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A WOMAN PACE-SETTER AMONG ASTRONOMERS——A SKETCHY PROFILE OF SENIOR ASTRONOMER YE SHUHUA
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作者 Huang Xin( Shanghai Branch of the CAS) 《Bulletin of the Chinese Academy of Sciences》 1996年第1期74-76,共3页
Ye Shuhua’s Astroid, the only celestial body named after a female Chinese scientist,roams the boundless universe. The starlet’s existence and radiance,just like Ye’s exploits in astronomic science,is indelible and ... Ye Shuhua’s Astroid, the only celestial body named after a female Chinese scientist,roams the boundless universe. The starlet’s existence and radiance,just like Ye’s exploits in astronomic science,is indelible and enduring whenever we stare out at the sun and the moon moving back and forth in the sky. 展开更多
关键词 A SKETCHY PROFILE OF SENIOR astronomer YE SHUHUA A WOMAN PACE-SETTER AMONG astronomerS PACE
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Chinese Astronomers Created an Empirical Stellar Spectra Library from LAMOST
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《Bulletin of the Chinese Academy of Sciences》 2018年第4期235-235,共1页
Astronomers from the National Astronomical Observatories of Chinese Academy of Sciences(NAOC) present an empirical stellar spectra library created with spectra from the LAMOST Data Release 5 (DR5). This library repres... Astronomers from the National Astronomical Observatories of Chinese Academy of Sciences(NAOC) present an empirical stellar spectra library created with spectra from the LAMOST Data Release 5 (DR5). This library represents a uniform data set and covers a wide span of parameter space. 展开更多
关键词 CHINESE astronomerS AN Empirical STELLAR Spectra LIBRARY LAMOST
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Chinese Astronomers Identify Nitrogen-Enhanced Field Stars in LAMOST DR3
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《Bulletin of the Chinese Academy of Sciences》 2018年第4期237-237,共1页
As a bar-spiral galaxy,our Milky Way(MW)is quite active chemically and dynamically.Among our MW stars,is it possible to know the evolution of each star,in order to accurately study the MW formation and evolution?Recen... As a bar-spiral galaxy,our Milky Way(MW)is quite active chemically and dynamically.Among our MW stars,is it possible to know the evolution of each star,in order to accurately study the MW formation and evolution?Recently,chemodynamics scholars try to understand the stellar and MW evolution history using both chemical and dynamic information. 展开更多
关键词 LAMOST CHINESE astronomerS Nitrogen-Enhanced Field Stars in LAMOST DR3 DR
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A Cross-matching Service for Data Center of Xinjiang Astronomical Observatory
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作者 Hai-Long Zhang Jie Wang +6 位作者 Xin-Chen Ye Wan-Qiong Wang Jia Li Ya-Zhou Zhang Xu Du Han Wu Ting Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期119-127,共9页
Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors, and proper motions of t... Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors, and proper motions of the celestial bodies, the same celestial object will have different positions in different catalogs, making it difficult to integrate multi-band or full-band astronomical data. In this study, we propose an online cross-matching method based on pseudo-spherical indexing techniques and develop a service combining with high performance computing system(Taurus) to improve cross-matching efficiency, which is designed for the Data Center of Xinjiang Astronomical Observatory. Specifically, we use Quad Tree Cube to divide the spherical blocks of the celestial object and map the 2D space composed of R.A. and decl. to 1D space and achieve correspondence between real celestial objects and spherical patches. Finally, we verify the performance of the service using Gaia 3 and PPMXL catalogs. Meanwhile, we send the matching results to VO tools-Topcat and Aladin respectively to get visual results. The experimental results show that the service effectively solves the speed bottleneck problem of crossmatching caused by frequent I/O, and significantly improves the retrieval and matching speed of massive astronomical data. 展开更多
关键词 virtual observatory tools astronomical databases:miscellaneous catalogs
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Astronomical influence of the development of Paleogene thin coal seam groups in offshore Lacustrine basins:A case study of the ZhuⅠDepression's Enping Formation located in the northern South China Sea
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作者 Yan Liu Shengbing Huang +4 位作者 Dongdong Wang Nan Li Yuting Yin Ying Chen Zengxue Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期136-150,共15页
The development of the Paleogene coal seams in China's offshore basin areas generally had the characteristics of coal measures with large thicknesses,large numbers of coal seams,thin single coal seams,poor stabili... The development of the Paleogene coal seams in China's offshore basin areas generally had the characteristics of coal measures with large thicknesses,large numbers of coal seams,thin single coal seams,poor stability,scattered vertical distribution,and a wide distribution range.This study selected the Enping Formation of the ZhuⅠDepression in the northern section of the South China Sea as an example to determine the macro-control factors of the development of the Paleogene coal seam groups.An analysis was carried out on the influencing effects and patterns of the astronomical cycles related to the development of the thin coal seam groups in the region.A floating astronomical time scale of the Enping Formation was established,and the sedimentary time limit of the Enping Formation was determined to be approximately 6.15 Ma±.In addition,the cyclostratigraphy analysis results of the natural gamma-ray data of Well XJ in the Enping Formation of the Xijiang Sag revealed that the development of the thin coal seams had probably been affected by short eccentricity and precession factors.The formation process of coal seams was determined to have been affected by high seasonal contrast,precipitation,and insolation.During the periods with high values of short eccentricity,the seasonal contrasts tended to be high.During those periods,fluctuations in the precession controls resulted in periodic volume changes in precipitation and insolation of the region,resulting in the development of thin coal seams.It was also found that the periods with low precession were the most conducive to coal seam development.On that basis,combined with such factors as sedimentary environmental conditions conducive to the development of thin coal seam groups,this study established a theoretical model of the comprehensive influences of short eccentricity and precession on the development and distribution of Paleogene thin coal seam groups in offshore lacustrine basins.The patterns of the Paleogene astronomical periods and paleoclimate evolution,along with the control factors which impacted the development of thin coal seam groups in offshore lacustrine basins,were revealed. 展开更多
关键词 PALEOGENE Pearl(Zhujiang)River Mouth Basin coal seam development astronomical cycles
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Cyclostratigraphy and paleoclimate analysis of the Lingshui Formation in Changchang Sag,Qiongdongnan Basin,China
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作者 Haizhang Yang Wu Tang +3 位作者 Enze Xu Shangfeng Zhang Yaning Wang Min Xu 《Energy Geoscience》 EI 2024年第1期108-120,共13页
The Qiongdongnan Basin,located in the sea between Hainan Island and the Xisha Islands,is a faulted Cenozoic basin on the northern continental margin of the South China Sea.The Changchang Sag,situated in the eastern pa... The Qiongdongnan Basin,located in the sea between Hainan Island and the Xisha Islands,is a faulted Cenozoic basin on the northern continental margin of the South China Sea.The Changchang Sag,situated in the eastern part of the central depressional zone in the deepwater area of the Qiongdongnan Basin,exhibits a near EW-striking morphology and represents an important potential target for oil/gas exploration.However,the age of the interface of the Lingshui Formation remains controversial,which hinders a comprehensive understanding of the tectonic evolution and hydrocarbon accumulation pattern in the Changchang Sag.This study focuses on well A,located in the depositional center of the Changchang Sag,and employs cyclostratigraphic analysis to identify cyclic signals of the Milankovitch cycles recorded in the sedimentary strata.Spectral analysis of natural gamma logging data from this well reveals the presence of 405 kyr long eccentricity cycles,100 kyr short eccentricity cycles,39.3 kyr obliquity cycles,and 20.58 kyr age precession cycles.By employing astronomical tuning,a“floating”astronomical time scale of the Lingshui Formation spanning 5.483 million years(Myr)is established.The top interface of the Oligocene in the International Geological Time Scale 2020(GTS2020),with a geological age of 23.03 Ma,is used as the time anchor to establish a high-precision absolute astronomical age framework for the Lingshui Formation.The results indicate that the bottom interface of the first member of the Lingshui Formation is dated at 23.79 Ma,the bottom interface of the second member is dated at 25.08 Ma,and the bottom interface of the third member is dated at 28.51 Ma.Additionally,the average sedimentation rate during this period is estimated to be 9.261 cm/kyr.Furthermore,paleoclimate and paleoenvironmental reconstructions were carried out through quantitative analysis of spore and pollen assemblages,as well as foraminifera within the Lingshui Formation.These analyses suggest that the deposition of the Lingshui Formation occurred under warm and humid temperate climatic conditions.The results of paleoclimate proxy analysis and comparative fitting analysis of the astronomical time scale confirm that the climate evolution during this period was influenced by astronomical orbital forces,such as eccentricity and precession. 展开更多
关键词 Milankovitch cycle PALEOCLIMATE Qiongdongnan Basin CYCLOSTRATIGRAPHY Astronomical time scale
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Astronomical Knowledge Entity Extraction in Astrophysics Journal Articles via Large Language Models
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作者 Wujun Shao Rui Zhang +7 位作者 Pengli Ji Dongwei Fan Yaohua Hu Xiaoran Yan Chenzhou Cui Yihan Tao Linying Mi Lang Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期140-155,共16页
Astronomical knowledge entities,such as celestial object identifiers,are crucial for literature retrieval and knowledge graph construction,and other research and applications in the field of astronomy.Traditional meth... Astronomical knowledge entities,such as celestial object identifiers,are crucial for literature retrieval and knowledge graph construction,and other research and applications in the field of astronomy.Traditional methods of extracting knowledge entities from texts face numerous challenging obstacles that are difficult to overcome.Consequently,there is a pressing need for improved methods to efficiently extract them.This study explores the potential of pre-trained Large Language Models(LLMs)to perform astronomical knowledge entity extraction(KEE)task from astrophysical journal articles using prompts.We propose a prompting strategy called PromptKEE,which includes five prompt elements,and design eight combination prompts based on them.We select four representative LLMs(Llama-2-70B,GPT-3.5,GPT-4,and Claude 2)and attempt to extract the most typical astronomical knowledge entities,celestial object identifiers and telescope names,from astronomical journal articles using these eight combination prompts.To accommodate their token limitations,we construct two data sets:the full texts and paragraph collections of 30 articles.Leveraging the eight prompts,we test on full texts with GPT-4and Claude 2,on paragraph collections with all LLMs.The experimental results demonstrate that pre-trained LLMs show significant potential in performing KEE tasks,but their performance varies on the two data sets.Furthermore,we analyze some important factors that influence the performance of LLMs in entity extraction and provide insights for future KEE tasks in astrophysical articles using LLMs.Finally,compared to other methods of KEE,LLMs exhibit strong competitiveness in multiple aspects. 展开更多
关键词 astronomical databases:miscellaneous virtual observatory tools methods:data analysis
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Review of artificial intelligence applications in astronomical data processing
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作者 Hailong Zhang Jie Wang +3 位作者 Yazhou Zhang Xu Du Han Wu Ting Zhang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期1-15,共15页
Artificial Intelligence(AI)is an interdisciplinary research field with widespread applications.It aims at developing theoretical,methodological,technological,and applied systems that simulate,enhance,and assist human ... Artificial Intelligence(AI)is an interdisciplinary research field with widespread applications.It aims at developing theoretical,methodological,technological,and applied systems that simulate,enhance,and assist human intelligence.Recently,notable accomplishments of artificial intelligence technology have been achieved in astronomical data processing,establishing this technology as central to numerous astronomical research areas such as radio astronomy,stellar and galactic(Milky Way)studies,exoplanets surveys,cosmology,and solar physics.This article systematically reviews representative applications of artificial intelligence technology to astronomical data processing,with comprehensive description of specific cases:pulsar candidate identification,fast radio burst detection,gravitational wave detection,spectral classification,and radio frequency interference mitigation.Furthermore,it discusses possible future applications to provide perspectives for astronomical research in the artificial intelligence era. 展开更多
关键词 Astronomical techniques Astronomical methods Astroinformatics
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Solar image reconstruction method under atmospheric turbulence at Fuxian Lake Solar Observatory
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作者 Sizhong Zou Zhenyu Jin +2 位作者 Kaifan Ji Jun Xu Lei Yang 《Astronomical Techniques and Instruments》 CSCD 2024年第2期128-139,共12页
Strong atmospheric turbulence reduces astronomical seeing,causing speckle images acquired by ground-based solar telescopes to become blurred and distorted.Severe distortion in speckle images impedes image phase deviat... Strong atmospheric turbulence reduces astronomical seeing,causing speckle images acquired by ground-based solar telescopes to become blurred and distorted.Severe distortion in speckle images impedes image phase deviation in the speckle masking reconstruction method,leading to the appearance of spurious imaging artifacts.Relying only on linear image degradation principles to reconstruct solar images is insufficient.To solve this problem,we propose the multiframe blind deconvolution combined with non-rigid alignment(MFBD-CNRA)method for solar image reconstruction.We consider image distortion caused by atmospheric turbulence and use non-rigid alignment to correct pixel-level distortion,thereby achieving nonlinear constraints to complement image intensity changes.After creating the corrected speckle image,we use the linear method to solve the wavefront phase,obtaining the target image.We verify the effectiveness of our method results,compared with others,using solar observation data from the 1 m new vacuum solar telescope(NVST).This new method successfully reconstructs high-resolution images of solar observations with a Fried parameter r0 of approximately 10 cm,and enhances images at high frequency.When r0 is approximately 5 cm,the new method is even more effective.It reconstructs the edges of solar graining and sunspots,and is greatly enhanced at mid and high frequency compared with other methods.Comparisons confirm the effectiveness of this method,with respect to both nonlinear and linear constraints in solar image reconstruction.This provides a suitable solution for image reconstruction in ground-based solar observations under strong atmospheric turbulence. 展开更多
关键词 Astronomical seeing Solar telescopes Solar observatories Astronomy image processing Phase error DECONVOLUTION
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Analysis of optical axis deviation caused by structural stiffness in equatorial telescopes
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作者 Haibo Li Runfu Peng +2 位作者 Chenggang Shu Yong Bi Shaoming Hu 《Astronomical Techniques and Instruments》 CSCD 2024年第4期203-210,共8页
The impact of structural stiffness on optical axis deviation poses a significant challenge in the design of equatorial telescope structures.A comprehensive analysis during the design process can reduce the reliance of... The impact of structural stiffness on optical axis deviation poses a significant challenge in the design of equatorial telescope structures.A comprehensive analysis during the design process can reduce the reliance of a telescope on advanced control technologies,thereby improving its economic feasibility.Although full-system finite element analyses are reliable,they are encumbered by significant time requirements and limitations in covering all possible telescope orientations.Therefore,we propose an efficient and comprehensive analytical method to evaluate the optical axis deviation of equatorial telescopes across a full range of angles.To address the challenge of ensuring that the analysis covers all possible positions of an equatorial telescope,based on a model from SiTian project,we analyze the optical axis deviations caused by the fork arm at 25 different angles and then use fitting methods to obtain results for all angles.Based on the analysis results of the optical axis deviation caused by the stiffness of the optical tube in the horizontal position,we derive the results for the tube at any position using geometric relationships.Finally,we calculate the coupling factors and combine these impacts.Furthermore,we identify six discrete feature points to reflect possible telescope orientations and conduct comprehensive finite element analyses.The results are in alignment with those acquired through a comprehensive computational approach. 展开更多
关键词 Astronomical instrumentation Telescopes Equatorial mounts Multivariate analysis
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Design and application of an autonomous Master Control System for a multi-layer magnetic and helioseismic telescope
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作者 Liyue Tong Yingzi Sun +8 位作者 Xiao Yang Jiaben Lin Yuanyong Deng Xianyong Bai Bingxiang Wang Xiaoming Zhu Yang Bai Yi Shang Hui Wang 《Astronomical Techniques and Instruments》 CSCD 2024年第3期187-196,共10页
With the growing significance of space weather forecasting,multi-layer magnetic and helioseismic telescopes are emerging as a key area of research.However,owing to the diverse operational processes and sophisticated h... With the growing significance of space weather forecasting,multi-layer magnetic and helioseismic telescopes are emerging as a key area of research.However,owing to the diverse operational processes and sophisticated hardware configurations of these devices,there is an urgent need for efficient autonomous observation capabilities.An autonomous Master Control System(MCS)can ensure efficient performance,data consistency,and stability,and the prototype presented here adopts a microservices architecture,breaking down the hardware into multiple subsystems and converting their functions into individual services.A central decision-making system leads the operations,supported by three auxiliary systems and three device control systems.Through inter-subsystem service calls,it achieves rapid imaging and spectroscopic monitoring.To verify system stability and observation efficiency,the system was tested on the Solar Full-disk Multi-layer Magnetograph.Experimental results verify this system can operate automatically for 4 consecutive months,acquire photospheric vector magnetic and Doppler velocity fields within a 15-minute interval,and measure chromospheric longitudinal magnetic and Doppler velocity fields in under 180 s.This ensures consistent and stable solar monitoring and serves as a practical methodological benchmark for the development of similar devices. 展开更多
关键词 Astronomical instrumentation Telescopes Solar optical telescopes Automated telescopes
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The Jiao Tong University Spectroscopic Telescope Project
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作者 JUST Team Chengze Liu +28 位作者 Ying Zu Fabo Feng Zhaoyu Li Yu Yu Hua Bai Xiangqun Cui Bozhong Gu Yizhou Gu Jiaxin Han Yonghui Hou Zhongwen Hu Hangxin Ji Yipeng Jing Wei Li Zhaoxiang Qi Xianyu Tan Cairang Tian Dehua Yang Xiangyan Yuan Chao Zhai Congcong Zhang Jun Zhang Haotong Zhang Pengjie Zhang Yong Zhang Yi Zhao Xianzhong Zheng Qingfeng Zhu Xiaohu Yang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期16-30,共15页
The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a di... The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a diameter of 1.1 m.JUST provides two Nasmyth platforms for placing science instruments.One Nasmyth focus fits a field of view of 10′and the other has an extended field of view of 1.2°with correction optics.A tertiary mirror is used to switch between the two Nasmyth foci.JUST will be installed at a site at Lenghu in Qinghai Province,China,and will conduct spectroscopic observations with three types of instruments to explore the dark universe,trace the dynamic universe,and search for exoplanets:(1)a multi-fiber(2000 fibers)medium-resolution spectrometer(R=4000-5000)to spectroscopically map galaxies and large-scale structure;(2)an integral field unit(IFU)array of 500 optical fibers and/or a long-slit spectrograph dedicated to fast follow-ups of transient sources for multi-messenger astronomy;(3)a high-resolution spectrometer(R~100000)designed to identify Jupiter analogs and Earth-like planets,with the capability to characterize the atmospheres of hot exoplanets. 展开更多
关键词 Astronomical instrumentation Optical telescopes Large-scale structure of the universe Redshift surveys Time domain astronomy Exoplanet astronomy
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Optical frequency comb technology: from ground to space
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作者 Xiaodong Shao Yu Yan +1 位作者 Hainian Han Zhiyi Wei 《Astronomical Techniques and Instruments》 CSCD 2024年第2期105-116,共12页
Optical frequency combs,as powerful tools for precision spectroscopy and research into optical frequency standards,have driven continuous progress and significant breakthroughs in applications such as time-frequency t... Optical frequency combs,as powerful tools for precision spectroscopy and research into optical frequency standards,have driven continuous progress and significant breakthroughs in applications such as time-frequency transfer,measurement of fundamental physical constants,and high-precision ranging,achieving a series of milestone results in ground-based environments.With the continuous maturation and evolution of femtosecond lasers and related technologies,optical frequency combs are moving from ground-based applications to astronomical and space-based applications,playing an increasingly important role in atomic clocks,exoplanet observations,gravitational wave measurements,and other areas.This paper,focusing on astronomical and space-based applications,reviews research progress on astronomical frequency combs,optical clock time-frequency networks,gravitational waves,dark matter measurement,dual-comb large-scale absolute ranging,and high-resolution atmospheric spectroscopy.With enhanced performance and their gradual application in the field of space-based research,optical frequency combs will undoubtedly provide more powerful support for astronomical science and cosmic exploration in the future. 展开更多
关键词 Optical frequency comb Astronomical comb Optical clock-based time and frequency network Gravitational waves and dark matter Dual-comb ranging
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USTC astronomers have measured the sizes of ~1000 quasar outflows
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《Science Foundation in China》 CAS 2019年第1期37-37,共1页
Under the support of the National Natural Science Foundation of China,the research team led by Prof.Wang TingGui(王挺贵)and Prof.Liu GuiLin(刘桂琳)at the CAS Key Laboratory for Research in Galaxies and Cosmology,Depar... Under the support of the National Natural Science Foundation of China,the research team led by Prof.Wang TingGui(王挺贵)and Prof.Liu GuiLin(刘桂琳)at the CAS Key Laboratory for Research in Galaxies and Cosmology,Department of Astronomy,University of Science and Technology of China(USTC),recently reported their novel method to measure the spatial scale of quasar outflows. 展开更多
关键词 USTC astronomerS MEASURED QUASAR OUTFLOWS
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Exploration of the relationship between the astronomical calendar and the origins of Qi,Yin and Yang,and the Five Elements
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作者 Qian-Wen He Ning Li 《History & Philosophy of Medicine》 2024年第3期16-22,共7页
Background:Traditional Chinese medicine(TCM)as a traditional Chinese medical practice,has gradually evolved into a coherent and systematic medical science based on natural principles and applied to human beings over t... Background:Traditional Chinese medicine(TCM)as a traditional Chinese medical practice,has gradually evolved into a coherent and systematic medical science based on natural principles and applied to human beings over time.The publication of the“Huangdi Neijing”(The Yellow Emperor’s Classic of Internal Medicine,Written between the Warring States period and the Qin and Han Dynasties,and finally compiled in the Western Han Dynasty,from 475 B.C.E.-8 C.E.)signified the establishment of a comprehensive theoretical framework for Chinese medicine.Due to the perspective of the‘correspondence between heaven and man’in TCM,the purpose of this paper is to explore the origin and development of the basic theories of TCM under the ancient astronomical view and the connection between the two.Methods:This paper emphases on the universe uninty with the humanities,philosophy,and medicine,starting with the forms of stargazing in ancient Chinese astronomy and the natural laws derived by the ancients from their observations of natural celestial phenomena.Results:Astronomy,arts and crafts,divination and medical correlations are based on the sequential changes of natural seasons.Conclusion:The operation of natural celestial phenomena and the characteristics of physical phenomena correspond to human physiology,and the development of the basic theories of Chinese medicine is inextricably linked to ancient astronomy,ancient philosophy,and ancient primeval science. 展开更多
关键词 basic theories of TCM ancient astronomical calendar Huangdi Neijing DIVINATION
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An Astronomer’s Tale
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作者 TANG YUANKAI 《Beijing Review》 2008年第15期25-25,共1页
Few visitors to Beijing would think the area around Beijing Railway Station a nice place to linger after seeing the station flooded with crowds of passengers.Yet a brick build- ing nearby,one of world’s oldest observ... Few visitors to Beijing would think the area around Beijing Railway Station a nice place to linger after seeing the station flooded with crowds of passengers.Yet a brick build- ing nearby,one of world’s oldest observatories,is well worth a tour. With its well-preserved architecture and equipment the Ancient Observatory is known internationally and has been visited by heads of state,government officials and renowned scientists and astronomers from around the world. 展开更多
关键词 An astronomer’s Tale
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International Team of Astronomers Finds New Planet
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作者 黄从晴 《当代外语研究》 2000年第9期1-2,共2页
提示:美国得克萨斯大学麦可唐纳天文台最近在太阳系附近发现一颗新的行星。这是天文学家在太阳系外至今发现的第41颗行星。这颗尚未被命名的新行星要比太阳系体积最大的木星还要大。它沿着离地球最近的一颗名为E-ERIDANI星座的行星轨道... 提示:美国得克萨斯大学麦可唐纳天文台最近在太阳系附近发现一颗新的行星。这是天文学家在太阳系外至今发现的第41颗行星。这颗尚未被命名的新行星要比太阳系体积最大的木星还要大。它沿着离地球最近的一颗名为E-ERIDANI星座的行星轨道运行。美国天文学家称,这犹如在我们人类的后花园找到了一颗新的行星。这颗被新发现的行星与E-ERIDANI星座相距4.78亿公里(约0.0000478光年),也就是说,在这颗新发现的行星上可能有生命的存在。另外,它的运行轨道像地球和其他附近行星的轨道一样,是稳定的,这是该行星有可能存在生命的一个重要因素。 展开更多
关键词 太阳系 天文学家 International Team of astronomers Finds New Planet
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Astronomers Eclipse Record for Most Distant Massive Object
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作者 Ann Arbor 邱立萍 《当代外语研究》 2005年第5期2-4,共3页
宇航员利用世界上最大的X射线和光学望远镜发现了一个离地球90亿光年远的星系群,这是迄今为止发现的离地球最远的大型天体。科学家为宇宙早期就存在这样一个庞大的星系群而感到非常惊讶,因为此前他们认为,这样复杂结构的星系群只有当宇... 宇航员利用世界上最大的X射线和光学望远镜发现了一个离地球90亿光年远的星系群,这是迄今为止发现的离地球最远的大型天体。科学家为宇宙早期就存在这样一个庞大的星系群而感到非常惊讶,因为此前他们认为,这样复杂结构的星系群只有当宇宙步入较晚的阶段才会产生。 展开更多
关键词 astronomers Eclipse Record for Most Distant Massive Object
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Narrowband EUV Sc/Si Multilayer for the Solar Upper Transition Region Imager at 46.5 nm 被引量:1
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作者 Runze Qi Jiali Wu +7 位作者 Jun Yu Chunling He Li Jiang Yue Yu Zhe Zhang Qiushi Huang Zhong Zhang Zhanshan Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第10期210-217,共8页
The transition region is the key region between the lower solar atmosphere and the corona, which has been limitedly understood by human beings. Therefore, the Solar Upper Transition Region Imager(SUTRI) was proposed b... The transition region is the key region between the lower solar atmosphere and the corona, which has been limitedly understood by human beings. Therefore, the Solar Upper Transition Region Imager(SUTRI) was proposed by Chinese scientists and launched in 2022 July. Right now, the first imaging observation of the upper transition region around 46.5 nm has been carried out by SUTRI. To ensure the spectral and temporal resolution of the SUTRI telescope, we have developed a narrowband Sc/Si multilayer. Based on the extreme ultraviolet(EUV)reflectivity measurements, the multilayer structure has been modified for ensuring the peak position of reflectivity was at 46.5 nm. Finally, the narrowband Sc/Si multilayer was successfully deposited on the hyperboloid primary mirror and secondary mirrors. The deviation of multilayer thickness uniformity was below than 1%, and the average EUV reflectivity at 46.1 nm was 27.8% with a near-normal incident angle of 5°. The calculated bandwidth of the reflectivity curve after primary and secondary mirrors was 2.82 nm, which could ensure the requirements of spectral resolution and reflectivity of SUTRI telescope to achieve its scientific goals. 展开更多
关键词 Astronomical Instrumentation Methods and Techniques instrumentation:high angular resolution Sun:UV radiation
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FAST Pulsar Database.I.Polarization Profiles of 682 Pulsars 被引量:1
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作者 P.F.Wang J.L.Han +6 位作者 J.Xu C.Wang Y.Yan W.C.Jing W.Q.Su D.J.Zhou T.Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第10期71-175,共105页
Pulsar polarization profiles form a very basic database for understanding the emission processes in a pulsar magnetosphere.After careful polarization calibration of the 19-beam L-band receiver and verification of beam... Pulsar polarization profiles form a very basic database for understanding the emission processes in a pulsar magnetosphere.After careful polarization calibration of the 19-beam L-band receiver and verification of beamoffset observation results,we obtain polarization profiles of 682 pulsars from observations by the Five-hundredmeter Aperture Spherical radio Telescope(FAST)duringthe Galactic Plane Pulsar Snapshot survey and other normal FAST projects.Among them,polarization profiles of about 460 pulsars are observed for the first time.The profiles exhibit diverse features.Some pulsars have a polarization position angle curve with a good S-shaped swing,some with orthogonal modes;some have components with highly linearly polarized components or strong circularly polarized components;some have a very wide profile,coming from an aligned rotator,and some have an interpulse from a perpendicular rotator;some wide profiles are caused by interstellar scattering.We derive geometric parameters for 190 pulsars from the S-shaped position angle curves or with orthogonal modes.We find that the linear and circular polarization or the widths of pulse profiles have various frequency dependencies.Pulsars with a large fraction of linear polarization are more likely to have a large Edot. 展开更多
关键词 POLARIZATION (stars:)pulsars:general astronomical databases:miscellaneous
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