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Primary scientific results of Chang'E-1 lunar mission

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Science china Earth sciences 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2, LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5, WANG HuanYu6, ZHANG XiaoHui7, WANG shiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, XU Chun1, shi ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china 2 Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3 Xi’an Institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119, china 4 Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 200083, china 5 purple mountain observatory, chinese academy of sciences, nanjing 2.0008, china 6 Institute of High Energy Physics, chinese academy of sciences, Beijing 100049, china 7 Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190, china National Astronomical Observatories Chinese Academy of Sciences Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai China purple mountain observatory Chinese Academy of Sciences Nanjing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results

A Preliminary Study on Traditional Level-trench Method to Prevent Rill Initiation in the Three Gorges Region,china

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Journal of mountain Science 2011年第6期8卷 876-881页

作者： YAN Dongchun WEN Anbang HE Xiubin shi Zhonglin XIONG Donghong LONG Yi Key Laboratory of mountain Environment Evolution and Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan 610041 China Graduate University of chinese academy of sciences Beijing 100049 China

The level-trench method is a traditional tillage operation to develop a drainage system on slope land in the Three Gorges region. Before crops are planted, farmers prepare the land with level trenches spaced 3-1o m apart, depending on the slope gradient： steeper slopes require shorter distances. Little scientific analysis has been done on the use of traditional level trenches for soil conservation. We conducted a field investigation and simulation experiments, and present a comparison between the spacing of level trenches and the slope length required for rill initiation. The results indicate that the spacing of level trenches in farmland is close to the slope length required for rill initiation in the experimental plots, and regression models of trench spacing with the gradient and the slope length required for rill initiation with the gradient have similar formats; the coefficients of determination （R2） for the two equations are 0.99 and 0.88, respectively. There were some differences between the field survey and experiments, but we conclude that the traditional level-trench method has an important role in preventing rill initiation.

关键词： Level trench Rill Initiation purple Soil Three Gorges Region

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中国古历定朔推步综述

天文学进展 1996年第1期14卷 66-76页

作者：李勇张培瑜南京大学天文系南京210008 中国科学院紫金山天文台南京210008

“朔”简言之表日月黄经相等，先民对其认识经历了一个从平朔到定朔的过程。通过研读古历，文中分析并归纳了不同时期中国古历日制度的基本元素之一──朔的两种推步方法：“积年法”和“《授时历》法”，其中包括平朔、日躔、月离、及... 详细信息

“朔”简言之表日月黄经相等，先民对其认识经历了一个从平朔到定朔的过程。通过研读古历，文中分析并归纳了不同时期中国古历日制度的基本元素之一──朔的两种推步方法：“积年法”和“《授时历》法”，其中包括平朔、日躔、月离、及定朔的推步方法等；得出了由各历的基本历数直接推出的中国古历定朔计算的一般公式；同时亦给出了《授时历》的推朔法和部分算例。

关键词：天文学史古历定朔推步法

The effects of parametrization of the dark energy equation of state

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Research in Astronomy and Astrophysics 2011年第12期11卷 1403-1412页

作者： Ke shi Yong-Feng Huang1,2 Tan Lu Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Nanjing 210093 China purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing University - Purple Mountain Observatory Nanjing 210093 China

We investigate in detail the influence of parametrizations of the dark energy equation of state on reconstructing dark energy geometrical parameters, such as the deceleration parameter q（z） and Om diagnostic. We use a type Ia supernova sample, baryon acoustic oscillation data, cosmic microwave background information along with twelve observational Hubble data points to constrain cosmological parameters. With the joint analysis of these current datasets, we find that the parametrizations of w（z） have little influence on the reconstruction result of q（z） and Ore. The same is true for the transition （cosmic deceleration to acceleration） redshift zt, for which we find that for different parametrizations of w（z）, the best fitted values of zt are very close to each other （about 0.65）. All of our results are in good agreement with the ACDM model. Furthermore, using the combination of datasets, we do not find any signal of decreasing cosmic acceleration as suggested in some recent papers. The results suggest that the influence of the prior w（z） is not as severe as one may anticipate, and thus we can, to some extent, safely use a reasonable parametrization of w（z） to reconstruct some other dark energy parameters （e.g. q（z）, Ore） with a combination of datasets.

关键词： cosmology: observations -- cosmology: cosmological parameters

基于TCP/IP的CASCAM网络控制系统

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天文学报 2004年第2期45卷 229-236页

作者：任诗波姚永强姚大志中国科学院紫金山天文台南京210008

介绍了基于TCP/IP协议的CASCAM网络控制系统。为了有效地实现Client/Server模式的网络通信,我们开发了两个类——client、server,实现了工作站和微机之间的网络连接,并在客户端使用Tcl/Tk脚本语言编写控制界面,通过加载client类的动态... 详细信息

介绍了基于TCP/IP协议的CASCAM网络控制系统。为了有效地实现Client/Server模式的网络通信,我们开发了两个类——client、server,实现了工作站和微机之间的网络连接,并在客户端使用Tcl/Tk脚本语言编写控制界面,通过加载client类的动态库向服务器发送请求,服务器端接收请求并解析请求,从而控制相机系统。

关键词：仪器红外相机网络控制 TCP/IP协议网络连接红外天文观测

Upgrade Procedure for the Delingha 13.7-m Telescope

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chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 390-396页

作者： Ying-XiZuo JiYang Sheng-Caishi Shan-HuaiChen Li-BenPei Qi-JunYao Jin-JiangSun Zhen-HuiLin purplemountainobservatory ChineseAcademyofSciencesNanjing210008

The 13.7-m millimeter-wave radio telescope of purple mountain observatory operates at 3200-m above the sea level near Delingha, Qinghai Province, china. Equipped with a superconducting SIS receiver, the telescope is used in the millimeter-wave band ranging from 85 to 115 GHz. An upgrade procedure is reported here which includes a superconducting SIS receiver, a new phase-locked local oscillator, a dedicated multi-line backend system, and a new control system based on industrial computer with PCI bus. With the dedicated multi-line backend system, the CO and isotopic lines around 110 GHz are obtained simultaneously. In recent years, scientific activities with this telescope have been focused on studies of Galactic molecular clouds and star formation regions, including surveys of molecular lines from IRAS sources and large-scale map of molecular clouds. Other programs include studies of the circumstellar envelope of late-type stars and interaction of Galactic supernova remnants with dense molecular gas.

关键词： telescopes: radio telescope millimeter wavelength astronomy instrument

Achieving full mutualism with massive passive devices for multiuser MIMO symbiotic radio

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Science china(Information sciences) 2024年第9期67卷 196-212页

作者： Jingran XU Zhuoyin DAI Yong ZENG shi JIN Tao JIANG National Mobile Communications Research Laboratory Southeast University purple mountain Laboratories Research Center of 6G Mobile Communications School of Cyber Science and Engineering and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

Symbiotic radio(SR) is one of the attractive communication technologies to facilitate largescale Internet of Things(IoT) connections with enhanced energy and spectrum efficiency, where passive backscatter devices(BDs) modulate their information over the radio frequency(RF) signals emitted by the active primary transmitters(PTs). Meanwhile, the primary transmission can be strengthened with the additional multipaths created by BDs. To capitalize to a greater extent on the mutualism relationship between the two types of communication, this paper studies multiple-input multiple-output(MIMO) SR communication systems including multiple PTs and massive BDs. We derive the achievable rate expressions of each PT and BD, as well as the sum rate expressions of primary and secondary communication, *** asymptotic analysis is given to derive the active and passive communication rates with a large number of BDs. Furthermore, for the general case with a finite number of BDs, we study the precoding optimization problem to maximize the sum rate of primary communication, while ensuring that the sum rate of secondary communication and the individual rate for each PT and BD in the prescribed active and passive user sets satisfy the specified thresholds. Simulation results are presented to verify the analytical studies.

关键词： multiuser MIMO SR backscattering massive backscatter devices asymptotic analysis active and passive communication

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan Wei Jiang Chuan Yue shi-Jun Lei Yu-Xin Cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

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光学-近红外相机CASCAM的机械设计

天文学进展 2004年第4期22卷 334-343页

作者：吴建文任诗波季春宏姚永强姚大志中国科学院紫金山天文台南京210008

光学-近红外相机CASCAM(chinese academy of sciences,Camera)采用光学CCD和近红外阵列HAWAII-1(*** Wide Area Infrared Imaging)探测器,配备兴隆2.16 m望远镜可同时进行光学、近红外成像和偏振观测。CASCAM的机械系统主要包括光学箱... 详细信息

光学-近红外相机CASCAM(chinese academy of sciences,Camera)采用光学CCD和近红外阵列HAWAII-1(*** Wide Area Infrared Imaging)探测器,配备兴隆2.16 m望远镜可同时进行光学、近红外成像和偏振观测。CASCAM的机械系统主要包括光学箱、真空箱以及致冷设计。其中光学箱是相机光学系统和探测器的载体,同时防止来自光学箱外部的红外热辐射;真空箱位于光学箱外部,它是整个系统的机械支撑,保证相机有良好的真空密封性能,并和真空泵、冷冻机一起构成了相机的致冷系统。

关键词：天文观测设备与技术 CASCAM 机械设计致冷系统