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Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

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Science china(Technological sciences) 2005年第z1期48卷 65-80页

作者： LIU Bingshan1, LI Shihai1, ZHANG Lei1,2.& WANG Jianguo31. Institute of Mechanics, chinese academy of {2., beijing 100080, china 2. graduate School, chinese academy of {2., beijing 100060, china 3. Tropical Marine Science Institute, National university of Singapore, 10 Kent Ridge Crescent, Singapore 1192.0 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

When the sliding mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form higher artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding forces of the sliding mass, thus lowering the safety factor, and inducing landslide disasters. In this paper, a landslide experimental apparatus is designed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying pressure is a crucial parameter affecting the stability of the slope; (2. when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3) the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying rock and soil on the upper 30% area. In this article, a discrete element method simulation is used to investigate the influence of cleft water pressure and shearing strength on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a high level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of china

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Science china(Technological sciences) 2006年第z1期49卷 177-188页

作者： WANG Shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & WANG Qingli Institute of Applied Ecology, chinese academy of {2., Shenyang 110016, china graduate university of chinese academy of {2., beijing 100039, china State Key Lab of Systems Ecology, Research Center for Eco-Environmental {2., chinese academy of {2., beijing 100085, china Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China graduate university of {2. academy of sciences Beijing 100039 China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast china. The probability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.

2.2. Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of chinese Geriatrics Society,beijing Hypertension Association,National Clinical Research Center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

Trend of urban system structure under the restriction of water and land resources in Xinjiang

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chinese Science Bulletin 2006年第A01期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun Xinjiang Institute of Ecology and Geography, chinese academy of {2., Urumqi 830011, china Institute of Geographical Science and Natural Resources Research, chinese academy of {2., beijing 100101, china graduate School, chinese academy of {2., beijing 100039, china chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 Xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

Photodissociation/photoionization processes of chlorobromomethane induced by femtosecond laser pulses with pump-probe scheme

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chinese Science Bulletin 2008年第5期53卷 681-686页

作者： ZHANG Feng1,2. WEI ZhengRong1,2. CAO ZhenZhou1,2. ZHANG ChangHua1,2.& ZHANG Bing1,2.1 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, chinese academy of {2., Wuhan 430071, china 2.graduate university of chinese academy of {2., beijing 100039, china State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China graduate university of {2. academy of sciences Beijing China

The photodissociation/photoionization processes of chlorobromomethane (CH_2.rCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2.rCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2.l^+ and CH_2.r^+) and the parent ion (CH_2.rCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2.l^+ and CH_2.r^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2., respectively.

关键词：毫微秒激光氯溴化甲烷激光探针光解作用光化电离作用

Effective solutions to a global 3D visual system in networking environments

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Science china Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3, YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, beijing Normal {2., beijing 100875, china 2. State Key Laboratory of Remote Sensing sciences, Institute of Remote Sensing Applications, chinese academy of sciences, beijing 101001, china 3. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 101001, china 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. chinese academy of {2. State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

Estimating forest aboveground biomass using HJ-1 Satellite CCD and ICESat GLAS waveform data

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Science china Earth sciences 2010年第S1期53卷 16-25页

作者： GUO ZhiFeng1,CHI Hong1,2.& SUN GuoQing1,3 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of chinese academy of {2. and beijing Normal university,Institute of Remote Sensing Applications,chinese academy of {2.,beijing 100101,china 2.10} university of chinese academy of {2.,beijing 1.0049,china 3Department of Geography university of Maryland,College Park,MD 2.742.USA 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Geography University of Maryland College Park MD 20742 USA

The ecosystem in northeastern china and the Russian Far East is a hotspot of scientific research into the global carbon *** aboveground biomass(AGB) is an important component in the land surface carbon *** this study,using forest inventory data and forest distribution data,the AGB was estimated for forest in Daxinganlin in northeastern china by combining charge-coupled device(CCD) data from the Small Satellite for Disaster and Environment Monitoring and Forecast(HJ-1) and Geoscience Laser Altimeter System(GLAS) waveform data from the Ice,Cloud and land Elevation Satellite(ICESat).The forest AGB prediction models were separately developed for different forest types in the research area at GLAS footprint level from GLAS waveform parameters and field survey plot biomass in the Changqing(CQ) Forest Center,which was calculated from forest inventory *** resulted statistical regression models have a R2.0.68 for conifer and R2.0.71 for broadleaf *** models were used to estimate biomass for all GLAS footprints of forest located in the study *** GLAS footprint biomass coupled with various spectral reflectivity parameters and vegetation indices derived from HJ-1 satellite CCD data were used in multiple regression analyses to establish biomass prediction models(R2.0.55 and R2.0.52.for needle and broadleaf respectively).Then the models were used to produce a forest AGB map for the whole study area using the HJ-1 *** data obtained from forest inventory data of the Zhuanglin(ZL) Forest Center were used as independent field measurements to validate the AGB estimated from HJ-1 CCD data(R2.0.71).About 80% of biomass samples had an error less than 2. t ha-1,and the mean error of all validation samples is 5.74 t *** pixel-level biomass map was then stratified into different biomass levels to illustrate the AGB spatial distribution pattern in this *** was found that HJ-1 wide-swath data and GLAS waveform data can be combined to estim

关键词： Disaster and Environment Monitoring and Forecast Satellite ICESat GLAS waveform boreal forest forest aboveground biomass multiple linear regression

Balanced multiple description subband coding based on multifilter banks

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Science china(Information sciences) 2011年第11期54卷 2359-2372页

作者： WANG Ning 1,LI BaoBin 2.& PENG LiZhong 1 1 LMAM,School of Mathematical sciences,Peking university,{2. 100871,china 2.School of Information Science and Engineering,graduate university of chinese academy of sciences,{2. 100190,china 1. LMAM School of Mathematical Sciences Peking University Beijing 100871 China2. School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing 100190 China

Multiple description coding is one of the source coding techniques to alleviate the problems of packet loss in *** encoder generates several different descriptions of the source and the decoder can produce a useful reconstruction with any received subset of these *** of the earlier works concentrated on redundancy and the average distortion of the single-description reconstructions,which is insufficient to describe the *** this paper,a metric of the coding system,balance eccentric modulus,is defined to evaluate the difference in quality between the individual *** the discrete wavelet transform becomes trivial polyphase transform when setting the balance eccentric modulus at zero,we introduce a multiwavelet based scheme ***,a sufficient condition for balanced multiwavelet based multiple description coding is presented.

关键词： multiple description coding rate-distortion theory balance eccentric modulus balanced multiwavelet multifilter bank

Possible Energy Network with polygeneration system and CCS for china

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中国科学：技术科学英文版 2010年第1期53卷 33-39页

作者： GAO Lin1,LI Sheng1,2.JIN HongGuang1 & LIN Hu1 1 Institute of Engineering Thermophysics,chinese academy of {2.,beijing 100190,china 2.graduate School of chinese academy of {2.,beijing 100039,china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2.with near zero energy penalties,and storing CO2.on sites,a new kind of Energy Network can integrate energy utilization,CO2.capture,transportation and storage ***-economic analysis of this solution focusing on Inner Mongolia and the Yangtze River Delta districts had been carried with comparison to the chain method for energy utilization and CO2.*** solution can save 2..5% of energy,and reduce 35% of total *** adoption of advanced polygeneration systems contributes 52.2. of the total saved costs,and the integration of energy utilization and CO2.sequestration in the Energy Network contributes 47.8%.From the aspect of CCS,the CO2.sequestration cost in the Energy Network can be as low as 12.$/t due to the lower energy penalties of capture in polygeneration systems and the combination of CO2.source and *** Energy Network exhibits attractive performance on energy saving,costs reduction for CCS,which may be a promising solution for sustainable development of china.

关键词： CO2 capture and storage Energy Network polygeneration system