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大兴安岭北坡落叶松林火后植被演替过程研究

生态学杂志 2004年第5期23卷 35-41页

作者：王绪高李秀珍贺红士冷文芳问青春中国科学院沈阳应用生态研究所

采用由植被空间序列推断时间系列的方法 ,分析大兴安岭呼中林区近 2.0年来不同火烧迹地植被变化情况。结果表明 ,森林火后初始 ,植物尤其是草本物种迅速增多 ,火烧迹地的植被主要由草本所占据 ,但随着时间的推移 ,草本物种不仅在数量上... 详细信息

采用由植被空间序列推断时间系列的方法 ,分析大兴安岭呼中林区近 2.0年来不同火烧迹地植被变化情况。结果表明 ,森林火后初始 ,植物尤其是草本物种迅速增多 ,火烧迹地的植被主要由草本所占据 ,但随着时间的推移 ,草本物种不仅在数量上有明显减少 ,在物种组成上有很大的变化 ,而且盖度也逐渐减少。灌木及乔木物种由于种类较少 ,在种类及组成上演替初期变化不如草本明显 ,但是盖度却逐渐增多。在本地区火后植被次生演替过程中 ,高频物种所占的比例较高且呈上升趋势 ,这明显有悖于Raunkiaer频度定律关于在相对稳定的群落中高频物种所占的比例应相对较低的规律。另外 ,不同火烧迹地间灌木的物种相似度明显高于草本的物种相似度 ,火烧年份相近的火烧迹地上的草本物种相似度要明显高于火烧年份远的草本物种相似度 ,但灌木间的物种相似度却没有出现这种现象 ,没有明显的规律。

关键词：大兴安岭火烧迹地演替

公共投资与区域就业变动——基于动态面板数据模型的经验分析

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上海财经大学学报（哲学社会科学版） 2010年第6期12卷 54-62页

作者：苑德宇中国社会科学院财政与贸易经济研究所北京100836

本文构建了反映劳动力市场均衡就业量与公共基础设施水平之间关系的动态模型,分别利用全国2.个省及东、中、西部各地区省份2.02.2.08年面板数据对公共投资的就业效应进行了实证分析。结果显示,就业存在较强的跨期路径依赖性;公路密度增... 详细信息

本文构建了反映劳动力市场均衡就业量与公共基础设施水平之间关系的动态模型,分别利用全国2.个省及东、中、西部各地区省份2.02.2.08年面板数据对公共投资的就业效应进行了实证分析。结果显示,就业存在较强的跨期路径依赖性;公路密度增加仅在短期内促进了就业水平的提高;人均普通中学拥有率增加在短期内对就业有挤出作用,但在长期中却存在更大反方向效应;同类公共投资对就业变动的影响显示出一定区域差异性。

关键词：公共投资就业变动动态面板数据模型

Gaining effciency via weighted estimators for multivariate failure time data

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Science china Mathematics 2009年第6期52卷 1113-1128页

作者： FAN JianQing1,2.ZHOU Yong2.3,CAI JianWen4 & CHEN Min3 1 Department of Operations Research and Financial Engineering,Princeton university,Princeton,NJ08544,USA 2.Department of Statistics,Shanghai university of Finance and Economics,Shanghai 2.0433,{2. 3 Institute of Applied Mathematics,academy of Mathematics and Systems Science,chinese academy of Sci-ences,beijing 100190,{2. 4 Department of Biostatistics,university of North Carolina at Chapel Hill,Chapel Hill,NC 2.599-742.,USA

Multivariate failure time data arise frequently in survival analysis.A commonly used tech-nique is the working independence estimator for marginal hazard *** natural questions are how to improve the effciency of the working independence estimator and how to identify the situations under which such an estimator has high statistical *** this paper,three weighted estimators are proposed based on three different optimal criteria in terms of the asymptotic covariance of weighted ***-form solutions are found,which always outperform the working indepen-dence *** also prove that the working independence estimator has high statistical effciency,when asymptotic covariance of derivatives of partial log-likelihood functions is nearly exchangeable or *** are conducted to compare the performance of the weighted estimator and work-ing independence estimator.A data set from Busselton population health surveys is analyzed using the proposed estimators.

关键词： marginal hazard model pseudo-partial likelihood working independence estimator optimal weight

INVESTIGATION ON SIGNAL REGULATION OF EUPATORIUM ADENOPHORUM ON ITS ALLELOPATHIC EFFECTS

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INVESTIGATION ON SIGNAL REGULATION OF EUPATORIUM ADENOPHORUM...

外周血循环浆细胞流式细胞术检测在浆细胞病中的应用中国专家共识(2.2.年版)

International Congress on Biological Invasions

作者： Jian YAN~1,Hai-Hong BI~1,Ya-Nan JIN~2.Fang-Hao WAN~2.and Jian-Wen TAN~1 1 CAS Key laboratory of Plant Resources Conservation and Sustainable Utilization,South china Botanic Garden,chinese {2. of Sciences,Guangzhou 510650,china. 2.State Key Laboratory for Biology of Plant Disease and Insect Pests,Institute of Plant Protection,chinese {2. of Agricultural Sciences,beijing 100094,china

Eupatorium adenophorum Spreng.,native to Mexico,is well-known as an invasive plant in many tropical and subtropical countries of the world as well as in *** exotic plant is extremely ecologically destructive to local biodiversity at its new locations and its rapid spreading has caused great economic losses in those seriously invaded *** far,though diverse studies have indicated that allelopathy would be one of the key factors for the invasive success of this noxious plant,the answers for the two questions abour what and how allelochemicals are involved in its allelopathic strategy are still largely ***,we started a new research to investigate the potential significance of defence-related signal regulation of E. adenophorum on its allelopathic *** this presentation,progress in our recent study on investigating the potential significance of defence-related signal regulation of *** on its allelopathic effects will be *** details of the progress will include the designation and preparation of defence-related signals and their functional mimics,the detection of endogenous signals in fresh tissues by GC-NCI-MS based analytic methods,the characterization of potential allelochemicals in root exudates,the analysis of signal-induced secondary metabolites and their secretion or exudation from living ***,some related interesting ongoing works including the identification of new chemical constituents from fresh living tissue extracts of *** will also be briefly presented and discussed.

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中华血液学杂志 2024年第4期45卷 313-321页

作者：中华医学会血液学分会浆细胞疾病学组中华医学会血液学分会实验诊断学组胡豫吴德沛黄晓军孙春艳蔡丽不详华中科技大学同济医学院附属协和医院武汉430022 苏州大学附属第一医院苏州215006 北京大学人民医院北京100044

流式细胞术检测外周血循环浆细胞(circulating plasma cells,CPCs)在浆细胞病的诊疗中已经展示出了重要价值。为促进流式细胞术检测CPCs在临床中的规范使用,特制定本共识。本共识依据循证原则,明确了意义未明的单克隆免疫球蛋白血症、... 详细信息

流式细胞术检测外周血循环浆细胞(circulating plasma cells,CPCs)在浆细胞病的诊疗中已经展示出了重要价值。为促进流式细胞术检测CPCs在临床中的规范使用,特制定本共识。本共识依据循证原则,明确了意义未明的单克隆免疫球蛋白血症、冒烟型骨髓瘤、多发性骨髓瘤和浆细胞白血病进行CPCs检测的时机与价值,并对CPCs的流式细胞术检测方法进行规范。

关键词：浆细胞病流式细胞术循环浆细胞

Research and development of chinese LCA database and LCA software

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Rare Metals 2006年第z2期25卷 101-104页

作者： GONG Xianzheng NIE Zuoren Wang Zhihong ZUO Tieyong College of Materials Science and Engineering Beijing University of Technology Beijing 100022 China College of Materials Science and Engineering Beijing University of Technology Beijing 100022 China College of Materials Science and Engineering Beijing University of Technology Beijing 100022 China College of Materials Science and Engineering Beijing University of Technology Beijing 100022 China

This paper detailed introduces the related work for building chinese National Database, Sinocenter, of materials life cycle assessment (MLCA) and developing the environmental burden dataset of materials. The MLCA database was built in 2.04, and the basic framework mainly includes LCA methodology, materials environmental dataset about energy consumption, resource input and environmental emissions. Nowadays, the database contains about fifty-thousand records of the main materials industries, such as cement, iron and steel, nonferrous metal, etc., and also includes the primary LCI data of fossil fuels and electricity grid in china. At the same time, the LCA method localization work is going on, for instance, calculated the resource characterization factors of 42.kinds of metal and 58 sorts of nonmetal, and also obtained some heavy metal impact factors in water. Based on the database, the iron and steel dataset has been developed with the data quality analysis, and some environmental burden data could be queried in our website, ***, in the future. Lastly, according to the framework of the ISO14040 series standards, the antitype of chinese LCA evaluation system was developed to support materials and products LCA evaluation in china.

关键词： database dataset environmental burden data quality LCI

Ceometric calibration of high-resolution remote sensing sensors

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Ceometric calibration of high-resolution remote sensing sens...

Percolated Monte Carlo Simulation Approach for Optimization of Soft Real-Time System Design

5th Asian Symposium on Geographic Information System from Computer Science & Engineering View

作者： LIANG Hong-you~(1,2.3) GU Xing-fa~1 TAO Yu~1 QIAO Chao-fei~4 (1.graduate university of {2. academy of Sciences,beijing 100039,P.R.china 2.State Key Laboratory of Remote Sensing Science,Institute of Remote Sensing Applications,CAS,beijing 100101,P.R.china 3.Henan Polytechnic university,Jiaozuo 454003,P.R.china 4.Development and Research Center for Surveying and Mapping State Bureau of Surveying and Mapping,beijing 100044,P.R.china)

＜正＞This paper introduces the applications of high-resolution remote sensing imagery and the necessity of geometric calibration for remote sensing sensors considering assurance of the geometric accuracy of remote sensing *** the paper analyzes the general methodology of geometric *** the DMC sensor geometric calibration as an exam- ple,the paper discusses the whole calibration ***,it gave some concluding remarks on geometric calibration of high-resolution remote sensing sensors.

关键词： digital camera geometric calibration geometric correction remote sensing

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Percolated Monte Carlo Simulation Approach for Optimization ...

ISOLATION AND STRUCTURE DETERMINATION OF LAMIOPHLOMICL C,A NEW HIGHLY OXYGENATED IRIDOID FROM LAMIOPHLOMIS ROTATA

第二十七届中国控制会议

作者： Zhou Peng 1,Lin jian2.1.School of Economic and Magement,beijing university of Aeronautics & Astronautics,beijing 100083,P.R.china 2.School of Economic and Magement,beijing university of Aeronautics & Astronautics,beijing 100083,P.R.china

A novel concept of probabilistic design for soft real-time systems and a simulation methodology to optimize the design are *** by the challenge of how to design but not over-design,the Probabilistic Design,is the process of accurately accounting for and mitigating the effects of variation in part geometry and other environmental conditions while at the same time optimizing a target performance *** classical mathematical methods,probabilistic design can be a very difficult and complex *** goal is to bridge the gap between real-time analysis and optimization for robust and reliable system *** method that is both simple and novel takes advantage of soft real-time system’s unique features to avoid over-designing the system.

关键词： Percolated Monte Carlo Simulations optimization

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chinese Chemical Letters 1990年第1期1卷 23-24页

作者： Jin Hai YI Chi Chang ZHONG Ze Yuan LUO Sichuan Institute of chinese Materia Medica,Chongqing,630065Zhuo Yin XIAO West china {2. of Medical Soience,Chengdu,610041Bin WU Qi Tai ZHENG Institute of Materia Medica,chinese academy of Medical Sciences,beijing,100050

A new highly oxygenated iridoid,lamiophlomiol C,was isolated from the roots of Lamiophlomis rotata and its structure was elucidated by spectrosoopic techniques and X-ray diffraction.

关键词： ISOLATION AND STRUCTURE DETERMINATION OF LAMIOPHLOMICL C A NEW HIGHLY OXYGENATED IRIDOID FROM LAMIOPHLOMIS ROTATA