量:1
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作者 Fen-Fei Wang Jian-Jun Liu +9 位作者 Chun-Lai Li Xin Ren Ling-Li Mu Wei Yan Wen-Rui Wang Jing-Tao Xiao Xu Tan Xiao-Xia Zhang Xiao-Duan Zou Xing-Ye Gao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1543-1556,共14页
The establishment of a lunar control network is one of the core tasks in selenodesy, in which defining an absolute control point on the Moon is the most im- portant step. However, up to now, the number of absolute con... The establishment of a lunar control network is one of the core tasks in selenodesy, in which defining an absolute control point on the Moon is the most im- portant step. However, up to now, the number of absolute control points has been very sparse. These absolute control points have mainly been lunar laser ranging retrore- flectors, whose geographical location can be observed by observations on Earth and also identified in high resolution lunar satellite images. The Chang'e-3 (CE-3) probe successfully landed on the Moon, and its geographical location has been monitored by an observing station on Earth. Since its positional accuracy is expected to reach the meter level, the CE-3 landing site can become a new high precision absolute control point. We use a sequence of images taken from the landing camera, as well as satellite images taken by CE-1 and CE-2, to identify the location of the CE-3 lander. With its geographical location known, the CE-3 landing site can be established as a new abso- lute control point, which will effectively expand the current area of the lunar absolute control network by 22%, and can greatly facilitate future research in the field of lunar surveying and mapping, as well as selenodesy. 展开更多
关键词 Moon -- methods: data analysis -- techniques: image processing
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Automated removal of stripe interference in full-disk solar images
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作者 Sheng Zheng Shuan He +2 位作者 Yao Huang Hui-Ling He Gang-Hua Lin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第6期13-20,共8页
The quality of full-disk solar Hα images is significantly degraded by stripe interference. In this paper, to improve the analysis of morphological evolution, a robust solution for stripe interference removal in a par... The quality of full-disk solar Hα images is significantly degraded by stripe interference. In this paper, to improve the analysis of morphological evolution, a robust solution for stripe interference removal in a partial full-disk solar Hα image is proposed. The full-disk solar image is decomposed into a set of support value images on different scales by convolving the image with a sequence of multiscale support value filters, which are calculated from the mapped least-squares support vector machines (LS-SVMs). To match the resolution of the support value images, a scale-adaptive LS-SVM regression model is used to remove stripe interference from the support value images. We have demonstrated the advantages of our method on solar Hα images taken in 2001-2002 at the Huairou Solar Observing Station. Our experimental results show that our method can remove the stripe interference well in solar Hα images and the restored image can be used in morphology researches. 展开更多
关键词 methods: data analysis -- techniques: image processing -- Sun: general
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Fast compression and reconstruction of astronomical images based on compressed sensing
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作者 Wang-Ping Zhou Yang Li +2 位作者 Qing-Shan Liu Guo-Dong Wang Yuan Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第9期1207-1214,共8页
With the fast increase in the resolution of astronomical images, the question of how to process and transfer such large images has become a key issue in astronomy. We propose a new real-time compression and fast recon... With the fast increase in the resolution of astronomical images, the question of how to process and transfer such large images has become a key issue in astronomy. We propose a new real-time compression and fast reconstruction algorithm for astronomical images based on compressive sensing techniques. We first reconstruct tile Original signal with fewer measurements, according to its compressibility. Then, based on the characteristics of astronomical images, we apply Daubechies orthogonal wavelets to obtain a sparse representation. A matrix representing a random Fourier ensembleis used to obtain a sparse representation in a lower dimensional space. For reconstructing the image, we propose a novel minimum total variation with block addptive sensing to balance the accuracy and eomputation time. Our experimental results show that the proposed algorithm can efficiently reconstruct colorful astronomicai images with high resolution and improve the applicability of compressed sensing. 展开更多
关键词 methods: data analysis -- methods: numerical -- techniques: image processing
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Calpain mediated cisplatin-induced ototoxicity in mice 被引量:6
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作者 Liang Chang Aimei Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第21期1995-2002,共8页
Ototoxic drug-induced apoptosis of inner ear cells has been shown to be associated with calpain expression. Cisplatin has severe ototoxicity, and can induce cochlear cell apoptosis. This study assumed that cisplatin a... Ototoxic drug-induced apoptosis of inner ear cells has been shown to be associated with calpain expression. Cisplatin has severe ototoxicity, and can induce cochlear cell apoptosis. This study assumed that cisplatin activated calpain expression in apoptotic cochlear cells. A mouse model of cisplatin-induced ototoxicity was established by intraperitoneal injection with cisplatin (2.5, 3.5, 4.5, 5.5 mg/kg). Immunofluorescence staining, image analysis and western blotting were used to detect the expression of calpain 1 and calpain 2 in the mouse cochlea. At the same time, the auditory brainstem response was measured to observe the change in hearing. Results revealed that after intraperitoneal injection with cisplatin for 5 days, the auditory brainstem response threshold shifts increased in mice. Calpain 1 and calpain 2 expression significantly increased in outer hair cells, the spiral ganglion and stria vascularis. Calpain 2 protein expression markedly increased with an increased dose of cisplatin. Results suggested that calpain 1 and calpain 2 mediated cisplatin-induced ototoxicity in BALB/c mice. During this process, calpain 2 plays a leading role. 展开更多
关键词 neural regeneration biological factor CISPLATIN MICE COCHLEA apoptosis CALPAIN auditory brainstem response OTOTOXICITY immunofluorescence staining image analysis technique western blotting grants-supported paper neuroregeneration
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A method and results of color calibration for the Chang'e-3 terrain camera and panoramic camera 被引量:6
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作者 Xin Ren Chun-Lai Li +5 位作者 Jian-Jun Liu Fen-Fei Wang Jian-Feng Yang En-Hai Liu Bin Xue Ru-Jin Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1557-1566,共10页
The terrain camera (TCAM) and panoramic camera (PCAM) are two of the major scientific payloads installed on the lander and rover of the Chang'e 3 mission re- spectively. They both use a Bayer color filter array c... The terrain camera (TCAM) and panoramic camera (PCAM) are two of the major scientific payloads installed on the lander and rover of the Chang'e 3 mission re- spectively. They both use a Bayer color filter array covering CMOS sensor to capture color images of the Moon's surface. RGB values of the original images are related to these two kinds of cameras. There is an obvious color difference compared with human visual perception. This paper follows standards published by the International Commission on Illumination to establish a color correction model, designs the ground calibration experiment and obtains the color correction coefficient. The image qual- ity has been significantly improved and there is no obvious color difference in the corrected images. Ground experimental results show that: (1) Compared with uncor- rected images, the average color difference of TCAM is 4.30, which has been reduced by 62.1%. (2) The average color differences of the left and right cameras in PCAM are 4.14 and 4.16, which have been reduced by 68.3% and 67.6% respectively. 展开更多
关键词 Moon -- methods: data analysis -- techniques: image processing
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Preliminary results of solving the problem of geometric distortion for the 2.4 m telescope at Yunnan Observatory 被引量:3
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作者 Qing-Feng Zhang Qing-Yu Peng Zi Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第10期1451-1456,共6页
We observed the open clusters NGC 1664 (43 exposures) and M35 (42 ex- posures) by the Yunnan Faint Object Spectrograph and Camera in the 2.4 m telescope at Yunnan Astronomical Observatory on 2011 January 3, and pr... We observed the open clusters NGC 1664 (43 exposures) and M35 (42 ex- posures) by the Yunnan Faint Object Spectrograph and Camera in the 2.4 m telescope at Yunnan Astronomical Observatory on 2011 January 3, and processed them by a method recently proposed by us. The result shows that there is a geometric distortion effect in the field of view and the maximum distortion is - 0.25 (i.e. 1 pixel). After correcting the geometric distortion, the precision of stellar positional measurement is significantly improved. The best precision in each direction is 6 mas for well-exposed stars. 展开更多
关键词 astrometry -- methods: data analysis -- techniques: image processing
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A solar radio dynamic spectrograph with flexible temporal-spectral resolution 被引量:2
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作者 Qing-Fu Du Lei Chen +7 位作者 Yue-Chang Zhao Xin Li Yan Zhou Jun-Rui Zhang Fa-Bao Yan Shi-Wei Feng Chuan-Yang Li Yao Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第9期111-118,共8页
Observation and research on solar radio emission have unique scientific values in solar and space physics and related space weather forecasting applications, since the observed spectral structures may carry important ... Observation and research on solar radio emission have unique scientific values in solar and space physics and related space weather forecasting applications, since the observed spectral structures may carry important information about energetic electrons and underlying physical mechanisms. In this study, we present the design of a novel dynamic spectrograph that has been installed at the Chashan Solar Radio Observatory operated by the Laboratory for Radio Technologies, Institute of Space Sciences at Shandong University. The spectrograph is characterized by real-time storage of digitized radio intensity data in the time domain and its capability to perform off-line spectral analysis of the radio spectra. The analog signals received via antennas and amplified with a low-noise amplifier are converted into digital data at a speed reaching up to 32 k data points per millisecond. The digital data are then saved into a high- speed electronic disk for further off-line spectral analysis. Using different word lengths (1-32k) and time cadences (5 ms-10 s) for off-line fast Fourier transform analysis, we can obtain the dynamic spectrum of a radio burst with different (user-defined) temporal (5 ms-10 s) and spectral (3 kHz-320kHz) resolutions. This enables great flexibility and convenience in data analysis of solar radio bursts, especially when some specific fine spectral structures are under study. 展开更多
关键词 Sun: radio radiation-- radiation: dynamics-- instrumentation: spectrographs-- methods data analysis -- techniques: image processing
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THE QUANTITATIVE MEASUREMENT OF BCL-2, P53 PROTEIN AND PCNA EXPRESSION IN BREAST CARCINOMA AND THEIR CORRELATION WITH PROGNOSIS
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作者 张学斌 王鸿雁 《Journal of Pharmaceutical Analysis》 CAS 1998年第2期120-124,132,共6页
To study quantitative index of bci-2, P53, Nroliferating cell nuclear antigen (PCNA),ER and PR in breast carcinoma and their correiation and their relatiousbip with prognosis, the ex expression of bcl-2, P53 and PCNA ... To study quantitative index of bci-2, P53, Nroliferating cell nuclear antigen (PCNA),ER and PR in breast carcinoma and their correiation and their relatiousbip with prognosis, the ex expression of bcl-2, P53 and PCNA were studied by immunohistochemical technique. The measurementof ER and PR used enzyme linked affinuity histochemical methods. The quantitative index was analyzed by image technique. All analyses were hased on 60 breast carcinomas. The results were as follows:the more bcl-2 protein, the lower histological graded the longer survival term and the highersurvival rate (P< 0. 05). The quautitative measurement of bcl-2, P53 and PCNA expression were ofvalue in evaluating the degree of differentiation and prognosis in breast carcinoma. The quantitativeand qualitative measurement or p53 protein expression showed a Ⅰwerful evidence in evaluatingprognosis of bcl-2 were more significant in evaluating poor prognosis of breast carcinoma. A relationship between bcl-2 and ER, PR showed a better value for response to endocrine therapy in breastcarcinoma patients. 展开更多
关键词 breast carcinoma P53 protein bcl-2 protein PCNA image analysis technique
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