检索结果-南通市图书馆

Probing the Galactic Halo with RR Lyrae Stars. VI. The Radial Velocity Curve Templates of RRc Stars

Research in Astronomy and Astrophysics 2024年第7期24卷 121-137页

作者： Yue Huang Min Fang Gaochao Liu Xianzhong Zheng Sarah Ann Bird Yang Huang Jianrong Shi Jiangtao Wang Huawei zhang Haijun Tian haotong zhang College of Science China Three Gorges University Center for Astronomy and Space Sciences China Three Gorges University Purple Mountain Observatory Chinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China School of Astronomy and Space Science University of Chinese Academy of Sciences CAS Key Laboratory of Optical Astronomy National Astronomical Observatories Department of Astronomy School of PhysicsPeking University Kavli Institute for Astronomy and Astrophysics Peking University School of Sciences Hangzhou Dianzi University

We present radial velocity（RV） curve templates of RR Lyrae first-overtone（RRc） stars constructed with the Mg I b triplet and Hα lines using time-domain Medium-Resolution Survey spectra of seven RRc stars from Large Sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST） Data Release 9. Additionally, we derive the relation between the stellar RV curve amplitudes and g-band light curve amplitudes from Zwicky Transient Facility（ZTF）public survey. For those RRc stars without ZTF g-band light curves, we provide the conversions from the light curve amplitudes in ZTF r-and i-bands, Gaia G-band, and V-band from the All-Sky Automated Survey for Supernovae to those in ZTF g-band. We validate our RV curve templates using the RRc star SV Scl and find the uncertainties of systemic RV are less than 2.11 km s-1and 6.08 km s-1based on the Mg I b triplet and Hα lines,respectively. We calculate the systemic RVs of 30 RRc stars using the RV curve templates constructed with the Mg I b triplet and Hα lines and find the systemic RVs are comparable with each other. This RV curve template will be particularly useful for obtaining the systemic RV of RRc using the LAMOST spectroscopy.

关键词： Stars stars: variables: RR Lyrae techniques: radial velocities

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The Jiao Tong University Spectroscopic Telescope Project

引用

Astronomical Techniques and Instruments 2024年第1期1卷 16-30页

作者： JUST Team Chengze Liu 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 Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Department of Astronomy School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China University of Chinese Academy of Sciences NanjingNanjing 211135China University of Chinese Academy of Sciences Beijing 101408China Lenghu Technology Innovation Industrial Park Management Committee Lenghu 817400China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic *** JUST primary mirror is composed of 18 hexagonal segments,each with a diameter of 1.1 *** provides two Nasmyth platforms for placing science *** 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 *** 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.

关键词： Astronomical instrumentation Optical telescopes Large-scale structure of the universe Redshift surveys Time domain astronomy Exoplanet astronomy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

“实验设计与统计分析”在食品科学与工程专业中的教学改革探索

引用

农产品加工 2024年第6期 122-124,130页

作者：杨瑞刘畅张昊彤李文钊天津科技大学食品科学与工程学院天津300457

“实验设计与统计分析”是关于数理统计原理和方法的应用课程,是食品科学与工程专业及其相近专业课程的重要基础课程。该课程对于培养食品科学与工程专业学生的数据分析与实验设计的能力有着尤为重要的意义。以“实验设计与统计分析”... 详细信息

“实验设计与统计分析”是关于数理统计原理和方法的应用课程,是食品科学与工程专业及其相近专业课程的重要基础课程。该课程对于培养食品科学与工程专业学生的数据分析与实验设计的能力有着尤为重要的意义。以“实验设计与统计分析”课程教学过程中存在的教学模式单一、内容抽象难懂、软件普及不足等问题为切入点,提出了强化上机实践、丰富统计软件等改革策略和措施,旨在培养具有大数据分析能力的应用型食品专业人才。

关键词：实验设计与统计分析食品专业实践教学改革

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

引用

Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai Huan Li Xiao Tang Ruonan zhang haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum *** tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded *** fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent *** tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV ***,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation *** further propose an iterative power allocation algorithm based on the sequential convex approximation *** simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The nearest neutron star candidate in a binary revealed by optical time-domain surveys

引用

Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 184-202页

作者： Ling-Lin Zheng Mouyuan Sun Wei-Min Gu Tuan Yi Zhi-Xiang zhang Pei Wang Junfeng Wang Jianfeng Wu Shan-Shan Weng Song Wang Sen-Yu Qi Jia zhang Chun-Qian Li Jian-Rong Shi Yong Shao Xiang-Dong Li Jin-Bo Fu Fan Yang Zhongrui Bai Yu Bai haotong zhang Jifeng Liu Department of Astronomy Xiamen UniversityXiamen 361005China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Physics Institute of Theoretical PhysicsNanjing Normal UniversityNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216China College of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 210023China

The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on *** remnants of such supernovae are too old to be easily *** is therefore of great interest to search for million-year-old near-Earth neutron stars or black holes,the products of ***,neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray *** we report the discovery of one of the nearest(127.7±0.3 pc)neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9(hereafter J2354).Utilizing the time-resolved ground-based spectroscopy and space photometry,we find that J2354 hosts an unseen compact object with M_(inv)being 1.4-1.6 M_(⊙).The follow-up Swift ultraviolet(UV)and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact ***,J2354 probably harbours a neutron star rather than a hot ultramassive white ***-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σflux upper limit of 12.5μ***,the neutron star candidate in J2354 can only be revealed via our time-resolved ***,the distance between J2354 and our Earth can be as close as~50 pc around 2.5 million years(Myrs)ago,as revealed by the Gaia *** discovery demonstrates a promising way to unveil the hidden near-Earth neutron stars in binaries by exploring the optical time domain,thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood.

关键词： neutron stars binary stars stellar evolution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The effects of spectrograph slit modes on the accuracy of stellar radial velocity measurement and atmospheric parameter estimation

引用

Science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1833-1839页

作者： WANG FengFei zhang haotong LUO ALi BAI ZhongRui DU Bing ZHAO YongHeng National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

Spectrograph slit is conventionally used to enhance the spectral resolution and manage how much light can be allowed to enter *** narrow slit provides a higher resolution but sacrifices efficiency of spectrograph and results in a low signal to noise ratio(S/N) spectra *** take GuoShouJing telescope as an example and carry out a series of experiments to study how its 2/3 slit mode affects the precision of stellar radial velocity measurement and atmosphere parameters *** transforming the resolution and adding a Gaussian White Noise to the extremely high quality spectra from the Sloan Digital Sky Survey,we generate synthetic stellar spectra of various brightness with different S/*** the measurements on these noise added spectra with the original high quality ones,we summarize the influences of the 2/3 slit mode on the measurement accuracy of stellar radial velocity and atmospheric parameters.

关键词：径向速度测量大气参数参数估计狭缝恒星摄谱仪光谱分辨率信号噪声比

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A quasar possibly ejected from NGC4579

引用

Chinese Science Bulletin 2000年第10期45卷 886-888页

作者： ZHU Xingfen CHU Yaoquan WEI Jianyan zhang haotong HU Jingyao Center for Astrophysics University of Science and Technology of ChinaHefei 230026China Beijing Astronomical Observatory Chinese Academy of SciencesBeijing 100012China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

With the 2.16 m telescope at Beijing Astronomical Observatory, it is identified that a compact X-ray source detected by ROSAT located in the vicinity of 5’ .9 from the LINER galaxy NGC4579 is a quasar with a redshift... 详细信息

关键词： quasar-galaxy-redshift.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Fault Diagnosis of the LAMOST Fiber Positioner Based on a Long Short-term Memory(LSTM)Deep Neural Network

引用

Research in Astronomy and Astrophysics 2023年第12期23卷 81-95页

作者： Yihu Tang Yingfu Wang Shipeng Duan Jiadong Liang Zeyu Cai Zhigang Liu Hongzhuan Hu Jianping Wang Jiaru Chu Xiangqun Cui Yong zhang haotong zhang Zengxiang Zhou Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)has been in normal operation for more than 10 yr,and routine maintenance is performed on the fiber positioner every *** positioning accuracy of the fiber positioner directly affects the observation performance of LAMOST,and incorrect fiber positioner positioning accuracy will not only increase the interference probability of adjacent fiber positioners but also reduces the observation efficiency of *** present,during the manual maintenance process of the positioner,the fault cause of the positioner is determined and analyzed when the positioning accuracy does not meet the preset *** causes maintenance to take a long time,and the efficiency is *** quickly locate the fault cause of the positioner,the repeated positioning accuracy and open-loop calibration curve data of each positioner are obtained in this paper through the photographic measurement *** on a systematic analysis of the operational characteristics of the faulty positioner,the fault causes are *** training a deep learning model based on long short-term memory,the positioner fault causes can be quickly located to effectively improve the efficiency of positioner fault cause *** relevant data can also provide valuable information for annual routine maintenance methods and positioner designs in the *** method of using a deep learning model to analyze positioner operation failures introduced in this paper is also of general significance for the maintenance and design optimization of fiber positioners using a similar double-turn gear transmission system.

关键词： telescopes-techniques image processing-methods analytical-techniques spectroscopic

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

PBX/Knotted 1 homeobox-2(PKNOX2)is a novel regulator of myocardial fibrosis

引用

Signal Transduction and Targeted Therapy 2024年第5期9卷 2231-2249页

作者： Liang Chen haotong Li Xiaorui Liu Ningning zhang Kui Wang Anteng Shi Hang Gao Deniz Akdis Ardan MSaguner Xinjie Xu Elena Osto Willem Van de Veen Guangyu Li Antoni Bayés-Genís Firat Duru Jiangping Song Xiangjie Li Shengshou Hu State Key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingP.R.China School of Statistics and Data Science Nankai UniversityTianjinChina Department of Cardiology University Heart CenterUniversity Hospital Zurich and University of ZurichZurichSwitzerland Institute for Clinical Chemistry University Hospital Zurich and University of ZürichZurichSwitzerland Swiss Institute of Allergy and Asthma Research(SIAF) University of ZurichDavosSwitzerland Heart Institute Hospital Universitari Germans Trias i PujolBadalonaCIBERCVSpain

Much effort has been made to uncover the cellular heterogeneities of human hearts by single-nucleus RNA ***,the cardiac transcriptional regulation networks have not been systematically described because of the limitations in detecting transcription *** this study,we optimized a pipeline for isolating nuclei and conducting single-nucleus RNA sequencing targeted to detect a higher number of cell signal genes and an optimal number of transcription *** this unbiased protocol,we characterized the cellular composition of healthy human hearts and investigated the transcriptional regulation networks involved in determining the cellular identities and functions of the main cardiac cell *** in fibroblasts,a novel regulator,PKNOX2,was identified as being associated with physiological fibroblast activation in healthy *** validate the roles of these transcription factors in maintaining homeostasis,we used single-nucleus RNA-sequencing analysis of transplanted failing hearts focusing on fibroblast *** trajectory analysis suggested that PKNOX2 was abnormally decreased from fibroblast activation to pathological myofibroblast *** gain-and loss-of-function in vitro experiments demonstrated the inhibitory role of PKNOX2 in pathological fibrosis ***,fibroblast-specific overexpression and knockout of PKNOX2 in a heart failure mouse model induced by transverse aortic constriction surgery significantly improved and aggravated myocardial fibrosis,*** summary,this study established a high-quality pipeline for single-nucleus RNA-sequencing analysis of heart *** this optimized protocol,we described the transcriptional regulation networks of the main cardiac cell subtypes and identified PKNOX2 as a novel regulator in suppressing fibrosis and a potential therapeutic target for future translational studies.

关键词： NOX2 homeostasis fibrosis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Overview of the LAMOST survey in the first decade

引用

The Innovation 2022年第2期3卷 49-64页

作者： Hongliang Yan Haining Li Song Wang Weikai Zong Haibo Yuan Maosheng Xiang Yang Huang Jiwei Xie Subo Dong Hailong Yuan Shaolan Bi Yaoquan Chu Xiangqun Cui Licai Deng Jianning Fu Zhanwen Han Jinliang Hou Guoping Li Chao Liu Jifeng Liu Xiaowei Liu Ali Luo Jianrong Shi Xuebing Wu haotong zhang Gang Zhao Yongheng Zhao CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Max-Planck Institute for Astronomy Königstuhl69117HeidelbergGermany South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing 210093China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China University of Science and Technology of China Hefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesCASBeijing 100101China WHU-NAOC Joint Center for Astronomy Wuhan UniversityWuhan 430072China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),also known as the Guoshoujing Telescope,is a major national scientific facility for astronomical research located in Xinglong,*** with a pilot survey in 2011,LAMOST has been surveying the night sky for more than 10 *** LAMOST survey covers various objects in the Universe,from normal stars to peculiar ones.

关键词： China survey surveying

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：