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Impact of three different processing methods on the digestibility and allergenicity of Chinese mitten crab(Eriocheir sinensis)tropomyosin
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作者 Yufeng Lu Huafeng Cheng +2 位作者 Shaotong Jiang Lin Lin Jianfeng Lu 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期903-911,共9页
The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.The... The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.Therefore,in this study,the effects of three different processing methods,i.e.,microwave,ultrasound,and high temperature-pressure(HTP)treatments,on the digestion stability of TM from Chinese mitten crab muscle and the allergenicity of TM digestion products were explored.sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that microwaving had little effect on the digestion stability of TM.In contrast,ultrasound and HTP treatments facilitated the degradation of TM.Similarly,Western blotting and inhibition ELISA indicated that the IgE-binding activity of TM was significantly reduced after treatment with ultrasound or HTP.Among the three different proces sing methods,HTP was the most effective method for improving digestibility of TM and reducing immunoreactivity.This finding provides new insights into treatments for crab allergies. 展开更多
关键词 Chinese mitten crab TROPOMYOSIN Processing methods IMMUNOREACTIVITY
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Impact of Selected Processing Methods of High-Level Cyanide in Cassava on Optic Neuropathy in Wistar Albino Rats—An Experimental Study
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作者 Azubuike Alfred Onua Stephen Itopa Musa 《Open Journal of Ophthalmology》 2023年第1期172-185,共14页
Background: Cassava tuber crop is a staple food rich in carbohydrates and utilized in various forms by millions of Nigerians. The storage root of the cassava contains linamarin, a cyanogenic glycoside that is easily h... Background: Cassava tuber crop is a staple food rich in carbohydrates and utilized in various forms by millions of Nigerians. The storage root of the cassava contains linamarin, a cyanogenic glycoside that is easily hydrolyzed to release cyanide salt compounds which is toxic to the nervous system especially the optic nerve, sometimes leading to optic neuropathy and visual impairment. Aim: The aim of this study is to find out the impact of selected processing methods of high-level cyanide in cassava on optic neuropathy in Wistar albino rats. Methodology: Twenty-four Wistar albino rats were fed with different concentration and duration of predetermined high-cyanide content cassava root cultivar which was processed using different processing methods adopted by various communities in Rivers State, Nigeria (for human consumption). A control group of 3 Wistar albino rats was fed with normal “Growth Mesh” meals. The pre and post weights of the animals and the fundoscopic optic nerve status of the rats were evaluated after 30 and 60 days. SPSS Version 25 was employed for descriptive and inferential statistical analyses. A p-value of ≤0.05 was considered statistically significant. Results: The Cassava species available in Rivers State have high cyanide content (2336.79 mg CN<sup>-</sup>/kg dry weight of cassava). There was statistically significant reduction in the cyanide content (p = 0.000) depending on the various common processing methods (into garri for human consumption): 24 hours, 48 hours, fermentation;with and without red palm oil additive. The individual weights as well as the mean weight of the 24 rats in the experimental group increased gradually from the first week to the 9<sup>th</sup> week with a slight weight reduction on the third and fourth weeks which was not statistically significant (p = 0.092). However, there was a steady increase in the weights of the animals in the control group throughout the 9 weeks. Varying degrees of optic neuropathy occurred, worse with the rats that had 24-hour fermented cassava twice daily for 60 days. The intra and inter group differences in the optic disc changes was statistically significant (p = 0.000). Conclusion: Longer duration of processing cassava roots into garri for human consumption reduces its cyanide content and minimizes the adverse impact on the optic nerve. 展开更多
关键词 Cassava Processing methods Cyanide in Cassava Optic Neuropathy Wistar Albino Rats
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Effects of different processing methods on the lipid composition of hazelnut oil:a lipidomics analysis 被引量:2
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作者 Jiayang Sun Xiaonuo Feng +2 位作者 Chunmao Lyu Shuang Zhou Zixuan Liu 《Food Science and Human Wellness》 SCIE 2022年第2期427-435,共9页
Although hazelnut oil is rich in nutrients,its quality is greatly affected by how it is processed.However,no studies to date have comprehensively analyzed the lipid composition of hazelnut oil using different processi... Although hazelnut oil is rich in nutrients,its quality is greatly affected by how it is processed.However,no studies to date have comprehensively analyzed the lipid composition of hazelnut oil using different processing methods.Here,we conducted a lipidomics analysis using UPLC-QTOF-MS to characterize the lipid composition of cold-pressed hazelnut oil(CPO),ultrasonic-assisted hexane hazelnut oil(UHO)and enzyme-assisted aqueous hazelnut oil(EAO).A total of 10 subclasses of 98 lipids were identified,including35 glycerolipids(GLs),56 glycerophospholipids(GPs)and 7 sphingolipids(SPs).The total lipid and GL content were the highest in CPO,GP content was the highest in UHO and the ceramide content in SPs was most abundant in EAO.Multivariate statistical analysis showed that the lipid profiles of hazelnut oil prepared with different processing methods varied.Twelve significantly different lipids(TAG 54:3,TAG 52:2,TAG54:4,TAG 54:2,TAG 52:3,TAG 54:5,DAG 36:2,DAG 36:4,DAG 36:3,PC 36:2,PA 36:2 and PE 36:3)were identified,and these lipids could potentially be used as biomarkers to distinguish between hazelnut oil subjected to different processing methods.Our results provide useful information for hazelnut oil applications and new insight into the effects of edible oil processing. 展开更多
关键词 LIPIDOMICS Hazelnut oil Processing method Lipid composition
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Review of Processing Methods of Jujube
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作者 Lianfang LI 《Medicinal Plant》 CAS 2021年第4期93-95,97,共4页
Historical evolution of jujube processing,recording situation of modern processing specifications of jujube,research status of processing methods of jujube at home in recent years,content analysis of main chemical com... Historical evolution of jujube processing,recording situation of modern processing specifications of jujube,research status of processing methods of jujube at home in recent years,content analysis of main chemical composition in jujube processed products,and impact of processing on chemical composition of jujube are reviewed,which could provide basic data for fully studying,developing and utilizing jujube by scholars and technical staff. 展开更多
关键词 JUJUBE Processing method Chemical constituents
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信息型常见毒物质谱用户库的建立及其在毒物快速筛选上的应用研究 被引量:1
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作者 黎乾 戴维列 +5 位作者 温锦锋 邢若葵 王松才 张小婷 钟伟建 徐淑云 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期287-290,293,共5页
The spectrum user’s librarys containing 1533 familiar toxicants have been built; A method with high separability and sensitivity has been found,The RT and the detection limit of 210 familiar abuse drugs has been conf... The spectrum user’s librarys containing 1533 familiar toxicants have been built; A method with high separability and sensitivity has been found,The RT and the detection limit of 210 familiar abuse drugs has been confirmed; the processing methods to analyse spectrum data automatically have been found; It is simple,quick,sensitive and reliable,and can take place of manual operation,It is very useful to screen the familiar toxicants in unkown sample. 展开更多
关键词 Familiar toxicants abuse drugs DRUGS PESTICIDES Volatile toxicants Spectrum user’s library Spectrum data Processing method Screening
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Dietary energy sources and levels shift the multi-kingdom microbiota and functions in the rumen of lactating dairy cows 被引量:3
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作者 Tansol Park Lu Ma +3 位作者 Ying Ma Xiaoqiao Zhou Dengpan Bu Zhongtang Yu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第4期1073-1088,共16页
Background: Dietary energy source and level in lactation diets can profoundly affect milk yield and composition.Such dietary effects on lactation performance are underpinned by alteration of the rumen microbiota, of w... Background: Dietary energy source and level in lactation diets can profoundly affect milk yield and composition.Such dietary effects on lactation performance are underpinned by alteration of the rumen microbiota, of which bacteria, archaea, fungi, and protozoa may vary differently. However, few studies have examined all the four groups of rumen microbes. This study investigated the effect of both the level and source of dietary energy on rumen bacteria, archaea, fungi, and protozoa in the rumen of lactating dairy cows. A 2 × 2 factorial design resulted in four dietary treatments: low and high dietary energy levels(LE: 1.52–1.53;and HE: 1.71–1.72 Mcal/kg dry matter) and two dietary energy sources(GC: finely ground corn;and SFC: steam-flaked corn). We used a replicated 4 × 4 Latin square design using eight primiparous Chinese Holstein cows with each period lasting for 21 d. The rumen microbiota was analyzed using metataxonomics based on kingdom-specific phylogenetic markers [16 S r RNA gene for bacteria and archaea, 18 S r RNA gene for protozoa, and internally transcribed spacer 1(ITS1) for fungi] followed with subsequent functional prediction using PICRUSt2.Results: The GC resulted in a higher prokaryotic(bacterial and archaeal) species richness and Faith's phylogenetic diversity than SFC. For the eukaryotic(fungi and protozoa) microbiota, the LE diets led to significantly higher values of the above measurements than the HE diets. Among the major classified taxa, 23 genera across all the kingdoms differed in relative abundance between the two dietary energy levels, while only six genera(none being protozoal)were differentially abundant between the two energy sources. Based on prokaryotic amplicon sequence variants(ASVs) from all the samples, overall functional profiles predicted using PICRUSt2 differed significantly between LE and HE but not between the two energy sources. Fish Taco analysis identified Ruminococcus and Coprococcus as the taxa potentially contributing to the enriched KEGG pathways for biosynthesis of amino acids and to the metabolisms of pyruvate, glycerophospholipid, and nicotinate and nicotinamide in the rumen of HE-fed cows. The co-occurrence networks were also affected by the dietary treatments, especially the LE and GC diets, resulting in distinct co-occurrence networks. Several microbial genera appeared to be strongly correlated with one or more lactation traits.Conclusions: Dietary energy level affected the overall rumen multi-kingdom microbiota while little difference was noted between ground corn and steam-flaked corn. Some genera were also affected differently by the four dietary treatments, including genera that had been shown to be correlated with lactation performance or feed efficiency.The co-occurrence patterns among the genera exclusively found for each dietary treatment may suggest possible metabolic interactions specifically affected by the dietary treatment. Some of the major taxa were positively correlated to milk properties and may potentially serve as biomarkers of one or more lactation traits. 展开更多
关键词 Corn processing method Dietary energy level Functional profiles Multi-kingdom Rumen microbiota
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Effects of processing technology on essential oil and pharmacological action of frankincense 被引量:2
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作者 Xiang-Long Meng Yong-Lin Liang +4 位作者 Chen-Zi Lyu Xiao-Juan Su Cong Hu Chen-Xu Ning Shuo-Sheng Zhang 《Traditional Medicine Research》 2021年第3期16-36,共21页
Background:According to the traditional Chinese medicine theory,the common processing methods for Ruxiang(frankincense)include stir-frying processing and vinegar processing.Methods:With network pharmacology and therma... Background:According to the traditional Chinese medicine theory,the common processing methods for Ruxiang(frankincense)include stir-frying processing and vinegar processing.Methods:With network pharmacology and thermal analysis methods,we selected and identified the main and irritating ingredients,established the pyrolysis characteristic parameters for identifying frankincense quality,quantified the starting and optimum temperature limits for processing frankincense,and analyzed the influences of processing adjuvants(vinegar)on combustion pyrolysis characteristics of frankincense.By applying Fourier transformation infrared spectrometry,high performance liquid chromatography,gas chromatography and UV-visible spectrometry,we evaluated the processing technology developed in our study of frankincense and its processed products.Results:Based on network pharmacology,we can find that the classical compounds of essential oil are the main pharmacodynamics components of frankincense possessing the anti-inflammatory,analgesia,anti-tumor,anti-ulcer and ant-inflammatory bowel disease effects.The pyrolysis combustion rate peaks of frankincense at 285.27±7.05℃and 476.99±13.46℃were the characteristic peaks used to identify frankincense quality.The specific temperature of slow-fire processing,including the vinegar processing and stir-frying processing,was 148.72±5.09℃.Heating for 5.67±0.98 min after reaching processing temperature was needed for processing frankincense with vinegar.The kinetics analysis showed that both frankincense and its vinegar mixture exhibited good linear relationships.The feasibility and practicability for our processing technology were verified through the determination of medicinal compounds by Fourier transformation infrared spectrometry,high performance liquid chromatography,gas chromatography and UV.Conclusion:Frankincense essential oils were the main active components of frankincense,which also can be taken as the internal chemical control indexes to judge the quality control and to optimize the processing technology of frankincense.The pyrolysis combustion rate peaks of frankincense at 285.27±7.05℃and 476.99±13.46℃were the characteristic peaks that can be used to identify frankincense quality.The optimum processing conditions of vinegar-processed frankincense with were as follows:with vinegar,20%;heating temperature,148.72±5.09℃;and heating time,5.67±0.98 min.Under these conditions,frankincense essential oil could cause a moderate effect on combustion pyrolysis characteristics to exert its corresponding pharmacological effects. 展开更多
关键词 Frankincense Processing methods Vinegar processing Essential oil INFLAMMATORY Thermal gravimetric analysis
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Improvements of Traditional Laser Fraunhofer Diffraction Experiment Using Digital Image Processing Method 被引量:1
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作者 金远伟 王娅冰 +2 位作者 赵斌 伊兆广 许生慧 《Journal of Donghua University(English Edition)》 EI CAS 2020年第5期406-410,共5页
We present an improved digital image processing(DIP)method to calculate the widths of single slits.Different from the traditional laser Fraunhofer diffraction experiment in college physical experiments,by performing f... We present an improved digital image processing(DIP)method to calculate the widths of single slits.Different from the traditional laser Fraunhofer diffraction experiment in college physical experiments,by performing fast Fourier transform,inverse fast Fourier transform and the nonlinear leastsquare fitting on the diffraction pattern taken by a camera,the DIP method can quickly return an analytic expression,whose period is used to calculate widths of single slits.By comparing the measured results by the DIP method and the successional difference(SD)method,we find that for a single slit whose width is 60372μm,the DIP method is more accurate.Experimental results show that for single slits with widths between 40μm and 160μm,the relative error of the DIP method is less than 2.78%.Also,the DIP method can be used to measure the diameter of filament and fibres online in real time. 展开更多
关键词 digital image processing method traditional laser Fraunhofer diffraction experiment width of single slit
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An iterative wavefront sensing algorithm for high-contrast imaging systems 被引量:2
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作者 Jiang-Pei Dou 1,2,De-Qing Ren 1,2,3 and Yong-Tian Zhu 1,2 1 National Astronomical Observatories/Nanjing Institute of Astronomical Optics & Technology,Chinese Academy of Sciences,Nanjing 210042,China 2 Key Laboratory of Astronomical Optics & Technology,Nanjing Institute of Astronomical Optics & Technology,Chinese Academy of Sciences,Nanjing 210042,China 3 Physics & Astronomy Department,California State University Northridge,18111 Nordhoff Street,Northridge,California 91330-8268,USA 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第2期198-204,共7页
Wavefront sensing from multiple focal plane images is a promising technique for high-contrast imaging systems.However,the wavefront error of an optics system can be properly reconstructed only when it is very small.Th... Wavefront sensing from multiple focal plane images is a promising technique for high-contrast imaging systems.However,the wavefront error of an optics system can be properly reconstructed only when it is very small.This paper presents an iterative optimization algorithm for the direct measurement of large static wavefront errors from only one focal plane image.We first measure the intensity of the pupil image to get the pupil function of the system and acquire the aberrated image on the focal plane with a phase error that will be measured.Then we induce a dynamic phase on the tested pupil function and calculate the associated intensity of the reconstructed image on the focal plane.The algorithm will then try to minimize the intensity difference between the reconstructed image and the aberrated test image in the focal plane,where the induced phase is a variable of the optimization algorithm.The simulation shows that the wavefront of an optical system can theoretically be reconstructed with high precision,which indicates that such an iterative algorithm may be an effective way to perform wavefront sensing for high-contrast imaging systems. 展开更多
关键词 techniques: image processing -- methods numerical -- planetarysystems
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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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Data processing and initial results of Chang'e-3 lunar penetrating radar 被引量:10
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作者 Yan Su Guang-You Fang +8 位作者 Jian-Qing Feng Shu-Guo Xing Yi-Cai Ji Bin Zhou Yun-Ze Gao Han Li Shun Dai Yuan Xiao Chun-Lai Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1623-1632,共10页
To improve our understanding of the formation and evolution of the Moon, one of the payloads onboard the Chang'e-3 (CE-3) rover is Lunar Penetrating Radar (LPR). This investigation is the first attempt to explore... To improve our understanding of the formation and evolution of the Moon, one of the payloads onboard the Chang'e-3 (CE-3) rover is Lunar Penetrating Radar (LPR). This investigation is the first attempt to explore the lunar subsurface structure by using ground penetrating radar with high resolution. We have probed the subsur- face to a depth of several hundred meters using LPR. In-orbit testing, data processing and the preliminary results are presented. These observations have revealed the con- figuration of regolith where the thickness of regolith varies from about 4 m to 6 m. In addition, one layer of lunar rock, which is about 330 m deep and might have been accumulated during the depositional hiatus of mare basalts, was detected. 展开更多
关键词 space vehicles: instruments: Lunar Penetrating Radar -- techniques:radar astronomy -- methods data processing -- Moon: lunar subsurface -- Moon:regolith
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Data processing and initial results from the CE-3 Extreme Ultraviolet Camera 被引量:3
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作者 Jian-Qing Feng Jian-Jun Liu +10 位作者 Fei He Wei Yan Xin Ren Xu Tan Ling-Ping He Bo Chen Wei Zuo Wei-Bin Wen Yan Su Yong-Liao Zou Chun-Lai Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1664-1673,共10页
The Extreme Ultraviolet Camera (EUVC) onboard the Chang'e-3 (CE-3) lander is used to observe the structure and dynamics of Earth's plasmasphere from the Moon. By detecting the resonance line emission of helium i... The Extreme Ultraviolet Camera (EUVC) onboard the Chang'e-3 (CE-3) lander is used to observe the structure and dynamics of Earth's plasmasphere from the Moon. By detecting the resonance line emission of helium ions (He+) at 30.4 nm, the EUVC images the entire plasmasphere with a time resolution of 10 min and a spatial resolution of about 0.1 Earth radius (RE) in a single frame. We first present details about the data processing from EUVC and the data acquisition in the commissioning phase, and then report some initial results, which reflect the basic features of the plas- masphere well. The photon count and emission intensity of EUVC are consistent with previous observations and models, which indicate that the EUVC works normally and can provide high quality data for future studies. 展开更多
关键词 space vehicles: instruments: Extreme Ultraviolet Camera -- Earth: plas-masphere -- method: data processing
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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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Stochastic parallel gradient descent based adaptive optics used for a high contrast imaging coronagraph 被引量:2
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作者 Bing Dong De-Qing Ren Xi Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第8期997-1002,共6页
An adaptive optics (AO) system based on a stochastic parallel gradient descent (SPGD) algorithm is proposed to reduce the speckle noises in the optical system of a stellar coronagraph in order to further improve t... An adaptive optics (AO) system based on a stochastic parallel gradient descent (SPGD) algorithm is proposed to reduce the speckle noises in the optical system of a stellar coronagraph in order to further improve the contrast. The principle of the SPGD algorithm is described briefly and a metric suitable for point source imaging optimization is given. The feasibility and good performance of the SPGD algorithm is demonstrated by an experimental system featured with a 140-actuator deformable mirror and a Hartrnann-Shark wavefront sensor. Then the SPGD based AO is applied to a liquid crystal array (LCA) based coronagraph to improve the contrast. The LCA can modulate the incoming light to generate a pupil apodization mask of any pattern. A circular stepped pattern is used in our preliminary experiment and the image contrast shows improvement from 10^-3 to 10^-4.5 at an angular distance of 2A/D after being corrected by SPGD based AO. 展开更多
关键词 instrumentation: adaptive optics -- methods laboratory -- techniques: image processing CORONAGRAPH
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Characterizing motion types of G-band bright points in the quiet Sun 被引量:2
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作者 Yun-Fei Yang Hui-Xue Qu +4 位作者 Kai-Fan Ji Song Feng Hui Deng Jia-Ben Lin Feng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第4期569-582,共14页
We study the motion of G-band bright points (GBPs) in the quiet Sun to obtain the characteristics of different motion types. A high resolution image sequence taken with the Hinode/Solar Optical Telescope (SOT) is ... We study the motion of G-band bright points (GBPs) in the quiet Sun to obtain the characteristics of different motion types. A high resolution image sequence taken with the Hinode/Solar Optical Telescope (SOT) is used, and GBPs are automat- ically tracked by segmenting 3D evolutional structures in a space-time cube. After putting the GBPs that do not move during their lifetimes aside, the non-stationary GBPs are categorized into three types based on an index of their motion type. Most GBPs that move in straight or nearly straight lines are categorized as a straight mo- tion type, a few moving in rotary paths into rotary motion, and the others fall into a motion type we called erratic. The mean horizontal velocities are 2.18±0.08 km s-1, 1.63±0.09km s^-1 and 1.33±0.07 km s^-1 for straight, erratic and rotary motion types, respectively. We find that a GBP drifts at a higher and constant velocity during its whole life if it moves in a straight line. However, it has a lower and variational velocity if it moves on a rotary path. The diffusive process is ballistic-, super- and sub-diffusion for straight, erratic and rotary motion types, respectively. The corresponding diffusion index (γ) and coefficients (K) are 2.13±0.09 and 850±37km^2 s^-1, 1.82±0.07 and 331 ±24 km^2 s^-1, and 0.73±0.19 and 13±9 km^2 s^-1. In terms of direction of motion, it is homogeneous and isotropic, and usually persists between neighboring frames, no matter what motion type a GBP is classified as. 展开更多
关键词 techniques: image processing -- Sun: photosphere -- methods dataanalysis -- methods statistical
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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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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 《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 Study on the Multi-Objective Optimization Method of Brackets in Ship Structures
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作者 LIU Fan HU Yu-meng +2 位作者 FENG Guo-qing ZHAO Wei-dong ZHANG Ming 《China Ocean Engineering》 SCIE EI CSCD 2022年第2期208-222,共15页
The shape and size optimization of brackets in hull structures was conducted to achieve the simultaneous reduction of mass and high stress,where the parametric finite element model was built based on Patran Command La... The shape and size optimization of brackets in hull structures was conducted to achieve the simultaneous reduction of mass and high stress,where the parametric finite element model was built based on Patran Command Language codes.The optimization procedure was executed on Isight platform,on which the linear dimensionless method was introduced to establish the weighted multi-objective function.The extreme processing method was applied and proved effective to normalize the objectives.The bracket was optimized under the typical single loads and design waves,accompanied by the different proportions of weights in the objective function,in which the safety factor function was further established,including yielding,buckling,and fatigue strength,and the weight minimization and safety maximization of the bracket were obtained.The findings of this study illustrate that the dimensionless objectives share equal contributions to the multi-objective function,which enhances the role of weights in the optimization. 展开更多
关键词 BRACKETS parametric finite element model multi-objective optimization extreme processing method safety factor function weighted multi-objective function
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Reconstructing the landing trajectory of the CE-3 lunar probe by using images from the landing camera 被引量:2
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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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Evolution of isolated G-band bright points: size, intensity and velocity 被引量:1
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作者 Yun-Fei Yang Jia-Ben Lin +3 位作者 Song Feng Kai-Fan Ji Hui Deng Feng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第6期741-752,共12页
We study the evolution pattern of isolated G-band bright points (GBPs) in terms of their size, intensity and velocity. Using a high resolution image sequence taken with the Hinode/Solar Optical Telescope (SOT), we... We study the evolution pattern of isolated G-band bright points (GBPs) in terms of their size, intensity and velocity. Using a high resolution image sequence taken with the Hinode/Solar Optical Telescope (SOT), we detect GBPs in each image by the Laplacian and Morphological Dilation algorithm, and track their evolutions by a 26-adjacent method in a three-dimensional space-time cube. For quantifying the evolution, we propose a quantification method based on lifetime normalization which aligns the different lifetimes to common stages. The quantification results show that, on average, the diameter of isolated GBPs changes from 166 to 173 km, then down to 165 km; the maximum intensity contrast changes from 1.012 to 1.027, then down to 1.011; however, the velocity changes from 1.709 to 1.593 km s-1, then up to 1.703 km s-i. The results indicate that the evolution follows a pattern such that the GBP is small, faint and fast-moving at the birth stage, becomes big, bright and slow-moving at the middle stage, then gets small, faint and fast-moving at the decay stage until disappearance. Although the differences are very small, a two-sample t-test is used to demonstrate there are significant differences in means between the distri- butions of the different stages. Furthermore, we quantify the relationship between the lifetimes of GBPs and their properties. It is found that there are positive correlations between the lifetimes and their sizes and intensities with correlation coefficients of 0.83 and 0.65, respectively; however, there is a negative correlation between the life- times and velocities with a correlation coefficient of-0.49. In summary, the longer the GBP persists, the bigger, brighter and slower it will be. 展开更多
关键词 techniques: image processing -- Sun: photosphere -- methods dataanalysis -- methods statistical
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