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Restoration of desertified grassland and challenges in northern China——for the possibility of sustained desertification reversion

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Restoration of desertified grassland and challenges in north...

Querying Large Physics Data Sets Over an Information Grid

ⅩⅪ International Grassland Congress and the Ⅷ International Rangeland Congress

作者： Xue-yong Zhao Ha-lin Zhao Xiao-an Zuo Ya-yong Luo Shao-kun Wang ~* Zhi-qiang Kou Hao Qu Naiman Desertification Research Station cern Lanzhou 730000 * Inner Mongolia Hydrological Research Institute Hohhot 010000

＜正＞Key points:There is about 0.39 billion ha of grassland in China,covering about 40%of the country’ s land,of which 52%is in the western five provinces.However,about 70%of the grassland is desertified due to climate and land use changes.Through more than 50 years of efforts in combating desertification,grassland desertification was reversed in northern China,particularly in Horqin Sand Land of Inner Mongolia.

关键词： grassland desertification climate change land use change reversion

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Querying Large Physics Data Sets Over an Information Grid

高能氧核诱发作用中粒子关联和涨落的极限碎裂行为

International Conference on Computing in High Energy and Nuclear Physics

作者： NigelBaker PeterBrooks ZsoltKovacs cern.ch Jean-MarieLeGoff cern.ch RichardMcClatchey Centre for Complex Cooperative Systems UWE Frenchay Bristol BS16 1QY UK Richard. Centre for Complex Cooperative Systems UWE Frenchay Bristol BS16 1QY UK Richard. EP Division CERN Geneva Switzerland Jean-Marie. Le. Goff EP Division CERN Geneva Switzerland Jean-Marie. Le. Goff Centre for Complex Cooperative Systems UWE Frenchay Bristol BS16 1QY UK Richard.

ISBN: (纸本)188013277X

＜正＞Optimising use of the Web （WWW） for LHC data analysis is a complex problem and illustrates the challenges arising from the integration of and computation across massive amounts of information distributed worldwide. Finding the right piece of information can, at times, be extremely time-consuming, if not impossible. So-called Grids have been proposed to facilitate LHC computing and many groups have embarked on studies of data replication, data migration and networking philosophies. Other aspects such as the role of ’middleware’ for Grids are emerging as requiring research. This paper positions the need for appropriate middleware that enables users to resolve physics queries across massive data sets. It identifies the role of meta-data for query resolution and the importance of Information Grids for high-energy physics analysis rather than just Computational or Data Grids. This paper identifies software that is being implemented at cern to enable the querying of very large collaborating HEP data-sets, initially being employed for the construction of CMS detectors.

关键词： Representation of data information cern Metadata Large Hadron Collider Dataset Middleware Grid computing Physics Data analysis

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高能物理与核物理 1992年第11期16卷 991-999页

作者： cern/EMU01国际合作组

本文系统地研究了每核子从3.7到200GcV的束流能区氧核诱发作用中的单粒子赝快度分布和二粒子关联极限碎裂行为。利用阶乘矩与多粒子的赝快度分布的关系、考察了多粒子分布动力学涨落的极限碎裂行为。

关键词：粒子相关涨落极限碎裂快度

Dense matter with eXTP

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Science China(Physics,Mechanics & Astronomy) 2019年第2期62卷 28-44页

作者： Anna L.Watts WenFei Yu Juri Poutanen Shu Zhang Sudip Bhattacharyya Slavko Bogdanov Long Ji Alessandro Patruno Thomas E.Riley Pavel Bakala Altan Baykal Federico Bernardini Ignazio Bombaci Edward Brown Yuri Cavecchi Deepto Chakrabarty Jér?me Chenevez Nathalie Degenaar Melania Del Santo Tiziana Di Salvo Victor Doroshenko Maurizio Falanga Robert D.Ferdman Marco Feroci Angelo F.Gambino MingYu Ge Svenja K.Greif Sebastien Guillot Can Gungor Dieter H.Hartmann Kai Hebeler Alexander Heger Jeroen Homan Rosario Iaria Jean in 't Zand Oleg Kargaltsev Aleksi KurkelaTheoretical Physics Department cern XiaoYu Lai Ang Li XiangDong Li ZhaoSheng Li Manuel Linares FangJun Lu Simin Mahmoodifar Mariano Méndez M.Coleman Miller Sharon Morsink Joonas N?ttil? Andrea Possenti Chanda Prescod-Weinstein JinLu Qu Alessandro Riggio Tuomo Salmi Andrea Sanna Andrea Santangelo Hendrik Schatz Achim Schwenk LiMing Song Eva?rámková Benjamin Stappers Holger Stiele Tod Strohmayer Ingo Tews Laura Tolos Gabriel T?r?k David Tsang Martin Urbanec Andrea Vacchi RenXin Xu YuPeng Xu Silvia Zane GuoBao Zhang ShuangNan Zhang WenDa Zhang ShiJie Zheng Xia Zhou Anton Pannekoek Institute for Astronomy University of Amsterdam Shanghai Astronomical Observatory Tuorla Observatory Department of Physics and Astronomy University of Turku Nordita KTH Royal Institute of Technology and Stockholm University Institute of High Energy Physics Chinese Academy Sciences Tata Institute of Fundamental Research Columbia Astrophysics Laboratory Columbia University Institut für Astronomie und Astrophysik Tübingen Universit?t Tübingen Leiden Observatory Leiden University Research Center for Computational Physics and Data Processing Silesian University in Opava Physics Department Middle East Technical University INAF Osservatorio Astronomico di Roma New York University Abu Dhabi Dipartimento di Fisica Enrico Fermi University of Pisa INFN Italian National Institute for Nuclear Physics Department of Physics and Astronomy Michigan State University Department of Astrophysical Sciences Princeton University Mathematical Sciences and STAG Research Centre University of Southampton MIT Kavli Institute for Astrophysics and Space Research DTU Space Technical University of Denmark INAF/IASF Palermo via Ugo La Malfa 153 Universita degli Studi di Palermo Dipartimento di Fisica e Chimica International Space Science Institute (ISSI) Faculty of Science University of East Anglia INAF Istituto di Astrofisica e Planetologie Spaziali Institut für Kernphysik Technische Universit?t Darmstadt ExtreMe Matter Institute EMMI GSI Helmholtzzentrum für Schwerionenforschung GmbH Instituto de Astrof'?sica Pontificia Universidad Católica de Chile Department of Physics & Astronomy Kinard Lab of Physics Clemson University School of Physics and Astronomy Monash University SRON Netherlands Institute for Space Research Department of Physics The George Washington University Faculty of Science and Technology University of Stavanger School of Physics and Mechanical & Electrical Engineering Hubei University of Education Department of Astronomy Xiamen University (Haiyun Campus) School of Astronomy and Space

In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry(eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Sciences, the eXTP mission is expected to be launched in the mid 2020 s.

关键词： neutron X-rays dense matter equation of state

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愤怒的飞行员:大卫·切尔尼

青年视觉 2018年第2期 250-263页

作者：朱越 David cerný(photo) 不详

破坏分子,挑者,布拉格叛逆艺术家,安东尼·葛姆雷(Antony Gormley)与达明安赫斯特(Damien Hirst)结合体,一个不合时宜的人·雕塑家大卫·切尔尼(David cerný)或许是捷克当代最具国际影响力的一位艺术家,却也是最声名狼籍的一个。切尔尼1... 详细信息

破坏分子,挑者,布拉格叛逆艺术家,安东尼·葛姆雷(Antony Gormley)与达明安赫斯特(Damien Hirst)结合体,一个不合时宜的人·雕塑家大卫·切尔尼(David cerný)或许是捷克当代最具国际影响力的一位艺术家,却也是最声名狼籍的一个。切尔尼1967年生于布拉格,1988年至1996年在布拉格艺术与建筑设计学院学习,期间曾在瑞士与美国为艺术项目停留过几年时间,除此之外,捷克始终是他创作和思考的背景与主题。同切尔尼在布拉格无处不在的雕塑作品一样闻名的,就是他针对政治精英与民族文化发表的讽刺性言论。他的名字如同一把尖锥,时刻搅动着捷克社会政治的水域,以阻止人们在安稳中溺水身亡。

关键词：讽刺性大卫雕塑作品政治精英赫斯特建筑设计布拉格不合时宜

富营养水体中肥沃底质对沉水植物生长的胁迫(英文)

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水生生物学报 2001年第4期25卷 399-405页

作者：倪乐意中国科学院水生生物研究所东湖生态站淡水生态学和生物技术国家重点实验室武汉430072

Submersed macrophytes are real water plants because they are rooted in sediment and can complete their growth and reproduction inside the overlying water. Providing a linkage between water and sediment, they have the closest interaction with water environment. This interaction is very complicate partly because sediment are not only served as a base of physical attachment. Recent attention has focused on the effects of submersed macrophytes on sediment redox, nutrient statues and the effects of sediment organic composition on macrophyte growth. This line of investigation has been thoroughly reviewed by Barko et al.(1991). Long-term ecological records of the decline of submersed macrophytes in the progress of eutrophication have suggested that sediment may play an important role for the decline due to its close relations to macrophyte growth and distribution. Therefore, more concerns should be given to the inhibitory effects of fertile sediment on submersed macrophytes when nutrients are excessive for their growth. However, this line of investigation and experiments are relatively weak up-to-date.

关键词：肥沃底质生长胁迫耐受沉水植物生长富营养水体

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粒子物理的前景

科学 1987年第4期 269-273页

作者：范霍夫朱伟欧洲核子研究中心

粒子物理研究目前似乎处于一种左右为难的境地。要作出抉择,就要对其前景作一番讨论。这里发表范霍夫教授的意见。

关键词：夸克标准模型层子假设粒子试验模型粒子物理胶子场 QCD 强子化希格斯机制量子力学量子色动力学太电子伏深度非弹性散射质子衰变

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320m气象塔太阳辐射梯度观测

太阳能学报 2003年第3期24卷 295-301页

作者：刘广仁王跃思胡非张文胡玉琼中国科学院大气物理研究所cern/LAPC 北京100029

该文介绍了利用北京 32 0m气象塔进行太阳辐射梯度测量的仪器装置和初步观测结果。实验表明 ,自行设计制造的太阳辐射自动观测系统 (包括自动太阳跟踪器和数据采集系统 )运行可靠 ,可满足观测要求。初步实验观测结果表明 ,地面与 32 0m... 详细信息

该文介绍了利用北京 32 0m气象塔进行太阳辐射梯度测量的仪器装置和初步观测结果。实验表明 ,自行设计制造的太阳辐射自动观测系统 (包括自动太阳跟踪器和数据采集系统 )运行可靠 ,可满足观测要求。初步实验观测结果表明 ,地面与 32 0m高度之间的辐射衰减明显 ,在极晴好天气下太阳直接辐射在中午时段相差仅 10W/m2 左右 ,而在近地面污染严重的条件下其相对差值最大可达 14 0W/m2 左右。在晴好天气下总紫外辐射高空与地面相对差值很小 ;在大气能见度差时总紫外辐射值减少 ,但是高空与地面的差值相对加大。

关键词：辐射梯度观测太阳自动跟踪装置气象塔太阳辐射

Simulating CO_2 flux of three different ecosystems in ChinaFLUX based on artificial neural networks

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Science China Earth Sciences 2006年第S2期49卷 252-261页

作者： HE Honglin, YU Guirui, ZHANG Leiming, SUN Xiaomin & SU Wen Key Laboratory of Ecosystem Network Observation and Modeling, cern Synthesis Research Center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China

The nonlinearity of the relationship between CO2 flux and other micrometeorological variables flux parameters limits the applicability of carbon flux models to accurately estimate the flux dynamics. However, the need for carbon dioxide (CO2) estimations covering larger areas and the limitations of the point eddy covariance technique to address this requirement necessitates the modeling of CO2 flux from other micrometeorological variables. Artificial neural networks (ANN) are used because of their power to fit highly nonlinear relations between input and output variables without explaining the nature of the phenomena. This paper applied a multilayer perception ANN technique with error back propagation algorithm to simulate CO2 flux on three different ecosystems (forest, grassland and cropland) in ChinaFLUX. Energy flux (net radiation, latent heat, sensible heat and soil heat flux) and temperature (air and soil) and soil moisture were used to train the ANN and predict the CO2 flux. Diurnal half-hourly fluxes data of observations from June to August in 2003 were divided into training, validating and testing. Results of the CO2 flux simulation show that the technique can successfully predict the observed values with R2 value between 0.75 and 0.866. It is also found that the soil moisture could not improve the simulative accuracy without water stress. The analysis of the contribution of input variables in ANN shows that the ANN is not a black box model, it can tell us about the controlling parameters of NEE in different ecosystems and micrometeorological environment. The results indicate the ANN is not only a reliable, efficient technique to estimate regional or global CO2 flux from point measurements and understand the spatiotemporal budget of the CO2 fluxes, but also can identify the relations between the CO2 flux and micrometeorological variables.

关键词： artificial neural network CO2 ChinaFLUX energy flux variables contribution.